/* -*- Mode: C; tab-width: 4 -*-
*
- * Copyright (c) 2002-2006 Apple Computer, Inc. All rights reserved.
+ * Copyright (c) 2002-2013 Apple Computer, Inc. All rights reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
- *
+ *
* http://www.apache.org/licenses/LICENSE-2.0
- *
+ *
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
*
* This code is completely 100% portable C. It does not depend on any external header files
* from outside the mDNS project -- all the types it expects to find are defined right here.
- *
+ *
* The previous point is very important: This file does not depend on any external
* header files. It should compile on *any* platform that has a C compiler, without
* making *any* assumptions about availability of so-called "standard" C functions,
* routines, or types (which may or may not be present on any given platform).
-
- * Formatting notes:
- * This code follows the "Whitesmiths style" C indentation rules. Plenty of discussion
- * on C indentation can be found on the web, such as <http://www.kafejo.com/komp/1tbs.htm>,
- * but for the sake of brevity here I will say just this: Curly braces are not syntactially
- * part of an "if" statement; they are the beginning and ending markers of a compound statement;
- * therefore common sense dictates that if they are part of a compound statement then they
- * should be indented to the same level as everything else in that compound statement.
- * Indenting curly braces at the same level as the "if" implies that curly braces are
- * part of the "if", which is false. (This is as misleading as people who write "char* x,y;"
- * thinking that variables x and y are both of type "char*" -- and anyone who doesn't
- * understand why variable y is not of type "char*" just proves the point that poor code
- * layout leads people to unfortunate misunderstandings about how the C language really works.)
*/
-#include "DNSCommon.h" // Defines general DNS untility routines
-#include "uDNS.h" // Defines entry points into unicast-specific routines
+#include "DNSCommon.h" // Defines general DNS utility routines
+#include "uDNS.h" // Defines entry points into unicast-specific routines
+#include "nsec.h"
+#include "dnssec.h"
+#include "anonymous.h"
// Disable certain benign warnings with Microsoft compilers
-#if(defined(_MSC_VER))
- // Disable "conditional expression is constant" warning for debug macros.
- // Otherwise, this generates warnings for the perfectly natural construct "while(1)"
- // If someone knows a variant way of writing "while(1)" that doesn't generate warning messages, please let us know
- #pragma warning(disable:4127)
-
- // Disable "assignment within conditional expression".
- // Other compilers understand the convention that if you place the assignment expression within an extra pair
- // of parentheses, this signals to the compiler that you really intended an assignment and no warning is necessary.
- // The Microsoft compiler doesn't understand this convention, so in the absense of any other way to signal
- // to the compiler that the assignment is intentional, we have to just turn this warning off completely.
- #pragma warning(disable:4706)
+#if (defined(_MSC_VER))
+// Disable "conditional expression is constant" warning for debug macros.
+// Otherwise, this generates warnings for the perfectly natural construct "while(1)"
+// If someone knows a variant way of writing "while(1)" that doesn't generate warning messages, please let us know
+ #pragma warning(disable:4127)
+
+// Disable "assignment within conditional expression".
+// Other compilers understand the convention that if you place the assignment expression within an extra pair
+// of parentheses, this signals to the compiler that you really intended an assignment and no warning is necessary.
+// The Microsoft compiler doesn't understand this convention, so in the absense of any other way to signal
+// to the compiler that the assignment is intentional, we have to just turn this warning off completely.
+ #pragma warning(disable:4706)
#endif
+#include "dns_sd.h" // for kDNSServiceFlags* definitions
+
#if APPLE_OSX_mDNSResponder
#include <WebFilterDNS/WebFilterDNS.h>
-#if ! NO_WCF
+#if !NO_WCF
WCFConnection *WCFConnectionNew(void) __attribute__((weak_import));
void WCFConnectionDealloc(WCFConnection* c) __attribute__((weak_import));
mDNSlocal void SendWakeup(mDNS *const m, mDNSInterfaceID InterfaceID, mDNSEthAddr *EthAddr, mDNSOpaque48 *password);
mDNSlocal mDNSBool CacheRecordRmvEventsForQuestion(mDNS *const m, DNSQuestion *q);
mDNSlocal mDNSBool LocalRecordRmvEventsForQuestion(mDNS *const m, DNSQuestion *q);
-mDNSlocal void mDNS_PurgeBeforeResolve(mDNS *const m, DNSQuestion *q);
+mDNSlocal void mDNS_PurgeForQuestion(mDNS *const m, DNSQuestion *q);
+mDNSlocal void CheckForDNSSECRecords(mDNS *const m, DNSQuestion *q);
+mDNSlocal void mDNS_SendKeepalives(mDNS *const m);
+mDNSlocal void mDNS_ExtractKeepaliveInfo(AuthRecord *ar, mDNSu32 *timeout, mDNSAddr *laddr, mDNSAddr *raddr, mDNSEthAddr *eth,
+ mDNSu32 *seq, mDNSu32 *ack, mDNSIPPort *lport, mDNSIPPort *rport, mDNSu16 *win);
+
+mDNSlocal void AdvertiseAllInterfaceRecords(mDNS *const m);
+mDNSlocal void DeadvertiseAllInterfaceRecords(mDNS *const m);
+mDNSlocal void FreeNSECRecords(mDNS *const m, CacheRecord *NSECRecords);
+mDNSlocal void mDNSParseNSEC3Records(mDNS *const m, const DNSMessage *const response, const mDNSu8 *end,
+ const mDNSInterfaceID InterfaceID, CacheRecord **NSEC3Records);
+
// ***************************************************************************
#if COMPILER_LIKES_PRAGMA_MARK
#pragma mark - Program Constants
#endif
-#define NO_HINFO 1
+// To Turn OFF mDNS_Tracer set MDNS_TRACER to 0 or undef it
+#define MDNS_TRACER 1
+#define NO_HINFO 1
// Any records bigger than this are considered 'large' records
#define SmallRecordLimit 1024
#define kMaxUpdateCredits 10
#define kUpdateCreditRefreshInterval (mDNSPlatformOneSecond * 6)
+// define special NR_AnswerTo values
+#define NR_AnswerMulticast (mDNSu8*)~0
+#define NR_AnswerUnicast (mDNSu8*)~1
+
+// Defined to set the kDNSQClass_UnicastResponse bit in the first four query packets.
+// else, it's just set it the first query.
+#define mDNS_REQUEST_UNICAST_RESPONSE 0
+
+// The code (see SendQueries() and BuildQuestion()) needs to have the
+// RequestUnicast value set to a value one greater than the number of times you want the query
+// sent with the "request unicast response" (QU) bit set.
+#define SET_QU_IN_FIRST_QUERY 2
+#define SET_QU_IN_FIRST_FOUR_QUERIES 5
+
+
mDNSexport const char *const mDNS_DomainTypeNames[] =
- {
- "b._dns-sd._udp.", // Browse
- "db._dns-sd._udp.", // Default Browse
- "lb._dns-sd._udp.", // Automatic Browse
- "r._dns-sd._udp.", // Registration
- "dr._dns-sd._udp." // Default Registration
- };
+{
+ "b._dns-sd._udp.", // Browse
+ "db._dns-sd._udp.", // Default Browse
+ "lb._dns-sd._udp.", // Automatic Browse
+ "r._dns-sd._udp.", // Registration
+ "dr._dns-sd._udp." // Default Registration
+};
#ifdef UNICAST_DISABLED
#define uDNS_IsActiveQuery(q, u) mDNSfalse
#pragma mark - General Utility Functions
#endif
-// If there is a authoritative LocalOnly record that answers questions of type A, AAAA and CNAME
-// this returns true. Main use is to handle /etc/hosts records.
-#define LORecordAnswersAddressType(rr) ((rr)->ARType == AuthRecordLocalOnly && \
- (rr)->resrec.RecordType & kDNSRecordTypeUniqueMask && \
- ((rr)->resrec.rrtype == kDNSType_A || (rr)->resrec.rrtype == kDNSType_AAAA || \
- (rr)->resrec.rrtype == kDNSType_CNAME))
-
-#define FollowCNAME(q, rr, AddRecord) (AddRecord && (q)->qtype != kDNSType_CNAME && \
- (rr)->RecordType != kDNSRecordTypePacketNegative && \
- (rr)->rrtype == kDNSType_CNAME)
+// Returns true if this is a unique, authoritative LocalOnly record that answers questions of type
+// A, AAAA , CNAME, or PTR. The caller should answer the question with this record and not send out
+// the question on the wire if LocalOnlyRecordAnswersQuestion() also returns true.
+// Main use is to handle /etc/hosts records and the LocalOnly PTR records created for localhost.
+#define UniqueLocalOnlyRecord(rr) ((rr)->ARType == AuthRecordLocalOnly && \
+ (rr)->resrec.RecordType & kDNSRecordTypeUniqueMask && \
+ ((rr)->resrec.rrtype == kDNSType_A || (rr)->resrec.rrtype == kDNSType_AAAA || \
+ (rr)->resrec.rrtype == kDNSType_CNAME || \
+ (rr)->resrec.rrtype == kDNSType_PTR))
mDNSlocal void SetNextQueryStopTime(mDNS *const m, const DNSQuestion *const q)
- {
- if (m->mDNS_busy != m->mDNS_reentrancy+1)
- LogMsg("SetNextQueryTime: Lock not held! mDNS_busy (%ld) mDNS_reentrancy (%ld)", m->mDNS_busy, m->mDNS_reentrancy);
+{
+ mDNS_CheckLock(m);
#if ForceAlerts
- if (m->mDNS_busy != m->mDNS_reentrancy+1) *(long*)0 = 0;
+ if (m->mDNS_busy != m->mDNS_reentrancy+1) *(long*)0 = 0;
#endif
- if (m->NextScheduledStopTime - q->StopTime > 0)
- m->NextScheduledStopTime = q->StopTime;
- }
+ if (m->NextScheduledStopTime - q->StopTime > 0)
+ m->NextScheduledStopTime = q->StopTime;
+}
mDNSexport void SetNextQueryTime(mDNS *const m, const DNSQuestion *const q)
- {
- if (m->mDNS_busy != m->mDNS_reentrancy+1)
- LogMsg("SetNextQueryTime: Lock not held! mDNS_busy (%ld) mDNS_reentrancy (%ld)", m->mDNS_busy, m->mDNS_reentrancy);
+{
+ mDNS_CheckLock(m);
#if ForceAlerts
- if (m->mDNS_busy != m->mDNS_reentrancy+1) *(long*)0 = 0;
+ if (m->mDNS_busy != m->mDNS_reentrancy+1) *(long*)0 = 0;
#endif
- if (ActiveQuestion(q))
- {
- // Depending on whether this is a multicast or unicast question we want to set either:
- // m->NextScheduledQuery = NextQSendTime(q) or
- // m->NextuDNSEvent = NextQSendTime(q)
- mDNSs32 *const timer = mDNSOpaque16IsZero(q->TargetQID) ? &m->NextScheduledQuery : &m->NextuDNSEvent;
- if (*timer - NextQSendTime(q) > 0)
- *timer = NextQSendTime(q);
- }
- }
+ if (ActiveQuestion(q))
+ {
+ // Depending on whether this is a multicast or unicast question we want to set either:
+ // m->NextScheduledQuery = NextQSendTime(q) or
+ // m->NextuDNSEvent = NextQSendTime(q)
+ mDNSs32 *const timer = mDNSOpaque16IsZero(q->TargetQID) ? &m->NextScheduledQuery : &m->NextuDNSEvent;
+ if (*timer - NextQSendTime(q) > 0)
+ *timer = NextQSendTime(q);
+ }
+}
mDNSlocal void ReleaseAuthEntity(AuthHash *r, AuthEntity *e)
- {
+{
#if APPLE_OSX_mDNSResponder && MACOSX_MDNS_MALLOC_DEBUGGING >= 1
- unsigned int i;
- for (i=0; i<sizeof(*e); i++) ((char*)e)[i] = 0xFF;
+ unsigned int i;
+ for (i=0; i<sizeof(*e); i++) ((char*)e)[i] = 0xFF;
#endif
- e->next = r->rrauth_free;
- r->rrauth_free = e;
- r->rrauth_totalused--;
- }
+ e->next = r->rrauth_free;
+ r->rrauth_free = e;
+ r->rrauth_totalused--;
+}
mDNSlocal void ReleaseAuthGroup(AuthHash *r, AuthGroup **cp)
- {
- AuthEntity *e = (AuthEntity *)(*cp);
- LogMsg("ReleaseAuthGroup: Releasing AuthGroup %##s", (*cp)->name->c);
- if ((*cp)->rrauth_tail != &(*cp)->members)
- LogMsg("ERROR: (*cp)->members == mDNSNULL but (*cp)->rrauth_tail != &(*cp)->members)");
- if ((*cp)->name != (domainname*)((*cp)->namestorage)) mDNSPlatformMemFree((*cp)->name);
- (*cp)->name = mDNSNULL;
- *cp = (*cp)->next; // Cut record from list
- ReleaseAuthEntity(r, e);
- }
+{
+ AuthEntity *e = (AuthEntity *)(*cp);
+ LogMsg("ReleaseAuthGroup: Releasing AuthGroup %##s", (*cp)->name->c);
+ if ((*cp)->rrauth_tail != &(*cp)->members)
+ LogMsg("ERROR: (*cp)->members == mDNSNULL but (*cp)->rrauth_tail != &(*cp)->members)");
+ if ((*cp)->name != (domainname*)((*cp)->namestorage)) mDNSPlatformMemFree((*cp)->name);
+ (*cp)->name = mDNSNULL;
+ *cp = (*cp)->next; // Cut record from list
+ ReleaseAuthEntity(r, e);
+}
mDNSlocal AuthEntity *GetAuthEntity(AuthHash *r, const AuthGroup *const PreserveAG)
- {
- AuthEntity *e = mDNSNULL;
+{
+ AuthEntity *e = mDNSNULL;
- if (r->rrauth_lock) { LogMsg("GetFreeCacheRR ERROR! Cache already locked!"); return(mDNSNULL); }
- r->rrauth_lock = 1;
-
- if (!r->rrauth_free)
- {
- // We allocate just one AuthEntity at a time because we need to be able
- // free them all individually which normally happens when we parse /etc/hosts into
- // AuthHash where we add the "new" entries and discard (free) the already added
- // entries. If we allocate as chunks, we can't free them individually.
- AuthEntity *storage = mDNSPlatformMemAllocate(sizeof(AuthEntity));
- storage->next = mDNSNULL;
- r->rrauth_free = storage;
- }
-
- // If we still have no free records, recycle all the records we can.
- // Enumerating the entire auth is moderately expensive, so when we do it, we reclaim all the records we can in one pass.
- if (!r->rrauth_free)
- {
- mDNSu32 oldtotalused = r->rrauth_totalused;
- mDNSu32 slot;
- for (slot = 0; slot < AUTH_HASH_SLOTS; slot++)
- {
- AuthGroup **cp = &r->rrauth_hash[slot];
- while (*cp)
- {
- if ((*cp)->members || (*cp)==PreserveAG) cp=&(*cp)->next;
- else ReleaseAuthGroup(r, cp);
- }
- }
- LogInfo("GetAuthEntity: Recycled %d records to reduce auth cache from %d to %d",
- oldtotalused - r->rrauth_totalused, oldtotalused, r->rrauth_totalused);
- }
-
- if (r->rrauth_free) // If there are records in the free list, take one
- {
- e = r->rrauth_free;
- r->rrauth_free = e->next;
- if (++r->rrauth_totalused >= r->rrauth_report)
- {
- LogInfo("RR Auth now using %ld objects", r->rrauth_totalused);
- if (r->rrauth_report < 100) r->rrauth_report += 10;
- else if (r->rrauth_report < 1000) r->rrauth_report += 100;
- else r->rrauth_report += 1000;
- }
- mDNSPlatformMemZero(e, sizeof(*e));
- }
-
- r->rrauth_lock = 0;
-
- return(e);
- }
+ if (r->rrauth_lock) { LogMsg("GetFreeCacheRR ERROR! Cache already locked!"); return(mDNSNULL); }
+ r->rrauth_lock = 1;
+
+ if (!r->rrauth_free)
+ {
+ // We allocate just one AuthEntity at a time because we need to be able
+ // free them all individually which normally happens when we parse /etc/hosts into
+ // AuthHash where we add the "new" entries and discard (free) the already added
+ // entries. If we allocate as chunks, we can't free them individually.
+ AuthEntity *storage = mDNSPlatformMemAllocate(sizeof(AuthEntity));
+ storage->next = mDNSNULL;
+ r->rrauth_free = storage;
+ }
+
+ // If we still have no free records, recycle all the records we can.
+ // Enumerating the entire auth is moderately expensive, so when we do it, we reclaim all the records we can in one pass.
+ if (!r->rrauth_free)
+ {
+ mDNSu32 oldtotalused = r->rrauth_totalused;
+ mDNSu32 slot;
+ for (slot = 0; slot < AUTH_HASH_SLOTS; slot++)
+ {
+ AuthGroup **cp = &r->rrauth_hash[slot];
+ while (*cp)
+ {
+ if ((*cp)->members || (*cp)==PreserveAG) cp=&(*cp)->next;
+ else ReleaseAuthGroup(r, cp);
+ }
+ }
+ LogInfo("GetAuthEntity: Recycled %d records to reduce auth cache from %d to %d",
+ oldtotalused - r->rrauth_totalused, oldtotalused, r->rrauth_totalused);
+ }
+
+ if (r->rrauth_free) // If there are records in the free list, take one
+ {
+ e = r->rrauth_free;
+ r->rrauth_free = e->next;
+ if (++r->rrauth_totalused >= r->rrauth_report)
+ {
+ LogInfo("RR Auth now using %ld objects", r->rrauth_totalused);
+ if (r->rrauth_report < 100) r->rrauth_report += 10;
+ else if (r->rrauth_report < 1000) r->rrauth_report += 100;
+ else r->rrauth_report += 1000;
+ }
+ mDNSPlatformMemZero(e, sizeof(*e));
+ }
+
+ r->rrauth_lock = 0;
+
+ return(e);
+}
mDNSexport AuthGroup *AuthGroupForName(AuthHash *r, const mDNSu32 slot, const mDNSu32 namehash, const domainname *const name)
- {
- AuthGroup *ag;
- for (ag = r->rrauth_hash[slot]; ag; ag=ag->next)
- if (ag->namehash == namehash && SameDomainName(ag->name, name))
- break;
- return(ag);
- }
+{
+ AuthGroup *ag;
+ for (ag = r->rrauth_hash[slot]; ag; ag=ag->next)
+ if (ag->namehash == namehash && SameDomainName(ag->name, name))
+ break;
+ return(ag);
+}
mDNSexport AuthGroup *AuthGroupForRecord(AuthHash *r, const mDNSu32 slot, const ResourceRecord *const rr)
- {
- return(AuthGroupForName(r, slot, rr->namehash, rr->name));
- }
+{
+ return(AuthGroupForName(r, slot, rr->namehash, rr->name));
+}
mDNSlocal AuthGroup *GetAuthGroup(AuthHash *r, const mDNSu32 slot, const ResourceRecord *const rr)
- {
- mDNSu16 namelen = DomainNameLength(rr->name);
- AuthGroup *ag = (AuthGroup*)GetAuthEntity(r, mDNSNULL);
- if (!ag) { LogMsg("GetAuthGroup: Failed to allocate memory for %##s", rr->name->c); return(mDNSNULL); }
- ag->next = r->rrauth_hash[slot];
- ag->namehash = rr->namehash;
- ag->members = mDNSNULL;
- ag->rrauth_tail = &ag->members;
- ag->name = (domainname*)ag->namestorage;
- ag->NewLocalOnlyRecords = mDNSNULL;
- if (namelen > InlineCacheGroupNameSize) ag->name = mDNSPlatformMemAllocate(namelen);
- if (!ag->name)
- {
- LogMsg("GetAuthGroup: Failed to allocate name storage for %##s", rr->name->c);
- ReleaseAuthEntity(r, (AuthEntity*)ag);
- return(mDNSNULL);
- }
- AssignDomainName(ag->name, rr->name);
-
- if (AuthGroupForRecord(r, slot, rr)) LogMsg("GetAuthGroup: Already have AuthGroup for %##s", rr->name->c);
- r->rrauth_hash[slot] = ag;
- if (AuthGroupForRecord(r, slot, rr) != ag) LogMsg("GetAuthGroup: Not finding AuthGroup for %##s", rr->name->c);
-
- return(ag);
- }
+{
+ mDNSu16 namelen = DomainNameLength(rr->name);
+ AuthGroup *ag = (AuthGroup*)GetAuthEntity(r, mDNSNULL);
+ if (!ag) { LogMsg("GetAuthGroup: Failed to allocate memory for %##s", rr->name->c); return(mDNSNULL); }
+ ag->next = r->rrauth_hash[slot];
+ ag->namehash = rr->namehash;
+ ag->members = mDNSNULL;
+ ag->rrauth_tail = &ag->members;
+ ag->NewLocalOnlyRecords = mDNSNULL;
+ if (namelen > sizeof(ag->namestorage))
+ ag->name = mDNSPlatformMemAllocate(namelen);
+ else
+ ag->name = (domainname*)ag->namestorage;
+ if (!ag->name)
+ {
+ LogMsg("GetAuthGroup: Failed to allocate name storage for %##s", rr->name->c);
+ ReleaseAuthEntity(r, (AuthEntity*)ag);
+ return(mDNSNULL);
+ }
+ AssignDomainName(ag->name, rr->name);
+
+ if (AuthGroupForRecord(r, slot, rr)) LogMsg("GetAuthGroup: Already have AuthGroup for %##s", rr->name->c);
+ r->rrauth_hash[slot] = ag;
+ if (AuthGroupForRecord(r, slot, rr) != ag) LogMsg("GetAuthGroup: Not finding AuthGroup for %##s", rr->name->c);
+
+ return(ag);
+}
// Returns the AuthGroup in which the AuthRecord was inserted
mDNSexport AuthGroup *InsertAuthRecord(mDNS *const m, AuthHash *r, AuthRecord *rr)
- {
- AuthGroup *ag;
- const mDNSu32 slot = AuthHashSlot(rr->resrec.name);
- ag = AuthGroupForRecord(r, slot, &rr->resrec);
- if (!ag) ag = GetAuthGroup(r, slot, &rr->resrec); // If we don't have a AuthGroup for this name, make one now
- if (ag)
- {
- LogInfo("InsertAuthRecord: inserting auth record %s from table", ARDisplayString(m, rr));
- *(ag->rrauth_tail) = rr; // Append this record to tail of cache slot list
- ag->rrauth_tail = &(rr->next); // Advance tail pointer
- }
- return ag;
- }
+{
+ AuthGroup *ag;
+ const mDNSu32 slot = AuthHashSlot(rr->resrec.name);
+ ag = AuthGroupForRecord(r, slot, &rr->resrec);
+ if (!ag) ag = GetAuthGroup(r, slot, &rr->resrec); // If we don't have a AuthGroup for this name, make one now
+ if (ag)
+ {
+ LogInfo("InsertAuthRecord: inserting auth record %s from table", ARDisplayString(m, rr));
+ *(ag->rrauth_tail) = rr; // Append this record to tail of cache slot list
+ ag->rrauth_tail = &(rr->next); // Advance tail pointer
+ }
+ return ag;
+}
mDNSexport AuthGroup *RemoveAuthRecord(mDNS *const m, AuthHash *r, AuthRecord *rr)
- {
- AuthGroup *a;
- AuthGroup **ag = &a;
- AuthRecord **rp;
- const mDNSu32 slot = AuthHashSlot(rr->resrec.name);
-
- a = AuthGroupForRecord(r, slot, &rr->resrec);
- if (!a) { LogMsg("RemoveAuthRecord: ERROR!! AuthGroup not found for %s", ARDisplayString(m, rr)); return mDNSNULL; }
- rp = &(*ag)->members;
- while (*rp)
- {
- if (*rp != rr)
- rp=&(*rp)->next;
- else
- {
- // We don't break here, so that we can set the tail below without tracking "prev" pointers
-
- LogInfo("RemoveAuthRecord: removing auth record %s from table", ARDisplayString(m, rr));
- *rp = (*rp)->next; // Cut record from list
- }
- }
- // TBD: If there are no more members, release authgroup ?
- (*ag)->rrauth_tail = rp;
- return a;
- }
+{
+ AuthGroup *a;
+ AuthGroup **ag = &a;
+ AuthRecord **rp;
+ const mDNSu32 slot = AuthHashSlot(rr->resrec.name);
+
+ a = AuthGroupForRecord(r, slot, &rr->resrec);
+ if (!a) { LogMsg("RemoveAuthRecord: ERROR!! AuthGroup not found for %s", ARDisplayString(m, rr)); return mDNSNULL; }
+ rp = &(*ag)->members;
+ while (*rp)
+ {
+ if (*rp != rr)
+ rp=&(*rp)->next;
+ else
+ {
+ // We don't break here, so that we can set the tail below without tracking "prev" pointers
+
+ LogInfo("RemoveAuthRecord: removing auth record %s from table", ARDisplayString(m, rr));
+ *rp = (*rp)->next; // Cut record from list
+ }
+ }
+ // TBD: If there are no more members, release authgroup ?
+ (*ag)->rrauth_tail = rp;
+ return a;
+}
mDNSexport CacheGroup *CacheGroupForName(const mDNS *const m, const mDNSu32 slot, const mDNSu32 namehash, const domainname *const name)
- {
- CacheGroup *cg;
- for (cg = m->rrcache_hash[slot]; cg; cg=cg->next)
- if (cg->namehash == namehash && SameDomainName(cg->name, name))
- break;
- return(cg);
- }
+{
+ CacheGroup *cg;
+ for (cg = m->rrcache_hash[slot]; cg; cg=cg->next)
+ if (cg->namehash == namehash && SameDomainName(cg->name, name))
+ break;
+ return(cg);
+}
mDNSlocal CacheGroup *CacheGroupForRecord(const mDNS *const m, const mDNSu32 slot, const ResourceRecord *const rr)
- {
- return(CacheGroupForName(m, slot, rr->namehash, rr->name));
- }
-
-mDNSexport mDNSBool mDNS_AddressIsLocalSubnet(mDNS *const m, const mDNSInterfaceID InterfaceID, const mDNSAddr *addr)
- {
- NetworkInterfaceInfo *intf;
-
- if (addr->type == mDNSAddrType_IPv4)
- {
- // Normally we resist touching the NotAnInteger fields, but here we're doing tricky bitwise masking so we make an exception
- if (mDNSv4AddressIsLinkLocal(&addr->ip.v4)) return(mDNStrue);
- for (intf = m->HostInterfaces; intf; intf = intf->next)
- if (intf->ip.type == addr->type && intf->InterfaceID == InterfaceID && intf->McastTxRx)
- if (((intf->ip.ip.v4.NotAnInteger ^ addr->ip.v4.NotAnInteger) & intf->mask.ip.v4.NotAnInteger) == 0)
- return(mDNStrue);
- }
-
- if (addr->type == mDNSAddrType_IPv6)
- {
- if (mDNSv6AddressIsLinkLocal(&addr->ip.v6)) return(mDNStrue);
- for (intf = m->HostInterfaces; intf; intf = intf->next)
- if (intf->ip.type == addr->type && intf->InterfaceID == InterfaceID && intf->McastTxRx)
- if ((((intf->ip.ip.v6.l[0] ^ addr->ip.v6.l[0]) & intf->mask.ip.v6.l[0]) == 0) &&
- (((intf->ip.ip.v6.l[1] ^ addr->ip.v6.l[1]) & intf->mask.ip.v6.l[1]) == 0) &&
- (((intf->ip.ip.v6.l[2] ^ addr->ip.v6.l[2]) & intf->mask.ip.v6.l[2]) == 0) &&
- (((intf->ip.ip.v6.l[3] ^ addr->ip.v6.l[3]) & intf->mask.ip.v6.l[3]) == 0))
- return(mDNStrue);
- }
-
- return(mDNSfalse);
- }
+{
+ return(CacheGroupForName(m, slot, rr->namehash, rr->name));
+}
+
+mDNSexport mDNSBool mDNS_AddressIsLocalSubnet(mDNS *const m, const mDNSInterfaceID InterfaceID, const mDNSAddr *addr, mDNSBool *myself)
+{
+ NetworkInterfaceInfo *intf;
+
+ if (addr->type == mDNSAddrType_IPv4)
+ {
+ // Normally we resist touching the NotAnInteger fields, but here we're doing tricky bitwise masking so we make an exception
+ if (mDNSv4AddressIsLinkLocal(&addr->ip.v4)) return(mDNStrue);
+ for (intf = m->HostInterfaces; intf; intf = intf->next)
+ if (intf->ip.type == addr->type && intf->InterfaceID == InterfaceID && intf->McastTxRx)
+ if (((intf->ip.ip.v4.NotAnInteger ^ addr->ip.v4.NotAnInteger) & intf->mask.ip.v4.NotAnInteger) == 0)
+ {
+ if (myself)
+ {
+ if (mDNSSameIPv4Address(intf->ip.ip.v4, addr->ip.v4))
+ *myself = mDNStrue;
+ else
+ *myself = mDNSfalse;
+ if (*myself)
+ debugf("mDNS_AddressIsLocalSubnet: IPv4 %#a returning true", addr);
+ else
+ debugf("mDNS_AddressIsLocalSubnet: IPv4 %#a returning false", addr);
+ }
+ return(mDNStrue);
+ }
+ }
+
+ if (addr->type == mDNSAddrType_IPv6)
+ {
+ for (intf = m->HostInterfaces; intf; intf = intf->next)
+ if (intf->ip.type == addr->type && intf->InterfaceID == InterfaceID && intf->McastTxRx)
+ if ((((intf->ip.ip.v6.l[0] ^ addr->ip.v6.l[0]) & intf->mask.ip.v6.l[0]) == 0) &&
+ (((intf->ip.ip.v6.l[1] ^ addr->ip.v6.l[1]) & intf->mask.ip.v6.l[1]) == 0) &&
+ (((intf->ip.ip.v6.l[2] ^ addr->ip.v6.l[2]) & intf->mask.ip.v6.l[2]) == 0) &&
+ (((intf->ip.ip.v6.l[3] ^ addr->ip.v6.l[3]) & intf->mask.ip.v6.l[3]) == 0))
+ {
+ if (myself)
+ {
+ if (mDNSSameIPv6Address(intf->ip.ip.v6, addr->ip.v6))
+ *myself = mDNStrue;
+ else
+ *myself = mDNSfalse;
+ if (*myself)
+ debugf("mDNS_AddressIsLocalSubnet: IPv6 %#a returning true", addr);
+ else
+ debugf("mDNS_AddressIsLocalSubnet: IPv6 %#a returning false", addr);
+ }
+ return(mDNStrue);
+ }
+ }
+
+ return(mDNSfalse);
+}
mDNSlocal NetworkInterfaceInfo *FirstInterfaceForID(mDNS *const m, const mDNSInterfaceID InterfaceID)
- {
- NetworkInterfaceInfo *intf = m->HostInterfaces;
- while (intf && intf->InterfaceID != InterfaceID) intf = intf->next;
- return(intf);
- }
+{
+ NetworkInterfaceInfo *intf = m->HostInterfaces;
+ while (intf && intf->InterfaceID != InterfaceID) intf = intf->next;
+ return(intf);
+}
+
+mDNSlocal NetworkInterfaceInfo *FirstIPv4LLInterfaceForID(mDNS *const m, const mDNSInterfaceID InterfaceID)
+{
+ NetworkInterfaceInfo *intf;
+
+ if (!InterfaceID)
+ return mDNSNULL;
+
+ // Note: We don't check for InterfaceActive, as the active interface could be IPv6 and
+ // we still want to find the first IPv4 Link-Local interface
+ for (intf = m->HostInterfaces; intf; intf = intf->next)
+ {
+ if (intf->InterfaceID == InterfaceID &&
+ intf->ip.type == mDNSAddrType_IPv4 && mDNSv4AddressIsLinkLocal(&intf->ip.ip.v4))
+ {
+ debugf("FirstIPv4LLInterfaceForID: found LL interface with address %.4a", &intf->ip.ip.v4);
+ return intf;
+ }
+ }
+ return (mDNSNULL);
+}
mDNSexport char *InterfaceNameForID(mDNS *const m, const mDNSInterfaceID InterfaceID)
- {
- NetworkInterfaceInfo *intf = FirstInterfaceForID(m, InterfaceID);
- return(intf ? intf->ifname : mDNSNULL);
- }
+{
+ NetworkInterfaceInfo *intf = FirstInterfaceForID(m, InterfaceID);
+ return(intf ? intf->ifname : mDNSNULL);
+}
// Caller should hold the lock
-mDNSlocal void GenerateNegativeResponse(mDNS *const m)
- {
- DNSQuestion *q;
- if (!m->CurrentQuestion) { LogMsg("GenerateNegativeResponse: ERROR!! CurrentQuestion not set"); return; }
- q = m->CurrentQuestion;
- LogInfo("GenerateNegativeResponse: Generating negative response for question %##s (%s)", q->qname.c, DNSTypeName(q->qtype));
-
- MakeNegativeCacheRecord(m, &m->rec.r, &q->qname, q->qnamehash, q->qtype, q->qclass, 60, mDNSInterface_Any, mDNSNULL);
- AnswerCurrentQuestionWithResourceRecord(m, &m->rec.r, QC_addnocache);
- if (m->CurrentQuestion == q) { q->ThisQInterval = 0; } // Deactivate this question
- // Don't touch the question after this
- m->rec.r.resrec.RecordType = 0; // Clear RecordType to show we're not still using it
- }
-
-mDNSlocal void AnswerQuestionByFollowingCNAME(mDNS *const m, DNSQuestion *q, ResourceRecord *rr)
- {
- const mDNSBool selfref = SameDomainName(&q->qname, &rr->rdata->u.name);
- if (q->CNAMEReferrals >= 10 || selfref)
- LogMsg("AnswerQuestionByFollowingCNAME: %p %##s (%s) NOT following CNAME referral %d%s for %s",
- q, q->qname.c, DNSTypeName(q->qtype), q->CNAMEReferrals, selfref ? " (Self-Referential)" : "", RRDisplayString(m, rr));
- else
- {
- const mDNSu32 c = q->CNAMEReferrals + 1; // Stash a copy of the new q->CNAMEReferrals value
-
- // The SameDomainName check above is to ignore bogus CNAME records that point right back at
- // themselves. Without that check we can get into a case where we have two duplicate questions,
- // A and B, and when we stop question A, UpdateQuestionDuplicates copies the value of CNAMEReferrals
- // from A to B, and then A is re-appended to the end of the list as a duplicate of B (because
- // the target name is still the same), and then when we stop question B, UpdateQuestionDuplicates
- // copies the B's value of CNAMEReferrals back to A, and we end up not incrementing CNAMEReferrals
- // for either of them. This is not a problem for CNAME loops of two or more records because in
- // those cases the newly re-appended question A has a different target name and therefore cannot be
- // a duplicate of any other question ('B') which was itself a duplicate of the previous question A.
-
- // Right now we just stop and re-use the existing query. If we really wanted to be 100% perfect,
- // and track CNAMEs coming and going, we should really create a subordinate query here,
- // which we would subsequently cancel and retract if the CNAME referral record were removed.
- // In reality this is such a corner case we'll ignore it until someone actually needs it.
-
- LogInfo("AnswerQuestionByFollowingCNAME: %p %##s (%s) following CNAME referral %d for %s",
- q, q->qname.c, DNSTypeName(q->qtype), q->CNAMEReferrals, RRDisplayString(m, rr));
-
- mDNS_StopQuery_internal(m, q); // Stop old query
- AssignDomainName(&q->qname, &rr->rdata->u.name); // Update qname
- q->qnamehash = DomainNameHashValue(&q->qname); // and namehash
- // If a unicast query results in a CNAME that points to a .local, we need to re-try
- // this as unicast. Setting the mDNSInterface_Unicast tells mDNS_StartQuery_internal
- // to try this as unicast query even though it is a .local name
- if (!mDNSOpaque16IsZero(q->TargetQID) && IsLocalDomain(&q->qname))
- {
- LogInfo("AnswerQuestionByFollowingCNAME: Resolving a .local CNAME %p %##s (%s) Record %s",
- q, q->qname.c, DNSTypeName(q->qtype), RRDisplayString(m, rr));
- q->InterfaceID = mDNSInterface_Unicast;
- }
- mDNS_StartQuery_internal(m, q); // start new query
- // Record how many times we've done this. We need to do this *after* mDNS_StartQuery_internal,
- // because mDNS_StartQuery_internal re-initializes CNAMEReferrals to zero
- q->CNAMEReferrals = c;
- }
- }
+mDNSlocal void GenerateNegativeResponse(mDNS *const m, QC_result qc)
+{
+ DNSQuestion *q;
+ if (!m->CurrentQuestion) { LogMsg("GenerateNegativeResponse: ERROR!! CurrentQuestion not set"); return; }
+ q = m->CurrentQuestion;
+ LogInfo("GenerateNegativeResponse: Generating negative response for question %##s (%s)", q->qname.c, DNSTypeName(q->qtype));
+
+ MakeNegativeCacheRecord(m, &m->rec.r, &q->qname, q->qnamehash, q->qtype, q->qclass, 60, mDNSInterface_Any, mDNSNULL);
+ // We need to force the response through in the following cases
+ //
+ // a) SuppressUnusable questions that are suppressed
+ // b) Append search domains and retry the question
+ //
+ // The question may not have set Intermediates in which case we don't deliver negative responses. So, to force
+ // through we use "QC_forceresponse".
+ AnswerCurrentQuestionWithResourceRecord(m, &m->rec.r, qc);
+ if (m->CurrentQuestion == q) { q->ThisQInterval = 0; } // Deactivate this question
+ // Don't touch the question after this
+ m->rec.r.resrec.RecordType = 0; // Clear RecordType to show we're not still using it
+}
+
+mDNSexport void AnswerQuestionByFollowingCNAME(mDNS *const m, DNSQuestion *q, ResourceRecord *rr)
+{
+ const mDNSBool selfref = SameDomainName(&q->qname, &rr->rdata->u.name);
+ if (q->CNAMEReferrals >= 10 || selfref)
+ {
+ LogMsg("AnswerQuestionByFollowingCNAME: %p %##s (%s) NOT following CNAME referral %d%s for %s",
+ q, q->qname.c, DNSTypeName(q->qtype), q->CNAMEReferrals, selfref ? " (Self-Referential)" : "", RRDisplayString(m, rr));
+ }
+ else
+ {
+ const mDNSu32 c = q->CNAMEReferrals + 1; // Stash a copy of the new q->CNAMEReferrals value
+ UDPSocket *sock = q->LocalSocket;
+ mDNSOpaque16 id = q->TargetQID;
+
+ // if there is a message waiting at the socket, we want to process that instead
+ // of throwing it away. If we have a CNAME response that answers
+ // both A and AAAA question and while answering it we don't want to throw
+ // away the response where the actual addresses are present.
+ if (mDNSPlatformPeekUDP(m, q->LocalSocket))
+ {
+ LogInfo("AnswerQuestionByFollowingCNAME: Preserving UDP socket for %##s (%s)", q->qname.c, DNSTypeName(q->qtype));
+ q->LocalSocket = mDNSNULL;
+ }
+ else
+ {
+ sock = mDNSNULL;
+ }
+
+ // The SameDomainName check above is to ignore bogus CNAME records that point right back at
+ // themselves. Without that check we can get into a case where we have two duplicate questions,
+ // A and B, and when we stop question A, UpdateQuestionDuplicates copies the value of CNAMEReferrals
+ // from A to B, and then A is re-appended to the end of the list as a duplicate of B (because
+ // the target name is still the same), and then when we stop question B, UpdateQuestionDuplicates
+ // copies the B's value of CNAMEReferrals back to A, and we end up not incrementing CNAMEReferrals
+ // for either of them. This is not a problem for CNAME loops of two or more records because in
+ // those cases the newly re-appended question A has a different target name and therefore cannot be
+ // a duplicate of any other question ('B') which was itself a duplicate of the previous question A.
+
+ // Right now we just stop and re-use the existing query. If we really wanted to be 100% perfect,
+ // and track CNAMEs coming and going, we should really create a subordinate query here,
+ // which we would subsequently cancel and retract if the CNAME referral record were removed.
+ // In reality this is such a corner case we'll ignore it until someone actually needs it.
+
+ LogInfo("AnswerQuestionByFollowingCNAME: %p %##s (%s) following CNAME referral %d for %s",
+ q, q->qname.c, DNSTypeName(q->qtype), q->CNAMEReferrals, RRDisplayString(m, rr));
+
+ mDNS_StopQuery_internal(m, q); // Stop old query
+ AssignDomainName(&q->qname, &rr->rdata->u.name); // Update qname
+ q->qnamehash = DomainNameHashValue(&q->qname); // and namehash
+ // If a unicast query results in a CNAME that points to a .local, we need to re-try
+ // this as unicast. Setting the mDNSInterface_Unicast tells mDNS_StartQuery_internal
+ // to try this as unicast query even though it is a .local name
+ if (!mDNSOpaque16IsZero(q->TargetQID) && IsLocalDomain(&q->qname))
+ {
+ LogInfo("AnswerQuestionByFollowingCNAME: Resolving a .local CNAME %p %##s (%s) Record %s",
+ q, q->qname.c, DNSTypeName(q->qtype), RRDisplayString(m, rr));
+ q->InterfaceID = mDNSInterface_Unicast;
+ }
+ mDNS_StartQuery_internal(m, q); // start new query
+ // Record how many times we've done this. We need to do this *after* mDNS_StartQuery_internal,
+ // because mDNS_StartQuery_internal re-initializes CNAMEReferrals to zero
+ q->CNAMEReferrals = c;
+ if (sock)
+ {
+ // We have a message waiting and that should answer this question.
+ if (q->LocalSocket)
+ mDNSPlatformUDPClose(q->LocalSocket);
+ q->LocalSocket = sock;
+ q->TargetQID = id;
+ }
+ }
+}
// For a single given DNSQuestion pointed to by CurrentQuestion, deliver an add/remove result for the single given AuthRecord
// Note: All the callers should use the m->CurrentQuestion to see if the question is still valid or not
mDNSlocal void AnswerLocalQuestionWithLocalAuthRecord(mDNS *const m, AuthRecord *rr, QC_result AddRecord)
- {
- DNSQuestion *q = m->CurrentQuestion;
- mDNSBool followcname;
-
- if (!q)
- {
- LogMsg("AnswerLocalQuestionWithLocalAuthRecord: ERROR!! CurrentQuestion NULL while answering with %s", ARDisplayString(m, rr));
- return;
- }
-
- followcname = FollowCNAME(q, &rr->resrec, AddRecord);
-
- // We should not be delivering results for record types Unregistered, Deregistering, and (unverified) Unique
- if (!(rr->resrec.RecordType & kDNSRecordTypeActiveMask))
- {
- LogMsg("AnswerLocalQuestionWithLocalAuthRecord: *NOT* delivering %s event for local record type %X %s",
- AddRecord ? "Add" : "Rmv", rr->resrec.RecordType, ARDisplayString(m, rr));
- return;
- }
-
- // Indicate that we've given at least one positive answer for this record, so we should be prepared to send a goodbye for it
- if (AddRecord) rr->AnsweredLocalQ = mDNStrue;
- mDNS_DropLockBeforeCallback(); // Allow client to legally make mDNS API calls from the callback
- if (q->QuestionCallback && !q->NoAnswer)
- {
- q->CurrentAnswers += AddRecord ? 1 : -1;
- if (LORecordAnswersAddressType(rr))
- {
- if (!followcname || q->ReturnIntermed)
- {
- // Don't send this packet on the wire as we answered from /etc/hosts
- q->ThisQInterval = 0;
- q->LOAddressAnswers += AddRecord ? 1 : -1;
- q->QuestionCallback(m, q, &rr->resrec, AddRecord);
- }
- mDNS_ReclaimLockAfterCallback(); // Decrement mDNS_reentrancy to block mDNS API calls again
- // The callback above could have caused the question to stop. Detect that
- // using m->CurrentQuestion
- if (followcname && m->CurrentQuestion == q)
- AnswerQuestionByFollowingCNAME(m, q, &rr->resrec);
- return;
- }
- else
- q->QuestionCallback(m, q, &rr->resrec, AddRecord);
- }
- mDNS_ReclaimLockAfterCallback(); // Decrement mDNS_reentrancy to block mDNS API calls again
- }
+{
+ DNSQuestion *q = m->CurrentQuestion;
+ mDNSBool followcname;
+
+ if (!q)
+ {
+ LogMsg("AnswerLocalQuestionWithLocalAuthRecord: ERROR!! CurrentQuestion NULL while answering with %s", ARDisplayString(m, rr));
+ return;
+ }
+
+ followcname = FollowCNAME(q, &rr->resrec, AddRecord);
+
+ // We should not be delivering results for record types Unregistered, Deregistering, and (unverified) Unique
+ if (!(rr->resrec.RecordType & kDNSRecordTypeActiveMask))
+ {
+ LogMsg("AnswerLocalQuestionWithLocalAuthRecord: *NOT* delivering %s event for local record type %X %s",
+ AddRecord ? "Add" : "Rmv", rr->resrec.RecordType, ARDisplayString(m, rr));
+ return;
+ }
+
+ // Indicate that we've given at least one positive answer for this record, so we should be prepared to send a goodbye for it
+ if (AddRecord) rr->AnsweredLocalQ = mDNStrue;
+ mDNS_DropLockBeforeCallback(); // Allow client to legally make mDNS API calls from the callback
+ if (q->QuestionCallback && !q->NoAnswer)
+ {
+ q->CurrentAnswers += AddRecord ? 1 : -1;
+ if (UniqueLocalOnlyRecord(rr))
+ {
+ if (!followcname || q->ReturnIntermed)
+ {
+ // Don't send this packet on the wire as we answered from /etc/hosts
+ q->ThisQInterval = 0;
+ q->LOAddressAnswers += AddRecord ? 1 : -1;
+ q->QuestionCallback(m, q, &rr->resrec, AddRecord);
+ }
+ mDNS_ReclaimLockAfterCallback(); // Decrement mDNS_reentrancy to block mDNS API calls again
+ // The callback above could have caused the question to stop. Detect that
+ // using m->CurrentQuestion
+ if (followcname && m->CurrentQuestion == q)
+ AnswerQuestionByFollowingCNAME(m, q, &rr->resrec);
+ return;
+ }
+ else
+ {
+ q->QuestionCallback(m, q, &rr->resrec, AddRecord);
+ }
+ }
+ mDNS_ReclaimLockAfterCallback(); // Decrement mDNS_reentrancy to block mDNS API calls again
+}
mDNSlocal void AnswerInterfaceAnyQuestionsWithLocalAuthRecord(mDNS *const m, AuthRecord *rr, QC_result AddRecord)
- {
- if (m->CurrentQuestion)
- LogMsg("AnswerInterfaceAnyQuestionsWithLocalAuthRecord: ERROR m->CurrentQuestion already set: %##s (%s)",
- m->CurrentQuestion->qname.c, DNSTypeName(m->CurrentQuestion->qtype));
- m->CurrentQuestion = m->Questions;
- while (m->CurrentQuestion && m->CurrentQuestion != m->NewQuestions)
- {
- mDNSBool answered;
- DNSQuestion *q = m->CurrentQuestion;
- if (RRAny(rr))
- answered = ResourceRecordAnswersQuestion(&rr->resrec, q);
- else
- answered = LocalOnlyRecordAnswersQuestion(rr, q);
- if (answered)
- AnswerLocalQuestionWithLocalAuthRecord(m, rr, AddRecord); // MUST NOT dereference q again
- if (m->CurrentQuestion == q) // If m->CurrentQuestion was not auto-advanced, do it ourselves now
- m->CurrentQuestion = q->next;
- }
- m->CurrentQuestion = mDNSNULL;
- }
+{
+ if (m->CurrentQuestion)
+ LogMsg("AnswerInterfaceAnyQuestionsWithLocalAuthRecord: ERROR m->CurrentQuestion already set: %##s (%s)",
+ m->CurrentQuestion->qname.c, DNSTypeName(m->CurrentQuestion->qtype));
+ m->CurrentQuestion = m->Questions;
+ while (m->CurrentQuestion && m->CurrentQuestion != m->NewQuestions)
+ {
+ mDNSBool answered;
+ DNSQuestion *q = m->CurrentQuestion;
+ if (RRAny(rr))
+ answered = ResourceRecordAnswersQuestion(&rr->resrec, q);
+ else
+ answered = LocalOnlyRecordAnswersQuestion(rr, q);
+ if (answered)
+ AnswerLocalQuestionWithLocalAuthRecord(m, rr, AddRecord); // MUST NOT dereference q again
+ if (m->CurrentQuestion == q) // If m->CurrentQuestion was not auto-advanced, do it ourselves now
+ m->CurrentQuestion = q->next;
+ }
+ m->CurrentQuestion = mDNSNULL;
+}
// When a new local AuthRecord is created or deleted, AnswerAllLocalQuestionsWithLocalAuthRecord()
// delivers the appropriate add/remove events to listening questions:
// and by mDNS_Deregister_internal()
mDNSlocal void AnswerAllLocalQuestionsWithLocalAuthRecord(mDNS *const m, AuthRecord *rr, QC_result AddRecord)
- {
- if (m->CurrentQuestion)
- LogMsg("AnswerAllLocalQuestionsWithLocalAuthRecord ERROR m->CurrentQuestion already set: %##s (%s)",
- m->CurrentQuestion->qname.c, DNSTypeName(m->CurrentQuestion->qtype));
-
- m->CurrentQuestion = m->LocalOnlyQuestions;
- while (m->CurrentQuestion && m->CurrentQuestion != m->NewLocalOnlyQuestions)
- {
- mDNSBool answered;
- DNSQuestion *q = m->CurrentQuestion;
- // We are called with both LocalOnly/P2P record or a regular AuthRecord
- if (RRAny(rr))
- answered = ResourceRecordAnswersQuestion(&rr->resrec, q);
- else
- answered = LocalOnlyRecordAnswersQuestion(rr, q);
- if (answered)
- AnswerLocalQuestionWithLocalAuthRecord(m, rr, AddRecord); // MUST NOT dereference q again
- if (m->CurrentQuestion == q) // If m->CurrentQuestion was not auto-advanced, do it ourselves now
- m->CurrentQuestion = q->next;
- }
-
- m->CurrentQuestion = mDNSNULL;
-
- // If this AuthRecord is marked LocalOnly or P2P, then we want to deliver it to all local 'mDNSInterface_Any' questions
- if (rr->ARType == AuthRecordLocalOnly || rr->ARType == AuthRecordP2P)
- AnswerInterfaceAnyQuestionsWithLocalAuthRecord(m, rr, AddRecord);
-
- }
+{
+ if (m->CurrentQuestion)
+ LogMsg("AnswerAllLocalQuestionsWithLocalAuthRecord ERROR m->CurrentQuestion already set: %##s (%s)",
+ m->CurrentQuestion->qname.c, DNSTypeName(m->CurrentQuestion->qtype));
+
+ m->CurrentQuestion = m->LocalOnlyQuestions;
+ while (m->CurrentQuestion && m->CurrentQuestion != m->NewLocalOnlyQuestions)
+ {
+ mDNSBool answered;
+ DNSQuestion *q = m->CurrentQuestion;
+ // We are called with both LocalOnly/P2P record or a regular AuthRecord
+ if (RRAny(rr))
+ answered = ResourceRecordAnswersQuestion(&rr->resrec, q);
+ else
+ answered = LocalOnlyRecordAnswersQuestion(rr, q);
+ if (answered)
+ AnswerLocalQuestionWithLocalAuthRecord(m, rr, AddRecord); // MUST NOT dereference q again
+ if (m->CurrentQuestion == q) // If m->CurrentQuestion was not auto-advanced, do it ourselves now
+ m->CurrentQuestion = q->next;
+ }
+
+ m->CurrentQuestion = mDNSNULL;
+
+ // If this AuthRecord is marked LocalOnly or P2P, then we want to deliver it to all local 'mDNSInterface_Any' questions
+ if (rr->ARType == AuthRecordLocalOnly || rr->ARType == AuthRecordP2P)
+ AnswerInterfaceAnyQuestionsWithLocalAuthRecord(m, rr, AddRecord);
+
+}
// ***************************************************************************
#if COMPILER_LIKES_PRAGMA_MARK
#define RRTypeIsAddressType(T) ((T) == kDNSType_A || (T) == kDNSType_AAAA)
-#define ResourceRecordIsValidAnswer(RR) ( ((RR)-> resrec.RecordType & kDNSRecordTypeActiveMask) && \
- ((RR)->Additional1 == mDNSNULL || ((RR)->Additional1->resrec.RecordType & kDNSRecordTypeActiveMask)) && \
- ((RR)->Additional2 == mDNSNULL || ((RR)->Additional2->resrec.RecordType & kDNSRecordTypeActiveMask)) && \
- ((RR)->DependentOn == mDNSNULL || ((RR)->DependentOn->resrec.RecordType & kDNSRecordTypeActiveMask)) )
+#define ResourceRecordIsValidAnswer(RR) ( ((RR)->resrec.RecordType & kDNSRecordTypeActiveMask) && \
+ ((RR)->Additional1 == mDNSNULL || ((RR)->Additional1->resrec.RecordType & kDNSRecordTypeActiveMask)) && \
+ ((RR)->Additional2 == mDNSNULL || ((RR)->Additional2->resrec.RecordType & kDNSRecordTypeActiveMask)) && \
+ ((RR)->DependentOn == mDNSNULL || ((RR)->DependentOn->resrec.RecordType & kDNSRecordTypeActiveMask)) )
#define ResourceRecordIsValidInterfaceAnswer(RR, INTID) \
- (ResourceRecordIsValidAnswer(RR) && \
- ((RR)->resrec.InterfaceID == mDNSInterface_Any || (RR)->resrec.InterfaceID == (INTID)))
+ (ResourceRecordIsValidAnswer(RR) && \
+ ((RR)->resrec.InterfaceID == mDNSInterface_Any || (RR)->resrec.InterfaceID == (INTID)))
#define DefaultProbeCountForTypeUnique ((mDNSu8)3)
#define DefaultProbeCountForRecordType(X) ((X) == kDNSRecordTypeUnique ? DefaultProbeCountForTypeUnique : (mDNSu8)0)
-#define InitialAnnounceCount ((mDNSu8)8)
+// See RFC 6762: "8.3 Announcing"
+// "The Multicast DNS responder MUST send at least two unsolicited responses, one second apart."
+// Send 4, which is really 8 since we send on both IPv4 and IPv6.
+#define InitialAnnounceCount ((mDNSu8)4)
// For goodbye packets we set the count to 3, and for wakeups we set it to 18
// (which will be up to 15 wakeup attempts over the course of 30 seconds,
// and then if the machine fails to wake, 3 goodbye packets).
#define GoodbyeCount ((mDNSu8)3)
#define WakeupCount ((mDNSu8)18)
+#define MAX_PROBE_RESTARTS ((mDNSu8)20)
// Number of wakeups we send if WakeOnResolve is set in the question
#define InitialWakeOnResolveCount ((mDNSu8)3)
#define DefaultAnnounceIntervalForTypeShared (mDNSPlatformOneSecond/2)
#define DefaultAnnounceIntervalForTypeUnique (mDNSPlatformOneSecond/2)
-#define DefaultAPIntervalForRecordType(X) ((X) & kDNSRecordTypeActiveSharedMask ? DefaultAnnounceIntervalForTypeShared : \
- (X) & kDNSRecordTypeUnique ? DefaultProbeIntervalForTypeUnique : \
- (X) & kDNSRecordTypeActiveUniqueMask ? DefaultAnnounceIntervalForTypeUnique : 0)
+#define DefaultAPIntervalForRecordType(X) ((X) &kDNSRecordTypeActiveSharedMask ? DefaultAnnounceIntervalForTypeShared : \
+ (X) &kDNSRecordTypeUnique ? DefaultProbeIntervalForTypeUnique : \
+ (X) &kDNSRecordTypeActiveUniqueMask ? DefaultAnnounceIntervalForTypeUnique : 0)
#define TimeToAnnounceThisRecord(RR,time) ((RR)->AnnounceCount && (time) - ((RR)->LastAPTime + (RR)->ThisAPInterval) >= 0)
#define TimeToSendThisRecord(RR,time) ((TimeToAnnounceThisRecord(RR,time) || (RR)->ImmedAnswer) && ResourceRecordIsValidAnswer(RR))
#define TicksTTL(RR) ((mDNSs32)(RR)->resrec.rroriginalttl * mDNSPlatformOneSecond)
#define RRExpireTime(RR) ((RR)->TimeRcvd + TicksTTL(RR))
+// Adjustment factor to avoid race condition (used for unicast cache entries) :
+// Suppose real record has TTL of 3600, and our local caching server has held it for 3500 seconds, so it returns an aged TTL of 100.
+// If we do our normal refresh at 80% of the TTL, our local caching server will return 20 seconds, so we'll do another
+// 80% refresh after 16 seconds, and then the server will return 4 seconds, and so on, in the fashion of Zeno's paradox.
+// To avoid this, we extend the record's effective TTL to give it a little extra grace period.
+// We adjust the 100 second TTL to 127. This means that when we do our 80% query at 102 seconds,
+// the cached copy at our local caching server will already have expired, so the server will be forced
+// to fetch a fresh copy from the authoritative server, and then return a fresh record with the full TTL of 3600 seconds.
+
+#define RRAdjustTTL(ttl) ((ttl) + ((ttl)/4) + 2)
+#define RRUnadjustedTTL(ttl) ((((ttl) - 2) * 4) / 5)
+
#define MaxUnansweredQueries 4
// SameResourceRecordSignature returns true if two resources records have the same name, type, and class, and may be sent
#define SameResourceRecordSignature(A,B) (A)->resrec.rrtype == (B)->resrec.rrtype && SameResourceRecordNameClassInterface((A),(B))
mDNSlocal mDNSBool SameResourceRecordNameClassInterface(const AuthRecord *const r1, const AuthRecord *const r2)
- {
- if (!r1) { LogMsg("SameResourceRecordSignature ERROR: r1 is NULL"); return(mDNSfalse); }
- if (!r2) { LogMsg("SameResourceRecordSignature ERROR: r2 is NULL"); return(mDNSfalse); }
- if (r1->resrec.InterfaceID &&
- r2->resrec.InterfaceID &&
- r1->resrec.InterfaceID != r2->resrec.InterfaceID) return(mDNSfalse);
- return(mDNSBool)(
- r1->resrec.rrclass == r2->resrec.rrclass &&
- r1->resrec.namehash == r2->resrec.namehash &&
- SameDomainName(r1->resrec.name, r2->resrec.name));
- }
+{
+ if (!r1) { LogMsg("SameResourceRecordSignature ERROR: r1 is NULL"); return(mDNSfalse); }
+ if (!r2) { LogMsg("SameResourceRecordSignature ERROR: r2 is NULL"); return(mDNSfalse); }
+ if (r1->resrec.InterfaceID &&
+ r2->resrec.InterfaceID &&
+ r1->resrec.InterfaceID != r2->resrec.InterfaceID) return(mDNSfalse);
+ return (mDNSBool)(
+ r1->resrec.rrclass == r2->resrec.rrclass &&
+ r1->resrec.namehash == r2->resrec.namehash &&
+ SameDomainName(r1->resrec.name, r2->resrec.name));
+}
// PacketRRMatchesSignature behaves as SameResourceRecordSignature, except that types may differ if our
// authoratative record is unique (as opposed to shared). For unique records, we are supposed to have
// For now, to make it easier to avoid false conflicts, we treat SPS Proxy records like shared records,
// and require the rrtypes to match for the rdata to be considered potentially conflicting
mDNSlocal mDNSBool PacketRRMatchesSignature(const CacheRecord *const pktrr, const AuthRecord *const authrr)
- {
- if (!pktrr) { LogMsg("PacketRRMatchesSignature ERROR: pktrr is NULL"); return(mDNSfalse); }
- if (!authrr) { LogMsg("PacketRRMatchesSignature ERROR: authrr is NULL"); return(mDNSfalse); }
- if (pktrr->resrec.InterfaceID &&
- authrr->resrec.InterfaceID &&
- pktrr->resrec.InterfaceID != authrr->resrec.InterfaceID) return(mDNSfalse);
- if (!(authrr->resrec.RecordType & kDNSRecordTypeUniqueMask) || authrr->WakeUp.HMAC.l[0])
- if (pktrr->resrec.rrtype != authrr->resrec.rrtype) return(mDNSfalse);
- return(mDNSBool)(
- pktrr->resrec.rrclass == authrr->resrec.rrclass &&
- pktrr->resrec.namehash == authrr->resrec.namehash &&
- SameDomainName(pktrr->resrec.name, authrr->resrec.name));
- }
+{
+ if (!pktrr) { LogMsg("PacketRRMatchesSignature ERROR: pktrr is NULL"); return(mDNSfalse); }
+ if (!authrr) { LogMsg("PacketRRMatchesSignature ERROR: authrr is NULL"); return(mDNSfalse); }
+ if (pktrr->resrec.InterfaceID &&
+ authrr->resrec.InterfaceID &&
+ pktrr->resrec.InterfaceID != authrr->resrec.InterfaceID) return(mDNSfalse);
+ if (!(authrr->resrec.RecordType & kDNSRecordTypeUniqueMask) || authrr->WakeUp.HMAC.l[0])
+ if (pktrr->resrec.rrtype != authrr->resrec.rrtype) return(mDNSfalse);
+ return (mDNSBool)(
+ pktrr->resrec.rrclass == authrr->resrec.rrclass &&
+ pktrr->resrec.namehash == authrr->resrec.namehash &&
+ SameDomainName(pktrr->resrec.name, authrr->resrec.name));
+}
// CacheRecord *ka is the CacheRecord from the known answer list in the query.
// This is the information that the requester believes to be correct.
// (either the record is non-specific, or it is specific to this interface)
// so now we just need to check the name, type, class, rdata and TTL.
mDNSlocal mDNSBool ShouldSuppressKnownAnswer(const CacheRecord *const ka, const AuthRecord *const rr)
- {
- // If RR signature is different, or data is different, then don't suppress our answer
- if (!IdenticalResourceRecord(&ka->resrec, &rr->resrec)) return(mDNSfalse);
-
- // If the requester's indicated TTL is less than half the real TTL,
- // we need to give our answer before the requester's copy expires.
- // If the requester's indicated TTL is at least half the real TTL,
- // then we can suppress our answer this time.
- // If the requester's indicated TTL is greater than the TTL we believe,
- // then that's okay, and we don't need to do anything about it.
- // (If two responders on the network are offering the same information,
- // that's okay, and if they are offering the information with different TTLs,
- // the one offering the lower TTL should defer to the one offering the higher TTL.)
- return(mDNSBool)(ka->resrec.rroriginalttl >= rr->resrec.rroriginalttl / 2);
- }
+{
+ // If RR signature is different, or data is different, then don't suppress our answer
+ if (!IdenticalResourceRecord(&ka->resrec, &rr->resrec)) return(mDNSfalse);
+
+ // If the requester's indicated TTL is less than half the real TTL,
+ // we need to give our answer before the requester's copy expires.
+ // If the requester's indicated TTL is at least half the real TTL,
+ // then we can suppress our answer this time.
+ // If the requester's indicated TTL is greater than the TTL we believe,
+ // then that's okay, and we don't need to do anything about it.
+ // (If two responders on the network are offering the same information,
+ // that's okay, and if they are offering the information with different TTLs,
+ // the one offering the lower TTL should defer to the one offering the higher TTL.)
+ return (mDNSBool)(ka->resrec.rroriginalttl >= rr->resrec.rroriginalttl / 2);
+}
mDNSlocal void SetNextAnnounceProbeTime(mDNS *const m, const AuthRecord *const rr)
- {
- if (rr->resrec.RecordType == kDNSRecordTypeUnique)
- {
- if ((rr->LastAPTime + rr->ThisAPInterval) - m->timenow > mDNSPlatformOneSecond * 10)
- {
- LogMsg("SetNextAnnounceProbeTime: ProbeCount %d Next in %d %s", rr->ProbeCount, (rr->LastAPTime + rr->ThisAPInterval) - m->timenow, ARDisplayString(m, rr));
- LogMsg("SetNextAnnounceProbeTime: m->SuppressProbes %d m->timenow %d diff %d", m->SuppressProbes, m->timenow, m->SuppressProbes - m->timenow);
- }
- if (m->NextScheduledProbe - (rr->LastAPTime + rr->ThisAPInterval) >= 0)
- m->NextScheduledProbe = (rr->LastAPTime + rr->ThisAPInterval);
- // Some defensive code:
- // If (rr->LastAPTime + rr->ThisAPInterval) happens to be far in the past, we don't want to allow
- // NextScheduledProbe to be set excessively in the past, because that can cause bad things to happen.
- // See: <rdar://problem/7795434> mDNS: Sometimes advertising stops working and record interval is set to zero
- if (m->NextScheduledProbe - m->timenow < 0)
- m->NextScheduledProbe = m->timenow;
- }
- else if (rr->AnnounceCount && (ResourceRecordIsValidAnswer(rr) || rr->resrec.RecordType == kDNSRecordTypeDeregistering))
- {
- if (m->NextScheduledResponse - (rr->LastAPTime + rr->ThisAPInterval) >= 0)
- m->NextScheduledResponse = (rr->LastAPTime + rr->ThisAPInterval);
- }
- }
+{
+ if (rr->resrec.RecordType == kDNSRecordTypeUnique)
+ {
+ if ((rr->LastAPTime + rr->ThisAPInterval) - m->timenow > mDNSPlatformOneSecond * 10)
+ {
+ LogMsg("SetNextAnnounceProbeTime: ProbeCount %d Next in %d %s", rr->ProbeCount, (rr->LastAPTime + rr->ThisAPInterval) - m->timenow, ARDisplayString(m, rr));
+ LogMsg("SetNextAnnounceProbeTime: m->SuppressProbes %d m->timenow %d diff %d", m->SuppressProbes, m->timenow, m->SuppressProbes - m->timenow);
+ }
+ if (m->NextScheduledProbe - (rr->LastAPTime + rr->ThisAPInterval) >= 0)
+ m->NextScheduledProbe = (rr->LastAPTime + rr->ThisAPInterval);
+ // Some defensive code:
+ // If (rr->LastAPTime + rr->ThisAPInterval) happens to be far in the past, we don't want to allow
+ // NextScheduledProbe to be set excessively in the past, because that can cause bad things to happen.
+ // See: <rdar://problem/7795434> mDNS: Sometimes advertising stops working and record interval is set to zero
+ if (m->NextScheduledProbe - m->timenow < 0)
+ m->NextScheduledProbe = m->timenow;
+ }
+ else if (rr->AnnounceCount && (ResourceRecordIsValidAnswer(rr) || rr->resrec.RecordType == kDNSRecordTypeDeregistering))
+ {
+ if (m->NextScheduledResponse - (rr->LastAPTime + rr->ThisAPInterval) >= 0)
+ m->NextScheduledResponse = (rr->LastAPTime + rr->ThisAPInterval);
+ }
+}
mDNSlocal void InitializeLastAPTime(mDNS *const m, AuthRecord *const rr)
- {
- // For reverse-mapping Sleep Proxy PTR records, probe interval is one second
- rr->ThisAPInterval = rr->AddressProxy.type ? mDNSPlatformOneSecond : DefaultAPIntervalForRecordType(rr->resrec.RecordType);
-
- // * If this is a record type that's going to probe, then we use the m->SuppressProbes time.
- // * Otherwise, if it's not going to probe, but m->SuppressProbes is set because we have other
- // records that are going to probe, then we delay its first announcement so that it will
- // go out synchronized with the first announcement for the other records that *are* probing.
- // This is a minor performance tweak that helps keep groups of related records synchronized together.
- // The addition of "interval / 2" is to make sure that, in the event that any of the probes are
- // delayed by a few milliseconds, this announcement does not inadvertently go out *before* the probing is complete.
- // When the probing is complete and those records begin to announce, these records will also be picked up and accelerated,
- // because they will meet the criterion of being at least half-way to their scheduled announcement time.
- // * If it's not going to probe and m->SuppressProbes is not already set then we should announce immediately.
-
- if (rr->ProbeCount)
- {
- // If we have no probe suppression time set, or it is in the past, set it now
- if (m->SuppressProbes == 0 || m->SuppressProbes - m->timenow < 0)
- {
- // To allow us to aggregate probes when a group of services are registered together,
- // the first probe is delayed 1/4 second. This means the common-case behaviour is:
- // 1/4 second wait; probe
- // 1/4 second wait; probe
- // 1/4 second wait; probe
- // 1/4 second wait; announce (i.e. service is normally announced exactly one second after being registered)
- m->SuppressProbes = NonZeroTime(m->timenow + DefaultProbeIntervalForTypeUnique/2 + mDNSRandom(DefaultProbeIntervalForTypeUnique/2));
-
- // If we already have a *probe* scheduled to go out sooner, then use that time to get better aggregation
- if (m->SuppressProbes - m->NextScheduledProbe >= 0)
- m->SuppressProbes = NonZeroTime(m->NextScheduledProbe);
- if (m->SuppressProbes - m->timenow < 0) // Make sure we don't set m->SuppressProbes excessively in the past
- m->SuppressProbes = m->timenow;
-
- // If we already have a *query* scheduled to go out sooner, then use that time to get better aggregation
- if (m->SuppressProbes - m->NextScheduledQuery >= 0)
- m->SuppressProbes = NonZeroTime(m->NextScheduledQuery);
- if (m->SuppressProbes - m->timenow < 0) // Make sure we don't set m->SuppressProbes excessively in the past
- m->SuppressProbes = m->timenow;
-
- // except... don't expect to be able to send before the m->SuppressSending timer fires
- if (m->SuppressSending && m->SuppressProbes - m->SuppressSending < 0)
- m->SuppressProbes = NonZeroTime(m->SuppressSending);
-
- if (m->SuppressProbes - m->timenow > mDNSPlatformOneSecond * 8)
- {
- LogMsg("InitializeLastAPTime ERROR m->SuppressProbes %d m->NextScheduledProbe %d m->NextScheduledQuery %d m->SuppressSending %d %d",
- m->SuppressProbes - m->timenow,
- m->NextScheduledProbe - m->timenow,
- m->NextScheduledQuery - m->timenow,
- m->SuppressSending,
- m->SuppressSending - m->timenow);
- m->SuppressProbes = NonZeroTime(m->timenow + DefaultProbeIntervalForTypeUnique/2 + mDNSRandom(DefaultProbeIntervalForTypeUnique/2));
- }
- }
- rr->LastAPTime = m->SuppressProbes - rr->ThisAPInterval;
- }
- else if (m->SuppressProbes && m->SuppressProbes - m->timenow >= 0)
- rr->LastAPTime = m->SuppressProbes - rr->ThisAPInterval + DefaultProbeIntervalForTypeUnique * DefaultProbeCountForTypeUnique + rr->ThisAPInterval / 2;
- else
- rr->LastAPTime = m->timenow - rr->ThisAPInterval;
-
- // For reverse-mapping Sleep Proxy PTR records we don't want to start probing instantly -- we
- // wait one second to give the client a chance to go to sleep, and then start our ARP/NDP probing.
- // After three probes one second apart with no answer, we conclude the client is now sleeping
- // and we can begin broadcasting our announcements to take over ownership of that IP address.
- // If we don't wait for the client to go to sleep, then when the client sees our ARP Announcements there's a risk
- // (depending on the OS and networking stack it's using) that it might interpret it as a conflict and change its IP address.
- if (rr->AddressProxy.type) rr->LastAPTime = m->timenow;
-
- // Unsolicited Neighbor Advertisements (RFC 2461 Section 7.2.6) give us fast address cache updating,
- // but some older IPv6 clients get confused by them, so for now we don't send them. Without Unsolicited
- // Neighbor Advertisements we have to rely on Neighbor Unreachability Detection instead, which is slower.
- // Given this, we'll do our best to wake for existing IPv6 connections, but we don't want to encourage
- // new ones for sleeping clients, so we'll we send deletions for our SPS clients' AAAA records.
- if (m->KnownBugs & mDNS_KnownBug_LimitedIPv6)
- if (rr->WakeUp.HMAC.l[0] && rr->resrec.rrtype == kDNSType_AAAA)
- rr->LastAPTime = m->timenow - rr->ThisAPInterval + mDNSPlatformOneSecond * 10;
-
- // Set LastMCTime to now, to inhibit multicast responses
- // (no need to send additional multicast responses when we're announcing anyway)
- rr->LastMCTime = m->timenow;
- rr->LastMCInterface = mDNSInterfaceMark;
-
- SetNextAnnounceProbeTime(m, rr);
- }
+{
+ // For reverse-mapping Sleep Proxy PTR records, probe interval is one second
+ rr->ThisAPInterval = rr->AddressProxy.type ? mDNSPlatformOneSecond : DefaultAPIntervalForRecordType(rr->resrec.RecordType);
+
+ // * If this is a record type that's going to probe, then we use the m->SuppressProbes time.
+ // * Otherwise, if it's not going to probe, but m->SuppressProbes is set because we have other
+ // records that are going to probe, then we delay its first announcement so that it will
+ // go out synchronized with the first announcement for the other records that *are* probing.
+ // This is a minor performance tweak that helps keep groups of related records synchronized together.
+ // The addition of "interval / 2" is to make sure that, in the event that any of the probes are
+ // delayed by a few milliseconds, this announcement does not inadvertently go out *before* the probing is complete.
+ // When the probing is complete and those records begin to announce, these records will also be picked up and accelerated,
+ // because they will meet the criterion of being at least half-way to their scheduled announcement time.
+ // * If it's not going to probe and m->SuppressProbes is not already set then we should announce immediately.
+
+ if (rr->ProbeCount)
+ {
+ // If we have no probe suppression time set, or it is in the past, set it now
+ if (m->SuppressProbes == 0 || m->SuppressProbes - m->timenow < 0)
+ {
+ // To allow us to aggregate probes when a group of services are registered together,
+ // the first probe is delayed 1/4 second. This means the common-case behaviour is:
+ // 1/4 second wait; probe
+ // 1/4 second wait; probe
+ // 1/4 second wait; probe
+ // 1/4 second wait; announce (i.e. service is normally announced exactly one second after being registered)
+ m->SuppressProbes = NonZeroTime(m->timenow + DefaultProbeIntervalForTypeUnique/2 + mDNSRandom(DefaultProbeIntervalForTypeUnique/2));
+
+ // If we already have a *probe* scheduled to go out sooner, then use that time to get better aggregation
+ if (m->SuppressProbes - m->NextScheduledProbe >= 0)
+ m->SuppressProbes = NonZeroTime(m->NextScheduledProbe);
+ if (m->SuppressProbes - m->timenow < 0) // Make sure we don't set m->SuppressProbes excessively in the past
+ m->SuppressProbes = m->timenow;
+
+ // If we already have a *query* scheduled to go out sooner, then use that time to get better aggregation
+ if (m->SuppressProbes - m->NextScheduledQuery >= 0)
+ m->SuppressProbes = NonZeroTime(m->NextScheduledQuery);
+ if (m->SuppressProbes - m->timenow < 0) // Make sure we don't set m->SuppressProbes excessively in the past
+ m->SuppressProbes = m->timenow;
+
+ // except... don't expect to be able to send before the m->SuppressSending timer fires
+ if (m->SuppressSending && m->SuppressProbes - m->SuppressSending < 0)
+ m->SuppressProbes = NonZeroTime(m->SuppressSending);
+
+ if (m->SuppressProbes - m->timenow > mDNSPlatformOneSecond * 8)
+ {
+ LogMsg("InitializeLastAPTime ERROR m->SuppressProbes %d m->NextScheduledProbe %d m->NextScheduledQuery %d m->SuppressSending %d %d",
+ m->SuppressProbes - m->timenow,
+ m->NextScheduledProbe - m->timenow,
+ m->NextScheduledQuery - m->timenow,
+ m->SuppressSending,
+ m->SuppressSending - m->timenow);
+ m->SuppressProbes = NonZeroTime(m->timenow + DefaultProbeIntervalForTypeUnique/2 + mDNSRandom(DefaultProbeIntervalForTypeUnique/2));
+ }
+ }
+ rr->LastAPTime = m->SuppressProbes - rr->ThisAPInterval;
+ }
+ else if (m->SuppressProbes && m->SuppressProbes - m->timenow >= 0)
+ rr->LastAPTime = m->SuppressProbes - rr->ThisAPInterval + DefaultProbeIntervalForTypeUnique * DefaultProbeCountForTypeUnique + rr->ThisAPInterval / 2;
+ else
+ rr->LastAPTime = m->timenow - rr->ThisAPInterval;
+
+ // For reverse-mapping Sleep Proxy PTR records we don't want to start probing instantly -- we
+ // wait one second to give the client a chance to go to sleep, and then start our ARP/NDP probing.
+ // After three probes one second apart with no answer, we conclude the client is now sleeping
+ // and we can begin broadcasting our announcements to take over ownership of that IP address.
+ // If we don't wait for the client to go to sleep, then when the client sees our ARP Announcements there's a risk
+ // (depending on the OS and networking stack it's using) that it might interpret it as a conflict and change its IP address.
+ if (rr->AddressProxy.type)
+ rr->LastAPTime = m->timenow;
+
+ // Set LastMCTime to now, to inhibit multicast responses
+ // (no need to send additional multicast responses when we're announcing anyway)
+ rr->LastMCTime = m->timenow;
+ rr->LastMCInterface = mDNSInterfaceMark;
+
+ SetNextAnnounceProbeTime(m, rr);
+}
mDNSlocal const domainname *SetUnicastTargetToHostName(mDNS *const m, AuthRecord *rr)
- {
- const domainname *target;
- if (rr->AutoTarget)
- {
- // For autotunnel services pointing at our IPv6 ULA we don't need or want a NAT mapping, but for all other
- // advertised services referencing our uDNS hostname, we want NAT mappings automatically created as appropriate,
- // with the port number in our advertised SRV record automatically tracking the external mapped port.
- DomainAuthInfo *AuthInfo = GetAuthInfoForName_internal(m, rr->resrec.name);
- if (!AuthInfo || !AuthInfo->AutoTunnel) rr->AutoTarget = Target_AutoHostAndNATMAP;
- }
-
- target = GetServiceTarget(m, rr);
- if (!target || target->c[0] == 0)
- {
- // defer registration until we've got a target
- LogInfo("SetUnicastTargetToHostName No target for %s", ARDisplayString(m, rr));
- rr->state = regState_NoTarget;
- return mDNSNULL;
- }
- else
- {
- LogInfo("SetUnicastTargetToHostName target %##s for resource record %s", target->c, ARDisplayString(m,rr));
- return target;
- }
- }
+{
+ const domainname *target;
+ if (rr->AutoTarget)
+ {
+ // For autotunnel services pointing at our IPv6 ULA we don't need or want a NAT mapping, but for all other
+ // advertised services referencing our uDNS hostname, we want NAT mappings automatically created as appropriate,
+ // with the port number in our advertised SRV record automatically tracking the external mapped port.
+ DomainAuthInfo *AuthInfo = GetAuthInfoForName_internal(m, rr->resrec.name);
+ if (!AuthInfo || !AuthInfo->AutoTunnel) rr->AutoTarget = Target_AutoHostAndNATMAP;
+ }
+
+ target = GetServiceTarget(m, rr);
+ if (!target || target->c[0] == 0)
+ {
+ // defer registration until we've got a target
+ LogInfo("SetUnicastTargetToHostName No target for %s", ARDisplayString(m, rr));
+ rr->state = regState_NoTarget;
+ return mDNSNULL;
+ }
+ else
+ {
+ LogInfo("SetUnicastTargetToHostName target %##s for resource record %s", target->c, ARDisplayString(m,rr));
+ return target;
+ }
+}
// Right now this only applies to mDNS (.local) services where the target host is always m->MulticastHostname
// Eventually we should unify this with GetServiceTarget() in uDNS.c
mDNSlocal void SetTargetToHostName(mDNS *const m, AuthRecord *const rr)
- {
- domainname *const target = GetRRDomainNameTarget(&rr->resrec);
- const domainname *newname = &m->MulticastHostname;
+{
+ domainname *const target = GetRRDomainNameTarget(&rr->resrec);
+ const domainname *newname = &m->MulticastHostname;
- if (!target) LogInfo("SetTargetToHostName: Don't know how to set the target of rrtype %s", DNSTypeName(rr->resrec.rrtype));
+ if (!target) LogInfo("SetTargetToHostName: Don't know how to set the target of rrtype %s", DNSTypeName(rr->resrec.rrtype));
- if (!(rr->ForceMCast || rr->ARType == AuthRecordLocalOnly || rr->ARType == AuthRecordP2P || IsLocalDomain(&rr->namestorage)))
- {
- const domainname *const n = SetUnicastTargetToHostName(m, rr);
- if (n) newname = n;
- else { target->c[0] = 0; SetNewRData(&rr->resrec, mDNSNULL, 0); return; }
- }
+ if (!(rr->ForceMCast || rr->ARType == AuthRecordLocalOnly || rr->ARType == AuthRecordP2P || IsLocalDomain(&rr->namestorage)))
+ {
+ const domainname *const n = SetUnicastTargetToHostName(m, rr);
+ if (n) newname = n;
+ else { target->c[0] = 0; SetNewRData(&rr->resrec, mDNSNULL, 0); return; }
+ }
- if (target && SameDomainName(target, newname))
- debugf("SetTargetToHostName: Target of %##s is already %##s", rr->resrec.name->c, target->c);
-
- if (target && !SameDomainName(target, newname))
- {
- AssignDomainName(target, newname);
- SetNewRData(&rr->resrec, mDNSNULL, 0); // Update rdlength, rdestimate, rdatahash
-
- // If we're in the middle of probing this record, we need to start again,
- // because changing its rdata may change the outcome of the tie-breaker.
- // (If the record type is kDNSRecordTypeUnique (unconfirmed unique) then DefaultProbeCountForRecordType is non-zero.)
- rr->ProbeCount = DefaultProbeCountForRecordType(rr->resrec.RecordType);
-
- // If we've announced this record, we really should send a goodbye packet for the old rdata before
- // changing to the new rdata. However, in practice, we only do SetTargetToHostName for unique records,
- // so when we announce them we'll set the kDNSClass_UniqueRRSet and clear any stale data that way.
- if (rr->RequireGoodbye && rr->resrec.RecordType == kDNSRecordTypeShared)
- debugf("Have announced shared record %##s (%s) at least once: should have sent a goodbye packet before updating",
- rr->resrec.name->c, DNSTypeName(rr->resrec.rrtype));
-
- rr->AnnounceCount = InitialAnnounceCount;
- rr->RequireGoodbye = mDNSfalse;
- InitializeLastAPTime(m, rr);
- }
- }
+ if (target && SameDomainName(target, newname))
+ debugf("SetTargetToHostName: Target of %##s is already %##s", rr->resrec.name->c, target->c);
+
+ if (target && !SameDomainName(target, newname))
+ {
+ AssignDomainName(target, newname);
+ SetNewRData(&rr->resrec, mDNSNULL, 0); // Update rdlength, rdestimate, rdatahash
+
+ // If we're in the middle of probing this record, we need to start again,
+ // because changing its rdata may change the outcome of the tie-breaker.
+ // (If the record type is kDNSRecordTypeUnique (unconfirmed unique) then DefaultProbeCountForRecordType is non-zero.)
+ rr->ProbeCount = DefaultProbeCountForRecordType(rr->resrec.RecordType);
+
+ // If we've announced this record, we really should send a goodbye packet for the old rdata before
+ // changing to the new rdata. However, in practice, we only do SetTargetToHostName for unique records,
+ // so when we announce them we'll set the kDNSClass_UniqueRRSet and clear any stale data that way.
+ if (rr->RequireGoodbye && rr->resrec.RecordType == kDNSRecordTypeShared)
+ debugf("Have announced shared record %##s (%s) at least once: should have sent a goodbye packet before updating",
+ rr->resrec.name->c, DNSTypeName(rr->resrec.rrtype));
+
+ rr->AnnounceCount = InitialAnnounceCount;
+ rr->RequireGoodbye = mDNSfalse;
+ rr->ProbeRestartCount = 0;
+ InitializeLastAPTime(m, rr);
+ }
+}
mDNSlocal void AcknowledgeRecord(mDNS *const m, AuthRecord *const rr)
- {
- if (rr->RecordCallback)
- {
- // CAUTION: MUST NOT do anything more with rr after calling rr->Callback(), because the client's callback function
- // is allowed to do anything, including starting/stopping queries, registering/deregistering records, etc.
- rr->Acknowledged = mDNStrue;
- mDNS_DropLockBeforeCallback(); // Allow client to legally make mDNS API calls from the callback
- rr->RecordCallback(m, rr, mStatus_NoError);
- mDNS_ReclaimLockAfterCallback(); // Decrement mDNS_reentrancy to block mDNS API calls again
- }
- }
+{
+ if (rr->RecordCallback)
+ {
+ // CAUTION: MUST NOT do anything more with rr after calling rr->Callback(), because the client's callback function
+ // is allowed to do anything, including starting/stopping queries, registering/deregistering records, etc.
+ rr->Acknowledged = mDNStrue;
+ mDNS_DropLockBeforeCallback(); // Allow client to legally make mDNS API calls from the callback
+ rr->RecordCallback(m, rr, mStatus_NoError);
+ mDNS_ReclaimLockAfterCallback(); // Decrement mDNS_reentrancy to block mDNS API calls again
+ }
+}
mDNSexport void ActivateUnicastRegistration(mDNS *const m, AuthRecord *const rr)
- {
- // Make sure that we don't activate the SRV record and associated service records, if it is in
- // NoTarget state. First time when a service is being instantiated, SRV record may be in NoTarget state.
- // We should not activate any of the other reords (PTR, TXT) that are part of the service. When
- // the target becomes available, the records will be reregistered.
- if (rr->resrec.rrtype != kDNSType_SRV)
- {
- AuthRecord *srvRR = mDNSNULL;
- if (rr->resrec.rrtype == kDNSType_PTR)
- srvRR = rr->Additional1;
- else if (rr->resrec.rrtype == kDNSType_TXT)
- srvRR = rr->DependentOn;
- if (srvRR)
- {
- if (srvRR->resrec.rrtype != kDNSType_SRV)
- {
- LogMsg("ActivateUnicastRegistration: ERROR!! Resource record %s wrong, expecting SRV type", ARDisplayString(m, srvRR));
- }
- else
- {
- LogInfo("ActivateUnicastRegistration: Found Service Record %s in state %d for %##s (%s)",
- ARDisplayString(m, srvRR), srvRR->state, rr->resrec.name->c, DNSTypeName(rr->resrec.rrtype));
- rr->state = srvRR->state;
- }
- }
- }
-
- if (rr->state == regState_NoTarget)
- {
- LogInfo("ActivateUnicastRegistration record %s in regState_NoTarget, not activating", ARDisplayString(m, rr));
- return;
- }
- // When we wake up from sleep, we call ActivateUnicastRegistration. It is possible that just before we went to sleep,
- // the service/record was being deregistered. In that case, we should not try to register again. For the cases where
- // the records are deregistered due to e.g., no target for the SRV record, we would have returned from above if it
- // was already in NoTarget state. If it was in the process of deregistration but did not complete fully before we went
- // to sleep, then it is okay to start in Pending state as we will go back to NoTarget state if we don't have a target.
- if (rr->resrec.RecordType == kDNSRecordTypeDeregistering)
- {
- LogInfo("ActivateUnicastRegistration: Resource record %s, current state %d, moving to DeregPending", ARDisplayString(m, rr), rr->state);
- rr->state = regState_DeregPending;
- }
- else
- {
- LogInfo("ActivateUnicastRegistration: Resource record %s, current state %d, moving to Pending", ARDisplayString(m, rr), rr->state);
- rr->state = regState_Pending;
- }
- rr->ProbeCount = 0;
- rr->AnnounceCount = 0;
- rr->ThisAPInterval = INIT_RECORD_REG_INTERVAL;
- rr->LastAPTime = m->timenow - rr->ThisAPInterval;
- rr->expire = 0; // Forget about all the leases, start fresh
- rr->uselease = mDNStrue;
- rr->updateid = zeroID;
- rr->SRVChanged = mDNSfalse;
- rr->updateError = mStatus_NoError;
- // RestartRecordGetZoneData calls this function whenever a new interface gets registered with core.
- // The records might already be registered with the server and hence could have NAT state.
- if (rr->NATinfo.clientContext)
- {
- mDNS_StopNATOperation_internal(m, &rr->NATinfo);
- rr->NATinfo.clientContext = mDNSNULL;
- }
- if (rr->nta) { CancelGetZoneData(m, rr->nta); rr->nta = mDNSNULL; }
- if (rr->tcp) { DisposeTCPConn(rr->tcp); rr->tcp = mDNSNULL; }
- if (m->NextuDNSEvent - (rr->LastAPTime + rr->ThisAPInterval) >= 0)
- m->NextuDNSEvent = (rr->LastAPTime + rr->ThisAPInterval);
- }
+{
+ // Make sure that we don't activate the SRV record and associated service records, if it is in
+ // NoTarget state. First time when a service is being instantiated, SRV record may be in NoTarget state.
+ // We should not activate any of the other reords (PTR, TXT) that are part of the service. When
+ // the target becomes available, the records will be reregistered.
+ if (rr->resrec.rrtype != kDNSType_SRV)
+ {
+ AuthRecord *srvRR = mDNSNULL;
+ if (rr->resrec.rrtype == kDNSType_PTR)
+ srvRR = rr->Additional1;
+ else if (rr->resrec.rrtype == kDNSType_TXT)
+ srvRR = rr->DependentOn;
+ if (srvRR)
+ {
+ if (srvRR->resrec.rrtype != kDNSType_SRV)
+ {
+ LogMsg("ActivateUnicastRegistration: ERROR!! Resource record %s wrong, expecting SRV type", ARDisplayString(m, srvRR));
+ }
+ else
+ {
+ LogInfo("ActivateUnicastRegistration: Found Service Record %s in state %d for %##s (%s)",
+ ARDisplayString(m, srvRR), srvRR->state, rr->resrec.name->c, DNSTypeName(rr->resrec.rrtype));
+ rr->state = srvRR->state;
+ }
+ }
+ }
+
+ if (rr->state == regState_NoTarget)
+ {
+ LogInfo("ActivateUnicastRegistration record %s in regState_NoTarget, not activating", ARDisplayString(m, rr));
+ return;
+ }
+ // When we wake up from sleep, we call ActivateUnicastRegistration. It is possible that just before we went to sleep,
+ // the service/record was being deregistered. In that case, we should not try to register again. For the cases where
+ // the records are deregistered due to e.g., no target for the SRV record, we would have returned from above if it
+ // was already in NoTarget state. If it was in the process of deregistration but did not complete fully before we went
+ // to sleep, then it is okay to start in Pending state as we will go back to NoTarget state if we don't have a target.
+ if (rr->resrec.RecordType == kDNSRecordTypeDeregistering)
+ {
+ LogInfo("ActivateUnicastRegistration: Resource record %s, current state %d, moving to DeregPending", ARDisplayString(m, rr), rr->state);
+ rr->state = regState_DeregPending;
+ }
+ else
+ {
+ LogInfo("ActivateUnicastRegistration: Resource record %s, current state %d, moving to Pending", ARDisplayString(m, rr), rr->state);
+ rr->state = regState_Pending;
+ }
+ rr->ProbeCount = 0;
+ rr->ProbeRestartCount = 0;
+ rr->AnnounceCount = 0;
+ rr->ThisAPInterval = INIT_RECORD_REG_INTERVAL;
+ rr->LastAPTime = m->timenow - rr->ThisAPInterval;
+ rr->expire = 0; // Forget about all the leases, start fresh
+ rr->uselease = mDNStrue;
+ rr->updateid = zeroID;
+ rr->SRVChanged = mDNSfalse;
+ rr->updateError = mStatus_NoError;
+ // RestartRecordGetZoneData calls this function whenever a new interface gets registered with core.
+ // The records might already be registered with the server and hence could have NAT state.
+ if (rr->NATinfo.clientContext)
+ {
+ mDNS_StopNATOperation_internal(m, &rr->NATinfo);
+ rr->NATinfo.clientContext = mDNSNULL;
+ }
+ if (rr->nta) { CancelGetZoneData(m, rr->nta); rr->nta = mDNSNULL; }
+ if (rr->tcp) { DisposeTCPConn(rr->tcp); rr->tcp = mDNSNULL; }
+ if (m->NextuDNSEvent - (rr->LastAPTime + rr->ThisAPInterval) >= 0)
+ m->NextuDNSEvent = (rr->LastAPTime + rr->ThisAPInterval);
+}
// Two records qualify to be local duplicates if:
// (a) the RecordTypes are the same, or
// (b) one is Unique and the other Verified
// (c) either is in the process of deregistering
#define RecordLDT(A,B) ((A)->resrec.RecordType == (B)->resrec.RecordType || \
- ((A)->resrec.RecordType | (B)->resrec.RecordType) == (kDNSRecordTypeUnique | kDNSRecordTypeVerified) || \
- ((A)->resrec.RecordType == kDNSRecordTypeDeregistering || (B)->resrec.RecordType == kDNSRecordTypeDeregistering))
+ ((A)->resrec.RecordType | (B)->resrec.RecordType) == (kDNSRecordTypeUnique | kDNSRecordTypeVerified) || \
+ ((A)->resrec.RecordType == kDNSRecordTypeDeregistering || (B)->resrec.RecordType == kDNSRecordTypeDeregistering))
#define RecordIsLocalDuplicate(A,B) \
- ((A)->resrec.InterfaceID == (B)->resrec.InterfaceID && RecordLDT((A),(B)) && IdenticalResourceRecord(&(A)->resrec, &(B)->resrec))
+ ((A)->resrec.InterfaceID == (B)->resrec.InterfaceID && RecordLDT((A),(B)) && IdenticalResourceRecord(& (A)->resrec, & (B)->resrec))
mDNSlocal AuthRecord *CheckAuthIdenticalRecord(AuthHash *r, AuthRecord *rr)
- {
- AuthGroup *a;
- AuthGroup **ag = &a;
- AuthRecord **rp;
- const mDNSu32 slot = AuthHashSlot(rr->resrec.name);
-
- a = AuthGroupForRecord(r, slot, &rr->resrec);
- if (!a) return mDNSNULL;
- rp = &(*ag)->members;
- while (*rp)
- {
- if (!RecordIsLocalDuplicate(*rp, rr))
- rp=&(*rp)->next;
- else
- {
- if ((*rp)->resrec.RecordType == kDNSRecordTypeDeregistering)
- {
- (*rp)->AnnounceCount = 0;
- rp=&(*rp)->next;
- }
- else return *rp;
- }
- }
- return (mDNSNULL);
- }
+{
+ AuthGroup *a;
+ AuthGroup **ag = &a;
+ AuthRecord **rp;
+ const mDNSu32 slot = AuthHashSlot(rr->resrec.name);
+
+ a = AuthGroupForRecord(r, slot, &rr->resrec);
+ if (!a) return mDNSNULL;
+ rp = &(*ag)->members;
+ while (*rp)
+ {
+ if (!RecordIsLocalDuplicate(*rp, rr))
+ rp=&(*rp)->next;
+ else
+ {
+ if ((*rp)->resrec.RecordType == kDNSRecordTypeDeregistering)
+ {
+ (*rp)->AnnounceCount = 0;
+ rp=&(*rp)->next;
+ }
+ else return *rp;
+ }
+ }
+ return (mDNSNULL);
+}
mDNSlocal mDNSBool CheckAuthRecordConflict(AuthHash *r, AuthRecord *rr)
- {
- AuthGroup *a;
- AuthGroup **ag = &a;
- AuthRecord **rp;
- const mDNSu32 slot = AuthHashSlot(rr->resrec.name);
-
- a = AuthGroupForRecord(r, slot, &rr->resrec);
- if (!a) return mDNSfalse;
- rp = &(*ag)->members;
- while (*rp)
- {
- const AuthRecord *s1 = rr->RRSet ? rr->RRSet : rr;
- const AuthRecord *s2 = (*rp)->RRSet ? (*rp)->RRSet : *rp;
- if (s1 != s2 && SameResourceRecordSignature((*rp), rr) && !IdenticalSameNameRecord(&(*rp)->resrec, &rr->resrec))
- return mDNStrue;
- else
- rp=&(*rp)->next;
- }
- return (mDNSfalse);
- }
+{
+ AuthGroup *a;
+ AuthGroup **ag = &a;
+ AuthRecord **rp;
+ const mDNSu32 slot = AuthHashSlot(rr->resrec.name);
+
+ a = AuthGroupForRecord(r, slot, &rr->resrec);
+ if (!a) return mDNSfalse;
+ rp = &(*ag)->members;
+ while (*rp)
+ {
+ const AuthRecord *s1 = rr->RRSet ? rr->RRSet : rr;
+ const AuthRecord *s2 = (*rp)->RRSet ? (*rp)->RRSet : *rp;
+ if (s1 != s2 && SameResourceRecordSignature((*rp), rr) && !IdenticalSameNameRecord(&(*rp)->resrec, &rr->resrec))
+ return mDNStrue;
+ else
+ rp=&(*rp)->next;
+ }
+ return (mDNSfalse);
+}
// checks to see if "rr" is already present
mDNSlocal AuthRecord *CheckAuthSameRecord(AuthHash *r, AuthRecord *rr)
- {
- AuthGroup *a;
- AuthGroup **ag = &a;
- AuthRecord **rp;
- const mDNSu32 slot = AuthHashSlot(rr->resrec.name);
-
- a = AuthGroupForRecord(r, slot, &rr->resrec);
- if (!a) return mDNSNULL;
- rp = &(*ag)->members;
- while (*rp)
- {
- if (*rp != rr)
- rp=&(*rp)->next;
- else
- {
- return *rp;
- }
- }
- return (mDNSNULL);
- }
+{
+ AuthGroup *a;
+ AuthGroup **ag = &a;
+ AuthRecord **rp;
+ const mDNSu32 slot = AuthHashSlot(rr->resrec.name);
+
+ a = AuthGroupForRecord(r, slot, &rr->resrec);
+ if (!a) return mDNSNULL;
+ rp = &(*ag)->members;
+ while (*rp)
+ {
+ if (*rp != rr)
+ rp=&(*rp)->next;
+ else
+ {
+ return *rp;
+ }
+ }
+ return (mDNSNULL);
+}
+
+
+mDNSlocal void DecrementAutoTargetServices(mDNS *const m, AuthRecord *const rr)
+{
+ if (!AuthRecord_uDNS(rr) && rr->resrec.rrtype == kDNSType_SRV && rr->AutoTarget == Target_AutoHost)
+ {
+ m->AutoTargetServices--;
+ LogInfo("DecrementAutoTargetServices: AutoService Record %s, AutoTargetServices %d", ARDisplayString(m, rr), m->AutoTargetServices);
+ if (!m->AutoTargetServices)
+ DeadvertiseAllInterfaceRecords(m);
+ }
+}
+
+mDNSlocal void IncrementAutoTargetServices(mDNS *const m, AuthRecord *const rr)
+{
+ if (!AuthRecord_uDNS(rr) && rr->resrec.rrtype == kDNSType_SRV && rr->AutoTarget == Target_AutoHost)
+ {
+ int count = m->AutoTargetServices;
+
+ // Bump up before calling AdvertiseAllInterfaceRecords. AdvertiseInterface
+ // returns without doing anything if the count is zero.
+ m->AutoTargetServices++;
+ LogInfo("IncrementAutoTargetServices: AutoService Record %s, AutoTargetServices %d", ARDisplayString(m, rr), m->AutoTargetServices);
+ if (!count)
+ AdvertiseAllInterfaceRecords(m);
+ }
+}
+
+mDNSlocal void getKeepaliveRaddr(mDNS *const m, AuthRecord *rr, mDNSAddr *raddr)
+{
+ mDNSAddr laddr;
+ mDNSEthAddr eth;
+ mDNSIPPort lport, rport;
+ mDNSu32 timeout, seq, ack;
+ mDNSu16 win;
+
+ if (mDNS_KeepaliveRecord(&rr->resrec))
+ {
+ mDNS_ExtractKeepaliveInfo(rr, &timeout, &laddr, raddr, ð, &seq, &ack, &lport, &rport, &win);
+ if (!timeout || mDNSAddressIsZero(&laddr) || mDNSAddressIsZero(raddr) || mDNSIPPortIsZero(lport) || mDNSIPPortIsZero(rport))
+ {
+ LogMsg("getKeepaliveRaddr: not a valid record %s for keepalive %#a:%d %#a:%d", ARDisplayString(m, rr), &laddr, lport.NotAnInteger, raddr, rport.NotAnInteger);
+ return;
+ }
+ }
+}
// Exported so uDNS.c can call this
mDNSexport mStatus mDNS_Register_internal(mDNS *const m, AuthRecord *const rr)
- {
- domainname *target = GetRRDomainNameTarget(&rr->resrec);
- AuthRecord *r;
- AuthRecord **p = &m->ResourceRecords;
- AuthRecord **d = &m->DuplicateRecords;
+{
+ domainname *target = GetRRDomainNameTarget(&rr->resrec);
+ AuthRecord *r;
+ AuthRecord **p = &m->ResourceRecords;
+ AuthRecord **d = &m->DuplicateRecords;
- if ((mDNSs32)rr->resrec.rroriginalttl <= 0)
- { LogMsg("mDNS_Register_internal: TTL %X should be 1 - 0x7FFFFFFF %s", rr->resrec.rroriginalttl, ARDisplayString(m, rr)); return(mStatus_BadParamErr); }
+ if ((mDNSs32)rr->resrec.rroriginalttl <= 0)
+ { LogMsg("mDNS_Register_internal: TTL %X should be 1 - 0x7FFFFFFF %s", rr->resrec.rroriginalttl, ARDisplayString(m, rr)); return(mStatus_BadParamErr); }
- if (!rr->resrec.RecordType)
- { LogMsg("mDNS_Register_internal: RecordType must be non-zero %s", ARDisplayString(m, rr)); return(mStatus_BadParamErr); }
+ if (!rr->resrec.RecordType)
+ { LogMsg("mDNS_Register_internal: RecordType must be non-zero %s", ARDisplayString(m, rr)); return(mStatus_BadParamErr); }
- if (m->ShutdownTime)
- { LogMsg("mDNS_Register_internal: Shutting down, can't register %s", ARDisplayString(m, rr)); return(mStatus_ServiceNotRunning); }
-
- if (m->DivertMulticastAdvertisements && !AuthRecord_uDNS(rr))
- {
- mDNSInterfaceID previousID = rr->resrec.InterfaceID;
- if (rr->resrec.InterfaceID == mDNSInterface_Any || rr->resrec.InterfaceID == mDNSInterface_P2P)
- {
- rr->resrec.InterfaceID = mDNSInterface_LocalOnly;
- rr->ARType = AuthRecordLocalOnly;
- }
- if (rr->resrec.InterfaceID != mDNSInterface_LocalOnly)
- {
- NetworkInterfaceInfo *intf = FirstInterfaceForID(m, rr->resrec.InterfaceID);
- if (intf && !intf->Advertise){ rr->resrec.InterfaceID = mDNSInterface_LocalOnly; rr->ARType = AuthRecordLocalOnly; }
- }
- if (rr->resrec.InterfaceID != previousID)
- LogInfo("mDNS_Register_internal: Diverting record to local-only %s", ARDisplayString(m, rr));
- }
-
- if (RRLocalOnly(rr))
- {
- if (CheckAuthSameRecord(&m->rrauth, rr))
- {
- LogMsg("mDNS_Register_internal: ERROR!! Tried to register LocalOnly AuthRecord %p %##s (%s) that's already in the list",
- rr, rr->resrec.name->c, DNSTypeName(rr->resrec.rrtype));
- return(mStatus_AlreadyRegistered);
- }
- }
- else
- {
- while (*p && *p != rr) p=&(*p)->next;
- if (*p)
- {
- LogMsg("mDNS_Register_internal: ERROR!! Tried to register AuthRecord %p %##s (%s) that's already in the list",
- rr, rr->resrec.name->c, DNSTypeName(rr->resrec.rrtype));
- return(mStatus_AlreadyRegistered);
- }
- }
-
- while (*d && *d != rr) d=&(*d)->next;
- if (*d)
- {
- LogMsg("mDNS_Register_internal: ERROR!! Tried to register AuthRecord %p %##s (%s) that's already in the Duplicate list",
- rr, rr->resrec.name->c, DNSTypeName(rr->resrec.rrtype));
- return(mStatus_AlreadyRegistered);
- }
-
- if (rr->DependentOn)
- {
- if (rr->resrec.RecordType == kDNSRecordTypeUnique)
- rr->resrec.RecordType = kDNSRecordTypeVerified;
- else
- {
- LogMsg("mDNS_Register_internal: ERROR! %##s (%s): rr->DependentOn && RecordType != kDNSRecordTypeUnique",
- rr->resrec.name->c, DNSTypeName(rr->resrec.rrtype));
- return(mStatus_Invalid);
- }
- if (!(rr->DependentOn->resrec.RecordType & (kDNSRecordTypeUnique | kDNSRecordTypeVerified | kDNSRecordTypeKnownUnique)))
- {
- LogMsg("mDNS_Register_internal: ERROR! %##s (%s): rr->DependentOn->RecordType bad type %X",
- rr->resrec.name->c, DNSTypeName(rr->resrec.rrtype), rr->DependentOn->resrec.RecordType);
- return(mStatus_Invalid);
- }
- }
-
- // If this resource record is referencing a specific interface, make sure it exists.
- // Skip checks for LocalOnly and P2P as they are not valid InterfaceIDs. Also, for scoped
- // entries in /etc/hosts skip that check as that interface may not be valid at this time.
- if (rr->resrec.InterfaceID && rr->ARType != AuthRecordLocalOnly && rr->ARType != AuthRecordP2P)
- {
- NetworkInterfaceInfo *intf = FirstInterfaceForID(m, rr->resrec.InterfaceID);
- if (!intf)
- {
- debugf("mDNS_Register_internal: Bogus InterfaceID %p in resource record", rr->resrec.InterfaceID);
- return(mStatus_BadReferenceErr);
- }
- }
-
- rr->next = mDNSNULL;
-
- // Field Group 1: The actual information pertaining to this resource record
- // Set up by client prior to call
-
- // Field Group 2: Persistent metadata for Authoritative Records
+ if (m->ShutdownTime)
+ { LogMsg("mDNS_Register_internal: Shutting down, can't register %s", ARDisplayString(m, rr)); return(mStatus_ServiceNotRunning); }
+
+ if (m->DivertMulticastAdvertisements && !AuthRecord_uDNS(rr))
+ {
+ mDNSInterfaceID previousID = rr->resrec.InterfaceID;
+ if (rr->resrec.InterfaceID == mDNSInterface_Any || rr->resrec.InterfaceID == mDNSInterface_P2P)
+ {
+ rr->resrec.InterfaceID = mDNSInterface_LocalOnly;
+ rr->ARType = AuthRecordLocalOnly;
+ }
+ if (rr->resrec.InterfaceID != mDNSInterface_LocalOnly)
+ {
+ NetworkInterfaceInfo *intf = FirstInterfaceForID(m, rr->resrec.InterfaceID);
+ if (intf && !intf->Advertise) { rr->resrec.InterfaceID = mDNSInterface_LocalOnly; rr->ARType = AuthRecordLocalOnly; }
+ }
+ if (rr->resrec.InterfaceID != previousID)
+ LogInfo("mDNS_Register_internal: Diverting record to local-only %s", ARDisplayString(m, rr));
+ }
+
+ if (RRLocalOnly(rr))
+ {
+ if (CheckAuthSameRecord(&m->rrauth, rr))
+ {
+ LogMsg("mDNS_Register_internal: ERROR!! Tried to register LocalOnly AuthRecord %p %##s (%s) that's already in the list",
+ rr, rr->resrec.name->c, DNSTypeName(rr->resrec.rrtype));
+ return(mStatus_AlreadyRegistered);
+ }
+ }
+ else
+ {
+ while (*p && *p != rr) p=&(*p)->next;
+ if (*p)
+ {
+ LogMsg("mDNS_Register_internal: ERROR!! Tried to register AuthRecord %p %##s (%s) that's already in the list",
+ rr, rr->resrec.name->c, DNSTypeName(rr->resrec.rrtype));
+ return(mStatus_AlreadyRegistered);
+ }
+ }
+
+ while (*d && *d != rr) d=&(*d)->next;
+ if (*d)
+ {
+ LogMsg("mDNS_Register_internal: ERROR!! Tried to register AuthRecord %p %##s (%s) that's already in the Duplicate list",
+ rr, rr->resrec.name->c, DNSTypeName(rr->resrec.rrtype));
+ return(mStatus_AlreadyRegistered);
+ }
+
+ if (rr->DependentOn)
+ {
+ if (rr->resrec.RecordType == kDNSRecordTypeUnique)
+ rr->resrec.RecordType = kDNSRecordTypeVerified;
+ else
+ {
+ LogMsg("mDNS_Register_internal: ERROR! %##s (%s): rr->DependentOn && RecordType != kDNSRecordTypeUnique",
+ rr->resrec.name->c, DNSTypeName(rr->resrec.rrtype));
+ return(mStatus_Invalid);
+ }
+ if (!(rr->DependentOn->resrec.RecordType & (kDNSRecordTypeUnique | kDNSRecordTypeVerified | kDNSRecordTypeKnownUnique)))
+ {
+ LogMsg("mDNS_Register_internal: ERROR! %##s (%s): rr->DependentOn->RecordType bad type %X",
+ rr->resrec.name->c, DNSTypeName(rr->resrec.rrtype), rr->DependentOn->resrec.RecordType);
+ return(mStatus_Invalid);
+ }
+ }
+
+ rr->next = mDNSNULL;
+
+ // Field Group 1: The actual information pertaining to this resource record
+ // Set up by client prior to call
+
+ // Field Group 2: Persistent metadata for Authoritative Records
// rr->Additional1 = set to mDNSNULL in mDNS_SetupResourceRecord; may be overridden by client
// rr->Additional2 = set to mDNSNULL in mDNS_SetupResourceRecord; may be overridden by client
// rr->DependentOn = set to mDNSNULL in mDNS_SetupResourceRecord; may be overridden by client
// rr->RecordType = already set in mDNS_SetupResourceRecord
// rr->HostTarget = set to mDNSfalse in mDNS_SetupResourceRecord; may be overridden by client
// rr->AllowRemoteQuery = set to mDNSfalse in mDNS_SetupResourceRecord; may be overridden by client
- // Make sure target is not uninitialized data, or we may crash writing debugging log messages
- if (rr->AutoTarget && target) target->c[0] = 0;
-
- // Field Group 3: Transient state for Authoritative Records
- rr->Acknowledged = mDNSfalse;
- rr->ProbeCount = DefaultProbeCountForRecordType(rr->resrec.RecordType);
- rr->AnnounceCount = InitialAnnounceCount;
- rr->RequireGoodbye = mDNSfalse;
- rr->AnsweredLocalQ = mDNSfalse;
- rr->IncludeInProbe = mDNSfalse;
- rr->ImmedUnicast = mDNSfalse;
- rr->SendNSECNow = mDNSNULL;
- rr->ImmedAnswer = mDNSNULL;
- rr->ImmedAdditional = mDNSNULL;
- rr->SendRNow = mDNSNULL;
- rr->v4Requester = zerov4Addr;
- rr->v6Requester = zerov6Addr;
- rr->NextResponse = mDNSNULL;
- rr->NR_AnswerTo = mDNSNULL;
- rr->NR_AdditionalTo = mDNSNULL;
- if (!rr->AutoTarget) InitializeLastAPTime(m, rr);
+ // Make sure target is not uninitialized data, or we may crash writing debugging log messages
+ if (rr->AutoTarget && target) target->c[0] = 0;
+
+ // Field Group 3: Transient state for Authoritative Records
+ rr->Acknowledged = mDNSfalse;
+ rr->ProbeCount = DefaultProbeCountForRecordType(rr->resrec.RecordType);
+ rr->ProbeRestartCount = 0;
+ rr->AnnounceCount = InitialAnnounceCount;
+ rr->RequireGoodbye = mDNSfalse;
+ rr->AnsweredLocalQ = mDNSfalse;
+ rr->IncludeInProbe = mDNSfalse;
+ rr->ImmedUnicast = mDNSfalse;
+ rr->SendNSECNow = mDNSNULL;
+ rr->ImmedAnswer = mDNSNULL;
+ rr->ImmedAdditional = mDNSNULL;
+ rr->SendRNow = mDNSNULL;
+ rr->v4Requester = zerov4Addr;
+ rr->v6Requester = zerov6Addr;
+ rr->NextResponse = mDNSNULL;
+ rr->NR_AnswerTo = mDNSNULL;
+ rr->NR_AdditionalTo = mDNSNULL;
+ if (!rr->AutoTarget) InitializeLastAPTime(m, rr);
// rr->LastAPTime = Set for us in InitializeLastAPTime()
// rr->LastMCTime = Set for us in InitializeLastAPTime()
// rr->LastMCInterface = Set for us in InitializeLastAPTime()
- rr->NewRData = mDNSNULL;
- rr->newrdlength = 0;
- rr->UpdateCallback = mDNSNULL;
- rr->UpdateCredits = kMaxUpdateCredits;
- rr->NextUpdateCredit = 0;
- rr->UpdateBlocked = 0;
-
- // For records we're holding as proxy (except reverse-mapping PTR records) two announcements is sufficient
- if (rr->WakeUp.HMAC.l[0] && !rr->AddressProxy.type) rr->AnnounceCount = 2;
-
- // Field Group 4: Transient uDNS state for Authoritative Records
- rr->state = regState_Zero;
- rr->uselease = 0;
- rr->expire = 0;
- rr->Private = 0;
- rr->updateid = zeroID;
- rr->zone = rr->resrec.name;
- rr->nta = mDNSNULL;
- rr->tcp = mDNSNULL;
- rr->OrigRData = 0;
- rr->OrigRDLen = 0;
- rr->InFlightRData = 0;
- rr->InFlightRDLen = 0;
- rr->QueuedRData = 0;
- rr->QueuedRDLen = 0;
- //mDNSPlatformMemZero(&rr->NATinfo, sizeof(rr->NATinfo));
- // We should be recording the actual internal port for this service record here. Once we initiate our NAT mapping
- // request we'll subsequently overwrite srv.port with the allocated external NAT port -- potentially multiple
- // times with different values if the external NAT port changes during the lifetime of the service registration.
- //if (rr->resrec.rrtype == kDNSType_SRV) rr->NATinfo.IntPort = rr->resrec.rdata->u.srv.port;
+ rr->NewRData = mDNSNULL;
+ rr->newrdlength = 0;
+ rr->UpdateCallback = mDNSNULL;
+ rr->UpdateCredits = kMaxUpdateCredits;
+ rr->NextUpdateCredit = 0;
+ rr->UpdateBlocked = 0;
+
+ // For records we're holding as proxy (except reverse-mapping PTR records) two announcements is sufficient
+ if (rr->WakeUp.HMAC.l[0] && !rr->AddressProxy.type) rr->AnnounceCount = 2;
+
+ // Field Group 4: Transient uDNS state for Authoritative Records
+ rr->state = regState_Zero;
+ rr->uselease = 0;
+ rr->expire = 0;
+ rr->Private = 0;
+ rr->updateid = zeroID;
+ rr->updateIntID = zeroOpaque64;
+ rr->zone = rr->resrec.name;
+ rr->nta = mDNSNULL;
+ rr->tcp = mDNSNULL;
+ rr->OrigRData = 0;
+ rr->OrigRDLen = 0;
+ rr->InFlightRData = 0;
+ rr->InFlightRDLen = 0;
+ rr->QueuedRData = 0;
+ rr->QueuedRDLen = 0;
+ //mDNSPlatformMemZero(&rr->NATinfo, sizeof(rr->NATinfo));
+ // We should be recording the actual internal port for this service record here. Once we initiate our NAT mapping
+ // request we'll subsequently overwrite srv.port with the allocated external NAT port -- potentially multiple
+ // times with different values if the external NAT port changes during the lifetime of the service registration.
+ //if (rr->resrec.rrtype == kDNSType_SRV) rr->NATinfo.IntPort = rr->resrec.rdata->u.srv.port;
// rr->resrec.interface = already set in mDNS_SetupResourceRecord
// rr->resrec.name->c = MUST be set by client
// rr->resrec.rroriginalttl = already set in mDNS_SetupResourceRecord
// rr->resrec.rdata = MUST be set by client, unless record type is CNAME or PTR and rr->HostTarget is set
- // BIND named (name daemon) doesn't allow TXT records with zero-length rdata. This is strictly speaking correct,
- // since RFC 1035 specifies a TXT record as "One or more <character-string>s", not "Zero or more <character-string>s".
- // Since some legacy apps try to create zero-length TXT records, we'll silently correct it here.
- if (rr->resrec.rrtype == kDNSType_TXT && rr->resrec.rdlength == 0) { rr->resrec.rdlength = 1; rr->resrec.rdata->u.txt.c[0] = 0; }
+ // BIND named (name daemon) doesn't allow TXT records with zero-length rdata. This is strictly speaking correct,
+ // since RFC 1035 specifies a TXT record as "One or more <character-string>s", not "Zero or more <character-string>s".
+ // Since some legacy apps try to create zero-length TXT records, we'll silently correct it here.
+ if (rr->resrec.rrtype == kDNSType_TXT && rr->resrec.rdlength == 0) { rr->resrec.rdlength = 1; rr->resrec.rdata->u.txt.c[0] = 0; }
- if (rr->AutoTarget)
- {
- SetTargetToHostName(m, rr); // Also sets rdlength and rdestimate for us, and calls InitializeLastAPTime();
+ if (rr->AutoTarget)
+ {
+ SetTargetToHostName(m, rr); // Also sets rdlength and rdestimate for us, and calls InitializeLastAPTime();
#ifndef UNICAST_DISABLED
- // If we have no target record yet, SetTargetToHostName will set rr->state == regState_NoTarget
- // In this case we leave the record half-formed in the list, and later we'll remove it from the list and re-add it properly.
- if (rr->state == regState_NoTarget)
- {
- // Initialize the target so that we don't crash while logging etc.
- domainname *tar = GetRRDomainNameTarget(&rr->resrec);
- if (tar) tar->c[0] = 0;
- LogInfo("mDNS_Register_internal: record %s in NoTarget state", ARDisplayString(m, rr));
- }
+ // If we have no target record yet, SetTargetToHostName will set rr->state == regState_NoTarget
+ // In this case we leave the record half-formed in the list, and later we'll remove it from the list and re-add it properly.
+ if (rr->state == regState_NoTarget)
+ {
+ // Initialize the target so that we don't crash while logging etc.
+ domainname *tar = GetRRDomainNameTarget(&rr->resrec);
+ if (tar) tar->c[0] = 0;
+ LogInfo("mDNS_Register_internal: record %s in NoTarget state", ARDisplayString(m, rr));
+ }
#endif
- }
- else
- {
- rr->resrec.rdlength = GetRDLength(&rr->resrec, mDNSfalse);
- rr->resrec.rdestimate = GetRDLength(&rr->resrec, mDNStrue);
- }
+ }
+ else
+ {
+ rr->resrec.rdlength = GetRDLength(&rr->resrec, mDNSfalse);
+ rr->resrec.rdestimate = GetRDLength(&rr->resrec, mDNStrue);
+ }
- if (!ValidateDomainName(rr->resrec.name))
- { LogMsg("Attempt to register record with invalid name: %s", ARDisplayString(m, rr)); return(mStatus_Invalid); }
+ if (!ValidateDomainName(rr->resrec.name))
+ { LogMsg("Attempt to register record with invalid name: %s", ARDisplayString(m, rr)); return(mStatus_Invalid); }
- // Don't do this until *after* we've set rr->resrec.rdlength
- if (!ValidateRData(rr->resrec.rrtype, rr->resrec.rdlength, rr->resrec.rdata))
- { LogMsg("Attempt to register record with invalid rdata: %s", ARDisplayString(m, rr)); return(mStatus_Invalid); }
+ // Don't do this until *after* we've set rr->resrec.rdlength
+ if (!ValidateRData(rr->resrec.rrtype, rr->resrec.rdlength, rr->resrec.rdata))
+ { LogMsg("Attempt to register record with invalid rdata: %s", ARDisplayString(m, rr)); return(mStatus_Invalid); }
- rr->resrec.namehash = DomainNameHashValue(rr->resrec.name);
- rr->resrec.rdatahash = target ? DomainNameHashValue(target) : RDataHashValue(&rr->resrec);
-
- if (RRLocalOnly(rr))
- {
- // If this is supposed to be unique, make sure we don't have any name conflicts.
- // If we found a conflict, we may still want to insert the record in the list but mark it appropriately
- // (kDNSRecordTypeDeregistering) so that we deliver RMV events to the application. But this causes more
- // complications and not clear whether there are any benefits. See rdar:9304275 for details.
- // Hence, just bail out.
- if (rr->resrec.RecordType & kDNSRecordTypeUniqueMask)
- {
- if (CheckAuthRecordConflict(&m->rrauth, rr))
- {
- LogInfo("mDNS_Register_internal: Name conflict %s (%p), InterfaceID %p", ARDisplayString(m, rr), rr, rr->resrec.InterfaceID);
- return mStatus_NameConflict;
- }
- }
- }
-
- // For uDNS records, we don't support duplicate checks at this time.
+ rr->resrec.namehash = DomainNameHashValue(rr->resrec.name);
+ rr->resrec.rdatahash = target ? DomainNameHashValue(target) : RDataHashValue(&rr->resrec);
+
+ if (RRLocalOnly(rr))
+ {
+ // If this is supposed to be unique, make sure we don't have any name conflicts.
+ // If we found a conflict, we may still want to insert the record in the list but mark it appropriately
+ // (kDNSRecordTypeDeregistering) so that we deliver RMV events to the application. But this causes more
+ // complications and not clear whether there are any benefits. See rdar:9304275 for details.
+ // Hence, just bail out.
+ if (rr->resrec.RecordType & kDNSRecordTypeUniqueMask)
+ {
+ if (CheckAuthRecordConflict(&m->rrauth, rr))
+ {
+ LogInfo("mDNS_Register_internal: Name conflict %s (%p), InterfaceID %p", ARDisplayString(m, rr), rr, rr->resrec.InterfaceID);
+ return mStatus_NameConflict;
+ }
+ }
+ }
+
+ // For uDNS records, we don't support duplicate checks at this time.
#ifndef UNICAST_DISABLED
- if (AuthRecord_uDNS(rr))
- {
- if (!m->NewLocalRecords) m->NewLocalRecords = rr;
- // When we called SetTargetToHostName, it may have caused mDNS_Register_internal to be re-entered, appending new
- // records to the list, so we now need to update p to advance to the new end to the list before appending our new record.
- // Note that for AutoTunnel this should never happen, but this check makes the code future-proof.
- while (*p) p=&(*p)->next;
- *p = rr;
- if (rr->resrec.RecordType == kDNSRecordTypeUnique) rr->resrec.RecordType = kDNSRecordTypeVerified;
- rr->ProbeCount = 0;
- rr->AnnounceCount = 0;
- if (rr->state != regState_NoTarget) ActivateUnicastRegistration(m, rr);
- return(mStatus_NoError); // <--- Note: For unicast records, code currently bails out at this point
- }
+ if (AuthRecord_uDNS(rr))
+ {
+ if (!m->NewLocalRecords) m->NewLocalRecords = rr;
+ // When we called SetTargetToHostName, it may have caused mDNS_Register_internal to be re-entered, appending new
+ // records to the list, so we now need to update p to advance to the new end to the list before appending our new record.
+ // Note that for AutoTunnel this should never happen, but this check makes the code future-proof.
+ while (*p) p=&(*p)->next;
+ *p = rr;
+ if (rr->resrec.RecordType == kDNSRecordTypeUnique) rr->resrec.RecordType = kDNSRecordTypeVerified;
+ rr->ProbeCount = 0;
+ rr->ProbeRestartCount = 0;
+ rr->AnnounceCount = 0;
+ if (rr->state != regState_NoTarget) ActivateUnicastRegistration(m, rr);
+ return(mStatus_NoError); // <--- Note: For unicast records, code currently bails out at this point
+ }
#endif
- // Now that we've finished building our new record, make sure it's not identical to one we already have
- if (RRLocalOnly(rr))
- {
- rr->ProbeCount = 0;
- rr->AnnounceCount = 0;
- r = CheckAuthIdenticalRecord(&m->rrauth, rr);
- }
- else
- {
- for (r = m->ResourceRecords; r; r=r->next)
- if (RecordIsLocalDuplicate(r, rr))
- {
- if (r->resrec.RecordType == kDNSRecordTypeDeregistering) r->AnnounceCount = 0;
- else break;
- }
- }
-
- if (r)
- {
- debugf("mDNS_Register_internal:Adding to duplicate list %s", ARDisplayString(m,rr));
- *d = rr;
- // If the previous copy of this record is already verified unique,
- // then indicate that we should move this record promptly to kDNSRecordTypeUnique state.
- // Setting ProbeCount to zero will cause SendQueries() to advance this record to
- // kDNSRecordTypeVerified state and call the client callback at the next appropriate time.
- if (rr->resrec.RecordType == kDNSRecordTypeUnique && r->resrec.RecordType == kDNSRecordTypeVerified)
- rr->ProbeCount = 0;
- }
- else
- {
- debugf("mDNS_Register_internal: Adding to active record list %s", ARDisplayString(m,rr));
- if (RRLocalOnly(rr))
- {
- AuthGroup *ag;
- ag = InsertAuthRecord(m, &m->rrauth, rr);
- if (ag && !ag->NewLocalOnlyRecords) {
- m->NewLocalOnlyRecords = mDNStrue;
- ag->NewLocalOnlyRecords = rr;
- }
- // No probing for LocalOnly records, Acknowledge them right away
- if (rr->resrec.RecordType == kDNSRecordTypeUnique) rr->resrec.RecordType = kDNSRecordTypeVerified;
- AcknowledgeRecord(m, rr);
- return(mStatus_NoError);
- }
- else
- {
- if (!m->NewLocalRecords) m->NewLocalRecords = rr;
- *p = rr;
- }
- }
-
- if (!AuthRecord_uDNS(rr)) // This check is superfluous, given that for unicast records we (currently) bail out above
- {
- // For records that are not going to probe, acknowledge them right away
- if (rr->resrec.RecordType != kDNSRecordTypeUnique && rr->resrec.RecordType != kDNSRecordTypeDeregistering)
- AcknowledgeRecord(m, rr);
-
- // Adding a record may affect whether or not we should sleep
- mDNS_UpdateAllowSleep(m);
- }
-
- return(mStatus_NoError);
- }
+ // Now that we've finished building our new record, make sure it's not identical to one we already have
+ if (RRLocalOnly(rr))
+ {
+ rr->ProbeCount = 0;
+ rr->ProbeRestartCount = 0;
+ rr->AnnounceCount = 0;
+ r = CheckAuthIdenticalRecord(&m->rrauth, rr);
+ }
+ else
+ {
+ for (r = m->ResourceRecords; r; r=r->next)
+ if (RecordIsLocalDuplicate(r, rr))
+ {
+ if (r->resrec.RecordType == kDNSRecordTypeDeregistering) r->AnnounceCount = 0;
+ else break;
+ }
+ }
+
+ if (r)
+ {
+ debugf("mDNS_Register_internal:Adding to duplicate list %s", ARDisplayString(m,rr));
+ *d = rr;
+ // If the previous copy of this record is already verified unique,
+ // then indicate that we should move this record promptly to kDNSRecordTypeUnique state.
+ // Setting ProbeCount to zero will cause SendQueries() to advance this record to
+ // kDNSRecordTypeVerified state and call the client callback at the next appropriate time.
+ if (rr->resrec.RecordType == kDNSRecordTypeUnique && r->resrec.RecordType == kDNSRecordTypeVerified)
+ rr->ProbeCount = 0;
+ }
+ else
+ {
+ debugf("mDNS_Register_internal: Adding to active record list %s", ARDisplayString(m,rr));
+ if (RRLocalOnly(rr))
+ {
+ AuthGroup *ag;
+ ag = InsertAuthRecord(m, &m->rrauth, rr);
+ if (ag && !ag->NewLocalOnlyRecords) {
+ m->NewLocalOnlyRecords = mDNStrue;
+ ag->NewLocalOnlyRecords = rr;
+ }
+ // No probing for LocalOnly records, Acknowledge them right away
+ if (rr->resrec.RecordType == kDNSRecordTypeUnique) rr->resrec.RecordType = kDNSRecordTypeVerified;
+ AcknowledgeRecord(m, rr);
+ return(mStatus_NoError);
+ }
+ else
+ {
+ if (!m->NewLocalRecords) m->NewLocalRecords = rr;
+ *p = rr;
+ }
+ }
+
+ // If this is a keepalive record, fetch the MAC address of the remote host.
+ // This is used by the in-NIC proxy to send the keepalive packets.
+ if (mDNS_KeepaliveRecord(&rr->resrec))
+ {
+ // Set the record type to known unique to prevent probing keep alive records.
+ // Also make sure we do not announce the keepalive records.
+ rr->resrec.RecordType = kDNSRecordTypeKnownUnique;
+ rr->AnnounceCount = 0;
+ mDNSAddr raddr;
+ getKeepaliveRaddr(m, rr, &raddr);
+ // This is an asynchronous call. Once the remote MAC address is available, helper will schedule an
+ // asynchronous task to update the resource record
+ mDNSPlatformGetRemoteMacAddr(m, &raddr);
+ }
+
+ if (!AuthRecord_uDNS(rr)) // This check is superfluous, given that for unicast records we (currently) bail out above
+ {
+ // We have inserted the record in the list. See if we have to advertise the A/AAAA,HINFO,PTR records.
+ IncrementAutoTargetServices(m, rr);
+ // For records that are not going to probe, acknowledge them right away
+ if (rr->resrec.RecordType != kDNSRecordTypeUnique && rr->resrec.RecordType != kDNSRecordTypeDeregistering)
+ AcknowledgeRecord(m, rr);
+
+ // Adding a record may affect whether or not we should sleep
+ mDNS_UpdateAllowSleep(m);
+ }
+
+ return(mStatus_NoError);
+}
mDNSlocal void RecordProbeFailure(mDNS *const m, const AuthRecord *const rr)
- {
- m->ProbeFailTime = m->timenow;
- m->NumFailedProbes++;
- // If we've had fifteen or more probe failures, rate-limit to one every five seconds.
- // If a bunch of hosts have all been configured with the same name, then they'll all
- // conflict and run through the same series of names: name-2, name-3, name-4, etc.,
- // up to name-10. After that they'll start adding random increments in the range 1-100,
- // so they're more likely to branch out in the available namespace and settle on a set of
- // unique names quickly. If after five more tries the host is still conflicting, then we
- // may have a serious problem, so we start rate-limiting so we don't melt down the network.
- if (m->NumFailedProbes >= 15)
- {
- m->SuppressProbes = NonZeroTime(m->timenow + mDNSPlatformOneSecond * 5);
- LogMsg("Excessive name conflicts (%lu) for %##s (%s); rate limiting in effect",
- m->NumFailedProbes, rr->resrec.name->c, DNSTypeName(rr->resrec.rrtype));
- }
- }
+{
+ m->ProbeFailTime = m->timenow;
+ m->NumFailedProbes++;
+ // If we've had fifteen or more probe failures, rate-limit to one every five seconds.
+ // If a bunch of hosts have all been configured with the same name, then they'll all
+ // conflict and run through the same series of names: name-2, name-3, name-4, etc.,
+ // up to name-10. After that they'll start adding random increments in the range 1-100,
+ // so they're more likely to branch out in the available namespace and settle on a set of
+ // unique names quickly. If after five more tries the host is still conflicting, then we
+ // may have a serious problem, so we start rate-limiting so we don't melt down the network.
+ if (m->NumFailedProbes >= 15)
+ {
+ m->SuppressProbes = NonZeroTime(m->timenow + mDNSPlatformOneSecond * 5);
+ LogMsg("Excessive name conflicts (%lu) for %##s (%s); rate limiting in effect",
+ m->NumFailedProbes, rr->resrec.name->c, DNSTypeName(rr->resrec.rrtype));
+ }
+}
mDNSlocal void CompleteRDataUpdate(mDNS *const m, AuthRecord *const rr)
- {
- RData *OldRData = rr->resrec.rdata;
- mDNSu16 OldRDLen = rr->resrec.rdlength;
- SetNewRData(&rr->resrec, rr->NewRData, rr->newrdlength); // Update our rdata
- rr->NewRData = mDNSNULL; // Clear the NewRData pointer ...
- if (rr->UpdateCallback)
- rr->UpdateCallback(m, rr, OldRData, OldRDLen); // ... and let the client know
- }
+{
+ RData *OldRData = rr->resrec.rdata;
+ mDNSu16 OldRDLen = rr->resrec.rdlength;
+ SetNewRData(&rr->resrec, rr->NewRData, rr->newrdlength); // Update our rdata
+ rr->NewRData = mDNSNULL; // Clear the NewRData pointer ...
+ if (rr->UpdateCallback)
+ rr->UpdateCallback(m, rr, OldRData, OldRDLen); // ... and let the client know
+}
// Note: mDNS_Deregister_internal can call a user callback, which may change the record list and/or question list.
// Any code walking either list must use the CurrentQuestion and/or CurrentRecord mechanism to protect against this.
// Exported so uDNS.c can call this
mDNSexport mStatus mDNS_Deregister_internal(mDNS *const m, AuthRecord *const rr, mDNS_Dereg_type drt)
- {
- AuthRecord *r2;
- mDNSu8 RecordType = rr->resrec.RecordType;
- AuthRecord **p = &m->ResourceRecords; // Find this record in our list of active records
- mDNSBool dupList = mDNSfalse;
-
- if (RRLocalOnly(rr))
- {
- AuthGroup *a;
- AuthGroup **ag = &a;
- AuthRecord **rp;
- const mDNSu32 slot = AuthHashSlot(rr->resrec.name);
-
- a = AuthGroupForRecord(&m->rrauth, slot, &rr->resrec);
- if (!a) return mDNSfalse;
- rp = &(*ag)->members;
- while (*rp && *rp != rr) rp=&(*rp)->next;
- p = rp;
- }
- else
- {
- while (*p && *p != rr) p=&(*p)->next;
- }
-
- if (*p)
- {
- // We found our record on the main list. See if there are any duplicates that need special handling.
- if (drt == mDNS_Dereg_conflict) // If this was a conflict, see that all duplicates get the same treatment
- {
- // Scan for duplicates of rr, and mark them for deregistration at the end of this routine, after we've finished
- // deregistering rr. We need to do this scan *before* we give the client the chance to free and reuse the rr memory.
- for (r2 = m->DuplicateRecords; r2; r2=r2->next) if (RecordIsLocalDuplicate(r2, rr)) r2->ProbeCount = 0xFF;
- }
- else
- {
- // Before we delete the record (and potentially send a goodbye packet)
- // first see if we have a record on the duplicate list ready to take over from it.
- AuthRecord **d = &m->DuplicateRecords;
- while (*d && !RecordIsLocalDuplicate(*d, rr)) d=&(*d)->next;
- if (*d)
- {
- AuthRecord *dup = *d;
- debugf("mDNS_Register_internal: Duplicate record %p taking over from %p %##s (%s)",
- dup, rr, rr->resrec.name->c, DNSTypeName(rr->resrec.rrtype));
- *d = dup->next; // Cut replacement record from DuplicateRecords list
- if (RRLocalOnly(rr))
- {
- dup->next = mDNSNULL;
- if (!InsertAuthRecord(m, &m->rrauth, dup)) LogMsg("mDNS_Deregister_internal: ERROR!! cannot insert %s", ARDisplayString(m, dup));
- }
- else
- {
- dup->next = rr->next; // And then...
- rr->next = dup; // ... splice it in right after the record we're about to delete
- }
- dup->resrec.RecordType = rr->resrec.RecordType;
- dup->ProbeCount = rr->ProbeCount;
- dup->AnnounceCount = rr->AnnounceCount;
- dup->RequireGoodbye = rr->RequireGoodbye;
- dup->AnsweredLocalQ = rr->AnsweredLocalQ;
- dup->ImmedAnswer = rr->ImmedAnswer;
- dup->ImmedUnicast = rr->ImmedUnicast;
- dup->ImmedAdditional = rr->ImmedAdditional;
- dup->v4Requester = rr->v4Requester;
- dup->v6Requester = rr->v6Requester;
- dup->ThisAPInterval = rr->ThisAPInterval;
- dup->LastAPTime = rr->LastAPTime;
- dup->LastMCTime = rr->LastMCTime;
- dup->LastMCInterface = rr->LastMCInterface;
- dup->Private = rr->Private;
- dup->state = rr->state;
- rr->RequireGoodbye = mDNSfalse;
- rr->AnsweredLocalQ = mDNSfalse;
- }
- }
- }
- else
- {
- // We didn't find our record on the main list; try the DuplicateRecords list instead.
- p = &m->DuplicateRecords;
- while (*p && *p != rr) p=&(*p)->next;
- // If we found our record on the duplicate list, then make sure we don't send a goodbye for it
- if (*p) { rr->RequireGoodbye = mDNSfalse; dupList = mDNStrue; }
- if (*p) debugf("mDNS_Deregister_internal: Deleting DuplicateRecord %p %##s (%s)",
- rr, rr->resrec.name->c, DNSTypeName(rr->resrec.rrtype));
- }
-
- if (!*p)
- {
- // No need to log an error message if we already know this is a potentially repeated deregistration
- if (drt != mDNS_Dereg_repeat)
- LogMsg("mDNS_Deregister_internal: Record %p not found in list %s", rr, ARDisplayString(m,rr));
- return(mStatus_BadReferenceErr);
- }
-
- // If this is a shared record and we've announced it at least once,
- // we need to retract that announcement before we delete the record
-
- // If this is a record (including mDNSInterface_LocalOnly records) for which we've given local-only answers then
- // it's tempting to just do "AnswerAllLocalQuestionsWithLocalAuthRecord(m, rr, mDNSfalse)" here, but that would not not be safe.
- // The AnswerAllLocalQuestionsWithLocalAuthRecord routine walks the question list invoking client callbacks, using the "m->CurrentQuestion"
- // mechanism to cope with the client callback modifying the question list while that's happening.
- // However, mDNS_Deregister could have been called from a client callback (e.g. from the domain enumeration callback FoundDomain)
- // which means that the "m->CurrentQuestion" mechanism is already in use to protect that list, so we can't use it twice.
- // More generally, if we invoke callbacks from within a client callback, then those callbacks could deregister other
- // records, thereby invoking yet more callbacks, without limit.
- // The solution is to defer delivering the "Remove" events until mDNS_Execute time, just like we do for sending
- // actual goodbye packets.
-
+{
+ AuthRecord *r2;
+ mDNSu8 RecordType = rr->resrec.RecordType;
+ AuthRecord **p = &m->ResourceRecords; // Find this record in our list of active records
+ mDNSBool dupList = mDNSfalse;
+
+ if (RRLocalOnly(rr))
+ {
+ AuthGroup *a;
+ AuthGroup **ag = &a;
+ AuthRecord **rp;
+ const mDNSu32 slot = AuthHashSlot(rr->resrec.name);
+
+ a = AuthGroupForRecord(&m->rrauth, slot, &rr->resrec);
+ if (!a) return mDNSfalse;
+ rp = &(*ag)->members;
+ while (*rp && *rp != rr) rp=&(*rp)->next;
+ p = rp;
+ }
+ else
+ {
+ while (*p && *p != rr) p=&(*p)->next;
+ }
+
+ if (*p)
+ {
+ // We found our record on the main list. See if there are any duplicates that need special handling.
+ if (drt == mDNS_Dereg_conflict) // If this was a conflict, see that all duplicates get the same treatment
+ {
+ // Scan for duplicates of rr, and mark them for deregistration at the end of this routine, after we've finished
+ // deregistering rr. We need to do this scan *before* we give the client the chance to free and reuse the rr memory.
+ for (r2 = m->DuplicateRecords; r2; r2=r2->next) if (RecordIsLocalDuplicate(r2, rr)) r2->ProbeCount = 0xFF;
+ }
+ else
+ {
+ // Before we delete the record (and potentially send a goodbye packet)
+ // first see if we have a record on the duplicate list ready to take over from it.
+ AuthRecord **d = &m->DuplicateRecords;
+ while (*d && !RecordIsLocalDuplicate(*d, rr)) d=&(*d)->next;
+ if (*d)
+ {
+ AuthRecord *dup = *d;
+ debugf("mDNS_Register_internal: Duplicate record %p taking over from %p %##s (%s)",
+ dup, rr, rr->resrec.name->c, DNSTypeName(rr->resrec.rrtype));
+ *d = dup->next; // Cut replacement record from DuplicateRecords list
+ if (RRLocalOnly(rr))
+ {
+ dup->next = mDNSNULL;
+ if (!InsertAuthRecord(m, &m->rrauth, dup)) LogMsg("mDNS_Deregister_internal: ERROR!! cannot insert %s", ARDisplayString(m, dup));
+ }
+ else
+ {
+ dup->next = rr->next; // And then...
+ rr->next = dup; // ... splice it in right after the record we're about to delete
+ }
+ dup->resrec.RecordType = rr->resrec.RecordType;
+ dup->ProbeCount = rr->ProbeCount;
+ dup->ProbeRestartCount = rr->ProbeRestartCount;
+ dup->AnnounceCount = rr->AnnounceCount;
+ dup->RequireGoodbye = rr->RequireGoodbye;
+ dup->AnsweredLocalQ = rr->AnsweredLocalQ;
+ dup->ImmedAnswer = rr->ImmedAnswer;
+ dup->ImmedUnicast = rr->ImmedUnicast;
+ dup->ImmedAdditional = rr->ImmedAdditional;
+ dup->v4Requester = rr->v4Requester;
+ dup->v6Requester = rr->v6Requester;
+ dup->ThisAPInterval = rr->ThisAPInterval;
+ dup->LastAPTime = rr->LastAPTime;
+ dup->LastMCTime = rr->LastMCTime;
+ dup->LastMCInterface = rr->LastMCInterface;
+ dup->Private = rr->Private;
+ dup->state = rr->state;
+ rr->RequireGoodbye = mDNSfalse;
+ rr->AnsweredLocalQ = mDNSfalse;
+ }
+ }
+ }
+ else
+ {
+ // We didn't find our record on the main list; try the DuplicateRecords list instead.
+ p = &m->DuplicateRecords;
+ while (*p && *p != rr) p=&(*p)->next;
+ // If we found our record on the duplicate list, then make sure we don't send a goodbye for it
+ if (*p)
+ {
+ // Duplicate records are not used for sending wakeups or goodbyes. Hence, deregister them
+ // immediately. When there is a conflict, we deregister all the conflicting duplicate records
+ // also that have been marked above in this function. In that case, we come here and if we don't
+ // deregister (unilink from the DuplicateRecords list), we will be recursing infinitely. Hence,
+ // clear the HMAC which will cause it to deregister. See <rdar://problem/10380988> for
+ // details.
+ rr->WakeUp.HMAC = zeroEthAddr;
+ rr->RequireGoodbye = mDNSfalse;
+ rr->resrec.RecordType = kDNSRecordTypeDeregistering;
+ dupList = mDNStrue;
+ }
+ if (*p) debugf("mDNS_Deregister_internal: Deleting DuplicateRecord %p %##s (%s)",
+ rr, rr->resrec.name->c, DNSTypeName(rr->resrec.rrtype));
+ }
+
+ if (!*p)
+ {
+ // No need to log an error message if we already know this is a potentially repeated deregistration
+ if (drt != mDNS_Dereg_repeat)
+ LogMsg("mDNS_Deregister_internal: Record %p not found in list %s", rr, ARDisplayString(m,rr));
+ return(mStatus_BadReferenceErr);
+ }
+
+ // If this is a shared record and we've announced it at least once,
+ // we need to retract that announcement before we delete the record
+
+ // If this is a record (including mDNSInterface_LocalOnly records) for which we've given local-only answers then
+ // it's tempting to just do "AnswerAllLocalQuestionsWithLocalAuthRecord(m, rr, mDNSfalse)" here, but that would not not be safe.
+ // The AnswerAllLocalQuestionsWithLocalAuthRecord routine walks the question list invoking client callbacks, using the "m->CurrentQuestion"
+ // mechanism to cope with the client callback modifying the question list while that's happening.
+ // However, mDNS_Deregister could have been called from a client callback (e.g. from the domain enumeration callback FoundDomain)
+ // which means that the "m->CurrentQuestion" mechanism is already in use to protect that list, so we can't use it twice.
+ // More generally, if we invoke callbacks from within a client callback, then those callbacks could deregister other
+ // records, thereby invoking yet more callbacks, without limit.
+ // The solution is to defer delivering the "Remove" events until mDNS_Execute time, just like we do for sending
+ // actual goodbye packets.
+
#ifndef UNICAST_DISABLED
- if (AuthRecord_uDNS(rr))
- {
- if (rr->RequireGoodbye)
- {
- if (rr->tcp) { DisposeTCPConn(rr->tcp); rr->tcp = mDNSNULL; }
- rr->resrec.RecordType = kDNSRecordTypeDeregistering;
- m->LocalRemoveEvents = mDNStrue;
- uDNS_DeregisterRecord(m, rr);
- // At this point unconditionally we bail out
- // Either uDNS_DeregisterRecord will have completed synchronously, and called CompleteDeregistration,
- // which calls us back here with RequireGoodbye set to false, or it will have initiated the deregistration
- // process and will complete asynchronously. Either way we don't need to do anything more here.
- return(mStatus_NoError);
- }
- // Sometimes the records don't complete proper deregistration i.e., don't wait for a response
- // from the server. In that case, if the records have been part of a group update, clear the
- // state here. Some recors e.g., AutoTunnel gets reused without ever being completely initialized
- rr->updateid = zeroID;
-
- // We defer cleaning up NAT state only after sending goodbyes. This is important because
- // RecordRegistrationGotZoneData guards against creating NAT state if clientContext is non-NULL.
- // This happens today when we turn on/off interface where we get multiple network transitions
- // and RestartRecordGetZoneData triggers re-registration of the resource records even though
- // they may be in Registered state which causes NAT information to be setup multiple times. Defering
- // the cleanup here keeps clientContext non-NULL and hence prevents that. Note that cleaning up
- // NAT state here takes care of the case where we did not send goodbyes at all.
- if (rr->NATinfo.clientContext)
- {
- mDNS_StopNATOperation_internal(m, &rr->NATinfo);
- rr->NATinfo.clientContext = mDNSNULL;
- }
- if (rr->nta) { CancelGetZoneData(m, rr->nta); rr->nta = mDNSNULL; }
- if (rr->tcp) { DisposeTCPConn(rr->tcp); rr->tcp = mDNSNULL; }
- }
+ if (AuthRecord_uDNS(rr))
+ {
+ if (rr->RequireGoodbye)
+ {
+ if (rr->tcp) { DisposeTCPConn(rr->tcp); rr->tcp = mDNSNULL; }
+ rr->resrec.RecordType = kDNSRecordTypeDeregistering;
+ m->LocalRemoveEvents = mDNStrue;
+ uDNS_DeregisterRecord(m, rr);
+ // At this point unconditionally we bail out
+ // Either uDNS_DeregisterRecord will have completed synchronously, and called CompleteDeregistration,
+ // which calls us back here with RequireGoodbye set to false, or it will have initiated the deregistration
+ // process and will complete asynchronously. Either way we don't need to do anything more here.
+ return(mStatus_NoError);
+ }
+ // Sometimes the records don't complete proper deregistration i.e., don't wait for a response
+ // from the server. In that case, if the records have been part of a group update, clear the
+ // state here. Some recors e.g., AutoTunnel gets reused without ever being completely initialized
+ rr->updateid = zeroID;
+
+ // We defer cleaning up NAT state only after sending goodbyes. This is important because
+ // RecordRegistrationGotZoneData guards against creating NAT state if clientContext is non-NULL.
+ // This happens today when we turn on/off interface where we get multiple network transitions
+ // and RestartRecordGetZoneData triggers re-registration of the resource records even though
+ // they may be in Registered state which causes NAT information to be setup multiple times. Defering
+ // the cleanup here keeps clientContext non-NULL and hence prevents that. Note that cleaning up
+ // NAT state here takes care of the case where we did not send goodbyes at all.
+ if (rr->NATinfo.clientContext)
+ {
+ mDNS_StopNATOperation_internal(m, &rr->NATinfo);
+ rr->NATinfo.clientContext = mDNSNULL;
+ }
+ if (rr->nta) { CancelGetZoneData(m, rr->nta); rr->nta = mDNSNULL; }
+ if (rr->tcp) { DisposeTCPConn(rr->tcp); rr->tcp = mDNSNULL; }
+ }
#endif // UNICAST_DISABLED
- if (RecordType == kDNSRecordTypeUnregistered)
- LogMsg("mDNS_Deregister_internal: %s already marked kDNSRecordTypeUnregistered", ARDisplayString(m, rr));
- else if (RecordType == kDNSRecordTypeDeregistering)
- {
- LogMsg("mDNS_Deregister_internal: %s already marked kDNSRecordTypeDeregistering", ARDisplayString(m, rr));
- return(mStatus_BadReferenceErr);
- }
-
- // <rdar://problem/7457925> Local-only questions don't get remove events for unique records
- // We may want to consider changing this code so that we generate local-only question "rmv"
- // events (and maybe goodbye packets too) for unique records as well as for shared records
- // Note: If we change the logic for this "if" statement, need to ensure that the code in
- // CompleteDeregistration() sets the appropriate state variables to gaurantee that "else"
- // clause will execute here and the record will be cut from the list.
- if (rr->WakeUp.HMAC.l[0] ||
- (RecordType == kDNSRecordTypeShared && (rr->RequireGoodbye || rr->AnsweredLocalQ)))
- {
- verbosedebugf("mDNS_Deregister_internal: Starting deregistration for %s", ARDisplayString(m, rr));
- rr->resrec.RecordType = kDNSRecordTypeDeregistering;
- rr->resrec.rroriginalttl = 0;
- rr->AnnounceCount = rr->WakeUp.HMAC.l[0] ? WakeupCount : (drt == mDNS_Dereg_rapid) ? 1 : GoodbyeCount;
- rr->ThisAPInterval = mDNSPlatformOneSecond * 2;
- rr->LastAPTime = m->timenow - rr->ThisAPInterval;
- m->LocalRemoveEvents = mDNStrue;
- if (m->NextScheduledResponse - (m->timenow + mDNSPlatformOneSecond/10) >= 0)
- m->NextScheduledResponse = (m->timenow + mDNSPlatformOneSecond/10);
- }
- else
- {
- if (!dupList && RRLocalOnly(rr))
- {
- AuthGroup *ag = RemoveAuthRecord(m, &m->rrauth, rr);
- if (ag->NewLocalOnlyRecords == rr) ag->NewLocalOnlyRecords = rr->next;
- }
- else
- {
- *p = rr->next; // Cut this record from the list
- if (m->NewLocalRecords == rr) m->NewLocalRecords = rr->next;
- }
- // If someone is about to look at this, bump the pointer forward
- if (m->CurrentRecord == rr) m->CurrentRecord = rr->next;
- rr->next = mDNSNULL;
-
- // Should we generate local remove events here?
- // i.e. something like:
- // if (rr->AnsweredLocalQ) { AnswerAllLocalQuestionsWithLocalAuthRecord(m, rr, mDNSfalse); rr->AnsweredLocalQ = mDNSfalse; }
-
- verbosedebugf("mDNS_Deregister_internal: Deleting record for %s", ARDisplayString(m, rr));
- rr->resrec.RecordType = kDNSRecordTypeUnregistered;
-
- if ((drt == mDNS_Dereg_conflict || drt == mDNS_Dereg_repeat) && RecordType == kDNSRecordTypeShared)
- debugf("mDNS_Deregister_internal: Cannot have a conflict on a shared record! %##s (%s)",
- rr->resrec.name->c, DNSTypeName(rr->resrec.rrtype));
-
- // If we have an update queued up which never executed, give the client a chance to free that memory
- if (rr->NewRData) CompleteRDataUpdate(m, rr); // Update our rdata, clear the NewRData pointer, and return memory to the client
-
-
- // CAUTION: MUST NOT do anything more with rr after calling rr->Callback(), because the client's callback function
- // is allowed to do anything, including starting/stopping queries, registering/deregistering records, etc.
- // In this case the likely client action to the mStatus_MemFree message is to free the memory,
- // so any attempt to touch rr after this is likely to lead to a crash.
- if (drt != mDNS_Dereg_conflict)
- {
- mDNS_DropLockBeforeCallback(); // Allow client to legally make mDNS API calls from the callback
- LogInfo("mDNS_Deregister_internal: mStatus_MemFree for %s", ARDisplayString(m, rr));
- if (rr->RecordCallback)
- rr->RecordCallback(m, rr, mStatus_MemFree); // MUST NOT touch rr after this
- mDNS_ReclaimLockAfterCallback(); // Decrement mDNS_reentrancy to block mDNS API calls again
- }
- else
- {
- RecordProbeFailure(m, rr);
- mDNS_DropLockBeforeCallback(); // Allow client to legally make mDNS API calls from the callback
- if (rr->RecordCallback)
- rr->RecordCallback(m, rr, mStatus_NameConflict); // MUST NOT touch rr after this
- mDNS_ReclaimLockAfterCallback(); // Decrement mDNS_reentrancy to block mDNS API calls again
- // Now that we've finished deregistering rr, check our DuplicateRecords list for any that we marked previously.
- // Note that with all the client callbacks going on, by the time we get here all the
- // records we marked may have been explicitly deregistered by the client anyway.
- r2 = m->DuplicateRecords;
- while (r2)
- {
- if (r2->ProbeCount != 0xFF) r2 = r2->next;
- else { mDNS_Deregister_internal(m, r2, mDNS_Dereg_conflict); r2 = m->DuplicateRecords; }
- }
- }
- }
- mDNS_UpdateAllowSleep(m);
- return(mStatus_NoError);
- }
+ if (RecordType == kDNSRecordTypeUnregistered)
+ LogMsg("mDNS_Deregister_internal: %s already marked kDNSRecordTypeUnregistered", ARDisplayString(m, rr));
+ else if (RecordType == kDNSRecordTypeDeregistering)
+ {
+ LogMsg("mDNS_Deregister_internal: %s already marked kDNSRecordTypeDeregistering", ARDisplayString(m, rr));
+ return(mStatus_BadReferenceErr);
+ }
+
+ // <rdar://problem/7457925> Local-only questions don't get remove events for unique records
+ // We may want to consider changing this code so that we generate local-only question "rmv"
+ // events (and maybe goodbye packets too) for unique records as well as for shared records
+ // Note: If we change the logic for this "if" statement, need to ensure that the code in
+ // CompleteDeregistration() sets the appropriate state variables to gaurantee that "else"
+ // clause will execute here and the record will be cut from the list.
+ if (rr->WakeUp.HMAC.l[0] ||
+ (RecordType == kDNSRecordTypeShared && (rr->RequireGoodbye || rr->AnsweredLocalQ)))
+ {
+ verbosedebugf("mDNS_Deregister_internal: Starting deregistration for %s", ARDisplayString(m, rr));
+ rr->resrec.RecordType = kDNSRecordTypeDeregistering;
+ rr->resrec.rroriginalttl = 0;
+ rr->AnnounceCount = rr->WakeUp.HMAC.l[0] ? WakeupCount : (drt == mDNS_Dereg_rapid) ? 1 : GoodbyeCount;
+ rr->ThisAPInterval = mDNSPlatformOneSecond * 2;
+ rr->LastAPTime = m->timenow - rr->ThisAPInterval;
+ m->LocalRemoveEvents = mDNStrue;
+ if (m->NextScheduledResponse - (m->timenow + mDNSPlatformOneSecond/10) >= 0)
+ m->NextScheduledResponse = (m->timenow + mDNSPlatformOneSecond/10);
+ }
+ else
+ {
+ if (!dupList && RRLocalOnly(rr))
+ {
+ AuthGroup *ag = RemoveAuthRecord(m, &m->rrauth, rr);
+ if (ag->NewLocalOnlyRecords == rr) ag->NewLocalOnlyRecords = rr->next;
+ }
+ else
+ {
+ *p = rr->next; // Cut this record from the list
+ if (m->NewLocalRecords == rr) m->NewLocalRecords = rr->next;
+ DecrementAutoTargetServices(m, rr);
+ }
+ // If someone is about to look at this, bump the pointer forward
+ if (m->CurrentRecord == rr) m->CurrentRecord = rr->next;
+ rr->next = mDNSNULL;
+
+ // Should we generate local remove events here?
+ // i.e. something like:
+ // if (rr->AnsweredLocalQ) { AnswerAllLocalQuestionsWithLocalAuthRecord(m, rr, mDNSfalse); rr->AnsweredLocalQ = mDNSfalse; }
+
+ verbosedebugf("mDNS_Deregister_internal: Deleting record for %s", ARDisplayString(m, rr));
+ rr->resrec.RecordType = kDNSRecordTypeUnregistered;
+
+ if ((drt == mDNS_Dereg_conflict || drt == mDNS_Dereg_repeat) && RecordType == kDNSRecordTypeShared)
+ debugf("mDNS_Deregister_internal: Cannot have a conflict on a shared record! %##s (%s)",
+ rr->resrec.name->c, DNSTypeName(rr->resrec.rrtype));
+
+ // If we have an update queued up which never executed, give the client a chance to free that memory
+ if (rr->NewRData) CompleteRDataUpdate(m, rr); // Update our rdata, clear the NewRData pointer, and return memory to the client
+
+
+ // CAUTION: MUST NOT do anything more with rr after calling rr->Callback(), because the client's callback function
+ // is allowed to do anything, including starting/stopping queries, registering/deregistering records, etc.
+ // In this case the likely client action to the mStatus_MemFree message is to free the memory,
+ // so any attempt to touch rr after this is likely to lead to a crash.
+ if (drt != mDNS_Dereg_conflict)
+ {
+ mDNS_DropLockBeforeCallback(); // Allow client to legally make mDNS API calls from the callback
+ LogInfo("mDNS_Deregister_internal: mStatus_MemFree for %s", ARDisplayString(m, rr));
+ if (rr->RecordCallback)
+ rr->RecordCallback(m, rr, mStatus_MemFree); // MUST NOT touch rr after this
+ mDNS_ReclaimLockAfterCallback(); // Decrement mDNS_reentrancy to block mDNS API calls again
+ }
+ else
+ {
+ RecordProbeFailure(m, rr);
+ mDNS_DropLockBeforeCallback(); // Allow client to legally make mDNS API calls from the callback
+ if (rr->RecordCallback)
+ rr->RecordCallback(m, rr, mStatus_NameConflict); // MUST NOT touch rr after this
+ mDNS_ReclaimLockAfterCallback(); // Decrement mDNS_reentrancy to block mDNS API calls again
+ // Now that we've finished deregistering rr, check our DuplicateRecords list for any that we marked previously.
+ // Note that with all the client callbacks going on, by the time we get here all the
+ // records we marked may have been explicitly deregistered by the client anyway.
+ r2 = m->DuplicateRecords;
+ while (r2)
+ {
+ if (r2->ProbeCount != 0xFF)
+ {
+ r2 = r2->next;
+ }
+ else
+ {
+ mDNS_Deregister_internal(m, r2, mDNS_Dereg_conflict);
+ // As this is a duplicate record, it will be unlinked from the list
+ // immediately
+ r2 = m->DuplicateRecords;
+ }
+ }
+ }
+ }
+ mDNS_UpdateAllowSleep(m);
+ return(mStatus_NoError);
+}
// ***************************************************************************
#if COMPILER_LIKES_PRAGMA_MARK
#endif
mDNSlocal void AddRecordToResponseList(AuthRecord ***nrpp, AuthRecord *rr, AuthRecord *add)
- {
- if (rr->NextResponse == mDNSNULL && *nrpp != &rr->NextResponse)
- {
- **nrpp = rr;
- // NR_AdditionalTo must point to a record with NR_AnswerTo set (and not NR_AdditionalTo)
- // If 'add' does not meet this requirement, then follow its NR_AdditionalTo pointer to a record that does
- // The referenced record will definitely be acceptable (by recursive application of this rule)
- if (add && add->NR_AdditionalTo) add = add->NR_AdditionalTo;
- rr->NR_AdditionalTo = add;
- *nrpp = &rr->NextResponse;
- }
- debugf("AddRecordToResponseList: %##s (%s) already in list", rr->resrec.name->c, DNSTypeName(rr->resrec.rrtype));
- }
+{
+ if (rr->NextResponse == mDNSNULL && *nrpp != &rr->NextResponse)
+ {
+ **nrpp = rr;
+ // NR_AdditionalTo must point to a record with NR_AnswerTo set (and not NR_AdditionalTo)
+ // If 'add' does not meet this requirement, then follow its NR_AdditionalTo pointer to a record that does
+ // The referenced record will definitely be acceptable (by recursive application of this rule)
+ if (add && add->NR_AdditionalTo) add = add->NR_AdditionalTo;
+ rr->NR_AdditionalTo = add;
+ *nrpp = &rr->NextResponse;
+ }
+ debugf("AddRecordToResponseList: %##s (%s) already in list", rr->resrec.name->c, DNSTypeName(rr->resrec.rrtype));
+}
mDNSlocal void AddAdditionalsToResponseList(mDNS *const m, AuthRecord *ResponseRecords, AuthRecord ***nrpp, const mDNSInterfaceID InterfaceID)
- {
- AuthRecord *rr, *rr2;
- for (rr=ResponseRecords; rr; rr=rr->NextResponse) // For each record we plan to put
- {
- // (Note: This is an "if", not a "while". If we add a record, we'll find it again
- // later in the "for" loop, and we will follow further "additional" links then.)
- if (rr->Additional1 && ResourceRecordIsValidInterfaceAnswer(rr->Additional1, InterfaceID))
- AddRecordToResponseList(nrpp, rr->Additional1, rr);
-
- if (rr->Additional2 && ResourceRecordIsValidInterfaceAnswer(rr->Additional2, InterfaceID))
- AddRecordToResponseList(nrpp, rr->Additional2, rr);
-
- // For SRV records, automatically add the Address record(s) for the target host
- if (rr->resrec.rrtype == kDNSType_SRV)
- {
- for (rr2=m->ResourceRecords; rr2; rr2=rr2->next) // Scan list of resource records
- if (RRTypeIsAddressType(rr2->resrec.rrtype) && // For all address records (A/AAAA) ...
- ResourceRecordIsValidInterfaceAnswer(rr2, InterfaceID) && // ... which are valid for answer ...
- rr->resrec.rdatahash == rr2->resrec.namehash && // ... whose name is the name of the SRV target
- SameDomainName(&rr->resrec.rdata->u.srv.target, rr2->resrec.name))
- AddRecordToResponseList(nrpp, rr2, rr);
- }
- else if (RRTypeIsAddressType(rr->resrec.rrtype)) // For A or AAAA, put counterpart as additional
- {
- for (rr2=m->ResourceRecords; rr2; rr2=rr2->next) // Scan list of resource records
- if (RRTypeIsAddressType(rr2->resrec.rrtype) && // For all address records (A/AAAA) ...
- ResourceRecordIsValidInterfaceAnswer(rr2, InterfaceID) && // ... which are valid for answer ...
- rr->resrec.namehash == rr2->resrec.namehash && // ... and have the same name
- SameDomainName(rr->resrec.name, rr2->resrec.name))
- AddRecordToResponseList(nrpp, rr2, rr);
- }
- else if (rr->resrec.rrtype == kDNSType_PTR) // For service PTR, see if we want to add DeviceInfo record
- {
- if (ResourceRecordIsValidInterfaceAnswer(&m->DeviceInfo, InterfaceID) &&
- SameDomainLabel(rr->resrec.rdata->u.name.c, m->DeviceInfo.resrec.name->c))
- AddRecordToResponseList(nrpp, &m->DeviceInfo, rr);
- }
- }
- }
+{
+ AuthRecord *rr, *rr2;
+ for (rr=ResponseRecords; rr; rr=rr->NextResponse) // For each record we plan to put
+ {
+ // (Note: This is an "if", not a "while". If we add a record, we'll find it again
+ // later in the "for" loop, and we will follow further "additional" links then.)
+ if (rr->Additional1 && ResourceRecordIsValidInterfaceAnswer(rr->Additional1, InterfaceID))
+ AddRecordToResponseList(nrpp, rr->Additional1, rr);
+
+ if (rr->Additional2 && ResourceRecordIsValidInterfaceAnswer(rr->Additional2, InterfaceID))
+ AddRecordToResponseList(nrpp, rr->Additional2, rr);
+
+ // For SRV records, automatically add the Address record(s) for the target host
+ if (rr->resrec.rrtype == kDNSType_SRV)
+ {
+ for (rr2=m->ResourceRecords; rr2; rr2=rr2->next) // Scan list of resource records
+ if (RRTypeIsAddressType(rr2->resrec.rrtype) && // For all address records (A/AAAA) ...
+ ResourceRecordIsValidInterfaceAnswer(rr2, InterfaceID) && // ... which are valid for answer ...
+ rr->resrec.rdatahash == rr2->resrec.namehash && // ... whose name is the name of the SRV target
+ SameDomainName(&rr->resrec.rdata->u.srv.target, rr2->resrec.name))
+ AddRecordToResponseList(nrpp, rr2, rr);
+ }
+ else if (RRTypeIsAddressType(rr->resrec.rrtype)) // For A or AAAA, put counterpart as additional
+ {
+ for (rr2=m->ResourceRecords; rr2; rr2=rr2->next) // Scan list of resource records
+ if (RRTypeIsAddressType(rr2->resrec.rrtype) && // For all address records (A/AAAA) ...
+ ResourceRecordIsValidInterfaceAnswer(rr2, InterfaceID) && // ... which are valid for answer ...
+ rr->resrec.namehash == rr2->resrec.namehash && // ... and have the same name
+ SameDomainName(rr->resrec.name, rr2->resrec.name))
+ AddRecordToResponseList(nrpp, rr2, rr);
+ }
+ else if (rr->resrec.rrtype == kDNSType_PTR) // For service PTR, see if we want to add DeviceInfo record
+ {
+ if (ResourceRecordIsValidInterfaceAnswer(&m->DeviceInfo, InterfaceID) &&
+ SameDomainLabel(rr->resrec.rdata->u.name.c, m->DeviceInfo.resrec.name->c))
+ AddRecordToResponseList(nrpp, &m->DeviceInfo, rr);
+ }
+ }
+}
+
+mDNSlocal int AnonInfoSpace(AnonymousInfo *info)
+{
+ ResourceRecord *rr = info->nsec3RR;
+
+ // 2 bytes for compressed name + type (2) class (2) TTL (4) rdlength (2) rdata (n)
+ return (2 + 10 + rr->rdlength);
+}
mDNSlocal void SendDelayedUnicastResponse(mDNS *const m, const mDNSAddr *const dest, const mDNSInterfaceID InterfaceID)
- {
- AuthRecord *rr;
- AuthRecord *ResponseRecords = mDNSNULL;
- AuthRecord **nrp = &ResponseRecords;
- NetworkInterfaceInfo *intf = FirstInterfaceForID(m, InterfaceID);
-
- // Make a list of all our records that need to be unicast to this destination
- for (rr = m->ResourceRecords; rr; rr=rr->next)
- {
- // If we find we can no longer unicast this answer, clear ImmedUnicast
- if (rr->ImmedAnswer == mDNSInterfaceMark ||
- mDNSSameIPv4Address(rr->v4Requester, onesIPv4Addr) ||
- mDNSSameIPv6Address(rr->v6Requester, onesIPv6Addr) )
- rr->ImmedUnicast = mDNSfalse;
-
- if (rr->ImmedUnicast && rr->ImmedAnswer == InterfaceID)
- {
- if ((dest->type == mDNSAddrType_IPv4 && mDNSSameIPv4Address(rr->v4Requester, dest->ip.v4)) ||
- (dest->type == mDNSAddrType_IPv6 && mDNSSameIPv6Address(rr->v6Requester, dest->ip.v6)))
- {
- rr->ImmedAnswer = mDNSNULL; // Clear the state fields
- rr->ImmedUnicast = mDNSfalse;
- rr->v4Requester = zerov4Addr;
- rr->v6Requester = zerov6Addr;
-
- // Only sent records registered for P2P over P2P interfaces
- if (intf && !mDNSPlatformValidRecordForInterface(rr, intf))
- {
- LogInfo("SendDelayedUnicastResponse: Not sending %s, on %s", ARDisplayString(m, rr), InterfaceNameForID(m, InterfaceID));
- continue;
- }
-
- if (rr->NextResponse == mDNSNULL && nrp != &rr->NextResponse) // rr->NR_AnswerTo
- { rr->NR_AnswerTo = (mDNSu8*)~0; *nrp = rr; nrp = &rr->NextResponse; }
- }
- }
- }
-
- AddAdditionalsToResponseList(m, ResponseRecords, &nrp, InterfaceID);
-
- while (ResponseRecords)
- {
- mDNSu8 *responseptr = m->omsg.data;
- mDNSu8 *newptr;
- InitializeDNSMessage(&m->omsg.h, zeroID, ResponseFlags);
-
- // Put answers in the packet
- while (ResponseRecords && ResponseRecords->NR_AnswerTo)
- {
- rr = ResponseRecords;
- if (rr->resrec.RecordType & kDNSRecordTypeUniqueMask)
- rr->resrec.rrclass |= kDNSClass_UniqueRRSet; // Temporarily set the cache flush bit so PutResourceRecord will set it
- newptr = PutResourceRecord(&m->omsg, responseptr, &m->omsg.h.numAnswers, &rr->resrec);
- rr->resrec.rrclass &= ~kDNSClass_UniqueRRSet; // Make sure to clear cache flush bit back to normal state
- if (!newptr && m->omsg.h.numAnswers) break; // If packet full, send it now
- if (newptr) responseptr = newptr;
- ResponseRecords = rr->NextResponse;
- rr->NextResponse = mDNSNULL;
- rr->NR_AnswerTo = mDNSNULL;
- rr->NR_AdditionalTo = mDNSNULL;
- rr->RequireGoodbye = mDNStrue;
- }
-
- // Add additionals, if there's space
- while (ResponseRecords && !ResponseRecords->NR_AnswerTo)
- {
- rr = ResponseRecords;
- if (rr->resrec.RecordType & kDNSRecordTypeUniqueMask)
- rr->resrec.rrclass |= kDNSClass_UniqueRRSet; // Temporarily set the cache flush bit so PutResourceRecord will set it
- newptr = PutResourceRecord(&m->omsg, responseptr, &m->omsg.h.numAdditionals, &rr->resrec);
- rr->resrec.rrclass &= ~kDNSClass_UniqueRRSet; // Make sure to clear cache flush bit back to normal state
-
- if (newptr) responseptr = newptr;
- if (newptr && m->omsg.h.numAnswers) rr->RequireGoodbye = mDNStrue;
- else if (rr->resrec.RecordType & kDNSRecordTypeUniqueMask) rr->ImmedAnswer = mDNSInterfaceMark;
- ResponseRecords = rr->NextResponse;
- rr->NextResponse = mDNSNULL;
- rr->NR_AnswerTo = mDNSNULL;
- rr->NR_AdditionalTo = mDNSNULL;
- }
-
- if (m->omsg.h.numAnswers)
- mDNSSendDNSMessage(m, &m->omsg, responseptr, InterfaceID, mDNSNULL, dest, MulticastDNSPort, mDNSNULL, mDNSNULL);
- }
- }
+{
+ AuthRecord *rr;
+ AuthRecord *ResponseRecords = mDNSNULL;
+ AuthRecord **nrp = &ResponseRecords;
+ NetworkInterfaceInfo *intf = FirstInterfaceForID(m, InterfaceID);
+ int AnoninfoSpace = 0;
+
+ // Make a list of all our records that need to be unicast to this destination
+ for (rr = m->ResourceRecords; rr; rr=rr->next)
+ {
+ // If we find we can no longer unicast this answer, clear ImmedUnicast
+ if (rr->ImmedAnswer == mDNSInterfaceMark ||
+ mDNSSameIPv4Address(rr->v4Requester, onesIPv4Addr) ||
+ mDNSSameIPv6Address(rr->v6Requester, onesIPv6Addr) )
+ rr->ImmedUnicast = mDNSfalse;
+
+ if (rr->ImmedUnicast && rr->ImmedAnswer == InterfaceID)
+ {
+ if ((dest->type == mDNSAddrType_IPv4 && mDNSSameIPv4Address(rr->v4Requester, dest->ip.v4)) ||
+ (dest->type == mDNSAddrType_IPv6 && mDNSSameIPv6Address(rr->v6Requester, dest->ip.v6)))
+ {
+ rr->ImmedAnswer = mDNSNULL; // Clear the state fields
+ rr->ImmedUnicast = mDNSfalse;
+ rr->v4Requester = zerov4Addr;
+ rr->v6Requester = zerov6Addr;
+
+ // Only sent records registered for P2P over P2P interfaces
+ if (intf && !mDNSPlatformValidRecordForInterface(rr, intf))
+ {
+ LogInfo("SendDelayedUnicastResponse: Not sending %s, on %s", ARDisplayString(m, rr), InterfaceNameForID(m, InterfaceID));
+ continue;
+ }
+
+ if (rr->NextResponse == mDNSNULL && nrp != &rr->NextResponse) // rr->NR_AnswerTo
+ {
+ rr->NR_AnswerTo = NR_AnswerMulticast;
+ *nrp = rr;
+ nrp = &rr->NextResponse;
+ }
+ }
+ }
+ }
+
+ AddAdditionalsToResponseList(m, ResponseRecords, &nrp, InterfaceID);
+
+ while (ResponseRecords)
+ {
+ mDNSu8 *responseptr = m->omsg.data;
+ mDNSu8 *newptr;
+ InitializeDNSMessage(&m->omsg.h, zeroID, ResponseFlags);
+
+ // Put answers in the packet
+ while (ResponseRecords && ResponseRecords->NR_AnswerTo)
+ {
+ rr = ResponseRecords;
+ if (rr->resrec.AnonInfo)
+ {
+ AnoninfoSpace += AnonInfoSpace(rr->resrec.AnonInfo);
+ rr->resrec.AnonInfo->SendNow = mDNSInterfaceMark;
+ }
+ if (rr->resrec.RecordType & kDNSRecordTypeUniqueMask)
+ rr->resrec.rrclass |= kDNSClass_UniqueRRSet; // Temporarily set the cache flush bit so PutResourceRecord will set it
+
+ // Retract the limit by AnoninfoSpace which we need to put the AnoInfo option.
+ newptr = PutResourceRecordTTLWithLimit(&m->omsg, responseptr, &m->omsg.h.numAnswers, &rr->resrec, rr->resrec.rroriginalttl,
+ m->omsg.data + (AllowedRRSpace(&m->omsg) - AnoninfoSpace));
+
+ rr->resrec.rrclass &= ~kDNSClass_UniqueRRSet; // Make sure to clear cache flush bit back to normal state
+ if (!newptr && m->omsg.h.numAnswers)
+ {
+ break; // If packet full, send it now
+ }
+ if (newptr) responseptr = newptr;
+ ResponseRecords = rr->NextResponse;
+ rr->NextResponse = mDNSNULL;
+ rr->NR_AnswerTo = mDNSNULL;
+ rr->NR_AdditionalTo = mDNSNULL;
+ rr->RequireGoodbye = mDNStrue;
+ }
+
+ // We have reserved the space for AnonInfo option. PutResourceRecord uses the
+ // standard limit (AllowedRRSpace) and we should have space now.
+ for (rr = m->ResourceRecords; rr; rr=rr->next)
+ {
+ if (rr->resrec.AnonInfo && rr->resrec.AnonInfo->SendNow == mDNSInterfaceMark)
+ {
+ ResourceRecord *nsec3RR = rr->resrec.AnonInfo->nsec3RR;
+
+ newptr = PutResourceRecord(&m->omsg, responseptr, &m->omsg.h.numAuthorities, nsec3RR);
+ if (newptr)
+ {
+ responseptr = newptr;
+ debugf("SendDelayedUnicastResponse: Added NSEC3 Record %s on %p", RRDisplayString(m, nsec3RR), intf->InterfaceID);
+ }
+ else
+ {
+ // We allocated space and we should not fail. Don't break, we need to clear the SendNow flag.
+ LogMsg("SendDelayedUnicastResponse: ERROR!! Cannot Add NSEC3 Record %s on %p", RRDisplayString(m, nsec3RR), intf->InterfaceID);
+ }
+ rr->resrec.AnonInfo->SendNow = mDNSNULL;
+ }
+ }
+
+ // Add additionals, if there's space
+ while (ResponseRecords && !ResponseRecords->NR_AnswerTo)
+ {
+ rr = ResponseRecords;
+ if (rr->resrec.RecordType & kDNSRecordTypeUniqueMask)
+ rr->resrec.rrclass |= kDNSClass_UniqueRRSet; // Temporarily set the cache flush bit so PutResourceRecord will set it
+ newptr = PutResourceRecord(&m->omsg, responseptr, &m->omsg.h.numAdditionals, &rr->resrec);
+ rr->resrec.rrclass &= ~kDNSClass_UniqueRRSet; // Make sure to clear cache flush bit back to normal state
+
+ if (newptr) responseptr = newptr;
+ if (newptr && m->omsg.h.numAnswers) rr->RequireGoodbye = mDNStrue;
+ else if (rr->resrec.RecordType & kDNSRecordTypeUniqueMask) rr->ImmedAnswer = mDNSInterfaceMark;
+ ResponseRecords = rr->NextResponse;
+ rr->NextResponse = mDNSNULL;
+ rr->NR_AnswerTo = mDNSNULL;
+ rr->NR_AdditionalTo = mDNSNULL;
+ }
+
+ if (m->omsg.h.numAnswers)
+ mDNSSendDNSMessage(m, &m->omsg, responseptr, InterfaceID, mDNSNULL, dest, MulticastDNSPort, mDNSNULL, mDNSNULL, mDNSfalse);
+ }
+}
// CompleteDeregistration guarantees that on exit the record will have been cut from the m->ResourceRecords list
// and the client's mStatus_MemFree callback will have been invoked
mDNSexport void CompleteDeregistration(mDNS *const m, AuthRecord *rr)
- {
- LogInfo("CompleteDeregistration: called for Resource record %s", ARDisplayString(m, rr));
- // Clearing rr->RequireGoodbye signals mDNS_Deregister_internal() that
- // it should go ahead and immediately dispose of this registration
- rr->resrec.RecordType = kDNSRecordTypeShared;
- rr->RequireGoodbye = mDNSfalse;
- rr->WakeUp.HMAC = zeroEthAddr;
- if (rr->AnsweredLocalQ) { AnswerAllLocalQuestionsWithLocalAuthRecord(m, rr, mDNSfalse); rr->AnsweredLocalQ = mDNSfalse; }
- mDNS_Deregister_internal(m, rr, mDNS_Dereg_normal); // Don't touch rr after this
- }
+{
+ LogInfo("CompleteDeregistration: called for Resource record %s", ARDisplayString(m, rr));
+ // Clearing rr->RequireGoodbye signals mDNS_Deregister_internal() that
+ // it should go ahead and immediately dispose of this registration
+ rr->resrec.RecordType = kDNSRecordTypeShared;
+ rr->RequireGoodbye = mDNSfalse;
+ rr->WakeUp.HMAC = zeroEthAddr;
+ if (rr->AnsweredLocalQ) { AnswerAllLocalQuestionsWithLocalAuthRecord(m, rr, mDNSfalse); rr->AnsweredLocalQ = mDNSfalse; }
+ mDNS_Deregister_internal(m, rr, mDNS_Dereg_normal); // Don't touch rr after this
+}
// DiscardDeregistrations is used on shutdown and sleep to discard (forcibly and immediately)
// any deregistering records that remain in the m->ResourceRecords list.
// which may change the record list and/or question list.
// Any code walking either list must use the CurrentQuestion and/or CurrentRecord mechanism to protect against this.
mDNSlocal void DiscardDeregistrations(mDNS *const m)
- {
- if (m->CurrentRecord)
- LogMsg("DiscardDeregistrations ERROR m->CurrentRecord already set %s", ARDisplayString(m, m->CurrentRecord));
- m->CurrentRecord = m->ResourceRecords;
-
- while (m->CurrentRecord)
- {
- AuthRecord *rr = m->CurrentRecord;
- if (!AuthRecord_uDNS(rr) && rr->resrec.RecordType == kDNSRecordTypeDeregistering)
- CompleteDeregistration(m, rr); // Don't touch rr after this
- else
- m->CurrentRecord = rr->next;
- }
- }
+{
+ if (m->CurrentRecord)
+ LogMsg("DiscardDeregistrations ERROR m->CurrentRecord already set %s", ARDisplayString(m, m->CurrentRecord));
+ m->CurrentRecord = m->ResourceRecords;
+
+ while (m->CurrentRecord)
+ {
+ AuthRecord *rr = m->CurrentRecord;
+ if (!AuthRecord_uDNS(rr) && rr->resrec.RecordType == kDNSRecordTypeDeregistering)
+ CompleteDeregistration(m, rr); // Don't touch rr after this
+ else
+ m->CurrentRecord = rr->next;
+ }
+}
mDNSlocal mStatus GetLabelDecimalValue(const mDNSu8 *const src, mDNSu8 *dst)
- {
- int i, val = 0;
- if (src[0] < 1 || src[0] > 3) return(mStatus_Invalid);
- for (i=1; i<=src[0]; i++)
- {
- if (src[i] < '0' || src[i] > '9') return(mStatus_Invalid);
- val = val * 10 + src[i] - '0';
- }
- if (val > 255) return(mStatus_Invalid);
- *dst = (mDNSu8)val;
- return(mStatus_NoError);
- }
+{
+ int i, val = 0;
+ if (src[0] < 1 || src[0] > 3) return(mStatus_Invalid);
+ for (i=1; i<=src[0]; i++)
+ {
+ if (src[i] < '0' || src[i] > '9') return(mStatus_Invalid);
+ val = val * 10 + src[i] - '0';
+ }
+ if (val > 255) return(mStatus_Invalid);
+ *dst = (mDNSu8)val;
+ return(mStatus_NoError);
+}
mDNSlocal mStatus GetIPv4FromName(mDNSAddr *const a, const domainname *const name)
- {
- int skip = CountLabels(name) - 6;
- if (skip < 0) { LogMsg("GetIPFromName: Need six labels in IPv4 reverse mapping name %##s", name); return mStatus_Invalid; }
- if (GetLabelDecimalValue(SkipLeadingLabels(name, skip+3)->c, &a->ip.v4.b[0]) ||
- GetLabelDecimalValue(SkipLeadingLabels(name, skip+2)->c, &a->ip.v4.b[1]) ||
- GetLabelDecimalValue(SkipLeadingLabels(name, skip+1)->c, &a->ip.v4.b[2]) ||
- GetLabelDecimalValue(SkipLeadingLabels(name, skip+0)->c, &a->ip.v4.b[3])) return mStatus_Invalid;
- a->type = mDNSAddrType_IPv4;
- return(mStatus_NoError);
- }
+{
+ int skip = CountLabels(name) - 6;
+ if (skip < 0) { LogMsg("GetIPFromName: Need six labels in IPv4 reverse mapping name %##s", name); return mStatus_Invalid; }
+ if (GetLabelDecimalValue(SkipLeadingLabels(name, skip+3)->c, &a->ip.v4.b[0]) ||
+ GetLabelDecimalValue(SkipLeadingLabels(name, skip+2)->c, &a->ip.v4.b[1]) ||
+ GetLabelDecimalValue(SkipLeadingLabels(name, skip+1)->c, &a->ip.v4.b[2]) ||
+ GetLabelDecimalValue(SkipLeadingLabels(name, skip+0)->c, &a->ip.v4.b[3])) return mStatus_Invalid;
+ a->type = mDNSAddrType_IPv4;
+ return(mStatus_NoError);
+}
#define HexVal(X) ( ((X) >= '0' && (X) <= '9') ? ((X) - '0' ) : \
- ((X) >= 'A' && (X) <= 'F') ? ((X) - 'A' + 10) : \
- ((X) >= 'a' && (X) <= 'f') ? ((X) - 'a' + 10) : -1)
+ ((X) >= 'A' && (X) <= 'F') ? ((X) - 'A' + 10) : \
+ ((X) >= 'a' && (X) <= 'f') ? ((X) - 'a' + 10) : -1)
mDNSlocal mStatus GetIPv6FromName(mDNSAddr *const a, const domainname *const name)
- {
- int i, h, l;
- const domainname *n;
+{
+ int i, h, l;
+ const domainname *n;
- int skip = CountLabels(name) - 34;
- if (skip < 0) { LogMsg("GetIPFromName: Need 34 labels in IPv6 reverse mapping name %##s", name); return mStatus_Invalid; }
+ int skip = CountLabels(name) - 34;
+ if (skip < 0) { LogMsg("GetIPFromName: Need 34 labels in IPv6 reverse mapping name %##s", name); return mStatus_Invalid; }
- n = SkipLeadingLabels(name, skip);
- for (i=0; i<16; i++)
- {
- if (n->c[0] != 1) return mStatus_Invalid;
- l = HexVal(n->c[1]);
- n = (const domainname *)(n->c + 2);
+ n = SkipLeadingLabels(name, skip);
+ for (i=0; i<16; i++)
+ {
+ if (n->c[0] != 1) return mStatus_Invalid;
+ l = HexVal(n->c[1]);
+ n = (const domainname *)(n->c + 2);
- if (n->c[0] != 1) return mStatus_Invalid;
- h = HexVal(n->c[1]);
- n = (const domainname *)(n->c + 2);
+ if (n->c[0] != 1) return mStatus_Invalid;
+ h = HexVal(n->c[1]);
+ n = (const domainname *)(n->c + 2);
- if (l<0 || h<0) return mStatus_Invalid;
- a->ip.v6.b[15-i] = (mDNSu8)((h << 4) | l);
- }
+ if (l<0 || h<0) return mStatus_Invalid;
+ a->ip.v6.b[15-i] = (mDNSu8)((h << 4) | l);
+ }
- a->type = mDNSAddrType_IPv6;
- return(mStatus_NoError);
- }
+ a->type = mDNSAddrType_IPv6;
+ return(mStatus_NoError);
+}
mDNSlocal mDNSs32 ReverseMapDomainType(const domainname *const name)
- {
- int skip = CountLabels(name) - 2;
- if (skip >= 0)
- {
- const domainname *suffix = SkipLeadingLabels(name, skip);
- if (SameDomainName(suffix, (const domainname*)"\x7" "in-addr" "\x4" "arpa")) return mDNSAddrType_IPv4;
- if (SameDomainName(suffix, (const domainname*)"\x3" "ip6" "\x4" "arpa")) return mDNSAddrType_IPv6;
- }
- return(mDNSAddrType_None);
- }
+{
+ int skip = CountLabels(name) - 2;
+ if (skip >= 0)
+ {
+ const domainname *suffix = SkipLeadingLabels(name, skip);
+ if (SameDomainName(suffix, (const domainname*)"\x7" "in-addr" "\x4" "arpa")) return mDNSAddrType_IPv4;
+ if (SameDomainName(suffix, (const domainname*)"\x3" "ip6" "\x4" "arpa")) return mDNSAddrType_IPv6;
+ }
+ return(mDNSAddrType_None);
+}
mDNSlocal void SendARP(mDNS *const m, const mDNSu8 op, const AuthRecord *const rr,
- const mDNSv4Addr *const spa, const mDNSEthAddr *const tha, const mDNSv4Addr *const tpa, const mDNSEthAddr *const dst)
- {
- int i;
- mDNSu8 *ptr = m->omsg.data;
- NetworkInterfaceInfo *intf = FirstInterfaceForID(m, rr->resrec.InterfaceID);
- if (!intf) { LogMsg("SendARP: No interface with InterfaceID %p found %s", rr->resrec.InterfaceID, ARDisplayString(m,rr)); return; }
+ const mDNSv4Addr *const spa, const mDNSEthAddr *const tha, const mDNSv4Addr *const tpa, const mDNSEthAddr *const dst)
+{
+ int i;
+ mDNSu8 *ptr = m->omsg.data;
+ NetworkInterfaceInfo *intf = FirstInterfaceForID(m, rr->resrec.InterfaceID);
+ if (!intf) { LogMsg("SendARP: No interface with InterfaceID %p found %s", rr->resrec.InterfaceID, ARDisplayString(m,rr)); return; }
- // 0x00 Destination address
- for (i=0; i<6; i++) *ptr++ = dst->b[i];
+ // 0x00 Destination address
+ for (i=0; i<6; i++) *ptr++ = dst->b[i];
- // 0x06 Source address (Note: Since we don't currently set the BIOCSHDRCMPLT option, BPF will fill in the real interface address for us)
- for (i=0; i<6; i++) *ptr++ = intf->MAC.b[0];
+ // 0x06 Source address (Note: Since we don't currently set the BIOCSHDRCMPLT option, BPF will fill in the real interface address for us)
+ for (i=0; i<6; i++) *ptr++ = intf->MAC.b[0];
- // 0x0C ARP Ethertype (0x0806)
- *ptr++ = 0x08; *ptr++ = 0x06;
+ // 0x0C ARP Ethertype (0x0806)
+ *ptr++ = 0x08; *ptr++ = 0x06;
- // 0x0E ARP header
- *ptr++ = 0x00; *ptr++ = 0x01; // Hardware address space; Ethernet = 1
- *ptr++ = 0x08; *ptr++ = 0x00; // Protocol address space; IP = 0x0800
- *ptr++ = 6; // Hardware address length
- *ptr++ = 4; // Protocol address length
- *ptr++ = 0x00; *ptr++ = op; // opcode; Request = 1, Response = 2
+ // 0x0E ARP header
+ *ptr++ = 0x00; *ptr++ = 0x01; // Hardware address space; Ethernet = 1
+ *ptr++ = 0x08; *ptr++ = 0x00; // Protocol address space; IP = 0x0800
+ *ptr++ = 6; // Hardware address length
+ *ptr++ = 4; // Protocol address length
+ *ptr++ = 0x00; *ptr++ = op; // opcode; Request = 1, Response = 2
- // 0x16 Sender hardware address (our MAC address)
- for (i=0; i<6; i++) *ptr++ = intf->MAC.b[i];
+ // 0x16 Sender hardware address (our MAC address)
+ for (i=0; i<6; i++) *ptr++ = intf->MAC.b[i];
- // 0x1C Sender protocol address
- for (i=0; i<4; i++) *ptr++ = spa->b[i];
+ // 0x1C Sender protocol address
+ for (i=0; i<4; i++) *ptr++ = spa->b[i];
- // 0x20 Target hardware address
- for (i=0; i<6; i++) *ptr++ = tha->b[i];
+ // 0x20 Target hardware address
+ for (i=0; i<6; i++) *ptr++ = tha->b[i];
- // 0x26 Target protocol address
- for (i=0; i<4; i++) *ptr++ = tpa->b[i];
+ // 0x26 Target protocol address
+ for (i=0; i<4; i++) *ptr++ = tpa->b[i];
- // 0x2A Total ARP Packet length 42 bytes
- mDNSPlatformSendRawPacket(m->omsg.data, ptr, rr->resrec.InterfaceID);
- }
+ // 0x2A Total ARP Packet length 42 bytes
+ mDNSPlatformSendRawPacket(m->omsg.data, ptr, rr->resrec.InterfaceID);
+}
mDNSlocal mDNSu16 CheckSum(const void *const data, mDNSs32 length, mDNSu32 sum)
- {
- const mDNSu16 *ptr = data;
- while (length > 0) { length -= 2; sum += *ptr++; }
- sum = (sum & 0xFFFF) + (sum >> 16);
- sum = (sum & 0xFFFF) + (sum >> 16);
- return(sum != 0xFFFF ? sum : 0);
- }
+{
+ const mDNSu16 *ptr = data;
+ while (length > 0) { length -= 2; sum += *ptr++; }
+ sum = (sum & 0xFFFF) + (sum >> 16);
+ sum = (sum & 0xFFFF) + (sum >> 16);
+ return(sum != 0xFFFF ? sum : 0);
+}
mDNSlocal mDNSu16 IPv6CheckSum(const mDNSv6Addr *const src, const mDNSv6Addr *const dst, const mDNSu8 protocol, const void *const data, const mDNSu32 length)
- {
- IPv6PseudoHeader ph;
- ph.src = *src;
- ph.dst = *dst;
- ph.len.b[0] = length >> 24;
- ph.len.b[1] = length >> 16;
- ph.len.b[2] = length >> 8;
- ph.len.b[3] = length;
- ph.pro.b[0] = 0;
- ph.pro.b[1] = 0;
- ph.pro.b[2] = 0;
- ph.pro.b[3] = protocol;
- return CheckSum(&ph, sizeof(ph), CheckSum(data, length, 0));
- }
+{
+ IPv6PseudoHeader ph;
+ ph.src = *src;
+ ph.dst = *dst;
+ ph.len.b[0] = length >> 24;
+ ph.len.b[1] = length >> 16;
+ ph.len.b[2] = length >> 8;
+ ph.len.b[3] = length;
+ ph.pro.b[0] = 0;
+ ph.pro.b[1] = 0;
+ ph.pro.b[2] = 0;
+ ph.pro.b[3] = protocol;
+ return CheckSum(&ph, sizeof(ph), CheckSum(data, length, 0));
+}
mDNSlocal void SendNDP(mDNS *const m, const mDNSu8 op, const mDNSu8 flags, const AuthRecord *const rr,
- const mDNSv6Addr *const spa, const mDNSEthAddr *const tha, const mDNSv6Addr *const tpa, const mDNSEthAddr *const dst)
- {
- int i;
- mDNSOpaque16 checksum;
- mDNSu8 *ptr = m->omsg.data;
- // Some recipient hosts seem to ignore Neighbor Solicitations if the IPv6-layer destination address is not the
- // appropriate IPv6 solicited node multicast address, so we use that IPv6-layer destination address, even though
- // at the Ethernet-layer we unicast the packet to the intended target, to avoid wasting network bandwidth.
- const mDNSv6Addr mc = { { 0xFF,0x02,0x00,0x00, 0,0,0,0, 0,0,0,1, 0xFF,tpa->b[0xD],tpa->b[0xE],tpa->b[0xF] } };
- const mDNSv6Addr *const v6dst = (op == NDP_Sol) ? &mc : tpa;
- NetworkInterfaceInfo *intf = FirstInterfaceForID(m, rr->resrec.InterfaceID);
- if (!intf) { LogMsg("SendNDP: No interface with InterfaceID %p found %s", rr->resrec.InterfaceID, ARDisplayString(m,rr)); return; }
-
- // 0x00 Destination address
- for (i=0; i<6; i++) *ptr++ = dst->b[i];
- // Right now we only send Neighbor Solicitations to verify whether the host we're proxying for has gone to sleep yet.
- // Since we know who we're looking for, we send it via Ethernet-layer unicast, rather than bothering every host on the
- // link with a pointless link-layer multicast.
- // Should we want to send traditional Neighbor Solicitations in the future, where we really don't know in advance what
- // Ethernet-layer address we're looking for, we'll need to send to the appropriate Ethernet-layer multicast address:
- // *ptr++ = 0x33;
- // *ptr++ = 0x33;
- // *ptr++ = 0xFF;
- // *ptr++ = tpa->b[0xD];
- // *ptr++ = tpa->b[0xE];
- // *ptr++ = tpa->b[0xF];
-
- // 0x06 Source address (Note: Since we don't currently set the BIOCSHDRCMPLT option, BPF will fill in the real interface address for us)
- for (i=0; i<6; i++) *ptr++ = (tha ? *tha : intf->MAC).b[i];
-
- // 0x0C IPv6 Ethertype (0x86DD)
- *ptr++ = 0x86; *ptr++ = 0xDD;
-
- // 0x0E IPv6 header
- *ptr++ = 0x60; *ptr++ = 0x00; *ptr++ = 0x00; *ptr++ = 0x00; // Version, Traffic Class, Flow Label
- *ptr++ = 0x00; *ptr++ = 0x20; // Length
- *ptr++ = 0x3A; // Protocol == ICMPv6
- *ptr++ = 0xFF; // Hop Limit
-
- // 0x16 Sender IPv6 address
- for (i=0; i<16; i++) *ptr++ = spa->b[i];
-
- // 0x26 Destination IPv6 address
- for (i=0; i<16; i++) *ptr++ = v6dst->b[i];
-
- // 0x36 NDP header
- *ptr++ = op; // 0x87 == Neighbor Solicitation, 0x88 == Neighbor Advertisement
- *ptr++ = 0x00; // Code
- *ptr++ = 0x00; *ptr++ = 0x00; // Checksum placeholder (0x38, 0x39)
- *ptr++ = flags;
- *ptr++ = 0x00; *ptr++ = 0x00; *ptr++ = 0x00;
-
- if (op == NDP_Sol) // Neighbor Solicitation. The NDP "target" is the address we seek.
- {
- // 0x3E NDP target.
- for (i=0; i<16; i++) *ptr++ = tpa->b[i];
- // 0x4E Source Link-layer Address
- // <http://www.ietf.org/rfc/rfc2461.txt>
- // MUST NOT be included when the source IP address is the unspecified address.
- // Otherwise, on link layers that have addresses this option MUST be included
- // in multicast solicitations and SHOULD be included in unicast solicitations.
- if (!mDNSIPv6AddressIsZero(*spa))
- {
- *ptr++ = NDP_SrcLL; // Option Type 1 == Source Link-layer Address
- *ptr++ = 0x01; // Option length 1 (in units of 8 octets)
- for (i=0; i<6; i++) *ptr++ = (tha ? *tha : intf->MAC).b[i];
- }
- }
- else // Neighbor Advertisement. The NDP "target" is the address we're giving information about.
- {
- // 0x3E NDP target.
- for (i=0; i<16; i++) *ptr++ = spa->b[i];
- // 0x4E Target Link-layer Address
- *ptr++ = NDP_TgtLL; // Option Type 2 == Target Link-layer Address
- *ptr++ = 0x01; // Option length 1 (in units of 8 octets)
- for (i=0; i<6; i++) *ptr++ = (tha ? *tha : intf->MAC).b[i];
- }
-
- // 0x4E or 0x56 Total NDP Packet length 78 or 86 bytes
- m->omsg.data[0x13] = ptr - &m->omsg.data[0x36]; // Compute actual length
- checksum.NotAnInteger = ~IPv6CheckSum(spa, v6dst, 0x3A, &m->omsg.data[0x36], m->omsg.data[0x13]);
- m->omsg.data[0x38] = checksum.b[0];
- m->omsg.data[0x39] = checksum.b[1];
-
- mDNSPlatformSendRawPacket(m->omsg.data, ptr, rr->resrec.InterfaceID);
- }
+ const mDNSv6Addr *const spa, const mDNSEthAddr *const tha, const mDNSv6Addr *const tpa, const mDNSEthAddr *const dst)
+{
+ int i;
+ mDNSOpaque16 checksum;
+ mDNSu8 *ptr = m->omsg.data;
+ // Some recipient hosts seem to ignore Neighbor Solicitations if the IPv6-layer destination address is not the
+ // appropriate IPv6 solicited node multicast address, so we use that IPv6-layer destination address, even though
+ // at the Ethernet-layer we unicast the packet to the intended target, to avoid wasting network bandwidth.
+ const mDNSv6Addr mc = { { 0xFF,0x02,0x00,0x00, 0,0,0,0, 0,0,0,1, 0xFF,tpa->b[0xD],tpa->b[0xE],tpa->b[0xF] } };
+ const mDNSv6Addr *const v6dst = (op == NDP_Sol) ? &mc : tpa;
+ NetworkInterfaceInfo *intf = FirstInterfaceForID(m, rr->resrec.InterfaceID);
+ if (!intf) { LogMsg("SendNDP: No interface with InterfaceID %p found %s", rr->resrec.InterfaceID, ARDisplayString(m,rr)); return; }
+
+ // 0x00 Destination address
+ for (i=0; i<6; i++) *ptr++ = dst->b[i];
+ // Right now we only send Neighbor Solicitations to verify whether the host we're proxying for has gone to sleep yet.
+ // Since we know who we're looking for, we send it via Ethernet-layer unicast, rather than bothering every host on the
+ // link with a pointless link-layer multicast.
+ // Should we want to send traditional Neighbor Solicitations in the future, where we really don't know in advance what
+ // Ethernet-layer address we're looking for, we'll need to send to the appropriate Ethernet-layer multicast address:
+ // *ptr++ = 0x33;
+ // *ptr++ = 0x33;
+ // *ptr++ = 0xFF;
+ // *ptr++ = tpa->b[0xD];
+ // *ptr++ = tpa->b[0xE];
+ // *ptr++ = tpa->b[0xF];
+
+ // 0x06 Source address (Note: Since we don't currently set the BIOCSHDRCMPLT option, BPF will fill in the real interface address for us)
+ for (i=0; i<6; i++) *ptr++ = (tha ? *tha : intf->MAC).b[i];
+
+ // 0x0C IPv6 Ethertype (0x86DD)
+ *ptr++ = 0x86; *ptr++ = 0xDD;
+
+ // 0x0E IPv6 header
+ *ptr++ = 0x60; *ptr++ = 0x00; *ptr++ = 0x00; *ptr++ = 0x00; // Version, Traffic Class, Flow Label
+ *ptr++ = 0x00; *ptr++ = 0x20; // Length
+ *ptr++ = 0x3A; // Protocol == ICMPv6
+ *ptr++ = 0xFF; // Hop Limit
+
+ // 0x16 Sender IPv6 address
+ for (i=0; i<16; i++) *ptr++ = spa->b[i];
+
+ // 0x26 Destination IPv6 address
+ for (i=0; i<16; i++) *ptr++ = v6dst->b[i];
+
+ // 0x36 NDP header
+ *ptr++ = op; // 0x87 == Neighbor Solicitation, 0x88 == Neighbor Advertisement
+ *ptr++ = 0x00; // Code
+ *ptr++ = 0x00; *ptr++ = 0x00; // Checksum placeholder (0x38, 0x39)
+ *ptr++ = flags;
+ *ptr++ = 0x00; *ptr++ = 0x00; *ptr++ = 0x00;
+
+ if (op == NDP_Sol) // Neighbor Solicitation. The NDP "target" is the address we seek.
+ {
+ // 0x3E NDP target.
+ for (i=0; i<16; i++) *ptr++ = tpa->b[i];
+ // 0x4E Source Link-layer Address
+ // <http://www.ietf.org/rfc/rfc2461.txt>
+ // MUST NOT be included when the source IP address is the unspecified address.
+ // Otherwise, on link layers that have addresses this option MUST be included
+ // in multicast solicitations and SHOULD be included in unicast solicitations.
+ if (!mDNSIPv6AddressIsZero(*spa))
+ {
+ *ptr++ = NDP_SrcLL; // Option Type 1 == Source Link-layer Address
+ *ptr++ = 0x01; // Option length 1 (in units of 8 octets)
+ for (i=0; i<6; i++) *ptr++ = (tha ? *tha : intf->MAC).b[i];
+ }
+ }
+ else // Neighbor Advertisement. The NDP "target" is the address we're giving information about.
+ {
+ // 0x3E NDP target.
+ for (i=0; i<16; i++) *ptr++ = spa->b[i];
+ // 0x4E Target Link-layer Address
+ *ptr++ = NDP_TgtLL; // Option Type 2 == Target Link-layer Address
+ *ptr++ = 0x01; // Option length 1 (in units of 8 octets)
+ for (i=0; i<6; i++) *ptr++ = (tha ? *tha : intf->MAC).b[i];
+ }
+
+ // 0x4E or 0x56 Total NDP Packet length 78 or 86 bytes
+ m->omsg.data[0x13] = ptr - &m->omsg.data[0x36]; // Compute actual length
+ checksum.NotAnInteger = ~IPv6CheckSum(spa, v6dst, 0x3A, &m->omsg.data[0x36], m->omsg.data[0x13]);
+ m->omsg.data[0x38] = checksum.b[0];
+ m->omsg.data[0x39] = checksum.b[1];
+
+ mDNSPlatformSendRawPacket(m->omsg.data, ptr, rr->resrec.InterfaceID);
+}
+
+mDNSlocal void SetupTracerOpt(const mDNS *const m, rdataOPT *const Trace)
+{
+ mDNSu32 DNS_VERS = _DNS_SD_H;
+ Trace->u.tracer.platf = m->mDNS_plat;
+ Trace->u.tracer.mDNSv = DNS_VERS;
+
+ Trace->opt = kDNSOpt_Trace;
+ Trace->optlen = DNSOpt_TraceData_Space - 4;
+}
mDNSlocal void SetupOwnerOpt(const mDNS *const m, const NetworkInterfaceInfo *const intf, rdataOPT *const owner)
- {
- owner->u.owner.vers = 0;
- owner->u.owner.seq = m->SleepSeqNum;
- owner->u.owner.HMAC = m->PrimaryMAC;
- owner->u.owner.IMAC = intf->MAC;
- owner->u.owner.password = zeroEthAddr;
-
- // Don't try to compute the optlen until *after* we've set up the data fields
- // Right now the DNSOpt_Owner_Space macro does not depend on the owner->u.owner being set up correctly, but in the future it might
- owner->opt = kDNSOpt_Owner;
- owner->optlen = DNSOpt_Owner_Space(&m->PrimaryMAC, &intf->MAC) - 4;
- }
+{
+ owner->u.owner.vers = 0;
+ owner->u.owner.seq = m->SleepSeqNum;
+ owner->u.owner.HMAC = m->PrimaryMAC;
+ owner->u.owner.IMAC = intf->MAC;
+ owner->u.owner.password = zeroEthAddr;
+
+ // Don't try to compute the optlen until *after* we've set up the data fields
+ // Right now the DNSOpt_Owner_Space macro does not depend on the owner->u.owner being set up correctly, but in the future it might
+ owner->opt = kDNSOpt_Owner;
+ owner->optlen = DNSOpt_Owner_Space(&m->PrimaryMAC, &intf->MAC) - 4;
+}
mDNSlocal void GrantUpdateCredit(AuthRecord *rr)
- {
- if (++rr->UpdateCredits >= kMaxUpdateCredits) rr->NextUpdateCredit = 0;
- else rr->NextUpdateCredit = NonZeroTime(rr->NextUpdateCredit + kUpdateCreditRefreshInterval);
- }
+{
+ if (++rr->UpdateCredits >= kMaxUpdateCredits) rr->NextUpdateCredit = 0;
+ else rr->NextUpdateCredit = NonZeroTime(rr->NextUpdateCredit + kUpdateCreditRefreshInterval);
+}
+
+mDNSlocal mDNSBool ShouldSendGoodbyesBeforeSleep(mDNS *const m, const NetworkInterfaceInfo *intf, AuthRecord *rr)
+{
+ // If there are no sleep proxies, we set the state to SleepState_Sleeping explicitly
+ // and hence there is no need to check for Transfering state. But if we have sleep
+ // proxies and partially sending goodbyes for some records, we will be in Transfering
+ // state and hence need to make sure that we send goodbyes in that case too. Checking whether
+ // we are not awake handles both cases.
+ if ((rr->AuthFlags & AuthFlagsWakeOnly) && (m->SleepState != SleepState_Awake))
+ {
+ debugf("ShouldSendGoodbyesBeforeSleep: marking for goodbye", ARDisplayString(m, rr));
+ return mDNStrue;
+ }
+
+ if (m->SleepState != SleepState_Sleeping)
+ return mDNSfalse;
+
+ // If we are going to sleep and in SleepState_Sleeping, SendGoodbyes on the interface tell you
+ // whether you can send goodbyes or not.
+ if (!intf->SendGoodbyes)
+ {
+ debugf("ShouldSendGoodbyesBeforeSleep: not sending goodbye %s, int %p", ARDisplayString(m, rr), intf->InterfaceID);
+ return mDNSfalse;
+ }
+ else
+ {
+ debugf("ShouldSendGoodbyesBeforeSleep: sending goodbye %s, int %p", ARDisplayString(m, rr), intf->InterfaceID);
+ return mDNStrue;
+ }
+}
// Note about acceleration of announcements to facilitate automatic coalescing of
// multiple independent threads of announcements into a single synchronized thread:
// the record list and/or question list.
// Any code walking either list must use the CurrentQuestion and/or CurrentRecord mechanism to protect against this.
mDNSlocal void SendResponses(mDNS *const m)
- {
- int pktcount = 0;
- AuthRecord *rr, *r2;
- mDNSs32 maxExistingAnnounceInterval = 0;
- const NetworkInterfaceInfo *intf = GetFirstActiveInterface(m->HostInterfaces);
-
- m->NextScheduledResponse = m->timenow + 0x78000000;
-
- if (m->SleepState == SleepState_Transferring) RetrySPSRegistrations(m);
-
- for (rr = m->ResourceRecords; rr; rr=rr->next)
- if (rr->ImmedUnicast)
- {
- mDNSAddr v4 = { mDNSAddrType_IPv4, {{{0}}} };
- mDNSAddr v6 = { mDNSAddrType_IPv6, {{{0}}} };
- v4.ip.v4 = rr->v4Requester;
- v6.ip.v6 = rr->v6Requester;
- if (!mDNSIPv4AddressIsZero(rr->v4Requester)) SendDelayedUnicastResponse(m, &v4, rr->ImmedAnswer);
- if (!mDNSIPv6AddressIsZero(rr->v6Requester)) SendDelayedUnicastResponse(m, &v6, rr->ImmedAnswer);
- if (rr->ImmedUnicast)
- {
- LogMsg("SendResponses: ERROR: rr->ImmedUnicast still set: %s", ARDisplayString(m, rr));
- rr->ImmedUnicast = mDNSfalse;
- }
- }
-
- // ***
- // *** 1. Setup: Set the SendRNow and ImmedAnswer fields to indicate which interface(s) the records need to be sent on
- // ***
-
- // Run through our list of records, and decide which ones we're going to announce on all interfaces
- for (rr = m->ResourceRecords; rr; rr=rr->next)
- {
- while (rr->NextUpdateCredit && m->timenow - rr->NextUpdateCredit >= 0) GrantUpdateCredit(rr);
- if (TimeToAnnounceThisRecord(rr, m->timenow))
- {
- if (rr->resrec.RecordType == kDNSRecordTypeDeregistering)
- {
- if (!rr->WakeUp.HMAC.l[0])
- {
- if (rr->AnnounceCount) rr->ImmedAnswer = mDNSInterfaceMark; // Send goodbye packet on all interfaces
- }
- else
- {
- LogSPS("SendResponses: Sending wakeup %2d for %.6a %s", rr->AnnounceCount-3, &rr->WakeUp.IMAC, ARDisplayString(m, rr));
- SendWakeup(m, rr->resrec.InterfaceID, &rr->WakeUp.IMAC, &rr->WakeUp.password);
- for (r2 = rr; r2; r2=r2->next)
- if (r2->AnnounceCount && r2->resrec.InterfaceID == rr->resrec.InterfaceID && mDNSSameEthAddress(&r2->WakeUp.IMAC, &rr->WakeUp.IMAC))
- {
- // For now we only want to send a single Unsolicited Neighbor Advertisement restoring the address to the original
- // owner, because these packets can cause some IPv6 stacks to falsely conclude that there's an address conflict.
- if (r2->AddressProxy.type == mDNSAddrType_IPv6 && r2->AnnounceCount == WakeupCount)
- {
- LogSPS("NDP Announcement %2d Releasing traffic for H-MAC %.6a I-MAC %.6a %s",
- r2->AnnounceCount-3, &r2->WakeUp.HMAC, &r2->WakeUp.IMAC, ARDisplayString(m,r2));
- SendNDP(m, NDP_Adv, NDP_Override, r2, &r2->AddressProxy.ip.v6, &r2->WakeUp.IMAC, &AllHosts_v6, &AllHosts_v6_Eth);
- }
- r2->LastAPTime = m->timenow;
- // After 15 wakeups without success (maybe host has left the network) send three goodbyes instead
- if (--r2->AnnounceCount <= GoodbyeCount) r2->WakeUp.HMAC = zeroEthAddr;
- }
- }
- }
- else if (ResourceRecordIsValidAnswer(rr))
- {
- if (rr->AddressProxy.type)
- {
- rr->AnnounceCount--;
- rr->ThisAPInterval *= 2;
- rr->LastAPTime = m->timenow;
- if (rr->AddressProxy.type == mDNSAddrType_IPv4)
- {
- LogSPS("ARP Announcement %2d Capturing traffic for H-MAC %.6a I-MAC %.6a %s",
- rr->AnnounceCount, &rr->WakeUp.HMAC, &rr->WakeUp.IMAC, ARDisplayString(m,rr));
- SendARP(m, 1, rr, &rr->AddressProxy.ip.v4, &zeroEthAddr, &rr->AddressProxy.ip.v4, &onesEthAddr);
- }
- else if (rr->AddressProxy.type == mDNSAddrType_IPv6)
- {
- LogSPS("NDP Announcement %2d Capturing traffic for H-MAC %.6a I-MAC %.6a %s",
- rr->AnnounceCount, &rr->WakeUp.HMAC, &rr->WakeUp.IMAC, ARDisplayString(m,rr));
- SendNDP(m, NDP_Adv, NDP_Override, rr, &rr->AddressProxy.ip.v6, mDNSNULL, &AllHosts_v6, &AllHosts_v6_Eth);
- }
- }
- else
- {
- rr->ImmedAnswer = mDNSInterfaceMark; // Send on all interfaces
- if (maxExistingAnnounceInterval < rr->ThisAPInterval)
- maxExistingAnnounceInterval = rr->ThisAPInterval;
- if (rr->UpdateBlocked) rr->UpdateBlocked = 0;
- }
- }
- }
- }
-
- // Any interface-specific records we're going to send are marked as being sent on all appropriate interfaces (which is just one)
- // Eligible records that are more than half-way to their announcement time are accelerated
- for (rr = m->ResourceRecords; rr; rr=rr->next)
- if ((rr->resrec.InterfaceID && rr->ImmedAnswer) ||
- (rr->ThisAPInterval <= maxExistingAnnounceInterval &&
- TimeToAnnounceThisRecord(rr, m->timenow + rr->ThisAPInterval/2) &&
- !rr->AddressProxy.type && // Don't include ARP Annoucements when considering which records to accelerate
- ResourceRecordIsValidAnswer(rr)))
- rr->ImmedAnswer = mDNSInterfaceMark; // Send on all interfaces
-
- // When sending SRV records (particularly when announcing a new service) automatically add related Address record(s) as additionals
- // Note: Currently all address records are interface-specific, so it's safe to set ImmedAdditional to their InterfaceID,
- // which will be non-null. If by some chance there is an address record that's not interface-specific (should never happen)
- // then all that means is that it won't get sent -- which would not be the end of the world.
- for (rr = m->ResourceRecords; rr; rr=rr->next)
- {
- if (rr->ImmedAnswer && rr->resrec.rrtype == kDNSType_SRV)
- for (r2=m->ResourceRecords; r2; r2=r2->next) // Scan list of resource records
- if (RRTypeIsAddressType(r2->resrec.rrtype) && // For all address records (A/AAAA) ...
- ResourceRecordIsValidAnswer(r2) && // ... which are valid for answer ...
- rr->LastMCTime - r2->LastMCTime >= 0 && // ... which we have not sent recently ...
- rr->resrec.rdatahash == r2->resrec.namehash && // ... whose name is the name of the SRV target
- SameDomainName(&rr->resrec.rdata->u.srv.target, r2->resrec.name) &&
- (rr->ImmedAnswer == mDNSInterfaceMark || rr->ImmedAnswer == r2->resrec.InterfaceID))
- r2->ImmedAdditional = r2->resrec.InterfaceID; // ... then mark this address record for sending too
- // We also make sure we send the DeviceInfo TXT record too, if necessary
- // We check for RecordType == kDNSRecordTypeShared because we don't want to tag the
- // DeviceInfo TXT record onto a goodbye packet (RecordType == kDNSRecordTypeDeregistering).
- if (rr->ImmedAnswer && rr->resrec.RecordType == kDNSRecordTypeShared && rr->resrec.rrtype == kDNSType_PTR)
- if (ResourceRecordIsValidAnswer(&m->DeviceInfo) && SameDomainLabel(rr->resrec.rdata->u.name.c, m->DeviceInfo.resrec.name->c))
- {
- if (!m->DeviceInfo.ImmedAnswer) m->DeviceInfo.ImmedAnswer = rr->ImmedAnswer;
- else m->DeviceInfo.ImmedAnswer = mDNSInterfaceMark;
- }
- }
-
- // If there's a record which is supposed to be unique that we're going to send, then make sure that we give
- // the whole RRSet as an atomic unit. That means that if we have any other records with the same name/type/class
- // then we need to mark them for sending too. Otherwise, if we set the kDNSClass_UniqueRRSet bit on a
- // record, then other RRSet members that have not been sent recently will get flushed out of client caches.
- // -- If a record is marked to be sent on a certain interface, make sure the whole set is marked to be sent on that interface
- // -- If any record is marked to be sent on all interfaces, make sure the whole set is marked to be sent on all interfaces
- for (rr = m->ResourceRecords; rr; rr=rr->next)
- if (rr->resrec.RecordType & kDNSRecordTypeUniqueMask)
- {
- if (rr->ImmedAnswer) // If we're sending this as answer, see that its whole RRSet is similarly marked
- {
- for (r2 = m->ResourceRecords; r2; r2=r2->next)
- if (ResourceRecordIsValidAnswer(r2))
- if (r2->ImmedAnswer != mDNSInterfaceMark &&
- r2->ImmedAnswer != rr->ImmedAnswer && SameResourceRecordSignature(r2, rr))
- r2->ImmedAnswer = !r2->ImmedAnswer ? rr->ImmedAnswer : mDNSInterfaceMark;
- }
- else if (rr->ImmedAdditional) // If we're sending this as additional, see that its whole RRSet is similarly marked
- {
- for (r2 = m->ResourceRecords; r2; r2=r2->next)
- if (ResourceRecordIsValidAnswer(r2))
- if (r2->ImmedAdditional != rr->ImmedAdditional && SameResourceRecordSignature(r2, rr))
- r2->ImmedAdditional = rr->ImmedAdditional;
- }
- }
-
- // Now set SendRNow state appropriately
- for (rr = m->ResourceRecords; rr; rr=rr->next)
- {
- if (rr->ImmedAnswer == mDNSInterfaceMark) // Sending this record on all appropriate interfaces
- {
- rr->SendRNow = !intf ? mDNSNULL : (rr->resrec.InterfaceID) ? rr->resrec.InterfaceID : intf->InterfaceID;
- rr->ImmedAdditional = mDNSNULL; // No need to send as additional if sending as answer
- rr->LastMCTime = m->timenow;
- rr->LastMCInterface = rr->ImmedAnswer;
- // If we're announcing this record, and it's at least half-way to its ordained time, then consider this announcement done
- if (TimeToAnnounceThisRecord(rr, m->timenow + rr->ThisAPInterval/2))
- {
- rr->AnnounceCount--;
- if (rr->resrec.RecordType != kDNSRecordTypeDeregistering)
- rr->ThisAPInterval *= 2;
- rr->LastAPTime = m->timenow;
- debugf("Announcing %##s (%s) %d", rr->resrec.name->c, DNSTypeName(rr->resrec.rrtype), rr->AnnounceCount);
- }
- }
- else if (rr->ImmedAnswer) // Else, just respond to a single query on single interface:
- {
- rr->SendRNow = rr->ImmedAnswer; // Just respond on that interface
- rr->ImmedAdditional = mDNSNULL; // No need to send as additional too
- rr->LastMCTime = m->timenow;
- rr->LastMCInterface = rr->ImmedAnswer;
- }
- SetNextAnnounceProbeTime(m, rr);
- //if (rr->SendRNow) LogMsg("%-15.4a %s", &rr->v4Requester, ARDisplayString(m, rr));
- }
-
- // ***
- // *** 2. Loop through interface list, sending records as appropriate
- // ***
-
- while (intf)
- {
- const int OwnerRecordSpace = (m->AnnounceOwner && intf->MAC.l[0]) ? DNSOpt_Header_Space + DNSOpt_Owner_Space(&m->PrimaryMAC, &intf->MAC) : 0;
- int numDereg = 0;
- int numAnnounce = 0;
- int numAnswer = 0;
- mDNSu8 *responseptr = m->omsg.data;
- mDNSu8 *newptr;
- InitializeDNSMessage(&m->omsg.h, zeroID, ResponseFlags);
-
- // First Pass. Look for:
- // 1. Deregistering records that need to send their goodbye packet
- // 2. Updated records that need to retract their old data
- // 3. Answers and announcements we need to send
- for (rr = m->ResourceRecords; rr; rr=rr->next)
- {
-
- // Skip this interface if the record InterfaceID is *Any and the record is not
- // appropriate for the interface type.
- if ((rr->SendRNow == intf->InterfaceID) &&
- ((rr->resrec.InterfaceID == mDNSInterface_Any) && !mDNSPlatformValidRecordForInterface(rr, intf)))
- {
- LogInfo("SendResponses: Not sending %s, on %s", ARDisplayString(m, rr), InterfaceNameForID(m, rr->SendRNow));
- rr->SendRNow = GetNextActiveInterfaceID(intf);
- }
- else if (rr->SendRNow == intf->InterfaceID)
- {
- RData *OldRData = rr->resrec.rdata;
- mDNSu16 oldrdlength = rr->resrec.rdlength;
- mDNSu8 active = (mDNSu8)
- (rr->resrec.RecordType != kDNSRecordTypeDeregistering &&
- (m->SleepState != SleepState_Sleeping || intf->SPSAddr[0].type || intf->SPSAddr[1].type || intf->SPSAddr[2].type));
- newptr = mDNSNULL;
- if (rr->NewRData && active)
- {
- // See if we should send a courtesy "goodbye" for the old data before we replace it.
- if (ResourceRecordIsValidAnswer(rr) && rr->resrec.RecordType == kDNSRecordTypeShared && rr->RequireGoodbye)
- {
- newptr = PutRR_OS_TTL(responseptr, &m->omsg.h.numAnswers, &rr->resrec, 0);
- if (newptr) { responseptr = newptr; numDereg++; rr->RequireGoodbye = mDNSfalse; }
- else continue; // If this packet is already too full to hold the goodbye for this record, skip it for now and we'll retry later
- }
- SetNewRData(&rr->resrec, rr->NewRData, rr->newrdlength);
- }
-
- if (rr->resrec.RecordType & kDNSRecordTypeUniqueMask)
- rr->resrec.rrclass |= kDNSClass_UniqueRRSet; // Temporarily set the cache flush bit so PutResourceRecord will set it
- newptr = PutRR_OS_TTL(responseptr, &m->omsg.h.numAnswers, &rr->resrec, active ? rr->resrec.rroriginalttl : 0);
- rr->resrec.rrclass &= ~kDNSClass_UniqueRRSet; // Make sure to clear cache flush bit back to normal state
- if (newptr)
- {
- responseptr = newptr;
- rr->RequireGoodbye = active;
- if (rr->resrec.RecordType == kDNSRecordTypeDeregistering) numDereg++;
- else if (rr->LastAPTime == m->timenow) numAnnounce++; else numAnswer++;
- }
-
- if (rr->NewRData && active)
- SetNewRData(&rr->resrec, OldRData, oldrdlength);
-
- // The first time through (pktcount==0), if this record is verified unique
- // (i.e. typically A, AAAA, SRV, TXT and reverse-mapping PTR), set the flag to add an NSEC too.
- if (!pktcount && active && (rr->resrec.RecordType & kDNSRecordTypeActiveUniqueMask) && !rr->SendNSECNow)
- rr->SendNSECNow = mDNSInterfaceMark;
-
- if (newptr) // If succeeded in sending, advance to next interface
- {
- // If sending on all interfaces, go to next interface; else we're finished now
- if (rr->ImmedAnswer == mDNSInterfaceMark && rr->resrec.InterfaceID == mDNSInterface_Any)
- rr->SendRNow = GetNextActiveInterfaceID(intf);
- else
- rr->SendRNow = mDNSNULL;
- }
- }
- }
-
- // Second Pass. Add additional records, if there's space.
- newptr = responseptr;
- for (rr = m->ResourceRecords; rr; rr=rr->next)
- if (rr->ImmedAdditional == intf->InterfaceID)
- if (ResourceRecordIsValidAnswer(rr))
- {
- // If we have at least one answer already in the packet, then plan to add additionals too
- mDNSBool SendAdditional = (m->omsg.h.numAnswers > 0);
-
- // If we're not planning to send any additionals, but this record is a unique one, then
- // make sure we haven't already sent any other members of its RRSet -- if we have, then they
- // will have had the cache flush bit set, so now we need to finish the job and send the rest.
- if (!SendAdditional && (rr->resrec.RecordType & kDNSRecordTypeUniqueMask))
- {
- const AuthRecord *a;
- for (a = m->ResourceRecords; a; a=a->next)
- if (a->LastMCTime == m->timenow &&
- a->LastMCInterface == intf->InterfaceID &&
- SameResourceRecordSignature(a, rr)) { SendAdditional = mDNStrue; break; }
- }
- if (!SendAdditional) // If we don't want to send this after all,
- rr->ImmedAdditional = mDNSNULL; // then cancel its ImmedAdditional field
- else if (newptr) // Else, try to add it if we can
- {
- // The first time through (pktcount==0), if this record is verified unique
- // (i.e. typically A, AAAA, SRV, TXT and reverse-mapping PTR), set the flag to add an NSEC too.
- if (!pktcount && (rr->resrec.RecordType & kDNSRecordTypeActiveUniqueMask) && !rr->SendNSECNow)
- rr->SendNSECNow = mDNSInterfaceMark;
-
- if (rr->resrec.RecordType & kDNSRecordTypeUniqueMask)
- rr->resrec.rrclass |= kDNSClass_UniqueRRSet; // Temporarily set the cache flush bit so PutResourceRecord will set it
- newptr = PutRR_OS(newptr, &m->omsg.h.numAdditionals, &rr->resrec);
- rr->resrec.rrclass &= ~kDNSClass_UniqueRRSet; // Make sure to clear cache flush bit back to normal state
- if (newptr)
- {
- responseptr = newptr;
- rr->ImmedAdditional = mDNSNULL;
- rr->RequireGoodbye = mDNStrue;
- // If we successfully put this additional record in the packet, we record LastMCTime & LastMCInterface.
- // This matters particularly in the case where we have more than one IPv6 (or IPv4) address, because otherwise,
- // when we see our own multicast with the cache flush bit set, if we haven't set LastMCTime, then we'll get
- // all concerned and re-announce our record again to make sure it doesn't get flushed from peer caches.
- rr->LastMCTime = m->timenow;
- rr->LastMCInterface = intf->InterfaceID;
- }
- }
- }
-
- // Third Pass. Add NSEC records, if there's space.
- // When we're generating an NSEC record in response to a specify query for that type
- // (recognized by rr->SendNSECNow == intf->InterfaceID) we should really put the NSEC in the Answer Section,
- // not Additional Section, but for now it's easier to handle both cases in this Additional Section loop here.
- for (rr = m->ResourceRecords; rr; rr=rr->next)
- if (rr->SendNSECNow == mDNSInterfaceMark || rr->SendNSECNow == intf->InterfaceID)
- {
- AuthRecord nsec;
- mDNS_SetupResourceRecord(&nsec, mDNSNULL, mDNSInterface_Any, kDNSType_NSEC, rr->resrec.rroriginalttl, kDNSRecordTypeUnique, AuthRecordAny, mDNSNULL, mDNSNULL);
- nsec.resrec.rrclass |= kDNSClass_UniqueRRSet;
- AssignDomainName(&nsec.namestorage, rr->resrec.name);
- mDNSPlatformMemZero(nsec.rdatastorage.u.nsec.bitmap, sizeof(nsec.rdatastorage.u.nsec.bitmap));
- for (r2 = m->ResourceRecords; r2; r2=r2->next)
- if (ResourceRecordIsValidAnswer(r2) && SameResourceRecordNameClassInterface(r2, rr))
- {
- if (r2->resrec.rrtype >= kDNSQType_ANY) { LogMsg("Can't create NSEC for record %s", ARDisplayString(m, r2)); break; }
- else nsec.rdatastorage.u.nsec.bitmap[r2->resrec.rrtype >> 3] |= 128 >> (r2->resrec.rrtype & 7);
- }
- newptr = responseptr;
- if (!r2) // If we successfully built our NSEC record, add it to the packet now
- {
- newptr = PutRR_OS(responseptr, &m->omsg.h.numAdditionals, &nsec.resrec);
- if (newptr) responseptr = newptr;
- }
-
- // If we successfully put the NSEC record, clear the SendNSECNow flag
- // If we consider this NSEC optional, then we unconditionally clear the SendNSECNow flag, even if we fail to put this additional record
- if (newptr || rr->SendNSECNow == mDNSInterfaceMark)
- {
- rr->SendNSECNow = mDNSNULL;
- // Run through remainder of list clearing SendNSECNow flag for all other records which would generate the same NSEC
- for (r2 = rr->next; r2; r2=r2->next)
- if (SameResourceRecordNameClassInterface(r2, rr))
- if (r2->SendNSECNow == mDNSInterfaceMark || r2->SendNSECNow == intf->InterfaceID)
- r2->SendNSECNow = mDNSNULL;
- }
- }
-
- if (m->omsg.h.numAnswers || m->omsg.h.numAdditionals)
- {
- // If we have data to send, add OWNER option if necessary, then send packet
-
- if (OwnerRecordSpace)
- {
- AuthRecord opt;
- mDNS_SetupResourceRecord(&opt, mDNSNULL, mDNSInterface_Any, kDNSType_OPT, kStandardTTL, kDNSRecordTypeKnownUnique, AuthRecordAny, mDNSNULL, mDNSNULL);
- opt.resrec.rrclass = NormalMaxDNSMessageData;
- opt.resrec.rdlength = sizeof(rdataOPT); // One option in this OPT record
- opt.resrec.rdestimate = sizeof(rdataOPT);
- SetupOwnerOpt(m, intf, &opt.resrec.rdata->u.opt[0]);
- newptr = PutResourceRecord(&m->omsg, responseptr, &m->omsg.h.numAdditionals, &opt.resrec);
- if (newptr) { responseptr = newptr; LogSPS("SendResponses put %s", ARDisplayString(m, &opt)); }
- else if (m->omsg.h.numAnswers + m->omsg.h.numAuthorities + m->omsg.h.numAdditionals == 1)
- LogSPS("SendResponses: No space in packet for Owner OPT record (%d/%d/%d/%d) %s",
- m->omsg.h.numQuestions, m->omsg.h.numAnswers, m->omsg.h.numAuthorities, m->omsg.h.numAdditionals, ARDisplayString(m, &opt));
- else
- LogMsg("SendResponses: How did we fail to have space for Owner OPT record (%d/%d/%d/%d) %s",
- m->omsg.h.numQuestions, m->omsg.h.numAnswers, m->omsg.h.numAuthorities, m->omsg.h.numAdditionals, ARDisplayString(m, &opt));
- }
-
- debugf("SendResponses: Sending %d Deregistration%s, %d Announcement%s, %d Answer%s, %d Additional%s on %p",
- numDereg, numDereg == 1 ? "" : "s",
- numAnnounce, numAnnounce == 1 ? "" : "s",
- numAnswer, numAnswer == 1 ? "" : "s",
- m->omsg.h.numAdditionals, m->omsg.h.numAdditionals == 1 ? "" : "s", intf->InterfaceID);
-
- if (intf->IPv4Available) mDNSSendDNSMessage(m, &m->omsg, responseptr, intf->InterfaceID, mDNSNULL, &AllDNSLinkGroup_v4, MulticastDNSPort, mDNSNULL, mDNSNULL);
- if (intf->IPv6Available) mDNSSendDNSMessage(m, &m->omsg, responseptr, intf->InterfaceID, mDNSNULL, &AllDNSLinkGroup_v6, MulticastDNSPort, mDNSNULL, mDNSNULL);
- if (!m->SuppressSending) m->SuppressSending = NonZeroTime(m->timenow + (mDNSPlatformOneSecond+9)/10);
- if (++pktcount >= 1000) { LogMsg("SendResponses exceeded loop limit %d: giving up", pktcount); break; }
- // There might be more things to send on this interface, so go around one more time and try again.
- }
- else // Nothing more to send on this interface; go to next
- {
- const NetworkInterfaceInfo *next = GetFirstActiveInterface(intf->next);
- #if MDNS_DEBUGMSGS && 0
- const char *const msg = next ? "SendResponses: Nothing more on %p; moving to %p" : "SendResponses: Nothing more on %p";
- debugf(msg, intf, next);
- #endif
- intf = next;
- pktcount = 0; // When we move to a new interface, reset packet count back to zero -- NSEC generation logic uses it
- }
- }
-
- // ***
- // *** 3. Cleanup: Now that everything is sent, call client callback functions, and reset state variables
- // ***
-
- if (m->CurrentRecord)
- LogMsg("SendResponses ERROR m->CurrentRecord already set %s", ARDisplayString(m, m->CurrentRecord));
- m->CurrentRecord = m->ResourceRecords;
- while (m->CurrentRecord)
- {
- rr = m->CurrentRecord;
- m->CurrentRecord = rr->next;
-
- if (rr->SendRNow)
- {
- if (rr->ARType != AuthRecordLocalOnly && rr->ARType != AuthRecordP2P)
- LogMsg("SendResponses: No active interface %p to send: %p %02X %s", rr->SendRNow, rr->resrec.InterfaceID, rr->resrec.RecordType, ARDisplayString(m, rr));
- rr->SendRNow = mDNSNULL;
- }
-
- if (rr->ImmedAnswer || rr->resrec.RecordType == kDNSRecordTypeDeregistering)
- {
- if (rr->NewRData) CompleteRDataUpdate(m, rr); // Update our rdata, clear the NewRData pointer, and return memory to the client
-
- if (rr->resrec.RecordType == kDNSRecordTypeDeregistering && rr->AnnounceCount == 0)
- {
- // For Unicast, when we get the response from the server, we will call CompleteDeregistration
- if (!AuthRecord_uDNS(rr)) CompleteDeregistration(m, rr); // Don't touch rr after this
- }
- else
- {
- rr->ImmedAnswer = mDNSNULL;
- rr->ImmedUnicast = mDNSfalse;
- rr->v4Requester = zerov4Addr;
- rr->v6Requester = zerov6Addr;
- }
- }
- }
- verbosedebugf("SendResponses: Next in %ld ticks", m->NextScheduledResponse - m->timenow);
- }
+{
+ int pktcount = 0;
+ AuthRecord *rr, *r2;
+ mDNSs32 maxExistingAnnounceInterval = 0;
+ const NetworkInterfaceInfo *intf = GetFirstActiveInterface(m->HostInterfaces);
+
+ m->NextScheduledResponse = m->timenow + 0x78000000;
+
+ if (m->SleepState == SleepState_Transferring) RetrySPSRegistrations(m);
+
+ for (rr = m->ResourceRecords; rr; rr=rr->next)
+ if (rr->ImmedUnicast)
+ {
+ mDNSAddr v4 = { mDNSAddrType_IPv4, {{{0}}} };
+ mDNSAddr v6 = { mDNSAddrType_IPv6, {{{0}}} };
+ v4.ip.v4 = rr->v4Requester;
+ v6.ip.v6 = rr->v6Requester;
+ if (!mDNSIPv4AddressIsZero(rr->v4Requester)) SendDelayedUnicastResponse(m, &v4, rr->ImmedAnswer);
+ if (!mDNSIPv6AddressIsZero(rr->v6Requester)) SendDelayedUnicastResponse(m, &v6, rr->ImmedAnswer);
+ if (rr->ImmedUnicast)
+ {
+ LogMsg("SendResponses: ERROR: rr->ImmedUnicast still set: %s", ARDisplayString(m, rr));
+ rr->ImmedUnicast = mDNSfalse;
+ }
+ }
+
+ // ***
+ // *** 1. Setup: Set the SendRNow and ImmedAnswer fields to indicate which interface(s) the records need to be sent on
+ // ***
+
+ // Run through our list of records, and decide which ones we're going to announce on all interfaces
+ for (rr = m->ResourceRecords; rr; rr=rr->next)
+ {
+ while (rr->NextUpdateCredit && m->timenow - rr->NextUpdateCredit >= 0) GrantUpdateCredit(rr);
+ if (TimeToAnnounceThisRecord(rr, m->timenow))
+ {
+ if (rr->resrec.RecordType == kDNSRecordTypeDeregistering)
+ {
+ if (!rr->WakeUp.HMAC.l[0])
+ {
+ if (rr->AnnounceCount) rr->ImmedAnswer = mDNSInterfaceMark; // Send goodbye packet on all interfaces
+ }
+ else
+ {
+ LogSPS("SendResponses: Sending wakeup %2d for %.6a %s", rr->AnnounceCount-3, &rr->WakeUp.IMAC, ARDisplayString(m, rr));
+ SendWakeup(m, rr->resrec.InterfaceID, &rr->WakeUp.IMAC, &rr->WakeUp.password);
+ for (r2 = rr; r2; r2=r2->next)
+ if (r2->AnnounceCount && r2->resrec.InterfaceID == rr->resrec.InterfaceID && mDNSSameEthAddress(&r2->WakeUp.IMAC, &rr->WakeUp.IMAC) &&
+ !mDNSSameEthAddress(&zeroEthAddr, &r2->WakeUp.HMAC))
+ {
+ // For now we only want to send a single Unsolicited Neighbor Advertisement restoring the address to the original
+ // owner, because these packets can cause some IPv6 stacks to falsely conclude that there's an address conflict.
+ if (r2->AddressProxy.type == mDNSAddrType_IPv6 && r2->AnnounceCount == WakeupCount)
+ {
+ LogSPS("NDP Announcement %2d Releasing traffic for H-MAC %.6a I-MAC %.6a %s",
+ r2->AnnounceCount-3, &r2->WakeUp.HMAC, &r2->WakeUp.IMAC, ARDisplayString(m,r2));
+ SendNDP(m, NDP_Adv, NDP_Override, r2, &r2->AddressProxy.ip.v6, &r2->WakeUp.IMAC, &AllHosts_v6, &AllHosts_v6_Eth);
+ }
+ r2->LastAPTime = m->timenow;
+ // After 15 wakeups without success (maybe host has left the network) send three goodbyes instead
+ if (--r2->AnnounceCount <= GoodbyeCount) r2->WakeUp.HMAC = zeroEthAddr;
+ }
+ }
+ }
+ else if (ResourceRecordIsValidAnswer(rr))
+ {
+ if (rr->AddressProxy.type)
+ {
+ if (!mDNSSameEthAddress(&zeroEthAddr, &rr->WakeUp.HMAC))
+ {
+ rr->AnnounceCount--;
+ rr->ThisAPInterval *= 2;
+ rr->LastAPTime = m->timenow;
+ if (rr->AddressProxy.type == mDNSAddrType_IPv4)
+ {
+ LogSPS("ARP Announcement %2d Capturing traffic for H-MAC %.6a I-MAC %.6a %s",
+ rr->AnnounceCount, &rr->WakeUp.HMAC, &rr->WakeUp.IMAC, ARDisplayString(m,rr));
+ SendARP(m, 1, rr, &rr->AddressProxy.ip.v4, &zeroEthAddr, &rr->AddressProxy.ip.v4, &onesEthAddr);
+ }
+ else if (rr->AddressProxy.type == mDNSAddrType_IPv6)
+ {
+ LogSPS("NDP Announcement %2d Capturing traffic for H-MAC %.6a I-MAC %.6a %s",
+ rr->AnnounceCount, &rr->WakeUp.HMAC, &rr->WakeUp.IMAC, ARDisplayString(m,rr));
+ SendNDP(m, NDP_Adv, NDP_Override, rr, &rr->AddressProxy.ip.v6, mDNSNULL, &AllHosts_v6, &AllHosts_v6_Eth);
+ }
+ }
+ }
+ else
+ {
+ rr->ImmedAnswer = mDNSInterfaceMark; // Send on all interfaces
+ if (maxExistingAnnounceInterval < rr->ThisAPInterval)
+ maxExistingAnnounceInterval = rr->ThisAPInterval;
+ if (rr->UpdateBlocked) rr->UpdateBlocked = 0;
+ }
+ }
+ }
+ }
+
+ // Any interface-specific records we're going to send are marked as being sent on all appropriate interfaces (which is just one)
+ // Eligible records that are more than half-way to their announcement time are accelerated
+ for (rr = m->ResourceRecords; rr; rr=rr->next)
+ if ((rr->resrec.InterfaceID && rr->ImmedAnswer) ||
+ (rr->ThisAPInterval <= maxExistingAnnounceInterval &&
+ TimeToAnnounceThisRecord(rr, m->timenow + rr->ThisAPInterval/2) &&
+ !rr->AddressProxy.type && // Don't include ARP Annoucements when considering which records to accelerate
+ ResourceRecordIsValidAnswer(rr)))
+ rr->ImmedAnswer = mDNSInterfaceMark; // Send on all interfaces
+
+ // When sending SRV records (particularly when announcing a new service) automatically add related Address record(s) as additionals
+ // Note: Currently all address records are interface-specific, so it's safe to set ImmedAdditional to their InterfaceID,
+ // which will be non-null. If by some chance there is an address record that's not interface-specific (should never happen)
+ // then all that means is that it won't get sent -- which would not be the end of the world.
+ for (rr = m->ResourceRecords; rr; rr=rr->next)
+ {
+ if (rr->ImmedAnswer && rr->resrec.rrtype == kDNSType_SRV)
+ for (r2=m->ResourceRecords; r2; r2=r2->next) // Scan list of resource records
+ if (RRTypeIsAddressType(r2->resrec.rrtype) && // For all address records (A/AAAA) ...
+ ResourceRecordIsValidAnswer(r2) && // ... which are valid for answer ...
+ rr->LastMCTime - r2->LastMCTime >= 0 && // ... which we have not sent recently ...
+ rr->resrec.rdatahash == r2->resrec.namehash && // ... whose name is the name of the SRV target
+ SameDomainName(&rr->resrec.rdata->u.srv.target, r2->resrec.name) &&
+ (rr->ImmedAnswer == mDNSInterfaceMark || rr->ImmedAnswer == r2->resrec.InterfaceID))
+ r2->ImmedAdditional = r2->resrec.InterfaceID; // ... then mark this address record for sending too
+ // We also make sure we send the DeviceInfo TXT record too, if necessary
+ // We check for RecordType == kDNSRecordTypeShared because we don't want to tag the
+ // DeviceInfo TXT record onto a goodbye packet (RecordType == kDNSRecordTypeDeregistering).
+ if (rr->ImmedAnswer && rr->resrec.RecordType == kDNSRecordTypeShared && rr->resrec.rrtype == kDNSType_PTR)
+ if (ResourceRecordIsValidAnswer(&m->DeviceInfo) && SameDomainLabel(rr->resrec.rdata->u.name.c, m->DeviceInfo.resrec.name->c))
+ {
+ if (!m->DeviceInfo.ImmedAnswer) m->DeviceInfo.ImmedAnswer = rr->ImmedAnswer;
+ else m->DeviceInfo.ImmedAnswer = mDNSInterfaceMark;
+ }
+ }
+
+ // If there's a record which is supposed to be unique that we're going to send, then make sure that we give
+ // the whole RRSet as an atomic unit. That means that if we have any other records with the same name/type/class
+ // then we need to mark them for sending too. Otherwise, if we set the kDNSClass_UniqueRRSet bit on a
+ // record, then other RRSet members that have not been sent recently will get flushed out of client caches.
+ // -- If a record is marked to be sent on a certain interface, make sure the whole set is marked to be sent on that interface
+ // -- If any record is marked to be sent on all interfaces, make sure the whole set is marked to be sent on all interfaces
+ for (rr = m->ResourceRecords; rr; rr=rr->next)
+ if (rr->resrec.RecordType & kDNSRecordTypeUniqueMask)
+ {
+ if (rr->ImmedAnswer) // If we're sending this as answer, see that its whole RRSet is similarly marked
+ {
+ for (r2 = m->ResourceRecords; r2; r2=r2->next)
+ if (ResourceRecordIsValidAnswer(r2))
+ if (r2->ImmedAnswer != mDNSInterfaceMark &&
+ r2->ImmedAnswer != rr->ImmedAnswer && SameResourceRecordSignature(r2, rr))
+ r2->ImmedAnswer = !r2->ImmedAnswer ? rr->ImmedAnswer : mDNSInterfaceMark;
+ }
+ else if (rr->ImmedAdditional) // If we're sending this as additional, see that its whole RRSet is similarly marked
+ {
+ for (r2 = m->ResourceRecords; r2; r2=r2->next)
+ if (ResourceRecordIsValidAnswer(r2))
+ if (r2->ImmedAdditional != rr->ImmedAdditional && SameResourceRecordSignature(r2, rr))
+ r2->ImmedAdditional = rr->ImmedAdditional;
+ }
+ }
+
+ // Now set SendRNow state appropriately
+ for (rr = m->ResourceRecords; rr; rr=rr->next)
+ {
+ if (rr->ImmedAnswer == mDNSInterfaceMark) // Sending this record on all appropriate interfaces
+ {
+ rr->SendRNow = !intf ? mDNSNULL : (rr->resrec.InterfaceID) ? rr->resrec.InterfaceID : intf->InterfaceID;
+ rr->ImmedAdditional = mDNSNULL; // No need to send as additional if sending as answer
+ rr->LastMCTime = m->timenow;
+ rr->LastMCInterface = rr->ImmedAnswer;
+ // If we're announcing this record, and it's at least half-way to its ordained time, then consider this announcement done
+ if (TimeToAnnounceThisRecord(rr, m->timenow + rr->ThisAPInterval/2))
+ {
+ rr->AnnounceCount--;
+ if (rr->resrec.RecordType != kDNSRecordTypeDeregistering)
+ rr->ThisAPInterval *= 2;
+ rr->LastAPTime = m->timenow;
+ debugf("Announcing %##s (%s) %d", rr->resrec.name->c, DNSTypeName(rr->resrec.rrtype), rr->AnnounceCount);
+ }
+ }
+ else if (rr->ImmedAnswer) // Else, just respond to a single query on single interface:
+ {
+ rr->SendRNow = rr->ImmedAnswer; // Just respond on that interface
+ rr->ImmedAdditional = mDNSNULL; // No need to send as additional too
+ rr->LastMCTime = m->timenow;
+ rr->LastMCInterface = rr->ImmedAnswer;
+ }
+ SetNextAnnounceProbeTime(m, rr);
+ //if (rr->SendRNow) LogMsg("%-15.4a %s", &rr->v4Requester, ARDisplayString(m, rr));
+ }
+
+ // ***
+ // *** 2. Loop through interface list, sending records as appropriate
+ // ***
+
+ while (intf)
+ {
+ int OwnerRecordSpace = (m->AnnounceOwner && intf->MAC.l[0]) ? DNSOpt_Header_Space + DNSOpt_Owner_Space(&m->PrimaryMAC, &intf->MAC) : 0;
+ int TraceRecordSpace = (mDNS_McastTracingEnabled && MDNS_TRACER) ? DNSOpt_Header_Space + DNSOpt_TraceData_Space : 0;
+ int numDereg = 0;
+ int numAnnounce = 0;
+ int numAnswer = 0;
+ int AnoninfoSpace = 0;
+ mDNSu8 *responseptr = m->omsg.data;
+ mDNSu8 *newptr;
+ InitializeDNSMessage(&m->omsg.h, zeroID, ResponseFlags);
+
+ // First Pass. Look for:
+ // 1. Deregistering records that need to send their goodbye packet
+ // 2. Updated records that need to retract their old data
+ // 3. Answers and announcements we need to send
+ for (rr = m->ResourceRecords; rr; rr=rr->next)
+ {
+
+ // Skip this interface if the record InterfaceID is *Any and the record is not
+ // appropriate for the interface type.
+ if ((rr->SendRNow == intf->InterfaceID) &&
+ ((rr->resrec.InterfaceID == mDNSInterface_Any) && !mDNSPlatformValidRecordForInterface(rr, intf)))
+ {
+ LogInfo("SendResponses: Not sending %s, on %s", ARDisplayString(m, rr), InterfaceNameForID(m, rr->SendRNow));
+ rr->SendRNow = GetNextActiveInterfaceID(intf);
+ }
+ else if (rr->SendRNow == intf->InterfaceID)
+ {
+ RData *OldRData = rr->resrec.rdata;
+ mDNSu16 oldrdlength = rr->resrec.rdlength;
+ mDNSu8 active = (mDNSu8)
+ (rr->resrec.RecordType != kDNSRecordTypeDeregistering && !ShouldSendGoodbyesBeforeSleep(m, intf, rr));
+ newptr = mDNSNULL;
+ if (rr->NewRData && active)
+ {
+ // See if we should send a courtesy "goodbye" for the old data before we replace it.
+ if (ResourceRecordIsValidAnswer(rr) && rr->resrec.RecordType == kDNSRecordTypeShared && rr->RequireGoodbye)
+ {
+ newptr = PutRR_OS_TTL(responseptr, &m->omsg.h.numAnswers, &rr->resrec, 0);
+ if (newptr) { responseptr = newptr; numDereg++; rr->RequireGoodbye = mDNSfalse; }
+ else continue; // If this packet is already too full to hold the goodbye for this record, skip it for now and we'll retry later
+ }
+ SetNewRData(&rr->resrec, rr->NewRData, rr->newrdlength);
+ }
+
+ if (rr->resrec.AnonInfo)
+ {
+ int tmp = AnonInfoSpace(rr->resrec.AnonInfo);
+
+ AnoninfoSpace += tmp;
+ // Adjust OwnerRecordSpace/TraceRecordSpace which is used by PutRR_OS_TTL below so that
+ // we have space to put in the NSEC3 record in the authority section.
+ OwnerRecordSpace += tmp;
+ TraceRecordSpace += tmp;
+ }
+
+ if (rr->resrec.RecordType & kDNSRecordTypeUniqueMask)
+ rr->resrec.rrclass |= kDNSClass_UniqueRRSet; // Temporarily set the cache flush bit so PutResourceRecord will set it
+ newptr = PutRR_OS_TTL(responseptr, &m->omsg.h.numAnswers, &rr->resrec, active ? rr->resrec.rroriginalttl : 0);
+ rr->resrec.rrclass &= ~kDNSClass_UniqueRRSet; // Make sure to clear cache flush bit back to normal state
+ if (newptr)
+ {
+ responseptr = newptr;
+ rr->RequireGoodbye = active;
+ if (rr->resrec.RecordType == kDNSRecordTypeDeregistering) numDereg++;
+ else if (rr->LastAPTime == m->timenow) numAnnounce++;else numAnswer++;
+ }
+
+ if (rr->NewRData && active)
+ SetNewRData(&rr->resrec, OldRData, oldrdlength);
+
+ // The first time through (pktcount==0), if this record is verified unique
+ // (i.e. typically A, AAAA, SRV, TXT and reverse-mapping PTR), set the flag to add an NSEC too.
+ if (!pktcount && active && (rr->resrec.RecordType & kDNSRecordTypeActiveUniqueMask) && !rr->SendNSECNow)
+ rr->SendNSECNow = mDNSInterfaceMark;
+
+ if (newptr) // If succeeded in sending, advance to next interface
+ {
+ if (rr->resrec.AnonInfo)
+ {
+ debugf("SendResponses: Marking %s, OwnerRecordSpace %d, TraceRecordSpace %d, limit %p", ARDisplayString(m, rr), OwnerRecordSpace,
+ TraceRecordSpace, m->omsg.data + AllowedRRSpace(&m->omsg) - OwnerRecordSpace - TraceRecordSpace);
+ rr->resrec.AnonInfo->SendNow = intf->InterfaceID;
+ }
+
+ // If sending on all interfaces, go to next interface; else we're finished now
+ if (rr->ImmedAnswer == mDNSInterfaceMark && rr->resrec.InterfaceID == mDNSInterface_Any)
+ rr->SendRNow = GetNextActiveInterfaceID(intf);
+ else
+ rr->SendRNow = mDNSNULL;
+ }
+ }
+ }
+
+ // Get the reserved space back
+ OwnerRecordSpace -= AnoninfoSpace;
+ TraceRecordSpace -= AnoninfoSpace;
+ newptr = responseptr;
+ for (rr = m->ResourceRecords; rr; rr=rr->next)
+ {
+ if (rr->resrec.AnonInfo && rr->resrec.AnonInfo->SendNow == intf->InterfaceID)
+ {
+ ResourceRecord *nsec3RR = rr->resrec.AnonInfo->nsec3RR;
+
+ newptr = PutRR_OS_TTL(newptr, &m->omsg.h.numAuthorities, nsec3RR, nsec3RR->rroriginalttl);
+ if (newptr)
+ {
+ responseptr = newptr;
+ debugf("SendResponses: Added NSEC3 %s, OwnerRecordSpace %d, TraceRecordSpace %d, limit %p", ARDisplayString(m, rr), OwnerRecordSpace,
+ TraceRecordSpace, m->omsg.data + AllowedRRSpace(&m->omsg) - OwnerRecordSpace - TraceRecordSpace);
+ }
+ else
+ {
+ LogMsg("SendResponses: Cannot add NSEC3 %s, OwnerRecordSpace %d, TraceRecordSpace %d, limit %p", ARDisplayString(m, rr), OwnerRecordSpace,
+ TraceRecordSpace, m->omsg.data + AllowedRRSpace(&m->omsg) - OwnerRecordSpace - TraceRecordSpace);
+ }
+ rr->resrec.AnonInfo->SendNow = mDNSNULL;
+ }
+ }
+ // Second Pass. Add additional records, if there's space.
+ newptr = responseptr;
+ for (rr = m->ResourceRecords; rr; rr=rr->next)
+ if (rr->ImmedAdditional == intf->InterfaceID)
+ if (ResourceRecordIsValidAnswer(rr))
+ {
+ // If we have at least one answer already in the packet, then plan to add additionals too
+ mDNSBool SendAdditional = (m->omsg.h.numAnswers > 0);
+
+ // If we're not planning to send any additionals, but this record is a unique one, then
+ // make sure we haven't already sent any other members of its RRSet -- if we have, then they
+ // will have had the cache flush bit set, so now we need to finish the job and send the rest.
+ if (!SendAdditional && (rr->resrec.RecordType & kDNSRecordTypeUniqueMask))
+ {
+ const AuthRecord *a;
+ for (a = m->ResourceRecords; a; a=a->next)
+ if (a->LastMCTime == m->timenow &&
+ a->LastMCInterface == intf->InterfaceID &&
+ SameResourceRecordSignature(a, rr)) { SendAdditional = mDNStrue; break; }
+ }
+ if (!SendAdditional) // If we don't want to send this after all,
+ rr->ImmedAdditional = mDNSNULL; // then cancel its ImmedAdditional field
+ else if (newptr) // Else, try to add it if we can
+ {
+ // The first time through (pktcount==0), if this record is verified unique
+ // (i.e. typically A, AAAA, SRV, TXT and reverse-mapping PTR), set the flag to add an NSEC too.
+ if (!pktcount && (rr->resrec.RecordType & kDNSRecordTypeActiveUniqueMask) && !rr->SendNSECNow)
+ rr->SendNSECNow = mDNSInterfaceMark;
+
+ if (rr->resrec.RecordType & kDNSRecordTypeUniqueMask)
+ rr->resrec.rrclass |= kDNSClass_UniqueRRSet; // Temporarily set the cache flush bit so PutResourceRecord will set it
+ newptr = PutRR_OS(newptr, &m->omsg.h.numAdditionals, &rr->resrec);
+ rr->resrec.rrclass &= ~kDNSClass_UniqueRRSet; // Make sure to clear cache flush bit back to normal state
+ if (newptr)
+ {
+ responseptr = newptr;
+ rr->ImmedAdditional = mDNSNULL;
+ rr->RequireGoodbye = mDNStrue;
+ // If we successfully put this additional record in the packet, we record LastMCTime & LastMCInterface.
+ // This matters particularly in the case where we have more than one IPv6 (or IPv4) address, because otherwise,
+ // when we see our own multicast with the cache flush bit set, if we haven't set LastMCTime, then we'll get
+ // all concerned and re-announce our record again to make sure it doesn't get flushed from peer caches.
+ rr->LastMCTime = m->timenow;
+ rr->LastMCInterface = intf->InterfaceID;
+ }
+ }
+ }
+
+ // Third Pass. Add NSEC records, if there's space.
+ // When we're generating an NSEC record in response to a specify query for that type
+ // (recognized by rr->SendNSECNow == intf->InterfaceID) we should really put the NSEC in the Answer Section,
+ // not Additional Section, but for now it's easier to handle both cases in this Additional Section loop here.
+ for (rr = m->ResourceRecords; rr; rr=rr->next)
+ if (rr->SendNSECNow == mDNSInterfaceMark || rr->SendNSECNow == intf->InterfaceID)
+ {
+ AuthRecord nsec;
+ mDNSu8 *ptr;
+ int len;
+ mDNS_SetupResourceRecord(&nsec, mDNSNULL, mDNSInterface_Any, kDNSType_NSEC, rr->resrec.rroriginalttl, kDNSRecordTypeUnique, AuthRecordAny, mDNSNULL, mDNSNULL);
+ nsec.resrec.rrclass |= kDNSClass_UniqueRRSet;
+ AssignDomainName(&nsec.namestorage, rr->resrec.name);
+ ptr = nsec.rdatastorage.u.data;
+ len = DomainNameLength(rr->resrec.name);
+ // We have a nxt name followed by window number, window length and a window bitmap
+ nsec.resrec.rdlength = len + 2 + NSEC_MCAST_WINDOW_SIZE;
+ if (nsec.resrec.rdlength <= StandardAuthRDSize)
+ {
+ mDNSPlatformMemZero(ptr, nsec.resrec.rdlength);
+ AssignDomainName((domainname *)ptr, rr->resrec.name);
+ ptr += len;
+ *ptr++ = 0; // window number
+ *ptr++ = NSEC_MCAST_WINDOW_SIZE; // window length
+ for (r2 = m->ResourceRecords; r2; r2=r2->next)
+ if (ResourceRecordIsValidAnswer(r2) && SameResourceRecordNameClassInterface(r2, rr))
+ {
+ if (r2->resrec.rrtype >= kDNSQType_ANY) { LogMsg("SendResponses: Can't create NSEC for record %s", ARDisplayString(m, r2)); break; }
+ else ptr[r2->resrec.rrtype >> 3] |= 128 >> (r2->resrec.rrtype & 7);
+ }
+ newptr = responseptr;
+ if (!r2) // If we successfully built our NSEC record, add it to the packet now
+ {
+ newptr = PutRR_OS(responseptr, &m->omsg.h.numAdditionals, &nsec.resrec);
+ if (newptr) responseptr = newptr;
+ }
+ }
+ else LogMsg("SendResponses: not enough space (%d) in authrecord for nsec", nsec.resrec.rdlength);
+
+ // If we successfully put the NSEC record, clear the SendNSECNow flag
+ // If we consider this NSEC optional, then we unconditionally clear the SendNSECNow flag, even if we fail to put this additional record
+ if (newptr || rr->SendNSECNow == mDNSInterfaceMark)
+ {
+ rr->SendNSECNow = mDNSNULL;
+ // Run through remainder of list clearing SendNSECNow flag for all other records which would generate the same NSEC
+ for (r2 = rr->next; r2; r2=r2->next)
+ if (SameResourceRecordNameClassInterface(r2, rr))
+ if (r2->SendNSECNow == mDNSInterfaceMark || r2->SendNSECNow == intf->InterfaceID)
+ r2->SendNSECNow = mDNSNULL;
+ }
+ }
+
+ if (m->omsg.h.numAnswers || m->omsg.h.numAdditionals)
+ {
+ // If we have data to send, add OWNER/TRACER/OWNER+TRACER option if necessary, then send packet
+ if (OwnerRecordSpace || TraceRecordSpace)
+ {
+ AuthRecord opt;
+ mDNS_SetupResourceRecord(&opt, mDNSNULL, mDNSInterface_Any, kDNSType_OPT, kStandardTTL, kDNSRecordTypeKnownUnique, AuthRecordAny, mDNSNULL, mDNSNULL);
+ opt.resrec.rrclass = NormalMaxDNSMessageData;
+ opt.resrec.rdlength = sizeof(rdataOPT);
+ opt.resrec.rdestimate = sizeof(rdataOPT);
+ if (OwnerRecordSpace && TraceRecordSpace)
+ {
+ opt.resrec.rdlength += sizeof(rdataOPT); // Two options in this OPT record
+ opt.resrec.rdestimate += sizeof(rdataOPT);
+ SetupOwnerOpt(m, intf, &opt.resrec.rdata->u.opt[0]);
+ SetupTracerOpt(m, &opt.resrec.rdata->u.opt[1]);
+ }
+ else if (OwnerRecordSpace)
+ {
+ SetupOwnerOpt(m, intf, &opt.resrec.rdata->u.opt[0]);
+ }
+ else if (TraceRecordSpace)
+ {
+ SetupTracerOpt(m, &opt.resrec.rdata->u.opt[0]);
+ }
+ newptr = PutResourceRecord(&m->omsg, responseptr, &m->omsg.h.numAdditionals, &opt.resrec);
+ if (newptr)
+ {
+ responseptr = newptr;
+ LogInfo("SendResponses put %s %s: %s %s", OwnerRecordSpace ? "OWNER" : "", TraceRecordSpace ? "TRACER" : "", intf->ifname, ARDisplayString(m, &opt));
+ }
+ else if (m->omsg.h.numAnswers + m->omsg.h.numAuthorities + m->omsg.h.numAdditionals == 1)
+ {
+ LogInfo("SendResponses: No space in packet for %s %s OPT record (%d/%d/%d/%d) %s", OwnerRecordSpace ? "OWNER" : "", TraceRecordSpace ? "TRACER" : "",
+ m->omsg.h.numQuestions, m->omsg.h.numAnswers, m->omsg.h.numAuthorities, m->omsg.h.numAdditionals, ARDisplayString(m, &opt));
+ }
+ else
+ {
+ LogMsg("SendResponses: How did we fail to have space for %s %s OPT record (%d/%d/%d/%d) %s", OwnerRecordSpace ? "OWNER" : "", TraceRecordSpace ? "TRACER" : "",
+ m->omsg.h.numQuestions, m->omsg.h.numAnswers, m->omsg.h.numAuthorities, m->omsg.h.numAdditionals, ARDisplayString(m, &opt));
+ }
+ }
+
+ debugf("SendResponses: Sending %d Deregistration%s, %d Announcement%s, %d Answer%s, %d Additional%s on %p",
+ numDereg, numDereg == 1 ? "" : "s",
+ numAnnounce, numAnnounce == 1 ? "" : "s",
+ numAnswer, numAnswer == 1 ? "" : "s",
+ m->omsg.h.numAdditionals, m->omsg.h.numAdditionals == 1 ? "" : "s", intf->InterfaceID);
+
+ if (intf->IPv4Available) mDNSSendDNSMessage(m, &m->omsg, responseptr, intf->InterfaceID, mDNSNULL, &AllDNSLinkGroup_v4, MulticastDNSPort, mDNSNULL, mDNSNULL, mDNSfalse);
+ if (intf->IPv6Available) mDNSSendDNSMessage(m, &m->omsg, responseptr, intf->InterfaceID, mDNSNULL, &AllDNSLinkGroup_v6, MulticastDNSPort, mDNSNULL, mDNSNULL, mDNSfalse);
+ if (!m->SuppressSending) m->SuppressSending = NonZeroTime(m->timenow + (mDNSPlatformOneSecond+9)/10);
+ if (++pktcount >= 1000) { LogMsg("SendResponses exceeded loop limit %d: giving up", pktcount); break; }
+ // There might be more things to send on this interface, so go around one more time and try again.
+ }
+ else // Nothing more to send on this interface; go to next
+ {
+ const NetworkInterfaceInfo *next = GetFirstActiveInterface(intf->next);
+ #if MDNS_DEBUGMSGS && 0
+ const char *const msg = next ? "SendResponses: Nothing more on %p; moving to %p" : "SendResponses: Nothing more on %p";
+ debugf(msg, intf, next);
+ #endif
+ intf = next;
+ pktcount = 0; // When we move to a new interface, reset packet count back to zero -- NSEC generation logic uses it
+ }
+ }
+
+ // ***
+ // *** 3. Cleanup: Now that everything is sent, call client callback functions, and reset state variables
+ // ***
+
+ if (m->CurrentRecord)
+ LogMsg("SendResponses ERROR m->CurrentRecord already set %s", ARDisplayString(m, m->CurrentRecord));
+ m->CurrentRecord = m->ResourceRecords;
+ while (m->CurrentRecord)
+ {
+ rr = m->CurrentRecord;
+ m->CurrentRecord = rr->next;
+
+ if (rr->SendRNow)
+ {
+ if (rr->ARType != AuthRecordLocalOnly && rr->ARType != AuthRecordP2P)
+ LogInfo("SendResponses: No active interface %d to send: %d %02X %s",
+ (uint32_t)rr->SendRNow, (uint32_t)rr->resrec.InterfaceID, rr->resrec.RecordType, ARDisplayString(m, rr));
+ rr->SendRNow = mDNSNULL;
+ }
+
+ if (rr->ImmedAnswer || rr->resrec.RecordType == kDNSRecordTypeDeregistering)
+ {
+ if (rr->NewRData) CompleteRDataUpdate(m, rr); // Update our rdata, clear the NewRData pointer, and return memory to the client
+
+ if (rr->resrec.RecordType == kDNSRecordTypeDeregistering && rr->AnnounceCount == 0)
+ {
+ // For Unicast, when we get the response from the server, we will call CompleteDeregistration
+ if (!AuthRecord_uDNS(rr)) CompleteDeregistration(m, rr); // Don't touch rr after this
+ }
+ else
+ {
+ rr->ImmedAnswer = mDNSNULL;
+ rr->ImmedUnicast = mDNSfalse;
+ rr->v4Requester = zerov4Addr;
+ rr->v6Requester = zerov6Addr;
+ }
+ }
+ }
+ verbosedebugf("SendResponses: Next in %ld ticks", m->NextScheduledResponse - m->timenow);
+}
// Calling CheckCacheExpiration() is an expensive operation because it has to look at the entire cache,
// so we want to be lazy about how frequently we do it.
// 5. For records with rroriginalttl set to zero, that means we really want to delete them immediately
// (we have a new record with DelayDelivery set, waiting for the old record to go away before we can notify clients).
#define CacheCheckGracePeriod(RR) ( \
- ((RR)->CRActiveQuestion == mDNSNULL ) ? (60 * mDNSPlatformOneSecond) : \
- ((RR)->UnansweredQueries < MaxUnansweredQueries) ? (TicksTTL(rr)/50) : \
- ((RR)->resrec.rroriginalttl > 10 ) ? (mDNSPlatformOneSecond) : \
- ((RR)->resrec.rroriginalttl > 0 ) ? (mDNSPlatformOneSecond/10) : 0)
+ ((RR)->CRActiveQuestion == mDNSNULL ) ? (60 * mDNSPlatformOneSecond) : \
+ ((RR)->UnansweredQueries < MaxUnansweredQueries) ? (TicksTTL(rr)/50) : \
+ ((RR)->resrec.rroriginalttl > 10 ) ? (mDNSPlatformOneSecond) : \
+ ((RR)->resrec.rroriginalttl > 0 ) ? (mDNSPlatformOneSecond/10) : 0)
#define NextCacheCheckEvent(RR) ((RR)->NextRequiredQuery + CacheCheckGracePeriod(RR))
mDNSexport void ScheduleNextCacheCheckTime(mDNS *const m, const mDNSu32 slot, const mDNSs32 event)
- {
- if (m->rrcache_nextcheck[slot] - event > 0)
- m->rrcache_nextcheck[slot] = event;
- if (m->NextCacheCheck - event > 0)
- m->NextCacheCheck = event;
- }
+{
+ if (m->rrcache_nextcheck[slot] - event > 0)
+ m->rrcache_nextcheck[slot] = event;
+ if (m->NextCacheCheck - event > 0)
+ m->NextCacheCheck = event;
+}
// Note: MUST call SetNextCacheCheckTimeForRecord any time we change:
// rr->TimeRcvd
// rr->resrec.rroriginalttl
// rr->UnansweredQueries
// rr->CRActiveQuestion
-mDNSlocal void SetNextCacheCheckTimeForRecord(mDNS *const m, CacheRecord *const rr)
- {
- rr->NextRequiredQuery = RRExpireTime(rr);
-
- // If we have an active question, then see if we want to schedule a refresher query for this record.
- // Usually we expect to do four queries, at 80-82%, 85-87%, 90-92% and then 95-97% of the TTL.
- if (rr->CRActiveQuestion && rr->UnansweredQueries < MaxUnansweredQueries)
- {
- rr->NextRequiredQuery -= TicksTTL(rr)/20 * (MaxUnansweredQueries - rr->UnansweredQueries);
- rr->NextRequiredQuery += mDNSRandom((mDNSu32)TicksTTL(rr)/50);
- verbosedebugf("SetNextCacheCheckTimeForRecord: NextRequiredQuery in %ld sec CacheCheckGracePeriod %d ticks for %s",
- (rr->NextRequiredQuery - m->timenow) / mDNSPlatformOneSecond, CacheCheckGracePeriod(rr), CRDisplayString(m,rr));
- }
-
- ScheduleNextCacheCheckTime(m, HashSlot(rr->resrec.name), NextCacheCheckEvent(rr));
- }
+mDNSexport void SetNextCacheCheckTimeForRecord(mDNS *const m, CacheRecord *const rr)
+{
+ rr->NextRequiredQuery = RRExpireTime(rr);
+
+ // If we have an active question, then see if we want to schedule a refresher query for this record.
+ // Usually we expect to do four queries, at 80-82%, 85-87%, 90-92% and then 95-97% of the TTL.
+ if (rr->CRActiveQuestion && rr->UnansweredQueries < MaxUnansweredQueries)
+ {
+ rr->NextRequiredQuery -= TicksTTL(rr)/20 * (MaxUnansweredQueries - rr->UnansweredQueries);
+ rr->NextRequiredQuery += mDNSRandom((mDNSu32)TicksTTL(rr)/50);
+ verbosedebugf("SetNextCacheCheckTimeForRecord: NextRequiredQuery in %ld sec CacheCheckGracePeriod %d ticks for %s",
+ (rr->NextRequiredQuery - m->timenow) / mDNSPlatformOneSecond, CacheCheckGracePeriod(rr), CRDisplayString(m,rr));
+ }
+ ScheduleNextCacheCheckTime(m, HashSlot(rr->resrec.name), NextCacheCheckEvent(rr));
+}
#define kMinimumReconfirmTime ((mDNSu32)mDNSPlatformOneSecond * 5)
#define kDefaultReconfirmTimeForWake ((mDNSu32)mDNSPlatformOneSecond * 5)
#define kDefaultReconfirmTimeForNoAnswer ((mDNSu32)mDNSPlatformOneSecond * 5)
-#define kDefaultReconfirmTimeForFlappingInterface ((mDNSu32)mDNSPlatformOneSecond * 30)
-
-mDNSlocal mStatus mDNS_Reconfirm_internal(mDNS *const m, CacheRecord *const rr, mDNSu32 interval)
- {
- if (interval < kMinimumReconfirmTime)
- interval = kMinimumReconfirmTime;
- if (interval > 0x10000000) // Make sure interval doesn't overflow when we multiply by four below
- interval = 0x10000000;
-
- // If the expected expiration time for this record is more than interval+33%, then accelerate its expiration
- if (RRExpireTime(rr) - m->timenow > (mDNSs32)((interval * 4) / 3))
- {
- // Add a 33% random amount to the interval, to avoid synchronization between multiple hosts
- // For all the reconfirmations in a given batch, we want to use the same random value
- // so that the reconfirmation questions can be grouped into a single query packet
- if (!m->RandomReconfirmDelay) m->RandomReconfirmDelay = 1 + mDNSRandom(0x3FFFFFFF);
- interval += m->RandomReconfirmDelay % ((interval/3) + 1);
- rr->TimeRcvd = m->timenow - (mDNSs32)interval * 3;
- rr->resrec.rroriginalttl = (interval * 4 + mDNSPlatformOneSecond - 1) / mDNSPlatformOneSecond;
- SetNextCacheCheckTimeForRecord(m, rr);
- }
- debugf("mDNS_Reconfirm_internal:%6ld ticks to go for %s %p",
- RRExpireTime(rr) - m->timenow, CRDisplayString(m, rr), rr->CRActiveQuestion);
- return(mStatus_NoError);
- }
-
-#define MaxQuestionInterval (3600 * mDNSPlatformOneSecond)
+#define kDefaultReconfirmTimeForFlappingInterface ((mDNSu32)mDNSPlatformOneSecond * 5)
+
+mDNSexport mStatus mDNS_Reconfirm_internal(mDNS *const m, CacheRecord *const rr, mDNSu32 interval)
+{
+ if (interval < kMinimumReconfirmTime)
+ interval = kMinimumReconfirmTime;
+ if (interval > 0x10000000) // Make sure interval doesn't overflow when we multiply by four below
+ interval = 0x10000000;
+
+ // If the expected expiration time for this record is more than interval+33%, then accelerate its expiration
+ if (RRExpireTime(rr) - m->timenow > (mDNSs32)((interval * 4) / 3))
+ {
+ // Add a 33% random amount to the interval, to avoid synchronization between multiple hosts
+ // For all the reconfirmations in a given batch, we want to use the same random value
+ // so that the reconfirmation questions can be grouped into a single query packet
+ if (!m->RandomReconfirmDelay) m->RandomReconfirmDelay = 1 + mDNSRandom(0x3FFFFFFF);
+ interval += m->RandomReconfirmDelay % ((interval/3) + 1);
+ rr->TimeRcvd = m->timenow - (mDNSs32)interval * 3;
+ rr->resrec.rroriginalttl = (interval * 4 + mDNSPlatformOneSecond - 1) / mDNSPlatformOneSecond;
+ SetNextCacheCheckTimeForRecord(m, rr);
+ }
+ debugf("mDNS_Reconfirm_internal:%6ld ticks to go for %s %p",
+ RRExpireTime(rr) - m->timenow, CRDisplayString(m, rr), rr->CRActiveQuestion);
+ return(mStatus_NoError);
+}
// BuildQuestion puts a question into a DNS Query packet and if successful, updates the value of queryptr.
// It also appends to the list of known answer records that need to be included,
// and updates the forcast for the size of the known answer section.
mDNSlocal mDNSBool BuildQuestion(mDNS *const m, DNSMessage *query, mDNSu8 **queryptr, DNSQuestion *q,
- CacheRecord ***kalistptrptr, mDNSu32 *answerforecast)
- {
- mDNSBool ucast = (q->LargeAnswers || q->RequestUnicast) && m->CanReceiveUnicastOn5353;
- mDNSu16 ucbit = (mDNSu16)(ucast ? kDNSQClass_UnicastResponse : 0);
- const mDNSu8 *const limit = query->data + NormalMaxDNSMessageData;
- mDNSu8 *newptr = putQuestion(query, *queryptr, limit - *answerforecast, &q->qname, q->qtype, (mDNSu16)(q->qclass | ucbit));
- if (!newptr)
- {
- debugf("BuildQuestion: No more space in this packet for question %##s (%s)", q->qname.c, DNSTypeName(q->qtype));
- return(mDNSfalse);
- }
- else
- {
- mDNSu32 forecast = *answerforecast;
- const mDNSu32 slot = HashSlot(&q->qname);
- const CacheGroup *const cg = CacheGroupForName(m, slot, q->qnamehash, &q->qname);
- CacheRecord *rr;
- CacheRecord **ka = *kalistptrptr; // Make a working copy of the pointer we're going to update
-
- for (rr = cg ? cg->members : mDNSNULL; rr; rr=rr->next) // If we have a resource record in our cache,
- if (rr->resrec.InterfaceID == q->SendQNow && // received on this interface
- !(rr->resrec.RecordType & kDNSRecordTypeUniqueMask) && // which is a shared (i.e. not unique) record type
- rr->NextInKAList == mDNSNULL && ka != &rr->NextInKAList && // which is not already in the known answer list
- rr->resrec.rdlength <= SmallRecordLimit && // which is small enough to sensibly fit in the packet
- SameNameRecordAnswersQuestion(&rr->resrec, q) && // which answers our question
- rr->TimeRcvd + TicksTTL(rr)/2 - m->timenow > // and its half-way-to-expiry time is at least 1 second away
- mDNSPlatformOneSecond) // (also ensures we never include goodbye records with TTL=1)
- {
- // We don't want to include unique records in the Known Answer section. The Known Answer section
- // is intended to suppress floods of shared-record replies from many other devices on the network.
- // That concept really does not apply to unique records, and indeed if we do send a query for
- // which we have a unique record already in our cache, then including that unique record as a
- // Known Answer, so as to suppress the only answer we were expecting to get, makes little sense.
-
- *ka = rr; // Link this record into our known answer chain
- ka = &rr->NextInKAList;
- // We forecast: compressed name (2) type (2) class (2) TTL (4) rdlength (2) rdata (n)
- forecast += 12 + rr->resrec.rdestimate;
- // If we're trying to put more than one question in this packet, and it doesn't fit
- // then undo that last question and try again next time
- if (query->h.numQuestions > 1 && newptr + forecast >= limit)
- {
- debugf("BuildQuestion: Retracting question %##s (%s) new forecast total %d",
- q->qname.c, DNSTypeName(q->qtype), newptr + forecast - query->data);
- query->h.numQuestions--;
- ka = *kalistptrptr; // Go back to where we started and retract these answer records
- while (*ka) { CacheRecord *c = *ka; *ka = mDNSNULL; ka = &c->NextInKAList; }
- return(mDNSfalse); // Return false, so we'll try again in the next packet
- }
- }
-
- // Success! Update our state pointers, increment UnansweredQueries as appropriate, and return
- *queryptr = newptr; // Update the packet pointer
- *answerforecast = forecast; // Update the forecast
- *kalistptrptr = ka; // Update the known answer list pointer
- if (ucast) q->ExpectUnicastResp = NonZeroTime(m->timenow);
-
- for (rr = cg ? cg->members : mDNSNULL; rr; rr=rr->next) // For every resource record in our cache,
- if (rr->resrec.InterfaceID == q->SendQNow && // received on this interface
- rr->NextInKAList == mDNSNULL && ka != &rr->NextInKAList && // which is not in the known answer list
- SameNameRecordAnswersQuestion(&rr->resrec, q)) // which answers our question
- {
- rr->UnansweredQueries++; // indicate that we're expecting a response
- rr->LastUnansweredTime = m->timenow;
- SetNextCacheCheckTimeForRecord(m, rr);
- }
-
- return(mDNStrue);
- }
- }
+ CacheRecord ***kalistptrptr, mDNSu32 *answerforecast)
+{
+ mDNSBool ucast = (q->LargeAnswers || q->RequestUnicast) && m->CanReceiveUnicastOn5353;
+ mDNSu16 ucbit = (mDNSu16)(ucast ? kDNSQClass_UnicastResponse : 0);
+ const mDNSu8 *const limit = query->data + NormalMaxDNSMessageData;
+ mDNSu8 anoninfo_space = q->AnonInfo ? AnonInfoSpace(q->AnonInfo) : 0;
+ mDNSu8 *newptr = putQuestion(query, *queryptr, limit - *answerforecast - anoninfo_space, &q->qname, q->qtype, (mDNSu16)(q->qclass | ucbit));
+ if (!newptr)
+ {
+ debugf("BuildQuestion: No more space in this packet for question %##s (%s)", q->qname.c, DNSTypeName(q->qtype));
+ return(mDNSfalse);
+ }
+ else
+ {
+ mDNSu32 forecast = *answerforecast + anoninfo_space;
+ const mDNSu32 slot = HashSlot(&q->qname);
+ const CacheGroup *const cg = CacheGroupForName(m, slot, q->qnamehash, &q->qname);
+ CacheRecord *rr;
+ CacheRecord **ka = *kalistptrptr; // Make a working copy of the pointer we're going to update
+
+ for (rr = cg ? cg->members : mDNSNULL; rr; rr=rr->next) // If we have a resource record in our cache,
+ if (rr->resrec.InterfaceID == q->SendQNow && // received on this interface
+ !(rr->resrec.RecordType & kDNSRecordTypeUniqueMask) && // which is a shared (i.e. not unique) record type
+ rr->NextInKAList == mDNSNULL && ka != &rr->NextInKAList && // which is not already in the known answer list
+ rr->resrec.rdlength <= SmallRecordLimit && // which is small enough to sensibly fit in the packet
+ SameNameRecordAnswersQuestion(&rr->resrec, q) && // which answers our question
+ rr->TimeRcvd + TicksTTL(rr)/2 - m->timenow > // and its half-way-to-expiry time is at least 1 second away
+ mDNSPlatformOneSecond) // (also ensures we never include goodbye records with TTL=1)
+ {
+ // We don't want to include unique records in the Known Answer section. The Known Answer section
+ // is intended to suppress floods of shared-record replies from many other devices on the network.
+ // That concept really does not apply to unique records, and indeed if we do send a query for
+ // which we have a unique record already in our cache, then including that unique record as a
+ // Known Answer, so as to suppress the only answer we were expecting to get, makes little sense.
+
+ *ka = rr; // Link this record into our known answer chain
+ ka = &rr->NextInKAList;
+ // We forecast: compressed name (2) type (2) class (2) TTL (4) rdlength (2) rdata (n)
+ forecast += 12 + rr->resrec.rdestimate;
+ // If we're trying to put more than one question in this packet, and it doesn't fit
+ // then undo that last question and try again next time
+ if (query->h.numQuestions > 1 && newptr + forecast >= limit)
+ {
+ query->h.numQuestions--;
+ debugf("BuildQuestion: Retracting question %##s (%s) new forecast total %d, total questions %d",
+ q->qname.c, DNSTypeName(q->qtype), newptr + forecast - query->data, query->h.numQuestions);
+ ka = *kalistptrptr; // Go back to where we started and retract these answer records
+ while (*ka) { CacheRecord *c = *ka; *ka = mDNSNULL; ka = &c->NextInKAList; }
+ return(mDNSfalse); // Return false, so we'll try again in the next packet
+ }
+ }
+
+ // Success! Update our state pointers, increment UnansweredQueries as appropriate, and return
+ *queryptr = newptr; // Update the packet pointer
+ *answerforecast = forecast; // Update the forecast
+ *kalistptrptr = ka; // Update the known answer list pointer
+ if (ucast) q->ExpectUnicastResp = NonZeroTime(m->timenow);
+
+ for (rr = cg ? cg->members : mDNSNULL; rr; rr=rr->next) // For every resource record in our cache,
+ if (rr->resrec.InterfaceID == q->SendQNow && // received on this interface
+ rr->NextInKAList == mDNSNULL && ka != &rr->NextInKAList && // which is not in the known answer list
+ SameNameRecordAnswersQuestion(&rr->resrec, q)) // which answers our question
+ {
+ rr->UnansweredQueries++; // indicate that we're expecting a response
+ rr->LastUnansweredTime = m->timenow;
+ SetNextCacheCheckTimeForRecord(m, rr);
+ }
+
+ return(mDNStrue);
+ }
+}
// When we have a query looking for a specified name, but there appear to be no answers with
// that name, ReconfirmAntecedents() is called with depth=0 to start the reconfirmation process
// Currently depths 4 and 5 are not expected to occur; if we did get to depth 5 we'd reconfim any records we
// found referring to the given name, but not recursively descend any further reconfirm *their* antecedents.
mDNSlocal void ReconfirmAntecedents(mDNS *const m, const domainname *const name, const mDNSu32 namehash, const int depth)
- {
- mDNSu32 slot;
- CacheGroup *cg;
- CacheRecord *cr;
- debugf("ReconfirmAntecedents (depth=%d) for %##s", depth, name->c);
- FORALL_CACHERECORDS(slot, cg, cr)
- {
- domainname *crtarget = GetRRDomainNameTarget(&cr->resrec);
- if (crtarget && cr->resrec.rdatahash == namehash && SameDomainName(crtarget, name))
- {
- LogInfo("ReconfirmAntecedents: Reconfirming (depth=%d) %s", depth, CRDisplayString(m, cr));
- mDNS_Reconfirm_internal(m, cr, kDefaultReconfirmTimeForNoAnswer);
- if (depth < 5) ReconfirmAntecedents(m, cr->resrec.name, cr->resrec.namehash, depth+1);
- }
- }
- }
+{
+ mDNSu32 slot;
+ CacheGroup *cg;
+ CacheRecord *cr;
+ debugf("ReconfirmAntecedents (depth=%d) for %##s", depth, name->c);
+ FORALL_CACHERECORDS(slot, cg, cr)
+ {
+ domainname *crtarget = GetRRDomainNameTarget(&cr->resrec);
+ if (crtarget && cr->resrec.rdatahash == namehash && SameDomainName(crtarget, name))
+ {
+ LogInfo("ReconfirmAntecedents: Reconfirming (depth=%d) %s", depth, CRDisplayString(m, cr));
+ mDNS_Reconfirm_internal(m, cr, kDefaultReconfirmTimeForNoAnswer);
+ if (depth < 5)
+ ReconfirmAntecedents(m, cr->resrec.name, cr->resrec.namehash, depth+1);
+ }
+ }
+}
// If we get no answer for a AAAA query, then before doing an automatic implicit ReconfirmAntecedents
// we check if we have an address record for the same name. If we do have an IPv4 address for a given
// name but not an IPv6 address, that's okay (it just means the device doesn't do IPv6) so the failure
// to get a AAAA response is not grounds to doubt the PTR/SRV chain that lead us to that name.
mDNSlocal const CacheRecord *CacheHasAddressTypeForName(mDNS *const m, const domainname *const name, const mDNSu32 namehash)
- {
- CacheGroup *const cg = CacheGroupForName(m, HashSlot(name), namehash, name);
- const CacheRecord *cr = cg ? cg->members : mDNSNULL;
- while (cr && !RRTypeIsAddressType(cr->resrec.rrtype)) cr=cr->next;
- return(cr);
- }
+{
+ CacheGroup *const cg = CacheGroupForName(m, HashSlot(name), namehash, name);
+ const CacheRecord *cr = cg ? cg->members : mDNSNULL;
+ while (cr && !RRTypeIsAddressType(cr->resrec.rrtype)) cr=cr->next;
+ return(cr);
+}
+
mDNSlocal const CacheRecord *FindSPSInCache1(mDNS *const m, const DNSQuestion *const q, const CacheRecord *const c0, const CacheRecord *const c1)
- {
- CacheGroup *const cg = CacheGroupForName(m, HashSlot(&q->qname), q->qnamehash, &q->qname);
- const CacheRecord *cr, *bestcr = mDNSNULL;
- mDNSu32 bestmetric = 1000000;
- for (cr = cg ? cg->members : mDNSNULL; cr; cr=cr->next)
- if (cr->resrec.rrtype == kDNSType_PTR && cr->resrec.rdlength >= 6) // If record is PTR type, with long enough name,
- if (cr != c0 && cr != c1) // that's not one we've seen before,
- if (SameNameRecordAnswersQuestion(&cr->resrec, q)) // and answers our browse query,
- if (!IdenticalSameNameRecord(&cr->resrec, &m->SPSRecords.RR_PTR.resrec)) // and is not our own advertised service...
- {
- mDNSu32 metric = SPSMetric(cr->resrec.rdata->u.name.c);
- if (bestmetric > metric) { bestmetric = metric; bestcr = cr; }
- }
- return(bestcr);
- }
+{
+#ifndef SPC_DISABLED
+ CacheGroup *const cg = CacheGroupForName(m, HashSlot(&q->qname), q->qnamehash, &q->qname);
+ const CacheRecord *cr, *bestcr = mDNSNULL;
+ mDNSu32 bestmetric = 1000000;
+ for (cr = cg ? cg->members : mDNSNULL; cr; cr=cr->next)
+ if (cr->resrec.rrtype == kDNSType_PTR && cr->resrec.rdlength >= 6) // If record is PTR type, with long enough name,
+ if (cr != c0 && cr != c1) // that's not one we've seen before,
+ if (SameNameRecordAnswersQuestion(&cr->resrec, q)) // and answers our browse query,
+ if (!IdenticalSameNameRecord(&cr->resrec, &m->SPSRecords.RR_PTR.resrec)) // and is not our own advertised service...
+ {
+ mDNSu32 metric = SPSMetric(cr->resrec.rdata->u.name.c);
+ if (bestmetric > metric) { bestmetric = metric; bestcr = cr; }
+ }
+ return(bestcr);
+#else // SPC_DISABLED
+ (void) m;
+ (void) q;
+ (void) c0;
+ (void) c1;
+ (void) c1;
+ return mDNSNULL;
+#endif // SPC_DISABLED
+}
+
+mDNSlocal void CheckAndSwapSPS(const CacheRecord *sps1, const CacheRecord *sps2)
+{
+ const CacheRecord *swap_sps;
+ mDNSu32 metric1, metric2;
+
+ if (!sps1 || !sps2) return;
+ metric1 = SPSMetric(sps1->resrec.rdata->u.name.c);
+ metric2 = SPSMetric(sps2->resrec.rdata->u.name.c);
+ if (!SPSFeatures(sps1->resrec.rdata->u.name.c) && SPSFeatures(sps2->resrec.rdata->u.name.c) && (metric2 >= metric1))
+ {
+ swap_sps = sps1;
+ sps1 = sps2;
+ sps2 = swap_sps;
+ }
+}
+
+mDNSlocal void ReorderSPSByFeature(const CacheRecord *sps[3])
+{
+ CheckAndSwapSPS(sps[0], sps[1]);
+ CheckAndSwapSPS(sps[0], sps[2]);
+ CheckAndSwapSPS(sps[1], sps[2]);
+}
+
// Finds the three best Sleep Proxies we currently have in our cache
mDNSexport void FindSPSInCache(mDNS *const m, const DNSQuestion *const q, const CacheRecord *sps[3])
- {
- sps[0] = FindSPSInCache1(m, q, mDNSNULL, mDNSNULL);
- sps[1] = !sps[0] ? mDNSNULL : FindSPSInCache1(m, q, sps[0], mDNSNULL);
- sps[2] = !sps[1] ? mDNSNULL : FindSPSInCache1(m, q, sps[0], sps[1]);
- }
+{
+ sps[0] = FindSPSInCache1(m, q, mDNSNULL, mDNSNULL);
+ sps[1] = !sps[0] ? mDNSNULL : FindSPSInCache1(m, q, sps[0], mDNSNULL);
+ sps[2] = !sps[1] ? mDNSNULL : FindSPSInCache1(m, q, sps[0], sps[1]);
+
+ // SPS is already sorted by metric. We want to move the entries to the beginning of the array
+ // only if they have equally good metric and support features.
+ ReorderSPSByFeature(sps);
+}
// Only DupSuppressInfos newer than the specified 'time' are allowed to remain active
mDNSlocal void ExpireDupSuppressInfo(DupSuppressInfo ds[DupSuppressInfoSize], mDNSs32 time)
- {
- int i;
- for (i=0; i<DupSuppressInfoSize; i++) if (ds[i].Time - time < 0) ds[i].InterfaceID = mDNSNULL;
- }
+{
+ int i;
+ for (i=0; i<DupSuppressInfoSize; i++) if (ds[i].Time - time < 0) ds[i].InterfaceID = mDNSNULL;
+}
mDNSlocal void ExpireDupSuppressInfoOnInterface(DupSuppressInfo ds[DupSuppressInfoSize], mDNSs32 time, mDNSInterfaceID InterfaceID)
- {
- int i;
- for (i=0; i<DupSuppressInfoSize; i++) if (ds[i].InterfaceID == InterfaceID && ds[i].Time - time < 0) ds[i].InterfaceID = mDNSNULL;
- }
+{
+ int i;
+ for (i=0; i<DupSuppressInfoSize; i++) if (ds[i].InterfaceID == InterfaceID && ds[i].Time - time < 0) ds[i].InterfaceID = mDNSNULL;
+}
mDNSlocal mDNSBool SuppressOnThisInterface(const DupSuppressInfo ds[DupSuppressInfoSize], const NetworkInterfaceInfo * const intf)
- {
- int i;
- mDNSBool v4 = !intf->IPv4Available; // If this interface doesn't do v4, we don't need to find a v4 duplicate of this query
- mDNSBool v6 = !intf->IPv6Available; // If this interface doesn't do v6, we don't need to find a v6 duplicate of this query
- for (i=0; i<DupSuppressInfoSize; i++)
- if (ds[i].InterfaceID == intf->InterfaceID)
- {
- if (ds[i].Type == mDNSAddrType_IPv4) v4 = mDNStrue;
- else if (ds[i].Type == mDNSAddrType_IPv6) v6 = mDNStrue;
- if (v4 && v6) return(mDNStrue);
- }
- return(mDNSfalse);
- }
+{
+ int i;
+ mDNSBool v4 = !intf->IPv4Available; // If this interface doesn't do v4, we don't need to find a v4 duplicate of this query
+ mDNSBool v6 = !intf->IPv6Available; // If this interface doesn't do v6, we don't need to find a v6 duplicate of this query
+ for (i=0; i<DupSuppressInfoSize; i++)
+ if (ds[i].InterfaceID == intf->InterfaceID)
+ {
+ if (ds[i].Type == mDNSAddrType_IPv4) v4 = mDNStrue;
+ else if (ds[i].Type == mDNSAddrType_IPv6) v6 = mDNStrue;
+ if (v4 && v6) return(mDNStrue);
+ }
+ return(mDNSfalse);
+}
mDNSlocal int RecordDupSuppressInfo(DupSuppressInfo ds[DupSuppressInfoSize], mDNSs32 Time, mDNSInterfaceID InterfaceID, mDNSs32 Type)
- {
- int i, j;
-
- // See if we have this one in our list somewhere already
- for (i=0; i<DupSuppressInfoSize; i++) if (ds[i].InterfaceID == InterfaceID && ds[i].Type == Type) break;
-
- // If not, find a slot we can re-use
- if (i >= DupSuppressInfoSize)
- {
- i = 0;
- for (j=1; j<DupSuppressInfoSize && ds[i].InterfaceID; j++)
- if (!ds[j].InterfaceID || ds[j].Time - ds[i].Time < 0)
- i = j;
- }
-
- // Record the info about this query we saw
- ds[i].Time = Time;
- ds[i].InterfaceID = InterfaceID;
- ds[i].Type = Type;
-
- return(i);
- }
+{
+ int i, j;
+
+ // See if we have this one in our list somewhere already
+ for (i=0; i<DupSuppressInfoSize; i++) if (ds[i].InterfaceID == InterfaceID && ds[i].Type == Type) break;
+
+ // If not, find a slot we can re-use
+ if (i >= DupSuppressInfoSize)
+ {
+ i = 0;
+ for (j=1; j<DupSuppressInfoSize && ds[i].InterfaceID; j++)
+ if (!ds[j].InterfaceID || ds[j].Time - ds[i].Time < 0)
+ i = j;
+ }
+
+ // Record the info about this query we saw
+ ds[i].Time = Time;
+ ds[i].InterfaceID = InterfaceID;
+ ds[i].Type = Type;
+
+ return(i);
+}
mDNSlocal void mDNSSendWakeOnResolve(mDNS *const m, DNSQuestion *q)
- {
- int len, i, cnt;
- mDNSInterfaceID InterfaceID = q->InterfaceID;
- domainname *d = &q->qname;
-
- // We can't send magic packets without knowing which interface to send it on.
- if (InterfaceID == mDNSInterface_Any || InterfaceID == mDNSInterface_LocalOnly || InterfaceID == mDNSInterface_P2P)
- {
- LogMsg("mDNSSendWakeOnResolve: ERROR!! Invalid InterfaceID %p for question %##s", InterfaceID, q->qname.c);
- return;
- }
-
- // Split MAC@IPAddress and pass them separately
- len = d->c[0];
- i = 1;
- cnt = 0;
- for (i = 1; i < len; i++)
- {
- if (d->c[i] == '@')
- {
- char EthAddr[18]; // ethernet adddress : 12 bytes + 5 ":" + 1 NULL byte
- char IPAddr[47]; // Max IP address len: 46 bytes (IPv6) + 1 NULL byte
- if (cnt != 5)
- {
- LogMsg("mDNSSendWakeOnResolve: ERROR!! Malformed Ethernet address %##s, cnt %d", q->qname.c, cnt);
- return;
- }
- if ((i - 1) > (int) (sizeof(EthAddr) - 1))
- {
- LogMsg("mDNSSendWakeOnResolve: ERROR!! Malformed Ethernet address %##s, length %d", q->qname.c, i - 1);
- return;
- }
- if ((len - i) > (int)(sizeof(IPAddr) - 1))
- {
- LogMsg("mDNSSendWakeOnResolve: ERROR!! Malformed IP address %##s, length %d", q->qname.c, len - i);
- return;
- }
- mDNSPlatformMemCopy(EthAddr, &d->c[1], i - 1);
- EthAddr[i - 1] = 0;
- mDNSPlatformMemCopy(IPAddr, &d->c[i + 1], len - i);
- IPAddr[len - i] = 0;
- mDNSPlatformSendWakeupPacket(m, InterfaceID, EthAddr, IPAddr, InitialWakeOnResolveCount - q->WakeOnResolveCount);
- return;
- }
- else if (d->c[i] == ':')
- cnt++;
- }
- LogMsg("mDNSSendWakeOnResolve: ERROR!! Malformed WakeOnResolve name %##s", q->qname.c);
- }
-
+{
+ int len, i, cnt;
+ mDNSInterfaceID InterfaceID = q->InterfaceID;
+ domainname *d = &q->qname;
+
+ // We can't send magic packets without knowing which interface to send it on.
+ if (InterfaceID == mDNSInterface_Any || InterfaceID == mDNSInterface_LocalOnly || InterfaceID == mDNSInterface_P2P)
+ {
+ LogMsg("mDNSSendWakeOnResolve: ERROR!! Invalid InterfaceID %p for question %##s", InterfaceID, q->qname.c);
+ return;
+ }
+
+ // Split MAC@IPAddress and pass them separately
+ len = d->c[0];
+ i = 1;
+ cnt = 0;
+ for (i = 1; i < len; i++)
+ {
+ if (d->c[i] == '@')
+ {
+ char EthAddr[18]; // ethernet adddress : 12 bytes + 5 ":" + 1 NULL byte
+ char IPAddr[47]; // Max IP address len: 46 bytes (IPv6) + 1 NULL byte
+ if (cnt != 5)
+ {
+ LogMsg("mDNSSendWakeOnResolve: ERROR!! Malformed Ethernet address %##s, cnt %d", q->qname.c, cnt);
+ return;
+ }
+ if ((i - 1) > (int) (sizeof(EthAddr) - 1))
+ {
+ LogMsg("mDNSSendWakeOnResolve: ERROR!! Malformed Ethernet address %##s, length %d", q->qname.c, i - 1);
+ return;
+ }
+ if ((len - i) > (int)(sizeof(IPAddr) - 1))
+ {
+ LogMsg("mDNSSendWakeOnResolve: ERROR!! Malformed IP address %##s, length %d", q->qname.c, len - i);
+ return;
+ }
+ mDNSPlatformMemCopy(EthAddr, &d->c[1], i - 1);
+ EthAddr[i - 1] = 0;
+ mDNSPlatformMemCopy(IPAddr, &d->c[i + 1], len - i);
+ IPAddr[len - i] = 0;
+ m->mDNSStats.WakeOnResolves++;
+ mDNSPlatformSendWakeupPacket(m, InterfaceID, EthAddr, IPAddr, InitialWakeOnResolveCount - q->WakeOnResolveCount);
+ return;
+ }
+ else if (d->c[i] == ':')
+ cnt++;
+ }
+ LogMsg("mDNSSendWakeOnResolve: ERROR!! Malformed WakeOnResolve name %##s", q->qname.c);
+}
+
mDNSlocal mDNSBool AccelerateThisQuery(mDNS *const m, DNSQuestion *q)
- {
- // If more than 90% of the way to the query time, we should unconditionally accelerate it
- if (TimeToSendThisQuestion(q, m->timenow + q->ThisQInterval/10))
- return(mDNStrue);
-
- // If half-way to next scheduled query time, only accelerate if it will add less than 512 bytes to the packet
- if (TimeToSendThisQuestion(q, m->timenow + q->ThisQInterval/2))
- {
- // We forecast: qname (n) type (2) class (2)
- mDNSu32 forecast = (mDNSu32)DomainNameLength(&q->qname) + 4;
- const mDNSu32 slot = HashSlot(&q->qname);
- const CacheGroup *const cg = CacheGroupForName(m, slot, q->qnamehash, &q->qname);
- const CacheRecord *rr;
- for (rr = cg ? cg->members : mDNSNULL; rr; rr=rr->next) // If we have a resource record in our cache,
- if (rr->resrec.rdlength <= SmallRecordLimit && // which is small enough to sensibly fit in the packet
- SameNameRecordAnswersQuestion(&rr->resrec, q) && // which answers our question
- rr->TimeRcvd + TicksTTL(rr)/2 - m->timenow >= 0 && // and it is less than half-way to expiry
- rr->NextRequiredQuery - (m->timenow + q->ThisQInterval) > 0)// and we'll ask at least once again before NextRequiredQuery
- {
- // We forecast: compressed name (2) type (2) class (2) TTL (4) rdlength (2) rdata (n)
- forecast += 12 + rr->resrec.rdestimate;
- if (forecast >= 512) return(mDNSfalse); // If this would add 512 bytes or more to the packet, don't accelerate
- }
- return(mDNStrue);
- }
-
- return(mDNSfalse);
- }
+{
+ // If more than 90% of the way to the query time, we should unconditionally accelerate it
+ if (TimeToSendThisQuestion(q, m->timenow + q->ThisQInterval/10))
+ return(mDNStrue);
+
+ // If half-way to next scheduled query time, only accelerate if it will add less than 512 bytes to the packet
+ if (TimeToSendThisQuestion(q, m->timenow + q->ThisQInterval/2))
+ {
+ // We forecast: qname (n) type (2) class (2)
+ mDNSu32 forecast = (mDNSu32)DomainNameLength(&q->qname) + 4;
+ const mDNSu32 slot = HashSlot(&q->qname);
+ const CacheGroup *const cg = CacheGroupForName(m, slot, q->qnamehash, &q->qname);
+ const CacheRecord *rr;
+ for (rr = cg ? cg->members : mDNSNULL; rr; rr=rr->next) // If we have a resource record in our cache,
+ if (rr->resrec.rdlength <= SmallRecordLimit && // which is small enough to sensibly fit in the packet
+ SameNameRecordAnswersQuestion(&rr->resrec, q) && // which answers our question
+ rr->TimeRcvd + TicksTTL(rr)/2 - m->timenow >= 0 && // and it is less than half-way to expiry
+ rr->NextRequiredQuery - (m->timenow + q->ThisQInterval) > 0) // and we'll ask at least once again before NextRequiredQuery
+ {
+ // We forecast: compressed name (2) type (2) class (2) TTL (4) rdlength (2) rdata (n)
+ forecast += 12 + rr->resrec.rdestimate;
+ if (forecast >= 512) return(mDNSfalse); // If this would add 512 bytes or more to the packet, don't accelerate
+ }
+ return(mDNStrue);
+ }
+
+ return(mDNSfalse);
+}
// How Standard Queries are generated:
// 1. The Question Section contains the question
// planning, in order to apply the tie-breaking rule to see who gets to use the name and who doesn't.
mDNSlocal void SendQueries(mDNS *const m)
- {
- mDNSu32 slot;
- CacheGroup *cg;
- CacheRecord *cr;
- AuthRecord *ar;
- int pktcount = 0;
- DNSQuestion *q;
- // For explanation of maxExistingQuestionInterval logic, see comments for maxExistingAnnounceInterval
- mDNSs32 maxExistingQuestionInterval = 0;
- const NetworkInterfaceInfo *intf = GetFirstActiveInterface(m->HostInterfaces);
- CacheRecord *KnownAnswerList = mDNSNULL;
-
- // 1. If time for a query, work out what we need to do
-
- // We're expecting to send a query anyway, so see if any expiring cache records are close enough
- // to their NextRequiredQuery to be worth batching them together with this one
- FORALL_CACHERECORDS(slot, cg, cr)
- if (cr->CRActiveQuestion && cr->UnansweredQueries < MaxUnansweredQueries)
- if (m->timenow + TicksTTL(cr)/50 - cr->NextRequiredQuery >= 0)
- {
- debugf("Sending %d%% cache expiration query for %s", 80 + 5 * cr->UnansweredQueries, CRDisplayString(m, cr));
- q = cr->CRActiveQuestion;
- ExpireDupSuppressInfoOnInterface(q->DupSuppress, m->timenow - TicksTTL(cr)/20, cr->resrec.InterfaceID);
- // For uDNS queries (TargetQID non-zero) we adjust LastQTime,
- // and bump UnansweredQueries so that we don't spin trying to send the same cache expiration query repeatedly
- if (q->Target.type) q->SendQNow = mDNSInterfaceMark; // If targeted query, mark it
- else if (!mDNSOpaque16IsZero(q->TargetQID)) { q->LastQTime = m->timenow - q->ThisQInterval; cr->UnansweredQueries++; }
- else if (q->SendQNow == mDNSNULL) q->SendQNow = cr->resrec.InterfaceID;
- else if (q->SendQNow != cr->resrec.InterfaceID) q->SendQNow = mDNSInterfaceMark;
- }
-
- // Scan our list of questions to see which:
- // *WideArea* queries need to be sent
- // *unicast* queries need to be sent
- // *multicast* queries we're definitely going to send
- if (m->CurrentQuestion)
- LogMsg("SendQueries ERROR m->CurrentQuestion already set: %##s (%s)", m->CurrentQuestion->qname.c, DNSTypeName(m->CurrentQuestion->qtype));
- m->CurrentQuestion = m->Questions;
- while (m->CurrentQuestion && m->CurrentQuestion != m->NewQuestions)
- {
- q = m->CurrentQuestion;
- if (q->Target.type && (q->SendQNow || TimeToSendThisQuestion(q, m->timenow)))
- {
- mDNSu8 *qptr = m->omsg.data;
- const mDNSu8 *const limit = m->omsg.data + sizeof(m->omsg.data);
-
- // If we fail to get a new on-demand socket (should only happen cases of the most extreme resource exhaustion), we'll try again next time
- if (!q->LocalSocket) q->LocalSocket = mDNSPlatformUDPSocket(m, zeroIPPort);
- if (q->LocalSocket)
- {
- InitializeDNSMessage(&m->omsg.h, q->TargetQID, QueryFlags);
- qptr = putQuestion(&m->omsg, qptr, limit, &q->qname, q->qtype, q->qclass);
- mDNSSendDNSMessage(m, &m->omsg, qptr, mDNSInterface_Any, q->LocalSocket, &q->Target, q->TargetPort, mDNSNULL, mDNSNULL);
- q->ThisQInterval *= QuestionIntervalStep;
- }
- if (q->ThisQInterval > MaxQuestionInterval)
- q->ThisQInterval = MaxQuestionInterval;
- q->LastQTime = m->timenow;
- q->LastQTxTime = m->timenow;
- q->RecentAnswerPkts = 0;
- q->SendQNow = mDNSNULL;
- q->ExpectUnicastResp = NonZeroTime(m->timenow);
- }
- else if (mDNSOpaque16IsZero(q->TargetQID) && !q->Target.type && TimeToSendThisQuestion(q, m->timenow))
- {
- //LogInfo("Time to send %##s (%s) %d", q->qname.c, DNSTypeName(q->qtype), m->timenow - NextQSendTime(q));
- q->SendQNow = mDNSInterfaceMark; // Mark this question for sending on all interfaces
- if (maxExistingQuestionInterval < q->ThisQInterval)
- maxExistingQuestionInterval = q->ThisQInterval;
- }
- // If m->CurrentQuestion wasn't modified out from under us, advance it now
- // We can't do this at the start of the loop because uDNS_CheckCurrentQuestion() depends on having
- // m->CurrentQuestion point to the right question
- if (q == m->CurrentQuestion) m->CurrentQuestion = m->CurrentQuestion->next;
- }
- while (m->CurrentQuestion)
- {
- LogInfo("SendQueries question loop 1: Skipping NewQuestion %##s (%s)", m->CurrentQuestion->qname.c, DNSTypeName(m->CurrentQuestion->qtype));
- m->CurrentQuestion = m->CurrentQuestion->next;
- }
- m->CurrentQuestion = mDNSNULL;
-
- // Scan our list of questions
- // (a) to see if there are any more that are worth accelerating, and
- // (b) to update the state variables for *all* the questions we're going to send
- // Note: Don't set NextScheduledQuery until here, because uDNS_CheckCurrentQuestion in the loop above can add new questions to the list,
- // which causes NextScheduledQuery to get (incorrectly) set to m->timenow. Setting it here is the right place, because the very
- // next thing we do is scan the list and call SetNextQueryTime() for every question we find, so we know we end up with the right value.
- m->NextScheduledQuery = m->timenow + 0x78000000;
- for (q = m->Questions; q && q != m->NewQuestions; q=q->next)
- {
- if (mDNSOpaque16IsZero(q->TargetQID) && (q->SendQNow ||
- (!q->Target.type && ActiveQuestion(q) && q->ThisQInterval <= maxExistingQuestionInterval && AccelerateThisQuery(m,q))))
- {
- // If at least halfway to next query time, advance to next interval
- // If less than halfway to next query time, then
- // treat this as logically a repeat of the last transmission, without advancing the interval
- if (m->timenow - (q->LastQTime + (q->ThisQInterval/2)) >= 0)
- {
- //LogInfo("Accelerating %##s (%s) %d", q->qname.c, DNSTypeName(q->qtype), m->timenow - NextQSendTime(q));
- q->SendQNow = mDNSInterfaceMark; // Mark this question for sending on all interfaces
- debugf("SendQueries: %##s (%s) next interval %d seconds RequestUnicast = %d",
- q->qname.c, DNSTypeName(q->qtype), q->ThisQInterval / InitialQuestionInterval, q->RequestUnicast);
- q->ThisQInterval *= QuestionIntervalStep;
- if (q->ThisQInterval > MaxQuestionInterval)
- q->ThisQInterval = MaxQuestionInterval;
- else if (q->CurrentAnswers == 0 && q->ThisQInterval == InitialQuestionInterval * QuestionIntervalStep3 && !q->RequestUnicast &&
- !(RRTypeIsAddressType(q->qtype) && CacheHasAddressTypeForName(m, &q->qname, q->qnamehash)))
- {
- // Generally don't need to log this.
- // It's not especially noteworthy if a query finds no results -- this usually happens for domain
- // enumeration queries in the LL subdomain (e.g. "db._dns-sd._udp.0.0.254.169.in-addr.arpa")
- // and when there simply happen to be no instances of the service the client is looking
- // for (e.g. iTunes is set to look for RAOP devices, and the current network has none).
- debugf("SendQueries: Zero current answers for %##s (%s); will reconfirm antecedents",
- q->qname.c, DNSTypeName(q->qtype));
- // Sending third query, and no answers yet; time to begin doubting the source
- ReconfirmAntecedents(m, &q->qname, q->qnamehash, 0);
- }
- }
-
- // Mark for sending. (If no active interfaces, then don't even try.)
- q->SendOnAll = (q->SendQNow == mDNSInterfaceMark);
- if (q->SendOnAll)
- {
- q->SendQNow = !intf ? mDNSNULL : (q->InterfaceID) ? q->InterfaceID : intf->InterfaceID;
- q->LastQTime = m->timenow;
- }
-
- // If we recorded a duplicate suppression for this question less than half an interval ago,
- // then we consider it recent enough that we don't need to do an identical query ourselves.
- ExpireDupSuppressInfo(q->DupSuppress, m->timenow - q->ThisQInterval/2);
-
- q->LastQTxTime = m->timenow;
- q->RecentAnswerPkts = 0;
- if (q->RequestUnicast) q->RequestUnicast--;
- }
- // For all questions (not just the ones we're sending) check what the next scheduled event will be
- // We don't need to consider NewQuestions here because for those we'll set m->NextScheduledQuery in AnswerNewQuestion
- SetNextQueryTime(m,q);
- }
-
- // 2. Scan our authoritative RR list to see what probes we might need to send
-
- m->NextScheduledProbe = m->timenow + 0x78000000;
-
- if (m->CurrentRecord)
- LogMsg("SendQueries ERROR m->CurrentRecord already set %s", ARDisplayString(m, m->CurrentRecord));
- m->CurrentRecord = m->ResourceRecords;
- while (m->CurrentRecord)
- {
- ar = m->CurrentRecord;
- m->CurrentRecord = ar->next;
- if (!AuthRecord_uDNS(ar) && ar->resrec.RecordType == kDNSRecordTypeUnique) // For all records that are still probing...
- {
- // 1. If it's not reached its probe time, just make sure we update m->NextScheduledProbe correctly
- if (m->timenow - (ar->LastAPTime + ar->ThisAPInterval) < 0)
- {
- SetNextAnnounceProbeTime(m, ar);
- }
- // 2. else, if it has reached its probe time, mark it for sending and then update m->NextScheduledProbe correctly
- else if (ar->ProbeCount)
- {
- if (ar->AddressProxy.type == mDNSAddrType_IPv4)
- {
- LogSPS("SendQueries ARP Probe %d %s %s", ar->ProbeCount, InterfaceNameForID(m, ar->resrec.InterfaceID), ARDisplayString(m,ar));
- SendARP(m, 1, ar, &zerov4Addr, &zeroEthAddr, &ar->AddressProxy.ip.v4, &ar->WakeUp.IMAC);
- }
- else if (ar->AddressProxy.type == mDNSAddrType_IPv6)
- {
- LogSPS("SendQueries NDP Probe %d %s %s", ar->ProbeCount, InterfaceNameForID(m, ar->resrec.InterfaceID), ARDisplayString(m,ar));
- // IPv6 source = zero
- // No target hardware address
- // IPv6 target address is address we're probing
- // Ethernet destination address is Ethernet interface address of the Sleep Proxy client we're probing
- SendNDP(m, NDP_Sol, 0, ar, &zerov6Addr, mDNSNULL, &ar->AddressProxy.ip.v6, &ar->WakeUp.IMAC);
- }
- // Mark for sending. (If no active interfaces, then don't even try.)
- ar->SendRNow = (!intf || ar->WakeUp.HMAC.l[0]) ? mDNSNULL : ar->resrec.InterfaceID ? ar->resrec.InterfaceID : intf->InterfaceID;
- ar->LastAPTime = m->timenow;
- // When we have a late conflict that resets a record to probing state we use a special marker value greater
- // than DefaultProbeCountForTypeUnique. Here we detect that state and reset ar->ProbeCount back to the right value.
- if (ar->ProbeCount > DefaultProbeCountForTypeUnique)
- ar->ProbeCount = DefaultProbeCountForTypeUnique;
- ar->ProbeCount--;
- SetNextAnnounceProbeTime(m, ar);
- if (ar->ProbeCount == 0)
- {
- // If this is the last probe for this record, then see if we have any matching records
- // on our duplicate list which should similarly have their ProbeCount cleared to zero...
- AuthRecord *r2;
- for (r2 = m->DuplicateRecords; r2; r2=r2->next)
- if (r2->resrec.RecordType == kDNSRecordTypeUnique && RecordIsLocalDuplicate(r2, ar))
- r2->ProbeCount = 0;
- // ... then acknowledge this record to the client.
- // We do this optimistically, just as we're about to send the third probe.
- // This helps clients that both advertise and browse, and want to filter themselves
- // from the browse results list, because it helps ensure that the registration
- // confirmation will be delivered 1/4 second *before* the browse "add" event.
- // A potential downside is that we could deliver a registration confirmation and then find out
- // moments later that there's a name conflict, but applications have to be prepared to handle
- // late conflicts anyway (e.g. on connection of network cable, etc.), so this is nothing new.
- if (!ar->Acknowledged) AcknowledgeRecord(m, ar);
- }
- }
- // else, if it has now finished probing, move it to state Verified,
- // and update m->NextScheduledResponse so it will be announced
- else
- {
- if (!ar->Acknowledged) AcknowledgeRecord(m, ar); // Defensive, just in case it got missed somehow
- ar->resrec.RecordType = kDNSRecordTypeVerified;
- ar->ThisAPInterval = DefaultAnnounceIntervalForTypeUnique;
- ar->LastAPTime = m->timenow - DefaultAnnounceIntervalForTypeUnique;
- SetNextAnnounceProbeTime(m, ar);
- }
- }
- }
- m->CurrentRecord = m->DuplicateRecords;
- while (m->CurrentRecord)
- {
- ar = m->CurrentRecord;
- m->CurrentRecord = ar->next;
- if (ar->resrec.RecordType == kDNSRecordTypeUnique && ar->ProbeCount == 0 && !ar->Acknowledged)
- AcknowledgeRecord(m, ar);
- }
-
- // 3. Now we know which queries and probes we're sending,
- // go through our interface list sending the appropriate queries on each interface
- while (intf)
- {
- const int OwnerRecordSpace = (m->AnnounceOwner && intf->MAC.l[0]) ? DNSOpt_Header_Space + DNSOpt_Owner_Space(&m->PrimaryMAC, &intf->MAC) : 0;
- mDNSu8 *queryptr = m->omsg.data;
- InitializeDNSMessage(&m->omsg.h, zeroID, QueryFlags);
- if (KnownAnswerList) verbosedebugf("SendQueries: KnownAnswerList set... Will continue from previous packet");
- if (!KnownAnswerList)
- {
- // Start a new known-answer list
- CacheRecord **kalistptr = &KnownAnswerList;
- mDNSu32 answerforecast = OwnerRecordSpace; // We start by assuming we'll need at least enough space to put the Owner Option
-
- // Put query questions in this packet
- for (q = m->Questions; q && q != m->NewQuestions; q=q->next)
- {
- if (mDNSOpaque16IsZero(q->TargetQID) && (q->SendQNow == intf->InterfaceID))
- {
- debugf("SendQueries: %s question for %##s (%s) at %d forecast total %d",
- SuppressOnThisInterface(q->DupSuppress, intf) ? "Suppressing" : "Putting ",
- q->qname.c, DNSTypeName(q->qtype), queryptr - m->omsg.data, queryptr + answerforecast - m->omsg.data);
-
- // If we're suppressing this question, or we successfully put it, update its SendQNow state
- if (SuppressOnThisInterface(q->DupSuppress, intf) ||
- BuildQuestion(m, &m->omsg, &queryptr, q, &kalistptr, &answerforecast))
- {
- q->SendQNow = (q->InterfaceID || !q->SendOnAll) ? mDNSNULL : GetNextActiveInterfaceID(intf);
- if (q->WakeOnResolveCount)
- {
- mDNSSendWakeOnResolve(m, q);
- q->WakeOnResolveCount--;
- }
- }
- }
- }
-
- // Put probe questions in this packet
- for (ar = m->ResourceRecords; ar; ar=ar->next)
- if (ar->SendRNow == intf->InterfaceID)
- {
- mDNSBool ucast = (ar->ProbeCount >= DefaultProbeCountForTypeUnique-1) && m->CanReceiveUnicastOn5353;
- mDNSu16 ucbit = (mDNSu16)(ucast ? kDNSQClass_UnicastResponse : 0);
- const mDNSu8 *const limit = m->omsg.data + (m->omsg.h.numQuestions ? NormalMaxDNSMessageData : AbsoluteMaxDNSMessageData);
- // We forecast: compressed name (2) type (2) class (2) TTL (4) rdlength (2) rdata (n)
- mDNSu32 forecast = answerforecast + 12 + ar->resrec.rdestimate;
- mDNSu8 *newptr = putQuestion(&m->omsg, queryptr, limit - forecast, ar->resrec.name, kDNSQType_ANY, (mDNSu16)(ar->resrec.rrclass | ucbit));
- if (newptr)
- {
- queryptr = newptr;
- answerforecast = forecast;
- ar->SendRNow = (ar->resrec.InterfaceID) ? mDNSNULL : GetNextActiveInterfaceID(intf);
- ar->IncludeInProbe = mDNStrue;
- verbosedebugf("SendQueries: Put Question %##s (%s) probecount %d",
- ar->resrec.name->c, DNSTypeName(ar->resrec.rrtype), ar->ProbeCount);
- }
- }
- }
-
- // Put our known answer list (either new one from this question or questions, or remainder of old one from last time)
- while (KnownAnswerList)
- {
- CacheRecord *ka = KnownAnswerList;
- mDNSu32 SecsSinceRcvd = ((mDNSu32)(m->timenow - ka->TimeRcvd)) / mDNSPlatformOneSecond;
- mDNSu8 *newptr = PutResourceRecordTTLWithLimit(&m->omsg, queryptr, &m->omsg.h.numAnswers,
- &ka->resrec, ka->resrec.rroriginalttl - SecsSinceRcvd, m->omsg.data + NormalMaxDNSMessageData - OwnerRecordSpace);
- if (newptr)
- {
- verbosedebugf("SendQueries: Put %##s (%s) at %d - %d",
- ka->resrec.name->c, DNSTypeName(ka->resrec.rrtype), queryptr - m->omsg.data, newptr - m->omsg.data);
- queryptr = newptr;
- KnownAnswerList = ka->NextInKAList;
- ka->NextInKAList = mDNSNULL;
- }
- else
- {
- // If we ran out of space and we have more than one question in the packet, that's an error --
- // we shouldn't have put more than one question if there was a risk of us running out of space.
- if (m->omsg.h.numQuestions > 1)
- LogMsg("SendQueries: Put %d answers; No more space for known answers", m->omsg.h.numAnswers);
- m->omsg.h.flags.b[0] |= kDNSFlag0_TC;
- break;
- }
- }
-
- for (ar = m->ResourceRecords; ar; ar=ar->next)
- if (ar->IncludeInProbe)
- {
- mDNSu8 *newptr = PutResourceRecord(&m->omsg, queryptr, &m->omsg.h.numAuthorities, &ar->resrec);
- ar->IncludeInProbe = mDNSfalse;
- if (newptr) queryptr = newptr;
- else LogMsg("SendQueries: How did we fail to have space for the Update record %s", ARDisplayString(m,ar));
- }
-
- if (queryptr > m->omsg.data)
- {
- if (OwnerRecordSpace)
- {
- AuthRecord opt;
- mDNS_SetupResourceRecord(&opt, mDNSNULL, mDNSInterface_Any, kDNSType_OPT, kStandardTTL, kDNSRecordTypeKnownUnique, AuthRecordAny, mDNSNULL, mDNSNULL);
- opt.resrec.rrclass = NormalMaxDNSMessageData;
- opt.resrec.rdlength = sizeof(rdataOPT); // One option in this OPT record
- opt.resrec.rdestimate = sizeof(rdataOPT);
- SetupOwnerOpt(m, intf, &opt.resrec.rdata->u.opt[0]);
- LogSPS("SendQueries putting %s", ARDisplayString(m, &opt));
- queryptr = PutResourceRecordTTLWithLimit(&m->omsg, queryptr, &m->omsg.h.numAdditionals,
- &opt.resrec, opt.resrec.rroriginalttl, m->omsg.data + AbsoluteMaxDNSMessageData);
- if (!queryptr)
- LogMsg("SendQueries: How did we fail to have space for the OPT record (%d/%d/%d/%d) %s",
- m->omsg.h.numQuestions, m->omsg.h.numAnswers, m->omsg.h.numAuthorities, m->omsg.h.numAdditionals, ARDisplayString(m, &opt));
- if (queryptr > m->omsg.data + NormalMaxDNSMessageData)
- if (m->omsg.h.numQuestions != 1 || m->omsg.h.numAnswers != 0 || m->omsg.h.numAuthorities != 1 || m->omsg.h.numAdditionals != 1)
- LogMsg("SendQueries: Why did we generate oversized packet with OPT record %p %p %p (%d/%d/%d/%d) %s",
- m->omsg.data, m->omsg.data + NormalMaxDNSMessageData, queryptr,
- m->omsg.h.numQuestions, m->omsg.h.numAnswers, m->omsg.h.numAuthorities, m->omsg.h.numAdditionals, ARDisplayString(m, &opt));
- }
-
- if ((m->omsg.h.flags.b[0] & kDNSFlag0_TC) && m->omsg.h.numQuestions > 1)
- LogMsg("SendQueries: Should not have more than one question (%d) in a truncated packet", m->omsg.h.numQuestions);
- debugf("SendQueries: Sending %d Question%s %d Answer%s %d Update%s on %p",
- m->omsg.h.numQuestions, m->omsg.h.numQuestions == 1 ? "" : "s",
- m->omsg.h.numAnswers, m->omsg.h.numAnswers == 1 ? "" : "s",
- m->omsg.h.numAuthorities, m->omsg.h.numAuthorities == 1 ? "" : "s", intf->InterfaceID);
- if (intf->IPv4Available) mDNSSendDNSMessage(m, &m->omsg, queryptr, intf->InterfaceID, mDNSNULL, &AllDNSLinkGroup_v4, MulticastDNSPort, mDNSNULL, mDNSNULL);
- if (intf->IPv6Available) mDNSSendDNSMessage(m, &m->omsg, queryptr, intf->InterfaceID, mDNSNULL, &AllDNSLinkGroup_v6, MulticastDNSPort, mDNSNULL, mDNSNULL);
- if (!m->SuppressSending) m->SuppressSending = NonZeroTime(m->timenow + (mDNSPlatformOneSecond+9)/10);
- if (++pktcount >= 1000)
- { LogMsg("SendQueries exceeded loop limit %d: giving up", pktcount); break; }
- // There might be more records left in the known answer list, or more questions to send
- // on this interface, so go around one more time and try again.
- }
- else // Nothing more to send on this interface; go to next
- {
- const NetworkInterfaceInfo *next = GetFirstActiveInterface(intf->next);
- #if MDNS_DEBUGMSGS && 0
- const char *const msg = next ? "SendQueries: Nothing more on %p; moving to %p" : "SendQueries: Nothing more on %p";
- debugf(msg, intf, next);
- #endif
- intf = next;
- }
- }
-
- // 4. Final housekeeping
-
- // 4a. Debugging check: Make sure we announced all our records
- for (ar = m->ResourceRecords; ar; ar=ar->next)
- if (ar->SendRNow)
- {
- if (ar->ARType != AuthRecordLocalOnly && ar->ARType != AuthRecordP2P)
- LogMsg("SendQueries: No active interface %p to send probe: %p %s", ar->SendRNow, ar->resrec.InterfaceID, ARDisplayString(m, ar));
- ar->SendRNow = mDNSNULL;
- }
-
- // 4b. When we have lingering cache records that we're keeping around for a few seconds in the hope
- // that their interface which went away might come back again, the logic will want to send queries
- // for those records, but we can't because their interface isn't here any more, so to keep the
- // state machine ticking over we just pretend we did so.
- // If the interface does not come back in time, the cache record will expire naturally
- FORALL_CACHERECORDS(slot, cg, cr)
- if (cr->CRActiveQuestion && cr->UnansweredQueries < MaxUnansweredQueries)
- if (m->timenow + TicksTTL(cr)/50 - cr->NextRequiredQuery >= 0)
- {
- cr->UnansweredQueries++;
- cr->CRActiveQuestion->SendQNow = mDNSNULL;
- SetNextCacheCheckTimeForRecord(m, cr);
- }
-
- // 4c. Debugging check: Make sure we sent all our planned questions
- // Do this AFTER the lingering cache records check above, because that will prevent spurious warnings for questions
- // we legitimately couldn't send because the interface is no longer available
- for (q = m->Questions; q; q=q->next)
- if (q->SendQNow)
- {
- DNSQuestion *x;
- for (x = m->NewQuestions; x; x=x->next) if (x == q) break; // Check if this question is a NewQuestion
- LogMsg("SendQueries: No active interface %p to send %s question: %p %##s (%s)", q->SendQNow, x ? "new" : "old", q->InterfaceID, q->qname.c, DNSTypeName(q->qtype));
- q->SendQNow = mDNSNULL;
- }
- }
+{
+ mDNSu32 slot;
+ CacheGroup *cg;
+ CacheRecord *cr;
+ AuthRecord *ar;
+ int pktcount = 0;
+ DNSQuestion *q;
+ // For explanation of maxExistingQuestionInterval logic, see comments for maxExistingAnnounceInterval
+ mDNSs32 maxExistingQuestionInterval = 0;
+ const NetworkInterfaceInfo *intf = GetFirstActiveInterface(m->HostInterfaces);
+ CacheRecord *KnownAnswerList = mDNSNULL;
+
+ // 1. If time for a query, work out what we need to do
+
+ // We're expecting to send a query anyway, so see if any expiring cache records are close enough
+ // to their NextRequiredQuery to be worth batching them together with this one
+ FORALL_CACHERECORDS(slot, cg, cr)
+ {
+ if (cr->CRActiveQuestion && cr->UnansweredQueries < MaxUnansweredQueries)
+ {
+ if (m->timenow + TicksTTL(cr)/50 - cr->NextRequiredQuery >= 0)
+ {
+ debugf("Sending %d%% cache expiration query for %s", 80 + 5 * cr->UnansweredQueries, CRDisplayString(m, cr));
+ q = cr->CRActiveQuestion;
+ ExpireDupSuppressInfoOnInterface(q->DupSuppress, m->timenow - TicksTTL(cr)/20, cr->resrec.InterfaceID);
+ // For uDNS queries (TargetQID non-zero) we adjust LastQTime,
+ // and bump UnansweredQueries so that we don't spin trying to send the same cache expiration query repeatedly
+ if (q->Target.type)
+ {
+ q->SendQNow = mDNSInterfaceMark; // If targeted query, mark it
+ }
+ else if (!mDNSOpaque16IsZero(q->TargetQID))
+ {
+ q->LastQTime = m->timenow - q->ThisQInterval;
+ cr->UnansweredQueries++;
+ m->mDNSStats.CacheRefreshQueries++;
+ }
+ else if (q->SendQNow == mDNSNULL)
+ {
+ q->SendQNow = cr->resrec.InterfaceID;
+ }
+ else if (q->SendQNow != cr->resrec.InterfaceID)
+ {
+ q->SendQNow = mDNSInterfaceMark;
+ }
+
+ // Indicate that this question was marked for sending
+ // to update an existing cached answer record.
+ // The browse throttling logic below uses this to determine
+ // if the query should be sent.
+ if (mDNSOpaque16IsZero(q->TargetQID))
+ q->CachedAnswerNeedsUpdate = mDNStrue;
+ }
+ }
+ }
+
+ // Scan our list of questions to see which:
+ // *WideArea* queries need to be sent
+ // *unicast* queries need to be sent
+ // *multicast* queries we're definitely going to send
+ if (m->CurrentQuestion)
+ LogMsg("SendQueries ERROR m->CurrentQuestion already set: %##s (%s)", m->CurrentQuestion->qname.c, DNSTypeName(m->CurrentQuestion->qtype));
+ m->CurrentQuestion = m->Questions;
+ while (m->CurrentQuestion && m->CurrentQuestion != m->NewQuestions)
+ {
+ q = m->CurrentQuestion;
+ if (q->Target.type && (q->SendQNow || TimeToSendThisQuestion(q, m->timenow)))
+ {
+ mDNSu8 *qptr = m->omsg.data;
+ const mDNSu8 *const limit = m->omsg.data + sizeof(m->omsg.data);
+
+ // If we fail to get a new on-demand socket (should only happen cases of the most extreme resource exhaustion), we'll try again next time
+ if (!q->LocalSocket) q->LocalSocket = mDNSPlatformUDPSocket(m, zeroIPPort);
+ if (q->LocalSocket)
+ {
+ InitializeDNSMessage(&m->omsg.h, q->TargetQID, QueryFlags);
+ qptr = putQuestion(&m->omsg, qptr, limit, &q->qname, q->qtype, q->qclass);
+ mDNSSendDNSMessage(m, &m->omsg, qptr, mDNSInterface_Any, q->LocalSocket, &q->Target, q->TargetPort, mDNSNULL, mDNSNULL, q->UseBackgroundTrafficClass);
+ q->ThisQInterval *= QuestionIntervalStep;
+ }
+ if (q->ThisQInterval > MaxQuestionInterval)
+ q->ThisQInterval = MaxQuestionInterval;
+ q->LastQTime = m->timenow;
+ q->LastQTxTime = m->timenow;
+ q->RecentAnswerPkts = 0;
+ q->SendQNow = mDNSNULL;
+ q->ExpectUnicastResp = NonZeroTime(m->timenow);
+ }
+ else if (mDNSOpaque16IsZero(q->TargetQID) && !q->Target.type && TimeToSendThisQuestion(q, m->timenow))
+ {
+ //LogInfo("Time to send %##s (%s) %d", q->qname.c, DNSTypeName(q->qtype), m->timenow - NextQSendTime(q));
+ q->SendQNow = mDNSInterfaceMark; // Mark this question for sending on all interfaces
+ if (maxExistingQuestionInterval < q->ThisQInterval)
+ maxExistingQuestionInterval = q->ThisQInterval;
+ }
+ // If m->CurrentQuestion wasn't modified out from under us, advance it now
+ // We can't do this at the start of the loop because uDNS_CheckCurrentQuestion() depends on having
+ // m->CurrentQuestion point to the right question
+ if (q == m->CurrentQuestion) m->CurrentQuestion = m->CurrentQuestion->next;
+ }
+ while (m->CurrentQuestion)
+ {
+ LogInfo("SendQueries question loop 1: Skipping NewQuestion %##s (%s)", m->CurrentQuestion->qname.c, DNSTypeName(m->CurrentQuestion->qtype));
+ m->CurrentQuestion = m->CurrentQuestion->next;
+ }
+ m->CurrentQuestion = mDNSNULL;
+
+ // Scan our list of questions
+ // (a) to see if there are any more that are worth accelerating, and
+ // (b) to update the state variables for *all* the questions we're going to send
+ // Note: Don't set NextScheduledQuery until here, because uDNS_CheckCurrentQuestion in the loop above can add new questions to the list,
+ // which causes NextScheduledQuery to get (incorrectly) set to m->timenow. Setting it here is the right place, because the very
+ // next thing we do is scan the list and call SetNextQueryTime() for every question we find, so we know we end up with the right value.
+ m->NextScheduledQuery = m->timenow + 0x78000000;
+ for (q = m->Questions; q && q != m->NewQuestions; q=q->next)
+ {
+ if (mDNSOpaque16IsZero(q->TargetQID)
+ && (q->SendQNow || (!q->Target.type && ActiveQuestion(q) && q->ThisQInterval <= maxExistingQuestionInterval && AccelerateThisQuery(m,q))))
+ {
+ // If at least halfway to next query time, advance to next interval
+ // If less than halfway to next query time, then
+ // treat this as logically a repeat of the last transmission, without advancing the interval
+ if (m->timenow - (q->LastQTime + (q->ThisQInterval/2)) >= 0)
+ {
+ // If we have reached the answer threshold for this question,
+ // don't send it again until MaxQuestionInterval unless:
+ // one of its cached answers needs to be refreshed,
+ // or it's the initial query for a kDNSServiceFlagsThresholdFinder mode browse.
+ if (q->BrowseThreshold
+ && (q->CurrentAnswers >= q->BrowseThreshold)
+ && (q->CachedAnswerNeedsUpdate == mDNSfalse)
+ && !((q->flags & kDNSServiceFlagsThresholdFinder) && (q->ThisQInterval == InitialQuestionInterval)))
+ {
+ q->SendQNow = mDNSNULL;
+ q->ThisQInterval = MaxQuestionInterval;
+ q->LastQTime = m->timenow;
+ q->RequestUnicast = 0;
+ LogInfo("SendQueries: (%s) %##s reached threshold of %d answers",
+ DNSTypeName(q->qtype), q->qname.c, q->BrowseThreshold);
+ }
+ else
+ {
+ // Mark this question for sending on all interfaces
+ q->SendQNow = mDNSInterfaceMark;
+ q->ThisQInterval *= QuestionIntervalStep;
+ }
+
+ debugf("SendQueries: %##s (%s) next interval %d seconds RequestUnicast = %d",
+ q->qname.c, DNSTypeName(q->qtype), q->ThisQInterval / InitialQuestionInterval, q->RequestUnicast);
+
+ if (q->ThisQInterval >= QuestionIntervalThreshold)
+ {
+ q->ThisQInterval = MaxQuestionInterval;
+ }
+ else if (q->CurrentAnswers == 0 && q->ThisQInterval == InitialQuestionInterval * QuestionIntervalStep3 && !q->RequestUnicast &&
+ !(RRTypeIsAddressType(q->qtype) && CacheHasAddressTypeForName(m, &q->qname, q->qnamehash)))
+ {
+ // Generally don't need to log this.
+ // It's not especially noteworthy if a query finds no results -- this usually happens for domain
+ // enumeration queries in the LL subdomain (e.g. "db._dns-sd._udp.0.0.254.169.in-addr.arpa")
+ // and when there simply happen to be no instances of the service the client is looking
+ // for (e.g. iTunes is set to look for RAOP devices, and the current network has none).
+ debugf("SendQueries: Zero current answers for %##s (%s); will reconfirm antecedents",
+ q->qname.c, DNSTypeName(q->qtype));
+ // Sending third query, and no answers yet; time to begin doubting the source
+ ReconfirmAntecedents(m, &q->qname, q->qnamehash, 0);
+ }
+ }
+
+ // Mark for sending. (If no active interfaces, then don't even try.)
+ q->SendOnAll = (q->SendQNow == mDNSInterfaceMark);
+ if (q->SendOnAll)
+ {
+ q->SendQNow = !intf ? mDNSNULL : (q->InterfaceID) ? q->InterfaceID : intf->InterfaceID;
+ q->LastQTime = m->timenow;
+ }
+
+ // If we recorded a duplicate suppression for this question less than half an interval ago,
+ // then we consider it recent enough that we don't need to do an identical query ourselves.
+ ExpireDupSuppressInfo(q->DupSuppress, m->timenow - q->ThisQInterval/2);
+
+ q->LastQTxTime = m->timenow;
+ q->RecentAnswerPkts = 0;
+ if (q->RequestUnicast) q->RequestUnicast--;
+ }
+ // For all questions (not just the ones we're sending) check what the next scheduled event will be
+ // We don't need to consider NewQuestions here because for those we'll set m->NextScheduledQuery in AnswerNewQuestion
+ SetNextQueryTime(m,q);
+ }
+
+ // 2. Scan our authoritative RR list to see what probes we might need to send
+
+ m->NextScheduledProbe = m->timenow + 0x78000000;
+
+ if (m->CurrentRecord)
+ LogMsg("SendQueries ERROR m->CurrentRecord already set %s", ARDisplayString(m, m->CurrentRecord));
+ m->CurrentRecord = m->ResourceRecords;
+ while (m->CurrentRecord)
+ {
+ ar = m->CurrentRecord;
+ m->CurrentRecord = ar->next;
+ if (!AuthRecord_uDNS(ar) && ar->resrec.RecordType == kDNSRecordTypeUnique) // For all records that are still probing...
+ {
+ // 1. If it's not reached its probe time, just make sure we update m->NextScheduledProbe correctly
+ if (m->timenow - (ar->LastAPTime + ar->ThisAPInterval) < 0)
+ {
+ SetNextAnnounceProbeTime(m, ar);
+ }
+ // 2. else, if it has reached its probe time, mark it for sending and then update m->NextScheduledProbe correctly
+ else if (ar->ProbeCount)
+ {
+ if (ar->AddressProxy.type == mDNSAddrType_IPv4)
+ {
+ // There's a problem here. If a host is waking up, and we probe to see if it responds, then
+ // it will see those ARP probes as signalling intent to use the address, so it picks a different one.
+ // A more benign way to find out if a host is responding to ARPs might be send a standard ARP *request*
+ // (using our sender IP address) instead of an ARP *probe* (using all-zero sender IP address).
+ // A similar concern may apply to the NDP Probe too. -- SC
+ LogSPS("SendQueries ARP Probe %d %s %s", ar->ProbeCount, InterfaceNameForID(m, ar->resrec.InterfaceID), ARDisplayString(m,ar));
+ SendARP(m, 1, ar, &zerov4Addr, &zeroEthAddr, &ar->AddressProxy.ip.v4, &ar->WakeUp.IMAC);
+ }
+ else if (ar->AddressProxy.type == mDNSAddrType_IPv6)
+ {
+ LogSPS("SendQueries NDP Probe %d %s %s", ar->ProbeCount, InterfaceNameForID(m, ar->resrec.InterfaceID), ARDisplayString(m,ar));
+ // IPv6 source = zero
+ // No target hardware address
+ // IPv6 target address is address we're probing
+ // Ethernet destination address is Ethernet interface address of the Sleep Proxy client we're probing
+ SendNDP(m, NDP_Sol, 0, ar, &zerov6Addr, mDNSNULL, &ar->AddressProxy.ip.v6, &ar->WakeUp.IMAC);
+ }
+ // Mark for sending. (If no active interfaces, then don't even try.)
+ ar->SendRNow = (!intf || ar->WakeUp.HMAC.l[0]) ? mDNSNULL : ar->resrec.InterfaceID ? ar->resrec.InterfaceID : intf->InterfaceID;
+ ar->LastAPTime = m->timenow;
+ // When we have a late conflict that resets a record to probing state we use a special marker value greater
+ // than DefaultProbeCountForTypeUnique. Here we detect that state and reset ar->ProbeCount back to the right value.
+ if (ar->ProbeCount > DefaultProbeCountForTypeUnique)
+ ar->ProbeCount = DefaultProbeCountForTypeUnique;
+ ar->ProbeCount--;
+ SetNextAnnounceProbeTime(m, ar);
+ if (ar->ProbeCount == 0)
+ {
+ // If this is the last probe for this record, then see if we have any matching records
+ // on our duplicate list which should similarly have their ProbeCount cleared to zero...
+ AuthRecord *r2;
+ for (r2 = m->DuplicateRecords; r2; r2=r2->next)
+ if (r2->resrec.RecordType == kDNSRecordTypeUnique && RecordIsLocalDuplicate(r2, ar))
+ r2->ProbeCount = 0;
+ // ... then acknowledge this record to the client.
+ // We do this optimistically, just as we're about to send the third probe.
+ // This helps clients that both advertise and browse, and want to filter themselves
+ // from the browse results list, because it helps ensure that the registration
+ // confirmation will be delivered 1/4 second *before* the browse "add" event.
+ // A potential downside is that we could deliver a registration confirmation and then find out
+ // moments later that there's a name conflict, but applications have to be prepared to handle
+ // late conflicts anyway (e.g. on connection of network cable, etc.), so this is nothing new.
+ if (!ar->Acknowledged) AcknowledgeRecord(m, ar);
+ }
+ }
+ // else, if it has now finished probing, move it to state Verified,
+ // and update m->NextScheduledResponse so it will be announced
+ else
+ {
+ if (!ar->Acknowledged) AcknowledgeRecord(m, ar); // Defensive, just in case it got missed somehow
+ ar->resrec.RecordType = kDNSRecordTypeVerified;
+ ar->ThisAPInterval = DefaultAnnounceIntervalForTypeUnique;
+ ar->LastAPTime = m->timenow - DefaultAnnounceIntervalForTypeUnique;
+ SetNextAnnounceProbeTime(m, ar);
+ }
+ }
+ }
+ m->CurrentRecord = m->DuplicateRecords;
+ while (m->CurrentRecord)
+ {
+ ar = m->CurrentRecord;
+ m->CurrentRecord = ar->next;
+ if (ar->resrec.RecordType == kDNSRecordTypeUnique && ar->ProbeCount == 0 && !ar->Acknowledged)
+ AcknowledgeRecord(m, ar);
+ }
+
+ // 3. Now we know which queries and probes we're sending,
+ // go through our interface list sending the appropriate queries on each interface
+ while (intf)
+ {
+ int OwnerRecordSpace = (m->AnnounceOwner && intf->MAC.l[0]) ? DNSOpt_Header_Space + DNSOpt_Owner_Space(&m->PrimaryMAC, &intf->MAC) : 0;
+ int TraceRecordSpace = (mDNS_McastTracingEnabled && MDNS_TRACER) ? DNSOpt_Header_Space + DNSOpt_TraceData_Space : 0;
+ mDNSu8 *queryptr = m->omsg.data;
+ mDNSBool useBackgroundTrafficClass = mDNSfalse; // set if we should use background traffic class
+
+ InitializeDNSMessage(&m->omsg.h, zeroID, QueryFlags);
+ if (KnownAnswerList) verbosedebugf("SendQueries: KnownAnswerList set... Will continue from previous packet");
+ if (!KnownAnswerList)
+ {
+ // Start a new known-answer list
+ CacheRecord **kalistptr = &KnownAnswerList;
+ mDNSu32 answerforecast = OwnerRecordSpace + TraceRecordSpace; // Start by assuming we'll need at least enough space to put the Owner+Tracer Option
+
+ // Put query questions in this packet
+ for (q = m->Questions; q && q != m->NewQuestions; q=q->next)
+ {
+ if (mDNSOpaque16IsZero(q->TargetQID) && (q->SendQNow == intf->InterfaceID))
+ {
+ mDNSBool Suppress = mDNSfalse;
+ debugf("SendQueries: %s question for %##s (%s) at %d forecast total %d",
+ SuppressOnThisInterface(q->DupSuppress, intf) ? "Suppressing" : "Putting ",
+ q->qname.c, DNSTypeName(q->qtype), queryptr - m->omsg.data, queryptr + answerforecast - m->omsg.data);
+
+ // If interface is P2P type, verify that query should be sent over it.
+ if (!mDNSPlatformValidQuestionForInterface(q, intf))
+ {
+ LogInfo("SendQueries: Not sending (%s) %##s on %s", DNSTypeName(q->qtype), q->qname.c, InterfaceNameForID(m, intf->InterfaceID));
+ q->SendQNow = (q->InterfaceID || !q->SendOnAll) ? mDNSNULL : GetNextActiveInterfaceID(intf);
+ }
+ // If we're suppressing this question, or we successfully put it, update its SendQNow state
+ else if ((Suppress = SuppressOnThisInterface(q->DupSuppress, intf)) ||
+ BuildQuestion(m, &m->omsg, &queryptr, q, &kalistptr, &answerforecast))
+ {
+ // We successfully added the question to the packet. Make sure that
+ // we also send the NSEC3 record if required. BuildQuestion accounted for
+ // the space.
+ //
+ // Note: We don't suppress anonymous questions and hence Suppress should always
+ // be zero.
+
+ if (Suppress)
+ m->mDNSStats.DupQuerySuppressions++;
+
+ if (!Suppress && q->AnonInfo)
+ {
+ debugf("SendQueries: marking for question %##s, Suppress %d", q->qname.c, Suppress);
+ q->AnonInfo->SendNow = intf->InterfaceID;
+ }
+ q->SendQNow = (q->InterfaceID || !q->SendOnAll) ? mDNSNULL : GetNextActiveInterfaceID(intf);
+ if (q->WakeOnResolveCount)
+ {
+ mDNSSendWakeOnResolve(m, q);
+ q->WakeOnResolveCount--;
+ }
+
+ // use brackground traffic class if any included question requires it
+ if (q->UseBackgroundTrafficClass)
+ {
+ useBackgroundTrafficClass = mDNStrue;
+ }
+ }
+ }
+ }
+
+ // Put probe questions in this packet
+ for (ar = m->ResourceRecords; ar; ar=ar->next)
+ if (ar->SendRNow == intf->InterfaceID)
+ {
+ mDNSBool ucast = (ar->ProbeCount >= DefaultProbeCountForTypeUnique-1) && m->CanReceiveUnicastOn5353;
+ mDNSu16 ucbit = (mDNSu16)(ucast ? kDNSQClass_UnicastResponse : 0);
+ const mDNSu8 *const limit = m->omsg.data + (m->omsg.h.numQuestions ? NormalMaxDNSMessageData : AbsoluteMaxDNSMessageData);
+ // We forecast: compressed name (2) type (2) class (2) TTL (4) rdlength (2) rdata (n)
+ mDNSu32 forecast = answerforecast + 12 + ar->resrec.rdestimate;
+ mDNSu8 *newptr = putQuestion(&m->omsg, queryptr, limit - forecast, ar->resrec.name, kDNSQType_ANY, (mDNSu16)(ar->resrec.rrclass | ucbit));
+ if (newptr)
+ {
+ queryptr = newptr;
+ answerforecast = forecast;
+ ar->SendRNow = (ar->resrec.InterfaceID) ? mDNSNULL : GetNextActiveInterfaceID(intf);
+ ar->IncludeInProbe = mDNStrue;
+ verbosedebugf("SendQueries: Put Question %##s (%s) probecount %d",
+ ar->resrec.name->c, DNSTypeName(ar->resrec.rrtype), ar->ProbeCount);
+ }
+ }
+ }
+
+ // Put our known answer list (either new one from this question or questions, or remainder of old one from last time)
+ while (KnownAnswerList)
+ {
+ CacheRecord *ka = KnownAnswerList;
+ mDNSu32 SecsSinceRcvd = ((mDNSu32)(m->timenow - ka->TimeRcvd)) / mDNSPlatformOneSecond;
+ mDNSu8 *newptr = PutResourceRecordTTLWithLimit(&m->omsg, queryptr, &m->omsg.h.numAnswers, &ka->resrec, ka->resrec.rroriginalttl - SecsSinceRcvd,
+ m->omsg.data + NormalMaxDNSMessageData - OwnerRecordSpace - TraceRecordSpace);
+ if (newptr)
+ {
+ verbosedebugf("SendQueries: Put %##s (%s) at %d - %d",
+ ka->resrec.name->c, DNSTypeName(ka->resrec.rrtype), queryptr - m->omsg.data, newptr - m->omsg.data);
+ queryptr = newptr;
+ KnownAnswerList = ka->NextInKAList;
+ ka->NextInKAList = mDNSNULL;
+ }
+ else
+ {
+ // If we ran out of space and we have more than one question in the packet, that's an error --
+ // we shouldn't have put more than one question if there was a risk of us running out of space.
+ if (m->omsg.h.numQuestions > 1)
+ LogMsg("SendQueries: Put %d answers; No more space for known answers", m->omsg.h.numAnswers);
+ m->omsg.h.flags.b[0] |= kDNSFlag0_TC;
+ break;
+ }
+ }
+
+ for (ar = m->ResourceRecords; ar; ar=ar->next)
+ {
+ if (ar->IncludeInProbe)
+ {
+ mDNSu8 *newptr = PutResourceRecord(&m->omsg, queryptr, &m->omsg.h.numAuthorities, &ar->resrec);
+ ar->IncludeInProbe = mDNSfalse;
+ if (newptr) queryptr = newptr;
+ else LogMsg("SendQueries: How did we fail to have space for the Update record %s", ARDisplayString(m,ar));
+ }
+ }
+
+ for (q = m->Questions; q; q = q->next)
+ {
+ if (q->AnonInfo && q->AnonInfo->SendNow == intf->InterfaceID)
+ {
+ mDNSu8 *newptr = PutResourceRecord(&m->omsg, queryptr, &m->omsg.h.numAuthorities, q->AnonInfo->nsec3RR);
+ if (newptr)
+ {
+ debugf("SendQueries: Added NSEC3 record %s on InterfaceID %p", RRDisplayString(m, q->AnonInfo->nsec3RR), intf->InterfaceID);
+ queryptr = newptr;
+ }
+ else
+ {
+ LogMsg("SendQueries: ERROR!! Cannot add NSEC3 record %s on InterfaceID %p", RRDisplayString(m, q->AnonInfo->nsec3RR), intf->InterfaceID);
+ }
+ q->AnonInfo->SendNow = mDNSNULL;
+ }
+ }
+
+ if (queryptr > m->omsg.data)
+ {
+ // If we have data to send, add OWNER/TRACER/OWNER+TRACER option if necessary, then send packet
+ if (OwnerRecordSpace || TraceRecordSpace)
+ {
+ AuthRecord opt;
+ mDNS_SetupResourceRecord(&opt, mDNSNULL, mDNSInterface_Any, kDNSType_OPT, kStandardTTL, kDNSRecordTypeKnownUnique, AuthRecordAny, mDNSNULL, mDNSNULL);
+ opt.resrec.rrclass = NormalMaxDNSMessageData;
+ opt.resrec.rdlength = sizeof(rdataOPT);
+ opt.resrec.rdestimate = sizeof(rdataOPT);
+ if (OwnerRecordSpace && TraceRecordSpace)
+ {
+ opt.resrec.rdlength += sizeof(rdataOPT); // Two options in this OPT record
+ opt.resrec.rdestimate += sizeof(rdataOPT);
+ SetupOwnerOpt(m, intf, &opt.resrec.rdata->u.opt[0]);
+ SetupTracerOpt(m, &opt.resrec.rdata->u.opt[1]);
+ }
+ else if (OwnerRecordSpace)
+ {
+ SetupOwnerOpt(m, intf, &opt.resrec.rdata->u.opt[0]);
+ }
+ else if (TraceRecordSpace)
+ {
+ SetupTracerOpt(m, &opt.resrec.rdata->u.opt[0]);
+ }
+ LogInfo("SendQueries putting %s %s: %s %s", OwnerRecordSpace ? "OWNER" : "", TraceRecordSpace ? "TRACER" : "", intf->ifname, ARDisplayString(m, &opt));
+ queryptr = PutResourceRecordTTLWithLimit(&m->omsg, queryptr, &m->omsg.h.numAdditionals,
+ &opt.resrec, opt.resrec.rroriginalttl, m->omsg.data + AbsoluteMaxDNSMessageData);
+ if (!queryptr)
+ {
+ LogMsg("SendQueries: How did we fail to have space for %s %s OPT record (%d/%d/%d/%d) %s", OwnerRecordSpace ? "OWNER" : "", TraceRecordSpace ? "TRACER" : "",
+ m->omsg.h.numQuestions, m->omsg.h.numAnswers, m->omsg.h.numAuthorities, m->omsg.h.numAdditionals, ARDisplayString(m, &opt));
+ }
+ if (queryptr > m->omsg.data + NormalMaxDNSMessageData)
+ {
+ if (m->omsg.h.numQuestions != 1 || m->omsg.h.numAnswers != 0 || m->omsg.h.numAuthorities != 1 || m->omsg.h.numAdditionals != 1)
+ LogMsg("SendQueries: Why did we generate oversized packet with %s %s OPT record %p %p %p (%d/%d/%d/%d) %s", OwnerRecordSpace ? "OWNER" : "",
+ TraceRecordSpace ? "TRACER" : "", m->omsg.data, m->omsg.data + NormalMaxDNSMessageData, queryptr, m->omsg.h.numQuestions, m->omsg.h.numAnswers,
+ m->omsg.h.numAuthorities, m->omsg.h.numAdditionals, ARDisplayString(m, &opt));
+ }
+ }
+
+ if ((m->omsg.h.flags.b[0] & kDNSFlag0_TC) && m->omsg.h.numQuestions > 1)
+ LogMsg("SendQueries: Should not have more than one question (%d) in a truncated packet", m->omsg.h.numQuestions);
+ debugf("SendQueries: Sending %d Question%s %d Answer%s %d Update%s on %p",
+ m->omsg.h.numQuestions, m->omsg.h.numQuestions == 1 ? "" : "s",
+ m->omsg.h.numAnswers, m->omsg.h.numAnswers == 1 ? "" : "s",
+ m->omsg.h.numAuthorities, m->omsg.h.numAuthorities == 1 ? "" : "s", intf->InterfaceID);
+ if (intf->IPv4Available) mDNSSendDNSMessage(m, &m->omsg, queryptr, intf->InterfaceID, mDNSNULL, &AllDNSLinkGroup_v4, MulticastDNSPort, mDNSNULL, mDNSNULL, useBackgroundTrafficClass);
+ if (intf->IPv6Available) mDNSSendDNSMessage(m, &m->omsg, queryptr, intf->InterfaceID, mDNSNULL, &AllDNSLinkGroup_v6, MulticastDNSPort, mDNSNULL, mDNSNULL, useBackgroundTrafficClass);
+ if (!m->SuppressSending) m->SuppressSending = NonZeroTime(m->timenow + (mDNSPlatformOneSecond+9)/10);
+ if (++pktcount >= 1000)
+ { LogMsg("SendQueries exceeded loop limit %d: giving up", pktcount); break; }
+ // There might be more records left in the known answer list, or more questions to send
+ // on this interface, so go around one more time and try again.
+ }
+ else // Nothing more to send on this interface; go to next
+ {
+ const NetworkInterfaceInfo *next = GetFirstActiveInterface(intf->next);
+ #if MDNS_DEBUGMSGS && 0
+ const char *const msg = next ? "SendQueries: Nothing more on %p; moving to %p" : "SendQueries: Nothing more on %p";
+ debugf(msg, intf, next);
+ #endif
+ intf = next;
+ }
+ }
+
+ // 4. Final housekeeping
+
+ // 4a. Debugging check: Make sure we announced all our records
+ for (ar = m->ResourceRecords; ar; ar=ar->next)
+ if (ar->SendRNow)
+ {
+ if (ar->ARType != AuthRecordLocalOnly && ar->ARType != AuthRecordP2P)
+ LogInfo("SendQueries: No active interface %d to send probe: %d %s",
+ (uint32_t)ar->SendRNow, (uint32_t)ar->resrec.InterfaceID, ARDisplayString(m, ar));
+ ar->SendRNow = mDNSNULL;
+ }
+
+ // 4b. When we have lingering cache records that we're keeping around for a few seconds in the hope
+ // that their interface which went away might come back again, the logic will want to send queries
+ // for those records, but we can't because their interface isn't here any more, so to keep the
+ // state machine ticking over we just pretend we did so.
+ // If the interface does not come back in time, the cache record will expire naturally
+ FORALL_CACHERECORDS(slot, cg, cr)
+ {
+ if (cr->CRActiveQuestion && cr->UnansweredQueries < MaxUnansweredQueries)
+ {
+ if (m->timenow + TicksTTL(cr)/50 - cr->NextRequiredQuery >= 0)
+ {
+ cr->UnansweredQueries++;
+ cr->CRActiveQuestion->SendQNow = mDNSNULL;
+ SetNextCacheCheckTimeForRecord(m, cr);
+ }
+ }
+ }
+
+ // 4c. Debugging check: Make sure we sent all our planned questions
+ // Do this AFTER the lingering cache records check above, because that will prevent spurious warnings for questions
+ // we legitimately couldn't send because the interface is no longer available
+ for (q = m->Questions; q; q=q->next)
+ {
+ if (q->SendQNow)
+ {
+ DNSQuestion *x;
+ for (x = m->NewQuestions; x; x=x->next) if (x == q) break; // Check if this question is a NewQuestion
+ LogInfo("SendQueries: No active interface %d to send %s question: %d %##s (%s)",
+ (uint32_t)q->SendQNow, x ? "new" : "old", (uint32_t)q->InterfaceID, q->qname.c, DNSTypeName(q->qtype));
+ q->SendQNow = mDNSNULL;
+ }
+ q->CachedAnswerNeedsUpdate = mDNSfalse;
+ }
+}
mDNSlocal void SendWakeup(mDNS *const m, mDNSInterfaceID InterfaceID, mDNSEthAddr *EthAddr, mDNSOpaque48 *password)
- {
- int i, j;
- mDNSu8 *ptr = m->omsg.data;
- NetworkInterfaceInfo *intf = FirstInterfaceForID(m, InterfaceID);
- if (!intf) { LogMsg("SendARP: No interface with InterfaceID %p found", InterfaceID); return; }
+{
+ int i, j;
+ mDNSu8 *ptr = m->omsg.data;
+ NetworkInterfaceInfo *intf = FirstInterfaceForID(m, InterfaceID);
+ if (!intf) { LogMsg("SendARP: No interface with InterfaceID %p found", InterfaceID); return; }
- // 0x00 Destination address
- for (i=0; i<6; i++) *ptr++ = EthAddr->b[i];
+ // 0x00 Destination address
+ for (i=0; i<6; i++) *ptr++ = EthAddr->b[i];
- // 0x06 Source address (Note: Since we don't currently set the BIOCSHDRCMPLT option, BPF will fill in the real interface address for us)
- for (i=0; i<6; i++) *ptr++ = intf->MAC.b[0];
+ // 0x06 Source address (Note: Since we don't currently set the BIOCSHDRCMPLT option, BPF will fill in the real interface address for us)
+ for (i=0; i<6; i++) *ptr++ = intf->MAC.b[0];
- // 0x0C Ethertype (0x0842)
- *ptr++ = 0x08;
- *ptr++ = 0x42;
+ // 0x0C Ethertype (0x0842)
+ *ptr++ = 0x08;
+ *ptr++ = 0x42;
- // 0x0E Wakeup sync sequence
- for (i=0; i<6; i++) *ptr++ = 0xFF;
+ // 0x0E Wakeup sync sequence
+ for (i=0; i<6; i++) *ptr++ = 0xFF;
- // 0x14 Wakeup data
- for (j=0; j<16; j++) for (i=0; i<6; i++) *ptr++ = EthAddr->b[i];
+ // 0x14 Wakeup data
+ for (j=0; j<16; j++) for (i=0; i<6; i++) *ptr++ = EthAddr->b[i];
- // 0x74 Password
- for (i=0; i<6; i++) *ptr++ = password->b[i];
+ // 0x74 Password
+ for (i=0; i<6; i++) *ptr++ = password->b[i];
- mDNSPlatformSendRawPacket(m->omsg.data, ptr, InterfaceID);
+ mDNSPlatformSendRawPacket(m->omsg.data, ptr, InterfaceID);
- // For Ethernet switches that don't flood-foward packets with unknown unicast destination MAC addresses,
- // broadcast is the only reliable way to get a wakeup packet to the intended target machine.
- // For 802.11 WPA networks, where a sleeping target machine may have missed a broadcast/multicast
- // key rotation, unicast is the only way to get a wakeup packet to the intended target machine.
- // So, we send one of each, unicast first, then broadcast second.
- for (i=0; i<6; i++) m->omsg.data[i] = 0xFF;
- mDNSPlatformSendRawPacket(m->omsg.data, ptr, InterfaceID);
- }
+ // For Ethernet switches that don't flood-foward packets with unknown unicast destination MAC addresses,
+ // broadcast is the only reliable way to get a wakeup packet to the intended target machine.
+ // For 802.11 WPA networks, where a sleeping target machine may have missed a broadcast/multicast
+ // key rotation, unicast is the only way to get a wakeup packet to the intended target machine.
+ // So, we send one of each, unicast first, then broadcast second.
+ for (i=0; i<6; i++) m->omsg.data[i] = 0xFF;
+ mDNSPlatformSendRawPacket(m->omsg.data, ptr, InterfaceID);
+}
// ***************************************************************************
#if COMPILER_LIKES_PRAGMA_MARK
#pragma mark - RR List Management & Task Management
#endif
+// Whenever a question is answered, reset its state so that we don't query
+// the network repeatedly. This happens first time when we answer the question and
+// and later when we refresh the cache.
+mDNSlocal void ResetQuestionState(mDNS *const m, DNSQuestion *q)
+{
+ q->LastQTime = m->timenow;
+ q->LastQTxTime = m->timenow;
+ q->RecentAnswerPkts = 0;
+ q->ThisQInterval = MaxQuestionInterval;
+ q->RequestUnicast = 0;
+ // Reset unansweredQueries so that we don't penalize this server later when we
+ // start sending queries when the cache expires.
+ q->unansweredQueries = 0;
+ debugf("ResetQuestionState: Set MaxQuestionInterval for %##s (%s)", q->qname.c, DNSTypeName(q->qtype));
+}
+
// Note: AnswerCurrentQuestionWithResourceRecord can call a user callback, which may change the record list and/or question list.
// Any code walking either list must use the m->CurrentQuestion (and possibly m->CurrentRecord) mechanism to protect against this.
// In fact, to enforce this, the routine will *only* answer the question currently pointed to by m->CurrentQuestion,
// which will be auto-advanced (possibly to NULL) if the client callback cancels the question.
mDNSexport void AnswerCurrentQuestionWithResourceRecord(mDNS *const m, CacheRecord *const rr, const QC_result AddRecord)
- {
- DNSQuestion *const q = m->CurrentQuestion;
- mDNSBool followcname = FollowCNAME(q, &rr->resrec, AddRecord);
-
- verbosedebugf("AnswerCurrentQuestionWithResourceRecord:%4lu %s TTL %d %s",
- q->CurrentAnswers, AddRecord ? "Add" : "Rmv", rr->resrec.rroriginalttl, CRDisplayString(m, rr));
-
- // Normally we don't send out the unicast query if we have answered using our local only auth records e.g., /etc/hosts.
- // But if the query for "A" record has a local answer but query for "AAAA" record has no local answer, we might
- // send the AAAA query out which will come back with CNAME and will also answer the "A" query. To prevent that,
- // we check to see if that query already has a unique local answer.
- if (q->LOAddressAnswers)
- {
- LogInfo("AnswerCurrentQuestionWithResourceRecord: Question %p %##s (%s) not answering with record %s due to "
- "LOAddressAnswers %d", q, q->qname.c, DNSTypeName(q->qtype), ARDisplayString(m, rr),
- q->LOAddressAnswers);
- return;
- }
-
- if (QuerySuppressed(q))
- {
- // If the query is suppressed, then we don't want to answer from the cache. But if this query is
- // supposed to time out, we still want to callback the clients. We do this only for TimeoutQuestions
- // that are timing out, which we know are answered with Negative cache record when timing out.
- if (!q->TimeoutQuestion || rr->resrec.RecordType != kDNSRecordTypePacketNegative || (m->timenow - q->StopTime < 0))
- return;
- }
-
- // Note: Use caution here. In the case of records with rr->DelayDelivery set, AnswerCurrentQuestionWithResourceRecord(... mDNStrue)
- // may be called twice, once when the record is received, and again when it's time to notify local clients.
- // If any counters or similar are added here, care must be taken to ensure that they are not double-incremented by this.
-
- rr->LastUsed = m->timenow;
- if (AddRecord == QC_add && !q->DuplicateOf && rr->CRActiveQuestion != q)
- {
- if (!rr->CRActiveQuestion) m->rrcache_active++; // If not previously active, increment rrcache_active count
- debugf("AnswerCurrentQuestionWithResourceRecord: Updating CRActiveQuestion from %p to %p for cache record %s, CurrentAnswer %d",
- rr->CRActiveQuestion, q, CRDisplayString(m,rr), q->CurrentAnswers);
- rr->CRActiveQuestion = q; // We know q is non-null
- SetNextCacheCheckTimeForRecord(m, rr);
- }
-
- // If this is:
- // (a) a no-cache add, where we've already done at least one 'QM' query, or
- // (b) a normal add, where we have at least one unique-type answer,
- // then there's no need to keep polling the network.
- // (If we have an answer in the cache, then we'll automatically ask again in time to stop it expiring.)
- // We do this for mDNS questions and uDNS one-shot questions, but not for
- // uDNS LongLived questions, because that would mess up our LLQ lease renewal timing.
- if ((AddRecord == QC_addnocache && !q->RequestUnicast) ||
- (AddRecord == QC_add && (q->ExpectUnique || (rr->resrec.RecordType & kDNSRecordTypePacketUniqueMask))))
- if (ActiveQuestion(q) && (mDNSOpaque16IsZero(q->TargetQID) || !q->LongLived))
- {
- q->LastQTime = m->timenow;
- q->LastQTxTime = m->timenow;
- q->RecentAnswerPkts = 0;
- q->ThisQInterval = MaxQuestionInterval;
- q->RequestUnicast = mDNSfalse;
- debugf("AnswerCurrentQuestionWithResourceRecord: Set MaxQuestionInterval for %##s (%s)", q->qname.c, DNSTypeName(q->qtype));
- }
-
- if (rr->DelayDelivery) return; // We'll come back later when CacheRecordDeferredAdd() calls us
-
- // Only deliver negative answers if client has explicitly requested them
- if (rr->resrec.RecordType == kDNSRecordTypePacketNegative || (q->qtype != kDNSType_NSEC && RRAssertsNonexistence(&rr->resrec, q->qtype)))
- if (!AddRecord || !q->ReturnIntermed) return;
-
- // For CNAME results to non-CNAME questions, only inform the client if they explicitly requested that
- if (q->QuestionCallback && !q->NoAnswer && (!followcname || q->ReturnIntermed))
- {
- mDNS_DropLockBeforeCallback(); // Allow client (and us) to legally make mDNS API calls
- if (q->qtype != kDNSType_NSEC && RRAssertsNonexistence(&rr->resrec, q->qtype))
- {
- CacheRecord neg;
- MakeNegativeCacheRecord(m, &neg, &q->qname, q->qnamehash, q->qtype, q->qclass, 1, rr->resrec.InterfaceID, q->qDNSServer);
- q->QuestionCallback(m, q, &neg.resrec, AddRecord);
- }
- else
- q->QuestionCallback(m, q, &rr->resrec, AddRecord);
- mDNS_ReclaimLockAfterCallback(); // Decrement mDNS_reentrancy to block mDNS API calls again
- }
- // Note: Proceed with caution here because client callback function is allowed to do anything,
- // including starting/stopping queries, registering/deregistering records, etc.
-
- if (followcname && m->CurrentQuestion == q)
- AnswerQuestionByFollowingCNAME(m, q, &rr->resrec);
- }
-
-// New Questions are answered through AnswerNewQuestion. But there may not have been any
-// matching cache records for the questions when it is called. There are two possibilities.
-//
-// 1) There are no cache records
-// 2) There are cache records but the DNSServers between question and cache record don't match.
-//
-// In the case of (1), where there are no cache records and later we add them when we get a response,
-// CacheRecordAdd/CacheRecordDeferredAdd will take care of adding the cache and delivering the ADD
-// events to the application. If we already have a cache entry, then no ADD events are delivered
-// unless the RDATA has changed
-//
-// In the case of (2) where we had the cache records and did not answer because of the DNSServer mismatch,
-// we need to answer them whenever we change the DNSServer. But we can't do it at the instant the DNSServer
-// changes because when we do the callback, the question can get deleted and the calling function would not
-// know how to handle it. So, we run this function from mDNS_Execute to handle DNSServer changes on the
-// question
-
-mDNSlocal void AnswerQuestionsForDNSServerChanges(mDNS *const m)
- {
- DNSQuestion *q;
- DNSQuestion *qnext;
- CacheRecord *rr;
- mDNSu32 slot;
- CacheGroup *cg;
-
- if (m->CurrentQuestion)
- LogMsg("AnswerQuestionsForDNSServerChanges: ERROR m->CurrentQuestion already set: %##s (%s)",
- m->CurrentQuestion->qname.c, DNSTypeName(m->CurrentQuestion->qtype));
-
- for (q = m->Questions; q && q != m->NewQuestions; q = qnext)
- {
- qnext = q->next;
-
- // multicast or DNSServers did not change.
- if (mDNSOpaque16IsZero(q->TargetQID)) continue;
- if (!q->deliverAddEvents) continue;
-
- // We are going to look through the cache for this question since it changed
- // its DNSserver last time. Reset it so that we don't call them again. Calling
- // them again will deliver duplicate events to the application
- q->deliverAddEvents = mDNSfalse;
- if (QuerySuppressed(q)) continue;
- m->CurrentQuestion = q;
- slot = HashSlot(&q->qname);
- cg = CacheGroupForName(m, slot, q->qnamehash, &q->qname);
- for (rr = cg ? cg->members : mDNSNULL; rr; rr=rr->next)
- {
- if (SameNameRecordAnswersQuestion(&rr->resrec, q))
- {
- LogInfo("AnswerQuestionsForDNSServerChanges: Calling AnswerCurrentQuestionWithResourceRecord for question %p %##s using resource record %s",
- q, q->qname.c, CRDisplayString(m, rr));
- // When this question penalizes a DNS server and has no more DNS servers to pick, we normally
- // deliver a negative cache response and suspend the question for 60 seconds (see uDNS_CheckCurrentQuestion).
- // But sometimes we may already find the negative cache entry and deliver that here as the process
- // of changing DNS servers. When the cache entry is about to expire, we will resend the question and
- // that time, we need to make sure that we have a valid DNS server. Otherwise, we will deliver
- // a negative cache response without trying the server.
- if (!q->qDNSServer && !q->DuplicateOf && rr->resrec.RecordType == kDNSRecordTypePacketNegative)
- {
- DNSQuestion *qptr;
- SetValidDNSServers(m, q);
- q->qDNSServer = GetServerForQuestion(m, q);
- for (qptr = q->next ; qptr; qptr = qptr->next)
- if (qptr->DuplicateOf == q) { qptr->validDNSServers = q->validDNSServers; qptr->qDNSServer = q->qDNSServer; }
- }
- q->CurrentAnswers++;
- if (rr->resrec.rdlength > SmallRecordLimit) q->LargeAnswers++;
- if (rr->resrec.RecordType & kDNSRecordTypePacketUniqueMask) q->UniqueAnswers++;
- AnswerCurrentQuestionWithResourceRecord(m, rr, QC_add);
- if (m->CurrentQuestion != q) break; // If callback deleted q, then we're finished here
- }
- }
- }
- m->CurrentQuestion = mDNSNULL;
- }
+{
+ DNSQuestion *const q = m->CurrentQuestion;
+ mDNSBool followcname = FollowCNAME(q, &rr->resrec, AddRecord);
+
+ verbosedebugf("AnswerCurrentQuestionWithResourceRecord:%4lu %s TTL %d %s",
+ q->CurrentAnswers, AddRecord ? "Add" : "Rmv", rr->resrec.rroriginalttl, CRDisplayString(m, rr));
+
+ // When the response for the question was validated, the entire rrset was validated. If we deliver
+ // a RMV for a single record in the rrset, we invalidate the response. If we deliver another add
+ // in the future, we will do the revalidation again.
+ //
+ // Also, if we deliver an ADD for a negative cache record and it has no NSEC/NSEC3, the ValidationStatus needs
+ // to be reset. This happens normally when we deliver a "secure" negative response followed by an insecure
+ // negative response which can happen e.g., when disconnecting from network that leads to a negative response
+ // due to no DNS servers. As we don't deliver RMVs for negative responses that were delivered before, we need
+ // to do it on the next ADD of a negative cache record. This ADD could be the result of a timeout, no DNS servers
+ // etc. in which case we need to reset the state to make sure we don't deliver them as secure. If this is
+ // a real negative response, we would reset the state here and validate the results at the end of this function.
+ // or the real response again if we purge the cache.
+ if (q->ValidationRequired && ((AddRecord == QC_rmv) ||
+ (rr->resrec.RecordType == kDNSRecordTypePacketNegative && (AddRecord == QC_add))))
+ {
+ q->ValidationStatus = 0;
+ q->ValidationState = DNSSECValRequired;
+ }
+
+ // Normally we don't send out the unicast query if we have answered using our local only auth records e.g., /etc/hosts.
+ // But if the query for "A" record has a local answer but query for "AAAA" record has no local answer, we might
+ // send the AAAA query out which will come back with CNAME and will also answer the "A" query. To prevent that,
+ // we check to see if that query already has a unique local answer.
+ if (q->LOAddressAnswers)
+ {
+ LogInfo("AnswerCurrentQuestionWithResourceRecord: Question %p %##s (%s) not answering with record %s due to "
+ "LOAddressAnswers %d", q, q->qname.c, DNSTypeName(q->qtype), ARDisplayString(m, rr),
+ q->LOAddressAnswers);
+ return;
+ }
+
+ if (QuerySuppressed(q))
+ {
+ // If the query is suppressed, then we don't want to answer from the cache. But if this query is
+ // supposed to time out, we still want to callback the clients. We do this only for TimeoutQuestions
+ // that are timing out, which we know are answered with negative cache record when timing out.
+ if (!q->TimeoutQuestion || rr->resrec.RecordType != kDNSRecordTypePacketNegative || (m->timenow - q->StopTime < 0))
+ return;
+ }
+
+ // Note: Use caution here. In the case of records with rr->DelayDelivery set, AnswerCurrentQuestionWithResourceRecord(... mDNStrue)
+ // may be called twice, once when the record is received, and again when it's time to notify local clients.
+ // If any counters or similar are added here, care must be taken to ensure that they are not double-incremented by this.
+
+ rr->LastUsed = m->timenow;
+ if (AddRecord == QC_add && !q->DuplicateOf && rr->CRActiveQuestion != q)
+ {
+ if (!rr->CRActiveQuestion) m->rrcache_active++; // If not previously active, increment rrcache_active count
+ debugf("AnswerCurrentQuestionWithResourceRecord: Updating CRActiveQuestion from %p to %p for cache record %s, CurrentAnswer %d",
+ rr->CRActiveQuestion, q, CRDisplayString(m,rr), q->CurrentAnswers);
+ rr->CRActiveQuestion = q; // We know q is non-null
+ SetNextCacheCheckTimeForRecord(m, rr);
+ }
+
+ // If this is:
+ // (a) a no-cache add, where we've already done at least one 'QM' query, or
+ // (b) a normal add, where we have at least one unique-type answer,
+ // then there's no need to keep polling the network.
+ // (If we have an answer in the cache, then we'll automatically ask again in time to stop it expiring.)
+ // We do this for mDNS questions and uDNS one-shot questions, but not for
+ // uDNS LongLived questions, because that would mess up our LLQ lease renewal timing.
+ if ((AddRecord == QC_addnocache && !q->RequestUnicast) ||
+ (AddRecord == QC_add && (q->ExpectUnique || (rr->resrec.RecordType & kDNSRecordTypePacketUniqueMask))))
+ if (ActiveQuestion(q) && (mDNSOpaque16IsZero(q->TargetQID) || !q->LongLived))
+ {
+ ResetQuestionState(m, q);
+ }
+
+ if (rr->DelayDelivery) return; // We'll come back later when CacheRecordDeferredAdd() calls us
+
+ // Only deliver negative answers if client has explicitly requested them except when we are forcing a negative response
+ // for the purpose of retrying search domains/timeout OR the question is suppressed
+ if (rr->resrec.RecordType == kDNSRecordTypePacketNegative || (q->qtype != kDNSType_NSEC && RRAssertsNonexistence(&rr->resrec, q->qtype)))
+ if (!AddRecord || (AddRecord != QC_suppressed && AddRecord != QC_forceresponse && !q->ReturnIntermed)) return;
+
+ // For CNAME results to non-CNAME questions, only inform the client if they explicitly requested that
+ if (q->QuestionCallback && !q->NoAnswer && (!followcname || q->ReturnIntermed))
+ {
+ mDNS_DropLockBeforeCallback(); // Allow client (and us) to legally make mDNS API calls
+ if (q->qtype != kDNSType_NSEC && RRAssertsNonexistence(&rr->resrec, q->qtype))
+ {
+ CacheRecord neg;
+ MakeNegativeCacheRecord(m, &neg, &q->qname, q->qnamehash, q->qtype, q->qclass, 1, rr->resrec.InterfaceID, q->qDNSServer);
+ q->QuestionCallback(m, q, &neg.resrec, AddRecord);
+ }
+ else
+ q->QuestionCallback(m, q, &rr->resrec, AddRecord);
+ mDNS_ReclaimLockAfterCallback(); // Decrement mDNS_reentrancy to block mDNS API calls again
+ }
+ // If this is an "Add" operation and this question needs validation, validate the response.
+ // In the case of negative responses, extra care should be taken. Negative cache records are
+ // used for many purposes. For example,
+ //
+ // 1) Suppressing questions (SuppressUnusable)
+ // 2) Timeout questions
+ // 3) The name does not exist
+ // 4) No DNS servers are available and we need a quick response for the application
+ //
+ // (1) and (2) are handled by "QC_add" check as AddRecord would be "QC_forceresponse" or "QC_suppressed"
+ // in that case. For (3), it is possible that we don't get nsecs back but we still need to call
+ // VerifySignature so that we can deliver the appropriate DNSSEC result. There is no point in verifying
+ // signature for (4) and hence the explicit check for q->qDNSServer.
+ //
+ if (m->CurrentQuestion == q && (AddRecord == QC_add) && !q->ValidatingResponse && q->ValidationRequired &&
+ q->ValidationState == DNSSECValRequired && q->qDNSServer)
+ {
+ q->ValidationState = DNSSECValInProgress;
+ // Treat it as callback call as that's what dnssec code expects
+ mDNS_DropLockBeforeCallback(); // Allow client (and us) to legally make mDNS API calls
+ VerifySignature(m, mDNSNULL, q);
+ mDNS_ReclaimLockAfterCallback(); // Decrement mDNS_reentrancy to block mDNS API calls again
+ return;
+ }
+
+ // Note: Proceed with caution here because client callback function is allowed to do anything,
+ // including starting/stopping queries, registering/deregistering records, etc.
+ //
+ // If we get a CNAME back while we are validating the response (i.e., CNAME for DS, DNSKEY, RRSIG),
+ // don't follow them. If it is a ValidationRequired question, wait for the CNAME to be validated
+ // first before following it
+ if (!ValidatingQuestion(q) && followcname && m->CurrentQuestion == q)
+ AnswerQuestionByFollowingCNAME(m, q, &rr->resrec);
+}
mDNSlocal void CacheRecordDeferredAdd(mDNS *const m, CacheRecord *rr)
- {
- rr->DelayDelivery = 0;
- if (m->CurrentQuestion)
- LogMsg("CacheRecordDeferredAdd ERROR m->CurrentQuestion already set: %##s (%s)",
- m->CurrentQuestion->qname.c, DNSTypeName(m->CurrentQuestion->qtype));
- m->CurrentQuestion = m->Questions;
- while (m->CurrentQuestion && m->CurrentQuestion != m->NewQuestions)
- {
- DNSQuestion *q = m->CurrentQuestion;
- if (ResourceRecordAnswersQuestion(&rr->resrec, q))
- AnswerCurrentQuestionWithResourceRecord(m, rr, QC_add);
- if (m->CurrentQuestion == q) // If m->CurrentQuestion was not auto-advanced, do it ourselves now
- m->CurrentQuestion = q->next;
- }
- m->CurrentQuestion = mDNSNULL;
- }
-
-mDNSlocal mDNSs32 CheckForSoonToExpireRecords(mDNS *const m, const domainname *const name, const mDNSu32 namehash, const mDNSu32 slot)
- {
- const mDNSs32 threshhold = m->timenow + mDNSPlatformOneSecond; // See if there are any records expiring within one second
- const mDNSs32 start = m->timenow - 0x10000000;
- mDNSs32 delay = start;
- CacheGroup *cg = CacheGroupForName(m, slot, namehash, name);
- const CacheRecord *rr;
- for (rr = cg ? cg->members : mDNSNULL; rr; rr=rr->next)
- if (threshhold - RRExpireTime(rr) >= 0) // If we have records about to expire within a second
- if (delay - RRExpireTime(rr) < 0) // then delay until after they've been deleted
- delay = RRExpireTime(rr);
- if (delay - start > 0) return(NonZeroTime(delay));
- else return(0);
- }
+{
+ rr->DelayDelivery = 0;
+ if (m->CurrentQuestion)
+ LogMsg("CacheRecordDeferredAdd ERROR m->CurrentQuestion already set: %##s (%s)",
+ m->CurrentQuestion->qname.c, DNSTypeName(m->CurrentQuestion->qtype));
+ m->CurrentQuestion = m->Questions;
+ while (m->CurrentQuestion && m->CurrentQuestion != m->NewQuestions)
+ {
+ DNSQuestion *q = m->CurrentQuestion;
+ if (ResourceRecordAnswersQuestion(&rr->resrec, q))
+ AnswerCurrentQuestionWithResourceRecord(m, rr, QC_add);
+ if (m->CurrentQuestion == q) // If m->CurrentQuestion was not auto-advanced, do it ourselves now
+ m->CurrentQuestion = q->next;
+ }
+ m->CurrentQuestion = mDNSNULL;
+}
+
+mDNSlocal mDNSs32 CheckForSoonToExpireRecords(mDNS *const m, const domainname *const name, const mDNSu32 namehash, const mDNSu32 slot, mDNSBool *purge)
+{
+ const mDNSs32 threshhold = m->timenow + mDNSPlatformOneSecond; // See if there are any records expiring within one second
+ const mDNSs32 start = m->timenow - 0x10000000;
+ mDNSs32 delay = start;
+ CacheGroup *cg = CacheGroupForName(m, slot, namehash, name);
+ const CacheRecord *rr;
+
+ if (purge)
+ *purge = mDNSfalse;
+ for (rr = cg ? cg->members : mDNSNULL; rr; rr=rr->next)
+ {
+ // If there are records that will expire soon, there are cases that need delayed
+ // delivery of events:
+ //
+ // 1) A new cache entry is about to be added as a replacement. The caller needs to
+ // deliver a RMV (for the current old entry) followed by ADD (for the new entry).
+ // It needs to schedule the timer for the next cache expiry (ScheduleNextCacheCheckTime),
+ // so that the cache entry can be purged (purging causes the RMV followed by ADD)
+ //
+ // 2) A new question is about to be answered and the caller needs to know whether it's
+ // scheduling should be delayed so that the question is not answered with this record.
+ // Instead of delivering an ADD (old entry) followed by RMV (old entry) and another ADD
+ // (new entry), a single ADD can be delivered by delaying the scheduling of the question
+ // immediately.
+ //
+ // When the unicast cache record is created, it's TTL has been extended beyond its value
+ // given in the resource record (See RRAdjustTTL). If it is in the "extended" time, the
+ // cache is already expired and we set "purge" to indicate that. When "purge" is set, the
+ // return value of the function should be ignored by the callers.
+ //
+ // Note: For case (1), "purge" argument is NULL and hence the following checks are skipped.
+ // It is okay to skip in that case because the cache records have been set to expire almost
+ // immediately and the extended time does not apply.
+ //
+ // Also, if there is already an active question we don't try to optimize as purging the cache
+ // would end up delivering RMV for the active question and hence we avoid that.
+
+ if (purge && !rr->resrec.InterfaceID && !rr->CRActiveQuestion && rr->resrec.rroriginalttl)
+ {
+ mDNSu32 uTTL = RRUnadjustedTTL(rr->resrec.rroriginalttl);
+ if (m->timenow - (rr->TimeRcvd + ((mDNSs32)uTTL * mDNSPlatformOneSecond)) >= 0)
+ {
+ LogInfo("CheckForSoonToExpireRecords: %s: rroriginalttl %u, unadjustedTTL %u, currentTTL %u",
+ CRDisplayString(m, rr), rr->resrec.rroriginalttl, uTTL, (m->timenow - rr->TimeRcvd)/mDNSPlatformOneSecond);
+ *purge = mDNStrue;
+ continue;
+ }
+ }
+ if (threshhold - RRExpireTime(rr) >= 0) // If we have records about to expire within a second
+ {
+ if (delay - RRExpireTime(rr) < 0) // then delay until after they've been deleted
+ delay = RRExpireTime(rr);
+ }
+ }
+ if (delay - start > 0)
+ return(NonZeroTime(delay));
+ else
+ return(0);
+}
// CacheRecordAdd is only called from CreateNewCacheEntry, *never* directly as a result of a client API call.
// If new questions are created as a result of invoking client callbacks, they will be added to
// which may change the record list and/or question list.
// Any code walking either list must use the CurrentQuestion and/or CurrentRecord mechanism to protect against this.
mDNSlocal void CacheRecordAdd(mDNS *const m, CacheRecord *rr)
- {
- DNSQuestion *q;
-
- // We stop when we get to NewQuestions -- if we increment their CurrentAnswers/LargeAnswers/UniqueAnswers
- // counters here we'll end up double-incrementing them when we do it again in AnswerNewQuestion().
- for (q = m->Questions; q && q != m->NewQuestions; q=q->next)
- {
- if (ResourceRecordAnswersQuestion(&rr->resrec, q))
- {
- // If this question is one that's actively sending queries, and it's received ten answers within one
- // second of sending the last query packet, then that indicates some radical network topology change,
- // so reset its exponential backoff back to the start. We must be at least at the eight-second interval
- // to do this. If we're at the four-second interval, or less, there's not much benefit accelerating
- // because we will anyway send another query within a few seconds. The first reset query is sent out
- // randomized over the next four seconds to reduce possible synchronization between machines.
- if (q->LastAnswerPktNum != m->PktNum)
- {
- q->LastAnswerPktNum = m->PktNum;
- if (mDNSOpaque16IsZero(q->TargetQID) && ActiveQuestion(q) && ++q->RecentAnswerPkts >= 10 &&
- q->ThisQInterval > InitialQuestionInterval * QuestionIntervalStep3 && m->timenow - q->LastQTxTime < mDNSPlatformOneSecond)
- {
- LogMsg("CacheRecordAdd: %##s (%s) got immediate answer burst (%d); restarting exponential backoff sequence (%d)",
- q->qname.c, DNSTypeName(q->qtype), q->RecentAnswerPkts, q->ThisQInterval);
- q->LastQTime = m->timenow - InitialQuestionInterval + (mDNSs32)mDNSRandom((mDNSu32)mDNSPlatformOneSecond*4);
- q->ThisQInterval = InitialQuestionInterval;
- SetNextQueryTime(m,q);
- }
- }
- verbosedebugf("CacheRecordAdd %p %##s (%s) %lu %#a:%d question %p", rr, rr->resrec.name->c,
- DNSTypeName(rr->resrec.rrtype), rr->resrec.rroriginalttl, rr->resrec.rDNSServer ?
- &rr->resrec.rDNSServer->addr : mDNSNULL, mDNSVal16(rr->resrec.rDNSServer ?
- rr->resrec.rDNSServer->port : zeroIPPort), q);
- q->CurrentAnswers++;
- q->unansweredQueries = 0;
- if (rr->resrec.rdlength > SmallRecordLimit) q->LargeAnswers++;
- if (rr->resrec.RecordType & kDNSRecordTypePacketUniqueMask) q->UniqueAnswers++;
- if (q->CurrentAnswers > 4000)
- {
- static int msgcount = 0;
- if (msgcount++ < 10)
- LogMsg("CacheRecordAdd: %##s (%s) has %d answers; shedding records to resist DOS attack",
- q->qname.c, DNSTypeName(q->qtype), q->CurrentAnswers);
- rr->resrec.rroriginalttl = 0;
- rr->UnansweredQueries = MaxUnansweredQueries;
- }
- }
- }
-
- if (!rr->DelayDelivery)
- {
- if (m->CurrentQuestion)
- LogMsg("CacheRecordAdd ERROR m->CurrentQuestion already set: %##s (%s)", m->CurrentQuestion->qname.c, DNSTypeName(m->CurrentQuestion->qtype));
- m->CurrentQuestion = m->Questions;
- while (m->CurrentQuestion && m->CurrentQuestion != m->NewQuestions)
- {
- q = m->CurrentQuestion;
- if (ResourceRecordAnswersQuestion(&rr->resrec, q))
- AnswerCurrentQuestionWithResourceRecord(m, rr, QC_add);
- if (m->CurrentQuestion == q) // If m->CurrentQuestion was not auto-advanced, do it ourselves now
- m->CurrentQuestion = q->next;
- }
- m->CurrentQuestion = mDNSNULL;
- }
-
- SetNextCacheCheckTimeForRecord(m, rr);
- }
+{
+ DNSQuestion *q;
+
+ // We stop when we get to NewQuestions -- if we increment their CurrentAnswers/LargeAnswers/UniqueAnswers
+ // counters here we'll end up double-incrementing them when we do it again in AnswerNewQuestion().
+ for (q = m->Questions; q && q != m->NewQuestions; q=q->next)
+ {
+ if (ResourceRecordAnswersQuestion(&rr->resrec, q))
+ {
+ // If this question is one that's actively sending queries, and it's received ten answers within one
+ // second of sending the last query packet, then that indicates some radical network topology change,
+ // so reset its exponential backoff back to the start. We must be at least at the eight-second interval
+ // to do this. If we're at the four-second interval, or less, there's not much benefit accelerating
+ // because we will anyway send another query within a few seconds. The first reset query is sent out
+ // randomized over the next four seconds to reduce possible synchronization between machines.
+ if (q->LastAnswerPktNum != m->PktNum)
+ {
+ q->LastAnswerPktNum = m->PktNum;
+ if (mDNSOpaque16IsZero(q->TargetQID) && ActiveQuestion(q) && ++q->RecentAnswerPkts >= 10 &&
+ q->ThisQInterval > InitialQuestionInterval * QuestionIntervalStep3 && m->timenow - q->LastQTxTime < mDNSPlatformOneSecond)
+ {
+ LogMsg("CacheRecordAdd: %##s (%s) got immediate answer burst (%d); restarting exponential backoff sequence (%d)",
+ q->qname.c, DNSTypeName(q->qtype), q->RecentAnswerPkts, q->ThisQInterval);
+ q->LastQTime = m->timenow - InitialQuestionInterval + (mDNSs32)mDNSRandom((mDNSu32)mDNSPlatformOneSecond*4);
+ q->ThisQInterval = InitialQuestionInterval;
+ SetNextQueryTime(m,q);
+ }
+ }
+ verbosedebugf("CacheRecordAdd %p %##s (%s) %lu %#a:%d question %p", rr, rr->resrec.name->c,
+ DNSTypeName(rr->resrec.rrtype), rr->resrec.rroriginalttl, rr->resrec.rDNSServer ?
+ &rr->resrec.rDNSServer->addr : mDNSNULL, mDNSVal16(rr->resrec.rDNSServer ?
+ rr->resrec.rDNSServer->port : zeroIPPort), q);
+ q->CurrentAnswers++;
+
+ q->unansweredQueries = 0;
+ if (rr->resrec.rdlength > SmallRecordLimit) q->LargeAnswers++;
+ if (rr->resrec.RecordType & kDNSRecordTypePacketUniqueMask) q->UniqueAnswers++;
+ if (q->CurrentAnswers > 4000)
+ {
+ static int msgcount = 0;
+ if (msgcount++ < 10)
+ LogMsg("CacheRecordAdd: %##s (%s) has %d answers; shedding records to resist DOS attack",
+ q->qname.c, DNSTypeName(q->qtype), q->CurrentAnswers);
+ rr->resrec.rroriginalttl = 0;
+ rr->UnansweredQueries = MaxUnansweredQueries;
+ }
+ }
+ }
+
+ if (!rr->DelayDelivery)
+ {
+ if (m->CurrentQuestion)
+ LogMsg("CacheRecordAdd ERROR m->CurrentQuestion already set: %##s (%s)", m->CurrentQuestion->qname.c, DNSTypeName(m->CurrentQuestion->qtype));
+ m->CurrentQuestion = m->Questions;
+ while (m->CurrentQuestion && m->CurrentQuestion != m->NewQuestions)
+ {
+ q = m->CurrentQuestion;
+ if (ResourceRecordAnswersQuestion(&rr->resrec, q))
+ AnswerCurrentQuestionWithResourceRecord(m, rr, QC_add);
+ if (m->CurrentQuestion == q) // If m->CurrentQuestion was not auto-advanced, do it ourselves now
+ m->CurrentQuestion = q->next;
+ }
+ m->CurrentQuestion = mDNSNULL;
+ }
+
+ SetNextCacheCheckTimeForRecord(m, rr);
+}
// NoCacheAnswer is only called from mDNSCoreReceiveResponse, *never* directly as a result of a client API call.
// If new questions are created as a result of invoking client callbacks, they will be added to
// which may change the record list and/or question list.
// Any code walking either list must use the CurrentQuestion and/or CurrentRecord mechanism to protect against this.
mDNSlocal void NoCacheAnswer(mDNS *const m, CacheRecord *rr)
- {
- LogMsg("No cache space: Delivering non-cached result for %##s", m->rec.r.resrec.name->c);
- if (m->CurrentQuestion)
- LogMsg("NoCacheAnswer ERROR m->CurrentQuestion already set: %##s (%s)", m->CurrentQuestion->qname.c, DNSTypeName(m->CurrentQuestion->qtype));
- m->CurrentQuestion = m->Questions;
- // We do this for *all* questions, not stopping when we get to m->NewQuestions,
- // since we're not caching the record and we'll get no opportunity to do this later
- while (m->CurrentQuestion)
- {
- DNSQuestion *q = m->CurrentQuestion;
- if (ResourceRecordAnswersQuestion(&rr->resrec, q))
- AnswerCurrentQuestionWithResourceRecord(m, rr, QC_addnocache); // QC_addnocache means "don't expect remove events for this"
- if (m->CurrentQuestion == q) // If m->CurrentQuestion was not auto-advanced, do it ourselves now
- m->CurrentQuestion = q->next;
- }
- m->CurrentQuestion = mDNSNULL;
- }
+{
+ LogMsg("No cache space: Delivering non-cached result for %##s", m->rec.r.resrec.name->c);
+ if (m->CurrentQuestion)
+ LogMsg("NoCacheAnswer ERROR m->CurrentQuestion already set: %##s (%s)", m->CurrentQuestion->qname.c, DNSTypeName(m->CurrentQuestion->qtype));
+ m->CurrentQuestion = m->Questions;
+ // We do this for *all* questions, not stopping when we get to m->NewQuestions,
+ // since we're not caching the record and we'll get no opportunity to do this later
+ while (m->CurrentQuestion)
+ {
+ DNSQuestion *q = m->CurrentQuestion;
+ if (ResourceRecordAnswersQuestion(&rr->resrec, q))
+ AnswerCurrentQuestionWithResourceRecord(m, rr, QC_addnocache); // QC_addnocache means "don't expect remove events for this"
+ if (m->CurrentQuestion == q) // If m->CurrentQuestion was not auto-advanced, do it ourselves now
+ m->CurrentQuestion = q->next;
+ }
+ m->CurrentQuestion = mDNSNULL;
+}
// CacheRecordRmv is only called from CheckCacheExpiration, which is called from mDNS_Execute.
// Note that CacheRecordRmv is *only* called for records that are referenced by at least one active question.
// which may change the record list and/or question list.
// Any code walking either list must use the CurrentQuestion and/or CurrentRecord mechanism to protect against this.
mDNSlocal void CacheRecordRmv(mDNS *const m, CacheRecord *rr)
- {
- if (m->CurrentQuestion)
- LogMsg("CacheRecordRmv ERROR m->CurrentQuestion already set: %##s (%s)",
- m->CurrentQuestion->qname.c, DNSTypeName(m->CurrentQuestion->qtype));
- m->CurrentQuestion = m->Questions;
-
- // We stop when we get to NewQuestions -- for new questions their CurrentAnswers/LargeAnswers/UniqueAnswers counters
- // will all still be zero because we haven't yet gone through the cache counting how many answers we have for them.
- while (m->CurrentQuestion && m->CurrentQuestion != m->NewQuestions)
- {
- DNSQuestion *q = m->CurrentQuestion;
- // When a question enters suppressed state, we generate RMV events and generate a negative
- // response. A cache may be present that answers this question e.g., cache entry generated
- // before the question became suppressed. We need to skip the suppressed questions here as
- // the RMV event has already been generated.
- if (!QuerySuppressed(q) && ResourceRecordAnswersQuestion(&rr->resrec, q))
- {
- verbosedebugf("CacheRecordRmv %p %s", rr, CRDisplayString(m, rr));
- q->FlappingInterface1 = mDNSNULL;
- q->FlappingInterface2 = mDNSNULL;
-
- // When a question changes DNS server, it is marked with deliverAddEvents if we find any
- // cache entry corresponding to the new DNS server. Before we deliver the ADD event, the
- // cache entry may be removed in which case CurrentAnswers can be zero.
- if (q->deliverAddEvents && !q->CurrentAnswers)
- {
- LogInfo("CacheRecordRmv: Question %p %##s (%s) deliverAddEvents set, DNSServer %#a:%d",
- q, q->qname.c, DNSTypeName(q->qtype), q->qDNSServer ? &q->qDNSServer->addr : mDNSNULL,
- mDNSVal16(q->qDNSServer ? q->qDNSServer->port : zeroIPPort));
- m->CurrentQuestion = q->next;
- continue;
- }
- if (q->CurrentAnswers == 0)
- LogMsg("CacheRecordRmv ERROR!!: How can CurrentAnswers already be zero for %p %##s (%s) DNSServer %#a:%d",
- q, q->qname.c, DNSTypeName(q->qtype), q->qDNSServer ? &q->qDNSServer->addr : mDNSNULL,
- mDNSVal16(q->qDNSServer ? q->qDNSServer->port : zeroIPPort));
- else
- {
- q->CurrentAnswers--;
- if (rr->resrec.rdlength > SmallRecordLimit) q->LargeAnswers--;
- if (rr->resrec.RecordType & kDNSRecordTypePacketUniqueMask) q->UniqueAnswers--;
- }
- if (rr->resrec.rdata->MaxRDLength) // Never generate "remove" events for negative results
- {
- if (q->CurrentAnswers == 0)
- {
- LogInfo("CacheRecordRmv: Last answer for %##s (%s) expired from cache; will reconfirm antecedents",
- q->qname.c, DNSTypeName(q->qtype));
- ReconfirmAntecedents(m, &q->qname, q->qnamehash, 0);
- }
- AnswerCurrentQuestionWithResourceRecord(m, rr, QC_rmv);
- }
- }
- if (m->CurrentQuestion == q) // If m->CurrentQuestion was not auto-advanced, do it ourselves now
- m->CurrentQuestion = q->next;
- }
- m->CurrentQuestion = mDNSNULL;
- }
+{
+ if (m->CurrentQuestion)
+ LogMsg("CacheRecordRmv ERROR m->CurrentQuestion already set: %##s (%s)",
+ m->CurrentQuestion->qname.c, DNSTypeName(m->CurrentQuestion->qtype));
+ m->CurrentQuestion = m->Questions;
+
+ // We stop when we get to NewQuestions -- for new questions their CurrentAnswers/LargeAnswers/UniqueAnswers counters
+ // will all still be zero because we haven't yet gone through the cache counting how many answers we have for them.
+ while (m->CurrentQuestion && m->CurrentQuestion != m->NewQuestions)
+ {
+ DNSQuestion *q = m->CurrentQuestion;
+ // When a question enters suppressed state, we generate RMV events and generate a negative
+ // response. A cache may be present that answers this question e.g., cache entry generated
+ // before the question became suppressed. We need to skip the suppressed questions here as
+ // the RMV event has already been generated.
+ if (!QuerySuppressed(q) && ResourceRecordAnswersQuestion(&rr->resrec, q))
+ {
+ verbosedebugf("CacheRecordRmv %p %s", rr, CRDisplayString(m, rr));
+ q->FlappingInterface1 = mDNSNULL;
+ q->FlappingInterface2 = mDNSNULL;
+
+ if (q->CurrentAnswers == 0)
+ LogMsg("CacheRecordRmv ERROR!!: How can CurrentAnswers already be zero for %p %##s (%s) DNSServer %#a:%d",
+ q, q->qname.c, DNSTypeName(q->qtype), q->qDNSServer ? &q->qDNSServer->addr : mDNSNULL,
+ mDNSVal16(q->qDNSServer ? q->qDNSServer->port : zeroIPPort));
+ else
+ {
+ q->CurrentAnswers--;
+ if (rr->resrec.rdlength > SmallRecordLimit) q->LargeAnswers--;
+ if (rr->resrec.RecordType & kDNSRecordTypePacketUniqueMask) q->UniqueAnswers--;
+ }
+
+ // If we have dropped below the answer threshold for this mDNS question,
+ // restart the queries at InitialQuestionInterval.
+ if (mDNSOpaque16IsZero(q->TargetQID) && (q->BrowseThreshold > 0) && (q->CurrentAnswers < q->BrowseThreshold))
+ {
+ q->ThisQInterval = InitialQuestionInterval;
+ q->LastQTime = m->timenow - q->ThisQInterval;
+ SetNextQueryTime(m,q);
+ LogInfo("CacheRecordRmv: (%s) %##s dropped below threshold of %d answers",
+ DNSTypeName(q->qtype), q->qname.c, q->BrowseThreshold);
+ }
+ if (rr->resrec.rdata->MaxRDLength) // Never generate "remove" events for negative results
+ {
+ if (q->CurrentAnswers == 0)
+ {
+ LogInfo("CacheRecordRmv: Last answer for %##s (%s) expired from cache; will reconfirm antecedents",
+ q->qname.c, DNSTypeName(q->qtype));
+ ReconfirmAntecedents(m, &q->qname, q->qnamehash, 0);
+ }
+ AnswerCurrentQuestionWithResourceRecord(m, rr, QC_rmv);
+ }
+ }
+ if (m->CurrentQuestion == q) // If m->CurrentQuestion was not auto-advanced, do it ourselves now
+ m->CurrentQuestion = q->next;
+ }
+ m->CurrentQuestion = mDNSNULL;
+}
mDNSlocal void ReleaseCacheEntity(mDNS *const m, CacheEntity *e)
- {
+{
#if APPLE_OSX_mDNSResponder && MACOSX_MDNS_MALLOC_DEBUGGING >= 1
- unsigned int i;
- for (i=0; i<sizeof(*e); i++) ((char*)e)[i] = 0xFF;
+ unsigned int i;
+ for (i=0; i<sizeof(*e); i++) ((char*)e)[i] = 0xFF;
#endif
- e->next = m->rrcache_free;
- m->rrcache_free = e;
- m->rrcache_totalused--;
- }
+ e->next = m->rrcache_free;
+ m->rrcache_free = e;
+ m->rrcache_totalused--;
+}
mDNSlocal void ReleaseCacheGroup(mDNS *const m, CacheGroup **cp)
- {
- CacheEntity *e = (CacheEntity *)(*cp);
- //LogMsg("ReleaseCacheGroup: Releasing CacheGroup for %p, %##s", (*cp)->name->c, (*cp)->name->c);
- if ((*cp)->rrcache_tail != &(*cp)->members)
- LogMsg("ERROR: (*cp)->members == mDNSNULL but (*cp)->rrcache_tail != &(*cp)->members)");
- //if ((*cp)->name != (domainname*)((*cp)->namestorage))
- // LogMsg("ReleaseCacheGroup: %##s, %p %p", (*cp)->name->c, (*cp)->name, (domainname*)((*cp)->namestorage));
- if ((*cp)->name != (domainname*)((*cp)->namestorage)) mDNSPlatformMemFree((*cp)->name);
- (*cp)->name = mDNSNULL;
- *cp = (*cp)->next; // Cut record from list
- ReleaseCacheEntity(m, e);
- }
-
-mDNSlocal void ReleaseCacheRecord(mDNS *const m, CacheRecord *r)
- {
- //LogMsg("ReleaseCacheRecord: Releasing %s", CRDisplayString(m, r));
- if (r->resrec.rdata && r->resrec.rdata != (RData*)&r->smallrdatastorage) mDNSPlatformMemFree(r->resrec.rdata);
- r->resrec.rdata = mDNSNULL;
- ReleaseCacheEntity(m, (CacheEntity *)r);
- }
+{
+ CacheEntity *e = (CacheEntity *)(*cp);
+ //LogMsg("ReleaseCacheGroup: Releasing CacheGroup for %p, %##s", (*cp)->name->c, (*cp)->name->c);
+ if ((*cp)->rrcache_tail != &(*cp)->members)
+ LogMsg("ERROR: (*cp)->members == mDNSNULL but (*cp)->rrcache_tail != &(*cp)->members)");
+ //if ((*cp)->name != (domainname*)((*cp)->namestorage))
+ // LogMsg("ReleaseCacheGroup: %##s, %p %p", (*cp)->name->c, (*cp)->name, (domainname*)((*cp)->namestorage));
+ if ((*cp)->name != (domainname*)((*cp)->namestorage)) mDNSPlatformMemFree((*cp)->name);
+ (*cp)->name = mDNSNULL;
+ *cp = (*cp)->next; // Cut record from list
+ ReleaseCacheEntity(m, e);
+}
+
+mDNSlocal void ReleaseAdditionalCacheRecords(mDNS *const m, CacheRecord **rp)
+{
+ while (*rp)
+ {
+ CacheRecord *rr = *rp;
+ *rp = (*rp)->next; // Cut record from list
+ if (rr->resrec.rdata && rr->resrec.rdata != (RData*)&rr->smallrdatastorage)
+ {
+ mDNSPlatformMemFree(rr->resrec.rdata);
+ rr->resrec.rdata = mDNSNULL;
+ }
+ // NSEC or SOA records that are not added to the CacheGroup do not share the name
+ // of the CacheGroup.
+ if (rr->resrec.name)
+ {
+ debugf("ReleaseAdditionalCacheRecords: freeing cached record %##s (%s)", rr->resrec.name->c, DNSTypeName(rr->resrec.rrtype));
+ mDNSPlatformMemFree((void *)rr->resrec.name);
+ rr->resrec.name = mDNSNULL;
+ }
+ // Don't count the NSEC3 records used by anonymous browse/reg
+ if (!rr->resrec.InterfaceID)
+ {
+ m->rrcache_totalused_unicast -= rr->resrec.rdlength;
+ if (DNSSECRecordType(rr->resrec.rrtype))
+ BumpDNSSECStats(m, kStatsActionDecrement, kStatsTypeMemoryUsage, rr->resrec.rdlength);
+ }
+ ReleaseCacheEntity(m, (CacheEntity *)rr);
+ }
+}
+
+mDNSexport void ReleaseCacheRecord(mDNS *const m, CacheRecord *r)
+{
+ CacheGroup *cg;
+ const mDNSu32 slot = HashSlot(r->resrec.name);
+
+ //LogMsg("ReleaseCacheRecord: Releasing %s", CRDisplayString(m, r));
+ if (r->resrec.rdata && r->resrec.rdata != (RData*)&r->smallrdatastorage) mDNSPlatformMemFree(r->resrec.rdata);
+ r->resrec.rdata = mDNSNULL;
+
+ cg = CacheGroupForRecord(m, slot, &r->resrec);
+
+ if (!cg)
+ {
+ // It is okay to have this printed for NSEC/NSEC3s
+ LogInfo("ReleaseCacheRecord: ERROR!! cg NULL for %##s (%s)", r->resrec.name->c, DNSTypeName(r->resrec.rrtype));
+ }
+ // When NSEC records are not added to the cache, it is usually cached at the "nsec" list
+ // of the CacheRecord. But sometimes they may be freed without adding to the "nsec" list
+ // (which is handled below) and in that case it should be freed here.
+ if (r->resrec.name && cg && r->resrec.name != cg->name)
+ {
+ debugf("ReleaseCacheRecord: freeing %##s (%s)", r->resrec.name->c, DNSTypeName(r->resrec.rrtype));
+ mDNSPlatformMemFree((void *)r->resrec.name);
+ }
+ r->resrec.name = mDNSNULL;
+
+ if (r->resrec.AnonInfo)
+ {
+ debugf("ReleaseCacheRecord: freeing AnonInfo for %##s (%s)", r->resrec.name->c, DNSTypeName(r->resrec.rrtype));
+ FreeAnonInfo((void *)r->resrec.AnonInfo);
+ }
+ r->resrec.AnonInfo = mDNSNULL;
+
+ if (!r->resrec.InterfaceID)
+ {
+ m->rrcache_totalused_unicast -= r->resrec.rdlength;
+ if (DNSSECRecordType(r->resrec.rrtype))
+ BumpDNSSECStats(m, kStatsActionDecrement, kStatsTypeMemoryUsage, r->resrec.rdlength);
+ }
+
+ ReleaseAdditionalCacheRecords(m, &r->nsec);
+ ReleaseAdditionalCacheRecords(m, &r->soa);
+
+ ReleaseCacheEntity(m, (CacheEntity *)r);
+}
// Note: We want to be careful that we deliver all the CacheRecordRmv calls before delivering
// CacheRecordDeferredAdd calls. The in-order nature of the cache lists ensures that all
// callbacks for old records are delivered before callbacks for newer records.
mDNSlocal void CheckCacheExpiration(mDNS *const m, const mDNSu32 slot, CacheGroup *const cg)
- {
- CacheRecord **rp = &cg->members;
-
- if (m->lock_rrcache) { LogMsg("CheckCacheExpiration ERROR! Cache already locked!"); return; }
- m->lock_rrcache = 1;
-
- while (*rp)
- {
- CacheRecord *const rr = *rp;
- mDNSs32 event = RRExpireTime(rr);
- if (m->timenow - event >= 0) // If expired, delete it
- {
- *rp = rr->next; // Cut it from the list
- verbosedebugf("CheckCacheExpiration: Deleting%7d %7d %p %s",
- m->timenow - rr->TimeRcvd, rr->resrec.rroriginalttl, rr->CRActiveQuestion, CRDisplayString(m, rr));
- if (rr->CRActiveQuestion) // If this record has one or more active questions, tell them it's going away
- {
- DNSQuestion *q = rr->CRActiveQuestion;
- // When a cache record is about to expire, we expect to do four queries at 80-82%, 85-87%, 90-92% and
- // then 95-97% of the TTL. If the DNS server does not respond, then we will remove the cache entry
- // before we pick a new DNS server. As the question interval is set to MaxQuestionInterval, we may
- // not send out a query anytime soon. Hence, we need to reset the question interval. If this is
- // a normal deferred ADD case, then AnswerCurrentQuestionWithResourceRecord will reset it to
- // MaxQuestionInterval. If we have inactive questions referring to negative cache entries,
- // don't ressurect them as they will deliver duplicate "No such Record" ADD events
- if (!mDNSOpaque16IsZero(q->TargetQID) && !q->LongLived && ActiveQuestion(q))
- {
- q->ThisQInterval = InitialQuestionInterval;
- q->LastQTime = m->timenow - q->ThisQInterval;
- SetNextQueryTime(m, q);
- }
- CacheRecordRmv(m, rr);
- m->rrcache_active--;
- }
- ReleaseCacheRecord(m, rr);
- }
- else // else, not expired; see if we need to query
- {
- // If waiting to delay delivery, do nothing until then
- if (rr->DelayDelivery && rr->DelayDelivery - m->timenow > 0)
- event = rr->DelayDelivery;
- else
- {
- if (rr->DelayDelivery) CacheRecordDeferredAdd(m, rr);
- if (rr->CRActiveQuestion && rr->UnansweredQueries < MaxUnansweredQueries)
- {
- if (m->timenow - rr->NextRequiredQuery < 0) // If not yet time for next query
- event = NextCacheCheckEvent(rr); // then just record when we want the next query
- else // else trigger our question to go out now
- {
- // Set NextScheduledQuery to timenow so that SendQueries() will run.
- // SendQueries() will see that we have records close to expiration, and send FEQs for them.
- m->NextScheduledQuery = m->timenow;
- // After sending the query we'll increment UnansweredQueries and call SetNextCacheCheckTimeForRecord(),
- // which will correctly update m->NextCacheCheck for us.
- event = m->timenow + 0x3FFFFFFF;
- }
- }
- }
- verbosedebugf("CheckCacheExpiration:%6d %5d %s",
- (event - m->timenow) / mDNSPlatformOneSecond, CacheCheckGracePeriod(rr), CRDisplayString(m, rr));
- if (m->rrcache_nextcheck[slot] - event > 0)
- m->rrcache_nextcheck[slot] = event;
- rp = &rr->next;
- }
- }
- if (cg->rrcache_tail != rp) verbosedebugf("CheckCacheExpiration: Updating CacheGroup tail from %p to %p", cg->rrcache_tail, rp);
- cg->rrcache_tail = rp;
- m->lock_rrcache = 0;
- }
+{
+ CacheRecord **rp = &cg->members;
+
+ if (m->lock_rrcache) { LogMsg("CheckCacheExpiration ERROR! Cache already locked!"); return; }
+ m->lock_rrcache = 1;
+
+ while (*rp)
+ {
+ CacheRecord *const rr = *rp;
+ mDNSs32 event = RRExpireTime(rr);
+ if (m->timenow - event >= 0) // If expired, delete it
+ {
+ *rp = rr->next; // Cut it from the list
+
+ verbosedebugf("CheckCacheExpiration: Deleting%7d %7d %p %s",
+ m->timenow - rr->TimeRcvd, rr->resrec.rroriginalttl, rr->CRActiveQuestion, CRDisplayString(m, rr));
+ if (rr->CRActiveQuestion) // If this record has one or more active questions, tell them it's going away
+ {
+ DNSQuestion *q = rr->CRActiveQuestion;
+ // When a cache record is about to expire, we expect to do four queries at 80-82%, 85-87%, 90-92% and
+ // then 95-97% of the TTL. If the DNS server does not respond, then we will remove the cache entry
+ // before we pick a new DNS server. As the question interval is set to MaxQuestionInterval, we may
+ // not send out a query anytime soon. Hence, we need to reset the question interval. If this is
+ // a normal deferred ADD case, then AnswerCurrentQuestionWithResourceRecord will reset it to
+ // MaxQuestionInterval. If we have inactive questions referring to negative cache entries,
+ // don't ressurect them as they will deliver duplicate "No such Record" ADD events
+ if (!mDNSOpaque16IsZero(q->TargetQID) && !q->LongLived && ActiveQuestion(q))
+ {
+ q->ThisQInterval = InitialQuestionInterval;
+ q->LastQTime = m->timenow - q->ThisQInterval;
+ SetNextQueryTime(m, q);
+ }
+ CacheRecordRmv(m, rr);
+ m->rrcache_active--;
+ }
+ ReleaseCacheRecord(m, rr);
+ }
+ else // else, not expired; see if we need to query
+ {
+ // If waiting to delay delivery, do nothing until then
+ if (rr->DelayDelivery && rr->DelayDelivery - m->timenow > 0)
+ event = rr->DelayDelivery;
+ else
+ {
+ if (rr->DelayDelivery) CacheRecordDeferredAdd(m, rr);
+ if (rr->CRActiveQuestion && rr->UnansweredQueries < MaxUnansweredQueries)
+ {
+ if (m->timenow - rr->NextRequiredQuery < 0) // If not yet time for next query
+ event = NextCacheCheckEvent(rr); // then just record when we want the next query
+ else // else trigger our question to go out now
+ {
+ // Set NextScheduledQuery to timenow so that SendQueries() will run.
+ // SendQueries() will see that we have records close to expiration, and send FEQs for them.
+ m->NextScheduledQuery = m->timenow;
+ // After sending the query we'll increment UnansweredQueries and call SetNextCacheCheckTimeForRecord(),
+ // which will correctly update m->NextCacheCheck for us.
+ event = m->timenow + 0x3FFFFFFF;
+ }
+ }
+ }
+ verbosedebugf("CheckCacheExpiration:%6d %5d %s",
+ (event - m->timenow) / mDNSPlatformOneSecond, CacheCheckGracePeriod(rr), CRDisplayString(m, rr));
+ if (m->rrcache_nextcheck[slot] - event > 0)
+ m->rrcache_nextcheck[slot] = event;
+ rp = &rr->next;
+ }
+ }
+ if (cg->rrcache_tail != rp) verbosedebugf("CheckCacheExpiration: Updating CacheGroup tail from %p to %p", cg->rrcache_tail, rp);
+ cg->rrcache_tail = rp;
+ m->lock_rrcache = 0;
+}
+
+// "LORecord" includes both LocalOnly and P2P record. This function assumes m->CurrentQuestion is pointing to "q".
+//
+// If "CheckOnly" is set to "true", the question won't be answered but just check to see if there is an answer and
+// returns true if there is an answer.
+//
+// If "CheckOnly" is set to "false", the question will be answered if there is a LocalOnly/P2P record and
+// returns true to indicate the same.
+mDNSlocal mDNSBool AnswerQuestionWithLORecord(mDNS *const m, DNSQuestion *q, mDNSBool checkOnly)
+{
+ mDNSu32 slot;
+ AuthRecord *lr;
+ AuthGroup *ag;
+
+ if (m->CurrentRecord)
+ LogMsg("AnswerQuestionWithLORecord ERROR m->CurrentRecord already set %s", ARDisplayString(m, m->CurrentRecord));
+
+ slot = AuthHashSlot(&q->qname);
+ ag = AuthGroupForName(&m->rrauth, slot, q->qnamehash, &q->qname);
+ if (ag)
+ {
+ m->CurrentRecord = ag->members;
+ while (m->CurrentRecord && m->CurrentRecord != ag->NewLocalOnlyRecords)
+ {
+ AuthRecord *rr = m->CurrentRecord;
+ m->CurrentRecord = rr->next;
+ //
+ // If the question is mDNSInterface_LocalOnly, all records local to the machine should be used
+ // to answer the query. This is handled in AnswerNewLocalOnlyQuestion.
+ //
+ // We handle mDNSInterface_Any and scoped questions here. See LocalOnlyRecordAnswersQuestion for more
+ // details on how we handle this case. For P2P we just handle "Interface_Any" questions. For LocalOnly
+ // we handle both mDNSInterface_Any and scoped questions.
+
+ if (rr->ARType == AuthRecordLocalOnly || (rr->ARType == AuthRecordP2P && q->InterfaceID == mDNSInterface_Any))
+ if (LocalOnlyRecordAnswersQuestion(rr, q))
+ {
+ if (checkOnly)
+ {
+ LogInfo("AnswerQuestionWithLORecord: question %##s (%s) answered by %s", q->qname.c, DNSTypeName(q->qtype),
+ ARDisplayString(m, rr));
+ m->CurrentRecord = mDNSNULL;
+ return mDNStrue;
+ }
+ AnswerLocalQuestionWithLocalAuthRecord(m, rr, mDNStrue);
+ if (m->CurrentQuestion != q)
+ break; // If callback deleted q, then we're finished here
+ }
+ }
+ }
+ m->CurrentRecord = mDNSNULL;
+
+ if (m->CurrentQuestion != q)
+ {
+ LogInfo("AnswerQuestionWithLORecord: Question deleted while while answering LocalOnly record answers");
+ return mDNStrue;
+ }
+
+ if (q->LOAddressAnswers)
+ {
+ LogInfo("AnswerQuestionWithLORecord: Question %p %##s (%s) answered using local auth records LOAddressAnswers %d",
+ q, q->qname.c, DNSTypeName(q->qtype), q->LOAddressAnswers);
+ return mDNStrue;
+ }
+
+ // Before we go check the cache and ship this query on the wire, we have to be sure that there are
+ // no local records that could possibly answer this question. As we did not check the NewLocalRecords, we
+ // need to just peek at them to see whether it will answer this question. If it would answer, pretend
+ // that we answered. AnswerAllLocalQuestionsWithLocalAuthRecord will answer shortly. This happens normally
+ // when we add new /etc/hosts entries and restart the question. It is a new question and also a new record.
+ if (ag)
+ {
+ lr = ag->NewLocalOnlyRecords;
+ while (lr)
+ {
+ if (UniqueLocalOnlyRecord(lr) && LocalOnlyRecordAnswersQuestion(lr, q))
+ {
+ LogInfo("AnswerQuestionWithLORecord: Question %p %##s (%s) will be answered using new local auth records "
+ " LOAddressAnswers %d", q, q->qname.c, DNSTypeName(q->qtype), q->LOAddressAnswers);
+ return mDNStrue;
+ }
+ lr = lr->next;
+ }
+ }
+ return mDNSfalse;
+}
+
+// Today, we suppress questions (not send them on the wire) for several reasons e.g.,
+// AAAA query is suppressed because no IPv6 capability or PID is not allowed to make
+// DNS requests. We need to temporarily suspend the suppress status so that we can
+// deliver a negative response (AnswerCurrentQuestionWithResourceRecord does not answer
+// suppressed questions) and reset it back. In the future, if there are other
+// reasons for suppressing the query, this function should be updated.
+mDNSlocal void AnswerSuppressedQuestion(mDNS *const m, DNSQuestion *q)
+{
+ mDNSBool SuppressQuery = q->SuppressQuery;
+ mDNSBool DisallowPID = q->DisallowPID;
+
+ // make sure that QuerySuppressed() returns false
+ q->SuppressQuery = mDNSfalse;
+ q->DisallowPID = mDNSfalse;
+
+ GenerateNegativeResponse(m, QC_suppressed);
+
+ q->SuppressQuery = SuppressQuery;
+ q->DisallowPID = DisallowPID;
+}
mDNSlocal void AnswerNewQuestion(mDNS *const m)
- {
- mDNSBool ShouldQueryImmediately = mDNStrue;
- DNSQuestion *const q = m->NewQuestions; // Grab the question we're going to answer
- mDNSu32 slot = HashSlot(&q->qname);
- CacheGroup *const cg = CacheGroupForName(m, slot, q->qnamehash, &q->qname);
- AuthRecord *lr;
- AuthGroup *ag;
- mDNSBool AnsweredFromCache = mDNSfalse;
-
- verbosedebugf("AnswerNewQuestion: Answering %##s (%s)", q->qname.c, DNSTypeName(q->qtype));
-
- if (cg) CheckCacheExpiration(m, slot, cg);
- if (m->NewQuestions != q) { LogInfo("AnswerNewQuestion: Question deleted while doing CheckCacheExpiration"); goto exit; }
- m->NewQuestions = q->next;
- // Advance NewQuestions to the next *after* calling CheckCacheExpiration, because if we advance it first
- // then CheckCacheExpiration may give this question add/remove callbacks, and it's not yet ready for that.
- //
- // Also, CheckCacheExpiration() calls CacheRecordDeferredAdd() and CacheRecordRmv(), which invoke
- // client callbacks, which may delete their own or any other question. Our mechanism for detecting
- // whether our current m->NewQuestions question got deleted by one of these callbacks is to store the
- // value of m->NewQuestions in 'q' before calling CheckCacheExpiration(), and then verify afterwards
- // that they're still the same. If m->NewQuestions has changed (because mDNS_StopQuery_internal
- // advanced it), that means the question was deleted, so we no longer need to worry about answering
- // it (and indeed 'q' is now a dangling pointer, so dereferencing it at all would be bad, and the
- // values we computed for slot and cg are now stale and relate to a question that no longer exists).
- //
- // We can't use the usual m->CurrentQuestion mechanism for this because CacheRecordDeferredAdd() and
- // CacheRecordRmv() both use that themselves when walking the list of (non-new) questions generating callbacks.
- // Fortunately mDNS_StopQuery_internal auto-advances both m->CurrentQuestion *AND* m->NewQuestions when
- // deleting a question, so luckily we have an easy alternative way of detecting if our question got deleted.
-
- if (m->lock_rrcache) LogMsg("AnswerNewQuestion ERROR! Cache already locked!");
- // This should be safe, because calling the client's question callback may cause the
- // question list to be modified, but should not ever cause the rrcache list to be modified.
- // If the client's question callback deletes the question, then m->CurrentQuestion will
- // be advanced, and we'll exit out of the loop
- m->lock_rrcache = 1;
- if (m->CurrentQuestion)
- LogMsg("AnswerNewQuestion ERROR m->CurrentQuestion already set: %##s (%s)",
- m->CurrentQuestion->qname.c, DNSTypeName(m->CurrentQuestion->qtype));
- m->CurrentQuestion = q; // Indicate which question we're answering, so we'll know if it gets deleted
-
- if (q->NoAnswer == NoAnswer_Fail)
- {
- LogMsg("AnswerNewQuestion: NoAnswer_Fail %##s (%s)", q->qname.c, DNSTypeName(q->qtype));
- MakeNegativeCacheRecord(m, &m->rec.r, &q->qname, q->qnamehash, q->qtype, q->qclass, 60, mDNSInterface_Any, q->qDNSServer);
- q->NoAnswer = NoAnswer_Normal; // Temporarily turn off answer suppression
- AnswerCurrentQuestionWithResourceRecord(m, &m->rec.r, QC_addnocache);
- // Don't touch the question if it has been stopped already
- if (m->CurrentQuestion == q) q->NoAnswer = NoAnswer_Fail; // Restore NoAnswer state
- m->rec.r.resrec.RecordType = 0; // Clear RecordType to show we're not still using it
- }
- if (m->CurrentQuestion != q) { LogInfo("AnswerNewQuestion: Question deleted while generating NoAnswer_Fail response"); goto exit; }
-
- // See if we want to tell it about LocalOnly records
- if (m->CurrentRecord)
- LogMsg("AnswerNewQuestion ERROR m->CurrentRecord already set %s", ARDisplayString(m, m->CurrentRecord));
- slot = AuthHashSlot(&q->qname);
- ag = AuthGroupForName(&m->rrauth, slot, q->qnamehash, &q->qname);
- if (ag)
- {
- m->CurrentRecord = ag->members;
- while (m->CurrentRecord && m->CurrentRecord != ag->NewLocalOnlyRecords)
- {
- AuthRecord *rr = m->CurrentRecord;
- m->CurrentRecord = rr->next;
- //
- // If the question is mDNSInterface_LocalOnly, all records local to the machine should be used
- // to answer the query. This is handled in AnswerNewLocalOnlyQuestion.
- //
- // We handle mDNSInterface_Any and scoped questions here. See LocalOnlyRecordAnswersQuestion for more
- // details on how we handle this case. For P2P we just handle "Interface_Any" questions. For LocalOnly
- // we handle both mDNSInterface_Any and scoped questions.
-
- if (rr->ARType == AuthRecordLocalOnly || (rr->ARType == AuthRecordP2P && q->InterfaceID == mDNSInterface_Any))
- if (LocalOnlyRecordAnswersQuestion(rr, q))
- {
- AnswerLocalQuestionWithLocalAuthRecord(m, rr, mDNStrue);
- if (m->CurrentQuestion != q) break; // If callback deleted q, then we're finished here
- }
- }
- }
- m->CurrentRecord = mDNSNULL;
-
- if (m->CurrentQuestion != q) { LogInfo("AnswerNewQuestion: Question deleted while while giving LocalOnly record answers"); goto exit; }
-
- if (q->LOAddressAnswers)
- {
- LogInfo("AnswerNewQuestion: Question %p %##s (%s) answered using local auth records LOAddressAnswers %d",
- q, q->qname.c, DNSTypeName(q->qtype), q->LOAddressAnswers);
- goto exit;
- }
-
- // Before we go check the cache and ship this query on the wire, we have to be sure that there are
- // no local records that could possibly answer this question. As we did not check the NewLocalRecords, we
- // need to just peek at them to see whether it will answer this question. If it would answer, pretend
- // that we answered. AnswerAllLocalQuestionsWithLocalAuthRecord will answer shortly. This happens normally
- // when we add new /etc/hosts entries and restart the question. It is a new question and also a new record.
- if (ag)
- {
- lr = ag->NewLocalOnlyRecords;
- while (lr)
- {
- if (LORecordAnswersAddressType(lr) && LocalOnlyRecordAnswersQuestion(lr, q))
- {
- LogInfo("AnswerNewQuestion: Question %p %##s (%s) will be answered using new local auth records "
- " LOAddressAnswers %d", q, q->qname.c, DNSTypeName(q->qtype), q->LOAddressAnswers);
- goto exit;
- }
- lr = lr->next;
- }
- }
-
+{
+ mDNSBool ShouldQueryImmediately = mDNStrue;
+ DNSQuestion *const q = m->NewQuestions; // Grab the question we're going to answer
+ mDNSu32 slot = HashSlot(&q->qname);
+ CacheGroup *const cg = CacheGroupForName(m, slot, q->qnamehash, &q->qname);
+ mDNSBool AnsweredFromCache = mDNSfalse;
+
+ verbosedebugf("AnswerNewQuestion: Answering %##s (%s)", q->qname.c, DNSTypeName(q->qtype));
+
+ if (cg) CheckCacheExpiration(m, slot, cg);
+ if (m->NewQuestions != q) { LogInfo("AnswerNewQuestion: Question deleted while doing CheckCacheExpiration"); goto exit; }
+ m->NewQuestions = q->next;
+ // Advance NewQuestions to the next *after* calling CheckCacheExpiration, because if we advance it first
+ // then CheckCacheExpiration may give this question add/remove callbacks, and it's not yet ready for that.
+ //
+ // Also, CheckCacheExpiration() calls CacheRecordDeferredAdd() and CacheRecordRmv(), which invoke
+ // client callbacks, which may delete their own or any other question. Our mechanism for detecting
+ // whether our current m->NewQuestions question got deleted by one of these callbacks is to store the
+ // value of m->NewQuestions in 'q' before calling CheckCacheExpiration(), and then verify afterwards
+ // that they're still the same. If m->NewQuestions has changed (because mDNS_StopQuery_internal
+ // advanced it), that means the question was deleted, so we no longer need to worry about answering
+ // it (and indeed 'q' is now a dangling pointer, so dereferencing it at all would be bad, and the
+ // values we computed for slot and cg are now stale and relate to a question that no longer exists).
+ //
+ // We can't use the usual m->CurrentQuestion mechanism for this because CacheRecordDeferredAdd() and
+ // CacheRecordRmv() both use that themselves when walking the list of (non-new) questions generating callbacks.
+ // Fortunately mDNS_StopQuery_internal auto-advances both m->CurrentQuestion *AND* m->NewQuestions when
+ // deleting a question, so luckily we have an easy alternative way of detecting if our question got deleted.
+
+ if (m->lock_rrcache) LogMsg("AnswerNewQuestion ERROR! Cache already locked!");
+ // This should be safe, because calling the client's question callback may cause the
+ // question list to be modified, but should not ever cause the rrcache list to be modified.
+ // If the client's question callback deletes the question, then m->CurrentQuestion will
+ // be advanced, and we'll exit out of the loop
+ m->lock_rrcache = 1;
+ if (m->CurrentQuestion)
+ LogMsg("AnswerNewQuestion ERROR m->CurrentQuestion already set: %##s (%s)",
+ m->CurrentQuestion->qname.c, DNSTypeName(m->CurrentQuestion->qtype));
+ m->CurrentQuestion = q; // Indicate which question we're answering, so we'll know if it gets deleted
+
+ if (q->NoAnswer == NoAnswer_Fail)
+ {
+ LogMsg("AnswerNewQuestion: NoAnswer_Fail %##s (%s)", q->qname.c, DNSTypeName(q->qtype));
+ MakeNegativeCacheRecord(m, &m->rec.r, &q->qname, q->qnamehash, q->qtype, q->qclass, 60, mDNSInterface_Any, q->qDNSServer);
+ q->NoAnswer = NoAnswer_Normal; // Temporarily turn off answer suppression
+ AnswerCurrentQuestionWithResourceRecord(m, &m->rec.r, QC_addnocache);
+ // Don't touch the question if it has been stopped already
+ if (m->CurrentQuestion == q) q->NoAnswer = NoAnswer_Fail; // Restore NoAnswer state
+ m->rec.r.resrec.RecordType = 0; // Clear RecordType to show we're not still using it
+ }
+
+ if (m->CurrentQuestion != q)
+ {
+ LogInfo("AnswerNewQuestion: Question deleted while generating NoAnswer_Fail response");
+ goto exit;
+ }
+
+ // See if we want to tell it about LocalOnly/P2P records. If we answered them using LocalOnly
+ // or P2P record, then we are done.
+ if (AnswerQuestionWithLORecord(m, q, mDNSfalse))
+ goto exit;
+
+ // If we are not supposed to answer this question, generate a negative response.
+ // Temporarily suspend the SuppressQuery so that AnswerCurrentQuestionWithResourceRecord can answer the question
+ //
+ // If it is a question trying to validate some response, it already checked the cache for a response. If it still
+ // reissues a question it means it could not find the RRSIGs. So, we need to bypass the cache check and send
+ // the question out.
+ if (QuerySuppressed(q))
+ {
+ AnswerSuppressedQuestion(m, q);
+ }
+ else if (!q->ValidatingResponse)
+ {
+ CacheRecord *rr;
+ for (rr = cg ? cg->members : mDNSNULL; rr; rr=rr->next)
+ if (SameNameRecordAnswersQuestion(&rr->resrec, q))
+ {
+ // SecsSinceRcvd is whole number of elapsed seconds, rounded down
+ mDNSu32 SecsSinceRcvd = ((mDNSu32)(m->timenow - rr->TimeRcvd)) / mDNSPlatformOneSecond;
+ if (rr->resrec.rroriginalttl <= SecsSinceRcvd)
+ {
+ LogMsg("AnswerNewQuestion: How is rr->resrec.rroriginalttl %lu <= SecsSinceRcvd %lu for %s %d %d",
+ rr->resrec.rroriginalttl, SecsSinceRcvd, CRDisplayString(m, rr), m->timenow, rr->TimeRcvd);
+ continue; // Go to next one in loop
+ }
+
+ // If this record set is marked unique, then that means we can reasonably assume we have the whole set
+ // -- we don't need to rush out on the network and query immediately to see if there are more answers out there
+ if ((rr->resrec.RecordType & kDNSRecordTypePacketUniqueMask) || (q->ExpectUnique))
+ ShouldQueryImmediately = mDNSfalse;
+ q->CurrentAnswers++;
+ if (rr->resrec.rdlength > SmallRecordLimit) q->LargeAnswers++;
+ if (rr->resrec.RecordType & kDNSRecordTypePacketUniqueMask) q->UniqueAnswers++;
+ AnsweredFromCache = mDNStrue;
+ AnswerCurrentQuestionWithResourceRecord(m, rr, QC_add);
+ if (m->CurrentQuestion != q) break; // If callback deleted q, then we're finished here
+ }
+ else if (RRTypeIsAddressType(rr->resrec.rrtype) && RRTypeIsAddressType(q->qtype))
+ ShouldQueryImmediately = mDNSfalse;
+ }
+ // We don't use LogInfo for this "Question deleted" message because it happens so routinely that
+ // it's not remotely remarkable, and therefore unlikely to be of much help tracking down bugs.
+ if (m->CurrentQuestion != q) { debugf("AnswerNewQuestion: Question deleted while giving cache answers"); goto exit; }
+
+ // Neither a local record nor a cache entry could answer this question. If this question need to be retried
+ // with search domains, generate a negative response which will now retry after appending search domains.
+ // If the query was suppressed above, we already generated a negative response. When it gets unsuppressed,
+ // we will retry with search domains.
+ if (!QuerySuppressed(q) && !AnsweredFromCache && q->RetryWithSearchDomains)
+ {
+ LogInfo("AnswerNewQuestion: Generating response for retrying with search domains %##s (%s)", q->qname.c, DNSTypeName(q->qtype));
+ GenerateNegativeResponse(m, QC_forceresponse);
+ }
- // If we are not supposed to answer this question, generate a negative response.
- // Temporarily suspend the SuppressQuery so that AnswerCurrentQuestionWithResourceRecord can answer the question
- if (QuerySuppressed(q)) { q->SuppressQuery = mDNSfalse; GenerateNegativeResponse(m); q->SuppressQuery = mDNStrue; }
- else
- {
- CacheRecord *rr;
- for (rr = cg ? cg->members : mDNSNULL; rr; rr=rr->next)
- if (SameNameRecordAnswersQuestion(&rr->resrec, q))
- {
- // SecsSinceRcvd is whole number of elapsed seconds, rounded down
- mDNSu32 SecsSinceRcvd = ((mDNSu32)(m->timenow - rr->TimeRcvd)) / mDNSPlatformOneSecond;
- if (rr->resrec.rroriginalttl <= SecsSinceRcvd)
- {
- LogMsg("AnswerNewQuestion: How is rr->resrec.rroriginalttl %lu <= SecsSinceRcvd %lu for %s %d %d",
- rr->resrec.rroriginalttl, SecsSinceRcvd, CRDisplayString(m, rr), m->timenow, rr->TimeRcvd);
- continue; // Go to next one in loop
- }
-
- // If this record set is marked unique, then that means we can reasonably assume we have the whole set
- // -- we don't need to rush out on the network and query immediately to see if there are more answers out there
- if ((rr->resrec.RecordType & kDNSRecordTypePacketUniqueMask) || (q->ExpectUnique))
- ShouldQueryImmediately = mDNSfalse;
- q->CurrentAnswers++;
- if (rr->resrec.rdlength > SmallRecordLimit) q->LargeAnswers++;
- if (rr->resrec.RecordType & kDNSRecordTypePacketUniqueMask) q->UniqueAnswers++;
- AnsweredFromCache = mDNStrue;
- AnswerCurrentQuestionWithResourceRecord(m, rr, QC_add);
- if (m->CurrentQuestion != q) break; // If callback deleted q, then we're finished here
- }
- else if (RRTypeIsAddressType(rr->resrec.rrtype) && RRTypeIsAddressType(q->qtype))
- ShouldQueryImmediately = mDNSfalse;
- }
- // We don't use LogInfo for this "Question deleted" message because it happens so routinely that
- // it's not remotely remarkable, and therefore unlikely to be of much help tracking down bugs.
- if (m->CurrentQuestion != q) { debugf("AnswerNewQuestion: Question deleted while giving cache answers"); goto exit; }
-
- // Neither a local record nor a cache entry could answer this question. If this question need to be retried
- // with search domains, generate a negative response which will now retry after appending search domains.
- // If the query was suppressed above, we already generated a negative response. When it gets unsuppressed,
- // we will retry with search domains.
- if (!QuerySuppressed(q) && !AnsweredFromCache && q->RetryWithSearchDomains)
- {
- LogInfo("AnswerNewQuestion: Generating response for retrying with search domains %##s (%s)", q->qname.c, DNSTypeName(q->qtype));
- GenerateNegativeResponse(m);
- }
-
- if (m->CurrentQuestion != q) { debugf("AnswerNewQuestion: Question deleted while giving negative answer"); goto exit; }
-
- // Note: When a query gets suppressed or retried with search domains, we de-activate the question.
- // Hence we don't execute the following block of code for those cases.
- if (ShouldQueryImmediately && ActiveQuestion(q))
- {
- debugf("AnswerNewQuestion: ShouldQueryImmediately %##s (%s)", q->qname.c, DNSTypeName(q->qtype));
- q->ThisQInterval = InitialQuestionInterval;
- q->LastQTime = m->timenow - q->ThisQInterval;
- if (mDNSOpaque16IsZero(q->TargetQID)) // For mDNS, spread packets to avoid a burst of simultaneous queries
- {
- // Compute random delay in the range 1-6 seconds, then divide by 50 to get 20-120ms
- if (!m->RandomQueryDelay)
- m->RandomQueryDelay = (mDNSPlatformOneSecond + mDNSRandom(mDNSPlatformOneSecond*5) - 1) / 50 + 1;
- q->LastQTime += m->RandomQueryDelay;
- }
- }
-
- // IN ALL CASES make sure that m->NextScheduledQuery is set appropriately.
- // In cases where m->NewQuestions->DelayAnswering is set, we may have delayed generating our
- // answers for this question until *after* its scheduled transmission time, in which case
- // m->NextScheduledQuery may now be set to 'never', and in that case -- even though we're *not* doing
- // ShouldQueryImmediately -- we still need to make sure we set m->NextScheduledQuery correctly.
- SetNextQueryTime(m,q);
+ if (m->CurrentQuestion != q) { debugf("AnswerNewQuestion: Question deleted while giving negative answer"); goto exit; }
+
+ // Note: When a query gets suppressed or retried with search domains, we de-activate the question.
+ // Hence we don't execute the following block of code for those cases.
+ if (ShouldQueryImmediately && ActiveQuestion(q))
+ {
+ debugf("AnswerNewQuestion: ShouldQueryImmediately %##s (%s)", q->qname.c, DNSTypeName(q->qtype));
+ q->ThisQInterval = InitialQuestionInterval;
+ q->LastQTime = m->timenow - q->ThisQInterval;
+ if (mDNSOpaque16IsZero(q->TargetQID)) // For mDNS, spread packets to avoid a burst of simultaneous queries
+ {
+ // Compute random delay in the range 1-6 seconds, then divide by 50 to get 20-120ms
+ if (!m->RandomQueryDelay)
+ m->RandomQueryDelay = (mDNSPlatformOneSecond + mDNSRandom(mDNSPlatformOneSecond*5) - 1) / 50 + 1;
+ q->LastQTime += m->RandomQueryDelay;
+ }
+ }
+
+ // IN ALL CASES make sure that m->NextScheduledQuery is set appropriately.
+ // In cases where m->NewQuestions->DelayAnswering is set, we may have delayed generating our
+ // answers for this question until *after* its scheduled transmission time, in which case
+ // m->NextScheduledQuery may now be set to 'never', and in that case -- even though we're *not* doing
+ // ShouldQueryImmediately -- we still need to make sure we set m->NextScheduledQuery correctly.
+ SetNextQueryTime(m,q);
exit:
- m->CurrentQuestion = mDNSNULL;
- m->lock_rrcache = 0;
- }
+ m->CurrentQuestion = mDNSNULL;
+ m->lock_rrcache = 0;
+}
// When a NewLocalOnlyQuestion is created, AnswerNewLocalOnlyQuestion runs though our ResourceRecords delivering any
// appropriate answers, stopping if it reaches a NewLocalOnlyRecord -- these will be handled by AnswerAllLocalQuestionsWithLocalAuthRecord
mDNSlocal void AnswerNewLocalOnlyQuestion(mDNS *const m)
- {
- mDNSu32 slot;
- AuthGroup *ag;
- DNSQuestion *q = m->NewLocalOnlyQuestions; // Grab the question we're going to answer
- m->NewLocalOnlyQuestions = q->next; // Advance NewLocalOnlyQuestions to the next (if any)
-
- debugf("AnswerNewLocalOnlyQuestion: Answering %##s (%s)", q->qname.c, DNSTypeName(q->qtype));
-
- if (m->CurrentQuestion)
- LogMsg("AnswerNewLocalOnlyQuestion ERROR m->CurrentQuestion already set: %##s (%s)",
- m->CurrentQuestion->qname.c, DNSTypeName(m->CurrentQuestion->qtype));
- m->CurrentQuestion = q; // Indicate which question we're answering, so we'll know if it gets deleted
-
- if (m->CurrentRecord)
- LogMsg("AnswerNewLocalOnlyQuestion ERROR m->CurrentRecord already set %s", ARDisplayString(m, m->CurrentRecord));
-
- // 1. First walk the LocalOnly records answering the LocalOnly question
- // 2. As LocalOnly questions should also be answered by any other Auth records local to the machine,
- // walk the ResourceRecords list delivering the answers
- slot = AuthHashSlot(&q->qname);
- ag = AuthGroupForName(&m->rrauth, slot, q->qnamehash, &q->qname);
- if (ag)
- {
- m->CurrentRecord = ag->members;
- while (m->CurrentRecord && m->CurrentRecord != ag->NewLocalOnlyRecords)
- {
- AuthRecord *rr = m->CurrentRecord;
- m->CurrentRecord = rr->next;
- if (LocalOnlyRecordAnswersQuestion(rr, q))
- {
- AnswerLocalQuestionWithLocalAuthRecord(m, rr, mDNStrue);
- if (m->CurrentQuestion != q) break; // If callback deleted q, then we're finished here
- }
- }
- }
-
- if (m->CurrentQuestion == q)
- {
- m->CurrentRecord = m->ResourceRecords;
-
- while (m->CurrentRecord && m->CurrentRecord != m->NewLocalRecords)
- {
- AuthRecord *rr = m->CurrentRecord;
- m->CurrentRecord = rr->next;
- if (ResourceRecordAnswersQuestion(&rr->resrec, q))
- {
- AnswerLocalQuestionWithLocalAuthRecord(m, rr, mDNStrue);
- if (m->CurrentQuestion != q) break; // If callback deleted q, then we're finished here
- }
- }
- }
-
- m->CurrentQuestion = mDNSNULL;
- m->CurrentRecord = mDNSNULL;
- }
+{
+ mDNSu32 slot;
+ AuthGroup *ag;
+ DNSQuestion *q = m->NewLocalOnlyQuestions; // Grab the question we're going to answer
+ m->NewLocalOnlyQuestions = q->next; // Advance NewLocalOnlyQuestions to the next (if any)
+
+ debugf("AnswerNewLocalOnlyQuestion: Answering %##s (%s)", q->qname.c, DNSTypeName(q->qtype));
+
+ if (m->CurrentQuestion)
+ LogMsg("AnswerNewLocalOnlyQuestion ERROR m->CurrentQuestion already set: %##s (%s)",
+ m->CurrentQuestion->qname.c, DNSTypeName(m->CurrentQuestion->qtype));
+ m->CurrentQuestion = q; // Indicate which question we're answering, so we'll know if it gets deleted
+
+ if (m->CurrentRecord)
+ LogMsg("AnswerNewLocalOnlyQuestion ERROR m->CurrentRecord already set %s", ARDisplayString(m, m->CurrentRecord));
+
+ // 1. First walk the LocalOnly records answering the LocalOnly question
+ // 2. As LocalOnly questions should also be answered by any other Auth records local to the machine,
+ // walk the ResourceRecords list delivering the answers
+ slot = AuthHashSlot(&q->qname);
+ ag = AuthGroupForName(&m->rrauth, slot, q->qnamehash, &q->qname);
+ if (ag)
+ {
+ m->CurrentRecord = ag->members;
+ while (m->CurrentRecord && m->CurrentRecord != ag->NewLocalOnlyRecords)
+ {
+ AuthRecord *rr = m->CurrentRecord;
+ m->CurrentRecord = rr->next;
+ if (LocalOnlyRecordAnswersQuestion(rr, q))
+ {
+ AnswerLocalQuestionWithLocalAuthRecord(m, rr, mDNStrue);
+ if (m->CurrentQuestion != q) break; // If callback deleted q, then we're finished here
+ }
+ }
+ }
+
+ if (m->CurrentQuestion == q)
+ {
+ m->CurrentRecord = m->ResourceRecords;
+
+ while (m->CurrentRecord && m->CurrentRecord != m->NewLocalRecords)
+ {
+ AuthRecord *rr = m->CurrentRecord;
+ m->CurrentRecord = rr->next;
+ if (ResourceRecordAnswersQuestion(&rr->resrec, q))
+ {
+ AnswerLocalQuestionWithLocalAuthRecord(m, rr, mDNStrue);
+ if (m->CurrentQuestion != q) break; // If callback deleted q, then we're finished here
+ }
+ }
+ }
+
+ m->CurrentQuestion = mDNSNULL;
+ m->CurrentRecord = mDNSNULL;
+}
mDNSlocal CacheEntity *GetCacheEntity(mDNS *const m, const CacheGroup *const PreserveCG)
- {
- CacheEntity *e = mDNSNULL;
+{
+ CacheEntity *e = mDNSNULL;
- if (m->lock_rrcache) { LogMsg("GetFreeCacheRR ERROR! Cache already locked!"); return(mDNSNULL); }
- m->lock_rrcache = 1;
-
- // If we have no free records, ask the client layer to give us some more memory
- if (!m->rrcache_free && m->MainCallback)
- {
- if (m->rrcache_totalused != m->rrcache_size)
- LogMsg("GetFreeCacheRR: count mismatch: m->rrcache_totalused %lu != m->rrcache_size %lu",
- m->rrcache_totalused, m->rrcache_size);
-
- // We don't want to be vulnerable to a malicious attacker flooding us with an infinite
- // number of bogus records so that we keep growing our cache until the machine runs out of memory.
- // To guard against this, if our cache grows above 512kB (approx 3168 records at 164 bytes each),
- // and we're actively using less than 1/32 of that cache, then we purge all the unused records
- // and recycle them, instead of allocating more memory.
- if (m->rrcache_size > 5000 && m->rrcache_size / 32 > m->rrcache_active)
- LogInfo("Possible denial-of-service attack in progress: m->rrcache_size %lu; m->rrcache_active %lu",
- m->rrcache_size, m->rrcache_active);
- else
- {
- mDNS_DropLockBeforeCallback(); // Allow client to legally make mDNS API calls from the callback
- m->MainCallback(m, mStatus_GrowCache);
- mDNS_ReclaimLockAfterCallback(); // Decrement mDNS_reentrancy to block mDNS API calls again
- }
- }
-
- // If we still have no free records, recycle all the records we can.
- // Enumerating the entire cache is moderately expensive, so when we do it, we reclaim all the records we can in one pass.
- if (!m->rrcache_free)
- {
- mDNSu32 oldtotalused = m->rrcache_totalused;
- mDNSu32 slot;
- for (slot = 0; slot < CACHE_HASH_SLOTS; slot++)
- {
- CacheGroup **cp = &m->rrcache_hash[slot];
- while (*cp)
- {
- CacheRecord **rp = &(*cp)->members;
- while (*rp)
- {
- // Records that answer still-active questions are not candidates for recycling
- // Records that are currently linked into the CacheFlushRecords list may not be recycled, or we'll crash
- if ((*rp)->CRActiveQuestion || (*rp)->NextInCFList)
- rp=&(*rp)->next;
- else
- {
- CacheRecord *rr = *rp;
- *rp = (*rp)->next; // Cut record from list
- ReleaseCacheRecord(m, rr);
- }
- }
- if ((*cp)->rrcache_tail != rp)
- verbosedebugf("GetFreeCacheRR: Updating rrcache_tail[%lu] from %p to %p", slot, (*cp)->rrcache_tail, rp);
- (*cp)->rrcache_tail = rp;
- if ((*cp)->members || (*cp)==PreserveCG) cp=&(*cp)->next;
- else ReleaseCacheGroup(m, cp);
- }
- }
- LogInfo("GetCacheEntity recycled %d records to reduce cache from %d to %d",
- oldtotalused - m->rrcache_totalused, oldtotalused, m->rrcache_totalused);
- }
-
- if (m->rrcache_free) // If there are records in the free list, take one
- {
- e = m->rrcache_free;
- m->rrcache_free = e->next;
- if (++m->rrcache_totalused >= m->rrcache_report)
- {
- LogInfo("RR Cache now using %ld objects", m->rrcache_totalused);
- if (m->rrcache_report < 100) m->rrcache_report += 10;
- else if (m->rrcache_report < 1000) m->rrcache_report += 100;
- else m->rrcache_report += 1000;
- }
- mDNSPlatformMemZero(e, sizeof(*e));
- }
-
- m->lock_rrcache = 0;
-
- return(e);
- }
+ if (m->lock_rrcache) { LogMsg("GetFreeCacheRR ERROR! Cache already locked!"); return(mDNSNULL); }
+ m->lock_rrcache = 1;
+
+ // If we have no free records, ask the client layer to give us some more memory
+ if (!m->rrcache_free && m->MainCallback)
+ {
+ if (m->rrcache_totalused != m->rrcache_size)
+ LogMsg("GetFreeCacheRR: count mismatch: m->rrcache_totalused %lu != m->rrcache_size %lu",
+ m->rrcache_totalused, m->rrcache_size);
+
+ // We don't want to be vulnerable to a malicious attacker flooding us with an infinite
+ // number of bogus records so that we keep growing our cache until the machine runs out of memory.
+ // To guard against this, if our cache grows above 512kB (approx 3168 records at 164 bytes each),
+ // and we're actively using less than 1/32 of that cache, then we purge all the unused records
+ // and recycle them, instead of allocating more memory.
+ if (m->rrcache_size > 5000 && m->rrcache_size / 32 > m->rrcache_active)
+ LogInfo("Possible denial-of-service attack in progress: m->rrcache_size %lu; m->rrcache_active %lu",
+ m->rrcache_size, m->rrcache_active);
+ else
+ {
+ mDNS_DropLockBeforeCallback(); // Allow client to legally make mDNS API calls from the callback
+ m->MainCallback(m, mStatus_GrowCache);
+ mDNS_ReclaimLockAfterCallback(); // Decrement mDNS_reentrancy to block mDNS API calls again
+ }
+ }
+
+ // If we still have no free records, recycle all the records we can.
+ // Enumerating the entire cache is moderately expensive, so when we do it, we reclaim all the records we can in one pass.
+ if (!m->rrcache_free)
+ {
+ mDNSu32 oldtotalused = m->rrcache_totalused;
+ mDNSu32 slot;
+ for (slot = 0; slot < CACHE_HASH_SLOTS; slot++)
+ {
+ CacheGroup **cp = &m->rrcache_hash[slot];
+ while (*cp)
+ {
+ CacheRecord **rp = &(*cp)->members;
+ while (*rp)
+ {
+ // Records that answer still-active questions are not candidates for recycling
+ // Records that are currently linked into the CacheFlushRecords list may not be recycled, or we'll crash
+ if ((*rp)->CRActiveQuestion || (*rp)->NextInCFList)
+ rp=&(*rp)->next;
+ else
+ {
+ CacheRecord *rr = *rp;
+ *rp = (*rp)->next; // Cut record from list
+ ReleaseCacheRecord(m, rr);
+ }
+ }
+ if ((*cp)->rrcache_tail != rp)
+ verbosedebugf("GetFreeCacheRR: Updating rrcache_tail[%lu] from %p to %p", slot, (*cp)->rrcache_tail, rp);
+ (*cp)->rrcache_tail = rp;
+ if ((*cp)->members || (*cp)==PreserveCG) cp=&(*cp)->next;
+ else ReleaseCacheGroup(m, cp);
+ }
+ }
+ LogInfo("GetCacheEntity recycled %d records to reduce cache from %d to %d",
+ oldtotalused - m->rrcache_totalused, oldtotalused, m->rrcache_totalused);
+ }
+
+ if (m->rrcache_free) // If there are records in the free list, take one
+ {
+ e = m->rrcache_free;
+ m->rrcache_free = e->next;
+ if (++m->rrcache_totalused >= m->rrcache_report)
+ {
+ LogInfo("RR Cache now using %ld objects", m->rrcache_totalused);
+ if (m->rrcache_report < 100) m->rrcache_report += 10;
+ else if (m->rrcache_report < 1000) m->rrcache_report += 100;
+ else m->rrcache_report += 1000;
+ }
+ mDNSPlatformMemZero(e, sizeof(*e));
+ }
+
+ m->lock_rrcache = 0;
+
+ return(e);
+}
mDNSlocal CacheRecord *GetCacheRecord(mDNS *const m, CacheGroup *cg, mDNSu16 RDLength)
- {
- CacheRecord *r = (CacheRecord *)GetCacheEntity(m, cg);
- if (r)
- {
- r->resrec.rdata = (RData*)&r->smallrdatastorage; // By default, assume we're usually going to be using local storage
- if (RDLength > InlineCacheRDSize) // If RDLength is too big, allocate extra storage
- {
- r->resrec.rdata = (RData*)mDNSPlatformMemAllocate(sizeofRDataHeader + RDLength);
- if (r->resrec.rdata) r->resrec.rdata->MaxRDLength = r->resrec.rdlength = RDLength;
- else { ReleaseCacheEntity(m, (CacheEntity*)r); r = mDNSNULL; }
- }
- }
- return(r);
- }
+{
+ CacheRecord *r = (CacheRecord *)GetCacheEntity(m, cg);
+ if (r)
+ {
+ r->resrec.rdata = (RData*)&r->smallrdatastorage; // By default, assume we're usually going to be using local storage
+ if (RDLength > InlineCacheRDSize) // If RDLength is too big, allocate extra storage
+ {
+ r->resrec.rdata = (RData*)mDNSPlatformMemAllocate(sizeofRDataHeader + RDLength);
+ if (r->resrec.rdata) r->resrec.rdata->MaxRDLength = r->resrec.rdlength = RDLength;
+ else { ReleaseCacheEntity(m, (CacheEntity*)r); r = mDNSNULL; }
+ }
+ }
+ return(r);
+}
mDNSlocal CacheGroup *GetCacheGroup(mDNS *const m, const mDNSu32 slot, const ResourceRecord *const rr)
- {
- mDNSu16 namelen = DomainNameLength(rr->name);
- CacheGroup *cg = (CacheGroup*)GetCacheEntity(m, mDNSNULL);
- if (!cg) { LogMsg("GetCacheGroup: Failed to allocate memory for %##s", rr->name->c); return(mDNSNULL); }
- cg->next = m->rrcache_hash[slot];
- cg->namehash = rr->namehash;
- cg->members = mDNSNULL;
- cg->rrcache_tail = &cg->members;
- cg->name = (domainname*)cg->namestorage;
- //LogMsg("GetCacheGroup: %-10s %d-byte cache name %##s",
- // (namelen > InlineCacheGroupNameSize) ? "Allocating" : "Inline", namelen, rr->name->c);
- if (namelen > InlineCacheGroupNameSize) cg->name = mDNSPlatformMemAllocate(namelen);
- if (!cg->name)
- {
- LogMsg("GetCacheGroup: Failed to allocate name storage for %##s", rr->name->c);
- ReleaseCacheEntity(m, (CacheEntity*)cg);
- return(mDNSNULL);
- }
- AssignDomainName(cg->name, rr->name);
-
- if (CacheGroupForRecord(m, slot, rr)) LogMsg("GetCacheGroup: Already have CacheGroup for %##s", rr->name->c);
- m->rrcache_hash[slot] = cg;
- if (CacheGroupForRecord(m, slot, rr) != cg) LogMsg("GetCacheGroup: Not finding CacheGroup for %##s", rr->name->c);
-
- return(cg);
- }
+{
+ mDNSu16 namelen = DomainNameLength(rr->name);
+ CacheGroup *cg = (CacheGroup*)GetCacheEntity(m, mDNSNULL);
+ if (!cg) { LogMsg("GetCacheGroup: Failed to allocate memory for %##s", rr->name->c); return(mDNSNULL); }
+ cg->next = m->rrcache_hash[slot];
+ cg->namehash = rr->namehash;
+ cg->members = mDNSNULL;
+ cg->rrcache_tail = &cg->members;
+ if (namelen > sizeof(cg->namestorage))
+ cg->name = mDNSPlatformMemAllocate(namelen);
+ else
+ cg->name = (domainname*)cg->namestorage;
+ if (!cg->name)
+ {
+ LogMsg("GetCacheGroup: Failed to allocate name storage for %##s", rr->name->c);
+ ReleaseCacheEntity(m, (CacheEntity*)cg);
+ return(mDNSNULL);
+ }
+ AssignDomainName(cg->name, rr->name);
+
+ if (CacheGroupForRecord(m, slot, rr)) LogMsg("GetCacheGroup: Already have CacheGroup for %##s", rr->name->c);
+ m->rrcache_hash[slot] = cg;
+ if (CacheGroupForRecord(m, slot, rr) != cg) LogMsg("GetCacheGroup: Not finding CacheGroup for %##s", rr->name->c);
+
+ return(cg);
+}
mDNSexport void mDNS_PurgeCacheResourceRecord(mDNS *const m, CacheRecord *rr)
- {
- if (m->mDNS_busy != m->mDNS_reentrancy+1)
- LogMsg("mDNS_PurgeCacheResourceRecord: Lock not held! mDNS_busy (%ld) mDNS_reentrancy (%ld)", m->mDNS_busy, m->mDNS_reentrancy);
- // Make sure we mark this record as thoroughly expired -- we don't ever want to give
- // a positive answer using an expired record (e.g. from an interface that has gone away).
- // We don't want to clear CRActiveQuestion here, because that would leave the record subject to
- // summary deletion without giving the proper callback to any questions that are monitoring it.
- // By setting UnansweredQueries to MaxUnansweredQueries we ensure it won't trigger any further expiration queries.
- rr->TimeRcvd = m->timenow - mDNSPlatformOneSecond * 60;
- rr->UnansweredQueries = MaxUnansweredQueries;
- rr->resrec.rroriginalttl = 0;
- SetNextCacheCheckTimeForRecord(m, rr);
- }
+{
+ mDNS_CheckLock(m);
+
+ // Make sure we mark this record as thoroughly expired -- we don't ever want to give
+ // a positive answer using an expired record (e.g. from an interface that has gone away).
+ // We don't want to clear CRActiveQuestion here, because that would leave the record subject to
+ // summary deletion without giving the proper callback to any questions that are monitoring it.
+ // By setting UnansweredQueries to MaxUnansweredQueries we ensure it won't trigger any further expiration queries.
+ rr->TimeRcvd = m->timenow - mDNSPlatformOneSecond * 60;
+ rr->UnansweredQueries = MaxUnansweredQueries;
+ rr->resrec.rroriginalttl = 0;
+ SetNextCacheCheckTimeForRecord(m, rr);
+}
mDNSexport mDNSs32 mDNS_TimeNow(const mDNS *const m)
- {
- mDNSs32 time;
- mDNSPlatformLock(m);
- if (m->mDNS_busy)
- {
- LogMsg("mDNS_TimeNow called while holding mDNS lock. This is incorrect. Code protected by lock should just use m->timenow.");
- if (!m->timenow) LogMsg("mDNS_TimeNow: m->mDNS_busy is %ld but m->timenow not set", m->mDNS_busy);
- }
-
- if (m->timenow) time = m->timenow;
- else time = mDNS_TimeNow_NoLock(m);
- mDNSPlatformUnlock(m);
- return(time);
- }
+{
+ mDNSs32 time;
+ mDNSPlatformLock(m);
+ if (m->mDNS_busy)
+ {
+ LogMsg("mDNS_TimeNow called while holding mDNS lock. This is incorrect. Code protected by lock should just use m->timenow.");
+ if (!m->timenow) LogMsg("mDNS_TimeNow: m->mDNS_busy is %ld but m->timenow not set", m->mDNS_busy);
+ }
+
+ if (m->timenow) time = m->timenow;
+ else time = mDNS_TimeNow_NoLock(m);
+ mDNSPlatformUnlock(m);
+ return(time);
+}
// To avoid pointless CPU thrash, we use SetSPSProxyListChanged(X) to record the last interface that
// had its Sleep Proxy client list change, and defer to actual BPF reconfiguration to mDNS_Execute().
// (GetNextScheduledEvent() returns "now" when m->SPSProxyListChanged is set)
#define SetSPSProxyListChanged(X) do { \
- if (m->SPSProxyListChanged && m->SPSProxyListChanged != (X)) mDNSPlatformUpdateProxyList(m, m->SPSProxyListChanged); \
- m->SPSProxyListChanged = (X); } while(0)
+ if (m->SPSProxyListChanged && m->SPSProxyListChanged != (X)) mDNSPlatformUpdateProxyList(m, m->SPSProxyListChanged); \
+ m->SPSProxyListChanged = (X); } while(0)
// Called from mDNS_Execute() to expire stale proxy records
mDNSlocal void CheckProxyRecords(mDNS *const m, AuthRecord *list)
- {
- m->CurrentRecord = list;
- while (m->CurrentRecord)
- {
- AuthRecord *rr = m->CurrentRecord;
- if (rr->resrec.RecordType != kDNSRecordTypeDeregistering && rr->WakeUp.HMAC.l[0])
- {
- // If m->SPSSocket is NULL that means we're not acting as a sleep proxy any more,
- // so we need to cease proxying for *all* records we may have, expired or not.
- if (m->SPSSocket && m->timenow - rr->TimeExpire < 0) // If proxy record not expired yet, update m->NextScheduledSPS
- {
- if (m->NextScheduledSPS - rr->TimeExpire > 0)
- m->NextScheduledSPS = rr->TimeExpire;
- }
- else // else proxy record expired, so remove it
- {
- LogSPS("CheckProxyRecords: Removing %d H-MAC %.6a I-MAC %.6a %d %s",
- m->ProxyRecords, &rr->WakeUp.HMAC, &rr->WakeUp.IMAC, rr->WakeUp.seq, ARDisplayString(m, rr));
- SetSPSProxyListChanged(rr->resrec.InterfaceID);
- mDNS_Deregister_internal(m, rr, mDNS_Dereg_normal);
- // Don't touch rr after this -- memory may have been free'd
- }
- }
- // Mustn't advance m->CurrentRecord until *after* mDNS_Deregister_internal, because
- // new records could have been added to the end of the list as a result of that call.
- if (m->CurrentRecord == rr) // If m->CurrentRecord was not advanced for us, do it now
- m->CurrentRecord = rr->next;
- }
- }
+{
+ m->CurrentRecord = list;
+ while (m->CurrentRecord)
+ {
+ AuthRecord *rr = m->CurrentRecord;
+ if (rr->resrec.RecordType != kDNSRecordTypeDeregistering && rr->WakeUp.HMAC.l[0])
+ {
+ // If m->SPSSocket is NULL that means we're not acting as a sleep proxy any more,
+ // so we need to cease proxying for *all* records we may have, expired or not.
+ if (m->SPSSocket && m->timenow - rr->TimeExpire < 0) // If proxy record not expired yet, update m->NextScheduledSPS
+ {
+ if (m->NextScheduledSPS - rr->TimeExpire > 0)
+ m->NextScheduledSPS = rr->TimeExpire;
+ }
+ else // else proxy record expired, so remove it
+ {
+ LogSPS("CheckProxyRecords: Removing %d H-MAC %.6a I-MAC %.6a %d %s",
+ m->ProxyRecords, &rr->WakeUp.HMAC, &rr->WakeUp.IMAC, rr->WakeUp.seq, ARDisplayString(m, rr));
+ SetSPSProxyListChanged(rr->resrec.InterfaceID);
+ mDNS_Deregister_internal(m, rr, mDNS_Dereg_normal);
+ // Don't touch rr after this -- memory may have been free'd
+ }
+ }
+ // Mustn't advance m->CurrentRecord until *after* mDNS_Deregister_internal, because
+ // new records could have been added to the end of the list as a result of that call.
+ if (m->CurrentRecord == rr) // If m->CurrentRecord was not advanced for us, do it now
+ m->CurrentRecord = rr->next;
+ }
+}
mDNSlocal void CheckRmvEventsForLocalRecords(mDNS *const m)
- {
- while (m->CurrentRecord)
- {
- AuthRecord *rr = m->CurrentRecord;
- if (rr->AnsweredLocalQ && rr->resrec.RecordType == kDNSRecordTypeDeregistering)
- {
- debugf("CheckRmvEventsForLocalRecords: Generating local RMV events for %s", ARDisplayString(m, rr));
- rr->resrec.RecordType = kDNSRecordTypeShared;
- AnswerAllLocalQuestionsWithLocalAuthRecord(m, rr, mDNSfalse);
- if (m->CurrentRecord == rr) // If rr still exists in list, restore its state now
- {
- rr->resrec.RecordType = kDNSRecordTypeDeregistering;
- rr->AnsweredLocalQ = mDNSfalse;
- // SendResponses normally calls CompleteDeregistration after sending goodbyes.
- // For LocalOnly records, we don't do that and hence we need to do that here.
- if (RRLocalOnly(rr)) CompleteDeregistration(m, rr);
- }
- }
- if (m->CurrentRecord == rr) // If m->CurrentRecord was not auto-advanced, do it ourselves now
- m->CurrentRecord = rr->next;
- }
- }
+{
+ while (m->CurrentRecord)
+ {
+ AuthRecord *rr = m->CurrentRecord;
+ if (rr->AnsweredLocalQ && rr->resrec.RecordType == kDNSRecordTypeDeregistering)
+ {
+ debugf("CheckRmvEventsForLocalRecords: Generating local RMV events for %s", ARDisplayString(m, rr));
+ rr->resrec.RecordType = kDNSRecordTypeShared;
+ AnswerAllLocalQuestionsWithLocalAuthRecord(m, rr, mDNSfalse);
+ if (m->CurrentRecord == rr) // If rr still exists in list, restore its state now
+ {
+ rr->resrec.RecordType = kDNSRecordTypeDeregistering;
+ rr->AnsweredLocalQ = mDNSfalse;
+ // SendResponses normally calls CompleteDeregistration after sending goodbyes.
+ // For LocalOnly records, we don't do that and hence we need to do that here.
+ if (RRLocalOnly(rr)) CompleteDeregistration(m, rr);
+ }
+ }
+ if (m->CurrentRecord == rr) // If m->CurrentRecord was not auto-advanced, do it ourselves now
+ m->CurrentRecord = rr->next;
+ }
+}
mDNSlocal void TimeoutQuestions(mDNS *const m)
- {
- m->NextScheduledStopTime = m->timenow + 0x3FFFFFFF;
- if (m->CurrentQuestion)
- LogMsg("TimeoutQuestions ERROR m->CurrentQuestion already set: %##s (%s)", m->CurrentQuestion->qname.c,
- DNSTypeName(m->CurrentQuestion->qtype));
- m->CurrentQuestion = m->Questions;
- while (m->CurrentQuestion)
- {
- DNSQuestion *const q = m->CurrentQuestion;
- if (q->StopTime)
- {
- if (m->timenow - q->StopTime >= 0)
- {
- LogInfo("TimeoutQuestions: question %##s timed out, time %d", q->qname.c, m->timenow - q->StopTime);
- GenerateNegativeResponse(m);
- if (m->CurrentQuestion == q) q->StopTime = 0;
- }
- else
- {
- if (m->NextScheduledStopTime - q->StopTime > 0)
- m->NextScheduledStopTime = q->StopTime;
- }
- }
- // If m->CurrentQuestion wasn't modified out from under us, advance it now
- // We can't do this at the start of the loop because GenerateNegativeResponse
- // depends on having m->CurrentQuestion point to the right question
- if (m->CurrentQuestion == q)
- m->CurrentQuestion = q->next;
- }
- m->CurrentQuestion = mDNSNULL;
- }
+{
+ m->NextScheduledStopTime = m->timenow + 0x3FFFFFFF;
+ if (m->CurrentQuestion)
+ LogMsg("TimeoutQuestions ERROR m->CurrentQuestion already set: %##s (%s)", m->CurrentQuestion->qname.c,
+ DNSTypeName(m->CurrentQuestion->qtype));
+ m->CurrentQuestion = m->Questions;
+ while (m->CurrentQuestion)
+ {
+ DNSQuestion *const q = m->CurrentQuestion;
+ if (q->StopTime)
+ {
+ if (!q->TimeoutQuestion)
+ LogMsg("TimeoutQuestions: ERROR!! TimeoutQuestion not set, but StopTime set for %##s (%s)", q->qname.c, DNSTypeName(q->qtype));
+
+ if (m->timenow - q->StopTime >= 0)
+ {
+ LogInfo("TimeoutQuestions: question %p %##s timed out, time %d", q, q->qname.c, m->timenow - q->StopTime);
+ GenerateNegativeResponse(m, QC_forceresponse);
+ if (m->CurrentQuestion == q) q->StopTime = 0;
+ }
+ else
+ {
+ if (m->NextScheduledStopTime - q->StopTime > 0)
+ m->NextScheduledStopTime = q->StopTime;
+ }
+ }
+ // If m->CurrentQuestion wasn't modified out from under us, advance it now
+ // We can't do this at the start of the loop because GenerateNegativeResponse
+ // depends on having m->CurrentQuestion point to the right question
+ if (m->CurrentQuestion == q)
+ m->CurrentQuestion = q->next;
+ }
+ m->CurrentQuestion = mDNSNULL;
+}
+
+mDNSlocal void mDNSCoreFreeProxyRR(mDNS *const m)
+{
+ AuthRecord *rrPtr = m->SPSRRSet, *rrNext = mDNSNULL;
+ LogSPS("%s : Freeing stored sleep proxy A/AAAA records", __func__);
+ while (rrPtr)
+ {
+ rrNext = rrPtr->next;
+ mDNSPlatformMemFree(rrPtr);
+ rrPtr = rrNext;
+ }
+ m->SPSRRSet = mDNSNULL;
+}
mDNSexport mDNSs32 mDNS_Execute(mDNS *const m)
- {
- mDNS_Lock(m); // Must grab lock before trying to read m->timenow
+{
+ mDNS_Lock(m); // Must grab lock before trying to read m->timenow
- if (m->timenow - m->NextScheduledEvent >= 0)
- {
- int i;
- AuthRecord *head, *tail;
- mDNSu32 slot;
- AuthGroup *ag;
+#if APPLE_OSX_mDNSResponder
+ mDNSLogStatistics(m);
+#endif // APPLE_OSX_mDNSResponder
- verbosedebugf("mDNS_Execute");
+ if (m->timenow - m->NextScheduledEvent >= 0)
+ {
+ int i;
+ AuthRecord *head, *tail;
+ mDNSu32 slot;
+ AuthGroup *ag;
+
+ verbosedebugf("mDNS_Execute");
+
+ if (m->CurrentQuestion)
+ LogMsg("mDNS_Execute: ERROR m->CurrentQuestion already set: %##s (%s)",
+ m->CurrentQuestion->qname.c, DNSTypeName(m->CurrentQuestion->qtype));
+
+ if (m->CurrentRecord)
+ LogMsg("mDNS_Execute: ERROR m->CurrentRecord already set: %s", ARDisplayString(m, m->CurrentRecord));
+
+ // 1. If we're past the probe suppression time, we can clear it
+ if (m->SuppressProbes && m->timenow - m->SuppressProbes >= 0) m->SuppressProbes = 0;
+
+ // 2. If it's been more than ten seconds since the last probe failure, we can clear the counter
+ if (m->NumFailedProbes && m->timenow - m->ProbeFailTime >= mDNSPlatformOneSecond * 10) m->NumFailedProbes = 0;
+
+ // 3. Purge our cache of stale old records
+ if (m->rrcache_size && m->timenow - m->NextCacheCheck >= 0)
+ {
+ mDNSu32 numchecked = 0;
+ m->NextCacheCheck = m->timenow + 0x3FFFFFFF;
+ for (slot = 0; slot < CACHE_HASH_SLOTS; slot++)
+ {
+ if (m->timenow - m->rrcache_nextcheck[slot] >= 0)
+ {
+ CacheGroup **cp = &m->rrcache_hash[slot];
+ m->rrcache_nextcheck[slot] = m->timenow + 0x3FFFFFFF;
+ while (*cp)
+ {
+ debugf("m->NextCacheCheck %4d Slot %3d %##s", numchecked, slot, *cp ? (*cp)->name : (domainname*)"\x04NULL");
+ numchecked++;
+ CheckCacheExpiration(m, slot, *cp);
+ if ((*cp)->members) cp=&(*cp)->next;
+ else ReleaseCacheGroup(m, cp);
+ }
+ }
+ // Even if we didn't need to actually check this slot yet, still need to
+ // factor its nextcheck time into our overall NextCacheCheck value
+ if (m->NextCacheCheck - m->rrcache_nextcheck[slot] > 0)
+ m->NextCacheCheck = m->rrcache_nextcheck[slot];
+ }
+ debugf("m->NextCacheCheck %4d checked, next in %d", numchecked, m->NextCacheCheck - m->timenow);
+ }
+
+ if (m->timenow - m->NextScheduledSPS >= 0)
+ {
+ m->NextScheduledSPS = m->timenow + 0x3FFFFFFF;
+ CheckProxyRecords(m, m->DuplicateRecords); // Clear m->DuplicateRecords first, then m->ResourceRecords
+ CheckProxyRecords(m, m->ResourceRecords);
+ }
+
+ SetSPSProxyListChanged(mDNSNULL); // Perform any deferred BPF reconfiguration now
+
+ // Check to see if we need to send any keepalives. Do this after we called CheckProxyRecords above
+ // as records could have expired during that check
+ if (m->timenow - m->NextScheduledKA >= 0)
+ {
+ m->NextScheduledKA = m->timenow + 0x3FFFFFFF;
+ mDNS_SendKeepalives(m);
+ }
+
+ // Clear AnnounceOwner if necessary. (Do this *before* SendQueries() and SendResponses().)
+ if (m->AnnounceOwner && m->timenow - m->AnnounceOwner >= 0)
+ {
+ m->AnnounceOwner = 0;
+ }
+
+ if (m->DelaySleep && m->timenow - m->DelaySleep >= 0)
+ {
+ m->DelaySleep = 0;
+ if (m->SleepState == SleepState_Transferring)
+ {
+ LogSPS("Re-sleep delay passed; now checking for Sleep Proxy Servers");
+ BeginSleepProcessing(m);
+ }
+ }
+
+ // 4. See if we can answer any of our new local questions from the cache
+ for (i=0; m->NewQuestions && i<1000; i++)
+ {
+ if (m->NewQuestions->DelayAnswering && m->timenow - m->NewQuestions->DelayAnswering < 0) break;
+ AnswerNewQuestion(m);
+ }
+ if (i >= 1000) LogMsg("mDNS_Execute: AnswerNewQuestion exceeded loop limit");
+
+ // Make sure we deliver *all* local RMV events, and clear the corresponding rr->AnsweredLocalQ flags, *before*
+ // we begin generating *any* new ADD events in the m->NewLocalOnlyQuestions and m->NewLocalRecords loops below.
+ for (i=0; i<1000 && m->LocalRemoveEvents; i++)
+ {
+ m->LocalRemoveEvents = mDNSfalse;
+ m->CurrentRecord = m->ResourceRecords;
+ CheckRmvEventsForLocalRecords(m);
+ // Walk the LocalOnly records and deliver the RMV events
+ for (slot = 0; slot < AUTH_HASH_SLOTS; slot++)
+ for (ag = m->rrauth.rrauth_hash[slot]; ag; ag = ag->next)
+ {
+ m->CurrentRecord = ag->members;
+ if (m->CurrentRecord) CheckRmvEventsForLocalRecords(m);
+ }
+ }
+
+ if (i >= 1000) LogMsg("mDNS_Execute: m->LocalRemoveEvents exceeded loop limit");
+
+ for (i=0; m->NewLocalOnlyQuestions && i<1000; i++) AnswerNewLocalOnlyQuestion(m);
+ if (i >= 1000) LogMsg("mDNS_Execute: AnswerNewLocalOnlyQuestion exceeded loop limit");
+
+ head = tail = mDNSNULL;
+ for (i=0; i<1000 && m->NewLocalRecords && m->NewLocalRecords != head; i++)
+ {
+ AuthRecord *rr = m->NewLocalRecords;
+ m->NewLocalRecords = m->NewLocalRecords->next;
+ if (LocalRecordReady(rr))
+ {
+ debugf("mDNS_Execute: Delivering Add event with LocalAuthRecord %s", ARDisplayString(m, rr));
+ AnswerAllLocalQuestionsWithLocalAuthRecord(m, rr, mDNStrue);
+ }
+ else if (!rr->next)
+ {
+ // If we have just one record that is not ready, we don't have to unlink and
+ // reinsert. As the NewLocalRecords will be NULL for this case, the loop will
+ // terminate and set the NewLocalRecords to rr.
+ debugf("mDNS_Execute: Just one LocalAuthRecord %s, breaking out of the loop early", ARDisplayString(m, rr));
+ if (head != mDNSNULL || m->NewLocalRecords != mDNSNULL)
+ LogMsg("mDNS_Execute: ERROR!!: head %p, NewLocalRecords %p", head, m->NewLocalRecords);
+
+ head = rr;
+ }
+ else
+ {
+ AuthRecord **p = &m->ResourceRecords; // Find this record in our list of active records
+ debugf("mDNS_Execute: Skipping LocalAuthRecord %s", ARDisplayString(m, rr));
+ // if this is the first record we are skipping, move to the end of the list.
+ // if we have already skipped records before, append it at the end.
+ while (*p && *p != rr) p=&(*p)->next;
+ if (*p) *p = rr->next; // Cut this record from the list
+ else { LogMsg("mDNS_Execute: ERROR!! Cannot find record %s in ResourceRecords list", ARDisplayString(m, rr)); break; }
+ if (!head)
+ {
+ while (*p) p=&(*p)->next;
+ *p = rr;
+ head = tail = rr;
+ }
+ else
+ {
+ tail->next = rr;
+ tail = rr;
+ }
+ rr->next = mDNSNULL;
+ }
+ }
+ m->NewLocalRecords = head;
+ debugf("mDNS_Execute: Setting NewLocalRecords to %s", (head ? ARDisplayString(m, head) : "NULL"));
+
+ if (i >= 1000) LogMsg("mDNS_Execute: m->NewLocalRecords exceeded loop limit");
+
+ // Check to see if we have any new LocalOnly/P2P records to examine for delivering
+ // to our local questions
+ if (m->NewLocalOnlyRecords)
+ {
+ m->NewLocalOnlyRecords = mDNSfalse;
+ for (slot = 0; slot < AUTH_HASH_SLOTS; slot++)
+ for (ag = m->rrauth.rrauth_hash[slot]; ag; ag = ag->next)
+ {
+ for (i=0; i<100 && ag->NewLocalOnlyRecords; i++)
+ {
+ AuthRecord *rr = ag->NewLocalOnlyRecords;
+ ag->NewLocalOnlyRecords = ag->NewLocalOnlyRecords->next;
+ // LocalOnly records should always be ready as they never probe
+ if (LocalRecordReady(rr))
+ {
+ debugf("mDNS_Execute: Delivering Add event with LocalAuthRecord %s", ARDisplayString(m, rr));
+ AnswerAllLocalQuestionsWithLocalAuthRecord(m, rr, mDNStrue);
+ }
+ else LogMsg("mDNS_Execute: LocalOnlyRecord %s not ready", ARDisplayString(m, rr));
+ }
+ // We limit about 100 per AuthGroup that can be serviced at a time
+ if (i >= 100) LogMsg("mDNS_Execute: ag->NewLocalOnlyRecords exceeded loop limit");
+ }
+ }
+
+ // 5. See what packets we need to send
+ if (m->mDNSPlatformStatus != mStatus_NoError || (m->SleepState == SleepState_Sleeping))
+ DiscardDeregistrations(m);
+ if (m->mDNSPlatformStatus == mStatus_NoError && (m->SuppressSending == 0 || m->timenow - m->SuppressSending >= 0))
+ {
+ // If the platform code is ready, and we're not suppressing packet generation right now
+ // then send our responses, probes, and questions.
+ // We check the cache first, because there might be records close to expiring that trigger questions to refresh them.
+ // We send queries next, because there might be final-stage probes that complete their probing here, causing
+ // them to advance to announcing state, and we want those to be included in any announcements we send out.
+ // Finally, we send responses, including the previously mentioned records that just completed probing.
+ m->SuppressSending = 0;
+
+ // 6. Send Query packets. This may cause some probing records to advance to announcing state
+ if (m->timenow - m->NextScheduledQuery >= 0 || m->timenow - m->NextScheduledProbe >= 0) SendQueries(m);
+ if (m->timenow - m->NextScheduledQuery >= 0)
+ {
+ DNSQuestion *q;
+ LogMsg("mDNS_Execute: SendQueries didn't send all its queries (%d - %d = %d) will try again in one second",
+ m->timenow, m->NextScheduledQuery, m->timenow - m->NextScheduledQuery);
+ m->NextScheduledQuery = m->timenow + mDNSPlatformOneSecond;
+ for (q = m->Questions; q && q != m->NewQuestions; q=q->next)
+ if (ActiveQuestion(q) && m->timenow - NextQSendTime(q) >= 0)
+ LogMsg("mDNS_Execute: SendQueries didn't send %##s (%s)", q->qname.c, DNSTypeName(q->qtype));
+ }
+ if (m->timenow - m->NextScheduledProbe >= 0)
+ {
+ LogMsg("mDNS_Execute: SendQueries didn't send all its probes (%d - %d = %d) will try again in one second",
+ m->timenow, m->NextScheduledProbe, m->timenow - m->NextScheduledProbe);
+ m->NextScheduledProbe = m->timenow + mDNSPlatformOneSecond;
+ }
+
+ // 7. Send Response packets, including probing records just advanced to announcing state
+ if (m->timenow - m->NextScheduledResponse >= 0) SendResponses(m);
+ if (m->timenow - m->NextScheduledResponse >= 0)
+ {
+ LogMsg("mDNS_Execute: SendResponses didn't send all its responses; will try again in one second");
+ m->NextScheduledResponse = m->timenow + mDNSPlatformOneSecond;
+ }
+ }
+
+ // Clear RandomDelay values, ready to pick a new different value next time
+ m->RandomQueryDelay = 0;
+ m->RandomReconfirmDelay = 0;
+
+ if (m->NextScheduledStopTime && m->timenow - m->NextScheduledStopTime >= 0) TimeoutQuestions(m);
+#ifndef UNICAST_DISABLED
+ if (m->NextSRVUpdate && m->timenow - m->NextSRVUpdate >= 0) UpdateAllSRVRecords(m);
+ if (m->timenow - m->NextScheduledNATOp >= 0) CheckNATMappings(m);
+ if (m->timenow - m->NextuDNSEvent >= 0) uDNS_Tasks(m);
+#endif
+ }
+
+ // Note about multi-threaded systems:
+ // On a multi-threaded system, some other thread could run right after the mDNS_Unlock(),
+ // performing mDNS API operations that change our next scheduled event time.
+ //
+ // On multi-threaded systems (like the current Windows implementation) that have a single main thread
+ // calling mDNS_Execute() (and other threads allowed to call mDNS API routines) it is the responsibility
+ // of the mDNSPlatformUnlock() routine to signal some kind of stateful condition variable that will
+ // signal whatever blocking primitive the main thread is using, so that it will wake up and execute one
+ // more iteration of its loop, and immediately call mDNS_Execute() again. The signal has to be stateful
+ // in the sense that if the main thread has not yet entered its blocking primitive, then as soon as it
+ // does, the state of the signal will be noticed, causing the blocking primitive to return immediately
+ // without blocking. This avoids the race condition between the signal from the other thread arriving
+ // just *before* or just *after* the main thread enters the blocking primitive.
+ //
+ // On multi-threaded systems (like the current Mac OS 9 implementation) that are entirely timer-driven,
+ // with no main mDNS_Execute() thread, it is the responsibility of the mDNSPlatformUnlock() routine to
+ // set the timer according to the m->NextScheduledEvent value, and then when the timer fires, the timer
+ // callback function should call mDNS_Execute() (and ignore the return value, which may already be stale
+ // by the time it gets to the timer callback function).
+
+ mDNS_Unlock(m); // Calling mDNS_Unlock is what gives m->NextScheduledEvent its new value
+ return(m->NextScheduledEvent);
+}
- if (m->CurrentQuestion)
- LogMsg("mDNS_Execute: ERROR m->CurrentQuestion already set: %##s (%s)",
- m->CurrentQuestion->qname.c, DNSTypeName(m->CurrentQuestion->qtype));
-
- if (m->CurrentRecord)
- LogMsg("mDNS_Execute: ERROR m->CurrentRecord already set: %s", ARDisplayString(m, m->CurrentRecord));
-
- // 1. If we're past the probe suppression time, we can clear it
- if (m->SuppressProbes && m->timenow - m->SuppressProbes >= 0) m->SuppressProbes = 0;
-
- // 2. If it's been more than ten seconds since the last probe failure, we can clear the counter
- if (m->NumFailedProbes && m->timenow - m->ProbeFailTime >= mDNSPlatformOneSecond * 10) m->NumFailedProbes = 0;
-
- // 3. Purge our cache of stale old records
- if (m->rrcache_size && m->timenow - m->NextCacheCheck >= 0)
- {
- mDNSu32 numchecked = 0;
- m->NextCacheCheck = m->timenow + 0x3FFFFFFF;
- for (slot = 0; slot < CACHE_HASH_SLOTS; slot++)
- {
- if (m->timenow - m->rrcache_nextcheck[slot] >= 0)
- {
- CacheGroup **cp = &m->rrcache_hash[slot];
- m->rrcache_nextcheck[slot] = m->timenow + 0x3FFFFFFF;
- while (*cp)
- {
- debugf("m->NextCacheCheck %4d Slot %3d %##s", numchecked, slot, *cp ? (*cp)->name : (domainname*)"\x04NULL");
- numchecked++;
- CheckCacheExpiration(m, slot, *cp);
- if ((*cp)->members) cp=&(*cp)->next;
- else ReleaseCacheGroup(m, cp);
- }
- }
- // Even if we didn't need to actually check this slot yet, still need to
- // factor its nextcheck time into our overall NextCacheCheck value
- if (m->NextCacheCheck - m->rrcache_nextcheck[slot] > 0)
- m->NextCacheCheck = m->rrcache_nextcheck[slot];
- }
- debugf("m->NextCacheCheck %4d checked, next in %d", numchecked, m->NextCacheCheck - m->timenow);
- }
-
- if (m->timenow - m->NextScheduledSPS >= 0)
- {
- m->NextScheduledSPS = m->timenow + 0x3FFFFFFF;
- CheckProxyRecords(m, m->DuplicateRecords); // Clear m->DuplicateRecords first, then m->ResourceRecords
- CheckProxyRecords(m, m->ResourceRecords);
- }
-
- SetSPSProxyListChanged(mDNSNULL); // Perform any deferred BPF reconfiguration now
-
- // Clear AnnounceOwner if necessary. (Do this *before* SendQueries() and SendResponses().)
- if (m->AnnounceOwner && m->timenow - m->AnnounceOwner >= 0) m->AnnounceOwner = 0;
-
- if (m->DelaySleep && m->timenow - m->DelaySleep >= 0)
- {
- m->DelaySleep = 0;
- if (m->SleepState == SleepState_Transferring)
- {
- LogSPS("Re-sleep delay passed; now checking for Sleep Proxy Servers");
- BeginSleepProcessing(m);
- }
- }
-
- // 4. See if we can answer any of our new local questions from the cache
- for (i=0; m->NewQuestions && i<1000; i++)
- {
- if (m->NewQuestions->DelayAnswering && m->timenow - m->NewQuestions->DelayAnswering < 0) break;
- AnswerNewQuestion(m);
- }
- if (i >= 1000) LogMsg("mDNS_Execute: AnswerNewQuestion exceeded loop limit");
-
- // Make sure we deliver *all* local RMV events, and clear the corresponding rr->AnsweredLocalQ flags, *before*
- // we begin generating *any* new ADD events in the m->NewLocalOnlyQuestions and m->NewLocalRecords loops below.
- for (i=0; i<1000 && m->LocalRemoveEvents; i++)
- {
- m->LocalRemoveEvents = mDNSfalse;
- m->CurrentRecord = m->ResourceRecords;
- CheckRmvEventsForLocalRecords(m);
- // Walk the LocalOnly records and deliver the RMV events
- for (slot = 0; slot < AUTH_HASH_SLOTS; slot++)
- for (ag = m->rrauth.rrauth_hash[slot]; ag; ag = ag->next)
- {
- m->CurrentRecord = ag->members;
- if (m->CurrentRecord) CheckRmvEventsForLocalRecords(m);
- }
- }
-
- if (i >= 1000) LogMsg("mDNS_Execute: m->LocalRemoveEvents exceeded loop limit");
-
- for (i=0; m->NewLocalOnlyQuestions && i<1000; i++) AnswerNewLocalOnlyQuestion(m);
- if (i >= 1000) LogMsg("mDNS_Execute: AnswerNewLocalOnlyQuestion exceeded loop limit");
-
- head = tail = mDNSNULL;
- for (i=0; i<1000 && m->NewLocalRecords && m->NewLocalRecords != head; i++)
- {
- AuthRecord *rr = m->NewLocalRecords;
- m->NewLocalRecords = m->NewLocalRecords->next;
- if (LocalRecordReady(rr))
- {
- debugf("mDNS_Execute: Delivering Add event with LocalAuthRecord %s", ARDisplayString(m, rr));
- AnswerAllLocalQuestionsWithLocalAuthRecord(m, rr, mDNStrue);
- }
- else if (!rr->next)
- {
- // If we have just one record that is not ready, we don't have to unlink and
- // reinsert. As the NewLocalRecords will be NULL for this case, the loop will
- // terminate and set the NewLocalRecords to rr.
- debugf("mDNS_Execute: Just one LocalAuthRecord %s, breaking out of the loop early", ARDisplayString(m, rr));
- if (head != mDNSNULL || m->NewLocalRecords != mDNSNULL)
- LogMsg("mDNS_Execute: ERROR!!: head %p, NewLocalRecords %p", head, m->NewLocalRecords);
-
- head = rr;
- }
- else
- {
- AuthRecord **p = &m->ResourceRecords; // Find this record in our list of active records
- debugf("mDNS_Execute: Skipping LocalAuthRecord %s", ARDisplayString(m, rr));
- // if this is the first record we are skipping, move to the end of the list.
- // if we have already skipped records before, append it at the end.
- while (*p && *p != rr) p=&(*p)->next;
- if (*p) *p = rr->next; // Cut this record from the list
- else { LogMsg("mDNS_Execute: ERROR!! Cannot find record %s in ResourceRecords list", ARDisplayString(m, rr)); break; }
- if (!head)
- {
- while (*p) p=&(*p)->next;
- *p = rr;
- head = tail = rr;
- }
- else
- {
- tail->next = rr;
- tail = rr;
- }
- rr->next = mDNSNULL;
- }
- }
- m->NewLocalRecords = head;
- debugf("mDNS_Execute: Setting NewLocalRecords to %s", (head ? ARDisplayString(m, head) : "NULL"));
-
- if (i >= 1000) LogMsg("mDNS_Execute: m->NewLocalRecords exceeded loop limit");
-
- // Check to see if we have any new LocalOnly/P2P records to examine for delivering
- // to our local questions
- if (m->NewLocalOnlyRecords)
- {
- m->NewLocalOnlyRecords = mDNSfalse;
- for (slot = 0; slot < AUTH_HASH_SLOTS; slot++)
- for (ag = m->rrauth.rrauth_hash[slot]; ag; ag = ag->next)
- {
- for (i=0; i<100 && ag->NewLocalOnlyRecords; i++)
- {
- AuthRecord *rr = ag->NewLocalOnlyRecords;
- ag->NewLocalOnlyRecords = ag->NewLocalOnlyRecords->next;
- // LocalOnly records should always be ready as they never probe
- if (LocalRecordReady(rr))
- {
- debugf("mDNS_Execute: Delivering Add event with LocalAuthRecord %s", ARDisplayString(m, rr));
- AnswerAllLocalQuestionsWithLocalAuthRecord(m, rr, mDNStrue);
- }
- else LogMsg("mDNS_Execute: LocalOnlyRecord %s not ready", ARDisplayString(m, rr));
- }
- // We limit about 100 per AuthGroup that can be serviced at a time
- if (i >= 100) LogMsg("mDNS_Execute: ag->NewLocalOnlyRecords exceeded loop limit");
- }
- }
-
- // 5. Some questions may have picked a new DNS server and the cache may answer these questions now.
- AnswerQuestionsForDNSServerChanges(m);
-
- // 6. See what packets we need to send
- if (m->mDNSPlatformStatus != mStatus_NoError || (m->SleepState == SleepState_Sleeping))
- DiscardDeregistrations(m);
- if (m->mDNSPlatformStatus == mStatus_NoError && (m->SuppressSending == 0 || m->timenow - m->SuppressSending >= 0))
- {
- // If the platform code is ready, and we're not suppressing packet generation right now
- // then send our responses, probes, and questions.
- // We check the cache first, because there might be records close to expiring that trigger questions to refresh them.
- // We send queries next, because there might be final-stage probes that complete their probing here, causing
- // them to advance to announcing state, and we want those to be included in any announcements we send out.
- // Finally, we send responses, including the previously mentioned records that just completed probing.
- m->SuppressSending = 0;
-
- // 7. Send Query packets. This may cause some probing records to advance to announcing state
- if (m->timenow - m->NextScheduledQuery >= 0 || m->timenow - m->NextScheduledProbe >= 0) SendQueries(m);
- if (m->timenow - m->NextScheduledQuery >= 0)
- {
- DNSQuestion *q;
- LogMsg("mDNS_Execute: SendQueries didn't send all its queries (%d - %d = %d) will try again in one second",
- m->timenow, m->NextScheduledQuery, m->timenow - m->NextScheduledQuery);
- m->NextScheduledQuery = m->timenow + mDNSPlatformOneSecond;
- for (q = m->Questions; q && q != m->NewQuestions; q=q->next)
- if (ActiveQuestion(q) && m->timenow - NextQSendTime(q) >= 0)
- LogMsg("mDNS_Execute: SendQueries didn't send %##s (%s)", q->qname.c, DNSTypeName(q->qtype));
- }
- if (m->timenow - m->NextScheduledProbe >= 0)
- {
- LogMsg("mDNS_Execute: SendQueries didn't send all its probes (%d - %d = %d) will try again in one second",
- m->timenow, m->NextScheduledProbe, m->timenow - m->NextScheduledProbe);
- m->NextScheduledProbe = m->timenow + mDNSPlatformOneSecond;
- }
-
- // 8. Send Response packets, including probing records just advanced to announcing state
- if (m->timenow - m->NextScheduledResponse >= 0) SendResponses(m);
- if (m->timenow - m->NextScheduledResponse >= 0)
- {
- LogMsg("mDNS_Execute: SendResponses didn't send all its responses; will try again in one second");
- m->NextScheduledResponse = m->timenow + mDNSPlatformOneSecond;
- }
- }
-
- // Clear RandomDelay values, ready to pick a new different value next time
- m->RandomQueryDelay = 0;
- m->RandomReconfirmDelay = 0;
-
- if (m->NextScheduledStopTime && m->timenow - m->NextScheduledStopTime >= 0) TimeoutQuestions(m);
#ifndef UNICAST_DISABLED
- if (m->NextSRVUpdate && m->timenow - m->NextSRVUpdate >= 0) UpdateAllSRVRecords(m);
- if (m->timenow - m->NextScheduledNATOp >= 0) CheckNATMappings(m);
- if (m->timenow - m->NextuDNSEvent >= 0) uDNS_Tasks(m);
-#endif
- }
-
- // Note about multi-threaded systems:
- // On a multi-threaded system, some other thread could run right after the mDNS_Unlock(),
- // performing mDNS API operations that change our next scheduled event time.
- //
- // On multi-threaded systems (like the current Windows implementation) that have a single main thread
- // calling mDNS_Execute() (and other threads allowed to call mDNS API routines) it is the responsibility
- // of the mDNSPlatformUnlock() routine to signal some kind of stateful condition variable that will
- // signal whatever blocking primitive the main thread is using, so that it will wake up and execute one
- // more iteration of its loop, and immediately call mDNS_Execute() again. The signal has to be stateful
- // in the sense that if the main thread has not yet entered its blocking primitive, then as soon as it
- // does, the state of the signal will be noticed, causing the blocking primitive to return immediately
- // without blocking. This avoids the race condition between the signal from the other thread arriving
- // just *before* or just *after* the main thread enters the blocking primitive.
- //
- // On multi-threaded systems (like the current Mac OS 9 implementation) that are entirely timer-driven,
- // with no main mDNS_Execute() thread, it is the responsibility of the mDNSPlatformUnlock() routine to
- // set the timer according to the m->NextScheduledEvent value, and then when the timer fires, the timer
- // callback function should call mDNS_Execute() (and ignore the return value, which may already be stale
- // by the time it gets to the timer callback function).
-
- mDNS_Unlock(m); // Calling mDNS_Unlock is what gives m->NextScheduledEvent its new value
- return(m->NextScheduledEvent);
- }
-
mDNSlocal void SuspendLLQs(mDNS *m)
- {
- DNSQuestion *q;
- for (q = m->Questions; q; q = q->next)
- if (ActiveQuestion(q) && !mDNSOpaque16IsZero(q->TargetQID) && q->LongLived && q->state == LLQ_Established)
- { q->ReqLease = 0; sendLLQRefresh(m, q); }
- }
+{
+ DNSQuestion *q;
+ for (q = m->Questions; q; q = q->next)
+ if (ActiveQuestion(q) && !mDNSOpaque16IsZero(q->TargetQID) && q->LongLived && q->state == LLQ_Established)
+ { q->ReqLease = 0; sendLLQRefresh(m, q); }
+}
+#endif // UNICAST_DISABLED
mDNSlocal mDNSBool QuestionHasLocalAnswers(mDNS *const m, DNSQuestion *q)
- {
- AuthRecord *rr;
- mDNSu32 slot;
- AuthGroup *ag;
-
- slot = AuthHashSlot(&q->qname);
- ag = AuthGroupForName(&m->rrauth, slot, q->qnamehash, &q->qname);
- if (ag)
- {
- for (rr = ag->members; rr; rr=rr->next)
- // Filter the /etc/hosts records - LocalOnly, Unique, A/AAAA/CNAME
- if (LORecordAnswersAddressType(rr) && LocalOnlyRecordAnswersQuestion(rr, q))
- {
- LogInfo("QuestionHasLocalAnswers: Question %p %##s (%s) has local answer %s", q, q->qname.c, DNSTypeName(q->qtype), ARDisplayString(m, rr));
- return mDNStrue;
- }
- }
- return mDNSfalse;
- }
+{
+ AuthRecord *rr;
+ mDNSu32 slot;
+ AuthGroup *ag;
+
+ slot = AuthHashSlot(&q->qname);
+ ag = AuthGroupForName(&m->rrauth, slot, q->qnamehash, &q->qname);
+ if (ag)
+ {
+ for (rr = ag->members; rr; rr=rr->next)
+ // Filter the /etc/hosts records - LocalOnly, Unique, A/AAAA/CNAME
+ if (UniqueLocalOnlyRecord(rr) && LocalOnlyRecordAnswersQuestion(rr, q))
+ {
+ LogInfo("QuestionHasLocalAnswers: Question %p %##s (%s) has local answer %s", q, q->qname.c, DNSTypeName(q->qtype), ARDisplayString(m, rr));
+ return mDNStrue;
+ }
+ }
+ return mDNSfalse;
+}
// ActivateUnicastQuery() is called from three places:
// 1. When a new question is created
// In case 1 we don't want to mess with our established ThisQInterval and LastQTime (ScheduleImmediately is false)
// In cases 2 and 3 we do want to cause the question to be resent immediately (ScheduleImmediately is true)
mDNSlocal void ActivateUnicastQuery(mDNS *const m, DNSQuestion *const question, mDNSBool ScheduleImmediately)
- {
- // For now this AutoTunnel stuff is specific to Mac OS X.
- // In the future, if there's demand, we may see if we can abstract it out cleanly into the platform layer
+{
+ // For now this AutoTunnel stuff is specific to Mac OS X.
+ // In the future, if there's demand, we may see if we can abstract it out cleanly into the platform layer
#if APPLE_OSX_mDNSResponder
- // Even though BTMM client tunnels are only useful for AAAA queries, we need to treat v4 and v6 queries equally.
- // Otherwise we can get the situation where the A query completes really fast (with an NXDOMAIN result) and the
- // caller then gives up waiting for the AAAA result while we're still in the process of setting up the tunnel.
- // To level the playing field, we block both A and AAAA queries while tunnel setup is in progress, and then
- // returns results for both at the same time. If we are looking for the _autotunnel6 record, then skip this logic
- // as this would trigger looking up _autotunnel6._autotunnel6 and end up failing the original query.
-
- if (RRTypeIsAddressType(question->qtype) && PrivateQuery(question) &&
- !SameDomainLabel(question->qname.c, (const mDNSu8 *)"\x0c_autotunnel6")&& question->QuestionCallback != AutoTunnelCallback)
- {
- question->NoAnswer = NoAnswer_Suspended;
- AddNewClientTunnel(m, question);
- return;
- }
+ // Even though BTMM client tunnels are only useful for AAAA queries, we need to treat v4 and v6 queries equally.
+ // Otherwise we can get the situation where the A query completes really fast (with an NXDOMAIN result) and the
+ // caller then gives up waiting for the AAAA result while we're still in the process of setting up the tunnel.
+ // To level the playing field, we block both A and AAAA queries while tunnel setup is in progress, and then
+ // returns results for both at the same time. If we are looking for the _autotunnel6 record, then skip this logic
+ // as this would trigger looking up _autotunnel6._autotunnel6 and end up failing the original query.
+
+ if (RRTypeIsAddressType(question->qtype) && PrivateQuery(question) &&
+ !SameDomainLabel(question->qname.c, (const mDNSu8 *)"\x0c_autotunnel6")&& question->QuestionCallback != AutoTunnelCallback)
+ {
+ question->NoAnswer = NoAnswer_Suspended;
+ AddNewClientTunnel(m, question);
+ return;
+ }
#endif // APPLE_OSX_mDNSResponder
- if (!question->DuplicateOf)
- {
- debugf("ActivateUnicastQuery: %##s %s%s%s",
- question->qname.c, DNSTypeName(question->qtype), PrivateQuery(question) ? " (Private)" : "", ScheduleImmediately ? " ScheduleImmediately" : "");
- question->CNAMEReferrals = 0;
- if (question->nta) { CancelGetZoneData(m, question->nta); question->nta = mDNSNULL; }
- if (question->LongLived)
- {
- question->state = LLQ_InitialRequest;
- question->id = zeroOpaque64;
- question->servPort = zeroIPPort;
- if (question->tcp) { DisposeTCPConn(question->tcp); question->tcp = mDNSNULL; }
- }
- // If the question has local answers, then we don't want answers from outside
- if (ScheduleImmediately && !QuestionHasLocalAnswers(m, question))
- {
- question->ThisQInterval = InitialQuestionInterval;
- question->LastQTime = m->timenow - question->ThisQInterval;
- SetNextQueryTime(m, question);
- }
- }
- }
+ if (!question->DuplicateOf)
+ {
+ debugf("ActivateUnicastQuery: %##s %s%s%s",
+ question->qname.c, DNSTypeName(question->qtype), PrivateQuery(question) ? " (Private)" : "", ScheduleImmediately ? " ScheduleImmediately" : "");
+ question->CNAMEReferrals = 0;
+ if (question->nta) { CancelGetZoneData(m, question->nta); question->nta = mDNSNULL; }
+ if (question->LongLived)
+ {
+ question->state = LLQ_InitialRequest;
+ question->id = zeroOpaque64;
+ question->servPort = zeroIPPort;
+ if (question->tcp) { DisposeTCPConn(question->tcp); question->tcp = mDNSNULL; }
+ }
+ // If the question has local answers, then we don't want answers from outside
+ if (ScheduleImmediately && !QuestionHasLocalAnswers(m, question))
+ {
+ question->ThisQInterval = InitialQuestionInterval;
+ question->LastQTime = m->timenow - question->ThisQInterval;
+ SetNextQueryTime(m, question);
+ }
+ }
+}
// Caller should hold the lock
mDNSexport void mDNSCoreRestartAddressQueries(mDNS *const m, mDNSBool SearchDomainsChanged, FlushCache flushCacheRecords,
- CallbackBeforeStartQuery BeforeStartCallback, void *context)
- {
- DNSQuestion *q;
- DNSQuestion *restart = mDNSNULL;
-
- if (!m->mDNS_busy) LogMsg("mDNSCoreRestartAddressQueries: ERROR!! Lock not held");
-
- // 1. Flush the cache records
- if (flushCacheRecords) flushCacheRecords(m);
-
- // 2. Even though we may have purged the cache records above, before it can generate RMV event
- // we are going to stop the question. Hence we need to deliver the RMV event before we
- // stop the question.
- //
- // CurrentQuestion is used by RmvEventsForQuestion below. While delivering RMV events, the
- // application callback can potentially stop the current question (detected by CurrentQuestion) or
- // *any* other question which could be the next one that we may process here. RestartQuestion
- // points to the "next" question which will be automatically advanced in mDNS_StopQuery_internal
- // if the "next" question is stopped while the CurrentQuestion is stopped
-
- if (m->RestartQuestion)
- LogMsg("mDNSCoreRestartAddressQueries: ERROR!! m->RestartQuestion already set: %##s (%s)",
- m->RestartQuestion->qname.c, DNSTypeName(m->RestartQuestion->qtype));
-
- m->RestartQuestion = m->Questions;
- while (m->RestartQuestion)
- {
- q = m->RestartQuestion;
- m->RestartQuestion = q->next;
- // GetZoneData questions are referenced by other questions (original query that started the GetZoneData
- // question) through their "nta" pointer. Normally when the original query stops, it stops the
- // GetZoneData question and also frees the memory (See CancelGetZoneData). If we stop the GetZoneData
- // question followed by the original query that refers to this GetZoneData question, we will end up
- // freeing the GetZoneData question and then start the "freed" question at the end.
-
- if (IsGetZoneDataQuestion(q))
- {
- DNSQuestion *refq = q->next;
- LogInfo("mDNSCoreRestartAddressQueries: Skipping GetZoneDataQuestion %p %##s (%s)", q, q->qname.c, DNSTypeName(q->qtype));
- // debug stuff, we just try to find the referencing question and don't do much with it
- while (refq)
- {
- if (q == &refq->nta->question)
- {
- LogInfo("mDNSCoreRestartAddressQueries: Question %p %##s (%s) referring to GetZoneDataQuestion %p, not stopping", refq, refq->qname.c, DNSTypeName(refq->qtype), q);
- }
- refq = refq->next;
- }
- continue;
- }
-
- // This function is called when /etc/hosts changes and that could affect A, AAAA and CNAME queries
- if (q->qtype != kDNSType_A && q->qtype != kDNSType_AAAA && q->qtype != kDNSType_CNAME) continue;
-
- // If the search domains did not change, then we restart all the queries. Otherwise, only
- // for queries for which we "might" have appended search domains ("might" because we may
- // find results before we apply search domains even though AppendSearchDomains is set to 1)
- if (!SearchDomainsChanged || q->AppendSearchDomains)
- {
- // NOTE: CacheRecordRmvEventsForQuestion will not generate RMV events for queries that have non-zero
- // LOAddressAnswers. Hence it is important that we call CacheRecordRmvEventsForQuestion before
- // LocalRecordRmvEventsForQuestion (which decrements LOAddressAnswers). Let us say that
- // /etc/hosts has an A Record for web.apple.com. Any queries for web.apple.com will be answered locally.
- // But this can't prevent a CNAME/AAAA query to not to be sent on the wire. When it is sent on the wire,
- // it could create cache entries. When we are restarting queries, we can't deliver the cache RMV events
- // for the original query using these cache entries as ADDs were never delivered using these cache
- // entries and hence this order is needed.
-
- // If the query is suppressed, the RMV events won't be delivered
- if (!CacheRecordRmvEventsForQuestion(m, q)) { LogInfo("mDNSCoreRestartAddressQueries: Question deleted while delivering Cache Record RMV events"); continue; }
-
- // SuppressQuery status does not affect questions that are answered using local records
- if (!LocalRecordRmvEventsForQuestion(m, q)) { LogInfo("mDNSCoreRestartAddressQueries: Question deleted while delivering Local Record RMV events"); continue; }
-
- LogInfo("mDNSCoreRestartAddressQueries: Stop question %p %##s (%s), AppendSearchDomains %d, qnameOrig %p", q,
- q->qname.c, DNSTypeName(q->qtype), q->AppendSearchDomains, q->qnameOrig);
- mDNS_StopQuery_internal(m, q);
- // Reset state so that it looks like it was in the beginning i.e it should look at /etc/hosts, cache
- // and then search domains should be appended. At the beginning, qnameOrig was NULL.
- if (q->qnameOrig)
- {
- LogInfo("mDNSCoreRestartAddressQueries: qnameOrig %##s", q->qnameOrig);
- AssignDomainName(&q->qname, q->qnameOrig);
- mDNSPlatformMemFree(q->qnameOrig);
- q->qnameOrig = mDNSNULL;
- q->RetryWithSearchDomains = ApplySearchDomainsFirst(q) ? 1 : 0;
- }
- q->SearchListIndex = 0;
- q->next = restart;
- restart = q;
- }
- }
-
- // 3. Callback before we start the query
- if (BeforeStartCallback) BeforeStartCallback(m, context);
-
- // 4. Restart all the stopped queries
- while (restart)
- {
- q = restart;
- restart = restart->next;
- q->next = mDNSNULL;
- LogInfo("mDNSCoreRestartAddressQueries: Start question %p %##s (%s)", q, q->qname.c, DNSTypeName(q->qtype));
- mDNS_StartQuery_internal(m, q);
- }
- }
+ CallbackBeforeStartQuery BeforeStartCallback, void *context)
+{
+ DNSQuestion *q;
+ DNSQuestion *restart = mDNSNULL;
+
+ mDNS_CheckLock(m);
+
+ // 1. Flush the cache records
+ if (flushCacheRecords) flushCacheRecords(m);
+
+ // 2. Even though we may have purged the cache records above, before it can generate RMV event
+ // we are going to stop the question. Hence we need to deliver the RMV event before we
+ // stop the question.
+ //
+ // CurrentQuestion is used by RmvEventsForQuestion below. While delivering RMV events, the
+ // application callback can potentially stop the current question (detected by CurrentQuestion) or
+ // *any* other question which could be the next one that we may process here. RestartQuestion
+ // points to the "next" question which will be automatically advanced in mDNS_StopQuery_internal
+ // if the "next" question is stopped while the CurrentQuestion is stopped
+
+ if (m->RestartQuestion)
+ LogMsg("mDNSCoreRestartAddressQueries: ERROR!! m->RestartQuestion already set: %##s (%s)",
+ m->RestartQuestion->qname.c, DNSTypeName(m->RestartQuestion->qtype));
+
+ m->RestartQuestion = m->Questions;
+ while (m->RestartQuestion)
+ {
+ q = m->RestartQuestion;
+ m->RestartQuestion = q->next;
+ // GetZoneData questions are referenced by other questions (original query that started the GetZoneData
+ // question) through their "nta" pointer. Normally when the original query stops, it stops the
+ // GetZoneData question and also frees the memory (See CancelGetZoneData). If we stop the GetZoneData
+ // question followed by the original query that refers to this GetZoneData question, we will end up
+ // freeing the GetZoneData question and then start the "freed" question at the end.
+
+ if (IsGetZoneDataQuestion(q))
+ {
+ DNSQuestion *refq = q->next;
+ LogInfo("mDNSCoreRestartAddressQueries: Skipping GetZoneDataQuestion %p %##s (%s)", q, q->qname.c, DNSTypeName(q->qtype));
+ // debug stuff, we just try to find the referencing question and don't do much with it
+ while (refq)
+ {
+ if (q == &refq->nta->question)
+ {
+ LogInfo("mDNSCoreRestartAddressQueries: Question %p %##s (%s) referring to GetZoneDataQuestion %p, not stopping", refq, refq->qname.c, DNSTypeName(refq->qtype), q);
+ }
+ refq = refq->next;
+ }
+ continue;
+ }
+
+ // This function is called when /etc/hosts changes and that could affect A, AAAA and CNAME queries
+ if (q->qtype != kDNSType_A && q->qtype != kDNSType_AAAA && q->qtype != kDNSType_CNAME) continue;
+
+ // If the search domains did not change, then we restart all the queries. Otherwise, only
+ // for queries for which we "might" have appended search domains ("might" because we may
+ // find results before we apply search domains even though AppendSearchDomains is set to 1)
+ if (!SearchDomainsChanged || q->AppendSearchDomains)
+ {
+ // NOTE: CacheRecordRmvEventsForQuestion will not generate RMV events for queries that have non-zero
+ // LOAddressAnswers. Hence it is important that we call CacheRecordRmvEventsForQuestion before
+ // LocalRecordRmvEventsForQuestion (which decrements LOAddressAnswers). Let us say that
+ // /etc/hosts has an A Record for web.apple.com. Any queries for web.apple.com will be answered locally.
+ // But this can't prevent a CNAME/AAAA query to not to be sent on the wire. When it is sent on the wire,
+ // it could create cache entries. When we are restarting queries, we can't deliver the cache RMV events
+ // for the original query using these cache entries as ADDs were never delivered using these cache
+ // entries and hence this order is needed.
+
+ // If the query is suppressed, the RMV events won't be delivered
+ if (!CacheRecordRmvEventsForQuestion(m, q)) { LogInfo("mDNSCoreRestartAddressQueries: Question deleted while delivering Cache Record RMV events"); continue; }
+
+ // SuppressQuery status does not affect questions that are answered using local records
+ if (!LocalRecordRmvEventsForQuestion(m, q)) { LogInfo("mDNSCoreRestartAddressQueries: Question deleted while delivering Local Record RMV events"); continue; }
+
+ LogInfo("mDNSCoreRestartAddressQueries: Stop question %p %##s (%s), AppendSearchDomains %d, qnameOrig %p", q,
+ q->qname.c, DNSTypeName(q->qtype), q->AppendSearchDomains, q->qnameOrig);
+ mDNS_StopQuery_internal(m, q);
+ // Reset state so that it looks like it was in the beginning i.e it should look at /etc/hosts, cache
+ // and then search domains should be appended. At the beginning, qnameOrig was NULL.
+ if (q->qnameOrig)
+ {
+ LogInfo("mDNSCoreRestartAddressQueries: qnameOrig %##s", q->qnameOrig);
+ AssignDomainName(&q->qname, q->qnameOrig);
+ mDNSPlatformMemFree(q->qnameOrig);
+ q->qnameOrig = mDNSNULL;
+ q->RetryWithSearchDomains = ApplySearchDomainsFirst(q) ? 1 : 0;
+ }
+ q->SearchListIndex = 0;
+ q->next = restart;
+ restart = q;
+ }
+ }
+
+ // 3. Callback before we start the query
+ if (BeforeStartCallback) BeforeStartCallback(m, context);
+
+ // 4. Restart all the stopped queries
+ while (restart)
+ {
+ q = restart;
+ restart = restart->next;
+ q->next = mDNSNULL;
+ LogInfo("mDNSCoreRestartAddressQueries: Start question %p %##s (%s)", q, q->qname.c, DNSTypeName(q->qtype));
+ mDNS_StartQuery_internal(m, q);
+ }
+}
mDNSexport void mDNSCoreRestartQueries(mDNS *const m)
- {
- DNSQuestion *q;
+{
+ DNSQuestion *q;
#ifndef UNICAST_DISABLED
- // Retrigger all our uDNS questions
- if (m->CurrentQuestion)
- LogMsg("mDNSCoreRestartQueries: ERROR m->CurrentQuestion already set: %##s (%s)",
- m->CurrentQuestion->qname.c, DNSTypeName(m->CurrentQuestion->qtype));
- m->CurrentQuestion = m->Questions;
- while (m->CurrentQuestion)
- {
- q = m->CurrentQuestion;
- m->CurrentQuestion = m->CurrentQuestion->next;
- if (!mDNSOpaque16IsZero(q->TargetQID) && ActiveQuestion(q)) ActivateUnicastQuery(m, q, mDNStrue);
- }
+ // Retrigger all our uDNS questions
+ if (m->CurrentQuestion)
+ LogMsg("mDNSCoreRestartQueries: ERROR m->CurrentQuestion already set: %##s (%s)",
+ m->CurrentQuestion->qname.c, DNSTypeName(m->CurrentQuestion->qtype));
+ m->CurrentQuestion = m->Questions;
+ while (m->CurrentQuestion)
+ {
+ q = m->CurrentQuestion;
+ m->CurrentQuestion = m->CurrentQuestion->next;
+ if (!mDNSOpaque16IsZero(q->TargetQID) && ActiveQuestion(q)) ActivateUnicastQuery(m, q, mDNStrue);
+ }
#endif
- // Retrigger all our mDNS questions
- for (q = m->Questions; q; q=q->next) // Scan our list of questions
- if (mDNSOpaque16IsZero(q->TargetQID) && ActiveQuestion(q))
- {
- q->ThisQInterval = InitialQuestionInterval; // MUST be > zero for an active question
- q->RequestUnicast = 2; // Set to 2 because is decremented once *before* we check it
- q->LastQTime = m->timenow - q->ThisQInterval;
- q->RecentAnswerPkts = 0;
- ExpireDupSuppressInfo(q->DupSuppress, m->timenow);
- m->NextScheduledQuery = m->timenow;
- }
- }
+ // Retrigger all our mDNS questions
+ for (q = m->Questions; q; q=q->next) // Scan our list of questions
+ mDNSCoreRestartQuestion(m, q);
+}
+
+// restart question if it's multicast and currently active
+mDNSexport void mDNSCoreRestartQuestion(mDNS *const m, DNSQuestion *q)
+{
+ if (mDNSOpaque16IsZero(q->TargetQID) && ActiveQuestion(q))
+ {
+ q->ThisQInterval = InitialQuestionInterval; // MUST be > zero for an active question
+#if mDNS_REQUEST_UNICAST_RESPONSE
+ q->RequestUnicast = SET_QU_IN_FIRST_FOUR_QUERIES;
+#else // mDNS_REQUEST_UNICAST_RESPONSE
+ q->RequestUnicast = SET_QU_IN_FIRST_QUERY;
+#endif // mDNS_REQUEST_UNICAST_RESPONSE
+ q->LastQTime = m->timenow - q->ThisQInterval;
+ q->RecentAnswerPkts = 0;
+ ExpireDupSuppressInfo(q->DupSuppress, m->timenow);
+ m->NextScheduledQuery = m->timenow;
+ }
+}
+
+// restart the probe/announce cycle for multicast record
+mDNSexport void mDNSCoreRestartRegistration(mDNS *const m, AuthRecord *rr, int announceCount)
+{
+ if (!AuthRecord_uDNS(rr))
+ {
+ if (rr->resrec.RecordType == kDNSRecordTypeVerified && !rr->DependentOn) rr->resrec.RecordType = kDNSRecordTypeUnique;
+ rr->ProbeCount = DefaultProbeCountForRecordType(rr->resrec.RecordType);
+
+ // announceCount < 0 indicates default announce count should be used
+ if (announceCount < 0)
+ announceCount = InitialAnnounceCount;
+ if (rr->AnnounceCount < announceCount)
+ rr->AnnounceCount = announceCount;
+
+ if (mDNS_KeepaliveRecord(&rr->resrec))
+ rr->AnnounceCount = 0; // Do not announce keepalive records
+ else
+ rr->AnnounceCount = InitialAnnounceCount;
+ rr->SendNSECNow = mDNSNULL;
+ InitializeLastAPTime(m, rr);
+ }
+}
// ***************************************************************************
#if COMPILER_LIKES_PRAGMA_MARK
#endif
mDNSexport void mDNS_UpdateAllowSleep(mDNS *const m)
- {
+{
#ifndef IDLESLEEPCONTROL_DISABLED
- mDNSBool allowSleep = mDNStrue;
- char reason[128];
-
- reason[0] = 0;
-
- if (m->SystemSleepOnlyIfWakeOnLAN)
- {
- // Don't sleep if we are a proxy for any services
- if (m->ProxyRecords)
- {
- allowSleep = mDNSfalse;
- mDNS_snprintf(reason, sizeof(reason), "sleep proxy for %d records", m->ProxyRecords);
- LogInfo("Sleep disabled because we are proxying %d records", m->ProxyRecords);
- }
-
- if (allowSleep && mDNSCoreHaveAdvertisedMulticastServices(m))
- {
- // Scan the list of active interfaces
- NetworkInterfaceInfo *intf;
- for (intf = GetFirstActiveInterface(m->HostInterfaces); intf; intf = GetFirstActiveInterface(intf->next))
- {
- if (intf->McastTxRx && !intf->Loopback)
- {
- // Disallow sleep if this interface doesn't support NetWake
- if (!intf->NetWake)
- {
- allowSleep = mDNSfalse;
- mDNS_snprintf(reason, sizeof(reason), "%s does not support NetWake", intf->ifname);
- LogInfo("Sleep disabled because %s does not support NetWake", intf->ifname);
- break;
- }
-
- // Disallow sleep if there is no sleep proxy server
- if (FindSPSInCache1(m, &intf->NetWakeBrowse, mDNSNULL, mDNSNULL) == mDNSNULL)
- {
- allowSleep = mDNSfalse;
- mDNS_snprintf(reason, sizeof(reason), "%s does not support NetWake", intf->ifname);
- LogInfo("Sleep disabled because %s has no sleep proxy", intf->ifname);
- break;
- }
- }
- }
- }
- }
-
- // Call the platform code to enable/disable sleep
- mDNSPlatformSetAllowSleep(m, allowSleep, reason);
+ mDNSBool allowSleep = mDNStrue;
+ char reason[128];
+
+ reason[0] = 0;
+
+ if (m->SystemSleepOnlyIfWakeOnLAN)
+ {
+ // Don't sleep if we are a proxy for any services
+ if (m->ProxyRecords)
+ {
+ allowSleep = mDNSfalse;
+ mDNS_snprintf(reason, sizeof(reason), "sleep proxy for %d records", m->ProxyRecords);
+ LogInfo("mDNS_UpdateAllowSleep: Sleep disabled because we are proxying %d records", m->ProxyRecords);
+ }
+
+ if (allowSleep && mDNSCoreHaveAdvertisedMulticastServices(m))
+ {
+ // Scan the list of active interfaces
+ NetworkInterfaceInfo *intf;
+ for (intf = GetFirstActiveInterface(m->HostInterfaces); intf; intf = GetFirstActiveInterface(intf->next))
+ {
+ if (intf->McastTxRx && !intf->Loopback && !mDNSPlatformInterfaceIsD2D(intf->InterfaceID))
+ {
+ // Disallow sleep if this interface doesn't support NetWake
+ if (!intf->NetWake)
+ {
+ allowSleep = mDNSfalse;
+ mDNS_snprintf(reason, sizeof(reason), "%s does not support NetWake", intf->ifname);
+ LogInfo("mDNS_UpdateAllowSleep: Sleep disabled because %s does not support NetWake", intf->ifname);
+ break;
+ }
+
+ // Disallow sleep if there is no sleep proxy server
+ const CacheRecord *cr = FindSPSInCache1(m, &intf->NetWakeBrowse, mDNSNULL, mDNSNULL);
+ if ( cr == mDNSNULL)
+ {
+ allowSleep = mDNSfalse;
+ mDNS_snprintf(reason, sizeof(reason), "No sleep proxy server on %s", intf->ifname);
+ LogInfo("mDNS_UpdateAllowSleep: Sleep disabled because %s has no sleep proxy server", intf->ifname);
+ break;
+ }
+ else if (m->SPSType != 0)
+ {
+ mDNSu32 mymetric = LocalSPSMetric(m);
+ mDNSu32 metric = SPSMetric(cr->resrec.rdata->u.name.c);
+ if (metric >= mymetric)
+ {
+ allowSleep = mDNSfalse;
+ mDNS_snprintf(reason, sizeof(reason), "No sleep proxy server with better metric on %s", intf->ifname);
+ LogInfo("mDNS_UpdateAllowSleep: Sleep disabled because %s has no sleep proxy server with a better metric", intf->ifname);
+ break;
+ }
+ }
+ }
+ }
+ }
+ }
+
+ // Call the platform code to enable/disable sleep
+ mDNSPlatformSetAllowSleep(m, allowSleep, reason);
+#else
+ (void) m;
#endif /* !defined(IDLESLEEPCONTROL_DISABLED) */
- }
+}
+
+mDNSlocal mDNSBool mDNSUpdateOkToSend(mDNS *const m, AuthRecord *rr, NetworkInterfaceInfo *const intf, mDNSu32 scopeid)
+{
+ // If it is not a uDNS record, check to see if the updateid is zero. "updateid" is cleared when we have
+ // sent the resource record on all the interfaces. If the update id is not zero, check to see if it is time
+ // to send.
+ if (AuthRecord_uDNS(rr) || (rr->AuthFlags & AuthFlagsWakeOnly) || mDNSOpaque16IsZero(rr->updateid) ||
+ m->timenow - (rr->LastAPTime + rr->ThisAPInterval) < 0)
+ {
+ return mDNSfalse;
+ }
+
+ // If we have a pending registration for "scopeid", it is ok to send the update on that interface.
+ // If the scopeid is too big to check for validity, we don't check against updateIntID. When
+ // we successfully update on all the interfaces (with whatever set in "rr->updateIntID"), we clear
+ // updateid and we should have returned from above.
+ //
+ // Note: scopeid is the same as intf->InterfaceID. It is passed in so that we don't have to call the
+ // platform function to extract the value from "intf" everytime.
+
+ if ((scopeid >= (sizeof(rr->updateIntID) * mDNSNBBY) || bit_get_opaque64(rr->updateIntID, scopeid)) &&
+ (!rr->resrec.InterfaceID || rr->resrec.InterfaceID == intf->InterfaceID))
+ return mDNStrue;
+
+ return mDNSfalse;
+}
+
+mDNSexport void UpdateRMACCallback(mDNS *const m, void *context)
+{
+ IPAddressMACMapping *addrmap = (IPAddressMACMapping *)context ;
+ m->CurrentRecord = m->ResourceRecords;
+
+ if (!addrmap)
+ {
+ LogMsg("UpdateRMACCallback: Address mapping is NULL");
+ return;
+ }
+
+ while (m->CurrentRecord)
+ {
+ AuthRecord *rr = m->CurrentRecord;
+ // If this is a keepalive record and the remote IP address matches, update the RData
+ if (mDNS_KeepaliveRecord(&rr->resrec))
+ {
+ mDNSAddr raddr;
+ getKeepaliveRaddr(m, rr, &raddr);
+ if (mDNSSameAddress(&raddr, &addrmap->ipaddr))
+ {
+ UpdateKeepaliveRData(m, rr, mDNSNULL, mDNStrue, (char *)(addrmap->ethaddr));
+ }
+ }
+ m->CurrentRecord = rr->next;
+ }
+
+ if (addrmap)
+ {
+ mDNSPlatformMemFree(addrmap);
+ }
+}
+
+mDNSexport mStatus UpdateKeepaliveRData(mDNS *const m, AuthRecord *rr, NetworkInterfaceInfo *const intf, mDNSBool updateMac, char *ethAddr)
+{
+ mDNSu16 newrdlength;
+ mDNSAddr laddr, raddr;
+ mDNSEthAddr eth;
+ mDNSIPPort lport, rport;
+ mDNSu32 timeout, seq, ack;
+ mDNSu16 win;
+ UTF8str255 txt;
+ int rdsize;
+ RData *newrd;
+ mDNSTCPInfo mti;
+ mStatus ret;
+
+ // Note: If we fail to update the DNS NULL record with additional information in this function, it will be registered
+ // with the SPS like any other record. SPS will not send keepalives if it does not have additional information.
+ mDNS_ExtractKeepaliveInfo(rr, &timeout, &laddr, &raddr, ð, &seq, &ack, &lport, &rport, &win);
+ if (!timeout || mDNSAddressIsZero(&laddr) || mDNSAddressIsZero(&raddr) || mDNSIPPortIsZero(lport) ||
+ mDNSIPPortIsZero(rport))
+ {
+ LogMsg("UpdateKeepaliveRData: not a valid record %s for keepalive %#a:%d %#a:%d", ARDisplayString(m, rr), &laddr, lport.NotAnInteger, &raddr, rport.NotAnInteger);
+ return mStatus_UnknownErr;
+ }
+
+ if (updateMac)
+ {
+ if (laddr.type == mDNSAddrType_IPv4)
+ newrdlength = mDNS_snprintf((char *)&txt.c[1], sizeof(txt.c) - 1, "t=%d i=%d c=%d h=%#a d=%#a l=%u r=%u m=%s", timeout, kKeepaliveRetryInterval, kKeepaliveRetryCount, &laddr, &raddr, mDNSVal16(lport), mDNSVal16(rport), ethAddr);
+ else
+ newrdlength = mDNS_snprintf((char *)&txt.c[1], sizeof(txt.c) - 1, "t=%d i=%d c=%d H=%#a D=%#a l=%u r=%u m=%s", timeout, kKeepaliveRetryInterval, kKeepaliveRetryCount, &laddr, &raddr, mDNSVal16(lport), mDNSVal16(rport), ethAddr);
+
+ }
+ else
+ {
+ // If this keepalive packet would be sent on a different interface than the current one that we are processing
+ // now, then we don't update the DNS NULL record. But we do not prevent it from registering with the SPS. When SPS sees
+ // this DNS NULL record, it does not send any keepalives as it does not have all the information
+ mDNSPlatformMemZero(&mti, sizeof (mDNSTCPInfo));
+ ret = mDNSPlatformRetrieveTCPInfo(m, &laddr, &lport, &raddr, &rport, &mti);
+ if (ret != mStatus_NoError)
+ {
+ LogMsg("mDNSPlatformRetrieveTCPInfo: mDNSPlatformRetrieveTCPInfo failed %d", ret);
+ return ret;
+ }
+ if ((intf != mDNSNULL) && (mti.IntfId != intf->InterfaceID))
+ {
+ LogInfo("mDNSPlatformRetrieveTCPInfo: InterfaceID mismatch mti.IntfId = %p InterfaceID = %p", mti.IntfId, intf->InterfaceID);
+ return mStatus_BadParamErr;
+ }
+
+ if (laddr.type == mDNSAddrType_IPv4)
+ newrdlength = mDNS_snprintf((char *)&txt.c[1], sizeof(txt.c) - 1, "t=%d i=%d c=%d h=%#a d=%#a l=%u r=%u m=%.6a s=%u a=%u w=%u", timeout, kKeepaliveRetryInterval, kKeepaliveRetryCount, &laddr, &raddr, mDNSVal16(lport), mDNSVal16(rport), ð, mti.seq, mti.ack, mti.window);
+ else
+ newrdlength = mDNS_snprintf((char *)&txt.c[1], sizeof(txt.c) - 1, "t=%d i=%d c=%d H=%#a D=%#a l=%u r=%u m=%.6a s=%u a=%u w=%u", timeout, kKeepaliveRetryInterval, kKeepaliveRetryCount, &laddr, &raddr, mDNSVal16(lport), mDNSVal16(rport), ð, mti.seq, mti.ack, mti.window);
+ }
+
+ // Did we insert a null byte at the end ?
+ if (newrdlength == (sizeof(txt.c) - 1))
+ {
+ LogMsg("UpdateKeepaliveRData: could not allocate memory %s", ARDisplayString(m, rr));
+ return mStatus_NoMemoryErr;
+ }
+
+ // Include the length for the null byte at the end
+ txt.c[0] = newrdlength + 1;
+ // Account for the first length byte and the null byte at the end
+ newrdlength += 2;
+
+ rdsize = newrdlength > sizeof(RDataBody) ? newrdlength : sizeof(RDataBody);
+ newrd = mDNSPlatformMemAllocate(sizeof(RData) - sizeof(RDataBody) + rdsize);
+ if (!newrd) { LogMsg("UpdateKeepaliveRData: ptr NULL"); return mStatus_NoMemoryErr; }
+
+ newrd->MaxRDLength = (mDNSu16) rdsize;
+ mDNSPlatformMemCopy(&newrd->u, txt.c, newrdlength);
+
+ // If we are updating the record for the first time, rdata points to rdatastorage as the rdata memory
+ // was allocated as part of the AuthRecord itself. We allocate memory when we update the AuthRecord.
+ // If the resource record has data that we allocated in a previous pass (to update MAC address),
+ // free that memory here before copying in the new data.
+ if ( rr->resrec.rdata != &rr->rdatastorage)
+ {
+ mDNSPlatformMemFree(rr->resrec.rdata);
+ LogSPS("UpdateKeepaliveRData: Freed allocated memory for keep alive packet: %s ", ARDisplayString(m, rr));
+ }
+ SetNewRData(&rr->resrec, newrd, newrdlength); // Update our rdata
+
+ LogSPS("UpdateKeepaliveRData: successfully updated the record %s", ARDisplayString(m, rr));
+ return mStatus_NoError;
+}
mDNSlocal void SendSPSRegistrationForOwner(mDNS *const m, NetworkInterfaceInfo *const intf, const mDNSOpaque16 id, const OwnerOptData *const owner)
- {
- const int optspace = DNSOpt_Header_Space + DNSOpt_LeaseData_Space + DNSOpt_Owner_Space(&m->PrimaryMAC, &intf->MAC);
- const int sps = intf->NextSPSAttempt / 3;
- AuthRecord *rr;
-
- if (!intf->SPSAddr[sps].type)
- {
- intf->NextSPSAttemptTime = m->timenow + mDNSPlatformOneSecond;
- if (m->NextScheduledSPRetry - intf->NextSPSAttemptTime > 0)
- m->NextScheduledSPRetry = intf->NextSPSAttemptTime;
- LogSPS("SendSPSRegistration: %s SPS %d (%d) %##s not yet resolved", intf->ifname, intf->NextSPSAttempt, sps, intf->NetWakeResolve[sps].qname.c);
- goto exit;
- }
-
- // Mark our mDNS records (not unicast records) for transfer to SPS
- if (mDNSOpaque16IsZero(id))
- for (rr = m->ResourceRecords; rr; rr=rr->next)
- if (rr->resrec.RecordType > kDNSRecordTypeDeregistering)
- if (rr->resrec.InterfaceID == intf->InterfaceID || (!rr->resrec.InterfaceID && (rr->ForceMCast || IsLocalDomain(rr->resrec.name))))
- if (mDNSPlatformMemSame(owner, &rr->WakeUp, sizeof(*owner)))
- rr->SendRNow = mDNSInterfaceMark; // mark it now
-
- while (1)
- {
- mDNSu8 *p = m->omsg.data;
- // To comply with RFC 2782, PutResourceRecord suppresses name compression for SRV records in unicast updates.
- // For now we follow that same logic for SPS registrations too.
- // If we decide to compress SRV records in SPS registrations in the future, we can achieve that by creating our
- // initial DNSMessage with h.flags set to zero, and then update it to UpdateReqFlags right before sending the packet.
- InitializeDNSMessage(&m->omsg.h, mDNSOpaque16IsZero(id) ? mDNS_NewMessageID(m) : id, UpdateReqFlags);
-
- for (rr = m->ResourceRecords; rr; rr=rr->next)
- if (rr->SendRNow || (!mDNSOpaque16IsZero(id) && !AuthRecord_uDNS(rr) && mDNSSameOpaque16(rr->updateid, id) && m->timenow - (rr->LastAPTime + rr->ThisAPInterval) >= 0))
- if (mDNSPlatformMemSame(owner, &rr->WakeUp, sizeof(*owner)))
- {
- mDNSu8 *newptr;
- const mDNSu8 *const limit = m->omsg.data + (m->omsg.h.mDNS_numUpdates ? NormalMaxDNSMessageData : AbsoluteMaxDNSMessageData) - optspace;
- if (rr->resrec.RecordType & kDNSRecordTypeUniqueMask)
- rr->resrec.rrclass |= kDNSClass_UniqueRRSet; // Temporarily set the 'unique' bit so PutResourceRecord will set it
- newptr = PutResourceRecordTTLWithLimit(&m->omsg, p, &m->omsg.h.mDNS_numUpdates, &rr->resrec, rr->resrec.rroriginalttl, limit);
- rr->resrec.rrclass &= ~kDNSClass_UniqueRRSet; // Make sure to clear 'unique' bit back to normal state
- if (!newptr)
- LogSPS("SendSPSRegistration put %s FAILED %d/%d %s", intf->ifname, p - m->omsg.data, limit - m->omsg.data, ARDisplayString(m, rr));
- else
- {
- LogSPS("SendSPSRegistration put %s %s", intf->ifname, ARDisplayString(m, rr));
- rr->SendRNow = mDNSNULL;
- rr->ThisAPInterval = mDNSPlatformOneSecond;
- rr->LastAPTime = m->timenow;
- rr->updateid = m->omsg.h.id;
- if (m->NextScheduledResponse - (rr->LastAPTime + rr->ThisAPInterval) >= 0)
- m->NextScheduledResponse = (rr->LastAPTime + rr->ThisAPInterval);
- p = newptr;
- }
- }
-
- if (!m->omsg.h.mDNS_numUpdates) break;
- else
- {
- AuthRecord opt;
- mDNS_SetupResourceRecord(&opt, mDNSNULL, mDNSInterface_Any, kDNSType_OPT, kStandardTTL, kDNSRecordTypeKnownUnique, AuthRecordAny, mDNSNULL, mDNSNULL);
- opt.resrec.rrclass = NormalMaxDNSMessageData;
- opt.resrec.rdlength = sizeof(rdataOPT) * 2; // Two options in this OPT record
- opt.resrec.rdestimate = sizeof(rdataOPT) * 2;
- opt.resrec.rdata->u.opt[0].opt = kDNSOpt_Lease;
- opt.resrec.rdata->u.opt[0].optlen = DNSOpt_LeaseData_Space - 4;
- opt.resrec.rdata->u.opt[0].u.updatelease = DEFAULT_UPDATE_LEASE;
- if (!owner->HMAC.l[0]) // If no owner data,
- SetupOwnerOpt(m, intf, &opt.resrec.rdata->u.opt[1]); // use our own interface information
- else // otherwise, use the owner data we were given
- {
- opt.resrec.rdata->u.opt[1].u.owner = *owner;
- opt.resrec.rdata->u.opt[1].opt = kDNSOpt_Owner;
- opt.resrec.rdata->u.opt[1].optlen = DNSOpt_Owner_Space(&owner->HMAC, &owner->IMAC) - 4;
- }
- LogSPS("SendSPSRegistration put %s %s", intf->ifname, ARDisplayString(m, &opt));
- p = PutResourceRecordTTLWithLimit(&m->omsg, p, &m->omsg.h.numAdditionals, &opt.resrec, opt.resrec.rroriginalttl, m->omsg.data + AbsoluteMaxDNSMessageData);
- if (!p)
- LogMsg("SendSPSRegistration: Failed to put OPT record (%d updates) %s", m->omsg.h.mDNS_numUpdates, ARDisplayString(m, &opt));
- else
- {
- mStatus err;
-
- LogSPS("SendSPSRegistration: Sending Update %s %d (%d) id %5d with %d records %d bytes to %#a:%d", intf->ifname, intf->NextSPSAttempt, sps,
- mDNSVal16(m->omsg.h.id), m->omsg.h.mDNS_numUpdates, p - m->omsg.data, &intf->SPSAddr[sps], mDNSVal16(intf->SPSPort[sps]));
- // if (intf->NextSPSAttempt < 5) m->omsg.h.flags = zeroID; // For simulating packet loss
- err = mDNSSendDNSMessage(m, &m->omsg, p, intf->InterfaceID, mDNSNULL, &intf->SPSAddr[sps], intf->SPSPort[sps], mDNSNULL, mDNSNULL);
- if (err) LogSPS("SendSPSRegistration: mDNSSendDNSMessage err %d", err);
- if (err && intf->SPSAddr[sps].type == mDNSAddrType_IPv6 && intf->NetWakeResolve[sps].ThisQInterval == -1)
- {
- LogSPS("SendSPSRegistration %d %##s failed to send to IPv6 address; will try IPv4 instead", sps, intf->NetWakeResolve[sps].qname.c);
- intf->NetWakeResolve[sps].qtype = kDNSType_A;
- mDNS_StartQuery_internal(m, &intf->NetWakeResolve[sps]);
- return;
- }
- }
- }
- }
-
- intf->NextSPSAttemptTime = m->timenow + mDNSPlatformOneSecond * 10; // If successful, update NextSPSAttemptTime
+{
+ const int optspace = DNSOpt_Header_Space + DNSOpt_LeaseData_Space + DNSOpt_Owner_Space(&m->PrimaryMAC, &intf->MAC);
+ const int sps = intf->NextSPSAttempt / 3;
+ AuthRecord *rr;
+ mDNSOpaque16 msgid;
+ mDNSu32 scopeid;
+
+ scopeid = mDNSPlatformInterfaceIndexfromInterfaceID(m, intf->InterfaceID, mDNStrue);
+ if (!intf->SPSAddr[sps].type)
+ {
+ intf->NextSPSAttemptTime = m->timenow + mDNSPlatformOneSecond;
+ if (m->NextScheduledSPRetry - intf->NextSPSAttemptTime > 0)
+ m->NextScheduledSPRetry = intf->NextSPSAttemptTime;
+ LogSPS("SendSPSRegistration: %s SPS %d (%d) %##s not yet resolved", intf->ifname, intf->NextSPSAttempt, sps, intf->NetWakeResolve[sps].qname.c);
+ goto exit;
+ }
+
+ // Mark our mDNS records (not unicast records) for transfer to SPS
+ if (mDNSOpaque16IsZero(id))
+ {
+ // We may have to register this record over multiple interfaces and we don't want to
+ // overwrite the id. We send the registration over interface X with id "IDX" and before
+ // we get a response, we overwrite with id "IDY" for interface Y and we won't accept responses
+ // for "IDX". Hence, we want to use the same ID across all interfaces.
+ //
+ // In the case of sleep proxy server transfering its records when it goes to sleep, the owner
+ // option check below will set the same ID across the records from the same owner. Records
+ // with different owner option gets different ID.
+ msgid = mDNS_NewMessageID(m);
+ for (rr = m->ResourceRecords; rr; rr=rr->next)
+ {
+ if (!(rr->AuthFlags & AuthFlagsWakeOnly) && rr->resrec.RecordType > kDNSRecordTypeDeregistering)
+ {
+ if (rr->resrec.InterfaceID == intf->InterfaceID || (!rr->resrec.InterfaceID && (rr->ForceMCast || IsLocalDomain(rr->resrec.name))))
+ {
+ if (mDNSPlatformMemSame(owner, &rr->WakeUp, sizeof(*owner)))
+ {
+ rr->SendRNow = mDNSInterfaceMark; // mark it now
+ // When we are registering on the first interface, rr->updateid is zero in which case
+ // initialize with the new ID. For subsequent interfaces, we want to use the same ID.
+ // At the end, all the updates sent across all the interfaces with the same ID.
+ if (mDNSOpaque16IsZero(rr->updateid))
+ rr->updateid = msgid;
+ else
+ msgid = rr->updateid;
+ }
+ }
+ }
+ }
+ }
+ else
+ msgid = id;
+
+ while (1)
+ {
+ mDNSu8 *p = m->omsg.data;
+ // To comply with RFC 2782, PutResourceRecord suppresses name compression for SRV records in unicast updates.
+ // For now we follow that same logic for SPS registrations too.
+ // If we decide to compress SRV records in SPS registrations in the future, we can achieve that by creating our
+ // initial DNSMessage with h.flags set to zero, and then update it to UpdateReqFlags right before sending the packet.
+ InitializeDNSMessage(&m->omsg.h, msgid, UpdateReqFlags);
+
+ for (rr = m->ResourceRecords; rr; rr=rr->next)
+ if (rr->SendRNow || mDNSUpdateOkToSend(m, rr, intf, scopeid))
+ {
+ if (mDNSPlatformMemSame(owner, &rr->WakeUp, sizeof(*owner)))
+ {
+ mDNSu8 *newptr;
+ const mDNSu8 *const limit = m->omsg.data + (m->omsg.h.mDNS_numUpdates ? NormalMaxDNSMessageData : AbsoluteMaxDNSMessageData) - optspace;
+
+ // If we can't update the keepalive record, don't send it
+ if (mDNS_KeepaliveRecord(&rr->resrec) && (UpdateKeepaliveRData(m, rr, intf, mDNSfalse, mDNSNULL) != mStatus_NoError))
+ {
+ if (scopeid < (sizeof(rr->updateIntID) * mDNSNBBY))
+ {
+ bit_clr_opaque64(rr->updateIntID, scopeid);
+ }
+ rr->SendRNow = mDNSNULL;
+ continue;
+ }
+
+ if (rr->resrec.RecordType & kDNSRecordTypeUniqueMask)
+ rr->resrec.rrclass |= kDNSClass_UniqueRRSet; // Temporarily set the 'unique' bit so PutResourceRecord will set it
+ newptr = PutResourceRecordTTLWithLimit(&m->omsg, p, &m->omsg.h.mDNS_numUpdates, &rr->resrec, rr->resrec.rroriginalttl, limit);
+ rr->resrec.rrclass &= ~kDNSClass_UniqueRRSet; // Make sure to clear 'unique' bit back to normal state
+ if (!newptr)
+ LogSPS("SendSPSRegistration put %s FAILED %d/%d %s", intf->ifname, p - m->omsg.data, limit - m->omsg.data, ARDisplayString(m, rr));
+ else
+ {
+ LogSPS("SendSPSRegistration put %s 0x%x 0x%x (updateid %d) %s", intf->ifname, rr->updateIntID.l[1], rr->updateIntID.l[0], mDNSVal16(m->omsg.h.id), ARDisplayString(m, rr));
+ rr->SendRNow = mDNSNULL;
+ rr->ThisAPInterval = mDNSPlatformOneSecond;
+ rr->LastAPTime = m->timenow;
+ // should be initialized above
+ if (mDNSOpaque16IsZero(rr->updateid)) LogMsg("SendSPSRegistration: ERROR!! rr %s updateid is zero", ARDisplayString(m, rr));
+ if (m->NextScheduledResponse - (rr->LastAPTime + rr->ThisAPInterval) >= 0)
+ m->NextScheduledResponse = (rr->LastAPTime + rr->ThisAPInterval);
+ p = newptr;
+ }
+ }
+ }
+
+ if (!m->omsg.h.mDNS_numUpdates) break;
+ else
+ {
+ AuthRecord opt;
+ mDNS_SetupResourceRecord(&opt, mDNSNULL, mDNSInterface_Any, kDNSType_OPT, kStandardTTL, kDNSRecordTypeKnownUnique, AuthRecordAny, mDNSNULL, mDNSNULL);
+ opt.resrec.rrclass = NormalMaxDNSMessageData;
+ opt.resrec.rdlength = sizeof(rdataOPT) * 2; // Two options in this OPT record
+ opt.resrec.rdestimate = sizeof(rdataOPT) * 2;
+ opt.resrec.rdata->u.opt[0].opt = kDNSOpt_Lease;
+ opt.resrec.rdata->u.opt[0].optlen = DNSOpt_LeaseData_Space - 4;
+ opt.resrec.rdata->u.opt[0].u.updatelease = DEFAULT_UPDATE_LEASE;
+ if (!owner->HMAC.l[0]) // If no owner data,
+ SetupOwnerOpt(m, intf, &opt.resrec.rdata->u.opt[1]); // use our own interface information
+ else // otherwise, use the owner data we were given
+ {
+ opt.resrec.rdata->u.opt[1].u.owner = *owner;
+ opt.resrec.rdata->u.opt[1].opt = kDNSOpt_Owner;
+ opt.resrec.rdata->u.opt[1].optlen = DNSOpt_Owner_Space(&owner->HMAC, &owner->IMAC) - 4;
+ }
+ LogSPS("SendSPSRegistration put %s %s", intf->ifname, ARDisplayString(m, &opt));
+ p = PutResourceRecordTTLWithLimit(&m->omsg, p, &m->omsg.h.numAdditionals, &opt.resrec, opt.resrec.rroriginalttl, m->omsg.data + AbsoluteMaxDNSMessageData);
+ if (!p)
+ LogMsg("SendSPSRegistration: Failed to put OPT record (%d updates) %s", m->omsg.h.mDNS_numUpdates, ARDisplayString(m, &opt));
+ else
+ {
+ mStatus err;
+
+ LogSPS("SendSPSRegistration: Sending Update %s %d (%d) id %5d with %d records %d bytes to %#a:%d", intf->ifname, intf->NextSPSAttempt, sps,
+ mDNSVal16(m->omsg.h.id), m->omsg.h.mDNS_numUpdates, p - m->omsg.data, &intf->SPSAddr[sps], mDNSVal16(intf->SPSPort[sps]));
+ // if (intf->NextSPSAttempt < 5) m->omsg.h.flags = zeroID; // For simulating packet loss
+ err = mDNSSendDNSMessage(m, &m->omsg, p, intf->InterfaceID, mDNSNULL, &intf->SPSAddr[sps], intf->SPSPort[sps], mDNSNULL, mDNSNULL, mDNSfalse);
+ if (err) LogSPS("SendSPSRegistration: mDNSSendDNSMessage err %d", err);
+ if (err && intf->SPSAddr[sps].type == mDNSAddrType_IPv4 && intf->NetWakeResolve[sps].ThisQInterval == -1)
+ {
+ LogSPS("SendSPSRegistration %d %##s failed to send to IPv4 address; will try IPv6 instead", sps, intf->NetWakeResolve[sps].qname.c);
+ intf->NetWakeResolve[sps].qtype = kDNSType_AAAA;
+ mDNS_StartQuery_internal(m, &intf->NetWakeResolve[sps]);
+ return;
+ }
+ }
+ }
+ }
+
+ intf->NextSPSAttemptTime = m->timenow + mDNSPlatformOneSecond * 10; // If successful, update NextSPSAttemptTime
exit:
- if (mDNSOpaque16IsZero(id) && intf->NextSPSAttempt < 8) intf->NextSPSAttempt++;
- }
+ if (mDNSOpaque16IsZero(id) && intf->NextSPSAttempt < 8) intf->NextSPSAttempt++;
+}
mDNSlocal mDNSBool RecordIsFirstOccurrenceOfOwner(mDNS *const m, const AuthRecord *const rr)
- {
- AuthRecord *ar;
- for (ar = m->ResourceRecords; ar && ar != rr; ar=ar->next)
- if (mDNSPlatformMemSame(&rr->WakeUp, &ar->WakeUp, sizeof(rr->WakeUp))) return mDNSfalse;
- return mDNStrue;
- }
+{
+ AuthRecord *ar;
+ for (ar = m->ResourceRecords; ar && ar != rr; ar=ar->next)
+ if (mDNSPlatformMemSame(&rr->WakeUp, &ar->WakeUp, sizeof(rr->WakeUp))) return mDNSfalse;
+ return mDNStrue;
+}
+
+mDNSlocal void mDNSCoreStoreProxyRR(mDNS *const m, const mDNSInterfaceID InterfaceID, AuthRecord *const rr)
+{
+ AuthRecord *newRR = mDNSPlatformMemAllocate(sizeof(AuthRecord));
+
+ if (newRR == mDNSNULL)
+ {
+ LogSPS("%s : could not allocate memory for new resource record", __func__);
+ return;
+ }
+
+ mDNSPlatformMemZero(newRR, sizeof(AuthRecord));
+ mDNS_SetupResourceRecord(newRR, mDNSNULL, InterfaceID, rr->resrec.rrtype,
+ rr->resrec.rroriginalttl, rr->resrec.RecordType,
+ rr->ARType, mDNSNULL, mDNSNULL);
+
+ AssignDomainName(&newRR->namestorage, &rr->namestorage);
+ newRR->resrec.rdlength = DomainNameLength(rr->resrec.name);
+ newRR->resrec.namehash = DomainNameHashValue(newRR->resrec.name);
+ newRR->resrec.rrclass = rr->resrec.rrclass;
+
+ if (rr->resrec.rrtype == kDNSType_A)
+ {
+ newRR->resrec.rdata->u.ipv4 = rr->resrec.rdata->u.ipv4;
+ }
+ else if (rr->resrec.rrtype == kDNSType_AAAA)
+ {
+ newRR->resrec.rdata->u.ipv6 = rr->resrec.rdata->u.ipv6;
+ }
+ SetNewRData(&newRR->resrec, mDNSNULL, 0);
+
+ // Insert the new node at the head of the list.
+ newRR->next = m->SPSRRSet;
+ m->SPSRRSet = newRR;
+ LogSPS("%s : Storing proxy record : %s ", __func__, ARDisplayString(m, rr));
+}
+
+// Some records are interface specific and some are not. The ones that are supposed to be registered
+// on multiple interfaces need to be initialized with all the valid interfaces on which it will be sent.
+// updateIntID bit field tells us on which interfaces we need to register this record. When we get an
+// ack from the sleep proxy server, we clear the interface bit. This way, we know when a record completes
+// registration on all the interfaces
+mDNSlocal void SPSInitRecordsBeforeUpdate(mDNS *const m, mDNSOpaque64 updateIntID, mDNSBool *WakeOnlyService)
+{
+ AuthRecord *ar;
+ LogSPS("SPSInitRecordsBeforeUpdate: UpdateIntID 0x%x 0x%x", updateIntID.l[1], updateIntID.l[0]);
+
+ *WakeOnlyService = mDNSfalse;
+
+ // Before we store the A and AAAA records that we are going to register with the sleep proxy,
+ // make sure that the old sleep proxy records are removed.
+ mDNSCoreFreeProxyRR(m);
+
+ // For records that are registered only on a specific interface, mark only that bit as it will
+ // never be registered on any other interface. For others, it should be sent on all interfaces.
+ for (ar = m->ResourceRecords; ar; ar=ar->next)
+ {
+ ar->updateIntID = zeroOpaque64;
+ ar->updateid = zeroID;
+ if (AuthRecord_uDNS(ar))
+ {
+ continue;
+ }
+ if (ar->AuthFlags & AuthFlagsWakeOnly)
+ {
+ if (ar->resrec.RecordType == kDNSRecordTypeShared && ar->RequireGoodbye)
+ {
+ ar->ImmedAnswer = mDNSInterfaceMark;
+ *WakeOnlyService = mDNStrue;
+ continue;
+ }
+ }
+ if (!ar->resrec.InterfaceID)
+ {
+ LogSPS("Setting scopeid (ALL) 0x%x 0x%x for %s", updateIntID.l[1], updateIntID.l[0], ARDisplayString(m, ar));
+ ar->updateIntID = updateIntID;
+ }
+ else
+ {
+ // Filter records that belong to interfaces that we won't register the records on. UpdateIntID captures
+ // exactly this.
+ mDNSu32 scopeid = mDNSPlatformInterfaceIndexfromInterfaceID(m, ar->resrec.InterfaceID, mDNStrue);
+ if ((scopeid < (sizeof(updateIntID) * mDNSNBBY)) && bit_get_opaque64(updateIntID, scopeid))
+ {
+ bit_set_opaque64(ar->updateIntID, scopeid);
+ LogSPS("SPSInitRecordsBeforeUpdate: Setting scopeid(%d) 0x%x 0x%x for %s", scopeid, ar->updateIntID.l[1],
+ ar->updateIntID.l[0], ARDisplayString(m, ar));
+ }
+ else
+ {
+ LogSPS("SPSInitRecordsBeforeUpdate: scopeid %d beyond range or not valid for SPS registration", scopeid);
+ }
+ }
+ // Store the A and AAAA records that we registered with the sleep proxy.
+ // We will use this to prevent spurious name conflicts that may occur when we wake up
+ if (ar->resrec.rrtype == kDNSType_A || ar->resrec.rrtype == kDNSType_AAAA)
+ {
+ mDNSCoreStoreProxyRR(m, ar->resrec.InterfaceID, ar);
+ }
+ }
+}
mDNSlocal void SendSPSRegistration(mDNS *const m, NetworkInterfaceInfo *const intf, const mDNSOpaque16 id)
- {
- AuthRecord *ar;
- OwnerOptData owner = zeroOwner;
-
- SendSPSRegistrationForOwner(m, intf, id, &owner);
-
- for (ar = m->ResourceRecords; ar; ar=ar->next)
- {
- if (!mDNSPlatformMemSame(&owner, &ar->WakeUp, sizeof(owner)) && RecordIsFirstOccurrenceOfOwner(m, ar))
- {
- owner = ar->WakeUp;
- SendSPSRegistrationForOwner(m, intf, id, &owner);
- }
- }
- }
+{
+ AuthRecord *ar;
+ OwnerOptData owner = zeroOwner;
+
+ SendSPSRegistrationForOwner(m, intf, id, &owner);
+
+ for (ar = m->ResourceRecords; ar; ar=ar->next)
+ {
+ if (!mDNSPlatformMemSame(&owner, &ar->WakeUp, sizeof(owner)) && RecordIsFirstOccurrenceOfOwner(m, ar))
+ {
+ owner = ar->WakeUp;
+ SendSPSRegistrationForOwner(m, intf, id, &owner);
+ }
+ }
+}
// RetrySPSRegistrations is called from SendResponses, with the lock held
mDNSlocal void RetrySPSRegistrations(mDNS *const m)
- {
- AuthRecord *rr;
- NetworkInterfaceInfo *intf;
-
- // First make sure none of our interfaces' NextSPSAttemptTimes are inadvertently set to m->timenow + mDNSPlatformOneSecond * 10
- for (intf = GetFirstActiveInterface(m->HostInterfaces); intf; intf = GetFirstActiveInterface(intf->next))
- if (intf->NextSPSAttempt && intf->NextSPSAttemptTime == m->timenow + mDNSPlatformOneSecond * 10)
- intf->NextSPSAttemptTime++;
-
- // Retry any record registrations that are due
- for (rr = m->ResourceRecords; rr; rr=rr->next)
- if (!AuthRecord_uDNS(rr) && !mDNSOpaque16IsZero(rr->updateid) && m->timenow - (rr->LastAPTime + rr->ThisAPInterval) >= 0)
- for (intf = GetFirstActiveInterface(m->HostInterfaces); intf; intf = GetFirstActiveInterface(intf->next))
- if (!rr->resrec.InterfaceID || rr->resrec.InterfaceID == intf->InterfaceID)
- {
- LogSPS("RetrySPSRegistrations: %s", ARDisplayString(m, rr));
- SendSPSRegistration(m, intf, rr->updateid);
- }
-
- // For interfaces where we did an SPS registration attempt, increment intf->NextSPSAttempt
- for (intf = GetFirstActiveInterface(m->HostInterfaces); intf; intf = GetFirstActiveInterface(intf->next))
- if (intf->NextSPSAttempt && intf->NextSPSAttemptTime == m->timenow + mDNSPlatformOneSecond * 10 && intf->NextSPSAttempt < 8)
- intf->NextSPSAttempt++;
- }
+{
+ AuthRecord *rr;
+ NetworkInterfaceInfo *intf;
+
+ // First make sure none of our interfaces' NextSPSAttemptTimes are inadvertently set to m->timenow + mDNSPlatformOneSecond * 10
+ for (intf = GetFirstActiveInterface(m->HostInterfaces); intf; intf = GetFirstActiveInterface(intf->next))
+ if (intf->NextSPSAttempt && intf->NextSPSAttemptTime == m->timenow + mDNSPlatformOneSecond * 10)
+ intf->NextSPSAttemptTime++;
+
+ // Retry any record registrations that are due
+ for (rr = m->ResourceRecords; rr; rr=rr->next)
+ if (!AuthRecord_uDNS(rr) && !mDNSOpaque16IsZero(rr->updateid) && m->timenow - (rr->LastAPTime + rr->ThisAPInterval) >= 0)
+ {
+ for (intf = GetFirstActiveInterface(m->HostInterfaces); intf; intf = GetFirstActiveInterface(intf->next))
+ {
+ // If we still have registrations pending on this interface, send it now
+ mDNSu32 scopeid = mDNSPlatformInterfaceIndexfromInterfaceID(m, intf->InterfaceID, mDNStrue);
+ if ((scopeid >= (sizeof(rr->updateIntID) * mDNSNBBY) || bit_get_opaque64(rr->updateIntID, scopeid)) &&
+ (!rr->resrec.InterfaceID || rr->resrec.InterfaceID == intf->InterfaceID))
+ {
+ LogSPS("RetrySPSRegistrations: 0x%x 0x%x (updateid %d) %s", rr->updateIntID.l[1], rr->updateIntID.l[0], mDNSVal16(rr->updateid), ARDisplayString(m, rr));
+ SendSPSRegistration(m, intf, rr->updateid);
+ }
+ }
+ }
+
+ // For interfaces where we did an SPS registration attempt, increment intf->NextSPSAttempt
+ for (intf = GetFirstActiveInterface(m->HostInterfaces); intf; intf = GetFirstActiveInterface(intf->next))
+ if (intf->NextSPSAttempt && intf->NextSPSAttemptTime == m->timenow + mDNSPlatformOneSecond * 10 && intf->NextSPSAttempt < 8)
+ intf->NextSPSAttempt++;
+}
mDNSlocal void NetWakeResolve(mDNS *const m, DNSQuestion *question, const ResourceRecord *const answer, QC_result AddRecord)
- {
- NetworkInterfaceInfo *intf = (NetworkInterfaceInfo *)question->QuestionContext;
- int sps = (int)(question - intf->NetWakeResolve);
- (void)m; // Unused
- LogSPS("NetWakeResolve: SPS: %d Add: %d %s", sps, AddRecord, RRDisplayString(m, answer));
-
- if (!AddRecord) return; // Don't care about REMOVE events
- if (answer->rrtype != question->qtype) return; // Don't care about CNAMEs
-
- // if (answer->rrtype == kDNSType_AAAA && sps == 0) return; // To test failing to resolve sleep proxy's address
-
- if (answer->rrtype == kDNSType_SRV)
- {
- // 1. Got the SRV record; now look up the target host's IPv6 link-local address
- mDNS_StopQuery(m, question);
- intf->SPSPort[sps] = answer->rdata->u.srv.port;
- AssignDomainName(&question->qname, &answer->rdata->u.srv.target);
- question->qtype = kDNSType_AAAA;
- mDNS_StartQuery(m, question);
- }
- else if (answer->rrtype == kDNSType_AAAA && answer->rdlength == sizeof(mDNSv6Addr) && mDNSv6AddressIsLinkLocal(&answer->rdata->u.ipv6))
- {
- // 2. Got the target host's IPv6 link-local address; record address and initiate an SPS registration if appropriate
- mDNS_StopQuery(m, question);
- question->ThisQInterval = -1;
- intf->SPSAddr[sps].type = mDNSAddrType_IPv6;
- intf->SPSAddr[sps].ip.v6 = answer->rdata->u.ipv6;
- mDNS_Lock(m);
- if (sps == intf->NextSPSAttempt/3) SendSPSRegistration(m, intf, zeroID); // If we're ready for this result, use it now
- mDNS_Unlock(m);
- }
- else if (answer->rrtype == kDNSType_AAAA && answer->rdlength == 0)
- {
- // 3. Got negative response -- target host apparently has IPv6 disabled -- so try looking up the target host's IPv4 address(es) instead
- mDNS_StopQuery(m, question);
- LogSPS("NetWakeResolve: SPS %d %##s has no IPv6 address, will try IPv4 instead", sps, question->qname.c);
- question->qtype = kDNSType_A;
- mDNS_StartQuery(m, question);
- }
- else if (answer->rrtype == kDNSType_A && answer->rdlength == sizeof(mDNSv4Addr))
- {
- // 4. Got an IPv4 address for the target host; record address and initiate an SPS registration if appropriate
- mDNS_StopQuery(m, question);
- question->ThisQInterval = -1;
- intf->SPSAddr[sps].type = mDNSAddrType_IPv4;
- intf->SPSAddr[sps].ip.v4 = answer->rdata->u.ipv4;
- mDNS_Lock(m);
- if (sps == intf->NextSPSAttempt/3) SendSPSRegistration(m, intf, zeroID); // If we're ready for this result, use it now
- mDNS_Unlock(m);
- }
- }
+{
+ NetworkInterfaceInfo *intf = (NetworkInterfaceInfo *)question->QuestionContext;
+ int sps = (int)(question - intf->NetWakeResolve);
+ (void)m; // Unused
+ LogSPS("NetWakeResolve: SPS: %d Add: %d %s", sps, AddRecord, RRDisplayString(m, answer));
-mDNSexport mDNSBool mDNSCoreHaveAdvertisedMulticastServices(mDNS *const m)
- {
- AuthRecord *rr;
- for (rr = m->ResourceRecords; rr; rr=rr->next)
- if (rr->resrec.rrtype == kDNSType_SRV && !AuthRecord_uDNS(rr) && !mDNSSameIPPort(rr->resrec.rdata->u.srv.port, DiscardPort))
- return mDNStrue;
- return mDNSfalse;
- }
-
-mDNSlocal void SendSleepGoodbyes(mDNS *const m)
- {
- AuthRecord *rr;
- m->SleepState = SleepState_Sleeping;
+ if (!AddRecord) return; // Don't care about REMOVE events
+ if (answer->rrtype != question->qtype) return; // Don't care about CNAMEs
+
+ // if (answer->rrtype == kDNSType_AAAA && sps == 0) return; // To test failing to resolve sleep proxy's address
+
+ if (answer->rrtype == kDNSType_SRV)
+ {
+ // 1. Got the SRV record; now look up the target host's IP address
+ mDNS_StopQuery(m, question);
+ intf->SPSPort[sps] = answer->rdata->u.srv.port;
+ AssignDomainName(&question->qname, &answer->rdata->u.srv.target);
+ question->qtype = kDNSType_A;
+ mDNS_StartQuery(m, question);
+ }
+ else if (answer->rrtype == kDNSType_A && answer->rdlength == sizeof(mDNSv4Addr))
+ {
+ // 2. Got an IPv4 address for the target host; record address and initiate an SPS registration if appropriate
+ mDNS_StopQuery(m, question);
+ question->ThisQInterval = -1;
+ intf->SPSAddr[sps].type = mDNSAddrType_IPv4;
+ intf->SPSAddr[sps].ip.v4 = answer->rdata->u.ipv4;
+ mDNS_Lock(m);
+ if (sps == intf->NextSPSAttempt/3) SendSPSRegistration(m, intf, zeroID); // If we're ready for this result, use it now
+ mDNS_Unlock(m);
+ }
+ else if (answer->rrtype == kDNSType_A && answer->rdlength == 0)
+ {
+ // 3. Got negative response -- target host apparently has IPv6 disabled -- so try looking up the target host's IPv4 address(es) instead
+ mDNS_StopQuery(m, question);
+ LogSPS("NetWakeResolve: SPS %d %##s has no IPv4 address, will try IPv6 instead", sps, question->qname.c);
+ question->qtype = kDNSType_AAAA;
+ mDNS_StartQuery(m, question);
+ }
+ else if (answer->rrtype == kDNSType_AAAA && answer->rdlength == sizeof(mDNSv6Addr) && mDNSv6AddressIsLinkLocal(&answer->rdata->u.ipv6))
+ {
+ // 4. Got the target host's IPv6 link-local address; record address and initiate an SPS registration if appropriate
+ mDNS_StopQuery(m, question);
+ question->ThisQInterval = -1;
+ intf->SPSAddr[sps].type = mDNSAddrType_IPv6;
+ intf->SPSAddr[sps].ip.v6 = answer->rdata->u.ipv6;
+ mDNS_Lock(m);
+ if (sps == intf->NextSPSAttempt/3) SendSPSRegistration(m, intf, zeroID); // If we're ready for this result, use it now
+ mDNS_Unlock(m);
+ }
+}
+mDNSexport mDNSBool mDNSCoreHaveAdvertisedMulticastServices(mDNS *const m)
+{
+ AuthRecord *rr;
+ for (rr = m->ResourceRecords; rr; rr=rr->next)
+ if (mDNS_KeepaliveRecord(&rr->resrec) || (rr->resrec.rrtype == kDNSType_SRV && !AuthRecord_uDNS(rr) && !mDNSSameIPPort(rr->resrec.rdata->u.srv.port, DiscardPort)))
+ return mDNStrue;
+ return mDNSfalse;
+}
+
+#ifdef APPLE_OSX_mDNSResponder
+// This function is used only in the case of local NIC proxy. For external
+// sleep proxy server, we do this in SPSInitRecordsBeforeUpdate when we
+// walk the resource records.
+mDNSlocal void SendGoodbyesForWakeOnlyService(mDNS *const m, mDNSBool *WakeOnlyService)
+{
+ AuthRecord *rr;
+
+ *WakeOnlyService = mDNSfalse;
+
+ // Mark all the records we need to deregister and send them
+ for (rr = m->ResourceRecords; rr; rr=rr->next)
+ {
+ if ((rr->AuthFlags & AuthFlagsWakeOnly) &&
+ rr->resrec.RecordType == kDNSRecordTypeShared && rr->RequireGoodbye)
+ {
+ rr->ImmedAnswer = mDNSInterfaceMark;
+ *WakeOnlyService = mDNStrue;
+ }
+ }
+}
+#endif // APPLE_OSx_mDNSResponder
+
+mDNSlocal void SendSleepGoodbyes(mDNS *const m, mDNSBool AllInterfaces, mDNSBool unicast)
+{
+ AuthRecord *rr;
+ m->SleepState = SleepState_Sleeping;
+
+ // If AllInterfaces is not set, the caller has already marked it appropriately
+ // on which interfaces this should be sent.
+ if (AllInterfaces)
+ {
+ NetworkInterfaceInfo *intf;
+ for (intf = GetFirstActiveInterface(m->HostInterfaces); intf; intf = GetFirstActiveInterface(intf->next))
+ {
+ intf->SendGoodbyes = 1;
+ }
+ }
+ if (unicast)
+ {
#ifndef UNICAST_DISABLED
- SleepRecordRegistrations(m); // If we have no SPS, need to deregister our uDNS records
+ SleepRecordRegistrations(m); // If we have no SPS, need to deregister our uDNS records
#endif /* UNICAST_DISABLED */
+ }
+
+ // Mark all the records we need to deregister and send them
+ for (rr = m->ResourceRecords; rr; rr=rr->next)
+ if (rr->resrec.RecordType == kDNSRecordTypeShared && rr->RequireGoodbye)
+ rr->ImmedAnswer = mDNSInterfaceMark;
+ SendResponses(m);
+}
+
+/*
+ * This function attempts to detect if multiple interfaces are on the same subnet.
+ * It makes this determination based only on the IPv4 Addresses and subnet masks.
+ * IPv6 link local addresses that are configured by default on all interfaces make
+ * it hard to make this determination
+ *
+ * The 'real' fix for this would be to send out multicast packets over one interface
+ * and conclude that multiple interfaces are on the same subnet only if these packets
+ * are seen on other interfaces on the same system
+ */
+mDNSlocal mDNSBool skipSameSubnetRegistration(mDNS *const m, mDNSInterfaceID *regID, mDNSu32 count, mDNSInterfaceID intfid)
+{
+ NetworkInterfaceInfo *intf;
+ NetworkInterfaceInfo *newIntf;
+ mDNSu32 i;
- // Mark all the records we need to deregister and send them
- for (rr = m->ResourceRecords; rr; rr=rr->next)
- if (rr->resrec.RecordType == kDNSRecordTypeShared && rr->RequireGoodbye)
- rr->ImmedAnswer = mDNSInterfaceMark;
- SendResponses(m);
- }
+ for (newIntf = FirstInterfaceForID(m, intfid); newIntf; newIntf = newIntf->next)
+ {
+ if ((newIntf->InterfaceID != intfid) ||
+ (newIntf->ip.type != mDNSAddrType_IPv4))
+ {
+ continue;
+ }
+ for ( i = 0; i < count; i++)
+ {
+ for (intf = FirstInterfaceForID(m, regID[i]); intf; intf = intf->next)
+ {
+ if ((intf->InterfaceID != regID[i]) ||
+ (intf->ip.type != mDNSAddrType_IPv4))
+ {
+ continue;
+ }
+ if ((intf->ip.ip.v4.NotAnInteger & intf->mask.ip.v4.NotAnInteger) == (newIntf->ip.ip.v4.NotAnInteger & newIntf->mask.ip.v4.NotAnInteger))
+ {
+ LogSPS("%s : Already registered for the same subnet (IPv4) for interface %s", __func__, intf->ifname);
+ return (mDNStrue);
+ }
+ }
+ }
+ }
+ return (mDNSfalse);
+}
+
+mDNSlocal void DoKeepaliveCallbacks(mDNS *m)
+{
+ // Loop through the keepalive records and callback with an error
+ m->CurrentRecord = m->ResourceRecords;
+ while (m->CurrentRecord)
+ {
+ AuthRecord *const rr = m->CurrentRecord;
+ if ((mDNS_KeepaliveRecord(&rr->resrec)) && (rr->resrec.RecordType != kDNSRecordTypeDeregistering))
+ {
+ LogSPS("DoKeepaliveCallbacks: Invoking the callback for %s", ARDisplayString(m, rr));
+ if (rr->RecordCallback)
+ rr->RecordCallback(m, rr, mStatus_BadStateErr);
+ }
+ if (m->CurrentRecord == rr) // If m->CurrentRecord was not advanced for us, do it now
+ m->CurrentRecord = rr->next;
+ }
+}
// BeginSleepProcessing is called, with the lock held, from either mDNS_Execute or mDNSCoreMachineSleep
mDNSlocal void BeginSleepProcessing(mDNS *const m)
- {
- mDNSBool SendGoodbyes = mDNStrue;
- const CacheRecord *sps[3] = { mDNSNULL };
-
- m->NextScheduledSPRetry = m->timenow;
-
- if (!m->SystemWakeOnLANEnabled) LogSPS("BeginSleepProcessing: m->SystemWakeOnLANEnabled is false");
- else if (!mDNSCoreHaveAdvertisedMulticastServices(m)) LogSPS("BeginSleepProcessing: No advertised services");
- else // If we have at least one advertised service
- {
- NetworkInterfaceInfo *intf;
- for (intf = GetFirstActiveInterface(m->HostInterfaces); intf; intf = GetFirstActiveInterface(intf->next))
- {
- if (!intf->NetWake) LogSPS("BeginSleepProcessing: %-6s not capable of magic packet wakeup", intf->ifname);
+{
+ mDNSBool SendGoodbyes = mDNStrue;
+ mDNSBool WakeOnlyService = mDNSfalse;
+ mDNSBool invokeKACallback = mDNStrue;
+ const CacheRecord *sps[3] = { mDNSNULL };
+ mDNSOpaque64 updateIntID = zeroOpaque64;
+ mDNSInterfaceID registeredIntfIDS[128];
+ mDNSu32 registeredCount = 0;
+ int skippedRegistrations = 0;
+
+ m->NextScheduledSPRetry = m->timenow;
+
+ if (!m->SystemWakeOnLANEnabled) LogSPS("BeginSleepProcessing: m->SystemWakeOnLANEnabled is false");
+ else if (!mDNSCoreHaveAdvertisedMulticastServices(m)) LogSPS("BeginSleepProcessing: No advertised services");
+ else // If we have at least one advertised service
+ {
+ NetworkInterfaceInfo *intf;
+
+ // Clear out the SCDynamic entry that stores the external SPS information
+ mDNSPlatformClearSPSMACAddr();
+
+ for (intf = GetFirstActiveInterface(m->HostInterfaces); intf; intf = GetFirstActiveInterface(intf->next))
+ {
+ // Intialize it to false. These values make sense only when SleepState is set to Sleeping.
+ intf->SendGoodbyes = 0;
+
+ // If it is not multicast capable, we could not have possibly discovered sleep proxy
+ // servers.
+ if (!intf->McastTxRx || mDNSPlatformInterfaceIsD2D(intf->InterfaceID))
+ {
+ LogSPS("BeginSleepProcessing: %-6s Ignoring for registrations", intf->ifname);
+ continue;
+ }
+
+ // If we are not capable of WOMP, then don't register with sleep proxy.
+ //
+ // Note: If we are not NetWake capable, we don't browse for the sleep proxy server.
+ // We might find sleep proxy servers in the cache and start a resolve on them.
+ // But then if the interface goes away, we won't stop these questions because
+ // mDNS_DeactivateNetWake_internal assumes that a browse has been started for it
+ // to stop both the browse and resolve questions.
+ if (!intf->NetWake)
+ {
+ LogSPS("BeginSleepProcessing: %-6s not capable of magic packet wakeup", intf->ifname);
+ intf->SendGoodbyes = 1;
+ skippedRegistrations++;
+ continue;
+ }
+
+ // Check if we have already registered with a sleep proxy for this subnet
+ if (skipSameSubnetRegistration(m, registeredIntfIDS, registeredCount, intf->InterfaceID))
+ {
+ LogSPS("%s : Skipping sleep proxy registration on %s", __func__, intf->ifname);
+ continue;
+ }
+
+#if APPLE_OSX_mDNSResponder
+ else if (SupportsInNICProxy(intf))
+ {
+ if (ActivateLocalProxy(m, intf) == mStatus_NoError)
+ {
+ SendGoodbyesForWakeOnlyService(m, &WakeOnlyService);
+ SendGoodbyes = mDNSfalse;
+ invokeKACallback = mDNSfalse;
+ LogSPS("BeginSleepProcessing: %-6s using local proxy", intf->ifname);
+ // This will leave m->SleepState set to SleepState_Transferring,
+ // which is okay because with no outstanding resolves, or updates in flight,
+ // mDNSCoreReadyForSleep() will conclude correctly that all the updates have already completed
+
+ registeredIntfIDS[registeredCount] = intf->InterfaceID;
+ registeredCount++;
+ }
+ }
+#endif // APPLE_OSX_mDNSResponder
+ else
+ {
#if APPLE_OSX_mDNSResponder
- else if (ActivateLocalProxy(m, intf->ifname) == mStatus_NoError)
- {
- SendGoodbyes = mDNSfalse;
- LogSPS("BeginSleepProcessing: %-6s using local proxy", intf->ifname);
- // This will leave m->SleepState set to SleepState_Transferring,
- // which is okay because with no outstanding resolves, or updates in flight,
- // mDNSCoreReadyForSleep() will conclude correctly that all the updates have already completed
- }
+ // If on battery, do not attempt to offload to external sleep proxies
+ if (m->SystemWakeOnLANEnabled == mDNS_WakeOnBattery)
+ {
+ LogSPS("BegingSleepProcessing: Not connected to AC power - Not registering with an external sleep proxy.");
+ return;
+ }
#endif // APPLE_OSX_mDNSResponder
- else
- {
- FindSPSInCache(m, &intf->NetWakeBrowse, sps);
- if (!sps[0]) LogSPS("BeginSleepProcessing: %-6s %#a No Sleep Proxy Server found (Next Browse Q in %d, interval %d)",
- intf->ifname, &intf->ip, NextQSendTime(&intf->NetWakeBrowse) - m->timenow, intf->NetWakeBrowse.ThisQInterval);
- else
- {
- int i;
- SendGoodbyes = mDNSfalse;
- intf->NextSPSAttempt = 0;
- intf->NextSPSAttemptTime = m->timenow + mDNSPlatformOneSecond;
- // Don't need to set m->NextScheduledSPRetry here because we already set "m->NextScheduledSPRetry = m->timenow" above
- for (i=0; i<3; i++)
- {
+ FindSPSInCache(m, &intf->NetWakeBrowse, sps);
+ if (!sps[0]) LogSPS("BeginSleepProcessing: %-6s %#a No Sleep Proxy Server found (Next Browse Q in %d, interval %d)",
+ intf->ifname, &intf->ip, NextQSendTime(&intf->NetWakeBrowse) - m->timenow, intf->NetWakeBrowse.ThisQInterval);
+ else
+ {
+ int i;
+ mDNSu32 scopeid;
+ SendGoodbyes = mDNSfalse;
+ intf->NextSPSAttempt = 0;
+ intf->NextSPSAttemptTime = m->timenow + mDNSPlatformOneSecond;
+
+ scopeid = mDNSPlatformInterfaceIndexfromInterfaceID(m, intf->InterfaceID, mDNStrue);
+ // Now we know for sure that we have to wait for registration to complete on this interface.
+ if (scopeid < (sizeof(updateIntID) * mDNSNBBY))
+ bit_set_opaque64(updateIntID, scopeid);
+
+ // Don't need to set m->NextScheduledSPRetry here because we already set "m->NextScheduledSPRetry = m->timenow" above
+ for (i=0; i<3; i++)
+ {
#if ForceAlerts
- if (intf->SPSAddr[i].type)
- { LogMsg("BeginSleepProcessing: %s %d intf->SPSAddr[i].type %d", intf->ifname, i, intf->SPSAddr[i].type); *(long*)0 = 0; }
- if (intf->NetWakeResolve[i].ThisQInterval >= 0)
- { LogMsg("BeginSleepProcessing: %s %d intf->NetWakeResolve[i].ThisQInterval %d", intf->ifname, i, intf->NetWakeResolve[i].ThisQInterval); *(long*)0 = 0; }
+ if (intf->SPSAddr[i].type)
+ { LogMsg("BeginSleepProcessing: %s %d intf->SPSAddr[i].type %d", intf->ifname, i, intf->SPSAddr[i].type); *(long*)0 = 0; }
+ if (intf->NetWakeResolve[i].ThisQInterval >= 0)
+ { LogMsg("BeginSleepProcessing: %s %d intf->NetWakeResolve[i].ThisQInterval %d", intf->ifname, i, intf->NetWakeResolve[i].ThisQInterval); *(long*)0 = 0; }
#endif
- intf->SPSAddr[i].type = mDNSAddrType_None;
- if (intf->NetWakeResolve[i].ThisQInterval >= 0) mDNS_StopQuery(m, &intf->NetWakeResolve[i]);
- intf->NetWakeResolve[i].ThisQInterval = -1;
- if (sps[i])
- {
- LogSPS("BeginSleepProcessing: %-6s Found Sleep Proxy Server %d TTL %d %s", intf->ifname, i, sps[i]->resrec.rroriginalttl, CRDisplayString(m, sps[i]));
- mDNS_SetupQuestion(&intf->NetWakeResolve[i], intf->InterfaceID, &sps[i]->resrec.rdata->u.name, kDNSType_SRV, NetWakeResolve, intf);
- intf->NetWakeResolve[i].ReturnIntermed = mDNStrue;
- mDNS_StartQuery_internal(m, &intf->NetWakeResolve[i]);
- }
- }
- }
- }
- }
- }
-
- if (SendGoodbyes) // If we didn't find even one Sleep Proxy
- {
- LogSPS("BeginSleepProcessing: Not registering with Sleep Proxy Server");
- SendSleepGoodbyes(m);
- }
- }
+ intf->SPSAddr[i].type = mDNSAddrType_None;
+ if (intf->NetWakeResolve[i].ThisQInterval >= 0) mDNS_StopQuery(m, &intf->NetWakeResolve[i]);
+ intf->NetWakeResolve[i].ThisQInterval = -1;
+ if (sps[i])
+ {
+ LogSPS("BeginSleepProcessing: %-6s Found Sleep Proxy Server %d TTL %d %s", intf->ifname, i, sps[i]->resrec.rroriginalttl, CRDisplayString(m, sps[i]));
+ mDNS_SetupQuestion(&intf->NetWakeResolve[i], intf->InterfaceID, &sps[i]->resrec.rdata->u.name, kDNSType_SRV, NetWakeResolve, intf);
+ intf->NetWakeResolve[i].ReturnIntermed = mDNStrue;
+ mDNS_StartQuery_internal(m, &intf->NetWakeResolve[i]);
+
+ // If we are registering with a Sleep Proxy for a new subnet, add it to our list
+ registeredIntfIDS[registeredCount] = intf->InterfaceID;
+ registeredCount++;
+ }
+ }
+ }
+ }
+ }
+ }
+
+ // If we have at least one interface on which we are registering with an external sleep proxy,
+ // initialize all the records appropriately.
+ if (!mDNSOpaque64IsZero(&updateIntID))
+ SPSInitRecordsBeforeUpdate(m, updateIntID, &WakeOnlyService);
+
+ // Call the applicaitons that registered a keepalive record to inform them that we failed to offload
+ // the records to a sleep proxy.
+ if (invokeKACallback)
+ {
+ LogSPS("BeginSleepProcessing: Did not register with an in-NIC proxy - invoking the callbacks for KA records");
+ DoKeepaliveCallbacks(m);
+ }
+
+ // SendSleepGoodbyes last two arguments control whether we send goodbyes on all
+ // interfaces and also deregister unicast registrations.
+ //
+ // - If there are no sleep proxy servers, then send goodbyes on all interfaces
+ // for both multicast and unicast.
+ //
+ // - If we skipped registrations on some interfaces, then we have already marked
+ // them appropriately above. We don't need to send goodbyes for unicast as
+ // we have registered with at least one sleep proxy.
+ //
+ // - If we are not planning to send any goodbyes, then check for WakeOnlyServices.
+ //
+ // Note: If we are planning to send goodbyes, we mark the record with mDNSInterfaceAny
+ // and call SendResponses which inturn calls ShouldSendGoodbyesBeforeSleep which looks
+ // at WakeOnlyServices first.
+ if (SendGoodbyes)
+ {
+ LogSPS("BeginSleepProcessing: Not registering with Sleep Proxy Server");
+ SendSleepGoodbyes(m, mDNStrue, mDNStrue);
+ }
+ else if (skippedRegistrations)
+ {
+ LogSPS("BeginSleepProcessing: Not registering with Sleep Proxy Server on all interfaces");
+ SendSleepGoodbyes(m, mDNSfalse, mDNSfalse);
+ }
+ else if (WakeOnlyService)
+ {
+ // If we saw WakeOnly service above, send the goodbyes now.
+ LogSPS("BeginSleepProcessing: Sending goodbyes for WakeOnlyServices");
+ SendResponses(m);
+ }
+}
// Call mDNSCoreMachineSleep(m, mDNStrue) when the machine is about to go to sleep.
// Call mDNSCoreMachineSleep(m, mDNSfalse) when the machine is has just woken up.
// Normally, the platform support layer below mDNSCore should call this, not the client layer above.
mDNSexport void mDNSCoreMachineSleep(mDNS *const m, mDNSBool sleep)
- {
- AuthRecord *rr;
-
- LogSPS("%s (old state %d) at %ld", sleep ? "Sleeping" : "Waking", m->SleepState, m->timenow);
-
- if (sleep && !m->SleepState) // Going to sleep
- {
- mDNS_Lock(m);
- // If we're going to sleep, need to stop advertising that we're a Sleep Proxy Server
- if (m->SPSSocket)
- {
- mDNSu8 oldstate = m->SPSState;
- mDNS_DropLockBeforeCallback(); // mDNS_DeregisterService expects to be called without the lock held, so we emulate that here
- m->SPSState = 2;
- if (oldstate == 1) mDNS_DeregisterService(m, &m->SPSRecords);
- mDNS_ReclaimLockAfterCallback();
- }
-
- m->SleepState = SleepState_Transferring;
- if (m->SystemWakeOnLANEnabled && m->DelaySleep)
- {
- // If we just woke up moments ago, allow ten seconds for networking to stabilize before going back to sleep
- LogSPS("mDNSCoreMachineSleep: Re-sleeping immediately after waking; will delay for %d ticks", m->DelaySleep - m->timenow);
- m->SleepLimit = NonZeroTime(m->DelaySleep + mDNSPlatformOneSecond * 10);
- }
- else
- {
- m->DelaySleep = 0;
- m->SleepLimit = NonZeroTime(m->timenow + mDNSPlatformOneSecond * 10);
- BeginSleepProcessing(m);
- }
+{
+ AuthRecord *rr;
+
+ LogSPS("%s (old state %d) at %ld", sleep ? "Sleeping" : "Waking", m->SleepState, m->timenow);
+
+ if (sleep && !m->SleepState) // Going to sleep
+ {
+ mDNS_Lock(m);
+ // If we're going to sleep, need to stop advertising that we're a Sleep Proxy Server
+ if (m->SPSSocket)
+ {
+ mDNSu8 oldstate = m->SPSState;
+ mDNS_DropLockBeforeCallback(); // mDNS_DeregisterService expects to be called without the lock held, so we emulate that here
+ m->SPSState = 2;
+#ifndef SPC_DISABLED
+ if (oldstate == 1) mDNS_DeregisterService(m, &m->SPSRecords);
+#else
+ (void)oldstate;
+#endif
+ mDNS_ReclaimLockAfterCallback();
+ }
+
+ m->SleepState = SleepState_Transferring;
+ if (m->SystemWakeOnLANEnabled && m->DelaySleep)
+ {
+ // If we just woke up moments ago, allow ten seconds for networking to stabilize before going back to sleep
+ LogSPS("mDNSCoreMachineSleep: Re-sleeping immediately after waking; will delay for %d ticks", m->DelaySleep - m->timenow);
+ m->SleepLimit = NonZeroTime(m->DelaySleep + mDNSPlatformOneSecond * 10);
+ }
+ else
+ {
+ m->DelaySleep = 0;
+ m->SleepLimit = NonZeroTime(m->timenow + mDNSPlatformOneSecond * 10);
+ m->mDNSStats.Sleeps++;
+ BeginSleepProcessing(m);
+ }
#ifndef UNICAST_DISABLED
- SuspendLLQs(m);
+ SuspendLLQs(m);
#endif
- mDNS_Unlock(m);
- // RemoveAutoTunnel6Record needs to be called outside the lock, as it grabs the lock also.
#if APPLE_OSX_mDNSResponder
- RemoveAutoTunnel6Record(m);
+ RemoveAutoTunnel6Record(m);
#endif
- LogSPS("mDNSCoreMachineSleep: m->SleepState %d (%s) seq %d", m->SleepState,
- m->SleepState == SleepState_Transferring ? "Transferring" :
- m->SleepState == SleepState_Sleeping ? "Sleeping" : "?", m->SleepSeqNum);
- }
- else if (!sleep) // Waking up
- {
- mDNSu32 slot;
- CacheGroup *cg;
- CacheRecord *cr;
- NetworkInterfaceInfo *intf;
-
- mDNS_Lock(m);
- // Reset SleepLimit back to 0 now that we're awake again.
- m->SleepLimit = 0;
-
- // If we were previously sleeping, but now we're not, increment m->SleepSeqNum to indicate that we're entering a new period of wakefulness
- if (m->SleepState != SleepState_Awake)
- {
- m->SleepState = SleepState_Awake;
- m->SleepSeqNum++;
- // If the machine wakes and then immediately tries to sleep again (e.g. a maintenance wake)
- // then we enforce a minimum delay of 16 seconds before we begin sleep processing.
- // This is to allow time for the Ethernet link to come up, DHCP to get an address, mDNS to issue queries, etc.,
- // before we make our determination of whether there's a Sleep Proxy out there we should register with.
- m->DelaySleep = NonZeroTime(m->timenow + mDNSPlatformOneSecond * 16);
- }
-
- if (m->SPSState == 3)
- {
- m->SPSState = 0;
- mDNSCoreBeSleepProxyServer_internal(m, m->SPSType, m->SPSPortability, m->SPSMarginalPower, m->SPSTotalPower);
- }
-
- // In case we gave up waiting and went to sleep before we got an ack from the Sleep Proxy,
- // on wake we go through our record list and clear updateid back to zero
- for (rr = m->ResourceRecords; rr; rr=rr->next) rr->updateid = zeroID;
-
- // ... and the same for NextSPSAttempt
- for (intf = GetFirstActiveInterface(m->HostInterfaces); intf; intf = GetFirstActiveInterface(intf->next)) intf->NextSPSAttempt = -1;
-
- // Restart unicast and multicast queries
- mDNSCoreRestartQueries(m);
-
- // and reactivtate service registrations
- m->NextSRVUpdate = NonZeroTime(m->timenow + mDNSPlatformOneSecond);
- LogInfo("mDNSCoreMachineSleep waking: NextSRVUpdate in %d %d", m->NextSRVUpdate - m->timenow, m->timenow);
-
- // 2. Re-validate our cache records
- FORALL_CACHERECORDS(slot, cg, cr)
- mDNS_Reconfirm_internal(m, cr, kDefaultReconfirmTimeForWake);
-
- // 3. Retrigger probing and announcing for all our authoritative records
- for (rr = m->ResourceRecords; rr; rr=rr->next)
- if (AuthRecord_uDNS(rr))
- {
- ActivateUnicastRegistration(m, rr);
- }
- else
- {
- if (rr->resrec.RecordType == kDNSRecordTypeVerified && !rr->DependentOn) rr->resrec.RecordType = kDNSRecordTypeUnique;
- rr->ProbeCount = DefaultProbeCountForRecordType(rr->resrec.RecordType);
- rr->AnnounceCount = InitialAnnounceCount;
- rr->SendNSECNow = mDNSNULL;
- InitializeLastAPTime(m, rr);
- }
-
- // 4. Refresh NAT mappings
- // We don't want to have to assume that all hardware can necessarily keep accurate
- // track of passage of time while asleep, so on wake we refresh our NAT mappings
- // We typically wake up with no interfaces active, so there's no need to rush to try to find our external address.
- // When we get a network configuration change, mDNSMacOSXNetworkChanged calls uDNS_SetupDNSConfig, which calls
- // mDNS_SetPrimaryInterfaceInfo, which then sets m->retryGetAddr to immediately request our external address from the NAT gateway.
- m->retryIntervalGetAddr = NATMAP_INIT_RETRY;
- m->retryGetAddr = m->timenow + mDNSPlatformOneSecond * 5;
- LogInfo("mDNSCoreMachineSleep: retryGetAddr in %d %d", m->retryGetAddr - m->timenow, m->timenow);
- RecreateNATMappings(m);
- mDNS_Unlock(m);
- }
- }
+ LogSPS("mDNSCoreMachineSleep: m->SleepState %d (%s) seq %d", m->SleepState,
+ m->SleepState == SleepState_Transferring ? "Transferring" :
+ m->SleepState == SleepState_Sleeping ? "Sleeping" : "?", m->SleepSeqNum);
+ mDNS_Unlock(m);
+ }
+ else if (!sleep) // Waking up
+ {
+ mDNSu32 slot;
+ CacheGroup *cg;
+ CacheRecord *cr;
+ NetworkInterfaceInfo *intf;
+ mDNSs32 currtime, diff;
+
+ mDNS_Lock(m);
+ // Reset SleepLimit back to 0 now that we're awake again.
+ m->SleepLimit = 0;
+
+ // If we were previously sleeping, but now we're not, increment m->SleepSeqNum to indicate that we're entering a new period of wakefulness
+ if (m->SleepState != SleepState_Awake)
+ {
+ m->SleepState = SleepState_Awake;
+ m->SleepSeqNum++;
+ // If the machine wakes and then immediately tries to sleep again (e.g. a maintenance wake)
+ // then we enforce a minimum delay of 16 seconds before we begin sleep processing.
+ // This is to allow time for the Ethernet link to come up, DHCP to get an address, mDNS to issue queries, etc.,
+ // before we make our determination of whether there's a Sleep Proxy out there we should register with.
+ m->DelaySleep = NonZeroTime(m->timenow + mDNSPlatformOneSecond * 16);
+ }
+
+ if (m->SPSState == 3)
+ {
+ m->SPSState = 0;
+ mDNSCoreBeSleepProxyServer_internal(m, m->SPSType, m->SPSPortability, m->SPSMarginalPower, m->SPSTotalPower, m->SPSFeatureFlags);
+ }
+ m->mDNSStats.Wakes++;
+
+ // ... and the same for NextSPSAttempt
+ for (intf = GetFirstActiveInterface(m->HostInterfaces); intf; intf = GetFirstActiveInterface(intf->next)) intf->NextSPSAttempt = -1;
+
+ // Restart unicast and multicast queries
+ mDNSCoreRestartQueries(m);
+
+ // and reactivtate service registrations
+ m->NextSRVUpdate = NonZeroTime(m->timenow + mDNSPlatformOneSecond);
+ LogInfo("mDNSCoreMachineSleep waking: NextSRVUpdate in %d %d", m->NextSRVUpdate - m->timenow, m->timenow);
+
+ // 2. Re-validate our cache records
+ currtime = mDNSPlatformUTC();
+
+#if APPLE_OSX_mDNSResponder
+ // start time of this statistics gathering interval
+ m->StatStartTime = currtime;
+#endif // APPLE_OSX_mDNSResponder
+
+ diff = currtime - m->TimeSlept;
+ FORALL_CACHERECORDS(slot, cg, cr)
+ {
+ // Temporary fix: For unicast cache records, look at how much time we slept.
+ // Adjust the RecvTime by the amount of time we slept so that we age the
+ // cache record appropriately. If it is expired already, purge. If there
+ // is a network change that happens after the wakeup, we might purge the
+ // cache anyways and this helps only in the case where there are no network
+ // changes across sleep/wakeup transition.
+ //
+ // Note: If there is a network/DNS server change that already happened and
+ // these cache entries are already refreshed and we are getting a delayed
+ // wake up notification, we might adjust the TimeRcvd based on the time slept
+ // now which can cause the cache to purge pre-maturely. As this is not a very
+ // common case, this should happen rarely.
+ if (!cr->resrec.InterfaceID)
+ {
+ if (diff > 0)
+ {
+ mDNSu32 uTTL = RRUnadjustedTTL(cr->resrec.rroriginalttl);
+ const mDNSs32 remain = uTTL - (m->timenow - cr->TimeRcvd) / mDNSPlatformOneSecond;
+
+ // -if we have slept longer than the remaining TTL, purge and start fresh.
+ // -if we have been sleeping for a long time, we could reduce TimeRcvd below by
+ // a sufficiently big value which could cause the value to go into the future
+ // because of the signed comparison of time. For this to happen, we should have been
+ // sleeping really long (~24 days). For now, we want to be conservative and flush even
+ // if we have slept for more than two days.
+
+ if (diff >= remain || diff > (2 * 24 * 3600))
+ {
+ LogInfo("mDNSCoreMachineSleep: %s: Purging cache entry SleptTime %d, Remaining TTL %d",
+ CRDisplayString(m, cr), diff, remain);
+ mDNS_PurgeCacheResourceRecord(m, cr);
+ continue;
+ }
+ cr->TimeRcvd -= (diff * mDNSPlatformOneSecond);
+ if (m->timenow - (cr->TimeRcvd + ((mDNSs32)uTTL * mDNSPlatformOneSecond)) >= 0)
+ {
+ LogInfo("mDNSCoreMachineSleep: %s: Purging after adjusting the remaining TTL %d by %d seconds",
+ CRDisplayString(m, cr), remain, diff);
+ mDNS_PurgeCacheResourceRecord(m, cr);
+ }
+ else
+ {
+ LogInfo("mDNSCoreMachineSleep: %s: Adjusted the remain ttl %u by %d seconds", CRDisplayString(m, cr), remain, diff);
+ }
+ }
+ }
+ else
+ {
+ mDNS_Reconfirm_internal(m, cr, kDefaultReconfirmTimeForWake);
+ }
+ }
+
+ // 3. Retrigger probing and announcing for all our authoritative records
+ for (rr = m->ResourceRecords; rr; rr=rr->next)
+ {
+ if (AuthRecord_uDNS(rr))
+ {
+ ActivateUnicastRegistration(m, rr);
+ }
+ else
+ {
+ mDNSCoreRestartRegistration(m, rr, -1);
+ }
+ }
+
+ // 4. Refresh NAT mappings
+ // We don't want to have to assume that all hardware can necessarily keep accurate
+ // track of passage of time while asleep, so on wake we refresh our NAT mappings.
+ // We typically wake up with no interfaces active, so there's no need to rush to try to find our external address.
+ // But if we do get a network configuration change, mDNSMacOSXNetworkChanged will call uDNS_SetupDNSConfig, which
+ // will call mDNS_SetPrimaryInterfaceInfo, which will call RecreateNATMappings to refresh them, potentially sooner
+ // than five seconds from now.
+ LogInfo("mDNSCoreMachineSleep: recreating NAT mappings in 5 seconds");
+ RecreateNATMappings(m, mDNSPlatformOneSecond * 5);
+ mDNS_Unlock(m);
+ }
+}
mDNSexport mDNSBool mDNSCoreReadyForSleep(mDNS *m, mDNSs32 now)
- {
- DNSQuestion *q;
- AuthRecord *rr;
- NetworkInterfaceInfo *intf;
-
- mDNS_Lock(m);
-
- if (m->DelaySleep) goto notready;
-
- // If we've not hit the sleep limit time, and it's not time for our next retry, we can skip these checks
- if (m->SleepLimit - now > 0 && m->NextScheduledSPRetry - now > 0) goto notready;
-
- m->NextScheduledSPRetry = now + 0x40000000UL;
-
- // See if we might need to retransmit any lost Sleep Proxy Registrations
- for (intf = GetFirstActiveInterface(m->HostInterfaces); intf; intf = GetFirstActiveInterface(intf->next))
- if (intf->NextSPSAttempt >= 0)
- {
- if (now - intf->NextSPSAttemptTime >= 0)
- {
- LogSPS("mDNSCoreReadyForSleep: retrying for %s SPS %d try %d",
- intf->ifname, intf->NextSPSAttempt/3, intf->NextSPSAttempt);
- SendSPSRegistration(m, intf, zeroID);
- // Don't need to "goto notready" here, because if we do still have record registrations
- // that have not been acknowledged yet, we'll catch that in the record list scan below.
- }
- else
- if (m->NextScheduledSPRetry - intf->NextSPSAttemptTime > 0)
- m->NextScheduledSPRetry = intf->NextSPSAttemptTime;
- }
-
- // Scan list of interfaces, and see if we're still waiting for any sleep proxy resolves to complete
- for (intf = GetFirstActiveInterface(m->HostInterfaces); intf; intf = GetFirstActiveInterface(intf->next))
- {
- int sps = (intf->NextSPSAttempt == 0) ? 0 : (intf->NextSPSAttempt-1)/3;
- if (intf->NetWakeResolve[sps].ThisQInterval >= 0)
- {
- LogSPS("mDNSCoreReadyForSleep: waiting for SPS Resolve %s %##s (%s)",
- intf->ifname, intf->NetWakeResolve[sps].qname.c, DNSTypeName(intf->NetWakeResolve[sps].qtype));
- goto spsnotready;
- }
- }
-
- // Scan list of registered records
- for (rr = m->ResourceRecords; rr; rr = rr->next)
- if (!AuthRecord_uDNS(rr))
- if (!mDNSOpaque16IsZero(rr->updateid))
- { LogSPS("mDNSCoreReadyForSleep: waiting for SPS Update ID %d %s", mDNSVal16(rr->updateid), ARDisplayString(m,rr)); goto spsnotready; }
-
- // Scan list of private LLQs, and make sure they've all completed their handshake with the server
- for (q = m->Questions; q; q = q->next)
- if (!mDNSOpaque16IsZero(q->TargetQID) && q->LongLived && q->ReqLease == 0 && q->tcp)
- {
- LogSPS("mDNSCoreReadyForSleep: waiting for LLQ %##s (%s)", q->qname.c, DNSTypeName(q->qtype));
- goto notready;
- }
-
- // Scan list of registered records
- for (rr = m->ResourceRecords; rr; rr = rr->next)
- if (AuthRecord_uDNS(rr))
- {
- if (rr->state == regState_Refresh && rr->tcp)
- { LogSPS("mDNSCoreReadyForSleep: waiting for Record Update ID %d %s", mDNSVal16(rr->updateid), ARDisplayString(m,rr)); goto notready; }
- #if APPLE_OSX_mDNSResponder
- if (!RecordReadyForSleep(m, rr)) { LogSPS("mDNSCoreReadyForSleep: waiting for %s", ARDisplayString(m, rr)); goto notready; }
- #endif
- }
-
- mDNS_Unlock(m);
- return mDNStrue;
+{
+ DNSQuestion *q;
+ AuthRecord *rr;
+ NetworkInterfaceInfo *intf;
+
+ mDNS_Lock(m);
+
+ if (m->DelaySleep) goto notready;
+
+ // If we've not hit the sleep limit time, and it's not time for our next retry, we can skip these checks
+ if (m->SleepLimit - now > 0 && m->NextScheduledSPRetry - now > 0) goto notready;
+
+ m->NextScheduledSPRetry = now + 0x40000000UL;
+
+ // See if we might need to retransmit any lost Sleep Proxy Registrations
+ for (intf = GetFirstActiveInterface(m->HostInterfaces); intf; intf = GetFirstActiveInterface(intf->next))
+ if (intf->NextSPSAttempt >= 0)
+ {
+ if (now - intf->NextSPSAttemptTime >= 0)
+ {
+ LogSPS("mDNSCoreReadyForSleep: retrying for %s SPS %d try %d",
+ intf->ifname, intf->NextSPSAttempt/3, intf->NextSPSAttempt);
+ SendSPSRegistration(m, intf, zeroID);
+ // Don't need to "goto notready" here, because if we do still have record registrations
+ // that have not been acknowledged yet, we'll catch that in the record list scan below.
+ }
+ else
+ if (m->NextScheduledSPRetry - intf->NextSPSAttemptTime > 0)
+ m->NextScheduledSPRetry = intf->NextSPSAttemptTime;
+ }
+
+ // Scan list of interfaces, and see if we're still waiting for any sleep proxy resolves to complete
+ for (intf = GetFirstActiveInterface(m->HostInterfaces); intf; intf = GetFirstActiveInterface(intf->next))
+ {
+ int sps = (intf->NextSPSAttempt == 0) ? 0 : (intf->NextSPSAttempt-1)/3;
+ if (intf->NetWakeResolve[sps].ThisQInterval >= 0)
+ {
+ LogSPS("mDNSCoreReadyForSleep: waiting for SPS Resolve %s %##s (%s)",
+ intf->ifname, intf->NetWakeResolve[sps].qname.c, DNSTypeName(intf->NetWakeResolve[sps].qtype));
+ goto spsnotready;
+ }
+ }
+
+ // Scan list of registered records
+ for (rr = m->ResourceRecords; rr; rr = rr->next)
+ if (!AuthRecord_uDNS(rr))
+ if (!mDNSOpaque64IsZero(&rr->updateIntID))
+ { LogSPS("mDNSCoreReadyForSleep: waiting for SPS updateIntID 0x%x 0x%x (updateid %d) %s", rr->updateIntID.l[1], rr->updateIntID.l[0], mDNSVal16(rr->updateid), ARDisplayString(m,rr)); goto spsnotready; }
+
+ // Scan list of private LLQs, and make sure they've all completed their handshake with the server
+ for (q = m->Questions; q; q = q->next)
+ if (!mDNSOpaque16IsZero(q->TargetQID) && q->LongLived && q->ReqLease == 0 && q->tcp)
+ {
+ LogSPS("mDNSCoreReadyForSleep: waiting for LLQ %##s (%s)", q->qname.c, DNSTypeName(q->qtype));
+ goto notready;
+ }
+
+ // Scan list of registered records
+ for (rr = m->ResourceRecords; rr; rr = rr->next)
+ if (AuthRecord_uDNS(rr))
+ {
+ if (rr->state == regState_Refresh && rr->tcp)
+ { LogSPS("mDNSCoreReadyForSleep: waiting for Record updateIntID 0x%x 0x%x (updateid %d) %s", rr->updateIntID.l[1], rr->updateIntID.l[0], mDNSVal16(rr->updateid), ARDisplayString(m,rr)); goto notready; }
+ #if APPLE_OSX_mDNSResponder
+ if (!RecordReadyForSleep(m, rr)) { LogSPS("mDNSCoreReadyForSleep: waiting for %s", ARDisplayString(m, rr)); goto notready; }
+ #endif
+ }
+
+ mDNS_Unlock(m);
+ return mDNStrue;
spsnotready:
- // If we failed to complete sleep proxy registration within ten seconds, we give up on that
- // and allow up to ten seconds more to complete wide-area deregistration instead
- if (now - m->SleepLimit >= 0)
- {
- LogMsg("Failed to register with SPS, now sending goodbyes");
-
- for (intf = GetFirstActiveInterface(m->HostInterfaces); intf; intf = GetFirstActiveInterface(intf->next))
- if (intf->NetWakeBrowse.ThisQInterval >= 0)
- {
- LogSPS("ReadyForSleep mDNS_DeactivateNetWake %s %##s (%s)",
- intf->ifname, intf->NetWakeResolve[0].qname.c, DNSTypeName(intf->NetWakeResolve[0].qtype));
- mDNS_DeactivateNetWake_internal(m, intf);
- }
-
- for (rr = m->ResourceRecords; rr; rr = rr->next)
- if (!AuthRecord_uDNS(rr))
- if (!mDNSOpaque16IsZero(rr->updateid))
- {
- LogSPS("ReadyForSleep clearing updateid for %s", ARDisplayString(m, rr));
- rr->updateid = zeroID;
- }
-
- // We'd really like to allow up to ten seconds more here,
- // but if we don't respond to the sleep notification within 30 seconds
- // we'll be put back to sleep forcibly without the chance to schedule the next maintenance wake.
- // Right now we wait 16 sec after wake for all the interfaces to come up, then we wait up to 10 seconds
- // more for SPS resolves and record registrations to complete, which puts us at 26 seconds.
- // If we allow just one more second to send our goodbyes, that puts us at 27 seconds.
- m->SleepLimit = now + mDNSPlatformOneSecond * 1;
-
- SendSleepGoodbyes(m);
- }
+ // If we failed to complete sleep proxy registration within ten seconds, we give up on that
+ // and allow up to ten seconds more to complete wide-area deregistration instead
+ if (now - m->SleepLimit >= 0)
+ {
+ LogMsg("Failed to register with SPS, now sending goodbyes");
+
+ for (intf = GetFirstActiveInterface(m->HostInterfaces); intf; intf = GetFirstActiveInterface(intf->next))
+ if (intf->NetWakeBrowse.ThisQInterval >= 0)
+ {
+ LogSPS("ReadyForSleep mDNS_DeactivateNetWake %s %##s (%s)",
+ intf->ifname, intf->NetWakeResolve[0].qname.c, DNSTypeName(intf->NetWakeResolve[0].qtype));
+ mDNS_DeactivateNetWake_internal(m, intf);
+ }
+
+ for (rr = m->ResourceRecords; rr; rr = rr->next)
+ if (!AuthRecord_uDNS(rr))
+ if (!mDNSOpaque64IsZero(&rr->updateIntID))
+ {
+ LogSPS("ReadyForSleep clearing updateIntID 0x%x 0x%x (updateid %d) for %s", rr->updateIntID.l[1], rr->updateIntID.l[0], mDNSVal16(rr->updateid), ARDisplayString(m, rr));
+ rr->updateIntID = zeroOpaque64;
+ }
+
+ // We'd really like to allow up to ten seconds more here,
+ // but if we don't respond to the sleep notification within 30 seconds
+ // we'll be put back to sleep forcibly without the chance to schedule the next maintenance wake.
+ // Right now we wait 16 sec after wake for all the interfaces to come up, then we wait up to 10 seconds
+ // more for SPS resolves and record registrations to complete, which puts us at 26 seconds.
+ // If we allow just one more second to send our goodbyes, that puts us at 27 seconds.
+ m->SleepLimit = now + mDNSPlatformOneSecond * 1;
+
+ SendSleepGoodbyes(m, mDNStrue, mDNStrue);
+ }
notready:
- mDNS_Unlock(m);
- return mDNSfalse;
- }
+ mDNS_Unlock(m);
+ return mDNSfalse;
+}
mDNSexport mDNSs32 mDNSCoreIntervalToNextWake(mDNS *const m, mDNSs32 now)
- {
- AuthRecord *ar;
-
- // Even when we have no wake-on-LAN-capable interfaces, or we failed to find a sleep proxy, or we have other
- // failure scenarios, we still want to wake up in at most 120 minutes, to see if the network environment has changed.
- // E.g. we might wake up and find no wireless network because the base station got rebooted just at that moment,
- // and if that happens we don't want to just give up and go back to sleep and never try again.
- mDNSs32 e = now + (120 * 60 * mDNSPlatformOneSecond); // Sleep for at most 120 minutes
-
- NATTraversalInfo *nat;
- for (nat = m->NATTraversals; nat; nat=nat->next)
- if (nat->Protocol && nat->ExpiryTime && nat->ExpiryTime - now > mDNSPlatformOneSecond*4)
- {
- mDNSs32 t = nat->ExpiryTime - (nat->ExpiryTime - now) / 10; // Wake up when 90% of the way to the expiry time
- if (e - t > 0) e = t;
- LogSPS("ComputeWakeTime: %p %s Int %5d Ext %5d Err %d Retry %5d Interval %5d Expire %5d Wake %5d",
- nat, nat->Protocol == NATOp_MapTCP ? "TCP" : "UDP",
- mDNSVal16(nat->IntPort), mDNSVal16(nat->ExternalPort), nat->Result,
- nat->retryPortMap ? (nat->retryPortMap - now) / mDNSPlatformOneSecond : 0,
- nat->retryInterval / mDNSPlatformOneSecond,
- nat->ExpiryTime ? (nat->ExpiryTime - now) / mDNSPlatformOneSecond : 0,
- (t - now) / mDNSPlatformOneSecond);
- }
-
- // This loop checks both the time we need to renew wide-area registrations,
- // and the time we need to renew Sleep Proxy registrations
- for (ar = m->ResourceRecords; ar; ar = ar->next)
- if (ar->expire && ar->expire - now > mDNSPlatformOneSecond*4)
- {
- mDNSs32 t = ar->expire - (ar->expire - now) / 10; // Wake up when 90% of the way to the expiry time
- if (e - t > 0) e = t;
- LogSPS("ComputeWakeTime: %p Int %7d Next %7d Expire %7d Wake %7d %s",
- ar, ar->ThisAPInterval / mDNSPlatformOneSecond,
- (ar->LastAPTime + ar->ThisAPInterval - now) / mDNSPlatformOneSecond,
- ar->expire ? (ar->expire - now) / mDNSPlatformOneSecond : 0,
- (t - now) / mDNSPlatformOneSecond, ARDisplayString(m, ar));
- }
-
- return(e - now);
- }
+{
+ AuthRecord *ar;
+
+ // Even when we have no wake-on-LAN-capable interfaces, or we failed to find a sleep proxy, or we have other
+ // failure scenarios, we still want to wake up in at most 120 minutes, to see if the network environment has changed.
+ // E.g. we might wake up and find no wireless network because the base station got rebooted just at that moment,
+ // and if that happens we don't want to just give up and go back to sleep and never try again.
+ mDNSs32 e = now + (120 * 60 * mDNSPlatformOneSecond); // Sleep for at most 120 minutes
+
+ NATTraversalInfo *nat;
+ for (nat = m->NATTraversals; nat; nat=nat->next)
+ if (nat->Protocol && nat->ExpiryTime && nat->ExpiryTime - now > mDNSPlatformOneSecond*4)
+ {
+ mDNSs32 t = nat->ExpiryTime - (nat->ExpiryTime - now) / 10; // Wake up when 90% of the way to the expiry time
+ if (e - t > 0) e = t;
+ LogSPS("ComputeWakeTime: %p %s Int %5d Ext %5d Err %d Retry %5d Interval %5d Expire %5d Wake %5d",
+ nat, nat->Protocol == NATOp_MapTCP ? "TCP" : "UDP",
+ mDNSVal16(nat->IntPort), mDNSVal16(nat->ExternalPort), nat->Result,
+ nat->retryPortMap ? (nat->retryPortMap - now) / mDNSPlatformOneSecond : 0,
+ nat->retryInterval / mDNSPlatformOneSecond,
+ nat->ExpiryTime ? (nat->ExpiryTime - now) / mDNSPlatformOneSecond : 0,
+ (t - now) / mDNSPlatformOneSecond);
+ }
+
+ // This loop checks both the time we need to renew wide-area registrations,
+ // and the time we need to renew Sleep Proxy registrations
+ for (ar = m->ResourceRecords; ar; ar = ar->next)
+ if (ar->expire && ar->expire - now > mDNSPlatformOneSecond*4)
+ {
+ mDNSs32 t = ar->expire - (ar->expire - now) / 10; // Wake up when 90% of the way to the expiry time
+ if (e - t > 0) e = t;
+ LogSPS("ComputeWakeTime: %p Int %7d Next %7d Expire %7d Wake %7d %s",
+ ar, ar->ThisAPInterval / mDNSPlatformOneSecond,
+ (ar->LastAPTime + ar->ThisAPInterval - now) / mDNSPlatformOneSecond,
+ ar->expire ? (ar->expire - now) / mDNSPlatformOneSecond : 0,
+ (t - now) / mDNSPlatformOneSecond, ARDisplayString(m, ar));
+ }
+
+ return(e - now);
+}
// ***************************************************************************
#if COMPILER_LIKES_PRAGMA_MARK
#define MustSendRecord(RR) ((RR)->NR_AnswerTo || (RR)->NR_AdditionalTo)
mDNSlocal mDNSu8 *GenerateUnicastResponse(const DNSMessage *const query, const mDNSu8 *const end,
- const mDNSInterfaceID InterfaceID, mDNSBool LegacyQuery, DNSMessage *const response, AuthRecord *ResponseRecords)
- {
- mDNSu8 *responseptr = response->data;
- const mDNSu8 *const limit = response->data + sizeof(response->data);
- const mDNSu8 *ptr = query->data;
- AuthRecord *rr;
- mDNSu32 maxttl = 0x70000000;
- int i;
-
- // Initialize the response fields so we can answer the questions
- InitializeDNSMessage(&response->h, query->h.id, ResponseFlags);
-
- // ***
- // *** 1. Write out the list of questions we are actually going to answer with this packet
- // ***
- if (LegacyQuery)
- {
- maxttl = kStaticCacheTTL;
- for (i=0; i<query->h.numQuestions; i++) // For each question...
- {
- DNSQuestion q;
- ptr = getQuestion(query, ptr, end, InterfaceID, &q); // get the question...
- if (!ptr) return(mDNSNULL);
-
- for (rr=ResponseRecords; rr; rr=rr->NextResponse) // and search our list of proposed answers
- {
- if (rr->NR_AnswerTo == ptr) // If we're going to generate a record answering this question
- { // then put the question in the question section
- responseptr = putQuestion(response, responseptr, limit, &q.qname, q.qtype, q.qclass);
- if (!responseptr) { debugf("GenerateUnicastResponse: Ran out of space for questions!"); return(mDNSNULL); }
- break; // break out of the ResponseRecords loop, and go on to the next question
- }
- }
- }
-
- if (response->h.numQuestions == 0) { LogMsg("GenerateUnicastResponse: ERROR! Why no questions?"); return(mDNSNULL); }
- }
-
- // ***
- // *** 2. Write Answers
- // ***
- for (rr=ResponseRecords; rr; rr=rr->NextResponse)
- if (rr->NR_AnswerTo)
- {
- mDNSu8 *p = PutResourceRecordTTL(response, responseptr, &response->h.numAnswers, &rr->resrec,
- maxttl < rr->resrec.rroriginalttl ? maxttl : rr->resrec.rroriginalttl);
- if (p) responseptr = p;
- else { debugf("GenerateUnicastResponse: Ran out of space for answers!"); response->h.flags.b[0] |= kDNSFlag0_TC; }
- }
-
- // ***
- // *** 3. Write Additionals
- // ***
- for (rr=ResponseRecords; rr; rr=rr->NextResponse)
- if (rr->NR_AdditionalTo && !rr->NR_AnswerTo)
- {
- mDNSu8 *p = PutResourceRecordTTL(response, responseptr, &response->h.numAdditionals, &rr->resrec,
- maxttl < rr->resrec.rroriginalttl ? maxttl : rr->resrec.rroriginalttl);
- if (p) responseptr = p;
- else debugf("GenerateUnicastResponse: No more space for additionals");
- }
-
- return(responseptr);
- }
+ const mDNSInterfaceID InterfaceID, mDNSBool LegacyQuery, DNSMessage *const response, AuthRecord *ResponseRecords)
+{
+ mDNSu8 *responseptr = response->data;
+ const mDNSu8 *const limit = response->data + sizeof(response->data);
+ const mDNSu8 *ptr = query->data;
+ AuthRecord *rr;
+ mDNSu32 maxttl = 0x70000000;
+ int i;
+
+ // Initialize the response fields so we can answer the questions
+ InitializeDNSMessage(&response->h, query->h.id, ResponseFlags);
+
+ // ***
+ // *** 1. Write out the list of questions we are actually going to answer with this packet
+ // ***
+ if (LegacyQuery)
+ {
+ maxttl = kStaticCacheTTL;
+ for (i=0; i<query->h.numQuestions; i++) // For each question...
+ {
+ DNSQuestion q;
+ ptr = getQuestion(query, ptr, end, InterfaceID, &q); // get the question...
+ if (!ptr) return(mDNSNULL);
+
+ for (rr=ResponseRecords; rr; rr=rr->NextResponse) // and search our list of proposed answers
+ {
+ if (rr->NR_AnswerTo == ptr) // If we're going to generate a record answering this question
+ { // then put the question in the question section
+ responseptr = putQuestion(response, responseptr, limit, &q.qname, q.qtype, q.qclass);
+ if (!responseptr) { debugf("GenerateUnicastResponse: Ran out of space for questions!"); return(mDNSNULL); }
+ break; // break out of the ResponseRecords loop, and go on to the next question
+ }
+ }
+ }
+
+ if (response->h.numQuestions == 0) { LogMsg("GenerateUnicastResponse: ERROR! Why no questions?"); return(mDNSNULL); }
+ }
+
+ // ***
+ // *** 2. Write Answers
+ // ***
+ for (rr=ResponseRecords; rr; rr=rr->NextResponse)
+ if (rr->NR_AnswerTo)
+ {
+ mDNSu8 *p = PutResourceRecordTTL(response, responseptr, &response->h.numAnswers, &rr->resrec,
+ maxttl < rr->resrec.rroriginalttl ? maxttl : rr->resrec.rroriginalttl);
+ if (p) responseptr = p;
+ else { debugf("GenerateUnicastResponse: Ran out of space for answers!"); response->h.flags.b[0] |= kDNSFlag0_TC; }
+ }
+
+ // ***
+ // *** 3. Write Additionals
+ // ***
+ for (rr=ResponseRecords; rr; rr=rr->NextResponse)
+ if (rr->NR_AdditionalTo && !rr->NR_AnswerTo)
+ {
+ mDNSu8 *p = PutResourceRecordTTL(response, responseptr, &response->h.numAdditionals, &rr->resrec,
+ maxttl < rr->resrec.rroriginalttl ? maxttl : rr->resrec.rroriginalttl);
+ if (p) responseptr = p;
+ else debugf("GenerateUnicastResponse: No more space for additionals");
+ }
+
+ return(responseptr);
+}
// AuthRecord *our is our Resource Record
// CacheRecord *pkt is the Resource Record from the response packet we've witnessed on the network
// Returns +1 if there was a conflict and we won
// Returns -1 if there was a conflict and we lost and have to rename
mDNSlocal int CompareRData(const AuthRecord *const our, const CacheRecord *const pkt)
- {
- mDNSu8 ourdata[256], *ourptr = ourdata, *ourend;
- mDNSu8 pktdata[256], *pktptr = pktdata, *pktend;
- if (!our) { LogMsg("CompareRData ERROR: our is NULL"); return(+1); }
- if (!pkt) { LogMsg("CompareRData ERROR: pkt is NULL"); return(+1); }
-
- ourend = putRData(mDNSNULL, ourdata, ourdata + sizeof(ourdata), &our->resrec);
- pktend = putRData(mDNSNULL, pktdata, pktdata + sizeof(pktdata), &pkt->resrec);
- while (ourptr < ourend && pktptr < pktend && *ourptr == *pktptr) { ourptr++; pktptr++; }
- if (ourptr >= ourend && pktptr >= pktend) return(0); // If data identical, not a conflict
-
- if (ourptr >= ourend) return(-1); // Our data ran out first; We lost
- if (pktptr >= pktend) return(+1); // Packet data ran out first; We won
- if (*pktptr > *ourptr) return(-1); // Our data is numerically lower; We lost
- if (*pktptr < *ourptr) return(+1); // Packet data is numerically lower; We won
-
- LogMsg("CompareRData ERROR: Invalid state");
- return(-1);
- }
+{
+ mDNSu8 ourdata[256], *ourptr = ourdata, *ourend;
+ mDNSu8 pktdata[256], *pktptr = pktdata, *pktend;
+ if (!our) { LogMsg("CompareRData ERROR: our is NULL"); return(+1); }
+ if (!pkt) { LogMsg("CompareRData ERROR: pkt is NULL"); return(+1); }
+
+ ourend = putRData(mDNSNULL, ourdata, ourdata + sizeof(ourdata), &our->resrec);
+ pktend = putRData(mDNSNULL, pktdata, pktdata + sizeof(pktdata), &pkt->resrec);
+ while (ourptr < ourend && pktptr < pktend && *ourptr == *pktptr) { ourptr++; pktptr++; }
+ if (ourptr >= ourend && pktptr >= pktend) return(0); // If data identical, not a conflict
+
+ if (ourptr >= ourend) return(-1); // Our data ran out first; We lost
+ if (pktptr >= pktend) return(+1); // Packet data ran out first; We won
+ if (*pktptr > *ourptr) return(-1); // Our data is numerically lower; We lost
+ if (*pktptr < *ourptr) return(+1); // Packet data is numerically lower; We won
+
+ LogMsg("CompareRData ERROR: Invalid state");
+ return(-1);
+}
// See if we have an authoritative record that's identical to this packet record,
// whose canonical DependentOn record is the specified master record.
// If the record has no DependentOn, then just return that record's pointer
// Returns NULL if we don't have any local RRs that are identical to the one from the packet
mDNSlocal mDNSBool MatchDependentOn(const mDNS *const m, const CacheRecord *const pktrr, const AuthRecord *const master)
- {
- const AuthRecord *r1;
- for (r1 = m->ResourceRecords; r1; r1=r1->next)
- {
- if (IdenticalResourceRecord(&r1->resrec, &pktrr->resrec))
- {
- const AuthRecord *r2 = r1;
- while (r2->DependentOn) r2 = r2->DependentOn;
- if (r2 == master) return(mDNStrue);
- }
- }
- for (r1 = m->DuplicateRecords; r1; r1=r1->next)
- {
- if (IdenticalResourceRecord(&r1->resrec, &pktrr->resrec))
- {
- const AuthRecord *r2 = r1;
- while (r2->DependentOn) r2 = r2->DependentOn;
- if (r2 == master) return(mDNStrue);
- }
- }
- return(mDNSfalse);
- }
+{
+ const AuthRecord *r1;
+ for (r1 = m->ResourceRecords; r1; r1=r1->next)
+ {
+ if (IdenticalResourceRecord(&r1->resrec, &pktrr->resrec))
+ {
+ const AuthRecord *r2 = r1;
+ while (r2->DependentOn) r2 = r2->DependentOn;
+ if (r2 == master) return(mDNStrue);
+ }
+ }
+ for (r1 = m->DuplicateRecords; r1; r1=r1->next)
+ {
+ if (IdenticalResourceRecord(&r1->resrec, &pktrr->resrec))
+ {
+ const AuthRecord *r2 = r1;
+ while (r2->DependentOn) r2 = r2->DependentOn;
+ if (r2 == master) return(mDNStrue);
+ }
+ }
+ return(mDNSfalse);
+}
// Find the canonical RRSet pointer for this RR received in a packet.
// If we find any identical AuthRecord in our authoritative list, then follow its RRSet
// pointers (if any) to make sure we return the canonical member of this name/type/class
// Returns NULL if we don't have any local RRs that are identical to the one from the packet
mDNSlocal const AuthRecord *FindRRSet(const mDNS *const m, const CacheRecord *const pktrr)
- {
- const AuthRecord *rr;
- for (rr = m->ResourceRecords; rr; rr=rr->next)
- {
- if (IdenticalResourceRecord(&rr->resrec, &pktrr->resrec))
- {
- while (rr->RRSet && rr != rr->RRSet) rr = rr->RRSet;
- return(rr);
- }
- }
- return(mDNSNULL);
- }
+{
+ const AuthRecord *rr;
+ for (rr = m->ResourceRecords; rr; rr=rr->next)
+ {
+ if (IdenticalResourceRecord(&rr->resrec, &pktrr->resrec))
+ {
+ while (rr->RRSet && rr != rr->RRSet) rr = rr->RRSet;
+ return(rr);
+ }
+ }
+ return(mDNSNULL);
+}
// PacketRRConflict is called when we've received an RR (pktrr) which has the same name
// as one of our records (our) but different rdata.
// 3. If we have some *other* RR that exactly matches the one from the packet, and that record and our record
// are members of the same RRSet, then this is not a conflict.
mDNSlocal mDNSBool PacketRRConflict(const mDNS *const m, const AuthRecord *const our, const CacheRecord *const pktrr)
- {
- // If not supposed to be unique, not a conflict
- if (!(our->resrec.RecordType & kDNSRecordTypeUniqueMask)) return(mDNSfalse);
+{
+ // If not supposed to be unique, not a conflict
+ if (!(our->resrec.RecordType & kDNSRecordTypeUniqueMask)) return(mDNSfalse);
- // If a dependent record, not a conflict
- if (our->DependentOn || MatchDependentOn(m, pktrr, our)) return(mDNSfalse);
- else
- {
- // If the pktrr matches a member of ourset, not a conflict
- const AuthRecord *ourset = our->RRSet ? our->RRSet : our;
- const AuthRecord *pktset = FindRRSet(m, pktrr);
- if (pktset == ourset) return(mDNSfalse);
-
- // For records we're proxying, where we don't know the full
- // relationship between the records, having any matching record
- // in our AuthRecords list is sufficient evidence of non-conflict
- if (our->WakeUp.HMAC.l[0] && pktset) return(mDNSfalse);
- }
-
- // Okay, this is a conflict
- return(mDNStrue);
- }
+ // If a dependent record, not a conflict
+ if (our->DependentOn || MatchDependentOn(m, pktrr, our)) return(mDNSfalse);
+ else
+ {
+ // If the pktrr matches a member of ourset, not a conflict
+ const AuthRecord *ourset = our->RRSet ? our->RRSet : our;
+ const AuthRecord *pktset = FindRRSet(m, pktrr);
+ if (pktset == ourset) return(mDNSfalse);
+
+ // For records we're proxying, where we don't know the full
+ // relationship between the records, having any matching record
+ // in our AuthRecords list is sufficient evidence of non-conflict
+ if (our->WakeUp.HMAC.l[0] && pktset) return(mDNSfalse);
+ }
+
+ // Okay, this is a conflict
+ return(mDNStrue);
+}
// Note: ResolveSimultaneousProbe calls mDNS_Deregister_internal which can call a user callback, which may change
// the record list and/or question list.
// Any code walking either list must use the CurrentQuestion and/or CurrentRecord mechanism to protect against this.
mDNSlocal void ResolveSimultaneousProbe(mDNS *const m, const DNSMessage *const query, const mDNSu8 *const end,
- DNSQuestion *q, AuthRecord *our)
- {
- int i;
- const mDNSu8 *ptr = LocateAuthorities(query, end);
- mDNSBool FoundUpdate = mDNSfalse;
-
- for (i = 0; i < query->h.numAuthorities; i++)
- {
- ptr = GetLargeResourceRecord(m, query, ptr, end, q->InterfaceID, kDNSRecordTypePacketAuth, &m->rec);
- if (!ptr) break;
- if (m->rec.r.resrec.RecordType != kDNSRecordTypePacketNegative && ResourceRecordAnswersQuestion(&m->rec.r.resrec, q))
- {
- FoundUpdate = mDNStrue;
- if (PacketRRConflict(m, our, &m->rec.r))
- {
- int result = (int)our->resrec.rrclass - (int)m->rec.r.resrec.rrclass;
- if (!result) result = (int)our->resrec.rrtype - (int)m->rec.r.resrec.rrtype;
- if (!result) result = CompareRData(our, &m->rec.r);
- if (result)
- {
- const char *const msg = (result < 0) ? "lost:" : (result > 0) ? "won: " : "tie: ";
- LogMsg("ResolveSimultaneousProbe: %p Pkt Record: %08lX %s", q->InterfaceID, m->rec.r.resrec.rdatahash, CRDisplayString(m, &m->rec.r));
- LogMsg("ResolveSimultaneousProbe: %p Our Record %d %s %08lX %s", our->resrec.InterfaceID, our->ProbeCount, msg, our->resrec.rdatahash, ARDisplayString(m, our));
- }
- // If we lost the tie-break for simultaneous probes, we don't immediately give up, because we might be seeing stale packets on the network.
- // Instead we pause for one second, to give the other host (if real) a chance to establish its name, and then try probing again.
- // If there really is another live host out there with the same name, it will answer our probes and we'll then rename.
- if (result < 0)
- {
- m->SuppressProbes = NonZeroTime(m->timenow + mDNSPlatformOneSecond);
- our->ProbeCount = DefaultProbeCountForTypeUnique;
- our->AnnounceCount = InitialAnnounceCount;
- InitializeLastAPTime(m, our);
- goto exit;
- }
- }
+ DNSQuestion *q, AuthRecord *our)
+{
+ int i;
+ const mDNSu8 *ptr = LocateAuthorities(query, end);
+ mDNSBool FoundUpdate = mDNSfalse;
+
+ for (i = 0; i < query->h.numAuthorities; i++)
+ {
+ ptr = GetLargeResourceRecord(m, query, ptr, end, q->InterfaceID, kDNSRecordTypePacketAuth, &m->rec);
+ if (!ptr) break;
+ if (m->rec.r.resrec.RecordType != kDNSRecordTypePacketNegative && ResourceRecordAnswersQuestion(&m->rec.r.resrec, q))
+ {
+ FoundUpdate = mDNStrue;
+ if (PacketRRConflict(m, our, &m->rec.r))
+ {
+ int result = (int)our->resrec.rrclass - (int)m->rec.r.resrec.rrclass;
+ if (!result) result = (int)our->resrec.rrtype - (int)m->rec.r.resrec.rrtype;
+ if (!result) result = CompareRData(our, &m->rec.r);
+ if (result)
+ {
+ const char *const msg = (result < 0) ? "lost:" : (result > 0) ? "won: " : "tie: ";
+ LogMsg("ResolveSimultaneousProbe: %p Pkt Record: %08lX %s", q->InterfaceID, m->rec.r.resrec.rdatahash, CRDisplayString(m, &m->rec.r));
+ LogMsg("ResolveSimultaneousProbe: %p Our Record %d %s %08lX %s", our->resrec.InterfaceID, our->ProbeCount, msg, our->resrec.rdatahash, ARDisplayString(m, our));
+ }
+ // If we lost the tie-break for simultaneous probes, we don't immediately give up, because we might be seeing stale packets on the network.
+ // Instead we pause for one second, to give the other host (if real) a chance to establish its name, and then try probing again.
+ // If there really is another live host out there with the same name, it will answer our probes and we'll then rename.
+ if (result < 0)
+ {
+ m->SuppressProbes = NonZeroTime(m->timenow + mDNSPlatformOneSecond);
+ our->ProbeCount = DefaultProbeCountForTypeUnique;
+ our->AnnounceCount = InitialAnnounceCount;
+ InitializeLastAPTime(m, our);
+ goto exit;
+ }
+ }
#if 0
- else
- {
- LogMsg("ResolveSimultaneousProbe: %p Pkt Record: %08lX %s", q->InterfaceID, m->rec.r.resrec.rdatahash, CRDisplayString(m, &m->rec.r));
- LogMsg("ResolveSimultaneousProbe: %p Our Record %d ign: %08lX %s", our->resrec.InterfaceID, our->ProbeCount, our->resrec.rdatahash, ARDisplayString(m, our));
- }
+ else
+ {
+ LogMsg("ResolveSimultaneousProbe: %p Pkt Record: %08lX %s", q->InterfaceID, m->rec.r.resrec.rdatahash, CRDisplayString(m, &m->rec.r));
+ LogMsg("ResolveSimultaneousProbe: %p Our Record %d ign: %08lX %s", our->resrec.InterfaceID, our->ProbeCount, our->resrec.rdatahash, ARDisplayString(m, our));
+ }
#endif
- }
- m->rec.r.resrec.RecordType = 0; // Clear RecordType to show we're not still using it
- }
- if (!FoundUpdate)
- LogInfo("ResolveSimultaneousProbe: %##s (%s): No Update Record found", our->resrec.name->c, DNSTypeName(our->resrec.rrtype));
+ }
+ m->rec.r.resrec.RecordType = 0; // Clear RecordType to show we're not still using it
+ }
+ if (!FoundUpdate)
+ LogInfo("ResolveSimultaneousProbe: %##s (%s): No Update Record found", our->resrec.name->c, DNSTypeName(our->resrec.rrtype));
exit:
- m->rec.r.resrec.RecordType = 0; // Clear RecordType to show we're not still using it
- }
+ m->rec.r.resrec.RecordType = 0; // Clear RecordType to show we're not still using it
+}
mDNSlocal CacheRecord *FindIdenticalRecordInCache(const mDNS *const m, const ResourceRecord *const pktrr)
- {
- mDNSu32 slot = HashSlot(pktrr->name);
- CacheGroup *cg = CacheGroupForRecord(m, slot, pktrr);
- CacheRecord *rr;
- mDNSBool match;
- for (rr = cg ? cg->members : mDNSNULL; rr; rr=rr->next)
- {
- match = !pktrr->InterfaceID ? pktrr->rDNSServer == rr->resrec.rDNSServer : pktrr->InterfaceID == rr->resrec.InterfaceID;
- if (match && IdenticalSameNameRecord(pktrr, &rr->resrec)) break;
- }
- return(rr);
- }
+{
+ mDNSu32 slot = HashSlot(pktrr->name);
+ CacheGroup *cg = CacheGroupForRecord(m, slot, pktrr);
+ CacheRecord *rr;
+ mDNSBool match;
+ for (rr = cg ? cg->members : mDNSNULL; rr; rr=rr->next)
+ {
+ if (!pktrr->InterfaceID)
+ {
+ mDNSu16 id1 = (pktrr->rDNSServer ? pktrr->rDNSServer->resGroupID : 0);
+ mDNSu16 id2 = (rr->resrec.rDNSServer ? rr->resrec.rDNSServer->resGroupID : 0);
+ match = (id1 == id2);
+ }
+ else match = (pktrr->InterfaceID == rr->resrec.InterfaceID);
+
+ if (match && IdenticalSameNameRecord(pktrr, &rr->resrec)) break;
+ }
+ return(rr);
+}
+mDNSlocal void DeregisterProxyRecord(mDNS *const m, AuthRecord *const rr)
+{
+ rr->WakeUp.HMAC = zeroEthAddr; // Clear HMAC so that mDNS_Deregister_internal doesn't waste packets trying to wake this host
+ rr->RequireGoodbye = mDNSfalse; // and we don't want to send goodbye for it
+ mDNS_Deregister_internal(m, rr, mDNS_Dereg_normal);
+ SetSPSProxyListChanged(m->rec.r.resrec.InterfaceID);
+}
+
+mDNSlocal void ClearKeepaliveProxyRecords(mDNS *const m, const OwnerOptData *const owner, AuthRecord *const thelist, const mDNSInterfaceID InterfaceID)
+{
+ if (m->CurrentRecord)
+ LogMsg("ClearIdenticalProxyRecords ERROR m->CurrentRecord already set %s", ARDisplayString(m, m->CurrentRecord));
+ m->CurrentRecord = thelist;
+
+ // Normally, the RDATA of the keepalive record will be different each time and hence we always
+ // clean up the keepalive record.
+ while (m->CurrentRecord)
+ {
+ AuthRecord *const rr = m->CurrentRecord;
+ if (InterfaceID == rr->resrec.InterfaceID && mDNSSameEthAddress(&owner->HMAC, &rr->WakeUp.HMAC))
+ {
+ if (mDNS_KeepaliveRecord(&m->rec.r.resrec))
+ {
+ LogSPS("ClearKeepaliveProxyRecords: Removing %3d H-MAC %.6a I-MAC %.6a %d %d %s",
+ m->ProxyRecords, &rr->WakeUp.HMAC, &rr->WakeUp.IMAC, rr->WakeUp.seq, owner->seq, ARDisplayString(m, rr));
+ DeregisterProxyRecord(m, rr);
+ }
+ }
+ // Mustn't advance m->CurrentRecord until *after* mDNS_Deregister_internal, because
+ // new records could have been added to the end of the list as a result of that call.
+ if (m->CurrentRecord == rr) // If m->CurrentRecord was not advanced for us, do it now
+ m->CurrentRecord = rr->next;
+ }
+}
// Called from mDNSCoreReceiveUpdate when we get a sleep proxy registration request,
// to check our lists and discard any stale duplicates of this record we already have
mDNSlocal void ClearIdenticalProxyRecords(mDNS *const m, const OwnerOptData *const owner, AuthRecord *const thelist)
- {
- if (m->CurrentRecord)
- LogMsg("ClearIdenticalProxyRecords ERROR m->CurrentRecord already set %s", ARDisplayString(m, m->CurrentRecord));
- m->CurrentRecord = thelist;
- while (m->CurrentRecord)
- {
- AuthRecord *const rr = m->CurrentRecord;
- if (m->rec.r.resrec.InterfaceID == rr->resrec.InterfaceID && mDNSSameEthAddress(&owner->HMAC, &rr->WakeUp.HMAC))
- if (IdenticalResourceRecord(&rr->resrec, &m->rec.r.resrec))
- {
- LogSPS("ClearIdenticalProxyRecords: Removing %3d H-MAC %.6a I-MAC %.6a %d %d %s",
- m->ProxyRecords, &rr->WakeUp.HMAC, &rr->WakeUp.IMAC, rr->WakeUp.seq, owner->seq, ARDisplayString(m, rr));
- rr->WakeUp.HMAC = zeroEthAddr; // Clear HMAC so that mDNS_Deregister_internal doesn't waste packets trying to wake this host
- rr->RequireGoodbye = mDNSfalse; // and we don't want to send goodbye for it
- mDNS_Deregister_internal(m, rr, mDNS_Dereg_normal);
- SetSPSProxyListChanged(m->rec.r.resrec.InterfaceID);
- }
- // Mustn't advance m->CurrentRecord until *after* mDNS_Deregister_internal, because
- // new records could have been added to the end of the list as a result of that call.
- if (m->CurrentRecord == rr) // If m->CurrentRecord was not advanced for us, do it now
- m->CurrentRecord = rr->next;
- }
- }
+{
+ if (m->CurrentRecord)
+ LogMsg("ClearIdenticalProxyRecords ERROR m->CurrentRecord already set %s", ARDisplayString(m, m->CurrentRecord));
+ m->CurrentRecord = thelist;
+ while (m->CurrentRecord)
+ {
+ AuthRecord *const rr = m->CurrentRecord;
+ if (m->rec.r.resrec.InterfaceID == rr->resrec.InterfaceID && mDNSSameEthAddress(&owner->HMAC, &rr->WakeUp.HMAC))
+ if (IdenticalResourceRecord(&rr->resrec, &m->rec.r.resrec))
+ {
+ LogSPS("ClearIdenticalProxyRecords: Removing %3d H-MAC %.6a I-MAC %.6a %d %d %s",
+ m->ProxyRecords, &rr->WakeUp.HMAC, &rr->WakeUp.IMAC, rr->WakeUp.seq, owner->seq, ARDisplayString(m, rr));
+ DeregisterProxyRecord(m, rr);
+ }
+ // Mustn't advance m->CurrentRecord until *after* mDNS_Deregister_internal, because
+ // new records could have been added to the end of the list as a result of that call.
+ if (m->CurrentRecord == rr) // If m->CurrentRecord was not advanced for us, do it now
+ m->CurrentRecord = rr->next;
+ }
+}
// Called from ProcessQuery when we get an mDNS packet with an owner record in it
mDNSlocal void ClearProxyRecords(mDNS *const m, const OwnerOptData *const owner, AuthRecord *const thelist)
- {
- if (m->CurrentRecord)
- LogMsg("ClearProxyRecords ERROR m->CurrentRecord already set %s", ARDisplayString(m, m->CurrentRecord));
- m->CurrentRecord = thelist;
- while (m->CurrentRecord)
- {
- AuthRecord *const rr = m->CurrentRecord;
- if (m->rec.r.resrec.InterfaceID == rr->resrec.InterfaceID && mDNSSameEthAddress(&owner->HMAC, &rr->WakeUp.HMAC))
- if (owner->seq != rr->WakeUp.seq || m->timenow - rr->TimeRcvd > mDNSPlatformOneSecond * 60)
- {
- if (rr->AddressProxy.type == mDNSAddrType_IPv6)
- {
- // We don't do this here because we know that the host is waking up at this point, so we don't send
- // Unsolicited Neighbor Advertisements -- even Neighbor Advertisements agreeing with what the host should be
- // saying itself -- because it can cause some IPv6 stacks to falsely conclude that there's an address conflict.
- #if MDNS_USE_Unsolicited_Neighbor_Advertisements
- LogSPS("NDP Announcement -- Releasing traffic for H-MAC %.6a I-MAC %.6a %s",
- &rr->WakeUp.HMAC, &rr->WakeUp.IMAC, ARDisplayString(m,rr));
- SendNDP(m, NDP_Adv, NDP_Override, rr, &rr->AddressProxy.ip.v6, &rr->WakeUp.IMAC, &AllHosts_v6, &AllHosts_v6_Eth);
- #endif
- }
- LogSPS("ClearProxyRecords: Removing %3d AC %2d %02X H-MAC %.6a I-MAC %.6a %d %d %s",
- m->ProxyRecords, rr->AnnounceCount, rr->resrec.RecordType,
- &rr->WakeUp.HMAC, &rr->WakeUp.IMAC, rr->WakeUp.seq, owner->seq, ARDisplayString(m, rr));
- if (rr->resrec.RecordType == kDNSRecordTypeDeregistering) rr->resrec.RecordType = kDNSRecordTypeShared;
- rr->WakeUp.HMAC = zeroEthAddr; // Clear HMAC so that mDNS_Deregister_internal doesn't waste packets trying to wake this host
- rr->RequireGoodbye = mDNSfalse; // and we don't want to send goodbye for it, since real host is now back and functional
- mDNS_Deregister_internal(m, rr, mDNS_Dereg_normal);
- SetSPSProxyListChanged(m->rec.r.resrec.InterfaceID);
- }
- // Mustn't advance m->CurrentRecord until *after* mDNS_Deregister_internal, because
- // new records could have been added to the end of the list as a result of that call.
- if (m->CurrentRecord == rr) // If m->CurrentRecord was not advanced for us, do it now
- m->CurrentRecord = rr->next;
- }
- }
+{
+ if (m->CurrentRecord)
+ LogMsg("ClearProxyRecords ERROR m->CurrentRecord already set %s", ARDisplayString(m, m->CurrentRecord));
+ m->CurrentRecord = thelist;
+ while (m->CurrentRecord)
+ {
+ AuthRecord *const rr = m->CurrentRecord;
+ if (m->rec.r.resrec.InterfaceID == rr->resrec.InterfaceID && mDNSSameEthAddress(&owner->HMAC, &rr->WakeUp.HMAC))
+ if (owner->seq != rr->WakeUp.seq || m->timenow - rr->TimeRcvd > mDNSPlatformOneSecond * 60)
+ {
+ if (rr->AddressProxy.type == mDNSAddrType_IPv6)
+ {
+ // We don't do this here because we know that the host is waking up at this point, so we don't send
+ // Unsolicited Neighbor Advertisements -- even Neighbor Advertisements agreeing with what the host should be
+ // saying itself -- because it can cause some IPv6 stacks to falsely conclude that there's an address conflict.
+ #if MDNS_USE_Unsolicited_Neighbor_Advertisements
+ LogSPS("NDP Announcement -- Releasing traffic for H-MAC %.6a I-MAC %.6a %s",
+ &rr->WakeUp.HMAC, &rr->WakeUp.IMAC, ARDisplayString(m,rr));
+ SendNDP(m, NDP_Adv, NDP_Override, rr, &rr->AddressProxy.ip.v6, &rr->WakeUp.IMAC, &AllHosts_v6, &AllHosts_v6_Eth);
+ #endif
+ }
+ LogSPS("ClearProxyRecords: Removing %3d AC %2d %02X H-MAC %.6a I-MAC %.6a %d %d %s",
+ m->ProxyRecords, rr->AnnounceCount, rr->resrec.RecordType,
+ &rr->WakeUp.HMAC, &rr->WakeUp.IMAC, rr->WakeUp.seq, owner->seq, ARDisplayString(m, rr));
+ if (rr->resrec.RecordType == kDNSRecordTypeDeregistering) rr->resrec.RecordType = kDNSRecordTypeShared;
+ rr->WakeUp.HMAC = zeroEthAddr; // Clear HMAC so that mDNS_Deregister_internal doesn't waste packets trying to wake this host
+ rr->RequireGoodbye = mDNSfalse; // and we don't want to send goodbye for it, since real host is now back and functional
+ mDNS_Deregister_internal(m, rr, mDNS_Dereg_normal);
+ SetSPSProxyListChanged(m->rec.r.resrec.InterfaceID);
+ }
+ // Mustn't advance m->CurrentRecord until *after* mDNS_Deregister_internal, because
+ // new records could have been added to the end of the list as a result of that call.
+ if (m->CurrentRecord == rr) // If m->CurrentRecord was not advanced for us, do it now
+ m->CurrentRecord = rr->next;
+ }
+}
// ProcessQuery examines a received query to see if we have any answers to give
mDNSlocal mDNSu8 *ProcessQuery(mDNS *const m, const DNSMessage *const query, const mDNSu8 *const end,
- const mDNSAddr *srcaddr, const mDNSInterfaceID InterfaceID, mDNSBool LegacyQuery, mDNSBool QueryWasMulticast,
- mDNSBool QueryWasLocalUnicast, DNSMessage *const response)
- {
- mDNSBool FromLocalSubnet = srcaddr && mDNS_AddressIsLocalSubnet(m, InterfaceID, srcaddr);
- AuthRecord *ResponseRecords = mDNSNULL;
- AuthRecord **nrp = &ResponseRecords;
- CacheRecord *ExpectedAnswers = mDNSNULL; // Records in our cache we expect to see updated
- CacheRecord **eap = &ExpectedAnswers;
- DNSQuestion *DupQuestions = mDNSNULL; // Our questions that are identical to questions in this packet
- DNSQuestion **dqp = &DupQuestions;
- mDNSs32 delayresponse = 0;
- mDNSBool SendLegacyResponse = mDNSfalse;
- const mDNSu8 *ptr;
- mDNSu8 *responseptr = mDNSNULL;
- AuthRecord *rr;
- int i;
-
- // ***
- // *** 1. Look in Additional Section for an OPT record
- // ***
- ptr = LocateOptRR(query, end, DNSOpt_OwnerData_ID_Space);
- if (ptr)
- {
- ptr = GetLargeResourceRecord(m, query, ptr, end, InterfaceID, kDNSRecordTypePacketAdd, &m->rec);
- if (ptr && m->rec.r.resrec.RecordType != kDNSRecordTypePacketNegative && m->rec.r.resrec.rrtype == kDNSType_OPT)
- {
- const rdataOPT *opt;
- const rdataOPT *const e = (const rdataOPT *)&m->rec.r.resrec.rdata->u.data[m->rec.r.resrec.rdlength];
- // Find owner sub-option(s). We verify that the MAC is non-zero, otherwise we could inadvertently
- // delete all our own AuthRecords (which are identified by having zero MAC tags on them).
- for (opt = &m->rec.r.resrec.rdata->u.opt[0]; opt < e; opt++)
- if (opt->opt == kDNSOpt_Owner && opt->u.owner.vers == 0 && opt->u.owner.HMAC.l[0])
- {
- ClearProxyRecords(m, &opt->u.owner, m->DuplicateRecords);
- ClearProxyRecords(m, &opt->u.owner, m->ResourceRecords);
- }
- }
- m->rec.r.resrec.RecordType = 0; // Clear RecordType to show we're not still using it
- }
-
- // ***
- // *** 2. Parse Question Section and mark potential answers
- // ***
- ptr = query->data;
- for (i=0; i<query->h.numQuestions; i++) // For each question...
- {
- mDNSBool QuestionNeedsMulticastResponse;
- int NumAnswersForThisQuestion = 0;
- AuthRecord *NSECAnswer = mDNSNULL;
- DNSQuestion pktq, *q;
- ptr = getQuestion(query, ptr, end, InterfaceID, &pktq); // get the question...
- if (!ptr) goto exit;
-
- // The only queries that *need* a multicast response are:
- // * Queries sent via multicast
- // * from port 5353
- // * that don't have the kDNSQClass_UnicastResponse bit set
- // These queries need multicast responses because other clients will:
- // * suppress their own identical questions when they see these questions, and
- // * expire their cache records if they don't see the expected responses
- // For other queries, we may still choose to send the occasional multicast response anyway,
- // to keep our neighbours caches warm, and for ongoing conflict detection.
- QuestionNeedsMulticastResponse = QueryWasMulticast && !LegacyQuery && !(pktq.qclass & kDNSQClass_UnicastResponse);
- // Clear the UnicastResponse flag -- don't want to confuse the rest of the code that follows later
- pktq.qclass &= ~kDNSQClass_UnicastResponse;
-
- // Note: We use the m->CurrentRecord mechanism here because calling ResolveSimultaneousProbe
- // can result in user callbacks which may change the record list and/or question list.
- // Also note: we just mark potential answer records here, without trying to build the
- // "ResponseRecords" list, because we don't want to risk user callbacks deleting records
- // from that list while we're in the middle of trying to build it.
- if (m->CurrentRecord)
- LogMsg("ProcessQuery ERROR m->CurrentRecord already set %s", ARDisplayString(m, m->CurrentRecord));
- m->CurrentRecord = m->ResourceRecords;
- while (m->CurrentRecord)
- {
- rr = m->CurrentRecord;
- m->CurrentRecord = rr->next;
- if (AnyTypeRecordAnswersQuestion(&rr->resrec, &pktq) && (QueryWasMulticast || QueryWasLocalUnicast || rr->AllowRemoteQuery))
- {
- if (RRTypeAnswersQuestionType(&rr->resrec, pktq.qtype))
- {
- if (rr->resrec.RecordType == kDNSRecordTypeUnique)
- ResolveSimultaneousProbe(m, query, end, &pktq, rr);
- else if (ResourceRecordIsValidAnswer(rr))
- {
- NumAnswersForThisQuestion++;
- // Note: We should check here if this is a probe-type query, and if so, generate an immediate
- // unicast answer back to the source, because timeliness in answering probes is important.
-
- // Notes:
- // NR_AnswerTo pointing into query packet means "answer via immediate legacy unicast" (may *also* choose to multicast)
- // NR_AnswerTo == (mDNSu8*)~1 means "answer via delayed unicast" (to modern querier; may promote to multicast instead)
- // NR_AnswerTo == (mDNSu8*)~0 means "definitely answer via multicast" (can't downgrade to unicast later)
- // If we're not multicasting this record because the kDNSQClass_UnicastResponse bit was set,
- // but the multicast querier is not on a matching subnet (e.g. because of overlaid subnets on one link)
- // then we'll multicast it anyway (if we unicast, the receiver will ignore it because it has an apparently non-local source)
- if (QuestionNeedsMulticastResponse || (!FromLocalSubnet && QueryWasMulticast && !LegacyQuery))
- {
- // We only mark this question for sending if it is at least one second since the last time we multicast it
- // on this interface. If it is more than a second, or LastMCInterface is different, then we may multicast it.
- // This is to guard against the case where someone blasts us with queries as fast as they can.
- if (m->timenow - (rr->LastMCTime + mDNSPlatformOneSecond) >= 0 ||
- (rr->LastMCInterface != mDNSInterfaceMark && rr->LastMCInterface != InterfaceID))
- rr->NR_AnswerTo = (mDNSu8*)~0;
- }
- else if (!rr->NR_AnswerTo) rr->NR_AnswerTo = LegacyQuery ? ptr : (mDNSu8*)~1;
- }
- }
- else if ((rr->resrec.RecordType & kDNSRecordTypeActiveUniqueMask) && ResourceRecordIsValidAnswer(rr))
- {
- // If we don't have any answers for this question, but we do own another record with the same name,
- // then we'll want to mark it to generate an NSEC record on this interface
- if (!NSECAnswer) NSECAnswer = rr;
- }
- }
- }
-
- if (NumAnswersForThisQuestion == 0 && NSECAnswer)
- {
- NumAnswersForThisQuestion++;
- NSECAnswer->SendNSECNow = InterfaceID;
- m->NextScheduledResponse = m->timenow;
- }
-
- // If we couldn't answer this question, someone else might be able to,
- // so use random delay on response to reduce collisions
- if (NumAnswersForThisQuestion == 0) delayresponse = mDNSPlatformOneSecond; // Divided by 50 = 20ms
-
+ const mDNSAddr *srcaddr, const mDNSInterfaceID InterfaceID, mDNSBool LegacyQuery, mDNSBool QueryWasMulticast,
+ mDNSBool QueryWasLocalUnicast, DNSMessage *const response)
+{
+ mDNSBool FromLocalSubnet = srcaddr && mDNS_AddressIsLocalSubnet(m, InterfaceID, srcaddr, mDNSNULL);
+ AuthRecord *ResponseRecords = mDNSNULL;
+ AuthRecord **nrp = &ResponseRecords;
+
+#if POOF_ENABLED
+ CacheRecord *ExpectedAnswers = mDNSNULL; // Records in our cache we expect to see updated
+ CacheRecord **eap = &ExpectedAnswers;
+#endif // POOF_ENABLED
+
+ DNSQuestion *DupQuestions = mDNSNULL; // Our questions that are identical to questions in this packet
+ DNSQuestion **dqp = &DupQuestions;
+ mDNSs32 delayresponse = 0;
+ mDNSBool SendLegacyResponse = mDNSfalse;
+ const mDNSu8 *ptr;
+ mDNSu8 *responseptr = mDNSNULL;
+ AuthRecord *rr;
+ int i;
+ CacheRecord *McastNSEC3Records = mDNSNULL;
+
+ // ***
+ // *** 1. Look in Additional Section for an OPT record
+ // ***
+ ptr = LocateOptRR(query, end, DNSOpt_OwnerData_ID_Space);
+ if (ptr)
+ {
+ ptr = GetLargeResourceRecord(m, query, ptr, end, InterfaceID, kDNSRecordTypePacketAdd, &m->rec);
+ if (ptr && m->rec.r.resrec.RecordType != kDNSRecordTypePacketNegative && m->rec.r.resrec.rrtype == kDNSType_OPT)
+ {
+ const rdataOPT *opt;
+ const rdataOPT *const e = (const rdataOPT *)&m->rec.r.resrec.rdata->u.data[m->rec.r.resrec.rdlength];
+ // Find owner sub-option(s). We verify that the MAC is non-zero, otherwise we could inadvertently
+ // delete all our own AuthRecords (which are identified by having zero MAC tags on them).
+ for (opt = &m->rec.r.resrec.rdata->u.opt[0]; opt < e; opt++)
+ if (opt->opt == kDNSOpt_Owner && opt->u.owner.vers == 0 && opt->u.owner.HMAC.l[0])
+ {
+ ClearProxyRecords(m, &opt->u.owner, m->DuplicateRecords);
+ ClearProxyRecords(m, &opt->u.owner, m->ResourceRecords);
+ }
+ }
+ m->rec.r.resrec.RecordType = 0; // Clear RecordType to show we're not still using it
+ }
+
+ //
+ // Look in Authority Section for NSEC3 record
+ //
+
+ mDNSParseNSEC3Records(m, query, end, InterfaceID, &McastNSEC3Records);
+
+ // ***
+ // *** 2. Parse Question Section and mark potential answers
+ // ***
+ ptr = query->data;
+ for (i=0; i<query->h.numQuestions; i++) // For each question...
+ {
+ mDNSBool QuestionNeedsMulticastResponse;
+ int NumAnswersForThisQuestion = 0;
+ AuthRecord *NSECAnswer = mDNSNULL;
+ DNSQuestion pktq, *q;
+ ptr = getQuestion(query, ptr, end, InterfaceID, &pktq); // get the question...
+ if (!ptr) goto exit;
+
+ pktq.AnonInfo = mDNSNULL;
+ if (McastNSEC3Records)
+ InitializeAnonInfoForQuestion(m, &McastNSEC3Records, &pktq);
+ // The only queries that *need* a multicast response are:
+ // * Queries sent via multicast
+ // * from port 5353
+ // * that don't have the kDNSQClass_UnicastResponse bit set
+ // These queries need multicast responses because other clients will:
+ // * suppress their own identical questions when they see these questions, and
+ // * expire their cache records if they don't see the expected responses
+ // For other queries, we may still choose to send the occasional multicast response anyway,
+ // to keep our neighbours caches warm, and for ongoing conflict detection.
+ QuestionNeedsMulticastResponse = QueryWasMulticast && !LegacyQuery && !(pktq.qclass & kDNSQClass_UnicastResponse);
+
+ if (pktq.qclass & kDNSQClass_UnicastResponse)
+ m->mDNSStats.UnicastBitInQueries++;
+ else
+ m->mDNSStats.NormalQueries++;
+
+ // Clear the UnicastResponse flag -- don't want to confuse the rest of the code that follows later
+ pktq.qclass &= ~kDNSQClass_UnicastResponse;
+
+ // Note: We use the m->CurrentRecord mechanism here because calling ResolveSimultaneousProbe
+ // can result in user callbacks which may change the record list and/or question list.
+ // Also note: we just mark potential answer records here, without trying to build the
+ // "ResponseRecords" list, because we don't want to risk user callbacks deleting records
+ // from that list while we're in the middle of trying to build it.
+ if (m->CurrentRecord)
+ LogMsg("ProcessQuery ERROR m->CurrentRecord already set %s", ARDisplayString(m, m->CurrentRecord));
+ m->CurrentRecord = m->ResourceRecords;
+ while (m->CurrentRecord)
+ {
+ rr = m->CurrentRecord;
+ m->CurrentRecord = rr->next;
+ if (AnyTypeRecordAnswersQuestion(&rr->resrec, &pktq) && (QueryWasMulticast || QueryWasLocalUnicast || rr->AllowRemoteQuery))
+ {
+ m->mDNSStats.MatchingAnswersForQueries++;
+ if (RRTypeAnswersQuestionType(&rr->resrec, pktq.qtype))
+ {
+ if (rr->resrec.RecordType == kDNSRecordTypeUnique)
+ ResolveSimultaneousProbe(m, query, end, &pktq, rr);
+ else if (ResourceRecordIsValidAnswer(rr))
+ {
+ NumAnswersForThisQuestion++;
+ // As we have verified this question to be part of the same subset,
+ // set the anonymous data which is needed below when walk the cache
+ // records to see what answers we should be expecting. The cache records
+ // may cache only the nsec3RR and not the anonymous data itself.
+ if (pktq.AnonInfo && rr->resrec.AnonInfo)
+ SetAnonData(&pktq, &rr->resrec, mDNStrue);
+
+ // Note: We should check here if this is a probe-type query, and if so, generate an immediate
+ // unicast answer back to the source, because timeliness in answering probes is important.
+
+ // Notes:
+ // NR_AnswerTo pointing into query packet means "answer via immediate legacy unicast" (may *also* choose to multicast)
+ // NR_AnswerTo == NR_AnswerUnicast means "answer via delayed unicast" (to modern querier; may promote to multicast instead)
+ // NR_AnswerTo == NR_AnswerMulticast means "definitely answer via multicast" (can't downgrade to unicast later)
+ // If we're not multicasting this record because the kDNSQClass_UnicastResponse bit was set,
+ // but the multicast querier is not on a matching subnet (e.g. because of overlaid subnets on one link)
+ // then we'll multicast it anyway (if we unicast, the receiver will ignore it because it has an apparently non-local source)
+ if (QuestionNeedsMulticastResponse || (!FromLocalSubnet && QueryWasMulticast && !LegacyQuery))
+ {
+ // We only mark this question for sending if it is at least one second since the last time we multicast it
+ // on this interface. If it is more than a second, or LastMCInterface is different, then we may multicast it.
+ // This is to guard against the case where someone blasts us with queries as fast as they can.
+ if (m->timenow - (rr->LastMCTime + mDNSPlatformOneSecond) >= 0 ||
+ (rr->LastMCInterface != mDNSInterfaceMark && rr->LastMCInterface != InterfaceID))
+ rr->NR_AnswerTo = NR_AnswerMulticast;
+ }
+ else if (!rr->NR_AnswerTo) rr->NR_AnswerTo = LegacyQuery ? ptr : NR_AnswerUnicast;
+ }
+ }
+ else if ((rr->resrec.RecordType & kDNSRecordTypeActiveUniqueMask) && ResourceRecordIsValidAnswer(rr))
+ {
+ // If we don't have any answers for this question, but we do own another record with the same name,
+ // then we'll want to mark it to generate an NSEC record on this interface
+ if (!NSECAnswer) NSECAnswer = rr;
+ }
+ }
+ }
+
+ if (NumAnswersForThisQuestion == 0 && NSECAnswer)
+ {
+ NumAnswersForThisQuestion++;
+ NSECAnswer->SendNSECNow = InterfaceID;
+ m->NextScheduledResponse = m->timenow;
+ }
+
+ // If we couldn't answer this question, someone else might be able to,
+ // so use random delay on response to reduce collisions
+ if (NumAnswersForThisQuestion == 0) delayresponse = mDNSPlatformOneSecond; // Divided by 50 = 20ms
+
+ if (query->h.flags.b[0] & kDNSFlag0_TC)
+ m->mDNSStats.KnownAnswerMultiplePkts++;
#if ENABLE_MULTI_PACKET_QUERY_SNOOPING
- if (QuestionNeedsMulticastResponse)
+ if (QuestionNeedsMulticastResponse)
#else
- // We only do the following accelerated cache expiration and duplicate question suppression processing
- // for non-truncated multicast queries with multicast responses.
- // For any query generating a unicast response we don't do this because we can't assume we will see the response.
- // For truncated queries we don't do this because a response we're expecting might be suppressed by a subsequent
- // known-answer packet, and when there's packet loss we can't safely assume we'll receive *all* known-answer packets.
- if (QuestionNeedsMulticastResponse && !(query->h.flags.b[0] & kDNSFlag0_TC))
+ // We only do the following accelerated cache expiration and duplicate question suppression processing
+ // for non-truncated multicast queries with multicast responses.
+ // For any query generating a unicast response we don't do this because we can't assume we will see the response.
+ // For truncated queries we don't do this because a response we're expecting might be suppressed by a subsequent
+ // known-answer packet, and when there's packet loss we can't safely assume we'll receive *all* known-answer packets.
+ if (QuestionNeedsMulticastResponse && !(query->h.flags.b[0] & kDNSFlag0_TC))
#endif
- {
- const mDNSu32 slot = HashSlot(&pktq.qname);
- CacheGroup *cg = CacheGroupForName(m, slot, pktq.qnamehash, &pktq.qname);
- CacheRecord *cr;
-
- // Make a list indicating which of our own cache records we expect to see updated as a result of this query
- // Note: Records larger than 1K are not habitually multicast, so don't expect those to be updated
+ {
+#if POOF_ENABLED
+ const mDNSu32 slot = HashSlot(&pktq.qname);
+ CacheGroup *cg = CacheGroupForName(m, slot, pktq.qnamehash, &pktq.qname);
+ CacheRecord *cr;
+
+ // Make a list indicating which of our own cache records we expect to see updated as a result of this query
+ // Note: Records larger than 1K are not habitually multicast, so don't expect those to be updated
#if ENABLE_MULTI_PACKET_QUERY_SNOOPING
- if (!(query->h.flags.b[0] & kDNSFlag0_TC))
-#endif
- for (cr = cg ? cg->members : mDNSNULL; cr; cr=cr->next)
- if (SameNameRecordAnswersQuestion(&cr->resrec, &pktq) && cr->resrec.rdlength <= SmallRecordLimit)
- if (!cr->NextInKAList && eap != &cr->NextInKAList)
- {
- *eap = cr;
- eap = &cr->NextInKAList;
+ if (!(query->h.flags.b[0] & kDNSFlag0_TC))
+#endif // ENABLE_MULTI_PACKET_QUERY_SNOOPING
+ for (cr = cg ? cg->members : mDNSNULL; cr; cr=cr->next)
+ if (SameNameRecordAnswersQuestion(&cr->resrec, &pktq) && cr->resrec.rdlength <= SmallRecordLimit)
+ if (!cr->NextInKAList && eap != &cr->NextInKAList)
+ {
+ *eap = cr;
+ eap = &cr->NextInKAList;
#if ENABLE_MULTI_PACKET_QUERY_SNOOPING
- if (cr->MPUnansweredQ == 0 || m->timenow - cr->MPLastUnansweredQT >= mDNSPlatformOneSecond)
- {
- // Although MPUnansweredQ is only really used for multi-packet query processing,
- // we increment it for both single-packet and multi-packet queries, so that it stays in sync
- // with the MPUnansweredKA value, which by necessity is incremented for both query types.
- cr->MPUnansweredQ++;
- cr->MPLastUnansweredQT = m->timenow;
- cr->MPExpectingKA = mDNStrue;
- }
-#endif
- }
-
- // Check if this question is the same as any of mine.
- // We only do this for non-truncated queries. Right now it would be too complicated to try
- // to keep track of duplicate suppression state between multiple packets, especially when we
- // can't guarantee to receive all of the Known Answer packets that go with a particular query.
+ if (cr->MPUnansweredQ == 0 || m->timenow - cr->MPLastUnansweredQT >= mDNSPlatformOneSecond)
+ {
+ // Although MPUnansweredQ is only really used for multi-packet query processing,
+ // we increment it for both single-packet and multi-packet queries, so that it stays in sync
+ // with the MPUnansweredKA value, which by necessity is incremented for both query types.
+ cr->MPUnansweredQ++;
+ cr->MPLastUnansweredQT = m->timenow;
+ cr->MPExpectingKA = mDNStrue;
+ }
+#endif // ENABLE_MULTI_PACKET_QUERY_SNOOPING
+ }
+#endif // POOF_ENABLED
+
+ // Check if this question is the same as any of mine.
+ // We only do this for non-truncated queries. Right now it would be too complicated to try
+ // to keep track of duplicate suppression state between multiple packets, especially when we
+ // can't guarantee to receive all of the Known Answer packets that go with a particular query.
#if ENABLE_MULTI_PACKET_QUERY_SNOOPING
- if (!(query->h.flags.b[0] & kDNSFlag0_TC))
+ if (!(query->h.flags.b[0] & kDNSFlag0_TC))
#endif
- for (q = m->Questions; q; q=q->next)
- if (!q->Target.type && ActiveQuestion(q) && m->timenow - q->LastQTxTime > mDNSPlatformOneSecond / 4)
- if (!q->InterfaceID || q->InterfaceID == InterfaceID)
- if (q->NextInDQList == mDNSNULL && dqp != &q->NextInDQList)
- if (q->qtype == pktq.qtype &&
- q->qclass == pktq.qclass &&
- q->qnamehash == pktq.qnamehash && SameDomainName(&q->qname, &pktq.qname))
- { *dqp = q; dqp = &q->NextInDQList; }
- }
- }
-
- // ***
- // *** 3. Now we can safely build the list of marked answers
- // ***
- for (rr = m->ResourceRecords; rr; rr=rr->next) // Now build our list of potential answers
- if (rr->NR_AnswerTo) // If we marked the record...
- AddRecordToResponseList(&nrp, rr, mDNSNULL); // ... add it to the list
-
- // ***
- // *** 4. Add additional records
- // ***
- AddAdditionalsToResponseList(m, ResponseRecords, &nrp, InterfaceID);
-
- // ***
- // *** 5. Parse Answer Section and cancel any records disallowed by Known-Answer list
- // ***
- for (i=0; i<query->h.numAnswers; i++) // For each record in the query's answer section...
- {
- // Get the record...
- CacheRecord *ourcacherr;
- ptr = GetLargeResourceRecord(m, query, ptr, end, InterfaceID, kDNSRecordTypePacketAns, &m->rec);
- if (!ptr) goto exit;
- if (m->rec.r.resrec.RecordType != kDNSRecordTypePacketNegative)
- {
- // See if this Known-Answer suppresses any of our currently planned answers
- for (rr=ResponseRecords; rr; rr=rr->NextResponse)
- if (MustSendRecord(rr) && ShouldSuppressKnownAnswer(&m->rec.r, rr))
- { rr->NR_AnswerTo = mDNSNULL; rr->NR_AdditionalTo = mDNSNULL; }
-
- // See if this Known-Answer suppresses any previously scheduled answers (for multi-packet KA suppression)
- for (rr=m->ResourceRecords; rr; rr=rr->next)
- {
- // If we're planning to send this answer on this interface, and only on this interface, then allow KA suppression
- if (rr->ImmedAnswer == InterfaceID && ShouldSuppressKnownAnswer(&m->rec.r, rr))
- {
- if (srcaddr->type == mDNSAddrType_IPv4)
- {
- if (mDNSSameIPv4Address(rr->v4Requester, srcaddr->ip.v4)) rr->v4Requester = zerov4Addr;
- }
- else if (srcaddr->type == mDNSAddrType_IPv6)
- {
- if (mDNSSameIPv6Address(rr->v6Requester, srcaddr->ip.v6)) rr->v6Requester = zerov6Addr;
- }
- if (mDNSIPv4AddressIsZero(rr->v4Requester) && mDNSIPv6AddressIsZero(rr->v6Requester))
- {
- rr->ImmedAnswer = mDNSNULL;
- rr->ImmedUnicast = mDNSfalse;
- #if MDNS_LOG_ANSWER_SUPPRESSION_TIMES
- LogMsg("Suppressed after%4d: %s", m->timenow - rr->ImmedAnswerMarkTime, ARDisplayString(m, rr));
- #endif
- }
- }
- }
-
- ourcacherr = FindIdenticalRecordInCache(m, &m->rec.r.resrec);
-
- #if ENABLE_MULTI_PACKET_QUERY_SNOOPING
- // See if this Known-Answer suppresses any answers we were expecting for our cache records. We do this always,
- // even if the TC bit is not set (the TC bit will *not* be set in the *last* packet of a multi-packet KA list).
- if (ourcacherr && ourcacherr->MPExpectingKA && m->timenow - ourcacherr->MPLastUnansweredQT < mDNSPlatformOneSecond)
- {
- ourcacherr->MPUnansweredKA++;
- ourcacherr->MPExpectingKA = mDNSfalse;
- }
- #endif
-
- // Having built our ExpectedAnswers list from the questions in this packet, we then remove
- // any records that are suppressed by the Known Answer list in this packet.
- eap = &ExpectedAnswers;
- while (*eap)
- {
- CacheRecord *cr = *eap;
- if (cr->resrec.InterfaceID == InterfaceID && IdenticalResourceRecord(&m->rec.r.resrec, &cr->resrec))
- { *eap = cr->NextInKAList; cr->NextInKAList = mDNSNULL; }
- else eap = &cr->NextInKAList;
- }
-
- // See if this Known-Answer is a surprise to us. If so, we shouldn't suppress our own query.
- if (!ourcacherr)
- {
- dqp = &DupQuestions;
- while (*dqp)
- {
- DNSQuestion *q = *dqp;
- if (ResourceRecordAnswersQuestion(&m->rec.r.resrec, q))
- { *dqp = q->NextInDQList; q->NextInDQList = mDNSNULL; }
- else dqp = &q->NextInDQList;
- }
- }
- }
- m->rec.r.resrec.RecordType = 0; // Clear RecordType to show we're not still using it
- }
-
- // ***
- // *** 6. Cancel any additionals that were added because of now-deleted records
- // ***
- for (rr=ResponseRecords; rr; rr=rr->NextResponse)
- if (rr->NR_AdditionalTo && !MustSendRecord(rr->NR_AdditionalTo))
- { rr->NR_AnswerTo = mDNSNULL; rr->NR_AdditionalTo = mDNSNULL; }
-
- // ***
- // *** 7. Mark the send flags on the records we plan to send
- // ***
- for (rr=ResponseRecords; rr; rr=rr->NextResponse)
- {
- if (rr->NR_AnswerTo)
- {
- mDNSBool SendMulticastResponse = mDNSfalse; // Send modern multicast response
- mDNSBool SendUnicastResponse = mDNSfalse; // Send modern unicast response (not legacy unicast response)
-
- // If it's been a while since we multicast this, then send a multicast response for conflict detection, etc.
- if (m->timenow - (rr->LastMCTime + TicksTTL(rr)/4) >= 0)
- {
- SendMulticastResponse = mDNStrue;
- // If this record was marked for modern (delayed) unicast response, then mark it as promoted to
- // multicast response instead (don't want to end up ALSO setting SendUnicastResponse in the check below).
- // If this record was marked for legacy unicast response, then we mustn't change the NR_AnswerTo value.
- if (rr->NR_AnswerTo == (mDNSu8*)~1) rr->NR_AnswerTo = (mDNSu8*)~0;
- }
-
- // If the client insists on a multicast response, then we'd better send one
- if (rr->NR_AnswerTo == (mDNSu8*)~0) SendMulticastResponse = mDNStrue;
- else if (rr->NR_AnswerTo == (mDNSu8*)~1) SendUnicastResponse = mDNStrue;
- else if (rr->NR_AnswerTo) SendLegacyResponse = mDNStrue;
-
- if (SendMulticastResponse || SendUnicastResponse)
- {
+ // For anonymous question, the duplicate suppressesion should happen if the
+ // question belongs in the same group. As the group is expected to be
+ // small, we don't do the optimization for now.
+ if (!pktq.AnonInfo)
+ {
+ for (q = m->Questions; q; q=q->next)
+ if (!q->Target.type && ActiveQuestion(q) && m->timenow - q->LastQTxTime > mDNSPlatformOneSecond / 4)
+ if (!q->InterfaceID || q->InterfaceID == InterfaceID)
+ if (q->NextInDQList == mDNSNULL && dqp != &q->NextInDQList)
+ if (q->qtype == pktq.qtype &&
+ q->qclass == pktq.qclass &&
+ q->qnamehash == pktq.qnamehash && SameDomainName(&q->qname, &pktq.qname))
+ { *dqp = q; dqp = &q->NextInDQList; }
+ }
+ }
+ if (pktq.AnonInfo)
+ {
+ FreeAnonInfo(pktq.AnonInfo);
+ }
+ }
+
+ // ***
+ // *** 3. Now we can safely build the list of marked answers
+ // ***
+ for (rr = m->ResourceRecords; rr; rr=rr->next) // Now build our list of potential answers
+ if (rr->NR_AnswerTo) // If we marked the record...
+ AddRecordToResponseList(&nrp, rr, mDNSNULL); // ... add it to the list
+
+ // ***
+ // *** 4. Add additional records
+ // ***
+ AddAdditionalsToResponseList(m, ResponseRecords, &nrp, InterfaceID);
+
+ // ***
+ // *** 5. Parse Answer Section and cancel any records disallowed by Known-Answer list
+ // ***
+ for (i=0; i<query->h.numAnswers; i++) // For each record in the query's answer section...
+ {
+ // Get the record...
+ CacheRecord *ourcacherr;
+ ptr = GetLargeResourceRecord(m, query, ptr, end, InterfaceID, kDNSRecordTypePacketAns, &m->rec);
+ if (!ptr) goto exit;
+ if (m->rec.r.resrec.RecordType != kDNSRecordTypePacketNegative)
+ {
+ // See if this Known-Answer suppresses any of our currently planned answers
+ for (rr=ResponseRecords; rr; rr=rr->NextResponse)
+ {
+ if (MustSendRecord(rr) && ShouldSuppressKnownAnswer(&m->rec.r, rr))
+ {
+ m->mDNSStats.KnownAnswerSuppressions++;
+ rr->NR_AnswerTo = mDNSNULL;
+ rr->NR_AdditionalTo = mDNSNULL;
+ }
+ }
+
+ // See if this Known-Answer suppresses any previously scheduled answers (for multi-packet KA suppression)
+ for (rr=m->ResourceRecords; rr; rr=rr->next)
+ {
+ // If we're planning to send this answer on this interface, and only on this interface, then allow KA suppression
+ if (rr->ImmedAnswer == InterfaceID && ShouldSuppressKnownAnswer(&m->rec.r, rr))
+ {
+ if (srcaddr->type == mDNSAddrType_IPv4)
+ {
+ if (mDNSSameIPv4Address(rr->v4Requester, srcaddr->ip.v4)) rr->v4Requester = zerov4Addr;
+ }
+ else if (srcaddr->type == mDNSAddrType_IPv6)
+ {
+ if (mDNSSameIPv6Address(rr->v6Requester, srcaddr->ip.v6)) rr->v6Requester = zerov6Addr;
+ }
+ if (mDNSIPv4AddressIsZero(rr->v4Requester) && mDNSIPv6AddressIsZero(rr->v6Requester))
+ {
+ m->mDNSStats.KnownAnswerSuppressions++;
+ rr->ImmedAnswer = mDNSNULL;
+ rr->ImmedUnicast = mDNSfalse;
+ #if MDNS_LOG_ANSWER_SUPPRESSION_TIMES
+ LogMsg("Suppressed after%4d: %s", m->timenow - rr->ImmedAnswerMarkTime, ARDisplayString(m, rr));
+ #endif
+ }
+ }
+ }
+
+ ourcacherr = FindIdenticalRecordInCache(m, &m->rec.r.resrec);
+
+ #if ENABLE_MULTI_PACKET_QUERY_SNOOPING
+ // See if this Known-Answer suppresses any answers we were expecting for our cache records. We do this always,
+ // even if the TC bit is not set (the TC bit will *not* be set in the *last* packet of a multi-packet KA list).
+ if (ourcacherr && ourcacherr->MPExpectingKA && m->timenow - ourcacherr->MPLastUnansweredQT < mDNSPlatformOneSecond)
+ {
+ ourcacherr->MPUnansweredKA++;
+ ourcacherr->MPExpectingKA = mDNSfalse;
+ }
+ #endif
+
+#if POOF_ENABLED
+ // Having built our ExpectedAnswers list from the questions in this packet, we then remove
+ // any records that are suppressed by the Known Answer list in this packet.
+ eap = &ExpectedAnswers;
+ while (*eap)
+ {
+ CacheRecord *cr = *eap;
+ if (cr->resrec.InterfaceID == InterfaceID && IdenticalResourceRecord(&m->rec.r.resrec, &cr->resrec))
+ { *eap = cr->NextInKAList; cr->NextInKAList = mDNSNULL; }
+ else eap = &cr->NextInKAList;
+ }
+#endif // POOF_ENABLED
+
+ // See if this Known-Answer is a surprise to us. If so, we shouldn't suppress our own query.
+ if (!ourcacherr)
+ {
+ dqp = &DupQuestions;
+ while (*dqp)
+ {
+ DNSQuestion *q = *dqp;
+ if (ResourceRecordAnswersQuestion(&m->rec.r.resrec, q))
+ { *dqp = q->NextInDQList; q->NextInDQList = mDNSNULL; }
+ else dqp = &q->NextInDQList;
+ }
+ }
+ }
+ m->rec.r.resrec.RecordType = 0; // Clear RecordType to show we're not still using it
+ }
+
+ // ***
+ // *** 6. Cancel any additionals that were added because of now-deleted records
+ // ***
+ for (rr=ResponseRecords; rr; rr=rr->NextResponse)
+ if (rr->NR_AdditionalTo && !MustSendRecord(rr->NR_AdditionalTo))
+ { rr->NR_AnswerTo = mDNSNULL; rr->NR_AdditionalTo = mDNSNULL; }
+
+ // ***
+ // *** 7. Mark the send flags on the records we plan to send
+ // ***
+ for (rr=ResponseRecords; rr; rr=rr->NextResponse)
+ {
+ if (rr->NR_AnswerTo)
+ {
+ mDNSBool SendMulticastResponse = mDNSfalse; // Send modern multicast response
+ mDNSBool SendUnicastResponse = mDNSfalse; // Send modern unicast response (not legacy unicast response)
+
+#if !TARGET_OS_EMBEDDED
+ // always honor kDNSQClass_UnicastResponse in embedded environment to increase reliability
+ // in high multicast packet loss environments.
+
+ // If it's been one TTL/4 since we multicast this, then send a multicast response
+ // for conflict detection, etc.
+ if (m->timenow - (rr->LastMCTime + TicksTTL(rr)/4) >= 0)
+ {
+ SendMulticastResponse = mDNStrue;
+ // If this record was marked for modern (delayed) unicast response, then mark it as promoted to
+ // multicast response instead (don't want to end up ALSO setting SendUnicastResponse in the check below).
+ // If this record was marked for legacy unicast response, then we mustn't change the NR_AnswerTo value.
+ if (rr->NR_AnswerTo == NR_AnswerUnicast)
+ {
+ m->mDNSStats.UnicastDemotedToMulticast++;
+ rr->NR_AnswerTo = NR_AnswerMulticast;
+ }
+ }
+#endif // !TARGET_OS_EMBEDDED
+
+ // If the client insists on a multicast response, then we'd better send one
+ if (rr->NR_AnswerTo == NR_AnswerMulticast)
+ {
+ m->mDNSStats.MulticastResponses++;
+ SendMulticastResponse = mDNStrue;
+ }
+ else if (rr->NR_AnswerTo == NR_AnswerUnicast)
+ {
+ m->mDNSStats.UnicastResponses++;
+ SendUnicastResponse = mDNStrue;
+ }
+ else if (rr->NR_AnswerTo)
+ {
+ SendLegacyResponse = mDNStrue;
+ }
+
+
+ if (SendMulticastResponse || SendUnicastResponse)
+ {
#if MDNS_LOG_ANSWER_SUPPRESSION_TIMES
- rr->ImmedAnswerMarkTime = m->timenow;
+ rr->ImmedAnswerMarkTime = m->timenow;
#endif
- m->NextScheduledResponse = m->timenow;
- // If we're already planning to send this on another interface, just send it on all interfaces
- if (rr->ImmedAnswer && rr->ImmedAnswer != InterfaceID)
- rr->ImmedAnswer = mDNSInterfaceMark;
- else
- {
- rr->ImmedAnswer = InterfaceID; // Record interface to send it on
- if (SendUnicastResponse) rr->ImmedUnicast = mDNStrue;
- if (srcaddr->type == mDNSAddrType_IPv4)
- {
- if (mDNSIPv4AddressIsZero(rr->v4Requester)) rr->v4Requester = srcaddr->ip.v4;
- else if (!mDNSSameIPv4Address(rr->v4Requester, srcaddr->ip.v4)) rr->v4Requester = onesIPv4Addr;
- }
- else if (srcaddr->type == mDNSAddrType_IPv6)
- {
- if (mDNSIPv6AddressIsZero(rr->v6Requester)) rr->v6Requester = srcaddr->ip.v6;
- else if (!mDNSSameIPv6Address(rr->v6Requester, srcaddr->ip.v6)) rr->v6Requester = onesIPv6Addr;
- }
- }
- }
- // If TC flag is set, it means we should expect that additional known answers may be coming in another packet,
- // so we allow roughly half a second before deciding to reply (we've observed inter-packet delays of 100-200ms on 802.11)
- // else, if record is a shared one, spread responses over 100ms to avoid implosion of simultaneous responses
- // else, for a simple unique record reply, we can reply immediately; no need for delay
- if (query->h.flags.b[0] & kDNSFlag0_TC) delayresponse = mDNSPlatformOneSecond * 20; // Divided by 50 = 400ms
- else if (rr->resrec.RecordType == kDNSRecordTypeShared) delayresponse = mDNSPlatformOneSecond; // Divided by 50 = 20ms
- }
- else if (rr->NR_AdditionalTo && rr->NR_AdditionalTo->NR_AnswerTo == (mDNSu8*)~0)
- {
- // Since additional records are an optimization anyway, we only ever send them on one interface at a time
- // If two clients on different interfaces do queries that invoke the same optional additional answer,
- // then the earlier client is out of luck
- rr->ImmedAdditional = InterfaceID;
- // No need to set m->NextScheduledResponse here
- // We'll send these additional records when we send them, or not, as the case may be
- }
- }
-
- // ***
- // *** 8. If we think other machines are likely to answer these questions, set our packet suppression timer
- // ***
- if (delayresponse && (!m->SuppressSending || (m->SuppressSending - m->timenow) < (delayresponse + 49) / 50))
- {
+ m->NextScheduledResponse = m->timenow;
+ // If we're already planning to send this on another interface, just send it on all interfaces
+ if (rr->ImmedAnswer && rr->ImmedAnswer != InterfaceID)
+ rr->ImmedAnswer = mDNSInterfaceMark;
+ else
+ {
+ rr->ImmedAnswer = InterfaceID; // Record interface to send it on
+ if (SendUnicastResponse) rr->ImmedUnicast = mDNStrue;
+ if (srcaddr->type == mDNSAddrType_IPv4)
+ {
+ if (mDNSIPv4AddressIsZero(rr->v4Requester)) rr->v4Requester = srcaddr->ip.v4;
+ else if (!mDNSSameIPv4Address(rr->v4Requester, srcaddr->ip.v4)) rr->v4Requester = onesIPv4Addr;
+ }
+ else if (srcaddr->type == mDNSAddrType_IPv6)
+ {
+ if (mDNSIPv6AddressIsZero(rr->v6Requester)) rr->v6Requester = srcaddr->ip.v6;
+ else if (!mDNSSameIPv6Address(rr->v6Requester, srcaddr->ip.v6)) rr->v6Requester = onesIPv6Addr;
+ }
+ }
+ }
+ // If TC flag is set, it means we should expect that additional known answers may be coming in another packet,
+ // so we allow roughly half a second before deciding to reply (we've observed inter-packet delays of 100-200ms on 802.11)
+ // else, if record is a shared one, spread responses over 100ms to avoid implosion of simultaneous responses
+ // else, for a simple unique record reply, we can reply immediately; no need for delay
+ if (query->h.flags.b[0] & kDNSFlag0_TC) delayresponse = mDNSPlatformOneSecond * 20; // Divided by 50 = 400ms
+ else if (rr->resrec.RecordType == kDNSRecordTypeShared) delayresponse = mDNSPlatformOneSecond; // Divided by 50 = 20ms
+ }
+ else if (rr->NR_AdditionalTo && rr->NR_AdditionalTo->NR_AnswerTo == NR_AnswerMulticast)
+ {
+ // Since additional records are an optimization anyway, we only ever send them on one interface at a time
+ // If two clients on different interfaces do queries that invoke the same optional additional answer,
+ // then the earlier client is out of luck
+ rr->ImmedAdditional = InterfaceID;
+ // No need to set m->NextScheduledResponse here
+ // We'll send these additional records when we send them, or not, as the case may be
+ }
+ }
+
+ // ***
+ // *** 8. If we think other machines are likely to answer these questions, set our packet suppression timer
+ // ***
+ if (delayresponse && (!m->SuppressSending || (m->SuppressSending - m->timenow) < (delayresponse + 49) / 50))
+ {
#if MDNS_LOG_ANSWER_SUPPRESSION_TIMES
- mDNSs32 oldss = m->SuppressSending;
- if (oldss && delayresponse)
- LogMsg("Current SuppressSending delay%5ld; require%5ld", m->SuppressSending - m->timenow, (delayresponse + 49) / 50);
+ mDNSs32 oldss = m->SuppressSending;
+ if (oldss && delayresponse)
+ LogMsg("Current SuppressSending delay%5ld; require%5ld", m->SuppressSending - m->timenow, (delayresponse + 49) / 50);
#endif
- // Pick a random delay:
- // We start with the base delay chosen above (typically either 1 second or 20 seconds),
- // and add a random value in the range 0-5 seconds (making 1-6 seconds or 20-25 seconds).
- // This is an integer value, with resolution determined by the platform clock rate.
- // We then divide that by 50 to get the delay value in ticks. We defer the division until last
- // to get better results on platforms with coarse clock granularity (e.g. ten ticks per second).
- // The +49 before dividing is to ensure we round up, not down, to ensure that even
- // on platforms where the native clock rate is less than fifty ticks per second,
- // we still guarantee that the final calculated delay is at least one platform tick.
- // We want to make sure we don't ever allow the delay to be zero ticks,
- // because if that happens we'll fail the Bonjour Conformance Test.
- // Our final computed delay is 20-120ms for normal delayed replies,
- // or 400-500ms in the case of multi-packet known-answer lists.
- m->SuppressSending = m->timenow + (delayresponse + (mDNSs32)mDNSRandom((mDNSu32)mDNSPlatformOneSecond*5) + 49) / 50;
- if (m->SuppressSending == 0) m->SuppressSending = 1;
+ // Pick a random delay:
+ // We start with the base delay chosen above (typically either 1 second or 20 seconds),
+ // and add a random value in the range 0-5 seconds (making 1-6 seconds or 20-25 seconds).
+ // This is an integer value, with resolution determined by the platform clock rate.
+ // We then divide that by 50 to get the delay value in ticks. We defer the division until last
+ // to get better results on platforms with coarse clock granularity (e.g. ten ticks per second).
+ // The +49 before dividing is to ensure we round up, not down, to ensure that even
+ // on platforms where the native clock rate is less than fifty ticks per second,
+ // we still guarantee that the final calculated delay is at least one platform tick.
+ // We want to make sure we don't ever allow the delay to be zero ticks,
+ // because if that happens we'll fail the Bonjour Conformance Test.
+ // Our final computed delay is 20-120ms for normal delayed replies,
+ // or 400-500ms in the case of multi-packet known-answer lists.
+ m->SuppressSending = m->timenow + (delayresponse + (mDNSs32)mDNSRandom((mDNSu32)mDNSPlatformOneSecond*5) + 49) / 50;
+ if (m->SuppressSending == 0) m->SuppressSending = 1;
#if MDNS_LOG_ANSWER_SUPPRESSION_TIMES
- if (oldss && delayresponse)
- LogMsg("Set SuppressSending to %5ld", m->SuppressSending - m->timenow);
+ if (oldss && delayresponse)
+ LogMsg("Set SuppressSending to %5ld", m->SuppressSending - m->timenow);
#endif
- }
+ }
- // ***
- // *** 9. If query is from a legacy client, or from a new client requesting a unicast reply, then generate a unicast response too
- // ***
- if (SendLegacyResponse)
- responseptr = GenerateUnicastResponse(query, end, InterfaceID, LegacyQuery, response, ResponseRecords);
+ // ***
+ // *** 9. If query is from a legacy client, or from a new client requesting a unicast reply, then generate a unicast response too
+ // ***
+ if (SendLegacyResponse)
+ responseptr = GenerateUnicastResponse(query, end, InterfaceID, LegacyQuery, response, ResponseRecords);
exit:
- m->rec.r.resrec.RecordType = 0; // Clear RecordType to show we're not still using it
-
- // ***
- // *** 10. Finally, clear our link chains ready for use next time
- // ***
- while (ResponseRecords)
- {
- rr = ResponseRecords;
- ResponseRecords = rr->NextResponse;
- rr->NextResponse = mDNSNULL;
- rr->NR_AnswerTo = mDNSNULL;
- rr->NR_AdditionalTo = mDNSNULL;
- }
-
- while (ExpectedAnswers)
- {
- CacheRecord *cr = ExpectedAnswers;
- ExpectedAnswers = cr->NextInKAList;
- cr->NextInKAList = mDNSNULL;
-
- // For non-truncated queries, we can definitively say that we should expect
- // to be seeing a response for any records still left in the ExpectedAnswers list
- if (!(query->h.flags.b[0] & kDNSFlag0_TC))
- if (cr->UnansweredQueries == 0 || m->timenow - cr->LastUnansweredTime >= mDNSPlatformOneSecond)
- {
- cr->UnansweredQueries++;
- cr->LastUnansweredTime = m->timenow;
-#if ENABLE_MULTI_PACKET_QUERY_SNOOPING
- if (cr->UnansweredQueries > 1)
- debugf("ProcessQuery: (!TC) UAQ %lu MPQ %lu MPKA %lu %s",
- cr->UnansweredQueries, cr->MPUnansweredQ, cr->MPUnansweredKA, CRDisplayString(m, cr));
-#endif
- SetNextCacheCheckTimeForRecord(m, cr);
- }
+ m->rec.r.resrec.RecordType = 0; // Clear RecordType to show we're not still using it
- // If we've seen multiple unanswered queries for this record,
- // then mark it to expire in five seconds if we don't get a response by then.
- if (cr->UnansweredQueries >= MaxUnansweredQueries)
- {
+ // ***
+ // *** 10. Finally, clear our link chains ready for use next time
+ // ***
+ while (ResponseRecords)
+ {
+ rr = ResponseRecords;
+ ResponseRecords = rr->NextResponse;
+ rr->NextResponse = mDNSNULL;
+ rr->NR_AnswerTo = mDNSNULL;
+ rr->NR_AdditionalTo = mDNSNULL;
+ }
+
+#if POOF_ENABLED
+ while (ExpectedAnswers)
+ {
+ CacheRecord *cr = ExpectedAnswers;
+ ExpectedAnswers = cr->NextInKAList;
+ cr->NextInKAList = mDNSNULL;
+
+ // For non-truncated queries, we can definitively say that we should expect
+ // to be seeing a response for any records still left in the ExpectedAnswers list
+ if (!(query->h.flags.b[0] & kDNSFlag0_TC))
+ if (cr->UnansweredQueries == 0 || m->timenow - cr->LastUnansweredTime >= mDNSPlatformOneSecond)
+ {
+ cr->UnansweredQueries++;
+ cr->LastUnansweredTime = m->timenow;
#if ENABLE_MULTI_PACKET_QUERY_SNOOPING
- // Only show debugging message if this record was not about to expire anyway
- if (RRExpireTime(cr) - m->timenow > 4 * mDNSPlatformOneSecond)
- debugf("ProcessQuery: (Max) UAQ %lu MPQ %lu MPKA %lu mDNS_Reconfirm() for %s",
- cr->UnansweredQueries, cr->MPUnansweredQ, cr->MPUnansweredKA, CRDisplayString(m, cr));
-#endif
- mDNS_Reconfirm_internal(m, cr, kDefaultReconfirmTimeForNoAnswer);
- }
+ if (cr->UnansweredQueries > 1)
+ debugf("ProcessQuery: (!TC) UAQ %lu MPQ %lu MPKA %lu %s",
+ cr->UnansweredQueries, cr->MPUnansweredQ, cr->MPUnansweredKA, CRDisplayString(m, cr));
+#endif // ENABLE_MULTI_PACKET_QUERY_SNOOPING
+ SetNextCacheCheckTimeForRecord(m, cr);
+ }
+
+ // If we've seen multiple unanswered queries for this record,
+ // then mark it to expire in five seconds if we don't get a response by then.
+ if (cr->UnansweredQueries >= MaxUnansweredQueries)
+ {
#if ENABLE_MULTI_PACKET_QUERY_SNOOPING
- // Make a guess, based on the multi-packet query / known answer counts, whether we think we
- // should have seen an answer for this. (We multiply MPQ by 4 and MPKA by 5, to allow for
- // possible packet loss of up to 20% of the additional KA packets.)
- else if (cr->MPUnansweredQ * 4 > cr->MPUnansweredKA * 5 + 8)
- {
- // We want to do this conservatively.
- // If there are so many machines on the network that they have to use multi-packet known-answer lists,
- // then we don't want them to all hit the network simultaneously with their final expiration queries.
- // By setting the record to expire in four minutes, we achieve two things:
- // (a) the 90-95% final expiration queries will be less bunched together
- // (b) we allow some time for us to witness enough other failed queries that we don't have to do our own
- mDNSu32 remain = (mDNSu32)(RRExpireTime(cr) - m->timenow) / 4;
- if (remain > 240 * (mDNSu32)mDNSPlatformOneSecond)
- remain = 240 * (mDNSu32)mDNSPlatformOneSecond;
-
- // Only show debugging message if this record was not about to expire anyway
- if (RRExpireTime(cr) - m->timenow > 4 * mDNSPlatformOneSecond)
- debugf("ProcessQuery: (MPQ) UAQ %lu MPQ %lu MPKA %lu mDNS_Reconfirm() for %s",
- cr->UnansweredQueries, cr->MPUnansweredQ, cr->MPUnansweredKA, CRDisplayString(m, cr));
-
- if (remain <= 60 * (mDNSu32)mDNSPlatformOneSecond)
- cr->UnansweredQueries++; // Treat this as equivalent to one definite unanswered query
- cr->MPUnansweredQ = 0; // Clear MPQ/MPKA statistics
- cr->MPUnansweredKA = 0;
- cr->MPExpectingKA = mDNSfalse;
-
- if (remain < kDefaultReconfirmTimeForNoAnswer)
- remain = kDefaultReconfirmTimeForNoAnswer;
- mDNS_Reconfirm_internal(m, cr, remain);
- }
-#endif
- }
-
- while (DupQuestions)
- {
- DNSQuestion *q = DupQuestions;
- DupQuestions = q->NextInDQList;
- q->NextInDQList = mDNSNULL;
- i = RecordDupSuppressInfo(q->DupSuppress, m->timenow, InterfaceID, srcaddr->type);
- debugf("ProcessQuery: Recorded DSI for %##s (%s) on %p/%s %d", q->qname.c, DNSTypeName(q->qtype), InterfaceID,
- srcaddr->type == mDNSAddrType_IPv4 ? "v4" : "v6", i);
- }
-
- return(responseptr);
- }
+ // Only show debugging message if this record was not about to expire anyway
+ if (RRExpireTime(cr) - m->timenow > 4 * mDNSPlatformOneSecond)
+ debugf("ProcessQuery: (Max) UAQ %lu MPQ %lu MPKA %lu mDNS_Reconfirm() for %s",
+ cr->UnansweredQueries, cr->MPUnansweredQ, cr->MPUnansweredKA, CRDisplayString(m, cr));
+#endif // ENABLE_MULTI_PACKET_QUERY_SNOOPING
+ m->mDNSStats.PoofCacheDeletions++;
+ mDNS_Reconfirm_internal(m, cr, kDefaultReconfirmTimeForNoAnswer);
+ }
+#if ENABLE_MULTI_PACKET_QUERY_SNOOPING
+ // Make a guess, based on the multi-packet query / known answer counts, whether we think we
+ // should have seen an answer for this. (We multiply MPQ by 4 and MPKA by 5, to allow for
+ // possible packet loss of up to 20% of the additional KA packets.)
+ else if (cr->MPUnansweredQ * 4 > cr->MPUnansweredKA * 5 + 8)
+ {
+ // We want to do this conservatively.
+ // If there are so many machines on the network that they have to use multi-packet known-answer lists,
+ // then we don't want them to all hit the network simultaneously with their final expiration queries.
+ // By setting the record to expire in four minutes, we achieve two things:
+ // (a) the 90-95% final expiration queries will be less bunched together
+ // (b) we allow some time for us to witness enough other failed queries that we don't have to do our own
+ mDNSu32 remain = (mDNSu32)(RRExpireTime(cr) - m->timenow) / 4;
+ if (remain > 240 * (mDNSu32)mDNSPlatformOneSecond)
+ remain = 240 * (mDNSu32)mDNSPlatformOneSecond;
+
+ // Only show debugging message if this record was not about to expire anyway
+ if (RRExpireTime(cr) - m->timenow > 4 * mDNSPlatformOneSecond)
+ debugf("ProcessQuery: (MPQ) UAQ %lu MPQ %lu MPKA %lu mDNS_Reconfirm() for %s",
+ cr->UnansweredQueries, cr->MPUnansweredQ, cr->MPUnansweredKA, CRDisplayString(m, cr));
+
+ if (remain <= 60 * (mDNSu32)mDNSPlatformOneSecond)
+ cr->UnansweredQueries++; // Treat this as equivalent to one definite unanswered query
+ cr->MPUnansweredQ = 0; // Clear MPQ/MPKA statistics
+ cr->MPUnansweredKA = 0;
+ cr->MPExpectingKA = mDNSfalse;
+
+ if (remain < kDefaultReconfirmTimeForNoAnswer)
+ remain = kDefaultReconfirmTimeForNoAnswer;
+ mDNS_Reconfirm_internal(m, cr, remain);
+ }
+#endif // ENABLE_MULTI_PACKET_QUERY_SNOOPING
+ }
+#endif // POOF_ENABLED
+
+ while (DupQuestions)
+ {
+ DNSQuestion *q = DupQuestions;
+ DupQuestions = q->NextInDQList;
+ q->NextInDQList = mDNSNULL;
+ i = RecordDupSuppressInfo(q->DupSuppress, m->timenow, InterfaceID, srcaddr->type);
+ debugf("ProcessQuery: Recorded DSI for %##s (%s) on %p/%s %d", q->qname.c, DNSTypeName(q->qtype), InterfaceID,
+ srcaddr->type == mDNSAddrType_IPv4 ? "v4" : "v6", i);
+ }
+
+ if (McastNSEC3Records)
+ {
+ debugf("ProcessQuery: McastNSEC3Records not used");
+ FreeNSECRecords(m, McastNSEC3Records);
+ }
+
+ return(responseptr);
+}
mDNSlocal void mDNSCoreReceiveQuery(mDNS *const m, const DNSMessage *const msg, const mDNSu8 *const end,
- const mDNSAddr *srcaddr, const mDNSIPPort srcport, const mDNSAddr *dstaddr, mDNSIPPort dstport,
- const mDNSInterfaceID InterfaceID)
- {
- mDNSu8 *responseend = mDNSNULL;
- mDNSBool QueryWasLocalUnicast = srcaddr && dstaddr &&
- !mDNSAddrIsDNSMulticast(dstaddr) && mDNS_AddressIsLocalSubnet(m, InterfaceID, srcaddr);
-
- if (!InterfaceID && dstaddr && mDNSAddrIsDNSMulticast(dstaddr))
- {
- LogMsg("Ignoring Query from %#-15a:%-5d to %#-15a:%-5d on 0x%p with "
- "%2d Question%s %2d Answer%s %2d Authorit%s %2d Additional%s %d bytes (Multicast, but no InterfaceID)",
- srcaddr, mDNSVal16(srcport), dstaddr, mDNSVal16(dstport), InterfaceID,
- msg->h.numQuestions, msg->h.numQuestions == 1 ? ", " : "s,",
- msg->h.numAnswers, msg->h.numAnswers == 1 ? ", " : "s,",
- msg->h.numAuthorities, msg->h.numAuthorities == 1 ? "y, " : "ies,",
- msg->h.numAdditionals, msg->h.numAdditionals == 1 ? " " : "s", end - msg->data);
- return;
- }
-
- verbosedebugf("Received Query from %#-15a:%-5d to %#-15a:%-5d on 0x%p with "
- "%2d Question%s %2d Answer%s %2d Authorit%s %2d Additional%s %d bytes",
- srcaddr, mDNSVal16(srcport), dstaddr, mDNSVal16(dstport), InterfaceID,
- msg->h.numQuestions, msg->h.numQuestions == 1 ? ", " : "s,",
- msg->h.numAnswers, msg->h.numAnswers == 1 ? ", " : "s,",
- msg->h.numAuthorities, msg->h.numAuthorities == 1 ? "y, " : "ies,",
- msg->h.numAdditionals, msg->h.numAdditionals == 1 ? " " : "s", end - msg->data);
-
- responseend = ProcessQuery(m, msg, end, srcaddr, InterfaceID,
- !mDNSSameIPPort(srcport, MulticastDNSPort), mDNSAddrIsDNSMulticast(dstaddr), QueryWasLocalUnicast, &m->omsg);
-
- if (responseend) // If responseend is non-null, that means we built a unicast response packet
- {
- debugf("Unicast Response: %d Question%s, %d Answer%s, %d Additional%s to %#-15a:%d on %p/%ld",
- m->omsg.h.numQuestions, m->omsg.h.numQuestions == 1 ? "" : "s",
- m->omsg.h.numAnswers, m->omsg.h.numAnswers == 1 ? "" : "s",
- m->omsg.h.numAdditionals, m->omsg.h.numAdditionals == 1 ? "" : "s",
- srcaddr, mDNSVal16(srcport), InterfaceID, srcaddr->type);
- mDNSSendDNSMessage(m, &m->omsg, responseend, InterfaceID, mDNSNULL, srcaddr, srcport, mDNSNULL, mDNSNULL);
- }
- }
+ const mDNSAddr *srcaddr, const mDNSIPPort srcport, const mDNSAddr *dstaddr, mDNSIPPort dstport,
+ const mDNSInterfaceID InterfaceID)
+{
+ mDNSu8 *responseend = mDNSNULL;
+ mDNSBool QueryWasLocalUnicast = srcaddr && dstaddr &&
+ !mDNSAddrIsDNSMulticast(dstaddr) && mDNS_AddressIsLocalSubnet(m, InterfaceID, srcaddr, mDNSNULL);
+
+ if (!InterfaceID && dstaddr && mDNSAddrIsDNSMulticast(dstaddr))
+ {
+ LogMsg("Ignoring Query from %#-15a:%-5d to %#-15a:%-5d on 0x%p with "
+ "%2d Question%s %2d Answer%s %2d Authorit%s %2d Additional%s %d bytes (Multicast, but no InterfaceID)",
+ srcaddr, mDNSVal16(srcport), dstaddr, mDNSVal16(dstport), InterfaceID,
+ msg->h.numQuestions, msg->h.numQuestions == 1 ? ", " : "s,",
+ msg->h.numAnswers, msg->h.numAnswers == 1 ? ", " : "s,",
+ msg->h.numAuthorities, msg->h.numAuthorities == 1 ? "y, " : "ies,",
+ msg->h.numAdditionals, msg->h.numAdditionals == 1 ? " " : "s", end - msg->data);
+ return;
+ }
+
+ verbosedebugf("Received Query from %#-15a:%-5d to %#-15a:%-5d on 0x%p with "
+ "%2d Question%s %2d Answer%s %2d Authorit%s %2d Additional%s %d bytes",
+ srcaddr, mDNSVal16(srcport), dstaddr, mDNSVal16(dstport), InterfaceID,
+ msg->h.numQuestions, msg->h.numQuestions == 1 ? ", " : "s,",
+ msg->h.numAnswers, msg->h.numAnswers == 1 ? ", " : "s,",
+ msg->h.numAuthorities, msg->h.numAuthorities == 1 ? "y, " : "ies,",
+ msg->h.numAdditionals, msg->h.numAdditionals == 1 ? " " : "s", end - msg->data);
+
+ responseend = ProcessQuery(m, msg, end, srcaddr, InterfaceID,
+ !mDNSSameIPPort(srcport, MulticastDNSPort), mDNSAddrIsDNSMulticast(dstaddr), QueryWasLocalUnicast, &m->omsg);
+
+ if (responseend) // If responseend is non-null, that means we built a unicast response packet
+ {
+ debugf("Unicast Response: %d Question%s, %d Answer%s, %d Additional%s to %#-15a:%d on %p/%ld",
+ m->omsg.h.numQuestions, m->omsg.h.numQuestions == 1 ? "" : "s",
+ m->omsg.h.numAnswers, m->omsg.h.numAnswers == 1 ? "" : "s",
+ m->omsg.h.numAdditionals, m->omsg.h.numAdditionals == 1 ? "" : "s",
+ srcaddr, mDNSVal16(srcport), InterfaceID, srcaddr->type);
+ mDNSSendDNSMessage(m, &m->omsg, responseend, InterfaceID, mDNSNULL, srcaddr, srcport, mDNSNULL, mDNSNULL, mDNSfalse);
+ }
+}
#if 0
mDNSlocal mDNSBool TrustedSource(const mDNS *const m, const mDNSAddr *const srcaddr)
- {
- DNSServer *s;
- (void)m; // Unused
- (void)srcaddr; // Unused
- for (s = m->DNSServers; s; s = s->next)
- if (mDNSSameAddress(srcaddr, &s->addr)) return(mDNStrue);
- return(mDNSfalse);
- }
+{
+ DNSServer *s;
+ (void)m; // Unused
+ (void)srcaddr; // Unused
+ for (s = m->DNSServers; s; s = s->next)
+ if (mDNSSameAddress(srcaddr, &s->addr)) return(mDNStrue);
+ return(mDNSfalse);
+}
#endif
struct UDPSocket_struct
- {
- mDNSIPPort port; // MUST BE FIRST FIELD -- mDNSCoreReceive expects every UDPSocket_struct to begin with mDNSIPPort port
- };
+{
+ mDNSIPPort port; // MUST BE FIRST FIELD -- mDNSCoreReceive expects every UDPSocket_struct to begin with mDNSIPPort port
+};
mDNSlocal DNSQuestion *ExpectingUnicastResponseForQuestion(const mDNS *const m, const mDNSIPPort port, const mDNSOpaque16 id, const DNSQuestion *const question, mDNSBool tcp)
- {
- DNSQuestion *q;
- for (q = m->Questions; q; q=q->next)
- {
- if (!tcp && !q->LocalSocket) continue;
- if (mDNSSameIPPort(tcp ? q->tcpSrcPort : q->LocalSocket->port, port) &&
- mDNSSameOpaque16(q->TargetQID, id) &&
- q->qtype == question->qtype &&
- q->qclass == question->qclass &&
- q->qnamehash == question->qnamehash &&
- SameDomainName(&q->qname, &question->qname))
- return(q);
- }
- return(mDNSNULL);
- }
+{
+ DNSQuestion *q;
+ for (q = m->Questions; q; q=q->next)
+ {
+ if (!tcp && !q->LocalSocket) continue;
+ if (mDNSSameIPPort(tcp ? q->tcpSrcPort : q->LocalSocket->port, port) &&
+ mDNSSameOpaque16(q->TargetQID, id) &&
+ q->qtype == question->qtype &&
+ q->qclass == question->qclass &&
+ q->qnamehash == question->qnamehash &&
+ SameDomainName(&q->qname, &question->qname))
+ return(q);
+ }
+ return(mDNSNULL);
+}
// This function is called when we receive a unicast response. This could be the case of a unicast response from the
// DNS server or a response to the QU query. Hence, the cache record's InterfaceId can be both NULL or non-NULL (QU case)
mDNSlocal DNSQuestion *ExpectingUnicastResponseForRecord(mDNS *const m,
- const mDNSAddr *const srcaddr, const mDNSBool SrcLocal, const mDNSIPPort port, const mDNSOpaque16 id, const CacheRecord *const rr, mDNSBool tcp)
- {
- DNSQuestion *q;
- (void)id;
- (void)srcaddr;
-
- for (q = m->Questions; q; q=q->next)
- {
- if (!q->DuplicateOf && ResourceRecordAnswersUnicastResponse(&rr->resrec, q))
- {
- if (!mDNSOpaque16IsZero(q->TargetQID))
- {
- debugf("ExpectingUnicastResponseForRecord msg->h.id %d q->TargetQID %d for %s", mDNSVal16(id), mDNSVal16(q->TargetQID), CRDisplayString(m, rr));
-
- if (mDNSSameOpaque16(q->TargetQID, id))
- {
- mDNSIPPort srcp;
- if (!tcp)
- {
- srcp = q->LocalSocket ? q->LocalSocket->port : zeroIPPort;
- }
- else
- {
- srcp = q->tcpSrcPort;
- }
- if (mDNSSameIPPort(srcp, port)) return(q);
-
- // if (mDNSSameAddress(srcaddr, &q->Target)) return(mDNStrue);
- // if (q->LongLived && mDNSSameAddress(srcaddr, &q->servAddr)) return(mDNStrue); Shouldn't need this now that we have LLQType checking
- // if (TrustedSource(m, srcaddr)) return(mDNStrue);
- LogInfo("WARNING: Ignoring suspect uDNS response for %##s (%s) [q->Target %#a:%d] from %#a:%d %s",
- q->qname.c, DNSTypeName(q->qtype), &q->Target, mDNSVal16(srcp), srcaddr, mDNSVal16(port), CRDisplayString(m, rr));
- return(mDNSNULL);
- }
- }
- else
- {
- if (SrcLocal && q->ExpectUnicastResp && (mDNSu32)(m->timenow - q->ExpectUnicastResp) < (mDNSu32)(mDNSPlatformOneSecond*2))
- return(q);
- }
- }
- }
- return(mDNSNULL);
- }
+ const mDNSAddr *const srcaddr, const mDNSBool SrcLocal, const mDNSIPPort port, const mDNSOpaque16 id, const CacheRecord *const rr, mDNSBool tcp)
+{
+ DNSQuestion *q;
+ (void)id;
+ (void)srcaddr;
+
+ for (q = m->Questions; q; q=q->next)
+ {
+ if (!q->DuplicateOf && ResourceRecordAnswersUnicastResponse(&rr->resrec, q))
+ {
+ if (!mDNSOpaque16IsZero(q->TargetQID))
+ {
+ debugf("ExpectingUnicastResponseForRecord msg->h.id %d q->TargetQID %d for %s", mDNSVal16(id), mDNSVal16(q->TargetQID), CRDisplayString(m, rr));
+
+ if (mDNSSameOpaque16(q->TargetQID, id))
+ {
+ mDNSIPPort srcp;
+ if (!tcp)
+ {
+ srcp = q->LocalSocket ? q->LocalSocket->port : zeroIPPort;
+ }
+ else
+ {
+ srcp = q->tcpSrcPort;
+ }
+ if (mDNSSameIPPort(srcp, port)) return(q);
+
+ // if (mDNSSameAddress(srcaddr, &q->Target)) return(mDNStrue);
+ // if (q->LongLived && mDNSSameAddress(srcaddr, &q->servAddr)) return(mDNStrue); Shouldn't need this now that we have LLQType checking
+ // if (TrustedSource(m, srcaddr)) return(mDNStrue);
+ LogInfo("WARNING: Ignoring suspect uDNS response for %##s (%s) [q->Target %#a:%d] from %#a:%d %s",
+ q->qname.c, DNSTypeName(q->qtype), &q->Target, mDNSVal16(srcp), srcaddr, mDNSVal16(port), CRDisplayString(m, rr));
+ return(mDNSNULL);
+ }
+ }
+ else
+ {
+ if (SrcLocal && q->ExpectUnicastResp && (mDNSu32)(m->timenow - q->ExpectUnicastResp) < (mDNSu32)(mDNSPlatformOneSecond*2))
+ return(q);
+ }
+ }
+ }
+ return(mDNSNULL);
+}
+
+// Return a pointer to the primary service name, skipping subtype name if present.
+mDNSlocal const domainname *getPrimaryServiceName(const domainname *domainName)
+{
+ const domainname *primaryName = domainName;
+ const domainname *subName = SkipLeadingLabels(domainName, 1);
+
+ if (SameDomainLabel(subName->c, (const mDNSu8 *)mDNSSubTypeLabel))
+ {
+ // skip "<sub type name>._sub" portion of name
+ primaryName = SkipLeadingLabels(domainName, 2);
+ debugf("getPrimaryServiceName: returning %##s for _sub type", primaryName);
+ }
+
+ return primaryName;
+}
+
+// This function is not called if the packet is from us, which implies that we accept all multicast packets coming from us.
+mDNSlocal mDNSBool ExpectingMulticastResponseForRecord(mDNS *const m, CacheRecord *rr, const mDNSAddr *srcaddr, mDNSBool recordAccepted,
+ CacheRecord **McastNSEC3Records)
+{
+ DNSQuestion *q;
+
+ // Accept A and AAAA if we accepted something before in the same packet as most likely related to the
+ // service records that we may have accepted.
+ if (recordAccepted && (rr->resrec.rrtype == kDNSType_A || rr->resrec.rrtype == kDNSType_AAAA))
+ {
+ LogInfo("ExpectingMulticastResponseForRecord:A:AAAA: accepting %s, from %#a due to same packet %d", CRDisplayString(m, rr), srcaddr, m->PktNum);
+ return mDNStrue;
+ }
+ for (q = m->Questions; q; q=q->next)
+ {
+ if (!q->DuplicateOf && mDNSOpaque16IsZero(q->TargetQID))
+ {
+ mDNSBool ret;
+ // 1. If a resource record answers question, cache it. This also will cache NSECs if it asserts
+ // non-existence of q->qtype. If we have any matching NSEC3 Records for the question, send
+ // it along with the resource record. Do it only for questions that are expecting to
+ // discover only its peers (q->AnonInfo not NULL)
+ if (q->AnonInfo && McastNSEC3Records && !rr->resrec.AnonInfo)
+ {
+ InitializeAnonInfoForCR(m, McastNSEC3Records, rr);
+ }
+ ret = ResourceRecordAnswersQuestion(&rr->resrec, q);
+ if (ret)
+ {
+ // The record and the question belong to the same subset. Set the
+ // anonymous data in the cache record.
+ if (q->AnonInfo && rr->resrec.AnonInfo)
+ {
+ SetAnonData(q, &rr->resrec, mDNSfalse);
+ }
+ LogInfo("ExpectingMulticastResponseForRecord: Name and Type match, accepting %s, from %#a", CRDisplayString(m, rr), srcaddr);
+ if (rr->resrec.rrtype == kDNSType_NSEC)
+ LogInfo("ExpectingMulticastResponseForRecord: record %s, question %##s (%s)", CRDisplayString(m, rr), q->qname.c, DNSTypeName(q->qtype));
+ return mDNStrue;
+ }
+ if (rr->resrec.rrtype == kDNSType_SRV || rr->resrec.rrtype == kDNSType_TXT)
+ {
+ // Point to the service type in the record name
+ const domainname *name = SkipLeadingLabels(rr->resrec.name, 1);
+
+ // If question is for a sub type, just compare against the primary service type
+ const domainname *primaryName = getPrimaryServiceName(&q->qname);
+
+ // 2. If the SRV or TXT record matches the service name, then cache it. If the TXT or SRV record is
+ // before the PTR record in the packet, PTR record may not be in the cache yet and hence the logic
+ // in (3) below will fail to cache it.
+ if (q->qtype == kDNSType_PTR && name && SameDomainName(primaryName, name))
+ {
+ LogInfo("ExpectingMulticastResponseForRecord: Accepting %s due to PTR match, question %##s from %#a, pktnum %d",
+ CRDisplayString(m, rr), q->qname.c, srcaddr, m->PktNum);
+ return mDNStrue;
+ }
+
+ if (name)
+ {
+ const mDNSu32 slot = HashSlot(name);
+ const mDNSu32 namehash = DomainNameHashValue(name);
+ CacheGroup *cg = CacheGroupForName(m, slot, namehash, name);
+ CacheRecord *cr;
+
+ // 3. Same as in (2), but look in the cache in case we don't have the PTR question.
+
+ for (cr = cg ? cg->members : mDNSNULL; cr; cr=cr->next)
+ {
+ if (cr->resrec.rrtype == kDNSType_PTR)
+ {
+ primaryName = getPrimaryServiceName(cr->resrec.name);
+
+ if (SameDomainName(primaryName, name))
+ {
+ LogInfo("ExpectingMulticastResponseForRecord: accepting %s, from %#a, pktnum %d",
+ CRDisplayString(m, rr), srcaddr, m->PktNum);
+ return mDNStrue;
+ }
+ }
+ }
+ }
+ }
+ }
+ }
+ debugf("ExpectingMulticastResponseForRecord: discarding %s, from %#a, pktnum %d", CRDisplayString(m, rr), srcaddr, m->PktNum);
+ return(mDNSfalse);
+}
// Certain data types need more space for in-memory storage than their in-packet rdlength would imply
// Currently this applies only to rdata types containing more than one domainname,
// or types where the domainname is not the last item in the structure.
-// In addition, NSEC currently requires less space for in-memory storage than its in-packet representation.
mDNSlocal mDNSu16 GetRDLengthMem(const ResourceRecord *const rr)
- {
- switch (rr->rrtype)
- {
- case kDNSType_SOA: return sizeof(rdataSOA);
- case kDNSType_RP: return sizeof(rdataRP);
- case kDNSType_PX: return sizeof(rdataPX);
- case kDNSType_NSEC:return sizeof(rdataNSEC);
- default: return rr->rdlength;
- }
- }
-
-mDNSexport CacheRecord *CreateNewCacheEntry(mDNS *const m, const mDNSu32 slot, CacheGroup *cg, mDNSs32 delay)
- {
- CacheRecord *rr = mDNSNULL;
- mDNSu16 RDLength = GetRDLengthMem(&m->rec.r.resrec);
-
- if (!m->rec.r.resrec.InterfaceID) debugf("CreateNewCacheEntry %s", CRDisplayString(m, &m->rec.r));
-
- //if (RDLength > InlineCacheRDSize)
- // LogInfo("Rdata len %4d > InlineCacheRDSize %d %s", RDLength, InlineCacheRDSize, CRDisplayString(m, &m->rec.r));
-
- if (!cg) cg = GetCacheGroup(m, slot, &m->rec.r.resrec); // If we don't have a CacheGroup for this name, make one now
- if (cg) rr = GetCacheRecord(m, cg, RDLength); // Make a cache record, being careful not to recycle cg
- if (!rr) NoCacheAnswer(m, &m->rec.r);
- else
- {
- RData *saveptr = rr->resrec.rdata; // Save the rr->resrec.rdata pointer
- *rr = m->rec.r; // Block copy the CacheRecord object
- rr->resrec.rdata = saveptr; // Restore rr->resrec.rdata after the structure assignment
- rr->resrec.name = cg->name; // And set rr->resrec.name to point into our CacheGroup header
- rr->DelayDelivery = delay;
-
- // If this is an oversized record with external storage allocated, copy rdata to external storage
- if (rr->resrec.rdata == (RData*)&rr->smallrdatastorage && RDLength > InlineCacheRDSize)
- LogMsg("rr->resrec.rdata == &rr->rdatastorage but length > InlineCacheRDSize %##s", m->rec.r.resrec.name->c);
- else if (rr->resrec.rdata != (RData*)&rr->smallrdatastorage && RDLength <= InlineCacheRDSize)
- LogMsg("rr->resrec.rdata != &rr->rdatastorage but length <= InlineCacheRDSize %##s", m->rec.r.resrec.name->c);
- if (RDLength > InlineCacheRDSize)
- mDNSPlatformMemCopy(rr->resrec.rdata, m->rec.r.resrec.rdata, sizeofRDataHeader + RDLength);
-
- rr->next = mDNSNULL; // Clear 'next' pointer
- *(cg->rrcache_tail) = rr; // Append this record to tail of cache slot list
- cg->rrcache_tail = &(rr->next); // Advance tail pointer
-
- CacheRecordAdd(m, rr); // CacheRecordAdd calls SetNextCacheCheckTimeForRecord(m, rr); for us
- }
- return(rr);
- }
+{
+ switch (rr->rrtype)
+ {
+ case kDNSType_SOA: return sizeof(rdataSOA);
+ case kDNSType_RP: return sizeof(rdataRP);
+ case kDNSType_PX: return sizeof(rdataPX);
+ default: return rr->rdlength;
+ }
+}
+
+mDNSexport CacheRecord *CreateNewCacheEntry(mDNS *const m, const mDNSu32 slot, CacheGroup *cg, mDNSs32 delay, mDNSBool Add, const mDNSAddr *sourceAddress)
+{
+ CacheRecord *rr = mDNSNULL;
+ mDNSu16 RDLength = GetRDLengthMem(&m->rec.r.resrec);
+
+ if (!m->rec.r.resrec.InterfaceID) debugf("CreateNewCacheEntry %s", CRDisplayString(m, &m->rec.r));
+
+ //if (RDLength > InlineCacheRDSize)
+ // LogInfo("Rdata len %4d > InlineCacheRDSize %d %s", RDLength, InlineCacheRDSize, CRDisplayString(m, &m->rec.r));
+
+ if (!cg) cg = GetCacheGroup(m, slot, &m->rec.r.resrec); // If we don't have a CacheGroup for this name, make one now
+ if (cg) rr = GetCacheRecord(m, cg, RDLength); // Make a cache record, being careful not to recycle cg
+ if (!rr) NoCacheAnswer(m, &m->rec.r);
+ else
+ {
+ RData *saveptr = rr->resrec.rdata; // Save the rr->resrec.rdata pointer
+ *rr = m->rec.r; // Block copy the CacheRecord object
+ rr->resrec.rdata = saveptr; // Restore rr->resrec.rdata after the structure assignment
+ rr->resrec.name = cg->name; // And set rr->resrec.name to point into our CacheGroup header
+
+ // We need to add the anonymous info before we call CacheRecordAdd so that
+ // if it finds a matching question with this record, it bumps up the counters like
+ // CurrentAnswers etc. Otherwise, when a cache entry gets removed, CacheRecordRmv
+ // will complain.
+ if (m->rec.r.resrec.AnonInfo)
+ {
+ rr->resrec.AnonInfo = m->rec.r.resrec.AnonInfo;
+ m->rec.r.resrec.AnonInfo = mDNSNULL;
+ }
+ rr->DelayDelivery = delay;
+
+ // If this is an oversized record with external storage allocated, copy rdata to external storage
+ if (rr->resrec.rdata == (RData*)&rr->smallrdatastorage && RDLength > InlineCacheRDSize)
+ LogMsg("rr->resrec.rdata == &rr->rdatastorage but length > InlineCacheRDSize %##s", m->rec.r.resrec.name->c);
+ else if (rr->resrec.rdata != (RData*)&rr->smallrdatastorage && RDLength <= InlineCacheRDSize)
+ LogMsg("rr->resrec.rdata != &rr->rdatastorage but length <= InlineCacheRDSize %##s", m->rec.r.resrec.name->c);
+ if (RDLength > InlineCacheRDSize)
+ mDNSPlatformMemCopy(rr->resrec.rdata, m->rec.r.resrec.rdata, sizeofRDataHeader + RDLength);
+
+ rr->next = mDNSNULL; // Clear 'next' pointer
+ rr->nsec = mDNSNULL;
+ rr->soa = mDNSNULL;
+
+ if (sourceAddress)
+ rr->sourceAddress = *sourceAddress;
+
+ if (!rr->resrec.InterfaceID)
+ {
+ m->rrcache_totalused_unicast += rr->resrec.rdlength;
+ if (DNSSECRecordType(rr->resrec.rrtype))
+ BumpDNSSECStats(m, kStatsActionIncrement, kStatsTypeMemoryUsage, rr->resrec.rdlength);
+ }
+
+ if (Add)
+ {
+ *(cg->rrcache_tail) = rr; // Append this record to tail of cache slot list
+ cg->rrcache_tail = &(rr->next); // Advance tail pointer
+ CacheRecordAdd(m, rr); // CacheRecordAdd calls SetNextCacheCheckTimeForRecord(m, rr); for us
+ }
+ else
+ {
+ // Can't use the "cg->name" if we are not adding to the cache as the
+ // CacheGroup may be released anytime if it is empty
+ domainname *name = mDNSPlatformMemAllocate(DomainNameLength(cg->name));
+ if (name)
+ {
+ AssignDomainName(name, cg->name);
+ rr->resrec.name = name;
+ }
+ else
+ {
+ ReleaseCacheRecord(m, rr);
+ NoCacheAnswer(m, &m->rec.r);
+ rr = mDNSNULL;
+ }
+ }
+ }
+ return(rr);
+}
mDNSlocal void RefreshCacheRecord(mDNS *const m, CacheRecord *rr, mDNSu32 ttl)
- {
- rr->TimeRcvd = m->timenow;
- rr->resrec.rroriginalttl = ttl;
- rr->UnansweredQueries = 0;
+{
+ rr->TimeRcvd = m->timenow;
+ rr->resrec.rroriginalttl = ttl;
+ rr->UnansweredQueries = 0;
#if ENABLE_MULTI_PACKET_QUERY_SNOOPING
- rr->MPUnansweredQ = 0;
- rr->MPUnansweredKA = 0;
- rr->MPExpectingKA = mDNSfalse;
+ rr->MPUnansweredQ = 0;
+ rr->MPUnansweredKA = 0;
+ rr->MPExpectingKA = mDNSfalse;
#endif
- SetNextCacheCheckTimeForRecord(m, rr);
- }
+ SetNextCacheCheckTimeForRecord(m, rr);
+}
mDNSexport void GrantCacheExtensions(mDNS *const m, DNSQuestion *q, mDNSu32 lease)
- {
- CacheRecord *rr;
- const mDNSu32 slot = HashSlot(&q->qname);
- CacheGroup *cg = CacheGroupForName(m, slot, q->qnamehash, &q->qname);
- for (rr = cg ? cg->members : mDNSNULL; rr; rr=rr->next)
- if (rr->CRActiveQuestion == q)
- {
- //LogInfo("GrantCacheExtensions: new lease %d / %s", lease, CRDisplayString(m, rr));
- RefreshCacheRecord(m, rr, lease);
- }
- }
-
-mDNSlocal mDNSu32 GetEffectiveTTL(const uDNS_LLQType LLQType, mDNSu32 ttl) // TTL in seconds
- {
- if (LLQType == uDNS_LLQ_Entire) ttl = kLLQ_DefLease;
- else if (LLQType == uDNS_LLQ_Events)
- {
- // If the TTL is -1 for uDNS LLQ event packet, that means "remove"
- if (ttl == 0xFFFFFFFF) ttl = 0;
- else ttl = kLLQ_DefLease;
- }
- else // else not LLQ (standard uDNS response)
- {
- // The TTL is already capped to a maximum value in GetLargeResourceRecord, but just to be extra safe we
- // also do this check here to make sure we can't get overflow below when we add a quarter to the TTL
- if (ttl > 0x60000000UL / mDNSPlatformOneSecond) ttl = 0x60000000UL / mDNSPlatformOneSecond;
-
- // Adjustment factor to avoid race condition:
- // Suppose real record as TTL of 3600, and our local caching server has held it for 3500 seconds, so it returns an aged TTL of 100.
- // If we do our normal refresh at 80% of the TTL, our local caching server will return 20 seconds, so we'll do another
- // 80% refresh after 16 seconds, and then the server will return 4 seconds, and so on, in the fashion of Zeno's paradox.
- // To avoid this, we extend the record's effective TTL to give it a little extra grace period.
- // We adjust the 100 second TTL to 126. This means that when we do our 80% query at 101 seconds,
- // the cached copy at our local caching server will already have expired, so the server will be forced
- // to fetch a fresh copy from the authoritative server, and then return a fresh record with the full TTL of 3600 seconds.
- ttl += ttl/4 + 2;
-
- // For mDNS, TTL zero means "delete this record"
- // For uDNS, TTL zero means: this data is true at this moment, but don't cache it.
- // For the sake of network efficiency, we impose a minimum effective TTL of 15 seconds.
- // This means that we'll do our 80, 85, 90, 95% queries at 12.00, 12.75, 13.50, 14.25 seconds
- // respectively, and then if we get no response, delete the record from the cache at 15 seconds.
- // This gives the server up to three seconds to respond between when we send our 80% query at 12 seconds
- // and when we delete the record at 15 seconds. Allowing cache lifetimes less than 15 seconds would
- // (with the current code) result in the server having even less than three seconds to respond
- // before we deleted the record and reported a "remove" event to any active questions.
- // Furthermore, with the current code, if we were to allow a TTL of less than 2 seconds
- // then things really break (e.g. we end up making a negative cache entry).
- // In the future we may want to revisit this and consider properly supporting non-cached (TTL=0) uDNS answers.
- if (ttl < 15) ttl = 15;
- }
-
- return ttl;
- }
+{
+ CacheRecord *rr;
+ const mDNSu32 slot = HashSlot(&q->qname);
+ CacheGroup *cg = CacheGroupForName(m, slot, q->qnamehash, &q->qname);
+ for (rr = cg ? cg->members : mDNSNULL; rr; rr=rr->next)
+ if (rr->CRActiveQuestion == q)
+ {
+ //LogInfo("GrantCacheExtensions: new lease %d / %s", lease, CRDisplayString(m, rr));
+ RefreshCacheRecord(m, rr, lease);
+ }
+}
+
+mDNSlocal mDNSu32 GetEffectiveTTL(const uDNS_LLQType LLQType, mDNSu32 ttl) // TTL in seconds
+{
+ if (LLQType == uDNS_LLQ_Entire) ttl = kLLQ_DefLease;
+ else if (LLQType == uDNS_LLQ_Events)
+ {
+ // If the TTL is -1 for uDNS LLQ event packet, that means "remove"
+ if (ttl == 0xFFFFFFFF) ttl = 0;
+ else ttl = kLLQ_DefLease;
+ }
+ else // else not LLQ (standard uDNS response)
+ {
+ // The TTL is already capped to a maximum value in GetLargeResourceRecord, but just to be extra safe we
+ // also do this check here to make sure we can't get overflow below when we add a quarter to the TTL
+ if (ttl > 0x60000000UL / mDNSPlatformOneSecond) ttl = 0x60000000UL / mDNSPlatformOneSecond;
+
+ ttl = RRAdjustTTL(ttl);
+
+ // For mDNS, TTL zero means "delete this record"
+ // For uDNS, TTL zero means: this data is true at this moment, but don't cache it.
+ // For the sake of network efficiency, we impose a minimum effective TTL of 15 seconds.
+ // This means that we'll do our 80, 85, 90, 95% queries at 12.00, 12.75, 13.50, 14.25 seconds
+ // respectively, and then if we get no response, delete the record from the cache at 15 seconds.
+ // This gives the server up to three seconds to respond between when we send our 80% query at 12 seconds
+ // and when we delete the record at 15 seconds. Allowing cache lifetimes less than 15 seconds would
+ // (with the current code) result in the server having even less than three seconds to respond
+ // before we deleted the record and reported a "remove" event to any active questions.
+ // Furthermore, with the current code, if we were to allow a TTL of less than 2 seconds
+ // then things really break (e.g. we end up making a negative cache entry).
+ // In the future we may want to revisit this and consider properly supporting non-cached (TTL=0) uDNS answers.
+ if (ttl < 15) ttl = 15;
+ }
+
+ return ttl;
+}
+
+// When the response does not match the question directly, we still want to cache them sometimes. The current response is
+// in m->rec.
+mDNSlocal mDNSBool IsResponseAcceptable(mDNS *const m, const CacheRecord *crlist, DNSQuestion *q, mDNSBool *nseclist)
+{
+ CacheRecord *const newcr = &m->rec.r;
+ ResourceRecord *rr = &newcr->resrec;
+ const CacheRecord *cr;
+
+ *nseclist = mDNSfalse;
+ for (cr = crlist; cr != (CacheRecord*)1; cr = cr->NextInCFList)
+ {
+ domainname *target = GetRRDomainNameTarget(&cr->resrec);
+ // When we issue a query for A record, the response might contain both a CNAME and A records. Only the CNAME would
+ // match the question and we already created a cache entry in the previous pass of this loop. Now when we process
+ // the A record, it does not match the question because the record name here is the CNAME. Hence we try to
+ // match with the previous records to make it an AcceptableResponse. We have to be careful about setting the
+ // DNSServer value that we got in the previous pass. This can happen for other record types like SRV also.
+
+ if (target && cr->resrec.rdatahash == rr->namehash && SameDomainName(target, rr->name))
+ {
+ LogInfo("IsResponseAcceptable: Found a matching entry for %##s in the CacheFlushRecords %s", rr->name->c, CRDisplayString(m, cr));
+ return (mDNStrue);
+ }
+ }
+
+ // Either the question requires validation or we are validating a response with DNSSEC in which case
+ // we need to accept the RRSIGs also so that we can validate the response. It is also possible that
+ // we receive NSECs for our query which does not match the qname and we need to cache in that case
+ // too. nseclist is set if they have to be cached as part of the negative cache record.
+ if (q && DNSSECQuestion(q))
+ {
+ mDNSBool same = SameDomainName(&q->qname, rr->name);
+ if (same && (q->qtype == rr->rrtype || rr->rrtype == kDNSType_CNAME))
+ {
+ LogInfo("IsResponseAcceptable: Accepting, same name and qtype %s, CR %s", DNSTypeName(q->qtype),
+ CRDisplayString(m, newcr));
+ return mDNStrue;
+ }
+ // We cache RRSIGS if it covers the question type or NSEC. If it covers a NSEC,
+ // "nseclist" is set
+ if (rr->rrtype == kDNSType_RRSIG)
+ {
+ RDataBody2 *const rdb = (RDataBody2 *)newcr->smallrdatastorage.data;
+ rdataRRSig *rrsig = &rdb->rrsig;
+ mDNSu16 typeCovered = swap16(rrsig->typeCovered);
+
+ // Note the ordering. If we are looking up the NSEC record, then the RRSIG's typeCovered
+ // would match the qtype and they are cached normally as they are not used to prove the
+ // non-existence of any name. In that case, it is like any other normal dnssec validation
+ // and hence nseclist should not be set.
+
+ if (same && ((typeCovered == q->qtype) || (typeCovered == kDNSType_CNAME)))
+ {
+ LogInfo("IsResponseAcceptable: Accepting RRSIG %s matches question type %s", CRDisplayString(m, newcr),
+ DNSTypeName(q->qtype));
+ return mDNStrue;
+ }
+ else if (typeCovered == kDNSType_NSEC || typeCovered == kDNSType_NSEC3)
+ {
+ LogInfo("IsResponseAcceptable: Accepting RRSIG %s matches %s type (nseclist = 1)", CRDisplayString(m, newcr), DNSTypeName(typeCovered));
+ *nseclist = mDNStrue;
+ return mDNStrue;
+ }
+ else if (typeCovered == kDNSType_SOA)
+ {
+ LogInfo("IsResponseAcceptable: Accepting RRSIG %s matches SOA type (nseclist = 1)", CRDisplayString(m, newcr));
+ *nseclist = mDNStrue;
+ return mDNStrue;
+ }
+ else return mDNSfalse;
+ }
+ if (rr->rrtype == kDNSType_NSEC)
+ {
+ if (!UNICAST_NSEC(rr))
+ {
+ LogMsg("IsResponseAcceptable: ERROR!! Not a unicast NSEC %s", CRDisplayString(m, newcr));
+ return mDNSfalse;
+ }
+ LogInfo("IsResponseAcceptable: Accepting NSEC %s (nseclist = 1)", CRDisplayString(m, newcr));
+ *nseclist = mDNStrue;
+ return mDNStrue;
+ }
+ if (rr->rrtype == kDNSType_SOA)
+ {
+ LogInfo("IsResponseAcceptable: Accepting SOA %s (nseclist = 1)", CRDisplayString(m, newcr));
+ *nseclist = mDNStrue;
+ return mDNStrue;
+ }
+ else if (rr->rrtype == kDNSType_NSEC3)
+ {
+ LogInfo("IsResponseAcceptable: Accepting NSEC3 %s (nseclist = 1)", CRDisplayString(m, newcr));
+ *nseclist = mDNStrue;
+ return mDNStrue;
+ }
+ }
+ return mDNSfalse;
+}
+
+mDNSlocal void FreeNSECRecords(mDNS *const m, CacheRecord *NSECRecords)
+{
+ CacheRecord *rp, *next;
+
+ for (rp = NSECRecords; rp; rp = next)
+ {
+ next = rp->next;
+ ReleaseCacheRecord(m, rp);
+ }
+}
+
+// If we received zero DNSSEC records even when the DO/EDNS0 bit was set, we need to provide this
+// information to ValidatingResponse question to indicate the DNSSEC status to the application
+mDNSlocal void mDNSCoreReceiveNoDNSSECAnswers(mDNS *const m, const DNSMessage *const response, const mDNSu8 *end, const mDNSAddr *dstaddr,
+ mDNSIPPort dstport, const mDNSInterfaceID InterfaceID)
+{
+ int i;
+ const mDNSu8 *ptr = response->data;
+
+ for (i = 0; i < response->h.numQuestions && ptr && ptr < end; i++)
+ {
+ DNSQuestion pktq;
+ DNSQuestion *qptr = mDNSNULL;
+ ptr = getQuestion(response, ptr, end, InterfaceID, &pktq);
+ if (ptr && (qptr = ExpectingUnicastResponseForQuestion(m, dstport, response->h.id, &pktq, !dstaddr)) &&
+ qptr->ValidatingResponse)
+ {
+ DNSQuestion *next, *q;
+
+ if (qptr->DuplicateOf)
+ LogMsg("mDNSCoreReceiveNoDNSSECAnswers: ERROR!! qptr %##s (%s) Duplicate question matching response", qptr->qname.c, DNSTypeName(qptr->qtype));
+
+ // Be careful to call the callback for duplicate questions first and then the original
+ // question. If we called the callback on the original question, it could stop and
+ // a duplicate question would become the original question.
+ mDNS_DropLockBeforeCallback(); // Allow client (and us) to legally make mDNS API calls
+ for (q = qptr->next ; q && q != m->NewQuestions; q = next)
+ {
+ next = q->next;
+ if (q->DuplicateOf == qptr)
+ {
+ if (q->ValidatingResponse)
+ LogInfo("mDNSCoreReceiveNoDNSSECAnswers: qptr %##s (%s) Duplicate question found", q->qname.c, DNSTypeName(q->qtype));
+ else
+ LogMsg("mDNSCoreReceiveNoDNSSECAnswers: ERROR!! qptr %##s (%s) Duplicate question not ValidatingResponse", q->qname.c, DNSTypeName(q->qtype));
+ if (q->QuestionCallback)
+ q->QuestionCallback(m, q, mDNSNULL, QC_nodnssec);
+ }
+ }
+ if (qptr->QuestionCallback)
+ qptr->QuestionCallback(m, qptr, mDNSNULL, QC_nodnssec);
+ mDNS_ReclaimLockAfterCallback(); // Decrement mDNS_reentrancy to block mDNS API calls again
+ }
+ }
+}
+
+mDNSlocal void mDNSCoreReceiveNoUnicastAnswers(mDNS *const m, const DNSMessage *const response, const mDNSu8 *end, const mDNSAddr *dstaddr,
+ mDNSIPPort dstport, const mDNSInterfaceID InterfaceID, uDNS_LLQType LLQType, mDNSu8 rcode, CacheRecord *NSECRecords)
+{
+ int i;
+ const mDNSu8 *ptr = response->data;
+ CacheRecord *SOARecord = mDNSNULL;
+
+ for (i = 0; i < response->h.numQuestions && ptr && ptr < end; i++)
+ {
+ DNSQuestion q;
+ DNSQuestion *qptr = mDNSNULL;
+ ptr = getQuestion(response, ptr, end, InterfaceID, &q);
+ if (ptr && (qptr = ExpectingUnicastResponseForQuestion(m, dstport, response->h.id, &q, !dstaddr)))
+ {
+ CacheRecord *rr, *neg = mDNSNULL;
+ mDNSu32 slot = HashSlot(&q.qname);
+ CacheGroup *cg = CacheGroupForName(m, slot, q.qnamehash, &q.qname);
+ for (rr = cg ? cg->members : mDNSNULL; rr; rr=rr->next)
+ if (SameNameRecordAnswersQuestion(&rr->resrec, qptr))
+ {
+ // 1. If we got a fresh answer to this query, then don't need to generate a negative entry
+ if (RRExpireTime(rr) - m->timenow > 0) break;
+ // 2. If we already had a negative entry, keep track of it so we can resurrect it instead of creating a new one
+ if (rr->resrec.RecordType == kDNSRecordTypePacketNegative) neg = rr;
+ }
+ // When we're doing parallel unicast and multicast queries for dot-local names (for supporting Microsoft
+ // Active Directory sites) we don't want to waste memory making negative cache entries for all the unicast answers.
+ // Otherwise we just fill up our cache with negative entries for just about every single multicast name we ever look up
+ // (since the Microsoft Active Directory server is going to assert that pretty much every single multicast name doesn't exist).
+ // This is not only a waste of memory, but there's also the problem of those negative entries confusing us later -- e.g. we
+ // suppress sending our mDNS query packet because we think we already have a valid (negative) answer to that query in our cache.
+ // The one exception is that we *DO* want to make a negative cache entry for "local. SOA", for the (common) case where we're
+ // *not* on a Microsoft Active Directory network, and there is no authoritative server for "local". Note that this is not
+ // in conflict with the mDNS spec, because that spec says, "Multicast DNS Zones have no SOA record," so it's okay to cache
+ // negative answers for "local. SOA" from a uDNS server, because the mDNS spec already says that such records do not exist :-)
+ //
+ // By suppressing negative responses, it might take longer to timeout a .local question as it might be expecting a
+ // response e.g., we deliver a positive "A" response and suppress negative "AAAA" response and the upper layer may
+ // be waiting longer to get the AAAA response before returning the "A" response to the application. To handle this
+ // case without creating the negative cache entries, we generate a negative response and let the layer above us
+ // do the appropriate thing. This negative response is also needed for appending new search domains.
+ if (!InterfaceID && q.qtype != kDNSType_SOA && IsLocalDomain(&q.qname))
+ {
+ if (!rr)
+ {
+ LogInfo("mDNSCoreReceiveNoUnicastAnswers: Generate negative response for %##s (%s)", q.qname.c, DNSTypeName(q.qtype));
+ m->CurrentQuestion = qptr;
+ // We are not creating a cache record in this case, we need to pass back
+ // the error we got so that the proxy code can return the right one to
+ // the application
+ if (qptr->ProxyQuestion)
+ qptr->responseFlags = response->h.flags;
+ GenerateNegativeResponse(m, QC_forceresponse);
+ m->CurrentQuestion = mDNSNULL;
+ }
+ else
+ {
+ LogInfo("mDNSCoreReceiveNoUnicastAnswers: Skipping check and not creating a negative cache entry for %##s (%s)", q.qname.c, DNSTypeName(q.qtype));
+ }
+ }
+ else
+ {
+ if (!rr)
+ {
+ // We start off assuming a negative caching TTL of 60 seconds
+ // but then look to see if we can find an SOA authority record to tell us a better value we should be using
+ mDNSu32 negttl = 60;
+ int repeat = 0;
+ const domainname *name = &q.qname;
+ mDNSu32 hash = q.qnamehash;
+
+ // Special case for our special Microsoft Active Directory "local SOA" check.
+ // Some cheap home gateways don't include an SOA record in the authority section when
+ // they send negative responses, so we don't know how long to cache the negative result.
+ // Because we don't want to keep hitting the root name servers with our query to find
+ // if we're on a network using Microsoft Active Directory using "local" as a private
+ // internal top-level domain, we make sure to cache the negative result for at least one day.
+ if (q.qtype == kDNSType_SOA && SameDomainName(&q.qname, &localdomain)) negttl = 60 * 60 * 24;
+
+ // If we're going to make (or update) a negative entry, then look for the appropriate TTL from the SOA record
+ if (response->h.numAuthorities && (ptr = LocateAuthorities(response, end)) != mDNSNULL)
+ {
+ ptr = GetLargeResourceRecord(m, response, ptr, end, InterfaceID, kDNSRecordTypePacketAuth, &m->rec);
+ if (ptr && m->rec.r.resrec.RecordType != kDNSRecordTypePacketNegative && m->rec.r.resrec.rrtype == kDNSType_SOA)
+ {
+ const mDNSu32 s = HashSlot(m->rec.r.resrec.name);
+ CacheGroup *cgSOA = CacheGroupForRecord(m, s, &m->rec.r.resrec);
+ const rdataSOA *const soa = (const rdataSOA *)m->rec.r.resrec.rdata->u.data;
+ mDNSu32 ttl_s = soa->min;
+ // We use the lesser of the SOA.MIN field and the SOA record's TTL, *except*
+ // for the SOA record for ".", where the record is reported as non-cacheable
+ // (TTL zero) for some reason, so in this case we just take the SOA record's TTL as-is
+ if (ttl_s > m->rec.r.resrec.rroriginalttl && m->rec.r.resrec.name->c[0])
+ ttl_s = m->rec.r.resrec.rroriginalttl;
+ if (negttl < ttl_s) negttl = ttl_s;
+
+ // Create the SOA record as we may have to return this to the questions
+ // that we are acting as a proxy for currently or in the future.
+ SOARecord = CreateNewCacheEntry(m, s, cgSOA, 1, mDNSfalse, mDNSNULL);
+
+ // Special check for SOA queries: If we queried for a.b.c.d.com, and got no answer,
+ // with an Authority Section SOA record for d.com, then this is a hint that the authority
+ // is d.com, and consequently SOA records b.c.d.com and c.d.com don't exist either.
+ // To do this we set the repeat count so the while loop below will make a series of negative cache entries for us
+ //
+ // For ProxyQuestions, we don't do this as we need to create additional SOA records to cache them
+ // along with the negative cache record. For simplicity, we don't create the additional records.
+ if (!qptr->ProxyQuestion && q.qtype == kDNSType_SOA)
+ {
+ int qcount = CountLabels(&q.qname);
+ int scount = CountLabels(m->rec.r.resrec.name);
+ if (qcount - 1 > scount)
+ if (SameDomainName(SkipLeadingLabels(&q.qname, qcount - scount), m->rec.r.resrec.name))
+ repeat = qcount - 1 - scount;
+ }
+ }
+ m->rec.r.resrec.RecordType = 0; // Clear RecordType to show we're not still using it
+ }
+
+ // If we already had a negative entry in the cache, then we double our existing negative TTL. This is to avoid
+ // the case where the record doesn't exist (e.g. particularly for things like our lb._dns-sd._udp.<domain> query),
+ // and the server returns no SOA record (or an SOA record with a small MIN TTL) so we assume a TTL
+ // of 60 seconds, and we end up polling the server every minute for a record that doesn't exist.
+ // With this fix in place, when this happens, we double the effective TTL each time (up to one hour),
+ // so that we back off our polling rate and don't keep hitting the server continually.
+ if (neg)
+ {
+ if (negttl < neg->resrec.rroriginalttl * 2)
+ negttl = neg->resrec.rroriginalttl * 2;
+ if (negttl > 3600)
+ negttl = 3600;
+ }
+
+ negttl = GetEffectiveTTL(LLQType, negttl); // Add 25% grace period if necessary
+
+ // If we already had a negative cache entry just update it, else make one or more new negative cache entries.
+ if (neg)
+ {
+ LogInfo("mDNSCoreReceiveNoUnicastAnswers: Renewing negative TTL from %d to %d %s", neg->resrec.rroriginalttl, negttl, CRDisplayString(m, neg));
+ RefreshCacheRecord(m, neg, negttl);
+ // When we created the cache for the first time and answered the question, the question's
+ // interval was set to MaxQuestionInterval. If the cache is about to expire and we are resending
+ // the queries, the interval should still be at MaxQuestionInterval. If the query is being
+ // restarted (setting it to InitialQuestionInterval) for other reasons e.g., wakeup,
+ // we should reset its question interval here to MaxQuestionInterval.
+ ResetQuestionState(m, qptr);
+ if (DNSSECQuestion(qptr))
+ neg->CRDNSSECQuestion = 1;
+ // Update the NSEC records again.
+ // TBD: Need to purge and revalidate if the cached NSECS and the new set are not same.
+ if (NSECRecords)
+ {
+ if (!AddNSECSForCacheRecord(m, NSECRecords, neg, rcode))
+ {
+ // We might just have an SOA record for zones that are not signed and hence don't log
+ // this as an error
+ LogInfo("mDNSCoreReceiveNoUnicastAnswers: AddNSECSForCacheRecord failed to add NSEC for negcr %s during refresh", CRDisplayString(m, neg));
+ FreeNSECRecords(m, NSECRecords);
+ neg->CRDNSSECQuestion = 0;
+ }
+ NSECRecords = mDNSNULL;
+ }
+ if (SOARecord)
+ {
+ if (neg->soa)
+ ReleaseCacheRecord(m, neg->soa);
+ neg->soa = SOARecord;
+ SOARecord = mDNSNULL;
+ }
+ }
+ else while (1)
+ {
+ CacheRecord *negcr;
+ debugf("mDNSCoreReceiveNoUnicastAnswers making negative cache entry TTL %d for %##s (%s)", negttl, name->c, DNSTypeName(q.qtype));
+ MakeNegativeCacheRecord(m, &m->rec.r, name, hash, q.qtype, q.qclass, negttl, mDNSInterface_Any, qptr->qDNSServer);
+ m->rec.r.responseFlags = response->h.flags;
+ // We create SOA records above which might create new cache groups. Earlier
+ // in the function we looked up the cache group for the name and it could have
+ // been NULL. If we pass NULL cg to new cache entries that we create below,
+ // it will create additional cache groups for the same name. To avoid that,
+ // look up the cache group again to re-initialize cg again.
+ cg = CacheGroupForName(m, slot, hash, name);
+ if (NSECRecords && DNSSECQuestion(qptr))
+ {
+ // Create the cache entry with delay and then add the NSEC records
+ // to it and add it immediately.
+ negcr = CreateNewCacheEntry(m, slot, cg, 1, mDNStrue, mDNSNULL);
+ if (negcr)
+ {
+ negcr->CRDNSSECQuestion = 0;
+ if (!AddNSECSForCacheRecord(m, NSECRecords, negcr, rcode))
+ {
+ LogInfo("mDNSCoreReceiveNoUnicastAnswers: AddNSECSForCacheRecord failed to add NSEC for negcr %s",
+ CRDisplayString(m, negcr));
+ FreeNSECRecords(m, NSECRecords);
+ }
+ else
+ {
+ negcr->CRDNSSECQuestion = 1;
+ LogInfo("mDNSCoreReceiveNoUnicastAnswers: AddNSECSForCacheRecord added neg NSEC for %s", CRDisplayString(m, negcr));
+ }
+ NSECRecords = mDNSNULL;
+ negcr->DelayDelivery = 0;
+ CacheRecordDeferredAdd(m, negcr);
+ }
+ m->rec.r.resrec.RecordType = 0; // Clear RecordType to show we're not still using it
+ break;
+ }
+ else
+ {
+ // Need to add with a delay so that we can tag the SOA record
+ negcr = CreateNewCacheEntry(m, slot, cg, 1, mDNStrue, mDNSNULL);
+ if (negcr)
+ {
+ negcr->CRDNSSECQuestion = 0;
+ if (DNSSECQuestion(qptr))
+ negcr->CRDNSSECQuestion = 1;
+ negcr->DelayDelivery = 0;
+
+ if (SOARecord)
+ {
+ if (negcr->soa)
+ ReleaseCacheRecord(m, negcr->soa);
+ negcr->soa = SOARecord;
+ SOARecord = mDNSNULL;
+ }
+ CacheRecordDeferredAdd(m, negcr);
+ }
+ }
+ m->rec.r.responseFlags = zeroID;
+ m->rec.r.resrec.RecordType = 0; // Clear RecordType to show we're not still using it
+ if (!repeat) break;
+ repeat--;
+ name = (const domainname *)(name->c + 1 + name->c[0]);
+ hash = DomainNameHashValue(name);
+ slot = HashSlot(name);
+ cg = CacheGroupForName(m, slot, hash, name);
+ }
+ }
+ }
+ }
+ }
+ if (NSECRecords) { LogInfo("mDNSCoreReceiveNoUnicastAnswers: NSECRecords not used"); FreeNSECRecords(m, NSECRecords); }
+ if (SOARecord) { LogInfo("mDNSCoreReceiveNoUnicastAnswers: SOARecord not used"); ReleaseCacheRecord(m, SOARecord); }
+}
+
+mDNSlocal void mDNSCorePrintStoredProxyRecords(mDNS *const m)
+{
+ AuthRecord *rrPtr = mDNSNULL;
+ LogSPS("Stored Proxy records :");
+ for (rrPtr = m->SPSRRSet; rrPtr; rrPtr = rrPtr->next)
+ {
+ LogSPS("%s", ARDisplayString(m, rrPtr));
+ }
+}
+
+mDNSlocal mDNSBool mDNSCoreRegisteredProxyRecord(mDNS *const m, AuthRecord *rr)
+{
+ AuthRecord *rrPtr = mDNSNULL;
+
+ for (rrPtr = m->SPSRRSet; rrPtr; rrPtr = rrPtr->next)
+ {
+ if (IdenticalResourceRecord(&rrPtr->resrec, &rr->resrec))
+ {
+ LogSPS("mDNSCoreRegisteredProxyRecord: Ignoring packet registered with sleep proxy : %s ", ARDisplayString(m, rr));
+ return mDNStrue;
+ }
+ }
+ mDNSCorePrintStoredProxyRecords(m);
+ return mDNSfalse;
+}
+
+mDNSlocal CacheRecord* mDNSCoreReceiveCacheCheck(mDNS *const m, const DNSMessage *const response, uDNS_LLQType LLQType,
+ const mDNSu32 slot, CacheGroup *cg, DNSQuestion *unicastQuestion, CacheRecord ***cfp, CacheRecord **NSECCachePtr,
+ mDNSInterfaceID InterfaceID)
+{
+ CacheRecord *rr;
+ CacheRecord **cflocal = *cfp;
+
+ for (rr = cg ? cg->members : mDNSNULL; rr; rr=rr->next)
+ {
+ mDNSBool match;
+ // Resource record received via unicast, the resGroupID should match ?
+ if (!InterfaceID)
+ {
+ mDNSu16 id1 = (rr->resrec.rDNSServer ? rr->resrec.rDNSServer->resGroupID : 0);
+ mDNSu16 id2 = (m->rec.r.resrec.rDNSServer ? m->rec.r.resrec.rDNSServer->resGroupID : 0);
+ match = (id1 == id2);
+ }
+ else
+ match = (rr->resrec.InterfaceID == InterfaceID);
+ // If we found this exact resource record, refresh its TTL
+ if (match && IdenticalSameNameRecord(&m->rec.r.resrec, &rr->resrec))
+ {
+ if (m->rec.r.resrec.rdlength > InlineCacheRDSize)
+ verbosedebugf("mDNSCoreReceiveCacheCheck: Found record size %5d interface %p already in cache: %s",
+ m->rec.r.resrec.rdlength, InterfaceID, CRDisplayString(m, &m->rec.r));
+
+ if (m->rec.r.resrec.RecordType & kDNSRecordTypePacketUniqueMask)
+ {
+ // If this packet record has the kDNSClass_UniqueRRSet flag set, then add it to our cache flushing list
+ if (rr->NextInCFList == mDNSNULL && *cfp != &rr->NextInCFList && LLQType != uDNS_LLQ_Events)
+ {
+ *cflocal = rr;
+ cflocal = &rr->NextInCFList;
+ *cflocal = (CacheRecord*)1;
+ *cfp = &rr->NextInCFList;
+ }
+
+ // If this packet record is marked unique, and our previous cached copy was not, then fix it
+ if (!(rr->resrec.RecordType & kDNSRecordTypePacketUniqueMask))
+ {
+ DNSQuestion *q;
+ for (q = m->Questions; q; q=q->next)
+ {
+ if (ResourceRecordAnswersQuestion(&rr->resrec, q))
+ q->UniqueAnswers++;
+ }
+ rr->resrec.RecordType = m->rec.r.resrec.RecordType;
+ }
+ }
+
+ if (!SameRDataBody(&m->rec.r.resrec, &rr->resrec.rdata->u, SameDomainNameCS))
+ {
+ // If the rdata of the packet record differs in name capitalization from the record in our cache
+ // then mDNSPlatformMemSame will detect this. In this case, throw the old record away, so that clients get
+ // a 'remove' event for the record with the old capitalization, and then an 'add' event for the new one.
+ // <rdar://problem/4015377> mDNS -F returns the same domain multiple times with different casing
+ rr->resrec.rroriginalttl = 0;
+ rr->TimeRcvd = m->timenow;
+ rr->UnansweredQueries = MaxUnansweredQueries;
+ SetNextCacheCheckTimeForRecord(m, rr);
+ LogInfo("mDNSCoreReceiveCacheCheck: Discarding due to domainname case change old: %s", CRDisplayString(m, rr));
+ LogInfo("mDNSCoreReceiveCacheCheck: Discarding due to domainname case change new: %s", CRDisplayString(m, &m->rec.r));
+ LogInfo("mDNSCoreReceiveCacheCheck: Discarding due to domainname case change in %d slot %3d in %d %d",
+ NextCacheCheckEvent(rr) - m->timenow, slot, m->rrcache_nextcheck[slot] - m->timenow, m->NextCacheCheck - m->timenow);
+ // DO NOT break out here -- we want to continue as if we never found it
+ }
+ else if (!IdenticalAnonInfo(m->rec.r.resrec.AnonInfo, rr->resrec.AnonInfo))
+ {
+ // If the NSEC3 record changed, a few possibilities
+ //
+ // 1) the peer reinitialized e.g., after network change and still part of the
+ // same set.
+ // 2) the peer went to a different set but we did not see the goodbyes. If we just
+ // update the nsec3 record, it would be incorrect. Flush the cache so that we
+ // can deliver a RMV followed by ADD.
+ // 3) if the peer is ourselves and we see the goodbye when moving to a different set
+ // and so we flush the cache and create a new cache record with the new set information.
+ // Now we move back to the original set. In this case, we can't just update the
+ // NSEC3 record alone. We need to flush so that we can deliver an RMV followed by ADD
+ // when we create the new cache entry.
+ //
+ // Note: For case (1), we could avoid flushing the cache but we can't tell the difference
+ // from the other cases.
+ rr->resrec.rroriginalttl = 0;
+ rr->TimeRcvd = m->timenow;
+ rr->UnansweredQueries = MaxUnansweredQueries;
+ SetNextCacheCheckTimeForRecord(m, rr);
+ LogInfo("mDNSCoreReceiveCacheCheck: AnonInfo changed for %s", CRDisplayString(m, rr));
+ // DO NOT break out here -- we want to continue as if we never found it. When we return
+ // from this function, we will create a new cache entry with the new NSEC3 record
+ }
+ else if (m->rec.r.resrec.rroriginalttl > 0)
+ {
+ DNSQuestion *q;
+
+ m->mDNSStats.CacheRefreshed++;
+
+ if (rr->resrec.rroriginalttl == 0) debugf("uDNS rescuing %s", CRDisplayString(m, rr));
+ RefreshCacheRecord(m, rr, m->rec.r.resrec.rroriginalttl);
+ rr->responseFlags = response->h.flags;
+
+ // If we may have NSEC records returned with the answer (which we don't know yet as it
+ // has not been processed), we need to cache them along with the first cache
+ // record in the list that answers the question so that it can be used for validation
+ // later. The "type" check below is to make sure that we cache on the cache record
+ // that would answer the question. It is possible that we might cache additional things
+ // e.g., MX question might cache A records also, and we want to cache the NSEC on
+ // the record that answers the question.
+ if (response->h.numAnswers && unicastQuestion && unicastQuestion->qtype == rr->resrec.rrtype
+ && !(*NSECCachePtr))
+ {
+ LogInfo("mDNSCoreReceiveCacheCheck: rescuing RR %s", CRDisplayString(m, rr));
+ *NSECCachePtr = rr;
+ }
+ // We have to reset the question interval to MaxQuestionInterval so that we don't keep
+ // polling the network once we get a valid response back. For the first time when a new
+ // cache entry is created, AnswerCurrentQuestionWithResourceRecord does that.
+ // Subsequently, if we reissue questions from within the mDNSResponder e.g., DNS server
+ // configuration changed, without flushing the cache, we reset the question interval here.
+ // Currently, we do this for for both multicast and unicast questions as long as the record
+ // type is unique. For unicast, resource record is always unique and for multicast it is
+ // true for records like A etc. but not for PTR.
+ if (rr->resrec.RecordType & kDNSRecordTypePacketUniqueMask)
+ {
+ for (q = m->Questions; q; q=q->next)
+ {
+ if (!q->DuplicateOf && !q->LongLived &&
+ ActiveQuestion(q) && ResourceRecordAnswersQuestion(&rr->resrec, q))
+ {
+ ResetQuestionState(m, q);
+ debugf("mDNSCoreReceiveCacheCheck: Set MaxQuestionInterval for %p %##s (%s)", q, q->qname.c, DNSTypeName(q->qtype));
+ break; // Why break here? Aren't there other questions we might want to look at?-- SC July 2010
+ }
+ }
+ }
+ break;
+ }
+ else
+ {
+
+ // If the packet TTL is zero, that means we're deleting this record.
+ // To give other hosts on the network a chance to protest, we push the deletion
+ // out one second into the future. Also, we set UnansweredQueries to MaxUnansweredQueries.
+ // Otherwise, we'll do final queries for this record at 80% and 90% of its apparent
+ // lifetime (800ms and 900ms from now) which is a pointless waste of network bandwidth.
+ // If record's current expiry time is more than a second from now, we set it to expire in one second.
+ // If the record is already going to expire in less than one second anyway, we leave it alone --
+ // we don't want to let the goodbye packet *extend* the record's lifetime in our cache.
+ debugf("DE for %s", CRDisplayString(m, rr));
+ if (RRExpireTime(rr) - m->timenow > mDNSPlatformOneSecond)
+ {
+ rr->resrec.rroriginalttl = 1;
+ rr->TimeRcvd = m->timenow;
+ rr->UnansweredQueries = MaxUnansweredQueries;
+ SetNextCacheCheckTimeForRecord(m, rr);
+ }
+ break;
+ }
+ }
+ }
+ return rr;
+}
+
+mDNSlocal void mDNSParseNSEC3Records(mDNS *const m, const DNSMessage *const response, const mDNSu8 *end,
+ const mDNSInterfaceID InterfaceID, CacheRecord **NSEC3Records)
+{
+ const mDNSu8 *ptr = response->data;
+ CacheRecord *rr;
+ int i;
+
+ if (!response->h.numAuthorities)
+ return;
+ ptr = LocateAuthorities(response, end);
+ if (!ptr)
+ {
+ LogInfo("mDNSParseNSEC3Records: ERROR can't locate authorities");
+ return;
+ }
+ for (i = 0; i < response->h.numAuthorities && ptr && ptr < end; i++)
+ {
+ mDNSu32 slot;
+ CacheGroup *cg;
+
+ ptr = GetLargeResourceRecord(m, response, ptr, end, InterfaceID, kDNSRecordTypePacketAuth, &m->rec);
+ if (!ptr || m->rec.r.resrec.RecordType == kDNSRecordTypePacketNegative || m->rec.r.resrec.rrtype != kDNSType_NSEC3)
+ {
+ debugf("mDNSParseNSEC3Records: ptr %p, Record %s, ignoring", ptr, CRDisplayString(m, &m->rec.r));
+ m->rec.r.resrec.RecordType = 0;
+ continue;
+ }
+ slot = HashSlot(m->rec.r.resrec.name);
+ cg = CacheGroupForRecord(m, slot, &m->rec.r.resrec);
+ // Create the cache entry but don't add it to the cache it. We need
+ // to cache this along with the main cache record.
+ rr = CreateNewCacheEntry(m, slot, cg, 0, mDNSfalse, mDNSNULL);
+ if (rr)
+ {
+ debugf("mDNSParseNSEC3Records: %s", CRDisplayString(m, rr));
+ *NSEC3Records = rr;
+ NSEC3Records = &rr->next;
+ }
+ m->rec.r.resrec.RecordType = 0; // Clear RecordType to show we're not still using it
+ }
+}
+
+mDNSlocal void mDNSCoreResetRecord(mDNS *const m)
+{
+ m->rec.r.resrec.RecordType = 0; // Clear RecordType to show we're not still using it
+ if (m->rec.r.resrec.AnonInfo)
+ {
+ FreeAnonInfo(m->rec.r.resrec.AnonInfo);
+ m->rec.r.resrec.AnonInfo = mDNSNULL;
+ }
+}
+
+#define DEVICE_INFO_RECORD_LABELS 4
+
+// Determine if the record is an instance of _device-info._tcp.local.
+mDNSlocal mDNSBool IsDeviceInfoRecord(const domainname *d)
+{
+ const domainname *afterInstance;
+
+ if (CountLabels(d) != DEVICE_INFO_RECORD_LABELS)
+ return mDNSfalse;
+
+ // skip the instance name
+ afterInstance = SkipLeadingLabels(d, 1);
+ if (SameDomainName(afterInstance, &LocalDeviceInfoName))
+ return mDNStrue;
+
+ return mDNSfalse;
+}
// Note: mDNSCoreReceiveResponse calls mDNS_Deregister_internal which can call a user callback, which may change
// the record list and/or question list.
// InterfaceID NULL tells us this was a unicast response
// dstaddr NULL tells us we received this over an outgoing TCP connection we made
mDNSlocal void mDNSCoreReceiveResponse(mDNS *const m,
- const DNSMessage *const response, const mDNSu8 *end,
- const mDNSAddr *srcaddr, const mDNSIPPort srcport, const mDNSAddr *dstaddr, mDNSIPPort dstport,
- const mDNSInterfaceID InterfaceID)
- {
- int i;
- mDNSBool ResponseMCast = dstaddr && mDNSAddrIsDNSMulticast(dstaddr);
- mDNSBool ResponseSrcLocal = !srcaddr || mDNS_AddressIsLocalSubnet(m, InterfaceID, srcaddr);
- DNSQuestion *llqMatch = mDNSNULL;
- uDNS_LLQType LLQType = uDNS_recvLLQResponse(m, response, end, srcaddr, srcport, &llqMatch);
-
- // "(CacheRecord*)1" is a special (non-zero) end-of-list marker
- // We use this non-zero marker so that records in our CacheFlushRecords list will always have NextInCFList
- // set non-zero, and that tells GetCacheEntity() that they're not, at this moment, eligible for recycling.
- CacheRecord *CacheFlushRecords = (CacheRecord*)1;
- CacheRecord **cfp = &CacheFlushRecords;
-
- // All records in a DNS response packet are treated as equally valid statements of truth. If we want
- // to guard against spoof responses, then the only credible protection against that is cryptographic
- // security, e.g. DNSSEC., not worring about which section in the spoof packet contained the record
- int firstauthority = response->h.numAnswers;
- int firstadditional = firstauthority + response->h.numAuthorities;
- int totalrecords = firstadditional + response->h.numAdditionals;
- const mDNSu8 *ptr = response->data;
- DNSServer *uDNSServer = mDNSNULL;
-
- debugf("Received Response from %#-15a addressed to %#-15a on %p with "
- "%2d Question%s %2d Answer%s %2d Authorit%s %2d Additional%s %d bytes LLQType %d",
- srcaddr, dstaddr, InterfaceID,
- response->h.numQuestions, response->h.numQuestions == 1 ? ", " : "s,",
- response->h.numAnswers, response->h.numAnswers == 1 ? ", " : "s,",
- response->h.numAuthorities, response->h.numAuthorities == 1 ? "y, " : "ies,",
- response->h.numAdditionals, response->h.numAdditionals == 1 ? " " : "s", end - response->data, LLQType);
-
- // According to RFC 2181 <http://www.ietf.org/rfc/rfc2181.txt>
- // When a DNS client receives a reply with TC
- // set, it should ignore that response, and query again, using a
- // mechanism, such as a TCP connection, that will permit larger replies.
- // It feels wrong to be throwing away data after the network went to all the trouble of delivering it to us, but
- // delivering some records of the RRSet first and then the remainder a couple of milliseconds later was causing
- // failures in our Microsoft Active Directory client, which expects to get the entire set of answers at once.
- // <rdar://problem/6690034> Can't bind to Active Directory
- // In addition, if the client immediately canceled its query after getting the initial partial response, then we'll
- // abort our TCP connection, and not complete the operation, and end up with an incomplete RRSet in our cache.
- // Next time there's a query for this RRSet we'll see answers in our cache, and assume we have the whole RRSet already,
- // and not even do the TCP query.
- // Accordingly, if we get a uDNS reply with kDNSFlag0_TC set, we bail out and wait for the TCP response containing the entire RRSet.
- if (!InterfaceID && (response->h.flags.b[0] & kDNSFlag0_TC)) return;
-
- if (LLQType == uDNS_LLQ_Ignore) return;
-
- // 1. We ignore questions (if any) in mDNS response packets
- // 2. If this is an LLQ response, we handle it much the same
- // 3. If we get a uDNS UDP response with the TC (truncated) bit set, then we can't treat this
- // answer as being the authoritative complete RRSet, and respond by deleting all other
- // matching cache records that don't appear in this packet.
- // Otherwise, this is a authoritative uDNS answer, so arrange for any stale records to be purged
- if (ResponseMCast || LLQType == uDNS_LLQ_Events || (response->h.flags.b[0] & kDNSFlag0_TC))
- ptr = LocateAnswers(response, end);
- // Otherwise, for one-shot queries, any answers in our cache that are not also contained
- // in this response packet are immediately deemed to be invalid.
- else
- {
- mDNSu8 rcode = (mDNSu8)(response->h.flags.b[1] & kDNSFlag1_RC_Mask);
- mDNSBool failure = !(rcode == kDNSFlag1_RC_NoErr || rcode == kDNSFlag1_RC_NXDomain || rcode == kDNSFlag1_RC_NotAuth);
- mDNSBool returnEarly = mDNSfalse;
- // We could possibly combine this with the similar loop at the end of this function --
- // instead of tagging cache records here and then rescuing them if we find them in the answer section,
- // we could instead use the "m->PktNum" mechanism to tag each cache record with the packet number in
- // which it was received (or refreshed), and then at the end if we find any cache records which
- // answer questions in this packet's question section, but which aren't tagged with this packet's
- // packet number, then we deduce they are old and delete them
- for (i = 0; i < response->h.numQuestions && ptr && ptr < end; i++)
- {
- DNSQuestion q, *qptr = mDNSNULL;
- ptr = getQuestion(response, ptr, end, InterfaceID, &q);
- if (ptr && (qptr = ExpectingUnicastResponseForQuestion(m, dstport, response->h.id, &q, !dstaddr)))
- {
- if (!failure)
- {
- CacheRecord *rr;
- const mDNSu32 slot = HashSlot(&q.qname);
- CacheGroup *cg = CacheGroupForName(m, slot, q.qnamehash, &q.qname);
- for (rr = cg ? cg->members : mDNSNULL; rr; rr=rr->next)
- if (SameNameRecordAnswersQuestion(&rr->resrec, qptr))
- {
- debugf("uDNS marking %p %##s (%s) %p %s", q.InterfaceID, q.qname.c, DNSTypeName(q.qtype),
- rr->resrec.InterfaceID, CRDisplayString(m, rr));
- // Don't want to disturb rroriginalttl here, because code below might need it for the exponential backoff doubling algorithm
- rr->TimeRcvd = m->timenow - TicksTTL(rr) - 1;
- rr->UnansweredQueries = MaxUnansweredQueries;
- }
- }
- else
- {
- if (qptr)
- {
- LogInfo("mDNSCoreReceiveResponse: Server %p responded with code %d to query %##s (%s)", qptr->qDNSServer, rcode, q.qname.c, DNSTypeName(q.qtype));
- PenalizeDNSServer(m, qptr);
- }
- returnEarly = mDNStrue;
- }
- }
- }
- if (returnEarly)
- {
- LogInfo("Ignoring %2d Answer%s %2d Authorit%s %2d Additional%s",
- response->h.numAnswers, response->h.numAnswers == 1 ? ", " : "s,",
- response->h.numAuthorities, response->h.numAuthorities == 1 ? "y, " : "ies,",
- response->h.numAdditionals, response->h.numAdditionals == 1 ? "" : "s");
- // not goto exit because we won't have any CacheFlushRecords and we do not want to
- // generate negative cache entries (we want to query the next server)
- return;
- }
- }
-
- for (i = 0; i < totalrecords && ptr && ptr < end; i++)
- {
- // All responses sent via LL multicast are acceptable for caching
- // All responses received over our outbound TCP connections are acceptable for caching
- mDNSBool AcceptableResponse = ResponseMCast || !dstaddr || LLQType;
- // (Note that just because we are willing to cache something, that doesn't necessarily make it a trustworthy answer
- // to any specific question -- any code reading records from the cache needs to make that determination for itself.)
-
- const mDNSu8 RecordType =
- (i < firstauthority ) ? (mDNSu8)kDNSRecordTypePacketAns :
- (i < firstadditional) ? (mDNSu8)kDNSRecordTypePacketAuth : (mDNSu8)kDNSRecordTypePacketAdd;
- ptr = GetLargeResourceRecord(m, response, ptr, end, InterfaceID, RecordType, &m->rec);
- if (!ptr) goto exit; // Break out of the loop and clean up our CacheFlushRecords list before exiting
- if (m->rec.r.resrec.RecordType == kDNSRecordTypePacketNegative) { m->rec.r.resrec.RecordType = 0; continue; }
-
- // Don't want to cache OPT or TSIG pseudo-RRs
- if (m->rec.r.resrec.rrtype == kDNSType_TSIG) { m->rec.r.resrec.RecordType = 0; continue; }
- if (m->rec.r.resrec.rrtype == kDNSType_OPT)
- {
- const rdataOPT *opt;
- const rdataOPT *const e = (const rdataOPT *)&m->rec.r.resrec.rdata->u.data[m->rec.r.resrec.rdlength];
- // Find owner sub-option(s). We verify that the MAC is non-zero, otherwise we could inadvertently
- // delete all our own AuthRecords (which are identified by having zero MAC tags on them).
- for (opt = &m->rec.r.resrec.rdata->u.opt[0]; opt < e; opt++)
- if (opt->opt == kDNSOpt_Owner && opt->u.owner.vers == 0 && opt->u.owner.HMAC.l[0])
- {
- ClearProxyRecords(m, &opt->u.owner, m->DuplicateRecords);
- ClearProxyRecords(m, &opt->u.owner, m->ResourceRecords);
- }
- m->rec.r.resrec.RecordType = 0;
- continue;
- }
-
- // if a CNAME record points to itself, then don't add it to the cache
- if ((m->rec.r.resrec.rrtype == kDNSType_CNAME) && SameDomainName(m->rec.r.resrec.name, &m->rec.r.resrec.rdata->u.name))
- {
- LogInfo("mDNSCoreReceiveResponse: CNAME loop domain name %##s", m->rec.r.resrec.name->c);
- m->rec.r.resrec.RecordType = 0;
- continue;
- }
-
- // When we receive uDNS LLQ responses, we assume a long cache lifetime --
- // In the case of active LLQs, we'll get remove events when the records actually do go away
- // In the case of polling LLQs, we assume the record remains valid until the next poll
- if (!mDNSOpaque16IsZero(response->h.id))
- m->rec.r.resrec.rroriginalttl = GetEffectiveTTL(LLQType, m->rec.r.resrec.rroriginalttl);
-
- // If response was not sent via LL multicast,
- // then see if it answers a recent query of ours, which would also make it acceptable for caching.
- if (!ResponseMCast)
- {
- if (LLQType)
- {
- // For Long Lived queries that are both sent over UDP and Private TCP, LLQType is set.
- // Even though it is AcceptableResponse, we need a matching DNSServer pointer for the
- // queries to get ADD/RMV events. To lookup the question, we can't use
- // ExpectingUnicastResponseForRecord as the port numbers don't match. uDNS_recvLLQRespose
- // has already matched the question using the 64 bit Id in the packet and we use that here.
-
- if (llqMatch != mDNSNULL) m->rec.r.resrec.rDNSServer = uDNSServer = llqMatch->qDNSServer;
- }
- else if (!AcceptableResponse || !dstaddr)
- {
- // For responses that come over TCP (Responses that can't fit within UDP) or TLS (Private queries
- // that are not long lived e.g., AAAA lookup in a Private domain), it is indicated by !dstaddr.
- // Even though it is AcceptableResponse, we still need a DNSServer pointer for the resource records that
- // we create.
-
- DNSQuestion *q = ExpectingUnicastResponseForRecord(m, srcaddr, ResponseSrcLocal, dstport, response->h.id, &m->rec.r, !dstaddr);
-
- // Intialize the DNS server on the resource record which will now filter what questions we answer with
- // this record.
- //
- // We could potentially lookup the DNS server based on the source address, but that may not work always
- // and that's why ExpectingUnicastResponseForRecord does not try to verify whether the response came
- // from the DNS server that queried. We follow the same logic here. If we can find a matching quetion based
- // on the "id" and "source port", then this response answers the question and assume the response
- // came from the same DNS server that we sent the query to.
-
- if (q != mDNSNULL)
- {
- AcceptableResponse = mDNStrue;
- if (!InterfaceID)
- {
- debugf("mDNSCoreReceiveResponse: InterfaceID %p %##s (%s)", q->InterfaceID, q->qname.c, DNSTypeName(q->qtype));
- m->rec.r.resrec.rDNSServer = uDNSServer = q->qDNSServer;
- }
- }
- else
- {
- // If we can't find a matching question, we need to see whether we have seen records earlier that matched
- // the question. The code below does that. So, make this record unacceptable for now
- if (!InterfaceID)
- {
- debugf("mDNSCoreReceiveResponse: Can't find question for record name %##s", m->rec.r.resrec.name->c);
- AcceptableResponse = mDNSfalse;
- }
- }
- }
- }
-
- // 1. Check that this packet resource record does not conflict with any of ours
- if (mDNSOpaque16IsZero(response->h.id) && m->rec.r.resrec.rrtype != kDNSType_NSEC)
- {
- if (m->CurrentRecord)
- LogMsg("mDNSCoreReceiveResponse ERROR m->CurrentRecord already set %s", ARDisplayString(m, m->CurrentRecord));
- m->CurrentRecord = m->ResourceRecords;
- while (m->CurrentRecord)
- {
- AuthRecord *rr = m->CurrentRecord;
- m->CurrentRecord = rr->next;
- // We accept all multicast responses, and unicast responses resulting from queries we issued
- // For other unicast responses, this code accepts them only for responses with an
- // (apparently) local source address that pertain to a record of our own that's in probing state
- if (!AcceptableResponse && !(ResponseSrcLocal && rr->resrec.RecordType == kDNSRecordTypeUnique)) continue;
-
- if (PacketRRMatchesSignature(&m->rec.r, rr)) // If interface, name, type (if shared record) and class match...
- {
- // ... check to see if type and rdata are identical
- if (IdenticalSameNameRecord(&m->rec.r.resrec, &rr->resrec))
- {
- // If the RR in the packet is identical to ours, just check they're not trying to lower the TTL on us
- if (m->rec.r.resrec.rroriginalttl >= rr->resrec.rroriginalttl/2 || m->SleepState)
- {
- // If we were planning to send on this -- and only this -- interface, then we don't need to any more
- if (rr->ImmedAnswer == InterfaceID) { rr->ImmedAnswer = mDNSNULL; rr->ImmedUnicast = mDNSfalse; }
- }
- else
- {
- if (rr->ImmedAnswer == mDNSNULL) { rr->ImmedAnswer = InterfaceID; m->NextScheduledResponse = m->timenow; }
- else if (rr->ImmedAnswer != InterfaceID) { rr->ImmedAnswer = mDNSInterfaceMark; m->NextScheduledResponse = m->timenow; }
- }
- }
- // else, the packet RR has different type or different rdata -- check to see if this is a conflict
- else if (m->rec.r.resrec.rroriginalttl > 0 && PacketRRConflict(m, rr, &m->rec.r))
- {
- LogInfo("mDNSCoreReceiveResponse: Pkt Record: %08lX %s", m->rec.r.resrec.rdatahash, CRDisplayString(m, &m->rec.r));
- LogInfo("mDNSCoreReceiveResponse: Our Record: %08lX %s", rr-> resrec.rdatahash, ARDisplayString(m, rr));
-
- // If this record is marked DependentOn another record for conflict detection purposes,
- // then *that* record has to be bumped back to probing state to resolve the conflict
- if (rr->DependentOn)
- {
- while (rr->DependentOn) rr = rr->DependentOn;
- LogInfo("mDNSCoreReceiveResponse: Dep Record: %08lX %s", rr-> resrec.rdatahash, ARDisplayString(m, rr));
- }
-
- // If we've just whacked this record's ProbeCount, don't need to do it again
- if (rr->ProbeCount > DefaultProbeCountForTypeUnique)
- LogInfo("mDNSCoreReceiveResponse: Already reset to Probing: %s", ARDisplayString(m, rr));
- else if (rr->ProbeCount == DefaultProbeCountForTypeUnique)
- LogMsg("mDNSCoreReceiveResponse: Ignoring response received before we even began probing: %s", ARDisplayString(m, rr));
- else
- {
- LogMsg("mDNSCoreReceiveResponse: Received from %#a:%d %s", srcaddr, mDNSVal16(srcport), CRDisplayString(m, &m->rec.r));
- // If we'd previously verified this record, put it back to probing state and try again
- if (rr->resrec.RecordType == kDNSRecordTypeVerified)
- {
- LogMsg("mDNSCoreReceiveResponse: Resetting to Probing: %s", ARDisplayString(m, rr));
- rr->resrec.RecordType = kDNSRecordTypeUnique;
- // We set ProbeCount to one more than the usual value so we know we've already touched this record.
- // This is because our single probe for "example-name.local" could yield a response with (say) two A records and
- // three AAAA records in it, and we don't want to call RecordProbeFailure() five times and count that as five conflicts.
- // This special value is recognised and reset to DefaultProbeCountForTypeUnique in SendQueries().
- rr->ProbeCount = DefaultProbeCountForTypeUnique + 1;
- rr->AnnounceCount = InitialAnnounceCount;
- InitializeLastAPTime(m, rr);
- RecordProbeFailure(m, rr); // Repeated late conflicts also cause us to back off to the slower probing rate
- }
- // If we're probing for this record, we just failed
- else if (rr->resrec.RecordType == kDNSRecordTypeUnique)
- {
- LogMsg("mDNSCoreReceiveResponse: ProbeCount %d; will deregister %s", rr->ProbeCount, ARDisplayString(m, rr));
- mDNS_Deregister_internal(m, rr, mDNS_Dereg_conflict);
- }
- // We assumed this record must be unique, but we were wrong. (e.g. There are two mDNSResponders on the
- // same machine giving different answers for the reverse mapping record, or there are two machines on the
- // network using the same IP address.) This is simply a misconfiguration, and there's nothing we can do
- // to fix it -- e.g. it's not our job to be trying to change the machine's IP address. We just discard our
- // record to avoid continued conflicts (as we do for a conflict on our Unique records) and get on with life.
- else if (rr->resrec.RecordType == kDNSRecordTypeKnownUnique)
- {
- LogMsg("mDNSCoreReceiveResponse: Unexpected conflict discarding %s", ARDisplayString(m, rr));
- mDNS_Deregister_internal(m, rr, mDNS_Dereg_conflict);
- }
- else
- LogMsg("mDNSCoreReceiveResponse: Unexpected record type %X %s", rr->resrec.RecordType, ARDisplayString(m, rr));
- }
- }
- // Else, matching signature, different type or rdata, but not a considered a conflict.
- // If the packet record has the cache-flush bit set, then we check to see if we
- // have any record(s) of the same type that we should re-assert to rescue them
- // (see note about "multi-homing and bridged networks" at the end of this function).
- else if (m->rec.r.resrec.rrtype == rr->resrec.rrtype)
- if ((m->rec.r.resrec.RecordType & kDNSRecordTypePacketUniqueMask) && m->timenow - rr->LastMCTime > mDNSPlatformOneSecond/2)
- { rr->ImmedAnswer = mDNSInterfaceMark; m->NextScheduledResponse = m->timenow; }
- }
- }
- }
-
- if (!AcceptableResponse)
- {
- const CacheRecord *cr;
- for (cr = CacheFlushRecords; cr != (CacheRecord*)1; cr = cr->NextInCFList)
- {
- domainname *target = GetRRDomainNameTarget(&cr->resrec);
- // When we issue a query for A record, the response might contain both a CNAME and A records. Only the CNAME would
- // match the question and we already created a cache entry in the previous pass of this loop. Now when we process
- // the A record, it does not match the question because the record name here is the CNAME. Hence we try to
- // match with the previous records to make it an AcceptableResponse. We have to be careful about setting the
- // DNSServer value that we got in the previous pass. This can happen for other record types like SRV also.
-
- if (target && cr->resrec.rdatahash == m->rec.r.resrec.namehash && SameDomainName(target, m->rec.r.resrec.name))
- {
- debugf("mDNSCoreReceiveResponse: Found a matching entry for %##s in the CacheFlushRecords", m->rec.r.resrec.name->c);
- AcceptableResponse = mDNStrue;
- m->rec.r.resrec.rDNSServer = uDNSServer;
- break;
- }
- }
- }
-
- // 2. See if we want to add this packet resource record to our cache
- // We only try to cache answers if we have a cache to put them in
- // Also, we ignore any apparent attempts at cache poisoning unicast to us that do not answer any outstanding active query
- if (!AcceptableResponse) LogInfo("mDNSCoreReceiveResponse ignoring %s", CRDisplayString(m, &m->rec.r));
- if (m->rrcache_size && AcceptableResponse)
- {
- const mDNSu32 slot = HashSlot(m->rec.r.resrec.name);
- CacheGroup *cg = CacheGroupForRecord(m, slot, &m->rec.r.resrec);
- CacheRecord *rr;
-
- // 2a. Check if this packet resource record is already in our cache
- for (rr = cg ? cg->members : mDNSNULL; rr; rr=rr->next)
- {
- mDNSBool match = !InterfaceID ? m->rec.r.resrec.rDNSServer == rr->resrec.rDNSServer : rr->resrec.InterfaceID == InterfaceID;
- // If we found this exact resource record, refresh its TTL
- if (match && IdenticalSameNameRecord(&m->rec.r.resrec, &rr->resrec))
- {
- if (m->rec.r.resrec.rdlength > InlineCacheRDSize)
- verbosedebugf("Found record size %5d interface %p already in cache: %s",
- m->rec.r.resrec.rdlength, InterfaceID, CRDisplayString(m, &m->rec.r));
-
- if (m->rec.r.resrec.RecordType & kDNSRecordTypePacketUniqueMask)
- {
- // If this packet record has the kDNSClass_UniqueRRSet flag set, then add it to our cache flushing list
- if (rr->NextInCFList == mDNSNULL && cfp != &rr->NextInCFList && LLQType != uDNS_LLQ_Events)
- { *cfp = rr; cfp = &rr->NextInCFList; *cfp = (CacheRecord*)1; }
-
- // If this packet record is marked unique, and our previous cached copy was not, then fix it
- if (!(rr->resrec.RecordType & kDNSRecordTypePacketUniqueMask))
- {
- DNSQuestion *q;
- for (q = m->Questions; q; q=q->next) if (ResourceRecordAnswersQuestion(&rr->resrec, q)) q->UniqueAnswers++;
- rr->resrec.RecordType = m->rec.r.resrec.RecordType;
- }
- }
-
- if (!SameRDataBody(&m->rec.r.resrec, &rr->resrec.rdata->u, SameDomainNameCS))
- {
- // If the rdata of the packet record differs in name capitalization from the record in our cache
- // then mDNSPlatformMemSame will detect this. In this case, throw the old record away, so that clients get
- // a 'remove' event for the record with the old capitalization, and then an 'add' event for the new one.
- // <rdar://problem/4015377> mDNS -F returns the same domain multiple times with different casing
- rr->resrec.rroriginalttl = 0;
- rr->TimeRcvd = m->timenow;
- rr->UnansweredQueries = MaxUnansweredQueries;
- SetNextCacheCheckTimeForRecord(m, rr);
- LogInfo("Discarding due to domainname case change old: %s", CRDisplayString(m,rr));
- LogInfo("Discarding due to domainname case change new: %s", CRDisplayString(m,&m->rec.r));
- LogInfo("Discarding due to domainname case change in %d slot %3d in %d %d",
- NextCacheCheckEvent(rr) - m->timenow, slot, m->rrcache_nextcheck[slot] - m->timenow, m->NextCacheCheck - m->timenow);
- // DO NOT break out here -- we want to continue as if we never found it
- }
- else if (m->rec.r.resrec.rroriginalttl > 0)
- {
- DNSQuestion *q;
- //if (rr->resrec.rroriginalttl == 0) LogMsg("uDNS rescuing %s", CRDisplayString(m, rr));
- RefreshCacheRecord(m, rr, m->rec.r.resrec.rroriginalttl);
-
- // We have to reset the question interval to MaxQuestionInterval so that we don't keep
- // polling the network once we get a valid response back. For the first time when a new
- // cache entry is created, AnswerCurrentQuestionWithResourceRecord does that.
- // Subsequently, if we reissue questions from within the mDNSResponder e.g., DNS server
- // configuration changed, without flushing the cache, we reset the question interval here.
- // Currently, we do this for for both multicast and unicast questions as long as the record
- // type is unique. For unicast, resource record is always unique and for multicast it is
- // true for records like A etc. but not for PTR.
- if (rr->resrec.RecordType & kDNSRecordTypePacketUniqueMask)
- {
- for (q = m->Questions; q; q=q->next)
- {
- if (!q->DuplicateOf && !q->LongLived &&
- ActiveQuestion(q) && ResourceRecordAnswersQuestion(&rr->resrec, q))
- {
- q->LastQTime = m->timenow;
- q->LastQTxTime = m->timenow;
- q->RecentAnswerPkts = 0;
- q->ThisQInterval = MaxQuestionInterval;
- q->RequestUnicast = mDNSfalse;
- q->unansweredQueries = 0;
- debugf("mDNSCoreReceiveResponse: Set MaxQuestionInterval for %p %##s (%s)", q, q->qname.c, DNSTypeName(q->qtype));
- break; // Why break here? Aren't there other questions we might want to look at?-- SC July 2010
- }
- }
- }
- break;
- }
- else
- {
- // If the packet TTL is zero, that means we're deleting this record.
- // To give other hosts on the network a chance to protest, we push the deletion
- // out one second into the future. Also, we set UnansweredQueries to MaxUnansweredQueries.
- // Otherwise, we'll do final queries for this record at 80% and 90% of its apparent
- // lifetime (800ms and 900ms from now) which is a pointless waste of network bandwidth.
- // If record's current expiry time is more than a second from now, we set it to expire in one second.
- // If the record is already going to expire in less than one second anyway, we leave it alone --
- // we don't want to let the goodbye packet *extend* the record's lifetime in our cache.
- debugf("DE for %s", CRDisplayString(m, rr));
- if (RRExpireTime(rr) - m->timenow > mDNSPlatformOneSecond)
- {
- rr->resrec.rroriginalttl = 1;
- rr->TimeRcvd = m->timenow;
- rr->UnansweredQueries = MaxUnansweredQueries;
- SetNextCacheCheckTimeForRecord(m, rr);
- }
- break;
- }
- }
- }
-
- // If packet resource record not in our cache, add it now
- // (unless it is just a deletion of a record we never had, in which case we don't care)
- if (!rr && m->rec.r.resrec.rroriginalttl > 0)
- {
- const mDNSBool AddToCFList = (m->rec.r.resrec.RecordType & kDNSRecordTypePacketUniqueMask) && (LLQType != uDNS_LLQ_Events);
- const mDNSs32 delay = AddToCFList ? NonZeroTime(m->timenow + mDNSPlatformOneSecond) :
- CheckForSoonToExpireRecords(m, m->rec.r.resrec.name, m->rec.r.resrec.namehash, slot);
- // If unique, assume we may have to delay delivery of this 'add' event.
- // Below, where we walk the CacheFlushRecords list, we either call CacheRecordDeferredAdd()
- // to immediately to generate answer callbacks, or we call ScheduleNextCacheCheckTime()
- // to schedule an mDNS_Execute task at the appropriate time.
- rr = CreateNewCacheEntry(m, slot, cg, delay);
- if (rr)
- {
- if (AddToCFList) { *cfp = rr; cfp = &rr->NextInCFList; *cfp = (CacheRecord*)1; }
- else if (rr->DelayDelivery) ScheduleNextCacheCheckTime(m, slot, rr->DelayDelivery);
- }
- }
- }
- m->rec.r.resrec.RecordType = 0; // Clear RecordType to show we're not still using it
- }
+ const DNSMessage *const response, const mDNSu8 *end,
+ const mDNSAddr *srcaddr, const mDNSIPPort srcport, const mDNSAddr *dstaddr, mDNSIPPort dstport,
+ const mDNSInterfaceID InterfaceID)
+{
+ int i;
+ mDNSBool myself;
+ mDNSBool ResponseMCast = dstaddr && mDNSAddrIsDNSMulticast(dstaddr);
+ mDNSBool ResponseSrcLocal = !srcaddr || mDNS_AddressIsLocalSubnet(m, InterfaceID, srcaddr, &myself);
+ DNSQuestion *llqMatch = mDNSNULL;
+ DNSQuestion *unicastQuestion = mDNSNULL;
+ uDNS_LLQType LLQType = uDNS_recvLLQResponse(m, response, end, srcaddr, srcport, &llqMatch);
+
+ // "(CacheRecord*)1" is a special (non-zero) end-of-list marker
+ // We use this non-zero marker so that records in our CacheFlushRecords list will always have NextInCFList
+ // set non-zero, and that tells GetCacheEntity() that they're not, at this moment, eligible for recycling.
+ CacheRecord *CacheFlushRecords = (CacheRecord*)1;
+ CacheRecord **cfp = &CacheFlushRecords;
+ CacheRecord *NSECRecords = mDNSNULL;
+ CacheRecord *NSECCachePtr = mDNSNULL;
+ CacheRecord **nsecp = &NSECRecords;
+ CacheRecord *McastNSEC3Records = mDNSNULL;
+ mDNSBool nseclist;
+ mDNSu8 rcode = '\0';
+ mDNSBool rrsigsCreated = mDNSfalse;
+ mDNSBool DNSSECQuestion = mDNSfalse;
+ mDNSBool recordAccepted = mDNSfalse;
+ NetworkInterfaceInfo *llintf = FirstIPv4LLInterfaceForID(m, InterfaceID);
+
+ // All records in a DNS response packet are treated as equally valid statements of truth. If we want
+ // to guard against spoof responses, then the only credible protection against that is cryptographic
+ // security, e.g. DNSSEC., not worring about which section in the spoof packet contained the record
+ int firstauthority = response->h.numAnswers;
+ int firstadditional = firstauthority + response->h.numAuthorities;
+ int totalrecords = firstadditional + response->h.numAdditionals;
+ const mDNSu8 *ptr = response->data;
+ DNSServer *uDNSServer = mDNSNULL;
+
+ debugf("Received Response from %#-15a addressed to %#-15a on %p with "
+ "%2d Question%s %2d Answer%s %2d Authorit%s %2d Additional%s %d bytes LLQType %d",
+ srcaddr, dstaddr, InterfaceID,
+ response->h.numQuestions, response->h.numQuestions == 1 ? ", " : "s,",
+ response->h.numAnswers, response->h.numAnswers == 1 ? ", " : "s,",
+ response->h.numAuthorities, response->h.numAuthorities == 1 ? "y, " : "ies,",
+ response->h.numAdditionals, response->h.numAdditionals == 1 ? " " : "s", end - response->data, LLQType);
+
+ // According to RFC 2181 <http://www.ietf.org/rfc/rfc2181.txt>
+ // When a DNS client receives a reply with TC
+ // set, it should ignore that response, and query again, using a
+ // mechanism, such as a TCP connection, that will permit larger replies.
+ // It feels wrong to be throwing away data after the network went to all the trouble of delivering it to us, but
+ // delivering some records of the RRSet first and then the remainder a couple of milliseconds later was causing
+ // failures in our Microsoft Active Directory client, which expects to get the entire set of answers at once.
+ // <rdar://problem/6690034> Can't bind to Active Directory
+ // In addition, if the client immediately canceled its query after getting the initial partial response, then we'll
+ // abort our TCP connection, and not complete the operation, and end up with an incomplete RRSet in our cache.
+ // Next time there's a query for this RRSet we'll see answers in our cache, and assume we have the whole RRSet already,
+ // and not even do the TCP query.
+ // Accordingly, if we get a uDNS reply with kDNSFlag0_TC set, we bail out and wait for the TCP response containing the entire RRSet.
+ if (!InterfaceID && (response->h.flags.b[0] & kDNSFlag0_TC)) return;
+
+ if (LLQType == uDNS_LLQ_Ignore) return;
+
+ // 1. We ignore questions (if any) in mDNS response packets
+ // 2. If this is an LLQ response, we handle it much the same
+ // 3. If we get a uDNS UDP response with the TC (truncated) bit set, then we can't treat this
+ // answer as being the authoritative complete RRSet, and respond by deleting all other
+ // matching cache records that don't appear in this packet.
+ // Otherwise, this is a authoritative uDNS answer, so arrange for any stale records to be purged
+ if (ResponseMCast || LLQType == uDNS_LLQ_Events || (response->h.flags.b[0] & kDNSFlag0_TC))
+ ptr = LocateAnswers(response, end);
+ // Otherwise, for one-shot queries, any answers in our cache that are not also contained
+ // in this response packet are immediately deemed to be invalid.
+ else
+ {
+ mDNSBool failure, returnEarly;
+ rcode = (mDNSu8)(response->h.flags.b[1] & kDNSFlag1_RC_Mask);
+ failure = !(rcode == kDNSFlag1_RC_NoErr || rcode == kDNSFlag1_RC_NXDomain || rcode == kDNSFlag1_RC_NotAuth);
+ returnEarly = mDNSfalse;
+ // We could possibly combine this with the similar loop at the end of this function --
+ // instead of tagging cache records here and then rescuing them if we find them in the answer section,
+ // we could instead use the "m->PktNum" mechanism to tag each cache record with the packet number in
+ // which it was received (or refreshed), and then at the end if we find any cache records which
+ // answer questions in this packet's question section, but which aren't tagged with this packet's
+ // packet number, then we deduce they are old and delete them
+ for (i = 0; i < response->h.numQuestions && ptr && ptr < end; i++)
+ {
+ DNSQuestion q, *qptr = mDNSNULL;
+ ptr = getQuestion(response, ptr, end, InterfaceID, &q);
+ if (ptr && (qptr = ExpectingUnicastResponseForQuestion(m, dstport, response->h.id, &q, !dstaddr)))
+ {
+ if (!failure)
+ {
+ CacheRecord *rr;
+ // Remember the unicast question that we found, which we use to make caching
+ // decisions later on in this function
+ const mDNSu32 slot = HashSlot(&q.qname);
+ CacheGroup *cg = CacheGroupForName(m, slot, q.qnamehash, &q.qname);
+ if (!mDNSOpaque16IsZero(response->h.id))
+ {
+ unicastQuestion = qptr;
+ if (qptr->qDNSServer && DNSSECQuestion(qptr))
+ {
+ LogInfo("mDNSCoreReceiveResponse: Setting aware for %##s (%s) on %#a", qptr->qname.c,
+ DNSTypeName(qptr->qtype), &qptr->qDNSServer->addr);
+ qptr->qDNSServer->DNSSECAware = mDNStrue;
+ qptr->qDNSServer->req_DO = mDNStrue;
+ }
+ if (qptr->ValidatingResponse)
+ DNSSECQuestion = mDNStrue;
+ }
+ for (rr = cg ? cg->members : mDNSNULL; rr; rr=rr->next)
+ if (SameNameRecordAnswersQuestion(&rr->resrec, qptr))
+ {
+ debugf("uDNS marking %p %##s (%s) %p %s", q.InterfaceID, q.qname.c, DNSTypeName(q.qtype),
+ rr->resrec.InterfaceID, CRDisplayString(m, rr));
+ // Don't want to disturb rroriginalttl here, because code below might need it for the exponential backoff doubling algorithm
+ rr->TimeRcvd = m->timenow - TicksTTL(rr) - 1;
+ rr->UnansweredQueries = MaxUnansweredQueries;
+ rr->CRDNSSECQuestion = 0;
+ if (unicastQuestion && DNSSECQuestion(unicastQuestion))
+ {
+ LogInfo("mDNSCoreReceiveResponse: CRDNSSECQuestion set for record %s, question %##s (%s)", CRDisplayString(m, rr),
+ unicastQuestion->qname.c, DNSTypeName(unicastQuestion->qtype));
+ rr->CRDNSSECQuestion = 1;
+ }
+ }
+ }
+ else
+ {
+ if (qptr)
+ {
+ // If we recv any error from the DNSServer for a DNSSEC Query and if we know that the server
+ // is not DNSSEC aware, stop doing DNSSEC for that DNSServer. Note that by setting the
+ // req_DO to false here, the next retransmission for this question will turn off validation
+ // and hence retransmit without the EDNS0/DOK option.
+ if (DNSSECOptionalQuestion(qptr) && qptr->qDNSServer && !qptr->qDNSServer->DNSSECAware)
+ {
+ LogInfo("mDNSCoreReceiveResponse: Server %p responded with code %d to DNSSEC Query %##s (%s), clear DO flag",
+ qptr->qDNSServer, rcode, q.qname.c, DNSTypeName(q.qtype));
+ qptr->qDNSServer->req_DO = mDNSfalse;
+ }
+ // For Unicast DNS Queries, penalize the DNSServer
+ else
+ {
+ LogInfo("mDNSCoreReceiveResponse: Server %p responded with code %d to query %##s (%s)",
+ qptr->qDNSServer, rcode, q.qname.c, DNSTypeName(q.qtype));
+ PenalizeDNSServer(m, qptr, response->h.flags);
+ }
+ }
+ returnEarly = mDNStrue;
+ }
+ }
+ }
+ if (returnEarly)
+ {
+ LogInfo("Ignoring %2d Answer%s %2d Authorit%s %2d Additional%s",
+ response->h.numAnswers, response->h.numAnswers == 1 ? ", " : "s,",
+ response->h.numAuthorities, response->h.numAuthorities == 1 ? "y, " : "ies,",
+ response->h.numAdditionals, response->h.numAdditionals == 1 ? "" : "s");
+ // not goto exit because we won't have any CacheFlushRecords and we do not want to
+ // generate negative cache entries (we want to query the next server)
+ return;
+ }
+ if (unicastQuestion && DNSSECQuestion(unicastQuestion))
+ {
+ BumpDNSSECStats(m, kStatsActionSet, kStatsTypeMsgSize, (end - response->data));
+ }
+ }
+
+ // Parse the NSEC3 records from the Authority section before we process
+ // the Answer section so that we can cache them along with the proper
+ // cache records we create.
+ if (mDNSOpaque16IsZero(response->h.id))
+ mDNSParseNSEC3Records(m, response, end, InterfaceID, &McastNSEC3Records);
+
+ for (i = 0; i < totalrecords && ptr && ptr < end; i++)
+ {
+ // All responses sent via LL multicast are acceptable for caching
+ // All responses received over our outbound TCP connections are acceptable for caching
+ mDNSBool AcceptableResponse = ResponseMCast || !dstaddr || LLQType;
+ // (Note that just because we are willing to cache something, that doesn't necessarily make it a trustworthy answer
+ // to any specific question -- any code reading records from the cache needs to make that determination for itself.)
+
+ const mDNSu8 RecordType =
+ (i < firstauthority ) ? (mDNSu8)kDNSRecordTypePacketAns :
+ (i < firstadditional) ? (mDNSu8)kDNSRecordTypePacketAuth : (mDNSu8)kDNSRecordTypePacketAdd;
+ ptr = GetLargeResourceRecord(m, response, ptr, end, InterfaceID, RecordType, &m->rec);
+ if (!ptr) goto exit; // Break out of the loop and clean up our CacheFlushRecords list before exiting
+
+ if (m->rec.r.resrec.RecordType == kDNSRecordTypePacketNegative)
+ {
+ mDNSCoreResetRecord(m);
+ continue;
+ }
+
+ // We have already parsed the NSEC3 records and cached them approrpriately for
+ // multicast responses.
+ if (mDNSOpaque16IsZero(response->h.id) && m->rec.r.resrec.rrtype == kDNSType_NSEC3)
+ {
+ mDNSCoreResetRecord(m);
+ continue;
+ }
+ // Don't want to cache OPT or TSIG pseudo-RRs
+ if (m->rec.r.resrec.rrtype == kDNSType_TSIG)
+ {
+ mDNSCoreResetRecord(m);
+ continue;
+ }
+ if (m->rec.r.resrec.rrtype == kDNSType_OPT)
+ {
+ const rdataOPT *opt;
+ const rdataOPT *const e = (const rdataOPT *)&m->rec.r.resrec.rdata->u.data[m->rec.r.resrec.rdlength];
+ // Find owner sub-option(s). We verify that the MAC is non-zero, otherwise we could inadvertently
+ // delete all our own AuthRecords (which are identified by having zero MAC tags on them).
+ for (opt = &m->rec.r.resrec.rdata->u.opt[0]; opt < e; opt++)
+ if (opt->opt == kDNSOpt_Owner && opt->u.owner.vers == 0 && opt->u.owner.HMAC.l[0])
+ {
+ ClearProxyRecords(m, &opt->u.owner, m->DuplicateRecords);
+ ClearProxyRecords(m, &opt->u.owner, m->ResourceRecords);
+ }
+ mDNSCoreResetRecord(m);
+ continue;
+ }
+ // if a CNAME record points to itself, then don't add it to the cache
+ if ((m->rec.r.resrec.rrtype == kDNSType_CNAME) && SameDomainName(m->rec.r.resrec.name, &m->rec.r.resrec.rdata->u.name))
+ {
+ LogInfo("mDNSCoreReceiveResponse: CNAME loop domain name %##s", m->rec.r.resrec.name->c);
+ mDNSCoreResetRecord(m);
+ continue;
+ }
+
+ // When we receive uDNS LLQ responses, we assume a long cache lifetime --
+ // In the case of active LLQs, we'll get remove events when the records actually do go away
+ // In the case of polling LLQs, we assume the record remains valid until the next poll
+ if (!mDNSOpaque16IsZero(response->h.id))
+ m->rec.r.resrec.rroriginalttl = GetEffectiveTTL(LLQType, m->rec.r.resrec.rroriginalttl);
+
+ // If response was not sent via LL multicast,
+ // then see if it answers a recent query of ours, which would also make it acceptable for caching.
+ if (!ResponseMCast)
+ {
+ if (LLQType)
+ {
+ // For Long Lived queries that are both sent over UDP and Private TCP, LLQType is set.
+ // Even though it is AcceptableResponse, we need a matching DNSServer pointer for the
+ // queries to get ADD/RMV events. To lookup the question, we can't use
+ // ExpectingUnicastResponseForRecord as the port numbers don't match. uDNS_recvLLQRespose
+ // has already matched the question using the 64 bit Id in the packet and we use that here.
+
+ if (llqMatch != mDNSNULL) m->rec.r.resrec.rDNSServer = uDNSServer = llqMatch->qDNSServer;
+
+ // If this is a DNSSEC question that is also LongLived, don't accept records from the
+ // Additional/Authority section blindly. We need to go through IsAcceptableResponse below
+ // so that NSEC/NSEC3 record are cached in the nseclist if we accept them. This can happen
+ // for both negative responses and wildcard expanded positive responses as both of come
+ // back with NSEC/NSEC3s.
+ if (unicastQuestion && DNSSECQuestion(unicastQuestion))
+ AcceptableResponse = mDNSfalse;
+ }
+ else if (!AcceptableResponse || !dstaddr)
+ {
+ // For responses that come over TCP (Responses that can't fit within UDP) or TLS (Private queries
+ // that are not long lived e.g., AAAA lookup in a Private domain), it is indicated by !dstaddr.
+ // Even though it is AcceptableResponse, we still need a DNSServer pointer for the resource records that
+ // we create.
+
+ if (!mDNSOpaque16IsZero(response->h.id))
+ {
+ DNSQuestion *q = ExpectingUnicastResponseForRecord(m, srcaddr, ResponseSrcLocal, dstport, response->h.id, &m->rec.r, !dstaddr);
+
+ // Initialize the DNS server on the resource record which will now filter what questions we answer with
+ // this record.
+ //
+ // We could potentially lookup the DNS server based on the source address, but that may not work always
+ // and that's why ExpectingUnicastResponseForRecord does not try to verify whether the response came
+ // from the DNS server that queried. We follow the same logic here. If we can find a matching quetion based
+ // on the "id" and "source port", then this response answers the question and assume the response
+ // came from the same DNS server that we sent the query to.
+
+ if (q != mDNSNULL)
+ {
+ AcceptableResponse = mDNStrue;
+ if (!InterfaceID)
+ {
+ debugf("mDNSCoreReceiveResponse: InterfaceID %p %##s (%s)", q->InterfaceID, q->qname.c, DNSTypeName(q->qtype));
+ m->rec.r.resrec.rDNSServer = uDNSServer = q->qDNSServer;
+ }
+ else
+ LogInfo("mDNSCoreReceiveResponse: InterfaceID %p %##s (%s)", q->InterfaceID, q->qname.c, DNSTypeName(q->qtype));
+ }
+ else
+ {
+ // If we can't find a matching question, we need to see whether we have seen records earlier that matched
+ // the question. The code below does that. So, make this record unacceptable for now
+ if (!InterfaceID)
+ {
+ debugf("mDNSCoreReceiveResponse: Can't find question for record name %##s", m->rec.r.resrec.name->c);
+ AcceptableResponse = mDNSfalse;
+ }
+ }
+ }
+ else if (ExpectingMulticastResponseForRecord(m, &m->rec.r, srcaddr, recordAccepted, &McastNSEC3Records))
+ {
+ recordAccepted = mDNStrue;
+ AcceptableResponse = mDNStrue;
+ LogInfo("mDNSCoreReceiveResponse: Accepting record in response to QU question %s, InterfaceID %p", CRDisplayString(m, &m->rec.r),
+ InterfaceID);
+ }
+ else if (IsDeviceInfoRecord(m->rec.r.resrec.name))
+ {
+ recordAccepted = mDNStrue;
+ AcceptableResponse = mDNStrue;
+ LogInfo("mDNSCoreReceiveResponse: Accepting _device-info record %s, InterfaceID %p",
+ CRDisplayString(m, &m->rec.r), InterfaceID);
+ }
+ }
+ }
+ else if (llintf && llintf->IgnoreIPv4LL && m->rec.r.resrec.rrtype == kDNSType_A)
+ {
+ CacheRecord *const rr = &m->rec.r;
+ RDataBody2 *const rdb = (RDataBody2 *)rr->smallrdatastorage.data;
+
+ // If we are supposed to ignore link-local addresses on this interface, drop
+ // all "A" records that have link-local address in them.
+ if (mDNSv4AddressIsLinkLocal(&rdb->ipv4))
+ {
+ LogInfo("mDNSResponder: Dropping LinkLocal packet %s", CRDisplayString(m, &m->rec.r));
+ mDNSCoreResetRecord(m);
+ continue;
+ }
+ }
+
+ // 1. Check that this packet resource record does not conflict with any of ours
+ if (mDNSOpaque16IsZero(response->h.id) && m->rec.r.resrec.rrtype != kDNSType_NSEC)
+ {
+ if (m->CurrentRecord)
+ LogMsg("mDNSCoreReceiveResponse ERROR m->CurrentRecord already set %s", ARDisplayString(m, m->CurrentRecord));
+ m->CurrentRecord = m->ResourceRecords;
+ while (m->CurrentRecord)
+ {
+ AuthRecord *rr = m->CurrentRecord;
+ m->CurrentRecord = rr->next;
+ // We accept all multicast responses, and unicast responses resulting from queries we issued
+ // For other unicast responses, this code accepts them only for responses with an
+ // (apparently) local source address that pertain to a record of our own that's in probing state
+ if (!AcceptableResponse && !(ResponseSrcLocal && rr->resrec.RecordType == kDNSRecordTypeUnique)) continue;
+
+ if (PacketRRMatchesSignature(&m->rec.r, rr)) // If interface, name, type (if shared record) and class match...
+ {
+ // ... check to see if type and rdata are identical
+ if (IdenticalSameNameRecord(&m->rec.r.resrec, &rr->resrec))
+ {
+ // If the RR in the packet is identical to ours, just check they're not trying to lower the TTL on us
+ if (m->rec.r.resrec.rroriginalttl >= rr->resrec.rroriginalttl/2 || m->SleepState)
+ {
+ // If we were planning to send on this -- and only this -- interface, then we don't need to any more
+ if (rr->ImmedAnswer == InterfaceID) { rr->ImmedAnswer = mDNSNULL; rr->ImmedUnicast = mDNSfalse; }
+ }
+ else
+ {
+ if (rr->ImmedAnswer == mDNSNULL) { rr->ImmedAnswer = InterfaceID; m->NextScheduledResponse = m->timenow; }
+ else if (rr->ImmedAnswer != InterfaceID) { rr->ImmedAnswer = mDNSInterfaceMark; m->NextScheduledResponse = m->timenow; }
+ }
+ }
+ // else, the packet RR has different type or different rdata -- check to see if this is a conflict
+ else if (m->rec.r.resrec.rroriginalttl > 0 && PacketRRConflict(m, rr, &m->rec.r))
+ {
+ LogInfo("mDNSCoreReceiveResponse: Pkt Record: %08lX %s", m->rec.r.resrec.rdatahash, CRDisplayString(m, &m->rec.r));
+ LogInfo("mDNSCoreReceiveResponse: Our Record: %08lX %s", rr->resrec.rdatahash, ARDisplayString(m, rr));
+
+ // If this record is marked DependentOn another record for conflict detection purposes,
+ // then *that* record has to be bumped back to probing state to resolve the conflict
+ if (rr->DependentOn)
+ {
+ while (rr->DependentOn) rr = rr->DependentOn;
+ LogInfo("mDNSCoreReceiveResponse: Dep Record: %08lX %s", rr->resrec.rdatahash, ARDisplayString(m, rr));
+ }
+
+ // If we've just whacked this record's ProbeCount, don't need to do it again
+ if (rr->ProbeCount > DefaultProbeCountForTypeUnique)
+ LogInfo("mDNSCoreReceiveResponse: Already reset to Probing: %s", ARDisplayString(m, rr));
+ else if (rr->ProbeCount == DefaultProbeCountForTypeUnique)
+ LogMsg("mDNSCoreReceiveResponse: Ignoring response received before we even began probing: %s", ARDisplayString(m, rr));
+ else
+ {
+ LogMsg("mDNSCoreReceiveResponse: Received from %#a:%d %s", srcaddr, mDNSVal16(srcport), CRDisplayString(m, &m->rec.r));
+ // If we'd previously verified this record, put it back to probing state and try again
+ if (rr->resrec.RecordType == kDNSRecordTypeVerified)
+ {
+ LogMsg("mDNSCoreReceiveResponse: Resetting to Probing: %s", ARDisplayString(m, rr));
+ rr->resrec.RecordType = kDNSRecordTypeUnique;
+ // We set ProbeCount to one more than the usual value so we know we've already touched this record.
+ // This is because our single probe for "example-name.local" could yield a response with (say) two A records and
+ // three AAAA records in it, and we don't want to call RecordProbeFailure() five times and count that as five conflicts.
+ // This special value is recognised and reset to DefaultProbeCountForTypeUnique in SendQueries().
+ rr->ProbeCount = DefaultProbeCountForTypeUnique + 1;
+ rr->AnnounceCount = InitialAnnounceCount;
+ InitializeLastAPTime(m, rr);
+ RecordProbeFailure(m, rr); // Repeated late conflicts also cause us to back off to the slower probing rate
+ }
+ // If we're probing for this record, we just failed
+ else if (rr->resrec.RecordType == kDNSRecordTypeUnique)
+ {
+ // Before we call deregister, check if this is a packet we registered with the sleep proxy.
+ if (!mDNSCoreRegisteredProxyRecord(m, rr))
+ {
+ LogMsg("mDNSCoreReceiveResponse: ProbeCount %d; will deregister %s", rr->ProbeCount, ARDisplayString(m, rr));
+
+ m->mDNSStats.NameConflicts++;
+ mDNS_Deregister_internal(m, rr, mDNS_Dereg_conflict);
+ }
+ }
+ // We assumed this record must be unique, but we were wrong. (e.g. There are two mDNSResponders on the
+ // same machine giving different answers for the reverse mapping record, or there are two machines on the
+ // network using the same IP address.) This is simply a misconfiguration, and there's nothing we can do
+ // to fix it -- e.g. it's not our job to be trying to change the machine's IP address. We just discard our
+ // record to avoid continued conflicts (as we do for a conflict on our Unique records) and get on with life.
+ else if (rr->resrec.RecordType == kDNSRecordTypeKnownUnique)
+ {
+ LogMsg("mDNSCoreReceiveResponse: Unexpected conflict discarding %s", ARDisplayString(m, rr));
+ m->mDNSStats.KnownUniqueNameConflicts++;
+ mDNS_Deregister_internal(m, rr, mDNS_Dereg_conflict);
+ }
+ else
+ LogMsg("mDNSCoreReceiveResponse: Unexpected record type %X %s", rr->resrec.RecordType, ARDisplayString(m, rr));
+ }
+ }
+ // Else, matching signature, different type or rdata, but not a considered a conflict.
+ // If the packet record has the cache-flush bit set, then we check to see if we
+ // have any record(s) of the same type that we should re-assert to rescue them
+ // (see note about "multi-homing and bridged networks" at the end of this function).
+ else if (m->rec.r.resrec.rrtype == rr->resrec.rrtype)
+ if ((m->rec.r.resrec.RecordType & kDNSRecordTypePacketUniqueMask) && m->timenow - rr->LastMCTime > mDNSPlatformOneSecond/2)
+ { rr->ImmedAnswer = mDNSInterfaceMark; m->NextScheduledResponse = m->timenow; }
+ }
+ }
+ }
+
+ nseclist = mDNSfalse;
+ if (!AcceptableResponse)
+ {
+ AcceptableResponse = IsResponseAcceptable(m, CacheFlushRecords, unicastQuestion, &nseclist);
+ if (AcceptableResponse) m->rec.r.resrec.rDNSServer = uDNSServer;
+ }
+
+ // 2. See if we want to add this packet resource record to our cache
+ // We only try to cache answers if we have a cache to put them in
+ // Also, we ignore any apparent attempts at cache poisoning unicast to us that do not answer any outstanding active query
+ if (!AcceptableResponse) LogInfo("mDNSCoreReceiveResponse ignoring %s", CRDisplayString(m, &m->rec.r));
+ if (m->rrcache_size && AcceptableResponse)
+ {
+ const mDNSu32 slot = HashSlot(m->rec.r.resrec.name);
+ CacheGroup *cg = CacheGroupForRecord(m, slot, &m->rec.r.resrec);
+ CacheRecord *rr = mDNSNULL;
+
+ if (McastNSEC3Records)
+ InitializeAnonInfoForCR(m, &McastNSEC3Records, &m->rec.r);
+
+ // 2a. Check if this packet resource record is already in our cache.
+ //
+ // If this record should go in the nseclist, don't look in the cache for updating it.
+ // They are supposed to be cached under the "nsec" field of the cache record for
+ // validation. Just create the cache record.
+ if (!nseclist)
+ {
+ rr = mDNSCoreReceiveCacheCheck(m, response, LLQType, slot, cg, unicastQuestion, &cfp, &NSECCachePtr, InterfaceID);
+ }
+
+ // If mDNSOppCaching is set (which affects only multicast), enable opportunistic caching in which case we cache
+ // everything that was received over multicast. Otherwise, we are selective about the caching.
+ //
+ // Cache everything that is from ourselves (that's how we answer any questions looking for them). Otherwise call
+ // ExpectingMulticastResponseForRecord which decides whether to cache this record or not.
+ //
+ if (!m->mDNSOppCaching && !rr && !myself && mDNSOpaque16IsZero(response->h.id))
+ {
+ if (!ExpectingMulticastResponseForRecord(m, &m->rec.r, srcaddr, recordAccepted, &McastNSEC3Records))
+ {
+ //LogMsg("mDNSCoreReceiveResponse: discarding %s", CRDisplayString(m, &m->rec.r));
+ mDNSCoreResetRecord(m);
+ continue;
+ }
+ else
+ {
+ recordAccepted = mDNStrue;
+ }
+ }
+
+
+ // If packet resource record not in our cache, add it now
+ // (unless it is just a deletion of a record we never had, in which case we don't care)
+ if (!rr && m->rec.r.resrec.rroriginalttl > 0)
+ {
+ const mDNSBool AddToCFList = (m->rec.r.resrec.RecordType & kDNSRecordTypePacketUniqueMask) && (LLQType != uDNS_LLQ_Events);
+ mDNSs32 delay;
+
+ if (AddToCFList)
+ delay = NonZeroTime(m->timenow + mDNSPlatformOneSecond);
+ else
+ delay = CheckForSoonToExpireRecords(m, m->rec.r.resrec.name, m->rec.r.resrec.namehash, slot, mDNSNULL);
+
+ // If unique, assume we may have to delay delivery of this 'add' event.
+ // Below, where we walk the CacheFlushRecords list, we either call CacheRecordDeferredAdd()
+ // to immediately to generate answer callbacks, or we call ScheduleNextCacheCheckTime()
+ // to schedule an mDNS_Execute task at the appropriate time.
+ rr = CreateNewCacheEntry(m, slot, cg, delay, !nseclist, srcaddr);
+ if (rr)
+ {
+ rr->responseFlags = response->h.flags;
+ // If we are not creating signatures, then we need to inform DNSSEC so that
+ // it does not wait forever. Don't do this if we got NSEC records
+ // as it indicates that this name does not exist.
+ if (rr->resrec.rrtype == kDNSType_RRSIG && !nseclist)
+ {
+ rrsigsCreated = mDNStrue;
+ }
+ // Remember whether we created a cache record in response to a DNSSEC question.
+ // This helps DNSSEC code not to reissue the question to fetch the DNSSEC records.
+ rr->CRDNSSECQuestion = 0;
+ if (unicastQuestion && DNSSECQuestion(unicastQuestion))
+ {
+ LogInfo("mDNSCoreReceiveResponse: CRDNSSECQuestion set for new record %s, question %##s (%s)", CRDisplayString(m, rr),
+ unicastQuestion->qname.c, DNSTypeName(unicastQuestion->qtype));
+ rr->CRDNSSECQuestion = 1;
+ }
+ // NSEC/NSEC3 records and its signatures are cached with the negative cache entry
+ // which we should be creating below. It is also needed in the wildcard
+ // expanded answer case and in that case it is cached along with the answer.
+ if (nseclist)
+ {
+ rr->TimeRcvd = m->timenow;
+ *nsecp = rr;
+ nsecp = &rr->next;
+ }
+ else if (AddToCFList)
+ {
+ *cfp = rr;
+ cfp = &rr->NextInCFList;
+ *cfp = (CacheRecord*)1;
+ }
+ else if (rr->DelayDelivery)
+ {
+ ScheduleNextCacheCheckTime(m, slot, rr->DelayDelivery);
+ }
+ }
+ }
+ else
+ {
+ if (rr && rr->resrec.AnonInfo && m->rec.r.resrec.AnonInfo)
+ {
+ CopyAnonInfoForCR(m, rr, &m->rec.r);
+ }
+ }
+ }
+ mDNSCoreResetRecord(m);
+ }
exit:
- m->rec.r.resrec.RecordType = 0; // Clear RecordType to show we're not still using it
-
- // If we've just received one or more records with their cache flush bits set,
- // then scan that cache slot to see if there are any old stale records we need to flush
- while (CacheFlushRecords != (CacheRecord*)1)
- {
- CacheRecord *r1 = CacheFlushRecords, *r2;
- const mDNSu32 slot = HashSlot(r1->resrec.name);
- const CacheGroup *cg = CacheGroupForRecord(m, slot, &r1->resrec);
- CacheFlushRecords = CacheFlushRecords->NextInCFList;
- r1->NextInCFList = mDNSNULL;
-
- // Look for records in the cache with the same signature as this new one with the cache flush
- // bit set, and either (a) if they're fresh, just make sure the whole RRSet has the same TTL
- // (as required by DNS semantics) or (b) if they're old, mark them for deletion in one second.
- // We make these TTL adjustments *only* for records that still have *more* than one second
- // remaining to live. Otherwise, a record that we tagged for deletion half a second ago
- // (and now has half a second remaining) could inadvertently get its life extended, by either
- // (a) if we got an explicit goodbye packet half a second ago, the record would be considered
- // "fresh" and would be incorrectly resurrected back to the same TTL as the rest of the RRSet,
- // or (b) otherwise, the record would not be fully resurrected, but would be reset to expire
- // in one second, thereby inadvertently delaying its actual expiration, instead of hastening it.
- // If this were to happen repeatedly, the record's expiration could be deferred indefinitely.
- // To avoid this, we need to ensure that the cache flushing operation will only act to
- // *decrease* a record's remaining lifetime, never *increase* it.
- for (r2 = cg ? cg->members : mDNSNULL; r2; r2=r2->next)
- // For Unicast (null InterfaceID) the DNSservers should also match
- if ((r1->resrec.InterfaceID == r2->resrec.InterfaceID) &&
- (r1->resrec.InterfaceID || (r1->resrec.rDNSServer == r2->resrec.rDNSServer)) &&
- r1->resrec.rrtype == r2->resrec.rrtype &&
- r1->resrec.rrclass == r2->resrec.rrclass)
- {
- // If record is recent, just ensure the whole RRSet has the same TTL (as required by DNS semantics)
- // else, if record is old, mark it to be flushed
- if (m->timenow - r2->TimeRcvd < mDNSPlatformOneSecond && RRExpireTime(r2) - m->timenow > mDNSPlatformOneSecond)
- {
- // If we find mismatched TTLs in an RRSet, correct them.
- // We only do this for records with a TTL of 2 or higher. It's possible to have a
- // goodbye announcement with the cache flush bit set (or a case-change on record rdata,
- // which we treat as a goodbye followed by an addition) and in that case it would be
- // inappropriate to synchronize all the other records to a TTL of 0 (or 1).
- // We suppress the message for the specific case of correcting from 240 to 60 for type TXT,
- // because certain early Bonjour devices are known to have this specific mismatch, and
- // there's no point filling syslog with messages about something we already know about.
- // We also don't log this for uDNS responses, since a caching name server is obliged
- // to give us an aged TTL to correct for how long it has held the record,
- // so our received TTLs are expected to vary in that case
- if (r2->resrec.rroriginalttl != r1->resrec.rroriginalttl && r1->resrec.rroriginalttl > 1)
- {
- if (!(r2->resrec.rroriginalttl == 240 && r1->resrec.rroriginalttl == 60 && r2->resrec.rrtype == kDNSType_TXT) &&
- mDNSOpaque16IsZero(response->h.id))
- LogInfo("Correcting TTL from %4d to %4d for %s",
- r2->resrec.rroriginalttl, r1->resrec.rroriginalttl, CRDisplayString(m, r2));
- r2->resrec.rroriginalttl = r1->resrec.rroriginalttl;
- }
- r2->TimeRcvd = m->timenow;
- }
- else // else, if record is old, mark it to be flushed
- {
- verbosedebugf("Cache flush new %p age %d expire in %d %s", r1, m->timenow - r1->TimeRcvd, RRExpireTime(r1) - m->timenow, CRDisplayString(m, r1));
- verbosedebugf("Cache flush old %p age %d expire in %d %s", r2, m->timenow - r2->TimeRcvd, RRExpireTime(r2) - m->timenow, CRDisplayString(m, r2));
- // We set stale records to expire in one second.
- // This gives the owner a chance to rescue it if necessary.
- // This is important in the case of multi-homing and bridged networks:
- // Suppose host X is on Ethernet. X then connects to an AirPort base station, which happens to be
- // bridged onto the same Ethernet. When X announces its AirPort IP address with the cache-flush bit
- // set, the AirPort packet will be bridged onto the Ethernet, and all other hosts on the Ethernet
- // will promptly delete their cached copies of the (still valid) Ethernet IP address record.
- // By delaying the deletion by one second, we give X a change to notice that this bridging has
- // happened, and re-announce its Ethernet IP address to rescue it from deletion from all our caches.
-
- // We set UnansweredQueries to MaxUnansweredQueries to avoid expensive and unnecessary
- // final expiration queries for this record.
-
- // If a record is deleted twice, first with an explicit DE record, then a second time by virtue of the cache
- // flush bit on the new record replacing it, then we allow the record to be deleted immediately, without the usual
- // one-second grace period. This improves responsiveness for mDNS_Update(), as used for things like iChat status updates.
- // <rdar://problem/5636422> Updating TXT records is too slow
- // We check for "rroriginalttl == 1" because we want to include records tagged by the "packet TTL is zero" check above,
- // which sets rroriginalttl to 1, but not records tagged by the rdata case-change check, which sets rroriginalttl to 0.
- if (r2->TimeRcvd == m->timenow && r2->resrec.rroriginalttl == 1 && r2->UnansweredQueries == MaxUnansweredQueries)
- {
- LogInfo("Cache flush for DE record %s", CRDisplayString(m, r2));
- r2->resrec.rroriginalttl = 0;
- }
- else if (RRExpireTime(r2) - m->timenow > mDNSPlatformOneSecond)
- {
- // We only set a record to expire in one second if it currently has *more* than a second to live
- // If it's already due to expire in a second or less, we just leave it alone
- r2->resrec.rroriginalttl = 1;
- r2->UnansweredQueries = MaxUnansweredQueries;
- r2->TimeRcvd = m->timenow - 1;
- // We use (m->timenow - 1) instead of m->timenow, because we use that to identify records
- // that we marked for deletion via an explicit DE record
- }
- }
- SetNextCacheCheckTimeForRecord(m, r2);
- }
-
- if (r1->DelayDelivery) // If we were planning to delay delivery of this record, see if we still need to
- {
- r1->DelayDelivery = CheckForSoonToExpireRecords(m, r1->resrec.name, r1->resrec.namehash, slot);
- // If no longer delaying, deliver answer now, else schedule delivery for the appropriate time
- if (!r1->DelayDelivery) CacheRecordDeferredAdd(m, r1);
- else ScheduleNextCacheCheckTime(m, slot, r1->DelayDelivery);
- }
- }
-
- // See if we need to generate negative cache entries for unanswered unicast questions
- ptr = response->data;
- for (i = 0; i < response->h.numQuestions && ptr && ptr < end; i++)
- {
- DNSQuestion q;
- DNSQuestion *qptr = mDNSNULL;
- ptr = getQuestion(response, ptr, end, InterfaceID, &q);
- if (ptr && (qptr = ExpectingUnicastResponseForQuestion(m, dstport, response->h.id, &q, !dstaddr)))
- {
- CacheRecord *rr, *neg = mDNSNULL;
- mDNSu32 slot = HashSlot(&q.qname);
- CacheGroup *cg = CacheGroupForName(m, slot, q.qnamehash, &q.qname);
- for (rr = cg ? cg->members : mDNSNULL; rr; rr=rr->next)
- if (SameNameRecordAnswersQuestion(&rr->resrec, qptr))
- {
- // 1. If we got a fresh answer to this query, then don't need to generate a negative entry
- if (RRExpireTime(rr) - m->timenow > 0) break;
- // 2. If we already had a negative entry, keep track of it so we can resurrect it instead of creating a new one
- if (rr->resrec.RecordType == kDNSRecordTypePacketNegative) neg = rr;
- }
- // When we're doing parallel unicast and multicast queries for dot-local names (for supporting Microsoft
- // Active Directory sites) we don't want to waste memory making negative cache entries for all the unicast answers.
- // Otherwise we just fill up our cache with negative entries for just about every single multicast name we ever look up
- // (since the Microsoft Active Directory server is going to assert that pretty much every single multicast name doesn't exist).
- // This is not only a waste of memory, but there's also the problem of those negative entries confusing us later -- e.g. we
- // suppress sending our mDNS query packet because we think we already have a valid (negative) answer to that query in our cache.
- // The one exception is that we *DO* want to make a negative cache entry for "local. SOA", for the (common) case where we're
- // *not* on a Microsoft Active Directory network, and there is no authoritative server for "local". Note that this is not
- // in conflict with the mDNS spec, because that spec says, "Multicast DNS Zones have no SOA record," so it's okay to cache
- // negative answers for "local. SOA" from a uDNS server, because the mDNS spec already says that such records do not exist :-)
- //
- // By suppressing negative responses, it might take longer to timeout a .local question as it might be expecting a
- // response e.g., we deliver a positive "A" response and suppress negative "AAAA" response and the upper layer may
- // be waiting longer to get the AAAA response before returning the "A" response to the application. To handle this
- // case without creating the negative cache entries, we generate a negative response and let the layer above us
- // do the appropriate thing. This negative response is also needed for appending new search domains.
- if (!InterfaceID && q.qtype != kDNSType_SOA && IsLocalDomain(&q.qname))
- {
- if (!rr)
- {
- LogInfo("mDNSCoreReceiveResponse: Generate negative response for %##s (%s)", q.qname.c, DNSTypeName(q.qtype));
- m->CurrentQuestion = qptr;
- GenerateNegativeResponse(m);
- m->CurrentQuestion = mDNSNULL;
- }
- else LogInfo("mDNSCoreReceiveResponse: Skipping check to see if we need to generate a negative cache entry for %##s (%s)", q.qname.c, DNSTypeName(q.qtype));
- }
- else
- {
- if (!rr)
- {
- // We start off assuming a negative caching TTL of 60 seconds
- // but then look to see if we can find an SOA authority record to tell us a better value we should be using
- mDNSu32 negttl = 60;
- int repeat = 0;
- const domainname *name = &q.qname;
- mDNSu32 hash = q.qnamehash;
-
- // Special case for our special Microsoft Active Directory "local SOA" check.
- // Some cheap home gateways don't include an SOA record in the authority section when
- // they send negative responses, so we don't know how long to cache the negative result.
- // Because we don't want to keep hitting the root name servers with our query to find
- // if we're on a network using Microsoft Active Directory using "local" as a private
- // internal top-level domain, we make sure to cache the negative result for at least one day.
- if (q.qtype == kDNSType_SOA && SameDomainName(&q.qname, &localdomain)) negttl = 60 * 60 * 24;
-
- // If we're going to make (or update) a negative entry, then look for the appropriate TTL from the SOA record
- if (response->h.numAuthorities && (ptr = LocateAuthorities(response, end)) != mDNSNULL)
- {
- ptr = GetLargeResourceRecord(m, response, ptr, end, InterfaceID, kDNSRecordTypePacketAuth, &m->rec);
- if (ptr && m->rec.r.resrec.RecordType != kDNSRecordTypePacketNegative && m->rec.r.resrec.rrtype == kDNSType_SOA)
- {
- const rdataSOA *const soa = (const rdataSOA *)m->rec.r.resrec.rdata->u.data;
- mDNSu32 ttl_s = soa->min;
- // We use the lesser of the SOA.MIN field and the SOA record's TTL, *except*
- // for the SOA record for ".", where the record is reported as non-cacheable
- // (TTL zero) for some reason, so in this case we just take the SOA record's TTL as-is
- if (ttl_s > m->rec.r.resrec.rroriginalttl && m->rec.r.resrec.name->c[0])
- ttl_s = m->rec.r.resrec.rroriginalttl;
- if (negttl < ttl_s) negttl = ttl_s;
-
- // Special check for SOA queries: If we queried for a.b.c.d.com, and got no answer,
- // with an Authority Section SOA record for d.com, then this is a hint that the authority
- // is d.com, and consequently SOA records b.c.d.com and c.d.com don't exist either.
- // To do this we set the repeat count so the while loop below will make a series of negative cache entries for us
- if (q.qtype == kDNSType_SOA)
- {
- int qcount = CountLabels(&q.qname);
- int scount = CountLabels(m->rec.r.resrec.name);
- if (qcount - 1 > scount)
- if (SameDomainName(SkipLeadingLabels(&q.qname, qcount - scount), m->rec.r.resrec.name))
- repeat = qcount - 1 - scount;
- }
- }
- m->rec.r.resrec.RecordType = 0; // Clear RecordType to show we're not still using it
- }
-
- // If we already had a negative entry in the cache, then we double our existing negative TTL. This is to avoid
- // the case where the record doesn't exist (e.g. particularly for things like our lb._dns-sd._udp.<domain> query),
- // and the server returns no SOA record (or an SOA record with a small MIN TTL) so we assume a TTL
- // of 60 seconds, and we end up polling the server every minute for a record that doesn't exist.
- // With this fix in place, when this happens, we double the effective TTL each time (up to one hour),
- // so that we back off our polling rate and don't keep hitting the server continually.
- if (neg)
- {
- if (negttl < neg->resrec.rroriginalttl * 2)
- negttl = neg->resrec.rroriginalttl * 2;
- if (negttl > 3600)
- negttl = 3600;
- }
-
- negttl = GetEffectiveTTL(LLQType, negttl); // Add 25% grace period if necessary
-
- // If we already had a negative cache entry just update it, else make one or more new negative cache entries
- if (neg)
- {
- debugf("Renewing negative TTL from %d to %d %s", neg->resrec.rroriginalttl, negttl, CRDisplayString(m, neg));
- RefreshCacheRecord(m, neg, negttl);
- }
- else while (1)
- {
- debugf("mDNSCoreReceiveResponse making negative cache entry TTL %d for %##s (%s)", negttl, name->c, DNSTypeName(q.qtype));
- MakeNegativeCacheRecord(m, &m->rec.r, name, hash, q.qtype, q.qclass, negttl, mDNSInterface_Any, qptr->qDNSServer);
- CreateNewCacheEntry(m, slot, cg, 0); // We never need any delivery delay for these generated negative cache records
- m->rec.r.resrec.RecordType = 0; // Clear RecordType to show we're not still using it
- if (!repeat) break;
- repeat--;
- name = (const domainname *)(name->c + 1 + name->c[0]);
- hash = DomainNameHashValue(name);
- slot = HashSlot(name);
- cg = CacheGroupForName(m, slot, hash, name);
- }
- }
- }
- }
- }
- }
+ mDNSCoreResetRecord(m);
+
+ // If we've just received one or more records with their cache flush bits set,
+ // then scan that cache slot to see if there are any old stale records we need to flush
+ while (CacheFlushRecords != (CacheRecord*)1)
+ {
+ CacheRecord *r1 = CacheFlushRecords, *r2;
+ const mDNSu32 slot = HashSlot(r1->resrec.name);
+ const CacheGroup *cg = CacheGroupForRecord(m, slot, &r1->resrec);
+ CacheFlushRecords = CacheFlushRecords->NextInCFList;
+ r1->NextInCFList = mDNSNULL;
+
+ // Look for records in the cache with the same signature as this new one with the cache flush
+ // bit set, and either (a) if they're fresh, just make sure the whole RRSet has the same TTL
+ // (as required by DNS semantics) or (b) if they're old, mark them for deletion in one second.
+ // We make these TTL adjustments *only* for records that still have *more* than one second
+ // remaining to live. Otherwise, a record that we tagged for deletion half a second ago
+ // (and now has half a second remaining) could inadvertently get its life extended, by either
+ // (a) if we got an explicit goodbye packet half a second ago, the record would be considered
+ // "fresh" and would be incorrectly resurrected back to the same TTL as the rest of the RRSet,
+ // or (b) otherwise, the record would not be fully resurrected, but would be reset to expire
+ // in one second, thereby inadvertently delaying its actual expiration, instead of hastening it.
+ // If this were to happen repeatedly, the record's expiration could be deferred indefinitely.
+ // To avoid this, we need to ensure that the cache flushing operation will only act to
+ // *decrease* a record's remaining lifetime, never *increase* it.
+ for (r2 = cg ? cg->members : mDNSNULL; r2; r2=r2->next)
+ {
+ mDNSu16 id1;
+ mDNSu16 id2;
+ if (!r1->resrec.InterfaceID)
+ {
+ id1 = (r1->resrec.rDNSServer ? r1->resrec.rDNSServer->resGroupID : 0);
+ id2 = (r2->resrec.rDNSServer ? r2->resrec.rDNSServer->resGroupID : 0);
+ }
+ else
+ {
+ id1 = id2 = 0;
+ }
+ // When we receive new RRSIGs e.g., for DNSKEY record, we should not flush the old
+ // RRSIGS e.g., for TXT record. To do so, we need to look at the typeCovered field of
+ // the new RRSIG that we received. Process only if the typeCovered matches.
+ if ((r1->resrec.rrtype == r2->resrec.rrtype) && (r1->resrec.rrtype == kDNSType_RRSIG))
+ {
+ rdataRRSig *rrsig1 = (rdataRRSig *)(((RDataBody2 *)(r1->resrec.rdata->u.data))->data);
+ rdataRRSig *rrsig2 = (rdataRRSig *)(((RDataBody2 *)(r2->resrec.rdata->u.data))->data);
+ if (swap16(rrsig1->typeCovered) != swap16(rrsig2->typeCovered))
+ {
+ debugf("mDNSCoreReceiveResponse: Received RRSIG typeCovered %s, found %s, not processing",
+ DNSTypeName(swap16(rrsig1->typeCovered)), DNSTypeName(swap16(rrsig2->typeCovered)));
+ continue;
+ }
+ }
+
+ // For Unicast (null InterfaceID) the resolver IDs should also match
+ if ((r1->resrec.InterfaceID == r2->resrec.InterfaceID) &&
+ (r1->resrec.InterfaceID || (id1 == id2)) &&
+ r1->resrec.rrtype == r2->resrec.rrtype &&
+ r1->resrec.rrclass == r2->resrec.rrclass)
+ {
+ // If record is recent, just ensure the whole RRSet has the same TTL (as required by DNS semantics)
+ // else, if record is old, mark it to be flushed
+ if (m->timenow - r2->TimeRcvd < mDNSPlatformOneSecond && RRExpireTime(r2) - m->timenow > mDNSPlatformOneSecond)
+ {
+ // If we find mismatched TTLs in an RRSet, correct them.
+ // We only do this for records with a TTL of 2 or higher. It's possible to have a
+ // goodbye announcement with the cache flush bit set (or a case-change on record rdata,
+ // which we treat as a goodbye followed by an addition) and in that case it would be
+ // inappropriate to synchronize all the other records to a TTL of 0 (or 1).
+ // We suppress the message for the specific case of correcting from 240 to 60 for type TXT,
+ // because certain early Bonjour devices are known to have this specific mismatch, and
+ // there's no point filling syslog with messages about something we already know about.
+ // We also don't log this for uDNS responses, since a caching name server is obliged
+ // to give us an aged TTL to correct for how long it has held the record,
+ // so our received TTLs are expected to vary in that case
+ if (r2->resrec.rroriginalttl != r1->resrec.rroriginalttl && r1->resrec.rroriginalttl > 1)
+ {
+ if (!(r2->resrec.rroriginalttl == 240 && r1->resrec.rroriginalttl == 60 && r2->resrec.rrtype == kDNSType_TXT) &&
+ mDNSOpaque16IsZero(response->h.id))
+ LogInfo("Correcting TTL from %4d to %4d for %s",
+ r2->resrec.rroriginalttl, r1->resrec.rroriginalttl, CRDisplayString(m, r2));
+ r2->resrec.rroriginalttl = r1->resrec.rroriginalttl;
+ }
+ r2->TimeRcvd = m->timenow;
+ }
+ else // else, if record is old, mark it to be flushed
+ {
+ verbosedebugf("Cache flush new %p age %d expire in %d %s", r1, m->timenow - r1->TimeRcvd, RRExpireTime(r1) - m->timenow, CRDisplayString(m, r1));
+ verbosedebugf("Cache flush old %p age %d expire in %d %s", r2, m->timenow - r2->TimeRcvd, RRExpireTime(r2) - m->timenow, CRDisplayString(m, r2));
+ // We set stale records to expire in one second.
+ // This gives the owner a chance to rescue it if necessary.
+ // This is important in the case of multi-homing and bridged networks:
+ // Suppose host X is on Ethernet. X then connects to an AirPort base station, which happens to be
+ // bridged onto the same Ethernet. When X announces its AirPort IP address with the cache-flush bit
+ // set, the AirPort packet will be bridged onto the Ethernet, and all other hosts on the Ethernet
+ // will promptly delete their cached copies of the (still valid) Ethernet IP address record.
+ // By delaying the deletion by one second, we give X a change to notice that this bridging has
+ // happened, and re-announce its Ethernet IP address to rescue it from deletion from all our caches.
+
+ // We set UnansweredQueries to MaxUnansweredQueries to avoid expensive and unnecessary
+ // final expiration queries for this record.
+
+ // If a record is deleted twice, first with an explicit DE record, then a second time by virtue of the cache
+ // flush bit on the new record replacing it, then we allow the record to be deleted immediately, without the usual
+ // one-second grace period. This improves responsiveness for mDNS_Update(), as used for things like iChat status updates.
+ // <rdar://problem/5636422> Updating TXT records is too slow
+ // We check for "rroriginalttl == 1" because we want to include records tagged by the "packet TTL is zero" check above,
+ // which sets rroriginalttl to 1, but not records tagged by the rdata case-change check, which sets rroriginalttl to 0.
+ if (r2->TimeRcvd == m->timenow && r2->resrec.rroriginalttl == 1 && r2->UnansweredQueries == MaxUnansweredQueries)
+ {
+ LogInfo("Cache flush for DE record %s", CRDisplayString(m, r2));
+ r2->resrec.rroriginalttl = 0;
+ }
+ else if (RRExpireTime(r2) - m->timenow > mDNSPlatformOneSecond)
+ {
+ // We only set a record to expire in one second if it currently has *more* than a second to live
+ // If it's already due to expire in a second or less, we just leave it alone
+ r2->resrec.rroriginalttl = 1;
+ r2->UnansweredQueries = MaxUnansweredQueries;
+ r2->TimeRcvd = m->timenow - 1;
+ // We use (m->timenow - 1) instead of m->timenow, because we use that to identify records
+ // that we marked for deletion via an explicit DE record
+ }
+ }
+ SetNextCacheCheckTimeForRecord(m, r2);
+ }
+ }
+
+ if (r1->DelayDelivery) // If we were planning to delay delivery of this record, see if we still need to
+ {
+ // If we had a unicast question for this response with at least one positive answer and we
+ // have NSECRecords, it is most likely a wildcard expanded answer. Cache the NSEC and its
+ // signatures along with the cache record which will be used for validation later. If
+ // we rescued a few records earlier in this function, then NSECCachePtr would be set. In that
+ // use that instead.
+ if (response->h.numAnswers && unicastQuestion && NSECRecords)
+ {
+ if (!NSECCachePtr)
+ {
+ LogInfo("mDNSCoreReceiveResponse: Updating NSECCachePtr to %s", CRDisplayString(m, r1));
+ NSECCachePtr = r1;
+ }
+ // Note: We need to do this before we call CacheRecordDeferredAdd as this
+ // might start the verification process which needs these NSEC records
+ if (!AddNSECSForCacheRecord(m, NSECRecords, NSECCachePtr, rcode))
+ {
+ LogInfo("mDNSCoreReceiveResponse: AddNSECSForCacheRecord failed to add NSEC for %s", CRDisplayString(m, NSECCachePtr));
+ FreeNSECRecords(m, NSECRecords);
+ }
+ NSECRecords = mDNSNULL;
+ NSECCachePtr = mDNSNULL;
+ }
+ r1->DelayDelivery = CheckForSoonToExpireRecords(m, r1->resrec.name, r1->resrec.namehash, slot, mDNSNULL);
+ // If no longer delaying, deliver answer now, else schedule delivery for the appropriate time
+ if (!r1->DelayDelivery) CacheRecordDeferredAdd(m, r1);
+ else ScheduleNextCacheCheckTime(m, slot, r1->DelayDelivery);
+ }
+ }
+
+ // If we have not consumed the NSEC records yet e.g., just refreshing the cache,
+ // update them now for future validations.
+ if (NSECRecords && NSECCachePtr)
+ {
+ LogInfo("mDNSCoreReceieveResponse: Updating NSEC records in %s", CRDisplayString(m, NSECCachePtr));
+ if (!AddNSECSForCacheRecord(m, NSECRecords, NSECCachePtr, rcode))
+ {
+ LogInfo("mDNSCoreReceiveResponse: AddNSECSForCacheRecord failed to add NSEC for %s", CRDisplayString(m, NSECCachePtr));
+ FreeNSECRecords(m, NSECRecords);
+ }
+ NSECRecords = mDNSNULL;
+ NSECCachePtr = mDNSNULL;
+ }
+
+ // If there is at least one answer and we did not create RRSIGs and there was a
+ // ValidatingResponse question waiting for this response, give a hint that no RRSIGs
+ // were created. We don't need to give a hint:
+ //
+ // - if we have no answers, the mDNSCoreReceiveNoUnicastAnswers below should
+ // generate a negative response
+ //
+ // - if we have NSECRecords, it means we might have a potential proof for
+ // non-existence of name that we are looking for
+ //
+ if (response->h.numAnswers && !rrsigsCreated && DNSSECQuestion && !NSECRecords)
+ mDNSCoreReceiveNoDNSSECAnswers(m, response, end, dstaddr, dstport, InterfaceID);
+
+ // See if we need to generate negative cache entries for unanswered unicast questions
+ mDNSCoreReceiveNoUnicastAnswers(m, response, end, dstaddr, dstport, InterfaceID, LLQType, rcode, NSECRecords);
+
+ if (McastNSEC3Records)
+ {
+ debugf("mDNSCoreReceiveResponse: McastNSEC3Records not used");
+ FreeNSECRecords(m, McastNSEC3Records);
+ }
+}
// ScheduleWakeup causes all proxy records with WakeUp.HMAC matching mDNSEthAddr 'e' to be deregistered, causing
// multiple wakeup magic packets to be sent if appropriate, and all records to be ultimately freed after a few seconds.
// ScheduleWakeup must be called with the lock held (ScheduleWakeupForList uses mDNS_Deregister_internal)
mDNSlocal void ScheduleWakeupForList(mDNS *const m, mDNSInterfaceID InterfaceID, mDNSEthAddr *e, AuthRecord *const thelist)
- {
- // We don't need to use the m->CurrentRecord mechanism here because the target HMAC is nonzero,
- // so all we're doing is marking the record to generate a few wakeup packets
- AuthRecord *rr;
- if (!e->l[0]) { LogMsg("ScheduleWakeupForList ERROR: Target HMAC is zero"); return; }
- for (rr = thelist; rr; rr = rr->next)
- if (rr->resrec.InterfaceID == InterfaceID && rr->resrec.RecordType != kDNSRecordTypeDeregistering && mDNSSameEthAddress(&rr->WakeUp.HMAC, e))
- {
- LogInfo("ScheduleWakeupForList: Scheduling wakeup packets for %s", ARDisplayString(m, rr));
- mDNS_Deregister_internal(m, rr, mDNS_Dereg_normal);
- }
- }
+{
+ // We need to use the m->CurrentRecord mechanism here when dealing with DuplicateRecords list as
+ // mDNS_Deregister_internal deregisters duplicate records immediately as they are not used
+ // to send wakeups or goodbyes. See the comment in that function for more details. To keep it
+ // simple, we use the same mechanism for both lists.
+ if (!e->l[0])
+ {
+ LogMsg("ScheduleWakeupForList ERROR: Target HMAC is zero");
+ return;
+ }
+ m->CurrentRecord = thelist;
+ while (m->CurrentRecord)
+ {
+ AuthRecord *const rr = m->CurrentRecord;
+ if (rr->resrec.InterfaceID == InterfaceID && rr->resrec.RecordType != kDNSRecordTypeDeregistering && mDNSSameEthAddress(&rr->WakeUp.HMAC, e))
+ {
+ LogInfo("ScheduleWakeupForList: Scheduling wakeup packets for %s", ARDisplayString(m, rr));
+ mDNS_Deregister_internal(m, rr, mDNS_Dereg_normal);
+ }
+ if (m->CurrentRecord == rr) // If m->CurrentRecord was not advanced for us, do it now
+ m->CurrentRecord = rr->next;
+ }
+}
mDNSlocal void ScheduleWakeup(mDNS *const m, mDNSInterfaceID InterfaceID, mDNSEthAddr *e)
- {
- if (!e->l[0]) { LogMsg("ScheduleWakeup ERROR: Target HMAC is zero"); return; }
- ScheduleWakeupForList(m, InterfaceID, e, m->DuplicateRecords);
- ScheduleWakeupForList(m, InterfaceID, e, m->ResourceRecords);
- }
+{
+ if (!e->l[0]) { LogMsg("ScheduleWakeup ERROR: Target HMAC is zero"); return; }
+ ScheduleWakeupForList(m, InterfaceID, e, m->DuplicateRecords);
+ ScheduleWakeupForList(m, InterfaceID, e, m->ResourceRecords);
+}
mDNSlocal void SPSRecordCallback(mDNS *const m, AuthRecord *const ar, mStatus result)
- {
- if (result && result != mStatus_MemFree)
- LogInfo("SPS Callback %d %s", result, ARDisplayString(m, ar));
-
- if (result == mStatus_NameConflict)
- {
- mDNS_Lock(m);
- LogMsg("%-7s Conflicting mDNS -- waking %.6a %s", InterfaceNameForID(m, ar->resrec.InterfaceID), &ar->WakeUp.HMAC, ARDisplayString(m, ar));
- if (ar->WakeUp.HMAC.l[0])
- {
- SendWakeup(m, ar->resrec.InterfaceID, &ar->WakeUp.IMAC, &ar->WakeUp.password); // Send one wakeup magic packet
- ScheduleWakeup(m, ar->resrec.InterfaceID, &ar->WakeUp.HMAC); // Schedule all other records with the same owner to be woken
- }
- mDNS_Unlock(m);
- }
-
- if (result == mStatus_NameConflict || result == mStatus_MemFree)
- {
- m->ProxyRecords--;
- mDNSPlatformMemFree(ar);
- mDNS_UpdateAllowSleep(m);
- }
- }
+{
+ if (result && result != mStatus_MemFree)
+ LogInfo("SPS Callback %d %s", result, ARDisplayString(m, ar));
+
+ if (result == mStatus_NameConflict)
+ {
+ mDNS_Lock(m);
+ LogMsg("%-7s Conflicting mDNS -- waking %.6a %s", InterfaceNameForID(m, ar->resrec.InterfaceID), &ar->WakeUp.HMAC, ARDisplayString(m, ar));
+ if (ar->WakeUp.HMAC.l[0])
+ {
+ SendWakeup(m, ar->resrec.InterfaceID, &ar->WakeUp.IMAC, &ar->WakeUp.password); // Send one wakeup magic packet
+ ScheduleWakeup(m, ar->resrec.InterfaceID, &ar->WakeUp.HMAC); // Schedule all other records with the same owner to be woken
+ }
+ mDNS_Unlock(m);
+ }
+
+ if (result == mStatus_NameConflict || result == mStatus_MemFree)
+ {
+ m->ProxyRecords--;
+ mDNSPlatformMemFree(ar);
+ mDNS_UpdateAllowSleep(m);
+ }
+}
+
+mDNSlocal mDNSu8 *GetValueForMACAddr(mDNSu8 *ptr, mDNSu8 *limit, mDNSEthAddr *eth)
+{
+ int i;
+ mDNSs8 hval = 0;
+ int colons = 0;
+ mDNSu8 val = 0;
+
+ for (i = 0; ptr < limit && *ptr != ' ' && i < 17; i++, ptr++)
+ {
+ hval = HexVal(*ptr);
+ if (hval != -1)
+ {
+ val <<= 4;
+ val |= hval;
+ }
+ else if (*ptr == ':')
+ {
+ eth->b[colons] = val;
+ colons++;
+ val = 0;
+ }
+ }
+ if (colons != 5)
+ {
+ LogMsg("GetValueForMACAddr: Address malformed colons %d", colons);
+ return mDNSNULL;
+ }
+ eth->b[colons] = val;
+ return ptr;
+}
+
+mDNSlocal mDNSu8 *GetValueForIPv6Addr(mDNSu8 *ptr, mDNSu8 *limit, mDNSv6Addr *v6)
+{
+ int hval;
+ int value;
+ int numBytes;
+ int digitsProcessed;
+ int zeroFillStart;
+ int numColons;
+ mDNSu8 v6addr[16];
+
+ // RFC 3513: Section 2.2 specifies IPv6 presentation format. The following parsing
+ // handles both (1) and (2) and does not handle embedded IPv4 addresses.
+ //
+ // First forms a address in "v6addr", then expands to fill the zeroes in and returns
+ // the result in "v6"
+
+ numColons = numBytes = value = digitsProcessed = zeroFillStart = 0;
+ while (ptr < limit && *ptr != ' ')
+ {
+ hval = HexVal(*ptr);
+ if (hval != -1)
+ {
+ value <<= 4;
+ value |= hval;
+ digitsProcessed = 1;
+ }
+ else if (*ptr == ':')
+ {
+ if (!digitsProcessed)
+ {
+ // If we have already seen a "::", we should not see one more. Handle the special
+ // case of "::"
+ if (numColons)
+ {
+ // if we never filled any bytes and the next character is space (we have reached the end)
+ // we are done
+ if (!numBytes && (ptr + 1) < limit && *(ptr + 1) == ' ')
+ {
+ mDNSPlatformMemZero(v6->b, 16);
+ return ptr + 1;
+ }
+ LogMsg("GetValueForIPv6Addr: zeroFillStart non-zero %d", zeroFillStart);
+ return mDNSNULL;
+ }
+
+ // We processed "::". We need to fill zeroes later. For now, mark the
+ // point where we will start filling zeroes from.
+ zeroFillStart = numBytes;
+ numColons++;
+ }
+ else if ((ptr + 1) < limit && *(ptr + 1) == ' ')
+ {
+ // We have a trailing ":" i.e., no more characters after ":"
+ LogMsg("GetValueForIPv6Addr: Trailing colon");
+ return mDNSNULL;
+ }
+ else
+ {
+ // For a fully expanded IPv6 address, we fill the 14th and 15th byte outside of this while
+ // loop below as there is no ":" at the end. Hence, the last two bytes that can possibly
+ // filled here is 12 and 13.
+ if (numBytes > 13) { LogMsg("GetValueForIPv6Addr:1: numBytes is %d", numBytes); return mDNSNULL; }
+
+ v6addr[numBytes++] = (mDNSu8) ((value >> 8) & 0xFF);
+ v6addr[numBytes++] = (mDNSu8) (value & 0xFF);
+ digitsProcessed = value = 0;
+
+ // Make sure that we did not fill the 13th and 14th byte above
+ if (numBytes > 14) { LogMsg("GetValueForIPv6Addr:2: numBytes is %d", numBytes); return mDNSNULL; }
+ }
+ }
+ ptr++;
+ }
+
+ // We should be processing the last set of bytes following the last ":" here
+ if (!digitsProcessed)
+ {
+ LogMsg("GetValueForIPv6Addr: no trailing bytes after colon, numBytes is %d", numBytes);
+ return mDNSNULL;
+ }
+
+ if (numBytes > 14) { LogMsg("GetValueForIPv6Addr:3: numBytes is %d", numBytes); return mDNSNULL; }
+ v6addr[numBytes++] = (mDNSu8) ((value >> 8) & 0xFF);
+ v6addr[numBytes++] = (mDNSu8) (value & 0xFF);
+
+ if (zeroFillStart)
+ {
+ int i, j, n;
+ for (i = 0; i < zeroFillStart; i++)
+ v6->b[i] = v6addr[i];
+ for (j = i, n = 0; n < 16 - numBytes; j++, n++)
+ v6->b[j] = 0;
+ for (; j < 16; i++, j++)
+ v6->b[j] = v6addr[i];
+ }
+ else if (numBytes == 16)
+ mDNSPlatformMemCopy(v6->b, v6addr, 16);
+ else
+ {
+ LogMsg("GetValueForIPv6addr: Not enough bytes for IPv6 address, numBytes is %d", numBytes);
+ return mDNSNULL;
+ }
+ return ptr;
+}
+
+mDNSlocal mDNSu8 *GetValueForIPv4Addr(mDNSu8 *ptr, mDNSu8 *limit, mDNSv4Addr *v4)
+{
+ mDNSu32 val;
+ int dots = 0;
+ val = 0;
+
+ for ( ; ptr < limit && *ptr != ' '; ptr++)
+ {
+ if (*ptr >= '0' && *ptr <= '9')
+ val = val * 10 + *ptr - '0';
+ else if (*ptr == '.')
+ {
+ v4->b[dots++] = val;
+ val = 0;
+ }
+ else
+ {
+ // We have a zero at the end and if we reached that, then we are done.
+ if (*ptr == 0 && ptr == limit - 1 && dots == 3)
+ {
+ v4->b[dots] = val;
+ return ptr + 1;
+ }
+ else { LogMsg("GetValueForIPv4Addr: something wrong ptr(%p) %c, limit %p, dots %d", ptr, *ptr, limit, dots); return mDNSNULL; }
+ }
+ }
+ if (dots != 3) { LogMsg("GetValueForIPv4Addr: Address malformed dots %d", dots); return mDNSNULL; }
+ v4->b[dots] = val;
+ return ptr;
+}
+
+mDNSlocal mDNSu8 *GetValueForKeepalive(mDNSu8 *ptr, mDNSu8 *limit, mDNSu32 *value)
+{
+ mDNSu32 val;
+
+ val = 0;
+ for ( ; ptr < limit && *ptr != ' '; ptr++)
+ {
+ if (*ptr < '0' || *ptr > '9')
+ {
+ // We have a zero at the end and if we reached that, then we are done.
+ if (*ptr == 0 && ptr == limit - 1)
+ {
+ *value = val;
+ return ptr + 1;
+ }
+ else { LogMsg("GetValueForKeepalive: *ptr %d, ptr %p, limit %p, ptr +1 %d", *ptr, ptr, limit, *(ptr + 1)); return mDNSNULL; }
+ }
+ val = val * 10 + *ptr - '0';
+ }
+ *value = val;
+ return ptr;
+}
+
+mDNSlocal void mDNS_ExtractKeepaliveInfo(AuthRecord *ar, mDNSu32 *timeout, mDNSAddr *laddr, mDNSAddr *raddr, mDNSEthAddr *eth, mDNSu32 *seq,
+ mDNSu32 *ack, mDNSIPPort *lport, mDNSIPPort *rport, mDNSu16 *win)
+{
+ if (ar->resrec.rrtype != kDNSType_NULL)
+ return;
+
+ if (mDNS_KeepaliveRecord(&ar->resrec))
+ {
+ int len = ar->resrec.rdlength;
+ mDNSu8 *ptr = &ar->resrec.rdata->u.txt.c[1];
+ mDNSu8 *limit = ptr + len - 1; // Exclude the first byte that is the length
+ mDNSu32 value = 0;
+
+ while (ptr < limit)
+ {
+ mDNSu8 param = *ptr;
+ ptr += 2; // Skip the letter and the "="
+ if (param == 'h')
+ {
+ laddr->type = mDNSAddrType_IPv4;
+ ptr = GetValueForIPv4Addr(ptr, limit, &laddr->ip.v4);
+ }
+ else if (param == 'd')
+ {
+ raddr->type = mDNSAddrType_IPv4;
+ ptr = GetValueForIPv4Addr(ptr, limit, &raddr->ip.v4);
+ }
+ if (param == 'H')
+ {
+ laddr->type = mDNSAddrType_IPv6;
+ ptr = GetValueForIPv6Addr(ptr, limit, &laddr->ip.v6);
+ }
+ else if (param == 'D')
+ {
+ raddr->type = mDNSAddrType_IPv6;
+ ptr = GetValueForIPv6Addr(ptr, limit, &raddr->ip.v6);
+ }
+ else if (param == 'm')
+ {
+ ptr = GetValueForMACAddr(ptr, limit, eth);
+ }
+ else
+ {
+ ptr = GetValueForKeepalive(ptr, limit, &value);
+ }
+ if (!ptr) { LogMsg("mDNS_ExtractKeepaliveInfo: Cannot parse\n"); return; }
+
+ // Extract everything in network order so that it is easy for sending a keepalive and also
+ // for matching incoming TCP packets
+ switch (param)
+ {
+ case 't':
+ *timeout = value;
+ //if (*timeout < 120) *timeout = 120;
+ break;
+ case 'h':
+ case 'H':
+ case 'd':
+ case 'D':
+ case 'm':
+ case 'i':
+ case 'c':
+ break;
+ case 'l':
+ lport->NotAnInteger = swap16((mDNSu16)value);
+ break;
+ case 'r':
+ rport->NotAnInteger = swap16((mDNSu16)value);
+ break;
+ case 's':
+ *seq = swap32(value);
+ break;
+ case 'a':
+ *ack = swap32(value);
+ break;
+ case 'w':
+ *win = swap16((mDNSu16)value);
+ break;
+ default:
+ LogMsg("mDNS_ExtractKeepaliveInfo: unknown value %c\n", param);
+ ptr = limit;
+ break;
+ }
+ ptr++; // skip the space
+ }
+ }
+}
+
+// Matches the proxied auth records to the incoming TCP packet and returns the match and its sequence and ack in "rseq" and "rack" so that
+// the clients need not retrieve this information from the auth record again.
+mDNSlocal AuthRecord* mDNS_MatchKeepaliveInfo(mDNS *const m, const mDNSAddr* pladdr, const mDNSAddr* praddr, const mDNSIPPort plport,
+ const mDNSIPPort prport, mDNSu32 *rseq, mDNSu32 *rack)
+{
+ AuthRecord *ar;
+ mDNSAddr laddr, raddr;
+ mDNSEthAddr eth;
+ mDNSIPPort lport, rport;
+ mDNSu32 timeout, seq, ack;
+ mDNSu16 win;
+
+ for (ar = m->ResourceRecords; ar; ar=ar->next)
+ {
+ timeout = seq = ack = 0;
+ win = 0;
+ laddr = raddr = zeroAddr;
+ lport = rport = zeroIPPort;
+
+ if (!ar->WakeUp.HMAC.l[0]) continue;
+
+ mDNS_ExtractKeepaliveInfo(ar, &timeout, &laddr, &raddr, ð, &seq, &ack, &lport, &rport, &win);
+
+ // Did we parse correctly ?
+ if (!timeout || mDNSAddressIsZero(&laddr) || mDNSAddressIsZero(&raddr) || !seq || !ack || mDNSIPPortIsZero(lport) || mDNSIPPortIsZero(rport) || !win)
+ {
+ debugf("mDNS_MatchKeepaliveInfo: not a valid record %s for keepalive", ARDisplayString(m, ar));
+ continue;
+ }
+
+ debugf("mDNS_MatchKeepaliveInfo: laddr %#a pladdr %#a, raddr %#a praddr %#a, lport %d plport %d, rport %d prport %d",
+ &laddr, pladdr, &raddr, praddr, mDNSVal16(lport), mDNSVal16(plport), mDNSVal16(rport), mDNSVal16(prport));
+
+ // Does it match the incoming TCP packet ?
+ if (mDNSSameAddress(&laddr, pladdr) && mDNSSameAddress(&raddr, praddr) && mDNSSameIPPort(lport, plport) && mDNSSameIPPort(rport, prport))
+ {
+ // returning in network order
+ *rseq = seq;
+ *rack = ack;
+ return ar;
+ }
+ }
+ return mDNSNULL;
+}
+
+mDNSlocal void mDNS_SendKeepalives(mDNS *const m)
+{
+ AuthRecord *ar;
+
+ for (ar = m->ResourceRecords; ar; ar=ar->next)
+ {
+ mDNSu32 timeout, seq, ack;
+ mDNSu16 win;
+ mDNSAddr laddr, raddr;
+ mDNSEthAddr eth;
+ mDNSIPPort lport, rport;
+
+ timeout = seq = ack = 0;
+ win = 0;
+
+ laddr = raddr = zeroAddr;
+ lport = rport = zeroIPPort;
+
+ if (!ar->WakeUp.HMAC.l[0]) continue;
+
+ mDNS_ExtractKeepaliveInfo(ar, &timeout, &laddr, &raddr, ð, &seq, &ack, &lport, &rport, &win);
+
+ if (!timeout || mDNSAddressIsZero(&laddr) || mDNSAddressIsZero(&raddr) || !seq || !ack || mDNSIPPortIsZero(lport) || mDNSIPPortIsZero(rport) || !win)
+ {
+ debugf("mDNS_SendKeepalives: not a valid record %s for keepalive", ARDisplayString(m, ar));
+ continue;
+ }
+ LogMsg("mDNS_SendKeepalives: laddr %#a raddr %#a lport %d rport %d", &laddr, &raddr, mDNSVal16(lport), mDNSVal16(rport));
+
+ // When we receive a proxy update, we set KATimeExpire to zero so that we always send a keepalive
+ // immediately (to detect any potential problems). After that we always set it to a non-zero value.
+ if (!ar->KATimeExpire || (m->timenow - ar->KATimeExpire >= 0))
+ {
+ mDNSPlatformSendKeepalive(&laddr, &raddr, &lport, &rport, seq, ack, win);
+ ar->KATimeExpire = NonZeroTime(m->timenow + timeout * mDNSPlatformOneSecond);
+ }
+ if (m->NextScheduledKA - ar->KATimeExpire > 0)
+ m->NextScheduledKA = ar->KATimeExpire;
+ }
+}
+
+mDNSlocal void mDNS_SendKeepaliveACK(mDNS *const m, AuthRecord *ar)
+{
+ if (ar != mDNSNULL)
+ {
+ LogInfo("mDNS_SendKeepalivesACK: AuthRecord is NULL");
+ return;
+ }
+ mDNSu32 timeout, seq, ack;
+ mDNSu16 win;
+ mDNSAddr laddr, raddr;
+ mDNSEthAddr eth;
+ mDNSIPPort lport, rport;
+
+ timeout = seq = ack = 0;
+ win = 0;
+
+ laddr = raddr = zeroAddr;
+ lport = rport = zeroIPPort;
+
+ mDNS_ExtractKeepaliveInfo(ar, &timeout, &laddr, &raddr, ð, &seq, &ack, &lport, &rport, &win);
+
+ if (!timeout || mDNSAddressIsZero(&laddr) || mDNSAddressIsZero(&raddr) || !seq || !ack || mDNSIPPortIsZero(lport) || mDNSIPPortIsZero(rport) || !win)
+ {
+ LogInfo("mDNS_SendKeepaliveACK: not a valid record %s for keepalive", ARDisplayString(m, ar));
+ return;
+ }
+ LogMsg("mDNS_SendKeepaliveACK: laddr %#a raddr %#a lport %d rport %d", &laddr, &raddr, mDNSVal16(lport), mDNSVal16(rport));
+ mDNSPlatformSendKeepalive(&laddr, &raddr, &lport, &rport, seq, ack, win);
+}
mDNSlocal void mDNSCoreReceiveUpdate(mDNS *const m,
- const DNSMessage *const msg, const mDNSu8 *end,
- const mDNSAddr *srcaddr, const mDNSIPPort srcport, const mDNSAddr *dstaddr, mDNSIPPort dstport,
- const mDNSInterfaceID InterfaceID)
- {
- int i;
- AuthRecord opt;
- mDNSu8 *p = m->omsg.data;
- OwnerOptData owner = zeroOwner; // Need to zero this, so we'll know if this Update packet was missing its Owner option
- mDNSu32 updatelease = 0;
- const mDNSu8 *ptr;
-
- LogSPS("Received Update from %#-15a:%-5d to %#-15a:%-5d on 0x%p with "
- "%2d Question%s %2d Answer%s %2d Authorit%s %2d Additional%s %d bytes",
- srcaddr, mDNSVal16(srcport), dstaddr, mDNSVal16(dstport), InterfaceID,
- msg->h.numQuestions, msg->h.numQuestions == 1 ? ", " : "s,",
- msg->h.numAnswers, msg->h.numAnswers == 1 ? ", " : "s,",
- msg->h.numAuthorities, msg->h.numAuthorities == 1 ? "y, " : "ies,",
- msg->h.numAdditionals, msg->h.numAdditionals == 1 ? " " : "s", end - msg->data);
-
- if (!InterfaceID || !m->SPSSocket || !mDNSSameIPPort(dstport, m->SPSSocket->port)) return;
-
- if (mDNS_PacketLoggingEnabled)
- DumpPacket(m, mStatus_NoError, mDNSfalse, "UDP", srcaddr, srcport, dstaddr, dstport, msg, end);
-
- ptr = LocateOptRR(msg, end, DNSOpt_LeaseData_Space + DNSOpt_OwnerData_ID_Space);
- if (ptr)
- {
- ptr = GetLargeResourceRecord(m, msg, ptr, end, 0, kDNSRecordTypePacketAdd, &m->rec);
- if (ptr && m->rec.r.resrec.RecordType != kDNSRecordTypePacketNegative && m->rec.r.resrec.rrtype == kDNSType_OPT)
- {
- const rdataOPT *o;
- const rdataOPT *const e = (const rdataOPT *)&m->rec.r.resrec.rdata->u.data[m->rec.r.resrec.rdlength];
- for (o = &m->rec.r.resrec.rdata->u.opt[0]; o < e; o++)
- {
- if (o->opt == kDNSOpt_Lease) updatelease = o->u.updatelease;
- else if (o->opt == kDNSOpt_Owner && o->u.owner.vers == 0) owner = o->u.owner;
- }
- }
- m->rec.r.resrec.RecordType = 0; // Clear RecordType to show we're not still using it
- }
-
- InitializeDNSMessage(&m->omsg.h, msg->h.id, UpdateRespFlags);
-
- if (!updatelease || !owner.HMAC.l[0])
- {
- static int msgs = 0;
- if (msgs < 100)
- {
- msgs++;
- LogMsg("Refusing sleep proxy registration from %#a:%d:%s%s", srcaddr, mDNSVal16(srcport),
- !updatelease ? " No lease" : "", !owner.HMAC.l[0] ? " No owner" : "");
- }
- m->omsg.h.flags.b[1] |= kDNSFlag1_RC_FormErr;
- }
- else if (m->ProxyRecords + msg->h.mDNS_numUpdates > MAX_PROXY_RECORDS)
- {
- static int msgs = 0;
- if (msgs < 100)
- {
- msgs++;
- LogMsg("Refusing sleep proxy registration from %#a:%d: Too many records %d + %d = %d > %d", srcaddr, mDNSVal16(srcport),
- m->ProxyRecords, msg->h.mDNS_numUpdates, m->ProxyRecords + msg->h.mDNS_numUpdates, MAX_PROXY_RECORDS);
- }
- m->omsg.h.flags.b[1] |= kDNSFlag1_RC_Refused;
- }
- else
- {
- LogSPS("Received Update for H-MAC %.6a I-MAC %.6a Password %.6a seq %d", &owner.HMAC, &owner.IMAC, &owner.password, owner.seq);
-
- if (updatelease > 24 * 60 * 60)
- updatelease = 24 * 60 * 60;
-
- if (updatelease > 0x40000000UL / mDNSPlatformOneSecond)
- updatelease = 0x40000000UL / mDNSPlatformOneSecond;
-
- ptr = LocateAuthorities(msg, end);
- for (i = 0; i < msg->h.mDNS_numUpdates && ptr && ptr < end; i++)
- {
- ptr = GetLargeResourceRecord(m, msg, ptr, end, InterfaceID, kDNSRecordTypePacketAuth, &m->rec);
- if (ptr && m->rec.r.resrec.RecordType != kDNSRecordTypePacketNegative)
- {
- mDNSu16 RDLengthMem = GetRDLengthMem(&m->rec.r.resrec);
- AuthRecord *ar = mDNSPlatformMemAllocate(sizeof(AuthRecord) - sizeof(RDataBody) + RDLengthMem);
- if (!ar) { m->omsg.h.flags.b[1] |= kDNSFlag1_RC_Refused; break; }
- else
- {
- mDNSu8 RecordType = m->rec.r.resrec.RecordType & kDNSRecordTypePacketUniqueMask ? kDNSRecordTypeUnique : kDNSRecordTypeShared;
- m->rec.r.resrec.rrclass &= ~kDNSClass_UniqueRRSet;
- ClearIdenticalProxyRecords(m, &owner, m->DuplicateRecords); // Make sure we don't have any old stale duplicates of this record
- ClearIdenticalProxyRecords(m, &owner, m->ResourceRecords);
- mDNS_SetupResourceRecord(ar, mDNSNULL, InterfaceID, m->rec.r.resrec.rrtype, m->rec.r.resrec.rroriginalttl, RecordType, AuthRecordAny, SPSRecordCallback, ar);
- AssignDomainName(&ar->namestorage, m->rec.r.resrec.name);
- ar->resrec.rdlength = GetRDLength(&m->rec.r.resrec, mDNSfalse);
- ar->resrec.rdata->MaxRDLength = RDLengthMem;
- mDNSPlatformMemCopy(ar->resrec.rdata->u.data, m->rec.r.resrec.rdata->u.data, RDLengthMem);
- ar->ForceMCast = mDNStrue;
- ar->WakeUp = owner;
- if (m->rec.r.resrec.rrtype == kDNSType_PTR)
- {
- mDNSs32 t = ReverseMapDomainType(m->rec.r.resrec.name);
- if (t == mDNSAddrType_IPv4) GetIPv4FromName(&ar->AddressProxy, m->rec.r.resrec.name);
- else if (t == mDNSAddrType_IPv6) GetIPv6FromName(&ar->AddressProxy, m->rec.r.resrec.name);
- debugf("mDNSCoreReceiveUpdate: PTR %d %d %#a %s", t, ar->AddressProxy.type, &ar->AddressProxy, ARDisplayString(m, ar));
- if (ar->AddressProxy.type) SetSPSProxyListChanged(InterfaceID);
- }
- ar->TimeRcvd = m->timenow;
- ar->TimeExpire = m->timenow + updatelease * mDNSPlatformOneSecond;
- if (m->NextScheduledSPS - ar->TimeExpire > 0)
- m->NextScheduledSPS = ar->TimeExpire;
- mDNS_Register_internal(m, ar);
- // Unsolicited Neighbor Advertisements (RFC 2461 Section 7.2.6) give us fast address cache updating,
- // but some older IPv6 clients get confused by them, so for now we don't send them. Without Unsolicited
- // Neighbor Advertisements we have to rely on Neighbor Unreachability Detection instead, which is slower.
- // Given this, we'll do our best to wake for existing IPv6 connections, but we don't want to encourage
- // new ones for sleeping clients, so we'll we send deletions for our SPS clients' AAAA records.
- if (m->KnownBugs & mDNS_KnownBug_LimitedIPv6)
- if (ar->resrec.rrtype == kDNSType_AAAA) ar->resrec.rroriginalttl = 0;
- m->ProxyRecords++;
- mDNS_UpdateAllowSleep(m);
- LogSPS("SPS Registered %4d %X %s", m->ProxyRecords, RecordType, ARDisplayString(m,ar));
- }
- }
- m->rec.r.resrec.RecordType = 0; // Clear RecordType to show we're not still using it
- }
-
- if (m->omsg.h.flags.b[1] & kDNSFlag1_RC_Mask)
- {
- LogMsg("Refusing sleep proxy registration from %#a:%d: Out of memory", srcaddr, mDNSVal16(srcport));
- ClearProxyRecords(m, &owner, m->DuplicateRecords);
- ClearProxyRecords(m, &owner, m->ResourceRecords);
- }
- else
- {
- mDNS_SetupResourceRecord(&opt, mDNSNULL, mDNSInterface_Any, kDNSType_OPT, kStandardTTL, kDNSRecordTypeKnownUnique, AuthRecordAny, mDNSNULL, mDNSNULL);
- opt.resrec.rrclass = NormalMaxDNSMessageData;
- opt.resrec.rdlength = sizeof(rdataOPT); // One option in this OPT record
- opt.resrec.rdestimate = sizeof(rdataOPT);
- opt.resrec.rdata->u.opt[0].opt = kDNSOpt_Lease;
- opt.resrec.rdata->u.opt[0].u.updatelease = updatelease;
- p = PutResourceRecordTTLWithLimit(&m->omsg, p, &m->omsg.h.numAdditionals, &opt.resrec, opt.resrec.rroriginalttl, m->omsg.data + AbsoluteMaxDNSMessageData);
- }
- }
-
- if (p) mDNSSendDNSMessage(m, &m->omsg, p, InterfaceID, m->SPSSocket, srcaddr, srcport, mDNSNULL, mDNSNULL);
- }
-
-mDNSlocal void mDNSCoreReceiveUpdateR(mDNS *const m, const DNSMessage *const msg, const mDNSu8 *end, const mDNSInterfaceID InterfaceID)
- {
- if (InterfaceID)
- {
- mDNSu32 updatelease = 60 * 60; // If SPS fails to indicate lease time, assume one hour
- const mDNSu8 *ptr = LocateOptRR(msg, end, DNSOpt_LeaseData_Space);
- if (ptr)
- {
- ptr = GetLargeResourceRecord(m, msg, ptr, end, 0, kDNSRecordTypePacketAdd, &m->rec);
- if (ptr && m->rec.r.resrec.RecordType != kDNSRecordTypePacketNegative && m->rec.r.resrec.rrtype == kDNSType_OPT)
- {
- const rdataOPT *o;
- const rdataOPT *const e = (const rdataOPT *)&m->rec.r.resrec.rdata->u.data[m->rec.r.resrec.rdlength];
- for (o = &m->rec.r.resrec.rdata->u.opt[0]; o < e; o++)
- if (o->opt == kDNSOpt_Lease)
- {
- updatelease = o->u.updatelease;
- LogSPS("Sleep Proxy granted lease time %4d seconds", updatelease);
- }
- }
- m->rec.r.resrec.RecordType = 0; // Clear RecordType to show we're not still using it
- }
-
- if (m->CurrentRecord)
- LogMsg("mDNSCoreReceiveUpdateR ERROR m->CurrentRecord already set %s", ARDisplayString(m, m->CurrentRecord));
- m->CurrentRecord = m->ResourceRecords;
- while (m->CurrentRecord)
- {
- AuthRecord *const rr = m->CurrentRecord;
- if (rr->resrec.InterfaceID == InterfaceID || (!rr->resrec.InterfaceID && (rr->ForceMCast || IsLocalDomain(rr->resrec.name))))
- if (mDNSSameOpaque16(rr->updateid, msg->h.id))
- {
- rr->updateid = zeroID;
- rr->expire = NonZeroTime(m->timenow + updatelease * mDNSPlatformOneSecond);
- LogSPS("Sleep Proxy %s record %5d %s", rr->WakeUp.HMAC.l[0] ? "transferred" : "registered", updatelease, ARDisplayString(m,rr));
- if (rr->WakeUp.HMAC.l[0])
- {
- rr->WakeUp.HMAC = zeroEthAddr; // Clear HMAC so that mDNS_Deregister_internal doesn't waste packets trying to wake this host
- rr->RequireGoodbye = mDNSfalse; // and we don't want to send goodbye for it
- mDNS_Deregister_internal(m, rr, mDNS_Dereg_normal);
- }
- }
- // Mustn't advance m->CurrentRecord until *after* mDNS_Deregister_internal, because
- // new records could have been added to the end of the list as a result of that call.
- if (m->CurrentRecord == rr) // If m->CurrentRecord was not advanced for us, do it now
- m->CurrentRecord = rr->next;
- }
- }
- // If we were waiting to go to sleep, then this SPS registration or wide-area record deletion
- // may have been the thing we were waiting for, so schedule another check to see if we can sleep now.
- if (m->SleepLimit) m->NextScheduledSPRetry = m->timenow;
- }
+ const DNSMessage *const msg, const mDNSu8 *end,
+ const mDNSAddr *srcaddr, const mDNSIPPort srcport, const mDNSAddr *dstaddr, mDNSIPPort dstport,
+ const mDNSInterfaceID InterfaceID)
+{
+ int i;
+ AuthRecord opt;
+ mDNSu8 *p = m->omsg.data;
+ OwnerOptData owner = zeroOwner; // Need to zero this, so we'll know if this Update packet was missing its Owner option
+ mDNSu32 updatelease = 0;
+ const mDNSu8 *ptr;
+
+ LogSPS("Received Update from %#-15a:%-5d to %#-15a:%-5d on 0x%p with "
+ "%2d Question%s %2d Answer%s %2d Authorit%s %2d Additional%s %d bytes",
+ srcaddr, mDNSVal16(srcport), dstaddr, mDNSVal16(dstport), InterfaceID,
+ msg->h.numQuestions, msg->h.numQuestions == 1 ? ", " : "s,",
+ msg->h.numAnswers, msg->h.numAnswers == 1 ? ", " : "s,",
+ msg->h.numAuthorities, msg->h.numAuthorities == 1 ? "y, " : "ies,",
+ msg->h.numAdditionals, msg->h.numAdditionals == 1 ? " " : "s", end - msg->data);
+
+ if (!InterfaceID || !m->SPSSocket || !mDNSSameIPPort(dstport, m->SPSSocket->port)) return;
+
+ if (mDNS_PacketLoggingEnabled)
+ DumpPacket(m, mStatus_NoError, mDNSfalse, "UDP", srcaddr, srcport, dstaddr, dstport, msg, end);
+
+ ptr = LocateOptRR(msg, end, DNSOpt_LeaseData_Space + DNSOpt_OwnerData_ID_Space);
+ if (ptr)
+ {
+ ptr = GetLargeResourceRecord(m, msg, ptr, end, 0, kDNSRecordTypePacketAdd, &m->rec);
+ if (ptr && m->rec.r.resrec.RecordType != kDNSRecordTypePacketNegative && m->rec.r.resrec.rrtype == kDNSType_OPT)
+ {
+ const rdataOPT *o;
+ const rdataOPT *const e = (const rdataOPT *)&m->rec.r.resrec.rdata->u.data[m->rec.r.resrec.rdlength];
+ for (o = &m->rec.r.resrec.rdata->u.opt[0]; o < e; o++)
+ {
+ if (o->opt == kDNSOpt_Lease) updatelease = o->u.updatelease;
+ else if (o->opt == kDNSOpt_Owner && o->u.owner.vers == 0) owner = o->u.owner;
+ }
+ }
+ m->rec.r.resrec.RecordType = 0; // Clear RecordType to show we're not still using it
+ }
+
+ InitializeDNSMessage(&m->omsg.h, msg->h.id, UpdateRespFlags);
+
+ if (!updatelease || !owner.HMAC.l[0])
+ {
+ static int msgs = 0;
+ if (msgs < 100)
+ {
+ msgs++;
+ LogMsg("Refusing sleep proxy registration from %#a:%d:%s%s", srcaddr, mDNSVal16(srcport),
+ !updatelease ? " No lease" : "", !owner.HMAC.l[0] ? " No owner" : "");
+ }
+ m->omsg.h.flags.b[1] |= kDNSFlag1_RC_FormErr;
+ }
+ else if (m->ProxyRecords + msg->h.mDNS_numUpdates > MAX_PROXY_RECORDS)
+ {
+ static int msgs = 0;
+ if (msgs < 100)
+ {
+ msgs++;
+ LogMsg("Refusing sleep proxy registration from %#a:%d: Too many records %d + %d = %d > %d", srcaddr, mDNSVal16(srcport),
+ m->ProxyRecords, msg->h.mDNS_numUpdates, m->ProxyRecords + msg->h.mDNS_numUpdates, MAX_PROXY_RECORDS);
+ }
+ m->omsg.h.flags.b[1] |= kDNSFlag1_RC_Refused;
+ }
+ else
+ {
+ LogSPS("Received Update for H-MAC %.6a I-MAC %.6a Password %.6a seq %d", &owner.HMAC, &owner.IMAC, &owner.password, owner.seq);
+
+ if (updatelease > 24 * 60 * 60)
+ updatelease = 24 * 60 * 60;
+
+ if (updatelease > 0x40000000UL / mDNSPlatformOneSecond)
+ updatelease = 0x40000000UL / mDNSPlatformOneSecond;
+
+ ptr = LocateAuthorities(msg, end);
+
+ // Clear any stale TCP keepalive records that may exist
+ ClearKeepaliveProxyRecords(m, &owner, m->DuplicateRecords, InterfaceID);
+ ClearKeepaliveProxyRecords(m, &owner, m->ResourceRecords, InterfaceID);
+
+ for (i = 0; i < msg->h.mDNS_numUpdates && ptr && ptr < end; i++)
+ {
+ ptr = GetLargeResourceRecord(m, msg, ptr, end, InterfaceID, kDNSRecordTypePacketAuth, &m->rec);
+ if (ptr && m->rec.r.resrec.RecordType != kDNSRecordTypePacketNegative)
+ {
+ mDNSu16 RDLengthMem = GetRDLengthMem(&m->rec.r.resrec);
+ AuthRecord *ar = mDNSPlatformMemAllocate(sizeof(AuthRecord) - sizeof(RDataBody) + RDLengthMem);
+ if (!ar)
+ {
+ m->omsg.h.flags.b[1] |= kDNSFlag1_RC_Refused;
+ break;
+ }
+ else
+ {
+ mDNSu8 RecordType = m->rec.r.resrec.RecordType & kDNSRecordTypePacketUniqueMask ? kDNSRecordTypeUnique : kDNSRecordTypeShared;
+ m->rec.r.resrec.rrclass &= ~kDNSClass_UniqueRRSet;
+ // All stale keepalive records have been flushed prior to this loop.
+ if (!mDNS_KeepaliveRecord(&m->rec.r.resrec))
+ {
+ ClearIdenticalProxyRecords(m, &owner, m->DuplicateRecords); // Make sure we don't have any old stale duplicates of this record
+ ClearIdenticalProxyRecords(m, &owner, m->ResourceRecords);
+ }
+ mDNS_SetupResourceRecord(ar, mDNSNULL, InterfaceID, m->rec.r.resrec.rrtype, m->rec.r.resrec.rroriginalttl, RecordType, AuthRecordAny, SPSRecordCallback, ar);
+ AssignDomainName(&ar->namestorage, m->rec.r.resrec.name);
+ ar->resrec.rdlength = GetRDLength(&m->rec.r.resrec, mDNSfalse);
+ ar->resrec.rdata->MaxRDLength = RDLengthMem;
+ mDNSPlatformMemCopy(ar->resrec.rdata->u.data, m->rec.r.resrec.rdata->u.data, RDLengthMem);
+ ar->ForceMCast = mDNStrue;
+ ar->WakeUp = owner;
+ if (m->rec.r.resrec.rrtype == kDNSType_PTR)
+ {
+ mDNSs32 t = ReverseMapDomainType(m->rec.r.resrec.name);
+ if (t == mDNSAddrType_IPv4) GetIPv4FromName(&ar->AddressProxy, m->rec.r.resrec.name);
+ else if (t == mDNSAddrType_IPv6) GetIPv6FromName(&ar->AddressProxy, m->rec.r.resrec.name);
+ debugf("mDNSCoreReceiveUpdate: PTR %d %d %#a %s", t, ar->AddressProxy.type, &ar->AddressProxy, ARDisplayString(m, ar));
+ if (ar->AddressProxy.type) SetSPSProxyListChanged(InterfaceID);
+ }
+ ar->TimeRcvd = m->timenow;
+ ar->TimeExpire = m->timenow + updatelease * mDNSPlatformOneSecond;
+ if (m->NextScheduledSPS - ar->TimeExpire > 0)
+ m->NextScheduledSPS = ar->TimeExpire;
+ ar->KATimeExpire = 0;
+ mDNS_Register_internal(m, ar);
+
+ m->ProxyRecords++;
+ mDNS_UpdateAllowSleep(m);
+ LogSPS("SPS Registered %4d %X %s", m->ProxyRecords, RecordType, ARDisplayString(m,ar));
+ }
+ }
+ m->rec.r.resrec.RecordType = 0; // Clear RecordType to show we're not still using it
+ }
+
+ if (m->omsg.h.flags.b[1] & kDNSFlag1_RC_Mask)
+ {
+ LogMsg("Refusing sleep proxy registration from %#a:%d: Out of memory", srcaddr, mDNSVal16(srcport));
+ ClearProxyRecords(m, &owner, m->DuplicateRecords);
+ ClearProxyRecords(m, &owner, m->ResourceRecords);
+ }
+ else
+ {
+ mDNS_SetupResourceRecord(&opt, mDNSNULL, mDNSInterface_Any, kDNSType_OPT, kStandardTTL, kDNSRecordTypeKnownUnique, AuthRecordAny, mDNSNULL, mDNSNULL);
+ opt.resrec.rrclass = NormalMaxDNSMessageData;
+ opt.resrec.rdlength = sizeof(rdataOPT); // One option in this OPT record
+ opt.resrec.rdestimate = sizeof(rdataOPT);
+ opt.resrec.rdata->u.opt[0].opt = kDNSOpt_Lease;
+ opt.resrec.rdata->u.opt[0].u.updatelease = updatelease;
+ p = PutResourceRecordTTLWithLimit(&m->omsg, p, &m->omsg.h.numAdditionals, &opt.resrec, opt.resrec.rroriginalttl, m->omsg.data + AbsoluteMaxDNSMessageData);
+ }
+ }
+
+ if (p) mDNSSendDNSMessage(m, &m->omsg, p, InterfaceID, m->SPSSocket, srcaddr, srcport, mDNSNULL, mDNSNULL, mDNSfalse);
+ mDNS_SendKeepalives(m);
+}
+
+mDNSlocal void mDNSCoreReceiveUpdateR(mDNS *const m, const DNSMessage *const msg, const mDNSu8 *end, const mDNSAddr *srcaddr, const mDNSInterfaceID InterfaceID)
+{
+ if (InterfaceID)
+ {
+ mDNSu32 updatelease = 60 * 60; // If SPS fails to indicate lease time, assume one hour
+ const mDNSu8 *ptr = LocateOptRR(msg, end, DNSOpt_LeaseData_Space);
+ if (ptr)
+ {
+ ptr = GetLargeResourceRecord(m, msg, ptr, end, 0, kDNSRecordTypePacketAdd, &m->rec);
+ if (ptr && m->rec.r.resrec.RecordType != kDNSRecordTypePacketNegative && m->rec.r.resrec.rrtype == kDNSType_OPT)
+ {
+ const rdataOPT *o;
+ const rdataOPT *const e = (const rdataOPT *)&m->rec.r.resrec.rdata->u.data[m->rec.r.resrec.rdlength];
+ for (o = &m->rec.r.resrec.rdata->u.opt[0]; o < e; o++)
+ if (o->opt == kDNSOpt_Lease)
+ {
+ updatelease = o->u.updatelease;
+ LogSPS("Sleep Proxy granted lease time %4d seconds, updateid %d, InterfaceID %p", updatelease, mDNSVal16(msg->h.id), InterfaceID);
+ }
+ }
+ m->rec.r.resrec.RecordType = 0; // Clear RecordType to show we're not still using it
+ }
+
+ if (m->CurrentRecord)
+ LogMsg("mDNSCoreReceiveUpdateR ERROR m->CurrentRecord already set %s", ARDisplayString(m, m->CurrentRecord));
+ m->CurrentRecord = m->ResourceRecords;
+ while (m->CurrentRecord)
+ {
+ AuthRecord *const rr = m->CurrentRecord;
+ if (rr->resrec.InterfaceID == InterfaceID || (!rr->resrec.InterfaceID && (rr->ForceMCast || IsLocalDomain(rr->resrec.name))))
+ if (mDNSSameOpaque16(rr->updateid, msg->h.id))
+ {
+ // We successfully completed this record's registration on this "InterfaceID". Clear that bit.
+ // Clear the updateid when we are done sending on all interfaces.
+ mDNSu32 scopeid = mDNSPlatformInterfaceIndexfromInterfaceID(m, InterfaceID, mDNStrue);
+ if (scopeid < (sizeof(rr->updateIntID) * mDNSNBBY))
+ bit_clr_opaque64(rr->updateIntID, scopeid);
+ if (mDNSOpaque64IsZero(&rr->updateIntID))
+ rr->updateid = zeroID;
+ rr->expire = NonZeroTime(m->timenow + updatelease * mDNSPlatformOneSecond);
+ LogSPS("Sleep Proxy %s record %5d 0x%x 0x%x (%d) %s", rr->WakeUp.HMAC.l[0] ? "transferred" : "registered", updatelease, rr->updateIntID.l[1], rr->updateIntID.l[0], mDNSVal16(rr->updateid), ARDisplayString(m,rr));
+ if (rr->WakeUp.HMAC.l[0])
+ {
+ rr->WakeUp.HMAC = zeroEthAddr; // Clear HMAC so that mDNS_Deregister_internal doesn't waste packets trying to wake this host
+ rr->RequireGoodbye = mDNSfalse; // and we don't want to send goodbye for it
+ mDNS_Deregister_internal(m, rr, mDNS_Dereg_normal);
+ }
+ }
+ // Mustn't advance m->CurrentRecord until *after* mDNS_Deregister_internal, because
+ // new records could have been added to the end of the list as a result of that call.
+ if (m->CurrentRecord == rr) // If m->CurrentRecord was not advanced for us, do it now
+ m->CurrentRecord = rr->next;
+ }
+
+ // Update the dynamic store with the IP Address and MAC address of the sleep proxy
+ char *ifname = InterfaceNameForID(m, InterfaceID);
+ mDNSAddr spsaddr;
+ mDNSPlatformMemCopy(&spsaddr, srcaddr, sizeof (mDNSAddr));
+ mDNSPlatformStoreSPSMACAddr(&spsaddr, ifname);
+ }
+ // If we were waiting to go to sleep, then this SPS registration or wide-area record deletion
+ // may have been the thing we were waiting for, so schedule another check to see if we can sleep now.
+ if (m->SleepLimit) m->NextScheduledSPRetry = m->timenow;
+}
mDNSexport void MakeNegativeCacheRecord(mDNS *const m, CacheRecord *const cr,
- const domainname *const name, const mDNSu32 namehash, const mDNSu16 rrtype, const mDNSu16 rrclass, mDNSu32 ttl_seconds, mDNSInterfaceID InterfaceID, DNSServer *dnsserver)
- {
- if (cr == &m->rec.r && m->rec.r.resrec.RecordType)
- {
- LogMsg("MakeNegativeCacheRecord: m->rec appears to be already in use for %s", CRDisplayString(m, &m->rec.r));
+ const domainname *const name, const mDNSu32 namehash, const mDNSu16 rrtype, const mDNSu16 rrclass, mDNSu32 ttl_seconds, mDNSInterfaceID InterfaceID, DNSServer *dnsserver)
+{
+ if (cr == &m->rec.r && m->rec.r.resrec.RecordType)
+ {
+ LogMsg("MakeNegativeCacheRecord: m->rec appears to be already in use for %s", CRDisplayString(m, &m->rec.r));
#if ForceAlerts
- *(long*)0 = 0;
+ *(long*)0 = 0;
#endif
- }
-
- // Create empty resource record
- cr->resrec.RecordType = kDNSRecordTypePacketNegative;
- cr->resrec.InterfaceID = InterfaceID;
- cr->resrec.rDNSServer = dnsserver;
- cr->resrec.name = name; // Will be updated to point to cg->name when we call CreateNewCacheEntry
- cr->resrec.rrtype = rrtype;
- cr->resrec.rrclass = rrclass;
- cr->resrec.rroriginalttl = ttl_seconds;
- cr->resrec.rdlength = 0;
- cr->resrec.rdestimate = 0;
- cr->resrec.namehash = namehash;
- cr->resrec.rdatahash = 0;
- cr->resrec.rdata = (RData*)&cr->smallrdatastorage;
- cr->resrec.rdata->MaxRDLength = 0;
-
- cr->NextInKAList = mDNSNULL;
- cr->TimeRcvd = m->timenow;
- cr->DelayDelivery = 0;
- cr->NextRequiredQuery = m->timenow;
- cr->LastUsed = m->timenow;
- cr->CRActiveQuestion = mDNSNULL;
- cr->UnansweredQueries = 0;
- cr->LastUnansweredTime = 0;
+ }
+
+ // Create empty resource record
+ cr->resrec.RecordType = kDNSRecordTypePacketNegative;
+ cr->resrec.InterfaceID = InterfaceID;
+ cr->resrec.rDNSServer = dnsserver;
+ cr->resrec.name = name; // Will be updated to point to cg->name when we call CreateNewCacheEntry
+ cr->resrec.rrtype = rrtype;
+ cr->resrec.rrclass = rrclass;
+ cr->resrec.rroriginalttl = ttl_seconds;
+ cr->resrec.rdlength = 0;
+ cr->resrec.rdestimate = 0;
+ cr->resrec.namehash = namehash;
+ cr->resrec.rdatahash = 0;
+ cr->resrec.rdata = (RData*)&cr->smallrdatastorage;
+ cr->resrec.rdata->MaxRDLength = 0;
+
+ cr->NextInKAList = mDNSNULL;
+ cr->TimeRcvd = m->timenow;
+ cr->DelayDelivery = 0;
+ cr->NextRequiredQuery = m->timenow;
+ cr->LastUsed = m->timenow;
+ cr->CRActiveQuestion = mDNSNULL;
+ cr->UnansweredQueries = 0;
+ cr->LastUnansweredTime = 0;
#if ENABLE_MULTI_PACKET_QUERY_SNOOPING
- cr->MPUnansweredQ = 0;
- cr->MPLastUnansweredQT = 0;
- cr->MPUnansweredKA = 0;
- cr->MPExpectingKA = mDNSfalse;
+ cr->MPUnansweredQ = 0;
+ cr->MPLastUnansweredQT = 0;
+ cr->MPUnansweredKA = 0;
+ cr->MPExpectingKA = mDNSfalse;
#endif
- cr->NextInCFList = mDNSNULL;
- }
+ cr->NextInCFList = mDNSNULL;
+ cr->nsec = mDNSNULL;
+ cr->soa = mDNSNULL;
+ cr->CRDNSSECQuestion = 0;
+ // Initialize to the basic one and the caller can set it to more
+ // specific based on the response if any
+ cr->responseFlags = ResponseFlags;
+}
mDNSexport void mDNSCoreReceive(mDNS *const m, void *const pkt, const mDNSu8 *const end,
- const mDNSAddr *const srcaddr, const mDNSIPPort srcport, const mDNSAddr *dstaddr, const mDNSIPPort dstport,
- const mDNSInterfaceID InterfaceID)
- {
- mDNSInterfaceID ifid = InterfaceID;
- DNSMessage *msg = (DNSMessage *)pkt;
- const mDNSu8 StdQ = kDNSFlag0_QR_Query | kDNSFlag0_OP_StdQuery;
- const mDNSu8 StdR = kDNSFlag0_QR_Response | kDNSFlag0_OP_StdQuery;
- const mDNSu8 UpdQ = kDNSFlag0_QR_Query | kDNSFlag0_OP_Update;
- const mDNSu8 UpdR = kDNSFlag0_QR_Response | kDNSFlag0_OP_Update;
- mDNSu8 QR_OP;
- mDNSu8 *ptr = mDNSNULL;
- mDNSBool TLS = (dstaddr == (mDNSAddr *)1); // For debug logs: dstaddr = 0 means TCP; dstaddr = 1 means TLS
- if (TLS) dstaddr = mDNSNULL;
+ const mDNSAddr *const srcaddr, const mDNSIPPort srcport, const mDNSAddr *dstaddr, const mDNSIPPort dstport,
+ const mDNSInterfaceID InterfaceID)
+{
+ mDNSInterfaceID ifid = InterfaceID;
+ DNSMessage *msg = (DNSMessage *)pkt;
+ const mDNSu8 StdQ = kDNSFlag0_QR_Query | kDNSFlag0_OP_StdQuery;
+ const mDNSu8 StdR = kDNSFlag0_QR_Response | kDNSFlag0_OP_StdQuery;
+ const mDNSu8 UpdQ = kDNSFlag0_QR_Query | kDNSFlag0_OP_Update;
+ const mDNSu8 UpdR = kDNSFlag0_QR_Response | kDNSFlag0_OP_Update;
+ mDNSu8 QR_OP;
+ mDNSu8 *ptr = mDNSNULL;
+ mDNSBool TLS = (dstaddr == (mDNSAddr *)1); // For debug logs: dstaddr = 0 means TCP; dstaddr = 1 means TLS
+ if (TLS) dstaddr = mDNSNULL;
#ifndef UNICAST_DISABLED
- if (mDNSSameAddress(srcaddr, &m->Router))
- {
+ if (mDNSSameAddress(srcaddr, &m->Router))
+ {
#ifdef _LEGACY_NAT_TRAVERSAL_
- if (mDNSSameIPPort(srcport, SSDPPort) || (m->SSDPSocket && mDNSSameIPPort(dstport, m->SSDPSocket->port)))
- {
- mDNS_Lock(m);
- LNT_ConfigureRouterInfo(m, InterfaceID, pkt, (mDNSu16)(end - (mDNSu8 *)pkt));
- mDNS_Unlock(m);
- return;
- }
+ if (mDNSSameIPPort(srcport, SSDPPort) || (m->SSDPSocket && mDNSSameIPPort(dstport, m->SSDPSocket->port)))
+ {
+ mDNS_Lock(m);
+ LNT_ConfigureRouterInfo(m, InterfaceID, pkt, (mDNSu16)(end - (mDNSu8 *)pkt));
+ mDNS_Unlock(m);
+ return;
+ }
#endif
- if (mDNSSameIPPort(srcport, NATPMPPort))
- {
- mDNS_Lock(m);
- uDNS_ReceiveNATPMPPacket(m, InterfaceID, pkt, (mDNSu16)(end - (mDNSu8 *)pkt));
- mDNS_Unlock(m);
- return;
- }
- }
+ if (mDNSSameIPPort(srcport, NATPMPPort))
+ {
+ mDNS_Lock(m);
+ uDNS_ReceiveNATPacket(m, InterfaceID, pkt, (mDNSu16)(end - (mDNSu8 *)pkt));
+ mDNS_Unlock(m);
+ return;
+ }
+ }
#ifdef _LEGACY_NAT_TRAVERSAL_
- else if (m->SSDPSocket && mDNSSameIPPort(dstport, m->SSDPSocket->port)) { debugf("Ignoring SSDP response from %#a:%d", srcaddr, mDNSVal16(srcport)); return; }
+ else if (m->SSDPSocket && mDNSSameIPPort(dstport, m->SSDPSocket->port)) { debugf("Ignoring SSDP response from %#a:%d", srcaddr, mDNSVal16(srcport)); return; }
#endif
#endif
- if ((unsigned)(end - (mDNSu8 *)pkt) < sizeof(DNSMessageHeader))
- {
- LogMsg("DNS Message from %#a:%d to %#a:%d length %d too short", srcaddr, mDNSVal16(srcport), dstaddr, mDNSVal16(dstport), end - (mDNSu8 *)pkt);
- return;
- }
- QR_OP = (mDNSu8)(msg->h.flags.b[0] & kDNSFlag0_QROP_Mask);
- // Read the integer parts which are in IETF byte-order (MSB first, LSB second)
- ptr = (mDNSu8 *)&msg->h.numQuestions;
- msg->h.numQuestions = (mDNSu16)((mDNSu16)ptr[0] << 8 | ptr[1]);
- msg->h.numAnswers = (mDNSu16)((mDNSu16)ptr[2] << 8 | ptr[3]);
- msg->h.numAuthorities = (mDNSu16)((mDNSu16)ptr[4] << 8 | ptr[5]);
- msg->h.numAdditionals = (mDNSu16)((mDNSu16)ptr[6] << 8 | ptr[7]);
-
- if (!m) { LogMsg("mDNSCoreReceive ERROR m is NULL"); return; }
-
- // We use zero addresses and all-ones addresses at various places in the code to indicate special values like "no address"
- // If we accept and try to process a packet with zero or all-ones source address, that could really mess things up
- if (srcaddr && !mDNSAddressIsValid(srcaddr)) { debugf("mDNSCoreReceive ignoring packet from %#a", srcaddr); return; }
+ if ((unsigned)(end - (mDNSu8 *)pkt) < sizeof(DNSMessageHeader))
+ {
+ LogMsg("DNS Message from %#a:%d to %#a:%d length %d too short", srcaddr, mDNSVal16(srcport), dstaddr, mDNSVal16(dstport), end - (mDNSu8 *)pkt);
+ return;
+ }
+ QR_OP = (mDNSu8)(msg->h.flags.b[0] & kDNSFlag0_QROP_Mask);
+ // Read the integer parts which are in IETF byte-order (MSB first, LSB second)
+ ptr = (mDNSu8 *)&msg->h.numQuestions;
+ msg->h.numQuestions = (mDNSu16)((mDNSu16)ptr[0] << 8 | ptr[1]);
+ msg->h.numAnswers = (mDNSu16)((mDNSu16)ptr[2] << 8 | ptr[3]);
+ msg->h.numAuthorities = (mDNSu16)((mDNSu16)ptr[4] << 8 | ptr[5]);
+ msg->h.numAdditionals = (mDNSu16)((mDNSu16)ptr[6] << 8 | ptr[7]);
+
+ if (!m) { LogMsg("mDNSCoreReceive ERROR m is NULL"); return; }
+
+ // We use zero addresses and all-ones addresses at various places in the code to indicate special values like "no address"
+ // If we accept and try to process a packet with zero or all-ones source address, that could really mess things up
+ if (srcaddr && !mDNSAddressIsValid(srcaddr)) { debugf("mDNSCoreReceive ignoring packet from %#a", srcaddr); return; }
+
+ mDNS_Lock(m);
+ m->PktNum++;
+ if (mDNSOpaque16IsZero(msg->h.id))
+ {
+ m->MPktNum++;
+#if APPLE_OSX_mDNSResponder
+ // Track the number of multicast packets received from a source outside our subnet.
+ // Check the destination address to avoid accounting for spurious packets that
+ // comes in with message id zero.
+ if (!mDNS_AddressIsLocalSubnet(m, InterfaceID, srcaddr, mDNSNULL) &&
+ mDNSAddressIsAllDNSLinkGroup(dstaddr))
+ {
+ m->RemoteSubnet++;
+ }
+#endif // #if APPLE_OSX_mDNSResponder
+ }
- mDNS_Lock(m);
- m->PktNum++;
#ifndef UNICAST_DISABLED
- if (!dstaddr || (!mDNSAddressIsAllDNSLinkGroup(dstaddr) && (QR_OP == StdR || QR_OP == UpdR)))
- if (!mDNSOpaque16IsZero(msg->h.id)) // uDNS_ReceiveMsg only needs to get real uDNS responses, not "QU" mDNS responses
- {
- ifid = mDNSInterface_Any;
- if (mDNS_PacketLoggingEnabled)
- DumpPacket(m, mStatus_NoError, mDNSfalse, TLS ? "TLS" : !dstaddr ? "TCP" : "UDP", srcaddr, srcport, dstaddr, dstport, msg, end);
- uDNS_ReceiveMsg(m, msg, end, srcaddr, srcport);
- // Note: mDNSCore also needs to get access to received unicast responses
- }
+ if (!dstaddr || (!mDNSAddressIsAllDNSLinkGroup(dstaddr) && (QR_OP == StdR || QR_OP == UpdR)))
+ if (!mDNSOpaque16IsZero(msg->h.id)) // uDNS_ReceiveMsg only needs to get real uDNS responses, not "QU" mDNS responses
+ {
+ ifid = mDNSInterface_Any;
+ if (mDNS_PacketLoggingEnabled)
+ DumpPacket(m, mStatus_NoError, mDNSfalse, TLS ? "TLS" : !dstaddr ? "TCP" : "UDP", srcaddr, srcport, dstaddr, dstport, msg, end);
+ uDNS_ReceiveMsg(m, msg, end, srcaddr, srcport);
+ // Note: mDNSCore also needs to get access to received unicast responses
+ }
#endif
- if (QR_OP == StdQ) mDNSCoreReceiveQuery (m, msg, end, srcaddr, srcport, dstaddr, dstport, ifid);
- else if (QR_OP == StdR) mDNSCoreReceiveResponse(m, msg, end, srcaddr, srcport, dstaddr, dstport, ifid);
- else if (QR_OP == UpdQ) mDNSCoreReceiveUpdate (m, msg, end, srcaddr, srcport, dstaddr, dstport, InterfaceID);
- else if (QR_OP == UpdR) mDNSCoreReceiveUpdateR (m, msg, end, InterfaceID);
- else
- {
- LogMsg("Unknown DNS packet type %02X%02X from %#-15a:%-5d to %#-15a:%-5d length %d on %p (ignored)",
- msg->h.flags.b[0], msg->h.flags.b[1], srcaddr, mDNSVal16(srcport), dstaddr, mDNSVal16(dstport), end - (mDNSu8 *)pkt, InterfaceID);
- if (mDNS_LoggingEnabled)
- {
- int i = 0;
- while (i<end - (mDNSu8 *)pkt)
- {
- char buffer[128];
- char *p = buffer + mDNS_snprintf(buffer, sizeof(buffer), "%04X", i);
- do if (i<end - (mDNSu8 *)pkt) p += mDNS_snprintf(p, sizeof(buffer), " %02X", ((mDNSu8 *)pkt)[i]); while (++i & 15);
- LogInfo("%s", buffer);
- }
- }
- }
- // Packet reception often causes a change to the task list:
- // 1. Inbound queries can cause us to need to send responses
- // 2. Conflicing response packets received from other hosts can cause us to need to send defensive responses
- // 3. Other hosts announcing deletion of shared records can cause us to need to re-assert those records
- // 4. Response packets that answer questions may cause our client to issue new questions
- mDNS_Unlock(m);
- }
+ if (QR_OP == StdQ) mDNSCoreReceiveQuery (m, msg, end, srcaddr, srcport, dstaddr, dstport, ifid);
+ else if (QR_OP == StdR) mDNSCoreReceiveResponse(m, msg, end, srcaddr, srcport, dstaddr, dstport, ifid);
+ else if (QR_OP == UpdQ) mDNSCoreReceiveUpdate (m, msg, end, srcaddr, srcport, dstaddr, dstport, InterfaceID);
+ else if (QR_OP == UpdR) mDNSCoreReceiveUpdateR (m, msg, end, srcaddr, InterfaceID);
+ else
+ {
+ LogMsg("Unknown DNS packet type %02X%02X from %#-15a:%-5d to %#-15a:%-5d length %d on %p (ignored)",
+ msg->h.flags.b[0], msg->h.flags.b[1], srcaddr, mDNSVal16(srcport), dstaddr, mDNSVal16(dstport), end - (mDNSu8 *)pkt, InterfaceID);
+ if (mDNS_LoggingEnabled)
+ {
+ int i = 0;
+ while (i<end - (mDNSu8 *)pkt)
+ {
+ char buffer[128];
+ char *p = buffer + mDNS_snprintf(buffer, sizeof(buffer), "%04X", i);
+ do if (i<end - (mDNSu8 *)pkt) p += mDNS_snprintf(p, sizeof(buffer), " %02X", ((mDNSu8 *)pkt)[i]);while (++i & 15);
+ LogInfo("%s", buffer);
+ }
+ }
+ }
+ // Packet reception often causes a change to the task list:
+ // 1. Inbound queries can cause us to need to send responses
+ // 2. Conflicing response packets received from other hosts can cause us to need to send defensive responses
+ // 3. Other hosts announcing deletion of shared records can cause us to need to re-assert those records
+ // 4. Response packets that answer questions may cause our client to issue new questions
+ mDNS_Unlock(m);
+}
// ***************************************************************************
#if COMPILER_LIKES_PRAGMA_MARK
// if both are targeted to the same address+port
// (If Target address is zero, TargetPort is undefined)
#define SameQTarget(A,B) (((A)->Target.type == mDNSAddrType_None && (B)->Target.type == mDNSAddrType_None) || \
- (mDNSSameAddress(&(A)->Target, &(B)->Target) && mDNSSameIPPort((A)->TargetPort, (B)->TargetPort)))
+ (mDNSSameAddress(& (A)->Target, & (B)->Target) && mDNSSameIPPort((A)->TargetPort, (B)->TargetPort)))
// Note: We explicitly disallow making a public query be a duplicate of a private one. This is to avoid the
// circular deadlock where a client does a query for something like "dns-sd -Q _dns-query-tls._tcp.company.com SRV"
// The main reason for this design is that cache entries point to a *single* question and that question is responsible
// for keeping the cache fresh as long as it is active. Having multiple active question for a single cache entry
// breaks this design principle.
+//
// If IsLLQ(Q) is true, it means the question is both:
// (a) long-lived and
// (b) being performed by a unicast DNS long-lived query (either full LLQ, or polling)
// for multicast questions, we don't want to treat LongLived as anything special
#define IsLLQ(Q) ((Q)->LongLived && !mDNSOpaque16IsZero((Q)->TargetQID))
+#define IsAWDLIncluded(Q) (((Q)->flags & kDNSServiceFlagsIncludeAWDL) != 0)
mDNSlocal DNSQuestion *FindDuplicateQuestion(const mDNS *const m, const DNSQuestion *const question)
- {
- DNSQuestion *q;
- // Note: A question can only be marked as a duplicate of one that occurs *earlier* in the list.
- // This prevents circular references, where two questions are each marked as a duplicate of the other.
- // Accordingly, we break out of the loop when we get to 'question', because there's no point searching
- // further in the list.
- for (q = m->Questions; q && q != question; q=q->next) // Scan our list for another question
- if (q->InterfaceID == question->InterfaceID && // with the same InterfaceID,
- SameQTarget(q, question) && // and same unicast/multicast target settings
- q->qtype == question->qtype && // type,
- q->qclass == question->qclass && // class,
- IsLLQ(q) == IsLLQ(question) && // and long-lived status matches
- (!q->AuthInfo || question->AuthInfo) && // to avoid deadlock, don't make public query dup of a private one
- (q->SuppressQuery == question->SuppressQuery) && // Questions that are suppressed/not suppressed
- q->qnamehash == question->qnamehash &&
- SameDomainName(&q->qname, &question->qname)) // and name
- return(q);
- return(mDNSNULL);
- }
+{
+ DNSQuestion *q;
+ // Note: A question can only be marked as a duplicate of one that occurs *earlier* in the list.
+ // This prevents circular references, where two questions are each marked as a duplicate of the other.
+ // Accordingly, we break out of the loop when we get to 'question', because there's no point searching
+ // further in the list.
+ for (q = m->Questions; q && q != question; q=q->next) // Scan our list for another question
+ if (q->InterfaceID == question->InterfaceID && // with the same InterfaceID,
+ SameQTarget(q, question) && // and same unicast/multicast target settings
+ q->qtype == question->qtype && // type,
+ q->qclass == question->qclass && // class,
+ IsLLQ(q) == IsLLQ(question) && // and long-lived status matches
+ (!q->AuthInfo || question->AuthInfo) && // to avoid deadlock, don't make public query dup of a private one
+ (q->AnonInfo == question->AnonInfo) && // Anonymous query not a dup of normal query
+ (q->SuppressQuery == question->SuppressQuery) && // Questions that are suppressed/not suppressed
+ (q->ValidationRequired == question->ValidationRequired) && // Questions that require DNSSEC validation
+ (q->ValidatingResponse == question->ValidatingResponse) && // Questions that are validating responses using DNSSEC
+ (q->DisallowPID == question->DisallowPID) && // Disallowing a PID should not affect a PID that is allowed
+ (q->BrowseThreshold == question->BrowseThreshold) && // browse thresholds must match
+ q->qnamehash == question->qnamehash &&
+ (IsAWDLIncluded(q) == IsAWDLIncluded(question)) && // Inclusion of AWDL interface must match
+ SameDomainName(&q->qname, &question->qname)) // and name
+ return(q);
+ return(mDNSNULL);
+}
// This is called after a question is deleted, in case other identical questions were being suppressed as duplicates
mDNSlocal void UpdateQuestionDuplicates(mDNS *const m, DNSQuestion *const question)
- {
- DNSQuestion *q;
- DNSQuestion *first = mDNSNULL;
-
- // This is referring to some other question as duplicate. No other question can refer to this
- // question as a duplicate.
- if (question->DuplicateOf)
- {
- LogInfo("UpdateQuestionDuplicates: question %p %##s (%s) duplicate of %p %##s (%s)",
- question, question->qname.c, DNSTypeName(question->qtype),
- question->DuplicateOf, question->DuplicateOf->qname.c, DNSTypeName(question->DuplicateOf->qtype));
- return;
- }
-
- for (q = m->Questions; q; q=q->next) // Scan our list of questions
- if (q->DuplicateOf == question) // To see if any questions were referencing this as their duplicate
- {
- q->DuplicateOf = first;
- if (!first)
- {
- first = q;
- // If q used to be a duplicate, but now is not,
- // then inherit the state from the question that's going away
- q->LastQTime = question->LastQTime;
- q->ThisQInterval = question->ThisQInterval;
- q->ExpectUnicastResp = question->ExpectUnicastResp;
- q->LastAnswerPktNum = question->LastAnswerPktNum;
- q->RecentAnswerPkts = question->RecentAnswerPkts;
- q->RequestUnicast = question->RequestUnicast;
- q->LastQTxTime = question->LastQTxTime;
- q->CNAMEReferrals = question->CNAMEReferrals;
- q->nta = question->nta;
- q->servAddr = question->servAddr;
- q->servPort = question->servPort;
- q->qDNSServer = question->qDNSServer;
- q->validDNSServers = question->validDNSServers;
- q->unansweredQueries = question->unansweredQueries;
- q->noServerResponse = question->noServerResponse;
- q->triedAllServersOnce = question->triedAllServersOnce;
-
- q->TargetQID = question->TargetQID;
- q->LocalSocket = question->LocalSocket;
-
- q->state = question->state;
- // q->tcp = question->tcp;
- q->ReqLease = question->ReqLease;
- q->expire = question->expire;
- q->ntries = question->ntries;
- q->id = question->id;
-
- question->LocalSocket = mDNSNULL;
- question->nta = mDNSNULL; // If we've got a GetZoneData in progress, transfer it to the newly active question
- // question->tcp = mDNSNULL;
-
- if (q->LocalSocket)
- debugf("UpdateQuestionDuplicates transferred LocalSocket pointer for %##s (%s)", q->qname.c, DNSTypeName(q->qtype));
-
- if (q->nta)
- {
- LogInfo("UpdateQuestionDuplicates transferred nta pointer for %##s (%s)", q->qname.c, DNSTypeName(q->qtype));
- q->nta->ZoneDataContext = q;
- }
-
- // Need to work out how to safely transfer this state too -- appropriate context pointers need to be updated or the code will crash
- if (question->tcp) LogInfo("UpdateQuestionDuplicates did not transfer tcp pointer");
-
- if (question->state == LLQ_Established)
- {
- LogInfo("UpdateQuestionDuplicates transferred LLQ state for %##s (%s)", q->qname.c, DNSTypeName(q->qtype));
- question->state = 0; // Must zero question->state, or mDNS_StopQuery_internal will clean up and cancel our LLQ from the server
- }
-
- SetNextQueryTime(m,q);
- }
- }
- }
+{
+ DNSQuestion *q;
+ DNSQuestion *first = mDNSNULL;
+
+ // This is referring to some other question as duplicate. No other question can refer to this
+ // question as a duplicate.
+ if (question->DuplicateOf)
+ {
+ LogInfo("UpdateQuestionDuplicates: question %p %##s (%s) duplicate of %p %##s (%s)",
+ question, question->qname.c, DNSTypeName(question->qtype),
+ question->DuplicateOf, question->DuplicateOf->qname.c, DNSTypeName(question->DuplicateOf->qtype));
+ return;
+ }
+
+ for (q = m->Questions; q; q=q->next) // Scan our list of questions
+ if (q->DuplicateOf == question) // To see if any questions were referencing this as their duplicate
+ {
+ q->DuplicateOf = first;
+ if (!first)
+ {
+ first = q;
+ // If q used to be a duplicate, but now is not,
+ // then inherit the state from the question that's going away
+ q->LastQTime = question->LastQTime;
+ q->ThisQInterval = question->ThisQInterval;
+ q->ExpectUnicastResp = question->ExpectUnicastResp;
+ q->LastAnswerPktNum = question->LastAnswerPktNum;
+ q->RecentAnswerPkts = question->RecentAnswerPkts;
+ q->RequestUnicast = question->RequestUnicast;
+ q->LastQTxTime = question->LastQTxTime;
+ q->CNAMEReferrals = question->CNAMEReferrals;
+ q->nta = question->nta;
+ q->servAddr = question->servAddr;
+ q->servPort = question->servPort;
+ q->qDNSServer = question->qDNSServer;
+ q->validDNSServers = question->validDNSServers;
+ q->unansweredQueries = question->unansweredQueries;
+ q->noServerResponse = question->noServerResponse;
+ q->triedAllServersOnce = question->triedAllServersOnce;
+
+ q->TargetQID = question->TargetQID;
+ if (q->LocalSocket)
+ {
+ mDNSPlatformUDPClose(q->LocalSocket);
+ }
+
+ q->LocalSocket = question->LocalSocket;
+
+ q->state = question->state;
+ // q->tcp = question->tcp;
+ q->ReqLease = question->ReqLease;
+ q->expire = question->expire;
+ q->ntries = question->ntries;
+ q->id = question->id;
+
+ question->LocalSocket = mDNSNULL;
+ question->nta = mDNSNULL; // If we've got a GetZoneData in progress, transfer it to the newly active question
+ // question->tcp = mDNSNULL;
+
+ if (q->LocalSocket)
+ debugf("UpdateQuestionDuplicates transferred LocalSocket pointer for %##s (%s)", q->qname.c, DNSTypeName(q->qtype));
+
+ if (q->nta)
+ {
+ LogInfo("UpdateQuestionDuplicates transferred nta pointer for %##s (%s)", q->qname.c, DNSTypeName(q->qtype));
+ q->nta->ZoneDataContext = q;
+ }
+
+ // Need to work out how to safely transfer this state too -- appropriate context pointers need to be updated or the code will crash
+ if (question->tcp) LogInfo("UpdateQuestionDuplicates did not transfer tcp pointer");
+
+ if (question->state == LLQ_Established)
+ {
+ LogInfo("UpdateQuestionDuplicates transferred LLQ state for %##s (%s)", q->qname.c, DNSTypeName(q->qtype));
+ question->state = 0; // Must zero question->state, or mDNS_StopQuery_internal will clean up and cancel our LLQ from the server
+ }
+
+ SetNextQueryTime(m,q);
+ }
+ }
+}
mDNSexport McastResolver *mDNS_AddMcastResolver(mDNS *const m, const domainname *d, const mDNSInterfaceID interface, mDNSu32 timeout)
- {
- McastResolver **p = &m->McastResolvers;
- McastResolver *tmp = mDNSNULL;
-
- if (!d) d = (const domainname *)"";
-
- LogInfo("mDNS_AddMcastResolver: Adding %##s, InterfaceID %p, timeout %u", d->c, interface, timeout);
-
- if (m->mDNS_busy != m->mDNS_reentrancy+1)
- LogMsg("mDNS_AddMcastResolver: Lock not held! mDNS_busy (%ld) mDNS_reentrancy (%ld)", m->mDNS_busy, m->mDNS_reentrancy);
-
- while (*p) // Check if we already have this {interface, domain} tuple registered
- {
- if ((*p)->interface == interface && SameDomainName(&(*p)->domain, d))
- {
- if (!((*p)->flags & DNSServer_FlagDelete)) LogMsg("Note: Mcast Resolver domain %##s (%p) registered more than once", d->c, interface);
- (*p)->flags &= ~DNSServer_FlagDelete;
- tmp = *p;
- *p = tmp->next;
- tmp->next = mDNSNULL;
- }
- else
- p=&(*p)->next;
- }
-
- if (tmp) *p = tmp; // move to end of list, to ensure ordering from platform layer
- else
- {
- // allocate, add to list
- *p = mDNSPlatformMemAllocate(sizeof(**p));
- if (!*p) LogMsg("mDNS_AddMcastResolver: ERROR!! - malloc");
- else
- {
- (*p)->interface = interface;
- (*p)->flags = DNSServer_FlagNew;
- (*p)->timeout = timeout;
- AssignDomainName(&(*p)->domain, d);
- (*p)->next = mDNSNULL;
- }
- }
- return(*p);
- }
+{
+ McastResolver **p = &m->McastResolvers;
+ McastResolver *tmp = mDNSNULL;
+
+ if (!d) d = (const domainname *)"";
+
+ LogInfo("mDNS_AddMcastResolver: Adding %##s, InterfaceID %p, timeout %u", d->c, interface, timeout);
+
+ mDNS_CheckLock(m);
+
+ while (*p) // Check if we already have this {interface, domain} tuple registered
+ {
+ if ((*p)->interface == interface && SameDomainName(&(*p)->domain, d))
+ {
+ if (!((*p)->flags & DNSServer_FlagDelete)) LogMsg("Note: Mcast Resolver domain %##s (%p) registered more than once", d->c, interface);
+ (*p)->flags &= ~DNSServer_FlagDelete;
+ tmp = *p;
+ *p = tmp->next;
+ tmp->next = mDNSNULL;
+ }
+ else
+ p=&(*p)->next;
+ }
+
+ if (tmp) *p = tmp; // move to end of list, to ensure ordering from platform layer
+ else
+ {
+ // allocate, add to list
+ *p = mDNSPlatformMemAllocate(sizeof(**p));
+ if (!*p) LogMsg("mDNS_AddMcastResolver: ERROR!! - malloc");
+ else
+ {
+ (*p)->interface = interface;
+ (*p)->flags = DNSServer_FlagNew;
+ (*p)->timeout = timeout;
+ AssignDomainName(&(*p)->domain, d);
+ (*p)->next = mDNSNULL;
+ }
+ }
+ return(*p);
+}
mDNSinline mDNSs32 PenaltyTimeForServer(mDNS *m, DNSServer *server)
- {
- mDNSs32 ptime = 0;
- if (server->penaltyTime != 0)
- {
- ptime = server->penaltyTime - m->timenow;
- if (ptime < 0)
- {
- // This should always be a positive value between 0 and DNSSERVER_PENALTY_TIME
- // If it does not get reset in ResetDNSServerPenalties for some reason, we do it
- // here
- LogMsg("PenaltyTimeForServer: PenaltyTime negative %d, (server penaltyTime %d, timenow %d) resetting the penalty",
- ptime, server->penaltyTime, m->timenow);
- server->penaltyTime = 0;
- ptime = 0;
- }
- }
- return ptime;
- }
+{
+ mDNSs32 ptime = 0;
+ if (server->penaltyTime != 0)
+ {
+ ptime = server->penaltyTime - m->timenow;
+ if (ptime < 0)
+ {
+ // This should always be a positive value between 0 and DNSSERVER_PENALTY_TIME
+ // If it does not get reset in ResetDNSServerPenalties for some reason, we do it
+ // here
+ LogMsg("PenaltyTimeForServer: PenaltyTime negative %d, (server penaltyTime %d, timenow %d) resetting the penalty",
+ ptime, server->penaltyTime, m->timenow);
+ server->penaltyTime = 0;
+ ptime = 0;
+ }
+ }
+ return ptime;
+}
//Checks to see whether the newname is a better match for the name, given the best one we have
//seen so far (given in bestcount).
//Returns 0 if the newname is the same as the old match
//Returns 1 if the newname is a better match
mDNSlocal int BetterMatchForName(const domainname *name, int namecount, const domainname *newname, int newcount,
- int bestcount)
- {
- // If the name contains fewer labels than the new server's domain or the new name
- // contains fewer labels than the current best, then it can't possibly be a better match
- if (namecount < newcount || newcount < bestcount) return -1;
-
- // If there is no match, return -1 and the caller will skip this newname for
- // selection
- //
- // If we find a match and the number of labels is the same as bestcount, then
- // we return 0 so that the caller can do additional logic to pick one of
- // the best based on some other factors e.g., penaltyTime
- //
- // If we find a match and the number of labels is more than bestcount, then we
- // return 1 so that the caller can pick this over the old one.
- //
- // Note: newcount can either be equal or greater than bestcount beause of the
- // check above.
-
- if (SameDomainName(SkipLeadingLabels(name, namecount - newcount), newname))
- return bestcount == newcount ? 0 : 1;
- else
- return -1;
- }
+ int bestcount)
+{
+ // If the name contains fewer labels than the new server's domain or the new name
+ // contains fewer labels than the current best, then it can't possibly be a better match
+ if (namecount < newcount || newcount < bestcount) return -1;
+
+ // If there is no match, return -1 and the caller will skip this newname for
+ // selection
+ //
+ // If we find a match and the number of labels is the same as bestcount, then
+ // we return 0 so that the caller can do additional logic to pick one of
+ // the best based on some other factors e.g., penaltyTime
+ //
+ // If we find a match and the number of labels is more than bestcount, then we
+ // return 1 so that the caller can pick this over the old one.
+ //
+ // Note: newcount can either be equal or greater than bestcount beause of the
+ // check above.
+
+ if (SameDomainName(SkipLeadingLabels(name, namecount - newcount), newname))
+ return bestcount == newcount ? 0 : 1;
+ else
+ return -1;
+}
// Normally, we have McastResolvers for .local, in-addr.arpa and ip6.arpa. But there
// can be queries that can forced to multicast (ForceMCast) even though they don't end in these
// names. In that case, we give a default timeout of 5 seconds
-#define DEFAULT_MCAST_TIMEOUT 5
+#define DEFAULT_MCAST_TIMEOUT 5
mDNSlocal mDNSu32 GetTimeoutForMcastQuestion(mDNS *m, DNSQuestion *question)
- {
- McastResolver *curmatch = mDNSNULL;
- int bestmatchlen = -1, namecount = CountLabels(&question->qname);
- McastResolver *curr;
- int bettermatch, currcount;
- for (curr = m->McastResolvers; curr; curr = curr->next)
- {
- currcount = CountLabels(&curr->domain);
- bettermatch = BetterMatchForName(&question->qname, namecount, &curr->domain, currcount, bestmatchlen);
- // Take the first best match. If there are multiple equally good matches (bettermatch = 0), we take
- // the timeout value from the first one
- if (bettermatch == 1)
- {
- curmatch = curr;
- bestmatchlen = currcount;
- }
- }
- LogInfo("GetTimeoutForMcastQuestion: question %##s curmatch %p, Timeout %d", question->qname.c, curmatch,
- curmatch ? curmatch->timeout : DEFAULT_MCAST_TIMEOUT);
- return ( curmatch ? curmatch->timeout : DEFAULT_MCAST_TIMEOUT);
- }
+{
+ McastResolver *curmatch = mDNSNULL;
+ int bestmatchlen = -1, namecount = CountLabels(&question->qname);
+ McastResolver *curr;
+ int bettermatch, currcount;
+ for (curr = m->McastResolvers; curr; curr = curr->next)
+ {
+ currcount = CountLabels(&curr->domain);
+ bettermatch = BetterMatchForName(&question->qname, namecount, &curr->domain, currcount, bestmatchlen);
+ // Take the first best match. If there are multiple equally good matches (bettermatch = 0), we take
+ // the timeout value from the first one
+ if (bettermatch == 1)
+ {
+ curmatch = curr;
+ bestmatchlen = currcount;
+ }
+ }
+ LogInfo("GetTimeoutForMcastQuestion: question %##s curmatch %p, Timeout %d", question->qname.c, curmatch,
+ curmatch ? curmatch->timeout : DEFAULT_MCAST_TIMEOUT);
+ return ( curmatch ? curmatch->timeout : DEFAULT_MCAST_TIMEOUT);
+}
+
+// Returns true if it is a Domain Enumeration Query
+mDNSexport mDNSBool DomainEnumQuery(const domainname *qname)
+{
+ const mDNSu8 *mDNS_DEQLabels[] = { (const mDNSu8 *)"\001b", (const mDNSu8 *)"\002db", (const mDNSu8 *)"\002lb",
+ (const mDNSu8 *)"\001r", (const mDNSu8 *)"\002dr", (const mDNSu8 *)mDNSNULL, };
+ const domainname *d = qname;
+ const mDNSu8 *label;
+ int i = 0;
+
+ // We need at least 3 labels (DEQ prefix) + one more label to make a meaningful DE query
+ if (CountLabels(qname) < 4) { debugf("DomainEnumQuery: question %##s, not enough labels", qname->c); return mDNSfalse; }
+
+ label = (const mDNSu8 *)d;
+ while (mDNS_DEQLabels[i] != (const mDNSu8 *)mDNSNULL)
+ {
+ if (SameDomainLabel(mDNS_DEQLabels[i], label)) {debugf("DomainEnumQuery: DEQ %##s, label1 match", qname->c); break;}
+ i++;
+ }
+ if (mDNS_DEQLabels[i] == (const mDNSu8 *)mDNSNULL)
+ {
+ debugf("DomainEnumQuery: Not a DEQ %##s, label1 mismatch", qname->c);
+ return mDNSfalse;
+ }
+ debugf("DomainEnumQuery: DEQ %##s, label1 match", qname->c);
+
+ // CountLabels already verified the number of labels
+ d = (const domainname *)(d->c + 1 + d->c[0]); // Second Label
+ label = (const mDNSu8 *)d;
+ if (!SameDomainLabel(label, (const mDNSu8 *)"\007_dns-sd"))
+ {
+ debugf("DomainEnumQuery: Not a DEQ %##s, label2 mismatch", qname->c);
+ return(mDNSfalse);
+ }
+ debugf("DomainEnumQuery: DEQ %##s, label2 match", qname->c);
+
+ d = (const domainname *)(d->c + 1 + d->c[0]); // Third Label
+ label = (const mDNSu8 *)d;
+ if (!SameDomainLabel(label, (const mDNSu8 *)"\004_udp"))
+ {
+ debugf("DomainEnumQuery: Not a DEQ %##s, label3 mismatch", qname->c);
+ return(mDNSfalse);
+ }
+ debugf("DomainEnumQuery: DEQ %##s, label3 match", qname->c);
+
+ debugf("DomainEnumQuery: Question %##s is a Domain Enumeration query", qname->c);
+
+ return mDNStrue;
+}
+
+// Note: InterfaceID is the InterfaceID of the question
+mDNSlocal mDNSBool DNSServerMatch(DNSServer *d, mDNSInterfaceID InterfaceID, mDNSs32 ServiceID)
+{
+ // 1) Unscoped questions (NULL InterfaceID) should consider *only* unscoped DNSServers ( DNSServer
+ // with "scoped" set to kScopeNone)
+ //
+ // 2) Scoped questions (non-NULL InterfaceID) should consider *only* scoped DNSServers (DNSServer
+ // with "scoped" set to kScopeInterfaceId) and their InterfaceIDs should match.
+ //
+ // 3) Scoped questions (non-zero ServiceID) should consider *only* scoped DNSServers (DNSServer
+ // with "scoped" set to kScopeServiceID) and their ServiceIDs should match.
+ //
+ // The first condition in the "if" statement checks to see if both the question and the DNSServer are
+ // unscoped. The question is unscoped only if InterfaceID is zero and ServiceID is -1.
+ //
+ // If the first condition fails, following are the possible cases (the notes below are using
+ // InterfaceID for discussion and the same holds good for ServiceID):
+ //
+ // - DNSServer is not scoped, InterfaceID is not NULL - we should skip the current DNSServer entry
+ // as scoped questions should not pick non-scoped DNSServer entry (Refer to (2) above).
+ //
+ // - DNSServer is scoped, InterfaceID is NULL - we should skip the current DNSServer entry as
+ // unscoped question should not match scoped DNSServer (Refer to (1) above). The InterfaceID check
+ // would fail in this case.
+ //
+ // - DNSServer is scoped and InterfaceID is not NULL - the InterfaceID of the question and the DNSServer
+ // should match (Refer to (2) above).
+ //
+ // Note: mDNSInterface_Unicast is used only by .local unicast questions and are treated as unscoped.
+ // If a question is scoped both to InterfaceID and ServiceID, the question will be scoped to InterfaceID.
+
+ if (((d->scoped == kScopeNone) && ((!InterfaceID && ServiceID == -1) || InterfaceID == mDNSInterface_Unicast)) ||
+ ((d->scoped == kScopeInterfaceID) && d->interface == InterfaceID) ||
+ ((d->scoped == kScopeServiceID) && d->serviceID == ServiceID))
+ {
+ return mDNStrue;
+ }
+ return mDNSfalse;
+}
// Sets all the Valid DNS servers for a question
mDNSexport mDNSu32 SetValidDNSServers(mDNS *m, DNSQuestion *question)
- {
- DNSServer *curmatch = mDNSNULL;
- int bestmatchlen = -1, namecount = CountLabels(&question->qname);
- DNSServer *curr;
- int bettermatch, currcount;
- int index = 0;
- mDNSu32 timeout = 0;
-
- question->validDNSServers = zeroOpaque64;
- for (curr = m->DNSServers; curr; curr = curr->next)
- {
- debugf("SetValidDNSServers: Parsing DNS server Address %#a (Domain %##s), Scope: %d", &curr->addr, curr->domain.c, curr->scoped);
- // skip servers that will soon be deleted
- if (curr->flags & DNSServer_FlagDelete)
- { debugf("SetValidDNSServers: Delete set for index %d, DNS server %#a (Domain %##s), scoped %d", index, &curr->addr, curr->domain.c, curr->scoped); continue; }
-
- // This happens normally when you unplug the interface where we reset the interfaceID to mDNSInterface_Any for all
- // the DNS servers whose scope match the interfaceID. Few seconds later, we also receive the updated DNS configuration.
- // But any questions that has mDNSInterface_Any scope that are started/restarted before we receive the update
- // (e.g., CheckSuppressUnusableQuestions is called when interfaces are deregistered with the core) should not
- // match the scoped entries by mistake.
- //
- // Note: DNS configuration change will help pick the new dns servers but currently it does not affect the timeout
-
- if (curr->scoped && curr->interface == mDNSInterface_Any)
- { debugf("SetValidDNSServers: Scoped DNS server %#a (Domain %##s) with Interface Any", &curr->addr, curr->domain.c); continue; }
-
- currcount = CountLabels(&curr->domain);
- if ((!curr->scoped && (!question->InterfaceID || (question->InterfaceID == mDNSInterface_Unicast))) || (curr->interface == question->InterfaceID))
- {
- bettermatch = BetterMatchForName(&question->qname, namecount, &curr->domain, currcount, bestmatchlen);
-
- // If we found a better match (bettermatch == 1) then clear all the bits
- // corresponding to the old DNSServers that we have may set before and start fresh.
- // If we find an equal match, then include that DNSServer also by setting the corresponding
- // bit
- if ((bettermatch == 1) || (bettermatch == 0))
- {
- curmatch = curr;
- bestmatchlen = currcount;
- if (bettermatch) { debugf("SetValidDNSServers: Resetting all the bits"); question->validDNSServers = zeroOpaque64; timeout = 0; }
- debugf("SetValidDNSServers: question %##s Setting the bit for DNS server Address %#a (Domain %##s), Scoped:%d index %d,"
- " Timeout %d, interface %p", question->qname.c, &curr->addr, curr->domain.c, curr->scoped, index, curr->timeout,
- curr->interface);
- timeout += curr->timeout;
- bit_set_opaque64(question->validDNSServers, index);
- }
- }
- index++;
- }
- question->noServerResponse = 0;
-
- debugf("SetValidDNSServers: ValidDNSServer bits 0x%x%x for question %p %##s (%s)",
- question->validDNSServers.l[1], question->validDNSServers.l[0], question, question->qname.c, DNSTypeName(question->qtype));
- // If there are no matching resolvers, then use the default value to timeout
- return (timeout ? timeout : DEFAULT_UDNS_TIMEOUT);
- }
+{
+ int bestmatchlen = -1, namecount = CountLabels(&question->qname);
+ DNSServer *curr;
+ int bettermatch, currcount;
+ int index = 0;
+ mDNSu32 timeout = 0;
+ mDNSBool DEQuery;
+
+ question->validDNSServers = zeroOpaque64;
+ DEQuery = DomainEnumQuery(&question->qname);
+ for (curr = m->DNSServers; curr; curr = curr->next)
+ {
+ debugf("SetValidDNSServers: Parsing DNS server Address %#a (Domain %##s), Scope: %d", &curr->addr, curr->domain.c, curr->scoped);
+ // skip servers that will soon be deleted
+ if (curr->flags & DNSServer_FlagDelete)
+ {
+ debugf("SetValidDNSServers: Delete set for index %d, DNS server %#a (Domain %##s), scoped %d", index, &curr->addr, curr->domain.c, curr->scoped);
+ continue;
+ }
+
+ // This happens normally when you unplug the interface where we reset the interfaceID to mDNSInterface_Any for all
+ // the DNS servers whose scope match the interfaceID. Few seconds later, we also receive the updated DNS configuration.
+ // But any questions that has mDNSInterface_Any scope that are started/restarted before we receive the update
+ // (e.g., CheckSuppressUnusableQuestions is called when interfaces are deregistered with the core) should not
+ // match the scoped entries by mistake.
+ //
+ // Note: DNS configuration change will help pick the new dns servers but currently it does not affect the timeout
+
+ if (curr->scoped && curr->interface == mDNSInterface_Any)
+ {
+ debugf("SetValidDNSServers: Scoped DNS server %#a (Domain %##s) with Interface Any", &curr->addr, curr->domain.c);
+ continue;
+ }
+
+ currcount = CountLabels(&curr->domain);
+ if ((!DEQuery || !curr->cellIntf) && DNSServerMatch(curr, question->InterfaceID, question->ServiceID))
+ {
+ bettermatch = BetterMatchForName(&question->qname, namecount, &curr->domain, currcount, bestmatchlen);
+
+ // If we found a better match (bettermatch == 1) then clear all the bits
+ // corresponding to the old DNSServers that we have may set before and start fresh.
+ // If we find an equal match, then include that DNSServer also by setting the corresponding
+ // bit
+ if ((bettermatch == 1) || (bettermatch == 0))
+ {
+ bestmatchlen = currcount;
+ if (bettermatch)
+ {
+ debugf("SetValidDNSServers: Resetting all the bits");
+ question->validDNSServers = zeroOpaque64;
+ timeout = 0;
+ }
+ debugf("SetValidDNSServers: question %##s Setting the bit for DNS server Address %#a (Domain %##s), Scoped:%d index %d,"
+ " Timeout %d, interface %p", question->qname.c, &curr->addr, curr->domain.c, curr->scoped, index, curr->timeout,
+ curr->interface);
+ timeout += curr->timeout;
+ if (DEQuery)
+ debugf("DomainEnumQuery: Question %##s, DNSServer %#a, cell %d", question->qname.c, &curr->addr, curr->cellIntf);
+ bit_set_opaque64(question->validDNSServers, index);
+ }
+ }
+ index++;
+ }
+ question->noServerResponse = 0;
+
+ debugf("SetValidDNSServers: ValidDNSServer bits 0x%x%x for question %p %##s (%s)",
+ question->validDNSServers.l[1], question->validDNSServers.l[0], question, question->qname.c, DNSTypeName(question->qtype));
+ // If there are no matching resolvers, then use the default timeout value.
+ // For ProxyQuestion, shorten the timeout so that dig does not timeout on us in case of no response.
+ return ((question->ProxyQuestion || question->ValidatingResponse) ? DEFAULT_UDNSSEC_TIMEOUT : timeout ? timeout : DEFAULT_UDNS_TIMEOUT);
+}
// Get the Best server that matches a name. If you find penalized servers, look for the one
// that will come out of the penalty box soon
-mDNSlocal DNSServer *GetBestServer(mDNS *m, const domainname *name, mDNSInterfaceID InterfaceID, mDNSOpaque64 validBits, int *selected, mDNSBool nameMatch)
- {
- DNSServer *curmatch = mDNSNULL;
- int bestmatchlen = -1, namecount = name ? CountLabels(name) : 0;
- DNSServer *curr;
- mDNSs32 bestPenaltyTime, currPenaltyTime;
- int bettermatch, currcount;
- int index = 0;
- int currindex = -1;
-
- debugf("GetBestServer: ValidDNSServer bits 0x%x%x", validBits.l[1], validBits.l[0]);
- bestPenaltyTime = DNSSERVER_PENALTY_TIME + 1;
- for (curr = m->DNSServers; curr; curr = curr->next)
- {
- // skip servers that will soon be deleted
- if (curr->flags & DNSServer_FlagDelete)
- { debugf("GetBestServer: Delete set for index %d, DNS server %#a (Domain %##s), scoped %d", index, &curr->addr, curr->domain.c, curr->scoped); continue; }
-
- // Check if this is a valid DNSServer
- if (!bit_get_opaque64(validBits, index)) { debugf("GetBestServer: continuing for index %d", index); index++; continue; }
-
- currcount = CountLabels(&curr->domain);
- currPenaltyTime = PenaltyTimeForServer(m, curr);
-
- debugf("GetBestServer: Address %#a (Domain %##s), PenaltyTime(abs) %d, PenaltyTime(rel) %d",
- &curr->addr, curr->domain.c, curr->penaltyTime, currPenaltyTime);
-
- // If there are multiple best servers for a given question, we will pick the first one
- // if none of them are penalized. If some of them are penalized in that list, we pick
- // the least penalized one. BetterMatchForName walks through all best matches and
- // "currPenaltyTime < bestPenaltyTime" check lets us either pick the first best server
- // in the list when there are no penalized servers and least one among them
- // when there are some penalized servers
- //
- // Notes on InterfaceID matching:
- //
- // 1) A DNSServer entry may have an InterfaceID but the scoped flag may not be set. This
- // is the old way of specifying an InterfaceID option for DNSServer. We recoginize these
- // entries by "scoped" being false. These are like any other unscoped entries except that
- // if it is picked e.g., domain match, when the packet is sent out later, the packet will
- // be sent out on that interface. Theese entries can be matched by either specifying a
- // zero InterfaceID or non-zero InterfaceID on the question. Specifying an InterfaceID on
- // the question will cause an extra check on matching the InterfaceID on the question
- // against the DNSServer.
- //
- // 2) A DNSServer may also have both scoped set and InterfaceID non-NULL. This
- // is the new way of specifying an InterfaceID option for DNSServer. These will be considered
- // only when the question has non-zero interfaceID.
-
- if ((!curr->scoped && !InterfaceID) || (curr->interface == InterfaceID))
- {
-
- // If we know that all the names are already equally good matches, then skip calling BetterMatchForName.
- // This happens when we initially walk all the DNS servers and set the validity bit on the question.
- // Actually we just need PenaltyTime match, but for the sake of readability we just skip the expensive
- // part and still do some redundant steps e.g., InterfaceID match
-
- if (nameMatch) bettermatch = BetterMatchForName(name, namecount, &curr->domain, currcount, bestmatchlen);
- else bettermatch = 0;
-
- // If we found a better match (bettermatch == 1) then we don't need to
- // compare penalty times. But if we found an equal match, then we compare
- // the penalty times to pick a better match
-
- if ((bettermatch == 1) || ((bettermatch == 0) && currPenaltyTime < bestPenaltyTime))
- { currindex = index; curmatch = curr; bestmatchlen = currcount; bestPenaltyTime = currPenaltyTime; }
- }
- index++;
- }
- if (selected) *selected = currindex;
- return curmatch;
- }
+mDNSlocal DNSServer *GetBestServer(mDNS *m, const domainname *name, mDNSInterfaceID InterfaceID, mDNSs32 ServiceID, mDNSOpaque64 validBits,
+ int *selected, mDNSBool nameMatch)
+{
+ DNSServer *curmatch = mDNSNULL;
+ int bestmatchlen = -1, namecount = name ? CountLabels(name) : 0;
+ DNSServer *curr;
+ mDNSs32 bestPenaltyTime, currPenaltyTime;
+ int bettermatch, currcount;
+ int index = 0;
+ int currindex = -1;
+
+ debugf("GetBestServer: ValidDNSServer bits 0x%x%x", validBits.l[1], validBits.l[0]);
+ bestPenaltyTime = DNSSERVER_PENALTY_TIME + 1;
+ for (curr = m->DNSServers; curr; curr = curr->next)
+ {
+ // skip servers that will soon be deleted
+ if (curr->flags & DNSServer_FlagDelete)
+ {
+ debugf("GetBestServer: Delete set for index %d, DNS server %#a (Domain %##s), scoped %d", index, &curr->addr, curr->domain.c, curr->scoped);
+ continue;
+ }
+
+ // Check if this is a valid DNSServer
+ if (!bit_get_opaque64(validBits, index))
+ {
+ debugf("GetBestServer: continuing for index %d", index);
+ index++;
+ continue;
+ }
+
+ currcount = CountLabels(&curr->domain);
+ currPenaltyTime = PenaltyTimeForServer(m, curr);
+
+ debugf("GetBestServer: Address %#a (Domain %##s), PenaltyTime(abs) %d, PenaltyTime(rel) %d",
+ &curr->addr, curr->domain.c, curr->penaltyTime, currPenaltyTime);
+
+ // If there are multiple best servers for a given question, we will pick the first one
+ // if none of them are penalized. If some of them are penalized in that list, we pick
+ // the least penalized one. BetterMatchForName walks through all best matches and
+ // "currPenaltyTime < bestPenaltyTime" check lets us either pick the first best server
+ // in the list when there are no penalized servers and least one among them
+ // when there are some penalized servers.
+
+ if (DNSServerMatch(curr, InterfaceID, ServiceID))
+ {
+
+ // If we know that all the names are already equally good matches, then skip calling BetterMatchForName.
+ // This happens when we initially walk all the DNS servers and set the validity bit on the question.
+ // Actually we just need PenaltyTime match, but for the sake of readability we just skip the expensive
+ // part and still do some redundant steps e.g., InterfaceID match
+
+ if (nameMatch)
+ bettermatch = BetterMatchForName(name, namecount, &curr->domain, currcount, bestmatchlen);
+ else
+ bettermatch = 0;
+
+ // If we found a better match (bettermatch == 1) then we don't need to
+ // compare penalty times. But if we found an equal match, then we compare
+ // the penalty times to pick a better match
+
+ if ((bettermatch == 1) || ((bettermatch == 0) && currPenaltyTime < bestPenaltyTime))
+ {
+ currindex = index;
+ curmatch = curr;
+ bestmatchlen = currcount;
+ bestPenaltyTime = currPenaltyTime;
+ }
+ }
+ index++;
+ }
+ if (selected) *selected = currindex;
+ return curmatch;
+}
// Look up a DNS Server, matching by name and InterfaceID
-mDNSexport DNSServer *GetServerForName(mDNS *m, const domainname *name, mDNSInterfaceID InterfaceID)
- {
- DNSServer *curmatch = mDNSNULL;
- char *ifname = mDNSNULL; // for logging purposes only
- mDNSOpaque64 allValid;
+mDNSlocal DNSServer *GetServerForName(mDNS *m, const domainname *name, mDNSInterfaceID InterfaceID, mDNSs32 ServiceID)
+{
+ DNSServer *curmatch = mDNSNULL;
+ char *ifname = mDNSNULL; // for logging purposes only
+ mDNSOpaque64 allValid;
- if ((InterfaceID == mDNSInterface_Unicast) || (InterfaceID == mDNSInterface_LocalOnly))
- InterfaceID = mDNSNULL;
+ if ((InterfaceID == mDNSInterface_Unicast) || (InterfaceID == mDNSInterface_LocalOnly))
+ InterfaceID = mDNSNULL;
- if (InterfaceID) ifname = InterfaceNameForID(m, InterfaceID);
+ if (InterfaceID) ifname = InterfaceNameForID(m, InterfaceID);
- // By passing in all ones, we make sure that every DNS server is considered
- allValid.l[0] = allValid.l[1] = 0xFFFFFFFF;
+ // By passing in all ones, we make sure that every DNS server is considered
+ allValid.l[0] = allValid.l[1] = 0xFFFFFFFF;
- curmatch = GetBestServer(m, name, InterfaceID, allValid, mDNSNULL, mDNStrue);
+ curmatch = GetBestServer(m, name, InterfaceID, ServiceID, allValid, mDNSNULL, mDNStrue);
- if (curmatch != mDNSNULL)
- LogInfo("GetServerForName: DNS server %#a:%d (Penalty Time Left %d) (Scope %s:%p) found for name %##s", &curmatch->addr,
- mDNSVal16(curmatch->port), (curmatch->penaltyTime ? (curmatch->penaltyTime - m->timenow) : 0), ifname ? ifname : "None",
- InterfaceID, name);
- else
- LogInfo("GetServerForName: no DNS server (Scope %s:%p) found for name %##s", ifname ? ifname : "None", InterfaceID, name);
+ if (curmatch != mDNSNULL)
+ LogInfo("GetServerForName: DNS server %#a:%d (Penalty Time Left %d) (Scope %s:%p) found for name %##s", &curmatch->addr,
+ mDNSVal16(curmatch->port), (curmatch->penaltyTime ? (curmatch->penaltyTime - m->timenow) : 0), ifname ? ifname : "None",
+ InterfaceID, name);
+ else
+ LogInfo("GetServerForName: no DNS server (Scope %s:%p) found for name %##s", ifname ? ifname : "None", InterfaceID, name);
- return(curmatch);
- }
+ return(curmatch);
+}
// Look up a DNS Server for a question within its valid DNSServer bits
mDNSexport DNSServer *GetServerForQuestion(mDNS *m, DNSQuestion *question)
- {
- DNSServer *curmatch = mDNSNULL;
- char *ifname = mDNSNULL; // for logging purposes only
- mDNSInterfaceID InterfaceID = question->InterfaceID;
- const domainname *name = &question->qname;
- int currindex;
+{
+ DNSServer *curmatch = mDNSNULL;
+ char *ifname = mDNSNULL; // for logging purposes only
+ mDNSInterfaceID InterfaceID = question->InterfaceID;
+ const domainname *name = &question->qname;
+ int currindex;
- if ((InterfaceID == mDNSInterface_Unicast) || (InterfaceID == mDNSInterface_LocalOnly))
- InterfaceID = mDNSNULL;
+ if ((InterfaceID == mDNSInterface_Unicast) || (InterfaceID == mDNSInterface_LocalOnly))
+ InterfaceID = mDNSNULL;
- if (InterfaceID) ifname = InterfaceNameForID(m, InterfaceID);
+ if (InterfaceID)
+ ifname = InterfaceNameForID(m, InterfaceID);
- if (!mDNSOpaque64IsZero(&question->validDNSServers))
- {
- curmatch = GetBestServer(m, name, InterfaceID, question->validDNSServers, &currindex, mDNSfalse);
- if (currindex != -1) bit_clr_opaque64(question->validDNSServers, currindex);
- }
+ if (!mDNSOpaque64IsZero(&question->validDNSServers))
+ {
+ curmatch = GetBestServer(m, name, InterfaceID, question->ServiceID, question->validDNSServers, &currindex, mDNSfalse);
+ if (currindex != -1)
+ bit_clr_opaque64(question->validDNSServers, currindex);
+ }
- if (curmatch != mDNSNULL)
- LogInfo("GetServerForQuestion: %p DNS server %#a:%d (Penalty Time Left %d) (Scope %s:%p) found for name %##s (%s)", question, &curmatch->addr,
- mDNSVal16(curmatch->port), (curmatch->penaltyTime ? (curmatch->penaltyTime - m->timenow) : 0), ifname ? ifname : "None",
- InterfaceID, name, DNSTypeName(question->qtype));
- else
- LogInfo("GetServerForQuestion: %p no DNS server (Scope %s:%p) found for name %##s (%s)", question, ifname ? ifname : "None", InterfaceID, name, DNSTypeName(question->qtype));
+ if (curmatch != mDNSNULL)
+ {
+ LogInfo("GetServerForQuestion: %p DNS server (%p) %#a:%d (Penalty Time Left %d) (Scope %s:%p:%d) found for name %##s (%s)",
+ question, curmatch, &curmatch->addr, mDNSVal16(curmatch->port),
+ (curmatch->penaltyTime ? (curmatch->penaltyTime - m->timenow) : 0), ifname ? ifname : "None",
+ InterfaceID, question->ServiceID, name, DNSTypeName(question->qtype));
+ }
+ else
+ {
+ LogInfo("GetServerForQuestion: %p no DNS server (Scope %s:%p:%d) found for name %##s (%s)",
+ question, ifname ? ifname : "None", InterfaceID, question->ServiceID, name, DNSTypeName(question->qtype));
+ }
- return(curmatch);
- }
+ return(curmatch);
+}
#define ValidQuestionTarget(Q) (((Q)->Target.type == mDNSAddrType_IPv4 || (Q)->Target.type == mDNSAddrType_IPv6) && \
- (mDNSSameIPPort((Q)->TargetPort, UnicastDNSPort) || mDNSSameIPPort((Q)->TargetPort, MulticastDNSPort)))
+ (mDNSSameIPPort((Q)->TargetPort, UnicastDNSPort) || mDNSSameIPPort((Q)->TargetPort, MulticastDNSPort)))
// Called in normal client context (lock not held)
mDNSlocal void LLQNATCallback(mDNS *m, NATTraversalInfo *n)
- {
- DNSQuestion *q;
- (void)n; // Unused
- mDNS_Lock(m);
- LogInfo("LLQNATCallback external address:port %.4a:%u, NAT result %d", &n->ExternalAddress, mDNSVal16(n->ExternalPort), n->Result);
- for (q = m->Questions; q; q=q->next)
- if (ActiveQuestion(q) && !mDNSOpaque16IsZero(q->TargetQID) && q->LongLived)
- startLLQHandshake(m, q); // If ExternalPort is zero, will do StartLLQPolling instead
+{
+ DNSQuestion *q;
+ mDNS_Lock(m);
+ LogInfo("LLQNATCallback external address:port %.4a:%u, NAT result %d", &n->ExternalAddress, mDNSVal16(n->ExternalPort), n->Result);
+ n->clientContext = mDNSNULL; // we received at least one callback since starting this NAT-T
+ for (q = m->Questions; q; q=q->next)
+ if (ActiveQuestion(q) && !mDNSOpaque16IsZero(q->TargetQID) && q->LongLived)
+ startLLQHandshake(m, q); // If ExternalPort is zero, will do StartLLQPolling instead
#if APPLE_OSX_mDNSResponder
- UpdateAutoTunnelDomainStatuses(m);
+ UpdateAutoTunnelDomainStatuses(m);
#endif
- mDNS_Unlock(m);
- }
-
-mDNSlocal mDNSBool ShouldSuppressQuery(mDNS *const m, domainname *qname, mDNSu16 qtype, mDNSInterfaceID InterfaceID)
- {
- NetworkInterfaceInfo *i;
- mDNSs32 iptype;
- DomainAuthInfo *AuthInfo;
-
- if (qtype == kDNSType_A) iptype = mDNSAddrType_IPv4;
- else if (qtype == kDNSType_AAAA) iptype = mDNSAddrType_IPv6;
- else { LogInfo("ShouldSuppressQuery: Query not suppressed for %##s, qtype %s, not A/AAAA type", qname, DNSTypeName(qtype)); return mDNSfalse; }
-
- // We still want the ability to be able to listen to the local services and hence
- // don't fail .local requests. We always have a loopback interface which we don't
- // check here.
- if (InterfaceID != mDNSInterface_Unicast && IsLocalDomain(qname)) { LogInfo("ShouldSuppressQuery: Query not suppressed for %##s, qtype %s, Local question", qname, DNSTypeName(qtype)); return mDNSfalse; }
-
- // Skip Private domains as we have special addresses to get the hosts in the Private domain
- AuthInfo = GetAuthInfoForName_internal(m, qname);
- if (AuthInfo && !AuthInfo->deltime && AuthInfo->AutoTunnel)
- { LogInfo("ShouldSuppressQuery: Query not suppressed for %##s, qtype %s, Private Domain", qname, DNSTypeName(qtype)); return mDNSfalse; }
-
- // Match on Type, Address and InterfaceID
- //
- // Check whether we are looking for a name that ends in .local, then presence of a link-local
- // address on the interface is sufficient.
- for (i = m->HostInterfaces; i; i = i->next)
- {
- if (i->ip.type != iptype) continue;
-
- if (!InterfaceID || (InterfaceID == mDNSInterface_LocalOnly) || (InterfaceID == mDNSInterface_P2P) ||
- (InterfaceID == mDNSInterface_Unicast) || (i->InterfaceID == InterfaceID))
- {
- if (iptype == mDNSAddrType_IPv4 && !mDNSv4AddressIsLoopback(&i->ip.ip.v4) && !mDNSv4AddressIsLinkLocal(&i->ip.ip.v4))
- {
- LogInfo("ShouldSuppressQuery: Query not suppressed for %##s, qtype %s, Local Address %.4a found", qname, DNSTypeName(qtype),
- &i->ip.ip.v4);
- return mDNSfalse;
- }
- else if (iptype == mDNSAddrType_IPv6 &&
- !mDNSv6AddressIsLoopback(&i->ip.ip.v6) &&
- !mDNSv6AddressIsLinkLocal(&i->ip.ip.v6) &&
- !mDNSSameIPv6Address(i->ip.ip.v6, m->AutoTunnelHostAddr) &&
- !mDNSSameIPv6Address(i->ip.ip.v6, m->AutoTunnelRelayAddrOut))
- {
- LogInfo("ShouldSuppressQuery: Query not suppressed for %##s, qtype %s, Local Address %.16a found", qname, DNSTypeName(qtype),
- &i->ip.ip.v6);
- return mDNSfalse;
- }
- }
- }
- LogInfo("ShouldSuppressQuery: Query suppressed for %##s, qtype %s, because no matching interface found", qname, DNSTypeName(qtype));
- return mDNStrue;
- }
+ mDNS_Unlock(m);
+}
+
+mDNSlocal mDNSBool IsPrivateDomain(mDNS *const m, DNSQuestion *q)
+{
+ DomainAuthInfo *AuthInfo;
+ // Skip Private domains as we have special addresses to get the hosts in the Private domain
+ AuthInfo = GetAuthInfoForName_internal(m, &q->qname);
+ if (AuthInfo && !AuthInfo->deltime && AuthInfo->AutoTunnel)
+ {
+ debugf("IsPrivateDomain: %##s true", q->qname.c);
+ return mDNStrue;
+ }
+ else
+ {
+ debugf("IsPrivateDomain: %##s false", q->qname.c);
+ return mDNSfalse;
+ }
+}
+
+// This function takes the DNSServer as a separate argument because sometimes the
+// caller has not yet assigned the DNSServer, but wants to evaluate the SuppressQuery
+// status before switching to it.
+mDNSlocal mDNSBool ShouldSuppressUnicastQuery(mDNS *const m, DNSQuestion *q, DNSServer *d)
+{
+ // Some callers don't check for the qtype
+ if (q->qtype != kDNSType_A && q->qtype != kDNSType_AAAA)
+ {
+ LogInfo("ShouldSuppressUnicastQuery: Query not suppressed for %##s, qtype %s, not A/AAAA type", q->qname.c, DNSTypeName(q->qtype));
+ return mDNSfalse;
+ }
+
+ // Private domains are exempted irrespective of what the DNSServer says
+ if (IsPrivateDomain(m, q))
+ {
+ LogInfo("ShouldSuppressUnicastQuery: Query not suppressed for %##s, qtype %s, Private Domain", q->qname.c, DNSTypeName(q->qtype));
+ return mDNSfalse;
+ }
+
+ if (!d)
+ {
+ LogInfo("ShouldSuppressUnicastQuery: Query suppressed for %##s, qtype %s, as the DNS server is NULL", q->qname.c, DNSTypeName(q->qtype));
+ return mDNStrue;
+ }
+
+ // Check if the DNS Configuration allows A/AAAA queries to be sent
+ if ((q->qtype == kDNSType_A) && (d->req_A))
+ {
+ LogInfo("ShouldSuppressUnicastQuery: Query not suppressed for %##s, qtype %s, DNSServer %##s %#a:%d allows A queries", q->qname.c,
+ DNSTypeName(q->qtype), d->domain.c, &d->addr, mDNSVal16(d->port));
+ return mDNSfalse;
+ }
+ if ((q->qtype == kDNSType_AAAA) && (d->req_AAAA))
+ {
+ LogInfo("ShouldSuppressUnicastQuery: Query not suppressed for %##s, qtype %s, DNSServer %##s %#a:%d allows AAAA queries", q->qname.c,
+ DNSTypeName(q->qtype), d->domain.c, &d->addr, mDNSVal16(d->port));
+ return mDNSfalse;
+ }
+
+ LogInfo("ShouldSuppressUnicastQuery: Query suppressed for %##s, qtype %s, since DNS Configuration does not allow (req_A is %s and req_AAAA is %s)",
+ q->qname.c, DNSTypeName(q->qtype), d->req_A ? "true" : "false", d->req_AAAA ? "true" : "false");
+
+ return mDNStrue;
+}
+
+mDNSlocal mDNSBool ShouldSuppressDotLocalQuery(mDNS *const m, DNSQuestion *q)
+{
+ NetworkInterfaceInfo *intf;
+ AuthRecord *rr;
+ mDNSBool ret;
+
+ // Check to see if there is at least one interface other than loopback and don't suppress
+ // .local questions if you find one. If we have at least one interface, it means that
+ // we can send unicast queries for the .local name and we don't want to suppress
+ // multicast in that case as upper layers don't know how to handle if we return a
+ // negative response for multicast followed by a positive response for unicast.
+ //
+ // Note: we used to check for multicast capable interfaces instead of just any interface
+ // present. That did not work in the case where we have a valid interface for unicast
+ // but not multicast capable e.g., cellular, as we ended up delivering a negative response
+ // first and the upper layer did not wait for the positive response that came later.
+ for (intf = m->HostInterfaces; intf; intf = intf->next)
+ {
+ if (intf->InterfaceActive && !intf->Loopback)
+ {
+ LogInfo("ShouldSuppressDotLocalQuery: Found interface %s, not suppressing", intf->ifname);
+ return mDNSfalse;
+ }
+ }
+
+ // 1. If we find a LocalOnly or P2P record answering this question, then don't suppress it.
+ // Set m->CurrentQuestion as it is required by AnswerQuestionWithLORecord.
+ m->CurrentQuestion = q;
+ ret = AnswerQuestionWithLORecord(m, q, mDNStrue);
+ m->CurrentQuestion = mDNSNULL;
+
+ if (ret)
+ {
+ LogInfo("ShouldSuppressDotLocalQuery: Found LocalOnly record for %##s (%s), not suppressing", q->qname.c,
+ DNSTypeName(q->qtype));
+ return mDNSfalse;
+ }
+
+ // 2. If we find a local AuthRecord answering this question, then don't suppress it.
+ for (rr = m->ResourceRecords; rr; rr = rr->next)
+ {
+ if (ResourceRecordAnswersQuestion(&rr->resrec, q))
+ {
+ LogInfo("ShouldSuppressDotLocalQuery: Found resource record %s for %##s (%s) not suppressing", ARDisplayString(m, rr),
+ q->qname.c, DNSTypeName(q->qtype));
+ return mDNSfalse;
+ }
+ }
+ return mDNStrue;
+}
+
+mDNSlocal mDNSBool ShouldSuppressQuery(mDNS *const m, DNSQuestion *q)
+{
+ if (q->qtype != kDNSType_A && q->qtype != kDNSType_AAAA)
+ {
+ LogInfo("ShouldSuppressQuery: Query not suppressed for %##s, qtype %s, not A/AAAA type", q->qname.c, DNSTypeName(q->qtype));
+ return mDNSfalse;
+ }
+
+ // We still want the ability to be able to listen to the local services and hence
+ // don't fail .local query if we have local records that can potentially answer
+ // the question.
+ if (q->InterfaceID != mDNSInterface_Unicast && IsLocalDomain(&q->qname))
+ {
+ if (!ShouldSuppressDotLocalQuery(m, q))
+ {
+ LogInfo("ShouldSuppressQuery: Query not suppressed for %##s, qtype %s, Local question", q->qname.c, DNSTypeName(q->qtype));
+ return mDNSfalse;
+ }
+ else
+ {
+ LogInfo("ShouldSuppressQuery: Query suppressed for %##s, qtype %s, Local question", q->qname.c, DNSTypeName(q->qtype));
+ return mDNStrue;
+ }
+ }
+
+ return (ShouldSuppressUnicastQuery(m, q, q->qDNSServer));
+}
mDNSlocal void CacheRecordRmvEventsForCurrentQuestion(mDNS *const m, DNSQuestion *q)
- {
- CacheRecord *rr;
- mDNSu32 slot;
- CacheGroup *cg;
-
- slot = HashSlot(&q->qname);
- cg = CacheGroupForName(m, slot, q->qnamehash, &q->qname);
- for (rr = cg ? cg->members : mDNSNULL; rr; rr=rr->next)
- {
- // Don't deliver RMV events for negative records
- if (rr->resrec.RecordType == kDNSRecordTypePacketNegative)
- {
- LogInfo("CacheRecordRmvEventsForCurrentQuestion: CacheRecord %s Suppressing RMV events for question %p %##s (%s), CRActiveQuestion %p, CurrentAnswers %d",
- CRDisplayString(m, rr), q, q->qname.c, DNSTypeName(q->qtype), rr->CRActiveQuestion, q->CurrentAnswers);
- continue;
- }
-
- if (SameNameRecordAnswersQuestion(&rr->resrec, q))
- {
- LogInfo("CacheRecordRmvEventsForCurrentQuestion: Calling AnswerCurrentQuestionWithResourceRecord (RMV) for question %##s using resource record %s LocalAnswers %d",
- q->qname.c, CRDisplayString(m, rr), q->LOAddressAnswers);
-
- q->CurrentAnswers--;
- if (rr->resrec.rdlength > SmallRecordLimit) q->LargeAnswers--;
- if (rr->resrec.RecordType & kDNSRecordTypePacketUniqueMask) q->UniqueAnswers--;
-
- if (rr->CRActiveQuestion == q)
- {
- DNSQuestion *qptr;
- // If this was the active question for this cache entry, it was the one that was
- // responsible for keeping the cache entry fresh when the cache entry was reaching
- // its expiry. We need to handover the responsibility to someone else. Otherwise,
- // when the cache entry is about to expire, we won't find an active question
- // (pointed by CRActiveQuestion) to refresh the cache.
- for (qptr = m->Questions; qptr; qptr=qptr->next)
- if (qptr != q && ActiveQuestion(qptr) && ResourceRecordAnswersQuestion(&rr->resrec, qptr))
- break;
-
- if (qptr)
- LogInfo("CacheRecordRmvEventsForCurrentQuestion: Updating CRActiveQuestion to %p for cache record %s, "
- "Original question CurrentAnswers %d, new question CurrentAnswers %d, SuppressUnusable %d, SuppressQuery %d",
- qptr, CRDisplayString(m,rr), q->CurrentAnswers, qptr->CurrentAnswers, qptr->SuppressUnusable, qptr->SuppressQuery);
-
- rr->CRActiveQuestion = qptr; // Question used to be active; new value may or may not be null
- if (!qptr) m->rrcache_active--; // If no longer active, decrement rrcache_active count
- }
- AnswerCurrentQuestionWithResourceRecord(m, rr, QC_rmv);
- if (m->CurrentQuestion != q) break; // If callback deleted q, then we're finished here
- }
- }
- }
+{
+ CacheRecord *rr;
+ mDNSu32 slot;
+ CacheGroup *cg;
+
+ slot = HashSlot(&q->qname);
+ cg = CacheGroupForName(m, slot, q->qnamehash, &q->qname);
+ for (rr = cg ? cg->members : mDNSNULL; rr; rr=rr->next)
+ {
+ // Don't deliver RMV events for negative records
+ if (rr->resrec.RecordType == kDNSRecordTypePacketNegative)
+ {
+ LogInfo("CacheRecordRmvEventsForCurrentQuestion: CacheRecord %s Suppressing RMV events for question %p %##s (%s), CRActiveQuestion %p, CurrentAnswers %d",
+ CRDisplayString(m, rr), q, q->qname.c, DNSTypeName(q->qtype), rr->CRActiveQuestion, q->CurrentAnswers);
+ continue;
+ }
+
+ if (SameNameRecordAnswersQuestion(&rr->resrec, q))
+ {
+ LogInfo("CacheRecordRmvEventsForCurrentQuestion: Calling AnswerCurrentQuestionWithResourceRecord (RMV) for question %##s using resource record %s LocalAnswers %d",
+ q->qname.c, CRDisplayString(m, rr), q->LOAddressAnswers);
+
+ q->CurrentAnswers--;
+ if (rr->resrec.rdlength > SmallRecordLimit) q->LargeAnswers--;
+ if (rr->resrec.RecordType & kDNSRecordTypePacketUniqueMask) q->UniqueAnswers--;
+
+ if (rr->CRActiveQuestion == q)
+ {
+ DNSQuestion *qptr;
+ // If this was the active question for this cache entry, it was the one that was
+ // responsible for keeping the cache entry fresh when the cache entry was reaching
+ // its expiry. We need to handover the responsibility to someone else. Otherwise,
+ // when the cache entry is about to expire, we won't find an active question
+ // (pointed by CRActiveQuestion) to refresh the cache.
+ for (qptr = m->Questions; qptr; qptr=qptr->next)
+ if (qptr != q && ActiveQuestion(qptr) && ResourceRecordAnswersQuestion(&rr->resrec, qptr))
+ break;
+
+ if (qptr)
+ LogInfo("CacheRecordRmvEventsForCurrentQuestion: Updating CRActiveQuestion to %p for cache record %s, "
+ "Original question CurrentAnswers %d, new question CurrentAnswers %d, SuppressUnusable %d, SuppressQuery %d",
+ qptr, CRDisplayString(m,rr), q->CurrentAnswers, qptr->CurrentAnswers, qptr->SuppressUnusable, qptr->SuppressQuery);
+
+ rr->CRActiveQuestion = qptr; // Question used to be active; new value may or may not be null
+ if (!qptr) m->rrcache_active--; // If no longer active, decrement rrcache_active count
+ }
+ AnswerCurrentQuestionWithResourceRecord(m, rr, QC_rmv);
+ if (m->CurrentQuestion != q) break; // If callback deleted q, then we're finished here
+ }
+ }
+}
mDNSlocal mDNSBool IsQuestionNew(mDNS *const m, DNSQuestion *question)
- {
- DNSQuestion *q;
- for (q = m->NewQuestions; q; q = q->next)
- if (q == question) return mDNStrue;
- return mDNSfalse;
- }
+{
+ DNSQuestion *q;
+ for (q = m->NewQuestions; q; q = q->next)
+ if (q == question) return mDNStrue;
+ return mDNSfalse;
+}
mDNSlocal mDNSBool LocalRecordRmvEventsForQuestion(mDNS *const m, DNSQuestion *q)
- {
- AuthRecord *rr;
- mDNSu32 slot;
- AuthGroup *ag;
-
- if (m->CurrentQuestion)
- LogMsg("LocalRecordRmvEventsForQuestion: ERROR m->CurrentQuestion already set: %##s (%s)",
- m->CurrentQuestion->qname.c, DNSTypeName(m->CurrentQuestion->qtype));
-
- if (IsQuestionNew(m, q))
- {
- LogInfo("LocalRecordRmvEventsForQuestion: New Question %##s (%s)", q->qname.c, DNSTypeName(q->qtype));
- return mDNStrue;
- }
- m->CurrentQuestion = q;
- slot = AuthHashSlot(&q->qname);
- ag = AuthGroupForName(&m->rrauth, slot, q->qnamehash, &q->qname);
- if (ag)
- {
- for (rr = ag->members; rr; rr=rr->next)
- // Filter the /etc/hosts records - LocalOnly, Unique, A/AAAA/CNAME
- if (LORecordAnswersAddressType(rr) && LocalOnlyRecordAnswersQuestion(rr, q))
- {
- LogInfo("LocalRecordRmvEventsForQuestion: Delivering possible Rmv events with record %s",
- ARDisplayString(m, rr));
- if (q->CurrentAnswers <= 0 || q->LOAddressAnswers <= 0)
- {
- LogMsg("LocalRecordRmvEventsForQuestion: ERROR!! CurrentAnswers or LOAddressAnswers is zero %p %##s"
- " (%s) CurrentAnswers %d, LOAddressAnswers %d", q, q->qname.c, DNSTypeName(q->qtype),
- q->CurrentAnswers, q->LOAddressAnswers);
- continue;
- }
- AnswerLocalQuestionWithLocalAuthRecord(m, rr, QC_rmv); // MUST NOT dereference q again
- if (m->CurrentQuestion != q) { m->CurrentQuestion = mDNSNULL; return mDNSfalse; }
- }
- }
- m->CurrentQuestion = mDNSNULL;
- return mDNStrue;
- }
+{
+ AuthRecord *rr;
+ mDNSu32 slot;
+ AuthGroup *ag;
+
+ if (m->CurrentQuestion)
+ LogMsg("LocalRecordRmvEventsForQuestion: ERROR m->CurrentQuestion already set: %##s (%s)",
+ m->CurrentQuestion->qname.c, DNSTypeName(m->CurrentQuestion->qtype));
+
+ if (IsQuestionNew(m, q))
+ {
+ LogInfo("LocalRecordRmvEventsForQuestion: New Question %##s (%s)", q->qname.c, DNSTypeName(q->qtype));
+ return mDNStrue;
+ }
+ m->CurrentQuestion = q;
+ slot = AuthHashSlot(&q->qname);
+ ag = AuthGroupForName(&m->rrauth, slot, q->qnamehash, &q->qname);
+ if (ag)
+ {
+ for (rr = ag->members; rr; rr=rr->next)
+ // Filter the /etc/hosts records - LocalOnly, Unique, A/AAAA/CNAME
+ if (UniqueLocalOnlyRecord(rr) && LocalOnlyRecordAnswersQuestion(rr, q))
+ {
+ LogInfo("LocalRecordRmvEventsForQuestion: Delivering possible Rmv events with record %s",
+ ARDisplayString(m, rr));
+ if (q->CurrentAnswers <= 0 || q->LOAddressAnswers <= 0)
+ {
+ LogMsg("LocalRecordRmvEventsForQuestion: ERROR!! CurrentAnswers or LOAddressAnswers is zero %p %##s"
+ " (%s) CurrentAnswers %d, LOAddressAnswers %d", q, q->qname.c, DNSTypeName(q->qtype),
+ q->CurrentAnswers, q->LOAddressAnswers);
+ continue;
+ }
+ AnswerLocalQuestionWithLocalAuthRecord(m, rr, QC_rmv); // MUST NOT dereference q again
+ if (m->CurrentQuestion != q) { m->CurrentQuestion = mDNSNULL; return mDNSfalse; }
+ }
+ }
+ m->CurrentQuestion = mDNSNULL;
+ return mDNStrue;
+}
// Returns false if the question got deleted while delivering the RMV events
-// The caller should handle the case
+// The caller should handle the case
mDNSlocal mDNSBool CacheRecordRmvEventsForQuestion(mDNS *const m, DNSQuestion *q)
- {
- if (m->CurrentQuestion)
- LogMsg("CacheRecordRmvEventsForQuestion: ERROR m->CurrentQuestion already set: %##s (%s)",
- m->CurrentQuestion->qname.c, DNSTypeName(m->CurrentQuestion->qtype));
-
- // If it is a new question, we have not delivered any ADD events yet. So, don't deliver RMV events.
- // If this question was answered using local auth records, then you can't deliver RMVs using cache
- if (!IsQuestionNew(m, q) && !q->LOAddressAnswers)
- {
- m->CurrentQuestion = q;
- CacheRecordRmvEventsForCurrentQuestion(m, q);
- if (m->CurrentQuestion != q) { m->CurrentQuestion = mDNSNULL; return mDNSfalse; }
- m->CurrentQuestion = mDNSNULL;
- }
- else { LogInfo("CacheRecordRmvEventsForQuestion: Question %p %##s (%s) is a new question", q, q->qname.c, DNSTypeName(q->qtype)); }
- return mDNStrue;
- }
+{
+ if (m->CurrentQuestion)
+ LogMsg("CacheRecordRmvEventsForQuestion: ERROR m->CurrentQuestion already set: %##s (%s)",
+ m->CurrentQuestion->qname.c, DNSTypeName(m->CurrentQuestion->qtype));
+
+ // If it is a new question, we have not delivered any ADD events yet. So, don't deliver RMV events.
+ // If this question was answered using local auth records, then you can't deliver RMVs using cache
+ if (!IsQuestionNew(m, q) && !q->LOAddressAnswers)
+ {
+ m->CurrentQuestion = q;
+ CacheRecordRmvEventsForCurrentQuestion(m, q);
+ if (m->CurrentQuestion != q) { m->CurrentQuestion = mDNSNULL; return mDNSfalse; }
+ m->CurrentQuestion = mDNSNULL;
+ }
+ else { LogInfo("CacheRecordRmvEventsForQuestion: Question %p %##s (%s) is a new question", q, q->qname.c, DNSTypeName(q->qtype)); }
+ return mDNStrue;
+}
+
+mDNSlocal void SuppressStatusChanged(mDNS *const m, DNSQuestion *q, DNSQuestion **restart)
+{
+ // NOTE: CacheRecordRmvEventsForQuestion will not generate RMV events for queries that have non-zero
+ // LOAddressAnswers. Hence it is important that we call CacheRecordRmvEventsForQuestion before
+ // LocalRecordRmvEventsForQuestion (which decrements LOAddressAnswers)
+ if (q->SuppressQuery)
+ {
+ q->SuppressQuery = mDNSfalse;
+ if (!CacheRecordRmvEventsForQuestion(m, q))
+ {
+ LogInfo("SuppressStatusChanged: Question deleted while delivering RMV events from cache");
+ return;
+ }
+ q->SuppressQuery = mDNStrue;
+ }
+
+ // SuppressUnusable does not affect questions that are answered from the local records (/etc/hosts)
+ // and SuppressQuery status does not mean anything for these questions. As we are going to stop the
+ // question below, we need to deliver the RMV events so that the ADDs that will be delivered during
+ // the restart will not be a duplicate ADD
+ if (!LocalRecordRmvEventsForQuestion(m, q))
+ {
+ LogInfo("SuppressStatusChanged: Question deleted while delivering RMV events from Local AuthRecords");
+ return;
+ }
+
+ // There are two cases here.
+ //
+ // 1. Previously it was suppressed and now it is not suppressed, restart the question so
+ // that it will start as a new question. Note that we can't just call ActivateUnicastQuery
+ // because when we get the response, if we had entries in the cache already, it will not answer
+ // this question if the cache entry did not change. Hence, we need to restart
+ // the query so that it can be answered from the cache.
+ //
+ // 2. Previously it was not suppressed and now it is suppressed. We need to restart the questions
+ // so that we redo the duplicate checks in mDNS_StartQuery_internal. A SuppressUnusable question
+ // is a duplicate of non-SuppressUnusable question if it is not suppressed (SuppressQuery is false).
+ // A SuppressUnusable question is not a duplicate of non-SuppressUnusable question if it is suppressed
+ // (SuppressQuery is true). The reason for this is that when a question is suppressed, we want an
+ // immediate response and not want to be blocked behind a question that is querying DNS servers. When
+ // the question is not suppressed, we don't want two active questions sending packets on the wire.
+ // This affects both efficiency and also the current design where there is only one active question
+ // pointed to from a cache entry.
+ //
+ // We restart queries in a two step process by first calling stop and build a temporary list which we
+ // will restart at the end. The main reason for the two step process is to handle duplicate questions.
+ // If there are duplicate questions, calling stop inherits the values from another question on the list (which
+ // will soon become the real question) including q->ThisQInterval which might be zero if it was
+ // suppressed before. At the end when we have restarted all questions, none of them is active as each
+ // inherits from one another and we need to reactivate one of the questions here which is a little hacky.
+ //
+ // It is much cleaner and less error prone to build a list of questions and restart at the end.
+
+ LogInfo("SuppressStatusChanged: Stop question %p %##s (%s)", q, q->qname.c, DNSTypeName(q->qtype));
+ mDNS_StopQuery_internal(m, q);
+ q->next = *restart;
+ *restart = q;
+}
// The caller should hold the lock
mDNSexport void CheckSuppressUnusableQuestions(mDNS *const m)
- {
- DNSQuestion *q;
- DNSQuestion *restart = mDNSNULL;
-
- // We look through all questions including new questions. During network change events,
- // we potentially restart questions here in this function that ends up as new questions,
- // which may be suppressed at this instance. Before it is handled we get another network
- // event that changes the status e.g., address becomes available. If we did not process
- // new questions, we would never change its SuppressQuery status.
- //
- // CurrentQuestion is used by RmvEventsForQuestion below. While delivering RMV events, the
- // application callback can potentially stop the current question (detected by CurrentQuestion) or
- // *any* other question which could be the next one that we may process here. RestartQuestion
- // points to the "next" question which will be automatically advanced in mDNS_StopQuery_internal
- // if the "next" question is stopped while the CurrentQuestion is stopped
- if (m->RestartQuestion)
- LogMsg("CheckSuppressUnusableQuestions: ERROR!! m->RestartQuestion already set: %##s (%s)",
- m->RestartQuestion->qname.c, DNSTypeName(m->RestartQuestion->qtype));
- m->RestartQuestion = m->Questions;
- while (m->RestartQuestion)
- {
- q = m->RestartQuestion;
- m->RestartQuestion = q->next;
- if (!mDNSOpaque16IsZero(q->TargetQID) && q->SuppressUnusable)
- {
- mDNSBool old = q->SuppressQuery;
- q->SuppressQuery = ShouldSuppressQuery(m, &q->qname, q->qtype, q->InterfaceID);
- if (q->SuppressQuery != old)
- {
- // NOTE: CacheRecordRmvEventsForQuestion will not generate RMV events for queries that have non-zero
- // LOddressAnswers. Hence it is important that we call CacheRecordRmvEventsForQuestion before
- // LocalRecordRmvEventsForQuestion (which decrements LOAddressAnswers)
-
- if (q->SuppressQuery)
- {
- // Previously it was not suppressed, Generate RMV events for the ADDs that we might have delivered before
- // followed by a negative cache response. Temporarily turn off suppression so that
- // AnswerCurrentQuestionWithResourceRecord can answer the question
- q->SuppressQuery = mDNSfalse;
- if (!CacheRecordRmvEventsForQuestion(m, q)) { LogInfo("CheckSuppressUnusableQuestions: Question deleted while delivering RMV events"); continue; }
- q->SuppressQuery = mDNStrue;
- }
-
- // SuppressUnusable does not affect questions that are answered from the local records (/etc/hosts)
- // and SuppressQuery status does not mean anything for these questions. As we are going to stop the
- // question below, we need to deliver the RMV events so that the ADDs that will be delivered during
- // the restart will not be a duplicate ADD
- if (!LocalRecordRmvEventsForQuestion(m, q)) { LogInfo("CheckSuppressUnusableQuestions: Question deleted while delivering RMV events"); continue; }
-
- // There are two cases here.
- //
- // 1. Previously it was suppressed and now it is not suppressed, restart the question so
- // that it will start as a new question. Note that we can't just call ActivateUnicastQuery
- // because when we get the response, if we had entries in the cache already, it will not answer
- // this question if the cache entry did not change. Hence, we need to restart
- // the query so that it can be answered from the cache.
- //
- // 2. Previously it was not suppressed and now it is suppressed. We need to restart the questions
- // so that we redo the duplicate checks in mDNS_StartQuery_internal. A SuppressUnusable question
- // is a duplicate of non-SuppressUnusable question if it is not suppressed (SuppressQuery is false).
- // A SuppressUnusable question is not a duplicate of non-SuppressUnusable question if it is suppressed
- // (SuppressQuery is true). The reason for this is that when a question is suppressed, we want an
- // immediate response and not want to be blocked behind a question that is querying DNS servers. When
- // the question is not suppressed, we don't want two active questions sending packets on the wire.
- // This affects both efficiency and also the current design where there is only one active question
- // pointed to from a cache entry.
- //
- // We restart queries in a two step process by first calling stop and build a temporary list which we
- // will restart at the end. The main reason for the two step process is to handle duplicate questions.
- // If there are duplicate questions, calling stop inherits the values from another question on the list (which
- // will soon become the real question) including q->ThisQInterval which might be zero if it was
- // suppressed before. At the end when we have restarted all questions, none of them is active as each
- // inherits from one another and we need to reactivate one of the questions here which is a little hacky.
- //
- // It is much cleaner and less error prone to build a list of questions and restart at the end.
-
- LogInfo("CheckSuppressUnusableQuestions: Stop question %p %##s (%s)", q, q->qname.c, DNSTypeName(q->qtype));
- mDNS_StopQuery_internal(m, q);
- q->next = restart;
- restart = q;
- }
- }
- }
- while (restart)
- {
- q = restart;
- restart = restart->next;
- q->next = mDNSNULL;
- LogInfo("CheckSuppressUnusableQuestions: Start question %p %##s (%s)", q, q->qname.c, DNSTypeName(q->qtype));
- mDNS_StartQuery_internal(m, q);
- }
- }
+{
+ DNSQuestion *q;
+ DNSQuestion *restart = mDNSNULL;
+
+ // We look through all questions including new questions. During network change events,
+ // we potentially restart questions here in this function that ends up as new questions,
+ // which may be suppressed at this instance. Before it is handled we get another network
+ // event that changes the status e.g., address becomes available. If we did not process
+ // new questions, we would never change its SuppressQuery status.
+ //
+ // CurrentQuestion is used by RmvEventsForQuestion below. While delivering RMV events, the
+ // application callback can potentially stop the current question (detected by CurrentQuestion) or
+ // *any* other question which could be the next one that we may process here. RestartQuestion
+ // points to the "next" question which will be automatically advanced in mDNS_StopQuery_internal
+ // if the "next" question is stopped while the CurrentQuestion is stopped
+ if (m->RestartQuestion)
+ LogMsg("CheckSuppressUnusableQuestions: ERROR!! m->RestartQuestion already set: %##s (%s)",
+ m->RestartQuestion->qname.c, DNSTypeName(m->RestartQuestion->qtype));
+ m->RestartQuestion = m->Questions;
+ while (m->RestartQuestion)
+ {
+ q = m->RestartQuestion;
+ m->RestartQuestion = q->next;
+ if (q->SuppressUnusable)
+ {
+ mDNSBool old = q->SuppressQuery;
+ q->SuppressQuery = ShouldSuppressQuery(m, q);
+ if (q->SuppressQuery != old)
+ {
+ // Previously it was not suppressed, Generate RMV events for the ADDs that we might have delivered before
+ // followed by a negative cache response. Temporarily turn off suppression so that
+ // AnswerCurrentQuestionWithResourceRecord can answer the question
+ SuppressStatusChanged(m, q, &restart);
+ }
+ }
+ }
+ while (restart)
+ {
+ q = restart;
+ restart = restart->next;
+ q->next = mDNSNULL;
+ LogInfo("CheckSuppressUnusableQuestions: Start question %p %##s (%s)", q, q->qname.c, DNSTypeName(q->qtype));
+ mDNS_StartQuery_internal(m, q);
+ }
+}
+
+mDNSlocal void RestartUnicastQuestions(mDNS *const m)
+{
+ DNSQuestion *q;
+ DNSQuestion *restart = mDNSNULL;
+
+ if (m->RestartQuestion)
+ LogMsg("RestartUnicastQuestions: ERROR!! m->RestartQuestion already set: %##s (%s)",
+ m->RestartQuestion->qname.c, DNSTypeName(m->RestartQuestion->qtype));
+ m->RestartQuestion = m->Questions;
+ while (m->RestartQuestion)
+ {
+ q = m->RestartQuestion;
+ m->RestartQuestion = q->next;
+ if (q->Restart)
+ {
+ if (mDNSOpaque16IsZero(q->TargetQID))
+ LogMsg("RestartUnicastQuestions: ERROR!! Restart set for multicast question %##s (%s)", q->qname.c, DNSTypeName(q->qtype));
+
+ q->Restart = 0;
+ SuppressStatusChanged(m, q, &restart);
+ }
+ }
+ while (restart)
+ {
+ q = restart;
+ restart = restart->next;
+ q->next = mDNSNULL;
+ LogInfo("RestartUnicastQuestions: Start question %p %##s (%s)", q, q->qname.c, DNSTypeName(q->qtype));
+ mDNS_StartQuery_internal(m, q);
+ }
+}
-mDNSexport mStatus mDNS_StartQuery_internal(mDNS *const m, DNSQuestion *const question)
- {
- if (question->Target.type && !ValidQuestionTarget(question))
- {
- LogMsg("mDNS_StartQuery_internal: Warning! Target.type = %ld port = %u (Client forgot to initialize before calling mDNS_StartQuery? for question %##s)",
- question->Target.type, mDNSVal16(question->TargetPort), question->qname.c);
- question->Target.type = mDNSAddrType_None;
- }
- if (!question->Target.type) question->TargetPort = zeroIPPort; // If no question->Target specified clear TargetPort
+// ValidateParameters() is called by mDNS_StartQuery_internal() to check the client parameters of
+// DNS Question that are already set by the client before calling mDNS_StartQuery()
+mDNSlocal mStatus ValidateParameters(mDNS *const m, DNSQuestion *const question)
+{
- question->TargetQID =
-#ifndef UNICAST_DISABLED
- (question->Target.type || Question_uDNS(question)) ? mDNS_NewMessageID(m) :
-#endif // UNICAST_DISABLED
- zeroID;
+ if (question->Target.type && !ValidQuestionTarget(question))
+ {
+ LogMsg("ValidateParameters: Warning! Target.type = %ld port = %u (Client forgot to initialize before calling mDNS_StartQuery? for question %##s)",
+ question->Target.type, mDNSVal16(question->TargetPort), question->qname.c);
+ question->Target.type = mDNSAddrType_None;
+ }
- debugf("mDNS_StartQuery: %##s (%s)", question->qname.c, DNSTypeName(question->qtype));
+ // If no question->Target specified, clear TargetPort
+ if (!question->Target.type)
+ question->TargetPort = zeroIPPort;
+
+ if (!ValidateDomainName(&question->qname))
+ {
+ LogMsg("ValidateParameters: Attempt to start query with invalid qname %##s (%s)", question->qname.c, DNSTypeName(question->qtype));
+ return(mStatus_Invalid);
+ }
- if (m->rrcache_size == 0) // Can't do queries if we have no cache space allocated
- return(mStatus_NoCache);
+ // If this question is referencing a specific interface, verify it exists
+ if (question->InterfaceID && question->InterfaceID != mDNSInterface_LocalOnly && question->InterfaceID != mDNSInterface_Unicast && question->InterfaceID != mDNSInterface_P2P)
+ {
+ NetworkInterfaceInfo *intf = FirstInterfaceForID(m, question->InterfaceID);
+ if (!intf)
+ LogInfo("ValidateParameters: Note: InterfaceID %d for question %##s (%s) not currently found in active interface list",
+ (uint32_t)question->InterfaceID, question->qname.c, DNSTypeName(question->qtype));
+ }
+
+ return(mStatus_NoError);
+}
+
+// InitDNSConfig() is called by InitCommonState() to initialize the DNS configuration of the Question.
+// These are a subset of the internal uDNS fields. Must be done before ShouldSuppressQuery() & mDNS_PurgeForQuestion()
+mDNSlocal void InitDNSConfig(mDNS *const m, DNSQuestion *const question)
+{
+ // First reset all DNS Configuration
+ question->qDNSServer = mDNSNULL;
+ question->validDNSServers = zeroOpaque64;
+ question->triedAllServersOnce = 0;
+ question->noServerResponse = 0;
+ question->StopTime = 0;
+
+ // Need not initialize the DNS Configuration for Local Only OR P2P Questions
+ if (question->InterfaceID == mDNSInterface_LocalOnly || question->InterfaceID == mDNSInterface_P2P)
+ return;
+ // Proceed to initialize DNS Configuration (some are set in SetValidDNSServers())
+ if (!mDNSOpaque16IsZero(question->TargetQID))
+ {
+ mDNSu32 timeout = SetValidDNSServers(m, question);
+ // We set the timeout whenever mDNS_StartQuery_internal is called. This means if we have
+ // a networking change/search domain change that calls this function again we keep
+ // reinitializing the timeout value which means it may never timeout. If this becomes
+ // a common case in the future, we can easily fix this by adding extra state that
+ // indicates that we have already set the StopTime.
+ //
+ // Note that we set the timeout for all questions. If this turns out to be a duplicate,
+ // it gets a full timeout value even if the original question times out earlier.
+ if (question->TimeoutQuestion)
+ {
+ question->StopTime = NonZeroTime(m->timenow + timeout * mDNSPlatformOneSecond);
+ LogInfo("InitDNSConfig: Setting StopTime on question %p %##s (%s)", question, question->qname.c, DNSTypeName(question->qtype));
+ }
+
+ question->qDNSServer = GetServerForQuestion(m, question);
+ LogInfo("InitDNSConfig: question %p %##s (%s) Timeout %d, DNS Server %#a:%d",
+ question, question->qname.c, DNSTypeName(question->qtype), timeout,
+ question->qDNSServer ? &question->qDNSServer->addr : mDNSNULL,
+ mDNSVal16(question->qDNSServer ? question->qDNSServer->port : zeroIPPort));
+ }
+ else
+ {
+ if (question->TimeoutQuestion)
+ question->StopTime = NonZeroTime(m->timenow + GetTimeoutForMcastQuestion(m, question) * mDNSPlatformOneSecond);
+ }
+ // Set StopTime here since it is a part of DNS Configuration
+ if (question->StopTime)
+ SetNextQueryStopTime(m, question);
+ // SetNextQueryTime() need not be initialized for LocalOnly OR P2P Questions since those questions
+ // will never be transmitted on the wire. Hence we call SetNextQueryTime() here.
+ SetNextQueryTime(m,question);
+}
+
+// InitCommonState() is called by mDNS_StartQuery_internal() to initialize the common(uDNS/mDNS) internal
+// state fields of the DNS Question. These are independent of the Client layer.
+mDNSlocal mDNSBool InitCommonState(mDNS *const m, DNSQuestion *const question)
+{
+ mDNSBool purge;
+ int i;
+
+ // Note: In the case where we already have the answer to this question in our cache, that may be all the client
+ // wanted, and they may immediately cancel their question. In this case, sending an actual query on the wire would
+ // be a waste. For that reason, we schedule our first query to go out in half a second (InitialQuestionInterval).
+ // If AnswerNewQuestion() finds that we have *no* relevant answers currently in our cache, then it will accelerate
+ // that to go out immediately.
+ question->next = mDNSNULL;
+ // ThisQInterval should be initialized before any memory allocations occur. If malloc
+ // debugging is turned on within mDNSResponder (see mDNSDebug.h for details) it validates
+ // the question list to check if ThisQInterval is negative which means the question has been
+ // stopped and can't be on the list. The question is already on the list and ThisQInterval
+ // can be negative if the caller just stopped it and starting it again. Hence, it always has to
+ // be initialized. CheckForSoonToExpireRecords below prints the cache records when logging is
+ // turned ON which can allocate memory e.g., base64 encoding, in the case of DNSSEC.
+ question->ThisQInterval = InitialQuestionInterval; // MUST be > zero for an active question
+ question->qnamehash = DomainNameHashValue(&question->qname);
+ question->DelayAnswering = CheckForSoonToExpireRecords(m, &question->qname, question->qnamehash, HashSlot(&question->qname), &purge);
+ question->LastQTime = m->timenow;
+ question->ExpectUnicastResp = 0;
+ question->LastAnswerPktNum = m->PktNum;
+ question->RecentAnswerPkts = 0;
+ question->CurrentAnswers = 0;
+
+#if APPLE_OSX_mDNSResponder
+
+// Initial browse threshold used by Finder.
+#define mDNSFinderBrowseThreshold 20
+
+ // Set the threshold at which we move to a passive browse state,
+ // not actively sending queries.
+ if (question->flags & kDNSServiceFlagsThresholdOne)
+ question->BrowseThreshold = 1;
+ else if (question->flags & kDNSServiceFlagsThresholdFinder)
+ question->BrowseThreshold = mDNSFinderBrowseThreshold;
+ else
+ question->BrowseThreshold = 0;
+
+#else // APPLE_OSX_mDNSResponder
+ question->BrowseThreshold = 0;
+#endif // APPLE_OSX_mDNSResponder
+ question->CachedAnswerNeedsUpdate = mDNSfalse;
+
+ question->LargeAnswers = 0;
+ question->UniqueAnswers = 0;
+ question->LOAddressAnswers = 0;
+ question->FlappingInterface1 = mDNSNULL;
+ question->FlappingInterface2 = mDNSNULL;
+
+ // if kDNSServiceFlagsServiceIndex flag is SET by the client, then do NOT call mDNSPlatformGetServiceID()
+ // since we would already have the question->ServiceID in that case.
+ if (!(question->flags & kDNSServiceFlagsServiceIndex))
+ question->ServiceID = mDNSPlatformGetServiceID(m, question);
else
- {
- int i;
- DNSQuestion **q;
-
- if (!ValidateDomainName(&question->qname))
- {
- LogMsg("Attempt to start query with invalid qname %##s (%s)", question->qname.c, DNSTypeName(question->qtype));
- return(mStatus_Invalid);
- }
-
- // Note: It important that new questions are appended at the *end* of the list, not prepended at the start
- q = &m->Questions;
- if (question->InterfaceID == mDNSInterface_LocalOnly || question->InterfaceID == mDNSInterface_P2P) q = &m->LocalOnlyQuestions;
- while (*q && *q != question) q=&(*q)->next;
-
- if (*q)
- {
- LogMsg("Error! Tried to add a question %##s (%s) %p that's already in the active list",
- question->qname.c, DNSTypeName(question->qtype), question);
- return(mStatus_AlreadyRegistered);
- }
-
- *q = question;
-
- // If this question is referencing a specific interface, verify it exists
- if (question->InterfaceID && question->InterfaceID != mDNSInterface_LocalOnly && question->InterfaceID != mDNSInterface_Unicast && question->InterfaceID != mDNSInterface_P2P)
- {
- NetworkInterfaceInfo *intf = FirstInterfaceForID(m, question->InterfaceID);
- if (!intf)
- LogMsg("Note: InterfaceID %p for question %##s (%s) not currently found in active interface list",
- question->InterfaceID, question->qname.c, DNSTypeName(question->qtype));
- }
-
- // Note: In the case where we already have the answer to this question in our cache, that may be all the client
- // wanted, and they may immediately cancel their question. In this case, sending an actual query on the wire would
- // be a waste. For that reason, we schedule our first query to go out in half a second (InitialQuestionInterval).
- // If AnswerNewQuestion() finds that we have *no* relevant answers currently in our cache, then it will accelerate
- // that to go out immediately.
- question->next = mDNSNULL;
- question->qnamehash = DomainNameHashValue(&question->qname); // MUST do this before FindDuplicateQuestion()
- question->DelayAnswering = CheckForSoonToExpireRecords(m, &question->qname, question->qnamehash, HashSlot(&question->qname));
- question->LastQTime = m->timenow;
- question->ThisQInterval = InitialQuestionInterval; // MUST be > zero for an active question
- question->ExpectUnicastResp = 0;
- question->LastAnswerPktNum = m->PktNum;
- question->RecentAnswerPkts = 0;
- question->CurrentAnswers = 0;
- question->LargeAnswers = 0;
- question->UniqueAnswers = 0;
- question->LOAddressAnswers = 0;
- question->FlappingInterface1 = mDNSNULL;
- question->FlappingInterface2 = mDNSNULL;
- // Must do AuthInfo and SuppressQuery before calling FindDuplicateQuestion()
- question->AuthInfo = GetAuthInfoForQuestion(m, question);
- if (question->SuppressUnusable)
- question->SuppressQuery = ShouldSuppressQuery(m, &question->qname, question->qtype, question->InterfaceID);
- else
- question->SuppressQuery = 0;
- question->DuplicateOf = FindDuplicateQuestion(m, question);
- question->NextInDQList = mDNSNULL;
- question->SendQNow = mDNSNULL;
- question->SendOnAll = mDNSfalse;
- question->RequestUnicast = 0;
- question->LastQTxTime = m->timenow;
- question->CNAMEReferrals = 0;
-
- // We'll create our question->LocalSocket on demand, if needed.
- // We won't need one for duplicate questions, or from questions answered immediately out of the cache.
- // We also don't need one for LLQs because (when we're using NAT) we want them all to share a single
- // NAT mapping for receiving inbound add/remove events.
- question->LocalSocket = mDNSNULL;
- question->deliverAddEvents = mDNSfalse;
- question->qDNSServer = mDNSNULL;
- question->unansweredQueries = 0;
- question->nta = mDNSNULL;
- question->servAddr = zeroAddr;
- question->servPort = zeroIPPort;
- question->tcp = mDNSNULL;
- question->NoAnswer = NoAnswer_Normal;
-
- question->state = LLQ_InitialRequest;
- question->ReqLease = 0;
- question->expire = 0;
- question->ntries = 0;
- question->id = zeroOpaque64;
- question->validDNSServers = zeroOpaque64;
- question->triedAllServersOnce = 0;
- question->noServerResponse = 0;
- question->StopTime = 0;
- if (question->WakeOnResolve)
- {
- question->WakeOnResolveCount = InitialWakeOnResolveCount;
- mDNS_PurgeBeforeResolve(m, question);
- }
- else
- question->WakeOnResolveCount = 0;
-
- if (question->DuplicateOf) question->AuthInfo = question->DuplicateOf->AuthInfo;
-
- for (i=0; i<DupSuppressInfoSize; i++)
- question->DupSuppress[i].InterfaceID = mDNSNULL;
-
- debugf("mDNS_StartQuery: Question %##s (%s) Interface %p Now %d Send in %d Answer in %d (%p) %s (%p)",
- question->qname.c, DNSTypeName(question->qtype), question->InterfaceID, m->timenow,
- NextQSendTime(question) - m->timenow,
- question->DelayAnswering ? question->DelayAnswering - m->timenow : 0,
- question, question->DuplicateOf ? "duplicate of" : "not duplicate", question->DuplicateOf);
-
- if (question->DelayAnswering)
- LogInfo("mDNS_StartQuery_internal: Delaying answering for %d ticks while cache stabilizes for %##s (%s)",
- question->DelayAnswering - m->timenow, question->qname.c, DNSTypeName(question->qtype));
-
- if (question->InterfaceID == mDNSInterface_LocalOnly || question->InterfaceID == mDNSInterface_P2P)
- {
- if (!m->NewLocalOnlyQuestions) m->NewLocalOnlyQuestions = question;
- }
- else
- {
- if (!m->NewQuestions) m->NewQuestions = question;
-
- // If the question's id is non-zero, then it's Wide Area
- // MUST NOT do this Wide Area setup until near the end of
- // mDNS_StartQuery_internal -- this code may itself issue queries (e.g. SOA,
- // NS, etc.) and if we haven't finished setting up our own question and setting
- // m->NewQuestions if necessary then we could end up recursively re-entering
- // this routine with the question list data structures in an inconsistent state.
- if (!mDNSOpaque16IsZero(question->TargetQID))
- {
- // Duplicate questions should have the same DNSServers so that when we find
- // a matching resource record, all of them get the answers. Calling GetServerForQuestion
- // for the duplicate question may get a different DNS server from the original question
- mDNSu32 timeout = SetValidDNSServers(m, question);
- // We set the timeout whenever mDNS_StartQuery_internal is called. This means if we have
- // a networking change/search domain change that calls this function again we keep
- // reinitializing the timeout value which means it may never timeout. If this becomes
- // a common case in the future, we can easily fix this by adding extra state that
- // indicates that we have already set the StopTime.
- if (question->TimeoutQuestion)
- question->StopTime = NonZeroTime(m->timenow + timeout * mDNSPlatformOneSecond);
- if (question->DuplicateOf)
- {
- question->validDNSServers = question->DuplicateOf->validDNSServers;
- question->qDNSServer = question->DuplicateOf->qDNSServer;
- LogInfo("mDNS_StartQuery_internal: Duplicate question %p (%p) %##s (%s), Timeout %d, DNS Server %#a:%d",
- question, question->DuplicateOf, question->qname.c, DNSTypeName(question->qtype), timeout,
- question->qDNSServer ? &question->qDNSServer->addr : mDNSNULL,
- mDNSVal16(question->qDNSServer ? question->qDNSServer->port : zeroIPPort));
- }
- else
- {
- question->qDNSServer = GetServerForQuestion(m, question);
- LogInfo("mDNS_StartQuery_internal: question %p %##s (%s) Timeout %d, DNS Server %#a:%d",
- question, question->qname.c, DNSTypeName(question->qtype), timeout,
- question->qDNSServer ? &question->qDNSServer->addr : mDNSNULL,
- mDNSVal16(question->qDNSServer ? question->qDNSServer->port : zeroIPPort));
- }
- ActivateUnicastQuery(m, question, mDNSfalse);
-
- // If long-lived query, and we don't have our NAT mapping active, start it now
- if (question->LongLived && !m->LLQNAT.clientContext)
- {
- m->LLQNAT.Protocol = NATOp_MapUDP;
- m->LLQNAT.IntPort = m->UnicastPort4;
- m->LLQNAT.RequestedPort = m->UnicastPort4;
- m->LLQNAT.clientCallback = LLQNATCallback;
- m->LLQNAT.clientContext = (void*)1; // Means LLQ NAT Traversal is active
- mDNS_StartNATOperation_internal(m, &m->LLQNAT);
- }
-
+ LogInfo("InitCommonState: Query for %##s (%s), PID[%d], ServiceID %d is already set by client", question->qname.c,
+ DNSTypeName(question->qtype), question->pid, question->ServiceID);
+
+ InitDNSConfig(m, question);
+
+ question->AuthInfo = GetAuthInfoForQuestion(m, question);
+ question->SuppressQuery = 0;
+ if (question->SuppressUnusable)
+ question->SuppressQuery = ShouldSuppressQuery(m, question);
+
+ // If ServiceID is 0 or the policy disallows making DNS requests,
+ // set DisallowPID
+ question->DisallowPID = (question->ServiceID == 0 || (mDNSPlatformAllowPID(m, question) == 0));
+ if (question->DisallowPID)
+ LogInfo("InitCommonState: Query suppressed for %##s (%s), PID %d/ServiceID %d not allowed", question->qname.c,
+ DNSTypeName(question->qtype), question->pid, question->ServiceID);
+
+ question->NextInDQList = mDNSNULL;
+ question->SendQNow = mDNSNULL;
+ question->SendOnAll = mDNSfalse;
+
+#if mDNS_REQUEST_UNICAST_RESPONSE
+ question->RequestUnicast = SET_QU_IN_FIRST_FOUR_QUERIES;
+#else // mDNS_REQUEST_UNICAST_RESPONSE
+ question->RequestUnicast = SET_QU_IN_FIRST_QUERY;
+#endif // mDNS_REQUEST_UNICAST_RESPONSE
+
+#if APPLE_OSX_mDNSResponder
+ // Request unicast response for first 4 queries to increase
+ // reliability in an environment with high multicast packet loss.
+ // Must set to one more than the number of unicast queries you want, since SendQueries()
+ // decrements it before calling BuildQuestion() which acts on it.
+ if (question->flags & kDNSServiceFlagsUnicastResponse)
+ {
+ question->RequestUnicast = SET_QU_IN_FIRST_FOUR_QUERIES;
+ LogInfo("InitCommonState: setting RequestUnicast = %d for %##s (%s)", question->RequestUnicast, question->qname.c,
+ DNSTypeName(question->qtype));
+ }
+ else if (question->flags & kDNSServiceFlagsThresholdFinder)
+ {
+ // always send one request with QU bit set when kDNSServiceFlagsThresholdFinder is set
+#if mDNS_REQUEST_UNICAST_RESPONSE
+ question->RequestUnicast = SET_QU_IN_FIRST_FOUR_QUERIES;
+#else // mDNS_REQUEST_UNICAST_RESPONSE
+ question->RequestUnicast = SET_QU_IN_FIRST_QUERY;
+#endif // mDNS_REQUEST_UNICAST_RESPONSE
+
+ LogInfo("InitCommonState: kDNSServiceFlagsThresholdFinder set, setting RequestUnicast = %d for %##s (%s)",
+ question->RequestUnicast, question->qname.c, DNSTypeName(question->qtype));
+ }
+#endif // APPLE_OSX_mDNSResponder
+
+ question->LastQTxTime = m->timenow;
+ question->CNAMEReferrals = 0;
+
+ question->WakeOnResolveCount = 0;
+ if (question->WakeOnResolve)
+ {
+ question->WakeOnResolveCount = InitialWakeOnResolveCount;
+ purge = mDNStrue;
+ }
+
+ for (i=0; i<DupSuppressInfoSize; i++)
+ question->DupSuppress[i].InterfaceID = mDNSNULL;
+
+ question->Restart = 0;
+
+ debugf("InitCommonState: Question %##s (%s) Interface %p Now %d Send in %d Answer in %d (%p) %s (%p)",
+ question->qname.c, DNSTypeName(question->qtype), question->InterfaceID, m->timenow,
+ NextQSendTime(question) - m->timenow,
+ question->DelayAnswering ? question->DelayAnswering - m->timenow : 0,
+ question, question->DuplicateOf ? "duplicate of" : "not duplicate", question->DuplicateOf);
+
+ if (question->DelayAnswering)
+ LogInfo("InitCommonState: Delaying answering for %d ticks while cache stabilizes for %##s (%s)",
+ question->DelayAnswering - m->timenow, question->qname.c, DNSTypeName(question->qtype));
+
+ return(purge);
+}
+
+// Excludes the DNS Config fields which are already handled by InitDNSConfig()
+mDNSlocal void InitWABState(DNSQuestion *const question)
+{
+ // We'll create our question->LocalSocket on demand, if needed.
+ // We won't need one for duplicate questions, or from questions answered immediately out of the cache.
+ // We also don't need one for LLQs because (when we're using NAT) we want them all to share a single
+ // NAT mapping for receiving inbound add/remove events.
+ question->LocalSocket = mDNSNULL;
+ question->unansweredQueries = 0;
+ question->nta = mDNSNULL;
+ question->servAddr = zeroAddr;
+ question->servPort = zeroIPPort;
+ question->tcp = mDNSNULL;
+ question->NoAnswer = NoAnswer_Normal;
+}
+
+mDNSlocal void InitLLQNATState(mDNS *const m)
+{
+ // If we don't have our NAT mapping active, start it now
+ if (!m->LLQNAT.clientCallback)
+ {
+ m->LLQNAT.Protocol = NATOp_MapUDP;
+ m->LLQNAT.IntPort = m->UnicastPort4;
+ m->LLQNAT.RequestedPort = m->UnicastPort4;
+ m->LLQNAT.clientCallback = LLQNATCallback;
+ m->LLQNAT.clientContext = (void*)1; // Means LLQ NAT Traversal just started
+ mDNS_StartNATOperation_internal(m, &m->LLQNAT);
+ }
+}
+
+mDNSlocal void InitLLQState(DNSQuestion *const question)
+{
+ question->state = LLQ_InitialRequest;
+ question->ReqLease = 0;
+ question->expire = 0;
+ question->ntries = 0;
+ question->id = zeroOpaque64;
+}
+
+// InitDNSSECProxyState() is called by mDNS_StartQuery_internal() to initialize
+// DNSSEC & DNS Proxy fields of the DNS Question.
+mDNSlocal void InitDNSSECProxyState(mDNS *const m, DNSQuestion *const question)
+{
+ (void) m;
+
+ // DNS server selection affects DNSSEC. Turn off validation if req_DO is not set
+ // or the request is going over cellular interface.
+ //
+ // Note: This needs to be done here before we call FindDuplicateQuestion as it looks
+ // at ValidationRequired setting also.
+ if (question->qDNSServer)
+ {
+ if (question->qDNSServer->cellIntf)
+ {
+ LogInfo("InitDNSSECProxyState: Turning off validation for %##s (%s); going over cell", question->qname.c, DNSTypeName(question->qtype));
+ question->ValidationRequired = mDNSfalse;
+ }
+ if (DNSSECOptionalQuestion(question) && !(question->qDNSServer->req_DO))
+ {
+ LogInfo("InitDNSSECProxyState: Turning off validation for %##s (%s); req_DO false",
+ question->qname.c, DNSTypeName(question->qtype));
+ question->ValidationRequired = DNSSEC_VALIDATION_NONE;
+ }
+ }
+ question->ValidationState = (question->ValidationRequired ? DNSSECValRequired : DNSSECValNotRequired);
+ question->ValidationStatus = 0;
+ question->responseFlags = zeroID;
+}
+
+// Once the question is completely initialized including the duplicate logic, this function
+// is called to finalize the unicast question which requires flushing the cache if needed,
+// activating the query etc.
+mDNSlocal void FinalizeUnicastQuestion(mDNS *const m, DNSQuestion *question, mDNSBool purge)
+{
+ // Ensure DNS related info of duplicate question is same as the orig question
+ if (question->DuplicateOf)
+ {
+ question->validDNSServers = question->DuplicateOf->validDNSServers;
+ question->qDNSServer = question->DuplicateOf->qDNSServer;
+ LogInfo("FinalizeUnicastQuestion: Duplicate question %p (%p) %##s (%s), DNS Server %#a:%d",
+ question, question->DuplicateOf, question->qname.c, DNSTypeName(question->qtype),
+ question->qDNSServer ? &question->qDNSServer->addr : mDNSNULL,
+ mDNSVal16(question->qDNSServer ? question->qDNSServer->port : zeroIPPort));
+ }
+
+ ActivateUnicastQuery(m, question, mDNSfalse);
+
+ // If purge was set above, flush the cache. Need to do this after we set the
+ // DNS server on the question
+ if (purge)
+ {
+ question->DelayAnswering = 0;
+ mDNS_PurgeForQuestion(m, question);
+ }
+ else if (!question->DuplicateOf && DNSSECQuestion(question))
+ {
+ // For DNSSEC questions, we need to have the RRSIGs also for verification.
+ CheckForDNSSECRecords(m, question);
+ }
+ if (question->LongLived)
+ {
+ // Unlike other initializations, InitLLQNATState should be done after
+ // we determine that it is a unicast question. LongLived is set for
+ // both multicast and unicast browse questions but we should initialize
+ // the LLQ NAT state only for unicast. Otherwise we will unnecessarily
+ // start the NAT traversal that is not needed.
+ InitLLQNATState(m);
#if APPLE_OSX_mDNSResponder
- if (question->LongLived)
- UpdateAutoTunnelDomainStatuses(m);
+ UpdateAutoTunnelDomainStatuses(m);
#endif
-
- }
- else
- {
- if (question->TimeoutQuestion)
- question->StopTime = NonZeroTime(m->timenow + GetTimeoutForMcastQuestion(m, question) * mDNSPlatformOneSecond);
- }
- if (question->StopTime) SetNextQueryStopTime(m, question);
- SetNextQueryTime(m,question);
- }
-
- return(mStatus_NoError);
- }
- }
+ }
+}
+
+mDNSexport mStatus mDNS_StartQuery_internal(mDNS *const m, DNSQuestion *const question)
+{
+ DNSQuestion **q;
+ mStatus vStatus;
+ mDNSBool purge;
+
+ // First check for cache space (can't do queries if there is no cache space allocated)
+ if (m->rrcache_size == 0)
+ return(mStatus_NoCache);
+
+ vStatus = ValidateParameters(m, question);
+ if (vStatus)
+ return(vStatus);
+
+ question->TargetQID =
+#ifndef UNICAST_DISABLED
+ (question->Target.type || Question_uDNS(question)) ? mDNS_NewMessageID(m) :
+#endif // UNICAST_DISABLED
+ zeroID;
+ debugf("mDNS_StartQuery_internal: %##s (%s)", question->qname.c, DNSTypeName(question->qtype));
+
+ // Note: It important that new questions are appended at the *end* of the list, not prepended at the start
+ q = &m->Questions;
+ if (question->InterfaceID == mDNSInterface_LocalOnly || question->InterfaceID == mDNSInterface_P2P)
+ q = &m->LocalOnlyQuestions;
+ while (*q && *q != question)
+ q=&(*q)->next;
+
+ if (*q)
+ {
+ LogMsg("mDNS_StartQuery_internal: Error! Tried to add a question %##s (%s) %p that's already in the active list",
+ question->qname.c, DNSTypeName(question->qtype), question);
+ return(mStatus_AlreadyRegistered);
+ }
+ *q = question;
+
+
+ // Intialize the question. The only ordering constraint we have today is that
+ // InitDNSSECProxyState should be called after the DNS server is selected (in
+ // InitCommonState -> InitDNSConfig) as DNS server selection affects DNSSEC
+ // validation.
+
+ purge = InitCommonState(m, question);
+ InitWABState(question);
+ InitLLQState(question);
+ InitDNSSECProxyState(m, question);
+
+ // FindDuplicateQuestion should be called last after all the intialization
+ // as the duplicate logic could be potentially based on any field in the
+ // question.
+ question->DuplicateOf = FindDuplicateQuestion(m, question);
+ if (question->DuplicateOf)
+ question->AuthInfo = question->DuplicateOf->AuthInfo;
+
+ if (question->InterfaceID == mDNSInterface_LocalOnly || question->InterfaceID == mDNSInterface_P2P)
+ {
+ if (!m->NewLocalOnlyQuestions)
+ m->NewLocalOnlyQuestions = question;
+ }
+ else
+ {
+ if (!m->NewQuestions)
+ m->NewQuestions = question;
+
+ // If the question's id is non-zero, then it's Wide Area
+ // MUST NOT do this Wide Area setup until near the end of
+ // mDNS_StartQuery_internal -- this code may itself issue queries (e.g. SOA,
+ // NS, etc.) and if we haven't finished setting up our own question and setting
+ // m->NewQuestions if necessary then we could end up recursively re-entering
+ // this routine with the question list data structures in an inconsistent state.
+ if (!mDNSOpaque16IsZero(question->TargetQID))
+ {
+ FinalizeUnicastQuestion(m, question, purge);
+ }
+ else
+ {
+ if (purge)
+ {
+ LogInfo("mDNS_StartQuery_internal: Purging for %##s", question->qname.c);
+ mDNS_PurgeForQuestion(m, question);
+ }
+ }
+ }
+
+ return(mStatus_NoError);
+}
// CancelGetZoneData is an internal routine (i.e. must be called with the lock already held)
mDNSexport void CancelGetZoneData(mDNS *const m, ZoneData *nta)
- {
- debugf("CancelGetZoneData %##s (%s)", nta->question.qname.c, DNSTypeName(nta->question.qtype));
- // This function may be called anytime to free the zone information.The question may or may not have stopped.
- // If it was already stopped, mDNS_StopQuery_internal would have set q->ThisQInterval to -1 and should not
- // call it again
- if (nta->question.ThisQInterval != -1)
- {
- mDNS_StopQuery_internal(m, &nta->question);
- if (nta->question.ThisQInterval != -1)
- LogMsg("CancelGetZoneData: Question %##s (%s) ThisQInterval %d not -1", nta->question.qname.c, DNSTypeName(nta->question.qtype), nta->question.ThisQInterval);
- }
- mDNSPlatformMemFree(nta);
- }
+{
+ debugf("CancelGetZoneData %##s (%s)", nta->question.qname.c, DNSTypeName(nta->question.qtype));
+ // This function may be called anytime to free the zone information.The question may or may not have stopped.
+ // If it was already stopped, mDNS_StopQuery_internal would have set q->ThisQInterval to -1 and should not
+ // call it again
+ if (nta->question.ThisQInterval != -1)
+ {
+ mDNS_StopQuery_internal(m, &nta->question);
+ if (nta->question.ThisQInterval != -1)
+ LogMsg("CancelGetZoneData: Question %##s (%s) ThisQInterval %d not -1", nta->question.qname.c, DNSTypeName(nta->question.qtype), nta->question.ThisQInterval);
+ }
+ mDNSPlatformMemFree(nta);
+}
mDNSexport mStatus mDNS_StopQuery_internal(mDNS *const m, DNSQuestion *const question)
- {
- const mDNSu32 slot = HashSlot(&question->qname);
- CacheGroup *cg = CacheGroupForName(m, slot, question->qnamehash, &question->qname);
- CacheRecord *rr;
- DNSQuestion **qp = &m->Questions;
-
- //LogInfo("mDNS_StopQuery_internal %##s (%s)", question->qname.c, DNSTypeName(question->qtype));
-
- if (question->InterfaceID == mDNSInterface_LocalOnly || question->InterfaceID == mDNSInterface_P2P) qp = &m->LocalOnlyQuestions;
- while (*qp && *qp != question) qp=&(*qp)->next;
- if (*qp) *qp = (*qp)->next;
- else
- {
+{
+ const mDNSu32 slot = HashSlot(&question->qname);
+ CacheGroup *cg = CacheGroupForName(m, slot, question->qnamehash, &question->qname);
+ CacheRecord *rr;
+ DNSQuestion **qp = &m->Questions;
+
+ //LogInfo("mDNS_StopQuery_internal %##s (%s)", question->qname.c, DNSTypeName(question->qtype));
+
+ if (question->InterfaceID == mDNSInterface_LocalOnly || question->InterfaceID == mDNSInterface_P2P) qp = &m->LocalOnlyQuestions;
+ while (*qp && *qp != question) qp=&(*qp)->next;
+ if (*qp) *qp = (*qp)->next;
+ else
+ {
#if !ForceAlerts
- if (question->ThisQInterval >= 0) // Only log error message if the query was supposed to be active
+ if (question->ThisQInterval >= 0) // Only log error message if the query was supposed to be active
#endif
- LogMsg("mDNS_StopQuery_internal: Question %##s (%s) not found in active list",
- question->qname.c, DNSTypeName(question->qtype));
+ LogMsg("mDNS_StopQuery_internal: Question %##s (%s) not found in active list",
+ question->qname.c, DNSTypeName(question->qtype));
#if ForceAlerts
- *(long*)0 = 0;
+ *(long*)0 = 0;
#endif
- return(mStatus_BadReferenceErr);
- }
-
- // Take care to cut question from list *before* calling UpdateQuestionDuplicates
- UpdateQuestionDuplicates(m, question);
- // But don't trash ThisQInterval until afterwards.
- question->ThisQInterval = -1;
-
- // If there are any cache records referencing this as their active question, then see if there is any
- // other question that is also referencing them, else their CRActiveQuestion needs to get set to NULL.
- for (rr = cg ? cg->members : mDNSNULL; rr; rr=rr->next)
- {
- if (rr->CRActiveQuestion == question)
- {
- DNSQuestion *q;
- // Checking for ActiveQuestion filters questions that are suppressed also
- // as suppressed questions are not active
- for (q = m->Questions; q; q=q->next) // Scan our list of questions
- if (ActiveQuestion(q) && ResourceRecordAnswersQuestion(&rr->resrec, q))
- break;
- if (q)
- debugf("mDNS_StopQuery_internal: Updating CRActiveQuestion to %p for cache record %s, Original question CurrentAnswers %d, new question "
- "CurrentAnswers %d, SuppressQuery %d", q, CRDisplayString(m,rr), question->CurrentAnswers, q->CurrentAnswers, q->SuppressQuery);
- rr->CRActiveQuestion = q; // Question used to be active; new value may or may not be null
- if (!q) m->rrcache_active--; // If no longer active, decrement rrcache_active count
- }
- }
-
- // If we just deleted the question that CacheRecordAdd() or CacheRecordRmv() is about to look at,
- // bump its pointer forward one question.
- if (m->CurrentQuestion == question)
- {
- debugf("mDNS_StopQuery_internal: Just deleted the currently active question: %##s (%s)",
- question->qname.c, DNSTypeName(question->qtype));
- m->CurrentQuestion = question->next;
- }
-
- if (m->NewQuestions == question)
- {
- debugf("mDNS_StopQuery_internal: Just deleted a new question that wasn't even answered yet: %##s (%s)",
- question->qname.c, DNSTypeName(question->qtype));
- m->NewQuestions = question->next;
- }
-
- if (m->NewLocalOnlyQuestions == question) m->NewLocalOnlyQuestions = question->next;
-
- if (m->RestartQuestion == question)
- {
- LogMsg("mDNS_StopQuery_internal: Just deleted the current restart question: %##s (%s)",
- question->qname.c, DNSTypeName(question->qtype));
- m->RestartQuestion = question->next;
- }
-
- // Take care not to trash question->next until *after* we've updated m->CurrentQuestion and m->NewQuestions
- question->next = mDNSNULL;
-
- // LogMsg("mDNS_StopQuery_internal: Question %##s (%s) removed", question->qname.c, DNSTypeName(question->qtype));
-
- // And finally, cancel any associated GetZoneData operation that's still running.
- // Must not do this until last, because there's a good chance the GetZoneData question is the next in the list,
- // so if we delete it earlier in this routine, we could find that our "question->next" pointer above is already
- // invalid before we even use it. By making sure that we update m->CurrentQuestion and m->NewQuestions if necessary
- // *first*, then they're all ready to be updated a second time if necessary when we cancel our GetZoneData query.
- if (question->tcp) { DisposeTCPConn(question->tcp); question->tcp = mDNSNULL; }
- if (question->LocalSocket) { mDNSPlatformUDPClose(question->LocalSocket); question->LocalSocket = mDNSNULL; }
- if (!mDNSOpaque16IsZero(question->TargetQID) && question->LongLived)
- {
- // Scan our list to see if any more wide-area LLQs remain. If not, stop our NAT Traversal.
- DNSQuestion *q;
- for (q = m->Questions; q; q=q->next)
- if (!mDNSOpaque16IsZero(q->TargetQID) && q->LongLived) break;
- if (!q)
- {
- if (!m->LLQNAT.clientContext) // Should never happen, but just in case...
- LogMsg("mDNS_StopQuery ERROR LLQNAT.clientContext NULL");
- else
- {
- LogInfo("Stopping LLQNAT");
- mDNS_StopNATOperation_internal(m, &m->LLQNAT);
- m->LLQNAT.clientContext = mDNSNULL; // Means LLQ NAT Traversal not running
- }
- }
-
- // If necessary, tell server it can delete this LLQ state
- if (question->state == LLQ_Established)
- {
- question->ReqLease = 0;
- sendLLQRefresh(m, question);
- // If we need need to make a TCP connection to cancel the LLQ, that's going to take a little while.
- // We clear the tcp->question backpointer so that when the TCP connection completes, it doesn't
- // crash trying to access our cancelled question, but we don't cancel the TCP operation itself --
- // we let that run out its natural course and complete asynchronously.
- if (question->tcp)
- {
- question->tcp->question = mDNSNULL;
- question->tcp = mDNSNULL;
- }
- }
+ return(mStatus_BadReferenceErr);
+ }
+
+ // Take care to cut question from list *before* calling UpdateQuestionDuplicates
+ UpdateQuestionDuplicates(m, question);
+ // But don't trash ThisQInterval until afterwards.
+ question->ThisQInterval = -1;
+
+ // If there are any cache records referencing this as their active question, then see if there is any
+ // other question that is also referencing them, else their CRActiveQuestion needs to get set to NULL.
+ for (rr = cg ? cg->members : mDNSNULL; rr; rr=rr->next)
+ {
+ if (rr->CRActiveQuestion == question)
+ {
+ DNSQuestion *q;
+ // Checking for ActiveQuestion filters questions that are suppressed also
+ // as suppressed questions are not active
+ for (q = m->Questions; q; q=q->next) // Scan our list of questions
+ if (ActiveQuestion(q) && ResourceRecordAnswersQuestion(&rr->resrec, q))
+ break;
+ if (q)
+ debugf("mDNS_StopQuery_internal: Updating CRActiveQuestion to %p for cache record %s, Original question CurrentAnswers %d, new question "
+ "CurrentAnswers %d, SuppressQuery %d", q, CRDisplayString(m,rr), question->CurrentAnswers, q->CurrentAnswers, q->SuppressQuery);
+ rr->CRActiveQuestion = q; // Question used to be active; new value may or may not be null
+ if (!q) m->rrcache_active--; // If no longer active, decrement rrcache_active count
+ }
+ }
+
+ // If we just deleted the question that CacheRecordAdd() or CacheRecordRmv() is about to look at,
+ // bump its pointer forward one question.
+ if (m->CurrentQuestion == question)
+ {
+ debugf("mDNS_StopQuery_internal: Just deleted the currently active question: %##s (%s)",
+ question->qname.c, DNSTypeName(question->qtype));
+ m->CurrentQuestion = question->next;
+ }
+
+ if (m->NewQuestions == question)
+ {
+ debugf("mDNS_StopQuery_internal: Just deleted a new question that wasn't even answered yet: %##s (%s)",
+ question->qname.c, DNSTypeName(question->qtype));
+ m->NewQuestions = question->next;
+ }
+
+ if (m->NewLocalOnlyQuestions == question) m->NewLocalOnlyQuestions = question->next;
+
+ if (m->RestartQuestion == question)
+ {
+ LogMsg("mDNS_StopQuery_internal: Just deleted the current restart question: %##s (%s)",
+ question->qname.c, DNSTypeName(question->qtype));
+ m->RestartQuestion = question->next;
+ }
+
+ if (m->ValidationQuestion == question)
+ {
+ LogInfo("mDNS_StopQuery_internal: Just deleted the current Validation question: %##s (%s)",
+ question->qname.c, DNSTypeName(question->qtype));
+ m->ValidationQuestion = question->next;
+ }
+
+ // Take care not to trash question->next until *after* we've updated m->CurrentQuestion and m->NewQuestions
+ question->next = mDNSNULL;
+
+ // LogMsg("mDNS_StopQuery_internal: Question %##s (%s) removed", question->qname.c, DNSTypeName(question->qtype));
+
+ // And finally, cancel any associated GetZoneData operation that's still running.
+ // Must not do this until last, because there's a good chance the GetZoneData question is the next in the list,
+ // so if we delete it earlier in this routine, we could find that our "question->next" pointer above is already
+ // invalid before we even use it. By making sure that we update m->CurrentQuestion and m->NewQuestions if necessary
+ // *first*, then they're all ready to be updated a second time if necessary when we cancel our GetZoneData query.
+ if (question->tcp) { DisposeTCPConn(question->tcp); question->tcp = mDNSNULL; }
+ if (question->LocalSocket) { mDNSPlatformUDPClose(question->LocalSocket); question->LocalSocket = mDNSNULL; }
+ if (!mDNSOpaque16IsZero(question->TargetQID) && question->LongLived)
+ {
+ // Scan our list to see if any more wide-area LLQs remain. If not, stop our NAT Traversal.
+ DNSQuestion *q;
+ for (q = m->Questions; q; q=q->next)
+ if (!mDNSOpaque16IsZero(q->TargetQID) && q->LongLived) break;
+ if (!q)
+ {
+ if (!m->LLQNAT.clientCallback) // Should never happen, but just in case...
+ {
+ LogMsg("mDNS_StopQuery ERROR LLQNAT.clientCallback NULL");
+ }
+ else
+ {
+ LogInfo("Stopping LLQNAT");
+ mDNS_StopNATOperation_internal(m, &m->LLQNAT);
+ m->LLQNAT.clientCallback = mDNSNULL; // Means LLQ NAT Traversal not running
+ }
+ }
+
+ // If necessary, tell server it can delete this LLQ state
+ if (question->state == LLQ_Established)
+ {
+ question->ReqLease = 0;
+ sendLLQRefresh(m, question);
+ // If we need need to make a TCP connection to cancel the LLQ, that's going to take a little while.
+ // We clear the tcp->question backpointer so that when the TCP connection completes, it doesn't
+ // crash trying to access our cancelled question, but we don't cancel the TCP operation itself --
+ // we let that run out its natural course and complete asynchronously.
+ if (question->tcp)
+ {
+ question->tcp->question = mDNSNULL;
+ question->tcp = mDNSNULL;
+ }
+ }
#if APPLE_OSX_mDNSResponder
- UpdateAutoTunnelDomainStatuses(m);
+ UpdateAutoTunnelDomainStatuses(m);
#endif
- }
- // wait until we send the refresh above which needs the nta
- if (question->nta) { CancelGetZoneData(m, question->nta); question->nta = mDNSNULL; }
+ }
+ // wait until we send the refresh above which needs the nta
+ if (question->nta) { CancelGetZoneData(m, question->nta); question->nta = mDNSNULL; }
- return(mStatus_NoError);
- }
+ if (question->ValidationRequired && question->DNSSECAuthInfo)
+ {
+ LogInfo("mDNS_StopQuery_internal: freeing DNSSECAuthInfo %##s", question->qname.c);
+ question->DAIFreeCallback(m, question->DNSSECAuthInfo);
+ question->DNSSECAuthInfo = mDNSNULL;
+ }
+ if (question->AnonInfo)
+ {
+ FreeAnonInfo(question->AnonInfo);
+ question->AnonInfo = mDNSNULL;
+ }
+
+ return(mStatus_NoError);
+}
mDNSexport mStatus mDNS_StartQuery(mDNS *const m, DNSQuestion *const question)
- {
- mStatus status;
- mDNS_Lock(m);
- status = mDNS_StartQuery_internal(m, question);
- mDNS_Unlock(m);
- return(status);
- }
+{
+ mStatus status;
+ mDNS_Lock(m);
+ status = mDNS_StartQuery_internal(m, question);
+ mDNS_Unlock(m);
+ return(status);
+}
mDNSexport mStatus mDNS_StopQuery(mDNS *const m, DNSQuestion *const question)
- {
- mStatus status;
- mDNS_Lock(m);
- status = mDNS_StopQuery_internal(m, question);
- mDNS_Unlock(m);
- return(status);
- }
+{
+ mStatus status;
+ mDNS_Lock(m);
+ status = mDNS_StopQuery_internal(m, question);
+ mDNS_Unlock(m);
+ return(status);
+}
// Note that mDNS_StopQueryWithRemoves() does not currently implement the full generality of the other APIs
// Specifically, question callbacks invoked as a result of this call cannot themselves make API calls.
// We invoke the callback without using mDNS_DropLockBeforeCallback/mDNS_ReclaimLockAfterCallback
// specifically to catch and report if the client callback does try to make API calls
mDNSexport mStatus mDNS_StopQueryWithRemoves(mDNS *const m, DNSQuestion *const question)
- {
- mStatus status;
- DNSQuestion *qq;
- mDNS_Lock(m);
-
- // Check if question is new -- don't want to give remove events for a question we haven't even answered yet
- for (qq = m->NewQuestions; qq; qq=qq->next) if (qq == question) break;
-
- status = mDNS_StopQuery_internal(m, question);
- if (status == mStatus_NoError && !qq)
- {
- const CacheRecord *rr;
- const mDNSu32 slot = HashSlot(&question->qname);
- CacheGroup *const cg = CacheGroupForName(m, slot, question->qnamehash, &question->qname);
- LogInfo("Generating terminal removes for %##s (%s)", question->qname.c, DNSTypeName(question->qtype));
- for (rr = cg ? cg->members : mDNSNULL; rr; rr=rr->next)
- if (rr->resrec.RecordType != kDNSRecordTypePacketNegative && SameNameRecordAnswersQuestion(&rr->resrec, question))
- {
- // Don't use mDNS_DropLockBeforeCallback() here, since we don't allow API calls
- if (question->QuestionCallback)
- question->QuestionCallback(m, question, &rr->resrec, mDNSfalse);
- }
- }
- mDNS_Unlock(m);
- return(status);
- }
+{
+ mStatus status;
+ DNSQuestion *qq;
+ mDNS_Lock(m);
+
+ // Check if question is new -- don't want to give remove events for a question we haven't even answered yet
+ for (qq = m->NewQuestions; qq; qq=qq->next) if (qq == question) break;
+
+ status = mDNS_StopQuery_internal(m, question);
+ if (status == mStatus_NoError && !qq)
+ {
+ const CacheRecord *rr;
+ const mDNSu32 slot = HashSlot(&question->qname);
+ CacheGroup *const cg = CacheGroupForName(m, slot, question->qnamehash, &question->qname);
+ LogInfo("Generating terminal removes for %##s (%s)", question->qname.c, DNSTypeName(question->qtype));
+ for (rr = cg ? cg->members : mDNSNULL; rr; rr=rr->next)
+ if (rr->resrec.RecordType != kDNSRecordTypePacketNegative && SameNameRecordAnswersQuestion(&rr->resrec, question))
+ {
+ // Don't use mDNS_DropLockBeforeCallback() here, since we don't allow API calls
+ if (question->QuestionCallback)
+ question->QuestionCallback(m, question, &rr->resrec, mDNSfalse);
+ }
+ }
+ mDNS_Unlock(m);
+ return(status);
+}
mDNSexport mStatus mDNS_Reconfirm(mDNS *const m, CacheRecord *const cr)
- {
- mStatus status;
- mDNS_Lock(m);
- status = mDNS_Reconfirm_internal(m, cr, kDefaultReconfirmTimeForNoAnswer);
- if (status == mStatus_NoError) ReconfirmAntecedents(m, cr->resrec.name, cr->resrec.namehash, 0);
- mDNS_Unlock(m);
- return(status);
- }
+{
+ mStatus status;
+ mDNS_Lock(m);
+ status = mDNS_Reconfirm_internal(m, cr, kDefaultReconfirmTimeForNoAnswer);
+ if (status == mStatus_NoError) ReconfirmAntecedents(m, cr->resrec.name, cr->resrec.namehash, 0);
+ mDNS_Unlock(m);
+ return(status);
+}
mDNSexport mStatus mDNS_ReconfirmByValue(mDNS *const m, ResourceRecord *const rr)
- {
- mStatus status = mStatus_BadReferenceErr;
- CacheRecord *cr;
- mDNS_Lock(m);
- cr = FindIdenticalRecordInCache(m, rr);
- debugf("mDNS_ReconfirmByValue: %p %s", cr, RRDisplayString(m, rr));
- if (cr) status = mDNS_Reconfirm_internal(m, cr, kDefaultReconfirmTimeForNoAnswer);
- if (status == mStatus_NoError) ReconfirmAntecedents(m, cr->resrec.name, cr->resrec.namehash, 0);
- mDNS_Unlock(m);
- return(status);
- }
+{
+ mStatus status = mStatus_BadReferenceErr;
+ CacheRecord *cr;
+ mDNS_Lock(m);
+ cr = FindIdenticalRecordInCache(m, rr);
+ debugf("mDNS_ReconfirmByValue: %p %s", cr, RRDisplayString(m, rr));
+ if (cr) status = mDNS_Reconfirm_internal(m, cr, kDefaultReconfirmTimeForNoAnswer);
+ if (status == mStatus_NoError) ReconfirmAntecedents(m, cr->resrec.name, cr->resrec.namehash, 0);
+ mDNS_Unlock(m);
+ return(status);
+}
mDNSlocal mStatus mDNS_StartBrowse_internal(mDNS *const m, DNSQuestion *const question,
- const domainname *const srv, const domainname *const domain,
- const mDNSInterfaceID InterfaceID, mDNSBool ForceMCast, mDNSQuestionCallback *Callback, void *Context)
- {
- question->InterfaceID = InterfaceID;
- question->Target = zeroAddr;
- question->qtype = kDNSType_PTR;
- question->qclass = kDNSClass_IN;
- question->LongLived = mDNStrue;
- question->ExpectUnique = mDNSfalse;
- question->ForceMCast = ForceMCast;
- question->ReturnIntermed = mDNSfalse;
- question->SuppressUnusable = mDNSfalse;
- question->SearchListIndex = 0;
- question->AppendSearchDomains = 0;
- question->RetryWithSearchDomains = mDNSfalse;
- question->TimeoutQuestion = 0;
- question->WakeOnResolve = 0;
- question->qnameOrig = mDNSNULL;
- question->QuestionCallback = Callback;
- question->QuestionContext = Context;
- if (!ConstructServiceName(&question->qname, mDNSNULL, srv, domain)) return(mStatus_BadParamErr);
-
- return(mDNS_StartQuery_internal(m, question));
- }
+ const domainname *const srv, const domainname *const domain,
+ const mDNSu8 *anondata, const mDNSInterfaceID InterfaceID, mDNSu32 flags,
+ mDNSBool ForceMCast, mDNSBool useBackgroundTrafficClass,
+ mDNSQuestionCallback *Callback, void *Context)
+{
+ question->InterfaceID = InterfaceID;
+ question->flags = flags;
+ question->Target = zeroAddr;
+ question->qtype = kDNSType_PTR;
+ question->qclass = kDNSClass_IN;
+ question->LongLived = mDNStrue;
+ question->ExpectUnique = mDNSfalse;
+ question->ForceMCast = ForceMCast;
+ question->ReturnIntermed = mDNSfalse;
+ question->SuppressUnusable = mDNSfalse;
+ question->DenyOnCellInterface = mDNSfalse;
+ question->DenyOnExpInterface = mDNSfalse;
+ question->SearchListIndex = 0;
+ question->AppendSearchDomains = 0;
+ question->RetryWithSearchDomains = mDNSfalse;
+ question->TimeoutQuestion = 0;
+ question->WakeOnResolve = 0;
+ question->UseBackgroundTrafficClass = useBackgroundTrafficClass;
+ question->ValidationRequired = 0;
+ question->ValidatingResponse = 0;
+ question->ProxyQuestion = 0;
+ question->qnameOrig = mDNSNULL;
+ question->AnonInfo = mDNSNULL;
+ question->QuestionCallback = Callback;
+ question->QuestionContext = Context;
+
+ if (!ConstructServiceName(&question->qname, mDNSNULL, srv, domain))
+ return(mStatus_BadParamErr);
+
+ if (anondata)
+ {
+ question->AnonInfo = AllocateAnonInfo(&question->qname, anondata, mDNSPlatformStrLen(anondata), mDNSNULL);
+ if (!question->AnonInfo)
+ return(mStatus_BadParamErr);
+ }
+
+ return(mDNS_StartQuery_internal(m, question));
+}
mDNSexport mStatus mDNS_StartBrowse(mDNS *const m, DNSQuestion *const question,
- const domainname *const srv, const domainname *const domain,
- const mDNSInterfaceID InterfaceID, mDNSBool ForceMCast, mDNSQuestionCallback *Callback, void *Context)
- {
- mStatus status;
- mDNS_Lock(m);
- status = mDNS_StartBrowse_internal(m, question, srv, domain, InterfaceID, ForceMCast, Callback, Context);
- mDNS_Unlock(m);
- return(status);
- }
+ const domainname *const srv, const domainname *const domain,
+ const mDNSu8 *anondata, const mDNSInterfaceID InterfaceID, mDNSu32 flags,
+ mDNSBool ForceMCast, mDNSBool useBackgroundTrafficClass,
+ mDNSQuestionCallback *Callback, void *Context)
+{
+ mStatus status;
+ mDNS_Lock(m);
+ status = mDNS_StartBrowse_internal(m, question, srv, domain, anondata, InterfaceID, flags, ForceMCast, useBackgroundTrafficClass, Callback, Context);
+ mDNS_Unlock(m);
+ return(status);
+}
mDNSlocal mDNSBool MachineHasActiveIPv6(mDNS *const m)
- {
- NetworkInterfaceInfo *intf;
- for (intf = m->HostInterfaces; intf; intf = intf->next)
- if (intf->ip.type == mDNSAddrType_IPv6) return(mDNStrue);
- return(mDNSfalse);
- }
+{
+ NetworkInterfaceInfo *intf;
+ for (intf = m->HostInterfaces; intf; intf = intf->next)
+ if (intf->ip.type == mDNSAddrType_IPv6) return(mDNStrue);
+ return(mDNSfalse);
+}
mDNSlocal void FoundServiceInfoSRV(mDNS *const m, DNSQuestion *question, const ResourceRecord *const answer, QC_result AddRecord)
- {
- ServiceInfoQuery *query = (ServiceInfoQuery *)question->QuestionContext;
- mDNSBool PortChanged = !mDNSSameIPPort(query->info->port, answer->rdata->u.srv.port);
- if (!AddRecord) return;
- if (answer->rrtype != kDNSType_SRV) return;
-
- query->info->port = answer->rdata->u.srv.port;
-
- // If this is our first answer, then set the GotSRV flag and start the address query
- if (!query->GotSRV)
- {
- query->GotSRV = mDNStrue;
- query->qAv4.InterfaceID = answer->InterfaceID;
- AssignDomainName(&query->qAv4.qname, &answer->rdata->u.srv.target);
- query->qAv6.InterfaceID = answer->InterfaceID;
- AssignDomainName(&query->qAv6.qname, &answer->rdata->u.srv.target);
- mDNS_StartQuery(m, &query->qAv4);
- // Only do the AAAA query if this machine actually has IPv6 active
- if (MachineHasActiveIPv6(m)) mDNS_StartQuery(m, &query->qAv6);
- }
- // If this is not our first answer, only re-issue the address query if the target host name has changed
- else if ((query->qAv4.InterfaceID != query->qSRV.InterfaceID && query->qAv4.InterfaceID != answer->InterfaceID) ||
- !SameDomainName(&query->qAv4.qname, &answer->rdata->u.srv.target))
- {
- mDNS_StopQuery(m, &query->qAv4);
- if (query->qAv6.ThisQInterval >= 0) mDNS_StopQuery(m, &query->qAv6);
- if (SameDomainName(&query->qAv4.qname, &answer->rdata->u.srv.target) && !PortChanged)
- {
- // If we get here, it means:
- // 1. This is not our first SRV answer
- // 2. The interface ID is different, but the target host and port are the same
- // This implies that we're seeing the exact same SRV record on more than one interface, so we should
- // make our address queries at least as broad as the original SRV query so that we catch all the answers.
- query->qAv4.InterfaceID = query->qSRV.InterfaceID; // Will be mDNSInterface_Any, or a specific interface
- query->qAv6.InterfaceID = query->qSRV.InterfaceID;
- }
- else
- {
- query->qAv4.InterfaceID = answer->InterfaceID;
- AssignDomainName(&query->qAv4.qname, &answer->rdata->u.srv.target);
- query->qAv6.InterfaceID = answer->InterfaceID;
- AssignDomainName(&query->qAv6.qname, &answer->rdata->u.srv.target);
- }
- debugf("FoundServiceInfoSRV: Restarting address queries for %##s (%s)", query->qAv4.qname.c, DNSTypeName(query->qAv4.qtype));
- mDNS_StartQuery(m, &query->qAv4);
- // Only do the AAAA query if this machine actually has IPv6 active
- if (MachineHasActiveIPv6(m)) mDNS_StartQuery(m, &query->qAv6);
- }
- else if (query->ServiceInfoQueryCallback && query->GotADD && query->GotTXT && PortChanged)
- {
- if (++query->Answers >= 100)
- debugf("**** WARNING **** Have given %lu answers for %##s (SRV) %##s %u",
- query->Answers, query->qSRV.qname.c, answer->rdata->u.srv.target.c,
- mDNSVal16(answer->rdata->u.srv.port));
- query->ServiceInfoQueryCallback(m, query);
- }
- // CAUTION: MUST NOT do anything more with query after calling query->Callback(), because the client's
- // callback function is allowed to do anything, including deleting this query and freeing its memory.
- }
+{
+ ServiceInfoQuery *query = (ServiceInfoQuery *)question->QuestionContext;
+ mDNSBool PortChanged = !mDNSSameIPPort(query->info->port, answer->rdata->u.srv.port);
+ if (!AddRecord) return;
+ if (answer->rrtype != kDNSType_SRV) return;
+
+ query->info->port = answer->rdata->u.srv.port;
+
+ // If this is our first answer, then set the GotSRV flag and start the address query
+ if (!query->GotSRV)
+ {
+ query->GotSRV = mDNStrue;
+ query->qAv4.InterfaceID = answer->InterfaceID;
+ AssignDomainName(&query->qAv4.qname, &answer->rdata->u.srv.target);
+ query->qAv6.InterfaceID = answer->InterfaceID;
+ AssignDomainName(&query->qAv6.qname, &answer->rdata->u.srv.target);
+ mDNS_StartQuery(m, &query->qAv4);
+ // Only do the AAAA query if this machine actually has IPv6 active
+ if (MachineHasActiveIPv6(m)) mDNS_StartQuery(m, &query->qAv6);
+ }
+ // If this is not our first answer, only re-issue the address query if the target host name has changed
+ else if ((query->qAv4.InterfaceID != query->qSRV.InterfaceID && query->qAv4.InterfaceID != answer->InterfaceID) ||
+ !SameDomainName(&query->qAv4.qname, &answer->rdata->u.srv.target))
+ {
+ mDNS_StopQuery(m, &query->qAv4);
+ if (query->qAv6.ThisQInterval >= 0) mDNS_StopQuery(m, &query->qAv6);
+ if (SameDomainName(&query->qAv4.qname, &answer->rdata->u.srv.target) && !PortChanged)
+ {
+ // If we get here, it means:
+ // 1. This is not our first SRV answer
+ // 2. The interface ID is different, but the target host and port are the same
+ // This implies that we're seeing the exact same SRV record on more than one interface, so we should
+ // make our address queries at least as broad as the original SRV query so that we catch all the answers.
+ query->qAv4.InterfaceID = query->qSRV.InterfaceID; // Will be mDNSInterface_Any, or a specific interface
+ query->qAv6.InterfaceID = query->qSRV.InterfaceID;
+ }
+ else
+ {
+ query->qAv4.InterfaceID = answer->InterfaceID;
+ AssignDomainName(&query->qAv4.qname, &answer->rdata->u.srv.target);
+ query->qAv6.InterfaceID = answer->InterfaceID;
+ AssignDomainName(&query->qAv6.qname, &answer->rdata->u.srv.target);
+ }
+ debugf("FoundServiceInfoSRV: Restarting address queries for %##s (%s)", query->qAv4.qname.c, DNSTypeName(query->qAv4.qtype));
+ mDNS_StartQuery(m, &query->qAv4);
+ // Only do the AAAA query if this machine actually has IPv6 active
+ if (MachineHasActiveIPv6(m)) mDNS_StartQuery(m, &query->qAv6);
+ }
+ else if (query->ServiceInfoQueryCallback && query->GotADD && query->GotTXT && PortChanged)
+ {
+ if (++query->Answers >= 100)
+ debugf("**** WARNING **** Have given %lu answers for %##s (SRV) %##s %u",
+ query->Answers, query->qSRV.qname.c, answer->rdata->u.srv.target.c,
+ mDNSVal16(answer->rdata->u.srv.port));
+ query->ServiceInfoQueryCallback(m, query);
+ }
+ // CAUTION: MUST NOT do anything more with query after calling query->Callback(), because the client's
+ // callback function is allowed to do anything, including deleting this query and freeing its memory.
+}
mDNSlocal void FoundServiceInfoTXT(mDNS *const m, DNSQuestion *question, const ResourceRecord *const answer, QC_result AddRecord)
- {
- ServiceInfoQuery *query = (ServiceInfoQuery *)question->QuestionContext;
- if (!AddRecord) return;
- if (answer->rrtype != kDNSType_TXT) return;
- if (answer->rdlength > sizeof(query->info->TXTinfo)) return;
-
- query->GotTXT = mDNStrue;
- query->info->TXTlen = answer->rdlength;
- query->info->TXTinfo[0] = 0; // In case answer->rdlength is zero
- mDNSPlatformMemCopy(query->info->TXTinfo, answer->rdata->u.txt.c, answer->rdlength);
-
- verbosedebugf("FoundServiceInfoTXT: %##s GotADD=%d", query->info->name.c, query->GotADD);
-
- // CAUTION: MUST NOT do anything more with query after calling query->Callback(), because the client's
- // callback function is allowed to do anything, including deleting this query and freeing its memory.
- if (query->ServiceInfoQueryCallback && query->GotADD)
- {
- if (++query->Answers >= 100)
- debugf("**** WARNING **** have given %lu answers for %##s (TXT) %#s...",
- query->Answers, query->qSRV.qname.c, answer->rdata->u.txt.c);
- query->ServiceInfoQueryCallback(m, query);
- }
- }
+{
+ ServiceInfoQuery *query = (ServiceInfoQuery *)question->QuestionContext;
+ if (!AddRecord) return;
+ if (answer->rrtype != kDNSType_TXT) return;
+ if (answer->rdlength > sizeof(query->info->TXTinfo)) return;
+
+ query->GotTXT = mDNStrue;
+ query->info->TXTlen = answer->rdlength;
+ query->info->TXTinfo[0] = 0; // In case answer->rdlength is zero
+ mDNSPlatformMemCopy(query->info->TXTinfo, answer->rdata->u.txt.c, answer->rdlength);
+
+ verbosedebugf("FoundServiceInfoTXT: %##s GotADD=%d", query->info->name.c, query->GotADD);
+
+ // CAUTION: MUST NOT do anything more with query after calling query->Callback(), because the client's
+ // callback function is allowed to do anything, including deleting this query and freeing its memory.
+ if (query->ServiceInfoQueryCallback && query->GotADD)
+ {
+ if (++query->Answers >= 100)
+ debugf("**** WARNING **** have given %lu answers for %##s (TXT) %#s...",
+ query->Answers, query->qSRV.qname.c, answer->rdata->u.txt.c);
+ query->ServiceInfoQueryCallback(m, query);
+ }
+}
mDNSlocal void FoundServiceInfo(mDNS *const m, DNSQuestion *question, const ResourceRecord *const answer, QC_result AddRecord)
- {
- ServiceInfoQuery *query = (ServiceInfoQuery *)question->QuestionContext;
- //LogInfo("FoundServiceInfo %d %s", AddRecord, RRDisplayString(m, answer));
- if (!AddRecord) return;
-
- if (answer->rrtype == kDNSType_A)
- {
- query->info->ip.type = mDNSAddrType_IPv4;
- query->info->ip.ip.v4 = answer->rdata->u.ipv4;
- }
- else if (answer->rrtype == kDNSType_AAAA)
- {
- query->info->ip.type = mDNSAddrType_IPv6;
- query->info->ip.ip.v6 = answer->rdata->u.ipv6;
- }
- else
- {
- debugf("FoundServiceInfo: answer %##s type %d (%s) unexpected", answer->name->c, answer->rrtype, DNSTypeName(answer->rrtype));
- return;
- }
-
- query->GotADD = mDNStrue;
- query->info->InterfaceID = answer->InterfaceID;
-
- verbosedebugf("FoundServiceInfo v%ld: %##s GotTXT=%d", query->info->ip.type, query->info->name.c, query->GotTXT);
-
- // CAUTION: MUST NOT do anything more with query after calling query->Callback(), because the client's
- // callback function is allowed to do anything, including deleting this query and freeing its memory.
- if (query->ServiceInfoQueryCallback && query->GotTXT)
- {
- if (++query->Answers >= 100)
- debugf(answer->rrtype == kDNSType_A ?
- "**** WARNING **** have given %lu answers for %##s (A) %.4a" :
- "**** WARNING **** have given %lu answers for %##s (AAAA) %.16a",
- query->Answers, query->qSRV.qname.c, &answer->rdata->u.data);
- query->ServiceInfoQueryCallback(m, query);
- }
- }
+{
+ ServiceInfoQuery *query = (ServiceInfoQuery *)question->QuestionContext;
+ //LogInfo("FoundServiceInfo %d %s", AddRecord, RRDisplayString(m, answer));
+ if (!AddRecord) return;
+
+ if (answer->rrtype == kDNSType_A)
+ {
+ query->info->ip.type = mDNSAddrType_IPv4;
+ query->info->ip.ip.v4 = answer->rdata->u.ipv4;
+ }
+ else if (answer->rrtype == kDNSType_AAAA)
+ {
+ query->info->ip.type = mDNSAddrType_IPv6;
+ query->info->ip.ip.v6 = answer->rdata->u.ipv6;
+ }
+ else
+ {
+ debugf("FoundServiceInfo: answer %##s type %d (%s) unexpected", answer->name->c, answer->rrtype, DNSTypeName(answer->rrtype));
+ return;
+ }
+
+ query->GotADD = mDNStrue;
+ query->info->InterfaceID = answer->InterfaceID;
+
+ verbosedebugf("FoundServiceInfo v%ld: %##s GotTXT=%d", query->info->ip.type, query->info->name.c, query->GotTXT);
+
+ // CAUTION: MUST NOT do anything more with query after calling query->Callback(), because the client's
+ // callback function is allowed to do anything, including deleting this query and freeing its memory.
+ if (query->ServiceInfoQueryCallback && query->GotTXT)
+ {
+ if (++query->Answers >= 100)
+ debugf(answer->rrtype == kDNSType_A ?
+ "**** WARNING **** have given %lu answers for %##s (A) %.4a" :
+ "**** WARNING **** have given %lu answers for %##s (AAAA) %.16a",
+ query->Answers, query->qSRV.qname.c, &answer->rdata->u.data);
+ query->ServiceInfoQueryCallback(m, query);
+ }
+}
// On entry, the client must have set the name and InterfaceID fields of the ServiceInfo structure
// If the query is not interface-specific, then InterfaceID may be zero
// Each time the Callback is invoked, the remainder of the fields will have been filled in
// In addition, InterfaceID will be updated to give the interface identifier corresponding to that response
mDNSexport mStatus mDNS_StartResolveService(mDNS *const m,
- ServiceInfoQuery *query, ServiceInfo *info, mDNSServiceInfoQueryCallback *Callback, void *Context)
- {
- mStatus status;
- mDNS_Lock(m);
-
- query->qSRV.ThisQInterval = -1; // So that mDNS_StopResolveService() knows whether to cancel this question
- query->qSRV.InterfaceID = info->InterfaceID;
- query->qSRV.Target = zeroAddr;
- AssignDomainName(&query->qSRV.qname, &info->name);
- query->qSRV.qtype = kDNSType_SRV;
- query->qSRV.qclass = kDNSClass_IN;
- query->qSRV.LongLived = mDNSfalse;
- query->qSRV.ExpectUnique = mDNStrue;
- query->qSRV.ForceMCast = mDNSfalse;
- query->qSRV.ReturnIntermed = mDNSfalse;
- query->qSRV.SuppressUnusable = mDNSfalse;
- query->qSRV.SearchListIndex = 0;
- query->qSRV.AppendSearchDomains = 0;
- query->qSRV.RetryWithSearchDomains = mDNSfalse;
- query->qSRV.TimeoutQuestion = 0;
- query->qSRV.WakeOnResolve = 0;
- query->qSRV.qnameOrig = mDNSNULL;
- query->qSRV.QuestionCallback = FoundServiceInfoSRV;
- query->qSRV.QuestionContext = query;
-
- query->qTXT.ThisQInterval = -1; // So that mDNS_StopResolveService() knows whether to cancel this question
- query->qTXT.InterfaceID = info->InterfaceID;
- query->qTXT.Target = zeroAddr;
- AssignDomainName(&query->qTXT.qname, &info->name);
- query->qTXT.qtype = kDNSType_TXT;
- query->qTXT.qclass = kDNSClass_IN;
- query->qTXT.LongLived = mDNSfalse;
- query->qTXT.ExpectUnique = mDNStrue;
- query->qTXT.ForceMCast = mDNSfalse;
- query->qTXT.ReturnIntermed = mDNSfalse;
- query->qTXT.SuppressUnusable = mDNSfalse;
- query->qTXT.SearchListIndex = 0;
- query->qTXT.AppendSearchDomains = 0;
- query->qTXT.RetryWithSearchDomains = mDNSfalse;
- query->qTXT.TimeoutQuestion = 0;
- query->qTXT.WakeOnResolve = 0;
- query->qTXT.qnameOrig = mDNSNULL;
- query->qTXT.QuestionCallback = FoundServiceInfoTXT;
- query->qTXT.QuestionContext = query;
-
- query->qAv4.ThisQInterval = -1; // So that mDNS_StopResolveService() knows whether to cancel this question
- query->qAv4.InterfaceID = info->InterfaceID;
- query->qAv4.Target = zeroAddr;
- query->qAv4.qname.c[0] = 0;
- query->qAv4.qtype = kDNSType_A;
- query->qAv4.qclass = kDNSClass_IN;
- query->qAv4.LongLived = mDNSfalse;
- query->qAv4.ExpectUnique = mDNStrue;
- query->qAv4.ForceMCast = mDNSfalse;
- query->qAv4.ReturnIntermed = mDNSfalse;
- query->qAv4.SuppressUnusable = mDNSfalse;
- query->qAv4.SearchListIndex = 0;
- query->qAv4.AppendSearchDomains = 0;
- query->qAv4.RetryWithSearchDomains = mDNSfalse;
- query->qAv4.TimeoutQuestion = 0;
- query->qAv4.WakeOnResolve = 0;
- query->qAv4.qnameOrig = mDNSNULL;
- query->qAv4.QuestionCallback = FoundServiceInfo;
- query->qAv4.QuestionContext = query;
-
- query->qAv6.ThisQInterval = -1; // So that mDNS_StopResolveService() knows whether to cancel this question
- query->qAv6.InterfaceID = info->InterfaceID;
- query->qAv6.Target = zeroAddr;
- query->qAv6.qname.c[0] = 0;
- query->qAv6.qtype = kDNSType_AAAA;
- query->qAv6.qclass = kDNSClass_IN;
- query->qAv6.LongLived = mDNSfalse;
- query->qAv6.ExpectUnique = mDNStrue;
- query->qAv6.ForceMCast = mDNSfalse;
- query->qAv6.ReturnIntermed = mDNSfalse;
- query->qAv6.SuppressUnusable = mDNSfalse;
- query->qAv6.SearchListIndex = 0;
- query->qAv6.AppendSearchDomains = 0;
- query->qAv6.RetryWithSearchDomains = mDNSfalse;
- query->qAv6.TimeoutQuestion = 0;
- query->qAv6.WakeOnResolve = 0;
- query->qAv6.qnameOrig = mDNSNULL;
- query->qAv6.QuestionCallback = FoundServiceInfo;
- query->qAv6.QuestionContext = query;
-
- query->GotSRV = mDNSfalse;
- query->GotTXT = mDNSfalse;
- query->GotADD = mDNSfalse;
- query->Answers = 0;
-
- query->info = info;
- query->ServiceInfoQueryCallback = Callback;
- query->ServiceInfoQueryContext = Context;
+ ServiceInfoQuery *query, ServiceInfo *info, mDNSServiceInfoQueryCallback *Callback, void *Context)
+{
+ mStatus status;
+ mDNS_Lock(m);
+
+ query->qSRV.ThisQInterval = -1; // So that mDNS_StopResolveService() knows whether to cancel this question
+ query->qSRV.InterfaceID = info->InterfaceID;
+ query->qSRV.flags = 0;
+ query->qSRV.Target = zeroAddr;
+ AssignDomainName(&query->qSRV.qname, &info->name);
+ query->qSRV.qtype = kDNSType_SRV;
+ query->qSRV.qclass = kDNSClass_IN;
+ query->qSRV.LongLived = mDNSfalse;
+ query->qSRV.ExpectUnique = mDNStrue;
+ query->qSRV.ForceMCast = mDNSfalse;
+ query->qSRV.ReturnIntermed = mDNSfalse;
+ query->qSRV.SuppressUnusable = mDNSfalse;
+ query->qSRV.DenyOnCellInterface = mDNSfalse;
+ query->qSRV.DenyOnExpInterface = mDNSfalse;
+ query->qSRV.SearchListIndex = 0;
+ query->qSRV.AppendSearchDomains = 0;
+ query->qSRV.RetryWithSearchDomains = mDNSfalse;
+ query->qSRV.TimeoutQuestion = 0;
+ query->qSRV.WakeOnResolve = 0;
+ query->qSRV.UseBackgroundTrafficClass = mDNSfalse;
+ query->qSRV.ValidationRequired = 0;
+ query->qSRV.ValidatingResponse = 0;
+ query->qSRV.ProxyQuestion = 0;
+ query->qSRV.qnameOrig = mDNSNULL;
+ query->qSRV.AnonInfo = mDNSNULL;
+ query->qSRV.QuestionCallback = FoundServiceInfoSRV;
+ query->qSRV.QuestionContext = query;
+
+ query->qTXT.ThisQInterval = -1; // So that mDNS_StopResolveService() knows whether to cancel this question
+ query->qTXT.InterfaceID = info->InterfaceID;
+ query->qTXT.flags = 0;
+ query->qTXT.Target = zeroAddr;
+ AssignDomainName(&query->qTXT.qname, &info->name);
+ query->qTXT.qtype = kDNSType_TXT;
+ query->qTXT.qclass = kDNSClass_IN;
+ query->qTXT.LongLived = mDNSfalse;
+ query->qTXT.ExpectUnique = mDNStrue;
+ query->qTXT.ForceMCast = mDNSfalse;
+ query->qTXT.ReturnIntermed = mDNSfalse;
+ query->qTXT.SuppressUnusable = mDNSfalse;
+ query->qTXT.DenyOnCellInterface = mDNSfalse;
+ query->qTXT.DenyOnExpInterface = mDNSfalse;
+ query->qTXT.SearchListIndex = 0;
+ query->qTXT.AppendSearchDomains = 0;
+ query->qTXT.RetryWithSearchDomains = mDNSfalse;
+ query->qTXT.TimeoutQuestion = 0;
+ query->qTXT.WakeOnResolve = 0;
+ query->qTXT.UseBackgroundTrafficClass = mDNSfalse;
+ query->qTXT.ValidationRequired = 0;
+ query->qTXT.ValidatingResponse = 0;
+ query->qTXT.ProxyQuestion = 0;
+ query->qTXT.qnameOrig = mDNSNULL;
+ query->qTXT.AnonInfo = mDNSNULL;
+ query->qTXT.QuestionCallback = FoundServiceInfoTXT;
+ query->qTXT.QuestionContext = query;
+
+ query->qAv4.ThisQInterval = -1; // So that mDNS_StopResolveService() knows whether to cancel this question
+ query->qAv4.InterfaceID = info->InterfaceID;
+ query->qAv4.flags = 0;
+ query->qAv4.Target = zeroAddr;
+ query->qAv4.qname.c[0] = 0;
+ query->qAv4.qtype = kDNSType_A;
+ query->qAv4.qclass = kDNSClass_IN;
+ query->qAv4.LongLived = mDNSfalse;
+ query->qAv4.ExpectUnique = mDNStrue;
+ query->qAv4.ForceMCast = mDNSfalse;
+ query->qAv4.ReturnIntermed = mDNSfalse;
+ query->qAv4.SuppressUnusable = mDNSfalse;
+ query->qAv4.DenyOnCellInterface = mDNSfalse;
+ query->qAv4.DenyOnExpInterface = mDNSfalse;
+ query->qAv4.SearchListIndex = 0;
+ query->qAv4.AppendSearchDomains = 0;
+ query->qAv4.RetryWithSearchDomains = mDNSfalse;
+ query->qAv4.TimeoutQuestion = 0;
+ query->qAv4.WakeOnResolve = 0;
+ query->qAv4.UseBackgroundTrafficClass = mDNSfalse;
+ query->qAv4.ValidationRequired = 0;
+ query->qAv4.ValidatingResponse = 0;
+ query->qAv4.ProxyQuestion = 0;
+ query->qAv4.qnameOrig = mDNSNULL;
+ query->qAv4.AnonInfo = mDNSNULL;
+ query->qAv4.QuestionCallback = FoundServiceInfo;
+ query->qAv4.QuestionContext = query;
+
+ query->qAv6.ThisQInterval = -1; // So that mDNS_StopResolveService() knows whether to cancel this question
+ query->qAv6.InterfaceID = info->InterfaceID;
+ query->qAv6.flags = 0;
+ query->qAv6.Target = zeroAddr;
+ query->qAv6.qname.c[0] = 0;
+ query->qAv6.qtype = kDNSType_AAAA;
+ query->qAv6.qclass = kDNSClass_IN;
+ query->qAv6.LongLived = mDNSfalse;
+ query->qAv6.ExpectUnique = mDNStrue;
+ query->qAv6.ForceMCast = mDNSfalse;
+ query->qAv6.ReturnIntermed = mDNSfalse;
+ query->qAv6.SuppressUnusable = mDNSfalse;
+ query->qAv6.DenyOnCellInterface = mDNSfalse;
+ query->qAv6.DenyOnExpInterface = mDNSfalse;
+ query->qAv6.SearchListIndex = 0;
+ query->qAv6.AppendSearchDomains = 0;
+ query->qAv6.RetryWithSearchDomains = mDNSfalse;
+ query->qAv6.TimeoutQuestion = 0;
+ query->qAv6.UseBackgroundTrafficClass = mDNSfalse;
+ query->qAv6.ValidationRequired = 0;
+ query->qAv6.ValidatingResponse = 0;
+ query->qAv6.ProxyQuestion = 0;
+ query->qAv6.qnameOrig = mDNSNULL;
+ query->qAv6.AnonInfo = mDNSNULL;
+ query->qAv6.QuestionCallback = FoundServiceInfo;
+ query->qAv6.QuestionContext = query;
+
+ query->GotSRV = mDNSfalse;
+ query->GotTXT = mDNSfalse;
+ query->GotADD = mDNSfalse;
+ query->Answers = 0;
+
+ query->info = info;
+ query->ServiceInfoQueryCallback = Callback;
+ query->ServiceInfoQueryContext = Context;
// info->name = Must already be set up by client
// info->interface = Must already be set up by client
- info->ip = zeroAddr;
- info->port = zeroIPPort;
- info->TXTlen = 0;
+ info->ip = zeroAddr;
+ info->port = zeroIPPort;
+ info->TXTlen = 0;
- // We use mDNS_StartQuery_internal here because we're already holding the lock
- status = mDNS_StartQuery_internal(m, &query->qSRV);
- if (status == mStatus_NoError) status = mDNS_StartQuery_internal(m, &query->qTXT);
- if (status != mStatus_NoError) mDNS_StopResolveService(m, query);
+ // We use mDNS_StartQuery_internal here because we're already holding the lock
+ status = mDNS_StartQuery_internal(m, &query->qSRV);
+ if (status == mStatus_NoError) status = mDNS_StartQuery_internal(m, &query->qTXT);
+ if (status != mStatus_NoError) mDNS_StopResolveService(m, query);
- mDNS_Unlock(m);
- return(status);
- }
+ mDNS_Unlock(m);
+ return(status);
+}
mDNSexport void mDNS_StopResolveService (mDNS *const m, ServiceInfoQuery *q)
- {
- mDNS_Lock(m);
- // We use mDNS_StopQuery_internal here because we're already holding the lock
- if (q->qSRV.ThisQInterval >= 0) mDNS_StopQuery_internal(m, &q->qSRV);
- if (q->qTXT.ThisQInterval >= 0) mDNS_StopQuery_internal(m, &q->qTXT);
- if (q->qAv4.ThisQInterval >= 0) mDNS_StopQuery_internal(m, &q->qAv4);
- if (q->qAv6.ThisQInterval >= 0) mDNS_StopQuery_internal(m, &q->qAv6);
- mDNS_Unlock(m);
- }
+{
+ mDNS_Lock(m);
+ // We use mDNS_StopQuery_internal here because we're already holding the lock
+ if (q->qSRV.ThisQInterval >= 0) mDNS_StopQuery_internal(m, &q->qSRV);
+ if (q->qTXT.ThisQInterval >= 0) mDNS_StopQuery_internal(m, &q->qTXT);
+ if (q->qAv4.ThisQInterval >= 0) mDNS_StopQuery_internal(m, &q->qAv4);
+ if (q->qAv6.ThisQInterval >= 0) mDNS_StopQuery_internal(m, &q->qAv6);
+ mDNS_Unlock(m);
+}
mDNSexport mStatus mDNS_GetDomains(mDNS *const m, DNSQuestion *const question, mDNS_DomainType DomainType, const domainname *dom,
- const mDNSInterfaceID InterfaceID, mDNSQuestionCallback *Callback, void *Context)
- {
- question->InterfaceID = InterfaceID;
- question->Target = zeroAddr;
- question->qtype = kDNSType_PTR;
- question->qclass = kDNSClass_IN;
- question->LongLived = mDNSfalse;
- question->ExpectUnique = mDNSfalse;
- question->ForceMCast = mDNSfalse;
- question->ReturnIntermed = mDNSfalse;
- question->SuppressUnusable = mDNSfalse;
- question->SearchListIndex = 0;
- question->AppendSearchDomains = 0;
- question->RetryWithSearchDomains = mDNSfalse;
- question->TimeoutQuestion = 0;
- question->WakeOnResolve = 0;
- question->qnameOrig = mDNSNULL;
- question->QuestionCallback = Callback;
- question->QuestionContext = Context;
- if (DomainType > mDNS_DomainTypeMax) return(mStatus_BadParamErr);
- if (!MakeDomainNameFromDNSNameString(&question->qname, mDNS_DomainTypeNames[DomainType])) return(mStatus_BadParamErr);
- if (!dom) dom = &localdomain;
- if (!AppendDomainName(&question->qname, dom)) return(mStatus_BadParamErr);
- return(mDNS_StartQuery(m, question));
- }
+ const mDNSInterfaceID InterfaceID, mDNSQuestionCallback *Callback, void *Context)
+{
+ question->InterfaceID = InterfaceID;
+ question->flags = 0;
+ question->Target = zeroAddr;
+ question->qtype = kDNSType_PTR;
+ question->qclass = kDNSClass_IN;
+ question->LongLived = mDNSfalse;
+ question->ExpectUnique = mDNSfalse;
+ question->ForceMCast = mDNSfalse;
+ question->ReturnIntermed = mDNSfalse;
+ question->SuppressUnusable = mDNSfalse;
+ question->DenyOnCellInterface = mDNSfalse;
+ question->DenyOnExpInterface = mDNSfalse;
+ question->SearchListIndex = 0;
+ question->AppendSearchDomains = 0;
+ question->RetryWithSearchDomains = mDNSfalse;
+ question->TimeoutQuestion = 0;
+ question->WakeOnResolve = 0;
+ question->UseBackgroundTrafficClass = mDNSfalse;
+ question->ValidationRequired = 0;
+ question->ValidatingResponse = 0;
+ question->ProxyQuestion = 0;
+ question->qnameOrig = mDNSNULL;
+ question->AnonInfo = mDNSNULL;
+ question->pid = mDNSPlatformGetPID();
+ question->QuestionCallback = Callback;
+ question->QuestionContext = Context;
+ if (DomainType > mDNS_DomainTypeMax) return(mStatus_BadParamErr);
+ if (!MakeDomainNameFromDNSNameString(&question->qname, mDNS_DomainTypeNames[DomainType])) return(mStatus_BadParamErr);
+ if (!dom) dom = &localdomain;
+ if (!AppendDomainName(&question->qname, dom)) return(mStatus_BadParamErr);
+ return(mDNS_StartQuery(m, question));
+}
// ***************************************************************************
#if COMPILER_LIKES_PRAGMA_MARK
#endif
mDNSexport mStatus mDNS_Register(mDNS *const m, AuthRecord *const rr)
- {
- mStatus status;
- mDNS_Lock(m);
- status = mDNS_Register_internal(m, rr);
- mDNS_Unlock(m);
- return(status);
- }
+{
+ mStatus status;
+ mDNS_Lock(m);
+ status = mDNS_Register_internal(m, rr);
+ mDNS_Unlock(m);
+ return(status);
+}
mDNSexport mStatus mDNS_Update(mDNS *const m, AuthRecord *const rr, mDNSu32 newttl,
- const mDNSu16 newrdlength, RData *const newrdata, mDNSRecordUpdateCallback *Callback)
- {
- if (!ValidateRData(rr->resrec.rrtype, newrdlength, newrdata))
- {
- LogMsg("Attempt to update record with invalid rdata: %s", GetRRDisplayString_rdb(&rr->resrec, &newrdata->u, m->MsgBuffer));
- return(mStatus_Invalid);
- }
-
- mDNS_Lock(m);
+ const mDNSu16 newrdlength, RData *const newrdata, mDNSRecordUpdateCallback *Callback)
+{
+ if (!ValidateRData(rr->resrec.rrtype, newrdlength, newrdata))
+ {
+ LogMsg("Attempt to update record with invalid rdata: %s", GetRRDisplayString_rdb(&rr->resrec, &newrdata->u, m->MsgBuffer));
+ return(mStatus_Invalid);
+ }
- // If TTL is unspecified, leave TTL unchanged
- if (newttl == 0) newttl = rr->resrec.rroriginalttl;
+ mDNS_Lock(m);
- // If we already have an update queued up which has not gone through yet, give the client a chance to free that memory
- if (rr->NewRData)
- {
- RData *n = rr->NewRData;
- rr->NewRData = mDNSNULL; // Clear the NewRData pointer ...
- if (rr->UpdateCallback)
- rr->UpdateCallback(m, rr, n, rr->newrdlength); // ...and let the client free this memory, if necessary
- }
+ // If TTL is unspecified, leave TTL unchanged
+ if (newttl == 0) newttl = rr->resrec.rroriginalttl;
+
+ // If we already have an update queued up which has not gone through yet, give the client a chance to free that memory
+ if (rr->NewRData)
+ {
+ RData *n = rr->NewRData;
+ rr->NewRData = mDNSNULL; // Clear the NewRData pointer ...
+ if (rr->UpdateCallback)
+ rr->UpdateCallback(m, rr, n, rr->newrdlength); // ...and let the client free this memory, if necessary
+ }
- rr->NewRData = newrdata;
- rr->newrdlength = newrdlength;
- rr->UpdateCallback = Callback;
+ rr->NewRData = newrdata;
+ rr->newrdlength = newrdlength;
+ rr->UpdateCallback = Callback;
#ifndef UNICAST_DISABLED
- if (rr->ARType != AuthRecordLocalOnly && rr->ARType != AuthRecordP2P && !IsLocalDomain(rr->resrec.name))
- {
- mStatus status = uDNS_UpdateRecord(m, rr);
- // The caller frees the memory on error, don't retain stale pointers
- if (status != mStatus_NoError) { rr->NewRData = mDNSNULL; rr->newrdlength = 0; }
- mDNS_Unlock(m);
- return(status);
- }
+ if (rr->ARType != AuthRecordLocalOnly && rr->ARType != AuthRecordP2P && !IsLocalDomain(rr->resrec.name))
+ {
+ mStatus status = uDNS_UpdateRecord(m, rr);
+ // The caller frees the memory on error, don't retain stale pointers
+ if (status != mStatus_NoError) { rr->NewRData = mDNSNULL; rr->newrdlength = 0; }
+ mDNS_Unlock(m);
+ return(status);
+ }
#endif
- if (RRLocalOnly(rr) || (rr->resrec.rroriginalttl == newttl &&
- rr->resrec.rdlength == newrdlength && mDNSPlatformMemSame(rr->resrec.rdata->u.data, newrdata->u.data, newrdlength)))
- CompleteRDataUpdate(m, rr);
- else
- {
- rr->AnnounceCount = InitialAnnounceCount;
- InitializeLastAPTime(m, rr);
- while (rr->NextUpdateCredit && m->timenow - rr->NextUpdateCredit >= 0) GrantUpdateCredit(rr);
- if (!rr->UpdateBlocked && rr->UpdateCredits) rr->UpdateCredits--;
- if (!rr->NextUpdateCredit) rr->NextUpdateCredit = NonZeroTime(m->timenow + kUpdateCreditRefreshInterval);
- if (rr->AnnounceCount > rr->UpdateCredits + 1) rr->AnnounceCount = (mDNSu8)(rr->UpdateCredits + 1);
- if (rr->UpdateCredits <= 5)
- {
- mDNSu32 delay = 6 - rr->UpdateCredits; // Delay 1 second, then 2, then 3, etc. up to 6 seconds maximum
- if (!rr->UpdateBlocked) rr->UpdateBlocked = NonZeroTime(m->timenow + (mDNSs32)delay * mDNSPlatformOneSecond);
- rr->ThisAPInterval *= 4;
- rr->LastAPTime = rr->UpdateBlocked - rr->ThisAPInterval;
- LogMsg("Excessive update rate for %##s; delaying announcement by %ld second%s",
- rr->resrec.name->c, delay, delay > 1 ? "s" : "");
- }
- rr->resrec.rroriginalttl = newttl;
- }
-
- mDNS_Unlock(m);
- return(mStatus_NoError);
- }
+ if (RRLocalOnly(rr) || (rr->resrec.rroriginalttl == newttl &&
+ rr->resrec.rdlength == newrdlength && mDNSPlatformMemSame(rr->resrec.rdata->u.data, newrdata->u.data, newrdlength)))
+ CompleteRDataUpdate(m, rr);
+ else
+ {
+ rr->AnnounceCount = InitialAnnounceCount;
+ InitializeLastAPTime(m, rr);
+ while (rr->NextUpdateCredit && m->timenow - rr->NextUpdateCredit >= 0) GrantUpdateCredit(rr);
+ if (!rr->UpdateBlocked && rr->UpdateCredits) rr->UpdateCredits--;
+ if (!rr->NextUpdateCredit) rr->NextUpdateCredit = NonZeroTime(m->timenow + kUpdateCreditRefreshInterval);
+ if (rr->AnnounceCount > rr->UpdateCredits + 1) rr->AnnounceCount = (mDNSu8)(rr->UpdateCredits + 1);
+ if (rr->UpdateCredits <= 5)
+ {
+ mDNSu32 delay = 6 - rr->UpdateCredits; // Delay 1 second, then 2, then 3, etc. up to 6 seconds maximum
+ if (!rr->UpdateBlocked) rr->UpdateBlocked = NonZeroTime(m->timenow + (mDNSs32)delay * mDNSPlatformOneSecond);
+ rr->ThisAPInterval *= 4;
+ rr->LastAPTime = rr->UpdateBlocked - rr->ThisAPInterval;
+ LogMsg("Excessive update rate for %##s; delaying announcement by %ld second%s",
+ rr->resrec.name->c, delay, delay > 1 ? "s" : "");
+ }
+ rr->resrec.rroriginalttl = newttl;
+ }
+
+ mDNS_Unlock(m);
+ return(mStatus_NoError);
+}
// Note: mDNS_Deregister calls mDNS_Deregister_internal which can call a user callback, which may change
// the record list and/or question list.
// Any code walking either list must use the CurrentQuestion and/or CurrentRecord mechanism to protect against this.
mDNSexport mStatus mDNS_Deregister(mDNS *const m, AuthRecord *const rr)
- {
- mStatus status;
- mDNS_Lock(m);
- status = mDNS_Deregister_internal(m, rr, mDNS_Dereg_normal);
- mDNS_Unlock(m);
- return(status);
- }
+{
+ mStatus status;
+ mDNS_Lock(m);
+ status = mDNS_Deregister_internal(m, rr, mDNS_Dereg_normal);
+ mDNS_Unlock(m);
+ return(status);
+}
// Circular reference: AdvertiseInterface references mDNS_HostNameCallback, which calls mDNS_SetFQDN, which call AdvertiseInterface
mDNSlocal void mDNS_HostNameCallback(mDNS *const m, AuthRecord *const rr, mStatus result);
mDNSlocal NetworkInterfaceInfo *FindFirstAdvertisedInterface(mDNS *const m)
- {
- NetworkInterfaceInfo *intf;
- for (intf = m->HostInterfaces; intf; intf = intf->next)
- if (intf->Advertise) break;
- return(intf);
- }
+{
+ NetworkInterfaceInfo *intf;
+ for (intf = m->HostInterfaces; intf; intf = intf->next)
+ if (intf->Advertise) break;
+ return(intf);
+}
mDNSlocal void AdvertiseInterface(mDNS *const m, NetworkInterfaceInfo *set)
- {
- char buffer[MAX_REVERSE_MAPPING_NAME];
- NetworkInterfaceInfo *primary = FindFirstAdvertisedInterface(m);
- if (!primary) primary = set; // If no existing advertised interface, this new NetworkInterfaceInfo becomes our new primary
+{
+ char buffer[MAX_REVERSE_MAPPING_NAME];
+ NetworkInterfaceInfo *primary;
+
+ if (!set->McastTxRx)
+ {
+ LogInfo("AdvertiseInterface: Returning, not multicast capable %s", set->ifname);
+ return;
+ }
+#if TARGET_OS_EMBEDDED
+ if (!m->AutoTargetServices)
+ {
+ LogInfo("AdvertiseInterface: Returning due to AutoTargetServices zero for %s", set->ifname);
+ return;
+ }
+#endif
+
+ primary = FindFirstAdvertisedInterface(m);
+ if (!primary) primary = set; // If no existing advertised interface, this new NetworkInterfaceInfo becomes our new primary
+
+ // If interface is marked as a direct link, we can assume the address record is unique
+ // and does not need to go through the probe phase of the probe/announce packet sequence.
+ mDNSu8 recordType = (set->DirectLink ? kDNSRecordTypeKnownUnique : kDNSRecordTypeUnique);
+
+ if (set->DirectLink)
+ LogInfo("AdvertiseInterface: Marking address record as kDNSRecordTypeKnownUnique for %s", set->ifname);
- // Send dynamic update for non-linklocal IPv4 Addresses
- mDNS_SetupResourceRecord(&set->RR_A, mDNSNULL, set->InterfaceID, kDNSType_A, kHostNameTTL, kDNSRecordTypeUnique, AuthRecordAny, mDNS_HostNameCallback, set);
- mDNS_SetupResourceRecord(&set->RR_PTR, mDNSNULL, set->InterfaceID, kDNSType_PTR, kHostNameTTL, kDNSRecordTypeKnownUnique, AuthRecordAny, mDNSNULL, mDNSNULL);
- mDNS_SetupResourceRecord(&set->RR_HINFO, mDNSNULL, set->InterfaceID, kDNSType_HINFO, kHostNameTTL, kDNSRecordTypeUnique, AuthRecordAny, mDNSNULL, mDNSNULL);
+ // Send dynamic update for non-linklocal IPv4 Addresses
+ mDNS_SetupResourceRecord(&set->RR_A, mDNSNULL, set->InterfaceID, kDNSType_A, kHostNameTTL, recordType, AuthRecordAny, mDNS_HostNameCallback, set);
+ mDNS_SetupResourceRecord(&set->RR_PTR, mDNSNULL, set->InterfaceID, kDNSType_PTR, kHostNameTTL, kDNSRecordTypeKnownUnique, AuthRecordAny, mDNSNULL, mDNSNULL);
+ mDNS_SetupResourceRecord(&set->RR_HINFO, mDNSNULL, set->InterfaceID, kDNSType_HINFO, kHostNameTTL, kDNSRecordTypeUnique, AuthRecordAny, mDNSNULL, mDNSNULL);
#if ANSWER_REMOTE_HOSTNAME_QUERIES
- set->RR_A .AllowRemoteQuery = mDNStrue;
- set->RR_PTR .AllowRemoteQuery = mDNStrue;
- set->RR_HINFO.AllowRemoteQuery = mDNStrue;
+ set->RR_A.AllowRemoteQuery = mDNStrue;
+ set->RR_PTR.AllowRemoteQuery = mDNStrue;
+ set->RR_HINFO.AllowRemoteQuery = mDNStrue;
#endif
- // 1. Set up Address record to map from host name ("foo.local.") to IP address
- // 2. Set up reverse-lookup PTR record to map from our address back to our host name
- AssignDomainName(&set->RR_A.namestorage, &m->MulticastHostname);
- if (set->ip.type == mDNSAddrType_IPv4)
- {
- set->RR_A.resrec.rrtype = kDNSType_A;
- set->RR_A.resrec.rdata->u.ipv4 = set->ip.ip.v4;
- // Note: This is reverse order compared to a normal dotted-decimal IP address, so we can't use our customary "%.4a" format code
- mDNS_snprintf(buffer, sizeof(buffer), "%d.%d.%d.%d.in-addr.arpa.",
- set->ip.ip.v4.b[3], set->ip.ip.v4.b[2], set->ip.ip.v4.b[1], set->ip.ip.v4.b[0]);
- }
- else if (set->ip.type == mDNSAddrType_IPv6)
- {
- int i;
- set->RR_A.resrec.rrtype = kDNSType_AAAA;
- set->RR_A.resrec.rdata->u.ipv6 = set->ip.ip.v6;
- for (i = 0; i < 16; i++)
- {
- static const char hexValues[] = "0123456789ABCDEF";
- buffer[i * 4 ] = hexValues[set->ip.ip.v6.b[15 - i] & 0x0F];
- buffer[i * 4 + 1] = '.';
- buffer[i * 4 + 2] = hexValues[set->ip.ip.v6.b[15 - i] >> 4];
- buffer[i * 4 + 3] = '.';
- }
- mDNS_snprintf(&buffer[64], sizeof(buffer)-64, "ip6.arpa.");
- }
-
- MakeDomainNameFromDNSNameString(&set->RR_PTR.namestorage, buffer);
- set->RR_PTR.AutoTarget = Target_AutoHost; // Tell mDNS that the target of this PTR is to be kept in sync with our host name
- set->RR_PTR.ForceMCast = mDNStrue; // This PTR points to our dot-local name, so don't ever try to write it into a uDNS server
-
- set->RR_A.RRSet = &primary->RR_A; // May refer to self
-
- mDNS_Register_internal(m, &set->RR_A);
- mDNS_Register_internal(m, &set->RR_PTR);
-
- if (!NO_HINFO && m->HIHardware.c[0] > 0 && m->HISoftware.c[0] > 0 && m->HIHardware.c[0] + m->HISoftware.c[0] <= 254)
- {
- mDNSu8 *p = set->RR_HINFO.resrec.rdata->u.data;
- AssignDomainName(&set->RR_HINFO.namestorage, &m->MulticastHostname);
- set->RR_HINFO.DependentOn = &set->RR_A;
- mDNSPlatformMemCopy(p, &m->HIHardware, 1 + (mDNSu32)m->HIHardware.c[0]);
- p += 1 + (int)p[0];
- mDNSPlatformMemCopy(p, &m->HISoftware, 1 + (mDNSu32)m->HISoftware.c[0]);
- mDNS_Register_internal(m, &set->RR_HINFO);
- }
- else
- {
- debugf("Not creating HINFO record: platform support layer provided no information");
- set->RR_HINFO.resrec.RecordType = kDNSRecordTypeUnregistered;
- }
- }
+ // 1. Set up Address record to map from host name ("foo.local.") to IP address
+ // 2. Set up reverse-lookup PTR record to map from our address back to our host name
+ AssignDomainName(&set->RR_A.namestorage, &m->MulticastHostname);
+ if (set->ip.type == mDNSAddrType_IPv4)
+ {
+ set->RR_A.resrec.rrtype = kDNSType_A;
+ set->RR_A.resrec.rdata->u.ipv4 = set->ip.ip.v4;
+ // Note: This is reverse order compared to a normal dotted-decimal IP address, so we can't use our customary "%.4a" format code
+ mDNS_snprintf(buffer, sizeof(buffer), "%d.%d.%d.%d.in-addr.arpa.",
+ set->ip.ip.v4.b[3], set->ip.ip.v4.b[2], set->ip.ip.v4.b[1], set->ip.ip.v4.b[0]);
+ }
+ else if (set->ip.type == mDNSAddrType_IPv6)
+ {
+ int i;
+ set->RR_A.resrec.rrtype = kDNSType_AAAA;
+ set->RR_A.resrec.rdata->u.ipv6 = set->ip.ip.v6;
+ for (i = 0; i < 16; i++)
+ {
+ static const char hexValues[] = "0123456789ABCDEF";
+ buffer[i * 4 ] = hexValues[set->ip.ip.v6.b[15 - i] & 0x0F];
+ buffer[i * 4 + 1] = '.';
+ buffer[i * 4 + 2] = hexValues[set->ip.ip.v6.b[15 - i] >> 4];
+ buffer[i * 4 + 3] = '.';
+ }
+ mDNS_snprintf(&buffer[64], sizeof(buffer)-64, "ip6.arpa.");
+ }
+
+ MakeDomainNameFromDNSNameString(&set->RR_PTR.namestorage, buffer);
+ set->RR_PTR.AutoTarget = Target_AutoHost; // Tell mDNS that the target of this PTR is to be kept in sync with our host name
+ set->RR_PTR.ForceMCast = mDNStrue; // This PTR points to our dot-local name, so don't ever try to write it into a uDNS server
+
+ set->RR_A.RRSet = &primary->RR_A; // May refer to self
+
+ mDNS_Register_internal(m, &set->RR_A);
+ mDNS_Register_internal(m, &set->RR_PTR);
+
+#if APPLE_OSX_mDNSResponder
+ // must be after the mDNS_Register_internal() calls so that records have complete rdata fields, etc
+ D2D_start_advertising_interface(set);
+#endif // APPLE_OSX_mDNSResponder
+
+ if (!NO_HINFO && m->HIHardware.c[0] > 0 && m->HISoftware.c[0] > 0 && m->HIHardware.c[0] + m->HISoftware.c[0] <= 254)
+ {
+ mDNSu8 *p = set->RR_HINFO.resrec.rdata->u.data;
+ AssignDomainName(&set->RR_HINFO.namestorage, &m->MulticastHostname);
+ set->RR_HINFO.DependentOn = &set->RR_A;
+ mDNSPlatformMemCopy(p, &m->HIHardware, 1 + (mDNSu32)m->HIHardware.c[0]);
+ p += 1 + (int)p[0];
+ mDNSPlatformMemCopy(p, &m->HISoftware, 1 + (mDNSu32)m->HISoftware.c[0]);
+ mDNS_Register_internal(m, &set->RR_HINFO);
+ }
+ else
+ {
+ debugf("Not creating HINFO record: platform support layer provided no information");
+ set->RR_HINFO.resrec.RecordType = kDNSRecordTypeUnregistered;
+ }
+}
mDNSlocal void DeadvertiseInterface(mDNS *const m, NetworkInterfaceInfo *set)
- {
- NetworkInterfaceInfo *intf;
-
+{
+ NetworkInterfaceInfo *intf;
+
// If we still have address records referring to this one, update them
- NetworkInterfaceInfo *primary = FindFirstAdvertisedInterface(m);
- AuthRecord *A = primary ? &primary->RR_A : mDNSNULL;
- for (intf = m->HostInterfaces; intf; intf = intf->next)
- if (intf->RR_A.RRSet == &set->RR_A)
- intf->RR_A.RRSet = A;
-
- // Unregister these records.
- // When doing the mDNS_Exit processing, we first call DeadvertiseInterface for each interface, so by the time the platform
- // support layer gets to call mDNS_DeregisterInterface, the address and PTR records have already been deregistered for it.
- // Also, in the event of a name conflict, one or more of our records will have been forcibly deregistered.
- // To avoid unnecessary and misleading warning messages, we check the RecordType before calling mDNS_Deregister_internal().
- if (set->RR_A. resrec.RecordType) mDNS_Deregister_internal(m, &set->RR_A, mDNS_Dereg_normal);
- if (set->RR_PTR. resrec.RecordType) mDNS_Deregister_internal(m, &set->RR_PTR, mDNS_Dereg_normal);
- if (set->RR_HINFO.resrec.RecordType) mDNS_Deregister_internal(m, &set->RR_HINFO, mDNS_Dereg_normal);
- }
+ NetworkInterfaceInfo *primary = FindFirstAdvertisedInterface(m);
+ AuthRecord *A = primary ? &primary->RR_A : mDNSNULL;
+ for (intf = m->HostInterfaces; intf; intf = intf->next)
+ if (intf->RR_A.RRSet == &set->RR_A)
+ intf->RR_A.RRSet = A;
+
+ // Unregister these records.
+ // When doing the mDNS_Exit processing, we first call DeadvertiseInterface for each interface, so by the time the platform
+ // support layer gets to call mDNS_DeregisterInterface, the address and PTR records have already been deregistered for it.
+ // Also, in the event of a name conflict, one or more of our records will have been forcibly deregistered.
+ // To avoid unnecessary and misleading warning messages, we check the RecordType before calling mDNS_Deregister_internal().
+ if (set->RR_A.resrec.RecordType) mDNS_Deregister_internal(m, &set->RR_A, mDNS_Dereg_normal);
+ if (set->RR_PTR.resrec.RecordType) mDNS_Deregister_internal(m, &set->RR_PTR, mDNS_Dereg_normal);
+ if (set->RR_HINFO.resrec.RecordType) mDNS_Deregister_internal(m, &set->RR_HINFO, mDNS_Dereg_normal);
+
+#if APPLE_OSX_mDNSResponder
+ D2D_stop_advertising_interface(set);
+#endif // APPLE_OSX_mDNSResponder
+
+}
+
+mDNSlocal void AdvertiseAllInterfaceRecords(mDNS *const m)
+{
+ NetworkInterfaceInfo *intf;
+ for (intf = m->HostInterfaces; intf; intf = intf->next)
+ {
+ if (intf->Advertise)
+ {
+ LogInfo("AdvertiseInterface: Advertising for ifname %s", intf->ifname);
+ AdvertiseInterface(m, intf);
+ }
+ }
+}
+
+mDNSlocal void DeadvertiseAllInterfaceRecords(mDNS *const m)
+{
+#if TARGET_OS_EMBEDDED
+ NetworkInterfaceInfo *intf;
+ for (intf = m->HostInterfaces; intf; intf = intf->next)
+ {
+ if (intf->Advertise)
+ {
+ LogInfo("DeadvertiseInterface: Deadvertising for ifname %s", intf->ifname);
+ DeadvertiseInterface(m, intf);
+ }
+ }
+#else
+ (void) m; //unused
+#endif
+}
mDNSexport void mDNS_SetFQDN(mDNS *const m)
- {
- domainname newmname;
- NetworkInterfaceInfo *intf;
- AuthRecord *rr;
- newmname.c[0] = 0;
+{
+ domainname newmname;
+ NetworkInterfaceInfo *intf;
+ AuthRecord *rr;
+ newmname.c[0] = 0;
- if (!AppendDomainLabel(&newmname, &m->hostlabel)) { LogMsg("ERROR: mDNS_SetFQDN: Cannot create MulticastHostname"); return; }
- if (!AppendLiteralLabelString(&newmname, "local")) { LogMsg("ERROR: mDNS_SetFQDN: Cannot create MulticastHostname"); return; }
+ if (!AppendDomainLabel(&newmname, &m->hostlabel)) { LogMsg("ERROR: mDNS_SetFQDN: Cannot create MulticastHostname"); return; }
+ if (!AppendLiteralLabelString(&newmname, "local")) { LogMsg("ERROR: mDNS_SetFQDN: Cannot create MulticastHostname"); return; }
- mDNS_Lock(m);
+ mDNS_Lock(m);
- if (SameDomainNameCS(&m->MulticastHostname, &newmname)) debugf("mDNS_SetFQDN - hostname unchanged");
- else
- {
- AssignDomainName(&m->MulticastHostname, &newmname);
-
- // 1. Stop advertising our address records on all interfaces
- for (intf = m->HostInterfaces; intf; intf = intf->next)
- if (intf->Advertise) DeadvertiseInterface(m, intf);
-
- // 2. Start advertising our address records using the new name
- for (intf = m->HostInterfaces; intf; intf = intf->next)
- if (intf->Advertise) AdvertiseInterface(m, intf);
- }
-
- // 3. Make sure that any AutoTarget SRV records (and the like) get updated
- for (rr = m->ResourceRecords; rr; rr=rr->next) if (rr->AutoTarget) SetTargetToHostName(m, rr);
- for (rr = m->DuplicateRecords; rr; rr=rr->next) if (rr->AutoTarget) SetTargetToHostName(m, rr);
-
- mDNS_Unlock(m);
- }
+ if (SameDomainNameCS(&m->MulticastHostname, &newmname)) debugf("mDNS_SetFQDN - hostname unchanged");
+ else
+ {
+ AssignDomainName(&m->MulticastHostname, &newmname);
+
+ // 1. Stop advertising our address records on all interfaces
+ for (intf = m->HostInterfaces; intf; intf = intf->next)
+ if (intf->Advertise) DeadvertiseInterface(m, intf);
+
+ // 2. Start advertising our address records using the new name
+ for (intf = m->HostInterfaces; intf; intf = intf->next)
+ if (intf->Advertise) AdvertiseInterface(m, intf);
+ }
+
+ // 3. Make sure that any AutoTarget SRV records (and the like) get updated
+ for (rr = m->ResourceRecords; rr; rr=rr->next) if (rr->AutoTarget) SetTargetToHostName(m, rr);
+ for (rr = m->DuplicateRecords; rr; rr=rr->next) if (rr->AutoTarget) SetTargetToHostName(m, rr);
+
+ mDNS_Unlock(m);
+}
mDNSlocal void mDNS_HostNameCallback(mDNS *const m, AuthRecord *const rr, mStatus result)
- {
- (void)rr; // Unused parameter
-
- #if MDNS_DEBUGMSGS
- {
- char *msg = "Unknown result";
- if (result == mStatus_NoError) msg = "Name registered";
- else if (result == mStatus_NameConflict) msg = "Name conflict";
- debugf("mDNS_HostNameCallback: %##s (%s) %s (%ld)", rr->resrec.name->c, DNSTypeName(rr->resrec.rrtype), msg, result);
- }
- #endif
-
- if (result == mStatus_NoError)
- {
- // Notify the client that the host name is successfully registered
- if (m->MainCallback)
- m->MainCallback(m, mStatus_NoError);
- }
- else if (result == mStatus_NameConflict)
- {
- domainlabel oldlabel = m->hostlabel;
-
- // 1. First give the client callback a chance to pick a new name
- if (m->MainCallback)
- m->MainCallback(m, mStatus_NameConflict);
-
- // 2. If the client callback didn't do it, add (or increment) an index ourselves
- // This needs to be case-INSENSITIVE compare, because we need to know that the name has been changed so as to
- // remedy the conflict, and a name that differs only in capitalization will just suffer the exact same conflict again.
- if (SameDomainLabel(m->hostlabel.c, oldlabel.c))
- IncrementLabelSuffix(&m->hostlabel, mDNSfalse);
-
- // 3. Generate the FQDNs from the hostlabel,
- // and make sure all SRV records, etc., are updated to reference our new hostname
- mDNS_SetFQDN(m);
- LogMsg("Local Hostname %#s.local already in use; will try %#s.local instead", oldlabel.c, m->hostlabel.c);
- }
- else if (result == mStatus_MemFree)
- {
- // .local hostnames do not require goodbyes - we ignore the MemFree (which is sent directly by
- // mDNS_Deregister_internal), and allow the caller to deallocate immediately following mDNS_DeadvertiseInterface
- debugf("mDNS_HostNameCallback: MemFree (ignored)");
- }
- else
- LogMsg("mDNS_HostNameCallback: Unknown error %d for registration of record %s", result, rr->resrec.name->c);
- }
+{
+ (void)rr; // Unused parameter
+
+ #if MDNS_DEBUGMSGS
+ {
+ char *msg = "Unknown result";
+ if (result == mStatus_NoError) msg = "Name registered";
+ else if (result == mStatus_NameConflict) msg = "Name conflict";
+ debugf("mDNS_HostNameCallback: %##s (%s) %s (%ld)", rr->resrec.name->c, DNSTypeName(rr->resrec.rrtype), msg, result);
+ }
+ #endif
+
+ if (result == mStatus_NoError)
+ {
+ // Notify the client that the host name is successfully registered
+ if (m->MainCallback)
+ m->MainCallback(m, mStatus_NoError);
+ }
+ else if (result == mStatus_NameConflict)
+ {
+ domainlabel oldlabel = m->hostlabel;
+
+ // 1. First give the client callback a chance to pick a new name
+ if (m->MainCallback)
+ m->MainCallback(m, mStatus_NameConflict);
+
+ // 2. If the client callback didn't do it, add (or increment) an index ourselves
+ // This needs to be case-INSENSITIVE compare, because we need to know that the name has been changed so as to
+ // remedy the conflict, and a name that differs only in capitalization will just suffer the exact same conflict again.
+ if (SameDomainLabel(m->hostlabel.c, oldlabel.c))
+ IncrementLabelSuffix(&m->hostlabel, mDNSfalse);
+
+ // 3. Generate the FQDNs from the hostlabel,
+ // and make sure all SRV records, etc., are updated to reference our new hostname
+ mDNS_SetFQDN(m);
+ LogMsg("Local Hostname %#s.local already in use; will try %#s.local instead", oldlabel.c, m->hostlabel.c);
+ }
+ else if (result == mStatus_MemFree)
+ {
+ // .local hostnames do not require goodbyes - we ignore the MemFree (which is sent directly by
+ // mDNS_Deregister_internal), and allow the caller to deallocate immediately following mDNS_DeadvertiseInterface
+ debugf("mDNS_HostNameCallback: MemFree (ignored)");
+ }
+ else
+ LogMsg("mDNS_HostNameCallback: Unknown error %d for registration of record %s", result, rr->resrec.name->c);
+}
mDNSlocal void UpdateInterfaceProtocols(mDNS *const m, NetworkInterfaceInfo *active)
- {
- NetworkInterfaceInfo *intf;
- active->IPv4Available = mDNSfalse;
- active->IPv6Available = mDNSfalse;
- for (intf = m->HostInterfaces; intf; intf = intf->next)
- if (intf->InterfaceID == active->InterfaceID)
- {
- if (intf->ip.type == mDNSAddrType_IPv4 && intf->McastTxRx) active->IPv4Available = mDNStrue;
- if (intf->ip.type == mDNSAddrType_IPv6 && intf->McastTxRx) active->IPv6Available = mDNStrue;
- }
- }
+{
+ NetworkInterfaceInfo *intf;
+ active->IPv4Available = mDNSfalse;
+ active->IPv6Available = mDNSfalse;
+ for (intf = m->HostInterfaces; intf; intf = intf->next)
+ if (intf->InterfaceID == active->InterfaceID)
+ {
+ if (intf->ip.type == mDNSAddrType_IPv4 && intf->McastTxRx) active->IPv4Available = mDNStrue;
+ if (intf->ip.type == mDNSAddrType_IPv6 && intf->McastTxRx) active->IPv6Available = mDNStrue;
+ }
+}
mDNSlocal void RestartRecordGetZoneData(mDNS * const m)
- {
- AuthRecord *rr;
- LogInfo("RestartRecordGetZoneData: ResourceRecords");
- for (rr = m->ResourceRecords; rr; rr=rr->next)
- if (AuthRecord_uDNS(rr) && rr->state != regState_NoTarget)
- {
- debugf("RestartRecordGetZoneData: StartGetZoneData for %##s", rr->resrec.name->c);
- // Zero out the updateid so that if we have a pending response from the server, it won't
- // be accepted as a valid response. If we accept the response, we might free the new "nta"
- if (rr->nta) { rr->updateid = zeroID; CancelGetZoneData(m, rr->nta); }
- rr->nta = StartGetZoneData(m, rr->resrec.name, ZoneServiceUpdate, RecordRegistrationGotZoneData, rr);
- }
- }
+{
+ AuthRecord *rr;
+ LogInfo("RestartRecordGetZoneData: ResourceRecords");
+ for (rr = m->ResourceRecords; rr; rr=rr->next)
+ if (AuthRecord_uDNS(rr) && rr->state != regState_NoTarget)
+ {
+ debugf("RestartRecordGetZoneData: StartGetZoneData for %##s", rr->resrec.name->c);
+ // Zero out the updateid so that if we have a pending response from the server, it won't
+ // be accepted as a valid response. If we accept the response, we might free the new "nta"
+ if (rr->nta) { rr->updateid = zeroID; CancelGetZoneData(m, rr->nta); }
+ rr->nta = StartGetZoneData(m, rr->resrec.name, ZoneServiceUpdate, RecordRegistrationGotZoneData, rr);
+ }
+}
mDNSlocal void InitializeNetWakeState(mDNS *const m, NetworkInterfaceInfo *set)
- {
- int i;
- set->NetWakeBrowse.ThisQInterval = -1;
- for (i=0; i<3; i++)
- {
- set->NetWakeResolve[i].ThisQInterval = -1;
- set->SPSAddr[i].type = mDNSAddrType_None;
- }
- set->NextSPSAttempt = -1;
- set->NextSPSAttemptTime = m->timenow;
- }
+{
+ int i;
+ // We initialize ThisQInterval to -1 indicating that the question has not been started
+ // yet. If the question (browse) is started later during interface registration, it will
+ // be stopped during interface deregistration. We can't sanity check to see if the
+ // question has been stopped or not before initializing it to -1 because we need to
+ // initialize it to -1 the very first time.
+
+ set->NetWakeBrowse.ThisQInterval = -1;
+ for (i=0; i<3; i++)
+ {
+ set->NetWakeResolve[i].ThisQInterval = -1;
+ set->SPSAddr[i].type = mDNSAddrType_None;
+ }
+ set->NextSPSAttempt = -1;
+ set->NextSPSAttemptTime = m->timenow;
+}
mDNSexport void mDNS_ActivateNetWake_internal(mDNS *const m, NetworkInterfaceInfo *set)
- {
- NetworkInterfaceInfo *p = m->HostInterfaces;
- while (p && p != set) p=p->next;
- if (!p) { LogMsg("mDNS_ActivateNetWake_internal: NetworkInterfaceInfo %p not found in active list", set); return; }
-
- if (set->InterfaceActive)
- {
- LogSPS("ActivateNetWake for %s (%#a)", set->ifname, &set->ip);
- mDNS_StartBrowse_internal(m, &set->NetWakeBrowse, &SleepProxyServiceType, &localdomain, set->InterfaceID, mDNSfalse, m->SPSBrowseCallback, set);
- }
- }
+{
+ NetworkInterfaceInfo *p = m->HostInterfaces;
+ while (p && p != set) p=p->next;
+ if (!p) { LogMsg("mDNS_ActivateNetWake_internal: NetworkInterfaceInfo %p not found in active list", set); return; }
+
+ if (set->InterfaceActive)
+ {
+ LogSPS("ActivateNetWake for %s (%#a)", set->ifname, &set->ip);
+ mDNS_StartBrowse_internal(m, &set->NetWakeBrowse, &SleepProxyServiceType, &localdomain, mDNSNULL, set->InterfaceID, 0, mDNSfalse, mDNSfalse, m->SPSBrowseCallback, set);
+ }
+}
mDNSexport void mDNS_DeactivateNetWake_internal(mDNS *const m, NetworkInterfaceInfo *set)
- {
- NetworkInterfaceInfo *p = m->HostInterfaces;
- while (p && p != set) p=p->next;
- if (!p) { LogMsg("mDNS_DeactivateNetWake_internal: NetworkInterfaceInfo %p not found in active list", set); return; }
-
- if (set->NetWakeBrowse.ThisQInterval >= 0)
- {
- int i;
- LogSPS("DeactivateNetWake for %s (%#a)", set->ifname, &set->ip);
-
- // Stop our browse and resolve operations
- mDNS_StopQuery_internal(m, &set->NetWakeBrowse);
- for (i=0; i<3; i++) if (set->NetWakeResolve[i].ThisQInterval >= 0) mDNS_StopQuery_internal(m, &set->NetWakeResolve[i]);
-
- // Make special call to the browse callback to let it know it can to remove all records for this interface
- if (m->SPSBrowseCallback)
- {
- mDNS_DropLockBeforeCallback(); // Allow client to legally make mDNS API calls from the callback
- m->SPSBrowseCallback(m, &set->NetWakeBrowse, mDNSNULL, mDNSfalse);
- mDNS_ReclaimLockAfterCallback(); // Decrement mDNS_reentrancy to block mDNS API calls again
- }
-
- // Reset our variables back to initial state, so we're ready for when NetWake is turned back on
- // (includes resetting NetWakeBrowse.ThisQInterval back to -1)
- InitializeNetWakeState(m, set);
- }
- }
+{
+ NetworkInterfaceInfo *p = m->HostInterfaces;
+ while (p && p != set) p=p->next;
+ if (!p) { LogMsg("mDNS_DeactivateNetWake_internal: NetworkInterfaceInfo %p not found in active list", set); return; }
+
+ // Note: We start the browse only if the interface is NetWake capable and we use this to
+ // stop the resolves also. Hence, the resolves should not be started without the browse
+ // being started i.e, resolves should not happen unless NetWake capable which is
+ // guaranteed by BeginSleepProcessing.
+ if (set->NetWakeBrowse.ThisQInterval >= 0)
+ {
+ int i;
+ LogSPS("DeactivateNetWake for %s (%#a)", set->ifname, &set->ip);
+
+ // Stop our browse and resolve operations
+ mDNS_StopQuery_internal(m, &set->NetWakeBrowse);
+ for (i=0; i<3; i++) if (set->NetWakeResolve[i].ThisQInterval >= 0) mDNS_StopQuery_internal(m, &set->NetWakeResolve[i]);
+
+ // Make special call to the browse callback to let it know it can to remove all records for this interface
+ if (m->SPSBrowseCallback)
+ {
+ mDNS_DropLockBeforeCallback(); // Allow client to legally make mDNS API calls from the callback
+ m->SPSBrowseCallback(m, &set->NetWakeBrowse, mDNSNULL, mDNSfalse);
+ mDNS_ReclaimLockAfterCallback(); // Decrement mDNS_reentrancy to block mDNS API calls again
+ }
+
+ // Reset our variables back to initial state, so we're ready for when NetWake is turned back on
+ // (includes resetting NetWakeBrowse.ThisQInterval back to -1)
+ InitializeNetWakeState(m, set);
+ }
+}
mDNSexport mStatus mDNS_RegisterInterface(mDNS *const m, NetworkInterfaceInfo *set, mDNSBool flapping)
- {
- AuthRecord *rr;
- mDNSBool FirstOfType = mDNStrue;
- NetworkInterfaceInfo **p = &m->HostInterfaces;
+{
+ AuthRecord *rr;
+ mDNSBool FirstOfType = mDNStrue;
+ NetworkInterfaceInfo **p = &m->HostInterfaces;
- if (!set->InterfaceID)
- { LogMsg("mDNS_RegisterInterface: Error! Tried to register a NetworkInterfaceInfo %#a with zero InterfaceID", &set->ip); return(mStatus_Invalid); }
+ if (!set->InterfaceID)
+ { LogMsg("mDNS_RegisterInterface: Error! Tried to register a NetworkInterfaceInfo %#a with zero InterfaceID", &set->ip); return(mStatus_Invalid); }
- if (!mDNSAddressIsValidNonZero(&set->mask))
- { LogMsg("mDNS_RegisterInterface: Error! Tried to register a NetworkInterfaceInfo %#a with invalid mask %#a", &set->ip, &set->mask); return(mStatus_Invalid); }
+ if (!mDNSAddressIsValidNonZero(&set->mask))
+ { LogMsg("mDNS_RegisterInterface: Error! Tried to register a NetworkInterfaceInfo %#a with invalid mask %#a", &set->ip, &set->mask); return(mStatus_Invalid); }
- mDNS_Lock(m);
-
- // Assume this interface will be active now, unless we find a duplicate already in the list
- set->InterfaceActive = mDNStrue;
- set->IPv4Available = (mDNSu8)(set->ip.type == mDNSAddrType_IPv4 && set->McastTxRx);
- set->IPv6Available = (mDNSu8)(set->ip.type == mDNSAddrType_IPv6 && set->McastTxRx);
-
- InitializeNetWakeState(m, set);
-
- // Scan list to see if this InterfaceID is already represented
- while (*p)
- {
- if (*p == set)
- {
- LogMsg("mDNS_RegisterInterface: Error! Tried to register a NetworkInterfaceInfo that's already in the list");
- mDNS_Unlock(m);
- return(mStatus_AlreadyRegistered);
- }
-
- if ((*p)->InterfaceID == set->InterfaceID)
- {
- // This InterfaceID already represented by a different interface in the list, so mark this instance inactive for now
- set->InterfaceActive = mDNSfalse;
- if (set->ip.type == (*p)->ip.type) FirstOfType = mDNSfalse;
- if (set->ip.type == mDNSAddrType_IPv4 && set->McastTxRx) (*p)->IPv4Available = mDNStrue;
- if (set->ip.type == mDNSAddrType_IPv6 && set->McastTxRx) (*p)->IPv6Available = mDNStrue;
- }
-
- p=&(*p)->next;
- }
-
- set->next = mDNSNULL;
- *p = set;
-
- if (set->Advertise)
- AdvertiseInterface(m, set);
+ mDNS_Lock(m);
- LogInfo("mDNS_RegisterInterface: InterfaceID %p %s (%#a) %s", set->InterfaceID, set->ifname, &set->ip,
- set->InterfaceActive ?
- "not represented in list; marking active and retriggering queries" :
- "already represented in list; marking inactive for now");
-
- if (set->NetWake) mDNS_ActivateNetWake_internal(m, set);
-
- // In early versions of OS X the IPv6 address remains on an interface even when the interface is turned off,
- // giving the false impression that there's an active representative of this interface when there really isn't.
- // Therefore, when registering an interface, we want to re-trigger our questions and re-probe our Resource Records,
- // even if we believe that we previously had an active representative of this interface.
- if (set->McastTxRx && (FirstOfType || set->InterfaceActive))
- {
- DNSQuestion *q;
- // Normally, after an interface comes up, we pause half a second before beginning probing.
- // This is to guard against cases where there's rapid interface changes, where we could be confused by
- // seeing packets we ourselves sent just moments ago (perhaps when this interface had a different address)
- // which are then echoed back after a short delay by some Ethernet switches and some 802.11 base stations.
- // We don't want to do a probe, and then see a stale echo of an announcement we ourselves sent,
- // and think it's a conflicting answer to our probe.
- // In the case of a flapping interface, we pause for five seconds, and reduce the announcement count to one packet.
- const mDNSs32 probedelay = flapping ? mDNSPlatformOneSecond * 5 : mDNSPlatformOneSecond / 2;
- const mDNSu8 numannounce = flapping ? (mDNSu8)1 : InitialAnnounceCount;
-
- // Use a small amount of randomness:
- // In the case of a network administrator turning on an Ethernet hub so that all the
- // connected machines establish link at exactly the same time, we don't want them all
- // to go and hit the network with identical queries at exactly the same moment.
- // We set a random delay of up to InitialQuestionInterval (1/3 second).
- // We must *never* set m->SuppressSending to more than that (or set it repeatedly in a way
- // that causes mDNSResponder to remain in a prolonged state of SuppressSending, because
- // suppressing packet sending for more than about 1/3 second can cause protocol correctness
- // to start to break down (e.g. we don't answer probes fast enough, and get name conflicts).
- // See <rdar://problem/4073853> mDNS: m->SuppressSending set too enthusiastically
- if (!m->SuppressSending) m->SuppressSending = m->timenow + (mDNSs32)mDNSRandom((mDNSu32)InitialQuestionInterval);
-
- if (flapping) LogMsg("mDNS_RegisterInterface: Frequent transitions for interface %s (%#a)", set->ifname, &set->ip);
-
- LogInfo("mDNS_RegisterInterface: %s (%#a) probedelay %d", set->ifname, &set->ip, probedelay);
- if (m->SuppressProbes == 0 ||
- m->SuppressProbes - NonZeroTime(m->timenow + probedelay) < 0)
- m->SuppressProbes = NonZeroTime(m->timenow + probedelay);
-
- // Include OWNER option in packets for 60 seconds after connecting to the network. Setting
- // it here also handles the wake up case as the network link comes UP after waking causing
- // us to reconnect to the network. If we do this as part of the wake up code, it is possible
- // that the network link comes UP after 60 seconds and we never set the OWNER option
- m->AnnounceOwner = NonZeroTime(m->timenow + 60 * mDNSPlatformOneSecond);
- LogInfo("mDNS_RegisterInterface: Setting AnnounceOwner");
-
- for (q = m->Questions; q; q=q->next) // Scan our list of questions
- if (mDNSOpaque16IsZero(q->TargetQID))
- if (!q->InterfaceID || q->InterfaceID == set->InterfaceID) // If non-specific Q, or Q on this specific interface,
- { // then reactivate this question
- // If flapping, delay between first and second queries is nine seconds instead of one second
- mDNSBool dodelay = flapping && (q->FlappingInterface1 == set->InterfaceID || q->FlappingInterface2 == set->InterfaceID);
- mDNSs32 initial = dodelay ? InitialQuestionInterval * QuestionIntervalStep2 : InitialQuestionInterval;
- mDNSs32 qdelay = dodelay ? mDNSPlatformOneSecond * 5 : 0;
- if (dodelay) LogInfo("No cache records expired for %##s (%s); okay to delay questions a little", q->qname.c, DNSTypeName(q->qtype));
-
- if (!q->ThisQInterval || q->ThisQInterval > initial)
- {
- q->ThisQInterval = initial;
- q->RequestUnicast = 2; // Set to 2 because is decremented once *before* we check it
- }
- q->LastQTime = m->timenow - q->ThisQInterval + qdelay;
- q->RecentAnswerPkts = 0;
- SetNextQueryTime(m,q);
- }
-
- // For all our non-specific authoritative resource records (and any dormant records specific to this interface)
- // we now need them to re-probe if necessary, and then re-announce.
- for (rr = m->ResourceRecords; rr; rr=rr->next)
- if (!AuthRecord_uDNS(rr))
- if (!rr->resrec.InterfaceID || rr->resrec.InterfaceID == set->InterfaceID)
- {
- if (rr->resrec.RecordType == kDNSRecordTypeVerified && !rr->DependentOn) rr->resrec.RecordType = kDNSRecordTypeUnique;
- rr->ProbeCount = DefaultProbeCountForRecordType(rr->resrec.RecordType);
- if (rr->AnnounceCount < numannounce) rr->AnnounceCount = numannounce;
- rr->SendNSECNow = mDNSNULL;
- InitializeLastAPTime(m, rr);
- }
- }
-
- RestartRecordGetZoneData(m);
-
- CheckSuppressUnusableQuestions(m);
-
- mDNS_UpdateAllowSleep(m);
-
- mDNS_Unlock(m);
- return(mStatus_NoError);
- }
+ // Assume this interface will be active now, unless we find a duplicate already in the list
+ set->InterfaceActive = mDNStrue;
+ set->IPv4Available = (mDNSu8)(set->ip.type == mDNSAddrType_IPv4 && set->McastTxRx);
+ set->IPv6Available = (mDNSu8)(set->ip.type == mDNSAddrType_IPv6 && set->McastTxRx);
+
+ InitializeNetWakeState(m, set);
+
+ // Scan list to see if this InterfaceID is already represented
+ while (*p)
+ {
+ if (*p == set)
+ {
+ LogMsg("mDNS_RegisterInterface: Error! Tried to register a NetworkInterfaceInfo that's already in the list");
+ mDNS_Unlock(m);
+ return(mStatus_AlreadyRegistered);
+ }
+
+ if ((*p)->InterfaceID == set->InterfaceID)
+ {
+ // This InterfaceID already represented by a different interface in the list, so mark this instance inactive for now
+ set->InterfaceActive = mDNSfalse;
+ if (set->ip.type == (*p)->ip.type) FirstOfType = mDNSfalse;
+ if (set->ip.type == mDNSAddrType_IPv4 && set->McastTxRx) (*p)->IPv4Available = mDNStrue;
+ if (set->ip.type == mDNSAddrType_IPv6 && set->McastTxRx) (*p)->IPv6Available = mDNStrue;
+ }
+
+ p=&(*p)->next;
+ }
+
+ set->next = mDNSNULL;
+ *p = set;
+
+ if (set->Advertise)
+ AdvertiseInterface(m, set);
+
+ LogInfo("mDNS_RegisterInterface: InterfaceID %d %s (%#a) %s",
+ (uint32_t)set->InterfaceID, set->ifname, &set->ip,
+ set->InterfaceActive ?
+ "not represented in list; marking active and retriggering queries" :
+ "already represented in list; marking inactive for now");
+
+ if (set->NetWake) mDNS_ActivateNetWake_internal(m, set);
+
+ // In early versions of OS X the IPv6 address remains on an interface even when the interface is turned off,
+ // giving the false impression that there's an active representative of this interface when there really isn't.
+ // Therefore, when registering an interface, we want to re-trigger our questions and re-probe our Resource Records,
+ // even if we believe that we previously had an active representative of this interface.
+ if (set->McastTxRx && (FirstOfType || set->InterfaceActive))
+ {
+ DNSQuestion *q;
+ // Normally, after an interface comes up, we pause half a second before beginning probing.
+ // This is to guard against cases where there's rapid interface changes, where we could be confused by
+ // seeing packets we ourselves sent just moments ago (perhaps when this interface had a different address)
+ // which are then echoed back after a short delay by some Ethernet switches and some 802.11 base stations.
+ // We don't want to do a probe, and then see a stale echo of an announcement we ourselves sent,
+ // and think it's a conflicting answer to our probe.
+ // In the case of a flapping interface, we pause for five seconds, and reduce the announcement count to one packet.
+ const mDNSs32 probedelay = flapping ? mDNSPlatformOneSecond * 5 : mDNSPlatformOneSecond / 2;
+ const mDNSu8 numannounce = flapping ? (mDNSu8)1 : InitialAnnounceCount;
+
+ // Use a small amount of randomness:
+ // In the case of a network administrator turning on an Ethernet hub so that all the
+ // connected machines establish link at exactly the same time, we don't want them all
+ // to go and hit the network with identical queries at exactly the same moment.
+ // We set a random delay of up to InitialQuestionInterval (1/3 second).
+ // We must *never* set m->SuppressSending to more than that (or set it repeatedly in a way
+ // that causes mDNSResponder to remain in a prolonged state of SuppressSending, because
+ // suppressing packet sending for more than about 1/3 second can cause protocol correctness
+ // to start to break down (e.g. we don't answer probes fast enough, and get name conflicts).
+ // See <rdar://problem/4073853> mDNS: m->SuppressSending set too enthusiastically
+ if (!m->SuppressSending) m->SuppressSending = m->timenow + (mDNSs32)mDNSRandom((mDNSu32)InitialQuestionInterval);
+
+ if (flapping)
+ {
+ LogMsg("mDNS_RegisterInterface: Frequent transitions for interface %s (%#a)", set->ifname, &set->ip);
+ m->mDNSStats.InterfaceUpFlap++;
+ }
+
+ LogInfo("mDNS_RegisterInterface: %s (%#a) probedelay %d", set->ifname, &set->ip, probedelay);
+ if (m->SuppressProbes == 0 ||
+ m->SuppressProbes - NonZeroTime(m->timenow + probedelay) < 0)
+ m->SuppressProbes = NonZeroTime(m->timenow + probedelay);
+
+ // Include OWNER option in packets for 60 seconds after connecting to the network. Setting
+ // it here also handles the wake up case as the network link comes UP after waking causing
+ // us to reconnect to the network. If we do this as part of the wake up code, it is possible
+ // that the network link comes UP after 60 seconds and we never set the OWNER option
+ m->AnnounceOwner = NonZeroTime(m->timenow + 60 * mDNSPlatformOneSecond);
+ LogInfo("mDNS_RegisterInterface: Setting AnnounceOwner");
+
+ m->mDNSStats.InterfaceUp++;
+ for (q = m->Questions; q; q=q->next) // Scan our list of questions
+ {
+ if (mDNSOpaque16IsZero(q->TargetQID))
+ {
+ if (!q->InterfaceID || q->InterfaceID == set->InterfaceID) // If non-specific Q, or Q on this specific interface,
+ { // then reactivate this question
+ // If flapping, delay between first and second queries is nine seconds instead of one second
+ mDNSBool dodelay = flapping && (q->FlappingInterface1 == set->InterfaceID || q->FlappingInterface2 == set->InterfaceID);
+ mDNSs32 initial = dodelay ? InitialQuestionInterval * QuestionIntervalStep2 : InitialQuestionInterval;
+ mDNSs32 qdelay = dodelay ? mDNSPlatformOneSecond * 5 : 0;
+ if (dodelay) LogInfo("No cache records expired for %##s (%s); okay to delay questions a little", q->qname.c, DNSTypeName(q->qtype));
+
+ if (!q->ThisQInterval || q->ThisQInterval > initial)
+ {
+ q->ThisQInterval = initial;
+
+#if mDNS_REQUEST_UNICAST_RESPONSE
+ q->RequestUnicast = SET_QU_IN_FIRST_FOUR_QUERIES;
+#else // mDNS_REQUEST_UNICAST_RESPONSE
+ q->RequestUnicast = SET_QU_IN_FIRST_QUERY;
+#endif // mDNS_REQUEST_UNICAST_RESPONSE
+
+ }
+ q->LastQTime = m->timenow - q->ThisQInterval + qdelay;
+ q->RecentAnswerPkts = 0;
+ // Change the salt
+ ReInitAnonInfo(&q->AnonInfo, &q->qname);
+ SetNextQueryTime(m,q);
+ }
+ }
+ }
+
+ // For all our non-specific authoritative resource records (and any dormant records specific to this interface)
+ // we now need them to re-probe if necessary, and then re-announce.
+ for (rr = m->ResourceRecords; rr; rr=rr->next)
+ {
+ if (!rr->resrec.InterfaceID || rr->resrec.InterfaceID == set->InterfaceID)
+ {
+ // Change the salt
+ ReInitAnonInfo(&rr->resrec.AnonInfo, rr->resrec.name);
+ mDNSCoreRestartRegistration(m, rr, numannounce);
+ }
+ }
+#if APPLE_OSX_mDNSResponder && !TARGET_OS_IPHONE
+ DNSSECProbe(m);
+#endif
+ }
+
+ RestartRecordGetZoneData(m);
+
+ mDNS_UpdateAllowSleep(m);
+
+ mDNS_Unlock(m);
+ return(mStatus_NoError);
+}
// Note: mDNS_DeregisterInterface calls mDNS_Deregister_internal which can call a user callback, which may change
// the record list and/or question list.
// Any code walking either list must use the CurrentQuestion and/or CurrentRecord mechanism to protect against this.
mDNSexport void mDNS_DeregisterInterface(mDNS *const m, NetworkInterfaceInfo *set, mDNSBool flapping)
- {
- NetworkInterfaceInfo **p = &m->HostInterfaces;
- mDNSBool revalidate = mDNSfalse;
-
- mDNS_Lock(m);
-
- // Find this record in our list
- while (*p && *p != set) p=&(*p)->next;
- if (!*p) { debugf("mDNS_DeregisterInterface: NetworkInterfaceInfo not found in list"); mDNS_Unlock(m); return; }
-
- mDNS_DeactivateNetWake_internal(m, set);
-
- // Unlink this record from our list
- *p = (*p)->next;
- set->next = mDNSNULL;
-
- if (!set->InterfaceActive)
- {
- // If this interface not the active member of its set, update the v4/v6Available flags for the active member
- NetworkInterfaceInfo *intf;
- for (intf = m->HostInterfaces; intf; intf = intf->next)
- if (intf->InterfaceActive && intf->InterfaceID == set->InterfaceID)
- UpdateInterfaceProtocols(m, intf);
- }
- else
- {
- NetworkInterfaceInfo *intf = FirstInterfaceForID(m, set->InterfaceID);
- if (intf)
- {
- LogInfo("mDNS_DeregisterInterface: Another representative of InterfaceID %p %s (%#a) exists;"
- " making it active", set->InterfaceID, set->ifname, &set->ip);
- if (intf->InterfaceActive)
- LogMsg("mDNS_DeregisterInterface: ERROR intf->InterfaceActive already set for %s (%#a)", set->ifname, &set->ip);
- intf->InterfaceActive = mDNStrue;
- UpdateInterfaceProtocols(m, intf);
-
- if (intf->NetWake) mDNS_ActivateNetWake_internal(m, intf);
-
- // See if another representative *of the same type* exists. If not, we mave have gone from
- // dual-stack to v6-only (or v4-only) so we need to reconfirm which records are still valid.
- for (intf = m->HostInterfaces; intf; intf = intf->next)
- if (intf->InterfaceID == set->InterfaceID && intf->ip.type == set->ip.type)
- break;
- if (!intf) revalidate = mDNStrue;
- }
- else
- {
- mDNSu32 slot;
- CacheGroup *cg;
- CacheRecord *rr;
- DNSQuestion *q;
- DNSServer *s;
-
- LogInfo("mDNS_DeregisterInterface: Last representative of InterfaceID %p %s (%#a) deregistered;"
- " marking questions etc. dormant", set->InterfaceID, set->ifname, &set->ip);
-
- if (set->McastTxRx && flapping)
- LogMsg("DeregisterInterface: Frequent transitions for interface %s (%#a)", set->ifname, &set->ip);
-
- // 1. Deactivate any questions specific to this interface, and tag appropriate questions
- // so that mDNS_RegisterInterface() knows how swiftly it needs to reactivate them
- for (q = m->Questions; q; q=q->next)
- {
- if (q->InterfaceID == set->InterfaceID) q->ThisQInterval = 0;
- if (!q->InterfaceID || q->InterfaceID == set->InterfaceID)
- {
- q->FlappingInterface2 = q->FlappingInterface1;
- q->FlappingInterface1 = set->InterfaceID; // Keep history of the last two interfaces to go away
- }
- }
-
- // 2. Flush any cache records received on this interface
- revalidate = mDNSfalse; // Don't revalidate if we're flushing the records
- FORALL_CACHERECORDS(slot, cg, rr)
- if (rr->resrec.InterfaceID == set->InterfaceID)
- {
- // If this interface is deemed flapping,
- // postpone deleting the cache records in case the interface comes back again
- if (set->McastTxRx && flapping)
- {
- // For a flapping interface we want these record to go away after 30 seconds
- mDNS_Reconfirm_internal(m, rr, kDefaultReconfirmTimeForFlappingInterface);
- // We set UnansweredQueries = MaxUnansweredQueries so we don't waste time doing any queries for them --
- // if the interface does come back, any relevant questions will be reactivated anyway
- rr->UnansweredQueries = MaxUnansweredQueries;
- }
- else
- mDNS_PurgeCacheResourceRecord(m, rr);
- }
-
- // 3. Any DNS servers specific to this interface are now unusable
- for (s = m->DNSServers; s; s = s->next)
- if (s->interface == set->InterfaceID)
- {
- s->interface = mDNSInterface_Any;
- s->teststate = DNSServer_Disabled;
- }
- }
- }
-
- // If we were advertising on this interface, deregister those address and reverse-lookup records now
- if (set->Advertise) DeadvertiseInterface(m, set);
-
- // If we have any cache records received on this interface that went away, then re-verify them.
- // In some versions of OS X the IPv6 address remains on an interface even when the interface is turned off,
- // giving the false impression that there's an active representative of this interface when there really isn't.
- // Don't need to do this when shutting down, because *all* interfaces are about to go away
- if (revalidate && !m->ShutdownTime)
- {
- mDNSu32 slot;
- CacheGroup *cg;
- CacheRecord *rr;
- FORALL_CACHERECORDS(slot, cg, rr)
- if (rr->resrec.InterfaceID == set->InterfaceID)
- mDNS_Reconfirm_internal(m, rr, kDefaultReconfirmTimeForFlappingInterface);
- }
-
- CheckSuppressUnusableQuestions(m);
-
- mDNS_UpdateAllowSleep(m);
-
- mDNS_Unlock(m);
- }
+{
+ NetworkInterfaceInfo **p = &m->HostInterfaces;
+ mDNSBool revalidate = mDNSfalse;
+
+ mDNS_Lock(m);
+
+ // Find this record in our list
+ while (*p && *p != set) p=&(*p)->next;
+ if (!*p) { debugf("mDNS_DeregisterInterface: NetworkInterfaceInfo not found in list"); mDNS_Unlock(m); return; }
+
+ mDNS_DeactivateNetWake_internal(m, set);
+
+ // Unlink this record from our list
+ *p = (*p)->next;
+ set->next = mDNSNULL;
+
+ if (!set->InterfaceActive)
+ {
+ // If this interface not the active member of its set, update the v4/v6Available flags for the active member
+ NetworkInterfaceInfo *intf;
+ for (intf = m->HostInterfaces; intf; intf = intf->next)
+ if (intf->InterfaceActive && intf->InterfaceID == set->InterfaceID)
+ UpdateInterfaceProtocols(m, intf);
+ }
+ else
+ {
+ NetworkInterfaceInfo *intf = FirstInterfaceForID(m, set->InterfaceID);
+ if (intf)
+ {
+ LogInfo("mDNS_DeregisterInterface: Another representative of InterfaceID %d %s (%#a) exists;"
+ " making it active", (uint32_t)set->InterfaceID, set->ifname, &set->ip);
+ if (intf->InterfaceActive)
+ LogMsg("mDNS_DeregisterInterface: ERROR intf->InterfaceActive already set for %s (%#a)", set->ifname, &set->ip);
+ intf->InterfaceActive = mDNStrue;
+ UpdateInterfaceProtocols(m, intf);
+
+ if (intf->NetWake) mDNS_ActivateNetWake_internal(m, intf);
+
+ // See if another representative *of the same type* exists. If not, we mave have gone from
+ // dual-stack to v6-only (or v4-only) so we need to reconfirm which records are still valid.
+ for (intf = m->HostInterfaces; intf; intf = intf->next)
+ if (intf->InterfaceID == set->InterfaceID && intf->ip.type == set->ip.type)
+ break;
+ if (!intf) revalidate = mDNStrue;
+ }
+ else
+ {
+ mDNSu32 slot;
+ CacheGroup *cg;
+ CacheRecord *rr;
+ DNSQuestion *q;
+
+ LogInfo("mDNS_DeregisterInterface: Last representative of InterfaceID %d %s (%#a) deregistered;"
+ " marking questions etc. dormant", (uint32_t)set->InterfaceID, set->ifname, &set->ip);
+
+ m->mDNSStats.InterfaceDown++;
+
+ if (set->McastTxRx && flapping)
+ {
+ LogMsg("DeregisterInterface: Frequent transitions for interface %s (%#a)", set->ifname, &set->ip);
+ m->mDNSStats.InterfaceDownFlap++;
+ }
+
+ // 1. Deactivate any questions specific to this interface, and tag appropriate questions
+ // so that mDNS_RegisterInterface() knows how swiftly it needs to reactivate them
+ for (q = m->Questions; q; q=q->next)
+ {
+ if (q->InterfaceID == set->InterfaceID) q->ThisQInterval = 0;
+ if (!q->InterfaceID || q->InterfaceID == set->InterfaceID)
+ {
+ q->FlappingInterface2 = q->FlappingInterface1;
+ q->FlappingInterface1 = set->InterfaceID; // Keep history of the last two interfaces to go away
+ }
+ }
+
+ // 2. Flush any cache records received on this interface
+ revalidate = mDNSfalse; // Don't revalidate if we're flushing the records
+ FORALL_CACHERECORDS(slot, cg, rr)
+ {
+ if (rr->resrec.InterfaceID == set->InterfaceID)
+ {
+ // If this interface is deemed flapping,
+ // postpone deleting the cache records in case the interface comes back again
+ if (set->McastTxRx && flapping)
+ {
+ // For a flapping interface we want these record to go away after 30 seconds
+ mDNS_Reconfirm_internal(m, rr, kDefaultReconfirmTimeForFlappingInterface);
+ // We set UnansweredQueries = MaxUnansweredQueries so we don't waste time doing any queries for them --
+ // if the interface does come back, any relevant questions will be reactivated anyway
+ rr->UnansweredQueries = MaxUnansweredQueries;
+ }
+ else
+ {
+ mDNS_PurgeCacheResourceRecord(m, rr);
+ }
+ }
+ }
+ }
+ }
+
+ // If we were advertising on this interface, deregister those address and reverse-lookup records now
+ if (set->Advertise) DeadvertiseInterface(m, set);
+
+ // If we have any cache records received on this interface that went away, then re-verify them.
+ // In some versions of OS X the IPv6 address remains on an interface even when the interface is turned off,
+ // giving the false impression that there's an active representative of this interface when there really isn't.
+ // Don't need to do this when shutting down, because *all* interfaces are about to go away
+ if (revalidate && !m->ShutdownTime)
+ {
+ mDNSu32 slot;
+ CacheGroup *cg;
+ CacheRecord *rr;
+ FORALL_CACHERECORDS(slot, cg, rr)
+ if (rr->resrec.InterfaceID == set->InterfaceID)
+ mDNS_Reconfirm_internal(m, rr, kDefaultReconfirmTimeForFlappingInterface);
+ }
+
+ mDNS_UpdateAllowSleep(m);
+
+ mDNS_Unlock(m);
+}
+
+mDNSlocal void SetAnonInfoSRS(ServiceRecordSet *sr, int NumSubTypes)
+{
+ int i, len;
+
+ if (!sr->AnonData)
+ return;
+
+ len = mDNSPlatformStrLen(sr->AnonData);
+ if (sr->RR_PTR.resrec.AnonInfo)
+ {
+ LogMsg("SetAnonInfoSRS: Freeing AnonInfo for PTR record %##s, should have been freed already", sr->RR_PTR.resrec.name->c);
+ FreeAnonInfo(sr->RR_PTR.resrec.AnonInfo);
+ }
+ sr->RR_PTR.resrec.AnonInfo = AllocateAnonInfo(sr->RR_PTR.resrec.name, sr->AnonData, len, mDNSNULL);
+ for (i=0; i<NumSubTypes; i++)
+ {
+ if (sr->SubTypes[i].resrec.AnonInfo)
+ {
+ LogMsg("SetAnonInfoSRS: Freeing AnonInfo for subtype record %##s, should have been freed already", sr->SubTypes[i].resrec.name->c);
+ FreeAnonInfo(sr->SubTypes[i].resrec.AnonInfo);
+ }
+ sr->SubTypes[i].resrec.AnonInfo = AllocateAnonInfo(sr->SubTypes[i].resrec.name, sr->AnonData, len, mDNSNULL);
+ }
+}
+
+mDNSlocal void ResetAnonInfoSRS(ServiceRecordSet *sr, int NumSubTypes)
+{
+ int i;
+
+ if (!sr->AnonData)
+ return;
+ if (sr->RR_PTR.resrec.AnonInfo)
+ {
+ FreeAnonInfo(sr->RR_PTR.resrec.AnonInfo);
+ sr->RR_PTR.resrec.AnonInfo = mDNSNULL;
+ }
+ for (i=0; i<NumSubTypes; i++)
+ {
+ if (sr->SubTypes[i].resrec.AnonInfo)
+ {
+ FreeAnonInfo(sr->SubTypes[i].resrec.AnonInfo);
+ sr->SubTypes[i].resrec.AnonInfo = mDNSNULL;
+ }
+ }
+}
mDNSlocal void ServiceCallback(mDNS *const m, AuthRecord *const rr, mStatus result)
- {
- ServiceRecordSet *sr = (ServiceRecordSet *)rr->RecordContext;
- (void)m; // Unused parameter
-
- #if MDNS_DEBUGMSGS
- {
- char *msg = "Unknown result";
- if (result == mStatus_NoError) msg = "Name Registered";
- else if (result == mStatus_NameConflict) msg = "Name Conflict";
- else if (result == mStatus_MemFree) msg = "Memory Free";
- debugf("ServiceCallback: %##s (%s) %s (%d)", rr->resrec.name->c, DNSTypeName(rr->resrec.rrtype), msg, result);
- }
- #endif
-
- // Only pass on the NoError acknowledgement for the SRV record (when it finishes probing)
- if (result == mStatus_NoError && rr != &sr->RR_SRV) return;
-
- // If we got a name conflict on either SRV or TXT, forcibly deregister this service, and record that we did that
- if (result == mStatus_NameConflict)
- {
- sr->Conflict = mDNStrue; // Record that this service set had a conflict
- mDNS_DeregisterService(m, sr); // Unlink the records from our list
- return;
- }
-
- if (result == mStatus_MemFree)
- {
- // If the SRV/TXT/PTR records, or the _services._dns-sd._udp record, or any of the subtype PTR records,
- // are still in the process of deregistering, don't pass on the NameConflict/MemFree message until
- // every record is finished cleaning up.
- mDNSu32 i;
- ExtraResourceRecord *e = sr->Extras;
-
- if (sr->RR_SRV.resrec.RecordType != kDNSRecordTypeUnregistered) return;
- if (sr->RR_TXT.resrec.RecordType != kDNSRecordTypeUnregistered) return;
- if (sr->RR_PTR.resrec.RecordType != kDNSRecordTypeUnregistered) return;
- if (sr->RR_ADV.resrec.RecordType != kDNSRecordTypeUnregistered) return;
- for (i=0; i<sr->NumSubTypes; i++) if (sr->SubTypes[i].resrec.RecordType != kDNSRecordTypeUnregistered) return;
-
- while (e)
- {
- if (e->r.resrec.RecordType != kDNSRecordTypeUnregistered) return;
- e = e->next;
- }
-
- // If this ServiceRecordSet was forcibly deregistered, and now its memory is ready for reuse,
- // then we can now report the NameConflict to the client
- if (sr->Conflict) result = mStatus_NameConflict;
-
- }
-
- LogInfo("ServiceCallback: All records %s for %##s", (result == mStatus_MemFree ? "Unregistered": "Registered"), sr->RR_PTR.resrec.name->c);
- // CAUTION: MUST NOT do anything more with sr after calling sr->Callback(), because the client's callback
- // function is allowed to do anything, including deregistering this service and freeing its memory.
- if (sr->ServiceCallback)
- sr->ServiceCallback(m, sr, result);
- }
+{
+ ServiceRecordSet *sr = (ServiceRecordSet *)rr->RecordContext;
+ (void)m; // Unused parameter
+
+ #if MDNS_DEBUGMSGS
+ {
+ char *msg = "Unknown result";
+ if (result == mStatus_NoError) msg = "Name Registered";
+ else if (result == mStatus_NameConflict) msg = "Name Conflict";
+ else if (result == mStatus_MemFree) msg = "Memory Free";
+ debugf("ServiceCallback: %##s (%s) %s (%d)", rr->resrec.name->c, DNSTypeName(rr->resrec.rrtype), msg, result);
+ }
+ #endif
+
+ // Only pass on the NoError acknowledgement for the SRV record (when it finishes probing)
+ if (result == mStatus_NoError && rr != &sr->RR_SRV) return;
+
+ // If we got a name conflict on either SRV or TXT, forcibly deregister this service, and record that we did that
+ if (result == mStatus_NameConflict)
+ {
+ sr->Conflict = mDNStrue; // Record that this service set had a conflict
+ mDNS_DeregisterService(m, sr); // Unlink the records from our list
+ return;
+ }
+
+ if (result == mStatus_MemFree)
+ {
+ // If the SRV/TXT/PTR records, or the _services._dns-sd._udp record, or any of the subtype PTR records,
+ // are still in the process of deregistering, don't pass on the NameConflict/MemFree message until
+ // every record is finished cleaning up.
+ mDNSu32 i;
+ ExtraResourceRecord *e = sr->Extras;
+
+ if (sr->RR_SRV.resrec.RecordType != kDNSRecordTypeUnregistered) return;
+ if (sr->RR_TXT.resrec.RecordType != kDNSRecordTypeUnregistered) return;
+ if (sr->RR_PTR.resrec.RecordType != kDNSRecordTypeUnregistered) return;
+ if (sr->RR_ADV.resrec.RecordType != kDNSRecordTypeUnregistered) return;
+ for (i=0; i<sr->NumSubTypes; i++) if (sr->SubTypes[i].resrec.RecordType != kDNSRecordTypeUnregistered) return;
+
+ while (e)
+ {
+ if (e->r.resrec.RecordType != kDNSRecordTypeUnregistered) return;
+ e = e->next;
+ }
+ ResetAnonInfoSRS(sr, sr->NumSubTypes);
+
+ // If this ServiceRecordSet was forcibly deregistered, and now its memory is ready for reuse,
+ // then we can now report the NameConflict to the client
+ if (sr->Conflict) result = mStatus_NameConflict;
+
+ }
+
+ LogInfo("ServiceCallback: All records %s for %##s", (result == mStatus_MemFree ? "Unregistered" : "Registered"), sr->RR_PTR.resrec.name->c);
+ // CAUTION: MUST NOT do anything more with sr after calling sr->Callback(), because the client's callback
+ // function is allowed to do anything, including deregistering this service and freeing its memory.
+ if (sr->ServiceCallback)
+ sr->ServiceCallback(m, sr, result);
+}
mDNSlocal void NSSCallback(mDNS *const m, AuthRecord *const rr, mStatus result)
- {
- ServiceRecordSet *sr = (ServiceRecordSet *)rr->RecordContext;
- if (sr->ServiceCallback)
- sr->ServiceCallback(m, sr, result);
- }
+{
+ ServiceRecordSet *sr = (ServiceRecordSet *)rr->RecordContext;
+ if (sr->ServiceCallback)
+ sr->ServiceCallback(m, sr, result);
+}
+
+
+mDNSlocal AuthRecType setAuthRecType(mDNSInterfaceID InterfaceID, mDNSu32 flags)
+{
+ AuthRecType artype;
+
+ if (InterfaceID == mDNSInterface_LocalOnly)
+ artype = AuthRecordLocalOnly;
+ else if (InterfaceID == mDNSInterface_P2P)
+ artype = AuthRecordP2P;
+ else if ((InterfaceID == mDNSInterface_Any) && (flags & coreFlagIncludeP2P)
+ && (flags & coreFlagIncludeAWDL))
+ artype = AuthRecordAnyIncludeAWDLandP2P;
+ else if ((InterfaceID == mDNSInterface_Any) && (flags & coreFlagIncludeP2P))
+ artype = AuthRecordAnyIncludeP2P;
+ else if ((InterfaceID == mDNSInterface_Any) && (flags & coreFlagIncludeAWDL))
+ artype = AuthRecordAnyIncludeAWDL;
+ else
+ artype = AuthRecordAny;
+
+ return artype;
+}
// Note:
// Name is first label of domain name (any dots in the name are actual dots, not label separators)
// then the default host name (m->MulticastHostname) is automatically used
// If the optional target host parameter is set, then the storage it points to must remain valid for the lifetime of the service registration
mDNSexport mStatus mDNS_RegisterService(mDNS *const m, ServiceRecordSet *sr,
- const domainlabel *const name, const domainname *const type, const domainname *const domain,
- const domainname *const host, mDNSIPPort port, const mDNSu8 txtinfo[], mDNSu16 txtlen,
- AuthRecord *SubTypes, mDNSu32 NumSubTypes,
- mDNSInterfaceID InterfaceID, mDNSServiceCallback Callback, void *Context, mDNSu32 flags)
- {
- mStatus err;
- mDNSu32 i;
- mDNSu32 hostTTL;
- AuthRecType artype;
- mDNSu8 recordType = (flags & regFlagKnownUnique) ? kDNSRecordTypeKnownUnique : kDNSRecordTypeUnique;
-
- sr->ServiceCallback = Callback;
- sr->ServiceContext = Context;
- sr->Conflict = mDNSfalse;
-
- sr->Extras = mDNSNULL;
- sr->NumSubTypes = NumSubTypes;
- sr->SubTypes = SubTypes;
-
- if (InterfaceID == mDNSInterface_LocalOnly)
- artype = AuthRecordLocalOnly;
- else if (InterfaceID == mDNSInterface_P2P)
- artype = AuthRecordP2P;
- else if ((InterfaceID == mDNSInterface_Any) && (flags & regFlagIncludeP2P))
- artype = AuthRecordAnyIncludeP2P;
- else
- artype = AuthRecordAny;
+ const domainlabel *const name, const domainname *const type, const domainname *const domain,
+ const domainname *const host, mDNSIPPort port, const mDNSu8 txtinfo[], mDNSu16 txtlen,
+ AuthRecord *SubTypes, mDNSu32 NumSubTypes,
+ mDNSInterfaceID InterfaceID, mDNSServiceCallback Callback, void *Context, mDNSu32 flags)
+{
+ mStatus err;
+ mDNSu32 i;
+ mDNSu32 hostTTL;
+ AuthRecType artype;
+ mDNSu8 recordType = (flags & coreFlagKnownUnique) ? kDNSRecordTypeKnownUnique : kDNSRecordTypeUnique;
+
+ sr->ServiceCallback = Callback;
+ sr->ServiceContext = Context;
+ sr->Conflict = mDNSfalse;
+
+ sr->Extras = mDNSNULL;
+ sr->NumSubTypes = NumSubTypes;
+ sr->SubTypes = SubTypes;
+ sr->flags = flags;
+
+ artype = setAuthRecType(InterfaceID, flags);
+
+ // Initialize the AuthRecord objects to sane values
+ // Need to initialize everything correctly *before* making the decision whether to do a RegisterNoSuchService and bail out
+ mDNS_SetupResourceRecord(&sr->RR_ADV, mDNSNULL, InterfaceID, kDNSType_PTR, kStandardTTL, kDNSRecordTypeAdvisory, artype, ServiceCallback, sr);
+ mDNS_SetupResourceRecord(&sr->RR_PTR, mDNSNULL, InterfaceID, kDNSType_PTR, kStandardTTL, kDNSRecordTypeShared, artype, ServiceCallback, sr);
+
+ if (flags & coreFlagWakeOnly)
+ {
+ sr->RR_PTR.AuthFlags = AuthFlagsWakeOnly;
+ }
+
+ if (SameDomainName(type, (const domainname *) "\x4" "_ubd" "\x4" "_tcp"))
+ hostTTL = kHostNameSmallTTL;
+ else
+ hostTTL = kHostNameTTL;
+
+ mDNS_SetupResourceRecord(&sr->RR_SRV, mDNSNULL, InterfaceID, kDNSType_SRV, hostTTL, recordType, artype, ServiceCallback, sr);
+ mDNS_SetupResourceRecord(&sr->RR_TXT, mDNSNULL, InterfaceID, kDNSType_TXT, kStandardTTL, kDNSRecordTypeUnique, artype, ServiceCallback, sr);
+
+ // If port number is zero, that means the client is really trying to do a RegisterNoSuchService
+ if (mDNSIPPortIsZero(port))
+ return(mDNS_RegisterNoSuchService(m, &sr->RR_SRV, name, type, domain, mDNSNULL, InterfaceID, NSSCallback, sr, flags));
+
+ // If the client is registering an oversized TXT record,
+ // it is the client's responsibility to alloate a ServiceRecordSet structure that is large enough for it
+ if (sr->RR_TXT.resrec.rdata->MaxRDLength < txtlen)
+ sr->RR_TXT.resrec.rdata->MaxRDLength = txtlen;
+
+ // Set up the record names
+ // For now we only create an advisory record for the main type, not for subtypes
+ // We need to gain some operational experience before we decide if there's a need to create them for subtypes too
+ if (ConstructServiceName(&sr->RR_ADV.namestorage, (const domainlabel*)"\x09_services", (const domainname*)"\x07_dns-sd\x04_udp", domain) == mDNSNULL)
+ return(mStatus_BadParamErr);
+ if (ConstructServiceName(&sr->RR_PTR.namestorage, mDNSNULL, type, domain) == mDNSNULL) return(mStatus_BadParamErr);
+ if (ConstructServiceName(&sr->RR_SRV.namestorage, name, type, domain) == mDNSNULL) return(mStatus_BadParamErr);
+ AssignDomainName(&sr->RR_TXT.namestorage, sr->RR_SRV.resrec.name);
+
+ // 1. Set up the ADV record rdata to advertise our service type
+ AssignDomainName(&sr->RR_ADV.resrec.rdata->u.name, sr->RR_PTR.resrec.name);
+
+ // 2. Set up the PTR record rdata to point to our service name
+ // We set up two additionals, so when a client asks for this PTR we automatically send the SRV and the TXT too
+ // Note: uDNS registration code assumes that Additional1 points to the SRV record
+ AssignDomainName(&sr->RR_PTR.resrec.rdata->u.name, sr->RR_SRV.resrec.name);
+ sr->RR_PTR.Additional1 = &sr->RR_SRV;
+ sr->RR_PTR.Additional2 = &sr->RR_TXT;
+
+ // 2a. Set up any subtype PTRs to point to our service name
+ // If the client is using subtypes, it is the client's responsibility to have
+ // already set the first label of the record name to the subtype being registered
+ for (i=0; i<NumSubTypes; i++)
+ {
+ domainname st;
+ AssignDomainName(&st, sr->SubTypes[i].resrec.name);
+ st.c[1+st.c[0]] = 0; // Only want the first label, not the whole FQDN (particularly for mDNS_RenameAndReregisterService())
+ AppendDomainName(&st, type);
+ mDNS_SetupResourceRecord(&sr->SubTypes[i], mDNSNULL, InterfaceID, kDNSType_PTR, kStandardTTL, kDNSRecordTypeShared, artype, ServiceCallback, sr);
+ if (ConstructServiceName(&sr->SubTypes[i].namestorage, mDNSNULL, &st, domain) == mDNSNULL) return(mStatus_BadParamErr);
+ AssignDomainName(&sr->SubTypes[i].resrec.rdata->u.name, &sr->RR_SRV.namestorage);
+ sr->SubTypes[i].Additional1 = &sr->RR_SRV;
+ sr->SubTypes[i].Additional2 = &sr->RR_TXT;
+ }
+
+ SetAnonInfoSRS(sr, NumSubTypes);
+
+ // 3. Set up the SRV record rdata.
+ sr->RR_SRV.resrec.rdata->u.srv.priority = 0;
+ sr->RR_SRV.resrec.rdata->u.srv.weight = 0;
+ sr->RR_SRV.resrec.rdata->u.srv.port = port;
+
+ // Setting AutoTarget tells DNS that the target of this SRV is to be automatically kept in sync with our host name
+ if (host && host->c[0]) AssignDomainName(&sr->RR_SRV.resrec.rdata->u.srv.target, host);
+ else { sr->RR_SRV.AutoTarget = Target_AutoHost; sr->RR_SRV.resrec.rdata->u.srv.target.c[0] = '\0'; }
+
+ // 4. Set up the TXT record rdata,
+ // and set DependentOn because we're depending on the SRV record to find and resolve conflicts for us
+ // Note: uDNS registration code assumes that DependentOn points to the SRV record
+ if (txtinfo == mDNSNULL) sr->RR_TXT.resrec.rdlength = 0;
+ else if (txtinfo != sr->RR_TXT.resrec.rdata->u.txt.c)
+ {
+ sr->RR_TXT.resrec.rdlength = txtlen;
+ if (sr->RR_TXT.resrec.rdlength > sr->RR_TXT.resrec.rdata->MaxRDLength) return(mStatus_BadParamErr);
+ mDNSPlatformMemCopy(sr->RR_TXT.resrec.rdata->u.txt.c, txtinfo, txtlen);
+ }
+ sr->RR_TXT.DependentOn = &sr->RR_SRV;
+
+ mDNS_Lock(m);
+ // It is important that we register SRV first. uDNS assumes that SRV is registered first so
+ // that if the SRV cannot find a target, rest of the records that belong to this service
+ // will not be activated.
+ err = mDNS_Register_internal(m, &sr->RR_SRV);
+ // If we can't register the SRV record due to errors, bail out. It has not been inserted in
+ // any list and hence no need to deregister. We could probably do similar checks for other
+ // records below and bail out. For now, this seems to be sufficient to address rdar://9304275
+ if (err)
+ {
+ mDNS_Unlock(m);
+ return err;
+ }
+ if (!err) err = mDNS_Register_internal(m, &sr->RR_TXT);
+ // We register the RR_PTR last, because we want to be sure that in the event of a forced call to
+ // mDNS_StartExit, the RR_PTR will be the last one to be forcibly deregistered, since that is what triggers
+ // the mStatus_MemFree callback to ServiceCallback, which in turn passes on the mStatus_MemFree back to
+ // the client callback, which is then at liberty to free the ServiceRecordSet memory at will. We need to
+ // make sure we've deregistered all our records and done any other necessary cleanup before that happens.
+ if (!err) err = mDNS_Register_internal(m, &sr->RR_ADV);
+ for (i=0; i<NumSubTypes; i++) if (!err) err = mDNS_Register_internal(m, &sr->SubTypes[i]);
+ if (!err) err = mDNS_Register_internal(m, &sr->RR_PTR);
+
+ mDNS_Unlock(m);
+
+ if (err) mDNS_DeregisterService(m, sr);
+ return(err);
+}
- // Initialize the AuthRecord objects to sane values
- // Need to initialize everything correctly *before* making the decision whether to do a RegisterNoSuchService and bail out
- mDNS_SetupResourceRecord(&sr->RR_ADV, mDNSNULL, InterfaceID, kDNSType_PTR, kStandardTTL, kDNSRecordTypeAdvisory, artype, ServiceCallback, sr);
- mDNS_SetupResourceRecord(&sr->RR_PTR, mDNSNULL, InterfaceID, kDNSType_PTR, kStandardTTL, kDNSRecordTypeShared, artype, ServiceCallback, sr);
+mDNSexport mStatus mDNS_AddRecordToService(mDNS *const m, ServiceRecordSet *sr,
+ ExtraResourceRecord *extra, RData *rdata, mDNSu32 ttl, mDNSu32 flags)
+{
+ ExtraResourceRecord **e;
+ mStatus status;
+ AuthRecType artype;
+ mDNSInterfaceID InterfaceID = sr->RR_PTR.resrec.InterfaceID;
- if (SameDomainName(type, (const domainname *) "\x4" "_ubd" "\x4" "_tcp"))
- hostTTL = kHostNameSmallTTL;
- else
- hostTTL = kHostNameTTL;
-
- mDNS_SetupResourceRecord(&sr->RR_SRV, mDNSNULL, InterfaceID, kDNSType_SRV, hostTTL, recordType, artype, ServiceCallback, sr);
- mDNS_SetupResourceRecord(&sr->RR_TXT, mDNSNULL, InterfaceID, kDNSType_TXT, kStandardTTL, kDNSRecordTypeUnique, artype, ServiceCallback, sr);
-
- // If port number is zero, that means the client is really trying to do a RegisterNoSuchService
- if (mDNSIPPortIsZero(port))
- return(mDNS_RegisterNoSuchService(m, &sr->RR_SRV, name, type, domain, mDNSNULL, InterfaceID, NSSCallback, sr, (flags & regFlagIncludeP2P)));
-
- // If the client is registering an oversized TXT record,
- // it is the client's responsibility to alloate a ServiceRecordSet structure that is large enough for it
- if (sr->RR_TXT.resrec.rdata->MaxRDLength < txtlen)
- sr->RR_TXT.resrec.rdata->MaxRDLength = txtlen;
-
- // Set up the record names
- // For now we only create an advisory record for the main type, not for subtypes
- // We need to gain some operational experience before we decide if there's a need to create them for subtypes too
- if (ConstructServiceName(&sr->RR_ADV.namestorage, (const domainlabel*)"\x09_services", (const domainname*)"\x07_dns-sd\x04_udp", domain) == mDNSNULL)
- return(mStatus_BadParamErr);
- if (ConstructServiceName(&sr->RR_PTR.namestorage, mDNSNULL, type, domain) == mDNSNULL) return(mStatus_BadParamErr);
- if (ConstructServiceName(&sr->RR_SRV.namestorage, name, type, domain) == mDNSNULL) return(mStatus_BadParamErr);
- AssignDomainName(&sr->RR_TXT.namestorage, sr->RR_SRV.resrec.name);
-
- // 1. Set up the ADV record rdata to advertise our service type
- AssignDomainName(&sr->RR_ADV.resrec.rdata->u.name, sr->RR_PTR.resrec.name);
-
- // 2. Set up the PTR record rdata to point to our service name
- // We set up two additionals, so when a client asks for this PTR we automatically send the SRV and the TXT too
- // Note: uDNS registration code assumes that Additional1 points to the SRV record
- AssignDomainName(&sr->RR_PTR.resrec.rdata->u.name, sr->RR_SRV.resrec.name);
- sr->RR_PTR.Additional1 = &sr->RR_SRV;
- sr->RR_PTR.Additional2 = &sr->RR_TXT;
-
- // 2a. Set up any subtype PTRs to point to our service name
- // If the client is using subtypes, it is the client's responsibility to have
- // already set the first label of the record name to the subtype being registered
- for (i=0; i<NumSubTypes; i++)
- {
- domainname st;
- AssignDomainName(&st, sr->SubTypes[i].resrec.name);
- st.c[1+st.c[0]] = 0; // Only want the first label, not the whole FQDN (particularly for mDNS_RenameAndReregisterService())
- AppendDomainName(&st, type);
- mDNS_SetupResourceRecord(&sr->SubTypes[i], mDNSNULL, InterfaceID, kDNSType_PTR, kStandardTTL, kDNSRecordTypeShared, artype, ServiceCallback, sr);
- if (ConstructServiceName(&sr->SubTypes[i].namestorage, mDNSNULL, &st, domain) == mDNSNULL) return(mStatus_BadParamErr);
- AssignDomainName(&sr->SubTypes[i].resrec.rdata->u.name, &sr->RR_SRV.namestorage);
- sr->SubTypes[i].Additional1 = &sr->RR_SRV;
- sr->SubTypes[i].Additional2 = &sr->RR_TXT;
- }
-
- // 3. Set up the SRV record rdata.
- sr->RR_SRV.resrec.rdata->u.srv.priority = 0;
- sr->RR_SRV.resrec.rdata->u.srv.weight = 0;
- sr->RR_SRV.resrec.rdata->u.srv.port = port;
-
- // Setting AutoTarget tells DNS that the target of this SRV is to be automatically kept in sync with our host name
- if (host && host->c[0]) AssignDomainName(&sr->RR_SRV.resrec.rdata->u.srv.target, host);
- else { sr->RR_SRV.AutoTarget = Target_AutoHost; sr->RR_SRV.resrec.rdata->u.srv.target.c[0] = '\0'; }
-
- // 4. Set up the TXT record rdata,
- // and set DependentOn because we're depending on the SRV record to find and resolve conflicts for us
- // Note: uDNS registration code assumes that DependentOn points to the SRV record
- if (txtinfo == mDNSNULL) sr->RR_TXT.resrec.rdlength = 0;
- else if (txtinfo != sr->RR_TXT.resrec.rdata->u.txt.c)
- {
- sr->RR_TXT.resrec.rdlength = txtlen;
- if (sr->RR_TXT.resrec.rdlength > sr->RR_TXT.resrec.rdata->MaxRDLength) return(mStatus_BadParamErr);
- mDNSPlatformMemCopy(sr->RR_TXT.resrec.rdata->u.txt.c, txtinfo, txtlen);
- }
- sr->RR_TXT.DependentOn = &sr->RR_SRV;
-
- mDNS_Lock(m);
- // It is important that we register SRV first. uDNS assumes that SRV is registered first so
- // that if the SRV cannot find a target, rest of the records that belong to this service
- // will not be activated.
- err = mDNS_Register_internal(m, &sr->RR_SRV);
- // If we can't register the SRV record due to errors, bail out. It has not been inserted in
- // any list and hence no need to deregister. We could probably do similar checks for other
- // records below and bail out. For now, this seems to be sufficient to address rdar://9304275
- if (err)
- {
- mDNS_Unlock(m);
- return err;
- }
- if (!err) err = mDNS_Register_internal(m, &sr->RR_TXT);
- // We register the RR_PTR last, because we want to be sure that in the event of a forced call to
- // mDNS_StartExit, the RR_PTR will be the last one to be forcibly deregistered, since that is what triggers
- // the mStatus_MemFree callback to ServiceCallback, which in turn passes on the mStatus_MemFree back to
- // the client callback, which is then at liberty to free the ServiceRecordSet memory at will. We need to
- // make sure we've deregistered all our records and done any other necessary cleanup before that happens.
- if (!err) err = mDNS_Register_internal(m, &sr->RR_ADV);
- for (i=0; i<NumSubTypes; i++) if (!err) err = mDNS_Register_internal(m, &sr->SubTypes[i]);
- if (!err) err = mDNS_Register_internal(m, &sr->RR_PTR);
-
- mDNS_Unlock(m);
-
- if (err) mDNS_DeregisterService(m, sr);
- return(err);
- }
+ artype = setAuthRecType(InterfaceID, flags);
-mDNSexport mStatus mDNS_AddRecordToService(mDNS *const m, ServiceRecordSet *sr,
- ExtraResourceRecord *extra, RData *rdata, mDNSu32 ttl, mDNSu32 includeP2P)
- {
- ExtraResourceRecord **e;
- mStatus status;
- AuthRecType artype;
- mDNSInterfaceID InterfaceID = sr->RR_PTR.resrec.InterfaceID;
-
- if (InterfaceID == mDNSInterface_LocalOnly)
- artype = AuthRecordLocalOnly;
- if (InterfaceID == mDNSInterface_P2P)
- artype = AuthRecordP2P;
- else if ((InterfaceID == mDNSInterface_Any) && includeP2P)
- artype = AuthRecordAnyIncludeP2P;
- else
- artype = AuthRecordAny;
+ extra->next = mDNSNULL;
+ mDNS_SetupResourceRecord(&extra->r, rdata, sr->RR_PTR.resrec.InterfaceID,
+ extra->r.resrec.rrtype, ttl, kDNSRecordTypeUnique, artype, ServiceCallback, sr);
+ AssignDomainName(&extra->r.namestorage, sr->RR_SRV.resrec.name);
- extra->next = mDNSNULL;
- mDNS_SetupResourceRecord(&extra->r, rdata, sr->RR_PTR.resrec.InterfaceID,
- extra->r.resrec.rrtype, ttl, kDNSRecordTypeUnique, artype, ServiceCallback, sr);
- AssignDomainName(&extra->r.namestorage, sr->RR_SRV.resrec.name);
-
- mDNS_Lock(m);
- e = &sr->Extras;
- while (*e) e = &(*e)->next;
+ mDNS_Lock(m);
+ e = &sr->Extras;
+ while (*e) e = &(*e)->next;
- if (ttl == 0) ttl = kStandardTTL;
+ if (ttl == 0) ttl = kStandardTTL;
- extra->r.DependentOn = &sr->RR_SRV;
+ extra->r.DependentOn = &sr->RR_SRV;
- debugf("mDNS_AddRecordToService adding record to %##s %s %d",
- extra->r.resrec.name->c, DNSTypeName(extra->r.resrec.rrtype), extra->r.resrec.rdlength);
+ debugf("mDNS_AddRecordToService adding record to %##s %s %d",
+ extra->r.resrec.name->c, DNSTypeName(extra->r.resrec.rrtype), extra->r.resrec.rdlength);
- status = mDNS_Register_internal(m, &extra->r);
- if (status == mStatus_NoError) *e = extra;
+ status = mDNS_Register_internal(m, &extra->r);
+ if (status == mStatus_NoError) *e = extra;
- mDNS_Unlock(m);
- return(status);
- }
+ mDNS_Unlock(m);
+ return(status);
+}
mDNSexport mStatus mDNS_RemoveRecordFromService(mDNS *const m, ServiceRecordSet *sr, ExtraResourceRecord *extra,
- mDNSRecordCallback MemFreeCallback, void *Context)
- {
- ExtraResourceRecord **e;
- mStatus status;
-
- mDNS_Lock(m);
- e = &sr->Extras;
- while (*e && *e != extra) e = &(*e)->next;
- if (!*e)
- {
- debugf("mDNS_RemoveRecordFromService failed to remove record from %##s", extra->r.resrec.name->c);
- status = mStatus_BadReferenceErr;
- }
- else
- {
- debugf("mDNS_RemoveRecordFromService removing record from %##s", extra->r.resrec.name->c);
- extra->r.RecordCallback = MemFreeCallback;
- extra->r.RecordContext = Context;
- *e = (*e)->next;
- status = mDNS_Deregister_internal(m, &extra->r, mDNS_Dereg_normal);
- }
- mDNS_Unlock(m);
- return(status);
- }
+ mDNSRecordCallback MemFreeCallback, void *Context)
+{
+ ExtraResourceRecord **e;
+ mStatus status;
+
+ mDNS_Lock(m);
+ e = &sr->Extras;
+ while (*e && *e != extra) e = &(*e)->next;
+ if (!*e)
+ {
+ debugf("mDNS_RemoveRecordFromService failed to remove record from %##s", extra->r.resrec.name->c);
+ status = mStatus_BadReferenceErr;
+ }
+ else
+ {
+ debugf("mDNS_RemoveRecordFromService removing record from %##s", extra->r.resrec.name->c);
+ extra->r.RecordCallback = MemFreeCallback;
+ extra->r.RecordContext = Context;
+ *e = (*e)->next;
+ status = mDNS_Deregister_internal(m, &extra->r, mDNS_Dereg_normal);
+ }
+ mDNS_Unlock(m);
+ return(status);
+}
mDNSexport mStatus mDNS_RenameAndReregisterService(mDNS *const m, ServiceRecordSet *const sr, const domainlabel *newname)
- {
- // Note: Don't need to use mDNS_Lock(m) here, because this code is just using public routines
- // mDNS_RegisterService() and mDNS_AddRecordToService(), which do the right locking internally.
- domainlabel name1, name2;
- domainname type, domain;
- const domainname *host = sr->RR_SRV.AutoTarget ? mDNSNULL : &sr->RR_SRV.resrec.rdata->u.srv.target;
- ExtraResourceRecord *extras = sr->Extras;
- mStatus err;
-
- DeconstructServiceName(sr->RR_SRV.resrec.name, &name1, &type, &domain);
- if (!newname)
- {
- name2 = name1;
- IncrementLabelSuffix(&name2, mDNStrue);
- newname = &name2;
- }
-
- if (SameDomainName(&domain, &localdomain))
- debugf("%##s service renamed from \"%#s\" to \"%#s\"", type.c, name1.c, newname->c);
- else debugf("%##s service (domain %##s) renamed from \"%#s\" to \"%#s\"",type.c, domain.c, name1.c, newname->c);
-
- err = mDNS_RegisterService(m, sr, newname, &type, &domain,
- host, sr->RR_SRV.resrec.rdata->u.srv.port, sr->RR_TXT.resrec.rdata->u.txt.c, sr->RR_TXT.resrec.rdlength,
- sr->SubTypes, sr->NumSubTypes,
- sr->RR_PTR.resrec.InterfaceID, sr->ServiceCallback, sr->ServiceContext, 0);
-
- // mDNS_RegisterService() just reset sr->Extras to NULL.
- // Fortunately we already grabbed ourselves a copy of this pointer (above), so we can now run
- // through the old list of extra records, and re-add them to our freshly created service registration
- while (!err && extras)
- {
- ExtraResourceRecord *e = extras;
- extras = extras->next;
- err = mDNS_AddRecordToService(m, sr, e, e->r.resrec.rdata, e->r.resrec.rroriginalttl, 0);
- }
-
- return(err);
- }
+{
+ // Note: Don't need to use mDNS_Lock(m) here, because this code is just using public routines
+ // mDNS_RegisterService() and mDNS_AddRecordToService(), which do the right locking internally.
+ domainlabel name1, name2;
+ domainname type, domain;
+ const domainname *host = sr->RR_SRV.AutoTarget ? mDNSNULL : &sr->RR_SRV.resrec.rdata->u.srv.target;
+ ExtraResourceRecord *extras = sr->Extras;
+ mStatus err;
+
+ DeconstructServiceName(sr->RR_SRV.resrec.name, &name1, &type, &domain);
+ if (!newname)
+ {
+ name2 = name1;
+ IncrementLabelSuffix(&name2, mDNStrue);
+ newname = &name2;
+ }
+
+ if (SameDomainName(&domain, &localdomain))
+ debugf("%##s service renamed from \"%#s\" to \"%#s\"", type.c, name1.c, newname->c);
+ else debugf("%##s service (domain %##s) renamed from \"%#s\" to \"%#s\"",type.c, domain.c, name1.c, newname->c);
+
+ err = mDNS_RegisterService(m, sr, newname, &type, &domain,
+ host, sr->RR_SRV.resrec.rdata->u.srv.port, sr->RR_TXT.resrec.rdata->u.txt.c, sr->RR_TXT.resrec.rdlength,
+ sr->SubTypes, sr->NumSubTypes,
+ sr->RR_PTR.resrec.InterfaceID, sr->ServiceCallback, sr->ServiceContext, sr->flags);
+
+ // mDNS_RegisterService() just reset sr->Extras to NULL.
+ // Fortunately we already grabbed ourselves a copy of this pointer (above), so we can now run
+ // through the old list of extra records, and re-add them to our freshly created service registration
+ while (!err && extras)
+ {
+ ExtraResourceRecord *e = extras;
+ extras = extras->next;
+ err = mDNS_AddRecordToService(m, sr, e, e->r.resrec.rdata, e->r.resrec.rroriginalttl, 0);
+ }
+
+ return(err);
+}
// Note: mDNS_DeregisterService calls mDNS_Deregister_internal which can call a user callback,
// which may change the record list and/or question list.
// Any code walking either list must use the CurrentQuestion and/or CurrentRecord mechanism to protect against this.
mDNSexport mStatus mDNS_DeregisterService_drt(mDNS *const m, ServiceRecordSet *sr, mDNS_Dereg_type drt)
- {
- // If port number is zero, that means this was actually registered using mDNS_RegisterNoSuchService()
- if (mDNSIPPortIsZero(sr->RR_SRV.resrec.rdata->u.srv.port)) return(mDNS_DeregisterNoSuchService(m, &sr->RR_SRV));
-
- if (sr->RR_PTR.resrec.RecordType == kDNSRecordTypeUnregistered)
- {
- debugf("Service set for %##s already deregistered", sr->RR_SRV.resrec.name->c);
- return(mStatus_BadReferenceErr);
- }
- else if (sr->RR_PTR.resrec.RecordType == kDNSRecordTypeDeregistering)
- {
- LogInfo("Service set for %##s already in the process of deregistering", sr->RR_SRV.resrec.name->c);
- // Avoid race condition:
- // If a service gets a conflict, then we set the Conflict flag to tell us to generate
- // an mStatus_NameConflict message when we get the mStatus_MemFree for our PTR record.
- // If the client happens to deregister the service in the middle of that process, then
- // we clear the flag back to the normal state, so that we deliver a plain mStatus_MemFree
- // instead of incorrectly promoting it to mStatus_NameConflict.
- // This race condition is exposed particularly when the conformance test generates
- // a whole batch of simultaneous conflicts across a range of services all advertised
- // using the same system default name, and if we don't take this precaution then
- // we end up incrementing m->nicelabel multiple times instead of just once.
- // <rdar://problem/4060169> Bug when auto-renaming Computer Name after name collision
- sr->Conflict = mDNSfalse;
- return(mStatus_NoError);
- }
- else
- {
- mDNSu32 i;
- mStatus status;
- ExtraResourceRecord *e;
- mDNS_Lock(m);
- e = sr->Extras;
-
- // We use mDNS_Dereg_repeat because, in the event of a collision, some or all of the
- // SRV, TXT, or Extra records could have already been automatically deregistered, and that's okay
- mDNS_Deregister_internal(m, &sr->RR_SRV, mDNS_Dereg_repeat);
- mDNS_Deregister_internal(m, &sr->RR_TXT, mDNS_Dereg_repeat);
-
- mDNS_Deregister_internal(m, &sr->RR_ADV, drt);
-
- // We deregister all of the extra records, but we leave the sr->Extras list intact
- // in case the client wants to do a RenameAndReregister and reinstate the registration
- while (e)
- {
- mDNS_Deregister_internal(m, &e->r, mDNS_Dereg_repeat);
- e = e->next;
- }
-
- for (i=0; i<sr->NumSubTypes; i++)
- mDNS_Deregister_internal(m, &sr->SubTypes[i], drt);
-
- status = mDNS_Deregister_internal(m, &sr->RR_PTR, drt);
- mDNS_Unlock(m);
- return(status);
- }
- }
+{
+ // If port number is zero, that means this was actually registered using mDNS_RegisterNoSuchService()
+ if (mDNSIPPortIsZero(sr->RR_SRV.resrec.rdata->u.srv.port)) return(mDNS_DeregisterNoSuchService(m, &sr->RR_SRV));
+
+ if (sr->RR_PTR.resrec.RecordType == kDNSRecordTypeUnregistered)
+ {
+ debugf("Service set for %##s already deregistered", sr->RR_SRV.resrec.name->c);
+ return(mStatus_BadReferenceErr);
+ }
+ else if (sr->RR_PTR.resrec.RecordType == kDNSRecordTypeDeregistering)
+ {
+ LogInfo("Service set for %##s already in the process of deregistering", sr->RR_SRV.resrec.name->c);
+ // Avoid race condition:
+ // If a service gets a conflict, then we set the Conflict flag to tell us to generate
+ // an mStatus_NameConflict message when we get the mStatus_MemFree for our PTR record.
+ // If the client happens to deregister the service in the middle of that process, then
+ // we clear the flag back to the normal state, so that we deliver a plain mStatus_MemFree
+ // instead of incorrectly promoting it to mStatus_NameConflict.
+ // This race condition is exposed particularly when the conformance test generates
+ // a whole batch of simultaneous conflicts across a range of services all advertised
+ // using the same system default name, and if we don't take this precaution then
+ // we end up incrementing m->nicelabel multiple times instead of just once.
+ // <rdar://problem/4060169> Bug when auto-renaming Computer Name after name collision
+ sr->Conflict = mDNSfalse;
+ return(mStatus_NoError);
+ }
+ else
+ {
+ mDNSu32 i;
+ mStatus status;
+ ExtraResourceRecord *e;
+ mDNS_Lock(m);
+ e = sr->Extras;
+
+ // We use mDNS_Dereg_repeat because, in the event of a collision, some or all of the
+ // SRV, TXT, or Extra records could have already been automatically deregistered, and that's okay
+ mDNS_Deregister_internal(m, &sr->RR_SRV, mDNS_Dereg_repeat);
+ mDNS_Deregister_internal(m, &sr->RR_TXT, mDNS_Dereg_repeat);
+
+ mDNS_Deregister_internal(m, &sr->RR_ADV, drt);
+
+ // We deregister all of the extra records, but we leave the sr->Extras list intact
+ // in case the client wants to do a RenameAndReregister and reinstate the registration
+ while (e)
+ {
+ mDNS_Deregister_internal(m, &e->r, mDNS_Dereg_repeat);
+ e = e->next;
+ }
+
+ for (i=0; i<sr->NumSubTypes; i++)
+ mDNS_Deregister_internal(m, &sr->SubTypes[i], drt);
+
+ status = mDNS_Deregister_internal(m, &sr->RR_PTR, drt);
+ mDNS_Unlock(m);
+ return(status);
+ }
+}
// Create a registration that asserts that no such service exists with this name.
// This can be useful where there is a given function is available through several protocols.
// "LPR" service called "Stuart's Printer". Without this precaution, another printer than offers only "LPR" printing
// could inadvertently advertise its service under the same name "Stuart's Printer", which might be confusing for users.
mDNSexport mStatus mDNS_RegisterNoSuchService(mDNS *const m, AuthRecord *const rr,
- const domainlabel *const name, const domainname *const type, const domainname *const domain,
- const domainname *const host,
- const mDNSInterfaceID InterfaceID, mDNSRecordCallback Callback, void *Context, mDNSBool includeP2P)
- {
- AuthRecType artype;
-
- if (InterfaceID == mDNSInterface_LocalOnly)
- artype = AuthRecordLocalOnly;
- else if (InterfaceID == mDNSInterface_P2P)
- artype = AuthRecordP2P;
- else if ((InterfaceID == mDNSInterface_Any) && includeP2P)
- artype = AuthRecordAnyIncludeP2P;
- else
- artype = AuthRecordAny;
-
- mDNS_SetupResourceRecord(rr, mDNSNULL, InterfaceID, kDNSType_SRV, kHostNameTTL, kDNSRecordTypeUnique, artype, Callback, Context);
- if (ConstructServiceName(&rr->namestorage, name, type, domain) == mDNSNULL) return(mStatus_BadParamErr);
- rr->resrec.rdata->u.srv.priority = 0;
- rr->resrec.rdata->u.srv.weight = 0;
- rr->resrec.rdata->u.srv.port = zeroIPPort;
- if (host && host->c[0]) AssignDomainName(&rr->resrec.rdata->u.srv.target, host);
- else rr->AutoTarget = Target_AutoHost;
- return(mDNS_Register(m, rr));
- }
+ const domainlabel *const name, const domainname *const type, const domainname *const domain,
+ const domainname *const host,
+ const mDNSInterfaceID InterfaceID, mDNSRecordCallback Callback, void *Context, mDNSu32 flags)
+{
+ AuthRecType artype;
+
+ artype = setAuthRecType(InterfaceID, flags);
+
+ mDNS_SetupResourceRecord(rr, mDNSNULL, InterfaceID, kDNSType_SRV, kHostNameTTL, kDNSRecordTypeUnique, artype, Callback, Context);
+ if (ConstructServiceName(&rr->namestorage, name, type, domain) == mDNSNULL) return(mStatus_BadParamErr);
+ rr->resrec.rdata->u.srv.priority = 0;
+ rr->resrec.rdata->u.srv.weight = 0;
+ rr->resrec.rdata->u.srv.port = zeroIPPort;
+ if (host && host->c[0]) AssignDomainName(&rr->resrec.rdata->u.srv.target, host);
+ else rr->AutoTarget = Target_AutoHost;
+ return(mDNS_Register(m, rr));
+}
mDNSexport mStatus mDNS_AdvertiseDomains(mDNS *const m, AuthRecord *rr,
- mDNS_DomainType DomainType, const mDNSInterfaceID InterfaceID, char *domname)
- {
- AuthRecType artype;
-
- if (InterfaceID == mDNSInterface_LocalOnly)
- artype = AuthRecordLocalOnly;
- else if (InterfaceID == mDNSInterface_P2P)
- artype = AuthRecordP2P;
- else
- artype = AuthRecordAny;
- mDNS_SetupResourceRecord(rr, mDNSNULL, InterfaceID, kDNSType_PTR, kStandardTTL, kDNSRecordTypeShared, artype, mDNSNULL, mDNSNULL);
- if (!MakeDomainNameFromDNSNameString(&rr->namestorage, mDNS_DomainTypeNames[DomainType])) return(mStatus_BadParamErr);
- if (!MakeDomainNameFromDNSNameString(&rr->resrec.rdata->u.name, domname)) return(mStatus_BadParamErr);
- return(mDNS_Register(m, rr));
- }
-
+ mDNS_DomainType DomainType, const mDNSInterfaceID InterfaceID, char *domname)
+{
+ AuthRecType artype;
+
+ if (InterfaceID == mDNSInterface_LocalOnly)
+ artype = AuthRecordLocalOnly;
+ else if (InterfaceID == mDNSInterface_P2P)
+ artype = AuthRecordP2P;
+ else
+ artype = AuthRecordAny;
+ mDNS_SetupResourceRecord(rr, mDNSNULL, InterfaceID, kDNSType_PTR, kStandardTTL, kDNSRecordTypeShared, artype, mDNSNULL, mDNSNULL);
+ if (!MakeDomainNameFromDNSNameString(&rr->namestorage, mDNS_DomainTypeNames[DomainType])) return(mStatus_BadParamErr);
+ if (!MakeDomainNameFromDNSNameString(&rr->resrec.rdata->u.name, domname)) return(mStatus_BadParamErr);
+ return(mDNS_Register(m, rr));
+}
+
mDNSlocal mDNSBool mDNS_IdUsedInResourceRecordsList(mDNS * const m, mDNSOpaque16 id)
- {
- AuthRecord *r;
- for (r = m->ResourceRecords; r; r=r->next) if (mDNSSameOpaque16(id, r->updateid)) return mDNStrue;
- return mDNSfalse;
- }
-
+{
+ AuthRecord *r;
+ for (r = m->ResourceRecords; r; r=r->next) if (mDNSSameOpaque16(id, r->updateid)) return mDNStrue;
+ return mDNSfalse;
+}
+
mDNSlocal mDNSBool mDNS_IdUsedInQuestionsList(mDNS * const m, mDNSOpaque16 id)
- {
- DNSQuestion *q;
- for (q = m->Questions; q; q=q->next) if (mDNSSameOpaque16(id, q->TargetQID)) return mDNStrue;
- return mDNSfalse;
- }
-
+{
+ DNSQuestion *q;
+ for (q = m->Questions; q; q=q->next) if (mDNSSameOpaque16(id, q->TargetQID)) return mDNStrue;
+ return mDNSfalse;
+}
+
mDNSexport mDNSOpaque16 mDNS_NewMessageID(mDNS * const m)
- {
- mDNSOpaque16 id;
- int i;
+{
+ mDNSOpaque16 id;
+ int i;
- for (i=0; i<10; i++)
- {
- id = mDNSOpaque16fromIntVal(1 + (mDNSu16)mDNSRandom(0xFFFE));
- if (!mDNS_IdUsedInResourceRecordsList(m, id) && !mDNS_IdUsedInQuestionsList(m, id)) break;
- }
-
- debugf("mDNS_NewMessageID: %5d", mDNSVal16(id));
+ for (i=0; i<10; i++)
+ {
+ id = mDNSOpaque16fromIntVal(1 + (mDNSu16)mDNSRandom(0xFFFE));
+ if (!mDNS_IdUsedInResourceRecordsList(m, id) && !mDNS_IdUsedInQuestionsList(m, id)) break;
+ }
+
+ debugf("mDNS_NewMessageID: %5d", mDNSVal16(id));
- return id;
- }
+ return id;
+}
// ***************************************************************************
#if COMPILER_LIKES_PRAGMA_MARK
#endif
mDNSlocal void RestartARPProbing(mDNS *const m, AuthRecord *const rr)
- {
- // If we see an ARP from a machine we think is sleeping, then either
- // (i) the machine has woken, or
- // (ii) it's just a stray old packet from before the machine slept
- // To handle the second case, we reset ProbeCount, so we'll suppress our own answers for a while, to avoid
- // generating ARP conflicts with a waking machine, and set rr->LastAPTime so we'll start probing again in 10 seconds.
- // If the machine has just woken then we'll discard our records when we see the first new mDNS probe from that machine.
- // If it was a stray old packet, then after 10 seconds we'll probe again and then start answering ARPs again. In this case we *do*
- // need to send new ARP Announcements, because the owner's ARP broadcasts will have updated neighboring ARP caches, so we need to
- // re-assert our (temporary) ownership of that IP address in order to receive subsequent packets addressed to that IPv4 address.
-
- rr->resrec.RecordType = kDNSRecordTypeUnique;
- rr->ProbeCount = DefaultProbeCountForTypeUnique;
-
- // If we haven't started announcing yet (and we're not already in ten-second-delay mode) the machine is probably
- // still going to sleep, so we just reset rr->ProbeCount so we'll continue probing until it stops responding.
- // If we *have* started announcing, the machine is probably in the process of waking back up, so in that case
- // we're more cautious and we wait ten seconds before probing it again. We do this because while waking from
- // sleep, some network interfaces tend to lose or delay inbound packets, and without this delay, if the waking machine
- // didn't answer our three probes within three seconds then we'd announce and cause it an unnecessary address conflict.
- if (rr->AnnounceCount == InitialAnnounceCount && m->timenow - rr->LastAPTime >= 0)
- InitializeLastAPTime(m, rr);
- else
- {
- rr->AnnounceCount = InitialAnnounceCount;
- rr->ThisAPInterval = mDNSPlatformOneSecond;
- rr->LastAPTime = m->timenow + mDNSPlatformOneSecond * 9; // Send first packet at rr->LastAPTime + rr->ThisAPInterval, i.e. 10 seconds from now
- SetNextAnnounceProbeTime(m, rr);
- }
- }
+{
+ // If we see an ARP from a machine we think is sleeping, then either
+ // (i) the machine has woken, or
+ // (ii) it's just a stray old packet from before the machine slept
+ // To handle the second case, we reset ProbeCount, so we'll suppress our own answers for a while, to avoid
+ // generating ARP conflicts with a waking machine, and set rr->LastAPTime so we'll start probing again in 10 seconds.
+ // If the machine has just woken then we'll discard our records when we see the first new mDNS probe from that machine.
+ // If it was a stray old packet, then after 10 seconds we'll probe again and then start answering ARPs again. In this case we *do*
+ // need to send new ARP Announcements, because the owner's ARP broadcasts will have updated neighboring ARP caches, so we need to
+ // re-assert our (temporary) ownership of that IP address in order to receive subsequent packets addressed to that IPv4 address.
+
+ rr->resrec.RecordType = kDNSRecordTypeUnique;
+ rr->ProbeCount = DefaultProbeCountForTypeUnique;
+ rr->ProbeRestartCount++;
+
+ // If we haven't started announcing yet (and we're not already in ten-second-delay mode) the machine is probably
+ // still going to sleep, so we just reset rr->ProbeCount so we'll continue probing until it stops responding.
+ // If we *have* started announcing, the machine is probably in the process of waking back up, so in that case
+ // we're more cautious and we wait ten seconds before probing it again. We do this because while waking from
+ // sleep, some network interfaces tend to lose or delay inbound packets, and without this delay, if the waking machine
+ // didn't answer our three probes within three seconds then we'd announce and cause it an unnecessary address conflict.
+ if (rr->AnnounceCount == InitialAnnounceCount && m->timenow - rr->LastAPTime >= 0)
+ InitializeLastAPTime(m, rr);
+ else
+ {
+ rr->AnnounceCount = InitialAnnounceCount;
+ rr->ThisAPInterval = mDNSPlatformOneSecond;
+ rr->LastAPTime = m->timenow + mDNSPlatformOneSecond * 9; // Send first packet at rr->LastAPTime + rr->ThisAPInterval, i.e. 10 seconds from now
+ SetNextAnnounceProbeTime(m, rr);
+ }
+}
mDNSlocal void mDNSCoreReceiveRawARP(mDNS *const m, const ARP_EthIP *const arp, const mDNSInterfaceID InterfaceID)
- {
- static const mDNSOpaque16 ARP_op_request = { { 0, 1 } };
- AuthRecord *rr;
- NetworkInterfaceInfo *intf = FirstInterfaceForID(m, InterfaceID);
- if (!intf) return;
-
- mDNS_Lock(m);
-
- // Pass 1:
- // Process ARP Requests and Probes (but not Announcements), and generate an ARP Reply if necessary.
- // We also process ARPs from our own kernel (and 'answer' them by injecting a local ARP table entry)
- // We ignore ARP Announcements here -- Announcements are not questions, they're assertions, so we don't need to answer them.
- // The times we might need to react to an ARP Announcement are:
- // (i) as an indication that the host in question has not gone to sleep yet (so we should delay beginning to proxy for it) or
- // (ii) if it's a conflicting Announcement from another host
- // -- and we check for these in Pass 2 below.
- if (mDNSSameOpaque16(arp->op, ARP_op_request) && !mDNSSameIPv4Address(arp->spa, arp->tpa))
- {
- for (rr = m->ResourceRecords; rr; rr=rr->next)
- if (rr->resrec.InterfaceID == InterfaceID && rr->resrec.RecordType != kDNSRecordTypeDeregistering &&
- rr->AddressProxy.type == mDNSAddrType_IPv4 && mDNSSameIPv4Address(rr->AddressProxy.ip.v4, arp->tpa))
- {
- static const char msg1[] = "ARP Req from owner -- re-probing";
- static const char msg2[] = "Ignoring ARP Request from ";
- static const char msg3[] = "Creating Local ARP Cache entry ";
- static const char msg4[] = "Answering ARP Request from ";
- const char *const msg = mDNSSameEthAddress(&arp->sha, &rr->WakeUp.IMAC) ? msg1 :
- (rr->AnnounceCount == InitialAnnounceCount) ? msg2 :
- mDNSSameEthAddress(&arp->sha, &intf->MAC) ? msg3 : msg4;
- LogSPS("%-7s %s %.6a %.4a for %.4a -- H-MAC %.6a I-MAC %.6a %s",
- intf->ifname, msg, &arp->sha, &arp->spa, &arp->tpa, &rr->WakeUp.HMAC, &rr->WakeUp.IMAC, ARDisplayString(m, rr));
- if (msg == msg1) RestartARPProbing(m, rr);
- else if (msg == msg3) mDNSPlatformSetLocalAddressCacheEntry(m, &rr->AddressProxy, &rr->WakeUp.IMAC, InterfaceID);
- else if (msg == msg4) SendARP(m, 2, rr, &arp->tpa, &arp->sha, &arp->spa, &arp->sha);
- }
- }
-
- // Pass 2:
- // For all types of ARP packet we check the Sender IP address to make sure it doesn't conflict with any AddressProxy record we're holding.
- // (Strictly speaking we're only checking Announcement/Request/Reply packets, since ARP Probes have zero Sender IP address,
- // so by definition (and by design) they can never conflict with any real (i.e. non-zero) IP address).
- // We ignore ARPs we sent ourselves (Sender MAC address is our MAC address) because our own proxy ARPs do not constitute a conflict that we need to handle.
- // If we see an apparently conflicting ARP, we check the sender hardware address:
- // If the sender hardware address is the original owner this is benign, so we just suppress our own proxy answering for a while longer.
- // If the sender hardware address is *not* the original owner, then this is a conflict, and we need to wake the sleeping machine to handle it.
- if (mDNSSameEthAddress(&arp->sha, &intf->MAC))
- debugf("ARP from self for %.4a", &arp->tpa);
- else
- {
- if (!mDNSSameIPv4Address(arp->spa, zerov4Addr))
- for (rr = m->ResourceRecords; rr; rr=rr->next)
- if (rr->resrec.InterfaceID == InterfaceID && rr->resrec.RecordType != kDNSRecordTypeDeregistering &&
- rr->AddressProxy.type == mDNSAddrType_IPv4 && mDNSSameIPv4Address(rr->AddressProxy.ip.v4, arp->spa))
- {
- RestartARPProbing(m, rr);
- if (mDNSSameEthAddress(&arp->sha, &rr->WakeUp.IMAC))
- LogSPS("%-7s ARP %s from owner %.6a %.4a for %-15.4a -- re-starting probing for %s", intf->ifname,
- mDNSSameIPv4Address(arp->spa, arp->tpa) ? "Announcement " : mDNSSameOpaque16(arp->op, ARP_op_request) ? "Request " : "Response ",
- &arp->sha, &arp->spa, &arp->tpa, ARDisplayString(m, rr));
- else
- {
- LogMsg("%-7s Conflicting ARP from %.6a %.4a for %.4a -- waking H-MAC %.6a I-MAC %.6a %s", intf->ifname,
- &arp->sha, &arp->spa, &arp->tpa, &rr->WakeUp.HMAC, &rr->WakeUp.IMAC, ARDisplayString(m, rr));
- ScheduleWakeup(m, rr->resrec.InterfaceID, &rr->WakeUp.HMAC);
- }
- }
- }
-
- mDNS_Unlock(m);
- }
+{
+ static const mDNSOpaque16 ARP_op_request = { { 0, 1 } };
+ AuthRecord *rr;
+ NetworkInterfaceInfo *intf = FirstInterfaceForID(m, InterfaceID);
+ if (!intf) return;
+
+ mDNS_Lock(m);
+
+ // Pass 1:
+ // Process ARP Requests and Probes (but not Announcements), and generate an ARP Reply if necessary.
+ // We also process ARPs from our own kernel (and 'answer' them by injecting a local ARP table entry)
+ // We ignore ARP Announcements here -- Announcements are not questions, they're assertions, so we don't need to answer them.
+ // The times we might need to react to an ARP Announcement are:
+ // (i) as an indication that the host in question has not gone to sleep yet (so we should delay beginning to proxy for it) or
+ // (ii) if it's a conflicting Announcement from another host
+ // -- and we check for these in Pass 2 below.
+ if (mDNSSameOpaque16(arp->op, ARP_op_request) && !mDNSSameIPv4Address(arp->spa, arp->tpa))
+ {
+ for (rr = m->ResourceRecords; rr; rr=rr->next)
+ if (rr->resrec.InterfaceID == InterfaceID && rr->resrec.RecordType != kDNSRecordTypeDeregistering &&
+ rr->AddressProxy.type == mDNSAddrType_IPv4 && mDNSSameIPv4Address(rr->AddressProxy.ip.v4, arp->tpa))
+ {
+ static const char msg1[] = "ARP Req from owner -- re-probing";
+ static const char msg2[] = "Ignoring ARP Request from ";
+ static const char msg3[] = "Creating Local ARP Cache entry ";
+ static const char msg4[] = "Answering ARP Request from ";
+ const char *const msg = mDNSSameEthAddress(&arp->sha, &rr->WakeUp.IMAC) ? msg1 :
+ (rr->AnnounceCount == InitialAnnounceCount) ? msg2 :
+ mDNSSameEthAddress(&arp->sha, &intf->MAC) ? msg3 : msg4;
+ LogSPS("%-7s %s %.6a %.4a for %.4a -- H-MAC %.6a I-MAC %.6a %s",
+ intf->ifname, msg, &arp->sha, &arp->spa, &arp->tpa, &rr->WakeUp.HMAC, &rr->WakeUp.IMAC, ARDisplayString(m, rr));
+ if (msg == msg1)
+ {
+ if ( rr->ProbeRestartCount < MAX_PROBE_RESTARTS)
+ RestartARPProbing(m, rr);
+ else
+ LogSPS("Reached maximum number of restarts for probing - %s", ARDisplayString(m,rr));
+ }
+ else if (msg == msg3)
+ {
+ mDNSPlatformSetLocalAddressCacheEntry(m, &rr->AddressProxy, &rr->WakeUp.IMAC, InterfaceID);
+ }
+ else if (msg == msg4)
+ {
+ SendARP(m, 2, rr, &arp->tpa, &arp->sha, &arp->spa, &arp->sha);
+ }
+ }
+ }
+
+ // Pass 2:
+ // For all types of ARP packet we check the Sender IP address to make sure it doesn't conflict with any AddressProxy record we're holding.
+ // (Strictly speaking we're only checking Announcement/Request/Reply packets, since ARP Probes have zero Sender IP address,
+ // so by definition (and by design) they can never conflict with any real (i.e. non-zero) IP address).
+ // We ignore ARPs we sent ourselves (Sender MAC address is our MAC address) because our own proxy ARPs do not constitute a conflict that we need to handle.
+ // If we see an apparently conflicting ARP, we check the sender hardware address:
+ // If the sender hardware address is the original owner this is benign, so we just suppress our own proxy answering for a while longer.
+ // If the sender hardware address is *not* the original owner, then this is a conflict, and we need to wake the sleeping machine to handle it.
+ if (mDNSSameEthAddress(&arp->sha, &intf->MAC))
+ debugf("ARP from self for %.4a", &arp->tpa);
+ else
+ {
+ if (!mDNSSameIPv4Address(arp->spa, zerov4Addr))
+ for (rr = m->ResourceRecords; rr; rr=rr->next)
+ if (rr->resrec.InterfaceID == InterfaceID && rr->resrec.RecordType != kDNSRecordTypeDeregistering &&
+ rr->AddressProxy.type == mDNSAddrType_IPv4 && mDNSSameIPv4Address(rr->AddressProxy.ip.v4, arp->spa) && (rr->ProbeRestartCount < MAX_PROBE_RESTARTS))
+ {
+ if (mDNSSameEthAddress(&zeroEthAddr, &rr->WakeUp.HMAC))
+ {
+ LogSPS("%-7s ARP from %.6a %.4a for %.4a -- Invalid H-MAC %.6a I-MAC %.6a %s", intf->ifname,
+ &arp->sha, &arp->spa, &arp->tpa, &rr->WakeUp.HMAC, &rr->WakeUp.IMAC, ARDisplayString(m, rr));
+ }
+ else
+ {
+ RestartARPProbing(m, rr);
+ if (mDNSSameEthAddress(&arp->sha, &rr->WakeUp.IMAC))
+ {
+ LogSPS("%-7s ARP %s from owner %.6a %.4a for %-15.4a -- re-starting probing for %s", intf->ifname,
+ mDNSSameIPv4Address(arp->spa, arp->tpa) ? "Announcement " : mDNSSameOpaque16(arp->op, ARP_op_request) ? "Request " : "Response ",
+ &arp->sha, &arp->spa, &arp->tpa, ARDisplayString(m, rr));
+ }
+ else
+ {
+ LogMsg("%-7s Conflicting ARP from %.6a %.4a for %.4a -- waking H-MAC %.6a I-MAC %.6a %s", intf->ifname,
+ &arp->sha, &arp->spa, &arp->tpa, &rr->WakeUp.HMAC, &rr->WakeUp.IMAC, ARDisplayString(m, rr));
+ ScheduleWakeup(m, rr->resrec.InterfaceID, &rr->WakeUp.HMAC);
+ }
+ }
+ }
+ }
+
+ mDNS_Unlock(m);
+}
/*
-// Option 1 is Source Link Layer Address Option
-// Option 2 is Target Link Layer Address Option
-mDNSlocal const mDNSEthAddr *GetLinkLayerAddressOption(const IPv6NDP *const ndp, const mDNSu8 *const end, mDNSu8 op)
- {
- const mDNSu8 *options = (mDNSu8 *)(ndp+1);
- while (options < end)
- {
- debugf("NDP Option %02X len %2d %d", options[0], options[1], end - options);
- if (options[0] == op && options[1] == 1) return (const mDNSEthAddr*)(options+2);
- options += options[1] * 8;
- }
- return mDNSNULL;
- }
-*/
+ // Option 1 is Source Link Layer Address Option
+ // Option 2 is Target Link Layer Address Option
+ mDNSlocal const mDNSEthAddr *GetLinkLayerAddressOption(const IPv6NDP *const ndp, const mDNSu8 *const end, mDNSu8 op)
+ {
+ const mDNSu8 *options = (mDNSu8 *)(ndp+1);
+ while (options < end)
+ {
+ debugf("NDP Option %02X len %2d %d", options[0], options[1], end - options);
+ if (options[0] == op && options[1] == 1) return (const mDNSEthAddr*)(options+2);
+ options += options[1] * 8;
+ }
+ return mDNSNULL;
+ }
+ */
mDNSlocal void mDNSCoreReceiveRawND(mDNS *const m, const mDNSEthAddr *const sha, const mDNSv6Addr *spa,
- const IPv6NDP *const ndp, const mDNSu8 *const end, const mDNSInterfaceID InterfaceID)
- {
- AuthRecord *rr;
- NetworkInterfaceInfo *intf = FirstInterfaceForID(m, InterfaceID);
- if (!intf) return;
-
- mDNS_Lock(m);
-
- // Pass 1: Process Neighbor Solicitations, and generate a Neighbor Advertisement if necessary.
- if (ndp->type == NDP_Sol)
- {
- //const mDNSEthAddr *const sha = GetLinkLayerAddressOption(ndp, end, NDP_SrcLL);
- (void)end;
- for (rr = m->ResourceRecords; rr; rr=rr->next)
- if (rr->resrec.InterfaceID == InterfaceID && rr->resrec.RecordType != kDNSRecordTypeDeregistering &&
- rr->AddressProxy.type == mDNSAddrType_IPv6 && mDNSSameIPv6Address(rr->AddressProxy.ip.v6, ndp->target))
- {
- static const char msg1[] = "NDP Req from owner -- re-probing";
- static const char msg2[] = "Ignoring NDP Request from ";
- static const char msg3[] = "Creating Local NDP Cache entry ";
- static const char msg4[] = "Answering NDP Request from ";
- static const char msg5[] = "Answering NDP Probe from ";
- const char *const msg = sha && mDNSSameEthAddress(sha, &rr->WakeUp.IMAC) ? msg1 :
- (rr->AnnounceCount == InitialAnnounceCount) ? msg2 :
- sha && mDNSSameEthAddress(sha, &intf->MAC) ? msg3 :
- spa && mDNSIPv6AddressIsZero(*spa) ? msg4 : msg5;
- LogSPS("%-7s %s %.6a %.16a for %.16a -- H-MAC %.6a I-MAC %.6a %s",
- intf->ifname, msg, sha, spa, &ndp->target, &rr->WakeUp.HMAC, &rr->WakeUp.IMAC, ARDisplayString(m, rr));
- if (msg == msg1) RestartARPProbing(m, rr);
- else if (msg == msg3)
- {
- if (!(m->KnownBugs & mDNS_KnownBug_LimitedIPv6))
- mDNSPlatformSetLocalAddressCacheEntry(m, &rr->AddressProxy, &rr->WakeUp.IMAC, InterfaceID);
- }
- else if (msg == msg4) SendNDP(m, NDP_Adv, NDP_Solicited, rr, &ndp->target, mDNSNULL, spa, sha );
- else if (msg == msg5) SendNDP(m, NDP_Adv, 0, rr, &ndp->target, mDNSNULL, &AllHosts_v6, &AllHosts_v6_Eth);
- }
- }
-
- // Pass 2: For all types of NDP packet we check the Sender IP address to make sure it doesn't conflict with any AddressProxy record we're holding.
- if (mDNSSameEthAddress(sha, &intf->MAC))
- debugf("NDP from self for %.16a", &ndp->target);
- else
- {
- // For Neighbor Advertisements we check the Target address field, not the actual IPv6 source address.
- // When a machine has both link-local and routable IPv6 addresses, it may send NDP packets making assertions
- // about its routable IPv6 address, using its link-local address as the source address for all NDP packets.
- // Hence it is the NDP target address we care about, not the actual packet source address.
- if (ndp->type == NDP_Adv) spa = &ndp->target;
- if (!mDNSSameIPv6Address(*spa, zerov6Addr))
- for (rr = m->ResourceRecords; rr; rr=rr->next)
- if (rr->resrec.InterfaceID == InterfaceID && rr->resrec.RecordType != kDNSRecordTypeDeregistering &&
- rr->AddressProxy.type == mDNSAddrType_IPv6 && mDNSSameIPv6Address(rr->AddressProxy.ip.v6, *spa))
- {
- RestartARPProbing(m, rr);
- if (mDNSSameEthAddress(sha, &rr->WakeUp.IMAC))
- LogSPS("%-7s NDP %s from owner %.6a %.16a for %.16a -- re-starting probing for %s", intf->ifname,
- ndp->type == NDP_Sol ? "Solicitation " : "Advertisement", sha, spa, &ndp->target, ARDisplayString(m, rr));
- else
- {
- LogMsg("%-7s Conflicting NDP from %.6a %.16a for %.16a -- waking H-MAC %.6a I-MAC %.6a %s", intf->ifname,
- sha, spa, &ndp->target, &rr->WakeUp.HMAC, &rr->WakeUp.IMAC, ARDisplayString(m, rr));
- ScheduleWakeup(m, rr->resrec.InterfaceID, &rr->WakeUp.HMAC);
- }
- }
- }
-
- mDNS_Unlock(m);
- }
+ const IPv6NDP *const ndp, const mDNSu8 *const end, const mDNSInterfaceID InterfaceID)
+{
+ AuthRecord *rr;
+ NetworkInterfaceInfo *intf = FirstInterfaceForID(m, InterfaceID);
+ if (!intf) return;
+
+ mDNS_Lock(m);
+
+ // Pass 1: Process Neighbor Solicitations, and generate a Neighbor Advertisement if necessary.
+ if (ndp->type == NDP_Sol)
+ {
+ //const mDNSEthAddr *const sha = GetLinkLayerAddressOption(ndp, end, NDP_SrcLL);
+ (void)end;
+ for (rr = m->ResourceRecords; rr; rr=rr->next)
+ if (rr->resrec.InterfaceID == InterfaceID && rr->resrec.RecordType != kDNSRecordTypeDeregistering &&
+ rr->AddressProxy.type == mDNSAddrType_IPv6 && mDNSSameIPv6Address(rr->AddressProxy.ip.v6, ndp->target))
+ {
+ static const char msg1[] = "NDP Req from owner -- re-probing";
+ static const char msg2[] = "Ignoring NDP Request from ";
+ static const char msg3[] = "Creating Local NDP Cache entry ";
+ static const char msg4[] = "Answering NDP Request from ";
+ static const char msg5[] = "Answering NDP Probe from ";
+ const char *const msg = sha && mDNSSameEthAddress(sha, &rr->WakeUp.IMAC) ? msg1 :
+ (rr->AnnounceCount == InitialAnnounceCount) ? msg2 :
+ sha && mDNSSameEthAddress(sha, &intf->MAC) ? msg3 :
+ spa && mDNSIPv6AddressIsZero(*spa) ? msg4 : msg5;
+ LogSPS("%-7s %s %.6a %.16a for %.16a -- H-MAC %.6a I-MAC %.6a %s",
+ intf->ifname, msg, sha, spa, &ndp->target, &rr->WakeUp.HMAC, &rr->WakeUp.IMAC, ARDisplayString(m, rr));
+ if (msg == msg1)
+ {
+ if (rr->ProbeRestartCount < MAX_PROBE_RESTARTS)
+ RestartARPProbing(m, rr);
+ else
+ LogSPS("Reached maximum number of restarts for probing - %s", ARDisplayString(m,rr));
+ }
+ else if (msg == msg3)
+ mDNSPlatformSetLocalAddressCacheEntry(m, &rr->AddressProxy, &rr->WakeUp.IMAC, InterfaceID);
+ else if (msg == msg4)
+ SendNDP(m, NDP_Adv, NDP_Solicited, rr, &ndp->target, mDNSNULL, spa, sha);
+ else if (msg == msg5)
+ SendNDP(m, NDP_Adv, 0, rr, &ndp->target, mDNSNULL, &AllHosts_v6, &AllHosts_v6_Eth);
+ }
+ }
+
+ // Pass 2: For all types of NDP packet we check the Sender IP address to make sure it doesn't conflict with any AddressProxy record we're holding.
+ if (mDNSSameEthAddress(sha, &intf->MAC))
+ debugf("NDP from self for %.16a", &ndp->target);
+ else
+ {
+ // For Neighbor Advertisements we check the Target address field, not the actual IPv6 source address.
+ // When a machine has both link-local and routable IPv6 addresses, it may send NDP packets making assertions
+ // about its routable IPv6 address, using its link-local address as the source address for all NDP packets.
+ // Hence it is the NDP target address we care about, not the actual packet source address.
+ if (ndp->type == NDP_Adv) spa = &ndp->target;
+ if (!mDNSSameIPv6Address(*spa, zerov6Addr))
+ for (rr = m->ResourceRecords; rr; rr=rr->next)
+ if (rr->resrec.InterfaceID == InterfaceID && rr->resrec.RecordType != kDNSRecordTypeDeregistering &&
+ rr->AddressProxy.type == mDNSAddrType_IPv6 && mDNSSameIPv6Address(rr->AddressProxy.ip.v6, *spa) && (rr->ProbeRestartCount < MAX_PROBE_RESTARTS))
+ {
+ if (mDNSSameEthAddress(&zeroEthAddr, &rr->WakeUp.HMAC))
+ {
+ LogSPS("%-7s NDP from %.6a %.16a for %.16a -- Invalid H-MAC %.6a I-MAC %.6a %s", intf->ifname,
+ sha, spa, &ndp->target, &rr->WakeUp.HMAC, &rr->WakeUp.IMAC, ARDisplayString(m, rr));
+ }
+ else
+ {
+ RestartARPProbing(m, rr);
+ if (mDNSSameEthAddress(sha, &rr->WakeUp.IMAC))
+ {
+ LogSPS("%-7s NDP %s from owner %.6a %.16a for %.16a -- re-starting probing for %s", intf->ifname,
+ ndp->type == NDP_Sol ? "Solicitation " : "Advertisement", sha, spa, &ndp->target, ARDisplayString(m, rr));
+ }
+ else
+ {
+ LogMsg("%-7s Conflicting NDP from %.6a %.16a for %.16a -- waking H-MAC %.6a I-MAC %.6a %s", intf->ifname,
+ sha, spa, &ndp->target, &rr->WakeUp.HMAC, &rr->WakeUp.IMAC, ARDisplayString(m, rr));
+ ScheduleWakeup(m, rr->resrec.InterfaceID, &rr->WakeUp.HMAC);
+ }
+ }
+ }
+ }
+
+ mDNS_Unlock(m);
+}
mDNSlocal void mDNSCoreReceiveRawTransportPacket(mDNS *const m, const mDNSEthAddr *const sha, const mDNSAddr *const src, const mDNSAddr *const dst, const mDNSu8 protocol,
- const mDNSu8 *const p, const TransportLayerPacket *const t, const mDNSu8 *const end, const mDNSInterfaceID InterfaceID, const mDNSu16 len)
- {
- const mDNSIPPort port = (protocol == 0x06) ? t->tcp.dst : (protocol == 0x11) ? t->udp.dst : zeroIPPort;
- mDNSBool wake = mDNSfalse;
-
- switch (protocol)
- {
- #define XX wake ? "Received" : "Ignoring", end-p
- case 0x01: LogSPS("Ignoring %d-byte ICMP from %#a to %#a", end-p, src, dst);
- break;
-
- case 0x06: {
- #define SSH_AsNumber 22
- static const mDNSIPPort SSH = { { SSH_AsNumber >> 8, SSH_AsNumber & 0xFF } };
-
- // Plan to wake if
- // (a) RST is not set, AND
- // (b) packet is SYN, SYN+FIN, or plain data packet (no SYN or FIN). We won't wake for FIN alone.
- wake = (!(t->tcp.flags & 4) && (t->tcp.flags & 3) != 1);
-
- // For now, to reduce spurious wakeups, we wake only for TCP SYN,
- // except for ssh connections, where we'll wake for plain data packets too
- if (!mDNSSameIPPort(port, SSH) && !(t->tcp.flags & 2)) wake = mDNSfalse;
-
- LogSPS("%s %d-byte TCP from %#a:%d to %#a:%d%s%s%s", XX,
- src, mDNSVal16(t->tcp.src), dst, mDNSVal16(port),
- (t->tcp.flags & 2) ? " SYN" : "",
- (t->tcp.flags & 1) ? " FIN" : "",
- (t->tcp.flags & 4) ? " RST" : "");
- }
- break;
-
- case 0x11: {
- #define ARD_AsNumber 3283
- static const mDNSIPPort ARD = { { ARD_AsNumber >> 8, ARD_AsNumber & 0xFF } };
- const mDNSu16 udplen = (mDNSu16)((mDNSu16)t->bytes[4] << 8 | t->bytes[5]); // Length *including* 8-byte UDP header
- if (udplen >= sizeof(UDPHeader))
- {
- const mDNSu16 datalen = udplen - sizeof(UDPHeader);
- wake = mDNStrue;
-
- // For Back to My Mac UDP port 4500 (IPSEC) packets, we do some special handling
- if (mDNSSameIPPort(port, IPSECPort))
- {
- // Specifically ignore NAT keepalive packets
- if (datalen == 1 && end >= &t->bytes[9] && t->bytes[8] == 0xFF) wake = mDNSfalse;
- else
- {
- // Skip over the Non-ESP Marker if present
- const mDNSBool NonESP = (end >= &t->bytes[12] && t->bytes[8] == 0 && t->bytes[9] == 0 && t->bytes[10] == 0 && t->bytes[11] == 0);
- const IKEHeader *const ike = (IKEHeader *)(t + (NonESP ? 12 : 8));
- const mDNSu16 ikelen = datalen - (NonESP ? 4 : 0);
- if (ikelen >= sizeof(IKEHeader) && end >= ((mDNSu8 *)ike) + sizeof(IKEHeader))
- if ((ike->Version & 0x10) == 0x10)
- {
- // ExchangeType == 5 means 'Informational' <http://www.ietf.org/rfc/rfc2408.txt>
- // ExchangeType == 34 means 'IKE_SA_INIT' <http://www.iana.org/assignments/ikev2-parameters>
- if (ike->ExchangeType == 5 || ike->ExchangeType == 34) wake = mDNSfalse;
- LogSPS("%s %d-byte IKE ExchangeType %d", XX, ike->ExchangeType);
- }
- }
- }
-
- // For now, because we haven't yet worked out a clean elegant way to do this, we just special-case the
- // Apple Remote Desktop port number -- we ignore all packets to UDP 3283 (the "Net Assistant" port),
- // except for Apple Remote Desktop's explicit manual wakeup packet, which looks like this:
- // UDP header (8 bytes)
- // Payload: 13 88 00 6a 41 4e 41 20 (8 bytes) ffffffffffff (6 bytes) 16xMAC (96 bytes) = 110 bytes total
- if (mDNSSameIPPort(port, ARD)) wake = (datalen >= 110 && end >= &t->bytes[10] && t->bytes[8] == 0x13 && t->bytes[9] == 0x88);
-
- LogSPS("%s %d-byte UDP from %#a:%d to %#a:%d", XX, src, mDNSVal16(t->udp.src), dst, mDNSVal16(port));
- }
- }
- break;
-
- case 0x3A: if (&t->bytes[len] <= end)
- {
- mDNSu16 checksum = IPv6CheckSum(&src->ip.v6, &dst->ip.v6, protocol, t->bytes, len);
- if (!checksum) mDNSCoreReceiveRawND(m, sha, &src->ip.v6, &t->ndp, &t->bytes[len], InterfaceID);
- else LogInfo("IPv6CheckSum bad %04X %02X%02X from %#a to %#a", checksum, t->bytes[2], t->bytes[3], src, dst);
- }
- break;
-
- default: LogSPS("Ignoring %d-byte IP packet unknown protocol %d from %#a to %#a", end-p, protocol, src, dst);
- break;
- }
-
- if (wake)
- {
- AuthRecord *rr, *r2;
-
- mDNS_Lock(m);
- for (rr = m->ResourceRecords; rr; rr=rr->next)
- if (rr->resrec.InterfaceID == InterfaceID &&
- rr->resrec.RecordType != kDNSRecordTypeDeregistering &&
- rr->AddressProxy.type && mDNSSameAddress(&rr->AddressProxy, dst))
- {
- const mDNSu8 *const tp = (protocol == 6) ? (const mDNSu8 *)"\x4_tcp" : (const mDNSu8 *)"\x4_udp";
- for (r2 = m->ResourceRecords; r2; r2=r2->next)
- if (r2->resrec.InterfaceID == InterfaceID && mDNSSameEthAddress(&r2->WakeUp.HMAC, &rr->WakeUp.HMAC) &&
- r2->resrec.RecordType != kDNSRecordTypeDeregistering &&
- r2->resrec.rrtype == kDNSType_SRV && mDNSSameIPPort(r2->resrec.rdata->u.srv.port, port) &&
- SameDomainLabel(ThirdLabel(r2->resrec.name)->c, tp))
- break;
- if (!r2 && mDNSSameIPPort(port, IPSECPort)) r2 = rr; // So that we wake for BTMM IPSEC packets, even without a matching SRV record
- if (r2)
- {
- LogMsg("Waking host at %s %#a H-MAC %.6a I-MAC %.6a for %s",
- InterfaceNameForID(m, rr->resrec.InterfaceID), dst, &rr->WakeUp.HMAC, &rr->WakeUp.IMAC, ARDisplayString(m, r2));
- ScheduleWakeup(m, rr->resrec.InterfaceID, &rr->WakeUp.HMAC);
- }
- else
- LogSPS("Sleeping host at %s %#a %.6a has no service on %#s %d",
- InterfaceNameForID(m, rr->resrec.InterfaceID), dst, &rr->WakeUp.HMAC, tp, mDNSVal16(port));
- }
- mDNS_Unlock(m);
- }
- }
+ const mDNSu8 *const p, const TransportLayerPacket *const t, const mDNSu8 *const end, const mDNSInterfaceID InterfaceID, const mDNSu16 len)
+{
+ const mDNSIPPort port = (protocol == 0x06) ? t->tcp.dst : (protocol == 0x11) ? t->udp.dst : zeroIPPort;
+ mDNSBool wake = mDNSfalse;
+ mDNSBool kaWake = mDNSfalse;
+
+ switch (protocol)
+ {
+ #define XX wake ? "Received" : "Ignoring", end-p
+ case 0x01: LogSPS("Ignoring %d-byte ICMP from %#a to %#a", end-p, src, dst);
+ break;
+
+ case 0x06: {
+ AuthRecord *kr;
+ mDNSu32 seq, ack;
+ #define TH_FIN 0x01
+ #define TH_SYN 0x02
+ #define TH_RST 0x04
+ #define TH_ACK 0x10
+
+ kr = mDNS_MatchKeepaliveInfo(m, dst, src, port, t->tcp.src, &seq, &ack);
+ if (kr)
+ {
+ LogSPS("mDNSCoreReceiveRawTransportPacket: Found a Keepalive record from %#a:%d to %#a:%d", src, mDNSVal16(t->tcp.src), dst, mDNSVal16(port));
+ // Plan to wake if
+ // (a) RST or FIN is set (the keepalive that we sent could have caused a reset)
+ // (b) packet that contains new data and acks a sequence number higher than the one
+ // we have been sending in the keepalive
+
+ wake = ((t->tcp.flags & TH_RST) || (t->tcp.flags & TH_FIN)) ;
+ if (!wake)
+ {
+ mDNSu8 *ptr;
+ mDNSu32 pseq, pack;
+ mDNSBool data = mDNSfalse;
+ mDNSu8 tcphlen;
+
+ // Convert to host order
+ ptr = (mDNSu8 *)&seq;
+ seq = ptr[0] << 24 | ptr[1] << 16 | ptr[2] << 8 | ptr[3];
+
+ ptr = (mDNSu8 *)&ack;
+ ack = ptr[0] << 24 | ptr[1] << 16 | ptr[2] << 8 | ptr[3];
+
+ pseq = t->tcp.seq;
+ ptr = (mDNSu8 *)&pseq;
+ pseq = ptr[0] << 24 | ptr[1] << 16 | ptr[2] << 8 | ptr[3];
+
+ pack = t->tcp.ack;
+ ptr = (mDNSu8 *)&pack;
+ pack = ptr[0] << 24 | ptr[1] << 16 | ptr[2] << 8 | ptr[3];
+
+ // If the other side is acking one more than our sequence number (keepalive is one
+ // less than the last valid sequence sent) and it's sequence is more than what we
+ // acked before
+ //if (end - p - 34 - ((t->tcp.offset >> 4) * 4) > 0) data = mDNStrue;
+ tcphlen = ((t->tcp.offset >> 4) * 4);
+ if (end - ((mDNSu8 *)t + tcphlen) > 0) data = mDNStrue;
+ wake = ((int)(pack - seq) > 0) && ((int)(pseq - ack) >= 0) && data;
+
+ // If we got a regular keepalive on a connection that was registed with the KeepAlive API, respond with an ACK
+ if ((t->tcp.flags & TH_ACK) && (data == mDNSfalse) &&
+ ((int)(ack - pseq) == 1))
+ {
+ // Send an ACK;
+ mDNS_SendKeepaliveACK(m, kr);
+ }
+ LogSPS("mDNSCoreReceiveRawTransportPacket: End %p, hlen %d, Datalen %d, pack %u, seq %u, pseq %u, ack %u, wake %d",
+ end, tcphlen, end - ((mDNSu8 *)t + tcphlen), pack, seq, pseq, ack, wake);
+ }
+ else { LogSPS("mDNSCoreReceiveRawTransportPacket: waking because of RST or FIN th_flags %d", t->tcp.flags); }
+ kaWake = wake;
+ }
+ else
+ {
+ // Plan to wake if
+ // (a) RST is not set, AND
+ // (b) packet is SYN, SYN+FIN, or plain data packet (no SYN or FIN). We won't wake for FIN alone.
+ wake = (!(t->tcp.flags & TH_RST) && (t->tcp.flags & (TH_FIN|TH_SYN)) != TH_FIN);
+
+ // For now, to reduce spurious wakeups, we wake only for TCP SYN,
+ // except for ssh connections, where we'll wake for plain data packets too
+ if (!mDNSSameIPPort(port, SSHPort) && !(t->tcp.flags & 2)) wake = mDNSfalse;
+
+ LogSPS("%s %d-byte TCP from %#a:%d to %#a:%d%s%s%s", XX,
+ src, mDNSVal16(t->tcp.src), dst, mDNSVal16(port),
+ (t->tcp.flags & 2) ? " SYN" : "",
+ (t->tcp.flags & 1) ? " FIN" : "",
+ (t->tcp.flags & 4) ? " RST" : "");
+ }
+ break;
+ }
+
+ case 0x11: {
+ #define ARD_AsNumber 3283
+ static const mDNSIPPort ARD = { { ARD_AsNumber >> 8, ARD_AsNumber & 0xFF } };
+ const mDNSu16 udplen = (mDNSu16)((mDNSu16)t->bytes[4] << 8 | t->bytes[5]); // Length *including* 8-byte UDP header
+ if (udplen >= sizeof(UDPHeader))
+ {
+ const mDNSu16 datalen = udplen - sizeof(UDPHeader);
+ wake = mDNStrue;
+
+ // For Back to My Mac UDP port 4500 (IPSEC) packets, we do some special handling
+ if (mDNSSameIPPort(port, IPSECPort))
+ {
+ // Specifically ignore NAT keepalive packets
+ if (datalen == 1 && end >= &t->bytes[9] && t->bytes[8] == 0xFF) wake = mDNSfalse;
+ else
+ {
+ // Skip over the Non-ESP Marker if present
+ const mDNSBool NonESP = (end >= &t->bytes[12] && t->bytes[8] == 0 && t->bytes[9] == 0 && t->bytes[10] == 0 && t->bytes[11] == 0);
+ const IKEHeader *const ike = (IKEHeader *)(t + (NonESP ? 12 : 8));
+ const mDNSu16 ikelen = datalen - (NonESP ? 4 : 0);
+ if (ikelen >= sizeof(IKEHeader) && end >= ((mDNSu8 *)ike) + sizeof(IKEHeader))
+ if ((ike->Version & 0x10) == 0x10)
+ {
+ // ExchangeType == 5 means 'Informational' <http://www.ietf.org/rfc/rfc2408.txt>
+ // ExchangeType == 34 means 'IKE_SA_INIT' <http://www.iana.org/assignments/ikev2-parameters>
+ if (ike->ExchangeType == 5 || ike->ExchangeType == 34) wake = mDNSfalse;
+ LogSPS("%s %d-byte IKE ExchangeType %d", XX, ike->ExchangeType);
+ }
+ }
+ }
+
+ // For now, because we haven't yet worked out a clean elegant way to do this, we just special-case the
+ // Apple Remote Desktop port number -- we ignore all packets to UDP 3283 (the "Net Assistant" port),
+ // except for Apple Remote Desktop's explicit manual wakeup packet, which looks like this:
+ // UDP header (8 bytes)
+ // Payload: 13 88 00 6a 41 4e 41 20 (8 bytes) ffffffffffff (6 bytes) 16xMAC (96 bytes) = 110 bytes total
+ if (mDNSSameIPPort(port, ARD)) wake = (datalen >= 110 && end >= &t->bytes[10] && t->bytes[8] == 0x13 && t->bytes[9] == 0x88);
+
+ LogSPS("%s %d-byte UDP from %#a:%d to %#a:%d", XX, src, mDNSVal16(t->udp.src), dst, mDNSVal16(port));
+ }
+ }
+ break;
+
+ case 0x3A: if (&t->bytes[len] <= end)
+ {
+ mDNSu16 checksum = IPv6CheckSum(&src->ip.v6, &dst->ip.v6, protocol, t->bytes, len);
+ if (!checksum) mDNSCoreReceiveRawND(m, sha, &src->ip.v6, &t->ndp, &t->bytes[len], InterfaceID);
+ else LogInfo("IPv6CheckSum bad %04X %02X%02X from %#a to %#a", checksum, t->bytes[2], t->bytes[3], src, dst);
+ }
+ break;
+
+ default: LogSPS("Ignoring %d-byte IP packet unknown protocol %d from %#a to %#a", end-p, protocol, src, dst);
+ break;
+ }
+
+ if (wake)
+ {
+ AuthRecord *rr, *r2;
+
+ mDNS_Lock(m);
+ for (rr = m->ResourceRecords; rr; rr=rr->next)
+ if (rr->resrec.InterfaceID == InterfaceID &&
+ rr->resrec.RecordType != kDNSRecordTypeDeregistering &&
+ rr->AddressProxy.type && mDNSSameAddress(&rr->AddressProxy, dst))
+ {
+ const mDNSu8 *const tp = (protocol == 6) ? (const mDNSu8 *)"\x4_tcp" : (const mDNSu8 *)"\x4_udp";
+ for (r2 = m->ResourceRecords; r2; r2=r2->next)
+ if (r2->resrec.InterfaceID == InterfaceID && mDNSSameEthAddress(&r2->WakeUp.HMAC, &rr->WakeUp.HMAC) &&
+ r2->resrec.RecordType != kDNSRecordTypeDeregistering &&
+ r2->resrec.rrtype == kDNSType_SRV && mDNSSameIPPort(r2->resrec.rdata->u.srv.port, port) &&
+ SameDomainLabel(ThirdLabel(r2->resrec.name)->c, tp))
+ break;
+ if (!r2 && mDNSSameIPPort(port, IPSECPort)) r2 = rr; // So that we wake for BTMM IPSEC packets, even without a matching SRV record
+ if (!r2 && kaWake) r2 = rr; // So that we wake for keepalive packets, even without a matching SRV record
+ if (r2)
+ {
+ LogMsg("Waking host at %s %#a H-MAC %.6a I-MAC %.6a for %s",
+ InterfaceNameForID(m, rr->resrec.InterfaceID), dst, &rr->WakeUp.HMAC, &rr->WakeUp.IMAC, ARDisplayString(m, r2));
+ ScheduleWakeup(m, rr->resrec.InterfaceID, &rr->WakeUp.HMAC);
+ }
+ else
+ LogSPS("Sleeping host at %s %#a %.6a has no service on %#s %d",
+ InterfaceNameForID(m, rr->resrec.InterfaceID), dst, &rr->WakeUp.HMAC, tp, mDNSVal16(port));
+ }
+ mDNS_Unlock(m);
+ }
+}
mDNSexport void mDNSCoreReceiveRawPacket(mDNS *const m, const mDNSu8 *const p, const mDNSu8 *const end, const mDNSInterfaceID InterfaceID)
- {
- static const mDNSOpaque16 Ethertype_ARP = { { 0x08, 0x06 } }; // Ethertype 0x0806 = ARP
- static const mDNSOpaque16 Ethertype_IPv4 = { { 0x08, 0x00 } }; // Ethertype 0x0800 = IPv4
- static const mDNSOpaque16 Ethertype_IPv6 = { { 0x86, 0xDD } }; // Ethertype 0x86DD = IPv6
- static const mDNSOpaque16 ARP_hrd_eth = { { 0x00, 0x01 } }; // Hardware address space (Ethernet = 1)
- static const mDNSOpaque16 ARP_pro_ip = { { 0x08, 0x00 } }; // Protocol address space (IP = 0x0800)
-
- // Note: BPF guarantees that the NETWORK LAYER header will be word aligned, not the link-layer header.
- // In other words, we can safely assume that pkt below (ARP, IPv4 or IPv6) is properly word aligned,
- // but if pkt is 4-byte aligned, that necessarily means that eth CANNOT also be 4-byte aligned
- // since it points to a an address 14 bytes before pkt.
- const EthernetHeader *const eth = (const EthernetHeader *)p;
- const NetworkLayerPacket *const pkt = (const NetworkLayerPacket *)(eth+1);
- mDNSAddr src, dst;
- #define RequiredCapLen(P) ((P)==0x01 ? 4 : (P)==0x06 ? 20 : (P)==0x11 ? 8 : (P)==0x3A ? 24 : 0)
-
- // Is ARP? Length must be at least 14 + 28 = 42 bytes
- if (end >= p+42 && mDNSSameOpaque16(eth->ethertype, Ethertype_ARP) && mDNSSameOpaque16(pkt->arp.hrd, ARP_hrd_eth) && mDNSSameOpaque16(pkt->arp.pro, ARP_pro_ip))
- mDNSCoreReceiveRawARP(m, &pkt->arp, InterfaceID);
- // Is IPv4 with zero fragmentation offset? Length must be at least 14 + 20 = 34 bytes
- else if (end >= p+34 && mDNSSameOpaque16(eth->ethertype, Ethertype_IPv4) && (pkt->v4.flagsfrags.b[0] & 0x1F) == 0 && pkt->v4.flagsfrags.b[1] == 0)
- {
- const mDNSu8 *const trans = p + 14 + (pkt->v4.vlen & 0xF) * 4;
- debugf("Got IPv4 %02X from %.4a to %.4a", pkt->v4.protocol, &pkt->v4.src, &pkt->v4.dst);
- src.type = mDNSAddrType_IPv4; src.ip.v4 = pkt->v4.src;
- dst.type = mDNSAddrType_IPv4; dst.ip.v4 = pkt->v4.dst;
- if (end >= trans + RequiredCapLen(pkt->v4.protocol))
- mDNSCoreReceiveRawTransportPacket(m, ð->src, &src, &dst, pkt->v4.protocol, p, (TransportLayerPacket*)trans, end, InterfaceID, 0);
- }
- // Is IPv6? Length must be at least 14 + 28 = 42 bytes
- else if (end >= p+54 && mDNSSameOpaque16(eth->ethertype, Ethertype_IPv6))
- {
- const mDNSu8 *const trans = p + 54;
- debugf("Got IPv6 %02X from %.16a to %.16a", pkt->v6.pro, &pkt->v6.src, &pkt->v6.dst);
- src.type = mDNSAddrType_IPv6; src.ip.v6 = pkt->v6.src;
- dst.type = mDNSAddrType_IPv6; dst.ip.v6 = pkt->v6.dst;
- if (end >= trans + RequiredCapLen(pkt->v6.pro))
- mDNSCoreReceiveRawTransportPacket(m, ð->src, &src, &dst, pkt->v6.pro, p, (TransportLayerPacket*)trans, end, InterfaceID,
- (mDNSu16)pkt->bytes[4] << 8 | pkt->bytes[5]);
- }
- }
+{
+ static const mDNSOpaque16 Ethertype_ARP = { { 0x08, 0x06 } }; // Ethertype 0x0806 = ARP
+ static const mDNSOpaque16 Ethertype_IPv4 = { { 0x08, 0x00 } }; // Ethertype 0x0800 = IPv4
+ static const mDNSOpaque16 Ethertype_IPv6 = { { 0x86, 0xDD } }; // Ethertype 0x86DD = IPv6
+ static const mDNSOpaque16 ARP_hrd_eth = { { 0x00, 0x01 } }; // Hardware address space (Ethernet = 1)
+ static const mDNSOpaque16 ARP_pro_ip = { { 0x08, 0x00 } }; // Protocol address space (IP = 0x0800)
+
+ // Note: BPF guarantees that the NETWORK LAYER header will be word aligned, not the link-layer header.
+ // In other words, we can safely assume that pkt below (ARP, IPv4 or IPv6) is properly word aligned,
+ // but if pkt is 4-byte aligned, that necessarily means that eth CANNOT also be 4-byte aligned
+ // since it points to a an address 14 bytes before pkt.
+ const EthernetHeader *const eth = (const EthernetHeader *)p;
+ const NetworkLayerPacket *const pkt = (const NetworkLayerPacket *)(eth+1);
+ mDNSAddr src, dst;
+ #define RequiredCapLen(P) ((P)==0x01 ? 4 : (P)==0x06 ? 20 : (P)==0x11 ? 8 : (P)==0x3A ? 24 : 0)
+
+ // Is ARP? Length must be at least 14 + 28 = 42 bytes
+ if (end >= p+42 && mDNSSameOpaque16(eth->ethertype, Ethertype_ARP) && mDNSSameOpaque16(pkt->arp.hrd, ARP_hrd_eth) && mDNSSameOpaque16(pkt->arp.pro, ARP_pro_ip))
+ mDNSCoreReceiveRawARP(m, &pkt->arp, InterfaceID);
+ // Is IPv4 with zero fragmentation offset? Length must be at least 14 + 20 = 34 bytes
+ else if (end >= p+34 && mDNSSameOpaque16(eth->ethertype, Ethertype_IPv4) && (pkt->v4.flagsfrags.b[0] & 0x1F) == 0 && pkt->v4.flagsfrags.b[1] == 0)
+ {
+ const mDNSu8 *const trans = p + 14 + (pkt->v4.vlen & 0xF) * 4;
+ debugf("Got IPv4 %02X from %.4a to %.4a", pkt->v4.protocol, &pkt->v4.src, &pkt->v4.dst);
+ src.type = mDNSAddrType_IPv4; src.ip.v4 = pkt->v4.src;
+ dst.type = mDNSAddrType_IPv4; dst.ip.v4 = pkt->v4.dst;
+ if (end >= trans + RequiredCapLen(pkt->v4.protocol))
+ mDNSCoreReceiveRawTransportPacket(m, ð->src, &src, &dst, pkt->v4.protocol, p, (TransportLayerPacket*)trans, end, InterfaceID, 0);
+ }
+ // Is IPv6? Length must be at least 14 + 28 = 42 bytes
+ else if (end >= p+54 && mDNSSameOpaque16(eth->ethertype, Ethertype_IPv6))
+ {
+ const mDNSu8 *const trans = p + 54;
+ debugf("Got IPv6 %02X from %.16a to %.16a", pkt->v6.pro, &pkt->v6.src, &pkt->v6.dst);
+ src.type = mDNSAddrType_IPv6; src.ip.v6 = pkt->v6.src;
+ dst.type = mDNSAddrType_IPv6; dst.ip.v6 = pkt->v6.dst;
+ if (end >= trans + RequiredCapLen(pkt->v6.pro))
+ mDNSCoreReceiveRawTransportPacket(m, ð->src, &src, &dst, pkt->v6.pro, p, (TransportLayerPacket*)trans, end, InterfaceID,
+ (mDNSu16)pkt->bytes[4] << 8 | pkt->bytes[5]);
+ }
+}
mDNSlocal void ConstructSleepProxyServerName(mDNS *const m, domainlabel *name)
- {
- name->c[0] = (mDNSu8)mDNS_snprintf((char*)name->c+1, 62, "%d-%d-%d-%d %#s",
- m->SPSType, m->SPSPortability, m->SPSMarginalPower, m->SPSTotalPower, &m->nicelabel);
- }
+{
+ name->c[0] = (mDNSu8)mDNS_snprintf((char*)name->c+1, 62, "%d-%d-%d-%d.%d %#s",
+ m->SPSType, m->SPSPortability, m->SPSMarginalPower, m->SPSTotalPower, m->SPSFeatureFlags, &m->nicelabel);
+}
+#ifndef SPC_DISABLED
mDNSlocal void SleepProxyServerCallback(mDNS *const m, ServiceRecordSet *const srs, mStatus result)
- {
- if (result == mStatus_NameConflict)
- mDNS_RenameAndReregisterService(m, srs, mDNSNULL);
- else if (result == mStatus_MemFree)
- {
- if (m->SleepState)
- m->SPSState = 3;
- else
- {
- m->SPSState = (mDNSu8)(m->SPSSocket != mDNSNULL);
- if (m->SPSState)
- {
- domainlabel name;
- ConstructSleepProxyServerName(m, &name);
- mDNS_RegisterService(m, srs,
- &name, &SleepProxyServiceType, &localdomain,
- mDNSNULL, m->SPSSocket->port, // Host, port
- (mDNSu8 *)"", 1, // TXT data, length
- mDNSNULL, 0, // Subtypes (none)
- mDNSInterface_Any, // Interface ID
- SleepProxyServerCallback, mDNSNULL, 0); // Callback, context, flags
- }
- LogSPS("Sleep Proxy Server %#s %s", srs->RR_SRV.resrec.name->c, m->SPSState ? "started" : "stopped");
- }
- }
- }
+{
+ if (result == mStatus_NameConflict)
+ mDNS_RenameAndReregisterService(m, srs, mDNSNULL);
+ else if (result == mStatus_MemFree)
+ {
+ if (m->SleepState)
+ m->SPSState = 3;
+ else
+ {
+ m->SPSState = (mDNSu8)(m->SPSSocket != mDNSNULL);
+ if (m->SPSState)
+ {
+ domainlabel name;
+ ConstructSleepProxyServerName(m, &name);
+ mDNS_RegisterService(m, srs,
+ &name, &SleepProxyServiceType, &localdomain,
+ mDNSNULL, m->SPSSocket->port, // Host, port
+ (mDNSu8 *)"", 1, // TXT data, length
+ mDNSNULL, 0, // Subtypes (none)
+ mDNSInterface_Any, // Interface ID
+ SleepProxyServerCallback, mDNSNULL, 0); // Callback, context, flags
+ }
+ LogSPS("Sleep Proxy Server %#s %s", srs->RR_SRV.resrec.name->c, m->SPSState ? "started" : "stopped");
+ }
+ }
+}
+#endif
// Called with lock held
-mDNSexport void mDNSCoreBeSleepProxyServer_internal(mDNS *const m, mDNSu8 sps, mDNSu8 port, mDNSu8 marginalpower, mDNSu8 totpower)
- {
- // This routine uses mDNS_DeregisterService and calls SleepProxyServerCallback, so we execute in user callback context
- mDNS_DropLockBeforeCallback();
-
- // If turning off SPS, close our socket
- // (Do this first, BEFORE calling mDNS_DeregisterService below)
- if (!sps && m->SPSSocket) { mDNSPlatformUDPClose(m->SPSSocket); m->SPSSocket = mDNSNULL; }
-
- // If turning off, or changing type, deregister old name
- if (m->SPSState == 1 && sps != m->SPSType)
- { m->SPSState = 2; mDNS_DeregisterService_drt(m, &m->SPSRecords, sps ? mDNS_Dereg_rapid : mDNS_Dereg_normal); }
-
- // Record our new SPS parameters
- m->SPSType = sps;
- m->SPSPortability = port;
- m->SPSMarginalPower = marginalpower;
- m->SPSTotalPower = totpower;
-
- // If turning on, open socket and advertise service
- if (sps)
- {
- if (!m->SPSSocket)
- {
- m->SPSSocket = mDNSPlatformUDPSocket(m, zeroIPPort);
- if (!m->SPSSocket) { LogMsg("mDNSCoreBeSleepProxyServer: Failed to allocate SPSSocket"); goto fail; }
- }
- if (m->SPSState == 0) SleepProxyServerCallback(m, &m->SPSRecords, mStatus_MemFree);
- }
- else if (m->SPSState)
- {
- LogSPS("mDNSCoreBeSleepProxyServer turning off from state %d; will wake clients", m->SPSState);
- m->NextScheduledSPS = m->timenow;
- }
+mDNSexport void mDNSCoreBeSleepProxyServer_internal(mDNS *const m, mDNSu8 sps, mDNSu8 port, mDNSu8 marginalpower, mDNSu8 totpower, mDNSu8 features)
+{
+ // This routine uses mDNS_DeregisterService and calls SleepProxyServerCallback, so we execute in user callback context
+ mDNS_DropLockBeforeCallback();
+
+ // If turning off SPS, close our socket
+ // (Do this first, BEFORE calling mDNS_DeregisterService below)
+ if (!sps && m->SPSSocket) { mDNSPlatformUDPClose(m->SPSSocket); m->SPSSocket = mDNSNULL; }
+
+ // If turning off, or changing type, deregister old name
+#ifndef SPC_DISABLED
+ if (m->SPSState == 1 && sps != m->SPSType)
+ { m->SPSState = 2; mDNS_DeregisterService_drt(m, &m->SPSRecords, sps ? mDNS_Dereg_rapid : mDNS_Dereg_normal); }
+#endif // SPC_DISABLED
+
+ // Record our new SPS parameters
+ m->SPSType = sps;
+ m->SPSPortability = port;
+ m->SPSMarginalPower = marginalpower;
+ m->SPSTotalPower = totpower;
+ m->SPSFeatureFlags = features;
+ // If turning on, open socket and advertise service
+ if (sps)
+ {
+ if (!m->SPSSocket)
+ {
+ m->SPSSocket = mDNSPlatformUDPSocket(m, zeroIPPort);
+ if (!m->SPSSocket) { LogMsg("mDNSCoreBeSleepProxyServer: Failed to allocate SPSSocket"); goto fail; }
+ }
+#ifndef SPC_DISABLED
+ if (m->SPSState == 0) SleepProxyServerCallback(m, &m->SPSRecords, mStatus_MemFree);
+#endif // SPC_DISABLED
+ }
+ else if (m->SPSState)
+ {
+ LogSPS("mDNSCoreBeSleepProxyServer turning off from state %d; will wake clients", m->SPSState);
+ m->NextScheduledSPS = m->timenow;
+ }
fail:
- mDNS_ReclaimLockAfterCallback();
- }
+ mDNS_ReclaimLockAfterCallback();
+}
// ***************************************************************************
#if COMPILER_LIKES_PRAGMA_MARK
#endif
mDNSlocal void mDNS_GrowCache_internal(mDNS *const m, CacheEntity *storage, mDNSu32 numrecords)
- {
- if (storage && numrecords)
- {
- mDNSu32 i;
- debugf("Adding cache storage for %d more records (%d bytes)", numrecords, numrecords*sizeof(CacheEntity));
- for (i=0; i<numrecords; i++) storage[i].next = &storage[i+1];
- storage[numrecords-1].next = m->rrcache_free;
- m->rrcache_free = storage;
- m->rrcache_size += numrecords;
- }
- }
+{
+ if (storage && numrecords)
+ {
+ mDNSu32 i;
+ debugf("Adding cache storage for %d more records (%d bytes)", numrecords, numrecords*sizeof(CacheEntity));
+ for (i=0; i<numrecords; i++) storage[i].next = &storage[i+1];
+ storage[numrecords-1].next = m->rrcache_free;
+ m->rrcache_free = storage;
+ m->rrcache_size += numrecords;
+ }
+}
mDNSexport void mDNS_GrowCache(mDNS *const m, CacheEntity *storage, mDNSu32 numrecords)
- {
- mDNS_Lock(m);
- mDNS_GrowCache_internal(m, storage, numrecords);
- mDNS_Unlock(m);
- }
+{
+ mDNS_Lock(m);
+ mDNS_GrowCache_internal(m, storage, numrecords);
+ mDNS_Unlock(m);
+}
mDNSexport mStatus mDNS_Init(mDNS *const m, mDNS_PlatformSupport *const p,
- CacheEntity *rrcachestorage, mDNSu32 rrcachesize,
- mDNSBool AdvertiseLocalAddresses, mDNSCallback *Callback, void *Context)
- {
- mDNSu32 slot;
- mDNSs32 timenow;
- mStatus result;
-
- if (!rrcachestorage) rrcachesize = 0;
-
- m->p = p;
- m->KnownBugs = 0;
- m->CanReceiveUnicastOn5353 = mDNSfalse; // Assume we can't receive unicasts on 5353, unless platform layer tells us otherwise
- m->AdvertiseLocalAddresses = AdvertiseLocalAddresses;
- m->DivertMulticastAdvertisements = mDNSfalse;
- m->mDNSPlatformStatus = mStatus_Waiting;
- m->UnicastPort4 = zeroIPPort;
- m->UnicastPort6 = zeroIPPort;
- m->PrimaryMAC = zeroEthAddr;
- m->MainCallback = Callback;
- m->MainContext = Context;
- m->rec.r.resrec.RecordType = 0;
-
- // For debugging: To catch and report locking failures
- m->mDNS_busy = 0;
- m->mDNS_reentrancy = 0;
- m->ShutdownTime = 0;
- m->lock_rrcache = 0;
- m->lock_Questions = 0;
- m->lock_Records = 0;
-
- // Task Scheduling variables
- result = mDNSPlatformTimeInit();
- if (result != mStatus_NoError) return(result);
- m->timenow_adjust = (mDNSs32)mDNSRandom(0xFFFFFFFF);
- timenow = mDNS_TimeNow_NoLock(m);
-
- m->timenow = 0; // MUST only be set within mDNS_Lock/mDNS_Unlock section
- m->timenow_last = timenow;
- m->NextScheduledEvent = timenow;
- m->SuppressSending = timenow;
- m->NextCacheCheck = timenow + 0x78000000;
- m->NextScheduledQuery = timenow + 0x78000000;
- m->NextScheduledProbe = timenow + 0x78000000;
- m->NextScheduledResponse = timenow + 0x78000000;
- m->NextScheduledNATOp = timenow + 0x78000000;
- m->NextScheduledSPS = timenow + 0x78000000;
- m->NextScheduledStopTime = timenow + 0x78000000;
- m->RandomQueryDelay = 0;
- m->RandomReconfirmDelay = 0;
- m->PktNum = 0;
- m->LocalRemoveEvents = mDNSfalse;
- m->SleepState = SleepState_Awake;
- m->SleepSeqNum = 0;
- m->SystemWakeOnLANEnabled = mDNSfalse;
- m->AnnounceOwner = NonZeroTime(timenow + 60 * mDNSPlatformOneSecond);
- m->DelaySleep = 0;
- m->SleepLimit = 0;
-
- // These fields only required for mDNS Searcher...
- m->Questions = mDNSNULL;
- m->NewQuestions = mDNSNULL;
- m->CurrentQuestion = mDNSNULL;
- m->LocalOnlyQuestions = mDNSNULL;
- m->NewLocalOnlyQuestions = mDNSNULL;
- m->RestartQuestion = mDNSNULL;
- m->rrcache_size = 0;
- m->rrcache_totalused = 0;
- m->rrcache_active = 0;
- m->rrcache_report = 10;
- m->rrcache_free = mDNSNULL;
-
- for (slot = 0; slot < CACHE_HASH_SLOTS; slot++)
- {
- m->rrcache_hash[slot] = mDNSNULL;
- m->rrcache_nextcheck[slot] = timenow + 0x78000000;;
- }
-
- mDNS_GrowCache_internal(m, rrcachestorage, rrcachesize);
- m->rrauth.rrauth_free = mDNSNULL;
-
- for (slot = 0; slot < AUTH_HASH_SLOTS; slot++)
- m->rrauth.rrauth_hash[slot] = mDNSNULL;
-
- // Fields below only required for mDNS Responder...
- m->hostlabel.c[0] = 0;
- m->nicelabel.c[0] = 0;
- m->MulticastHostname.c[0] = 0;
- m->HIHardware.c[0] = 0;
- m->HISoftware.c[0] = 0;
- m->ResourceRecords = mDNSNULL;
- m->DuplicateRecords = mDNSNULL;
- m->NewLocalRecords = mDNSNULL;
- m->NewLocalOnlyRecords = mDNSfalse;
- m->CurrentRecord = mDNSNULL;
- m->HostInterfaces = mDNSNULL;
- m->ProbeFailTime = 0;
- m->NumFailedProbes = 0;
- m->SuppressProbes = 0;
+ CacheEntity *rrcachestorage, mDNSu32 rrcachesize,
+ mDNSBool AdvertiseLocalAddresses, mDNSCallback *Callback, void *Context)
+{
+ mDNSu32 slot;
+ mDNSs32 timenow;
+ mStatus result;
+
+ if (!rrcachestorage) rrcachesize = 0;
+
+ m->p = p;
+ m->CanReceiveUnicastOn5353 = mDNSfalse; // Assume we can't receive unicasts on 5353, unless platform layer tells us otherwise
+ m->AdvertiseLocalAddresses = AdvertiseLocalAddresses;
+ m->DivertMulticastAdvertisements = mDNSfalse;
+ m->mDNSPlatformStatus = mStatus_Waiting;
+ m->UnicastPort4 = zeroIPPort;
+ m->UnicastPort6 = zeroIPPort;
+ m->PrimaryMAC = zeroEthAddr;
+ m->MainCallback = Callback;
+ m->MainContext = Context;
+ m->rec.r.resrec.RecordType = 0;
+ m->rec.r.resrec.AnonInfo = mDNSNULL;
+
+ // For debugging: To catch and report locking failures
+ m->mDNS_busy = 0;
+ m->mDNS_reentrancy = 0;
+ m->ShutdownTime = 0;
+ m->lock_rrcache = 0;
+ m->lock_Questions = 0;
+ m->lock_Records = 0;
+
+ // Task Scheduling variables
+ result = mDNSPlatformTimeInit();
+ if (result != mStatus_NoError) return(result);
+ m->timenow_adjust = (mDNSs32)mDNSRandom(0xFFFFFFFF);
+ timenow = mDNS_TimeNow_NoLock(m);
+
+ m->timenow = 0; // MUST only be set within mDNS_Lock/mDNS_Unlock section
+ m->timenow_last = timenow;
+ m->NextScheduledEvent = timenow;
+ m->SuppressSending = timenow;
+ m->NextCacheCheck = timenow + 0x78000000;
+ m->NextScheduledQuery = timenow + 0x78000000;
+ m->NextScheduledProbe = timenow + 0x78000000;
+ m->NextScheduledResponse = timenow + 0x78000000;
+ m->NextScheduledNATOp = timenow + 0x78000000;
+ m->NextScheduledSPS = timenow + 0x78000000;
+ m->NextScheduledKA = timenow + 0x78000000;
+ m->NextScheduledStopTime = timenow + 0x78000000;
+ m->RandomQueryDelay = 0;
+ m->RandomReconfirmDelay = 0;
+ m->PktNum = 0;
+ m->MPktNum = 0;
+ m->LocalRemoveEvents = mDNSfalse;
+ m->SleepState = SleepState_Awake;
+ m->SleepSeqNum = 0;
+ m->SystemWakeOnLANEnabled = mDNSfalse;
+ m->AnnounceOwner = NonZeroTime(timenow + 60 * mDNSPlatformOneSecond);
+ m->DelaySleep = 0;
+ m->SleepLimit = 0;
+
+#if APPLE_OSX_mDNSResponder
+ m->StatStartTime = mDNSPlatformUTC();
+ m->NextStatLogTime = m->StatStartTime + kDefaultNextStatsticsLogTime;
+ m->ActiveStatTime = 0;
+ m->UnicastPacketsSent = 0;
+ m->MulticastPacketsSent = 0;
+ m->RemoteSubnet = 0;
+#endif // APPLE_OSX_mDNSResponder
+
+ // These fields only required for mDNS Searcher...
+ m->Questions = mDNSNULL;
+ m->NewQuestions = mDNSNULL;
+ m->CurrentQuestion = mDNSNULL;
+ m->LocalOnlyQuestions = mDNSNULL;
+ m->NewLocalOnlyQuestions = mDNSNULL;
+ m->RestartQuestion = mDNSNULL;
+ m->ValidationQuestion = mDNSNULL;
+ m->rrcache_size = 0;
+ m->rrcache_totalused = 0;
+ m->rrcache_active = 0;
+ m->rrcache_report = 10;
+ m->rrcache_free = mDNSNULL;
+
+ for (slot = 0; slot < CACHE_HASH_SLOTS; slot++)
+ {
+ m->rrcache_hash[slot] = mDNSNULL;
+ m->rrcache_nextcheck[slot] = timenow + 0x78000000;;
+ }
+
+ mDNS_GrowCache_internal(m, rrcachestorage, rrcachesize);
+ m->rrauth.rrauth_free = mDNSNULL;
+
+ for (slot = 0; slot < AUTH_HASH_SLOTS; slot++)
+ m->rrauth.rrauth_hash[slot] = mDNSNULL;
+
+ // Fields below only required for mDNS Responder...
+ m->hostlabel.c[0] = 0;
+ m->nicelabel.c[0] = 0;
+ m->MulticastHostname.c[0] = 0;
+ m->HIHardware.c[0] = 0;
+ m->HISoftware.c[0] = 0;
+ m->ResourceRecords = mDNSNULL;
+ m->DuplicateRecords = mDNSNULL;
+ m->NewLocalRecords = mDNSNULL;
+ m->NewLocalOnlyRecords = mDNSfalse;
+ m->CurrentRecord = mDNSNULL;
+ m->HostInterfaces = mDNSNULL;
+ m->ProbeFailTime = 0;
+ m->NumFailedProbes = 0;
+ m->SuppressProbes = 0;
#ifndef UNICAST_DISABLED
- m->NextuDNSEvent = timenow + 0x78000000;
- m->NextSRVUpdate = timenow + 0x78000000;
-
- m->DNSServers = mDNSNULL;
-
- m->Router = zeroAddr;
- m->AdvertisedV4 = zeroAddr;
- m->AdvertisedV6 = zeroAddr;
-
- m->AuthInfoList = mDNSNULL;
-
- m->ReverseMap.ThisQInterval = -1;
- m->StaticHostname.c[0] = 0;
- m->FQDN.c[0] = 0;
- m->Hostnames = mDNSNULL;
- m->AutoTunnelHostAddr.b[0] = 0;
- m->AutoTunnelHostAddrActive = mDNSfalse;
- m->AutoTunnelLabel.c[0] = 0;
-
- m->StartWABQueries = mDNSfalse;
- m->RegisterAutoTunnel6 = mDNStrue;
-
- // NAT traversal fields
- m->NATTraversals = mDNSNULL;
- m->CurrentNATTraversal = mDNSNULL;
- m->retryIntervalGetAddr = 0; // delta between time sent and retry
- m->retryGetAddr = timenow + 0x78000000; // absolute time when we retry
- m->ExternalAddress = zerov4Addr;
-
- m->NATMcastRecvskt = mDNSNULL;
- m->LastNATupseconds = 0;
- m->LastNATReplyLocalTime = timenow;
- m->LastNATMapResultCode = NATErr_None;
-
- m->UPnPInterfaceID = 0;
- m->SSDPSocket = mDNSNULL;
- m->SSDPWANPPPConnection = mDNSfalse;
- m->UPnPRouterPort = zeroIPPort;
- m->UPnPSOAPPort = zeroIPPort;
- m->UPnPRouterURL = mDNSNULL;
- m->UPnPWANPPPConnection = mDNSfalse;
- m->UPnPSOAPURL = mDNSNULL;
- m->UPnPRouterAddressString = mDNSNULL;
- m->UPnPSOAPAddressString = mDNSNULL;
- m->SPSType = 0;
- m->SPSPortability = 0;
- m->SPSMarginalPower = 0;
- m->SPSTotalPower = 0;
- m->SPSState = 0;
- m->SPSProxyListChanged = mDNSNULL;
- m->SPSSocket = mDNSNULL;
- m->SPSBrowseCallback = mDNSNULL;
- m->ProxyRecords = 0;
+ m->NextuDNSEvent = timenow + 0x78000000;
+ m->NextSRVUpdate = timenow + 0x78000000;
+
+ m->DNSServers = mDNSNULL;
+
+ m->Router = zeroAddr;
+ m->AdvertisedV4 = zeroAddr;
+ m->AdvertisedV6 = zeroAddr;
+
+ m->AuthInfoList = mDNSNULL;
+
+ m->ReverseMap.ThisQInterval = -1;
+ m->StaticHostname.c[0] = 0;
+ m->FQDN.c[0] = 0;
+ m->Hostnames = mDNSNULL;
+ m->AutoTunnelNAT.clientContext = mDNSNULL;
+
+ m->WABBrowseQueriesCount = 0;
+ m->WABLBrowseQueriesCount = 0;
+ m->WABRegQueriesCount = 0;
+#if !TARGET_OS_EMBEDDED
+ m->mDNSOppCaching = mDNStrue;
+#else
+ m->mDNSOppCaching = mDNSfalse;
+#endif
+ m->AutoTargetServices = 0;
+
+ // NAT traversal fields
+ m->LLQNAT.clientCallback = mDNSNULL;
+ m->LLQNAT.clientContext = mDNSNULL;
+ m->NATTraversals = mDNSNULL;
+ m->CurrentNATTraversal = mDNSNULL;
+ m->retryIntervalGetAddr = 0; // delta between time sent and retry
+ m->retryGetAddr = timenow + 0x78000000; // absolute time when we retry
+ m->ExtAddress = zerov4Addr;
+ m->PCPNonce[0] = mDNSRandom(-1);
+ m->PCPNonce[1] = mDNSRandom(-1);
+ m->PCPNonce[2] = mDNSRandom(-1);
+
+ m->NATMcastRecvskt = mDNSNULL;
+ m->LastNATupseconds = 0;
+ m->LastNATReplyLocalTime = timenow;
+ m->LastNATMapResultCode = NATErr_None;
+
+ m->UPnPInterfaceID = 0;
+ m->SSDPSocket = mDNSNULL;
+ m->SSDPWANPPPConnection = mDNSfalse;
+ m->UPnPRouterPort = zeroIPPort;
+ m->UPnPSOAPPort = zeroIPPort;
+ m->UPnPRouterURL = mDNSNULL;
+ m->UPnPWANPPPConnection = mDNSfalse;
+ m->UPnPSOAPURL = mDNSNULL;
+ m->UPnPRouterAddressString = mDNSNULL;
+ m->UPnPSOAPAddressString = mDNSNULL;
+ m->SPSType = 0;
+ m->SPSPortability = 0;
+ m->SPSMarginalPower = 0;
+ m->SPSTotalPower = 0;
+ m->SPSFeatureFlags = 0;
+ m->SPSState = 0;
+ m->SPSProxyListChanged = mDNSNULL;
+ m->SPSSocket = mDNSNULL;
+ m->SPSBrowseCallback = mDNSNULL;
+ m->ProxyRecords = 0;
#endif
#if APPLE_OSX_mDNSResponder
- m->TunnelClients = mDNSNULL;
-
-#if ! NO_WCF
- CHECK_WCF_FUNCTION(WCFConnectionNew)
- {
- m->WCF = WCFConnectionNew();
- if (!m->WCF) { LogMsg("WCFConnectionNew failed"); return -1; }
- }
+ m->TunnelClients = mDNSNULL;
+
+#if !NO_WCF
+ CHECK_WCF_FUNCTION(WCFConnectionNew)
+ {
+ m->WCF = WCFConnectionNew();
+ if (!m->WCF) { LogMsg("WCFConnectionNew failed"); return -1; }
+ }
#endif
#endif
- result = mDNSPlatformInit(m);
+ result = mDNSPlatformInit(m);
#ifndef UNICAST_DISABLED
- // It's better to do this *after* the platform layer has set up the
- // interface list and security credentials
- uDNS_SetupDNSConfig(m); // Get initial DNS configuration
+ // It's better to do this *after* the platform layer has set up the
+ // interface list and security credentials
+ uDNS_SetupDNSConfig(m); // Get initial DNS configuration
#endif
- return(result);
- }
+ return(result);
+}
mDNSexport void mDNS_ConfigChanged(mDNS *const m)
- {
- if (m->SPSState == 1)
- {
- domainlabel name, newname;
- domainname type, domain;
- DeconstructServiceName(m->SPSRecords.RR_SRV.resrec.name, &name, &type, &domain);
- ConstructSleepProxyServerName(m, &newname);
- if (!SameDomainLabelCS(name.c, newname.c))
- {
- LogSPS("Renaming SPS from “%#s” to “%#s”", name.c, newname.c);
- // When SleepProxyServerCallback gets the mStatus_MemFree message,
- // it will reregister the service under the new name
- m->SPSState = 2;
- mDNS_DeregisterService_drt(m, &m->SPSRecords, mDNS_Dereg_rapid);
- }
- }
-
- if (m->MainCallback)
- m->MainCallback(m, mStatus_ConfigChanged);
- }
+{
+ if (m->SPSState == 1)
+ {
+ domainlabel name, newname;
+#ifndef SPC_DISABLED
+ domainname type, domain;
+ DeconstructServiceName(m->SPSRecords.RR_SRV.resrec.name, &name, &type, &domain);
+#endif // SPC_DISABLED
+ ConstructSleepProxyServerName(m, &newname);
+ if (!SameDomainLabelCS(name.c, newname.c))
+ {
+ LogSPS("Renaming SPS from “%#s” to “%#s”", name.c, newname.c);
+ // When SleepProxyServerCallback gets the mStatus_MemFree message,
+ // it will reregister the service under the new name
+ m->SPSState = 2;
+#ifndef SPC_DISABLED
+ mDNS_DeregisterService_drt(m, &m->SPSRecords, mDNS_Dereg_rapid);
+#endif // SPC_DISABLED
+ }
+ }
+
+ if (m->MainCallback)
+ m->MainCallback(m, mStatus_ConfigChanged);
+}
mDNSlocal void DynDNSHostNameCallback(mDNS *const m, AuthRecord *const rr, mStatus result)
- {
- (void)m; // unused
- debugf("NameStatusCallback: result %d for registration of name %##s", result, rr->resrec.name->c);
- mDNSPlatformDynDNSHostNameStatusChanged(rr->resrec.name, result);
- }
+{
+ (void)m; // unused
+ debugf("NameStatusCallback: result %d for registration of name %##s", result, rr->resrec.name->c);
+ mDNSPlatformDynDNSHostNameStatusChanged(rr->resrec.name, result);
+}
mDNSlocal void PurgeOrReconfirmCacheRecord(mDNS *const m, CacheRecord *cr, const DNSServer * const ptr, mDNSBool lameduck)
- {
- mDNSBool purge = cr->resrec.RecordType == kDNSRecordTypePacketNegative ||
- cr->resrec.rrtype == kDNSType_A ||
- cr->resrec.rrtype == kDNSType_AAAA ||
- cr->resrec.rrtype == kDNSType_SRV;
-
- (void) lameduck;
- (void) ptr;
- debugf("PurgeOrReconfirmCacheRecord: %s cache record due to %s server %p %#a:%d (%##s): %s",
- purge ? "purging" : "reconfirming",
- lameduck ? "lame duck" : "new",
- ptr, &ptr->addr, mDNSVal16(ptr->port), ptr->domain.c, CRDisplayString(m, cr));
-
- if (purge)
- {
- LogInfo("PurgeorReconfirmCacheRecord: Purging Resourcerecord %s, RecordType %x", CRDisplayString(m, cr), cr->resrec.RecordType);
- mDNS_PurgeCacheResourceRecord(m, cr);
- }
- else
- {
- LogInfo("PurgeorReconfirmCacheRecord: Reconfirming Resourcerecord %s, RecordType %x", CRDisplayString(m, cr), cr->resrec.RecordType);
- mDNS_Reconfirm_internal(m, cr, kDefaultReconfirmTimeForNoAnswer);
- }
- }
-
-mDNSlocal void mDNS_PurgeBeforeResolve(mDNS *const m, DNSQuestion *q)
- {
- const mDNSu32 slot = HashSlot(&q->qname);
- CacheGroup *const cg = CacheGroupForName(m, slot, q->qnamehash, &q->qname);
- CacheRecord *rp;
-
- for (rp = cg ? cg->members : mDNSNULL; rp; rp = rp->next)
- {
- if (SameNameRecordAnswersQuestion(&rp->resrec, q))
- {
- LogInfo("mDNS_PurgeBeforeResolve: Flushing %s", CRDisplayString(m, rp));
- mDNS_PurgeCacheResourceRecord(m, rp);
- }
- }
- }
+{
+ mDNSBool purge = cr->resrec.RecordType == kDNSRecordTypePacketNegative ||
+ cr->resrec.rrtype == kDNSType_A ||
+ cr->resrec.rrtype == kDNSType_AAAA ||
+ cr->resrec.rrtype == kDNSType_SRV;
+
+ (void) lameduck;
+ (void) ptr;
+ debugf("PurgeOrReconfirmCacheRecord: %s cache record due to %s server %p %#a:%d (%##s): %s",
+ purge ? "purging" : "reconfirming",
+ lameduck ? "lame duck" : "new",
+ ptr, &ptr->addr, mDNSVal16(ptr->port), ptr->domain.c, CRDisplayString(m, cr));
+
+ if (purge)
+ {
+ LogInfo("PurgeorReconfirmCacheRecord: Purging Resourcerecord %s, RecordType %x", CRDisplayString(m, cr), cr->resrec.RecordType);
+ mDNS_PurgeCacheResourceRecord(m, cr);
+ }
+ else
+ {
+ LogInfo("PurgeorReconfirmCacheRecord: Reconfirming Resourcerecord %s, RecordType %x", CRDisplayString(m, cr), cr->resrec.RecordType);
+ mDNS_Reconfirm_internal(m, cr, kDefaultReconfirmTimeForNoAnswer);
+ }
+}
+
+mDNSlocal void mDNS_PurgeForQuestion(mDNS *const m, DNSQuestion *q)
+{
+ const mDNSu32 slot = HashSlot(&q->qname);
+ CacheGroup *const cg = CacheGroupForName(m, slot, q->qnamehash, &q->qname);
+ CacheRecord *rp;
+ mDNSu8 validatingResponse = 0;
+
+ // For DNSSEC questions, purge the corresponding RRSIGs also.
+ if (DNSSECQuestion(q))
+ {
+ validatingResponse = q->ValidatingResponse;
+ q->ValidatingResponse = mDNStrue;
+ }
+ for (rp = cg ? cg->members : mDNSNULL; rp; rp = rp->next)
+ {
+ if (SameNameRecordAnswersQuestion(&rp->resrec, q))
+ {
+ LogInfo("mDNS_PurgeForQuestion: Flushing %s", CRDisplayString(m, rp));
+ mDNS_PurgeCacheResourceRecord(m, rp);
+ }
+ }
+ if (DNSSECQuestion(q))
+ {
+ q->ValidatingResponse = validatingResponse;
+ }
+}
+
+// For DNSSEC question, we need the DNSSEC records also. If the cache does not
+// have the DNSSEC records, we need to re-issue the question with EDNS0/DO bit set.
+// Just re-issuing the question for RRSIGs does not work in practice as the response
+// may not contain the RRSIGs whose typeCovered field matches the question's qtype.
+//
+// For negative responses, we need the NSECs to prove the non-existence. If we don't
+// have the cached NSECs, purge them. For positive responses, if we don't have the
+// RRSIGs and if we have not already issued the question with EDNS0/DO bit set, purge
+// them.
+mDNSlocal void CheckForDNSSECRecords(mDNS *const m, DNSQuestion *q)
+{
+ const mDNSu32 slot = HashSlot(&q->qname);
+ CacheGroup *const cg = CacheGroupForName(m, slot, q->qnamehash, &q->qname);
+ CacheRecord *rp;
+
+ for (rp = cg ? cg->members : mDNSNULL; rp; rp = rp->next)
+ {
+ if (SameNameRecordAnswersQuestion(&rp->resrec, q))
+ {
+ if (rp->resrec.RecordType != kDNSRecordTypePacketNegative || !rp->nsec)
+ {
+ if (!rp->CRDNSSECQuestion)
+ {
+ LogInfo("CheckForDNSSECRecords: Flushing %s", CRDisplayString(m, rp));
+ mDNS_PurgeCacheResourceRecord(m, rp);
+ }
+ }
+ }
+ }
+}
// Check for a positive unicast response to the question but with qtype
mDNSexport mDNSBool mDNS_CheckForCacheRecord(mDNS *const m, DNSQuestion *q, mDNSu16 qtype)
- {
- DNSQuestion question;
- const mDNSu32 slot = HashSlot(&q->qname);
- CacheGroup *const cg = CacheGroupForName(m, slot, q->qnamehash, &q->qname);
- CacheRecord *rp;
-
- // Create an identical question but with qtype
- mDNS_SetupQuestion(&question, q->InterfaceID, &q->qname, qtype, mDNSNULL, mDNSNULL);
- question.qDNSServer = q->qDNSServer;
-
- for (rp = cg ? cg->members : mDNSNULL; rp; rp = rp->next)
- {
- if (!rp->resrec.InterfaceID && rp->resrec.RecordType != kDNSRecordTypePacketNegative &&
- SameNameRecordAnswersQuestion(&rp->resrec, &question))
- {
- LogInfo("mDNS_CheckForCacheRecord: Found %s", CRDisplayString(m, rp));
- return mDNStrue;
- }
- }
- return mDNSfalse;
- }
-
-mDNSlocal void CacheRecordResetDNSServer(mDNS *const m, DNSQuestion *q, DNSServer *new)
- {
- const mDNSu32 slot = HashSlot(&q->qname);
- CacheGroup *const cg = CacheGroupForName(m, slot, q->qnamehash, &q->qname);
- CacheRecord *rp;
- mDNSBool found = mDNSfalse;
- mDNSBool foundNew = mDNSfalse;
- DNSServer *old = q->qDNSServer;
- mDNSBool newQuestion = IsQuestionNew(m, q);
- DNSQuestion *qptr;
-
- // This function is called when the DNSServer is updated to the new question. There may already be
- // some cache entries matching the old DNSServer and/or new DNSServer. There are four cases. In the
- // following table, "Yes" denotes that a cache entry was found for old/new DNSServer.
- //
- // old DNSServer new DNSServer
- //
- // Case 1 Yes Yes
- // Case 2 No Yes
- // Case 3 Yes No
- // Case 4 No No
- //
- // Case 1: There are cache entries for both old and new DNSServer. We handle this case by simply
- // expiring the old Cache entries, deliver a RMV event (if an ADD event was delivered before)
- // followed by the ADD event of the cache entries corresponding to the new server. This
- // case happens when we pick a DNSServer, issue a query and get a valid response and create
- // cache entries after which it stops responding. Another query (non-duplicate) picks a different
- // DNSServer and creates identical cache entries (perhaps through records in Additional records).
- // Now if the first one expires and tries to pick the new DNSServer (the original DNSServer
- // is not responding) we will find cache entries corresponding to both DNSServers.
- //
- // Case 2: There are no cache entries for the old DNSServer but there are some for the new DNSServer.
- // This means we should deliver an ADD event. Normally ADD events are delivered by
- // AnswerNewQuestion if it is a new question. So, we check to see if it is a new question
- // and if so, leave it to AnswerNewQuestion to deliver it. Otherwise, we use
- // AnswerQuestionsForDNSServerChanges to deliver the ADD event. This case happens when a
- // question picks a DNS server for which AnswerNewQuestion could not deliver an answer even
- // though there were potential cache entries but DNSServer did not match. Now when we
- // pick a new DNSServer, those cache entries may answer this question.
- //
- // Case 3: There are the cache entries for the old DNSServer but none for the new. We just move
- // the old cache entries to point to the new DNSServer and the caller is expected to
- // do a purge or reconfirm to delete or validate the RDATA. We don't need to do anything
- // special for delivering ADD events, as it should have been done/will be done by
- // AnswerNewQuestion. This case happens when we picked a DNSServer, sent the query and
- // got a response and the cache is expired now and we are reissuing the question but the
- // original DNSServer does not respond.
- //
- // Case 4: There are no cache entries either for the old or for the new DNSServer. There is nothing
- // much we can do here.
- //
- // Case 2 and 3 are the most common while case 4 is possible when no DNSServers are working. Case 1
- // is relatively less likely to happen in practice
-
- // Temporarily set the DNSServer to look for the matching records for the new DNSServer.
- q->qDNSServer = new;
- for (rp = cg ? cg->members : mDNSNULL; rp; rp = rp->next)
- {
- if (SameNameRecordAnswersQuestion(&rp->resrec, q))
- {
- LogInfo("CacheRecordResetDNSServer: Found cache record %##s for new DNSServer address: %#a", rp->resrec.name->c,
- (rp->resrec.rDNSServer != mDNSNULL ? &rp->resrec.rDNSServer->addr : mDNSNULL));
- foundNew = mDNStrue;
- break;
- }
- }
- q->qDNSServer = old;
-
- for (rp = cg ? cg->members : mDNSNULL; rp; rp = rp->next)
- {
- if (SameNameRecordAnswersQuestion(&rp->resrec, q))
- {
- // Case1
- found = mDNStrue;
- if (foundNew)
- {
- LogInfo("CacheRecordResetDNSServer: Flushing Resourcerecord %##s, before:%#a, after:%#a", rp->resrec.name->c,
- (rp->resrec.rDNSServer != mDNSNULL ? &rp->resrec.rDNSServer->addr : mDNSNULL),
- (new != mDNSNULL ? &new->addr : mDNSNULL));
- mDNS_PurgeCacheResourceRecord(m, rp);
- if (newQuestion)
- {
- // "q" is not a duplicate question. If it is a newQuestion, then the CRActiveQuestion can't be
- // possibly set as it is set only when we deliver the ADD event to the question.
- if (rp->CRActiveQuestion != mDNSNULL)
- {
- LogMsg("CacheRecordResetDNSServer: ERROR!!: CRActiveQuestion %p set, current question %p, name %##s", rp->CRActiveQuestion, q, q->qname.c);
- rp->CRActiveQuestion = mDNSNULL;
- }
- // if this is a new question, then we never delivered an ADD yet, so don't deliver the RMV.
- continue;
- }
- }
- LogInfo("CacheRecordResetDNSServer: resetting cache record %##s DNSServer address before:%#a,"
- " after:%#a, CRActiveQuestion %p", rp->resrec.name->c, (rp->resrec.rDNSServer != mDNSNULL ?
- &rp->resrec.rDNSServer->addr : mDNSNULL), (new != mDNSNULL ? &new->addr : mDNSNULL),
- rp->CRActiveQuestion);
- // Though we set it to the new DNS server, the caller is *assumed* to do either a purge
- // or reconfirm or send out questions to the "new" server to verify whether the cached
- // RDATA is valid
- rp->resrec.rDNSServer = new;
- }
- }
-
- // Case 1 and Case 2
- if ((found && foundNew) || (!found && foundNew))
- {
- if (newQuestion)
- LogInfo("CacheRecordResetDNSServer: deliverAddEvents not set for question %p %##s (%s)", q, q->qname.c, DNSTypeName(q->qtype));
- else if (QuerySuppressed(q))
- LogInfo("CacheRecordResetDNSServer: deliverAddEvents not set for suppressed question %p %##s (%s)", q, q->qname.c, DNSTypeName(q->qtype));
- else
- {
- LogInfo("CacheRecordResetDNSServer: deliverAddEvents set for %p %##s (%s)", q, q->qname.c, DNSTypeName(q->qtype));
- q->deliverAddEvents = mDNStrue;
- for (qptr = q->next; qptr; qptr = qptr->next)
- if (qptr->DuplicateOf == q) qptr->deliverAddEvents = mDNStrue;
- }
- return;
- }
-
- // Case 3 and Case 4
- return;
- }
+{
+ DNSQuestion question;
+ const mDNSu32 slot = HashSlot(&q->qname);
+ CacheGroup *const cg = CacheGroupForName(m, slot, q->qnamehash, &q->qname);
+ CacheRecord *rp;
+
+ // Create an identical question but with qtype
+ mDNS_SetupQuestion(&question, q->InterfaceID, &q->qname, qtype, mDNSNULL, mDNSNULL);
+ question.qDNSServer = q->qDNSServer;
+
+ for (rp = cg ? cg->members : mDNSNULL; rp; rp = rp->next)
+ {
+ if (!rp->resrec.InterfaceID && rp->resrec.RecordType != kDNSRecordTypePacketNegative &&
+ SameNameRecordAnswersQuestion(&rp->resrec, &question))
+ {
+ LogInfo("mDNS_CheckForCacheRecord: Found %s", CRDisplayString(m, rp));
+ return mDNStrue;
+ }
+ }
+ return mDNSfalse;
+}
mDNSexport void DNSServerChangeForQuestion(mDNS *const m, DNSQuestion *q, DNSServer *new)
- {
- DNSQuestion *qptr;
-
- // 1. Whenever we change the DNS server, we change the message identifier also so that response
- // from the old server is not accepted as a response from the new server but only messages
- // from the new server are accepted as valid responses. We do it irrespective of whether "new"
- // is NULL or not. It is possible that we send two queries, no responses, pick a new DNS server
- // which is NULL and now the response comes back and will try to penalize the DNS server which
- // is NULL. By setting the messageID here, we will not accept that as a valid response.
-
- q->TargetQID = mDNS_NewMessageID(m);
-
- // 2. Move the old cache records to point them at the new DNSServer so that we can deliver the ADD/RMV events
- // appropriately. At any point in time, we want all the cache records point only to one DNSServer for a given
- // question. "DNSServer" here is the DNSServer object and not the DNS server itself. It is possible to
- // have the same DNS server address in two objects, one scoped and another not scoped. But, the cache is per
- // DNSServer object. By maintaining the question and the cache entries point to the same DNSServer
- // always, the cache maintenance and delivery of ADD/RMV events becomes simpler.
- //
- // CacheRecordResetDNSServer should be called only once for the non-duplicate question as once the cache
- // entries are moved to point to the new DNSServer, we don't need to call it for the duplicate question
- // and it is wrong to call for the duplicate question as it's decision to mark deliverAddevents will be
- // incorrect.
-
- if (q->DuplicateOf)
- LogMsg("DNSServerChangeForQuestion: ERROR: Called for duplicate question %##s", q->qname.c);
- else
- CacheRecordResetDNSServer(m, q, new);
-
- // 3. Make sure all the duplicate questions point to the same DNSServer so that delivery
- // of events for all of them are consistent. Duplicates for a question are always inserted
- // after in the list.
- q->qDNSServer = new;
- for (qptr = q->next ; qptr; qptr = qptr->next)
- {
- if (qptr->DuplicateOf == q) { qptr->validDNSServers = q->validDNSServers; qptr->qDNSServer = new; }
- }
- }
-
+{
+ DNSQuestion *qptr;
+
+ (void) m;
+
+ if (q->DuplicateOf)
+ LogMsg("DNSServerChangeForQuestion: ERROR: Called for duplicate question %##s", q->qname.c);
+
+ // Make sure all the duplicate questions point to the same DNSServer so that delivery
+ // of events for all of them are consistent. Duplicates for a question are always inserted
+ // after in the list.
+ q->qDNSServer = new;
+ for (qptr = q->next ; qptr; qptr = qptr->next)
+ {
+ if (qptr->DuplicateOf == q) { qptr->validDNSServers = q->validDNSServers; qptr->qDNSServer = new; }
+ }
+}
+
+mDNSlocal void SetConfigState(mDNS *const m, mDNSBool delete)
+{
+ McastResolver *mr;
+ DNSServer *ptr;
+
+ if (delete)
+ {
+ for (ptr = m->DNSServers; ptr; ptr = ptr->next)
+ {
+ ptr->penaltyTime = 0;
+ NumUnicastDNSServers--;
+ ptr->flags |= DNSServer_FlagDelete;
+ }
+ // We handle the mcast resolvers here itself as mDNSPlatformSetDNSConfig looks at
+ // mcast resolvers. Today we get both mcast and ucast configuration using the same
+ // API
+ for (mr = m->McastResolvers; mr; mr = mr->next)
+ mr->flags |= McastResolver_FlagDelete;
+ }
+ else
+ {
+ for (ptr = m->DNSServers; ptr; ptr = ptr->next)
+ {
+ ptr->penaltyTime = 0;
+ NumUnicastDNSServers++;
+ ptr->flags &= ~DNSServer_FlagDelete;
+ }
+ for (mr = m->McastResolvers; mr; mr = mr->next)
+ mr->flags &= ~McastResolver_FlagDelete;
+ }
+}
+
mDNSexport mStatus uDNS_SetupDNSConfig(mDNS *const m)
- {
- mDNSu32 slot;
- CacheGroup *cg;
- CacheRecord *cr;
-
- mDNSAddr v4, v6, r;
- domainname fqdn;
- DNSServer *ptr, **p = &m->DNSServers;
- const DNSServer *oldServers = m->DNSServers;
- DNSQuestion *q;
- McastResolver *mr, **mres = &m->McastResolvers;
-
- debugf("uDNS_SetupDNSConfig: entry");
-
- // Let the platform layer get the current DNS information
- // The m->StartWABQueries is set when we get the first domain enumeration query (no need to hit the network
- // with domain enumeration queries until we actually need that information). Even if it is not set, we still
- // need to setup the search domains so that we can append them to queries that need them.
-
- uDNS_SetupSearchDomains(m, m->StartWABQueries ? UDNS_START_WAB_QUERY : 0);
-
- mDNS_Lock(m);
-
- for (ptr = m->DNSServers; ptr; ptr = ptr->next)
- {
- ptr->penaltyTime = 0;
- ptr->flags |= DNSServer_FlagDelete;
- }
-
- // We handle the mcast resolvers here itself as mDNSPlatformSetDNSConfig looks at
- // mcast resolvers. Today we get both mcast and ucast configuration using the same
- // API
- for (mr = m->McastResolvers; mr; mr = mr->next)
- mr->flags |= McastResolver_FlagDelete;
-
- mDNSPlatformSetDNSConfig(m, mDNStrue, mDNSfalse, &fqdn, mDNSNULL, mDNSNULL);
-
- // For now, we just delete the mcast resolvers. We don't deal with cache or
- // questions here. Neither question nor cache point to mcast resolvers. Questions
- // do inherit the timeout values from mcast resolvers. But we don't bother
- // affecting them as they never change.
- while (*mres)
- {
- if (((*mres)->flags & DNSServer_FlagDelete) != 0)
- {
- mr = *mres;
- *mres = (*mres)->next;
- debugf("uDNS_SetupDNSConfig: Deleting mcast resolver %##s", mr, mr->domain.c);
- mDNSPlatformMemFree(mr);
- }
- else
- {
- (*mres)->flags &= ~McastResolver_FlagNew;
- mres = &(*mres)->next;
- }
- }
-
- // Mark the records to be flushed that match a new resolver. We need to do this before
- // we walk the questions below where we change the DNSServer pointer of the cache
- // record
- FORALL_CACHERECORDS(slot, cg, cr)
- {
- if (cr->resrec.InterfaceID) continue;
-
- // We just mark them for purge or reconfirm. We can't affect the DNSServer pointer
- // here as the code below that calls CacheRecordResetDNSServer relies on this
- //
- // The new DNSServer may be a scoped or non-scoped one. We use the active question's
- // InterfaceID for looking up the right DNS server
- ptr = GetServerForName(m, cr->resrec.name, cr->CRActiveQuestion ? cr->CRActiveQuestion->InterfaceID : mDNSNULL);
-
- // Purge or Reconfirm if this cache entry would use the new DNS server
- if (ptr && (ptr != cr->resrec.rDNSServer))
- {
- // As the DNSServers for this cache record is not the same anymore, we don't
- // want any new questions to pick this old value
- if (cr->CRActiveQuestion == mDNSNULL)
- {
- LogInfo("uDNS_SetupDNSConfig: Purging Resourcerecord %s", CRDisplayString(m, cr));
- mDNS_PurgeCacheResourceRecord(m, cr);
- }
- else
- {
- LogInfo("uDNS_SetupDNSConfig: Purging/Reconfirming Resourcerecord %s", CRDisplayString(m, cr));
- PurgeOrReconfirmCacheRecord(m, cr, ptr, mDNSfalse);
- }
- }
- }
- // Update our qDNSServer pointers before we go and free the DNSServer object memory
- for (q = m->Questions; q; q=q->next)
- if (!mDNSOpaque16IsZero(q->TargetQID))
- {
- DNSServer *s, *t;
- DNSQuestion *qptr;
- if (q->DuplicateOf) continue;
- SetValidDNSServers(m, q);
- q->triedAllServersOnce = 0;
- s = GetServerForQuestion(m, q);
- t = q->qDNSServer;
- if (t != s)
- {
- // If DNS Server for this question has changed, reactivate it
- debugf("uDNS_SetupDNSConfig: Updating DNS Server from %p %#a:%d (%##s) to %p %#a:%d (%##s) for %##s (%s)",
- t, t ? &t->addr : mDNSNULL, mDNSVal16(t ? t->port : zeroIPPort), t ? t->domain.c : (mDNSu8*)"",
- s, s ? &s->addr : mDNSNULL, mDNSVal16(s ? s->port : zeroIPPort), s ? s->domain.c : (mDNSu8*)"",
- q->qname.c, DNSTypeName(q->qtype));
-
- // After we reset the DNSServer pointer on the cache records here, three things could happen:
- //
- // 1) The query gets sent out and when the actual response comes back later it is possible
- // that the response has the same RDATA, in which case we update our cache entry.
- // If the response is different, then the entry will expire and a new entry gets added.
- // For the latter case to generate a RMV followed by ADD events, we need to reset the DNS
- // server here to match the question and the cache record.
- //
- // 2) We might have marked the cache entries for purge above and for us to be able to generate the RMV
- // events for the questions, the DNSServer on the question should match the Cache Record
- //
- // 3) We might have marked the cache entries for reconfirm above, for which we send the query out which is
- // the same as the first case above.
-
- DNSServerChangeForQuestion(m, q, s);
- q->unansweredQueries = 0;
- // We still need to pick a new DNSServer for the questions that have been
- // suppressed, but it is wrong to activate the query as DNS server change
- // could not possibly change the status of SuppressUnusable questions
- if (!QuerySuppressed(q))
- {
- debugf("uDNS_SetupDNSConfig: Activating query %p %##s (%s)", q, q->qname.c, DNSTypeName(q->qtype));
- ActivateUnicastQuery(m, q, mDNStrue);
- // ActivateUnicastQuery is called for duplicate questions also as it does something
- // special for AutoTunnel questions
- for (qptr = q->next ; qptr; qptr = qptr->next)
- {
- if (qptr->DuplicateOf == q) ActivateUnicastQuery(m, qptr, mDNStrue);
- }
- }
- }
- else
- {
- debugf("uDNS_SetupDNSConfig: Not Updating DNS server question %p %##s (%s) DNS server %#a:%d %p %d",
- q, q->qname.c, DNSTypeName(q->qtype), t ? &t->addr : mDNSNULL, mDNSVal16(t ? t->port : zeroIPPort), q->DuplicateOf, q->SuppressUnusable);
- for (qptr = q->next ; qptr; qptr = qptr->next)
- if (qptr->DuplicateOf == q) { qptr->validDNSServers = q->validDNSServers; qptr->qDNSServer = q->qDNSServer; }
- }
- }
-
- while (*p)
- {
- if (((*p)->flags & DNSServer_FlagDelete) != 0)
- {
- // Scan our cache, looking for uDNS records that we would have queried this server for.
- // We reconfirm any records that match, because in this world of split DNS, firewalls, etc.
- // different DNS servers can give different answers to the same question.
- ptr = *p;
- FORALL_CACHERECORDS(slot, cg, cr)
- {
- if (cr->resrec.InterfaceID) continue;
- if (cr->resrec.rDNSServer == ptr)
- {
- // If we don't have an active question for this cache record, neither Purge can
- // generate RMV events nor Reconfirm can send queries out. Just set the DNSServer
- // pointer on the record NULL so that we don't point to freed memory (We might dereference
- // DNSServer pointers from resource record for logging purposes).
- //
- // If there is an active question, point to its DNSServer as long as it does not point to the
- // freed one. We already went through the questions above and made them point at either the
- // new server or NULL if there is no server and also affected the cache entries that match
- // this question. Hence, whenever we hit a resource record with a DNSServer that is just
- // about to be deleted, we should never have an active question. The code below just tries to
- // be careful logging messages if we ever hit this case.
-
- if (cr->CRActiveQuestion)
- {
- DNSQuestion *qptr = cr->CRActiveQuestion;
- if (qptr->qDNSServer == mDNSNULL)
- LogMsg("uDNS_SetupDNSConfig: Cache Record %s match: Active question %##s (%s) with DNSServer Address NULL, Server to be deleted %#a",
- CRDisplayString(m, cr), qptr->qname.c, DNSTypeName(qptr->qtype), &ptr->addr);
- else
- LogMsg("uDNS_SetupDNSConfig: Cache Record %s match: Active question %##s (%s) DNSServer Address %#a, Server to be deleted %#a",
- CRDisplayString(m, cr), qptr->qname.c, DNSTypeName(qptr->qtype), &qptr->qDNSServer->addr, &ptr->addr);
-
- if (qptr->qDNSServer == ptr)
- {
- qptr->validDNSServers = zeroOpaque64;
- qptr->qDNSServer = mDNSNULL;
- cr->resrec.rDNSServer = mDNSNULL;
- }
- else
- {
- cr->resrec.rDNSServer = qptr->qDNSServer;
- }
- }
- else
- {
- LogInfo("uDNS_SetupDNSConfig: Cache Record %##s has no Active question, Record's DNSServer Address %#a, Server to be deleted %#a",
- cr->resrec.name, &cr->resrec.rDNSServer->addr, &ptr->addr);
- cr->resrec.rDNSServer = mDNSNULL;
- }
-
- PurgeOrReconfirmCacheRecord(m, cr, ptr, mDNStrue);
- }
- }
- *p = (*p)->next;
- debugf("uDNS_SetupDNSConfig: Deleting server %p %#a:%d (%##s)", ptr, &ptr->addr, mDNSVal16(ptr->port), ptr->domain.c);
- mDNSPlatformMemFree(ptr);
- NumUnicastDNSServers--;
- }
- else
- {
- (*p)->flags &= ~DNSServer_FlagNew;
- p = &(*p)->next;
- }
- }
-
- // If we now have no DNS servers at all and we used to have some, then immediately purge all unicast cache records (including for LLQs).
- // This is important for giving prompt remove events when the user disconnects the Ethernet cable or turns off wireless.
- // Otherwise, stale data lingers for 5-10 seconds, which is not the user-experience people expect from Bonjour.
- // Similarly, if we now have some DNS servers and we used to have none, we want to purge any fake negative results we may have generated.
- if ((m->DNSServers != mDNSNULL) != (oldServers != mDNSNULL))
- {
- int count = 0;
- FORALL_CACHERECORDS(slot, cg, cr) if (!cr->resrec.InterfaceID) { mDNS_PurgeCacheResourceRecord(m, cr); count++; }
- LogInfo("uDNS_SetupDNSConfig: %s available; purged %d unicast DNS records from cache",
- m->DNSServers ? "DNS server became" : "No DNS servers", count);
-
- // Force anything that needs to get zone data to get that information again
- RestartRecordGetZoneData(m);
- }
-
- // Did our FQDN change?
- if (!SameDomainName(&fqdn, &m->FQDN))
- {
- if (m->FQDN.c[0]) mDNS_RemoveDynDNSHostName(m, &m->FQDN);
-
- AssignDomainName(&m->FQDN, &fqdn);
-
- if (m->FQDN.c[0])
- {
- mDNSPlatformDynDNSHostNameStatusChanged(&m->FQDN, 1);
- mDNS_AddDynDNSHostName(m, &m->FQDN, DynDNSHostNameCallback, mDNSNULL);
- }
- }
-
- mDNS_Unlock(m);
-
- // handle router and primary interface changes
- v4 = v6 = r = zeroAddr;
- v4.type = r.type = mDNSAddrType_IPv4;
-
- if (mDNSPlatformGetPrimaryInterface(m, &v4, &v6, &r) == mStatus_NoError && !mDNSv4AddressIsLinkLocal(&v4.ip.v4))
- {
- mDNS_SetPrimaryInterfaceInfo(m,
- !mDNSIPv4AddressIsZero(v4.ip.v4) ? &v4 : mDNSNULL,
- !mDNSIPv6AddressIsZero(v6.ip.v6) ? &v6 : mDNSNULL,
- !mDNSIPv4AddressIsZero(r .ip.v4) ? &r : mDNSNULL);
- }
- else
- {
- mDNS_SetPrimaryInterfaceInfo(m, mDNSNULL, mDNSNULL, mDNSNULL);
- if (m->FQDN.c[0]) mDNSPlatformDynDNSHostNameStatusChanged(&m->FQDN, 1); // Set status to 1 to indicate temporary failure
- }
+{
+ mDNSu32 slot;
+ CacheGroup *cg;
+ CacheRecord *cr;
+ mDNSBool Restart = mDNSfalse;
+ mDNSAddr v4, v6, r;
+ domainname fqdn;
+ DNSServer *ptr, **p = &m->DNSServers;
+ const DNSServer *oldServers = m->DNSServers;
+ DNSQuestion *q;
+ McastResolver *mr, **mres = &m->McastResolvers;
+
+ debugf("uDNS_SetupDNSConfig: entry");
+
+ // Let the platform layer get the current DNS information and setup the WAB queries if needed.
+ uDNS_SetupWABQueries(m);
+
+ mDNS_Lock(m);
+
+ // We need to first mark all the entries to be deleted. If the configuration changed, then
+ // the entries would be undeleted appropriately. Otherwise, we need to clear them.
+ //
+ // Note: The last argument to mDNSPlatformSetDNSConfig is "mDNStrue" which means ack the
+ // configuration. We already processed search domains in uDNS_SetupWABQueries above and
+ // hence we are ready to ack the configuration as this is the last call to mDNSPlatformSetConfig
+ // for the dns configuration change notification.
+ SetConfigState(m, mDNStrue);
+ if (!mDNSPlatformSetDNSConfig(m, mDNStrue, mDNSfalse, &fqdn, mDNSNULL, mDNSNULL, mDNStrue))
+ {
+ SetConfigState(m, mDNSfalse);
+ mDNS_Unlock(m);
+ LogInfo("uDNS_SetupDNSConfig: No configuration change");
+ return mStatus_NoError;
+ }
+
+ // For now, we just delete the mcast resolvers. We don't deal with cache or
+ // questions here. Neither question nor cache point to mcast resolvers. Questions
+ // do inherit the timeout values from mcast resolvers. But we don't bother
+ // affecting them as they never change.
+ while (*mres)
+ {
+ if (((*mres)->flags & DNSServer_FlagDelete) != 0)
+ {
+ mr = *mres;
+ *mres = (*mres)->next;
+ debugf("uDNS_SetupDNSConfig: Deleting mcast resolver %##s", mr, mr->domain.c);
+ mDNSPlatformMemFree(mr);
+ }
+ else
+ {
+ (*mres)->flags &= ~McastResolver_FlagNew;
+ mres = &(*mres)->next;
+ }
+ }
+
+ // Update our qDNSServer pointers before we go and free the DNSServer object memory
+ //
+ // All non-scoped resolvers share the same resGroupID. At no point in time a cache entry using DNSServer
+ // from scoped resolver will be used to answer non-scoped questions and vice versa, as scoped and non-scoped
+ // resolvers don't share the same resGroupID. A few examples to describe the interaction with how we pick
+ // DNSServers and flush the cache.
+ //
+ // - A non-scoped question picks DNSServer X, creates a cache entry with X. If a new resolver gets added later that
+ // is a better match, we pick the new DNSServer for the question and activate the unicast query. We may or may not
+ // flush the cache (See PurgeOrReconfirmCacheRecord). In either case, we don't change the cache record's DNSServer
+ // pointer immediately (qDNSServer and rDNSServer may be different but still share the same resGroupID). If we don't
+ // flush the cache immediately, the record's rDNSServer pointer will be updated (in mDNSCoreReceiveResponse)
+ // later when we get the response. If we purge the cache, we still deliver a RMV when it is purged even though
+ // we don't update the cache record's DNSServer pointer to match the question's DNSSever, as they both point to
+ // the same resGroupID.
+ //
+ // Note: If the new DNSServer comes back with a different response than what we have in the cache, we will deliver a RMV
+ // of the old followed by ADD of the new records.
+ //
+ // - A non-scoped question picks DNSServer X, creates a cache entry with X. If the resolver gets removed later, we will
+ // pick a new DNSServer for the question which may or may not be NULL and set the cache record's pointer to the same
+ // as in question's qDNSServer if the cache record is not flushed. If there is no active question, it will be set to NULL.
+ //
+ // - Two questions scoped and non-scoped for the same name will pick two different DNSServer and will end up creating separate
+ // cache records and as the resGroupID is different, you can't use the cache record from the scoped DNSServer to answer the
+ // non-scoped question and vice versa.
+ //
+ for (q = m->Questions; q; q=q->next)
+ {
+ if (!mDNSOpaque16IsZero(q->TargetQID))
+ {
+ DNSServer *s, *t;
+ DNSQuestion *qptr;
+ if (q->DuplicateOf) continue;
+ SetValidDNSServers(m, q);
+ q->triedAllServersOnce = 0;
+ s = GetServerForQuestion(m, q);
+ t = q->qDNSServer;
+ if (t != s)
+ {
+ mDNSBool old, new;
+ // If DNS Server for this question has changed, reactivate it
+ LogInfo("uDNS_SetupDNSConfig: Updating DNS Server from %#a:%d (%##s) to %#a:%d (%##s) for question %##s (%s) (scope:%p)",
+ t ? &t->addr : mDNSNULL, mDNSVal16(t ? t->port : zeroIPPort), t ? t->domain.c : (mDNSu8*)"",
+ s ? &s->addr : mDNSNULL, mDNSVal16(s ? s->port : zeroIPPort), s ? s->domain.c : (mDNSu8*)"",
+ q->qname.c, DNSTypeName(q->qtype), q->InterfaceID);
+
+ old = q->SuppressQuery;
+ new = ShouldSuppressUnicastQuery(m, q, s);
+ if (old != new)
+ {
+ // Changing the DNS server affected the SuppressQuery status. We need to
+ // deliver RMVs for the previous ADDs (if any) before switching to the new
+ // DNSServer. To keep it simple, we walk all the questions and mark them
+ // to be restarted and then handle all of them at once.
+ q->Restart = 1;
+ q->SuppressQuery = new;
+ for (qptr = q->next ; qptr; qptr = qptr->next)
+ {
+ if (qptr->DuplicateOf == q)
+ qptr->Restart = 1;
+ }
+ Restart = mDNStrue;
+ }
+ else
+ {
+ DNSServerChangeForQuestion(m, q, s);
+ q->unansweredQueries = 0;
+
+ // If we had sent a query out to DNSServer "t" and we are changing to "s", we
+ // need to ignore the responses coming back from "t" as the DNS configuration
+ // has changed e.g., when a new interface is coming up and that becomes the primary
+ // interface, we switch to the DNS servers configured for the primary interface. In
+ // this case, we should not accept responses associated with the previous interface as
+ // the "name" could resolve differently on this new primary interface. Hence, discard
+ // in-flight responses.
+ q->TargetQID = mDNS_NewMessageID(m);
+
+ if (!QuerySuppressed(q))
+ {
+ debugf("uDNS_SetupDNSConfig: Activating query %p %##s (%s)", q, q->qname.c, DNSTypeName(q->qtype));
+ ActivateUnicastQuery(m, q, mDNStrue);
+ // ActivateUnicastQuery is called for duplicate questions also as it does something
+ // special for AutoTunnel questions
+ for (qptr = q->next ; qptr; qptr = qptr->next)
+ {
+ if (qptr->DuplicateOf == q) ActivateUnicastQuery(m, qptr, mDNStrue);
+ }
+ }
+ }
+ }
+ else
+ {
+ debugf("uDNS_SetupDNSConfig: Not Updating DNS server question %p %##s (%s) DNS server %#a:%d %p %d",
+ q, q->qname.c, DNSTypeName(q->qtype), t ? &t->addr : mDNSNULL, mDNSVal16(t ? t->port : zeroIPPort), q->DuplicateOf, q->SuppressUnusable);
+ for (qptr = q->next ; qptr; qptr = qptr->next)
+ if (qptr->DuplicateOf == q) { qptr->validDNSServers = q->validDNSServers; qptr->qDNSServer = q->qDNSServer; }
+ }
+ }
+ }
+ if (Restart)
+ RestartUnicastQuestions(m);
+
+ FORALL_CACHERECORDS(slot, cg, cr)
+ {
+ if (cr->resrec.InterfaceID)
+ continue;
+
+ // We already walked the questions and restarted/reactivated them if the dns server
+ // change affected the question. That should take care of updating the cache. But
+ // what if there is no active question at this point when the DNS server change
+ // happened ? There could be old cache entries lying around and if we don't flush
+ // them, a new question after the DNS server change could pick up these stale
+ // entries and get a wrong answer.
+ //
+ // For cache entries that have active questions we might have skipped rescheduling
+ // the questions if they were suppressed (see above). To keep it simple, we walk
+ // all the cache entries to make sure that there are no stale entries. We use the
+ // active question's InterfaceID/ServiceID for looking up the right DNS server.
+ // Note that the unscoped value for ServiceID is -1.
+ //
+ // Note: If GetServerForName returns NULL, it could either mean that there are no
+ // DNS servers or no matching DNS servers for this question. In either case,
+ // the cache should get purged below when we process deleted DNS servers.
+
+ ptr = GetServerForName(m, cr->resrec.name,
+ (cr->CRActiveQuestion ? cr->CRActiveQuestion->InterfaceID : mDNSNULL),
+ (cr->CRActiveQuestion ? cr->CRActiveQuestion->ServiceID : -1));
+
+ // Purge or Reconfirm if this cache entry would use the new DNS server
+ if (ptr && (ptr != cr->resrec.rDNSServer))
+ {
+ // As the DNSServers for this cache record is not the same anymore, we don't
+ // want any new questions to pick this old value. If there is no active question,
+ // we can't possibly re-confirm, so purge in that case. If it is a DNSSEC question,
+ // purge the cache as the DNSSEC capabilities of the DNS server may have changed.
+
+ if (cr->CRActiveQuestion == mDNSNULL || DNSSECQuestion(cr->CRActiveQuestion))
+ {
+ LogInfo("uDNS_SetupDNSConfig: Purging Resourcerecord %s, New DNS server %#a , Old DNS server %#a", CRDisplayString(m, cr),
+ &ptr->addr, (cr->resrec.rDNSServer != mDNSNULL ? &cr->resrec.rDNSServer->addr : mDNSNULL));
+ mDNS_PurgeCacheResourceRecord(m, cr);
+ }
+ else
+ {
+ LogInfo("uDNS_SetupDNSConfig: Purging/Reconfirming Resourcerecord %s, New DNS server %#a, Old DNS server %#a", CRDisplayString(m, cr),
+ &ptr->addr, (cr->resrec.rDNSServer != mDNSNULL ? &cr->resrec.rDNSServer->addr : mDNSNULL));
+ PurgeOrReconfirmCacheRecord(m, cr, ptr, mDNSfalse);
+ }
+ }
+ }
+
+ while (*p)
+ {
+ if (((*p)->flags & DNSServer_FlagDelete) != 0)
+ {
+ // Scan our cache, looking for uDNS records that we would have queried this server for.
+ // We reconfirm any records that match, because in this world of split DNS, firewalls, etc.
+ // different DNS servers can give different answers to the same question.
+ ptr = *p;
+ FORALL_CACHERECORDS(slot, cg, cr)
+ {
+ if (cr->resrec.InterfaceID) continue;
+ if (cr->resrec.rDNSServer == ptr)
+ {
+ // If we don't have an active question for this cache record, neither Purge can
+ // generate RMV events nor Reconfirm can send queries out. Just set the DNSServer
+ // pointer on the record NULL so that we don't point to freed memory (We might dereference
+ // DNSServer pointers from resource record for logging purposes).
+ //
+ // If there is an active question, point to its DNSServer as long as it does not point to the
+ // freed one. We already went through the questions above and made them point at either the
+ // new server or NULL if there is no server.
+
+ if (cr->CRActiveQuestion)
+ {
+ DNSQuestion *qptr = cr->CRActiveQuestion;
+
+ if (qptr->qDNSServer == ptr)
+ {
+ LogMsg("uDNS_SetupDNSConfig: ERROR!! Cache Record %s Active question %##s (%s) (scope:%p) poining to DNSServer Address %#a"
+ " to be freed", CRDisplayString(m, cr), qptr->qname.c, DNSTypeName(qptr->qtype), qptr->InterfaceID, &ptr->addr);
+ qptr->validDNSServers = zeroOpaque64;
+ qptr->qDNSServer = mDNSNULL;
+ cr->resrec.rDNSServer = mDNSNULL;
+ }
+ else
+ {
+ LogInfo("uDNS_SetupDNSConfig: Cache Record %s, Active question %##s (%s) (scope:%p), pointing to DNSServer %#a (to be deleted),"
+ " resetting to question's DNSServer Address %#a", CRDisplayString(m, cr), qptr->qname.c, DNSTypeName(qptr->qtype),
+ qptr->InterfaceID, &ptr->addr, (qptr->qDNSServer ? &qptr->qDNSServer->addr : mDNSNULL));
+ cr->resrec.rDNSServer = qptr->qDNSServer;
+ }
+ }
+ else
+ {
+ LogInfo("uDNS_SetupDNSConfig: Cache Record %##s has no Active question, Record's DNSServer Address %#a, Server to be deleted %#a",
+ cr->resrec.name, &cr->resrec.rDNSServer->addr, &ptr->addr);
+ cr->resrec.rDNSServer = mDNSNULL;
+ }
+
+ PurgeOrReconfirmCacheRecord(m, cr, ptr, mDNStrue);
+ }
+ }
+ *p = (*p)->next;
+ LogInfo("uDNS_SetupDNSConfig: Deleting server %p %#a:%d (%##s) %d", ptr, &ptr->addr, mDNSVal16(ptr->port), ptr->domain.c, NumUnicastDNSServers);
+ mDNSPlatformMemFree(ptr);
+ }
+ else
+ {
+ (*p)->flags &= ~DNSServer_FlagNew;
+ p = &(*p)->next;
+ }
+ }
+
+ // If we now have no DNS servers at all and we used to have some, then immediately purge all unicast cache records (including for LLQs).
+ // This is important for giving prompt remove events when the user disconnects the Ethernet cable or turns off wireless.
+ // Otherwise, stale data lingers for 5-10 seconds, which is not the user-experience people expect from Bonjour.
+ // Similarly, if we now have some DNS servers and we used to have none, we want to purge any fake negative results we may have generated.
+ if ((m->DNSServers != mDNSNULL) != (oldServers != mDNSNULL))
+ {
+ int count = 0;
+ FORALL_CACHERECORDS(slot, cg, cr)
+ {
+ if (!cr->resrec.InterfaceID)
+ {
+ mDNS_PurgeCacheResourceRecord(m, cr);
+ count++;
+ }
+ }
+ LogInfo("uDNS_SetupDNSConfig: %s available; purged %d unicast DNS records from cache",
+ m->DNSServers ? "DNS server became" : "No DNS servers", count);
+
+ // Force anything that needs to get zone data to get that information again
+ RestartRecordGetZoneData(m);
+ }
+
+ // Did our FQDN change?
+ if (!SameDomainName(&fqdn, &m->FQDN))
+ {
+ if (m->FQDN.c[0]) mDNS_RemoveDynDNSHostName(m, &m->FQDN);
+
+ AssignDomainName(&m->FQDN, &fqdn);
+
+ if (m->FQDN.c[0])
+ {
+ mDNSPlatformDynDNSHostNameStatusChanged(&m->FQDN, 1);
+ mDNS_AddDynDNSHostName(m, &m->FQDN, DynDNSHostNameCallback, mDNSNULL);
+ }
+ }
+
+ mDNS_Unlock(m);
+
+ // handle router and primary interface changes
+ v4 = v6 = r = zeroAddr;
+ v4.type = r.type = mDNSAddrType_IPv4;
- debugf("uDNS_SetupDNSConfig: number of unicast DNS servers %d", NumUnicastDNSServers);
- return mStatus_NoError;
- }
+ if (mDNSPlatformGetPrimaryInterface(m, &v4, &v6, &r) == mStatus_NoError && !mDNSv4AddressIsLinkLocal(&v4.ip.v4))
+ {
+ mDNS_SetPrimaryInterfaceInfo(m,
+ !mDNSIPv4AddressIsZero(v4.ip.v4) ? &v4 : mDNSNULL,
+ !mDNSIPv6AddressIsZero(v6.ip.v6) ? &v6 : mDNSNULL,
+ !mDNSIPv4AddressIsZero(r.ip.v4) ? &r : mDNSNULL);
+ }
+ else
+ {
+ mDNS_SetPrimaryInterfaceInfo(m, mDNSNULL, mDNSNULL, mDNSNULL);
+ if (m->FQDN.c[0]) mDNSPlatformDynDNSHostNameStatusChanged(&m->FQDN, 1); // Set status to 1 to indicate temporary failure
+ }
+
+ debugf("uDNS_SetupDNSConfig: number of unicast DNS servers %d", NumUnicastDNSServers);
+ return mStatus_NoError;
+}
mDNSexport void mDNSCoreInitComplete(mDNS *const m, mStatus result)
- {
- m->mDNSPlatformStatus = result;
- if (m->MainCallback)
- {
- mDNS_Lock(m);
- mDNS_DropLockBeforeCallback(); // Allow client to legally make mDNS API calls from the callback
- m->MainCallback(m, mStatus_NoError);
- mDNS_ReclaimLockAfterCallback(); // Decrement mDNS_reentrancy to block mDNS API calls again
- mDNS_Unlock(m);
- }
- }
+{
+ m->mDNSPlatformStatus = result;
+ if (m->MainCallback)
+ {
+ mDNS_Lock(m);
+ mDNS_DropLockBeforeCallback(); // Allow client to legally make mDNS API calls from the callback
+ m->MainCallback(m, mStatus_NoError);
+ mDNS_ReclaimLockAfterCallback(); // Decrement mDNS_reentrancy to block mDNS API calls again
+ mDNS_Unlock(m);
+ }
+}
mDNSlocal void DeregLoop(mDNS *const m, AuthRecord *const start)
- {
- m->CurrentRecord = start;
- while (m->CurrentRecord)
- {
- AuthRecord *rr = m->CurrentRecord;
- LogInfo("DeregLoop: %s deregistration for %p %02X %s",
- (rr->resrec.RecordType != kDNSRecordTypeDeregistering) ? "Initiating " : "Accelerating",
- rr, rr->resrec.RecordType, ARDisplayString(m, rr));
- if (rr->resrec.RecordType != kDNSRecordTypeDeregistering)
- mDNS_Deregister_internal(m, rr, mDNS_Dereg_rapid);
- else if (rr->AnnounceCount > 1)
- {
- rr->AnnounceCount = 1;
- rr->LastAPTime = m->timenow - rr->ThisAPInterval;
- }
- // Mustn't advance m->CurrentRecord until *after* mDNS_Deregister_internal, because
- // new records could have been added to the end of the list as a result of that call.
- if (m->CurrentRecord == rr) // If m->CurrentRecord was not advanced for us, do it now
- m->CurrentRecord = rr->next;
- }
- }
+{
+ m->CurrentRecord = start;
+ while (m->CurrentRecord)
+ {
+ AuthRecord *rr = m->CurrentRecord;
+ LogInfo("DeregLoop: %s deregistration for %p %02X %s",
+ (rr->resrec.RecordType != kDNSRecordTypeDeregistering) ? "Initiating " : "Accelerating",
+ rr, rr->resrec.RecordType, ARDisplayString(m, rr));
+ if (rr->resrec.RecordType != kDNSRecordTypeDeregistering)
+ mDNS_Deregister_internal(m, rr, mDNS_Dereg_rapid);
+ else if (rr->AnnounceCount > 1)
+ {
+ rr->AnnounceCount = 1;
+ rr->LastAPTime = m->timenow - rr->ThisAPInterval;
+ }
+ // Mustn't advance m->CurrentRecord until *after* mDNS_Deregister_internal, because
+ // new records could have been added to the end of the list as a result of that call.
+ if (m->CurrentRecord == rr) // If m->CurrentRecord was not advanced for us, do it now
+ m->CurrentRecord = rr->next;
+ }
+}
mDNSexport void mDNS_StartExit(mDNS *const m)
- {
- NetworkInterfaceInfo *intf;
- AuthRecord *rr;
+{
+ NetworkInterfaceInfo *intf;
+ AuthRecord *rr;
- mDNS_Lock(m);
+ mDNS_Lock(m);
- LogInfo("mDNS_StartExit");
- m->ShutdownTime = NonZeroTime(m->timenow + mDNSPlatformOneSecond * 5);
+ LogInfo("mDNS_StartExit");
+ m->ShutdownTime = NonZeroTime(m->timenow + mDNSPlatformOneSecond * 5);
- mDNSCoreBeSleepProxyServer_internal(m, 0, 0, 0, 0);
+ mDNSCoreBeSleepProxyServer_internal(m, 0, 0, 0, 0, 0);
#if APPLE_OSX_mDNSResponder
-#if ! NO_WCF
- CHECK_WCF_FUNCTION(WCFConnectionDealloc)
- {
- if (m->WCF) WCFConnectionDealloc((WCFConnection *)m->WCF);
- }
+#if !NO_WCF
+ CHECK_WCF_FUNCTION(WCFConnectionDealloc)
+ {
+ if (m->WCF) WCFConnectionDealloc((WCFConnection *)m->WCF);
+ }
#endif
#endif
#ifndef UNICAST_DISABLED
- {
- SearchListElem *s;
- SuspendLLQs(m);
- // Don't need to do SleepRecordRegistrations() here
- // because we deregister all records and services later in this routine
- while (m->Hostnames) mDNS_RemoveDynDNSHostName(m, &m->Hostnames->fqdn);
-
- // For each member of our SearchList, deregister any records it may have created, and cut them from the list.
- // Otherwise they'll be forcibly deregistered for us (without being cut them from the appropriate list)
- // and we may crash because the list still contains dangling pointers.
- for (s = SearchList; s; s = s->next)
- while (s->AuthRecs)
- {
- ARListElem *dereg = s->AuthRecs;
- s->AuthRecs = s->AuthRecs->next;
- mDNS_Deregister_internal(m, &dereg->ar, mDNS_Dereg_normal); // Memory will be freed in the FreeARElemCallback
- }
- }
+ {
+ SearchListElem *s;
+ SuspendLLQs(m);
+ // Don't need to do SleepRecordRegistrations() here
+ // because we deregister all records and services later in this routine
+ while (m->Hostnames) mDNS_RemoveDynDNSHostName(m, &m->Hostnames->fqdn);
+
+ // For each member of our SearchList, deregister any records it may have created, and cut them from the list.
+ // Otherwise they'll be forcibly deregistered for us (without being cut them from the appropriate list)
+ // and we may crash because the list still contains dangling pointers.
+ for (s = SearchList; s; s = s->next)
+ while (s->AuthRecs)
+ {
+ ARListElem *dereg = s->AuthRecs;
+ s->AuthRecs = s->AuthRecs->next;
+ mDNS_Deregister_internal(m, &dereg->ar, mDNS_Dereg_normal); // Memory will be freed in the FreeARElemCallback
+ }
+ }
#endif
- for (intf = m->HostInterfaces; intf; intf = intf->next)
- if (intf->Advertise)
- DeadvertiseInterface(m, intf);
-
- // Shut down all our active NAT Traversals
- while (m->NATTraversals)
- {
- NATTraversalInfo *t = m->NATTraversals;
- mDNS_StopNATOperation_internal(m, t); // This will cut 't' from the list, thereby advancing m->NATTraversals in the process
-
- // After stopping the NAT Traversal, we zero out the fields.
- // This has particularly important implications for our AutoTunnel records --
- // when we deregister our AutoTunnel records below, we don't want their mStatus_MemFree
- // handlers to just turn around and attempt to re-register those same records.
- // Clearing t->ExternalPort/t->RequestedPort will cause the mStatus_MemFree callback handlers
- // to not do this.
- t->ExternalAddress = zerov4Addr;
- t->ExternalPort = zeroIPPort;
- t->RequestedPort = zeroIPPort;
- t->Lifetime = 0;
- t->Result = mStatus_NoError;
- }
-
- // Make sure there are nothing but deregistering records remaining in the list
- if (m->CurrentRecord)
- LogMsg("mDNS_StartExit: ERROR m->CurrentRecord already set %s", ARDisplayString(m, m->CurrentRecord));
-
- // We're in the process of shutting down, so queries, etc. are no longer available.
- // Consequently, determining certain information, e.g. the uDNS update server's IP
- // address, will not be possible. The records on the main list are more likely to
- // already contain such information, so we deregister the duplicate records first.
- LogInfo("mDNS_StartExit: Deregistering duplicate resource records");
- DeregLoop(m, m->DuplicateRecords);
- LogInfo("mDNS_StartExit: Deregistering resource records");
- DeregLoop(m, m->ResourceRecords);
-
- // If we scheduled a response to send goodbye packets, we set NextScheduledResponse to now. Normally when deregistering records,
- // we allow up to 100ms delay (to help improve record grouping) but when shutting down we don't want any such delay.
- if (m->NextScheduledResponse - m->timenow < mDNSPlatformOneSecond)
- {
- m->NextScheduledResponse = m->timenow;
- m->SuppressSending = 0;
- }
+ for (intf = m->HostInterfaces; intf; intf = intf->next)
+ if (intf->Advertise)
+ DeadvertiseInterface(m, intf);
- if (m->ResourceRecords) LogInfo("mDNS_StartExit: Sending final record deregistrations");
- else LogInfo("mDNS_StartExit: No deregistering records remain");
+ // Shut down all our active NAT Traversals
+ while (m->NATTraversals)
+ {
+ NATTraversalInfo *t = m->NATTraversals;
+ mDNS_StopNATOperation_internal(m, t); // This will cut 't' from the list, thereby advancing m->NATTraversals in the process
+
+ // After stopping the NAT Traversal, we zero out the fields.
+ // This has particularly important implications for our AutoTunnel records --
+ // when we deregister our AutoTunnel records below, we don't want their mStatus_MemFree
+ // handlers to just turn around and attempt to re-register those same records.
+ // Clearing t->ExternalPort/t->RequestedPort will cause the mStatus_MemFree callback handlers
+ // to not do this.
+ t->ExternalAddress = zerov4Addr;
+ t->NewAddress = zerov4Addr;
+ t->ExternalPort = zeroIPPort;
+ t->RequestedPort = zeroIPPort;
+ t->Lifetime = 0;
+ t->Result = mStatus_NoError;
+ }
+
+ // Make sure there are nothing but deregistering records remaining in the list
+ if (m->CurrentRecord)
+ LogMsg("mDNS_StartExit: ERROR m->CurrentRecord already set %s", ARDisplayString(m, m->CurrentRecord));
+
+ // We're in the process of shutting down, so queries, etc. are no longer available.
+ // Consequently, determining certain information, e.g. the uDNS update server's IP
+ // address, will not be possible. The records on the main list are more likely to
+ // already contain such information, so we deregister the duplicate records first.
+ LogInfo("mDNS_StartExit: Deregistering duplicate resource records");
+ DeregLoop(m, m->DuplicateRecords);
+ LogInfo("mDNS_StartExit: Deregistering resource records");
+ DeregLoop(m, m->ResourceRecords);
+
+ // If we scheduled a response to send goodbye packets, we set NextScheduledResponse to now. Normally when deregistering records,
+ // we allow up to 100ms delay (to help improve record grouping) but when shutting down we don't want any such delay.
+ if (m->NextScheduledResponse - m->timenow < mDNSPlatformOneSecond)
+ {
+ m->NextScheduledResponse = m->timenow;
+ m->SuppressSending = 0;
+ }
- for (rr = m->DuplicateRecords; rr; rr = rr->next)
- LogMsg("mDNS_StartExit: Should not still have Duplicate Records remaining: %02X %s", rr->resrec.RecordType, ARDisplayString(m, rr));
+ if (m->ResourceRecords) LogInfo("mDNS_StartExit: Sending final record deregistrations");
+ else LogInfo("mDNS_StartExit: No deregistering records remain");
- // If any deregistering records remain, send their deregistration announcements before we exit
- if (m->mDNSPlatformStatus != mStatus_NoError) DiscardDeregistrations(m);
+ for (rr = m->DuplicateRecords; rr; rr = rr->next)
+ LogMsg("mDNS_StartExit: Should not still have Duplicate Records remaining: %02X %s", rr->resrec.RecordType, ARDisplayString(m, rr));
- mDNS_Unlock(m);
+ // If any deregistering records remain, send their deregistration announcements before we exit
+ if (m->mDNSPlatformStatus != mStatus_NoError) DiscardDeregistrations(m);
- LogInfo("mDNS_StartExit: done");
- }
+ mDNS_Unlock(m);
+
+ LogInfo("mDNS_StartExit: done");
+}
mDNSexport void mDNS_FinalExit(mDNS *const m)
- {
- mDNSu32 rrcache_active = 0;
- mDNSu32 rrcache_totalused = 0;
- mDNSu32 slot;
- AuthRecord *rr;
-
- LogInfo("mDNS_FinalExit: mDNSPlatformClose");
- mDNSPlatformClose(m);
-
- rrcache_totalused = m->rrcache_totalused;
- for (slot = 0; slot < CACHE_HASH_SLOTS; slot++)
- {
- while (m->rrcache_hash[slot])
- {
- CacheGroup *cg = m->rrcache_hash[slot];
- while (cg->members)
- {
- CacheRecord *cr = cg->members;
- cg->members = cg->members->next;
- if (cr->CRActiveQuestion) rrcache_active++;
- ReleaseCacheRecord(m, cr);
- }
- cg->rrcache_tail = &cg->members;
- ReleaseCacheGroup(m, &m->rrcache_hash[slot]);
- }
- }
- debugf("mDNS_FinalExit: RR Cache was using %ld records, %lu active", rrcache_totalused, rrcache_active);
- if (rrcache_active != m->rrcache_active)
- LogMsg("*** ERROR *** rrcache_active %lu != m->rrcache_active %lu", rrcache_active, m->rrcache_active);
-
- for (rr = m->ResourceRecords; rr; rr = rr->next)
- LogMsg("mDNS_FinalExit failed to send goodbye for: %p %02X %s", rr, rr->resrec.RecordType, ARDisplayString(m, rr));
-
- LogInfo("mDNS_FinalExit: done");
- }
+{
+ mDNSu32 rrcache_active = 0;
+ mDNSu32 rrcache_totalused = 0;
+ mDNSu32 slot;
+ AuthRecord *rr;
+
+ LogInfo("mDNS_FinalExit: mDNSPlatformClose");
+ mDNSPlatformClose(m);
+
+ rrcache_totalused = m->rrcache_totalused;
+ for (slot = 0; slot < CACHE_HASH_SLOTS; slot++)
+ {
+ while (m->rrcache_hash[slot])
+ {
+ CacheGroup *cg = m->rrcache_hash[slot];
+ while (cg->members)
+ {
+ CacheRecord *cr = cg->members;
+ cg->members = cg->members->next;
+ if (cr->CRActiveQuestion) rrcache_active++;
+ ReleaseCacheRecord(m, cr);
+ }
+ cg->rrcache_tail = &cg->members;
+ ReleaseCacheGroup(m, &m->rrcache_hash[slot]);
+ }
+ }
+ debugf("mDNS_FinalExit: RR Cache was using %ld records, %lu active", rrcache_totalused, rrcache_active);
+ if (rrcache_active != m->rrcache_active)
+ LogMsg("*** ERROR *** rrcache_active %lu != m->rrcache_active %lu", rrcache_active, m->rrcache_active);
+
+ for (rr = m->ResourceRecords; rr; rr = rr->next)
+ LogMsg("mDNS_FinalExit failed to send goodbye for: %p %02X %s", rr, rr->resrec.RecordType, ARDisplayString(m, rr));
+
+ LogInfo("mDNS_FinalExit: done");
+}
projects / apple / mdnsresponder.git / blobdiff