mDNSResponder-258.13.tar.gz

[apple/mdnsresponder.git] / mDNSMacOSX / mDNSMacOSX.c

/* -*- Mode: C; tab-width: 4 -*-
 *
 * Copyright (c) 2002-2004 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.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

// ***************************************************************************
// mDNSMacOSX.c:
// Supporting routines to run mDNS on a CFRunLoop platform
// ***************************************************************************

// For debugging, set LIST_ALL_INTERFACES to 1 to display all found interfaces,
// including ones that mDNSResponder chooses not to use.
#define LIST_ALL_INTERFACES 0

// For enabling AAAA records over IPv4. Setting this to 0 sends only
// A records over IPv4 and AAAA over IPv6. Setting this to 1 sends both
// AAAA and A records over both IPv4 and IPv6.
#define AAAA_OVER_V4 1

// In Mac OS X 10.4 and earlier, to reduce traffic, we would send and receive using IPv6 only on interfaces that had no routable
// IPv4 address. Having a routable IPv4 address assigned is a reasonable indicator of being on a large configured network,
// which means there's a good chance that most or all the other devices on that network should also have IPv4.
// By doing this we lost the ability to talk to true IPv6-only devices on that link, but we cut the packet rate in half.
// At that time, reducing the packet rate was more important than v6-only devices on a large configured network,
// so were willing to make that sacrifice.
// In Mac OS X 10.5, in 2007, two things have changed:
// 1. IPv6-only devices are starting to become more common, so we can't ignore them.
// 2. Other efficiency improvements in the code mean that crude hacks like this should no longer be necessary.

#define USE_V6_ONLY_WHEN_NO_ROUTABLE_V4 0

#include "mDNSEmbeddedAPI.h"            // Defines the interface provided to the client layer above
#include "DNSCommon.h"
#include "uDNS.h"
#include "mDNSMacOSX.h"                         // Defines the specific types needed to run mDNS on this platform
#include "dns_sd.h"                                     // For mDNSInterface_LocalOnly etc.
#include "PlatformCommon.h"
#include "uds_daemon.h"
#include <CoreServices/CoreServices.h>

#include <stdio.h>
#include <stdarg.h>                 // For va_list support
#include <stdlib.h>                 // For arc4random
#include <net/if.h>
#include <net/if_types.h>                       // For IFT_ETHER
#include <net/if_dl.h>
#include <net/bpf.h>                            // For BIOCSETIF etc.
#include <sys/uio.h>
#include <sys/param.h>
#include <sys/socket.h>
#include <sys/sysctl.h>
#include <sys/event.h>
#include <fcntl.h>
#include <sys/ioctl.h>
#include <time.h>                   // platform support for UTC time
#include <arpa/inet.h>              // for inet_aton
#include <pthread.h>

#include <netinet/in.h>             // For IP_RECVTTL
#ifndef IP_RECVTTL
#define IP_RECVTTL 24               // bool; receive reception TTL w/dgram
#endif

#include <netinet/in_systm.h>       // For n_long, required by <netinet/ip.h> below
#include <netinet/ip.h>             // For IPTOS_LOWDELAY etc.
#include <netinet6/in6_var.h>       // For IN6_IFF_NOTREADY etc.
#include <netinet6/nd6.h>           // For ND6_INFINITE_LIFETIME etc.

#if TARGET_OS_EMBEDDED
#define NO_SECURITYFRAMEWORK 1
#define NO_CFUSERNOTIFICATION 1
#endif

#ifndef NO_SECURITYFRAMEWORK
#include <Security/SecureTransport.h>
#include <Security/Security.h>
#endif /* NO_SECURITYFRAMEWORK */

#include <DebugServices.h>
#include "dnsinfo.h"

// Code contributed by Dave Heller:
// Define RUN_ON_PUMA_WITHOUT_IFADDRS to compile code that will
// work on Mac OS X 10.1, which does not have the getifaddrs call.
#define RUN_ON_PUMA_WITHOUT_IFADDRS 0
#if RUN_ON_PUMA_WITHOUT_IFADDRS
#include "mDNSMacOSXPuma.c"
#else
#include <ifaddrs.h>
#endif

#include <IOKit/IOKitLib.h>
#include <IOKit/IOMessage.h>

#ifdef __LIB_DISPATCH__
// This is currently defined in IOKit/PrivateHeaders/IOKitLibPrivate.h. Till it becomes an Public
// API, we will have our own declaration
void IONotificationPortSetDispatchQueue(IONotificationPortRef notify, dispatch_queue_t queue);
#endif

#if USE_IOPMCOPYACTIVEPMPREFERENCES
#include <IOKit/ps/IOPowerSources.h>
#include <IOKit/ps/IOPowerSourcesPrivate.h>
#endif

#include <mach/mach_error.h>
#include <mach/mach_port.h>
#include <mach/mach_time.h>
#include "helper.h"

#include <asl.h>

#if APPLE_OSX_mDNSResponder
#include <DeviceToDeviceManager/DeviceToDeviceManager.h>
#include <AWACS.h>

#if ! NO_D2D
D2DStatus D2DInitialize(CFRunLoopRef runLoop, D2DServiceCallback serviceCallback, void* userData) __attribute__((weak_import));
D2DStatus D2DTerminate() __attribute__((weak_import));
D2DStatus D2DStartAdvertisingPair(const Byte *key, const size_t keySize, const Byte *value, const size_t valueSize) __attribute__((weak_import));
D2DStatus D2DStopAdvertisingPair(const Byte *key, const size_t keySize, const Byte *value, const size_t valueSize) __attribute__((weak_import));
D2DStatus D2DStartBrowsingForKey(const Byte *key, const size_t keySize) __attribute__((weak_import));
D2DStatus D2DStopBrowsingForKey(const Byte *key, const size_t keySize) __attribute__((weak_import));
void D2DStartResolvingPair(const Byte *key, const size_t keySize, const Byte *value, const size_t valueSize) __attribute__((weak_import));
void D2DStopResolvingPair(const Byte *key, const size_t keySize, const Byte *value, const size_t valueSize) __attribute__((weak_import));
D2DStatus D2DRetain(D2DServiceInstance instanceHandle, D2DTransportType transportType) __attribute__((weak_import));
D2DStatus D2DRelease(D2DServiceInstance instanceHandle, D2DTransportType transportType) __attribute__((weak_import));

#define CHECK_D2D_FUNCTION(X) if (X)

#endif // ! NO_D2D

#else
#define NO_D2D 1
#define NO_AWACS 1
#endif // APPLE_OSX_mDNSResponder

#define kInterfaceSpecificOption "interface="

// ***************************************************************************
// Globals

#if COMPILER_LIKES_PRAGMA_MARK
#pragma mark - Globals
#endif

// By default we don't offer sleep proxy service
// If OfferSleepProxyService is set non-zero (typically via command-line switch),
// then we'll offer sleep proxy service on desktop Macs that are set to never sleep.
// We currently do not offer sleep proxy service on laptops, or on machines that are set to go to sleep.
mDNSexport int OfferSleepProxyService = 0;
mDNSexport int DisableSleepProxyClient = 0;

// We disable inbound relay connection if this value is set to true (typically via command-line switch).
mDNSBool DisableInboundRelayConnection = mDNSfalse;
mDNSexport int OSXVers;
mDNSexport int KQueueFD;

#ifndef NO_SECURITYFRAMEWORK
static CFArrayRef ServerCerts;
OSStatus SSLSetAllowAnonymousCiphers(SSLContextRef context, Boolean enable);
#endif /* NO_SECURITYFRAMEWORK */

static CFStringRef NetworkChangedKey_IPv4;
static CFStringRef NetworkChangedKey_IPv6;
static CFStringRef NetworkChangedKey_Hostnames;
static CFStringRef NetworkChangedKey_Computername;
static CFStringRef NetworkChangedKey_DNS;
static CFStringRef NetworkChangedKey_DynamicDNS       = CFSTR("Setup:/Network/DynamicDNS");
static CFStringRef NetworkChangedKey_BackToMyMac      = CFSTR("Setup:/Network/BackToMyMac");
static CFStringRef NetworkChangedKey_BTMMConnectivity = CFSTR("State:/Network/Connectivity");
static CFStringRef NetworkChangedKey_PowerSettings    = CFSTR("State:/IOKit/PowerManagement/CurrentSettings");

static char  HINFO_HWstring_buffer[32];
static char *HINFO_HWstring = "Device";
static int   HINFO_HWstring_prefixlen = 6;

mDNSexport int WatchDogReportingThreshold = 250;

#ifdef __LIB_DISPATCH__
dispatch_queue_t SSLqueue;
#endif

#if APPLE_OSX_mDNSResponder
static mDNSu8 SPMetricPortability   = 99;
static mDNSu8 SPMetricMarginalPower = 99;
static mDNSu8 SPMetricTotalPower    = 99;
mDNSexport domainname ActiveDirectoryPrimaryDomain;
mDNSexport int        ActiveDirectoryPrimaryDomainLabelCount;
mDNSexport mDNSAddr   ActiveDirectoryPrimaryDomainServer;
#endif // APPLE_OSX_mDNSResponder

// ***************************************************************************
#if COMPILER_LIKES_PRAGMA_MARK
#pragma mark -
#pragma mark - D2D Support
#endif

#if ! NO_D2D

// Name compression items for fake packet version number 1
static const mDNSu8 compression_packet_v1 = 0x01;

static DNSMessage compression_base_msg = { { {{0}}, {{0}}, 2, 0, 0, 0 }, "\x04_tcp\x05local\x00\x00\x0C\x00\x01\x04_udp\xC0\x11\x00\x0C\x00\x01" };
static mDNSu8 *const compression_limit = (mDNSu8 *) &compression_base_msg + sizeof(DNSMessage);
static mDNSu8 *const compression_lhs = (mDNSu8 *const) compression_base_msg.data + 27;

mDNSlocal void FreeD2DARElemCallback(mDNS *const m, AuthRecord *const rr, mStatus result);
mDNSlocal void PrintHex(mDNSu8 *data, mDNSu16 len);

static ARListElem *D2DRecords = NULL; // List of locally-generated PTR records to records found via D2D

typedef struct D2DBrowseListElem
        {
        struct D2DBrowseListElem *next;
        domainname name;
        mDNSu16 type;
        unsigned int refCount;
        } D2DBrowseListElem;

D2DBrowseListElem* D2DBrowseList = NULL;

mDNSlocal mDNSu8 *putVal16(mDNSu8 *ptr, mDNSu16 val)
        {
        ptr[0] = (mDNSu8)((val >> 8 ) & 0xFF);
        ptr[1] = (mDNSu8)((val      ) & 0xFF);
        return ptr + sizeof(mDNSu16);
        }

mDNSlocal mDNSu8 *putVal32(mDNSu8 *ptr, mDNSu32 val)
        {
        ptr[0] = (mDNSu8)((val >> 24) & 0xFF);
        ptr[1] = (mDNSu8)((val >> 16) & 0xFF);
        ptr[2] = (mDNSu8)((val >>  8) & 0xFF);
        ptr[3] = (mDNSu8)((val      ) & 0xFF);
        return ptr + sizeof(mDNSu32);
        }

mDNSlocal void DomainnameToLower(const domainname * const in, domainname * const out)
        {
        const mDNSu8 * const start = (const mDNSu8 * const)in;
        mDNSu8 *ptr = (mDNSu8*)start;
        while(*ptr)
                {
                mDNSu8 c = *ptr;
                out->c[ptr-start] = *ptr;
                ptr++;
                for (;c;c--,ptr++) out->c[ptr-start] = mDNSIsUpperCase(*ptr) ? (*ptr - 'A' + 'a') : *ptr;
                }
        out->c[ptr-start] = *ptr;
        }

mDNSlocal mStatus DNSNameCompressionParseBytes(mDNS *const m, const mDNSu8 *const lhs, const mDNSu16 lhs_len, const mDNSu8 *const rhs, const mDNSu16 rhs_len, AuthRecord *rr)
        {
        if (mDNS_LoggingEnabled)
                {
                LogInfo("%s", __func__);
                LogInfo("  Static Bytes: ");
                PrintHex((mDNSu8*)&compression_base_msg, compression_lhs - (mDNSu8*)&compression_base_msg);
                }
        
        mDNSu8 *ptr = compression_lhs; // pointer to the end of our fake packet

        // Check to make sure we're not going to go past the end of the DNSMessage data
        // 7 = 2 for CLASS (-1 for our version) + 4 for TTL + 2 for RDLENGTH
        if (ptr + lhs_len - 7 + rhs_len >= compression_limit) return mStatus_NoMemoryErr;
        
        // Copy the LHS onto our fake wire packet
        mDNSPlatformMemCopy(ptr, lhs, lhs_len);
        ptr += lhs_len - 1;
        
        // Check the 'fake packet' version number, to ensure that we know how to decompress this data
        if (*ptr != compression_packet_v1) return mStatus_Incompatible;
        
        // two bytes of CLASS
        ptr = putVal16(ptr, kDNSClass_IN | kDNSClass_UniqueRRSet);
        
        // four bytes of TTL
        ptr = putVal32(ptr, 120);
        
        // Copy the RHS length into the RDLENGTH of our fake wire packet
        ptr = putVal16(ptr, rhs_len);
        
        // Copy the RHS onto our fake wire packet
        mDNSPlatformMemCopy(ptr, rhs, rhs_len);
        ptr += rhs_len;
        
        if (mDNS_LoggingEnabled)
                {
                LogInfo("  Our Bytes %d: ", __LINE__);
                PrintHex(compression_lhs, ptr - compression_lhs);
                }

        ptr = (mDNSu8 *) GetLargeResourceRecord(m, &compression_base_msg, compression_lhs, ptr, mDNSInterface_Any, kDNSRecordTypePacketAns, &m->rec);
        if (!ptr || m->rec.r.resrec.RecordType == kDNSRecordTypePacketNegative)
                { LogMsg("DNSNameCompressionParseBytes: failed to get large RR"); m->rec.r.resrec.RecordType = 0; return mStatus_UnknownErr; }
        else LogInfo("DNSNameCompressionParseBytes: got rr: %s", CRDisplayString(m, &m->rec.r));        

        mDNS_SetupResourceRecord(rr, mDNSNULL, mDNSInterface_P2P, m->rec.r.resrec.rrtype, 7200, kDNSRecordTypeShared, FreeD2DARElemCallback, NULL);
        AssignDomainName(&rr->namestorage, &m->rec.namestorage);
        rr->resrec.rdlength = m->rec.r.resrec.rdlength;
        rr->resrec.rdata->MaxRDLength = m->rec.r.resrec.rdlength;
        mDNSPlatformMemCopy(rr->resrec.rdata->u.data, m->rec.r.resrec.rdata->u.data, m->rec.r.resrec.rdlength);
        rr->resrec.namehash = DomainNameHashValue(rr->resrec.name);
        SetNewRData(&rr->resrec, mDNSNULL, 0);  // Sets rr->rdatahash for us
        
        m->rec.r.resrec.RecordType = 0; // Mark m->rec as no longer in use

        return mStatus_NoError;
        }

mDNSlocal mDNSu8 * DNSNameCompressionBuildLHS(const domainname const *typeDomain, DNS_TypeValues qtype)
        {
        mDNSu8 *ptr = putDomainNameAsLabels(&compression_base_msg, compression_lhs, compression_limit, typeDomain);
        if (!ptr) return ptr;
        *ptr = (qtype >> 8) & 0xff;
        ptr += 1;
        *ptr = qtype & 0xff;
        ptr += 1;
        *ptr = compression_packet_v1;
        return ptr + 1;
        }

mDNSlocal mDNSu8 * DNSNameCompressionBuildRHS(mDNSu8 *start, const ResourceRecord *const resourceRecord)
        {
        return putRData(&compression_base_msg, start, compression_limit, resourceRecord);
        }

mDNSlocal void PrintHex(mDNSu8 *data, mDNSu16 len)
        {
        mDNSu8 *end = data + len;
        char buffer[49] = {0};
        char *bufend = buffer + sizeof(buffer);
        while(data<end)
                {
                char *ptr = buffer;
                for(; data < end && ptr < bufend-1; ptr+=3,data++)
                        mDNS_snprintf(ptr, bufend - ptr, "%02X ", *data);
                LogInfo("    %s", buffer);
                }
        }

mDNSlocal void PrintHelper(const char *const tag, mDNSu8 *lhs, mDNSu16 lhs_len, mDNSu8 *rhs, mDNSu16 rhs_len)
        {
        if (!mDNS_LoggingEnabled) return;
        
        LogInfo("%s:", tag);
        LogInfo("  LHS: ");
        PrintHex(lhs, lhs_len);
        
        if (!rhs) return;
        
        LogInfo("  RHS: ");
        PrintHex(rhs, rhs_len);
        }

mDNSlocal void FreeD2DARElemCallback(mDNS *const m, AuthRecord *const rr, mStatus result)
        {
        (void)m;  // unused
        if (result == mStatus_MemFree)
                {
                ARListElem **ptr = &D2DRecords;
                ARListElem *tmp;
                while (*ptr && &(*ptr)->ar != rr) ptr = &(*ptr)->next;
                if (!*ptr) { LogMsg("FreeD2DARElemCallback: Could not find in D2DRecords: %s", ARDisplayString(m, rr)); return; }
                LogInfo("FreeD2DARElemCallback: Found in D2DRecords: %s", ARDisplayString(m, rr));
                tmp = *ptr;
                *ptr = (*ptr)->next;
                // Just because we stoppped browsing, doesn't mean we should tear down the PAN connection.
                mDNSPlatformMemFree(tmp);
                }
        }

mDNSlocal void xD2DClearCache(mDNS *const m, const domainname *regType)
        {
        ARListElem *ptr = D2DRecords;
        for ( ; ptr ; ptr = ptr->next)
                {
                if (SameDomainName(&ptr->ar.namestorage, regType)) 
                        {
                        char buffer[MAX_ESCAPED_DOMAIN_NAME];
                        mDNS_Deregister(m, &ptr->ar);
                        ConvertDomainNameToCString(regType, buffer);
                        LogInfo("xD2DClearCache: Clearing cache record and deregistering %s", buffer);  
                        }
                }
        }

mDNSlocal D2DBrowseListElem ** D2DFindInBrowseList(const domainname *const name, mDNSu16 type)
        {
        D2DBrowseListElem **ptr = &D2DBrowseList;

        for ( ; *ptr; ptr = &(*ptr)->next)
                if ((*ptr)->type == type && SameDomainName(&(*ptr)->name, name))
                        break;
        
        return ptr;
        }

mDNSlocal unsigned int D2DBrowseListRefCount(const domainname *const name, mDNSu16 type)
        {
        D2DBrowseListElem **ptr = D2DFindInBrowseList(name, type);
        return *ptr ? (*ptr)->refCount : 0;
        }

mDNSlocal void D2DBrowseListRetain(const domainname *const name, mDNSu16 type)
        {
        D2DBrowseListElem **ptr = D2DFindInBrowseList(name, type);
        
        if (!*ptr)
        {
                *ptr = mDNSPlatformMemAllocate(sizeof(**ptr));
                mDNSPlatformMemZero(*ptr, sizeof(**ptr));
                (*ptr)->type = type;
                AssignDomainName(&(*ptr)->name, name);
        }
        (*ptr)->refCount += 1;
        
        LogInfo("D2DBrowseListRetain: %##s %s refcount now %u", (*ptr)->name.c, DNSTypeName((*ptr)->type), (*ptr)->refCount);   
        }

mDNSlocal void D2DBrowseListRelease(const domainname *const name, mDNSu16 type)
        {       
        D2DBrowseListElem **ptr = D2DFindInBrowseList(name, type);
        
        if (!*ptr) { LogMsg("D2DBrowseListRelease: Didn't find %##s %s in list", name->c, DNSTypeName(type)); return; }
        
        (*ptr)->refCount -= 1;
        
        LogInfo("D2DBrowseListRelease: %##s %s refcount now %u", (*ptr)->name.c, DNSTypeName((*ptr)->type), (*ptr)->refCount);
        
        if (!(*ptr)->refCount)
        {
                D2DBrowseListElem *tmp = *ptr;
                *ptr = (*ptr)->next;
                mDNSPlatformMemFree(tmp);
        }
        }

mDNSlocal mStatus xD2DParse(mDNS *const m, const mDNSu8 * const lhs, const mDNSu16 lhs_len, const mDNSu8 * const rhs, const mDNSu16 rhs_len, AuthRecord *rr)
        {
        if (*(lhs + (lhs_len - 1)) == compression_packet_v1)
                return DNSNameCompressionParseBytes(m, lhs, lhs_len, rhs, rhs_len, rr);
        else
                return mStatus_Incompatible;
        }

mDNSlocal void xD2DAddToCache(mDNS *const m, D2DStatus result, D2DServiceInstance instanceHandle, D2DTransportType transportType, const Byte *key, size_t keySize, const Byte *value, size_t valueSize)
        {
        (void)transportType; // We don't care about this, yet.
        (void)instanceHandle; // We don't care about this, yet.
        
        if (result == kD2DSuccess)
                {
                if ( key == NULL || value == NULL || keySize == 0 || valueSize == 0) { LogMsg("xD2DAddToCache: NULL Byte * passed in or length == 0"); return; }
                
                mStatus err;
                ARListElem *ptr = mDNSPlatformMemAllocate(sizeof(ARListElem) + (valueSize < sizeof(RData) ? 0 : valueSize - sizeof(RData)));

                if (ptr == NULL) { LogMsg("xD2DAddToCache: memory allocation failure"); return; }

                err = xD2DParse(m, (const mDNSu8 * const)key, (const mDNSu16)keySize, (const mDNSu8 * const)value, (const mDNSu16)valueSize, &ptr->ar);
                if (err)
                        {
                        LogMsg("xD2DAddToCache: xD2DParse returned error: %d", err);
                        PrintHelper(__func__, (mDNSu8 *)key, (mDNSu16)keySize, (mDNSu8 *)value, (mDNSu16)valueSize);
                        mDNSPlatformMemFree(ptr);
                        return;
                        }
                        
                err = mDNS_Register(m, &ptr->ar);
                if (err)
                        {
                        LogMsg("xD2DAddToCache: mDNS_Register returned error %d for %s", err, ARDisplayString(m, &ptr->ar));
                        mDNSPlatformMemFree(ptr);
                        return;
                        }

                LogInfo("xD2DAddToCache: mDNS_Register succeeded for %s", ARDisplayString(m, &ptr->ar));
                ptr->next = D2DRecords;
                D2DRecords = ptr;
                }
        else
                LogMsg("xD2DAddToCache: Unexpected result %d", result);
        }

mDNSlocal ARListElem * xD2DFindInList(mDNS *const m, const Byte *const key, const size_t keySize, const Byte *const value, const size_t valueSize)
        {
        ARListElem *ptr = D2DRecords;
        ARListElem *arptr;
        
        if ( key == NULL || value == NULL || keySize == 0 || valueSize == 0) { LogMsg("xD2DFindInList: NULL Byte * passed in or length == 0"); return NULL; }

        arptr = mDNSPlatformMemAllocate(sizeof(ARListElem) + (valueSize < sizeof(RData) ? 0 : valueSize - sizeof(RData)));
        if (arptr == NULL) { LogMsg("xD2DFindInList: memory allocation failure"); return NULL; }

        if (xD2DParse(m, (const mDNSu8 *const)key, (const mDNSu16)keySize, (const mDNSu8 *const)value, (const mDNSu16)valueSize, &arptr->ar) != mStatus_NoError)
                {
                LogMsg("xD2DFindInList: xD2DParse failed for key: %p (%u) value: %p (%u)", key, keySize, value, valueSize);
                mDNSPlatformMemFree(arptr);
                return NULL;
                }
                
        while (ptr)
                {
                if (IdenticalResourceRecord(&arptr->ar.resrec, &ptr->ar.resrec)) break;
                ptr = ptr->next;
                }
                
        if (!ptr) LogMsg("xD2DFindInList: Could not find in D2DRecords: %s", ARDisplayString(m, &arptr->ar));
        mDNSPlatformMemFree(arptr);
        return ptr;
        }

mDNSlocal void xD2DRemoveFromCache(mDNS *const m, D2DStatus result, D2DServiceInstance instanceHandle, D2DTransportType transportType, const Byte *key, size_t keySize, const Byte *value, size_t valueSize)
        {
        (void)transportType; // We don't care about this, yet.
        (void)instanceHandle; // We don't care about this, yet.
        
        if (result == kD2DSuccess)
                {
                ARListElem *ptr = xD2DFindInList(m, key, keySize, value, valueSize);
                if (ptr) 
                        {
                        LogInfo("xD2DRemoveFromCache: Remove from cache: %s", ARDisplayString(m, &ptr->ar));
                        mDNS_Deregister(m, &ptr->ar);
                        }
                }
        else
                LogMsg("xD2DRemoveFromCache: Unexpected result %d", result);
        }

mDNSlocal void xD2DServiceResolved(mDNS *const m, D2DStatus result, D2DServiceInstance instanceHandle, D2DTransportType transportType, const Byte *key, size_t keySize, const Byte *value, size_t valueSize)
        {
        (void)m;
        (void)key;
        (void)keySize;
        (void)value;
        (void)valueSize;
        
        if (result == kD2DSuccess) 
                {
                LogInfo("xD2DServiceResolved: Starting up PAN connection for %p", instanceHandle);
                CHECK_D2D_FUNCTION(D2DRetain) D2DRetain(instanceHandle, transportType);
                }
        else LogMsg("xD2DServiceResolved: Unexpected result %d", result);
        }

mDNSlocal void xD2DRetainHappened(mDNS *const m, D2DStatus result, D2DServiceInstance instanceHandle, D2DTransportType transportType, const Byte *key, size_t keySize, const Byte *value, size_t valueSize)
        {
        (void)m;
        (void)instanceHandle;
        (void)transportType;
        (void)key;
        (void)keySize;
        (void)value;
        (void)valueSize;
        
        if (result == kD2DSuccess) LogInfo("xD2DRetainHappened: Opening up PAN connection for %p", instanceHandle);
        else LogMsg("xD2DRetainHappened: Unexpected result %d", result);
        }

mDNSlocal void xD2DReleaseHappened(mDNS *const m, D2DStatus result, D2DServiceInstance instanceHandle, D2DTransportType transportType, const Byte *key, size_t keySize, const Byte *value, size_t valueSize)
        {
        (void)m;
        (void)instanceHandle;
        (void)transportType;
        (void)key;
        (void)keySize;
        (void)value;
        (void)valueSize;
        
        if (result == kD2DSuccess) LogInfo("xD2DReleaseHappened: Closing PAN connection for %p", instanceHandle);
        else LogMsg("xD2DReleaseHappened: Unexpected result %d", result);
        }

mDNSlocal void xD2DServiceCallback(D2DServiceEvent event, D2DStatus result, D2DServiceInstance instanceHandle, D2DTransportType transportType, const Byte *key, size_t keySize, const Byte *value, size_t valueSize, void *userData)
        {
        mDNS *m = (mDNS *) userData;
        const char *eventString = "unknown";
        
        KQueueLock(m);
        
        if (keySize   > 0xFFFF) LogMsg("xD2DServiceCallback: keySize too large: %u", keySize);
        if (valueSize > 0xFFFF) LogMsg("xD2DServiceCallback: valueSize too large: %u", valueSize);
                
        switch (event)
                {
                case D2DServiceFound:
                        eventString = "D2DServiceFound";
                        break;
                case D2DServiceLost:
                        eventString = "D2DServiceLost";
                        break;
                case D2DServiceResolved:
                        eventString = "D2DServiceResolved";
                        break;
                case D2DServiceRetained:
                        eventString = "D2DServiceRetained";
                        break;
                case D2DServiceReleased:
                        eventString = "D2DServiceReleased";
                        break;
                default:
                        break;
                }
        
        LogInfo("xD2DServiceCallback: event=%s result=%d instanceHandle=%p transportType=%d LHS=%p (%u) RHS=%p (%u) userData=%p", eventString, result, instanceHandle, transportType, key, keySize, value, valueSize, userData);
        PrintHelper(__func__, (mDNSu8 *)key, (mDNSu16)keySize, (mDNSu8 *)value, (mDNSu16)valueSize);
        
        switch (event)
                {
                case D2DServiceFound:
                        xD2DAddToCache(m, result, instanceHandle, transportType, key, keySize, value, valueSize);
                        break;
                case D2DServiceLost:
                        xD2DRemoveFromCache(m, result, instanceHandle, transportType, key, keySize, value, valueSize);
                        break;
                case D2DServiceResolved:
                        xD2DServiceResolved(m, result, instanceHandle, transportType, key, keySize, value, valueSize);
                        break;
                case D2DServiceRetained:
                        xD2DRetainHappened(m, result, instanceHandle, transportType, key, keySize, value, valueSize);
                        break;
                case D2DServiceReleased:
                        xD2DReleaseHappened(m, result, instanceHandle, transportType, key, keySize, value, valueSize);
                        break;
                default:
                        break;
                }
        
        // Need to tickle the main kqueue loop to potentially handle records we removed or added.
        KQueueUnlock(m, "xD2DServiceCallback");
        }

mDNSexport void external_start_browsing_for_service(mDNS *const m, const domainname *const typeDomain, DNS_TypeValues qtype)
        {
        (void)m;
        domainname lower;
        
        if (qtype == kDNSServiceType_A || qtype == kDNSServiceType_AAAA)
                {
                LogInfo("external_start_browsing_for_service: ignoring address record");
                return;
                }
        
        DomainnameToLower(typeDomain, &lower);
        
        if (!D2DBrowseListRefCount(&lower, qtype))
                {
                LogInfo("external_start_browsing_for_service: Starting browse for: %##s %s", lower.c, DNSTypeName(qtype));
                mDNSu8 *end = DNSNameCompressionBuildLHS(&lower, qtype);
                PrintHelper(__func__, compression_lhs, end - compression_lhs, mDNSNULL, 0);
                CHECK_D2D_FUNCTION(D2DStartBrowsingForKey) D2DStartBrowsingForKey(compression_lhs, end - compression_lhs);
                }
        D2DBrowseListRetain(&lower, qtype);
        }

mDNSexport void external_stop_browsing_for_service(mDNS *const m, const domainname *const typeDomain, DNS_TypeValues qtype)
        {
        domainname lower;
        
        if (qtype == kDNSServiceType_A || qtype == kDNSServiceType_AAAA)
                {
                LogInfo("external_stop_browsing_for_service: ignoring address record");
                return;
                }
        
        DomainnameToLower(typeDomain, &lower);
        
        D2DBrowseListRelease(&lower, qtype);
        if (!D2DBrowseListRefCount(&lower, qtype))
                {
                LogInfo("external_stop_browsing_for_service: Stopping browse for: %##s %s", lower.c, DNSTypeName(qtype));
                mDNSu8 *end = DNSNameCompressionBuildLHS(&lower, qtype);
                PrintHelper(__func__, compression_lhs, end - compression_lhs, mDNSNULL, 0);
                CHECK_D2D_FUNCTION(D2DStopBrowsingForKey) D2DStopBrowsingForKey(compression_lhs, end - compression_lhs);
                xD2DClearCache(m, &lower);
                }
        }

mDNSexport void external_start_advertising_service(const ResourceRecord *const resourceRecord)
        {
        domainname lower;
        mDNSu8 *rhs = NULL;
        mDNSu8 *end = NULL;
        DomainnameToLower(resourceRecord->name, &lower);
        
        LogInfo("external_start_advertising_service: %s", RRDisplayString(&mDNSStorage, resourceRecord));
        if (resourceRecord->rrtype == kDNSServiceType_A || resourceRecord->rrtype == kDNSServiceType_AAAA)
                {
                LogInfo("external_start_advertising_service: ignoring address record");
                return;
                }
        rhs = DNSNameCompressionBuildLHS(&lower, resourceRecord->rrtype);
        end = DNSNameCompressionBuildRHS(rhs, resourceRecord);
        PrintHelper(__func__, compression_lhs, rhs - compression_lhs, rhs, end - rhs);
        CHECK_D2D_FUNCTION(D2DStartAdvertisingPair) D2DStartAdvertisingPair(compression_lhs, rhs - compression_lhs, rhs, end - rhs);
        }

mDNSexport void external_stop_advertising_service(const ResourceRecord *const resourceRecord)
        {
        domainname lower;
        mDNSu8 *rhs = NULL;
        mDNSu8 *end = NULL;
        DomainnameToLower(resourceRecord->name, &lower);
        
        LogInfo("external_stop_advertising_service: %s", RRDisplayString(&mDNSStorage, resourceRecord));
        if (resourceRecord->rrtype == kDNSServiceType_A || resourceRecord->rrtype == kDNSServiceType_AAAA)
                {
                LogInfo("external_stop_advertising_service: ignoring address record");
                return;
                }
        rhs = DNSNameCompressionBuildLHS(&lower, resourceRecord->rrtype);
        end = DNSNameCompressionBuildRHS(rhs, resourceRecord);
        PrintHelper(__func__, compression_lhs, rhs - compression_lhs, rhs, end - rhs);
        CHECK_D2D_FUNCTION(D2DStopAdvertisingPair) D2DStopAdvertisingPair(compression_lhs, rhs - compression_lhs, rhs, end - rhs);
        }

mDNSexport void external_start_resolving_service(const domainname *const fqdn)
        {
        domainname lower;
        mDNSu8 *rhs = NULL;
        mDNSu8 *end = NULL;
        DomainnameToLower(SkipLeadingLabels(fqdn, 1), &lower);
        
        LogInfo("external_start_resolving_service: %##s", fqdn->c);
        rhs = DNSNameCompressionBuildLHS(&lower, kDNSType_PTR);
        end = putDomainNameAsLabels(&compression_base_msg, rhs, compression_limit, fqdn);
        PrintHelper(__func__, compression_lhs, rhs - compression_lhs, rhs, end - rhs);
        CHECK_D2D_FUNCTION(D2DStartResolvingPair) D2DStartResolvingPair(compression_lhs, rhs - compression_lhs, rhs, end - rhs);
        }

mDNSexport void external_stop_resolving_service(const domainname *const fqdn) 
        { 
        domainname lower;
        mDNSu8 *rhs = NULL;
        mDNSu8 *end = NULL;
        DomainnameToLower(SkipLeadingLabels(fqdn, 1), &lower);
        
        LogInfo("external_stop_resolving_service: %##s", fqdn->c);
        rhs = DNSNameCompressionBuildLHS(&lower, kDNSType_PTR);
        end = putDomainNameAsLabels(&compression_base_msg, rhs, compression_limit, fqdn);
        PrintHelper(__func__, compression_lhs, rhs - compression_lhs, rhs, end - rhs);
        CHECK_D2D_FUNCTION(D2DStopResolvingPair) D2DStopResolvingPair(compression_lhs, rhs - compression_lhs, rhs, end - rhs);
        }

#elif APPLE_OSX_mDNSResponder

mDNSexport void external_start_browsing_for_service(mDNS *const m, const domainname *const type, DNS_TypeValues qtype) { (void)m; (void)type; (void)qtype; }
mDNSexport void external_stop_browsing_for_service(mDNS *const m, const domainname *const type, DNS_TypeValues qtype) { (void)m; (void)type; (void)qtype; }
mDNSexport void external_start_advertising_service(const ResourceRecord *const resourceRecord) { (void)resourceRecord; }
mDNSexport void external_stop_advertising_service(const ResourceRecord *const resourceRecord) { (void)resourceRecord; }
mDNSexport void external_start_resolving_service(const domainname *const fqdn)  { (void)fqdn; }
mDNSexport void external_stop_resolving_service(const domainname *const fqdn)  { (void)fqdn; }

#endif // ! NO_D2D

// ***************************************************************************
// Functions

#if COMPILER_LIKES_PRAGMA_MARK
#pragma mark -
#pragma mark - Utility Functions
#endif

// We only attempt to send and receive multicast packets on interfaces that are
// (a) flagged as multicast-capable
// (b) *not* flagged as point-to-point (e.g. modem)
// Typically point-to-point interfaces are modems (including mobile-phone pseudo-modems), and we don't want
// to run up the user's bill sending multicast traffic over a link where there's only a single device at the
// other end, and that device (e.g. a modem bank) is probably not answering Multicast DNS queries anyway.
#define MulticastInterface(i) (((i)->ifa_flags & IFF_MULTICAST) && !((i)->ifa_flags & IFF_POINTOPOINT))

mDNSexport void NotifyOfElusiveBug(const char *title, const char *msg)  // Both strings are UTF-8 text
        {
        static int notifyCount = 0;
        if (notifyCount) return;

        // If we display our alert early in the boot process, then it vanishes once the desktop appears.
        // To avoid this, we don't try to display alerts in the first three minutes after boot.
        if ((mDNSu32)(mDNSPlatformRawTime()) < (mDNSu32)(mDNSPlatformOneSecond * 180)) return;

        // Unless ForceAlerts is defined, we only show these bug report alerts on machines that have a 17.x.x.x address
        #if !ForceAlerts
                {
                // Determine if we're at Apple (17.*.*.*)
                extern mDNS mDNSStorage;
                NetworkInterfaceInfoOSX *i;
                for (i = mDNSStorage.p->InterfaceList; i; i = i->next)
                        if (i->ifinfo.ip.type == mDNSAddrType_IPv4 && i->ifinfo.ip.ip.v4.b[0] == 17)
                                break;
                if (!i) return; // If not at Apple, don't show the alert
                }
        #endif

        LogMsg("%s", title);
        LogMsg("%s", msg);
        // Display a notification to the user
        notifyCount++;

#ifndef NO_CFUSERNOTIFICATION
        mDNSNotify(title, msg);
#endif /* NO_CFUSERNOTIFICATION */
        }

mDNSlocal struct ifaddrs *myGetIfAddrs(int refresh)
        {
        static struct ifaddrs *ifa = NULL;

        if (refresh && ifa)
                {
                freeifaddrs(ifa);
                ifa = NULL;
                }

        if (ifa == NULL) getifaddrs(&ifa);

        return ifa;
        }

// To match *either* a v4 or v6 instance of this interface name, pass AF_UNSPEC for type
mDNSlocal NetworkInterfaceInfoOSX *SearchForInterfaceByName(mDNS *const m, const char *ifname, int type)
        {
        NetworkInterfaceInfoOSX *i;
        for (i = m->p->InterfaceList; i; i = i->next)
                if (i->Exists && !strcmp(i->ifinfo.ifname, ifname) &&
                        ((type == AF_UNSPEC                                         ) ||
                         (type == AF_INET  && i->ifinfo.ip.type == mDNSAddrType_IPv4) ||
                         (type == AF_INET6 && i->ifinfo.ip.type == mDNSAddrType_IPv6))) return(i);
        return(NULL);
        }

mDNSlocal int myIfIndexToName(u_short ifindex, char *name)
        {
        struct ifaddrs *ifa;
        for (ifa = myGetIfAddrs(0); ifa; ifa = ifa->ifa_next)
                if (ifa->ifa_addr->sa_family == AF_LINK)
                        if (((struct sockaddr_dl*)ifa->ifa_addr)->sdl_index == ifindex)
                                { strlcpy(name, ifa->ifa_name, IF_NAMESIZE); return 0; }
        return -1;
        }

mDNSexport NetworkInterfaceInfoOSX *IfindexToInterfaceInfoOSX(const mDNS *const m, mDNSInterfaceID ifindex)
{
        mDNSu32 scope_id = (mDNSu32)(uintptr_t)ifindex;
        NetworkInterfaceInfoOSX *i;

        // Don't get tricked by inactive interfaces
        for (i = m->p->InterfaceList; i; i = i->next)
                if (i->Registered && i->scope_id == scope_id) return(i);

        return mDNSNULL;
}

mDNSexport mDNSInterfaceID mDNSPlatformInterfaceIDfromInterfaceIndex(mDNS *const m, mDNSu32 ifindex)
        {
        if (ifindex == kDNSServiceInterfaceIndexLocalOnly) return(mDNSInterface_LocalOnly);
        if (ifindex == kDNSServiceInterfaceIndexP2P      ) return(mDNSInterface_P2P);
        if (ifindex == kDNSServiceInterfaceIndexAny      ) return(mDNSNULL);

        NetworkInterfaceInfoOSX* ifi = IfindexToInterfaceInfoOSX(m, (mDNSInterfaceID)(uintptr_t)ifindex);
        if (!ifi)
                {
                // Not found. Make sure our interface list is up to date, then try again.
                LogInfo("mDNSPlatformInterfaceIDfromInterfaceIndex: InterfaceID for interface index %d not found; Updating interface list", ifindex);
                mDNSMacOSXNetworkChanged(m);
                ifi = IfindexToInterfaceInfoOSX(m, (mDNSInterfaceID)(uintptr_t)ifindex);
                }

        if (!ifi) return(mDNSNULL);     
        
        return(ifi->ifinfo.InterfaceID);
        }


mDNSexport mDNSu32 mDNSPlatformInterfaceIndexfromInterfaceID(mDNS *const m, mDNSInterfaceID id)
        {
        NetworkInterfaceInfoOSX *i;
        if (id == mDNSInterface_LocalOnly) return(kDNSServiceInterfaceIndexLocalOnly);
        if (id == mDNSInterface_P2P      ) return(kDNSServiceInterfaceIndexP2P);
        if (id == mDNSInterface_Any      ) return(0);

        mDNSu32 scope_id = (mDNSu32)(uintptr_t)id;

        // Don't use i->Registered here, because we DO want to find inactive interfaces, which have no Registered set
        for (i = m->p->InterfaceList; i; i = i->next)
                if (i->scope_id == scope_id) return(i->scope_id);

        // Not found. Make sure our interface list is up to date, then try again.
        LogInfo("Interface index for InterfaceID %p not found; Updating interface list", id);
        mDNSMacOSXNetworkChanged(m);
        for (i = m->p->InterfaceList; i; i = i->next)
                if (i->scope_id == scope_id) return(i->scope_id);

        return(0);
        }

#if APPLE_OSX_mDNSResponder
mDNSexport void mDNSASLLog(uuid_t *uuid, const char *subdomain, const char *result, const char *signature, const char *fmt, ...)
        {
        if (OSXVers < OSXVers_10_6_SnowLeopard)         return;

        static char             buffer[512];
        aslmsg                  asl_msg = asl_new(ASL_TYPE_MSG);

        if (!asl_msg)   { LogMsg("mDNSASLLog: asl_new failed"); return; }
        if (uuid)
                {
                char            uuidStr[37];
                uuid_unparse(*uuid, uuidStr);
                asl_set         (asl_msg, "com.apple.message.uuid", uuidStr);
                }

        static char     domainBase[] = "com.apple.mDNSResponder.%s";
        mDNS_snprintf   (buffer, sizeof(buffer), domainBase, subdomain);
        asl_set                 (asl_msg, "com.apple.message.domain", buffer);

        if (result)             asl_set(asl_msg, "com.apple.message.result", result);
        if (signature)  asl_set(asl_msg, "com.apple.message.signature", signature);

        va_list ptr;
        va_start(ptr,fmt);
        mDNS_vsnprintf(buffer, sizeof(buffer), fmt, ptr);
        va_end(ptr);

        int     old_filter = asl_set_filter(NULL,ASL_FILTER_MASK_UPTO(ASL_LEVEL_DEBUG));
        asl_log(NULL, asl_msg, ASL_LEVEL_DEBUG, "%s", buffer);
        asl_set_filter(NULL, old_filter);
        asl_free(asl_msg);
        }
#endif // APPLE_OSX_mDNSResponder

#if COMPILER_LIKES_PRAGMA_MARK
#pragma mark -
#pragma mark - UDP & TCP send & receive
#endif

mDNSlocal mDNSBool AddrRequiresPPPConnection(const struct sockaddr *addr)
        {
        mDNSBool result = mDNSfalse;
        SCNetworkConnectionFlags flags;
        SCNetworkReachabilityRef ReachRef = NULL;

        ReachRef = SCNetworkReachabilityCreateWithAddress(kCFAllocatorDefault, addr);
        if (!ReachRef) { LogMsg("ERROR: RequiresConnection - SCNetworkReachabilityCreateWithAddress"); goto end; }
        if (!SCNetworkReachabilityGetFlags(ReachRef, &flags)) { LogMsg("ERROR: AddrRequiresPPPConnection - SCNetworkReachabilityGetFlags"); goto end; }
        result = flags & kSCNetworkFlagsConnectionRequired;

        end:
        if (ReachRef) CFRelease(ReachRef);
        return result;
        }

// Note: If InterfaceID is NULL, it means, "send this packet through our anonymous unicast socket"
// Note: If InterfaceID is non-NULL it means, "send this packet through our port 5353 socket on the specified interface"
// OR send via our primary v4 unicast socket
// UPDATE: The UDPSocket *src parameter now allows the caller to specify the source socket
mDNSexport mStatus mDNSPlatformSendUDP(const mDNS *const m, const void *const msg, const mDNSu8 *const end,
        mDNSInterfaceID InterfaceID, UDPSocket *src, const mDNSAddr *dst, mDNSIPPort dstPort)
        {
        NetworkInterfaceInfoOSX *info = mDNSNULL;
        struct sockaddr_storage to;
        int s = -1, err;
        mStatus result = mStatus_NoError;

        if (InterfaceID)
                {
                info = IfindexToInterfaceInfoOSX(m, InterfaceID);
                if (info == NULL)
                        {
                        LogMsg("mDNSPlatformSendUDP: Invalid interface index %p", InterfaceID);
                        return mStatus_BadParamErr;
                        }
                }

        char *ifa_name = InterfaceID ? info->ifinfo.ifname : "unicast";

        if (dst->type == mDNSAddrType_IPv4)
                {
                struct sockaddr_in *sin_to = (struct sockaddr_in*)&to;
                sin_to->sin_len            = sizeof(*sin_to);
                sin_to->sin_family         = AF_INET;
                sin_to->sin_port           = dstPort.NotAnInteger;
                sin_to->sin_addr.s_addr    = dst->ip.v4.NotAnInteger;
                s = (src ? src->ss : m->p->permanentsockets).sktv4;

                if (info)       // Specify outgoing interface
                        {
                        if (!mDNSAddrIsDNSMulticast(dst))
                                {
                                #ifdef IP_BOUND_IF
                                        if (info->scope_id == 0)
                                                LogInfo("IP_BOUND_IF socket option not set -- info %p (%s) scope_id is zero", info, ifa_name);
                                        else
                                                setsockopt(s, IPPROTO_IP, IP_BOUND_IF, &info->scope_id, sizeof(info->scope_id));
                                #else
                                        {
                                        static int displayed = 0;
                                        if (displayed < 1000)
                                                {
                                                displayed++;
                                                LogInfo("IP_BOUND_IF socket option not defined -- cannot specify interface for unicast packets");
                                                }
                                        }
                                #endif
                                }
                        else
                                #ifdef IP_MULTICAST_IFINDEX
                                {
                                err = setsockopt(s, IPPROTO_IP, IP_MULTICAST_IFINDEX, &info->scope_id, sizeof(info->scope_id));
                                // We get an error when we compile on a machine that supports this option and run the binary on
                                // a different machine that does not support it
                                if (err < 0)
                                        {
                                        if (errno != ENOPROTOOPT) LogInfo("mDNSPlatformSendUDP: setsockopt: IP_MUTLTICAST_IFINDEX returned %d", errno);
                                        err = setsockopt(s, IPPROTO_IP, IP_MULTICAST_IF, &info->ifa_v4addr, sizeof(info->ifa_v4addr));
                                        if (err < 0 && !m->p->NetworkChanged)
                                                LogMsg("setsockopt - IP_MULTICAST_IF error %.4a %d errno %d (%s)", &info->ifa_v4addr, err, errno, strerror(errno));
                                        }
                                }
                                #else
                                {
                                err = setsockopt(s, IPPROTO_IP, IP_MULTICAST_IF, &info->ifa_v4addr, sizeof(info->ifa_v4addr));
                                if (err < 0 && !m->p->NetworkChanged)
                                        LogMsg("setsockopt - IP_MULTICAST_IF error %.4a %d errno %d (%s)", &info->ifa_v4addr, err, errno, strerror(errno));

                                }
                                #endif
                        }
                }
#ifndef NO_IPV6
        else if (dst->type == mDNSAddrType_IPv6)
                {
                struct sockaddr_in6 *sin6_to = (struct sockaddr_in6*)&to;
                sin6_to->sin6_len            = sizeof(*sin6_to);
                sin6_to->sin6_family         = AF_INET6;
                sin6_to->sin6_port           = dstPort.NotAnInteger;
                sin6_to->sin6_flowinfo       = 0;
                sin6_to->sin6_addr           = *(struct in6_addr*)&dst->ip.v6;
                sin6_to->sin6_scope_id       = info ? info->scope_id : 0;
                s = (src ? src->ss : m->p->permanentsockets).sktv6;
                if (info && mDNSAddrIsDNSMulticast(dst))        // Specify outgoing interface
                        {
                        err = setsockopt(s, IPPROTO_IPV6, IPV6_MULTICAST_IF, &info->scope_id, sizeof(info->scope_id));
                        if (err < 0) LogMsg("setsockopt - IPV6_MULTICAST_IF error %d errno %d (%s)", err, errno, strerror(errno));
                        }
                }
#endif
        else
                {
                LogMsg("mDNSPlatformSendUDP: dst is not an IPv4 or IPv6 address!");
#if ForceAlerts
                *(long*)0 = 0;
#endif
                return mStatus_BadParamErr;
                }

        if (s >= 0)
                verbosedebugf("mDNSPlatformSendUDP: sending on InterfaceID %p %5s/%ld to %#a:%d skt %d",
                        InterfaceID, ifa_name, dst->type, dst, mDNSVal16(dstPort), s);
        else
                verbosedebugf("mDNSPlatformSendUDP: NOT sending on InterfaceID %p %5s/%ld (socket of this type not available)",
                        InterfaceID, ifa_name, dst->type, dst, mDNSVal16(dstPort));

        // Note: When sending, mDNSCore may often ask us to send both a v4 multicast packet and then a v6 multicast packet
        // If we don't have the corresponding type of socket available, then return mStatus_Invalid
        if (s < 0) return(mStatus_Invalid);

        err = sendto(s, msg, (UInt8*)end - (UInt8*)msg, 0, (struct sockaddr *)&to, to.ss_len);
        if (err < 0)
                {
                static int MessageCount = 0;
                // Don't report EHOSTDOWN (i.e. ARP failure), ENETDOWN, or no route to host for unicast destinations
                if (!mDNSAddressIsAllDNSLinkGroup(dst))
                        if (errno == EHOSTDOWN || errno == ENETDOWN || errno == EHOSTUNREACH || errno == ENETUNREACH) return(mStatus_TransientErr);
                // Don't report EHOSTUNREACH in the first three minutes after boot
                // This is because mDNSResponder intentionally starts up early in the boot process (See <rdar://problem/3409090>)
                // but this means that sometimes it starts before configd has finished setting up the multicast routing entries.
                if (errno == EHOSTUNREACH && (mDNSu32)(mDNSPlatformRawTime()) < (mDNSu32)(mDNSPlatformOneSecond * 180)) return(mStatus_TransientErr);
                // Don't report EADDRNOTAVAIL ("Can't assign requested address") if we're in the middle of a network configuration change
                if (errno == EADDRNOTAVAIL && m->p->NetworkChanged) return(mStatus_TransientErr);
                if (MessageCount < 1000)
                        {
                        MessageCount++;
                        if (errno == EHOSTUNREACH || errno == EADDRNOTAVAIL || errno == ENETDOWN)
                                LogInfo("mDNSPlatformSendUDP sendto(%d) failed to send packet on InterfaceID %p %5s/%d to %#a:%d skt %d error %d errno %d (%s) %lu",
                                        s, InterfaceID, ifa_name, dst->type, dst, mDNSVal16(dstPort), s, err, errno, strerror(errno), (mDNSu32)(m->timenow));
                        else
                                LogMsg("mDNSPlatformSendUDP sendto(%d) failed to send packet on InterfaceID %p %5s/%d to %#a:%d skt %d error %d errno %d (%s) %lu",
                                        s, InterfaceID, ifa_name, dst->type, dst, mDNSVal16(dstPort), s, err, errno, strerror(errno), (mDNSu32)(m->timenow));
                        }
                result = mStatus_UnknownErr;
                }

#ifdef IP_BOUND_IF
        if (dst->type == mDNSAddrType_IPv4 && info && !mDNSAddrIsDNSMulticast(dst))
                {
                static const mDNSu32 ifindex = 0;
                setsockopt(s, IPPROTO_IP, IP_BOUND_IF, &ifindex, sizeof(ifindex));
                }
#endif

        return(result);
        }

mDNSlocal ssize_t myrecvfrom(const int s, void *const buffer, const size_t max,
        struct sockaddr *const from, size_t *const fromlen, mDNSAddr *dstaddr, char ifname[IF_NAMESIZE], mDNSu8 *ttl)
        {
        static unsigned int numLogMessages = 0;
        struct iovec databuffers = { (char *)buffer, max };
        struct msghdr   msg;
        ssize_t         n;
        struct cmsghdr *cmPtr;
        char            ancillary[1024];

        *ttl = 255;  // If kernel fails to provide TTL data (e.g. Jaguar doesn't) then assume the TTL was 255 as it should be

        // Set up the message
        msg.msg_name       = (caddr_t)from;
        msg.msg_namelen    = *fromlen;
        msg.msg_iov        = &databuffers;
        msg.msg_iovlen     = 1;
        msg.msg_control    = (caddr_t)&ancillary;
        msg.msg_controllen = sizeof(ancillary);
        msg.msg_flags      = 0;

        // Receive the data
        n = recvmsg(s, &msg, 0);
        if (n<0)
                {
                if (errno != EWOULDBLOCK && numLogMessages++ < 100) LogMsg("mDNSMacOSX.c: recvmsg(%d) returned error %d errno %d", s, n, errno);
                return(-1);
                }
        if (msg.msg_controllen < (int)sizeof(struct cmsghdr))
                {
                if (numLogMessages++ < 100) LogMsg("mDNSMacOSX.c: recvmsg(%d) returned %d msg.msg_controllen %d < sizeof(struct cmsghdr) %lu",
                        s, n, msg.msg_controllen, sizeof(struct cmsghdr));
                return(-1);
                }
        if (msg.msg_flags & MSG_CTRUNC)
                {
                if (numLogMessages++ < 100) LogMsg("mDNSMacOSX.c: recvmsg(%d) msg.msg_flags & MSG_CTRUNC", s);
                return(-1);
                }

        *fromlen = msg.msg_namelen;

        // Parse each option out of the ancillary data.
        for (cmPtr = CMSG_FIRSTHDR(&msg); cmPtr; cmPtr = CMSG_NXTHDR(&msg, cmPtr))
                {
                // debugf("myrecvfrom cmsg_level %d cmsg_type %d", cmPtr->cmsg_level, cmPtr->cmsg_type);
                if (cmPtr->cmsg_level == IPPROTO_IP && cmPtr->cmsg_type == IP_RECVDSTADDR)
                        {
                        dstaddr->type = mDNSAddrType_IPv4;
                        dstaddr->ip.v4 = *(mDNSv4Addr*)CMSG_DATA(cmPtr);
                        //LogMsg("mDNSMacOSX.c: recvmsg IP_RECVDSTADDR %.4a", &dstaddr->ip.v4);
                        }
                if (cmPtr->cmsg_level == IPPROTO_IP && cmPtr->cmsg_type == IP_RECVIF)
                        {
                        struct sockaddr_dl *sdl = (struct sockaddr_dl *)CMSG_DATA(cmPtr);
                        if (sdl->sdl_nlen < IF_NAMESIZE)
                                {
                                mDNSPlatformMemCopy(ifname, sdl->sdl_data, sdl->sdl_nlen);
                                ifname[sdl->sdl_nlen] = 0;
                                // debugf("IP_RECVIF sdl_index %d, sdl_data %s len %d", sdl->sdl_index, ifname, sdl->sdl_nlen);
                                }
                        }
                if (cmPtr->cmsg_level == IPPROTO_IP && cmPtr->cmsg_type == IP_RECVTTL)
                        *ttl = *(u_char*)CMSG_DATA(cmPtr);
                if (cmPtr->cmsg_level == IPPROTO_IPV6 && cmPtr->cmsg_type == IPV6_PKTINFO)
                        {
                        struct in6_pktinfo *ip6_info = (struct in6_pktinfo*)CMSG_DATA(cmPtr);
                        dstaddr->type = mDNSAddrType_IPv6;
                        dstaddr->ip.v6 = *(mDNSv6Addr*)&ip6_info->ipi6_addr;
                        myIfIndexToName(ip6_info->ipi6_ifindex, ifname);
                        }
                if (cmPtr->cmsg_level == IPPROTO_IPV6 && cmPtr->cmsg_type == IPV6_HOPLIMIT)
                        *ttl = *(int*)CMSG_DATA(cmPtr);
                }

        return(n);
        }

mDNSlocal void myKQSocketCallBack(int s1, short filter, void *context)
        {
        KQSocketSet *const ss = (KQSocketSet *)context;
        mDNS *const m = ss->m;
        int err = 0, count = 0, closed = 0;

        if (filter != EVFILT_READ)
                LogMsg("myKQSocketCallBack: Why is filter %d not EVFILT_READ (%d)?", filter, EVFILT_READ);

        if (s1 != ss->sktv4
#ifndef NO_IPV6
                && s1 != ss->sktv6
#endif
                )
                {
                LogMsg("myKQSocketCallBack: native socket %d", s1);
                LogMsg("myKQSocketCallBack: sktv4 %d", ss->sktv4);
#ifndef NO_IPV6
                LogMsg("myKQSocketCallBack: sktv6 %d", ss->sktv6);
#endif
                }

        while (!closed)
                {
                mDNSAddr senderAddr, destAddr;
                mDNSIPPort senderPort;
                struct sockaddr_storage from;
                size_t fromlen = sizeof(from);
                char packetifname[IF_NAMESIZE] = "";
                mDNSu8 ttl;
                err = myrecvfrom(s1, &m->imsg, sizeof(m->imsg), (struct sockaddr *)&from, &fromlen, &destAddr, packetifname, &ttl);
                if (err < 0) break;

                count++;
                if (from.ss_family == AF_INET)
                        {
                        struct sockaddr_in *s = (struct sockaddr_in*)&from;
                        senderAddr.type = mDNSAddrType_IPv4;
                        senderAddr.ip.v4.NotAnInteger = s->sin_addr.s_addr;
                        senderPort.NotAnInteger = s->sin_port;
                        //LogInfo("myKQSocketCallBack received IPv4 packet from %#-15a to %#-15a on skt %d %s", &senderAddr, &destAddr, s1, packetifname);
                        }
                else if (from.ss_family == AF_INET6)
                        {
                        struct sockaddr_in6 *sin6 = (struct sockaddr_in6*)&from;
                        senderAddr.type = mDNSAddrType_IPv6;
                        senderAddr.ip.v6 = *(mDNSv6Addr*)&sin6->sin6_addr;
                        senderPort.NotAnInteger = sin6->sin6_port;
                        //LogInfo("myKQSocketCallBack received IPv6 packet from %#-15a to %#-15a on skt %d %s", &senderAddr, &destAddr, s1, packetifname);
                        }
                else
                        {
                        LogMsg("myKQSocketCallBack from is unknown address family %d", from.ss_family);
                        return;
                        }

                // Note: When handling multiple packets in a batch, MUST reset InterfaceID before handling each packet
                mDNSInterfaceID InterfaceID = mDNSNULL;
                //NetworkInterfaceInfo *intf = m->HostInterfaces;
                //while (intf && strcmp(intf->ifname, packetifname)) intf = intf->next;

                NetworkInterfaceInfoOSX *intf = m->p->InterfaceList;
                while (intf && strcmp(intf->ifinfo.ifname, packetifname)) intf = intf->next;

                // When going to sleep we deregister all our interfaces, but if the machine
                // takes a few seconds to sleep we may continue to receive multicasts
                // during that time, which would confuse mDNSCoreReceive, because as far
                // as it's concerned, we should have no active interfaces any more.
                // Hence we ignore multicasts for which we can find no matching InterfaceID.
                if (intf) InterfaceID = intf->ifinfo.InterfaceID;
                else if (mDNSAddrIsDNSMulticast(&destAddr)) continue;

//              LogMsg("myKQSocketCallBack got packet from %#a to %#a on interface %#a/%s",
//                      &senderAddr, &destAddr, &ss->info->ifinfo.ip, ss->info->ifinfo.ifname);

                // mDNSCoreReceive may close the socket we're reading from.  We must break out of our
                // loop when that happens, or we may try to read from an invalid FD.  We do this by
                // setting the closeFlag pointer in the socketset, so CloseSocketSet can inform us
                // if it closes the socketset.
                ss->closeFlag = &closed;

                mDNSCoreReceive(m, &m->imsg, (unsigned char*)&m->imsg + err, &senderAddr, senderPort, &destAddr, ss->port, InterfaceID);

                // if we didn't close, we can safely dereference the socketset, and should to
                // reset the closeFlag, since it points to something on the stack
                if (!closed) ss->closeFlag = mDNSNULL;
                }

        if (err < 0 && (errno != EWOULDBLOCK || count == 0))
                {
                // Something is busted here.
                // kqueue says there is a packet, but myrecvfrom says there is not.
                // Try calling select() to get another opinion.
                // Find out about other socket parameter that can help understand why select() says the socket is ready for read
                // All of this is racy, as data may have arrived after the call to select()
                static unsigned int numLogMessages = 0;
                int save_errno = errno;
                int so_error = -1;
                int so_nread = -1;
                int fionread = -1;
                socklen_t solen = sizeof(int);
                fd_set readfds;
                struct timeval timeout;
                int selectresult;
                FD_ZERO(&readfds);
                FD_SET(s1, &readfds);
                timeout.tv_sec  = 0;
                timeout.tv_usec = 0;
                selectresult = select(s1+1, &readfds, NULL, NULL, &timeout);
                if (getsockopt(s1, SOL_SOCKET, SO_ERROR, &so_error, &solen) == -1)
                        LogMsg("myKQSocketCallBack getsockopt(SO_ERROR) error %d", errno);
                if (getsockopt(s1, SOL_SOCKET, SO_NREAD, &so_nread, &solen) == -1)
                        LogMsg("myKQSocketCallBack getsockopt(SO_NREAD) error %d", errno);
                if (ioctl(s1, FIONREAD, &fionread) == -1)
                        LogMsg("myKQSocketCallBack ioctl(FIONREAD) error %d", errno);
                if (numLogMessages++ < 100)
                        LogMsg("myKQSocketCallBack recvfrom skt %d error %d errno %d (%s) select %d (%spackets waiting) so_error %d so_nread %d fionread %d count %d",
                                s1, err, save_errno, strerror(save_errno), selectresult, FD_ISSET(s1, &readfds) ? "" : "*NO* ", so_error, so_nread, fionread, count);
                if (numLogMessages > 5)
                        NotifyOfElusiveBug("Flaw in Kernel (select/recvfrom mismatch)",
                                "Congratulations, you've reproduced an elusive bug.\r"
                                "Please contact the current assignee of <rdar://problem/3375328>.\r"
                                "Alternatively, you can send email to radar-3387020@group.apple.com. (Note number is different.)\r"
                                "If possible, please leave your machine undisturbed so that someone can come to investigate the problem.");

                sleep(1);               // After logging this error, rate limit so we don't flood syslog
                }
        }

// TCP socket support

typedef enum
        {
        handshake_required,
        handshake_in_progress,
        handshake_completed,
        handshake_to_be_closed
        } handshakeStatus;
        
struct TCPSocket_struct
        {
        TCPSocketFlags flags;           // MUST BE FIRST FIELD -- mDNSCore expects every TCPSocket_struct to begin with TCPSocketFlags flags
        TCPConnectionCallback callback;
        int fd;
        KQueueEntry *kqEntry;   
        KQSocketSet ss;
#ifndef NO_SECURITYFRAMEWORK
        SSLContextRef tlsContext;
        pthread_t handshake_thread;
#endif /* NO_SECURITYFRAMEWORK */
        domainname hostname;
        void *context;
        mDNSBool setup;
        mDNSBool connected;
        handshakeStatus handshake;
        mDNS *m; // So we can call KQueueLock from the SSLHandshake thread
        mStatus err;
        };

mDNSlocal void doTcpSocketCallback(TCPSocket *sock)
        {
        mDNSBool c = !sock->connected;
        sock->connected = mDNStrue;
        sock->callback(sock, sock->context, c, sock->err);
        // Note: the callback may call CloseConnection here, which frees the context structure!
        }

#ifndef NO_SECURITYFRAMEWORK

mDNSlocal OSStatus tlsWriteSock(SSLConnectionRef connection, const void *data, size_t *dataLength)
        {
        int ret = send(((TCPSocket *)connection)->fd, data, *dataLength, 0);
        if (ret >= 0 && (size_t)ret < *dataLength) { *dataLength = ret; return(errSSLWouldBlock); }
        if (ret >= 0)                              { *dataLength = ret; return(noErr); }
        *dataLength = 0;
        if (errno == EAGAIN                      ) return(errSSLWouldBlock);
        if (errno == ENOENT                      ) return(errSSLClosedGraceful);
        if (errno == EPIPE || errno == ECONNRESET) return(errSSLClosedAbort);
        LogMsg("ERROR: tlsWriteSock: %d error %d (%s)\n", ((TCPSocket *)connection)->fd, errno, strerror(errno));
        return(errSSLClosedAbort);
        }

mDNSlocal OSStatus tlsReadSock(SSLConnectionRef connection, void *data, size_t *dataLength)
        {
        int ret = recv(((TCPSocket *)connection)->fd, data, *dataLength, 0);
        if (ret > 0 && (size_t)ret < *dataLength) { *dataLength = ret; return(errSSLWouldBlock); }
        if (ret > 0)                              { *dataLength = ret; return(noErr); }
        *dataLength = 0;
        if (ret == 0 || errno == ENOENT    ) return(errSSLClosedGraceful);
        if (            errno == EAGAIN    ) return(errSSLWouldBlock);
        if (            errno == ECONNRESET) return(errSSLClosedAbort);
        LogMsg("ERROR: tlsSockRead: error %d (%s)\n", errno, strerror(errno));
        return(errSSLClosedAbort);
        }

mDNSlocal OSStatus tlsSetupSock(TCPSocket *sock, mDNSBool server)
        {
        char domname_cstr[MAX_ESCAPED_DOMAIN_NAME];

        mStatus err = SSLNewContext(server, &sock->tlsContext);
        if (err) { LogMsg("ERROR: tlsSetupSock: SSLNewContext failed with error code: %d", err); return(err); }

        err = SSLSetIOFuncs(sock->tlsContext, tlsReadSock, tlsWriteSock);
        if (err) { LogMsg("ERROR: tlsSetupSock: SSLSetIOFuncs failed with error code: %d", err); return(err); }

        err = SSLSetConnection(sock->tlsContext, (SSLConnectionRef) sock);
        if (err) { LogMsg("ERROR: tlsSetupSock: SSLSetConnection failed with error code: %d", err); return(err); }

        // Instead of listing all the acceptable ciphers, we just disable the bad ciphers. It does not disable
        // all the bad ciphers like RC4_MD5, but it assumes that the servers don't offer them.
        err = SSLSetAllowAnonymousCiphers(sock->tlsContext, 0);
        if (err) { LogMsg("ERROR: tlsSetupSock: SSLSetAllowAnonymousCiphers failed with error code: %d", err); return(err); }

        // We already checked for NULL in hostname and this should never happen. Hence, returning -1
        // (error not in OSStatus space) is okay.
        if (!sock->hostname.c[0]) {LogMsg("ERROR: tlsSetupSock: hostname NULL"); return -1; }

        ConvertDomainNameToCString(&sock->hostname, domname_cstr);
        err = SSLSetPeerDomainName(sock->tlsContext, domname_cstr, strlen(domname_cstr));
        if (err) { LogMsg("ERROR: tlsSetupSock: SSLSetPeerDomainname: %s failed with error code: %d", domname_cstr, err); return(err); }

        return(err);
        }

#ifdef __LIB_DISPATCH__
mDNSlocal void doSSLHandshake(void *ctx)
        {
        TCPSocket *sock = (TCPSocket*)ctx;
        mStatus err = SSLHandshake(sock->tlsContext);
        
        //Can't have multiple threads in mDNS core. When __LIB_DISPATCH__ is
        //defined, KQueueLock is a noop. Hence we need to serialize here
        //
        //NOTE: We just can't serialize doTcpSocketCallback alone on the main queue.
        //We need the rest of the logic also. Otherwise, we can enable the READ
        //events below, dispatch a doTcpSocketCallback on the main queue. Assume it is
        //ConnFailed which means we are going to free the tcpInfo. While it
        //is waiting to be dispatched, another read event can come into tcpKQSocketCallback
        //and potentially call doTCPCallback with error which can close the fd and free the
        //tcpInfo. Later when the thread gets dispatched it will crash because the tcpInfo
        //is already freed.

        dispatch_async(dispatch_get_main_queue(), ^{

                LogInfo("doSSLHandshake %p: got lock", sock); // Log *after* we get the lock

                if (sock->handshake == handshake_to_be_closed)
                        {
                        LogInfo("SSLHandshake completed after close");
                        mDNSPlatformTCPCloseConnection(sock);
                        }
                else
                        {
                        if (sock->fd != -1) KQueueSet(sock->fd, EV_ADD, EVFILT_READ, sock->kqEntry);
                        else LogMsg("doSSLHandshake: sock->fd is -1");
        
                        if (err == errSSLWouldBlock)
                                sock->handshake = handshake_required;
                        else
                                {
                                if (err)
                                        {
                                        LogMsg("SSLHandshake failed: %d%s", err, err == errSSLPeerInternalError ? " (server busy)" : "");
                                        SSLDisposeContext(sock->tlsContext);
                                        sock->tlsContext = NULL;
                                        }
                                
                                sock->err = err ? mStatus_ConnFailed : 0;
                                sock->handshake = handshake_completed;
                                
                                LogInfo("doSSLHandshake: %p calling doTcpSocketCallback fd %d", sock, sock->fd);
                                doTcpSocketCallback(sock);
                                }
                        }
        
                LogInfo("SSLHandshake %p: dropping lock for fd %d", sock, sock->fd);
                return;
                });
        }
#else
mDNSlocal void *doSSLHandshake(void *ctx)
        {
        // Warning: Touching sock without the kqueue lock!
        // We're protected because sock->handshake == handshake_in_progress
        TCPSocket *sock = (TCPSocket*)ctx;
        mDNS * const m = sock->m; // Get m now, as we may free sock if marked to be closed while we're waiting on SSLHandshake
        mStatus err = SSLHandshake(sock->tlsContext);
        
        KQueueLock(m);
        debugf("doSSLHandshake %p: got lock", sock); // Log *after* we get the lock

        if (sock->handshake == handshake_to_be_closed)
                {
                LogInfo("SSLHandshake completed after close");
                mDNSPlatformTCPCloseConnection(sock);
                }
        else
                {
                if (sock->fd != -1) KQueueSet(sock->fd, EV_ADD, EVFILT_READ, sock->kqEntry);
                else LogMsg("doSSLHandshake: sock->fd is -1");

                if (err == errSSLWouldBlock)
                        sock->handshake = handshake_required;
                else
                        {
                        if (err)
                                {
                                LogMsg("SSLHandshake failed: %d%s", err, err == errSSLPeerInternalError ? " (server busy)" : "");
                                SSLDisposeContext(sock->tlsContext);
                                sock->tlsContext = NULL;
                                }
                        
                        sock->err = err ? mStatus_ConnFailed : 0;
                        sock->handshake = handshake_completed;
                        
                        debugf("doSSLHandshake: %p calling doTcpSocketCallback fd %d", sock, sock->fd);
                        doTcpSocketCallback(sock);
                        }
                }
        
        debugf("SSLHandshake %p: dropping lock for fd %d", sock, sock->fd);
        KQueueUnlock(m, "doSSLHandshake");
        return NULL;
        }
#endif

mDNSlocal mStatus spawnSSLHandshake(TCPSocket* sock)
        {
        debugf("spawnSSLHandshake %p: entry", sock);
        mStatus err;

        if (sock->handshake != handshake_required) LogMsg("spawnSSLHandshake: handshake status not required: %d", sock->handshake);
        sock->handshake = handshake_in_progress;
        KQueueSet(sock->fd, EV_DELETE, EVFILT_READ, sock->kqEntry);
#ifdef __LIB_DISPATCH__

        // Dispatch it on a separate serial queue to avoid deadlocks with threads running on main queue
        dispatch_async(SSLqueue, ^{doSSLHandshake(sock);});
        err = 0;
#else
        pthread_attr_t attr;
        pthread_attr_init(&attr);
        pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
        err = pthread_create(&sock->handshake_thread, &attr, doSSLHandshake, sock);
        pthread_attr_destroy(&attr);
        if (err)
                {
                LogMsg("Could not start SSLHandshake thread: (%d) %s", err, strerror(err));
                sock->handshake = handshake_completed;
                sock->err = err;
                KQueueSet(sock->fd, EV_ADD, EVFILT_READ, sock->kqEntry);
                }
#endif
        debugf("spawnSSLHandshake %p: done for %d", sock, sock->fd);
        return err;
        }

mDNSlocal mDNSBool IsTunnelModeDomain(const domainname *d)
        {
        static const domainname *mmc = (const domainname*) "\x7" "members" "\x3" "mac" "\x3" "com";
        const domainname *d1 = mDNSNULL;        // TLD
        const domainname *d2 = mDNSNULL;        // SLD
        const domainname *d3 = mDNSNULL;
        while (d->c[0]) { d3 = d2; d2 = d1; d1 = d; d = (const domainname*)(d->c + 1 + d->c[0]); }
        return(d3 && SameDomainName(d3, mmc));
        }

#endif /* NO_SECURITYFRAMEWORK */

mDNSlocal void tcpKQSocketCallback(__unused int fd, short filter, void *context)
        {
        TCPSocket *sock = context;
        sock->err = mStatus_NoError;

        //if (filter == EVFILT_READ ) LogMsg("myKQSocketCallBack: tcpKQSocketCallback %d is EVFILT_READ", filter);
        //if (filter == EVFILT_WRITE) LogMsg("myKQSocketCallBack: tcpKQSocketCallback %d is EVFILT_WRITE", filter);
        // EV_ONESHOT doesn't seem to work, so we add the filter with EV_ADD, and explicitly delete it here with EV_DELETE
        if (filter == EVFILT_WRITE) KQueueSet(sock->fd, EV_DELETE, EVFILT_WRITE, sock->kqEntry);

        if (sock->flags & kTCPSocketFlags_UseTLS)
                {
#ifndef NO_SECURITYFRAMEWORK
                if (!sock->setup) { sock->setup = mDNStrue; tlsSetupSock(sock, mDNSfalse); }
                
                if (sock->handshake == handshake_required) { if (spawnSSLHandshake(sock) == 0) return; }
                else if (sock->handshake == handshake_in_progress || sock->handshake == handshake_to_be_closed) return;
                else if (sock->handshake != handshake_completed)
                        {
                        if (!sock->err) sock->err = mStatus_UnknownErr;
                        LogMsg("tcpKQSocketCallback called with unexpected SSLHandshake status: %d", sock->handshake);
                        }
#else
                sock->err = mStatus_UnsupportedErr;
#endif /* NO_SECURITYFRAMEWORK */
                }
        
        doTcpSocketCallback(sock);
        }

#ifdef __LIB_DISPATCH__
mDNSexport int KQueueSet(int fd, u_short flags, short filter, KQueueEntry *const entryRef)
        {
        dispatch_queue_t queue = dispatch_get_main_queue();
        dispatch_source_t source;
        if (flags == EV_DELETE)
                {
                if (filter == EVFILT_READ)
                        {
                        dispatch_source_cancel(entryRef->readSource);
                        dispatch_release(entryRef->readSource);
                        entryRef->readSource = mDNSNULL;
                        debugf("KQueueSet: source cancel for read %p, %p", entryRef->readSource, entryRef->writeSource);
                        }
                else if (filter == EVFILT_WRITE)
                        {
                        dispatch_source_cancel(entryRef->writeSource);
                        dispatch_release(entryRef->writeSource);
                        entryRef->writeSource = mDNSNULL;
                        debugf("KQueueSet: source cancel for write %p, %p", entryRef->readSource, entryRef->writeSource);
                        }
                else
                        LogMsg("KQueueSet: ERROR: Wrong filter value %d for EV_DELETE", filter);
                return 0;
                }
        if (flags != EV_ADD) LogMsg("KQueueSet: Invalid flags %d", flags);

        if (filter == EVFILT_READ)
                {
                source = dispatch_source_create(DISPATCH_SOURCE_TYPE_READ, fd, 0, queue);
                }
        else if (filter == EVFILT_WRITE)
                {
                source = dispatch_source_create(DISPATCH_SOURCE_TYPE_WRITE, fd, 0, queue);
                }
        else 
                {
                LogMsg("KQueueSet: ERROR: Wrong filter value %d for EV_ADD", filter);
                return -1;
                }
        if (!source) return -1;
        dispatch_source_set_event_handler(source, ^{

                mDNSs32 stime = mDNSPlatformRawTime();
                entryRef->KQcallback(fd, filter, entryRef->KQcontext);
                mDNSs32 etime = mDNSPlatformRawTime();
                if (etime - stime >= WatchDogReportingThreshold)
                        LogInfo("KQEntryCallback Block: WARNING: took %dms to complete", etime - stime);

                // Trigger the event delivery to the application. Even though we trigger the
                // event completion after handling every event source, these all will hopefully
                // get merged
                TriggerEventCompletion();

                });
    dispatch_source_set_cancel_handler(source, ^{
                if (entryRef->fdClosed)
                        {
                        //LogMsg("CancelHandler: closing fd %d", fd);
                        close(fd);
                        }
                });
        dispatch_resume(source);
        if (filter == EVFILT_READ)
                entryRef->readSource = source;
        else
                entryRef->writeSource = source;
                
        return 0;
        }

mDNSexport void KQueueLock(mDNS *const m)
        {
        (void)m; //unused
        }
mDNSexport void KQueueUnlock(mDNS *const m, const char const *task)
        {
        (void)m; //unused
        (void)task; //unused
        }
#else
mDNSexport int KQueueSet(int fd, u_short flags, short filter, const KQueueEntry *const entryRef)
        {
        struct kevent new_event;
        EV_SET(&new_event, fd, filter, flags, 0, 0, (void*)entryRef);
        return (kevent(KQueueFD, &new_event, 1, NULL, 0, NULL) < 0) ? errno : 0;
        }

mDNSexport void KQueueLock(mDNS *const m)
        {
        pthread_mutex_lock(&m->p->BigMutex);
        m->p->BigMutexStartTime = mDNSPlatformRawTime();
        }

mDNSexport void KQueueUnlock(mDNS *const m, const char const *task)
        {
        mDNSs32 end = mDNSPlatformRawTime();
        (void)task;
        if (end - m->p->BigMutexStartTime >= WatchDogReportingThreshold)
                LogInfo("WARNING: %s took %dms to complete", task, end - m->p->BigMutexStartTime);

        pthread_mutex_unlock(&m->p->BigMutex);

        char wake = 1;
        if (send(m->p->WakeKQueueLoopFD, &wake, sizeof(wake), 0) == -1)
                LogMsg("ERROR: KQueueWake: send failed with error code: %d (%s)", errno, strerror(errno));
        }
#endif

mDNSexport void mDNSPlatformCloseFD(KQueueEntry *kq, int fd)
        {
#ifdef __LIB_DISPATCH__
        (void)fd; //unused
        if (kq->readSource)
                {
                dispatch_source_cancel(kq->readSource);
                kq->readSource = mDNSNULL;
                }
        if (kq->writeSource)
                {       
                dispatch_source_cancel(kq->writeSource);
                kq->writeSource = mDNSNULL;
                }
        // Close happens in the cancellation handler
        debugf("mDNSPlatformCloseFD: resetting sources for %d", fd);
        kq->fdClosed = mDNStrue;
#else
        (void)kq; //unused
        close(fd);
#endif
        }

mDNSlocal mStatus SetupTCPSocket(TCPSocket *sock, u_short sa_family, mDNSIPPort *port)
        {
        KQSocketSet *cp = &sock->ss;
#ifndef NO_IPV6
    int         *s        = (sa_family == AF_INET) ? &cp->sktv4 : &cp->sktv6;
    KQueueEntry *k        = (sa_family == AF_INET) ? &cp->kqsv4 : &cp->kqsv6;
#else
    int         *s        = &cp->sktv4;
    KQueueEntry *k        = &cp->kqsv4;
#endif
        const int on = 1;  // "on" for setsockopt
        mStatus err;

    int skt = socket(sa_family, SOCK_STREAM, IPPROTO_TCP);
    if (skt < 3) { if (errno != EAFNOSUPPORT) LogMsg("SetupTCPSocket: socket error %d errno %d (%s)", skt, errno, strerror(errno)); return(skt); }
        if (sa_family == AF_INET)
                {
                // Bind it
                struct sockaddr_in addr;
                mDNSPlatformMemZero(&addr, sizeof(addr));
                addr.sin_family = AF_INET;
                addr.sin_port = port->NotAnInteger;
                err = bind(skt, (struct sockaddr*) &addr, sizeof(addr));
                if (err < 0) { LogMsg("ERROR: bind %s", strerror(errno)); return err; }
        
                // Receive interface identifiers
                err = setsockopt(skt, IPPROTO_IP, IP_RECVIF, &on, sizeof(on));
                if (err < 0) { LogMsg("setsockopt IP_RECVIF - %s", strerror(errno)); return err; }
        
                mDNSPlatformMemZero(&addr, sizeof(addr));
                socklen_t len = sizeof(addr);
                err = getsockname(skt, (struct sockaddr*) &addr, &len);
                if (err < 0) { LogMsg("getsockname - %s", strerror(errno)); return err; }
        
                port->NotAnInteger = addr.sin_port;
                }
        else
                {
                // Bind it
                struct sockaddr_in6 addr6;
                mDNSPlatformMemZero(&addr6, sizeof(addr6));
                addr6.sin6_family = AF_INET6;
                addr6.sin6_port = port->NotAnInteger;
                err = bind(skt, (struct sockaddr*) &addr6, sizeof(addr6));
                if (err < 0) { LogMsg("ERROR: bind6 %s", strerror(errno)); return err; }

                // We want to receive destination addresses and receive interface identifiers
        err = setsockopt(skt, IPPROTO_IPV6, IPV6_PKTINFO, &on, sizeof(on));
                if (err < 0) { LogMsg("ERROR: setsockopt IPV6_PKTINFO %s", strerror(errno)); return err; }

                mDNSPlatformMemZero(&addr6, sizeof(addr6));
                socklen_t len = sizeof(addr6);
                err = getsockname(skt, (struct sockaddr *) &addr6, &len);
                if (err < 0) { LogMsg("getsockname6 - %s", strerror(errno)); return err; }
        
                port->NotAnInteger = addr6.sin6_port;

                }
        *s = skt;
        k->KQcallback = tcpKQSocketCallback;
        k->KQcontext  = sock;
        k->KQtask     = "mDNSPlatformTCPSocket";
#ifdef __LIB_DISPATCH__
        k->readSource = mDNSNULL;
        k->writeSource = mDNSNULL;
        k->fdClosed = mDNSfalse;
#endif
        return mStatus_NoError;
        }

mDNSexport TCPSocket *mDNSPlatformTCPSocket(mDNS *const m, TCPSocketFlags flags, mDNSIPPort *port)
        {
        mStatus err;
        (void) m;

        TCPSocket *sock = mallocL("TCPSocket/mDNSPlatformTCPSocket", sizeof(TCPSocket));
        if (!sock) { LogMsg("mDNSPlatformTCPSocket: memory allocation failure"); return(mDNSNULL); }

        mDNSPlatformMemZero(sock, sizeof(TCPSocket));

        sock->ss.m     = m;
        sock->ss.sktv4 = -1;
#ifndef NO_IPV6
        sock->ss.sktv6 = -1;
#endif
        err = SetupTCPSocket(sock, AF_INET, port);
#ifndef NO_IPV6
        if (!err)
                {
                err = SetupTCPSocket(sock, AF_INET6, port);
                if (err) { mDNSPlatformCloseFD(&sock->ss.kqsv4, sock->ss.sktv4); sock->ss.sktv4 = -1; }
                }
#endif
        if (err)
                {
                LogMsg("mDNSPlatformTCPSocket: socket error %d errno %d (%s)", sock->fd, errno, strerror(errno));
                freeL("TCPSocket/mDNSPlatformTCPSocket", sock);
                return(mDNSNULL);
                }

        sock->callback          = mDNSNULL;
        sock->flags             = flags;
        sock->context           = mDNSNULL;
        sock->setup             = mDNSfalse;
        sock->connected         = mDNSfalse;
        sock->handshake         = handshake_required;
        sock->m                 = m;
        sock->err               = mStatus_NoError;
        
        return sock;
        }

mDNSexport mStatus mDNSPlatformTCPConnect(TCPSocket *sock, const mDNSAddr *dst, mDNSOpaque16 dstport, domainname *hostname, mDNSInterfaceID InterfaceID, TCPConnectionCallback callback, void *context)
        {
        KQSocketSet *cp = &sock->ss;
#ifndef NO_IPV6
    int         *s        = (dst->type == mDNSAddrType_IPv4) ? &cp->sktv4 : &cp->sktv6;
    KQueueEntry *k        = (dst->type == mDNSAddrType_IPv4) ? &cp->kqsv4 : &cp->kqsv6;
#else
    int         *s        = &cp->sktv4;
    KQueueEntry *k        = &cp->kqsv4;
#endif
        mStatus err = mStatus_NoError;
        struct sockaddr_storage ss;

        sock->callback          = callback;
        sock->context           = context;
        sock->setup             = mDNSfalse;
        sock->connected         = mDNSfalse;
        sock->handshake         = handshake_required;
        sock->err               = mStatus_NoError;

        if (hostname) { debugf("mDNSPlatformTCPConnect: hostname %##s", hostname->c); AssignDomainName(&sock->hostname, hostname); }

        if (dst->type == mDNSAddrType_IPv4)
                {
                struct sockaddr_in *saddr = (struct sockaddr_in *)&ss;
                mDNSPlatformMemZero(saddr, sizeof(*saddr));
                saddr->sin_family      = AF_INET;
                saddr->sin_port        = dstport.NotAnInteger;
                saddr->sin_len         = sizeof(*saddr);
                saddr->sin_addr.s_addr = dst->ip.v4.NotAnInteger;
                }
        else
                {
                struct sockaddr_in6 *saddr6 = (struct sockaddr_in6 *)&ss;
                mDNSPlatformMemZero(saddr6, sizeof(*saddr6));
                saddr6->sin6_family      = AF_INET6;
                saddr6->sin6_port        = dstport.NotAnInteger;
                saddr6->sin6_len         = sizeof(*saddr6);
                saddr6->sin6_addr        = *(struct in6_addr *)&dst->ip.v6;
                }

        // Watch for connect complete (write is ready)
        // EV_ONESHOT doesn't seem to work, so we add the filter with EV_ADD, and explicitly delete it in tcpKQSocketCallback using EV_DELETE
        if (KQueueSet(*s, EV_ADD /* | EV_ONESHOT */, EVFILT_WRITE, k))
                {
                LogMsg("ERROR: mDNSPlatformTCPConnect - KQueueSet failed");
                return errno;
                }

        // Watch for incoming data
        if (KQueueSet(*s, EV_ADD, EVFILT_READ, k))
                {
                LogMsg("ERROR: mDNSPlatformTCPConnect - KQueueSet failed");
                return errno;
                }

        if (fcntl(*s, F_SETFL, fcntl(*s, F_GETFL, 0) | O_NONBLOCK) < 0) // set non-blocking
                {
                LogMsg("ERROR: setsockopt O_NONBLOCK - %s", strerror(errno));
                return mStatus_UnknownErr;
                }

        // We bind to the interface and all subsequent packets including the SYN will be sent out
        // on this interface
        //
        // Note: If we are in Active Directory domain, we may try TCP (if the response can't fit in
        // UDP). mDNSInterface_Unicast indicates this case and not a valid interface.
        if (InterfaceID && InterfaceID != mDNSInterface_Unicast)
                {
                extern mDNS mDNSStorage;
                NetworkInterfaceInfoOSX *info = IfindexToInterfaceInfoOSX(&mDNSStorage, InterfaceID);
                if (dst->type == mDNSAddrType_IPv4)
                        {
                #ifdef IP_BOUND_IF
                        if (info) setsockopt(*s, IPPROTO_IP, IP_BOUND_IF, &info->scope_id, sizeof(info->scope_id));
                        else { LogMsg("mDNSPlatformTCPConnect: Invalid interface index %p", InterfaceID); return mStatus_BadParamErr; }
                #else
                        (void)InterfaceID; // Unused
                        (void)info; // Unused
                #endif
                        }
                else
                        {
                #ifdef IPV6_BOUND_IF
                        if (info) setsockopt(*s, IPPROTO_IPV6, IPV6_BOUND_IF, &info->scope_id, sizeof(info->scope_id));
                        else { LogMsg("mDNSPlatformTCPConnect: Invalid interface index %p", InterfaceID); return mStatus_BadParamErr; }
                #else
                        (void)InterfaceID; // Unused
                        (void)info; // Unused
                #endif
                        }
                }

        // mDNSPlatformReadTCP/WriteTCP (unlike the UDP counterpart) does not provide the destination address
        // from which we can infer the destination address family. Hence we need to remember that here.
        // Instead of remembering the address family, we remember the right fd.
        sock->fd = *s;
        sock->kqEntry = k;
        // initiate connection wth peer
        if (connect(*s, (struct sockaddr *)&ss, ss.ss_len) < 0)
                {
                if (errno == EINPROGRESS) return mStatus_ConnPending;
                if (errno == EHOSTUNREACH || errno == EADDRNOTAVAIL || errno == ENETDOWN)
                        LogInfo("ERROR: mDNSPlatformTCPConnect - connect failed: socket %d: Error %d (%s)", sock->fd, errno, strerror(errno));
                else
                        LogMsg("ERROR: mDNSPlatformTCPConnect - connect failed: socket %d: Error %d (%s) length %d", sock->fd, errno, strerror(errno), ss.ss_len);
                return mStatus_ConnFailed;
                }

        LogMsg("NOTE: mDNSPlatformTCPConnect completed synchronously");
        // kQueue should notify us, but this LogMsg is to help track down if it doesn't
        return err;
        }

// Why doesn't mDNSPlatformTCPAccept actually call accept() ?
mDNSexport TCPSocket *mDNSPlatformTCPAccept(TCPSocketFlags flags, int fd)
        {
        mStatus err = mStatus_NoError;

        TCPSocket *sock = mallocL("TCPSocket/mDNSPlatformTCPAccept", sizeof(TCPSocket));
        if (!sock) return(mDNSNULL);

        mDNSPlatformMemZero(sock, sizeof(*sock));
        sock->fd = fd;
        sock->flags = flags;

        if (flags & kTCPSocketFlags_UseTLS)
                {
#ifndef NO_SECURITYFRAMEWORK
                if (!ServerCerts) { LogMsg("ERROR: mDNSPlatformTCPAccept: unable to find TLS certificates"); err = mStatus_UnknownErr; goto exit; }

                err = tlsSetupSock(sock, mDNStrue);
                if (err) { LogMsg("ERROR: mDNSPlatformTCPAccept: tlsSetupSock failed with error code: %d", err); goto exit; }

                err = SSLSetCertificate(sock->tlsContext, ServerCerts);
                if (err) { LogMsg("ERROR: mDNSPlatformTCPAccept: SSLSetCertificate failed with error code: %d", err); goto exit; }
#else
                err = mStatus_UnsupportedErr;
#endif /* NO_SECURITYFRAMEWORK */
                }
#ifndef NO_SECURITYFRAMEWORK
exit:
#endif

        if (err) { freeL("TCPSocket/mDNSPlatformTCPAccept", sock); return(mDNSNULL); }
        return(sock);
        }

mDNSlocal void CloseSocketSet(KQSocketSet *ss)
        {
        if (ss->sktv4 != -1)
                {
                mDNSPlatformCloseFD(&ss->kqsv4,  ss->sktv4);
                ss->sktv4 = -1;
                }
#ifndef NO_IPV6
        if (ss->sktv6 != -1)
                {
                mDNSPlatformCloseFD(&ss->kqsv6,  ss->sktv6);
                ss->sktv6 = -1;
                }
#endif
        if (ss->closeFlag) *ss->closeFlag = 1;
        }

mDNSexport void mDNSPlatformTCPCloseConnection(TCPSocket *sock)
        {
        if (sock)
                {       
#ifndef NO_SECURITYFRAMEWORK
                if (sock->tlsContext)
                        {
                        if (sock->handshake == handshake_in_progress) // SSLHandshake thread using this sock (esp. tlsContext)
                                {
                                LogInfo("mDNSPlatformTCPCloseConnection: called while handshake in progress");
                                sock->handshake = handshake_to_be_closed;
                                }
                        if (sock->handshake == handshake_to_be_closed)
                                return;

                        SSLClose(sock->tlsContext);
                        SSLDisposeContext(sock->tlsContext);
                        sock->tlsContext = NULL;
                        }
#endif /* NO_SECURITYFRAMEWORK */
                        if (sock->ss.sktv4 != -1) shutdown(sock->ss.sktv4, 2);
#ifndef NO_IPV6
                        if (sock->ss.sktv6 != -1) shutdown(sock->ss.sktv6, 2);
#endif
                        CloseSocketSet(&sock->ss);
                        sock->fd = -1;

                freeL("TCPSocket/mDNSPlatformTCPCloseConnection", sock);
                }
        }

mDNSexport long mDNSPlatformReadTCP(TCPSocket *sock, void *buf, unsigned long buflen, mDNSBool *closed)
        {
        size_t nread = 0;
        *closed = mDNSfalse;

        if (sock->flags & kTCPSocketFlags_UseTLS)
                {
#ifndef NO_SECURITYFRAMEWORK
                if (sock->handshake == handshake_required) { LogMsg("mDNSPlatformReadTCP called while handshake required"); return 0; }
                else if (sock->handshake == handshake_in_progress) return 0;
                else if (sock->handshake != handshake_completed) LogMsg("mDNSPlatformReadTCP called with unexpected SSLHandshake status: %d", sock->handshake);

                //LogMsg("Starting SSLRead %d %X", sock->fd, fcntl(sock->fd, F_GETFL, 0));
                mStatus err = SSLRead(sock->tlsContext, buf, buflen, &nread);
                //LogMsg("SSLRead returned %d (%d) nread %d buflen %d", err, errSSLWouldBlock, nread, buflen);
                if (err == errSSLClosedGraceful) { nread = 0; *closed = mDNStrue; }
                else if (err && err != errSSLWouldBlock)
                        { LogMsg("ERROR: mDNSPlatformReadTCP - SSLRead: %d", err); nread = -1; *closed = mDNStrue; }
#else
                nread = -1;
                *closed = mDNStrue;
#endif /* NO_SECURITYFRAMEWORK */
                }
        else
                {
                static int CLOSEDcount = 0;
                static int EAGAINcount = 0;
                nread = recv(sock->fd, buf, buflen, 0);

                if (nread > 0) { CLOSEDcount = 0; EAGAINcount = 0; } // On success, clear our error counters
                else if (nread == 0)
                        {
                        *closed = mDNStrue;
                        if ((++CLOSEDcount % 1000) == 0) { LogMsg("ERROR: mDNSPlatformReadTCP - recv %d got CLOSED %d times", sock->fd, CLOSEDcount); sleep(1); }
                        }
                // else nread is negative -- see what kind of error we got
                else if (errno == ECONNRESET) { nread = 0; *closed = mDNStrue; }
                else if (errno != EAGAIN) { LogMsg("ERROR: mDNSPlatformReadTCP - recv: %d (%s)", errno, strerror(errno)); nread = -1; }
                else // errno is EAGAIN (EWOULDBLOCK) -- no data available
                        {
                        nread = 0;
                        if ((++EAGAINcount % 1000) == 0) { LogMsg("ERROR: mDNSPlatformReadTCP - recv %d got EAGAIN %d times", sock->fd, EAGAINcount); sleep(1); }
                        }
                }

        return nread;
        }

mDNSexport long mDNSPlatformWriteTCP(TCPSocket *sock, const char *msg, unsigned long len)
        {
        int nsent;

        if (sock->flags & kTCPSocketFlags_UseTLS)
                {
#ifndef NO_SECURITYFRAMEWORK
                size_t  processed;
                if (sock->handshake == handshake_required) { LogMsg("mDNSPlatformWriteTCP called while handshake required"); return 0; }
                if (sock->handshake == handshake_in_progress) return 0;
                else if (sock->handshake != handshake_completed) LogMsg("mDNSPlatformWriteTCP called with unexpected SSLHandshake status: %d", sock->handshake);
                
                mStatus err = SSLWrite(sock->tlsContext, msg, len, &processed);

                if (!err) nsent = (int) processed;
                else if (err == errSSLWouldBlock) nsent = 0;
                else { LogMsg("ERROR: mDNSPlatformWriteTCP - SSLWrite returned %d", err); nsent = -1; }
#else
                nsent = -1;
#endif /* NO_SECURITYFRAMEWORK */
                }
        else
                {
                nsent = send(sock->fd, msg, len, 0);
                if (nsent < 0)
                        {
                        if (errno == EAGAIN) nsent = 0;
                        else { LogMsg("ERROR: mDNSPlatformWriteTCP - send %s", strerror(errno)); nsent = -1; }
                        }
                }

        return nsent;
        }

mDNSexport int mDNSPlatformTCPGetFD(TCPSocket *sock)
        {
        return sock->fd;
        }

// If mDNSIPPort port is non-zero, then it's a multicast socket on the specified interface
// If mDNSIPPort port is zero, then it's a randomly assigned port number, used for sending unicast queries
mDNSlocal mStatus SetupSocket(KQSocketSet *cp, const mDNSIPPort port, u_short sa_family, mDNSIPPort *const outport)
        {
#ifndef NO_IPV6
        int         *s        = (sa_family == AF_INET) ? &cp->sktv4 : &cp->sktv6;
        KQueueEntry     *k        = (sa_family == AF_INET) ? &cp->kqsv4 : &cp->kqsv6;
#else
        int         *s        = &cp->sktv4;
        KQueueEntry     *k        = &cp->kqsv4;
#endif
        const int on = 1;
        const int twofivefive = 255;
        mStatus err = mStatus_NoError;
        char *errstr = mDNSNULL;

#ifdef NO_IPV6
        if (sa_family != AF_INET) return -1;
#endif
        
        cp->closeFlag = mDNSNULL;

        int skt = socket(sa_family, SOCK_DGRAM, IPPROTO_UDP);
        if (skt < 3) { if (errno != EAFNOSUPPORT) LogMsg("SetupSocket: socket error %d errno %d (%s)", skt, errno, strerror(errno)); return(skt); }

        // ... with a shared UDP port, if it's for multicast receiving
        if (mDNSSameIPPort(port, MulticastDNSPort) || mDNSSameIPPort(port, NATPMPAnnouncementPort)) err = setsockopt(skt, SOL_SOCKET, SO_REUSEPORT, &on, sizeof(on));
        if (err < 0) { errstr = "setsockopt - SO_REUSEPORT"; goto fail; }

        if (sa_family == AF_INET)
                {
                // We want to receive destination addresses
                err = setsockopt(skt, IPPROTO_IP, IP_RECVDSTADDR, &on, sizeof(on));
                if (err < 0) { errstr = "setsockopt - IP_RECVDSTADDR"; goto fail; }

                // We want to receive interface identifiers
                err = setsockopt(skt, IPPROTO_IP, IP_RECVIF, &on, sizeof(on));
                if (err < 0) { errstr = "setsockopt - IP_RECVIF"; goto fail; }

                // We want to receive packet TTL value so we can check it
                err = setsockopt(skt, IPPROTO_IP, IP_RECVTTL, &on, sizeof(on));
                // We ignore errors here -- we already know Jaguar doesn't support this, but we can get by without it

                // Send unicast packets with TTL 255
                err = setsockopt(skt, IPPROTO_IP, IP_TTL, &twofivefive, sizeof(twofivefive));
                if (err < 0) { errstr = "setsockopt - IP_TTL"; goto fail; }

                // And multicast packets with TTL 255 too
                err = setsockopt(skt, IPPROTO_IP, IP_MULTICAST_TTL, &twofivefive, sizeof(twofivefive));
                if (err < 0) { errstr = "setsockopt - IP_MULTICAST_TTL"; goto fail; }

                // And start listening for packets
                struct sockaddr_in listening_sockaddr;
                listening_sockaddr.sin_family      = AF_INET;
                listening_sockaddr.sin_port        = port.NotAnInteger;         // Pass in opaque ID without any byte swapping
                listening_sockaddr.sin_addr.s_addr = mDNSSameIPPort(port, NATPMPAnnouncementPort) ? AllHosts_v4.NotAnInteger : 0;
                err = bind(skt, (struct sockaddr *) &listening_sockaddr, sizeof(listening_sockaddr));
                if (err) { errstr = "bind"; goto fail; }
                if (outport) outport->NotAnInteger = listening_sockaddr.sin_port;
                }
#ifndef NO_IPV6
        else if (sa_family == AF_INET6)
                {
                // NAT-PMP Announcements make no sense on IPv6, so bail early w/o error
                if (mDNSSameIPPort(port, NATPMPAnnouncementPort)) { if (outport) *outport = zeroIPPort; return mStatus_NoError; }
                
                // We want to receive destination addresses and receive interface identifiers
                err = setsockopt(skt, IPPROTO_IPV6, IPV6_PKTINFO, &on, sizeof(on));
                if (err < 0) { errstr = "setsockopt - IPV6_PKTINFO"; goto fail; }

                // We want to receive packet hop count value so we can check it
                err = setsockopt(skt, IPPROTO_IPV6, IPV6_HOPLIMIT, &on, sizeof(on));
                if (err < 0) { errstr = "setsockopt - IPV6_HOPLIMIT"; goto fail; }

                // We want to receive only IPv6 packets. Without this option we get IPv4 packets too,
                // with mapped addresses of the form 0:0:0:0:0:FFFF:xxxx:xxxx, where xxxx:xxxx is the IPv4 address
                err = setsockopt(skt, IPPROTO_IPV6, IPV6_V6ONLY, &on, sizeof(on));
                if (err < 0) { errstr = "setsockopt - IPV6_V6ONLY"; goto fail; }

                // Send unicast packets with TTL 255
                err = setsockopt(skt, IPPROTO_IPV6, IPV6_UNICAST_HOPS, &twofivefive, sizeof(twofivefive));
                if (err < 0) { errstr = "setsockopt - IPV6_UNICAST_HOPS"; goto fail; }

                // And multicast packets with TTL 255 too
                err = setsockopt(skt, IPPROTO_IPV6, IPV6_MULTICAST_HOPS, &twofivefive, sizeof(twofivefive));
                if (err < 0) { errstr = "setsockopt - IPV6_MULTICAST_HOPS"; goto fail; }

                // Want to receive our own packets
                err = setsockopt(skt, IPPROTO_IPV6, IPV6_MULTICAST_LOOP, &on, sizeof(on));
                if (err < 0) { errstr = "setsockopt - IPV6_MULTICAST_LOOP"; goto fail; }

                // And start listening for packets
                struct sockaddr_in6 listening_sockaddr6;
                mDNSPlatformMemZero(&listening_sockaddr6, sizeof(listening_sockaddr6));
                listening_sockaddr6.sin6_len         = sizeof(listening_sockaddr6);
                listening_sockaddr6.sin6_family      = AF_INET6;
                listening_sockaddr6.sin6_port        = port.NotAnInteger;               // Pass in opaque ID without any byte swapping
                listening_sockaddr6.sin6_flowinfo    = 0;
                listening_sockaddr6.sin6_addr        = in6addr_any; // Want to receive multicasts AND unicasts on this socket
                listening_sockaddr6.sin6_scope_id    = 0;
                err = bind(skt, (struct sockaddr *) &listening_sockaddr6, sizeof(listening_sockaddr6));
                if (err) { errstr = "bind"; goto fail; }
                if (outport) outport->NotAnInteger = listening_sockaddr6.sin6_port;
                }
#endif

        fcntl(skt, F_SETFL, fcntl(skt, F_GETFL, 0) | O_NONBLOCK); // set non-blocking
        fcntl(skt, F_SETFD, 1); // set close-on-exec
        *s = skt;
        k->KQcallback = myKQSocketCallBack;
        k->KQcontext  = cp;
        k->KQtask     = "UDP packet reception";
#ifdef __LIB_DISPATCH__
        k->readSource = mDNSNULL;
        k->writeSource = mDNSNULL;
        k->fdClosed = mDNSfalse;
#endif
        KQueueSet(*s, EV_ADD, EVFILT_READ, k);

        return(err);

        fail:
        // For "bind" failures, only write log messages for our shared mDNS port, or for binding to zero
        if (strcmp(errstr, "bind") || mDNSSameIPPort(port, MulticastDNSPort) || mDNSIPPortIsZero(port))
                LogMsg("%s skt %d port %d error %d errno %d (%s)", errstr, skt, mDNSVal16(port), err, errno, strerror(errno));

        // If we got a "bind" failure of EADDRINUSE, inform the caller as it might need to try another random port
        if (!strcmp(errstr, "bind") && errno == EADDRINUSE)
                {
                err = EADDRINUSE;
                if (mDNSSameIPPort(port, MulticastDNSPort))
                        NotifyOfElusiveBug("Setsockopt SO_REUSEPORT failed",
                                "Congratulations, you've reproduced an elusive bug.\r"
                                "Please contact the current assignee of <rdar://problem/3814904>.\r"
                                "Alternatively, you can send email to radar-3387020@group.apple.com. (Note number is different.)\r"
                                "If possible, please leave your machine undisturbed so that someone can come to investigate the problem.");
                }

        mDNSPlatformCloseFD(k, skt);
        return(err);
        }

mDNSexport UDPSocket *mDNSPlatformUDPSocket(mDNS *const m, const mDNSIPPort requestedport)
        {
        mStatus err;
        mDNSIPPort port = requestedport;
        mDNSBool randomizePort = mDNSIPPortIsZero(requestedport);
        int i = 10000; // Try at most 10000 times to get a unique random port
        UDPSocket *p = mallocL("UDPSocket", sizeof(UDPSocket));
        if (!p) { LogMsg("mDNSPlatformUDPSocket: memory exhausted"); return(mDNSNULL); }
        mDNSPlatformMemZero(p, sizeof(UDPSocket));
        p->ss.port  = zeroIPPort;
        p->ss.m     = m;
        p->ss.sktv4 = -1;
#ifndef NO_IPV6
        p->ss.sktv6 = -1;
#endif

        do
                {
                // The kernel doesn't do cryptographically strong random port allocation, so we do it ourselves here
                if (randomizePort) port = mDNSOpaque16fromIntVal(0xC000 + mDNSRandom(0x3FFF));
                err = SetupSocket(&p->ss, port, AF_INET, &p->ss.port);
#ifndef NO_IPV6
                if (!err)
                        {
                        err = SetupSocket(&p->ss, port, AF_INET6, &p->ss.port);
                        if (err) { mDNSPlatformCloseFD(&p->ss.kqsv4, p->ss.sktv4); p->ss.sktv4 = -1; }
                        }
#endif
                i--;
                } while (err == EADDRINUSE && randomizePort && i);

        if (err)
                {
                // In customer builds we don't want to log failures with port 5351, because this is a known issue
                // of failing to bind to this port when Internet Sharing has already bound to it
                // We also don't want to log about port 5350, due to a known bug when some other
                // process is bound to it.
                if (mDNSSameIPPort(requestedport, NATPMPPort) || mDNSSameIPPort(requestedport, NATPMPAnnouncementPort))
                        LogInfo("mDNSPlatformUDPSocket: SetupSocket %d failed error %d errno %d (%s)", mDNSVal16(requestedport), err, errno, strerror(errno));
                else LogMsg("mDNSPlatformUDPSocket: SetupSocket %d failed error %d errno %d (%s)", mDNSVal16(requestedport), err, errno, strerror(errno));
                freeL("UDPSocket", p);
                return(mDNSNULL);
                }
        return(p);
        }

mDNSexport void mDNSPlatformUDPClose(UDPSocket *sock)
        {
        CloseSocketSet(&sock->ss);
        freeL("UDPSocket", sock);
        }

#if COMPILER_LIKES_PRAGMA_MARK
#pragma mark -
#pragma mark - BPF Raw packet sending/receiving
#endif

#if APPLE_OSX_mDNSResponder

mDNSexport void mDNSPlatformSendRawPacket(const void *const msg, const mDNSu8 *const end, mDNSInterfaceID InterfaceID)
        {
        if (!InterfaceID) { LogMsg("mDNSPlatformSendRawPacket: No InterfaceID specified"); return; }
        NetworkInterfaceInfoOSX *info;

        extern mDNS mDNSStorage;
        info = IfindexToInterfaceInfoOSX(&mDNSStorage, InterfaceID);
        if (info == NULL)
                {
                LogMsg("mDNSPlatformSendUDP: Invalid interface index %p", InterfaceID);
                return;
                }
        if (info->BPF_fd < 0)
                LogMsg("mDNSPlatformSendRawPacket: %s BPF_fd %d not ready", info->ifinfo.ifname, info->BPF_fd);
        else
                {
                //LogMsg("mDNSPlatformSendRawPacket %d bytes on %s", end - (mDNSu8 *)msg, info->ifinfo.ifname);
                if (write(info->BPF_fd, msg, end - (mDNSu8 *)msg) < 0)
                        LogMsg("mDNSPlatformSendRawPacket: BPF write(%d) failed %d (%s)", info->BPF_fd, errno, strerror(errno));
                }
        }

mDNSexport void mDNSPlatformSetLocalAddressCacheEntry(mDNS *const m, const mDNSAddr *const tpa, const mDNSEthAddr *const tha, mDNSInterfaceID InterfaceID)
        {
        if (!InterfaceID) { LogMsg("mDNSPlatformSetLocalAddressCacheEntry: No InterfaceID specified"); return; }
        NetworkInterfaceInfoOSX *info;
        info = IfindexToInterfaceInfoOSX(m, InterfaceID);
        if (info == NULL) { LogMsg("mDNSPlatformSetLocalAddressCacheEntry: Invalid interface index %p", InterfaceID); return; }
        // Manually inject an entry into our local ARP cache.
        // (We can't do this by sending an ARP broadcast, because the kernel only pays attention to incoming ARP packets, not outgoing.)
        if (!mDNS_AddressIsLocalSubnet(m, InterfaceID, tpa))
                LogSPS("Don't need address cache entry for %s %#a %.6a",            info->ifinfo.ifname, tpa, tha);
        else
                {
                int result = mDNSSetLocalAddressCacheEntry(info->scope_id, tpa->type, tpa->ip.v6.b, tha->b);
                if (result) LogMsg("Set local address cache entry for %s %#a %.6a failed: %d", info->ifinfo.ifname, tpa, tha, result);
                else        LogSPS("Set local address cache entry for %s %#a %.6a",            info->ifinfo.ifname, tpa, tha);
                }
        }

mDNSlocal void CloseBPF(NetworkInterfaceInfoOSX *const i)
        {
        LogSPS("%s closing BPF fd %d", i->ifinfo.ifname, i->BPF_fd);
#ifdef __LIB_DISPATCH__
        // close will happen in the cancel handler
        dispatch_source_cancel(i->BPF_source);
#else

        // Note: MUST NOT close() the underlying native BSD sockets.
        // CFSocketInvalidate() will do that for us, in its own good time, which may not necessarily be immediately, because
        // it first has to unhook the sockets from its select() call on its other thread, before it can safely close them.
        CFRunLoopRemoveSource(i->m->p->CFRunLoop, i->BPF_rls, kCFRunLoopDefaultMode);
        CFRelease(i->BPF_rls);
        CFSocketInvalidate(i->BPF_cfs);
        CFRelease(i->BPF_cfs);
#endif
        i->BPF_fd = -1;
        if (i->BPF_mcfd >= 0) { close(i->BPF_mcfd); i->BPF_mcfd = -1; }
        }

mDNSlocal void bpf_callback_common(NetworkInterfaceInfoOSX *info)
        {
        KQueueLock(info->m);

        // Now we've got the lock, make sure the kqueue thread didn't close the fd out from under us (will not be a problem once the OS X
        // kernel has a mechanism for dispatching all events to a single thread, but for now we have to guard against this race condition).
        if (info->BPF_fd < 0) goto exit;

        ssize_t n = read(info->BPF_fd, &info->m->imsg, info->BPF_len);
        const mDNSu8 *ptr = (const mDNSu8 *)&info->m->imsg;
        const mDNSu8 *end = (const mDNSu8 *)&info->m->imsg + n;
        debugf("%3d: bpf_callback got %d bytes on %s", info->BPF_fd, n, info->ifinfo.ifname);

        if (n<0)
                {
                LogMsg("Closing %s BPF fd %d due to error %d (%s)", info->ifinfo.ifname, info->BPF_fd, errno, strerror(errno));
                CloseBPF(info);
                goto exit;
                }

        while (ptr < end)
                {
                const struct bpf_hdr *const bh = (const struct bpf_hdr *)ptr;
                debugf("%3d: bpf_callback ptr %p bh_hdrlen %d data %p bh_caplen %4d bh_datalen %4d next %p remaining %4d",
                        info->BPF_fd, ptr, bh->bh_hdrlen, ptr + bh->bh_hdrlen, bh->bh_caplen, bh->bh_datalen,
                        ptr + BPF_WORDALIGN(bh->bh_hdrlen + bh->bh_caplen), end - (ptr + BPF_WORDALIGN(bh->bh_hdrlen + bh->bh_caplen)));
                // Note that BPF guarantees that the NETWORK LAYER header will be word aligned, not the link-layer header.
                // Given that An Ethernet header is 14 bytes, this means that if the network layer header (e.g. IP header,
                // ARP message, etc.) is 4-byte aligned, then necessarily the Ethernet header will be NOT be 4-byte aligned.
                mDNSCoreReceiveRawPacket(info->m, ptr + bh->bh_hdrlen, ptr + bh->bh_hdrlen + bh->bh_caplen, info->ifinfo.InterfaceID);
                ptr += BPF_WORDALIGN(bh->bh_hdrlen + bh->bh_caplen);
                }
exit:
        KQueueUnlock(info->m, "bpf_callback");
        }
#ifdef __LIB_DISPATCH__
mDNSlocal void bpf_callback_dispatch(NetworkInterfaceInfoOSX *const info)
        {
        bpf_callback_common(info);
        }
#else
mDNSlocal void bpf_callback(const CFSocketRef cfs, const CFSocketCallBackType CallBackType, const CFDataRef address, const void *const data, void *const context)
        {
        (void)cfs;
        (void)CallBackType;
        (void)address;
        (void)data;
        bpf_callback_common((NetworkInterfaceInfoOSX *)context);
        }
#endif

#define BPF_SetOffset(from, cond, to) (from)->cond = (to) - 1 - (from)

mDNSlocal int CountProxyTargets(mDNS *const m, NetworkInterfaceInfoOSX *x, int *p4, int *p6)
        {
        int numv4 = 0, numv6 = 0;
        AuthRecord *rr;

        for (rr = m->ResourceRecords; rr; rr=rr->next)
                if (rr->resrec.InterfaceID == x->ifinfo.InterfaceID && rr->AddressProxy.type == mDNSAddrType_IPv4)
                        {
                        if (p4) LogSPS("CountProxyTargets: fd %d %-7s IP%2d %.4a", x->BPF_fd, x->ifinfo.ifname, numv4, &rr->AddressProxy.ip.v4);
                        numv4++;
                        }

        for (rr = m->ResourceRecords; rr; rr=rr->next)
                if (rr->resrec.InterfaceID == x->ifinfo.InterfaceID && rr->AddressProxy.type == mDNSAddrType_IPv6)
                        {
                        if (p6) LogSPS("CountProxyTargets: fd %d %-7s IP%2d %.16a", x->BPF_fd, x->ifinfo.ifname, numv6, &rr->AddressProxy.ip.v6);
                        numv6++;
                        }

        if (p4) *p4 = numv4;
        if (p6) *p6 = numv6;
        return(numv4 + numv6);
        }

mDNSexport void mDNSPlatformUpdateProxyList(mDNS *const m, const mDNSInterfaceID InterfaceID)
        {
        NetworkInterfaceInfoOSX *x;

        // Note: We can't use IfIndexToInterfaceInfoOSX because that looks for Registered also.
        for (x = m->p->InterfaceList; x; x = x->next) if (x->ifinfo.InterfaceID == InterfaceID) break;

        if (!x) { LogMsg("mDNSPlatformUpdateProxyList: ERROR InterfaceID %p not found", InterfaceID); return; }

        #define MAX_BPF_ADDRS 250
        int numv4 = 0, numv6 = 0;

        if (CountProxyTargets(m, x, &numv4, &numv6) > MAX_BPF_ADDRS)
                {
                LogMsg("mDNSPlatformUpdateProxyList: ERROR Too many address proxy records v4 %d v6 %d", numv4, numv6);
                if (numv4 > MAX_BPF_ADDRS) numv4 = MAX_BPF_ADDRS;
                numv6 = MAX_BPF_ADDRS - numv4;
                }

        LogSPS("mDNSPlatformUpdateProxyList: fd %d %-7s MAC  %.6a %d v4 %d v6", x->BPF_fd, x->ifinfo.ifname, &x->ifinfo.MAC, numv4, numv6);

        // Caution: This is a static structure, so we need to be careful that any modifications we make to it
        // are done in such a way that they work correctly when mDNSPlatformUpdateProxyList is called multiple times
        static struct bpf_insn filter[17 + MAX_BPF_ADDRS] =
                {
                BPF_STMT(BPF_LD  + BPF_H   + BPF_ABS, 12),                              // 0 Read Ethertype (bytes 12,13)

                BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, 0x0806, 0, 1),              // 1 If Ethertype == ARP goto next, else 3
                BPF_STMT(BPF_RET + BPF_K,             42),                              // 2 Return 42-byte ARP

                BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, 0x0800, 4, 0),              // 3 If Ethertype == IPv4 goto 8 (IPv4 address list check) else next

                BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, 0x86DD, 0, 9),              // 4 If Ethertype == IPv6 goto next, else exit
                BPF_STMT(BPF_LD  + BPF_H   + BPF_ABS, 20),                              // 5 Read Protocol and Hop Limit (bytes 20,21)
                BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, 0x3AFF, 0, 9),              // 6 If (Prot,TTL) == (3A,FF) goto next, else IPv6 address list check
                BPF_STMT(BPF_RET + BPF_K,             86),                              // 7 Return 86-byte ND

                // Is IPv4 packet; check if it's addressed to any IPv4 address we're proxying for
                BPF_STMT(BPF_LD  + BPF_W   + BPF_ABS, 30),                              // 8 Read IPv4 Dst (bytes 30,31,32,33)
                };

        struct bpf_insn *pc   = &filter[9];
        struct bpf_insn *chk6 = pc   + numv4 + 1;       // numv4 address checks, plus a "return 0"
        struct bpf_insn *fail = chk6 + 1 + numv6;       // Get v6 Dst LSW, plus numv6 address checks
        struct bpf_insn *ret4 = fail + 1;
        struct bpf_insn *ret6 = ret4 + 4;

        static const struct bpf_insn rf  = BPF_STMT(BPF_RET + BPF_K, 0);                                // No match: Return nothing

        static const struct bpf_insn g6  = BPF_STMT(BPF_LD  + BPF_W   + BPF_ABS, 50);   // Read IPv6 Dst LSW (bytes 50,51,52,53)

        static const struct bpf_insn r4a = BPF_STMT(BPF_LDX + BPF_B   + BPF_MSH, 14);   // Get IP Header length (normally 20)
        static const struct bpf_insn r4b = BPF_STMT(BPF_LD  + BPF_IMM,           54);   // A = 54 (14-byte Ethernet plus 20-byte TCP + 20 bytes spare)
        static const struct bpf_insn r4c = BPF_STMT(BPF_ALU + BPF_ADD + BPF_X,    0);   // A += IP Header length
        static const struct bpf_insn r4d = BPF_STMT(BPF_RET + BPF_A, 0);                                // Success: Return Ethernet + IP + TCP + 20 bytes spare (normally 74)

        static const struct bpf_insn r6a = BPF_STMT(BPF_RET + BPF_K, 94);                               // Success: Return Eth + IPv6 + TCP + 20 bytes spare

        BPF_SetOffset(&filter[4], jf, fail);    // If Ethertype not ARP, IPv4, or IPv6, fail
        BPF_SetOffset(&filter[6], jf, chk6);    // If IPv6 but not ICMPv6, go to IPv6 address list check

        // BPF Byte-Order Note
        // The BPF API designers apparently thought that programmers would not be smart enough to use htons
        // and htonl correctly to convert numeric values to network byte order on little-endian machines,
        // so instead they chose to make the API implicitly byte-swap *ALL* values, even literal byte strings
        // that shouldn't be byte-swapped, like ASCII text, Ethernet addresses, IP addresses, etc.
        // As a result, if we put Ethernet addresses and IP addresses in the right byte order, the BPF API
        // will byte-swap and make them backwards, and then our filter won't work. So, we have to arrange
        // that on little-endian machines we deliberately put addresses in memory with the bytes backwards,
        // so that when the BPF API goes through and swaps them all, they end up back as they should be.
        // In summary, if we byte-swap all the non-numeric fields that shouldn't be swapped, and we *don't*
        // swap any of the numeric values that *should* be byte-swapped, then the filter will work correctly.

        // IPSEC capture size notes:
        //  8 bytes UDP header
        //  4 bytes Non-ESP Marker
        // 28 bytes IKE Header
        // --
        // 40 Total. Capturing TCP Header + 20 gets us enough bytes to receive the IKE Header in a UDP-encapsulated IKE packet.

        AuthRecord *rr;
        for (rr = m->ResourceRecords; rr; rr=rr->next)
                if (rr->resrec.InterfaceID == InterfaceID && rr->AddressProxy.type == mDNSAddrType_IPv4)
                        {
                        mDNSv4Addr a = rr->AddressProxy.ip.v4;
                        pc->code = BPF_JMP + BPF_JEQ + BPF_K;
                        BPF_SetOffset(pc, jt, ret4);
                        pc->jf   = 0;
                        pc->k    = (bpf_u_int32)a.b[0] << 24 | (bpf_u_int32)a.b[1] << 16 | (bpf_u_int32)a.b[2] << 8 | (bpf_u_int32)a.b[3];
                        pc++;
                        }
        *pc++ = rf;

        if (pc != chk6) LogMsg("mDNSPlatformUpdateProxyList: pc %p != chk6 %p", pc, chk6);
        *pc++ = g6;     // chk6 points here

        // First cancel any previous ND group memberships we had, then create a fresh socket
        if (x->BPF_mcfd >= 0) close(x->BPF_mcfd);
        x->BPF_mcfd = socket(AF_INET6, SOCK_DGRAM, 0);

        for (rr = m->ResourceRecords; rr; rr=rr->next)
                if (rr->resrec.InterfaceID == InterfaceID && rr->AddressProxy.type == mDNSAddrType_IPv6)
                        {
                        const mDNSv6Addr *const a = &rr->AddressProxy.ip.v6;
                        pc->code = BPF_JMP + BPF_JEQ + BPF_K;
                        BPF_SetOffset(pc, jt, ret6);
                        pc->jf   = 0;
                        pc->k    = (bpf_u_int32)a->b[0x0C] << 24 | (bpf_u_int32)a->b[0x0D] << 16 | (bpf_u_int32)a->b[0x0E] << 8 | (bpf_u_int32)a->b[0x0F];
                        pc++;

                        struct ipv6_mreq i6mr;
                        i6mr.ipv6mr_interface = x->scope_id;
                        i6mr.ipv6mr_multiaddr = *(const struct in6_addr*)&NDP_prefix;
                        i6mr.ipv6mr_multiaddr.s6_addr[0xD] = a->b[0xD];
                        i6mr.ipv6mr_multiaddr.s6_addr[0xE] = a->b[0xE];
                        i6mr.ipv6mr_multiaddr.s6_addr[0xF] = a->b[0xF];

                        // Do precautionary IPV6_LEAVE_GROUP first, necessary to clear stale kernel state
                        mStatus err = setsockopt(x->BPF_mcfd, IPPROTO_IPV6, IPV6_LEAVE_GROUP, &i6mr, sizeof(i6mr));
                        if (err < 0 && (errno != EADDRNOTAVAIL))
                                LogMsg("mDNSPlatformUpdateProxyList: IPV6_LEAVE_GROUP error %d errno %d (%s) group %.16a on %u", err, errno, strerror(errno), &i6mr.ipv6mr_multiaddr, i6mr.ipv6mr_interface);

                        err = setsockopt(x->BPF_mcfd, IPPROTO_IPV6, IPV6_JOIN_GROUP, &i6mr, sizeof(i6mr));
                        if (err < 0 && (errno != EADDRINUSE))   // Joining same group twice can give "Address already in use" error -- no need to report that
                                LogMsg("mDNSPlatformUpdateProxyList: IPV6_JOIN_GROUP error %d errno %d (%s) group %.16a on %u", err, errno, strerror(errno), &i6mr.ipv6mr_multiaddr, i6mr.ipv6mr_interface);
                        
                        LogSPS("Joined IPv6 ND multicast group %.16a for %.16a", &i6mr.ipv6mr_multiaddr, a);
                        }

        if (pc != fail) LogMsg("mDNSPlatformUpdateProxyList: pc %p != fail %p", pc, fail);
        *pc++ = rf;             // fail points here

        if (pc != ret4) LogMsg("mDNSPlatformUpdateProxyList: pc %p != ret4 %p", pc, ret4);
        *pc++ = r4a;    // ret4 points here
        *pc++ = r4b;
        *pc++ = r4c;
        *pc++ = r4d;

        if (pc != ret6) LogMsg("mDNSPlatformUpdateProxyList: pc %p != ret6 %p", pc, ret6);
        *pc++ = r6a;    // ret6 points here

        struct bpf_program prog = { pc - filter, filter };

#if 0
        // For debugging BPF filter program
        unsigned int q;
        for (q=0; q<prog.bf_len; q++)
                LogSPS("mDNSPlatformUpdateProxyList: %2d { 0x%02x, %d, %d, 0x%08x },", q, prog.bf_insns[q].code, prog.bf_insns[q].jt, prog.bf_insns[q].jf, prog.bf_insns[q].k);
#endif

        if (!numv4 && !numv6)
                {
                LogSPS("mDNSPlatformUpdateProxyList: No need for filter");
                if (m->timenow == 0) LogMsg("mDNSPlatformUpdateProxyList: m->timenow == 0");
                // Schedule check to see if we can close this BPF_fd now
                if (!m->p->NetworkChanged) m->p->NetworkChanged = NonZeroTime(m->timenow + mDNSPlatformOneSecond * 2);
                // prog.bf_len = 0; This seems to panic the kernel
                if (x->BPF_fd < 0) return;              // If we've already closed our BPF_fd, no need to generate an error message below
                }

        if (ioctl(x->BPF_fd, BIOCSETF, &prog) < 0) LogMsg("mDNSPlatformUpdateProxyList: BIOCSETF(%d) failed %d (%s)", prog.bf_len, errno, strerror(errno));
        else LogSPS("mDNSPlatformUpdateProxyList: BIOCSETF(%d) successful", prog.bf_len);
        }

mDNSexport void mDNSPlatformReceiveBPF_fd(mDNS *const m, int fd)
        {
        mDNS_Lock(m);
        
        NetworkInterfaceInfoOSX *i;
        for (i = m->p->InterfaceList; i; i = i->next) if (i->BPF_fd == -2) break;
        if (!i) { LogSPS("mDNSPlatformReceiveBPF_fd: No Interfaces awaiting BPF fd %d; closing", fd); close(fd); }
        else
                {
                LogSPS("%s using   BPF fd %d", i->ifinfo.ifname, fd);
        
                struct bpf_version v;
                if (ioctl(fd, BIOCVERSION, &v) < 0)
                        LogMsg("mDNSPlatformReceiveBPF_fd: %d %s BIOCVERSION failed %d (%s)", fd, i->ifinfo.ifname, errno, strerror(errno));
                else if (BPF_MAJOR_VERSION != v.bv_major || BPF_MINOR_VERSION != v.bv_minor)
                        LogMsg("mDNSPlatformReceiveBPF_fd: %d %s BIOCVERSION header %d.%d kernel %d.%d",
                                fd, i->ifinfo.ifname, BPF_MAJOR_VERSION, BPF_MINOR_VERSION, v.bv_major, v.bv_minor);
        
                if (ioctl(fd, BIOCGBLEN, &i->BPF_len) < 0)
                        LogMsg("mDNSPlatformReceiveBPF_fd: %d %s BIOCGBLEN failed %d (%s)", fd, i->ifinfo.ifname, errno, strerror(errno));
        
                if (i->BPF_len > sizeof(m->imsg))
                        {
                        i->BPF_len = sizeof(m->imsg);
                        if (ioctl(fd, BIOCSBLEN, &i->BPF_len) < 0)
                                LogMsg("mDNSPlatformReceiveBPF_fd: %d %s BIOCSBLEN failed %d (%s)", fd, i->ifinfo.ifname, errno, strerror(errno));
                        else LogSPS("mDNSPlatformReceiveBPF_fd: %d %s BIOCSBLEN %d", i->BPF_len);
                        }
        
                static const u_int opt_one = 1;
                if (ioctl(fd, BIOCIMMEDIATE, &opt_one) < 0)
                        LogMsg("mDNSPlatformReceiveBPF_fd: %d %s BIOCIMMEDIATE failed %d (%s)", fd, i->ifinfo.ifname, errno, strerror(errno));
        
                //if (ioctl(fd, BIOCPROMISC, &opt_one) < 0)
                //      LogMsg("mDNSPlatformReceiveBPF_fd: %d %s BIOCPROMISC failed %d (%s)", fd, i->ifinfo.ifname, errno, strerror(errno));
        
                //if (ioctl(fd, BIOCSHDRCMPLT, &opt_one) < 0)
                //      LogMsg("mDNSPlatformReceiveBPF_fd: %d %s BIOCSHDRCMPLT failed %d (%s)", fd, i->ifinfo.ifname, errno, strerror(errno));
        
                struct ifreq ifr;
                mDNSPlatformMemZero(&ifr, sizeof(ifr));
                strlcpy(ifr.ifr_name, i->ifinfo.ifname, sizeof(ifr.ifr_name));
                if (ioctl(fd, BIOCSETIF, &ifr) < 0)
                        { LogMsg("mDNSPlatformReceiveBPF_fd: %d %s BIOCSETIF failed %d (%s)", fd, i->ifinfo.ifname, errno, strerror(errno)); i->BPF_fd = -3; }
                else
                        {
#ifdef __LIB_DISPATCH__
                        i->BPF_fd  = fd;
                        i->BPF_source = dispatch_source_create(DISPATCH_SOURCE_TYPE_READ, fd, 0, dispatch_get_main_queue());
                        if (!i->BPF_source) {LogMsg("mDNSPlatformReceiveBPF_fd: dispatch source create failed");return;}
                        dispatch_source_set_event_handler(i->BPF_source, ^{bpf_callback_dispatch(i);});
                        dispatch_source_set_cancel_handler(i->BPF_source, ^{close(fd);});
                        dispatch_resume(i->BPF_source);
#else
                        CFSocketContext myCFSocketContext = { 0, i, NULL, NULL, NULL };
                        i->BPF_fd  = fd;
                        i->BPF_cfs = CFSocketCreateWithNative(kCFAllocatorDefault, fd, kCFSocketReadCallBack, bpf_callback, &myCFSocketContext);
                        i->BPF_rls = CFSocketCreateRunLoopSource(kCFAllocatorDefault, i->BPF_cfs, 0);
                        CFRunLoopAddSource(i->m->p->CFRunLoop, i->BPF_rls, kCFRunLoopDefaultMode);
#endif
                        mDNSPlatformUpdateProxyList(m, i->ifinfo.InterfaceID);
                        }
                }

        mDNS_Unlock(m);
        }

#endif // APPLE_OSX_mDNSResponder

#if COMPILER_LIKES_PRAGMA_MARK
#pragma mark -
#pragma mark - Key Management
#endif

#ifndef NO_SECURITYFRAMEWORK
mDNSlocal CFArrayRef GetCertChain(SecIdentityRef identity)
        {
        CFMutableArrayRef certChain = NULL;
        if (!identity) { LogMsg("getCertChain: identity is NULL"); return(NULL); }
        SecCertificateRef cert;
        OSStatus err = SecIdentityCopyCertificate(identity, &cert);
        if (err || !cert) LogMsg("getCertChain: SecIdentityCopyCertificate() returned %d", (int) err);
        else
                {
                SecPolicySearchRef searchRef;
                err = SecPolicySearchCreate(CSSM_CERT_X_509v3, &CSSMOID_APPLE_X509_BASIC, NULL, &searchRef);
                if (err || !searchRef) LogMsg("getCertChain: SecPolicySearchCreate() returned %d", (int) err);
                else
                        {
                        SecPolicyRef policy;
                        err = SecPolicySearchCopyNext(searchRef, &policy);
                        if (err || !policy) LogMsg("getCertChain: SecPolicySearchCopyNext() returned %d", (int) err);
                        else
                                {
                                CFArrayRef wrappedCert = CFArrayCreate(NULL, (const void**) &cert, 1, &kCFTypeArrayCallBacks);
                                if (!wrappedCert) LogMsg("getCertChain: wrappedCert is NULL");
                                else
                                        {
                                        SecTrustRef trust;
                                        err = SecTrustCreateWithCertificates(wrappedCert, policy, &trust);
                                        if (err || !trust) LogMsg("getCertChain: SecTrustCreateWithCertificates() returned %d", (int) err);
                                        else
                                                {
                                                err = SecTrustEvaluate(trust, NULL);
                                                if (err) LogMsg("getCertChain: SecTrustEvaluate() returned %d", (int) err);
                                                else
                                                        {
                                                        CFArrayRef rawCertChain;
                                                        CSSM_TP_APPLE_EVIDENCE_INFO *statusChain = NULL;
                                                        err = SecTrustGetResult(trust, NULL, &rawCertChain, &statusChain);
                                                        if (err || !rawCertChain || !statusChain) LogMsg("getCertChain: SecTrustGetResult() returned %d", (int) err);
                                                        else
                                                                {
                                                                certChain = CFArrayCreateMutableCopy(NULL, 0, rawCertChain);
                                                                if (!certChain) LogMsg("getCertChain: certChain is NULL");
                                                                else
                                                                        {
                                                                        // Replace the SecCertificateRef at certChain[0] with a SecIdentityRef per documentation for SSLSetCertificate:
                                                                        // <http://devworld.apple.com/documentation/Security/Reference/secureTransportRef/index.html>
                                                                        CFArraySetValueAtIndex(certChain, 0, identity);
                                                                        // Remove root from cert chain, but keep any and all intermediate certificates that have been signed by the root certificate
                                                                        if (CFArrayGetCount(certChain) > 1) CFArrayRemoveValueAtIndex(certChain, CFArrayGetCount(certChain) - 1);
                                                                        }
                                                                CFRelease(rawCertChain);
                                                                // Do not free statusChain:
                                                                // <http://developer.apple.com/documentation/Security/Reference/certifkeytrustservices/Reference/reference.html> says:
                                                                // certChain: Call the CFRelease function to release this object when you are finished with it.
                                                                // statusChain: Do not attempt to free this pointer; it remains valid until the trust management object is released...
                                                                }
                                                        }
                                                CFRelease(trust);
                                                }
                                        CFRelease(wrappedCert);
                                        }
                                CFRelease(policy);
                                }
                        CFRelease(searchRef);
                        }
                CFRelease(cert);
                }
        return certChain;
        }
#endif /* NO_SECURITYFRAMEWORK */

mDNSexport mStatus mDNSPlatformTLSSetupCerts(void)
        {
#ifdef NO_SECURITYFRAMEWORK
        return mStatus_UnsupportedErr;
#else
        SecIdentityRef                  identity = nil;
        SecIdentitySearchRef    srchRef = nil;
        OSStatus                                err;

        // search for "any" identity matching specified key use
        // In this app, we expect there to be exactly one
        err = SecIdentitySearchCreate(NULL, CSSM_KEYUSE_DECRYPT, &srchRef);
        if (err) { LogMsg("ERROR: mDNSPlatformTLSSetupCerts: SecIdentitySearchCreate returned %d", (int) err); return err; }

        err = SecIdentitySearchCopyNext(srchRef, &identity);
        if (err) { LogMsg("ERROR: mDNSPlatformTLSSetupCerts: SecIdentitySearchCopyNext returned %d", (int) err); return err; }

        if (CFGetTypeID(identity) != SecIdentityGetTypeID())
                { LogMsg("ERROR: mDNSPlatformTLSSetupCerts: SecIdentitySearchCopyNext CFTypeID failure"); return mStatus_UnknownErr; }

        // Found one. Call getCertChain to create the correct certificate chain.
        ServerCerts = GetCertChain(identity);
        if (ServerCerts == nil) { LogMsg("ERROR: mDNSPlatformTLSSetupCerts: getCertChain error"); return mStatus_UnknownErr; }

        return mStatus_NoError;
#endif /* NO_SECURITYFRAMEWORK */
        }

mDNSexport  void  mDNSPlatformTLSTearDownCerts(void)
        {
#ifndef NO_SECURITYFRAMEWORK
        if (ServerCerts) { CFRelease(ServerCerts); ServerCerts = NULL; }
#endif /* NO_SECURITYFRAMEWORK */
        }

// This gets the text of the field currently labelled "Computer Name" in the Sharing Prefs Control Panel
mDNSlocal void GetUserSpecifiedFriendlyComputerName(domainlabel *const namelabel)
        {
        CFStringEncoding encoding = kCFStringEncodingUTF8;
        CFStringRef cfs = SCDynamicStoreCopyComputerName(NULL, &encoding);
        if (cfs)
                {
                CFStringGetPascalString(cfs, namelabel->c, sizeof(*namelabel), kCFStringEncodingUTF8);
                CFRelease(cfs);
                }
        }

// This gets the text of the field currently labelled "Local Hostname" in the Sharing Prefs Control Panel
mDNSlocal void GetUserSpecifiedLocalHostName(domainlabel *const namelabel)
        {
        CFStringRef cfs = SCDynamicStoreCopyLocalHostName(NULL);
        if (cfs)
                {
                CFStringGetPascalString(cfs, namelabel->c, sizeof(*namelabel), kCFStringEncodingUTF8);
                CFRelease(cfs);
                }
        }

mDNSexport mDNSBool DictionaryIsEnabled(CFDictionaryRef dict)
        {
        mDNSs32 val;
        CFNumberRef state = (CFNumberRef)CFDictionaryGetValue(dict, CFSTR("Enabled"));
        if (!state) return mDNSfalse;
        if (!CFNumberGetValue(state, kCFNumberSInt32Type, &val))
                { LogMsg("ERROR: DictionaryIsEnabled - CFNumberGetValue"); return mDNSfalse; }
        return val ? mDNStrue : mDNSfalse;
        }

mDNSlocal mStatus SetupAddr(mDNSAddr *ip, const struct sockaddr *const sa)
        {
        if (!sa) { LogMsg("SetupAddr ERROR: NULL sockaddr"); return(mStatus_Invalid); }

        if (sa->sa_family == AF_INET)
                {
                struct sockaddr_in *ifa_addr = (struct sockaddr_in *)sa;
                ip->type = mDNSAddrType_IPv4;
                ip->ip.v4.NotAnInteger = ifa_addr->sin_addr.s_addr;
                return(mStatus_NoError);
                }

        if (sa->sa_family == AF_INET6)
                {
                struct sockaddr_in6 *ifa_addr = (struct sockaddr_in6 *)sa;
                // Inside the BSD kernel they use a hack where they stuff the sin6->sin6_scope_id
                // value into the second word of the IPv6 link-local address, so they can just
                // pass around IPv6 address structures instead of full sockaddr_in6 structures.
                // Those hacked IPv6 addresses aren't supposed to escape the kernel in that form, but they do.
                // To work around this we always whack the second word of any IPv6 link-local address back to zero.
                if (IN6_IS_ADDR_LINKLOCAL(&ifa_addr->sin6_addr)) ifa_addr->sin6_addr.__u6_addr.__u6_addr16[1] = 0;
                ip->type = mDNSAddrType_IPv6;
                ip->ip.v6 = *(mDNSv6Addr*)&ifa_addr->sin6_addr;
                return(mStatus_NoError);
                }

        LogMsg("SetupAddr invalid sa_family %d", sa->sa_family);
        return(mStatus_Invalid);
        }

mDNSlocal mDNSEthAddr GetBSSID(char *ifa_name)
        {
        mDNSEthAddr eth = zeroEthAddr;
        SCDynamicStoreRef store = SCDynamicStoreCreate(NULL, CFSTR("mDNSResponder:GetBSSID"), NULL, NULL);
        if (!store)
                LogMsg("GetBSSID: SCDynamicStoreCreate failed: %s", SCErrorString(SCError()));
        else
                {
                CFStringRef entityname = CFStringCreateWithFormat(NULL, NULL, CFSTR("State:/Network/Interface/%s/AirPort"), ifa_name);
                if (entityname)
                        {
                        CFDictionaryRef dict = SCDynamicStoreCopyValue(store, entityname);
                        if (dict)
                                {
                                CFRange range = { 0, 6 };               // Offset, length
                                CFDataRef data = CFDictionaryGetValue(dict, CFSTR("BSSID"));
                                if (data && CFDataGetLength(data) == 6) CFDataGetBytes(data, range, eth.b);
                                CFRelease(dict);
                                }
                        CFRelease(entityname);
                        }
                CFRelease(store);
                }
        return(eth);
        }

mDNSlocal int GetMAC(mDNSEthAddr *eth, u_short ifindex)
        {
        struct ifaddrs *ifa;
        for (ifa = myGetIfAddrs(0); ifa; ifa = ifa->ifa_next)
                if (ifa->ifa_addr->sa_family == AF_LINK)
                        {
                        const struct sockaddr_dl *const sdl = (const struct sockaddr_dl *)ifa->ifa_addr;
                        if (sdl->sdl_index == ifindex)
                                { mDNSPlatformMemCopy(eth->b, sdl->sdl_data + sdl->sdl_nlen, 6); return 0; }
                        }
        *eth = zeroEthAddr;
        return -1;
        }

#ifndef SIOCGIFWAKEFLAGS
#define SIOCGIFWAKEFLAGS _IOWR('i', 136, struct ifreq) /* get interface wake property flags */
#endif

#ifndef IF_WAKE_ON_MAGIC_PACKET
#define IF_WAKE_ON_MAGIC_PACKET 0x01
#endif

#ifndef ifr_wake_flags
#define ifr_wake_flags ifr_ifru.ifru_intval
#endif

mDNSlocal mDNSBool NetWakeInterface(NetworkInterfaceInfoOSX *i)
        {
        if (!MulticastInterface(i)     ) return(mDNSfalse);     // We only use Sleep Proxy Service on multicast-capable interfaces
        if (i->ifa_flags & IFF_LOOPBACK) return(mDNSfalse);     // except loopback

        int s = socket(AF_INET, SOCK_DGRAM, 0);
        if (s < 0) { LogMsg("NetWakeInterface socket failed %s error %d errno %d (%s)", i->ifinfo.ifname, s, errno, strerror(errno)); return(mDNSfalse); }

        struct ifreq ifr;
        strlcpy(ifr.ifr_name, i->ifinfo.ifname, sizeof(ifr.ifr_name));
        if (ioctl(s, SIOCGIFWAKEFLAGS, &ifr) < 0)
                {
                // For some strange reason, in /usr/include/sys/errno.h, EOPNOTSUPP is defined to be
                // 102 when compiling kernel code, and 45 when compiling user-level code. Since this
                // error code is being returned from the kernel, we need to use the kernel version.
                #define KERNEL_EOPNOTSUPP 102
                if (errno != KERNEL_EOPNOTSUPP) // "Operation not supported on socket", the expected result on Leopard and earlier
                        LogMsg("NetWakeInterface SIOCGIFWAKEFLAGS %s errno %d (%s)", i->ifinfo.ifname, errno, strerror(errno));
                // If on Leopard or earlier, we get EOPNOTSUPP, so in that case
                // we enable WOL if this interface is not AirPort and "Wake for Network access" is turned on.
                ifr.ifr_wake_flags = (errno == KERNEL_EOPNOTSUPP && !(i)->BSSID.l[0] && i->m->SystemWakeOnLANEnabled) ? IF_WAKE_ON_MAGIC_PACKET : 0;
                }

        close(s);

        // ifr.ifr_wake_flags = IF_WAKE_ON_MAGIC_PACKET;        // For testing with MacBook Air, using a USB dongle that doesn't actually support Wake-On-LAN

        LogSPS("%-6s %#-14a %s WOMP", i->ifinfo.ifname, &i->ifinfo.ip, (ifr.ifr_wake_flags & IF_WAKE_ON_MAGIC_PACKET) ? "supports" : "no");

        return((ifr.ifr_wake_flags & IF_WAKE_ON_MAGIC_PACKET) != 0);
        }

// Returns pointer to newly created NetworkInterfaceInfoOSX object, or
// pointer to already-existing NetworkInterfaceInfoOSX object found in list, or
// may return NULL if out of memory (unlikely) or parameters are invalid for some reason
// (e.g. sa_family not AF_INET or AF_INET6)
mDNSlocal NetworkInterfaceInfoOSX *AddInterfaceToList(mDNS *const m, struct ifaddrs *ifa, mDNSs32 utc)
        {
        mDNSu32 scope_id  = if_nametoindex(ifa->ifa_name);
        mDNSEthAddr bssid = GetBSSID(ifa->ifa_name);

        mDNSAddr ip, mask;
        if (SetupAddr(&ip,   ifa->ifa_addr   ) != mStatus_NoError) return(NULL);
        if (SetupAddr(&mask, ifa->ifa_netmask) != mStatus_NoError) return(NULL);

        NetworkInterfaceInfoOSX **p;
        for (p = &m->p->InterfaceList; *p; p = &(*p)->next)
                if (scope_id == (*p)->scope_id &&
                        mDNSSameAddress(&ip, &(*p)->ifinfo.ip) &&
                        mDNSSameEthAddress(&bssid, &(*p)->BSSID))
                        {
                        debugf("AddInterfaceToList: Found existing interface %lu %.6a with address %#a at %p", scope_id, &bssid, &ip, *p);
                        (*p)->Exists = mDNStrue;
                        // If interface was not in getifaddrs list last time we looked, but it is now, update 'AppearanceTime' for this record
                        if ((*p)->LastSeen != utc) (*p)->AppearanceTime = utc;

                        // If Wake-on-LAN capability of this interface has changed (e.g. because power cable on laptop has been disconnected)
                        // we may need to start or stop or sleep proxy browse operation
                        const mDNSBool NetWake = NetWakeInterface(*p);
                        if ((*p)->ifinfo.NetWake != NetWake)
                                {
                                (*p)->ifinfo.NetWake = NetWake;
                                // If this interface is already registered with mDNSCore, then we need to start or stop its NetWake browse on-the-fly.
                                // If this interface is not already registered (i.e. it's a dormant interface we had in our list
                                // from when we previously saw it) then we mustn't do that, because mDNSCore doesn't know about it yet.
                                // In this case, the mDNS_RegisterInterface() call will take care of starting the NetWake browse if necessary.
                                if ((*p)->Registered)
                                        {
                                        mDNS_Lock(m);
                                        if (NetWake) mDNS_ActivateNetWake_internal  (m, &(*p)->ifinfo);
                                        else         mDNS_DeactivateNetWake_internal(m, &(*p)->ifinfo);
                                        mDNS_Unlock(m);
                                        }
                                }

                        return(*p);
                        }

        NetworkInterfaceInfoOSX *i = (NetworkInterfaceInfoOSX *)mallocL("NetworkInterfaceInfoOSX", sizeof(*i));
        debugf("AddInterfaceToList: Making   new   interface %lu %.6a with address %#a at %p", scope_id, &bssid, &ip, i);
        if (!i) return(mDNSNULL);
        mDNSPlatformMemZero(i, sizeof(NetworkInterfaceInfoOSX));
        i->ifinfo.InterfaceID = (mDNSInterfaceID)(uintptr_t)scope_id;
        i->ifinfo.ip          = ip;
        i->ifinfo.mask        = mask;
        strlcpy(i->ifinfo.ifname, ifa->ifa_name, sizeof(i->ifinfo.ifname));
        i->ifinfo.ifname[sizeof(i->ifinfo.ifname)-1] = 0;
        // We can be configured to disable multicast advertisement, but we want to to support
        // local-only services, which need a loopback address record.
        i->ifinfo.Advertise   = m->DivertMulticastAdvertisements ? ((ifa->ifa_flags & IFF_LOOPBACK) ? mDNStrue : mDNSfalse) : m->AdvertiseLocalAddresses;
        i->ifinfo.McastTxRx   = mDNSfalse; // For now; will be set up later at the end of UpdateInterfaceList

        i->next            = mDNSNULL;
        i->m               = m;
        i->Exists          = mDNStrue;
        i->Flashing        = mDNSfalse;
        i->Occulting       = mDNSfalse;
        i->AppearanceTime  = utc;               // Brand new interface; AppearanceTime is now
        i->LastSeen        = utc;
        i->ifa_flags       = ifa->ifa_flags;
        i->scope_id        = scope_id;
        i->BSSID           = bssid;
        i->sa_family       = ifa->ifa_addr->sa_family;
        i->BPF_fd          = -1;
        i->BPF_mcfd        = -1;
        i->BPF_len         = 0;
        i->Registered      = mDNSNULL;

        // Do this AFTER i->BSSID has been set up
        i->ifinfo.NetWake  = NetWakeInterface(i);
        GetMAC(&i->ifinfo.MAC, scope_id);
        if (i->ifinfo.NetWake && !i->ifinfo.MAC.l[0])
                LogMsg("AddInterfaceToList: Bad MAC address %.6a for %d %s %#a", &i->ifinfo.MAC, scope_id, i->ifinfo.ifname, &ip);

        *p = i;
        return(i);
        }

#if USE_V6_ONLY_WHEN_NO_ROUTABLE_V4
mDNSlocal NetworkInterfaceInfoOSX *FindRoutableIPv4(mDNS *const m, mDNSu32 scope_id)
        {
        NetworkInterfaceInfoOSX *i;
        for (i = m->p->InterfaceList; i; i = i->next)
                if (i->Exists && i->scope_id == scope_id && i->ifinfo.ip.type == mDNSAddrType_IPv4)
                        if (!mDNSv4AddressIsLinkLocal(&i->ifinfo.ip.ip.v4))
                                return(i);
        return(mDNSNULL);
        }
#endif

#if APPLE_OSX_mDNSResponder

#if COMPILER_LIKES_PRAGMA_MARK
#pragma mark -
#pragma mark - AutoTunnel
#endif

#define kRacoonPort 4500

static DomainAuthInfo* AnonymousRacoonConfig = mDNSNULL;

// We arbitrarily limit the message size to 128 bytes (which seems sufficient now) so that
// freeing ELogContext is simpler which is treated as opaque quantity in many places
typedef struct
        {
        char subdomain[32];
        char message[128];
        uuid_t uuid;
        int result;
        } ELogContext;

typedef enum { HTTPGet = 1, HTTPPost } HTTPOperation;
typedef enum { ConfigInvalid = 0, ConfigFetching, ConfigValid } ConfigState;
typedef void (*HTTPClientCallback)(CFMutableDataRef responseData, ELogContext *context);
#define kReadStreamBufferSize                   4096
#define kMaximumResponseSize                    32768
#define kHTTPResponseCodeOK                             200
#define kHTTPResponseCodeAuthFailure    401
#define kHTTPResponseCodeForbidden              403
#define kHTTPResponseCodeNotFound               404

// eReporter configuration needs to be fetched whenever it becomes stale. We fetch it lazily
// when we send the report.
struct eReporterConfiguration {
        CFDictionaryRef eRDict;
        ConfigState eRState;
} eReporterConfig;

typedef struct
        {
        mDNSBool                                authChecked;
        CFHTTPAuthenticationRef authentication;
        CFMutableDataRef                responseData;
        HTTPClientCallback              callback;
        ELogContext                             cbcontext;
        HTTPOperation                   op;
        CFStringRef                     headerFieldName;
        CFStringRef                     headerFieldValue;
        CFDataRef                               bodyData;
        CFStringRef                             url;
        } HTTPDataStreamContext;


// Forward declarations
mDNSlocal void HTTPDataStream(CFStringRef url, HTTPOperation op, CFDataRef bodyData, CFStringRef headerFieldName,
        CFStringRef headerFieldValue, CFHTTPAuthenticationRef auth, CFMutableDictionaryRef credentials,
        HTTPClientCallback callback, ELogContext *context);
mDNSlocal void mDNSReporterLogValidConfig(ELogContext *elog);

mDNSlocal void CancelReadStream(CFReadStreamRef readStream)
        {
        if (readStream)
                {
                CFReadStreamSetClient(readStream, kCFStreamEventNone, NULL, NULL);
                CFReadStreamUnscheduleFromRunLoop(readStream, CFRunLoopGetMain(), kCFRunLoopCommonModes);
                CFReadStreamClose(readStream);
                CFRelease(readStream);
                }
        }

mDNSlocal void CancelHTTPDataStream(CFReadStreamRef stream, HTTPDataStreamContext *context)
        {
        LogInfo("CancelHTTPDataStream: called");
        if (context)
                {
                if (context->authentication) CFRelease(context->authentication);
                if (context->responseData) CFRelease(context->responseData);
                if (context->headerFieldName) CFRelease(context->headerFieldName);
                if (context->headerFieldValue) CFRelease(context->headerFieldValue);
                if (context->bodyData) CFRelease(context->bodyData);
                if (context->url) CFRelease(context->url);
                freeL("HTTPDataStreamContext", context);
                }
        CancelReadStream(stream);
        }

mDNSlocal CFIndex HTTPResponseCode(CFReadStreamRef stream)
        {
        CFIndex errorCode = 0;
        CFHTTPMessageRef responseHeaders = (CFHTTPMessageRef)CFReadStreamCopyProperty(stream, kCFStreamPropertyHTTPResponseHeader);
        if (responseHeaders)
                {
                errorCode = CFHTTPMessageGetResponseStatusCode(responseHeaders);
                CFRelease(responseHeaders);
                }
        return errorCode;
        }

mDNSlocal void RetryWithHTTPAuth(HTTPDataStreamContext *context, CFReadStreamRef stream)
        {
    CFStreamError err;
        DomainAuthInfo *FoundInList;
        CFMutableDictionaryRef  credentials = NULL;

        // Need to use the same authentication object till it goes invalid
        if (!context->authentication)
                {
                CFHTTPMessageRef responseHeader = (CFHTTPMessageRef)CFReadStreamCopyProperty(stream, kCFStreamPropertyHTTPResponseHeader);
                // Get the authentication information from the response.
                context->authentication = CFHTTPAuthenticationCreateFromResponse(NULL, responseHeader);
                CFRelease(responseHeader);
                }

        // Check to see if the authentication is valid for use. Anything could have gone wrong
        // from bad credentials to wrong type of authentication etc.
        if (!context->authentication || !CFHTTPAuthenticationIsValid(context->authentication, &err))
                {
                LogMsg("RetryWithHTTPAuth: ERROR!! Authentication failed");
                if (context->authentication)
                        {
                        // Check for bad credentials and treat these separately
                        if (err.domain == kCFStreamErrorDomainHTTP && (err.error == kCFStreamErrorHTTPAuthenticationBadUserName ||
                                err.error == kCFStreamErrorHTTPAuthenticationBadPassword))
                                {
                                LogMsg("RetryWithHTTPAuth: ERROR!! Bad credentials %d", err.error); 
                                }
                        }
                CancelHTTPDataStream(stream, context);
                return;
        }

        // Do we need username & password?  Not all authentication types require them.
        if (CFHTTPAuthenticationRequiresUserNameAndPassword(context->authentication))
                {
                char username[MAX_DOMAIN_LABEL + 1];


                // Use the first BTMM username and password
                for (FoundInList = (&mDNSStorage)->AuthInfoList; FoundInList; FoundInList = FoundInList->next)
                        if (!FoundInList->deltime && FoundInList->AutoTunnel) break;

                if (!FoundInList)
                        {
                        LogInfo("RetryHTTPWithAuth:  No BTMM credentials");
                        CancelHTTPDataStream(stream, context);
                        return;
                        }

                ConvertDomainLabelToCString_unescaped((domainlabel *)FoundInList->domain.c, username);
                CFStringRef user = CFStringCreateWithBytes(NULL, (const mDNSu8 *)username, strlen(username), kCFStringEncodingASCII, false);
                if (!user)
                        {
                        LogMsg("RetryHTTPWithAuth: ERROR!! CFStringCreateWithBytes error");
                        CancelHTTPDataStream(stream, context);
                        return;
                        }
                CFStringRef pass = CFStringCreateWithBytes(NULL, (const mDNSu8 *)FoundInList->b64keydata, strlen(FoundInList->b64keydata),
                        kCFStringEncodingASCII, false);
                if (!pass)
                        {
                        LogMsg("RetryHTTPWithAuth: ERROR!! CFStringCreateWithBytes error");
                        CFRelease(user);
                        CancelHTTPDataStream(stream, context);
                        return;
                        }
                // Build the credentials dictionary
                credentials = CFDictionaryCreateMutable(NULL, 0, &kCFTypeDictionaryKeyCallBacks, &kCFTypeDictionaryValueCallBacks);
                if (!credentials)
                        {
                        LogMsg("RetryHTTPWithAuth: ERROR!! cannot allocate credentials");
                        CFRelease(user);
                        CFRelease(pass);
                        CancelHTTPDataStream(stream, context);
                        return;
                        }
                CFDictionarySetValue(credentials, kCFHTTPAuthenticationUsername, user);
                CFDictionarySetValue(credentials, kCFHTTPAuthenticationPassword, pass);
                CFRelease(user);
                CFRelease(pass);
        }
        else
                {
                LogMsg("RetryHTTPWithAuth: ERROR!! Unknown authentication method");
                CancelHTTPDataStream(stream, context);
                return;
                }

        HTTPDataStream(context->url, context->op, context->bodyData, context->headerFieldName, context->headerFieldValue,
                context->authentication, credentials, context->callback, &context->cbcontext);

        if (credentials) CFRelease(credentials);

        // Cancel the old one
        CancelHTTPDataStream(stream, context);
        }

mDNSlocal void HTTPDataStreamCallback(CFReadStreamRef stream, CFStreamEventType type, void *info)
        {
        HTTPDataStreamContext *context = (HTTPDataStreamContext *)info;
        CFIndex status;

        status = HTTPResponseCode(stream);

        // if we are forbidden to access, we need to refetch the configuration file.
        // For keeping it simple, we don't retry immediately. When the next message
        // is logged, we will try getting the config file. If we want to modify this
        // in the future to retry now, then we need to know to stop retrying after a
        // few times.
        if ((status == kHTTPResponseCodeNotFound) || (status == kHTTPResponseCodeForbidden))
                {
                if (status == kHTTPResponseCodeNotFound)
                        LogMsg("HTTPDataStreamCallback: ERROR!! Config plist cannot be found");
                else if (status == kHTTPResponseCodeForbidden)
                        LogInfo("HTTPDataStreamCallback: Config plist Forbidden by server");
                if (context->callback) context->callback(context->responseData, &context->cbcontext);
                CancelHTTPDataStream(stream, context);
                return;
                }

        switch (type)
                {
                case kCFStreamEventHasBytesAvailable:
                        {
                        mDNSu8 buffer[kReadStreamBufferSize];
                        CFIndex bytesRead;
                                
                        if (!context->authChecked)
                                {
                                context->authChecked = mDNStrue;
                                if (status == kHTTPResponseCodeAuthFailure)
                                        {
                                        RetryWithHTTPAuth(context, stream);
                                        return;
                                        }
                                }
                                
                        bytesRead = CFReadStreamRead(stream, buffer, sizeof(buffer));
                        if (bytesRead > 0)
                                {
                                CFDataAppendBytes(context->responseData, buffer, bytesRead);
                                if (CFDataGetLength(context->responseData) > kMaximumResponseSize)
                                        {
                                        LogMsg("HTTPDataStreamCallback: ERROR!! Appended max data %d", kMaximumResponseSize);
                                        }
                                else { LogInfo("HTTPDataStreamCallback: successfully appended data of size %ld", bytesRead); return; }
                                }
                        else if (bytesRead < 0)
                                {
                                LogMsg("HTTPDataStreamCallback: ERROR!! CFReadStreamRead returned %ld", bytesRead);
                                }
                        }
                        break;
                case kCFStreamEventEndEncountered:
                        {
                        if (!context->authChecked)
                                {
                                context->authChecked = mDNStrue;
                                if (status == kHTTPResponseCodeAuthFailure)
                                        {
                                        RetryWithHTTPAuth(context, stream);
                                        return;
                                        }
                                }
                        if (status != kHTTPResponseCodeOK)
                                LogMsg("HTTPDataStreamCallback: ERROR!! EndEncountered, statusCode %d, Operation %d", status, context->op);
                        else
                                LogInfo("HTTPDataStreamCallback: HTTP Ok for Operation %d", context->op);
                        if (context->callback) context->callback(context->responseData, &context->cbcontext);
                        }
                        break;
                case kCFStreamEventErrorOccurred:
                        LogInfo("HTTPDataStreamCallback: ERROR!! kCFStreamEventErrorOccurred for Operation %d", context->op);
                        if (context->callback) context->callback(context->responseData, &context->cbcontext);
                        break;
                default:
                        LogMsg("HTTPDataStreamCallback: ERROR!! default case");
                        if (context->callback) context->callback(context->responseData, &context->cbcontext);
                        break;
                }
        CancelHTTPDataStream(stream, context);
}

// Everything needs to be copied or retained locally if need to be accessed beyond function scope
mDNSlocal void HTTPDataStream(CFStringRef url, HTTPOperation op, CFDataRef bodyData, CFStringRef headerFieldName,
        CFStringRef headerFieldValue, CFHTTPAuthenticationRef authentication, CFMutableDictionaryRef credentials,
        HTTPClientCallback callback, ELogContext *cbcontext)
        {
        CFURLRef myURL = NULL;
        CFHTTPMessageRef myRequest = NULL;
        CFReadStreamRef readStream = NULL;
        HTTPDataStreamContext *contextInfo = NULL;
        CFDictionaryRef proxyDict = NULL;

        contextInfo = mallocL("HTTPDataStreamContext", sizeof(HTTPDataStreamContext));
        if (!contextInfo) { LogMsg("HTTPDataStream: mallocL failure"); return; }

        mDNSPlatformMemZero(contextInfo, sizeof(*contextInfo));
        // Need to remember the state, so that if we need to retry with authentication, we can
        // reissue the request
        contextInfo->url = CFRetain(url);
        contextInfo->callback = callback;
        if(cbcontext) memcpy(&contextInfo->cbcontext, cbcontext, sizeof(ELogContext));
        contextInfo->authChecked = mDNSfalse;
        contextInfo->op = op;
        if (authentication) contextInfo->authentication = (CFHTTPAuthenticationRef) CFRetain(authentication);
        if (headerFieldName) contextInfo->headerFieldName = CFRetain(headerFieldName);
        if (headerFieldValue) contextInfo->headerFieldValue = CFRetain(headerFieldValue);
        if (bodyData) contextInfo->bodyData = CFRetain(bodyData);

        myURL = CFURLCreateWithString(kCFAllocatorDefault, url, NULL);
        if (!myURL) { LogMsg("HTTPDataStream: CFURLCreateWithString error"); goto cleanup; }

        CFStringRef requestMethod = op == HTTPGet ? CFSTR("GET") : CFSTR("POST");
        myRequest = CFHTTPMessageCreateRequest(kCFAllocatorDefault, requestMethod, myURL, kCFHTTPVersion1_1);
        if (!myRequest) { LogMsg("HTTPDataStream: CFHTTPMessageCreateRequest error"); goto cleanup; }

        if (bodyData) CFHTTPMessageSetBody(myRequest, bodyData);
        if (headerFieldName) CFHTTPMessageSetHeaderFieldValue(myRequest, headerFieldName, headerFieldValue);

        if (credentials)
                {
                if (!CFHTTPMessageApplyCredentialDictionary(myRequest, contextInfo->authentication, credentials, NULL))
                        {
                        LogMsg("HTTPDataStream: ERROR!! CFHTTPMessageApplyCredentialDictionary error");
                        goto cleanup;
                        }
                }

        readStream = CFReadStreamCreateForHTTPRequest(kCFAllocatorDefault, myRequest);
        if (!readStream) { LogMsg("HTTPDataStream: CFStringCreateWithBytes error"); goto cleanup; }

        proxyDict = SCDynamicStoreCopyProxies(NULL);
        if (proxyDict)
                {
                mDNSBool ret = CFReadStreamSetProperty(readStream, kCFStreamPropertyHTTPProxy, proxyDict);
                CFRelease(proxyDict);
                if (!ret)
                        {
                        LogMsg("HTTPDataStream: CFReadStreamSetProperty HTTP proxy failed");
                        goto cleanup;
                        }
                }

        CFOptionFlags events = kCFStreamEventHasBytesAvailable | kCFStreamEventErrorOccurred | kCFStreamEventEndEncountered;

        CFStreamClientContext readContext = {0, contextInfo, NULL, NULL, NULL};
        CFReadStreamSetClient(readStream, events, HTTPDataStreamCallback, &readContext);
        CFReadStreamScheduleWithRunLoop(readStream, CFRunLoopGetMain(), kCFRunLoopCommonModes);
        if (CFReadStreamOpen(readStream))
                {
                contextInfo->responseData = CFDataCreateMutable(NULL, 0);
                if (contextInfo->responseData)
                        {
                        // Release the things that we don't need
                        CFRelease(myURL);
                        CFRelease(myRequest);
                        return;
                        }
                LogMsg("HTTPDataStream: ERROR!! responseData allocation failed");
                }
        else LogMsg("HTTPDataStream: ERROR!! CFReadStreamOpen failed");
cleanup:
        if (readStream) CancelReadStream(readStream);
        if (myRequest) CFRelease(myRequest);
        if (myURL) CFRelease(myURL);
        if (contextInfo)
                {
                if (contextInfo->authentication) CFRelease(contextInfo->authentication);
                if (contextInfo->headerFieldName) CFRelease(contextInfo->headerFieldName);
                if (contextInfo->headerFieldValue) CFRelease(contextInfo->headerFieldValue);
                if (contextInfo->bodyData) CFRelease(contextInfo->bodyData);
                if (contextInfo->url) CFRelease(contextInfo->url);
                freeL("HTTPDataStreamContext", contextInfo);
                }
        }

mDNSlocal CFStringRef eReporterGetValueForKey(CFDictionaryRef dict, char *keyCString)
        {
        CFStringRef value;
        CFStringRef key;

        key = CFStringCreateWithCString(NULL, keyCString, kCFStringEncodingUTF8);
        if (!CFDictionaryContainsKey(dict, key))
                {
                LogMsg("eReporterGetValueForKey: ERROR!! key %s not found", keyCString);
                return NULL;
                }
        value = (CFStringRef)CFDictionaryGetValue(dict, key);
        CFRelease(key);
        if (!value)
                {
                LogMsg("eReporterGetValueForKey: ERROR!! value not found for %s", keyCString);
                return NULL;
                }
        return value;
        }
        
mDNSlocal void eReporterConfigCallback(CFMutableDataRef responseData, ELogContext *context)
        {
        CFDictionaryRef dict = NULL;
        char *plistKeys[] = {"URL", "Publish", "LoadText", "URI", NULL};
        int i;
        CFErrorRef error;

        if (!CFDataGetLength(responseData))
                {
                LogInfo("eReporterConfigCallback: Zero length data");
                eReporterConfig.eRState = ConfigInvalid;
                return;
                }
        CFPropertyListFormat format = kCFPropertyListXMLFormat_v1_0;
        dict = CFPropertyListCreateWithData(0, responseData, kCFPropertyListImmutable, &format, &error);
        if ( dict == NULL )
                {
                LogMsg("eReporterConfigCallback: Parsing property list failed");
                eReporterConfig.eRState = ConfigInvalid;
                CFRelease(error);
                return;
                }
        i = 0;
        while (plistKeys[i] != NULL)
                {
                if (eReporterGetValueForKey(dict, plistKeys[i]) == NULL)
                        {
                        LogMsg("eReporterConfigCallback: ERROR!! problem accessing key %s", plistKeys[i]);
                        CFRelease(dict);
                        eReporterConfig.eRState = ConfigInvalid;
                        return;
                        }
                i++;
                }
        if (eReporterConfig.eRDict) CFRelease(eReporterConfig.eRDict);
        eReporterConfig.eRDict = dict;
        eReporterConfig.eRState = ConfigValid;
        mDNSReporterLogValidConfig(context);
        }

mDNSlocal mDNSBool FetchEReporterConfiguration(ELogContext *context)
        {
        const char *urlString = "https://configuration.apple.com./configurations/internetservices/e3/mDNSResponder/Configurations1.0.plist";
        //const char *urlString = "http://isdev02:9702/configuration/configurations/internetservices/e3/btmm/Configurations1.0.plist"; //dev server

        CFStringRef url = CFStringCreateWithBytes(NULL, (const mDNSu8 *)urlString, strlen(urlString), kCFStringEncodingASCII, false);
        if (!url) { LogMsg("FetchEReporterConfiguration: CFStringCreateWithBytes error"); return mDNSfalse; }

        if (eReporterConfig.eRState == ConfigValid || eReporterConfig.eRState == ConfigFetching)
                {
                CFRelease(url);
                return mDNSfalse;
                }

        eReporterConfig.eRState = ConfigFetching;
        HTTPDataStream(url, HTTPGet, NULL, NULL, NULL, NULL, NULL, eReporterConfigCallback, context);
        CFRelease(url);
        return mDNStrue;
        }

// Builds an element of type : <key name="nameAttr"> value </key> and attaches it to
// xmlTree
mDNSlocal mDNSBool AddElementToTree(CFXMLTreeRef xmlTree, char *nameAttr, char *value)
        {
        /* <key name="BTMM domain"> domain </key> */

        CFStringRef textval = CFStringCreateWithCString(NULL, value, kCFStringEncodingUTF8);
        if (!textval) { LogMsg("AddElementToTree: cannot create CString for value %s", value); return mDNSfalse; }

        CFStringRef keys[1] = { CFSTR("name") };
        CFStringRef values[1] = { CFStringCreateWithCString(NULL, nameAttr, kCFStringEncodingUTF8) };

        CFDictionaryRef dict = CFDictionaryCreate(NULL, (void*)keys, (void*)values, 1, &kCFTypeDictionaryKeyCallBacks,
                &kCFTypeDictionaryValueCallBacks);
        if (!dict)
                {
                LogMsg("AddElementToTree: ERROR!! CFDictionaryCreate failed for %s", nameAttr);
                CFRelease(textval);
                CFRelease(values[0]);
                return mDNSfalse;
                }

        CFMutableArrayRef attr = CFArrayCreateMutable(NULL, 0, &kCFTypeArrayCallBacks);
        if (!attr)
                {
                LogMsg("AddElementToTree: ERROR!! CFArrayCreateMutable failed for %s", nameAttr);
                CFRelease(textval);
                CFRelease(dict);
                CFRelease(values[0]);
                return mDNSfalse;
                }

        CFArrayAppendValue(attr, keys[0]);

        /* Build <key name="nameAttr"> */

        CFXMLElementInfo nameInfo;
        nameInfo.attributes = (CFDictionaryRef)dict;
        nameInfo.attributeOrder = (CFArrayRef) attr;
        nameInfo.isEmpty = mDNSfalse;   
        CFXMLNodeRef nameNode = CFXMLNodeCreate(kCFAllocatorDefault, kCFXMLNodeTypeElement, CFSTR("key"), &nameInfo,
                kCFXMLNodeCurrentVersion);      
        CFXMLTreeRef nameTree = CFXMLTreeCreateWithNode(kCFAllocatorDefault, nameNode);
        CFTreeAppendChild(xmlTree, nameTree);
        CFRelease(nameNode);
        CFRelease(attr);
        CFRelease(dict);
        CFRelease(values[0]);

        /* Build the rest: value </key> */

        CFXMLNodeRef nameTextNode = CFXMLNodeCreate(kCFAllocatorDefault, kCFXMLNodeTypeText, textval, NULL,
           kCFXMLNodeCurrentVersion);   
        CFXMLTreeRef nameTextTree = CFXMLTreeCreateWithNode(kCFAllocatorDefault, nameTextNode);
        CFTreeAppendChild(nameTree, nameTextTree);
        CFRelease(nameTextTree);
        CFRelease(nameTextNode);
        CFRelease(textval);

        // Now that we are done with nameTree, we can release it
        CFRelease(nameTree);

        return mDNStrue;
        }

mDNSlocal void LogPOSTArgs(CFStringRef finalURL, CFStringRef LoadTextName, CFStringRef LoadTextValue, CFDataRef bodyData)
        {
        char buf1[128], buf2[64], buf3[64], buf4[1024];

        if (!CFStringGetCString(finalURL, buf1, sizeof(buf1), kCFStringEncodingUTF8) ||
                !CFStringGetCString(LoadTextName, buf2, sizeof(buf2), kCFStringEncodingUTF8) ||
                !CFStringGetCString(LoadTextValue, buf3, sizeof(buf3), kCFStringEncodingUTF8))
                {
                LogMsg("mDNSEReportPOSTArgs: Error in parsing arguments");
                return; 
                }
        CFStringRef bstr = CFStringCreateFromExternalRepresentation(NULL, bodyData, kCFStringEncodingUTF8);
        buf4[0] = 0;
        if (!CFStringGetCString(bstr, buf4, sizeof(buf4), kCFStringEncodingUTF8))
                {
                LogMsg("mDNSEReportPOSTArgs: buf4 cstring conversion problem");
                }
        if (bstr) CFRelease(bstr);
        LogInfo("LogPOSTArgs: URL : %s, LoadTextName: %s, LoadTextValue: %s, bodyData %s", buf1, buf2, buf3, buf4);
        }

// This function is called when there is a valid configuration for eReporter service
// We add the following:
//
// <key name="uuid"> uuid </key>
// <key name="Subdomain"> subdomain </key>
// <key name="Message"> message </key>
// <key name="Time"> YYYY-MM-DD HH24:MI:SS </key>
// <key name="SPS"> True/False </key>
// <key name="Result"> Success/Fail </key>
//
// if result is -1, result won't be added. 1 means "Failed" and 0 means "Success"
//
mDNSlocal void mDNSReporterLogValidConfig(ELogContext *elog)
        {
        CFMutableStringRef finalURL = NULL;
        CFStringRef LoadTextName = NULL;
        CFDataRef bodyData = NULL;
        CFBooleanRef pub;
        CFXMLTreeRef appTree = NULL;

        pub = (CFBooleanRef)eReporterGetValueForKey(eReporterConfig.eRDict, "Publish");
        if (pub == NULL)
                {
                LogMsg("mDNSReporterLogValidConfig: Publish key does not exist");
                return;
                }

        Boolean pubVal = CFBooleanGetValue(pub);
        if (!pubVal)
                {
                // Set the config state to invalid so that we will refetch the configuration next time
                // in case Publish value changes between now and then
                eReporterConfig.eRState = ConfigInvalid;
                LogInfo("mDNSReporterLogValidConfig: Value for Publish is %d", pubVal);
                return;
                }

        CFXMLDocumentInfo documentInfo;
        documentInfo.sourceURL = NULL;
        documentInfo.encoding = kCFStringEncodingUTF8;
        CFXMLNodeRef docNode = CFXMLNodeCreate( kCFAllocatorDefault, kCFXMLNodeTypeDocument, CFSTR(""), &documentInfo,
                kCFXMLNodeCurrentVersion);
        CFXMLTreeRef xmlDocument = CFXMLTreeCreateWithNode(kCFAllocatorDefault, docNode);
        CFRelease(docNode);

        /* <?xml version="1.0" encoding="utf-8"?> */
        CFXMLProcessingInstructionInfo instructionInfo;
        instructionInfo.dataString = CFSTR("version=\"1.0\" encoding=\"utf-8\"");
        CFXMLNodeRef instructionNode = CFXMLNodeCreate(NULL, kCFXMLNodeTypeProcessingInstruction, CFSTR("xml"),
                &instructionInfo, kCFXMLNodeCurrentVersion);
        CFXMLTreeRef instructionTree = CFXMLTreeCreateWithNode(kCFAllocatorDefault, instructionNode);
        CFTreeAppendChild(xmlDocument, instructionTree);
        CFRelease(instructionTree);
        CFRelease(instructionNode);

        /* Root Element: <app name="mDNSResponder" version="XXX"> */

        CFStringRef appKeys[2] = { CFSTR("name"), CFSTR("version") };
        CFStringRef appValues[2] = { CFStringCreateWithCString(NULL, "mDNSResponder", kCFStringEncodingUTF8),
                                                                 CFStringCreateWithCString(NULL, STRINGIFY(mDNSResponderVersion), kCFStringEncodingUTF8) };

        CFDictionaryRef appDict = CFDictionaryCreate(NULL, (void*)appKeys, (void*)appValues, 2, &kCFTypeDictionaryKeyCallBacks,
                &kCFTypeDictionaryValueCallBacks);
        if (!appDict) { LogMsg("mDNSEReporterLogValidConfig: CFDictionaryCreate App failed"); goto cleanup; }

        CFMutableArrayRef appAttr = CFArrayCreateMutable(NULL, 0, &kCFTypeArrayCallBacks);
        if (!appAttr) { LogMsg("mDNSEReporterLogValidConfig: CFArrayCreateMutable App failed"); goto cleanup; }

        CFArrayAppendValue(appAttr, appKeys[0]);
        CFArrayAppendValue(appAttr, appKeys[1]);

        CFXMLElementInfo appInfo;
        appInfo.attributes = (CFDictionaryRef) appDict;
        appInfo.attributeOrder = (CFArrayRef) appAttr;
        appInfo.isEmpty = mDNSfalse;
        CFXMLNodeRef appNode = CFXMLNodeCreate ( kCFAllocatorDefault, kCFXMLNodeTypeElement, CFSTR("app"), &appInfo,
                kCFXMLNodeCurrentVersion);      
        appTree = CFXMLTreeCreateWithNode(kCFAllocatorDefault, appNode);
        CFTreeAppendChild(xmlDocument, appTree);
        CFRelease(appNode);
        CFRelease(appAttr);
        CFRelease(appDict);
        CFRelease(appValues[0]);
        CFRelease(appValues[1]);
        // appTree will be released at the end as we will be appeneding other nodes to appTree below

        char            uuidStr[37];
        uuid_unparse(elog->uuid, uuidStr);
        AddElementToTree(appTree, "UUID", uuidStr);

        AddElementToTree(appTree, "Subdomain", elog->subdomain);
        AddElementToTree(appTree, "Message", elog->message);

        char tm_buffer[128];
        time_t t = time(NULL);
        struct tm *tm_t = gmtime(&t);
        mDNS_snprintf(tm_buffer, sizeof(tm_buffer), "%4d-%02d-%02d %02d:%02d:%02d", tm_t->tm_year + 1900, tm_t->tm_mon + 1,
                tm_t->tm_mday, tm_t->tm_hour, tm_t->tm_min, tm_t->tm_sec);
        AddElementToTree(appTree, "Time", tm_buffer);

        const CacheRecord *sps[3] = { mDNSNULL };
        NetworkInterfaceInfo *intf;
        mDNSBool SleepProxy = mDNSfalse;
        for (intf = GetFirstActiveInterface(mDNSStorage.HostInterfaces); intf; intf = GetFirstActiveInterface(intf->next))
                {
                if (intf->NetWake)
                        {
                        FindSPSInCache(&mDNSStorage, &intf->NetWakeBrowse, sps);
                        if (sps[0])
                                {
                                SleepProxy = mDNStrue;
                                break;
                                }
                        }
                else { LogInfo("mDNSEReporterValidConfig: NetWake is not set %p", intf->InterfaceID); }
                }
        AddElementToTree(appTree, "SPS", (SleepProxy ? "True" : "False"));

        if (elog->result != -1)
                AddElementToTree(appTree, "Result", elog->result ? "fail" : "success");

        bodyData = CFXMLTreeCreateXMLData(NULL, xmlDocument);
        if (!bodyData) { LogMsg("mDNSEReporterLogValidConfig: CFXMLTreeCreateData failed for bodyData"); goto cleanup; }

        CFStringRef url = eReporterGetValueForKey(eReporterConfig.eRDict, "URL");
        if (!url) { LogMsg("mDNSEReporterLogValidConfig: eReporterGetValueForKey failed for URL"); goto cleanup; }

        CFStringRef uri = eReporterGetValueForKey(eReporterConfig.eRDict, "URI");
        if (!uri) { LogMsg("mDNSEReporterLogValidConfig: eReporterGetValueForKey failed for URI"); goto cleanup; }

        finalURL = CFStringCreateMutable(NULL, 0);
        if (!finalURL) { LogMsg("mDNSEReporterLogValidConfig: CFStringCreateMutable failed for finalURL"); goto cleanup; }

        CFStringAppend(finalURL, url);
        CFStringAppend(finalURL, uri);

        LoadTextName = CFStringCreateWithCString(NULL, "x-LoadText", kCFStringEncodingUTF8);
        if (!LoadTextName) { LogMsg("mDNSEReporterLogValidConfig: CFStringCreateWithCString failed for LoadText"); goto cleanup; }

        CFStringRef LoadTextValue = eReporterGetValueForKey(eReporterConfig.eRDict, "LoadText");        
        if (!LoadTextValue) { LogMsg("mDNSEReporterLogValidConfig: eReporterGetValueForKey failed for LoadTextValue"); goto cleanup; }

        LogPOSTArgs(finalURL, LoadTextName, LoadTextValue, bodyData);

        // we don't have a callback for the POST. If there is an error in POST, it will be logged
        // by the callback of HTTPDataStream
        HTTPDataStream(finalURL, HTTPPost, bodyData, LoadTextName, LoadTextValue, NULL, NULL, NULL, NULL);

cleanup:
        // Free whatever was allocated in this function
        if (bodyData) CFRelease(bodyData);
        if (finalURL) CFRelease(finalURL);
        if (LoadTextName) CFRelease(LoadTextName);
        if (appTree) CFRelease(appTree);
        CFRelease(xmlDocument);
        }

mDNSlocal void mDNSEReporterLog(uuid_t *uuid, const char *subdomain, int result, char *message)
        {
        // We allocate ELogContext and free it at the end of the function. It is the
        // responsibility of the called function to copy it if it needs to hold
        // on to it
        ELogContext *info = mallocL("ELogContext", sizeof (ELogContext));
        if (!info) { LogMsg("mDNSEReporterLog: malloc failed"); return; }

        // Take a local copy of all the log information
        strlcpy(info->subdomain, subdomain, sizeof(info->subdomain));
        strlcpy(info->message, message, sizeof(info->message));
        info->result = result;
        uuid_copy(info->uuid, *uuid);
        if (eReporterConfig.eRState != ConfigValid)
                {
                // Currently we can't have two outstanding configuration fetches. If we have two quick
                // back to back logs while the configuration is being fetched, we log only the first
                // message to EReporter. If the configuration is valid (common case), then we don't
                // drop any messages
                if (!FetchEReporterConfiguration(info))
                        {
                        LogInfo("mDNSEReporterLog: Configuration being fetched.., Not logging");
                        }
                freeL("ELogContext", info);
                return;
                }
        mDNSReporterLogValidConfig(info);
        freeL("ELogContext", info);
        }

#ifndef NO_SECURITYFRAMEWORK

static CFMutableDictionaryRef domainStatusDict = NULL;

// MUST be called with lock held
mDNSlocal void RemoveAutoTunnelDomainStatus(const mDNS *const m, const DomainAuthInfo *const info)
        {
        char buffer[1024];
        CFStringRef domain;

        LogInfo("RemoveAutoTunnelDomainStatus: %##s", info->domain.c);

        if (!domainStatusDict) { LogMsg("RemoveAutoTunnelDomainStatus: No domainStatusDict"); return; }
        
        buffer[mDNS_snprintf(buffer, sizeof(buffer), "%##s", info->domain.c) - 1] = 0;
        domain = CFStringCreateWithCString(NULL, buffer, kCFStringEncodingUTF8);
        if (!domain) { LogMsg("RemoveAutoTunnelDomainStatus: Could not create CFString domain"); return; }
        
        if (CFDictionaryContainsKey(domainStatusDict, domain))
                {
                CFDictionaryRemoveValue(domainStatusDict, domain);
                if (!m->ShutdownTime) mDNSDynamicStoreSetConfig(kmDNSBackToMyMacConfig, mDNSNULL, domainStatusDict);
                }
        CFRelease(domain);
        }

mDNSlocal mStatus CheckQuestionForStatus(const DNSQuestion *const q)
        {
        if (q->LongLived)
                {
                if (q->servAddr.type == mDNSAddrType_IPv4 && mDNSIPv4AddressIsOnes(q->servAddr.ip.v4))
                        return mStatus_NoSuchRecord;
                else if (q->state == LLQ_Poll)
                        return mStatus_PollingMode;
                else if (q->state != LLQ_Established && !q->DuplicateOf)
                        return mStatus_TransientErr;
                }
        
        return mStatus_NoError;
}

mDNSlocal mStatus UpdateLLQStatus(const mDNS *const m, char *buffer, int bufsz, const DomainAuthInfo *const info)
        {
        mStatus status = mStatus_NoError;
        DNSQuestion* q, *worst_q = mDNSNULL;
        for (q = m->Questions; q; q=q->next)
                if (q->AuthInfo == info)
                        {
                        mStatus newStatus = CheckQuestionForStatus(q);
                        if              (newStatus == mStatus_NoSuchRecord) { status = newStatus; worst_q = q; break; }
                        else if (newStatus == mStatus_PollingMode)  { status = newStatus; worst_q = q; }
                        else if (newStatus == mStatus_TransientErr && status == mStatus_NoError) { status = newStatus; worst_q = q; }
                        }
        
        if      (status == mStatus_NoError)      mDNS_snprintf(buffer, bufsz, "Success");
        else if (status == mStatus_NoSuchRecord) mDNS_snprintf(buffer, bufsz, "GetZoneData %s: %##s", worst_q->nta ? "not yet complete" : "failed", worst_q->qname.c);
        else if (status == mStatus_PollingMode)  mDNS_snprintf(buffer, bufsz, "Query polling %##s", worst_q->qname.c);
        else if (status == mStatus_TransientErr) mDNS_snprintf(buffer, bufsz, "Query not yet established %##s", worst_q->qname.c);
        return status;
        }

mDNSlocal mStatus UpdateRRStatus(const mDNS *const m, char *buffer, int bufsz, const DomainAuthInfo *const info)
        {
        AuthRecord *r;

        if (info->deltime) return mStatus_NoError;
        for (r = m->ResourceRecords; r; r = r->next)
                {
                // This function is called from UpdateAutoTunnelDomainStatus which in turn may be called from
                // a callback e.g., CheckNATMappings. GetAuthInfoFor_internal does not like that (reentrancy being 1),
                // hence we inline the code here. We just need the lock to walk the list of AuthInfos which the caller
                // has already checked
                const domainname *n = r->resrec.name;
                while (n->c[0])
                        {
                        DomainAuthInfo *ptr;
                        for (ptr = m->AuthInfoList; ptr; ptr = ptr->next)
                                if (SameDomainName(&ptr->domain, n))
                                        {
                                        if (ptr == info && r->updateError == mStatus_BadSig)
                                                {
                                                mDNS_snprintf(buffer, bufsz, "Resource record update failed for %##s", r->resrec.name);
                                                return r->updateError;
                                                }
                                        }
                        n = (const domainname *)(n->c + 1 + n->c[0]);
                        }
                }
        return mStatus_NoError;
        }

#endif // ndef NO_SECURITYFRAMEWORK

// MUST be called with lock held
mDNSlocal void UpdateAutoTunnelDomainStatus(const mDNS *const m, const DomainAuthInfo *const info)
        {
#ifdef NO_SECURITYFRAMEWORK
        (void)m;
        (void)info;
#else
        const NATTraversalInfo *const llq = m->LLQNAT.clientContext ? &m->LLQNAT : mDNSNULL;
        const NATTraversalInfo *const tun = info->AutoTunnelNAT.clientContext ? &info->AutoTunnelNAT : mDNSNULL;
        char buffer[1024];
        CFMutableDictionaryRef dict = CFDictionaryCreateMutable(NULL, 0, &kCFTypeDictionaryKeyCallBacks, &kCFTypeDictionaryValueCallBacks);
        CFStringRef domain = NULL;
        CFStringRef tmp = NULL;
        CFNumberRef num = NULL;
        mStatus status = mStatus_NoError;
        
        if (!m->mDNS_busy) LogMsg("UpdateAutoTunnelDomainStatus: ERROR!! Lock not held");
        if (!domainStatusDict)
                {
                domainStatusDict = CFDictionaryCreateMutable(NULL, 0, &kCFTypeDictionaryKeyCallBacks, &kCFTypeDictionaryValueCallBacks);
                if (!domainStatusDict) { LogMsg("UpdateAutoTunnelDomainStatus: Could not create CFDictionary domainStatusDict"); return; }
                }
        
        if (!dict) { LogMsg("UpdateAutoTunnelDomainStatus: Could not create CFDictionary dict"); return; }

        buffer[mDNS_snprintf(buffer, sizeof(buffer), "%##s", info->domain.c) - 1] = 0;
        domain = CFStringCreateWithCString(NULL, buffer, kCFStringEncodingUTF8);
        if (!domain) { LogMsg("UpdateAutoTunnelDomainStatus: Could not create CFString domain"); return; }

        mDNS_snprintf(buffer, sizeof(buffer), "%#a", &m->Router);
        tmp = CFStringCreateWithCString(NULL, buffer, kCFStringEncodingUTF8);
        if (!tmp)
                LogMsg("UpdateAutoTunnelDomainStatus: Could not create CFString RouterAddress");
        else
                {
                CFDictionarySetValue(dict, CFSTR("RouterAddress"), tmp);
                CFRelease(tmp);
                }
        
        mDNS_snprintf(buffer, sizeof(buffer), "%.4a", &m->ExternalAddress);
        tmp = CFStringCreateWithCString(NULL, buffer, kCFStringEncodingUTF8);
        if (!tmp)
                LogMsg("UpdateAutoTunnelDomainStatus: Could not create CFString ExternalAddress");
        else
                {
                CFDictionarySetValue(dict, CFSTR("ExternalAddress"), tmp);
                CFRelease(tmp);
                }
        
        if (llq)
                {
                mDNSu32 port = mDNSVal16(llq->ExternalPort);
                
                num = CFNumberCreate(NULL, kCFNumberSInt32Type, &port);
                if (!num)
                        LogMsg("UpdateAutoTunnelDomainStatus: Could not create CFNumber LLQExternalPort");
                else
                        {
                        CFDictionarySetValue(dict, CFSTR("LLQExternalPort"), num);
                        CFRelease(num);
                        }

                if (llq->Result)
                        {
                        num = CFNumberCreate(NULL, kCFNumberSInt32Type, &llq->Result);
                        if (!num)
                                LogMsg("UpdateAutoTunnelDomainStatus: Could not create CFNumber LLQNPMStatus");
                        else
                                {
                                CFDictionarySetValue(dict, CFSTR("LLQNPMStatus"), num);
                                CFRelease(num);
                                }
                        }
                }
        
        if (tun)
                {
                mDNSu32 port = mDNSVal16(tun->ExternalPort);
                
                num = CFNumberCreate(NULL, kCFNumberSInt32Type, &port);
                if (!num)
                        LogMsg("UpdateAutoTunnelDomainStatus: Could not create CFNumber AutoTunnelExternalPort");
                else
                        {
                        CFDictionarySetValue(dict, CFSTR("AutoTunnelExternalPort"), num);
                        CFRelease(num);
                        }

                if (tun->Result)
                        {
                        num = CFNumberCreate(NULL, kCFNumberSInt32Type, &tun->Result);
                        if (!num)
                                LogMsg("UpdateAutoTunnelDomainStatus: Could not create CFNumber AutoTunnelNPMStatus");
                        else
                                {
                                CFDictionarySetValue(dict, CFSTR("AutoTunnelNPMStatus"), num);
                                CFRelease(num);
                                }
                        }
                }
        if (tun || llq)
                {
                mDNSu32 code = m->LastNATMapResultCode;
                
                num = CFNumberCreate(NULL, kCFNumberSInt32Type, &code);
                if (!num)
                        LogMsg("UpdateAutoTunnelDomainStatus: Could not create CFNumber LastNATMapResultCode");
                else
                        {
                        CFDictionarySetValue(dict, CFSTR("LastNATMapResultCode"), num);
                        CFRelease(num);
                        }
                }
        
        // If we have a relay address, check the LLQ status as they don't go over the relay connection.
        // If LLQs fail, then report failure. In future, when LLQs go over the relay connection, we don't
        // need this logic
        if (!mDNSIPv6AddressIsZero(m->AutoTunnelRelayAddr))
                {
                // If we have a bad signature error updating RR, it overrides any error as
                // the user needs to be notified immediately 
                status = UpdateRRStatus(m, buffer, sizeof(buffer), info);
                if (status == mStatus_NoError)  
                        {
                        status = UpdateLLQStatus(m, buffer, sizeof(buffer), info);
                        if (status == mStatus_PollingMode)      
                                {
                                // If we have a relay connection and we are in polling mode, report as success.
                                // This normally happens when we are behind Double NAT or NAT with UPnP/NAT-PMP
                                // disabled but we are able to successfully file share/screen share with the help
                                // of the relay connection. As it just affects the discovery/update of the other
                                // BTMM hosts, we consider it as minor issue and report it as success.
                                LogInfo("UpdateAutoTunnelDomainStatus:NonzeroRelayAddress: Polling reported as success");
                                status = mStatus_NoError;
                                mDNS_snprintf(buffer, sizeof(buffer), "Success");
                                }
                        }
                LogInfo("UpdateAutoTunnelDomainStatus:NonzeroRelayAddress: Status %d, %s", status, buffer);
                }
        else if (!llq && !tun)
                {
                status = mStatus_NotInitializedErr;
                mDNS_snprintf(buffer, sizeof(buffer), "Neither LLQ nor AutoTunnel NAT port mapping is currently active");
                }
        else if ((llq && llq->Result == mStatus_DoubleNAT) || (tun && tun->Result == mStatus_DoubleNAT))
                {
                status = mStatus_DoubleNAT;
                mDNS_snprintf(buffer, sizeof(buffer), "Double NAT: Router is reporting an external address");
                }
        else if ((llq && llq->Result == mStatus_NATPortMappingDisabled) || (tun && tun->Result == mStatus_NATPortMappingDisabled) ||
                 (m->LastNATMapResultCode == NATErr_Refused && ((llq && !llq->Result && mDNSIPPortIsZero(llq->ExternalPort)) || (tun && !tun->Result && mDNSIPPortIsZero(tun->ExternalPort)))))
                {
                status = mStatus_NATPortMappingDisabled;
                mDNS_snprintf(buffer, sizeof(buffer), "NAT-PMP is disabled on the router");
                }
        else if ((llq && llq->Result) || (tun && tun->Result))
                {
                status = mStatus_NATTraversal;
                mDNS_snprintf(buffer, sizeof(buffer), "Error obtaining NAT port mapping from router");
                }
        else if (m->Router.type == mDNSAddrType_None)
                {
                status = mStatus_NoRouter;
                mDNS_snprintf(buffer, sizeof(buffer), "No network connection - none");
                }
        else if (m->Router.type == mDNSAddrType_IPv4 && mDNSIPv4AddressIsZero(m->Router.ip.v4))
                {
                status = mStatus_NoRouter;
                mDNS_snprintf(buffer, sizeof(buffer), "No network connection - v4 zero");
                }
        else if ((llq && mDNSIPPortIsZero(llq->ExternalPort)) || (tun && mDNSIPPortIsZero(tun->ExternalPort)))
                {
                status = mStatus_NATTraversal;
                mDNS_snprintf(buffer, sizeof(buffer), "Unable to obtain NAT port mapping from router");
                }
        else
                {
                status = UpdateRRStatus(m, buffer, sizeof(buffer), info);
                if (status == mStatus_NoError)  
                        status = UpdateLLQStatus(m, buffer, sizeof(buffer), info);
                LogInfo("UpdateAutoTunnelDomainStatus:ZeroRelayAddress: Status %d, %s", status, buffer);
                }
        
        num = CFNumberCreate(NULL, kCFNumberSInt32Type, &status);
        if (!num)
                LogMsg("UpdateAutoTunnelDomainStatus: Could not create CFNumber StatusCode");
        else
                {
                CFDictionarySetValue(dict, CFSTR("StatusCode"), num);
                CFRelease(num);
                }
                
        tmp = CFStringCreateWithCString(NULL, buffer, kCFStringEncodingUTF8);
        if (!tmp)
                LogMsg("UpdateAutoTunnelDomainStatus: Could not create CFString StatusMessage");
        else
                {
                CFDictionarySetValue(dict, CFSTR("StatusMessage"), tmp);
                CFRelease(tmp);
                }

        if (!CFDictionaryContainsKey(domainStatusDict, domain) ||
            !CFEqual(dict, (CFMutableDictionaryRef)CFDictionaryGetValue(domainStatusDict, domain)))
            {
                CFDictionarySetValue(domainStatusDict, domain, dict);
                if (!m->ShutdownTime) 
                        {
                        static char statusBuf[16];
                        mDNS_snprintf(statusBuf, sizeof(statusBuf), "%d", (int)status);
                        mDNSASLLog((uuid_t *)&m->asl_uuid, "autotunnel.domainstatus", status ? "failure" : "success", statusBuf, "");
                        mDNSEReporterLog((uuid_t *)&m->asl_uuid, "autotunnel.domainstatus", status, statusBuf);
                        mDNSDynamicStoreSetConfig(kmDNSBackToMyMacConfig, mDNSNULL, domainStatusDict);
                        }
                }
                
        CFRelease(domain);
        CFRelease(dict);


        debugf("UpdateAutoTunnelDomainStatus: %s", buffer);
#endif // def NO_SECURITYFRAMEWORK
        }

// MUST be called with lock held
mDNSexport void UpdateAutoTunnelDomainStatuses(const mDNS *const m)
        {
#ifdef NO_SECURITYFRAMEWORK
        (void)m;
#else
        if (!m->mDNS_busy) LogMsg("UpdateAutoTunnelDomainStatuses: ERROR!! Lock not held");
        DomainAuthInfo* info;
        for (info = m->AuthInfoList; info; info = info->next)
                if (info->AutoTunnel && !info->deltime)
                        UpdateAutoTunnelDomainStatus(m, info);
#endif // def NO_SECURITYFRAMEWORK
        }
        
// MUST be called with lock held
mDNSlocal mDNSBool TunnelServers(mDNS *const m)
        {
        AuthRecord *r;
        for (r = m->ResourceRecords; r; r = r->next)
                if (r->resrec.rrtype == kDNSType_SRV)
                        {
                        DomainAuthInfo *AuthInfo = GetAuthInfoForName_internal(m, r->resrec.name);
                        if (AuthInfo && AuthInfo->AutoTunnel && !AuthInfo->deltime) return(mDNStrue);
                        }

        return(mDNSfalse);
        }

// MUST be called with lock held
mDNSlocal mDNSBool TunnelClients(mDNS *const m)
        {
        ClientTunnel *p;
        for (p = m->TunnelClients; p; p = p->next)
                if (p->q.ThisQInterval < 0)
                        return(mDNStrue);
        return(mDNSfalse);
        }

mDNSlocal void UpdateAnonymousRacoonConfig(mDNS *m)             // Determine whether we need racoon to accept incoming connections
        {
        DomainAuthInfo *info;
        
        for (info = m->AuthInfoList; info; info = info->next)
                if (info->AutoTunnel && !info->deltime && (!mDNSIPPortIsZero(info->AutoTunnelNAT.ExternalPort) || !mDNSIPv6AddressIsZero(m->AutoTunnelRelayAddr)))
                        break;
        
        if (info != AnonymousRacoonConfig)
                {
                AnonymousRacoonConfig = info;
                // Create or revert configuration file, and start (or SIGHUP) Racoon
                (void)mDNSConfigureServer(AnonymousRacoonConfig ? kmDNSUp : kmDNSDown, AnonymousRacoonConfig ? &AnonymousRacoonConfig->domain : mDNSNULL);
                }
        }

// Caller should hold the lock. We don't call mDNS_Register (which acquires the lock) in this function because
// sometimes the caller may already be holding the lock e.g., RegisterAutoTunnel6Record and sometimes
// not e.g., RegisterAutoTunnelServiceRecord
mDNSlocal void RegisterAutoTunnelHostRecord(mDNS *m, DomainAuthInfo *info)
        {
        mStatus err;
        mDNSBool NATProblem;

        if (!m->mDNS_busy) LogMsg("RegisterAutoTunnelHostRecord: ERROR!! Lock not held");

        // We use AutoTunnelNAT.clientContext to infer that SetupLocalAutoTunnelInterface_internal has been
        // called at least once with some Services/Records in the domain and hence it is safe to register
        // records when this function is called.
        if (!info->AutoTunnelNAT.clientContext) { LogInfo("RegisterAutoTunnelHostRecord: No services registered, not registering the record\n"); return; }

        // Are we behind a NAT with no NAT-PMP support or behind a Double NAT ? Double NATs may have
        // NAT-PMP support but it still does not provide inbound connectivity. If there is no NAT-PMP
        // support, ExternalPort is zero. If we are behind a Double NAT, then the NATResult is non-zero.

        NATProblem = mDNSIPPortIsZero(info->AutoTunnelNAT.ExternalPort) || info->AutoTunnelNAT.Result;

        if (mDNSIPv6AddressIsZero(m->AutoTunnelRelayAddr))
                {
                // If we don't have a relay address, check to see if we are behind a Double NAT or NAT with no NAT-PMP
                // support.  
                if (NATProblem)
                        {
                        LogInfo("RegisterAutoTunnelHostRecord %##s, not registering the Host Record, Neither AutoTunnel6 nor NAT is available, ClientContext %p, ExternalPort %d, NAT Result %d", info->domain.c, info->AutoTunnelNAT.clientContext, mDNSVal16(info->AutoTunnelNAT.ExternalPort), info->AutoTunnelNAT.Result);
                        return;
                        }
                }
        else
                {
                // Relay address may be non-zero but we might be going to sleep as the utun interface is not removed
                // when going to sleep. If we are awake, we don't care about the NATProblem as the relay connnection
                // is up. If we are going to sleep, we should not register the host record if we have a NAT problem.
                if (m->SleepState != SleepState_Awake && NATProblem)
                        {
                        LogInfo("RegisterAutoTunnelHostRecord %##s, not registering the Host Record, Not in awake state(%d), and some NAT Problem, ClientContext %p, ExternalPort %d, NAT Result %d", info->domain.c, m->SleepState, info->AutoTunnelNAT.clientContext, mDNSVal16(info->AutoTunnelNAT.ExternalPort), info->AutoTunnelNAT.Result);
                        return;
                        }
                }

        // Note:
        //
        // We use zero Requested port to infer that we should not be calling Register anymore as it might
        // be shutdown or the DomainAuthInfo is going away.
        //
        // We can use a different set of state variables to track the above as the records registered in
        // this function is not dependent on NAT traversal info. For the sake of simplicity, we just
        // reuse the NAT variables.

        // Set up our address record for the internal tunnel address
        // (User-visible user-friendly host name, used as target in AutoTunnel SRV records)
        if (!mDNSIPPortIsZero(info->AutoTunnelNAT.RequestedPort) && info->AutoTunnelHostRecord.resrec.RecordType == kDNSRecordTypeUnregistered)
                {
                info->AutoTunnelHostRecord.namestorage.c[0] = 0;
                AppendDomainLabel(&info->AutoTunnelHostRecord.namestorage, &m->hostlabel);
                AppendDomainName (&info->AutoTunnelHostRecord.namestorage, &info->domain);
                info->AutoTunnelHostRecord.resrec.rdata->u.ipv6 = m->AutoTunnelHostAddr;
                info->AutoTunnelHostRecord.resrec.RecordType = kDNSRecordTypeKnownUnique;

                err = mDNS_Register_internal(m, &info->AutoTunnelHostRecord);

                if (err) LogMsg("RegisterAutoTunnelHostRecord error %d registering AutoTunnelHostRecord %##s", err, info->AutoTunnelHostRecord.namestorage.c);
                else
                        {
                        // Make sure we trigger the registration of all SRV records in regState_NoTarget again
                        m->NextSRVUpdate = NonZeroTime(m->timenow);
                        LogInfo("RegisterAutoTunnelHostRecord registering AutoTunnelHostRecord %##s", info->AutoTunnelHostRecord.namestorage.c);
                        }
                }
        else LogInfo("RegisterAutoTunnelHostRecord: Not registering Context %p Port %d Type %d", info->AutoTunnelNAT.clientContext, mDNSVal16(info->AutoTunnelNAT.RequestedPort), info->AutoTunnelHostRecord.resrec.RecordType);
        }

mDNSlocal void DeregisterAutoTunnelHostRecord(mDNS *m, DomainAuthInfo *info)
        {
        LogInfo("DeregisterAutoTunnelHostRecord %##s", info->domain.c);

        // Don't deregister if we have the AutoTunnel6 or AutoTunnelService records are registered.
        // They indicate that BTMM is working
        if (info->AutoTunnel6Record.resrec.RecordType > kDNSRecordTypeDeregistering ||
            info->AutoTunnelService.resrec.RecordType > kDNSRecordTypeDeregistering)
                {
                LogInfo("DeregisterAutoTunnelHostRecord %##s, not deregistering the Host Record AutoTunnel6 RecordType:%d AutoTunnel RecordType: %d", info->domain.c,
                        info->AutoTunnel6Record.resrec.RecordType, info->AutoTunnelService.resrec.RecordType);
                return;
                }

        if (info->AutoTunnelHostRecord.resrec.RecordType > kDNSRecordTypeDeregistering)
                {
                mStatus err = mDNS_Deregister(m, &info->AutoTunnelHostRecord);
                if (err)
                        {
                        info->AutoTunnelHostRecord.resrec.RecordType = kDNSRecordTypeUnregistered;
                        LogMsg("DeregisterAutoTunnelHostRecord error %d deregistering AutoTunnelHostRecord %##s", err, info->AutoTunnelHostRecord.namestorage.c);
                        }
                else LogInfo("DeregisterAutoTunnelHostRecord: Deregistered AutoTunnel Host Record");
                }
        else LogInfo("DeregisterAutoTunnelHostRecord: Not deregistering Host Record state:%d", info->AutoTunnelHostRecord.resrec.RecordType);
        }

mDNSlocal void RegisterAutoTunnelServiceRecords(mDNS *m, DomainAuthInfo *info)
        {
        mStatus err;

        //if (m->mDNS_busy) LogMsg("RegisterAutoTunnelServiceRecords: ERROR!! Lock already held");

        if (info->AutoTunnelNAT.clientContext && !info->AutoTunnelNAT.Result && !mDNSIPPortIsZero(info->AutoTunnelNAT.ExternalPort) && info->AutoTunnelTarget.resrec.RecordType == kDNSRecordTypeUnregistered)
                {
                LogInfo("RegisterAutoTunnelServiceRecords %##s (%#s)", info->domain.c, m->hostlabel.c);

                // 1. Set up our address record for the external tunnel address
                // (Constructed name, not generally user-visible, used as target in IKE tunnel's SRV record)
                info->AutoTunnelTarget.namestorage.c[0] = 0;
                AppendDomainLabel(&info->AutoTunnelTarget.namestorage, &m->AutoTunnelLabel);
                AppendDomainName (&info->AutoTunnelTarget.namestorage, &info->domain);
                info->AutoTunnelTarget.resrec.rdata->u.ipv4 = info->AutoTunnelNAT.ExternalAddress;
                info->AutoTunnelTarget.resrec.RecordType = kDNSRecordTypeKnownUnique;

                err = mDNS_Register(m, &info->AutoTunnelTarget);
                if (err) LogMsg("RegisterAutoTunnelServiceRecords error %d registering AutoTunnelTarget %##s", err, info->AutoTunnelTarget.namestorage.c);
                else LogInfo("RegisterAutoTunnelServiceRecords registering AutoTunnelTarget %##s", info->AutoTunnelTarget.namestorage.c);

                }

        if (info->AutoTunnelNAT.clientContext && !info->AutoTunnelNAT.Result && !mDNSIPPortIsZero(info->AutoTunnelNAT.ExternalPort) && info->AutoTunnelService.resrec.RecordType == kDNSRecordTypeUnregistered)
                {
                // 2. Set up IKE tunnel's SRV record: "AutoTunnelHostRecord SRV 0 0 port AutoTunnelTarget"
                AssignDomainName (&info->AutoTunnelService.namestorage, (const domainname*) "\x0B" "_autotunnel" "\x04" "_udp");
                AppendDomainLabel(&info->AutoTunnelService.namestorage, &m->hostlabel);
                AppendDomainName (&info->AutoTunnelService.namestorage, &info->domain);
                info->AutoTunnelService.resrec.rdata->u.srv.priority = 0;
                info->AutoTunnelService.resrec.rdata->u.srv.weight   = 0;
                info->AutoTunnelService.resrec.rdata->u.srv.port     = info->AutoTunnelNAT.ExternalPort;
                AssignDomainName(&info->AutoTunnelService.resrec.rdata->u.srv.target, &info->AutoTunnelTarget.namestorage);
                info->AutoTunnelService.resrec.RecordType = kDNSRecordTypeKnownUnique;
                err = mDNS_Register(m, &info->AutoTunnelService);
                if (err) LogMsg("RegisterAutoTunnelServiceRecords error %d registering AutoTunnelService %##s", err, info->AutoTunnelService.namestorage.c);
                else LogInfo("RegisterAutoTunnelServiceRecords registering AutoTunnelService %##s", info->AutoTunnelService.namestorage.c);

                LogInfo("AutoTunnel server listening for connections on %##s[%.4a]:%d:%##s[%.16a]",
                        info->AutoTunnelTarget.namestorage.c,     &m->AdvertisedV4.ip.v4, mDNSVal16(info->AutoTunnelNAT.IntPort),
                        info->AutoTunnelHostRecord.namestorage.c, &m->AutoTunnelHostAddr);
                }
        mDNS_Lock(m);
        RegisterAutoTunnelHostRecord(m, info);
        mDNS_Unlock(m);
        }

mDNSlocal void DeregisterAutoTunnelServiceRecords(mDNS *m, DomainAuthInfo *info)
        {
        LogInfo("DeregisterAutoTunnelServiceRecords %##s", info->domain.c);
        if (info->AutoTunnelTarget.resrec.RecordType > kDNSRecordTypeDeregistering)
                {
                mStatus err = mDNS_Deregister(m, &info->AutoTunnelTarget);
                if (err)
                        {
                        info->AutoTunnelTarget.resrec.RecordType = kDNSRecordTypeUnregistered;
                        LogMsg("DeregisterAutoTunnelServiceRecords error %d deregistering AutoTunnelTarget %##s", err, info->AutoTunnelTarget.namestorage.c);
                        }
                else LogInfo("DeregisterAutoTunnelServiceRecords: Deregistered AutoTunnel Target  Record");

                }
        else LogInfo("DeregisterAutoTunnelServiceRecords: Not deregistering Target record state:%d", info->AutoTunnelService.resrec.RecordType);

        if (info->AutoTunnelService.resrec.RecordType > kDNSRecordTypeDeregistering)
                {
                mStatus err = mDNS_Deregister(m, &info->AutoTunnelService);
                if (err)
                        {
                        info->AutoTunnelService.resrec.RecordType = kDNSRecordTypeUnregistered;
                        LogMsg("DeregisterAutoTunnelServiceRecords error %d deregistering AutoTunnelService %##s", err, info->AutoTunnelService.namestorage.c);
                        }
                else LogInfo("DeregisterAutoTunnelServiceRecords: Deregistered AutoTunnel Service Record");

                }
        else LogInfo("DeregisterAutoTunnelServiceRecords: Not deregistering service records state:%d", info->AutoTunnelService.resrec.RecordType);

        DeregisterAutoTunnelHostRecord(m, info);
        }

// Caller should hold the lock. We don't call mDNS_Register (which acquires the lock) in this function because
// sometimes the caller may already be holding the lock e.g., SetupLocalAutoTunnelInterface_internal and sometimes
// not e.g., AutoTunnelHostNameChanged
mDNSlocal void RegisterAutoTunnelDevInfoRecord(mDNS *m, DomainAuthInfo *info)
        {
        mStatus err;

        if (!m->mDNS_busy) LogMsg("RegisterAutoTunnelDevInfoRecord: Lock not held");
        // Note:
        // a. We use AutoTunnelNAT.clientContext to infer that SetupLocalAutoTunnelInterface_internal has been
        //    called at least once with some Services/Records in the domain and hence it is safe to register
        //    records when this function is called.
        //
        // b. We use zero Requested port to infer that we should not be calling Register anymore as it might
        //    be shutdown or the DomainAuthInfo is going away.
        //
        // We can use a different set of state variables to track the above as the records registered in
        // this function is not dependent on NAT traversal info. For the sake of simplicity, we just
        // reuse the NAT variables.

        // Set up device info record
        if (info->AutoTunnelNAT.clientContext && !mDNSIPPortIsZero(info->AutoTunnelNAT.RequestedPort) && info->AutoTunnelDeviceInfo.resrec.RecordType == kDNSRecordTypeUnregistered)
                {
                ConstructServiceName(&info->AutoTunnelDeviceInfo.namestorage, &m->nicelabel, &DeviceInfoName, &info->domain);
                mDNSu8 len = m->HIHardware.c[0] < 255 - 6 ? m->HIHardware.c[0] : 255 - 6;
                mDNSPlatformMemCopy(info->AutoTunnelDeviceInfo.resrec.rdata->u.data + 1, "model=", 6);
                mDNSPlatformMemCopy(info->AutoTunnelDeviceInfo.resrec.rdata->u.data + 7, m->HIHardware.c + 1, len);
                info->AutoTunnelDeviceInfo.resrec.rdata->u.data[0] = 6 + len;   // "model=" plus the device string
                info->AutoTunnelDeviceInfo.resrec.rdlength         = 7 + len;   // One extra for the length byte at the start of the string
                info->AutoTunnelDeviceInfo.resrec.RecordType = kDNSRecordTypeKnownUnique;

                err = mDNS_Register_internal(m, &info->AutoTunnelDeviceInfo);
                if (err) LogMsg("RegisterAutoTunnelDevInfoRecord error %d registering AutoTunnelDeviceInfo %##s", err, info->AutoTunnelDeviceInfo.namestorage.c);
                else LogInfo("RegisterAutoTunnelDevInfoRecord registering AutoTunnelDeviceInfo %##s", info->AutoTunnelDeviceInfo.namestorage.c);
                }
        }

#ifndef NO_SECURITYFRAMEWORK
mDNSlocal void DeregisterAutoTunnelDevInfoRecord(mDNS *m, DomainAuthInfo *info)
        {
        LogInfo("DeregisterAutoTunnelDevInfoRecord %##s", info->domain.c);

        if (info->AutoTunnelDeviceInfo.resrec.RecordType > kDNSRecordTypeDeregistering)
                {
                mStatus err = mDNS_Deregister(m, &info->AutoTunnelDeviceInfo);
                if (err)
                        {
                        info->AutoTunnelDeviceInfo.resrec.RecordType = kDNSRecordTypeUnregistered;
                        LogMsg("DeregisterAutoTunnelDevInfoRecord error %d deregistering AutoTunnelDeviceInfo %##s", err, info->AutoTunnelDeviceInfo.namestorage.c);
                        }
                else LogInfo("DeregisterAutoTunnelDevInfoRecord: Deregistered AutoTunnel Device Info");
                }
        else LogInfo("DeregisterAutoTunnelDevInfoRecord: Not deregistering DeviceInfo  Record state:%d", info->AutoTunnelDeviceInfo.resrec.RecordType);
        }
#endif


// Caller should hold the lock. We don't call mDNS_Register (which acquires the lock) in this function because
// sometimes the caller may already be holding the lock e.g., SetupLocalAutoTunnelInterface_internal and sometimes
// not e.g., AutoTunnelHostNameChanged
mDNSlocal void RegisterAutoTunnel6Record(mDNS *m, DomainAuthInfo *info)
        {
        mStatus err;

        if (!m->mDNS_busy) LogMsg("RegisterAutoTunnel6Record: ERROR!! Lock not held");

        // We deregister the AutoTunnel6Record during sleep and come back here (AutoTunnelRecordCallback) to
        // register the address if needed. During that time, we might get a network change event which finds
        // that the utun interface exists and tries to register the AutoTunnel6Record which should be stopped.
        // Also the RelayAddress is reinitialized during that process which in turn causes the AutoTunnelRecordCallback
        // to re-register again. To stop these, we check for the SleepState and register only if we are awake.
        if (m->SleepState != SleepState_Awake)
                {
                LogInfo("RegisterAutoTunnel6Record: Not in awake state, SleepState %d", m->SleepState);
                return;
                }

        // if disabled administratively, don't register
        // if disabled administratively, don't register
        if (!m->RegisterAutoTunnel6 || DisableInboundRelayConnection)
                {
                LogInfo("RegisterAutoTunnel6Record: registration Disabled RegisterAutoTunnel6 %d, DisableInbound %d",
                        m->RegisterAutoTunnel6, DisableInboundRelayConnection);
                return;
                }
        //
        // If we have a valid Relay address, we need to register it now. When we got a valid address, we may not
        // have registered it because it was waiting for at least one service to become active in the BTMM domain.
        // During network change event, we might be called multiple times while the "Connectivity" key did not
        // change, so check to see if the value has changed. This can also be zero when we are deregistering and
        // getting called from the AutoTunnelRecordCallback

        if (mDNSIPv6AddressIsZero(m->AutoTunnelRelayAddr))
                {
                LogInfo("RegisterAutoTunnel6Record: Relay address is zero, not registering");
                return;
                }

        if ((info->AutoTunnel6Record.resrec.RecordType > kDNSRecordTypeDeregistering) &&
                (mDNSSameIPv6Address(info->AutoTunnel6Record.resrec.rdata->u.ipv6, m->AutoTunnelRelayAddr)))
                {
                LogInfo("RegisterAutoTunnel6Record: Relay address %.16a same, not registering", &m->AutoTunnelRelayAddr);
                return;
                }

        // Note:
        // a. We use AutoTunnelNAT.clientContext to infer that SetupLocalAutoTunnelInterface_internal has been
        //    called at least once with some Services/Records in the domain and hence it is safe to register
        //    records when this function is called.
        //
        // b. We use zero Requested port to infer that we should not be calling Register anymore as it might
        //    be shutdown or the DomainAuthInfo is going away.
        //
        // We can use a different set of state variables to track the above as the records registered in
        // this function is not dependent on NAT traversal info. For the sake of simplicity, we just
        // reuse the NAT variables.

        if (info->AutoTunnelNAT.clientContext && !mDNSIPPortIsZero(info->AutoTunnelNAT.RequestedPort) &&
            info->AutoTunnel6Record.resrec.RecordType == kDNSRecordTypeUnregistered)
                {
                AssignDomainName (&info->AutoTunnel6Record.namestorage, (const domainname*) "\x0C" "_autotunnel6");
                AppendDomainLabel(&info->AutoTunnel6Record.namestorage, &m->hostlabel);
                AppendDomainName (&info->AutoTunnel6Record.namestorage, &info->domain);
                info->AutoTunnel6Record.resrec.rdata->u.ipv6 = m->AutoTunnelRelayAddr;
                info->AutoTunnel6Record.resrec.RecordType = kDNSRecordTypeKnownUnique;

                err = mDNS_Register_internal(m, &info->AutoTunnel6Record);
                if (err) LogMsg("RegisterAutoTunnel6Record error %d registering AutoTunnel6 Record %##s", err, info->AutoTunnel6Record.namestorage.c);
                else LogInfo("RegisterAutoTunnel6Record registering AutoTunnel6 Record %##s", info->AutoTunnel6Record.namestorage.c);

                LogInfo("AutoTunnel6 server listening for connections on %##s[%.16a] :%##s[%.16a]",
                        info->AutoTunnel6Record.namestorage.c,     &m->AutoTunnelRelayAddr,
                        info->AutoTunnelHostRecord.namestorage.c, &m->AutoTunnelHostAddr);

                } else {LogInfo("RegisterAutoTunnel6Record: client context %p, RequestedPort %d, Address %.16a, record type %d", info->AutoTunnelNAT.clientContext, info->AutoTunnelNAT.RequestedPort, &m->AutoTunnelRelayAddr, info->AutoTunnel6Record.resrec.RecordType);}

        RegisterAutoTunnelHostRecord(m, info);
        // When the AutoTunnel6 record comes up, we need to kick racoon and update the status.
        // If we had a port mapping, we would have done it in RegisterAutoTunnelServiceRecords.
        // If we don't have a port mapping, we need to do it here.
        UpdateAnonymousRacoonConfig(m);         // Determine whether we need racoon to accept incoming connections
        UpdateAutoTunnelDomainStatus(m, info);
        }

mDNSlocal void DeregisterAutoTunnel6Record(mDNS *m, DomainAuthInfo *info)
        {
        LogInfo("DeregisterAutoTunnel6Record %##s", info->domain.c);

        if (info->AutoTunnel6Record.resrec.RecordType > kDNSRecordTypeDeregistering)
                {
                mStatus err = mDNS_Deregister(m, &info->AutoTunnel6Record);
                if (err)
                        {
                        info->AutoTunnel6Record.resrec.RecordType = kDNSRecordTypeUnregistered;
                        info->AutoTunnel6Record.resrec.rdata->u.ipv6 = zerov6Addr;
                        LogMsg("DeregisterAutoTunnel6Record error %d deregistering AutoTunnel6Record %##s", err, info->AutoTunnel6Record.namestorage.c);
                        }
                else LogInfo("DeregisterAutoTunnel6Record: Deregistered AutoTunnel6 Record");
                }
        else LogInfo("DeregisterAutoTunnel6Record: Not deregistering AuoTunnel6 record state:%d", info->AutoTunnel6Record.resrec.RecordType);

        DeregisterAutoTunnelHostRecord(m, info);
        // UpdateAutoTunnelDomainStatus is careful enough not to turn it on if we don't have
        // a external port mapping. Otherwise, it will be turned off.
        mDNS_Lock(m);
        UpdateAutoTunnelDomainStatus(m, info);
        mDNS_Unlock(m);
        }

mDNSlocal void AutoTunnelRecordCallback(mDNS *const m, AuthRecord *const rr, mStatus result)
        {
        DomainAuthInfo *info = (DomainAuthInfo *)rr->RecordContext;
        if (result == mStatus_MemFree)
                {
                LogInfo("AutoTunnelRecordCallback MemFree %s", ARDisplayString(m, rr));
                // Reset the host record namestorage to force high-level PTR/SRV/TXT to deregister
                if (rr == &info->AutoTunnelHostRecord)
                        {
                        rr->namestorage.c[0] = 0;
                        m->NextSRVUpdate = NonZeroTime(m->timenow);
                        LogInfo("AutoTunnelRecordCallback: NextSRVUpdate in %d %d", m->NextSRVUpdate - m->timenow, m->timenow);
                        }
                if (m->ShutdownTime) {LogInfo("AutoTunnelRecordCallback: Shutdown, returning");return;}
                if (rr == &info->AutoTunnelHostRecord)
                        {
                        LogInfo("AutoTunnelRecordCallback: calling RegisterAutoTunnelHostRecord");
                        RegisterAutoTunnelHostRecord(m,info);
                        }
                else if (rr == &info->AutoTunnelDeviceInfo)
                        {
                        LogInfo("AutoTunnelRecordCallback: Calling RegisterAutoTunnelDevInfoRecord");
                        RegisterAutoTunnelDevInfoRecord(m,info);
                        }
                else if (rr == &info->AutoTunnelService || rr == &info->AutoTunnelTarget)
                        {
                        LogInfo("AutoTunnelRecordCallback: Calling RegisterAutoTunnelServiceRecords");
                        RegisterAutoTunnelServiceRecords(m,info);
                        }
                else if (rr == &info->AutoTunnel6Record)
                        {
                        LogInfo("AutoTunnelRecordCallback: Calling RegisterAutoTunnel6Record");
                        info->AutoTunnel6Record.resrec.rdata->u.ipv6 = zerov6Addr;
                        RegisterAutoTunnel6Record(m,info);
                        }
                }
        }

#ifndef NO_SECURITYFRAMEWORK
mDNSlocal void AutoTunnelDeleteAuthInfoState(mDNS *m, DomainAuthInfo *info)
        {
        LogInfo("AutoTunnelDeleteAuthInfoState: Cleaning up state releated to Domain AuthInfo %##s", info->domain.c);

        m->NextSRVUpdate = NonZeroTime(m->timenow);
        DeregisterAutoTunnelDevInfoRecord(m, info);
        DeregisterAutoTunnelServiceRecords(m, info);
        DeregisterAutoTunnel6Record(m, info);
        UpdateAnonymousRacoonConfig(m);         // Determine whether we need racoon to accept incoming connections
        UpdateAutoTunnelDomainStatus(m, info);
        }
#endif // ndef NO_SECURITYFRAMEWORK

mDNSlocal void AutoTunnelNATCallback(mDNS *m, NATTraversalInfo *n)
        {
        DomainAuthInfo *info = (DomainAuthInfo *)n->clientContext;
        LogInfo("AutoTunnelNATCallback Result %d %.4a Internal %d External %d %#s.%##s",
                n->Result, &n->ExternalAddress, mDNSVal16(n->IntPort), mDNSVal16(n->ExternalPort), m->hostlabel.c, info->domain.c);

        m->NextSRVUpdate = NonZeroTime(m->timenow);
        LogInfo("AutoTunnelNATCallback: NextSRVUpdate in %d %d", m->NextSRVUpdate - m->timenow, m->timenow);

        DeregisterAutoTunnelServiceRecords(m, info);
        RegisterAutoTunnelServiceRecords(m, info);
        
        UpdateAnonymousRacoonConfig(m);         // Determine whether we need racoon to accept incoming connections

        UpdateAutoTunnelDomainStatus(m, (DomainAuthInfo *)n->clientContext);
        }

mDNSlocal void AbortDeregistration(mDNS *const m, AuthRecord *rr)
        {
        if (rr->resrec.RecordType == kDNSRecordTypeDeregistering)
                {
                LogInfo("Aborting deregistration of %s", ARDisplayString(m, rr));
                CompleteDeregistration(m, rr);
                }
        else if (rr->resrec.RecordType != kDNSRecordTypeUnregistered)
                LogMsg("AbortDeregistration ERROR RecordType %02X for %s", ARDisplayString(m, rr));
        }

mDNSlocal void AutoTunnelHostNameChanged(mDNS *m, DomainAuthInfo *info)
        {
        LogInfo("AutoTunnelHostNameChanged %#s.%##s", m->hostlabel.c, info->domain.c);

        DeregisterAutoTunnelDevInfoRecord(m, info);
        DeregisterAutoTunnelServiceRecords(m, info);
        DeregisterAutoTunnel6Record(m, info);
        RegisterAutoTunnelServiceRecords(m, info);

        mDNS_Lock(m);
        RegisterAutoTunnelDevInfoRecord(m, info);
        RegisterAutoTunnel6Record(m, info);
        m->NextSRVUpdate = NonZeroTime(m->timenow);
        mDNS_Unlock(m);
        }

mDNSlocal void SetupLocalAutoTunnel6Records(mDNS *const m, DomainAuthInfo *info)
        {
        AbortDeregistration(m, &info->AutoTunnelDeviceInfo);
        AbortDeregistration(m, &info->AutoTunnel6Record);

        // When the BTMM is turned on/off too quickly, following things happen.
        //
        // 1. Turning off BTMM triggers deregistration of the DevInfo/AutoTunnel6 etc. records
        // 2. While (1) is in progress, the BTMM is turned on
        //
        // At step (2), mDNS_SetSecretForDomain clears info->deltime indicating that the domain is valid
        // while we have not processed the turning off BTMM completely. Hence, we end up calling this
        // function to re-register the records. AbortDeregistration above aborts the Deregistration as the
        // records are still in Deregistering state and in AutoTunnelRecordCallback we end up registering
        // again. So, we have to be careful below to not call mDNS_SetupResourceRecord again which will
        // reset the state to Unregistered and registering again will lead to error as it is registered
        // and already in the list. Hence, register below only if needed.

        if (info->AutoTunnelDeviceInfo.resrec.RecordType != kDNSRecordTypeUnregistered ||
            info->AutoTunnel6Record.resrec.RecordType != kDNSRecordTypeUnregistered)
                {
                LogInfo("SetupLocalAutoTunnel6Records: AutoTunnel Records not in Unregistered state: Device: %d, AutoTunnel6:%d",
                        info->AutoTunnelDeviceInfo.resrec.RecordType, info->AutoTunnel6Record.resrec.RecordType);
                }

        if (info->AutoTunnelDeviceInfo.resrec.RecordType == kDNSRecordTypeUnregistered)
                {
                mDNS_SetupResourceRecord(&info->AutoTunnelDeviceInfo, mDNSNULL, mDNSInterface_Any, kDNSType_TXT,  kStandardTTL, kDNSRecordTypeUnregistered, AutoTunnelRecordCallback, info);
                RegisterAutoTunnelDevInfoRecord(m, info);
                }
        if (info->AutoTunnel6Record.resrec.RecordType == kDNSRecordTypeUnregistered)
                {
                mDNS_SetupResourceRecord(&info->AutoTunnel6Record, mDNSNULL, mDNSInterface_Any, kDNSType_AAAA, kHostNameTTL, kDNSRecordTypeUnregistered, AutoTunnelRecordCallback, info);
                RegisterAutoTunnel6Record(m, info);
                }

        UpdateAnonymousRacoonConfig(m);         // Determine whether we need racoon to accept incoming connections
        
        UpdateAutoTunnelDomainStatus(m, info);
        m->NextSRVUpdate = NonZeroTime(m->timenow);
        }

// Before SetupLocalAutoTunnelInterface_internal is called,
// m->AutoTunnelHostAddr.b[0] must be non-zero, and there must be at least one TunnelClient or TunnelServer
// Must be called with the lock held
mDNSexport void SetupLocalAutoTunnelInterface_internal(mDNS *const m, mDNSBool servicesStarting)
        {
        // 1. Configure the local IPv6 ULA BTMM address
        if (!m->AutoTunnelHostAddrActive)
                {
                m->AutoTunnelHostAddrActive = mDNStrue;
                LogInfo("SetupLocalAutoTunnelInterface_internal: Setting up AutoTunnel address %.16a", &m->AutoTunnelHostAddr);
                (void)mDNSAutoTunnelInterfaceUpDown(kmDNSUp, m->AutoTunnelHostAddr.b);
                }

        // 2. If we have at least one server (pending) listening, publish our records
        // The services may not be in the list when it is first trying to resolve the target of the SRV record.
        // servicesStarting is an indication of that. Use that instead of looking up in the list of Services/Records.
        if (servicesStarting || TunnelServers(m))
                {
                DomainAuthInfo *info;
                for (info = m->AuthInfoList; info; info = info->next)
                        {
                        if (info->AutoTunnel && !info->deltime && !info->AutoTunnelNAT.clientContext)
                                {
                                // If we just resurrected a DomainAuthInfo that is still deregistering, we need to abort the
                                // deregistration process before re-using the AuthRecord memory
                                //
                                // Note: We don't need the same caution as in SetupLocalAutoTunnel6Records (see the comments there)
                                // as AutoTunnelRecordCallback (called as a result of AbortDeregistration) will not end up registering
                                // the records because clientContext is still NULL

                                AbortDeregistration(m, &info->AutoTunnelTarget);
                                AbortDeregistration(m, &info->AutoTunnelService);
                                AbortDeregistration(m, &info->AutoTunnelHostRecord);

                                mDNS_SetupResourceRecord(&info->AutoTunnelTarget,     mDNSNULL, mDNSInterface_Any, kDNSType_A,    kHostNameTTL,
                                        kDNSRecordTypeUnregistered, AutoTunnelRecordCallback, info);
                                mDNS_SetupResourceRecord(&info->AutoTunnelService,    mDNSNULL, mDNSInterface_Any, kDNSType_SRV,  kHostNameTTL,
                                        kDNSRecordTypeUnregistered, AutoTunnelRecordCallback, info);
                                mDNS_SetupResourceRecord(&info->AutoTunnelHostRecord, mDNSNULL, mDNSInterface_Any, kDNSType_AAAA, kHostNameTTL,
                                        kDNSRecordTypeUnregistered, AutoTunnelRecordCallback, info);

                                // Try to get a NAT port mapping for the AutoTunnelService
                                info->AutoTunnelNAT.clientCallback   = AutoTunnelNATCallback;
                                info->AutoTunnelNAT.clientContext    = info;
                                info->AutoTunnelNAT.Protocol         = NATOp_MapUDP;
                                info->AutoTunnelNAT.IntPort          = IPSECPort;
                                info->AutoTunnelNAT.RequestedPort    = IPSECPort;
                                info->AutoTunnelNAT.NATLease         = 0;
                                mStatus err = mDNS_StartNATOperation_internal(m, &info->AutoTunnelNAT);
                                if (err) LogMsg("SetupLocalAutoTunnelInterface_internal: error %d starting NAT mapping", err);

                                // Register the records that can be done without communicating with the NAT
                                //
                                // Note: This should be done after we setup the AutoTunnelNAT information
                                // as some of the fields in that structure are used to infer other information
                                // e.g., is it okay to register now ?

                                SetupLocalAutoTunnel6Records(m, info);

                                }
                        }
                }
        }

mDNSlocal mStatus AutoTunnelSetKeys(ClientTunnel *tun, mDNSBool AddNew)
        {
        mDNSv6Addr loc_outer6;
        mDNSv6Addr rmt_outer6;

        // When we are tunneling over IPv6 Relay address, the port number is zero
        if (mDNSIPPortIsZero(tun->rmt_outer_port))
                {
                loc_outer6 = tun->loc_outer6;
                rmt_outer6 = tun->rmt_outer6;
                }
        else
                {
                loc_outer6 = zerov6Addr;
                loc_outer6.b[0] = tun->loc_outer.b[0];
                loc_outer6.b[1] = tun->loc_outer.b[1];
                loc_outer6.b[2] = tun->loc_outer.b[2];
                loc_outer6.b[3] = tun->loc_outer.b[3];

                rmt_outer6 = zerov6Addr;
                rmt_outer6.b[0] = tun->rmt_outer.b[0];
                rmt_outer6.b[1] = tun->rmt_outer.b[1];
                rmt_outer6.b[2] = tun->rmt_outer.b[2];
                rmt_outer6.b[3] = tun->rmt_outer.b[3];
                }

        return(mDNSAutoTunnelSetKeys(AddNew ? kmDNSAutoTunnelSetKeysReplace : kmDNSAutoTunnelSetKeysDelete, tun->loc_inner.b, loc_outer6.b, kRacoonPort, tun->rmt_inner.b, rmt_outer6.b, mDNSVal16(tun->rmt_outer_port), SkipLeadingLabels(&tun->dstname, 1)));
        }

// If the EUI-64 part of the IPv6 ULA matches, then that means the two addresses point to the same machine
#define mDNSSameClientTunnel(A,B) ((A)->l[2] == (B)->l[2] && (A)->l[3] == (B)->l[3])

mDNSlocal void ReissueBlockedQuestionWithType(mDNS *const m, domainname *d, mDNSBool success, mDNSu16 qtype)
        {
        DNSQuestion *q = m->Questions;
        while (q)
                {
                if (q->NoAnswer == NoAnswer_Suspended && q->qtype == qtype && q->AuthInfo && q->AuthInfo->AutoTunnel && SameDomainName(&q->qname, d))
                        {
                        LogInfo("Restart %##s (%s)", q->qname.c, DNSTypeName(q->qtype));
                        mDNSQuestionCallback *tmp = q->QuestionCallback;
                        q->QuestionCallback = AutoTunnelCallback;       // Set QuestionCallback to suppress another call back to AddNewClientTunnel
                        mDNS_StopQuery(m, q);
                        mDNS_StartQuery(m, q);
                        q->QuestionCallback = tmp;                                      // Restore QuestionCallback back to the real value
                        if (!success) q->NoAnswer = NoAnswer_Fail;
                        // When we call mDNS_StopQuery, it's possible for other subordinate questions like the GetZoneData query to be cancelled too.
                        // In general we have to assume that the question list might have changed in arbitrary ways.
                        // This code is itself called from a question callback, so the m->CurrentQuestion mechanism is
                        // already in use. The safest solution is just to go back to the start of the list and start again.
                        // In principle this sounds like an n^2 algorithm, but in practice we almost always activate
                        // just one suspended question, so it's really a 2n algorithm.
                        q = m->Questions;
                        }
                else
                        q = q->next;
                }
        }

mDNSlocal void ReissueBlockedQuestions(mDNS *const m, domainname *d, mDNSBool success)
        {
        // 1. We deliberately restart AAAA queries before A queries, because in the common case where a BTTM host has
        //    a v6 address but no v4 address, we prefer the caller to get the positive AAAA response before the A NXDOMAIN.
        // 2. In the case of AAAA queries, if our tunnel setup failed, then we return a deliberate failure indication to the caller --
        //    even if the name does have a valid AAAA record, we don't want clients trying to connect to it without a properly encrypted tunnel.
        // 3. For A queries we never fabricate failures -- if a BTTM service is really using raw IPv4, then it doesn't need the IPv6 tunnel.
        ReissueBlockedQuestionWithType(m, d, success, kDNSType_AAAA);
        ReissueBlockedQuestionWithType(m, d, mDNStrue, kDNSType_A);
        }

mDNSlocal void UnlinkAndReissueBlockedQuestions(mDNS *const m, ClientTunnel *tun, mDNSBool success)
        {
        ClientTunnel **p = &m->TunnelClients;
        while (*p != tun && *p) p = &(*p)->next;
        if (*p) *p = tun->next;
        ReissueBlockedQuestions(m, &tun->dstname, success);
        LogInfo("UnlinkAndReissueBlockedQuestions: Disposing ClientTunnel %p", tun);
        freeL("ClientTunnel", tun);
        }

mDNSlocal mDNSBool TunnelClientDeleteMatching(mDNS *const m, ClientTunnel *tun, mDNSBool v6Tunnel)
        {
        ClientTunnel **p;
        mDNSBool needSetKeys = mDNStrue;

        p = &tun->next;
        while (*p)
                {
                // Is this a tunnel to the same host that we are trying to setup now?
                if (!mDNSSameClientTunnel(&(*p)->rmt_inner, &tun->rmt_inner)) p = &(*p)->next;
                else
                        {
                        ClientTunnel *old = *p;
                        if (v6Tunnel)
                                {
                                if (!mDNSIPPortIsZero(old->rmt_outer_port)) { p = &old->next; continue; }
                                LogInfo("TunnelClientDeleteMatching: Found existing IPv6 AutoTunnel for %##s %.16a", old->dstname.c, &old->rmt_inner);
                                if (old->q.ThisQInterval >= 0)
                                        {
                                        LogInfo("TunnelClientDeleteMatching: Stopping query on IPv6 AutoTunnel for %##s %.16a", old->dstname.c, &old->rmt_inner);
                                        mDNS_StopQuery(m, &old->q);
                                        }
                                else if (!mDNSSameIPv6Address((*p)->rmt_inner, tun->rmt_inner) ||
                                                !mDNSSameIPv6Address(old->loc_inner, tun->loc_inner)   ||
                                                !mDNSSameIPv6Address(old->loc_outer6, tun->loc_outer6) ||
                                                !mDNSSameIPv6Address(old->rmt_outer6, tun->rmt_outer6))
                                        {
                                        // Delete the old tunnel if the current tunnel to the same host does not have the same ULA or
                                        // the other parameters of the tunnel are different
                                        LogInfo("TunnelClientDeleteMatching: Deleting existing IPv6 AutoTunnel for %##s %.16a", old->dstname.c, &old->rmt_inner);
                                        AutoTunnelSetKeys(old, mDNSfalse);
                                        }
                                else
                                        {
                                        // Reusing the existing tunnel means that we reuse the IPsec SAs and the policies. We delete the old
                                        // as "tun" and "old" are identical
                                        LogInfo("TunnelClientDeleteMatching: Reusing the existing IPv6 AutoTunnel for %##s %.16a", old->dstname.c,
                                                &old->rmt_inner);
                                        needSetKeys = mDNSfalse;
                                        }
                                }
                        else 
                                {
                                if (mDNSIPPortIsZero(old->rmt_outer_port)) { p = &old->next; continue; }
                                LogInfo("TunnelClientDeleteMatching: Found existing IPv4 AutoTunnel for %##s %.16a", old->dstname.c, &old->rmt_inner);
                                if (old->q.ThisQInterval >= 0)
                                        {
                                        LogInfo("TunnelClientDeleteMatching: Stopping query on IPv4 AutoTunnel for %##s %.16a", old->dstname.c, &old->rmt_inner);
                                        mDNS_StopQuery(m, &old->q);
                                        }
                                else if (!mDNSSameIPv6Address((*p)->rmt_inner, tun->rmt_inner) ||
                                                !mDNSSameIPv6Address(old->loc_inner, tun->loc_inner)   ||
                                                !mDNSSameIPv4Address(old->loc_outer, tun->loc_outer)   ||
                                                !mDNSSameIPv4Address(old->rmt_outer, tun->rmt_outer)   ||
                                                !mDNSSameIPPort(old->rmt_outer_port, tun->rmt_outer_port))
                                        {
                                        // Delete the old tunnel if the current tunnel to the same host does not have the same ULA or
                                        // the other parameters of the tunnel are different
                                        LogInfo("TunnelClientDeleteMatching: Deleting existing IPv4 AutoTunnel for %##s %.16a", old->dstname.c, &old->rmt_inner);
                                        AutoTunnelSetKeys(old, mDNSfalse);
                                        }
                                else
                                        {
                                        // Reusing the existing tunnel means that we reuse the IPsec SAs and the policies. We delete the old
                                        // as "tun" and "old" are identical
                                        LogInfo("TunnelClientDeleteMatching: Reusing the existing IPv4 AutoTunnel for %##s %.16a", old->dstname.c,
                                                &old->rmt_inner);
                                        needSetKeys = mDNSfalse;
                                        }
                                }

                        *p = old->next;
                        LogInfo("TunnelClientDeleteMatching: Disposing ClientTunnel %p", old);
                        freeL("ClientTunnel", old);
                        }
                }
                return needSetKeys;
        }

// v6Tunnel indicates whether to delete a tunnel whose outer header is IPv6. If false, outer IPv4
// tunnel will be deleted
mDNSlocal void TunnelClientDeleteAny(mDNS *const m, ClientTunnel *tun, mDNSBool v6Tunnel)
        {
        ClientTunnel **p;

        p = &tun->next;
        while (*p)
                {
                // If there is more than one client tunnel to the same host, delete all of them.
                // We do this by just checking against the EUI64 rather than the full address
                if (!mDNSSameClientTunnel(&(*p)->rmt_inner, &tun->rmt_inner)) p = &(*p)->next;
                else
                        {
                        ClientTunnel *old = *p;
                        if (v6Tunnel)
                                {
                                if (!mDNSIPPortIsZero(old->rmt_outer_port)) { p = &old->next; continue;}
                                LogInfo("TunnelClientDeleteAny: Found existing IPv6 AutoTunnel for %##s %.16a", old->dstname.c, &old->rmt_inner);
                                }
                        else 
                                {
                                if (mDNSIPPortIsZero(old->rmt_outer_port)) { p = &old->next; continue;}
                                LogInfo("TunnelClientDeleteAny: Found existing IPv4 AutoTunnel for %##s %.16a", old->dstname.c, &old->rmt_inner);
                                }
                        if (old->q.ThisQInterval >= 0)
                                {
                                LogInfo("TunnelClientDeleteAny: Stopping query on AutoTunnel for %##s %.16a", old->dstname.c, &old->rmt_inner);
                                mDNS_StopQuery(m, &old->q);
                                }
                        else 
                                {
                                LogInfo("TunnelClientDeleteAny: Deleting existing AutoTunnel for %##s %.16a", old->dstname.c, &old->rmt_inner);
                                AutoTunnelSetKeys(old, mDNSfalse);
                                }
                        *p = old->next;
                        LogInfo("TunnelClientDeleteAny: Disposing ClientTunnel %p", old);
                        freeL("ClientTunnel", old);
                        }
                }
        }

mDNSlocal void TunnelClientFinish(mDNS *const m, DNSQuestion *question, const ResourceRecord *const answer)
        {
        mDNSBool needSetKeys = mDNStrue;
        ClientTunnel *tun = (ClientTunnel *)question->QuestionContext;
        mDNSBool v6Tunnel = mDNSfalse;

        // If the port is zero, then we have a relay address of the peer
        if (mDNSIPPortIsZero(tun->rmt_outer_port))
                v6Tunnel = mDNStrue;

        if (v6Tunnel)
                {
                LogInfo("TunnelClientFinish: Relay address %.16a", &answer->rdata->u.ipv6);
                tun->rmt_outer6 = answer->rdata->u.ipv6;
                tun->loc_outer6 = m->AutoTunnelRelayAddr;
                }
        else
                {
                LogInfo("TunnelClientFinish: SRV target address %.4a", &answer->rdata->u.ipv4);
                tun->rmt_outer = answer->rdata->u.ipv4;
                mDNSAddr tmpDst = { mDNSAddrType_IPv4, {{{0}}} };
                tmpDst.ip.v4 = tun->rmt_outer;
                mDNSAddr tmpSrc = zeroAddr;
                mDNSPlatformSourceAddrForDest(&tmpSrc, &tmpDst);
                if (tmpSrc.type == mDNSAddrType_IPv4) tun->loc_outer = tmpSrc.ip.v4;
                else tun->loc_outer = m->AdvertisedV4.ip.v4;
                }

        question->ThisQInterval = -1;           // So we know this tunnel setup has completed
        tun->loc_inner = m->AutoTunnelHostAddr;

        // If we found a v6Relay address for our peer, delete all the v4Tunnels for our peer and
        // look for existing tunnels to see whether they have the same information for our peer.
        // If not, delete them and need to create a new tunnel. If they are same, just use the
        // same tunnel. Do the similar thing if we found a v4Tunnel end point for our peer.
        TunnelClientDeleteAny(m, tun, !v6Tunnel);
        needSetKeys = TunnelClientDeleteMatching(m, tun, v6Tunnel);

        if (needSetKeys) LogInfo("TunnelClientFinish: New %s AutoTunnel for %##s %.16a", (v6Tunnel ? "IPv6" : "IPv4"), tun->dstname.c, &tun->rmt_inner);
        else LogInfo("TunnelClientFinish: Reusing exiting %s AutoTunnel for %##s %.16a", (v6Tunnel ? "IPv6" : "IPv4"), tun->dstname.c, &tun->rmt_inner);

        if (m->AutoTunnelHostAddr.b[0]) { mDNS_Lock(m); SetupLocalAutoTunnelInterface_internal(m, mDNSfalse); mDNS_Unlock(m); };

        mStatus result = needSetKeys ? AutoTunnelSetKeys(tun, mDNStrue) : mStatus_NoError;
        static char msgbuf[32];
        mDNS_snprintf(msgbuf, sizeof(msgbuf), "Client AutoTunnel setup - %d", result);
        mDNSASLLog((uuid_t *)&m->asl_uuid, "autotunnel.config", result ? "failure" : "success", msgbuf, "");
        mDNSEReporterLog((uuid_t *)&m->asl_uuid, "autotunnel.config", result, msgbuf);
        // Kick off any questions that were held pending this tunnel setup
        ReissueBlockedQuestions(m, &tun->dstname, (result == mStatus_NoError) ? mDNStrue : mDNSfalse);
        }

mDNSexport void AutoTunnelCallback(mDNS *const m, DNSQuestion *question, const ResourceRecord *const answer, QC_result AddRecord)
        {
        ClientTunnel *tun = (ClientTunnel *)question->QuestionContext;

        LogInfo("AutoTunnelCallback tun %p AddRecord %d rdlength %d qtype %d", tun, AddRecord, answer->rdlength, question->qtype);

        if (!AddRecord) return;
        mDNS_StopQuery(m, question);

        // If we are looking up the AAAA record for _autotunnel6, don't consider it as failure.
        // The code below will look for _autotunnel._udp SRV record followed by A record
        if (tun->tc_state != TC_STATE_AAAA_PEER_RELAY && !answer->rdlength)
                {
                LogInfo("AutoTunnelCallback NXDOMAIN %##s (%s)", question->qname.c, DNSTypeName(question->qtype));
                static char msgbuf[16];
                mDNS_snprintf(msgbuf, sizeof(msgbuf), "%s lookup", DNSTypeName(question->qtype));
                mDNSASLLog((uuid_t *)&m->asl_uuid, "autotunnel.config", "failure", msgbuf, "");
                mDNSEReporterLog((uuid_t *)&m->asl_uuid, "autotunnel.config", 1, msgbuf);
                UnlinkAndReissueBlockedQuestions(m, tun, mDNSfalse);
                return;
                }

        switch (tun->tc_state)
                {
                case TC_STATE_AAAA_PEER:
                        if (question->qtype != kDNSType_AAAA)
                                {
                                LogMsg("AutoTunnelCallback: Bad question type %d in TC_STATE_AAAA_PEER", question->qtype);
                                }
                        if (mDNSSameIPv6Address(answer->rdata->u.ipv6, m->AutoTunnelHostAddr))
                                {
                                LogInfo("AutoTunnelCallback: suppressing tunnel to self %.16a", &answer->rdata->u.ipv6);
                                UnlinkAndReissueBlockedQuestions(m, tun, mDNStrue);
                                return;
                                }
                        tun->rmt_inner = answer->rdata->u.ipv6;
                        LogInfo("AutoTunnelCallback:TC_STATE_AAAA_PEER: dst host %.16a", &tun->rmt_inner);
                        if (!mDNSIPv6AddressIsZero(m->AutoTunnelRelayAddr))
                                {
                                LogInfo("AutoTunnelCallback: Looking up _autotunnel6 AAAA");
                                tun->tc_state = TC_STATE_AAAA_PEER_RELAY;
                                question->qtype = kDNSType_AAAA;
                                AssignDomainName(&question->qname, (const domainname*) "\x0C" "_autotunnel6");
                                }
                        else
                                {
                                LogInfo("AutoTunnelCallback: Looking up _autotunnel._udp SRV");
                                tun->tc_state = TC_STATE_SRV_PEER;
                                question->qtype = kDNSType_SRV;
                                AssignDomainName(&question->qname, (const domainname*) "\x0B" "_autotunnel" "\x04" "_udp");
                                }
                        AppendDomainName(&question->qname, &tun->dstname);
                        mDNS_StartQuery(m, &tun->q);
                        return;
                case TC_STATE_AAAA_PEER_RELAY:
                        if (question->qtype != kDNSType_AAAA)
                                {
                                LogMsg("AutoTunnelCallback: Bad question type %d in TC_STATE_AAAA_PEER_RELAY", question->qtype);
                                }
                        // If it failed, look for the SRV record.
                        if (!answer->rdlength)
                                {
                                LogInfo("AutoTunnelCallback: Looking up _autotunnel6 AAAA failed, trying SRV");
                                tun->tc_state = TC_STATE_SRV_PEER;
                                AssignDomainName(&question->qname, (const domainname*) "\x0B" "_autotunnel" "\x04" "_udp");
                                AppendDomainName(&question->qname, &tun->dstname);
                                question->qtype = kDNSType_SRV;
                                mDNS_StartQuery(m, &tun->q);
                                return;
                                }
                        TunnelClientFinish(m, question, answer);
                        return;
                case TC_STATE_SRV_PEER:
                        if (question->qtype != kDNSType_SRV)
                                {
                                LogMsg("AutoTunnelCallback: Bad question type %d in TC_STATE_SRV_PEER", question->qtype);
                                }
                        LogInfo("AutoTunnelCallback: SRV target name %##s", answer->rdata->u.srv.target.c);
                        tun->tc_state = TC_STATE_ADDR_PEER;
                        AssignDomainName(&tun->q.qname, &answer->rdata->u.srv.target);
                        tun->rmt_outer_port = answer->rdata->u.srv.port;
                        question->qtype = kDNSType_A;
                        mDNS_StartQuery(m, &tun->q);
                        return;
                case TC_STATE_ADDR_PEER:
                        if (question->qtype != kDNSType_A)
                                {
                                LogMsg("AutoTunnelCallback: Bad question type %d in TC_STATE_ADDR_PEER", question->qtype);
                                }
                        TunnelClientFinish(m, question, answer);
                        return;
                default:
                        LogMsg("AutoTunnelCallback: Unknown question %p", question);
                }
        }

// Must be called with the lock held
mDNSexport void AddNewClientTunnel(mDNS *const m, DNSQuestion *const q)
        {
        ClientTunnel *p = mallocL("ClientTunnel", sizeof(ClientTunnel));
        if (!p) return;
        AssignDomainName(&p->dstname, &q->qname);
        p->MarkedForDeletion = mDNSfalse;
        p->loc_inner      = zerov6Addr;
        p->loc_outer      = zerov4Addr;
        p->loc_outer6     = zerov6Addr;
        p->rmt_inner      = zerov6Addr;
        p->rmt_outer      = zerov4Addr;
        p->rmt_outer6     = zerov6Addr;
        p->rmt_outer_port = zeroIPPort;
        p->tc_state = TC_STATE_AAAA_PEER;
        p->next = m->TunnelClients;
        m->TunnelClients = p;           // We intentionally build list in reverse order

        p->q.InterfaceID      = mDNSInterface_Any;
        p->q.Target           = zeroAddr;
        AssignDomainName(&p->q.qname, &q->qname);
        p->q.qtype            = kDNSType_AAAA;
        p->q.qclass           = kDNSClass_IN;
        p->q.LongLived        = mDNSfalse;
        p->q.ExpectUnique     = mDNStrue;
        p->q.ForceMCast       = mDNSfalse;
        p->q.ReturnIntermed   = mDNStrue;
        p->q.SuppressUnusable = mDNSfalse;
        p->q.QuestionCallback = AutoTunnelCallback;
        p->q.QuestionContext  = p;

        LogInfo("AddNewClientTunnel start tun %p %##s (%s)%s", p, &q->qname.c, DNSTypeName(q->qtype), q->LongLived ? " LongLived" : "");
        mDNS_StartQuery_internal(m, &p->q);
        }

#endif // APPLE_OSX_mDNSResponder

#if COMPILER_LIKES_PRAGMA_MARK
#pragma mark -
#pragma mark - Power State & Configuration Change Management
#endif

mDNSlocal mStatus UpdateInterfaceList(mDNS *const m, mDNSs32 utc)
        {
        mDNSBool foundav4           = mDNSfalse;
        mDNSBool foundav6           = mDNSfalse;
        struct ifaddrs *ifa         = myGetIfAddrs(1);
        struct ifaddrs *v4Loopback  = NULL;
        struct ifaddrs *v6Loopback  = NULL;
        char defaultname[64];
#ifndef NO_IPV6
        int InfoSocket              = socket(AF_INET6, SOCK_DGRAM, 0);
        if (InfoSocket < 3 && errno != EAFNOSUPPORT) LogMsg("UpdateInterfaceList: InfoSocket error %d errno %d (%s)", InfoSocket, errno, strerror(errno));
#endif
        if (m->SleepState == SleepState_Sleeping) ifa = NULL;

        while (ifa)
                {
#if LIST_ALL_INTERFACES
                if (ifa->ifa_addr->sa_family == AF_APPLETALK)
                        LogMsg("UpdateInterfaceList: %5s(%d) Flags %04X Family %2d is AF_APPLETALK",
                                ifa->ifa_name, if_nametoindex(ifa->ifa_name), ifa->ifa_flags, ifa->ifa_addr->sa_family);
                else if (ifa->ifa_addr->sa_family == AF_LINK)
                        LogMsg("UpdateInterfaceList: %5s(%d) Flags %04X Family %2d is AF_LINK",
                                ifa->ifa_name, if_nametoindex(ifa->ifa_name), ifa->ifa_flags, ifa->ifa_addr->sa_family);
                else if (ifa->ifa_addr->sa_family != AF_INET && ifa->ifa_addr->sa_family != AF_INET6)
                        LogMsg("UpdateInterfaceList: %5s(%d) Flags %04X Family %2d not AF_INET (2) or AF_INET6 (30)",
                                ifa->ifa_name, if_nametoindex(ifa->ifa_name), ifa->ifa_flags, ifa->ifa_addr->sa_family);
                if (!(ifa->ifa_flags & IFF_UP))
                        LogMsg("UpdateInterfaceList: %5s(%d) Flags %04X Family %2d Interface not IFF_UP",
                                ifa->ifa_name, if_nametoindex(ifa->ifa_name), ifa->ifa_flags, ifa->ifa_addr->sa_family);
                if (!(ifa->ifa_flags & IFF_MULTICAST))
                        LogMsg("UpdateInterfaceList: %5s(%d) Flags %04X Family %2d Interface not IFF_MULTICAST",
                                ifa->ifa_name, if_nametoindex(ifa->ifa_name), ifa->ifa_flags, ifa->ifa_addr->sa_family);
                if (ifa->ifa_flags & IFF_POINTOPOINT)
                        LogMsg("UpdateInterfaceList: %5s(%d) Flags %04X Family %2d Interface IFF_POINTOPOINT",
                                ifa->ifa_name, if_nametoindex(ifa->ifa_name), ifa->ifa_flags, ifa->ifa_addr->sa_family);
                if (ifa->ifa_flags & IFF_LOOPBACK)
                        LogMsg("UpdateInterfaceList: %5s(%d) Flags %04X Family %2d Interface IFF_LOOPBACK",
                                ifa->ifa_name, if_nametoindex(ifa->ifa_name), ifa->ifa_flags, ifa->ifa_addr->sa_family);
#endif

                if (ifa->ifa_addr->sa_family == AF_LINK)
                        {
                        struct sockaddr_dl *sdl = (struct sockaddr_dl *)ifa->ifa_addr;
                        if (sdl->sdl_type == IFT_ETHER && sdl->sdl_alen == sizeof(m->PrimaryMAC) && mDNSSameEthAddress(&m->PrimaryMAC, &zeroEthAddr))
                                mDNSPlatformMemCopy(m->PrimaryMAC.b, sdl->sdl_data + sdl->sdl_nlen, 6);
                        }

                if (ifa->ifa_flags & IFF_UP && ifa->ifa_addr)
                        if (ifa->ifa_addr->sa_family == AF_INET || ifa->ifa_addr->sa_family == AF_INET6)
                                {
                                if (!ifa->ifa_netmask)
                                        {
                                        mDNSAddr ip;
                                        SetupAddr(&ip, ifa->ifa_addr);
                                        LogMsg("getifaddrs: ifa_netmask is NULL for %5s(%d) Flags %04X Family %2d %#a",
                                                ifa->ifa_name, if_nametoindex(ifa->ifa_name), ifa->ifa_flags, ifa->ifa_addr->sa_family, &ip);
                                        }
                                // Apparently it's normal for the sa_family of an ifa_netmask to sometimes be zero, so we don't complain about that
                                // <rdar://problem/5492035> getifaddrs is returning invalid netmask family for fw0 and vmnet
                                else if (ifa->ifa_netmask->sa_family != ifa->ifa_addr->sa_family && ifa->ifa_netmask->sa_family != 0)
                                        {
                                        mDNSAddr ip;
                                        SetupAddr(&ip, ifa->ifa_addr);
                                        LogMsg("getifaddrs ifa_netmask for %5s(%d) Flags %04X Family %2d %#a has different family: %d",
                                                ifa->ifa_name, if_nametoindex(ifa->ifa_name), ifa->ifa_flags, ifa->ifa_addr->sa_family, &ip, ifa->ifa_netmask->sa_family);
                                        }
                                        // Currently we use a few internal ones like mDNSInterfaceID_LocalOnly etc. that are negative values (0, -1, -2).
                                else if ((int)if_nametoindex(ifa->ifa_name) <= 0)
                                        {
                                        LogMsg("UpdateInterfaceList: if_nametoindex returned zero/negative value for %5s(%d)", ifa->ifa_name, if_nametoindex(ifa->ifa_name));
                                        }
                                else
                                        {
                                        // Make sure ifa_netmask->sa_family is set correctly
                                        // <rdar://problem/5492035> getifaddrs is returning invalid netmask family for fw0 and vmnet
                                        ifa->ifa_netmask->sa_family = ifa->ifa_addr->sa_family;
                                        int ifru_flags6 = 0;
#ifndef NO_IPV6
                                        struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)ifa->ifa_addr;
                                        if (ifa->ifa_addr->sa_family == AF_INET6 && InfoSocket >= 0)
                                                {
                                                struct in6_ifreq ifr6;
                                                mDNSPlatformMemZero((char *)&ifr6, sizeof(ifr6));
                                                strlcpy(ifr6.ifr_name, ifa->ifa_name, sizeof(ifr6.ifr_name));
                                                ifr6.ifr_addr = *sin6;
                                                if (ioctl(InfoSocket, SIOCGIFAFLAG_IN6, &ifr6) != -1)
                                                        ifru_flags6 = ifr6.ifr_ifru.ifru_flags6;
                                                verbosedebugf("%s %.16a %04X %04X", ifa->ifa_name, &sin6->sin6_addr, ifa->ifa_flags, ifru_flags6);
                                                }
#endif
                                        if (!(ifru_flags6 & (IN6_IFF_NOTREADY | IN6_IFF_DETACHED | IN6_IFF_DEPRECATED | IN6_IFF_TEMPORARY)))
                                                {
                                                if (ifa->ifa_flags & IFF_LOOPBACK)
                                                        {
                                                        if (ifa->ifa_addr->sa_family == AF_INET)     v4Loopback = ifa;
#ifndef NO_IPV6
                                                        else if (sin6->sin6_addr.s6_addr[0] != 0xFD) v6Loopback = ifa;
#endif
                                                        }
                                                else
                                                        {
                                                        NetworkInterfaceInfoOSX *i = AddInterfaceToList(m, ifa, utc);
                                                        if (i && MulticastInterface(i) && i->ifinfo.Advertise)
                                                                {
                                                                if (ifa->ifa_addr->sa_family == AF_INET) foundav4 = mDNStrue;
                                                                else                                     foundav6 = mDNStrue;
                                                                }
                                                        }
                                                }
                                        }
                                }
                ifa = ifa->ifa_next;
                }

        // For efficiency, we don't register a loopback interface when other interfaces of that family are available and advertising
        if (!foundav4 && v4Loopback) AddInterfaceToList(m, v4Loopback, utc);
        if (!foundav6 && v6Loopback) AddInterfaceToList(m, v6Loopback, utc);

        // Now the list is complete, set the McastTxRx setting for each interface.
        NetworkInterfaceInfoOSX *i;
        for (i = m->p->InterfaceList; i; i = i->next)
                if (i->Exists)
                        {
                        mDNSBool txrx = MulticastInterface(i);
#if USE_V6_ONLY_WHEN_NO_ROUTABLE_V4
                        txrx = txrx && ((i->ifinfo.ip.type == mDNSAddrType_IPv4) || !FindRoutableIPv4(m, i->scope_id));
#endif
                        if (i->ifinfo.McastTxRx != txrx)
                                {
                                i->ifinfo.McastTxRx = txrx;
                                i->Exists = 2; // State change; need to deregister and reregister this interface
                                }
                        }

#ifndef NO_IPV6
        if (InfoSocket >= 0) close(InfoSocket);
#endif

        // If we haven't set up AutoTunnelHostAddr yet, do it now
        if (!mDNSSameEthAddress(&m->PrimaryMAC, &zeroEthAddr) && m->AutoTunnelHostAddr.b[0] == 0)
                {
                m->AutoTunnelHostAddr.b[0x0] = 0xFD;            // Required prefix for "locally assigned" ULA (See RFC 4193)
                m->AutoTunnelHostAddr.b[0x1] = mDNSRandom(255);
                m->AutoTunnelHostAddr.b[0x2] = mDNSRandom(255);
                m->AutoTunnelHostAddr.b[0x3] = mDNSRandom(255);
                m->AutoTunnelHostAddr.b[0x4] = mDNSRandom(255);
                m->AutoTunnelHostAddr.b[0x5] = mDNSRandom(255);
                m->AutoTunnelHostAddr.b[0x6] = mDNSRandom(255);
                m->AutoTunnelHostAddr.b[0x7] = mDNSRandom(255);
                m->AutoTunnelHostAddr.b[0x8] = m->PrimaryMAC.b[0] ^ 0x02;       // See RFC 3513, Appendix A for explanation
                m->AutoTunnelHostAddr.b[0x9] = m->PrimaryMAC.b[1];
                m->AutoTunnelHostAddr.b[0xA] = m->PrimaryMAC.b[2];
                m->AutoTunnelHostAddr.b[0xB] = 0xFF;
                m->AutoTunnelHostAddr.b[0xC] = 0xFE;
                m->AutoTunnelHostAddr.b[0xD] = m->PrimaryMAC.b[3];
                m->AutoTunnelHostAddr.b[0xE] = m->PrimaryMAC.b[4];
                m->AutoTunnelHostAddr.b[0xF] = m->PrimaryMAC.b[5];
                m->AutoTunnelLabel.c[0] = mDNS_snprintf((char*)m->AutoTunnelLabel.c+1, 254, "AutoTunnel-%02X-%02X-%02X-%02X-%02X-%02X-%02X-%02X",
                        m->AutoTunnelHostAddr.b[0x8], m->AutoTunnelHostAddr.b[0x9], m->AutoTunnelHostAddr.b[0xA], m->AutoTunnelHostAddr.b[0xB],
                        m->AutoTunnelHostAddr.b[0xC], m->AutoTunnelHostAddr.b[0xD], m->AutoTunnelHostAddr.b[0xE], m->AutoTunnelHostAddr.b[0xF]);
                LogInfo("m->AutoTunnelLabel %#s", m->AutoTunnelLabel.c);
                }
        
        mDNS_snprintf(defaultname, sizeof(defaultname), "%.*s-%02X%02X%02X%02X%02X%02X", HINFO_HWstring_prefixlen, HINFO_HWstring,
                m->PrimaryMAC.b[0], m->PrimaryMAC.b[1], m->PrimaryMAC.b[2], m->PrimaryMAC.b[3], m->PrimaryMAC.b[4], m->PrimaryMAC.b[5]);

        // Set up the nice label
        domainlabel nicelabel;
        nicelabel.c[0] = 0;
        GetUserSpecifiedFriendlyComputerName(&nicelabel);
        if (nicelabel.c[0] == 0)
                {
                debugf("Couldn’t read user-specified Computer Name; using default “%s” instead", defaultname);
                MakeDomainLabelFromLiteralString(&nicelabel, defaultname);
                }

        // Set up the RFC 1034-compliant label
        domainlabel hostlabel;
        hostlabel.c[0] = 0;
        GetUserSpecifiedLocalHostName(&hostlabel);
        if (hostlabel.c[0] == 0)
                {
                debugf("Couldn’t read user-specified Local Hostname; using default “%s.local” instead", defaultname);
                MakeDomainLabelFromLiteralString(&hostlabel, defaultname);
                }

        mDNSBool namechange = mDNSfalse;

        // We use a case-sensitive comparison here because even though changing the capitalization
        // of the name alone is not significant to DNS, it's still a change from the user's point of view
        if (SameDomainLabelCS(m->p->usernicelabel.c, nicelabel.c))
                debugf("Usernicelabel (%#s) unchanged since last time; not changing m->nicelabel (%#s)", m->p->usernicelabel.c, m->nicelabel.c);
        else
                {
                if (m->p->usernicelabel.c[0])   // Don't show message first time through, when we first read name from prefs on boot
                        LogMsg("User updated Computer Name from “%#s” to “%#s”", m->p->usernicelabel.c, nicelabel.c);
                m->p->usernicelabel = m->nicelabel = nicelabel;
                namechange = mDNStrue;
                }

        if (SameDomainLabelCS(m->p->userhostlabel.c, hostlabel.c))
                debugf("Userhostlabel (%#s) unchanged since last time; not changing m->hostlabel (%#s)", m->p->userhostlabel.c, m->hostlabel.c);
        else
                {
                if (m->p->userhostlabel.c[0])   // Don't show message first time through, when we first read name from prefs on boot
                        LogMsg("User updated Local Hostname from “%#s” to “%#s”", m->p->userhostlabel.c, hostlabel.c);
                m->p->userhostlabel = m->hostlabel = hostlabel;
                mDNS_SetFQDN(m);
                namechange = mDNStrue;
                }

#if APPLE_OSX_mDNSResponder
        if (namechange)         // If either name has changed, we need to tickle our AutoTunnel state machine to update its registered records
                {
                DomainAuthInfo *info;
                for (info = m->AuthInfoList; info; info = info->next)
                                if (info->AutoTunnel) AutoTunnelHostNameChanged(m, info);
                }
#endif // APPLE_OSX_mDNSResponder

        return(mStatus_NoError);
        }

// Returns number of leading one-bits in mask: 0-32 for IPv4, 0-128 for IPv6
// Returns -1 if all the one-bits are not contiguous
mDNSlocal int CountMaskBits(mDNSAddr *mask)
        {
        int i = 0, bits = 0;
        int bytes = mask->type == mDNSAddrType_IPv4 ? 4 : mask->type == mDNSAddrType_IPv6 ? 16 : 0;
        while (i < bytes)
                {
                mDNSu8 b = mask->ip.v6.b[i++];
                while (b & 0x80) { bits++; b <<= 1; }
                if (b) return(-1);
                }
        while (i < bytes) if (mask->ip.v6.b[i++]) return(-1);
        return(bits);
        }

// returns count of non-link local V4 addresses registered
mDNSlocal int SetupActiveInterfaces(mDNS *const m, mDNSs32 utc)
        {
        NetworkInterfaceInfoOSX *i;
        int count = 0;
        for (i = m->p->InterfaceList; i; i = i->next)
                if (i->Exists)
                        {
                        NetworkInterfaceInfo *const n = &i->ifinfo;
                        NetworkInterfaceInfoOSX *primary = SearchForInterfaceByName(m, i->ifinfo.ifname, AAAA_OVER_V4 ? AF_UNSPEC : i->sa_family);
                        if (!primary) LogMsg("SetupActiveInterfaces ERROR! SearchForInterfaceByName didn't find %s", i->ifinfo.ifname);

                        if (i->Registered && i->Registered != primary)  // Sanity check
                                {
                                LogMsg("SetupActiveInterfaces ERROR! n->Registered %p != primary %p", i->Registered, primary);
                                i->Registered = mDNSNULL;
                                }

                        if (!i->Registered)
                                {
                                // Note: If i->Registered is set, that means we've called mDNS_RegisterInterface() for this interface,
                                // so we need to make sure we call mDNS_DeregisterInterface() before disposing it.
                                // If i->Registered is NOT set, then we haven't registered it and we should not try to deregister it
                                //

                                i->Registered = primary;

                                // If i->LastSeen == utc, then this is a brand-new interface, just created, or an interface that never went away.
                                // If i->LastSeen != utc, then this is an old interface, previously seen, that went away for (utc - i->LastSeen) seconds.
                                // If the interface is an old one that went away and came back in less than a minute, then we're in a flapping scenario.
                                i->Occulting = !(i->ifa_flags & IFF_LOOPBACK) && (utc - i->LastSeen > 0 && utc - i->LastSeen < 60);

                                mDNS_RegisterInterface(m, n, i->Flashing && i->Occulting);

                                if (!mDNSAddressIsLinkLocal(&n->ip)) count++;
                                LogInfo("SetupActiveInterfaces:   Registered    %5s(%lu) %.6a InterfaceID %p(%p), primary %p, %#a/%d%s%s%s",
                                        i->ifinfo.ifname, i->scope_id, &i->BSSID, i->ifinfo.InterfaceID, i, primary, &n->ip, CountMaskBits(&n->mask),
                                        i->Flashing        ? " (Flashing)"  : "",
                                        i->Occulting       ? " (Occulting)" : "",
                                        n->InterfaceActive ? " (Primary)"   : "");

                                if (!n->McastTxRx)
                                        debugf("SetupActiveInterfaces:   No Tx/Rx on   %5s(%lu) %.6a InterfaceID %p %#a", i->ifinfo.ifname, i->scope_id, &i->BSSID, i->ifinfo.InterfaceID, &n->ip);
                                else
                                        {
                                        if (i->sa_family == AF_INET)
                                                {
                                                struct ip_mreq imr;
                                                primary->ifa_v4addr.s_addr = n->ip.ip.v4.NotAnInteger;
                                                imr.imr_multiaddr.s_addr = AllDNSLinkGroup_v4.ip.v4.NotAnInteger;
                                                imr.imr_interface        = primary->ifa_v4addr;
        
                                                // If this is our *first* IPv4 instance for this interface name, we need to do a IP_DROP_MEMBERSHIP first,
                                                // before trying to join the group, to clear out stale kernel state which may be lingering.
                                                // In particular, this happens with removable network interfaces like USB Ethernet adapters -- the kernel has stale state
                                                // from the last time the USB Ethernet adapter was connected, and part of the kernel thinks we've already joined the group
                                                // on that interface (so we get EADDRINUSE when we try to join again) but a different part of the kernel thinks we haven't
                                                // joined the group (so we receive no multicasts). Doing an IP_DROP_MEMBERSHIP before joining seems to flush the stale state.
                                                // Also, trying to make the code leave the group when the adapter is removed doesn't work either,
                                                // because by the time we get the configuration change notification, the interface is already gone,
                                                // so attempts to unsubscribe fail with EADDRNOTAVAIL (errno 49 "Can't assign requested address").
                                                // <rdar://problem/5585972> IP_ADD_MEMBERSHIP fails for previously-connected removable interfaces
                                                if (SearchForInterfaceByName(m, i->ifinfo.ifname, AF_INET) == i)
                                                        {
                                                        LogInfo("SetupActiveInterfaces: %5s(%lu) Doing precautionary IP_DROP_MEMBERSHIP for %.4a on %.4a", i->ifinfo.ifname, i->scope_id, &imr.imr_multiaddr, &imr.imr_interface);
                                                        mStatus err = setsockopt(m->p->permanentsockets.sktv4, IPPROTO_IP, IP_DROP_MEMBERSHIP, &imr, sizeof(imr));
                                                        if (err < 0 && (errno != EADDRNOTAVAIL))
                                                                LogMsg("setsockopt - IP_DROP_MEMBERSHIP error %d errno %d (%s)", err, errno, strerror(errno));
                                                        }
        
                                                LogInfo("SetupActiveInterfaces: %5s(%lu) joining IPv4 mcast group %.4a on %.4a", i->ifinfo.ifname, i->scope_id, &imr.imr_multiaddr, &imr.imr_interface);
                                                mStatus err = setsockopt(m->p->permanentsockets.sktv4, IPPROTO_IP, IP_ADD_MEMBERSHIP, &imr, sizeof(imr));
                                                // Joining same group twice can give "Address already in use" error -- no need to report that
                                                if (err < 0 && (errno != EADDRINUSE))
                                                        LogMsg("setsockopt - IP_ADD_MEMBERSHIP error %d errno %d (%s) group %.4a on %.4a", err, errno, strerror(errno), &imr.imr_multiaddr, &imr.imr_interface);
                                                }
#ifndef NO_IPV6
                                        if (i->sa_family == AF_INET6)
                                                {
                                                struct ipv6_mreq i6mr;
                                                i6mr.ipv6mr_interface = primary->scope_id;
                                                i6mr.ipv6mr_multiaddr = *(struct in6_addr*)&AllDNSLinkGroup_v6.ip.v6;
        
                                                if (SearchForInterfaceByName(m, i->ifinfo.ifname, AF_INET6) == i)
                                                        {
                                                        LogInfo("SetupActiveInterfaces: %5s(%lu) Doing precautionary IPV6_LEAVE_GROUP for %.16a on %u", i->ifinfo.ifname, i->scope_id, &i6mr.ipv6mr_multiaddr, i6mr.ipv6mr_interface);
                                                        mStatus err = setsockopt(m->p->permanentsockets.sktv6, IPPROTO_IPV6, IPV6_LEAVE_GROUP, &i6mr, sizeof(i6mr));
                                                        if (err < 0 && (errno != EADDRNOTAVAIL))
                                                                LogMsg("setsockopt - IPV6_LEAVE_GROUP error %d errno %d (%s) group %.16a on %u", err, errno, strerror(errno), &i6mr.ipv6mr_multiaddr, i6mr.ipv6mr_interface);
                                                        }
        
                                                LogInfo("SetupActiveInterfaces: %5s(%lu) joining IPv6 mcast group %.16a on %u", i->ifinfo.ifname, i->scope_id, &i6mr.ipv6mr_multiaddr, i6mr.ipv6mr_interface);
                                                mStatus err = setsockopt(m->p->permanentsockets.sktv6, IPPROTO_IPV6, IPV6_JOIN_GROUP, &i6mr, sizeof(i6mr));
                                                // Joining same group twice can give "Address already in use" error -- no need to report that
                                                if (err < 0 && (errno != EADDRINUSE))
                                                        LogMsg("setsockopt - IPV6_JOIN_GROUP error %d errno %d (%s) group %.16a on %u", err, errno, strerror(errno), &i6mr.ipv6mr_multiaddr, i6mr.ipv6mr_interface);
                                                }
#endif
                                        }
                                }
                        }

        return count;
        }

mDNSlocal void MarkAllInterfacesInactive(mDNS *const m, mDNSs32 utc)
        {
        NetworkInterfaceInfoOSX *i;
        for (i = m->p->InterfaceList; i; i = i->next)
                {
                if (i->Exists) i->LastSeen = utc;
                i->Exists = mDNSfalse;
                }
        }

// returns count of non-link local V4 addresses deregistered
mDNSlocal int ClearInactiveInterfaces(mDNS *const m, mDNSs32 utc)
        {
        // First pass:
        // If an interface is going away, then deregister this from the mDNSCore.
        // We also have to deregister it if the primary interface that it's using for its InterfaceID is going away.
        // We have to do this because mDNSCore will use that InterfaceID when sending packets, and if the memory
        // it refers to has gone away we'll crash.
        NetworkInterfaceInfoOSX *i;
        int count = 0;
        for (i = m->p->InterfaceList; i; i = i->next)
                {
                // If this interface is no longer active, or its InterfaceID is changing, deregister it
                NetworkInterfaceInfoOSX *primary = SearchForInterfaceByName(m, i->ifinfo.ifname, AAAA_OVER_V4 ? AF_UNSPEC : i->sa_family);
                if (i->Registered)
                        if (i->Exists == 0 || i->Exists == 2 || i->Registered != primary)
                                {
                                i->Flashing = !(i->ifa_flags & IFF_LOOPBACK) && (utc - i->AppearanceTime < 60);
                                LogInfo("ClearInactiveInterfaces: Deregistering %5s(%lu) %.6a InterfaceID %p(%p), primary %p, %#a/%d%s%s%s",
                                        i->ifinfo.ifname, i->scope_id, &i->BSSID, i->ifinfo.InterfaceID, i, primary,
                                        &i->ifinfo.ip, CountMaskBits(&i->ifinfo.mask),
                                        i->Flashing               ? " (Flashing)"  : "",
                                        i->Occulting              ? " (Occulting)" : "",
                                        i->ifinfo.InterfaceActive ? " (Primary)"   : "");
                                mDNS_DeregisterInterface(m, &i->ifinfo, i->Flashing && i->Occulting);
                                if (!mDNSAddressIsLinkLocal(&i->ifinfo.ip)) count++;
                                i->Registered = mDNSNULL;
                                // Note: If i->Registered is set, that means we've called mDNS_RegisterInterface() for this interface,
                                // so we need to make sure we call mDNS_DeregisterInterface() before disposing it.
                                // If i->Registered is NOT set, then it's not registered and we should not call mDNS_DeregisterInterface() on it.

                                // Caution: If we ever decide to add code here to leave the multicast group, we need to make sure that this
                                // is the LAST representative of this physical interface, or we'll unsubscribe from the group prematurely.
                                }
                }

        // Second pass:
        // Now that everything that's going to deregister has done so, we can clean up and free the memory
        NetworkInterfaceInfoOSX **p = &m->p->InterfaceList;
        while (*p)
                {
                i = *p;
                // If no longer active, delete interface from list and free memory
                if (!i->Exists)
                        {
                        if (i->LastSeen == utc) i->LastSeen = utc - 1;
                        mDNSBool delete = (NumCacheRecordsForInterfaceID(m, i->ifinfo.InterfaceID) == 0) && (utc - i->LastSeen >= 60);
                        LogInfo("ClearInactiveInterfaces: %-13s %5s(%lu) %.6a InterfaceID %p(%p) %#a/%d Age %d%s", delete ? "Deleting" : "Holding",
                                i->ifinfo.ifname, i->scope_id, &i->BSSID, i->ifinfo.InterfaceID, i,
                                &i->ifinfo.ip, CountMaskBits(&i->ifinfo.mask), utc - i->LastSeen,
                                i->ifinfo.InterfaceActive ? " (Primary)" : "");
#if APPLE_OSX_mDNSResponder
                        if (i->BPF_fd >= 0) CloseBPF(i);
#endif // APPLE_OSX_mDNSResponder
                        if (delete)
                                {
                                *p = i->next;
                                freeL("NetworkInterfaceInfoOSX", i);
                                continue;       // After deleting this object, don't want to do the "p = &i->next;" thing at the end of the loop
                                }
                        }
                p = &i->next;
                }
        return count;
        }

mDNSlocal void AppendDNameListElem(DNameListElem ***List, mDNSu32 uid, domainname *name)
        {
        DNameListElem *dnle = (DNameListElem*) mallocL("DNameListElem/AppendDNameListElem", sizeof(DNameListElem));
        if (!dnle) LogMsg("ERROR: AppendDNameListElem: memory exhausted");
        else
                {
                dnle->next = mDNSNULL;
                dnle->uid  = uid;
                AssignDomainName(&dnle->name, name);
                **List = dnle;
                *List = &dnle->next;
                }
        }

mDNSlocal int compare_dns_configs(const void *aa, const void *bb)
        {
        dns_resolver_t *a = *(dns_resolver_t**)aa;
        dns_resolver_t *b = *(dns_resolver_t**)bb;
        
        return (a->search_order < b->search_order) ? -1 : (a->search_order == b->search_order) ? 0 : 1;
        }

mDNSlocal void ConfigResolvers(mDNS *const m, dns_config_t *config, mDNSBool scope, mDNSBool setsearch, mDNSBool setservers)
        {
        int i;
        domainname d;
#if DNSINFO_VERSION >= 20091104
        dns_resolver_t **resolver = scope ? config->scoped_resolver : config->resolver;
        int nresolvers = scope ? config->n_scoped_resolver : config->n_resolver;
#else
        (void) scope; // unused
        dns_resolver_t **resolver = config->resolver;
        int nresolvers = config->n_resolver;
#endif

        // Currently we don't support search lists for scoped resolvers. The WAB support for this will be added later.
        if (setsearch && !scope && nresolvers)
                {
                // Due to the vagaries of Apple's SystemConfiguration and dnsinfo.h APIs, if there are no search domains
                // listed, then you're supposed to interpret the "domain" field as also being the search domain, but if
                // there *are* search domains listed, then you're supposed to ignore the "domain" field completely and
                // instead use the search domain list as the sole authority for what domains to search and in what order
                // (and the domain from the "domain" field will also appear somewhere in that list).
                // Also, all search domains get added to the search list for resolver[0], so the domains and/or
                // search lists for other resolvers in the list need to be ignored.
                //
                // Note: Starting DNSINFO_VERSION 20091104, search list is present only in the first resolver (resolver 0).
                // i.e., n_search for the first resolver is always non-zero. We don't guard it with #ifs for better readability

                if (resolver[0]->n_search == 0)
                        {
                        LogInfo("ConfigResolvers: (%s) configuring zeroth domain as search list %s", scope ? "Scoped" : "Non-scoped", resolver[0]->domain);
                        mDNS_AddSearchDomain_CString(resolver[0]->domain);
                        }
                else
                        {
                        for (i = 0; i < resolver[0]->n_search; i++)
                                {
                                LogInfo("ConfigResolvers: (%s) configuring search list %s", scope ? "Scoped" : "Non-scoped", resolver[0]->search[i]);
                                mDNS_AddSearchDomain_CString(resolver[0]->search[i]);
                                }
                        }
                }

        if (!setservers) return;

        // For the "default" resolver ("resolver #1") the "domain" value is bogus and we need to ignore it.
        // e.g. the default resolver's "domain" value might say "apple.com", which indicates that this resolver
        // is only for names that fall under "apple.com", but that's not correct. Actually the default resolver is
        // for all names not covered by a more specific resolver (i.e. its domain should be ".", the root domain).
        //
        // Note: Starting DNSINFO_VERSION 20091104, domain value of this first resolver (resolver 0) is always NULL.
        // We don't guard it with #ifs for better readability
        // 
        if ((nresolvers != 0) && resolver[0]->domain)
                resolver[0]->domain[0] = 0; // don't stop pointing at the memory, just change the first byte

        qsort(resolver, nresolvers, sizeof(dns_resolver_t*), compare_dns_configs);
                                
        for (i = 0; i < nresolvers; i++)
                {       
                int n;
                dns_resolver_t *r = resolver[i];
                mDNSInterfaceID interface = mDNSInterface_Any;
                int disabled = 0;
                                        
                LogInfo("ConfigResolvers: %s resolver[%d] domain %s n_nameserver %d", scope ? "Scoped" : "", i, r->domain, r->n_nameserver);

                // On Tiger, dnsinfo entries for mDNS domains have port 5353, the mDNS port.  Ignore them.
                // Note: Unlike the BSD Sockets APIs (where TCP and UDP port numbers are universally in network byte order)
                // in Apple's "dnsinfo.h" API the port number is declared to be a "uint16_t in host byte order"
                // We also don't need to do any more work if there are no nameserver addresses
                if (r->port == 5353 || r->n_nameserver == 0) continue;
                                        
                if (!r->domain || !*r->domain) d.c[0] = 0;
                else if (!MakeDomainNameFromDNSNameString(&d, r->domain))
                        { LogMsg("ConfigResolvers: config->resolver[%d] bad domain %s", i, r->domain); continue; }

                // DNS server option parsing
                if (r->options != NULL)
                        {
                        char *nextOption = r->options;
                        char *currentOption = NULL;
                        while ((currentOption = strsep(&nextOption, " ")) != NULL && currentOption[0] != 0)
                                {
                                // The option may be in the form of interface=xxx where xxx is an interface name.
                                if (strncmp(currentOption, kInterfaceSpecificOption, sizeof(kInterfaceSpecificOption) - 1) == 0)
                                        {
                                        NetworkInterfaceInfoOSX *ni;
                                        char    ifname[IF_NAMESIZE+1];
                                        mDNSu32 ifindex = 0;
                                        // If something goes wrong finding the interface, create the server entry anyhow but mark it as disabled.
                                        // This allows us to block these special queries from going out on the wire.
                                        strlcpy(ifname, currentOption + sizeof(kInterfaceSpecificOption)-1, sizeof(ifname));
                                        ifindex = if_nametoindex(ifname);
                                        if (ifindex == 0) { disabled = 1; LogMsg("ConfigResolvers: RegisterSplitDNS interface specific - interface %s not found", ifname); continue; }
                                        LogInfo("ConfigResolvers: interface specific entry: %s on %s (%d)", r->domain, ifname, ifindex);
                                        // Find the interface. Can't use mDNSPlatformInterfaceIDFromInterfaceIndex
                                        // because that will call mDNSMacOSXNetworkChanged if the interface doesn't exist
                                        for (ni = m->p->InterfaceList; ni; ni = ni->next)
                                                if (ni->ifinfo.InterfaceID && ni->scope_id == ifindex) break;
                                        if (ni != NULL) interface = ni->ifinfo.InterfaceID;
                                        if (interface == mDNSNULL)
                                                {
                                                disabled = 1;
                                                LogMsg("ConfigResolvers: RegisterSplitDNS interface specific - index %d (%s) not found", ifindex, ifname);
                                                continue;
                                                }
                                        }
                                }
                        }

                // flags and if_index are defined only from this DNSINFO_VERSION onwards. Currently these
                // fields are zero for non-scoped resolvers. For now, these fields have non-zero values only
                // for scoped_resolvers.
#if DNSINFO_VERSION >= 20091104
                if (scope && (r->flags & DNS_RESOLVER_FLAGS_SCOPED) && (r->if_index != 0))
                        {
                        NetworkInterfaceInfoOSX *ni;
                        interface = mDNSNULL;
                        for (ni = m->p->InterfaceList; ni; ni = ni->next)
                                if (ni->ifinfo.InterfaceID && ni->scope_id == r->if_index) break;
                        if (ni != NULL) interface = ni->ifinfo.InterfaceID;
                        if (interface == mDNSNULL)
                                {
                                disabled = 1;
                                LogMsg("ConfigResolvers: interface specific index %d not found", r->if_index);
                                continue;
                                }
                        }
#endif

                for (n = 0; n < r->n_nameserver; n++)
                        if (r->nameserver[n]->sa_family == AF_INET || r->nameserver[n]->sa_family == AF_INET6)
                                {
                                mDNSAddr saddr;
                                // mDNSAddr saddr = { mDNSAddrType_IPv4, { { { 192, 168, 1, 1 } } } }; // for testing
                                if (SetupAddr(&saddr, r->nameserver[n])) LogMsg("RegisterSplitDNS: bad IP address");
                                else
                                        {
                                        mDNSBool scopedDNS = mDNSfalse;
                                        DNSServer *s;
#if DNSINFO_VERSION >= 20091104
                                        // By setting scoped, this DNSServer can only be picked if the right interfaceID
                                        // is given in the question
                                        if (scope && (r->flags & DNS_RESOLVER_FLAGS_SCOPED) && (interface == mDNSNULL))
                                                LogMsg("ConfigResolvers: ERROR: scoped is set but if_index %d is invalid for DNSServer %#a:%d", r->if_index, &saddr, mDNSVal16(r->port ? mDNSOpaque16fromIntVal(r->port) : UnicastDNSPort));
                                        else
                                                scopedDNS = (scope && (r->flags & DNS_RESOLVER_FLAGS_SCOPED)) ? mDNStrue : mDNSfalse;
#endif
                                        s = mDNS_AddDNSServer(m, &d, interface, &saddr, r->port ? mDNSOpaque16fromIntVal(r->port) : UnicastDNSPort, scopedDNS);
                                        if (s)
                                                {
                                                if (disabled) s->teststate = DNSServer_Disabled;
                                                LogInfo("ConfigResolvers: DNS server %#a:%d for domain %##s from slot %d,%d", &s->addr, mDNSVal16(s->port), d.c, i, n);
                                                }
                                        }
                                }
                }
        }

mDNSexport void mDNSPlatformSetDNSConfig(mDNS *const m, mDNSBool setservers, mDNSBool setsearch, domainname *const fqdn, DNameListElem **RegDomains, DNameListElem **BrowseDomains)
        {
        int i;
        char buf[MAX_ESCAPED_DOMAIN_NAME];      // Max legal C-string name, including terminating NUL
        domainname d;

        // Need to set these here because we need to do this even if SCDynamicStoreCreate() or SCDynamicStoreCopyValue() below don't succeed
        if (fqdn)          fqdn->c[0]      = 0;
        if (RegDomains   ) *RegDomains     = NULL;
        if (BrowseDomains) *BrowseDomains  = NULL;

        LogInfo("mDNSPlatformSetDNSConfig:%s%s%s%s%s",
                setservers    ? " setservers"    : "",
                setsearch     ? " setsearch"     : "",
                fqdn          ? " fqdn"          : "",
                RegDomains    ? " RegDomains"    : "",
                BrowseDomains ? " BrowseDomains" : "");

        // Add the inferred address-based configuration discovery domains
        // (should really be in core code I think, not platform-specific)
        if (setsearch)
                {
                struct ifaddrs *ifa = mDNSNULL;
                struct sockaddr_in saddr;
                mDNSPlatformMemZero(&saddr, sizeof(saddr));
                saddr.sin_len = sizeof(saddr);
                saddr.sin_family = AF_INET;
                saddr.sin_port = 0;
                saddr.sin_addr.s_addr = *(in_addr_t *)&m->Router.ip.v4;

                // Don't add any reverse-IP search domains if doing the WAB bootstrap queries would cause dial-on-demand connection initiation
                if (!AddrRequiresPPPConnection((struct sockaddr *)&saddr)) ifa =  myGetIfAddrs(1);
                
                while (ifa)
                        {
                        mDNSAddr a, n;
                        if (ifa->ifa_addr->sa_family == AF_INET &&
                                ifa->ifa_netmask                    &&
                                !(ifa->ifa_flags & IFF_LOOPBACK)        &&
                                !SetupAddr(&a, ifa->ifa_addr)           &&
                                !mDNSv4AddressIsLinkLocal(&a.ip.v4)  )
                                {
                                // Apparently it's normal for the sa_family of an ifa_netmask to sometimes be incorrect, so we explicitly fix it here before calling SetupAddr
                                // <rdar://problem/5492035> getifaddrs is returning invalid netmask family for fw0 and vmnet
                                ifa->ifa_netmask->sa_family = ifa->ifa_addr->sa_family;         // Make sure ifa_netmask->sa_family is set correctly
                                SetupAddr(&n, ifa->ifa_netmask);
                                // 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(buf, sizeof(buf), "%d.%d.%d.%d.in-addr.arpa.", a.ip.v4.b[3] & n.ip.v4.b[3],
                                                                                                                                                         a.ip.v4.b[2] & n.ip.v4.b[2],
                                                                                                                                                         a.ip.v4.b[1] & n.ip.v4.b[1],
                                                                                                                                                         a.ip.v4.b[0] & n.ip.v4.b[0]);
                                mDNS_AddSearchDomain_CString(buf);
                                }
                        ifa = ifa->ifa_next;
                        }
                }

#ifndef MDNS_NO_DNSINFO
        if (setservers || setsearch)
                {
                dns_config_t *config = dns_configuration_copy();
                if (!config)
                        {
                        // When running on 10.3 (build 7xxx) and earlier, we don't expect dns_configuration_copy() to succeed
                        // On 10.4, calls to dns_configuration_copy() early in the boot process often fail.
                        // Apparently this is expected behaviour -- "not a bug".
                        // Accordingly, we suppress syslog messages for the first three minutes after boot.
                        // If we are still getting failures after three minutes, then we log them.
                        if (OSXVers > OSXVers_10_3_Panther && (mDNSu32)mDNSPlatformRawTime() > (mDNSu32)(mDNSPlatformOneSecond * 180))
                                LogMsg("mDNSPlatformSetDNSConfig: Error: dns_configuration_copy returned NULL");
                        }
                else
                        {
                        LogInfo("mDNSPlatformSetDNSConfig: config->n_resolver = %d", config->n_resolver);

#if APPLE_OSX_mDNSResponder
                                // Record the so-called "primary" domain, which we use as a hint to tell if the user is on a network set up
                                // by someone using Microsoft Active Directory using "local" as a private internal top-level domain
                                if (config->n_resolver && config->resolver[0]->domain && config->resolver[0]->n_nameserver && config->resolver[0]->nameserver[0])
                                        MakeDomainNameFromDNSNameString(&ActiveDirectoryPrimaryDomain, config->resolver[0]->domain);
                                else ActiveDirectoryPrimaryDomain.c[0] = 0;
                                //MakeDomainNameFromDNSNameString(&ActiveDirectoryPrimaryDomain, "test.local");
                                ActiveDirectoryPrimaryDomainLabelCount = CountLabels(&ActiveDirectoryPrimaryDomain);
                                if (config->n_resolver && config->resolver[0]->n_nameserver && SameDomainName(SkipLeadingLabels(&ActiveDirectoryPrimaryDomain, ActiveDirectoryPrimaryDomainLabelCount - 1), &localdomain))
                                        SetupAddr(&ActiveDirectoryPrimaryDomainServer, config->resolver[0]->nameserver[0]);
                                else
                                        {
                                        AssignDomainName(&ActiveDirectoryPrimaryDomain, (const domainname *)"");
                                        ActiveDirectoryPrimaryDomainLabelCount = 0;
                                        ActiveDirectoryPrimaryDomainServer = zeroAddr;
                                        }
#endif

                        ConfigResolvers(m, config, mDNSfalse, setsearch, setservers);
#if DNSINFO_VERSION >= 20091104
                        ConfigResolvers(m, config, mDNStrue, setsearch, setservers);
#endif
                        dns_configuration_free(config);
                        setservers = mDNSfalse;  // Done these now -- no need to fetch the same data from SCDynamicStore
                        setsearch  = mDNSfalse;
                        }
                }
#endif // MDNS_NO_DNSINFO

        SCDynamicStoreRef store = SCDynamicStoreCreate(NULL, CFSTR("mDNSResponder:mDNSPlatformSetDNSConfig"), NULL, NULL);
        if (!store)
                LogMsg("mDNSPlatformSetDNSConfig: SCDynamicStoreCreate failed: %s", SCErrorString(SCError()));
        else
                {
                CFDictionaryRef ddnsdict = SCDynamicStoreCopyValue(store, NetworkChangedKey_DynamicDNS);
                if (ddnsdict)
                        {
                        if (fqdn)
                                {
                                CFArrayRef fqdnArray = CFDictionaryGetValue(ddnsdict, CFSTR("HostNames"));
                                if (fqdnArray && CFArrayGetCount(fqdnArray) > 0)
                                        {
                                        // for now, we only look at the first array element.  if we ever support multiple configurations, we will walk the list
                                        CFDictionaryRef fqdnDict = CFArrayGetValueAtIndex(fqdnArray, 0);
                                        if (fqdnDict && DictionaryIsEnabled(fqdnDict))
                                                {
                                                CFStringRef name = CFDictionaryGetValue(fqdnDict, CFSTR("Domain"));
                                                if (name)
                                                        {
                                                        if (!CFStringGetCString(name, buf, sizeof(buf), kCFStringEncodingUTF8) ||
                                                                !MakeDomainNameFromDNSNameString(fqdn, buf) || !fqdn->c[0])
                                                                LogMsg("GetUserSpecifiedDDNSConfig SCDynamicStore bad DDNS host name: %s", buf[0] ? buf : "(unknown)");
                                                        else debugf("GetUserSpecifiedDDNSConfig SCDynamicStore DDNS host name: %s", buf);
                                                        }
                                                }
                                        }
                                }

                        if (RegDomains)
                                {
                                CFArrayRef regArray = CFDictionaryGetValue(ddnsdict, CFSTR("RegistrationDomains"));
                                if (regArray && CFArrayGetCount(regArray) > 0)
                                        {
                                        CFDictionaryRef regDict = CFArrayGetValueAtIndex(regArray, 0);
                                        if (regDict && DictionaryIsEnabled(regDict))
                                                {
                                                CFStringRef name = CFDictionaryGetValue(regDict, CFSTR("Domain"));
                                                if (name)
                                                        {
                                                        if (!CFStringGetCString(name, buf, sizeof(buf), kCFStringEncodingUTF8) ||
                                                                !MakeDomainNameFromDNSNameString(&d, buf) || !d.c[0])
                                                                LogMsg("GetUserSpecifiedDDNSConfig SCDynamicStore bad DDNS registration domain: %s", buf[0] ? buf : "(unknown)");
                                                        else
                                                                {
                                                                debugf("GetUserSpecifiedDDNSConfig SCDynamicStore DDNS registration domain: %s", buf);
                                                                AppendDNameListElem(&RegDomains, 0, &d);
                                                                }
                                                        }
                                                }
                                        }
                                }

                        if (BrowseDomains)
                                {
                                CFArrayRef browseArray = CFDictionaryGetValue(ddnsdict, CFSTR("BrowseDomains"));
                                if (browseArray)
                                        {
                                        for (i = 0; i < CFArrayGetCount(browseArray); i++)
                                                {
                                                CFDictionaryRef browseDict = CFArrayGetValueAtIndex(browseArray, i);
                                                if (browseDict && DictionaryIsEnabled(browseDict))
                                                        {
                                                        CFStringRef name = CFDictionaryGetValue(browseDict, CFSTR("Domain"));
                                                        if (name)
                                                                {
                                                                if (!CFStringGetCString(name, buf, sizeof(buf), kCFStringEncodingUTF8) ||
                                                                        !MakeDomainNameFromDNSNameString(&d, buf) || !d.c[0])
                                                                        LogMsg("GetUserSpecifiedDDNSConfig SCDynamicStore bad DDNS browsing domain: %s", buf[0] ? buf : "(unknown)");
                                                                else
                                                                        {
                                                                        debugf("GetUserSpecifiedDDNSConfig SCDynamicStore DDNS browsing domain: %s", buf);
                                                                        AppendDNameListElem(&BrowseDomains, 0, &d);
                                                                        }
                                                                }
                                                        }
                                                }
                                        }
                                }
                        CFRelease(ddnsdict);
                        }

                if (RegDomains)
                        {
                        CFDictionaryRef btmm = SCDynamicStoreCopyValue(store, NetworkChangedKey_BackToMyMac);
                        if (btmm)
                                {
                                CFIndex size = CFDictionaryGetCount(btmm);
                                const void *key[size];
                                const void *val[size];
                                CFDictionaryGetKeysAndValues(btmm, key, val);
                                for (i = 0; i < size; i++)
                                        {
                                        LogInfo("BackToMyMac %d", i);
                                        if (!CFStringGetCString(key[i], buf, sizeof(buf), kCFStringEncodingUTF8))
                                                LogMsg("Can't read BackToMyMac %d key %s", i, buf);
                                        else
                                                {
                                                mDNSu32 uid = atoi(buf);
                                                if (!CFStringGetCString(val[i], buf, sizeof(buf), kCFStringEncodingUTF8))
                                                        LogMsg("Can't read BackToMyMac %d val %s", i, buf);
                                                else if (MakeDomainNameFromDNSNameString(&d, buf) && d.c[0])
                                                        {
                                                        LogInfo("BackToMyMac %d %d %##s", i, uid, d.c);
                                                        AppendDNameListElem(&RegDomains, uid, &d);
                                                        }
                                                }
                                        }
                                CFRelease(btmm);
                                }
                        }

                if (setservers || setsearch)
                        {
                        CFDictionaryRef dict = SCDynamicStoreCopyValue(store, NetworkChangedKey_DNS);
                        if (dict)
                                {
                                if (setservers)
                                        {
                                        CFArrayRef values = CFDictionaryGetValue(dict, kSCPropNetDNSServerAddresses);
                                        if (values)
                                                {
                                                LogInfo("DNS Server Address values: %d", (int)CFArrayGetCount(values));
                                                for (i = 0; i < CFArrayGetCount(values); i++)
                                                        {
                                                        CFStringRef s = CFArrayGetValueAtIndex(values, i);
                                                        mDNSAddr addr = { mDNSAddrType_IPv4, { { { 0 } } } };
                                                        if (s && CFStringGetCString(s, buf, 256, kCFStringEncodingUTF8) &&
                                                                inet_aton(buf, (struct in_addr *) &addr.ip.v4))
                                                                {
                                                                LogInfo("Adding DNS server from dict: %s", buf);
                                                                mDNS_AddDNSServer(m, mDNSNULL, mDNSInterface_Any, &addr, UnicastDNSPort, mDNSfalse);
                                                                }
                                                        }
                                                }
                                        else LogInfo("No DNS Server Address values");
                                        }
                                if (setsearch)
                                        {
                                        // Add the manual and/or DHCP-dicovered search domains
                                        CFArrayRef searchDomains = CFDictionaryGetValue(dict, kSCPropNetDNSSearchDomains);
                                        if (searchDomains)
                                                {
                                                for (i = 0; i < CFArrayGetCount(searchDomains); i++)
                                                        {
                                                        CFStringRef s = CFArrayGetValueAtIndex(searchDomains, i);
                                                        if (s && CFStringGetCString(s, buf, sizeof(buf), kCFStringEncodingUTF8))
                                                                mDNS_AddSearchDomain_CString(buf);
                                                        }
                                                }
                                        else    // No kSCPropNetDNSSearchDomains, so use kSCPropNetDNSDomainName
                                                {
                                                // Due to the vagaries of Apple's SystemConfiguration and dnsinfo.h APIs, if there are no search domains
                                                // listed, then you're supposed to interpret the "domain" field as also being the search domain, but if
                                                // there *are* search domains listed, then you're supposed to ignore the "domain" field completely and
                                                // instead use the search domain list as the sole authority for what domains to search and in what order
                                                // (and the domain from the "domain" field will also appear somewhere in that list).
                                                CFStringRef string = CFDictionaryGetValue(dict, kSCPropNetDNSDomainName);
                                                if (string && CFStringGetCString(string, buf, sizeof(buf), kCFStringEncodingUTF8))
                                                        mDNS_AddSearchDomain_CString(buf);
                                                }
                                        }
                                CFRelease(dict);
                                }
                        }
                CFRelease(store);
                }
        }

mDNSexport mStatus mDNSPlatformGetPrimaryInterface(mDNS *const m, mDNSAddr *v4, mDNSAddr *v6, mDNSAddr *r)
        {
        char                            buf[256];
        (void)m; // Unused

        SCDynamicStoreRef store = SCDynamicStoreCreate(NULL, CFSTR("mDNSResponder:mDNSPlatformGetPrimaryInterface"), NULL, NULL);
        if (!store)
                LogMsg("mDNSPlatformGetPrimaryInterface: SCDynamicStoreCreate failed: %s", SCErrorString(SCError()));
        else
                {
                CFDictionaryRef dict = SCDynamicStoreCopyValue(store, NetworkChangedKey_IPv4);
                if (dict)
                        {
                        r->type  = mDNSAddrType_IPv4;
                        r->ip.v4 = zerov4Addr;
                        CFStringRef string = CFDictionaryGetValue(dict, kSCPropNetIPv4Router);
                        if (string)
                                {
                                if (!CFStringGetCString(string, buf, 256, kCFStringEncodingUTF8))
                                        LogMsg("Could not convert router to CString");
                                else
                                        {
                                        struct sockaddr_in saddr;
                                        saddr.sin_len = sizeof(saddr);
                                        saddr.sin_family = AF_INET;
                                        saddr.sin_port = 0;
                                        inet_aton(buf, &saddr.sin_addr);
                
                                        *(in_addr_t *)&r->ip.v4 = saddr.sin_addr.s_addr;
                                        }
                                }
                
                        string = CFDictionaryGetValue(dict, kSCDynamicStorePropNetPrimaryInterface);
                        if (string)
                                {
                                mDNSBool HavePrimaryGlobalv6 = mDNSfalse;  // does the primary interface have a global v6 address?
                                struct ifaddrs *ifa = myGetIfAddrs(1);
                
                                *v4 = *v6 = zeroAddr;
                
                                if (!CFStringGetCString(string, buf, 256, kCFStringEncodingUTF8)) { LogMsg("Could not convert router to CString"); goto exit; }
                
                                // find primary interface in list
                                while (ifa && (mDNSIPv4AddressIsZero(v4->ip.v4) || mDNSv4AddressIsLinkLocal(&v4->ip.v4) || !HavePrimaryGlobalv6))
                                        {
                                        mDNSAddr tmp6 = zeroAddr;
                                        if (!strcmp(buf, ifa->ifa_name))
                                                {
                                                if (ifa->ifa_addr->sa_family == AF_INET)
                                                        {
                                                        if (mDNSIPv4AddressIsZero(v4->ip.v4) || mDNSv4AddressIsLinkLocal(&v4->ip.v4)) SetupAddr(v4, ifa->ifa_addr);
                                                        }
                                                else if (ifa->ifa_addr->sa_family == AF_INET6)
                                                        {
                                                        SetupAddr(&tmp6, ifa->ifa_addr);
                                                        if (tmp6.ip.v6.b[0] >> 5 == 1)   // global prefix: 001
                                                                { HavePrimaryGlobalv6 = mDNStrue; *v6 = tmp6; }
                                                        }
                                                }
                                        else
                                                {
                                                // We'll take a V6 address from the non-primary interface if the primary interface doesn't have a global V6 address
                                                if (!HavePrimaryGlobalv6 && ifa->ifa_addr->sa_family == AF_INET6 && !v6->ip.v6.b[0])
                                                        {
                                                        SetupAddr(&tmp6, ifa->ifa_addr);
                                                        if (tmp6.ip.v6.b[0] >> 5 == 1) *v6 = tmp6;
                                                        }
                                                }
                                        ifa = ifa->ifa_next;
                                        }
                
                                // Note that while we advertise v6, we still require v4 (possibly NAT'd, but not link-local) because we must use
                                // V4 to communicate w/ our DNS server
                                }
                
                        exit:
                        CFRelease(dict);
                        }
                CFRelease(store);
                }
        return mStatus_NoError;
        }

mDNSexport void mDNSPlatformDynDNSHostNameStatusChanged(const domainname *const dname, const mStatus status)
        {
        LogInfo("mDNSPlatformDynDNSHostNameStatusChanged %d %##s", status, dname->c);
        char uname[MAX_ESCAPED_DOMAIN_NAME];    // Max legal C-string name, including terminating NUL
        ConvertDomainNameToCString(dname, uname);

        char *p = uname;
        while (*p)
                {
                *p = tolower(*p);
                if (!(*(p+1)) && *p == '.') *p = 0; // if last character, strip trailing dot
                p++;
                }

        // We need to make a CFDictionary called "State:/Network/DynamicDNS" containing (at present) a single entity.
        // That single entity is a CFDictionary with name "HostNames".
        // The "HostNames" CFDictionary contains a set of name/value pairs, where the each name is the FQDN
        // in question, and the corresponding value is a CFDictionary giving the state for that FQDN.
        // (At present we only support a single FQDN, so this dictionary holds just a single name/value pair.)
        // The CFDictionary for each FQDN holds (at present) a single name/value pair,
        // where the name is "Status" and the value is a CFNumber giving an errror code (with zero meaning success).

        const CFStringRef StateKeys [1] = { CFSTR("HostNames") };
        const CFStringRef HostKeys  [1] = { CFStringCreateWithCString(NULL, uname, kCFStringEncodingUTF8) };
        const CFStringRef StatusKeys[1] = { CFSTR("Status") };
        if (!HostKeys[0]) LogMsg("SetDDNSNameStatus: CFStringCreateWithCString(%s) failed", uname);
        else
                {
                const CFNumberRef StatusVals[1] = { CFNumberCreate(NULL, kCFNumberSInt32Type, &status) };
                if (!StatusVals[0]) LogMsg("SetDDNSNameStatus: CFNumberCreate(%d) failed", status);
                else
                        {
                        const CFDictionaryRef HostVals[1] = { CFDictionaryCreate(NULL, (void*)StatusKeys, (void*)StatusVals, 1, &kCFTypeDictionaryKeyCallBacks, &kCFTypeDictionaryValueCallBacks) };
                        if (HostVals[0])
                                {
                                const CFDictionaryRef StateVals[1] = { CFDictionaryCreate(NULL, (void*)HostKeys, (void*)HostVals, 1, &kCFTypeDictionaryKeyCallBacks, &kCFTypeDictionaryValueCallBacks) };
                                if (StateVals[0])
                                        {
                                        CFDictionaryRef StateDict = CFDictionaryCreate(NULL, (void*)StateKeys, (void*)StateVals, 1, &kCFTypeDictionaryKeyCallBacks, &kCFTypeDictionaryValueCallBacks);
                                        if (StateDict)
                                                {
                                                mDNSDynamicStoreSetConfig(kmDNSDynamicConfig, mDNSNULL, StateDict);
                                                CFRelease(StateDict);
                                                }
                                        CFRelease(StateVals[0]);
                                        }
                                CFRelease(HostVals[0]);
                                }
                        CFRelease(StatusVals[0]);
                        }
                CFRelease(HostKeys[0]);
                }
        }

#if APPLE_OSX_mDNSResponder
#if ! NO_AWACS

// checks whether a domain is present in Setup:/Network/BackToMyMac. Just because there is a key in the
// keychain for a domain, it does not become a valid BTMM domain. If things get inconsistent, this will
// help catch it
mDNSlocal mDNSBool IsBTMMDomain(domainname *d)
        {
        SCDynamicStoreRef store = SCDynamicStoreCreate(NULL, CFSTR("mDNSResponder:IsBTMMDomain"), NULL, NULL);
        if (!store)
                {
                LogMsg("IsBTMMDomain: SCDynamicStoreCreate failed: %s", SCErrorString(SCError()));
                return mDNSfalse;
                }
        CFDictionaryRef btmm = SCDynamicStoreCopyValue(store, NetworkChangedKey_BackToMyMac);
        if (btmm)
                {
                CFIndex size = CFDictionaryGetCount(btmm);
                char buf[MAX_ESCAPED_DOMAIN_NAME];      // Max legal C-string name, including terminating NUL
                const void *key[size];
                const void *val[size];
                domainname dom;
                int i;
                CFDictionaryGetKeysAndValues(btmm, key, val);
                for (i = 0; i < size; i++)
                        {
                        LogInfo("BackToMyMac %d", i);
                        if (!CFStringGetCString(key[i], buf, sizeof(buf), kCFStringEncodingUTF8))
                                LogMsg("IsBTMMDomain: ERROR!! Can't read BackToMyMac %d key %s", i, buf);
                        else
                                {
                                mDNSu32 uid = atoi(buf);
                                if (!CFStringGetCString(val[i], buf, sizeof(buf), kCFStringEncodingUTF8))
                                        LogMsg("IsBTMMDomain: Can't read BackToMyMac %d val %s", i, buf);
                                else if (MakeDomainNameFromDNSNameString(&dom, buf) && dom.c[0])
                                        {
                                        if (SameDomainName(&dom, d))
                                                {
                                                LogInfo("IsBTMMDomain: Domain %##s is a btmm domain, uid %u", d->c, uid);
                                                CFRelease(btmm);
                                                CFRelease(store);
                                                return mDNStrue;
                                                }
                                        }
                                }
                        }
                CFRelease(btmm);
                }
        CFRelease(store);
        LogInfo("IsBTMMDomain: Domain %##s not a btmm domain", d->c);
        return mDNSfalse;
        }

// Appends data to the buffer
mDNSlocal int AddOneItem(char *buf, int bufsz, char *data, int *currlen)
        {
        int len;

        len = strlcpy(buf + *currlen, data, bufsz - *currlen);
        if (len >= (bufsz - *currlen))
                {
                // if we have exceeded the space in buf, it has already been NULL terminated
                // and we have nothing more to do. Set currlen to the last byte so that the caller
                // knows to do the right thing
                LogMsg("AddOneItem: Exceeded the max buffer size currlen %d, len %d", *currlen, len);
                *currlen = bufsz - 1;
                return -1;
                }
        else { (*currlen) += len; }

        buf[*currlen] = ',';
        if (*currlen >= bufsz)
                {
                LogMsg("AddOneItem: ERROR!! How can currlen be %d", *currlen);
                *currlen = bufsz - 1;
                buf[*currlen] = 0;
                return -1;
                }
        // if we have filled up the buffer exactly, then there is no more work to do
        if (*currlen == bufsz - 1) { buf[*currlen] = 0; return -1; }
        (*currlen)++;
        return *currlen;
        }

// If we have at least one BTMM domain, then trigger the connection to the relay. If we have no
// BTMM domains, then bring down the connection to the relay.
mDNSlocal void UpdateBTMMRelayConnection(mDNS *const m)
        {
        DomainAuthInfo *BTMMDomain = mDNSNULL;
        DomainAuthInfo *FoundInList;
        static mDNSBool AWACSDConnected = mDNSfalse;
        char AllUsers[1024];    // maximum size of mach message
        char AllPass[1024];     // maximum size of mach message
        char username[MAX_DOMAIN_LABEL + 1];
        int currulen = 0;
        int currplen = 0;

        // if a domain is being deleted, we want to send a disconnect. If we send a disconnect now,
        // we may not be able to send the dns queries over the relay connection which may be needed
        // for sending the deregistrations. Hence, we need to delay sending the disconnect. But we
        // need to make sure that we send the disconnect before attempting the next connect as the
        // awacs connections are redirected based on usernames.
        //
        // For now we send a disconnect immediately. When we start sending dns queries over the relay
        // connection, we will need to fix this.

        for (FoundInList = m->AuthInfoList; FoundInList; FoundInList = FoundInList->next)
                if (!FoundInList->deltime && FoundInList->AutoTunnel && IsBTMMDomain(&FoundInList->domain))
                        {
                        // We need the passwd from the first domain.
                        BTMMDomain = FoundInList;
                        ConvertDomainLabelToCString_unescaped((domainlabel *)BTMMDomain->domain.c, username);
                        LogInfo("UpdateBTMMRelayConnection: user %s for domain %##s", username, BTMMDomain->domain.c);
                        if (AddOneItem(AllUsers, sizeof(AllUsers), username, &currulen) == -1) break;
                        if (AddOneItem(AllPass, sizeof(AllPass), BTMMDomain->b64keydata, &currplen) == -1) break;
                        }

        if (BTMMDomain) 
                {
                // In the normal case (where we neither exceed the buffer size nor write bytes that
                // fit exactly into the buffer), currulen/currplen should be a different size than
                // (AllUsers - 1) / (AllPass - 1). In that case, we need to override the "," with a NULL byte.

                if (currulen != (int)(sizeof(AllUsers) - 1)) AllUsers[currulen - 1] = 0;
                if (currplen != (int)(sizeof(AllPass) - 1)) AllPass[currplen - 1] = 0;

                LogInfo("UpdateBTMMRelayConnection: AWS_Connect for user %s", AllUsers);
                AWACS_Connect(AllUsers, AllPass, "hello.connectivity.me.com");
                AWACSDConnected = mDNStrue;
                }
        else
                {
                // Disconnect only if we connected previously
                if (AWACSDConnected)
                        {
                        LogInfo("UpdateBTMMRelayConnection: AWS_Disconnect");
                        AWACS_Disconnect();
                        AWACSDConnected = mDNSfalse;
                        }
                else LogInfo("UpdateBTMMRelayConnection: Not calling AWS_Disconnect");
                }
        }
#else
mDNSlocal void UpdateBTMMRelayConnection(mDNS *const m)
        {
        (void) m; // Unused
        LogInfo("UpdateBTMMRelayConnection: AWACS connection not started, no AWACS library");
        }
#endif // ! NO_AWACS
#endif // APPLE_OSX_mDNSResponder

// MUST be called holding the lock -- this routine calls SetupLocalAutoTunnelInterface_internal()
mDNSexport void SetDomainSecrets(mDNS *m)
        {
#ifdef NO_SECURITYFRAMEWORK
        (void)m;
        LogMsg("Note: SetDomainSecrets: no keychain support");
#else
        mDNSBool        haveAutoTunnels = mDNSfalse;

        LogInfo("SetDomainSecrets");

        // Rather than immediately deleting all keys now, we mark them for deletion in ten seconds.
        // In the case where the user simultaneously removes their DDNS host name and the key
        // for it, this gives mDNSResponder ten seconds to gracefully delete the name from the
        // server before it loses access to the necessary key. Otherwise, we'd leave orphaned
        // address records behind that we no longer have permission to delete.
        DomainAuthInfo *ptr;
        for (ptr = m->AuthInfoList; ptr; ptr = ptr->next)
                ptr->deltime = NonZeroTime(m->timenow + mDNSPlatformOneSecond*10);

#if APPLE_OSX_mDNSResponder
        {
        // Mark all TunnelClients for deletion
        ClientTunnel *client;
        for (client = m->TunnelClients; client; client = client->next)
                {
                LogInfo("SetDomainSecrets: tunnel to %##s marked for deletion", client->dstname.c);
                client->MarkedForDeletion = mDNStrue;
                }
        }
#endif // APPLE_OSX_mDNSResponder

        // String Array used to write list of private domains to Dynamic Store
        CFMutableArrayRef sa = CFArrayCreateMutable(NULL, 0, &kCFTypeArrayCallBacks);
        if (!sa) { LogMsg("SetDomainSecrets: CFArrayCreateMutable failed"); return; }
        CFIndex i;
        CFDataRef data = NULL;
        const int itemsPerEntry = 3; // domain name, key name, key value
        CFArrayRef secrets = NULL;
        int err = mDNSKeychainGetSecrets(&secrets);
        if (err || !secrets)
                LogMsg("SetDomainSecrets: mDNSKeychainGetSecrets failed error %d CFArrayRef %p", err, secrets);
        else
                {
                CFIndex ArrayCount = CFArrayGetCount(secrets);
                // Iterate through the secrets
                for (i = 0; i < ArrayCount; ++i)
                        {
                        int j;
                        CFArrayRef entry = CFArrayGetValueAtIndex(secrets, i);
                        if (CFArrayGetTypeID() != CFGetTypeID(entry) || itemsPerEntry != CFArrayGetCount(entry))
                                { LogMsg("SetDomainSecrets: malformed entry"); continue; }
                        for (j = 0; j < CFArrayGetCount(entry); ++j)
                                if (CFDataGetTypeID() != CFGetTypeID(CFArrayGetValueAtIndex(entry, j)))
                                        { LogMsg("SetDomainSecrets: malformed entry item"); continue; }

                        // The names have already been vetted by the helper, but checking them again here helps humans and automated tools verify correctness

                        // Get DNS domain this key is for
                        char stringbuf[MAX_ESCAPED_DOMAIN_NAME];        // Max legal domainname as C-string, including terminating NUL
                        data = CFArrayGetValueAtIndex(entry, 0);
                        if (CFDataGetLength(data) >= (int)sizeof(stringbuf))
                                { LogMsg("SetDomainSecrets: Bad kSecServiceItemAttr length %d", CFDataGetLength(data)); continue; }
                        CFDataGetBytes(data, CFRangeMake(0, CFDataGetLength(data)), (UInt8 *)stringbuf);
                        stringbuf[CFDataGetLength(data)] = '\0';

                        domainname domain;
                        if (!MakeDomainNameFromDNSNameString(&domain, stringbuf)) { LogMsg("SetDomainSecrets: bad key domain %s", stringbuf); continue; }

                        // Get key name
                        data = CFArrayGetValueAtIndex(entry, 1);
                        if (CFDataGetLength(data) >= (int)sizeof(stringbuf))
                                { LogMsg("SetDomainSecrets: Bad kSecAccountItemAttr length %d", CFDataGetLength(data)); continue; }
                        CFDataGetBytes(data, CFRangeMake(0,CFDataGetLength(data)), (UInt8 *)stringbuf);
                        stringbuf[CFDataGetLength(data)] = '\0';

                        domainname keyname;
                        if (!MakeDomainNameFromDNSNameString(&keyname, stringbuf)) { LogMsg("SetDomainSecrets: bad key name %s", stringbuf); continue; }

                        // Get key data
                        data = CFArrayGetValueAtIndex(entry, 2);
                        if (CFDataGetLength(data) >= (int)sizeof(stringbuf))
                                { LogMsg("SetDomainSecrets: Shared secret too long: %d", CFDataGetLength(data)); continue; }
                        CFDataGetBytes(data, CFRangeMake(0, CFDataGetLength(data)), (UInt8 *)stringbuf);
                        stringbuf[CFDataGetLength(data)] = '\0';        // mDNS_SetSecretForDomain requires NULL-terminated C string for key

                        DomainAuthInfo *FoundInList;
                        for (FoundInList = m->AuthInfoList; FoundInList; FoundInList = FoundInList->next)
                                if (SameDomainName(&FoundInList->domain, &domain)) break;

#if APPLE_OSX_mDNSResponder
                        if (FoundInList)
                                {
                                // If any client tunnel destination is in this domain, set deletion flag to false
                                ClientTunnel *client;
                                for (client = m->TunnelClients; client; client = client->next)
                                        if (FoundInList == GetAuthInfoForName_internal(m, &client->dstname))
                                        {
                                        LogInfo("SetDomainSecrets: tunnel to %##s no longer marked for deletion", client->dstname.c);
                                        client->MarkedForDeletion = mDNSfalse;
                                        }
                                }

#endif // APPLE_OSX_mDNSResponder

                        // Uncomment the line below to view the keys as they're read out of the system keychain
                        // DO NOT SHIP CODE THIS WAY OR YOU'LL LEAK SECRET DATA INTO A PUBLICLY READABLE FILE!
                        //LogInfo("SetDomainSecrets: %##s %##s %s", &domain.c, &keyname.c, stringbuf);

                        // If didn't find desired domain in the list, make a new entry
                        ptr = FoundInList;
                        if (FoundInList && FoundInList->AutoTunnel && haveAutoTunnels == mDNSfalse) haveAutoTunnels = mDNStrue;
                        if (!FoundInList)
                                {
                                ptr = (DomainAuthInfo*)mallocL("DomainAuthInfo", sizeof(*ptr));
                                if (!ptr) { LogMsg("SetDomainSecrets: No memory"); continue; }
                                }

                        LogInfo("SetDomainSecrets: %d of %d %##s", i, ArrayCount, &domain);
                        if (mDNS_SetSecretForDomain(m, ptr, &domain, &keyname, stringbuf, IsTunnelModeDomain(&domain)) == mStatus_BadParamErr)
                                {
                                if (!FoundInList) mDNSPlatformMemFree(ptr);             // If we made a new DomainAuthInfo here, and it turned out bad, dispose it immediately
                                continue;
                                }

#if APPLE_OSX_mDNSResponder
                        if (ptr->AutoTunnel) UpdateAutoTunnelDomainStatus(m, ptr);
#endif // APPLE_OSX_mDNSResponder

                        ConvertDomainNameToCString(&domain, stringbuf);
                        CFStringRef cfs = CFStringCreateWithCString(NULL, stringbuf, kCFStringEncodingUTF8);
                        if (cfs) { CFArrayAppendValue(sa, cfs); CFRelease(cfs); }
                        }
                CFRelease(secrets);
                }
        mDNSDynamicStoreSetConfig(kmDNSPrivateConfig, mDNSNULL, sa);
        CFRelease(sa);

#if APPLE_OSX_mDNSResponder
                {
                // clean up ClientTunnels
                ClientTunnel **pp = &m->TunnelClients;
                while (*pp)
                        {
                        if ((*pp)->MarkedForDeletion)
                                {
                                ClientTunnel *cur = *pp;
                                LogInfo("SetDomainSecrets: removing client %p %##s from list", cur, cur->dstname.c);
                                if (cur->q.ThisQInterval >= 0) mDNS_StopQuery(m, &cur->q);
                                AutoTunnelSetKeys(cur, mDNSfalse);
                                *pp = cur->next;
                                freeL("ClientTunnel", cur);
                                }
                        else
                                pp = &(*pp)->next;
                        }

                DomainAuthInfo *info = m->AuthInfoList;
                while (info)
                        {
                        if (info->AutoTunnel && info->deltime)
                                {
                                if (info->AutoTunnelNAT.clientContext)
                                        {
                                        // stop the NAT operation
                                        mDNS_StopNATOperation_internal(m, &info->AutoTunnelNAT);
                                        if (info->AutoTunnelNAT.clientCallback)
                                                {
                                                // Reset port and cleanup the state
                                                info->AutoTunnelNAT.ExternalAddress = m->ExternalAddress;
                                                info->AutoTunnelNAT.ExternalPort    = zeroIPPort;
                                                info->AutoTunnelNAT.RequestedPort    = zeroIPPort;
                                                info->AutoTunnelNAT.Lifetime        = 0;
                                                info->AutoTunnelNAT.Result          = mStatus_NoError;
                                                mDNS_DropLockBeforeCallback(); // Allow client to legally make mDNS API calls from the callback
                                                AutoTunnelDeleteAuthInfoState(m, info);
                                                mDNS_ReclaimLockAfterCallback(); // Decrement mDNS_reentrancy to block mDNS API calls again
                                                }
                                        info->AutoTunnelNAT.clientContext = mDNSNULL;
                                        }
                                RemoveAutoTunnelDomainStatus(m, info);
                                }
                        info = info->next;
                        }

                if (!haveAutoTunnels && !m->TunnelClients && m->AutoTunnelHostAddrActive)
                        {
                        // remove interface if no autotunnel servers and no more client tunnels
                        LogInfo("SetDomainSecrets: Bringing tunnel interface DOWN");
                        m->AutoTunnelHostAddrActive = mDNSfalse;
                        (void)mDNSAutoTunnelInterfaceUpDown(kmDNSDown, m->AutoTunnelHostAddr.b);
                        mDNSPlatformMemZero(m->AutoTunnelHostAddr.b, sizeof(m->AutoTunnelHostAddr.b));
                        }
                
                if (m->AutoTunnelHostAddr.b[0])
                        if (TunnelClients(m) || TunnelServers(m))
                                SetupLocalAutoTunnelInterface_internal(m, mDNSfalse);

                UpdateAnonymousRacoonConfig(m);         // Determine whether we need racoon to accept incoming connections
                UpdateBTMMRelayConnection(m);
                }
#endif // APPLE_OSX_mDNSResponder

        CheckSuppressUnusableQuestions(m);

#endif /* NO_SECURITYFRAMEWORK */
        }

mDNSlocal void SetLocalDomains(void)
        {
        CFMutableArrayRef sa = CFArrayCreateMutable(NULL, 0, &kCFTypeArrayCallBacks);
        if (!sa) { LogMsg("SetLocalDomains: CFArrayCreateMutable failed"); return; }

        CFArrayAppendValue(sa, CFSTR("local"));
        CFArrayAppendValue(sa, CFSTR("254.169.in-addr.arpa"));
        CFArrayAppendValue(sa, CFSTR("8.e.f.ip6.arpa"));
        CFArrayAppendValue(sa, CFSTR("9.e.f.ip6.arpa"));
        CFArrayAppendValue(sa, CFSTR("a.e.f.ip6.arpa"));
        CFArrayAppendValue(sa, CFSTR("b.e.f.ip6.arpa"));

        mDNSDynamicStoreSetConfig(kmDNSMulticastConfig, mDNSNULL, sa);
        CFRelease(sa);
        }

mDNSlocal void GetCurrentPMSetting(const CFStringRef name, mDNSs32 *val)
        {
#if USE_IOPMCOPYACTIVEPMPREFERENCES
        CFTypeRef blob = NULL;
        CFStringRef str = NULL;
        CFDictionaryRef odict = NULL;
        CFDictionaryRef idict = NULL;
        CFNumberRef number = NULL;

        blob = IOPSCopyPowerSourcesInfo();
        if (!blob) { LogMsg("GetCurrentPMSetting: IOPSCopyPowerSourcesInfo failed!"); goto end; }

        odict = IOPMCopyActivePMPreferences();
        if (!odict) { LogMsg("GetCurrentPMSetting: IOPMCopyActivePMPreferences failed!"); goto end; }

        str = IOPSGetProvidingPowerSourceType(blob);
        if (!str) { LogMsg("GetCurrentPMSetting: IOPSGetProvidingPowerSourceType failed!"); goto end; }

        idict = CFDictionaryGetValue(odict, str);
        if (!idict)
                {
                char buf[256];
                if (!CFStringGetCString(str, buf, sizeof(buf), kCFStringEncodingUTF8)) buf[0] = 0;
                LogMsg("GetCurrentPMSetting: CFDictionaryGetValue (%s) failed!", buf);
                goto end;
                }
        
        number = CFDictionaryGetValue(idict, name);
        if (!number || CFGetTypeID(number) != CFNumberGetTypeID() || !CFNumberGetValue(number, kCFNumberSInt32Type, val))
                *val = 0;
end:
        if (blob) CFRelease(blob);
        if (odict) CFRelease(odict);

#else

        SCDynamicStoreRef store = SCDynamicStoreCreate(NULL, CFSTR("mDNSResponder:GetCurrentPMSetting"), NULL, NULL);
        if (!store) LogMsg("GetCurrentPMSetting: SCDynamicStoreCreate failed: %s", SCErrorString(SCError()));
        else
                {
                CFDictionaryRef dict = SCDynamicStoreCopyValue(store, NetworkChangedKey_PowerSettings);
                if (!dict) LogSPS("GetCurrentPMSetting: Could not get IOPM CurrentSettings dict");
                else
                        {
                        CFNumberRef number = CFDictionaryGetValue(dict, name);
                        if (!number || CFGetTypeID(number) != CFNumberGetTypeID() || !CFNumberGetValue(number, kCFNumberSInt32Type, val))
                                *val = 0;
                        CFRelease(dict);
                        }
                CFRelease(store);
                }
        
#endif
        }

#if APPLE_OSX_mDNSResponder

static CFMutableDictionaryRef spsStatusDict = NULL;
static const CFStringRef kMetricRef = CFSTR("Metric");

mDNSlocal void SPSStatusPutNumber(CFMutableDictionaryRef dict, const mDNSu8* const ptr, CFStringRef key)
        {
        mDNSu8 tmp = (ptr[0] - '0') * 10 + ptr[1] - '0';
        CFNumberRef num = CFNumberCreate(NULL, kCFNumberSInt8Type, &tmp);
        if (!num)
                LogMsg("SPSStatusPutNumber: Could not create CFNumber");
        else
                {
                CFDictionarySetValue(dict, key, num);
                CFRelease(num);
                }
        }

mDNSlocal CFMutableDictionaryRef SPSCreateDict(const mDNSu8* const ptr)
        {
        CFMutableDictionaryRef dict = CFDictionaryCreateMutable(NULL, 0, &kCFTypeDictionaryKeyCallBacks, &kCFTypeDictionaryValueCallBacks);
        if (!dict) { LogMsg("SPSCreateDict: Could not create CFDictionary dict"); return dict; }
        
        char buffer[1024];
        buffer[mDNS_snprintf(buffer, sizeof(buffer), "%##s", ptr) - 1] = 0;
        CFStringRef spsname = CFStringCreateWithCString(NULL, buffer, kCFStringEncodingUTF8);
        if (!spsname) { LogMsg("SPSCreateDict: Could not create CFString spsname full"); CFRelease(dict); return NULL; }
        CFDictionarySetValue(dict, CFSTR("FullName"), spsname);
        CFRelease(spsname);

        if (ptr[0] >=  2) SPSStatusPutNumber(dict, ptr + 1, CFSTR("Type"));
        if (ptr[0] >=  5) SPSStatusPutNumber(dict, ptr + 4, CFSTR("Portability"));
        if (ptr[0] >=  8) SPSStatusPutNumber(dict, ptr + 7, CFSTR("MarginalPower"));
        if (ptr[0] >= 11) SPSStatusPutNumber(dict, ptr +10, CFSTR("TotalPower"));

        mDNSu32 tmp = SPSMetric(ptr);
        CFNumberRef num = CFNumberCreate(NULL, kCFNumberSInt32Type, &tmp);
        if (!num)
                LogMsg("SPSCreateDict: Could not create CFNumber");
        else
                {
                CFDictionarySetValue(dict, kMetricRef, num);
                CFRelease(num);
                }

        if (ptr[0] >= 12)
                {
                memcpy(buffer, ptr + 13, ptr[0] - 12);
                buffer[ptr[0] - 12] = 0;
                spsname = CFStringCreateWithCString(NULL, buffer, kCFStringEncodingUTF8);
                if (!spsname) { LogMsg("SPSCreateDict: Could not create CFString spsname"); CFRelease(dict); return NULL; }
                else
                        {
                        CFDictionarySetValue(dict, CFSTR("PrettyName"), spsname);
                        CFRelease(spsname);
                        }
                }
        
        return dict;
        }
        
mDNSlocal CFComparisonResult CompareSPSEntries(const void *val1, const void *val2, void *context)
        {
        (void)context;
        return CFNumberCompare((CFNumberRef)CFDictionaryGetValue((CFDictionaryRef)val1, kMetricRef),
                                                   (CFNumberRef)CFDictionaryGetValue((CFDictionaryRef)val2, kMetricRef),
                                                   NULL);
        }

mDNSlocal void UpdateSPSStatus(mDNS *const m, DNSQuestion *question, const ResourceRecord *const answer, QC_result AddRecord)
        {
        NetworkInterfaceInfo* info = (NetworkInterfaceInfo*)question->QuestionContext;
        debugf("UpdateSPSStatus: %s %##s %s %s", info->ifname, question->qname.c, AddRecord ? "Add" : "Rmv", answer ? RRDisplayString(m, answer) : "<null>");

        mDNS_Lock(m);
        mDNS_UpdateAllowSleep(m);
        mDNS_Unlock(m);

        if (answer && SPSMetric(answer->rdata->u.name.c) > 999999) return;      // Ignore instances with invalid names

        if (!spsStatusDict)
                {
                spsStatusDict = CFDictionaryCreateMutable(NULL, 0, &kCFTypeDictionaryKeyCallBacks, &kCFTypeDictionaryValueCallBacks);
                if (!spsStatusDict) { LogMsg("UpdateSPSStatus: Could not create CFDictionary spsStatusDict"); return; }
                }
        
        CFStringRef ifname = CFStringCreateWithCString(NULL, info->ifname, kCFStringEncodingUTF8);
        if (!ifname) { LogMsg("UpdateSPSStatus: Could not create CFString ifname"); return; }
        
        CFMutableArrayRef array = NULL;
        
        if (!CFDictionaryGetValueIfPresent(spsStatusDict, ifname, (const void**) &array))
                {
                array = CFArrayCreateMutable(NULL, 0, &kCFTypeArrayCallBacks);
                if (!array) { LogMsg("UpdateSPSStatus: Could not create CFMutableArray"); CFRelease(ifname); return; }
                CFDictionarySetValue(spsStatusDict, ifname, array);
                CFRelease(array); // let go of our reference, now that the dict has one
                }
        else
                if (!array) { LogMsg("UpdateSPSStatus: Could not get CFMutableArray for %s", info->ifname); CFRelease(ifname); return; }
        
        if (!answer) // special call that means the question has been stopped (because the interface is going away)
                CFArrayRemoveAllValues(array);
        else
                {
                CFMutableDictionaryRef dict = SPSCreateDict(answer->rdata->u.name.c);
                if (!dict) { CFRelease(ifname); return; }
                
                if (AddRecord)
                        {
                        if (!CFArrayContainsValue(array, CFRangeMake(0, CFArrayGetCount(array)), dict))
                                {
                                int i=0;
                                for (i=0; i<CFArrayGetCount(array); i++)
                                        if (CompareSPSEntries(CFArrayGetValueAtIndex(array, i), dict, NULL) != kCFCompareLessThan)
                                                break;
                                CFArrayInsertValueAtIndex(array, i, dict);
                                }
                        else LogMsg("UpdateSPSStatus: %s array already contains %##s", info->ifname, answer->rdata->u.name.c);
                        }
                else
                        {
                        CFIndex i = CFArrayGetFirstIndexOfValue(array, CFRangeMake(0, CFArrayGetCount(array)), dict);
                        if (i != -1) CFArrayRemoveValueAtIndex(array, i);
                        else LogMsg("UpdateSPSStatus: %s array does not contain %##s", info->ifname, answer->rdata->u.name.c);
                        }
                        
                CFRelease(dict);
                }

        if (!m->ShutdownTime) mDNSDynamicStoreSetConfig(kmDNSSleepProxyServersState, info->ifname, array);
        
        CFRelease(ifname);
        }

mDNSlocal mDNSs32 GetSystemSleepTimerSetting(void)
        {
        mDNSs32 val = -1;
        SCDynamicStoreRef store = SCDynamicStoreCreate(NULL, CFSTR("mDNSResponder:GetSystemSleepTimerSetting"), NULL, NULL);
        if (!store)
                LogMsg("GetSystemSleepTimerSetting: SCDynamicStoreCreate failed: %s", SCErrorString(SCError()));
        else
                {
                CFDictionaryRef dict = SCDynamicStoreCopyValue(store, NetworkChangedKey_PowerSettings);
                if (dict)
                        {
                        CFNumberRef number = CFDictionaryGetValue(dict, CFSTR("System Sleep Timer"));
                        if (number) CFNumberGetValue(number, kCFNumberSInt32Type, &val);
                        CFRelease(dict);
                        }
                CFRelease(store);
                }
        return val;
        }

mDNSlocal void SetSPS(mDNS *const m)
        {
        SCPreferencesSynchronize(m->p->SCPrefs);
        CFDictionaryRef dict = SCPreferencesGetValue(m->p->SCPrefs, CFSTR("NAT"));
        mDNSBool natenabled = (dict && (CFGetTypeID(dict) == CFDictionaryGetTypeID()) && DictionaryIsEnabled(dict));
        mDNSu8 sps = natenabled ? 50 : (OfferSleepProxyService && GetSystemSleepTimerSetting() == 0) ? OfferSleepProxyService : 0;

        // For devices that are not running NAT, but are set to never sleep, we may choose to act
        // as a Sleep Proxy, but only for non-portable Macs (Portability > 35 means nominal weight < 3kg)
        if (sps > 50 && SPMetricPortability > 35) sps = 0;

        // If we decide to let laptops act as Sleep Proxy, we should do it only when running on AC power, not on battery

        // For devices that are unable to sleep at all to save power (e.g. the current Apple TV hardware)
        // it makes sense for them to offer low-priority Sleep Proxy service on the network.
        // We rate such a device as metric 70 ("Incidentally Available Hardware")
        if (SPMetricMarginalPower == 10 && (!sps || sps > 70)) sps = 70;

        mDNSCoreBeSleepProxyServer(m, sps, SPMetricPortability, SPMetricMarginalPower, SPMetricTotalPower);
        }

mDNSlocal void InternetSharingChanged(SCPreferencesRef prefs, SCPreferencesNotification notificationType, void *context)
        {
        (void)prefs;             // Parameter not used
        (void)notificationType;  // Parameter not used
        mDNS *const m = (mDNS *const)context;
        KQueueLock(m);
        mDNS_Lock(m);

        // Tell platform layer to open or close its BPF fds
        if (!m->p->NetworkChanged ||
                m->p->NetworkChanged - NonZeroTime(m->timenow + mDNSPlatformOneSecond * 2) < 0)
                {
                m->p->NetworkChanged = NonZeroTime(m->timenow + mDNSPlatformOneSecond * 2);
                LogInfo("InternetSharingChanged: Set NetworkChanged to %d (%d)", m->p->NetworkChanged - m->timenow, m->p->NetworkChanged);
                }

        mDNS_Unlock(m);
        KQueueUnlock(m, "InternetSharingChanged");
        }

mDNSlocal mStatus WatchForInternetSharingChanges(mDNS *const m)
        {
        SCPreferencesRef SCPrefs = SCPreferencesCreate(NULL, CFSTR("mDNSResponder:WatchForInternetSharingChanges"), CFSTR("com.apple.nat.plist"));
        if (!SCPrefs) { LogMsg("SCPreferencesCreate failed: %s", SCErrorString(SCError())); return(mStatus_NoMemoryErr); }

        SCPreferencesContext context = { 0, m, NULL, NULL, NULL };
        if (!SCPreferencesSetCallback(SCPrefs, InternetSharingChanged, &context))
                { LogMsg("SCPreferencesSetCallback failed: %s", SCErrorString(SCError())); CFRelease(SCPrefs); return(mStatus_NoMemoryErr); }

#ifdef __LIB_DISPATCH__
        if (!SCPreferencesSetDispatchQueue( SCPrefs, dispatch_get_main_queue()))
                { LogMsg("SCPreferencesSetDispatchQueue failed: %s", SCErrorString(SCError())); return(mStatus_NoMemoryErr); }
#else
        if (!SCPreferencesScheduleWithRunLoop(SCPrefs, CFRunLoopGetCurrent(), kCFRunLoopDefaultMode))
                { LogMsg("SCPreferencesScheduleWithRunLoop failed: %s", SCErrorString(SCError())); CFRelease(SCPrefs); return(mStatus_NoMemoryErr); }
#endif

        m->p->SCPrefs = SCPrefs;
        return(mStatus_NoError);
        }

// The definitions below should eventually come from some externally-supplied header file.
// However, since these definitions can't really be changed without breaking binary compatibility,
// they should never change, so in practice it should not be a big problem to have them defined here.

#define mDNS_IOREG_KEY               "mDNS_KEY"
#define mDNS_IOREG_VALUE             "2009-07-30"
#define mDNS_USER_CLIENT_CREATE_TYPE 'mDNS'

enum
        {                                                       // commands from the daemon to the driver
    cmd_mDNSOffloadRR = 21,             // give the mdns update buffer to the driver
        };

typedef union { void *ptr; mDNSOpaque64 sixtyfourbits; } FatPtr;

typedef struct
        {                                   // cmd_mDNSOffloadRR structure
    uint32_t  command;                // set to OffloadRR
    uint32_t  rrBufferSize;           // number of bytes of RR records
    uint32_t  numUDPPorts;            // number of SRV UDP ports
    uint32_t  numTCPPorts;            // number of SRV TCP ports 
    uint32_t  numRRRecords;           // number of RR records
    uint32_t  compression;            // rrRecords - compression is base for compressed strings
    FatPtr    rrRecords;              // address of array of pointers to the rr records
    FatPtr    udpPorts;               // address of udp port list (SRV)
    FatPtr    tcpPorts;               // address of tcp port list (SRV)
        } mDNSOffloadCmd;

#include <IOKit/IOKitLib.h>
#include <dns_util.h>

mDNSlocal mDNSu16 GetPortArray(mDNS *const m, int trans, mDNSIPPort *portarray)
        {
        const domainlabel *const tp = (trans == mDNSTransport_UDP) ? (const domainlabel *)"\x4_udp" : (const domainlabel *)"\x4_tcp";
        int count = 0;
        AuthRecord *rr;
        for (rr = m->ResourceRecords; rr; rr=rr->next)
                if (rr->resrec.rrtype == kDNSType_SRV && SameDomainLabel(ThirdLabel(rr->resrec.name)->c, tp->c))
                        {
                        if (portarray) portarray[count] = rr->resrec.rdata->u.srv.port;
                        count++;
                        }

        // If Back to My Mac is on, also wake for packets to the IPSEC UDP port (4500)
        if (trans == mDNSTransport_UDP && TunnelServers(m))
                {
                LogSPS("GetPortArray Back to My Mac at %d", count);
                if (portarray) portarray[count] = IPSECPort;
                count++;
                }
        return(count);
        }

#define TfrRecordToNIC(RR) \
        (((RR)->resrec.InterfaceID && (RR)->resrec.InterfaceID != mDNSInterface_LocalOnly) || \
        (!(RR)->resrec.InterfaceID && ((RR)->ForceMCast || IsLocalDomain((RR)->resrec.name))))

mDNSlocal mDNSu32 CountProxyRecords(mDNS *const m, uint32_t *const numbytes)
        {
        *numbytes = 0;
        int count = 0;
        AuthRecord *rr;
        for (rr = m->ResourceRecords; rr; rr=rr->next)
                if (rr->resrec.RecordType > kDNSRecordTypeDeregistering)
                        if (TfrRecordToNIC(rr))
                                {
                                *numbytes += DomainNameLength(rr->resrec.name) + 10 + rr->resrec.rdestimate;
                                LogSPS("CountProxyRecords: %3d size %5d total %5d %s",
                                        count, DomainNameLength(rr->resrec.name) + 10 + rr->resrec.rdestimate, *numbytes, ARDisplayString(m,rr));
                                count++;
                                }
        return(count);
        }

mDNSlocal void GetProxyRecords(mDNS *const m, DNSMessage *const msg, uint32_t *const numbytes, FatPtr *const records)
        {
        mDNSu8 *p = msg->data;
        const mDNSu8 *const limit = p + *numbytes;
        InitializeDNSMessage(&msg->h, zeroID, zeroID);

        int count = 0;
        AuthRecord *rr;
        for (rr = m->ResourceRecords; rr; rr=rr->next)
                if (rr->resrec.RecordType > kDNSRecordTypeDeregistering)
                        if (TfrRecordToNIC(rr))
                                {
                                records[count].sixtyfourbits = zeroOpaque64;
                                records[count].ptr = p;
                                if (rr->resrec.RecordType & kDNSRecordTypeUniqueMask)
                                        rr->resrec.rrclass |= kDNSClass_UniqueRRSet;    // Temporarily set the 'unique' bit so PutResourceRecord will set it
                                p = PutResourceRecordTTLWithLimit(msg, p, &msg->h.mDNS_numUpdates, &rr->resrec, rr->resrec.rroriginalttl, limit);
                                rr->resrec.rrclass &= ~kDNSClass_UniqueRRSet;           // Make sure to clear 'unique' bit back to normal state
                                LogSPS("GetProxyRecords: %3d start %p end %p size %5d total %5d %s",
                                        count, records[count].ptr, p, p - (mDNSu8 *)records[count].ptr, p - msg->data, ARDisplayString(m,rr));
                                count++;
                                }
        *numbytes = p - msg->data;
        }

// If compiling with old headers and libraries (pre 10.5) that don't include IOConnectCallStructMethod
// then we declare a dummy version here so that the code at least compiles
#ifndef AVAILABLE_MAC_OS_X_VERSION_10_5_AND_LATER
static kern_return_t
IOConnectCallStructMethod(
        mach_port_t      connection,            // In
        uint32_t         selector,                      // In
        const void      *inputStruct,           // In
        size_t           inputStructCnt,        // In
        void            *outputStruct,          // Out
        size_t          *outputStructCnt)       // In/Out
        {
        (void)connection;
        (void)selector;
        (void)inputStruct;
        (void)inputStructCnt;
        (void)outputStruct;
        (void)outputStructCnt;
        LogMsg("Compiled without IOConnectCallStructMethod");
        return(KERN_FAILURE);
        }
#endif

mDNSexport mStatus ActivateLocalProxy(mDNS *const m, char *ifname)      // Called with the lock held
        {
        mStatus result = mStatus_UnknownErr;
        io_service_t service = IOServiceGetMatchingService(kIOMasterPortDefault, IOBSDNameMatching(kIOMasterPortDefault, 0, ifname));
        if (!service) { LogMsg("ActivateLocalProxy: No service for interface %s", ifname); return(mStatus_UnknownErr); }

        io_name_t n1, n2;
        IOObjectGetClass(service, n1);
        io_object_t parent;
        kern_return_t kr = IORegistryEntryGetParentEntry(service, kIOServicePlane, &parent);
        if (kr != KERN_SUCCESS) LogMsg("ActivateLocalProxy: IORegistryEntryGetParentEntry for %s/%s failed %d", ifname, n1, kr);
        else
                {
                IOObjectGetClass(parent, n2);
                LogSPS("ActivateLocalProxy: Interface %s service %s parent %s", ifname, n1, n2);
                const CFTypeRef ref = IORegistryEntryCreateCFProperty(parent, CFSTR(mDNS_IOREG_KEY), kCFAllocatorDefault, mDNSNULL);
                if (!ref) LogSPS("ActivateLocalProxy: No mDNS_IOREG_KEY for interface %s/%s/%s", ifname, n1, n2);
                else
                        {
                        if (CFGetTypeID(ref) != CFStringGetTypeID() || !CFEqual(ref, CFSTR(mDNS_IOREG_VALUE)))
                                LogMsg("ActivateLocalProxy: mDNS_IOREG_KEY for interface %s/%s/%s value %s != %s",
                                        ifname, n1, n2, CFStringGetCStringPtr(ref, mDNSNULL), mDNS_IOREG_VALUE);
                        else
                                {
                                io_connect_t conObj;
                                kr = IOServiceOpen(parent, mach_task_self(), mDNS_USER_CLIENT_CREATE_TYPE, &conObj);
                                if (kr != KERN_SUCCESS) LogMsg("ActivateLocalProxy: IOServiceOpen for %s/%s/%s failed %d", ifname, n1, n2, kr);
                                else
                                        {
                                        mDNSOffloadCmd cmd;
                                        mDNSPlatformMemZero(&cmd, sizeof(cmd)); // When compiling 32-bit, make sure top 32 bits of 64-bit pointers get initialized to zero
                                        cmd.command       = cmd_mDNSOffloadRR;
                                        cmd.numUDPPorts   = GetPortArray(m, mDNSTransport_UDP, mDNSNULL);
                                        cmd.numTCPPorts   = GetPortArray(m, mDNSTransport_TCP, mDNSNULL);
                                        cmd.numRRRecords  = CountProxyRecords(m, &cmd.rrBufferSize);
                                        cmd.compression   = sizeof(DNSMessageHeader);

                                        DNSMessage *msg = (DNSMessage *)mallocL("mDNSOffloadCmd msg", sizeof(DNSMessageHeader) + cmd.rrBufferSize);
                                        cmd.rrRecords.ptr = mallocL("mDNSOffloadCmd rrRecords", cmd.numRRRecords * sizeof(FatPtr));
                                        cmd.udpPorts .ptr = mallocL("mDNSOffloadCmd udpPorts",  cmd.numUDPPorts  * sizeof(mDNSIPPort));
                                        cmd.tcpPorts .ptr = mallocL("mDNSOffloadCmd tcpPorts",  cmd.numTCPPorts  * sizeof(mDNSIPPort));

                                        LogSPS("ActivateLocalProxy: msg %p %d RR %p %d, UDP %p %d, TCP %p %d",
                                                msg, cmd.rrBufferSize,
                                                cmd.rrRecords.ptr, cmd.numRRRecords,
                                                cmd.udpPorts .ptr, cmd.numUDPPorts,
                                                cmd.tcpPorts .ptr, cmd.numTCPPorts);

                                        if (!msg || !cmd.rrRecords.ptr || !cmd.udpPorts.ptr || !cmd.tcpPorts.ptr)
                                                LogMsg("ActivateLocalProxy: Failed to allocate memory: msg %p %d RR %p %d, UDP %p %d, TCP %p %d",
                                                msg, cmd.rrBufferSize,
                                                cmd.rrRecords.ptr, cmd.numRRRecords,
                                                cmd.udpPorts .ptr, cmd.numUDPPorts,
                                                cmd.tcpPorts .ptr, cmd.numTCPPorts);
                                        else
                                                {
                                                GetProxyRecords(m, msg, &cmd.rrBufferSize, cmd.rrRecords.ptr);
                                                GetPortArray(m, mDNSTransport_UDP, cmd.udpPorts.ptr);
                                                GetPortArray(m, mDNSTransport_TCP, cmd.tcpPorts.ptr);
                                                char outputData[2];
                                                size_t outputDataSize = sizeof(outputData);
                                                kr = IOConnectCallStructMethod(conObj, 0, &cmd, sizeof(cmd), outputData, &outputDataSize);
                                                LogSPS("ActivateLocalProxy: IOConnectCallStructMethod for %s/%s/%s %d", ifname, n1, n2, kr);
                                                if (kr == KERN_SUCCESS) result = mStatus_NoError;
                                                }

                                        if (cmd.tcpPorts. ptr) freeL("mDNSOffloadCmd udpPorts",  cmd.tcpPorts .ptr);
                                        if (cmd.udpPorts. ptr) freeL("mDNSOffloadCmd tcpPorts",  cmd.udpPorts .ptr);
                                        if (cmd.rrRecords.ptr) freeL("mDNSOffloadCmd rrRecords", cmd.rrRecords.ptr);
                                        if (msg)               freeL("mDNSOffloadCmd msg",       msg);
                                        IOServiceClose(conObj);
                                        }
                                }
                        CFRelease(ref);
                        }
                IOObjectRelease(parent);
                }
        IOObjectRelease(service);
        return result;
        }

#endif // APPLE_OSX_mDNSResponder

static io_service_t g_rootdomain = MACH_PORT_NULL;

mDNSlocal mDNSBool SystemWakeForNetworkAccess(void)
        {
        mDNSs32 val = 0;
        CFBooleanRef clamshellStop = NULL;
        mDNSBool retnow = mDNSfalse;

        if (DisableSleepProxyClient) { LogSPS("SystemWakeForNetworkAccess: Sleep Proxy Client disabled by command-line option"); return mDNSfalse; }

        GetCurrentPMSetting(CFSTR("Wake On LAN"), &val);
        LogSPS("SystemWakeForNetworkAccess: Wake On LAN: %d", val);
        if (!val) return mDNSfalse;
        
        if (!g_rootdomain) g_rootdomain = IORegistryEntryFromPath(MACH_PORT_NULL, kIOPowerPlane ":/IOPowerConnection/IOPMrootDomain");
        if (!g_rootdomain) { LogMsg("SystemWakeForNetworkAccess: IORegistryEntryFromPath failed; assuming no clamshell so can WOMP"); return mDNStrue; }
        
        clamshellStop = (CFBooleanRef)IORegistryEntryCreateCFProperty(g_rootdomain, CFSTR(kAppleClamshellStateKey), kCFAllocatorDefault, 0);
        if (!clamshellStop) { LogSPS("SystemWakeForNetworkAccess: kAppleClamshellStateKey does not exist; assuming no clamshell so can WOMP"); return mDNStrue; }
        retnow = clamshellStop == kCFBooleanFalse;
        CFRelease(clamshellStop);
        if (retnow) { LogSPS("SystemWakeForNetworkAccess: kAppleClamshellStateKey is false; clamshell is open so can WOMP"); return mDNStrue; }
        
        clamshellStop = (CFBooleanRef)IORegistryEntryCreateCFProperty(g_rootdomain, CFSTR(kAppleClamshellCausesSleepKey), kCFAllocatorDefault, 0);
        if (!clamshellStop) { LogSPS("SystemWakeForNetworkAccess: kAppleClamshellCausesSleepKey does not exist; assuming no clamshell so can WOMP"); return mDNStrue; }
        retnow = (clamshellStop == kCFBooleanFalse);
        CFRelease(clamshellStop);
        if (retnow) { LogSPS("SystemWakeForNetworkAccess: kAppleClamshellCausesSleepKey is false; clamshell is closed but can WOMP"); return mDNStrue; }
        
        LogSPS("SystemWakeForNetworkAccess: clamshell is closed and can't WOMP");
        return mDNSfalse;
        }

mDNSlocal mDNSBool SystemSleepOnlyIfWakeOnLAN(void)
        {
        mDNSs32 val = 0;
        GetCurrentPMSetting(CFSTR("Idle Sleep Requires Network Proxy"), &val);
        return val != 0 ? mDNStrue : mDNSfalse;
        }

#if APPLE_OSX_mDNSResponder
// If the _autotunnel6 record is still there in the list, we are waiting for the ack from
// the server.
//
// If we are behind a double-NAT or NAT with no NAT-PMP support, we should make sure that all our
// BTMM records are deregistered so that it does not appear on the Finder sidebar of our peers
// when we go to sleep. First _autotunnel6 and the host record gets deregistered, then SRV
// (UpdateAllSrvRecords) and then PTR and TXT
//
// Note: We wait up to a maximum of 10 seconds before we ack the sleep. So, returning "false"
// here does not necessarily mean that it will be honored.
mDNSexport mDNSBool RecordReadyForSleep(mDNS *const m, AuthRecord *rr)
        {
        if (!AuthRecord_uDNS(rr)) return mDNStrue;

        if (SameDomainLabel(rr->namestorage.c, (const mDNSu8 *)"\x0c_autotunnel6"))
                {
                LogInfo("RecordReadyForSleep: %s not ready for sleep", ARDisplayString(m, rr));
                return mDNSfalse;
                }
        // Just check for the SRV record alone as the PTR and TXT records are dependent on SRV
        // and will get deregistered together in a single update. We also don't check for TXT
        // records  as _kerberos TXT record is always there even when there are no services
        // and we don't want to delay the sleep in that case.
        if (mDNSIPPortIsZero(m->LLQNAT.ExternalPort) || m->LLQNAT.Result)
                {
                if ((rr->resrec.rrtype == kDNSType_SRV) && rr->state != regState_NoTarget && rr->zone)
                        {
                        DomainAuthInfo *info = GetAuthInfoForName_internal(m, rr->zone);
                        if (info && info->AutoTunnel)
                                {       
                                LogInfo("RecordReadyForSleep: %s not ready for sleep", ARDisplayString(m, rr));
                                return mDNSfalse;
                                }
                        }
                }
        return mDNStrue;
        }

// Note: BTMMDict needs to be retained by the caller if needed
mDNSlocal CFDictionaryRef ParseBackToMyMacKey(CFDictionaryRef connd)
        {
        CFDictionaryRef BTMMDict = CFDictionaryGetValue(connd, CFSTR("BackToMyMac"));
        if (!BTMMDict)
                {
                LogInfo("ParseBackToMyMacKey: CFDictionaryGetValue No value for BackToMyMac");
                return NULL;
                }

        // Non-dictionary is treated as non-existent dictionary
        if (CFGetTypeID(BTMMDict) != CFDictionaryGetTypeID())
                {LogMsg("ERROR: ParseBackToMyMacKey: CFDictionaryGetValue BackToMyMac not a dictionary"); CFRelease(BTMMDict); return NULL;}

        return BTMMDict;
        }

mDNSlocal void ParseBTMMInterfaceKey(CFDictionaryRef BTMMDict, char *buf, int buflen)
        {
        CFTypeRef string;
        mDNSBool ifExists;

        ifExists = CFDictionaryGetValueIfPresent(BTMMDict, CFSTR("Interface"), &string);
        if (ifExists)
                {
                if (!CFStringGetCString(string, buf, buflen, kCFStringEncodingUTF8))
                        {
                        LogMsg("ERROR: ParseBTMMInterfaceKey: Could not convert Interface to CString");
                        if (buflen) buf[0] = 0;
                        return;
                        }
                else
                        debugf("ParseBTMMInterfaceKey: Interface Key exists %s", buf);
                }
        else
                {
                if (buflen) buf[0] = 0;
                debugf("ParseBTMMInterfaceKey: Interface Key does not exist");
                }
        }

mDNSexport void RemoveAutoTunnel6Record(mDNS *const m)
        {
        DomainAuthInfo *info;
        char buf[IFNAMSIZ];

        // Did we parse a non-empty dictionary before ?
        if (!m->p->ConndBTMMDict || (CFDictionaryGetCount(m->p->ConndBTMMDict) == 0))
                {
                LogInfo("RemoveAutoTunnel6Record: Never registered any records before, not deregistering %p", m->p->ConndBTMMDict);
                return;
                }

        // Did we have a non-NULL Interface name before ?
        ParseBTMMInterfaceKey(m->p->ConndBTMMDict, buf, sizeof(buf));
        if (!strlen(buf))
                {
                LogInfo("RemoveAutoTunnel6Record: Interface name already NULL, not deregistering");
                return;
                }
                
        // Set the address to zero before calling DeregisterAutoTunnel6Record. If we call
        // Deregister too quickly before the previous Register completed (just scheduled
        // to be sent out) and when DeregisterAutoTunnel6Record calls mDNS_Register_internal,
        // it invokes the AutoTunnelRecordCallback immediately and AutoTunnelRelayAddr should
        // be zero so that we don't register again.
        m->AutoTunnelRelayAddr = zerov6Addr;
        if (!m->AuthInfoList) LogInfo("RemoveAutoTunnel6Record: No Domain AuthInfo");
        for (info = m->AuthInfoList; info; info = info->next)
                {
                if (!info->AutoTunnel) { LogInfo("RemoveAutoTunnel6Record: Domain %##s not an AutoTunnel", info->domain.c); continue;}

                if (info->deltime) {LogInfo("RemoveAutoTunnel6Record: Domain %##s about to be deleted", info->domain.c); continue;}

                LogInfo("RemoveAutoTunnel6Record: Deregistering records for domain %##s", info->domain.c);
                DeregisterAutoTunnel6Record(m, info);
                }
        CFRelease(m->p->ConndBTMMDict);
        m->p->ConndBTMMDict = NULL;
        }

// Returns zero on success
mDNSlocal int GetIPv6AddressForIfname(char *ifname, mDNSv6Addr *ipv6Addr)
        {
        struct ifaddrs  *ifa;
        struct ifaddrs  *ifaddrs;
        mDNSAddr addr;

        if (if_nametoindex(ifname) == 0) {LogInfo("GetIPv6AddressForIfname: Invalid name %s", ifname); return (-1);}

        if (getifaddrs(&ifaddrs) < 0) {LogInfo("GetIPv6AddressForIfname: getifaddrs failed"); return (-1);}

        /*
         * Find the ifaddr entry corresponding to the interface name,
         * and return the first matching non-linklocal IPv6 address.
         */
        for (ifa = ifaddrs; ifa != NULL; ifa = ifa->ifa_next)
                {
                if (strncmp(ifa->ifa_name, ifname, IFNAMSIZ) != 0)
                        continue;
                if (ifa->ifa_flags & IFF_UP && ifa->ifa_addr && ifa->ifa_addr->sa_family == AF_INET6)
                        {
                        struct sockaddr_in6 *ifa_addr = (struct sockaddr_in6 *)ifa->ifa_addr;
                        if (IN6_IS_ADDR_LINKLOCAL(&ifa_addr->sin6_addr))
                                continue;
                        if (SetupAddr(&addr, ifa->ifa_addr) != mStatus_NoError)
                                {
                                LogInfo("GetIPv6AddressForIfname: SetupAddr error, continuing to the next address");
                                continue;
                                }
                        else
                                {
                                *ipv6Addr = *(mDNSv6Addr *)&addr.ip.v6;
                                LogInfo("GetIPv6AddressForIfname: Returning IPv6 address %.16a", ipv6Addr);
                                freeifaddrs(ifaddrs);
                                return 0;
                                }
                        }
       }
        LogInfo("GetIPv6AddressForIfname: No Valid IPv6 address");
        freeifaddrs(ifaddrs);
        return (-1);
        }

mDNSlocal void AddAutoTunnel6Record(mDNS *const m, char *ifname, CFDictionaryRef BTMMDict)
        {
        mDNSv6Addr v6addr;
        DomainAuthInfo *info;

        if (GetIPv6AddressForIfname(ifname, &v6addr) != 0)
                {
                LogInfo("AddAutoTunnel6Record: No Valid IPv6 addresses found for %s", ifname);
                // If the interface does not exist but the dictionary has the value, we treat
                // this case as though the dictionary does not have the value
                RemoveAutoTunnel6Record(m);
                // If awacsd crashes or exits for some reason, restart the relay connection
                UpdateBTMMRelayConnection(m);
                return;
                }
        
        m->AutoTunnelRelayAddr = v6addr;

        if (!m->AuthInfoList) LogInfo("AddAutoTunnel6Record: No Domain AuthInfo");
        for (info = m->AuthInfoList; info; info = info->next)
                {
                // clientContext for a domain tells us that we are listening for at least one Service/Record
                // in a domain and SetLocalAutoTunnelInterface_internal was called
                if (!info->AutoTunnel) { LogInfo("AddAutoTunnel6Record: Domain %##s not an AutoTunnel", info->domain.c); continue;}

                if (!info->AutoTunnelNAT.clientContext) {LogInfo("AddAutoTunnel6Record: Domain %##s has no services", info->domain.c); continue;}

                if (info->deltime) {LogInfo("AddAutoTunnel6Record: Domain %##s about to be deleted", info->domain.c); continue;}

                LogInfo("AddAutoTunnel6Record: Registering records for domain %##s", info->domain.c);
                mDNS_Lock(m);
                RegisterAutoTunnel6Record(m, info);
                mDNS_Unlock(m);
                }
        if (m->p->ConndBTMMDict) CFRelease(m->p->ConndBTMMDict);
        m->p->ConndBTMMDict = CFRetain(BTMMDict);
        }

mDNSlocal void ParseBackToMyMac(mDNS *const m, CFDictionaryRef connd)
        {
        CFDictionaryRef BTMMDict;
        char buf[IFNAMSIZ];

        BTMMDict = ParseBackToMyMacKey(connd);
        if (!BTMMDict)
                {
                LogInfo("ParseBackToMyMac: CFDictionaryGetValue No value for BackToMyMac, Removing autotunnel6");
                RemoveAutoTunnel6Record(m);
                return;
                }

        ParseBTMMInterfaceKey(BTMMDict, buf, sizeof(buf));
        if (!strlen(buf))
                {
                LogInfo("ParseBackToMyMac: NULL value for Interface, Removing autotunnel6"); 
                RemoveAutoTunnel6Record(m);
                // We don't have a utun interface, start the relay connection if possible
                UpdateBTMMRelayConnection(m);
                }
        else
                {
                LogInfo("ParseBackToMyMac: non-NULL value for Interface, Adding autotunnel6"); 
                AddAutoTunnel6Record(m, buf, BTMMDict);
                }
        }

mDNSexport void SetupConndConfigChanges(mDNS *const m)
        {
        CFDictionaryRef connd;
        SCDynamicStoreRef store;

        store = SCDynamicStoreCreate(NULL, CFSTR("mDNSResponder:SetupConndConfigChanges"), NULL, NULL);
        if (!store) {LogMsg("SetupConndConfigChanges: SCDynamicStoreCreate failed: %s", SCErrorString(SCError())); return;}

        connd = SCDynamicStoreCopyValue(store, NetworkChangedKey_BTMMConnectivity);
        if (!connd)
                {LogInfo("SetupConndConfigChanges: SCDynamicStoreCopyValue failed: %s", SCErrorString(SCError())); CFRelease(store); return;}
        else
                {
                ParseBackToMyMac(m, connd);
                }
        CFRelease(connd);
        CFRelease(store);
        }
#endif /* APPLE_OSX_mDNSResponder */

                
mDNSexport void mDNSMacOSXNetworkChanged(mDNS *const m)
        {
        LogInfo("***   Network Configuration Change   ***  (%d)%s",
                m->p->NetworkChanged ? mDNS_TimeNow(m) - m->p->NetworkChanged : 0,
                m->p->NetworkChanged ? "" : " (no scheduled configuration change)");
        m->p->NetworkChanged = 0;               // If we received a network change event and deferred processing, we're now dealing with it
        mDNSs32 utc = mDNSPlatformUTC();
        m->SystemWakeOnLANEnabled = SystemWakeForNetworkAccess();
        m->SystemSleepOnlyIfWakeOnLAN = SystemSleepOnlyIfWakeOnLAN();
        MarkAllInterfacesInactive(m, utc);
        UpdateInterfaceList(m, utc);
        ClearInactiveInterfaces(m, utc);
        SetupActiveInterfaces(m, utc);

#if APPLE_OSX_mDNSResponder

        SetupConndConfigChanges(m);

        if (m->AutoTunnelHostAddr.b[0])
                {
                mDNS_Lock(m);
                if (TunnelClients(m) || TunnelServers(m))
                        SetupLocalAutoTunnelInterface_internal(m, mDNSfalse);
                mDNS_Unlock(m);
                }
        
        // Scan to find client tunnels whose questions have completed,
        // but whose local inner/outer addresses have changed since the tunnel was set up
        ClientTunnel *p;
        for (p = m->TunnelClients; p; p = p->next)
                if (p->q.ThisQInterval < 0)
                        {
                        if (!mDNSIPPortIsZero(p->rmt_outer_port))
                                {
                                mDNSAddr tmpSrc = zeroAddr;
                                mDNSAddr tmpDst = { mDNSAddrType_IPv4, {{{0}}} };
                                tmpDst.ip.v4 = p->rmt_outer;
                                mDNSPlatformSourceAddrForDest(&tmpSrc, &tmpDst);
                                if (!mDNSSameIPv6Address(p->loc_inner, m->AutoTunnelHostAddr) ||
                                        !mDNSSameIPv4Address(p->loc_outer, tmpSrc.ip.v4))
                                        {
                                        AutoTunnelSetKeys(p, mDNSfalse);
                                        p->loc_inner = m->AutoTunnelHostAddr;
                                        p->loc_outer = tmpSrc.ip.v4;
                                        AutoTunnelSetKeys(p, mDNStrue);
                                        }
                                }
                                else
                                        {
                                        if (!mDNSSameIPv6Address(p->loc_inner, m->AutoTunnelHostAddr) ||
                                                !mDNSSameIPv6Address(p->loc_outer6, m->AutoTunnelRelayAddr))
                                                {
                                                AutoTunnelSetKeys(p, mDNSfalse);
                                                p->loc_inner = m->AutoTunnelHostAddr;
                                                p->loc_outer6 = m->AutoTunnelRelayAddr;
                                                AutoTunnelSetKeys(p, mDNStrue);
                                                }
                                        }
                        }


        SetSPS(m);

        NetworkInterfaceInfoOSX *i;
        for (i = m->p->InterfaceList; i; i = i->next)
                {
                if (!m->SPSSocket)              // Not being Sleep Proxy Server; close any open BPF fds
                        {
                        if (i->BPF_fd >= 0 && CountProxyTargets(m, i, mDNSNULL, mDNSNULL) == 0) CloseBPF(i);
                        }
                else                                                            // else, we're Sleep Proxy Server; open BPF fds
                        {
                        if (i->Exists && i->Registered == i && i->ifinfo.McastTxRx && !(i->ifa_flags & IFF_LOOPBACK) && i->BPF_fd == -1)
                                { LogSPS("%s requesting BPF", i->ifinfo.ifname); i->BPF_fd = -2; mDNSRequestBPF(); }
                        }
                }

#endif // APPLE_OSX_mDNSResponder

        uDNS_SetupDNSConfig(m);
        mDNS_ConfigChanged(m);
        }

// Called with KQueueLock & mDNS lock
mDNSlocal void SetNetworkChanged(mDNS *const m, mDNSs32 delay)
        {
        if (!m->p->NetworkChanged || m->p->NetworkChanged - NonZeroTime(m->timenow + delay) < 0)
                {
                m->p->NetworkChanged = NonZeroTime(m->timenow + delay);
                LogInfo("SetNetworkChanged: setting network changed to %d (%d)", delay, m->p->NetworkChanged);
                }
        }


// Copy the fourth slash-delimited element from either:
//   State:/Network/Interface/<bsdname>/IPv4
// or
//   Setup:/Network/Service/<servicename>/Interface
mDNSlocal CFStringRef CopyNameFromKey(CFStringRef key)
        {
        CFArrayRef a;
        CFStringRef name = NULL;

        a = CFStringCreateArrayBySeparatingStrings(NULL, key, CFSTR("/"));
        if (a && CFArrayGetCount(a) == 5) name = CFRetain(CFArrayGetValueAtIndex(a, 3));
        if (a != NULL) CFRelease(a);

        return name;
        }

// Whether a key from a network change notification corresponds to
// an IP service that is explicitly configured for IPv4 Link Local
mDNSlocal mDNSBool ChangedKeysHaveIPv4LL(CFArrayRef inkeys)
        {
        SCDynamicStoreRef store = NULL;
        CFDictionaryRef dict = NULL;
        CFMutableArrayRef a;
        const void **keys = NULL, **vals = NULL;
        CFStringRef pattern = NULL;
        int i, ic, j, jc;
        mDNSBool found = mDNSfalse;
        
        jc = CFArrayGetCount(inkeys);
        if (!jc) goto done;

        store = SCDynamicStoreCreate(NULL, CFSTR("mDNSResponder:ChangedKeysHaveIPv4LL"), NULL, NULL);
        if (store == NULL) goto done;

        a = CFArrayCreateMutable(NULL, 0, &kCFTypeArrayCallBacks);
        if (a == NULL) goto done;

        // Setup:/Network/Service/[^/]+/Interface
        pattern = SCDynamicStoreKeyCreateNetworkServiceEntity(NULL, kSCDynamicStoreDomainSetup, kSCCompAnyRegex, kSCEntNetInterface);
        if (pattern == NULL) goto done;
        CFArrayAppendValue(a, pattern);
        CFRelease(pattern);

        // Setup:/Network/Service/[^/]+/IPv4
        pattern = SCDynamicStoreKeyCreateNetworkServiceEntity(NULL, kSCDynamicStoreDomainSetup, kSCCompAnyRegex, kSCEntNetIPv4);
        if (pattern == NULL) goto done;
        CFArrayAppendValue(a, pattern);
        CFRelease(pattern);

        dict = SCDynamicStoreCopyMultiple(store, NULL, a);
        CFRelease(a);

        if (!dict)
                {
                LogMsg("ChangedKeysHaveIPv4LL: Empty dictionary");
                goto done;
                }

        ic = CFDictionaryGetCount(dict);
        vals = mDNSPlatformMemAllocate(sizeof (void *) * ic);
        keys = mDNSPlatformMemAllocate(sizeof (void *) * ic);
        CFDictionaryGetKeysAndValues(dict, keys, vals);
        
        for (j = 0; j < jc && !found; j++)
                {
                CFStringRef key = CFArrayGetValueAtIndex(inkeys, j);
                CFStringRef ifname = NULL;

                char buf[256];

                // It would be nice to use a regex here
                if (!CFStringHasPrefix(key, CFSTR("State:/Network/Interface/")) || !CFStringHasSuffix(key, kSCEntNetIPv4)) continue;
                
                if ((ifname = CopyNameFromKey(key)) == NULL) continue;
                if (mDNS_LoggingEnabled)
                        {
                        if (!CFStringGetCString(ifname, buf, sizeof(buf), kCFStringEncodingUTF8)) buf[0] = 0;
                        LogInfo("ChangedKeysHaveIPv4LL: potential ifname %s", buf);
                        }

                for (i = 0; i < ic; i++)
                        {
                        CFDictionaryRef ipv4dict;
                        CFStringRef name;
                        CFStringRef serviceid;
                        CFStringRef configmethod;
                        
                        if (!CFStringHasSuffix(keys[i], kSCEntNetInterface)) continue;
                        
                        if (CFDictionaryGetTypeID() != CFGetTypeID(vals[i])) continue;
        
                        if ((name = CFDictionaryGetValue(vals[i], kSCPropNetInterfaceDeviceName)) == NULL) continue;
        
                        if (!CFEqual(ifname, name)) continue;
                        
                        if ((serviceid = CopyNameFromKey(keys[i])) == NULL) continue;
                        if (mDNS_LoggingEnabled)
                                {
                                if (!CFStringGetCString(serviceid, buf, sizeof(buf), kCFStringEncodingUTF8)) buf[0] = 0;
                                LogInfo("ChangedKeysHaveIPv4LL: found serviceid %s", buf);
                                }
                        
                        pattern = SCDynamicStoreKeyCreateNetworkServiceEntity(NULL, kSCDynamicStoreDomainSetup, serviceid, kSCEntNetIPv4);
                        CFRelease(serviceid);
                        if (pattern == NULL) continue;
                        
                        ipv4dict = CFDictionaryGetValue(dict, pattern);
                        CFRelease(pattern);
                        if (!ipv4dict || CFDictionaryGetTypeID() != CFGetTypeID(ipv4dict)) continue;
                        
                        configmethod = CFDictionaryGetValue(ipv4dict, kSCPropNetIPv4ConfigMethod);
                        if (!configmethod) continue;

                        if (mDNS_LoggingEnabled)
                                {
                                if (!CFStringGetCString(configmethod, buf, sizeof(buf), kCFStringEncodingUTF8)) buf[0] = 0;
                                LogInfo("ChangedKeysHaveIPv4LL: configmethod %s", buf);
                                }
                                
                        if (CFEqual(configmethod, kSCValNetIPv4ConfigMethodLinkLocal)) { found = mDNStrue; break; }
                        }
                
                CFRelease(ifname);
                }

        done:
        if (vals != NULL) mDNSPlatformMemFree(vals);
        if (keys != NULL) mDNSPlatformMemFree(keys);
        if (dict != NULL) CFRelease(dict);
        if (store != NULL) CFRelease(store);

        return found;
        }

mDNSlocal void NetworkChanged(SCDynamicStoreRef store, CFArrayRef changedKeys, void *context)
        {
        (void)store;        // Parameter not used
        mDNS *const m = (mDNS *const)context;
        KQueueLock(m);
        mDNS_Lock(m);

        mDNSs32 delay = mDNSPlatformOneSecond * 2;                              // Start off assuming a two-second delay

        int c = CFArrayGetCount(changedKeys);                                   // Count changes
        CFRange range = { 0, c };
        int c1 = (CFArrayContainsValue(changedKeys, range, NetworkChangedKey_Hostnames   ) != 0);
        int c2 = (CFArrayContainsValue(changedKeys, range, NetworkChangedKey_Computername) != 0);
        int c3 = (CFArrayContainsValue(changedKeys, range, NetworkChangedKey_DynamicDNS  ) != 0);
        int c4 = (CFArrayContainsValue(changedKeys, range, NetworkChangedKey_DNS         ) != 0);
        if (c && c - c1 - c2 - c3 - c4 == 0) delay = mDNSPlatformOneSecond/10;  // If these were the only changes, shorten delay
        
        if (mDNS_LoggingEnabled)
                {
                int i;
                for (i=0; i<c; i++)
                        {
                        char buf[256];
                        if (!CFStringGetCString(CFArrayGetValueAtIndex(changedKeys, i), buf, sizeof(buf), kCFStringEncodingUTF8)) buf[0] = 0;
                        LogInfo("***   NetworkChanged SC key: %s", buf);
                        }
                LogInfo("***   NetworkChanged   *** %d change%s %s%s%s%sdelay %d",
                        c, c>1?"s":"",
                        c1 ? "(Local Hostname) " : "",
                        c2 ? "(Computer Name) "  : "",
                        c3 ? "(DynamicDNS) "     : "",
                        c4 ? "(DNS) "            : "",
                        delay);
                }

        SetNetworkChanged(m, delay);
        
        // KeyChain frequently fails to notify clients of change events. To work around this
        // we set a timer and periodically poll to detect if any changes have occurred.
        // Without this Back To My Mac just does't work for a large number of users.
        // See <rdar://problem/5124399> Not getting Keychain Changed events when enabling BTMM
        if (c3 || CFArrayContainsValue(changedKeys, range, NetworkChangedKey_BackToMyMac))
                {
                LogInfo("***   NetworkChanged   *** starting KeyChainBugTimer");
                m->p->KeyChainBugTimer    = NonZeroTime(m->timenow + delay);
                m->p->KeyChainBugInterval = mDNSPlatformOneSecond;
                }

        mDNS_Unlock(m);

        // If DNS settings changed, immediately force a reconfig (esp. cache flush)
        // Similarly, if an interface changed that is explicitly IPv4 link local, immediately force a reconfig
        if (c4 || ChangedKeysHaveIPv4LL(changedKeys)) mDNSMacOSXNetworkChanged(m);

        KQueueUnlock(m, "NetworkChanged");
        }

mDNSlocal mStatus WatchForNetworkChanges(mDNS *const m)
        {
        mStatus err = -1;
        SCDynamicStoreContext context = { 0, m, NULL, NULL, NULL };
        SCDynamicStoreRef     store    = SCDynamicStoreCreate(NULL, CFSTR("mDNSResponder:WatchForNetworkChanges"), NetworkChanged, &context);
        CFMutableArrayRef     keys     = CFArrayCreateMutable(NULL, 0, &kCFTypeArrayCallBacks);
        CFStringRef           pattern1 = SCDynamicStoreKeyCreateNetworkInterfaceEntity(NULL, kSCDynamicStoreDomainState, kSCCompAnyRegex, kSCEntNetIPv4);
        CFStringRef           pattern2 = SCDynamicStoreKeyCreateNetworkInterfaceEntity(NULL, kSCDynamicStoreDomainState, kSCCompAnyRegex, kSCEntNetIPv6);
        CFMutableArrayRef     patterns = CFArrayCreateMutable(NULL, 0, &kCFTypeArrayCallBacks);

        if (!store) { LogMsg("SCDynamicStoreCreate failed: %s", SCErrorString(SCError())); goto error; }
        if (!keys || !pattern1 || !pattern2 || !patterns) goto error;

        CFArrayAppendValue(keys, NetworkChangedKey_IPv4);
        CFArrayAppendValue(keys, NetworkChangedKey_IPv6);
        CFArrayAppendValue(keys, NetworkChangedKey_Hostnames);
        CFArrayAppendValue(keys, NetworkChangedKey_Computername);
        CFArrayAppendValue(keys, NetworkChangedKey_DNS);
        CFArrayAppendValue(keys, NetworkChangedKey_DynamicDNS);
        CFArrayAppendValue(keys, NetworkChangedKey_BackToMyMac);
        CFArrayAppendValue(keys, NetworkChangedKey_PowerSettings); // should remove as part of <rdar://problem/6751656>
        CFArrayAppendValue(keys, NetworkChangedKey_BTMMConnectivity);
        CFArrayAppendValue(patterns, pattern1);
        CFArrayAppendValue(patterns, pattern2);
        CFArrayAppendValue(patterns, CFSTR("State:/Network/Interface/[^/]+/AirPort"));
        if (!SCDynamicStoreSetNotificationKeys(store, keys, patterns))
                { LogMsg("SCDynamicStoreSetNotificationKeys failed: %s", SCErrorString(SCError())); goto error; }

#ifdef __LIB_DISPATCH__
        if (!SCDynamicStoreSetDispatchQueue(store, dispatch_get_main_queue()))
                { LogMsg("SCDynamicStoreCreateRunLoopSource failed: %s", SCErrorString(SCError())); goto error; }
#else
        m->p->StoreRLS = SCDynamicStoreCreateRunLoopSource(NULL, store, 0);
        if (!m->p->StoreRLS) { LogMsg("SCDynamicStoreCreateRunLoopSource failed: %s", SCErrorString(SCError())); goto error; }
        CFRunLoopAddSource(CFRunLoopGetCurrent(), m->p->StoreRLS, kCFRunLoopDefaultMode);
#endif
        m->p->Store = store;
        err = 0;
        goto exit;

        error:
        if (store)    CFRelease(store);

        exit:
        if (patterns) CFRelease(patterns);
        if (pattern2) CFRelease(pattern2);
        if (pattern1) CFRelease(pattern1);
        if (keys)     CFRelease(keys);

        return(err);
        }

#if 0 // <rdar://problem/6751656>
mDNSlocal void PMChanged(void *context)
        {
        mDNS *const m = (mDNS *const)context;

        KQueueLock(m);
        mDNS_Lock(m);
        
        LogSPS("PMChanged");
        
        SetNetworkChanged(m, mDNSPlatformOneSecond * 2);
        
        mDNS_Unlock(m);
        KQueueUnlock(m, "PMChanged");
        }

mDNSlocal mStatus WatchForPMChanges(mDNS *const m)
        {
        m->p->PMRLS = IOPMPrefsNotificationCreateRunLoopSource(PMChanged, m);
        if (!m->p->PMRLS) { LogMsg("IOPMPrefsNotificationCreateRunLoopSource failed!"); return mStatus_UnknownErr; }

        CFRunLoopAddSource(CFRunLoopGetCurrent(), m->p->PMRLS, kCFRunLoopDefaultMode);

        return mStatus_NoError;
        }
#endif

#ifndef KEV_DL_WAKEFLAGS_CHANGED
#define KEV_DL_WAKEFLAGS_CHANGED 17
#endif

mDNSlocal void SysEventCallBack(int s1, short __unused filter, void *context)
        {
        mDNS *const m = (mDNS *const)context;

        mDNS_Lock(m);

        struct { struct kern_event_msg k; char extra[256]; } msg;
        int bytes = recv(s1, &msg, sizeof(msg), 0);
        if (bytes < 0)
                LogMsg("SysEventCallBack: recv error %d errno %d (%s)", bytes, errno, strerror(errno));
        else
                {
                LogInfo("SysEventCallBack got %d bytes size %d %X %s %X %s %X %s id %d code %d %s",
                        bytes, msg.k.total_size,
                        msg.k.vendor_code , msg.k.vendor_code  == KEV_VENDOR_APPLE  ? "KEV_VENDOR_APPLE"  : "?",
                        msg.k.kev_class   , msg.k.kev_class    == KEV_NETWORK_CLASS ? "KEV_NETWORK_CLASS" : "?",
                        msg.k.kev_subclass, msg.k.kev_subclass == KEV_DL_SUBCLASS   ? "KEV_DL_SUBCLASS"   : "?",
                        msg.k.id, msg.k.event_code,
                        msg.k.event_code == KEV_DL_SIFFLAGS             ? "KEV_DL_SIFFLAGS"             :
                        msg.k.event_code == KEV_DL_SIFMETRICS           ? "KEV_DL_SIFMETRICS"           :
                        msg.k.event_code == KEV_DL_SIFMTU               ? "KEV_DL_SIFMTU"               :
                        msg.k.event_code == KEV_DL_SIFPHYS              ? "KEV_DL_SIFPHYS"              :
                        msg.k.event_code == KEV_DL_SIFMEDIA             ? "KEV_DL_SIFMEDIA"             :
                        msg.k.event_code == KEV_DL_SIFGENERIC           ? "KEV_DL_SIFGENERIC"           :
                        msg.k.event_code == KEV_DL_ADDMULTI             ? "KEV_DL_ADDMULTI"             :
                        msg.k.event_code == KEV_DL_DELMULTI             ? "KEV_DL_DELMULTI"             :
                        msg.k.event_code == KEV_DL_IF_ATTACHED          ? "KEV_DL_IF_ATTACHED"          :
                        msg.k.event_code == KEV_DL_IF_DETACHING         ? "KEV_DL_IF_DETACHING"         :
                        msg.k.event_code == KEV_DL_IF_DETACHED          ? "KEV_DL_IF_DETACHED"          :
                        msg.k.event_code == KEV_DL_LINK_OFF             ? "KEV_DL_LINK_OFF"             :
                        msg.k.event_code == KEV_DL_LINK_ON              ? "KEV_DL_LINK_ON"              :
                        msg.k.event_code == KEV_DL_PROTO_ATTACHED       ? "KEV_DL_PROTO_ATTACHED"       :
                        msg.k.event_code == KEV_DL_PROTO_DETACHED       ? "KEV_DL_PROTO_DETACHED"       :
                        msg.k.event_code == KEV_DL_LINK_ADDRESS_CHANGED ? "KEV_DL_LINK_ADDRESS_CHANGED" :
                        msg.k.event_code == KEV_DL_WAKEFLAGS_CHANGED    ? "KEV_DL_WAKEFLAGS_CHANGED"    : "?");

                if (msg.k.event_code == KEV_DL_WAKEFLAGS_CHANGED) SetNetworkChanged(m, mDNSPlatformOneSecond * 2);
                }

        mDNS_Unlock(m);
        }

mDNSlocal mStatus WatchForSysEvents(mDNS *const m)
        {
        m->p->SysEventNotifier = socket(PF_SYSTEM, SOCK_RAW, SYSPROTO_EVENT);
        if (m->p->SysEventNotifier < 0)
                { LogMsg("WatchForSysEvents: socket failed error %d errno %d (%s)", m->p->SysEventNotifier, errno, strerror(errno)); return(mStatus_NoMemoryErr); }

        struct kev_request kev_req = { KEV_VENDOR_APPLE, KEV_NETWORK_CLASS, KEV_DL_SUBCLASS };
        int err = ioctl(m->p->SysEventNotifier, SIOCSKEVFILT, &kev_req);
        if (err < 0)
                {
                LogMsg("WatchForSysEvents: SIOCSKEVFILT failed error %d errno %d (%s)", err, errno, strerror(errno));
                close(m->p->SysEventNotifier);
                m->p->SysEventNotifier = -1;
                return(mStatus_UnknownErr);
                }

        m->p->SysEventKQueue.KQcallback = SysEventCallBack;
        m->p->SysEventKQueue.KQcontext  = m;
        m->p->SysEventKQueue.KQtask     = "System Event Notifier";
        KQueueSet(m->p->SysEventNotifier, EV_ADD, EVFILT_READ, &m->p->SysEventKQueue);

        return(mStatus_NoError);
        }

#ifndef NO_SECURITYFRAMEWORK
mDNSlocal OSStatus KeychainChanged(SecKeychainEvent keychainEvent, SecKeychainCallbackInfo *info, void *context)
        {
        LogInfo("***   Keychain Changed   ***");
        mDNS *const m = (mDNS *const)context;
        SecKeychainRef skc;
        OSStatus err = SecKeychainCopyDefault(&skc);
        if (!err)
                {
                if (info->keychain == skc)
                        {
                        // For delete events, attempt to verify what item was deleted fail because the item is already gone, so we just assume they may be relevant
                        mDNSBool relevant = (keychainEvent == kSecDeleteEvent);
                        if (!relevant)
                                {
                                UInt32 tags[3] = { kSecTypeItemAttr, kSecServiceItemAttr, kSecAccountItemAttr };
                                SecKeychainAttributeInfo attrInfo = { 3, tags, NULL };  // Count, array of tags, array of formats
                                SecKeychainAttributeList *a = NULL;
                                err = SecKeychainItemCopyAttributesAndData(info->item, &attrInfo, NULL, &a, NULL, NULL);
                                if (!err)
                                        {
                                        relevant = ((a->attr[0].length == 4 && (!strncasecmp(a->attr[0].data, "ddns", 4) || !strncasecmp(a->attr[0].data, "sndd", 4))) ||
                                                                (a->attr[1].length >= 4 && (!strncasecmp(a->attr[1].data, "dns:", 4))));
                                        SecKeychainItemFreeAttributesAndData(a, NULL);
                                        }
                                }
                        if (relevant)
                                {
                                LogInfo("***   Keychain Changed   *** KeychainEvent=%d %s",
                                        keychainEvent,
                                        keychainEvent == kSecAddEvent    ? "kSecAddEvent"    :
                                        keychainEvent == kSecDeleteEvent ? "kSecDeleteEvent" :
                                        keychainEvent == kSecUpdateEvent ? "kSecUpdateEvent" : "<Unknown>");
                                // We're running on the CFRunLoop (Mach port) thread, not the kqueue thread, so we need to grab the KQueueLock before proceeding
                                KQueueLock(m);
                                mDNS_Lock(m);
                                SetDomainSecrets(m);
                                mDNS_Unlock(m);
                                KQueueUnlock(m, "KeychainChanged");
                                }
                        }
                CFRelease(skc);
                }

        return 0;
        }
#endif

mDNSlocal void PowerOn(mDNS *const m)
        {
        mDNSCoreMachineSleep(m, false);         // Will set m->SleepState = SleepState_Awake;
        if (m->p->WakeAtUTC)
                {
                long utc = mDNSPlatformUTC();
                mDNSPowerRequest(-1,-1);                // Need to explicitly clear any previous power requests -- they're not cleared automatically on wake
                if      (m->p->WakeAtUTC - utc > 30) LogInfo("PowerChanged PowerOn %d seconds early, assuming not maintenance wake", m->p->WakeAtUTC - utc);
                else if (utc - m->p->WakeAtUTC > 30) LogInfo("PowerChanged PowerOn %d seconds late, assuming not maintenance wake", utc - m->p->WakeAtUTC);
                else
                        {
                        mDNSs32 i = 20;
                        //int result = mDNSPowerRequest(0, i);
                        //if (result == kIOReturnNotReady) do i += (i<20) ? 1 : ((i+3)/4); while (mDNSPowerRequest(0, i) == kIOReturnNotReady);
                        LogMsg("PowerChanged: Waking for network maintenance operations %d seconds early; re-sleeping in %d seconds", m->p->WakeAtUTC - utc, i);
                        m->p->RequestReSleep = mDNS_TimeNow(m) + i * mDNSPlatformOneSecond;
                        }
                }
        }

mDNSlocal void PowerChanged(void *refcon, io_service_t service, natural_t messageType, void *messageArgument)
        {
        mDNS *const m = (mDNS *const)refcon;
        KQueueLock(m);
        (void)service;    // Parameter not used
        debugf("PowerChanged %X %lX", messageType, messageArgument);

        // Make sure our m->SystemWakeOnLANEnabled value correctly reflects the current system setting
        m->SystemWakeOnLANEnabled = SystemWakeForNetworkAccess();

        switch(messageType)
                {
                case kIOMessageCanSystemPowerOff:               LogInfo("PowerChanged kIOMessageCanSystemPowerOff     (no action)");    break;  // E0000240
                case kIOMessageSystemWillPowerOff:              LogInfo("PowerChanged kIOMessageSystemWillPowerOff");                                                   // E0000250
                                                                                                mDNSCoreMachineSleep(m, true);
                                                                                                if (m->SleepState == SleepState_Sleeping) mDNSMacOSXNetworkChanged(m);
                                                                                                break;
                case kIOMessageSystemWillNotPowerOff:   LogInfo("PowerChanged kIOMessageSystemWillNotPowerOff (no action)");    break;  // E0000260
                case kIOMessageCanSystemSleep:                  LogInfo("PowerChanged kIOMessageCanSystemSleep        (no action)");    break;  // E0000270
                case kIOMessageSystemWillSleep:                 LogInfo("PowerChanged kIOMessageSystemWillSleep");                                                              // E0000280
                                                                                                mDNSCoreMachineSleep(m, true);
                                                                                                break;
                case kIOMessageSystemWillNotSleep:              LogInfo("PowerChanged kIOMessageSystemWillNotSleep    (no action)");    break;  // E0000290
                case kIOMessageSystemHasPoweredOn:              LogInfo("PowerChanged kIOMessageSystemHasPoweredOn");                                                   // E0000300
                                                                                                // If still sleeping (didn't get 'WillPowerOn' message for some reason?) wake now
                                                                                                if (m->SleepState)
                                                                                                        {
                                                                                                        LogMsg("PowerChanged kIOMessageSystemHasPoweredOn: ERROR m->SleepState %d", m->SleepState);
                                                                                                        PowerOn(m);
                                                                                                        }
                                                                                                // Just to be safe, schedule a mDNSMacOSXNetworkChanged(), in case we never received
                                                                                                // the System Configuration Framework "network changed" event that we expect
                                                                                                // to receive some time shortly after the kIOMessageSystemWillPowerOn message
                                                                                                mDNS_Lock(m);
                                                                                                if (!m->p->NetworkChanged ||
                                                                                                        m->p->NetworkChanged - NonZeroTime(m->timenow + mDNSPlatformOneSecond * 2) < 0)
                                                                                                        m->p->NetworkChanged = NonZeroTime(m->timenow + mDNSPlatformOneSecond * 2);
                                                                                                mDNS_Unlock(m);
                                                                                        
                                                                                                break;
                case kIOMessageSystemWillRestart:               LogInfo("PowerChanged kIOMessageSystemWillRestart     (no action)");    break;  // E0000310
                case kIOMessageSystemWillPowerOn:               LogInfo("PowerChanged kIOMessageSystemWillPowerOn");                                                    // E0000320

                                                                                        #if ! TARGET_OS_EMBEDDED
                                                                                                // On Leopard and earlier, on wake from sleep, instead of reporting link state down, Apple
                                                                                                // Ethernet drivers report "hardware incapable of detecting link state", which the kernel
                                                                                                // interprets as "should assume we have networking", which results in the first 4-5 seconds
                                                                                                // of packets vanishing into a black hole. To work around this, on wake from sleep,
                                                                                                // we block for five seconds to let Ethernet come up, and then resume normal operation.
                                                                                                if (OSXVers < OSXVers_10_6_SnowLeopard)
                                                                                                        {
                                                                                                        sleep(5);
                                                                                                        LogMsg("Running on Mac OS X version 10.%d earlier than 10.6; "
                                                                                                                "PowerChanged did sleep(5) to wait for Ethernet hardware", OSXVers - OSXVers_Base);
                                                                                                        }
                                                                                        #endif

                                                                                                // Make sure our interface list is cleared to the empty state, then tell mDNSCore to wake
                                                                                                if (m->SleepState != SleepState_Sleeping)
                                                                                                        {
                                                                                                        LogMsg("kIOMessageSystemWillPowerOn: ERROR m->SleepState %d", m->SleepState);
                                                                                                        m->SleepState = SleepState_Sleeping;
                                                                                                        mDNSMacOSXNetworkChanged(m);
                                                                                                        }
                                                                                                PowerOn(m);
                                                                                                break;
                default:                                                                LogInfo("PowerChanged unknown message %X", messageType);                                break;
                }

        if (messageType == kIOMessageSystemWillSleep) m->p->SleepCookie = (long)messageArgument;
        else IOAllowPowerChange(m->p->PowerConnection, (long)messageArgument);

        KQueueUnlock(m, "PowerChanged Sleep/Wake");
        }

// iPhone OS doesn't currently have SnowLeopard's IO Power Management
// but it does define kIOPMAcknowledgmentOptionSystemCapabilityRequirements
#if defined(kIOPMAcknowledgmentOptionSystemCapabilityRequirements) && !TARGET_OS_EMBEDDED
mDNSlocal void SnowLeopardPowerChanged(void *refcon, IOPMConnection connection, IOPMConnectionMessageToken token, IOPMSystemPowerStateCapabilities eventDescriptor)
        {
        mDNS *const m = (mDNS *const)refcon;
        KQueueLock(m);
        LogSPS("SnowLeopardPowerChanged %X %X %X%s%s%s%s%s",
                connection, token, eventDescriptor,
                eventDescriptor & kIOPMSystemPowerStateCapabilityCPU     ? " CPU"     : "",
                eventDescriptor & kIOPMSystemPowerStateCapabilityVideo   ? " Video"   : "",
                eventDescriptor & kIOPMSystemPowerStateCapabilityAudio   ? " Audio"   : "",
                eventDescriptor & kIOPMSystemPowerStateCapabilityNetwork ? " Network" : "",
                eventDescriptor & kIOPMSystemPowerStateCapabilityDisk    ? " Disk"    : "");

        // Make sure our m->SystemWakeOnLANEnabled value correctly reflects the current system setting
        m->SystemWakeOnLANEnabled = SystemWakeForNetworkAccess();

        if (eventDescriptor & kIOPMSystemPowerStateCapabilityCPU)
                {
                // We might be in Sleeping or Transferring state. When we go from "wakeup" to "sleep" state, we don't
                // go directly to sleep state, but transfer in to the sleep state during which SleepState is set to
                // SleepState_Transferring. During that time, we might get another wakeup before we transition to Sleeping
                // state. In that case, we need to acknowledge the previous "sleep" before we acknowledge the wakeup.
                if (m->SleepLimit)
                        {
                        LogSPS("SnowLeopardPowerChanged: Waking up, Acking old Sleep, SleepLimit %d SleepState %d", m->SleepLimit, m->SleepState);
                        IOPMConnectionAcknowledgeEvent(connection, m->p->SleepCookie);
                        m->SleepLimit = 0;
                        }
                LogSPS("SnowLeopardPowerChanged: Waking up, Acking Wakeup, SleepLimit %d SleepState %d", m->SleepLimit, m->SleepState);
                // CPU Waking. Note: Can get this message repeatedly, as other subsystems power up or down.
                if (m->SleepState != SleepState_Awake) PowerOn(m);
                IOPMConnectionAcknowledgeEvent(connection, token);
                }
        else
                {
                // CPU sleeping. Should not get this repeatedly -- once we're told that the CPU is halting
                // we should hear nothing more until we're told that the CPU has started executing again.
                if (m->SleepState) LogMsg("SnowLeopardPowerChanged: Sleep Error %X m->SleepState %d", eventDescriptor, m->SleepState);
                //sleep(5);
                //mDNSMacOSXNetworkChanged(m);
                mDNSCoreMachineSleep(m, true);
                //if (m->SleepState == SleepState_Sleeping) mDNSMacOSXNetworkChanged(m);
                m->p->SleepCookie = token;
                }

        KQueueUnlock(m, "SnowLeopardPowerChanged Sleep/Wake");
        }
#endif

#if COMPILER_LIKES_PRAGMA_MARK
#pragma mark -
#pragma mark - Initialization & Teardown
#endif

CF_EXPORT CFDictionaryRef _CFCopySystemVersionDictionary(void);
CF_EXPORT const CFStringRef _kCFSystemVersionProductNameKey;
CF_EXPORT const CFStringRef _kCFSystemVersionProductVersionKey;
CF_EXPORT const CFStringRef _kCFSystemVersionBuildVersionKey;

// Major version  6 is 10.2.x (Jaguar)
// Major version  7 is 10.3.x (Panther)
// Major version  8 is 10.4.x (Tiger)
// Major version  9 is 10.5.x (Leopard)
// Major version 10 is 10.6.x (SnowLeopard)
mDNSexport int mDNSMacOSXSystemBuildNumber(char *HINFO_SWstring)
        {
        int major = 0, minor = 0;
        char letter = 0, prodname[256]="<Unknown>", prodvers[256]="<Unknown>", buildver[256]="<Unknown>";
        CFDictionaryRef vers = _CFCopySystemVersionDictionary();
        if (vers)
                {
                CFStringRef cfprodname = CFDictionaryGetValue(vers, _kCFSystemVersionProductNameKey);
                CFStringRef cfprodvers = CFDictionaryGetValue(vers, _kCFSystemVersionProductVersionKey);
                CFStringRef cfbuildver = CFDictionaryGetValue(vers, _kCFSystemVersionBuildVersionKey);
                if (cfprodname) CFStringGetCString(cfprodname, prodname, sizeof(prodname), kCFStringEncodingUTF8);
                if (cfprodvers) CFStringGetCString(cfprodvers, prodvers, sizeof(prodvers), kCFStringEncodingUTF8);
                if (cfbuildver && CFStringGetCString(cfbuildver, buildver, sizeof(buildver), kCFStringEncodingUTF8))
                        sscanf(buildver, "%d%c%d", &major, &letter, &minor);
                CFRelease(vers);
                }
        if (!major) { major=8; LogMsg("Note: No Major Build Version number found; assuming 8"); }
        if (HINFO_SWstring) mDNS_snprintf(HINFO_SWstring, 256, "%s %s (%s), %s", prodname, prodvers, buildver, STRINGIFY(mDNSResponderVersion));
        return(major);
        }

// Test to see if we're the first client running on UDP port 5353, by trying to bind to 5353 without using SO_REUSEPORT.
// If we fail, someone else got here first. That's not a big problem; we can share the port for multicast responses --
// we just need to be aware that we shouldn't expect to successfully receive unicast UDP responses.
mDNSlocal mDNSBool mDNSPlatformInit_CanReceiveUnicast(void)
        {
        int err = -1;
        int s = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
        if (s < 3)
                LogMsg("mDNSPlatformInit_CanReceiveUnicast: socket error %d errno %d (%s)", s, errno, strerror(errno));
        else
                {
                struct sockaddr_in s5353;
                s5353.sin_family      = AF_INET;
                s5353.sin_port        = MulticastDNSPort.NotAnInteger;
                s5353.sin_addr.s_addr = 0;
                err = bind(s, (struct sockaddr *)&s5353, sizeof(s5353));
                close(s);
                }

        if (err) LogMsg("No unicast UDP responses");
        else     debugf("Unicast UDP responses okay");
        return(err == 0);
        }

// Construction of Default Browse domain list (i.e. when clients pass NULL) is as follows:
// 1) query for b._dns-sd._udp.local on LocalOnly interface
//    (.local manually generated via explicit callback)
// 2) for each search domain (from prefs pane), query for b._dns-sd._udp.<searchdomain>.
// 3) for each result from (2), register LocalOnly PTR record b._dns-sd._udp.local. -> <result>
// 4) result above should generate a callback from question in (1).  result added to global list
// 5) global list delivered to client via GetSearchDomainList()
// 6) client calls to enumerate domains now go over LocalOnly interface
//    (!!!KRS may add outgoing interface in addition)

mDNSlocal mStatus mDNSPlatformInit_setup(mDNS *const m)
        {
        mStatus err;
        m->p->CFRunLoop = CFRunLoopGetCurrent();

        char HINFO_SWstring[256] = "";
        OSXVers = mDNSMacOSXSystemBuildNumber(HINFO_SWstring);

        // In 10.4, mDNSResponder is launched very early in the boot process, while other subsystems are still in the process of starting up.
        // If we can't read the user's preferences, then we sleep a bit and try again, for up to five seconds before we give up.
        int i;
        for (i=0; i<100; i++)
                {
                domainlabel testlabel;
                testlabel.c[0] = 0;
                GetUserSpecifiedLocalHostName(&testlabel);
                if (testlabel.c[0]) break;
                usleep(50000);
                }

        m->hostlabel.c[0]        = 0;

        int    get_model[2] = { CTL_HW, HW_MODEL };
        size_t len_model = sizeof(HINFO_HWstring_buffer);
        
        // Normal Apple model names are of the form "iPhone2,1", and
        // internal code names are strings containing no commas, e.g. "N88AP".
        // We used to ignore internal code names, but Apple now uses these internal code names
        // even in released shipping products, so we no longer ignore strings containing no commas.
//      if (sysctl(get_model, 2, HINFO_HWstring_buffer, &len_model, NULL, 0) == 0 && strchr(HINFO_HWstring_buffer, ','))
        if (sysctl(get_model, 2, HINFO_HWstring_buffer, &len_model, NULL, 0) == 0)
                HINFO_HWstring = HINFO_HWstring_buffer;
        HINFO_HWstring_prefixlen = strcspn(HINFO_HWstring, "0123456789");

        if (OSXVers <  OSXVers_10_3_Panther     ) m->KnownBugs |= mDNS_KnownBug_PhantomInterfaces;
        if (OSXVers <= OSXVers_10_6_SnowLeopard ) m->KnownBugs |= mDNS_KnownBug_LimitedIPv6;
        if (OSXVers >= OSXVers_10_6_SnowLeopard ) m->KnownBugs |= mDNS_KnownBug_LossySyslog;
        if (mDNSPlatformInit_CanReceiveUnicast()) m->CanReceiveUnicastOn5353 = mDNStrue;

        mDNSu32 hlen = mDNSPlatformStrLen(HINFO_HWstring);
        mDNSu32 slen = mDNSPlatformStrLen(HINFO_SWstring);
        if (hlen + slen < 254)
                {
                m->HIHardware.c[0] = hlen;
                m->HISoftware.c[0] = slen;
                mDNSPlatformMemCopy(&m->HIHardware.c[1], HINFO_HWstring, hlen);
                mDNSPlatformMemCopy(&m->HISoftware.c[1], HINFO_SWstring, slen);
                }

        m->p->permanentsockets.port  = MulticastDNSPort;
        m->p->permanentsockets.m     = m;
        m->p->permanentsockets.sktv4 = -1;
        m->p->permanentsockets.kqsv4.KQcallback = myKQSocketCallBack;
        m->p->permanentsockets.kqsv4.KQcontext  = &m->p->permanentsockets;
        m->p->permanentsockets.kqsv4.KQtask     = "UDP packet reception";
#ifndef NO_IPV6
        m->p->permanentsockets.sktv6 = -1;
        m->p->permanentsockets.kqsv6.KQcallback = myKQSocketCallBack;
        m->p->permanentsockets.kqsv6.KQcontext  = &m->p->permanentsockets;
        m->p->permanentsockets.kqsv6.KQtask     = "UDP packet reception";
#endif

        err = SetupSocket(&m->p->permanentsockets, MulticastDNSPort, AF_INET, mDNSNULL);
#ifndef NO_IPV6
        err = SetupSocket(&m->p->permanentsockets, MulticastDNSPort, AF_INET6, mDNSNULL);
#endif

        struct sockaddr_in s4;
        socklen_t n4 = sizeof(s4);
        if (getsockname(m->p->permanentsockets.sktv4, (struct sockaddr *)&s4, &n4) < 0) LogMsg("getsockname v4 error %d (%s)", errno, strerror(errno));
        else m->UnicastPort4.NotAnInteger = s4.sin_port;
#ifndef NO_IPV6
        if (m->p->permanentsockets.sktv6 >= 0)
                {
                struct sockaddr_in6 s6;
                socklen_t n6 = sizeof(s6);
                if (getsockname(m->p->permanentsockets.sktv6, (struct sockaddr *)&s6, &n6) < 0) LogMsg("getsockname v6 error %d (%s)", errno, strerror(errno));
                else m->UnicastPort6.NotAnInteger = s6.sin6_port;
                }
#endif

        m->p->InterfaceList      = mDNSNULL;
        m->p->userhostlabel.c[0] = 0;
        m->p->usernicelabel.c[0] = 0;
        m->p->prevoldnicelabel.c[0] = 0;
        m->p->prevnewnicelabel.c[0] = 0;
        m->p->prevoldhostlabel.c[0] = 0;
        m->p->prevnewhostlabel.c[0] = 0;
        m->p->NotifyUser         = 0;
        m->p->KeyChainBugTimer   = 0;
        m->p->WakeAtUTC          = 0;
        m->p->RequestReSleep     = 0;
        
#if APPLE_OSX_mDNSResponder
        uuid_generate(m->asl_uuid);
#endif

        m->AutoTunnelHostAddr.b[0] = 0;         // Zero out AutoTunnelHostAddr so UpdateInterfaceList() know it has to set it up
        m->AutoTunnelRelayAddr = zerov6Addr;

        NetworkChangedKey_IPv4         = SCDynamicStoreKeyCreateNetworkGlobalEntity(NULL, kSCDynamicStoreDomainState, kSCEntNetIPv4);
        NetworkChangedKey_IPv6         = SCDynamicStoreKeyCreateNetworkGlobalEntity(NULL, kSCDynamicStoreDomainState, kSCEntNetIPv6);
        NetworkChangedKey_Hostnames    = SCDynamicStoreKeyCreateHostNames(NULL);
        NetworkChangedKey_Computername = SCDynamicStoreKeyCreateComputerName(NULL);
        NetworkChangedKey_DNS          = SCDynamicStoreKeyCreateNetworkGlobalEntity(NULL, kSCDynamicStoreDomainState, kSCEntNetDNS);
        if (!NetworkChangedKey_IPv4 || !NetworkChangedKey_IPv6 || !NetworkChangedKey_Hostnames || !NetworkChangedKey_Computername || !NetworkChangedKey_DNS)
                { LogMsg("SCDynamicStore string setup failed"); return(mStatus_NoMemoryErr); }

        err = WatchForNetworkChanges(m);
        if (err) { LogMsg("mDNSPlatformInit_setup: WatchForNetworkChanges failed %d", err); return(err); }

#if 0 // <rdar://problem/6751656>
        err = WatchForPMChanges(m);
        if (err) { LogMsg("mDNSPlatformInit_setup: WatchForPMChanges failed %d", err); return(err); }
#endif

        err = WatchForSysEvents(m);
        if (err) { LogMsg("mDNSPlatformInit_setup: WatchForSysEvents failed %d", err); return(err); }

        mDNSs32 utc = mDNSPlatformUTC();
        m->SystemWakeOnLANEnabled = SystemWakeForNetworkAccess();
        UpdateInterfaceList(m, utc);
        SetupActiveInterfaces(m, utc);

        // Explicitly ensure that our Keychain operations utilize the system domain.
#ifndef NO_SECURITYFRAMEWORK
        SecKeychainSetPreferenceDomain(kSecPreferencesDomainSystem);
#endif

        mDNS_Lock(m);
        SetDomainSecrets(m);
        SetLocalDomains();
        mDNS_Unlock(m);

#ifndef NO_SECURITYFRAMEWORK
        err = SecKeychainAddCallback(KeychainChanged, kSecAddEventMask|kSecDeleteEventMask|kSecUpdateEventMask, m);
        if (err) { LogMsg("mDNSPlatformInit_setup: SecKeychainAddCallback failed %d", err); return(err); }
#endif

#if !defined(kIOPMAcknowledgmentOptionSystemCapabilityRequirements) || TARGET_OS_EMBEDDED
        LogMsg("Note: Compiled without SnowLeopard Fine-Grained Power Management support");
#else
        IOPMConnection c;
        IOReturn iopmerr = IOPMConnectionCreate(CFSTR("mDNSResponder"), kIOPMSystemPowerStateCapabilityCPU, &c);
        if (iopmerr) LogMsg("IOPMConnectionCreate failed %d", iopmerr);
        else
                {
                iopmerr = IOPMConnectionSetNotification(c, m, SnowLeopardPowerChanged);
                if (iopmerr) LogMsg("IOPMConnectionSetNotification failed %d", iopmerr);
                else
                        {
                        iopmerr = IOPMConnectionScheduleWithRunLoop(c, CFRunLoopGetCurrent(), kCFRunLoopDefaultMode);
                        if (iopmerr) LogMsg("IOPMConnectionScheduleWithRunLoop failed %d", iopmerr);
                        }
                }
        m->p->IOPMConnection = iopmerr ? mDNSNULL : c;
        if (iopmerr) // If IOPMConnectionCreate unavailable or failed, proceed with old-style power notification code below
#endif // kIOPMAcknowledgmentOptionSystemCapabilityRequirements
                {
                m->p->PowerConnection = IORegisterForSystemPower(m, &m->p->PowerPortRef, PowerChanged, &m->p->PowerNotifier);
                if (!m->p->PowerConnection) { LogMsg("mDNSPlatformInit_setup: IORegisterForSystemPower failed"); return(-1); }
                else
                        {
#ifdef __LIB_DISPATCH__
                        IONotificationPortSetDispatchQueue(m->p->PowerPortRef, dispatch_get_main_queue());
#else
                        CFRunLoopAddSource(CFRunLoopGetCurrent(), IONotificationPortGetRunLoopSource(m->p->PowerPortRef), kCFRunLoopDefaultMode);
#endif /* __LIB_DISPATCH__ */
                        }
                }

#if APPLE_OSX_mDNSResponder
        // Note: We use SPMetricPortability > 35 to indicate a laptop of some kind
        // SPMetricPortability <= 35 means nominally a non-portable machine (i.e. Mac mini or better)
        // Apple TVs, AirPort base stations, and Time Capsules do not actually weigh 3kg, but we assign them
        // higher 'nominal' masses to indicate they should be treated as being relatively less portable than a laptop
        if      (!strncasecmp(HINFO_HWstring, "Xserve",       6)) { SPMetricPortability = 25 /* 30kg */; SPMetricMarginalPower = 84 /* 250W */; SPMetricTotalPower = 85 /* 300W */; }
        else if (!strncasecmp(HINFO_HWstring, "RackMac",      7)) { SPMetricPortability = 25 /* 30kg */; SPMetricMarginalPower = 84 /* 250W */; SPMetricTotalPower = 85 /* 300W */; }
        else if (!strncasecmp(HINFO_HWstring, "MacPro",       6)) { SPMetricPortability = 27 /* 20kg */; SPMetricMarginalPower = 84 /* 250W */; SPMetricTotalPower = 85 /* 300W */; }
        else if (!strncasecmp(HINFO_HWstring, "PowerMac",     8)) { SPMetricPortability = 27 /* 20kg */; SPMetricMarginalPower = 82 /* 160W */; SPMetricTotalPower = 83 /* 200W */; }
        else if (!strncasecmp(HINFO_HWstring, "iMac",         4)) { SPMetricPortability = 30 /* 10kg */; SPMetricMarginalPower = 77 /*  50W */; SPMetricTotalPower = 78 /*  60W */; }
        else if (!strncasecmp(HINFO_HWstring, "Macmini",      7)) { SPMetricPortability = 33 /*  5kg */; SPMetricMarginalPower = 73 /*  20W */; SPMetricTotalPower = 74 /*  25W */; }
        else if (!strncasecmp(HINFO_HWstring, "TimeCapsule", 11)) { SPMetricPortability = 34 /*  4kg */; SPMetricMarginalPower = 10 /*  ~0W */; SPMetricTotalPower = 70 /*  13W */; }
        else if (!strncasecmp(HINFO_HWstring, "AirPort",      7)) { SPMetricPortability = 35 /*  3kg */; SPMetricMarginalPower = 10 /*  ~0W */; SPMetricTotalPower = 70 /*  12W */; }
        else if (!strncasecmp(HINFO_HWstring, "AppleTV",      7)) { SPMetricPortability = 35 /*  3kg */; SPMetricMarginalPower = 10 /*  ~0W */; SPMetricTotalPower = 73 /*  20W */; }
        else if (!strncasecmp(HINFO_HWstring, "MacBook",      7)) { SPMetricPortability = 37 /*  2kg */; SPMetricMarginalPower = 71 /*  13W */; SPMetricTotalPower = 72 /*  15W */; }
        else if (!strncasecmp(HINFO_HWstring, "PowerBook",    9)) { SPMetricPortability = 37 /*  2kg */; SPMetricMarginalPower = 71 /*  13W */; SPMetricTotalPower = 72 /*  15W */; }
        LogSPS("HW_MODEL: %.*s (%s) Portability %d Marginal Power %d Total Power %d",
                HINFO_HWstring_prefixlen, HINFO_HWstring, HINFO_HWstring, SPMetricPortability, SPMetricMarginalPower, SPMetricTotalPower);

        err = WatchForInternetSharingChanges(m);
        if (err) { LogMsg("WatchForInternetSharingChanges failed %d", err); return(err); }

        m->p->ConndBTMMDict = mDNSNULL;
#endif // APPLE_OSX_mDNSResponder

#ifdef __LIB_DISPATCH__
        // Currently this is not defined. SSL code will eventually fix this. If it becomes
        // critical, we will define this to workaround the bug in SSL.
#ifdef __SSL_NEEDS_SERIALIZATION__
        SSLqueue = dispatch_queue_create("com.apple.mDNSResponder.SSLQueue", NULL);
#else
        SSLqueue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0);
#endif
        if (SSLqueue == mDNSNULL) LogMsg("dispatch_queue_create: SSL queue NULL");
#endif
        return(mStatus_NoError);
        }

mDNSexport mStatus mDNSPlatformInit(mDNS *const m)
        {
#if MDNS_NO_DNSINFO
        LogMsg("Note: Compiled without Apple-specific Split-DNS support");
#endif

        // Adding interfaces will use this flag, so set it now.
        m->DivertMulticastAdvertisements = !m->AdvertiseLocalAddresses;
        
#if APPLE_OSX_mDNSResponder
        m->SPSBrowseCallback = UpdateSPSStatus;
#endif // APPLE_OSX_mDNSResponder

        mStatus result = mDNSPlatformInit_setup(m);

        // We don't do asynchronous initialization on OS X, so by the time we get here the setup will already
        // have succeeded or failed -- so if it succeeded, we should just call mDNSCoreInitComplete() immediately
        if (result == mStatus_NoError)
                {
                mDNSCoreInitComplete(m, mStatus_NoError);

#if ! NO_D2D
                // We only initialize if mDNSCore successfully initialized.
                CHECK_D2D_FUNCTION(D2DInitialize)
                        {
                        D2DStatus ds = D2DInitialize(m->p->CFRunLoop, xD2DServiceCallback, m) ;
                        if (ds != kD2DSuccess)
                                LogMsg("D2DInitialiize failed: %d", ds);
                        else
                                LogMsg("D2DInitialize succeeded");
                        }
#endif // ! NO_D2D
                        
                }
        return(result);
        }

mDNSexport void mDNSPlatformClose(mDNS *const m)
        {
        if (m->p->PowerConnection)
                {
#ifdef __LIB_DISPATCH__
                IONotificationPortSetDispatchQueue(m->p->PowerPortRef, NULL);           
#else
                CFRunLoopRemoveSource(CFRunLoopGetCurrent(), IONotificationPortGetRunLoopSource(m->p->PowerPortRef), kCFRunLoopDefaultMode);
#endif
                // According to <http://developer.apple.com/qa/qa2004/qa1340.html>, a single call
                // to IORegisterForSystemPower creates *three* objects that need to be disposed individually:
                IODeregisterForSystemPower(&m->p->PowerNotifier);
                IOServiceClose            ( m->p->PowerConnection);
                IONotificationPortDestroy ( m->p->PowerPortRef);
                m->p->PowerConnection = 0;
                }

        if (m->p->Store)
                {
#ifdef __LIB_DISPATCH__
                if (!SCDynamicStoreSetDispatchQueue(m->p->Store, NULL))
                        LogMsg("mDNSPlatformClose: SCDynamicStoreSetDispatchQueue failed");
#else
                CFRunLoopRemoveSource(CFRunLoopGetCurrent(), m->p->StoreRLS, kCFRunLoopDefaultMode);
                CFRunLoopSourceInvalidate(m->p->StoreRLS);
                CFRelease(m->p->StoreRLS);
                m->p->StoreRLS = NULL;
#endif
                CFRelease(m->p->Store);
                m->p->Store    = NULL;
                }
        
        if (m->p->PMRLS)
                {
                CFRunLoopRemoveSource(CFRunLoopGetCurrent(), m->p->PMRLS, kCFRunLoopDefaultMode);
                CFRunLoopSourceInvalidate(m->p->PMRLS);
                CFRelease(m->p->PMRLS);
                m->p->PMRLS = NULL;
                }

        if (m->p->SysEventNotifier >= 0) { close(m->p->SysEventNotifier); m->p->SysEventNotifier = -1; }

#if ! NO_D2D
                CHECK_D2D_FUNCTION(D2DTerminate)
                {
                D2DStatus ds = D2DTerminate();
                if (ds != kD2DSuccess)
                        LogMsg("D2DTerminate failed: %d", ds);
                else
                        LogMsg("D2DTerminate succeeded");
                }
#endif // ! NO_D2D

        mDNSs32 utc = mDNSPlatformUTC();
        MarkAllInterfacesInactive(m, utc);
        ClearInactiveInterfaces(m, utc);
        CloseSocketSet(&m->p->permanentsockets);

#if APPLE_OSX_mDNSResponder
        // clean up tunnels
        while (m->TunnelClients)
                {
                ClientTunnel *cur = m->TunnelClients;
                LogInfo("mDNSPlatformClose: removing client tunnel %p %##s from list", cur, cur->dstname.c);
                if (cur->q.ThisQInterval >= 0) mDNS_StopQuery(m, &cur->q);
                AutoTunnelSetKeys(cur, mDNSfalse);
                m->TunnelClients = cur->next;
                freeL("ClientTunnel", cur);
                }

        if (AnonymousRacoonConfig)
                {
                AnonymousRacoonConfig = mDNSNULL;
                LogInfo("mDNSPlatformClose: Deconfiguring autotunnel");
                (void)mDNSConfigureServer(kmDNSDown, mDNSNULL);
                }

        if (m->AutoTunnelHostAddrActive && m->AutoTunnelHostAddr.b[0])
                {
                m->AutoTunnelHostAddrActive = mDNSfalse;
                LogInfo("mDNSPlatformClose: Removing AutoTunnel address %.16a", &m->AutoTunnelHostAddr);
                (void)mDNSAutoTunnelInterfaceUpDown(kmDNSDown, m->AutoTunnelHostAddr.b);
                }
        if (m->p->ConndBTMMDict) CFRelease(m->p->ConndBTMMDict);
#endif // APPLE_OSX_mDNSResponder
        }

#if COMPILER_LIKES_PRAGMA_MARK
#pragma mark -
#pragma mark - General Platform Support Layer functions
#endif

mDNSexport mDNSu32 mDNSPlatformRandomNumber(void)
        {
        return(arc4random());
        }

mDNSexport mDNSs32 mDNSPlatformOneSecond = 1000;
mDNSexport mDNSu32 mDNSPlatformClockDivisor = 0;

mDNSexport mStatus mDNSPlatformTimeInit(void)
        {
        // Notes: Typical values for mach_timebase_info:
        // tbi.numer = 1000 million
        // tbi.denom =   33 million
        // These are set such that (mach_absolute_time() * numer/denom) gives us nanoseconds;
        //          numer  / denom = nanoseconds per hardware clock tick (e.g. 30);
        //          denom  / numer = hardware clock ticks per nanosecond (e.g. 0.033)
        // (denom*1000000) / numer = hardware clock ticks per millisecond (e.g. 33333)
        // So: mach_absolute_time() / ((denom*1000000)/numer) = milliseconds
        //
        // Arithmetic notes:
        // tbi.denom is at least 1, and not more than 2^32-1.
        // Therefore (tbi.denom * 1000000) is at least one million, but cannot overflow a uint64_t.
        // tbi.denom is at least 1, and not more than 2^32-1.
        // Therefore clockdivisor should end up being a number roughly in the range 10^3 - 10^9.
        // If clockdivisor is less than 10^3 then that means that the native clock frequency is less than 1MHz,
        // which is unlikely on any current or future Macintosh.
        // If clockdivisor is greater than 10^9 then that means the native clock frequency is greater than 1000GHz.
        // When we ship Macs with clock frequencies above 1000GHz, we may have to update this code.
        struct mach_timebase_info tbi;
        kern_return_t result = mach_timebase_info(&tbi);
        if (result == KERN_SUCCESS) mDNSPlatformClockDivisor = ((uint64_t)tbi.denom * 1000000) / tbi.numer;
        return(result);
        }

mDNSexport mDNSs32 mDNSPlatformRawTime(void)
        {
        if (mDNSPlatformClockDivisor == 0) { LogMsg("mDNSPlatformRawTime called before mDNSPlatformTimeInit"); return(0); }

        static uint64_t last_mach_absolute_time = 0;
        //static uint64_t last_mach_absolute_time = 0x8000000000000000LL;       // Use this value for testing the alert display
        uint64_t this_mach_absolute_time = mach_absolute_time();
        if ((int64_t)this_mach_absolute_time - (int64_t)last_mach_absolute_time < 0)
                {
                LogMsg("mDNSPlatformRawTime: last_mach_absolute_time %08X%08X", last_mach_absolute_time);
                LogMsg("mDNSPlatformRawTime: this_mach_absolute_time %08X%08X", this_mach_absolute_time);
                // Update last_mach_absolute_time *before* calling NotifyOfElusiveBug()
                last_mach_absolute_time = this_mach_absolute_time;
                // Only show "mach_absolute_time went backwards" notice on 10.4 (build 8xyyy) or later.
                // (This bug happens all the time on 10.3, and we know that's not going to be fixed.)
                if (OSXVers >= OSXVers_10_4_Tiger)
                        NotifyOfElusiveBug("mach_absolute_time went backwards!",
                                "This error occurs from time to time, often on newly released hardware, "
                                "and usually the exact cause is different in each instance.\r\r"
                                "Please file a new Radar bug report with the title “mach_absolute_time went backwards” "
                                "and assign it to Radar Component “Kernel” Version “X”.");
                }
        last_mach_absolute_time = this_mach_absolute_time;

        return((mDNSs32)(this_mach_absolute_time / mDNSPlatformClockDivisor));
        }

mDNSexport mDNSs32 mDNSPlatformUTC(void)
        {
        return time(NULL);
        }

// Locking is a no-op here, because we're single-threaded with a CFRunLoop, so we can never interrupt ourselves
mDNSexport void     mDNSPlatformLock   (const mDNS *const m) { (void)m; }
mDNSexport void     mDNSPlatformUnlock (const mDNS *const m) { (void)m; }
mDNSexport void     mDNSPlatformStrCopy(      void *dst, const void *src)              { strcpy((char *)dst, (char *)src); }
mDNSexport mDNSu32  mDNSPlatformStrLen (                 const void *src)              { return(strlen((char*)src)); }
mDNSexport void     mDNSPlatformMemCopy(      void *dst, const void *src, mDNSu32 len) { memcpy(dst, src, len); }
mDNSexport mDNSBool mDNSPlatformMemSame(const void *dst, const void *src, mDNSu32 len) { return(memcmp(dst, src, len) == 0); }
mDNSexport void     mDNSPlatformMemZero(      void *dst,                  mDNSu32 len) { memset(dst, 0, len); }
#if !(APPLE_OSX_mDNSResponder && MACOSX_MDNS_MALLOC_DEBUGGING)
mDNSexport void *   mDNSPlatformMemAllocate(mDNSu32 len) { return(mallocL("mDNSPlatformMemAllocate", len)); }
#endif
mDNSexport void     mDNSPlatformMemFree    (void *mem)   { freeL("mDNSPlatformMemFree", mem); }

mDNSexport void mDNSPlatformSetAllowSleep(mDNS *const m, mDNSBool allowSleep)
        {
        if (allowSleep && m->p->IOPMAssertion)
                {
                LogInfo("%s Destroying NoIdleSleep power assertion", __FUNCTION__);
                IOPMAssertionRelease(m->p->IOPMAssertion);
                m->p->IOPMAssertion = 0;
                }
        else if (!allowSleep && m->p->IOPMAssertion == 0)
                {
                IOPMAssertionCreateWithName(kIOPMAssertionTypeNoIdleSleep, kIOPMAssertionLevelOn, CFSTR("mDNSResponder"), &m->p->IOPMAssertion);
                LogInfo("%s Creating NoIdleSleep power assertion", __FUNCTION__);
                }
        }