mDNSCore/DNSCommon.h

   1 /*
   2  * Copyright (c) 2002-2003 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. Please obtain a copy of the License at
  10  * http://www.opensource.apple.com/apsl/ and read it before using this
  11  * file.
  12  *
  13  * The Original Code and all software distributed under the License are
  14  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  15  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  16  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  18  * Please see the License for the specific language governing rights and
  19  * limitations under the License.
  20  *
  21  * @APPLE_LICENSE_HEADER_END@
  22
  23     Change History (most recent first):
  24
  25 $Log: DNSCommon.h,v $
  26 Revision 1.30  2005/01/19 03:12:44  cheshire
  27 Move LocalRecordReady() macro from mDNS.c to DNSCommon.h
  28
  29 Revision 1.29  2004/12/15 02:11:22  ksekar
  30 <rdar://problem/3917317> Don't check for Dynamic DNS hostname uniqueness
  31
  32 Revision 1.28  2004/12/06 21:15:22  ksekar
  33 <rdar://problem/3884386> mDNSResponder crashed in CheckServiceRegistrations
  34
  35 Revision 1.27  2004/12/03 07:20:50  ksekar
  36 <rdar://problem/3674208> Wide-Area: Registration of large TXT record fails
  37
  38 Revision 1.26  2004/12/03 05:18:33  ksekar
  39 <rdar://problem/3810596> mDNSResponder needs to return more specific TSIG errors
  40
  41 Revision 1.25  2004/10/26 03:52:02  cheshire
  42 Update checkin comments
  43
  44 Revision 1.24  2004/10/23 01:16:00  cheshire
  45 <rdar://problem/3851677> uDNS operations not always reliable on multi-homed hosts
  46
  47 Revision 1.23  2004/10/03 23:18:58  cheshire
  48 Move address comparison macros from DNSCommon.h to mDNSEmbeddedAPI.h
  49
  50 Revision 1.22  2004/09/30 00:24:56  ksekar
  51 <rdar://problem/3695802> Dynamically update default registration domains on config change
  52
  53 Revision 1.21  2004/09/17 01:08:48  cheshire
  54 Renamed mDNSClientAPI.h to mDNSEmbeddedAPI.h
  55   The name "mDNSClientAPI.h" is misleading to new developers looking at this code. The interfaces
  56   declared in that file are ONLY appropriate to single-address-space embedded applications.
  57   For clients on general-purpose computers, the interfaces defined in dns_sd.h should be used.
  58
  59 Revision 1.20  2004/09/17 00:49:51  cheshire
  60 Get rid of now-unused GetResourceRecord -- the correct (safe) routine to use
  61 is GetLargeResourceRecord
  62
  63 Revision 1.19  2004/09/16 21:59:15  cheshire
  64 For consistency with zerov6Addr, rename zeroIPAddr to zerov4Addr
  65
  66 Revision 1.18  2004/09/16 02:29:39  cheshire
  67 Moved mDNS_Lock/mDNS_Unlock to DNSCommon.c; Added necessary locking around
  68 uDNS_ReceiveMsg, uDNS_StartQuery, uDNS_UpdateRecord, uDNS_RegisterService
  69
  70 Revision 1.17  2004/09/14 23:27:46  cheshire
  71 Fix compile errors
  72
  73 Revision 1.16  2004/08/13 23:46:58  cheshire
  74 "asyncronous" -> "asynchronous"
  75
  76 Revision 1.15  2004/08/10 23:19:14  ksekar
  77 <rdar://problem/3722542>: DNS Extension daemon for Wide Area Rendezvous
  78 Moved routines/constants to allow extern access for garbage collection daemon
  79
  80 Revision 1.14  2004/05/28 23:42:36  ksekar
  81 <rdar://problem/3258021>: Feature: DNS server->client notification on record changes (#7805)
  82
  83 Revision 1.13  2004/05/18 23:51:25  cheshire
  84 Tidy up all checkin comments to use consistent "<rdar://problem/xxxxxxx>" format for bug numbers
  85
  86 Revision 1.12  2004/04/22 04:03:59  cheshire
  87 Headers should use "extern" declarations, not "mDNSexport"
  88
  89 Revision 1.11  2004/04/14 23:09:28  ksekar
  90 Support for TSIG signed dynamic updates.
  91
  92 Revision 1.10  2004/03/13 01:57:33  ksekar
  93 <rdar://problem/3192546>: DynDNS: Dynamic update of service records
  94
  95 Revision 1.9  2004/02/21 08:56:58  bradley
  96 Wrap prototypes with extern "C" for C++ builds.
  97
  98 Revision 1.8  2004/02/06 23:04:18  ksekar
  99 Basic Dynamic Update support via mDNS_Register (dissabled via
 100 UNICAST_REGISTRATION #define)
 101
 102 Revision 1.7  2004/02/03 19:47:36  ksekar
 103 Added an asynchronous state machine mechanism to uDNS.c, including
 104 calls to find the parent zone for a domain name.  Changes include code
 105 in repository previously dissabled via "#if 0 incomplete".  Codepath
 106 is currently unused, and will be called to create update records, etc.
 107
 108 Revision 1.6  2004/01/27 20:15:22  cheshire
 109 <rdar://problem/3541288>: Time to prune obsolete code for listening on port 53
 110
 111 Revision 1.5  2004/01/24 03:40:56  cheshire
 112 Move mDNSAddrIsDNSMulticast() from DNSCommon.h to mDNSEmbeddedAPI.h so embedded clients can use it
 113
 114 Revision 1.4  2004/01/24 03:38:27  cheshire
 115 Fix minor syntactic error: Headers should use "extern" declarations, not "mDNSexport"
 116
 117 Revision 1.3  2004/01/23 23:23:14  ksekar
 118 Added TCP support for truncated unicast messages.
 119
 120 Revision 1.2  2004/01/21 21:12:23  cheshire
 121 Add missing newline at end of file to make Unix tools happier
 122
 123 Revision 1.1  2003/12/13 03:05:27  ksekar
 124 <rdar://problem/3192548>: DynDNS: Unicast query of service records
 125
 126
 127  */
 128
 129 #ifndef __DNSCOMMON_H_
 130 #define __DNSCOMMON_H_
 131
 132 #include "mDNSEmbeddedAPI.h"
 133
 134 #ifdef  __cplusplus
 135         extern "C" {
 136 #endif
 137
 138 // ***************************************************************************
 139 #if COMPILER_LIKES_PRAGMA_MARK
 140 #pragma mark - DNS Protocol Constants
 141 #endif
 142
 143 typedef enum
 144         {
 145         kDNSFlag0_QR_Mask     = 0x80,           // Query or response?
 146         kDNSFlag0_QR_Query    = 0x00,
 147         kDNSFlag0_QR_Response = 0x80,
 148
 149         kDNSFlag0_OP_Mask     = 0x78,           // Operation type
 150         kDNSFlag0_OP_StdQuery = 0x00,
 151         kDNSFlag0_OP_Iquery   = 0x08,
 152         kDNSFlag0_OP_Status   = 0x10,
 153         kDNSFlag0_OP_Unused3  = 0x18,
 154         kDNSFlag0_OP_Notify   = 0x20,
 155         kDNSFlag0_OP_Update   = 0x28,
 156
 157         kDNSFlag0_QROP_Mask   = kDNSFlag0_QR_Mask | kDNSFlag0_OP_Mask,
 158
 159         kDNSFlag0_AA          = 0x04,           // Authoritative Answer?
 160         kDNSFlag0_TC          = 0x02,           // Truncated?
 161         kDNSFlag0_RD          = 0x01,           // Recursion Desired?
 162         kDNSFlag1_RA          = 0x80,           // Recursion Available?
 163
 164         kDNSFlag1_Zero        = 0x40,           // Reserved; must be zero
 165         kDNSFlag1_AD          = 0x20,           // Authentic Data [RFC 2535]
 166         kDNSFlag1_CD          = 0x10,           // Checking Disabled [RFC 2535]
 167
 168         kDNSFlag1_RC          = 0x0F,           // Response code
 169         kDNSFlag1_RC_NoErr    = 0x00,
 170         kDNSFlag1_RC_FmtErr   = 0x01,
 171         kDNSFlag1_RC_SrvErr   = 0x02,
 172         kDNSFlag1_RC_NXDomain = 0x03,
 173         kDNSFlag1_RC_NotImpl  = 0x04,
 174         kDNSFlag1_RC_Refused  = 0x05,
 175         kDNSFlag1_RC_YXDomain = 0x06,
 176         kDNSFlag1_RC_YXRRSet  = 0x07,
 177         kDNSFlag1_RC_NXRRSet  = 0x08,
 178         kDNSFlag1_RC_NotAuth  = 0x09,
 179         kDNSFlag1_RC_NotZone  = 0x0A
 180         } DNS_Flags;
 181
 182 typedef enum
 183         {
 184         TSIG_ErrBadSig  = 16,
 185         TSIG_ErrBadKey  = 17,
 186         TSIG_ErrBadTime = 18
 187         } TSIG_ErrorCode;
 188
 189 // ***************************************************************************
 190 #if COMPILER_LIKES_PRAGMA_MARK
 191 #pragma mark -
 192 #pragma mark - General Utility Functions
 193 #endif
 194
 195 extern const NetworkInterfaceInfo *GetFirstActiveInterface(const NetworkInterfaceInfo *intf);
 196 extern mDNSInterfaceID GetNextActiveInterfaceID(const NetworkInterfaceInfo *intf);
 197
 198 extern mDNSu32 mDNSRandom(mDNSu32 max);
 199
 200
 201 // ***************************************************************************
 202 #if COMPILER_LIKES_PRAGMA_MARK
 203 #pragma mark -
 204 #pragma mark - Domain Name Utility Functions
 205 #endif
 206
 207 #define mdnsIsDigit(X)     ((X) >= '0' && (X) <= '9')
 208 #define mDNSIsUpperCase(X) ((X) >= 'A' && (X) <= 'Z')
 209 #define mDNSIsLowerCase(X) ((X) >= 'a' && (X) <= 'z')
 210 #define mdnsIsLetter(X)    (mDNSIsUpperCase(X) || mDNSIsLowerCase(X))
 211
 212 #define mdnsValidHostChar(X, notfirst, notlast) (mdnsIsLetter(X) || mdnsIsDigit(X) || ((notfirst) && (notlast) && (X) == '-') )
 213
 214 extern mDNSu16 CompressedDomainNameLength(const domainname *const name, const domainname *parent);
 215
 216 extern mDNSBool LabelContainsSuffix(const domainlabel *const name, const mDNSBool RichText);
 217 extern mDNSu32 RemoveLabelSuffix(domainlabel *name, mDNSBool RichText);
 218 extern void AppendLabelSuffix(domainlabel *name, mDNSu32 val, mDNSBool RichText);
 219 extern void mDNS_HostNameCallback(mDNS *const m, AuthRecord *const rr, mStatus result);
 220 #define ValidateDomainName(N) (DomainNameLength(N) <= MAX_DOMAIN_NAME)
 221
 222
 223 // ***************************************************************************
 224 #if COMPILER_LIKES_PRAGMA_MARK
 225 #pragma mark -
 226 #pragma mark - Resource Record Utility Functions
 227 #endif
 228
 229 extern mDNSu32 RDataHashValue(mDNSu16 const rdlength, const RDataBody *const rdb);
 230
 231 extern mDNSBool SameRData(const ResourceRecord *const r1, const ResourceRecord *const r2);
 232
 233 extern mDNSBool ResourceRecordAnswersQuestion(const ResourceRecord *const rr, const DNSQuestion *const q);
 234
 235 extern mDNSBool SameResourceRecord(ResourceRecord *r1, ResourceRecord *r2);
 236
 237 extern mDNSu16 GetRDLength(const ResourceRecord *const rr, mDNSBool estimate);
 238
 239 #define GetRRDomainNameTarget(RR) (                                                                          \
 240         ((RR)->rrtype == kDNSType_CNAME || (RR)->rrtype == kDNSType_PTR || (RR)->rrtype == kDNSType_NS)          \
 241                                                                          ? &(RR)->rdata->u.name       :          \
 242         ((RR)->rrtype == kDNSType_SRV                                  ) ? &(RR)->rdata->u.srv.target : mDNSNULL )
 243
 244 extern mDNSBool ValidateRData(const mDNSu16 rrtype, const mDNSu16 rdlength, const RData *const rd);
 245 #define LocalRecordReady(X) ((X)->resrec.RecordType != kDNSRecordTypeUnique && (X)->resrec.RecordType != kDNSRecordTypeDeregistering)
 246
 247
 248 // ***************************************************************************
 249 #if COMPILER_LIKES_PRAGMA_MARK
 250 #pragma mark -
 251 #pragma mark -
 252 #pragma mark - DNS Message Creation Functions
 253 #endif
 254
 255 extern void InitializeDNSMessage(DNSMessageHeader *h, mDNSOpaque16 id, mDNSOpaque16 flags);
 256 extern const mDNSu8 *FindCompressionPointer(const mDNSu8 *const base, const mDNSu8 *const end, const mDNSu8 *const domname);
 257
 258 extern mDNSu8 *putDomainNameAsLabels(const DNSMessage *const msg, mDNSu8 *ptr, const mDNSu8 *const limit, const domainname *const name);
 259
 260 extern mDNSu8 *putRData(const DNSMessage *const msg, mDNSu8 *ptr, const mDNSu8 *const limit, ResourceRecord *rr);
 261
 262 // If we have a single large record to put in the packet, then we allow the packet to be up to 9K bytes,
 263 // but in the normal case we try to keep the packets below 1500 to avoid IP fragmentation on standard Ethernet
 264
 265 extern mDNSu8 *PutResourceRecordTTLWithLimit(DNSMessage *const msg, mDNSu8 *ptr, mDNSu16 *count, ResourceRecord *rr, mDNSu32 ttl, const mDNSu8 *limit);
 266
 267 #define PutResourceRecordTTL(msg, ptr, count, rr, ttl) PutResourceRecordTTLWithLimit((msg), (ptr), (count), (rr), (ttl), \
 268         ((msg)->h.numAnswers || (msg)->h.numAuthorities || (msg)->h.numAdditionals) ? (msg)->data + NormalMaxDNSMessageData : (msg)->data + AbsoluteMaxDNSMessageData)
 269
 270 #define PutResourceRecordTTLJumbo(msg, ptr, count, rr, ttl) PutResourceRecordTTLWithLimit((msg), (ptr), (count), (rr), (ttl), \
 271         (msg)->data + AbsoluteMaxDNSMessageData)
 272
 273 extern mDNSu8 *PutResourceRecordCappedTTL(DNSMessage *const msg, mDNSu8 *ptr, mDNSu16 *count, ResourceRecord *rr, mDNSu32 maxttl);
 274
 275 extern mDNSu8 *putEmptyResourceRecord(DNSMessage *const msg, mDNSu8 *ptr, const mDNSu8 *const limit, mDNSu16 *count, const AuthRecord *rr);
 276
 277 extern mDNSu8 *putQuestion(DNSMessage *const msg, mDNSu8 *ptr, const mDNSu8 *const limit, const domainname *const name, mDNSu16 rrtype, mDNSu16 rrclass);
 278
 279 extern mDNSu8 *putZone(DNSMessage *const msg, mDNSu8 *ptr, mDNSu8 *limit, const domainname *zone, mDNSOpaque16 zoneClass);
 280
 281 extern mDNSu8 *putPrereqNameNotInUse(domainname *name, DNSMessage *msg, mDNSu8 *ptr, mDNSu8 *end);
 282
 283 extern mDNSu8 *putDeletionRecord(DNSMessage *msg, mDNSu8 *ptr, ResourceRecord *rr);
 284
 285 extern  mDNSu8 *putDeleteRRSet(DNSMessage *msg, mDNSu8 *ptr, const domainname *name, mDNSu16 rrtype);
 286
 287 extern mDNSu8 *putDeleteAllRRSets(DNSMessage *msg, mDNSu8 *ptr, const domainname *name);
 288
 289 extern mDNSu8 *putUpdateLease(DNSMessage *msg, mDNSu8 *end, mDNSu32 lease);
 290
 291 #define PutResourceRecord(MSG, P, C, RR) PutResourceRecordTTL((MSG), (P), (C), (RR), (RR)->rroriginalttl)
 292
 293
 294 // ***************************************************************************
 295 #if COMPILER_LIKES_PRAGMA_MARK
 296 #pragma mark -
 297 #pragma mark - DNS Message Parsing Functions
 298 #endif
 299
 300 extern mDNSu32 DomainNameHashValue(const domainname *const name);
 301
 302 extern void SetNewRData(ResourceRecord *const rr, RData *NewRData, mDNSu16 rdlength);
 303
 304
 305 extern const mDNSu8 *skipDomainName(const DNSMessage *const msg, const mDNSu8 *ptr, const mDNSu8 *const end);
 306
 307 extern const mDNSu8 *getDomainName(const DNSMessage *const msg, const mDNSu8 *ptr, const mDNSu8 *const end,
 308         domainname *const name);
 309
 310 extern const mDNSu8 *skipResourceRecord(const DNSMessage *msg, const mDNSu8 *ptr, const mDNSu8 *end);
 311
 312 extern const mDNSu8 *GetLargeResourceRecord(mDNS *const m, const DNSMessage * const msg, const mDNSu8 *ptr,
 313     const mDNSu8 * const end, const mDNSInterfaceID InterfaceID, mDNSu8 RecordType, LargeCacheRecord *largecr);
 314
 315 extern const mDNSu8 *skipQuestion(const DNSMessage *msg, const mDNSu8 *ptr, const mDNSu8 *end);
 316
 317 extern const mDNSu8 *getQuestion(const DNSMessage *msg, const mDNSu8 *ptr, const mDNSu8 *end, const mDNSInterfaceID InterfaceID,
 318         DNSQuestion *question);
 319
 320 extern const mDNSu8 *LocateAnswers(const DNSMessage *const msg, const mDNSu8 *const end);
 321
 322 extern const mDNSu8 *LocateAuthorities(const DNSMessage *const msg, const mDNSu8 *const end);
 323
 324 extern const mDNSu8 *LocateAdditionals(const DNSMessage *const msg, const mDNSu8 *const end);
 325
 326 // ***************************************************************************
 327 #if COMPILER_LIKES_PRAGMA_MARK
 328 #pragma mark -
 329 #pragma mark -
 330 #pragma mark - Packet Sending Functions
 331 #endif
 332
 333 extern mStatus mDNSSendDNSMessage(const mDNS *const m, DNSMessage *const msg, mDNSu8 *end,
 334         mDNSInterfaceID InterfaceID, const mDNSAddr *dst, mDNSIPPort dstport, int sd, uDNS_AuthInfo *authInfo);
 335
 336 // ***************************************************************************
 337 #if COMPILER_LIKES_PRAGMA_MARK
 338 #pragma mark -
 339 #pragma mark - RR List Management & Task Management
 340 #endif
 341
 342 extern void mDNS_Lock(mDNS *const m);
 343 extern void mDNS_Unlock(mDNS *const m);
 344
 345 #ifdef  __cplusplus
 346         }
 347 #endif
 348
 349 #endif // __DNSCOMMON_H_