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 1.32  2005/03/21 00:33:51  shersche
  27 <rdar://problem/4021486> Fix build warnings on Win32 platform
  28
  29 Revision 1.31  2005/02/18 00:43:11  cheshire
  30 <rdar://problem/4010245> mDNSResponder should auto-truncate service names that are too long
  31
  32 Revision 1.30  2005/01/19 03:12:44  cheshire
  33 Move LocalRecordReady() macro from mDNS.c to DNSCommon.h
  34
  35 Revision 1.29  2004/12/15 02:11:22  ksekar
  36 <rdar://problem/3917317> Don't check for Dynamic DNS hostname uniqueness
  37
  38 Revision 1.28  2004/12/06 21:15:22  ksekar
  39 <rdar://problem/3884386> mDNSResponder crashed in CheckServiceRegistrations
  40
  41 Revision 1.27  2004/12/03 07:20:50  ksekar
  42 <rdar://problem/3674208> Wide-Area: Registration of large TXT record fails
  43
  44 Revision 1.26  2004/12/03 05:18:33  ksekar
  45 <rdar://problem/3810596> mDNSResponder needs to return more specific TSIG errors
  46
  47 Revision 1.25  2004/10/26 03:52:02  cheshire
  48 Update checkin comments
  49
  50 Revision 1.24  2004/10/23 01:16:00  cheshire
  51 <rdar://problem/3851677> uDNS operations not always reliable on multi-homed hosts
  52
  53 Revision 1.23  2004/10/03 23:18:58  cheshire
  54 Move address comparison macros from DNSCommon.h to mDNSEmbeddedAPI.h
  55
  56 Revision 1.22  2004/09/30 00:24:56  ksekar
  57 <rdar://problem/3695802> Dynamically update default registration domains on config change
  58
  59 Revision 1.21  2004/09/17 01:08:48  cheshire
  60 Renamed mDNSClientAPI.h to mDNSEmbeddedAPI.h
  61   The name "mDNSClientAPI.h" is misleading to new developers looking at this code. The interfaces
  62   declared in that file are ONLY appropriate to single-address-space embedded applications.
  63   For clients on general-purpose computers, the interfaces defined in dns_sd.h should be used.
  64
  65 Revision 1.20  2004/09/17 00:49:51  cheshire
  66 Get rid of now-unused GetResourceRecord -- the correct (safe) routine to use
  67 is GetLargeResourceRecord
  68
  69 Revision 1.19  2004/09/16 21:59:15  cheshire
  70 For consistency with zerov6Addr, rename zeroIPAddr to zerov4Addr
  71
  72 Revision 1.18  2004/09/16 02:29:39  cheshire
  73 Moved mDNS_Lock/mDNS_Unlock to DNSCommon.c; Added necessary locking around
  74 uDNS_ReceiveMsg, uDNS_StartQuery, uDNS_UpdateRecord, uDNS_RegisterService
  75
  76 Revision 1.17  2004/09/14 23:27:46  cheshire
  77 Fix compile errors
  78
  79 Revision 1.16  2004/08/13 23:46:58  cheshire
  80 "asyncronous" -> "asynchronous"
  81
  82 Revision 1.15  2004/08/10 23:19:14  ksekar
  83 <rdar://problem/3722542>: DNS Extension daemon for Wide Area Service Discovery
  84 Moved routines/constants to allow extern access for garbage collection daemon
  85
  86 Revision 1.14  2004/05/28 23:42:36  ksekar
  87 <rdar://problem/3258021>: Feature: DNS server->client notification on record changes (#7805)
  88
  89 Revision 1.13  2004/05/18 23:51:25  cheshire
  90 Tidy up all checkin comments to use consistent "<rdar://problem/xxxxxxx>" format for bug numbers
  91
  92 Revision 1.12  2004/04/22 04:03:59  cheshire
  93 Headers should use "extern" declarations, not "mDNSexport"
  94
  95 Revision 1.11  2004/04/14 23:09:28  ksekar
  96 Support for TSIG signed dynamic updates.
  97
  98 Revision 1.10  2004/03/13 01:57:33  ksekar
  99 <rdar://problem/3192546>: DynDNS: Dynamic update of service records
 100
 101 Revision 1.9  2004/02/21 08:56:58  bradley
 102 Wrap prototypes with extern "C" for C++ builds.
 103
 104 Revision 1.8  2004/02/06 23:04:18  ksekar
 105 Basic Dynamic Update support via mDNS_Register (dissabled via
 106 UNICAST_REGISTRATION #define)
 107
 108 Revision 1.7  2004/02/03 19:47:36  ksekar
 109 Added an asynchronous state machine mechanism to uDNS.c, including
 110 calls to find the parent zone for a domain name.  Changes include code
 111 in repository previously dissabled via "#if 0 incomplete".  Codepath
 112 is currently unused, and will be called to create update records, etc.
 113
 114 Revision 1.6  2004/01/27 20:15:22  cheshire
 115 <rdar://problem/3541288>: Time to prune obsolete code for listening on port 53
 116
 117 Revision 1.5  2004/01/24 03:40:56  cheshire
 118 Move mDNSAddrIsDNSMulticast() from DNSCommon.h to mDNSEmbeddedAPI.h so embedded clients can use it
 119
 120 Revision 1.4  2004/01/24 03:38:27  cheshire
 121 Fix minor syntactic error: Headers should use "extern" declarations, not "mDNSexport"
 122
 123 Revision 1.3  2004/01/23 23:23:14  ksekar
 124 Added TCP support for truncated unicast messages.
 125
 126 Revision 1.2  2004/01/21 21:12:23  cheshire
 127 Add missing newline at end of file to make Unix tools happier
 128
 129 Revision 1.1  2003/12/13 03:05:27  ksekar
 130 <rdar://problem/3192548>: DynDNS: Unicast query of service records
 131
 132
 133  */
 134
 135 #ifndef __DNSCOMMON_H_
 136 #define __DNSCOMMON_H_
 137
 138 #include "mDNSEmbeddedAPI.h"
 139
 140 #ifdef  __cplusplus
 141         extern "C" {
 142 #endif
 143
 144 // ***************************************************************************
 145 #if COMPILER_LIKES_PRAGMA_MARK
 146 #pragma mark - DNS Protocol Constants
 147 #endif
 148
 149 typedef enum
 150         {
 151         kDNSFlag0_QR_Mask     = 0x80,           // Query or response?
 152         kDNSFlag0_QR_Query    = 0x00,
 153         kDNSFlag0_QR_Response = 0x80,
 154
 155         kDNSFlag0_OP_Mask     = 0x78,           // Operation type
 156         kDNSFlag0_OP_StdQuery = 0x00,
 157         kDNSFlag0_OP_Iquery   = 0x08,
 158         kDNSFlag0_OP_Status   = 0x10,
 159         kDNSFlag0_OP_Unused3  = 0x18,
 160         kDNSFlag0_OP_Notify   = 0x20,
 161         kDNSFlag0_OP_Update   = 0x28,
 162
 163         kDNSFlag0_QROP_Mask   = kDNSFlag0_QR_Mask | kDNSFlag0_OP_Mask,
 164
 165         kDNSFlag0_AA          = 0x04,           // Authoritative Answer?
 166         kDNSFlag0_TC          = 0x02,           // Truncated?
 167         kDNSFlag0_RD          = 0x01,           // Recursion Desired?
 168         kDNSFlag1_RA          = 0x80,           // Recursion Available?
 169
 170         kDNSFlag1_Zero        = 0x40,           // Reserved; must be zero
 171         kDNSFlag1_AD          = 0x20,           // Authentic Data [RFC 2535]
 172         kDNSFlag1_CD          = 0x10,           // Checking Disabled [RFC 2535]
 173
 174         kDNSFlag1_RC          = 0x0F,           // Response code
 175         kDNSFlag1_RC_NoErr    = 0x00,
 176         kDNSFlag1_RC_FmtErr   = 0x01,
 177         kDNSFlag1_RC_SrvErr   = 0x02,
 178         kDNSFlag1_RC_NXDomain = 0x03,
 179         kDNSFlag1_RC_NotImpl  = 0x04,
 180         kDNSFlag1_RC_Refused  = 0x05,
 181         kDNSFlag1_RC_YXDomain = 0x06,
 182         kDNSFlag1_RC_YXRRSet  = 0x07,
 183         kDNSFlag1_RC_NXRRSet  = 0x08,
 184         kDNSFlag1_RC_NotAuth  = 0x09,
 185         kDNSFlag1_RC_NotZone  = 0x0A
 186         } DNS_Flags;
 187
 188 typedef enum
 189         {
 190         TSIG_ErrBadSig  = 16,
 191         TSIG_ErrBadKey  = 17,
 192         TSIG_ErrBadTime = 18
 193         } TSIG_ErrorCode;
 194
 195 // ***************************************************************************
 196 #if COMPILER_LIKES_PRAGMA_MARK
 197 #pragma mark -
 198 #pragma mark - General Utility Functions
 199 #endif
 200
 201 extern const NetworkInterfaceInfo *GetFirstActiveInterface(const NetworkInterfaceInfo *intf);
 202 extern mDNSInterfaceID GetNextActiveInterfaceID(const NetworkInterfaceInfo *intf);
 203
 204 extern mDNSu32 mDNSRandom(mDNSu32 max);
 205
 206
 207 // ***************************************************************************
 208 #if COMPILER_LIKES_PRAGMA_MARK
 209 #pragma mark -
 210 #pragma mark - Domain Name Utility Functions
 211 #endif
 212
 213 #define mdnsIsDigit(X)     ((X) >= '0' && (X) <= '9')
 214 #define mDNSIsUpperCase(X) ((X) >= 'A' && (X) <= 'Z')
 215 #define mDNSIsLowerCase(X) ((X) >= 'a' && (X) <= 'z')
 216 #define mdnsIsLetter(X)    (mDNSIsUpperCase(X) || mDNSIsLowerCase(X))
 217
 218 #define mdnsValidHostChar(X, notfirst, notlast) (mdnsIsLetter(X) || mdnsIsDigit(X) || ((notfirst) && (notlast) && (X) == '-') )
 219
 220 extern mDNSu16 CompressedDomainNameLength(const domainname *const name, const domainname *parent);
 221
 222 extern mDNSu32 TruncateUTF8ToLength(mDNSu8 *string, mDNSu32 length, mDNSu32 max);
 223 extern mDNSBool LabelContainsSuffix(const domainlabel *const name, const mDNSBool RichText);
 224 extern mDNSu32 RemoveLabelSuffix(domainlabel *name, mDNSBool RichText);
 225 extern void AppendLabelSuffix(domainlabel *name, mDNSu32 val, mDNSBool RichText);
 226 extern void mDNS_HostNameCallback(mDNS *const m, AuthRecord *const rr, mStatus result);
 227 #define ValidateDomainName(N) (DomainNameLength(N) <= MAX_DOMAIN_NAME)
 228
 229
 230 // ***************************************************************************
 231 #if COMPILER_LIKES_PRAGMA_MARK
 232 #pragma mark -
 233 #pragma mark - Resource Record Utility Functions
 234 #endif
 235
 236 extern mDNSu32 RDataHashValue(mDNSu16 const rdlength, const RDataBody *const rdb);
 237
 238 extern mDNSBool SameRData(const ResourceRecord *const r1, const ResourceRecord *const r2);
 239
 240 extern mDNSBool ResourceRecordAnswersQuestion(const ResourceRecord *const rr, const DNSQuestion *const q);
 241
 242 extern mDNSBool SameResourceRecord(ResourceRecord *r1, ResourceRecord *r2);
 243
 244 extern mDNSu16 GetRDLength(const ResourceRecord *const rr, mDNSBool estimate);
 245
 246 #define GetRRDomainNameTarget(RR) (                                                                          \
 247         ((RR)->rrtype == kDNSType_CNAME || (RR)->rrtype == kDNSType_PTR || (RR)->rrtype == kDNSType_NS)          \
 248                                                                          ? &(RR)->rdata->u.name       :          \
 249         ((RR)->rrtype == kDNSType_SRV                                  ) ? &(RR)->rdata->u.srv.target : mDNSNULL )
 250
 251 extern mDNSBool ValidateRData(const mDNSu16 rrtype, const mDNSu16 rdlength, const RData *const rd);
 252 #define LocalRecordReady(X) ((X)->resrec.RecordType != kDNSRecordTypeUnique && (X)->resrec.RecordType != kDNSRecordTypeDeregistering)
 253
 254
 255 // ***************************************************************************
 256 #if COMPILER_LIKES_PRAGMA_MARK
 257 #pragma mark -
 258 #pragma mark -
 259 #pragma mark - DNS Message Creation Functions
 260 #endif
 261
 262 extern void InitializeDNSMessage(DNSMessageHeader *h, mDNSOpaque16 id, mDNSOpaque16 flags);
 263 extern const mDNSu8 *FindCompressionPointer(const mDNSu8 *const base, const mDNSu8 *const end, const mDNSu8 *const domname);
 264
 265 extern mDNSu8 *putDomainNameAsLabels(const DNSMessage *const msg, mDNSu8 *ptr, const mDNSu8 *const limit, const domainname *const name);
 266
 267 extern mDNSu8 *putRData(const DNSMessage *const msg, mDNSu8 *ptr, const mDNSu8 *const limit, ResourceRecord *rr);
 268
 269 // If we have a single large record to put in the packet, then we allow the packet to be up to 9K bytes,
 270 // but in the normal case we try to keep the packets below 1500 to avoid IP fragmentation on standard Ethernet
 271
 272 extern mDNSu8 *PutResourceRecordTTLWithLimit(DNSMessage *const msg, mDNSu8 *ptr, mDNSu16 *count, ResourceRecord *rr, mDNSu32 ttl, const mDNSu8 *limit);
 273
 274 #define PutResourceRecordTTL(msg, ptr, count, rr, ttl) PutResourceRecordTTLWithLimit((msg), (ptr), (count), (rr), (ttl), \
 275         ((msg)->h.numAnswers || (msg)->h.numAuthorities || (msg)->h.numAdditionals) ? (msg)->data + NormalMaxDNSMessageData : (msg)->data + AbsoluteMaxDNSMessageData)
 276
 277 #define PutResourceRecordTTLJumbo(msg, ptr, count, rr, ttl) PutResourceRecordTTLWithLimit((msg), (ptr), (count), (rr), (ttl), \
 278         (msg)->data + AbsoluteMaxDNSMessageData)
 279
 280 extern mDNSu8 *PutResourceRecordCappedTTL(DNSMessage *const msg, mDNSu8 *ptr, mDNSu16 *count, ResourceRecord *rr, mDNSu32 maxttl);
 281
 282 extern mDNSu8 *putEmptyResourceRecord(DNSMessage *const msg, mDNSu8 *ptr, const mDNSu8 *const limit, mDNSu16 *count, const AuthRecord *rr);
 283
 284 extern mDNSu8 *putQuestion(DNSMessage *const msg, mDNSu8 *ptr, const mDNSu8 *const limit, const domainname *const name, mDNSu16 rrtype, mDNSu16 rrclass);
 285
 286 extern mDNSu8 *putZone(DNSMessage *const msg, mDNSu8 *ptr, mDNSu8 *limit, const domainname *zone, mDNSOpaque16 zoneClass);
 287
 288 extern mDNSu8 *putPrereqNameNotInUse(domainname *name, DNSMessage *msg, mDNSu8 *ptr, mDNSu8 *end);
 289
 290 extern mDNSu8 *putDeletionRecord(DNSMessage *msg, mDNSu8 *ptr, ResourceRecord *rr);
 291
 292 extern  mDNSu8 *putDeleteRRSet(DNSMessage *msg, mDNSu8 *ptr, const domainname *name, mDNSu16 rrtype);
 293
 294 extern mDNSu8 *putDeleteAllRRSets(DNSMessage *msg, mDNSu8 *ptr, const domainname *name);
 295
 296 extern mDNSu8 *putUpdateLease(DNSMessage *msg, mDNSu8 *end, mDNSu32 lease);
 297
 298 #define PutResourceRecord(MSG, P, C, RR) PutResourceRecordTTL((MSG), (P), (C), (RR), (RR)->rroriginalttl)
 299
 300
 301 // ***************************************************************************
 302 #if COMPILER_LIKES_PRAGMA_MARK
 303 #pragma mark -
 304 #pragma mark - DNS Message Parsing Functions
 305 #endif
 306
 307 extern mDNSu32 DomainNameHashValue(const domainname *const name);
 308
 309 extern void SetNewRData(ResourceRecord *const rr, RData *NewRData, mDNSu16 rdlength);
 310
 311
 312 extern const mDNSu8 *skipDomainName(const DNSMessage *const msg, const mDNSu8 *ptr, const mDNSu8 *const end);
 313
 314 extern const mDNSu8 *getDomainName(const DNSMessage *const msg, const mDNSu8 *ptr, const mDNSu8 *const end,
 315         domainname *const name);
 316
 317 extern const mDNSu8 *skipResourceRecord(const DNSMessage *msg, const mDNSu8 *ptr, const mDNSu8 *end);
 318
 319 extern const mDNSu8 *GetLargeResourceRecord(mDNS *const m, const DNSMessage * const msg, const mDNSu8 *ptr,
 320     const mDNSu8 * end, const mDNSInterfaceID InterfaceID, mDNSu8 RecordType, LargeCacheRecord *largecr);
 321
 322 extern const mDNSu8 *skipQuestion(const DNSMessage *msg, const mDNSu8 *ptr, const mDNSu8 *end);
 323
 324 extern const mDNSu8 *getQuestion(const DNSMessage *msg, const mDNSu8 *ptr, const mDNSu8 *end, const mDNSInterfaceID InterfaceID,
 325         DNSQuestion *question);
 326
 327 extern const mDNSu8 *LocateAnswers(const DNSMessage *const msg, const mDNSu8 *const end);
 328
 329 extern const mDNSu8 *LocateAuthorities(const DNSMessage *const msg, const mDNSu8 *const end);
 330
 331 extern const mDNSu8 *LocateAdditionals(const DNSMessage *const msg, const mDNSu8 *const end);
 332
 333 // ***************************************************************************
 334 #if COMPILER_LIKES_PRAGMA_MARK
 335 #pragma mark -
 336 #pragma mark -
 337 #pragma mark - Packet Sending Functions
 338 #endif
 339
 340 extern mStatus mDNSSendDNSMessage(const mDNS *const m, DNSMessage *const msg, mDNSu8 *end,
 341         mDNSInterfaceID InterfaceID, const mDNSAddr *dst, mDNSIPPort dstport, int sd, uDNS_AuthInfo *authInfo);
 342
 343 // ***************************************************************************
 344 #if COMPILER_LIKES_PRAGMA_MARK
 345 #pragma mark -
 346 #pragma mark - RR List Management & Task Management
 347 #endif
 348
 349 extern void mDNS_Lock(mDNS *const m);
 350 extern void mDNS_Unlock(mDNS *const m);
 351
 352 #ifdef  __cplusplus
 353         }
 354 #endif
 355
 356 #endif // __DNSCOMMON_H_