1 /* -*- Mode: C; tab-width: 4 -*-
2  *
3  * Copyright (c) 2002-2003 Apple Computer, Inc. All rights reserved.
4  *
5  * Licensed under the Apache License, Version 2.0 (the "License");
6  * you may not use this file except in compliance with the License.
7  * You may obtain a copy of the License at
8  *
9  *     http://www.apache.org/licenses/LICENSE-2.0
10  *
11  * Unless required by applicable law or agreed to in writing, software
12  * distributed under the License is distributed on an "AS IS" BASIS,
13  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14  * See the License for the specific language governing permissions and
15  * limitations under the License.
16 
17 
18    NOTE:
19    If you're building an application that uses DNS Service Discovery
20    this is probably NOT the header file you're looking for.
21    In most cases you will want to use /usr/include/dns_sd.h instead.
22 
23    This header file defines the lowest level raw interface to mDNSCore,
24    which is appropriate *only* on tiny embedded systems where everything
25    runs in a single address space and memory is extremely constrained.
26    All the APIs here are malloc-free, which means that the caller is
27    responsible for passing in a pointer to the relevant storage that
28    will be used in the execution of that call, and (when called with
29    correct parameters) all the calls are guaranteed to succeed. There
30    is never a case where a call can suffer intermittent failures because
31    the implementation calls malloc() and sometimes malloc() returns NULL
32    because memory is so limited that no more is available.
33    This is primarily for devices that need to have precisely known fixed
34    memory requirements, with absolutely no uncertainty or run-time variation,
35    but that certainty comes at a cost of more difficult programming.
36 
37    For applications running on general-purpose desktop operating systems
38    (Mac OS, Linux, Solaris, Windows, etc.) the API you should use is
39    /usr/include/dns_sd.h, which defines the API by which multiple
40    independent client processes communicate their DNS Service Discovery
41    requests to a single "mdnsd" daemon running in the background.
42 
43    Even on platforms that don't run multiple independent processes in
44    multiple independent address spaces, you can still use the preferred
45    dns_sd.h APIs by linking in "dnssd_clientshim.c", which implements
46    the standard "dns_sd.h" API calls, allocates any required storage
47    using malloc(), and then calls through to the low-level malloc-free
48    mDNSCore routines defined here. This has the benefit that even though
49    you're running on a small embedded system with a single address space,
50    you can still use the exact same client C code as you'd use on a
51    general-purpose desktop system.
52 
53 
54     Change History (most recent first):
55 
56 Log: mDNSEmbeddedAPI.h,v $
57 Revision 1.573  2009/06/30 18:17:45  herscher
58 Add to 64 bit macro check for 64 bit Windows OSes
59 
60 Revision 1.572  2009/06/27 00:52:27  cheshire
61 <rdar://problem/6959273> mDNSResponder taking up 13% CPU with 400 KBps incoming bonjour requests
62 Removed overly-complicate and ineffective multi-packet known-answer snooping code
63 (Bracketed it with "#if ENABLE_MULTI_PACKET_QUERY_SNOOPING" for now; will delete actual code later)
64 
65 Revision 1.571  2009/06/26 01:55:54  cheshire
66 <rdar://problem/6890712> mDNS: iChat's Buddy photo always appears as the "shadow person" over Bonjour
67 Additional refinements -- except for the case of explicit queries for record types we don't have (for names we own),
68 add additional NSEC records only when there's space to do that without having to generate an additional packet
69 
70 Revision 1.570  2009/06/24 22:14:21  cheshire
71 <rdar://problem/6911445> Plugging and unplugging the power cable shouldn't cause a network change event
72 
73 Revision 1.569  2009/06/03 23:07:12  cheshire
74 <rdar://problem/6890712> mDNS: iChat's Buddy photo always appears as the "shadow person" over Bonjour
75 Large records were not being added in cases where an NSEC record was also required
76 
77 Revision 1.568  2009/05/19 22:37:04  cheshire
78 <rdar://problem/6903507> Sleep Proxy: Retransmission logic not working reliably on quiet networks
79 Added NextScheduledSPRetry field
80 
81 Revision 1.567  2009/05/13 17:25:33  mkrochma
82 <rdar://problem/6879926> Should not schedule maintenance wake when machine has no advertised services
83 Sleep proxy client should only look for services being advertised via Multicast
84 
85 Revision 1.566  2009/05/12 23:09:24  cheshire
86 <rdar://problem/6879926> Should not schedule maintenance wake when machine has no advertised services
87 Declare mDNSCoreHaveAdvertisedServices routine so it can be called from daemon.c
88 
89 Revision 1.565  2009/05/09 00:10:58  jessic2
90 Change expected size of NetworkInterfaceInfo to fix build failure
91 
92 Revision 1.564  2009/05/07 23:31:26  cheshire
93 <rdar://problem/6601427> Sleep Proxy: Retransmit and retry Sleep Proxy Server requests
94 Added NextSPSAttempt and NextSPSAttemptTime fields to NetworkInterfaceInfo_struct
95 
96 Revision 1.563  2009/04/24 21:06:38  cheshire
97 Added comment about UDP length field (includes UDP header, so minimum value is 8 bytes)
98 
99 Revision 1.562  2009/04/24 00:22:23  cheshire
100 <rdar://problem/3476350> Return negative answers when host knows authoritatively that no answer exists
101 Added definition of rdataNSEC
102 
103 Revision 1.561  2009/04/23 22:06:29  cheshire
104 Added CacheRecord and InterfaceID parameters to MakeNegativeCacheRecord, in preparation for:
105 <rdar://problem/3476350> Return negative answers when host knows authoritatively that no answer exists
106 
107 Revision 1.560  2009/04/23 21:54:50  cheshire
108 Updated comments
109 
110 Revision 1.559  2009/04/22 00:37:38  cheshire
111 <rdar://problem/6814427> Remove unused kDNSType_MAC
112 
113 Revision 1.558  2009/04/21 23:36:25  cheshire
114 <rdar://problem/6814427> Remove unused kDNSType_MAC
115 
116 Revision 1.557  2009/04/15 20:42:51  mcguire
117 <rdar://problem/6768947> uDNS: Treat RCODE 5 (Refused) responses as failures
118 
119 Revision 1.556  2009/04/11 00:19:43  jessic2
120 <rdar://problem/4426780> Daemon: Should be able to turn on LogOperation dynamically
121 
122 Revision 1.555  2009/04/01 21:12:27  herscher
123 <rdar://problem/5925472> Current Bonjour code does not compile on Windows.
124 
125 Revision 1.554  2009/04/01 17:50:11  mcguire
126 cleanup mDNSRandom
127 
128 Revision 1.553  2009/03/26 03:59:00  jessic2
129 Changes for <rdar://problem/6492552&6492593&6492609&6492613&6492628&6492640&6492699>
130 
131 Revision 1.552  2009/03/20 23:53:03  jessic2
132 <rdar://problem/6646228> SIGHUP should restart all in-progress queries
133 
134 Revision 1.551  2009/03/18 20:41:04  cheshire
135 Added definition of the all-ones mDNSOpaque16 ID
136 
137 Revision 1.550  2009/03/17 19:10:29  mcguire
138 Fix sizechecks for x86_64
139 
140 Revision 1.549  2009/03/17 01:22:56  cheshire
141 <rdar://problem/6601427> Sleep Proxy: Retransmit and retry Sleep Proxy Server requests
142 Initial support for resolving up to three Sleep Proxies in parallel
143 
144 Revision 1.548  2009/03/14 01:42:56  mcguire
145 <rdar://problem/5457116> BTMM: Fix issues with multiple .Mac accounts on the same machine
146 
147 Revision 1.547  2009/03/10 01:14:30  cheshire
148 Sleep Proxies with invalid names need to be ignored (score 10000),
149 not treated as "Sleep Proxy of last resort" (score 9999)
150 
151 Revision 1.546  2009/03/06 23:51:51  mcguire
152 Fix broken build by defining DiscardPort
153 
154 Revision 1.545  2009/03/06 22:39:23  cheshire
155 <rdar://problem/6655850> Ignore prototype base stations when picking Sleep Proxy to register with
156 
157 Revision 1.544  2009/03/04 01:33:30  cheshire
158 Add m->ProxyRecords counter
159 
160 Revision 1.543  2009/03/03 23:04:43  cheshire
161 For clarity, renamed "MAC" field to "HMAC" (Host MAC, as opposed to Interface MAC)
162 
163 Revision 1.542  2009/03/03 22:51:53  cheshire
164 <rdar://problem/6504236> Sleep Proxy: Waking on same network but different interface will cause conflicts
165 
166 Revision 1.541  2009/03/03 00:45:19  cheshire
167 Added m->PrimaryMAC field
168 
169 Revision 1.540  2009/02/27 02:56:57  cheshire
170 Moved struct SearchListElem definition from uDNS.c into mDNSEmbeddedAPI.h
171 
172 Revision 1.539  2009/02/17 23:29:01  cheshire
173 Throttle logging to a slower rate when running on SnowLeopard
174 
175 Revision 1.538  2009/02/11 02:31:57  cheshire
176 Moved SystemWakeOnLANEnabled from mDNSMacOSX.h, so it's accessible to mDNSCore routines
177 
178 Revision 1.537  2009/02/07 02:51:48  cheshire
179 <rdar://problem/6084043> Sleep Proxy: Need to adopt IOPMConnection
180 Added new functions and timing variables
181 
182 Revision 1.536  2009/01/30 23:50:31  cheshire
183 Added LastLabel() routine to get the last label of a domainname
184 
185 Revision 1.535  2009/01/23 00:38:36  mcguire
186 <rdar://problem/5570906> BTMM: Doesn't work with Linksys WRT54GS firmware 4.71.1
187 
188 Revision 1.534  2009/01/22 02:14:25  cheshire
189 <rdar://problem/6515626> Sleep Proxy: Set correct target MAC address, instead of all zeroes
190 
191 Revision 1.533  2009/01/21 03:43:57  mcguire
192 <rdar://problem/6511765> BTMM: Add support for setting kDNSServiceErr_NATPortMappingDisabled in DynamicStore
193 
194 Revision 1.532  2009/01/16 19:50:36  cheshire
195 Oops. Fixed definition of SleepProxyServiceType.
196 
197 Revision 1.531  2009/01/16 19:48:09  cheshire
198 Added definition of SleepProxyServiceType
199 
200 Revision 1.530  2009/01/15 00:22:49  mcguire
201 <rdar://problem/6437092> NAT-PMP: mDNSResponder needs to listen on 224.0.0.1:5350/UDP with REUSEPORT
202 
203 Revision 1.529  2009/01/13 00:31:44  cheshire
204 Fixed off-by-one error in computing the implicit limit pointer in the "DomainNameLength(name)" macro
205 
206 Revision 1.528  2009/01/10 01:43:52  cheshire
207 Changed misleading function name 'AnsweredLOQ' to more informative 'AnsweredLocalQ'
208 
209 Revision 1.527  2008/12/12 01:23:19  cheshire
210 Added m->SPSProxyListChanged state variable to flag when we need to update our BPF filter program
211 
212 Revision 1.526  2008/12/12 00:51:14  cheshire
213 Added structure definitions for IPv6Header, etc.
214 
215 Revision 1.525  2008/12/10 02:18:31  cheshire
216 Increased MaxMsg to 160 for showing longer TXT records in SIGINFO output
217 
218 Revision 1.524  2008/12/10 01:49:39  cheshire
219 Fixes for alignment issues on ARMv5
220 
221 Revision 1.523  2008/12/05 02:35:24  mcguire
222 <rdar://problem/6107390> Write to the DynamicStore when a Sleep Proxy server is available on the network
223 
224 Revision 1.522  2008/12/04 21:08:51  mcguire
225 <rdar://problem/6116863> mDNS: Provide mechanism to disable Multicast advertisements
226 
227 Revision 1.521  2008/12/04 02:19:24  cheshire
228 Updated comment
229 
230 Revision 1.520  2008/11/26 20:28:05  cheshire
231 Added new SSHPort constant
232 
233 Revision 1.519  2008/11/25 22:46:30  cheshire
234 For ease of code searching, renamed ZoneData field of ServiceRecordSet_struct from "nta" to "srs_nta"
235 
236 Revision 1.518  2008/11/25 05:07:15  cheshire
237 <rdar://problem/6374328> Advertise Sleep Proxy metrics in service name
238 
239 Revision 1.517  2008/11/20 01:51:19  cheshire
240 Exported RecreateNATMappings so it's callable from other files
241 
242 Revision 1.516  2008/11/16 16:49:25  cheshire
243 <rdar://problem/6375808> LLQs broken in mDNSResponder-184
244 DNSOpt_LLQData_Space was incorrectly defined to be 18 instead of 22
245 
246 Revision 1.515  2008/11/14 20:59:41  cheshire
247 Added mDNSEthAddressIsZero(A) macro
248 
249 Revision 1.514  2008/11/14 02:17:41  cheshire
250 Added NextScheduledSPS task scheduling variable
251 
252 Revision 1.513  2008/11/14 00:47:19  cheshire
253 Added TimeRcvd and TimeExpire fields to AuthRecord_struct
254 
255 Revision 1.512  2008/11/14 00:00:53  cheshire
256 After client machine wakes up, Sleep Proxy machine need to remove any records
257 it was temporarily holding as proxy for that client
258 
259 Revision 1.511  2008/11/13 19:04:44  cheshire
260 Added definition of OwnerOptData
261 
262 Revision 1.510  2008/11/06 23:48:32  cheshire
263 Changed SleepProxyServerType to mDNSu8
264 
265 Revision 1.509  2008/11/04 23:06:50  cheshire
266 Split RDataBody union definition into RDataBody and RDataBody2, and removed
267 SOA from the normal RDataBody union definition, saving 270 bytes per AuthRecord
268 
269 Revision 1.508  2008/11/04 22:21:43  cheshire
270 Changed zone field of AuthRecord_struct from domainname to pointer, saving 252 bytes per AuthRecord
271 
272 Revision 1.507  2008/11/04 22:13:43  cheshire
273 Made RDataBody parameter to GetRRDisplayString_rdb "const"
274 
275 Revision 1.506  2008/11/04 20:06:19  cheshire
276 <rdar://problem/6186231> Change MAX_DOMAIN_NAME to 256
277 
278 Revision 1.505  2008/11/03 23:49:47  mkrochma
279 Increase NATMAP_DEFAULT_LEASE to 2 hours so we do maintenance wake less often
280 
281 Revision 1.504  2008/10/31 22:55:04  cheshire
282 Initial support for structured SPS names
283 
284 Revision 1.503  2008/10/24 23:58:47  cheshire
285 Ports should be mDNSIPPort, not mDNSOpaque16
286 
287 Revision 1.502  2008/10/23 22:25:56  cheshire
288 Renamed field "id" to more descriptive "updateid"
289 
290 Revision 1.501  2008/10/22 22:22:27  cheshire
291 Added packet structure definitions
292 
293 Revision 1.500  2008/10/22 19:55:35  cheshire
294 Miscellaneous fixes; renamed FindFirstAnswerInCache to FindSPSInCache
295 
296 Revision 1.499  2008/10/22 17:15:47  cheshire
297 Updated definitions of mDNSIPv4AddressIsZero/mDNSIPv4AddressIsOnes, etc.
298 
299 Revision 1.498  2008/10/22 01:01:52  cheshire
300 Added onesEthAddr constant, used for sending ARP broadcasts
301 
302 Revision 1.497  2008/10/21 00:51:11  cheshire
303 Added declaration of mDNSPlatformSetBPF(), used by uds_daemon.c to pass BPF fd to mDNSMacOSX.c
304 
305 Revision 1.496  2008/10/16 22:38:52  cheshire
306 Added declaration of mDNSCoreReceiveRawPacket()
307 
308 Revision 1.495  2008/10/15 22:53:51  cheshire
309 Removed unused "#define LocalReverseMapDomain"
310 
311 Revision 1.494  2008/10/15 20:37:17  cheshire
312 Added "#define DNSOpt_Lease_Space 19"
313 
314 Revision 1.493  2008/10/14 21:37:56  cheshire
315 Removed unnecessary m->BeSleepProxyServer variable
316 
317 Revision 1.492  2008/10/14 20:26:36  cheshire
318 Added definition of a new kDNSType_MAC rdata type
319 
320 Revision 1.491  2008/10/09 22:29:04  cheshire
321 Added "mDNSEthAddr MAC" to NetworkInterfaceInfo_struct
322 
323 Revision 1.490  2008/10/09 21:39:20  cheshire
324 Update list of DNS types
325 
326 Revision 1.489  2008/10/09 18:59:19  cheshire
327 Added NetWakeResolve code, removed unused m->SendDeregistrations and m->SendImmediateAnswers
328 
329 Revision 1.488  2008/10/08 01:02:03  cheshire
330 Added mDNS_SetupQuestion() convenience function
331 
332 Revision 1.487  2008/10/07 21:41:57  mcguire
333 Increase sizecheck limits to account for DNSQuestion added to NetworkInterfaceInfo_struct in 64bit builds
334 
335 Revision 1.486  2008/10/07 15:56:24  cheshire
336 Increase sizecheck limits to account for DNSQuestion added to NetworkInterfaceInfo_struct
337 
338 Revision 1.485  2008/10/04 00:48:37  cheshire
339 Added DNSQuestion to NetworkInterfaceInfo_struct, used for browsing for Sleep Proxy Servers
340 
341 Revision 1.484  2008/10/04 00:01:45  cheshire
342 Move NetworkInterfaceInfo_struct further down in file (we'll need to add a DNSQuestion to it later)
343 
344 Revision 1.483  2008/10/03 23:28:41  cheshire
345 Added declaration of mDNSPlatformSendRawPacket
346 
347 Revision 1.482  2008/10/03 17:30:05  cheshire
348 Added declaration of mDNS_ConfigChanged(mDNS *const m);
349 
350 Revision 1.481  2008/10/02 22:38:58  cheshire
351 Added SleepProxyServer fields, and mDNSCoreBeSleepProxyServer() call for turning SleepProxyServer on and off
352 
353 Revision 1.480  2008/10/01 21:22:17  cheshire
354 Added NetWake field to NetworkInterfaceInfo structure, to signal when Wake-On-Magic-Packet is enabled for that interface
355 
356 Revision 1.479  2008/09/29 20:12:37  cheshire
357 Rename 'AnswerLocalQuestions' to more descriptive 'AnswerLocalOnlyQuestions' and 'AnsweredLocalQ' to 'AnsweredLOQ'
358 
359 Revision 1.478  2008/09/23 02:37:10  cheshire
360 Added FirstLabel/SecondLabel macros
361 
362 Revision 1.477  2008/09/20 00:34:22  mcguire
363 <rdar://problem/6129039> BTMM: Add support for WANPPPConnection
364 
365 Revision 1.476  2008/09/05 22:22:01  cheshire
366 Move "UDPSocket *LocalSocket" field to more logical place in DNSQuestion_struct
367 
368 Revision 1.475  2008/07/25 22:34:11  mcguire
369 fix sizecheck issues for 64bit
370 
371 Revision 1.474  2008/07/24 20:23:03  cheshire
372 <rdar://problem/3988320> Should use randomized source ports and transaction IDs to avoid DNS cache poisoning
373 
374 Revision 1.473  2008/07/18 21:37:42  mcguire
375 <rdar://problem/5736845> BTMM: alternate SSDP queries between multicast & unicast
376 
377 Revision 1.472  2008/07/01 01:39:59  mcguire
378 <rdar://problem/5823010> 64-bit fixes
379 
380 Revision 1.471  2008/06/26 17:24:11  mkrochma
381 <rdar://problem/5450912> BTMM: Stop listening on UDP 5351 for NAT Status Announcements
382 
383 Revision 1.470  2008/06/19 01:20:49  mcguire
384 <rdar://problem/4206534> Use all configured DNS servers
385 
386 Revision 1.469  2008/03/07 18:56:02  cheshire
387 <rdar://problem/5777647> dnsbugtest query every three seconds when source IP address of response doesn't match
388 
389 Revision 1.468  2008/03/06 02:48:34  mcguire
390 <rdar://problem/5321824> write status to the DS
391 
392 Revision 1.467  2008/02/26 20:48:46  cheshire
393 Need parentheses around use of macro argument in mDNS_TimeNow_NoLock(m)
394 
395 Revision 1.466  2008/02/21 21:36:32  cheshire
396 Updated comment about record type values (kDNSRecordTypePacketAns/Auth/Add)
397 
398 Revision 1.465  2008/02/20 00:39:05  mcguire
399 <rdar://problem/5427102> Some device info XML blobs too large
400 
401 Revision 1.464  2008/01/31 23:33:29  mcguire
402 <rdar://problem/5614450> changes to build using gcc 4.2 with -Werror
403 
404 Revision 1.463  2007/12/17 23:53:25  cheshire
405 Added DNSDigest_SignMessageHostByteOrder, for signing messages not yet converted to network byte order
406 
407 Revision 1.462  2007/12/17 23:48:29  cheshire
408 DNSDigest_SignMessage doesn't need to return a result -- it already updates the 'end' parameter
409 
410 Revision 1.461  2007/12/15 00:18:51  cheshire
411 Renamed question->origLease to question->ReqLease
412 
413 Revision 1.460  2007/12/14 23:55:28  cheshire
414 Moved "struct tcpInfo_t" definition from uDNS.c to mDNSEmbeddedAPI.h
415 
416 Revision 1.459  2007/12/07 22:40:34  cheshire
417 Rename 'LocalAnswer' to more descriptive 'AnsweredLocalQ'
418 
419 Revision 1.458  2007/12/07 00:45:58  cheshire
420 <rdar://problem/5526800> BTMM: Need to clean up registrations on shutdown
421 
422 Revision 1.457  2007/12/06 00:22:27  mcguire
423 <rdar://problem/5604567> BTMM: Doesn't work with Linksys WAG300N 1.01.06 (sending from 1026/udp)
424 
425 Revision 1.456  2007/12/05 01:45:35  cheshire
426 Renamed markedForDeletion -> MarkedForDeletion
427 
428 Revision 1.455  2007/12/01 01:21:27  jgraessley
429 <rdar://problem/5623140> mDNSResponder unicast DNS improvements
430 
431 Revision 1.454  2007/12/01 00:34:03  cheshire
432 Fixes from Bob Bradley for building on EFI
433 
434 Revision 1.453  2007/10/29 23:51:22  cheshire
435 Added comment about NATTraversalInfo ExternalAddress field
436 
437 Revision 1.452  2007/10/29 18:13:40  cheshire
438 Added Question_uDNS macro, analogous to AuthRecord_uDNS macro
439 
440 Revision 1.451  2007/10/26 23:42:57  cheshire
441 Removed unused "mDNSs32 expire" field from ServiceRecordSet_struct
442 
443 Revision 1.450  2007/10/26 22:24:08  cheshire
444 Added AuthRecord_uDNS() macro to determine when a given AuthRecord needs to be registered via unicast DNS
445 
446 Revision 1.449  2007/10/25 20:48:47  cheshire
447 For naming consistency (with AuthRecord's UpdateServer) renamed 'ns' to 'SRSUpdateServer'
448 
449 Revision 1.448  2007/10/22 22:19:44  cheshire
450 Tidied up code alignment
451 
452 Revision 1.447  2007/10/22 19:40:30  cheshire
453 <rdar://problem/5519458> BTMM: Machines don't appear in the sidebar on wake from sleep
454 Made subroutine mDNSPlatformSourceAddrForDest(mDNSAddr *const src, const mDNSAddr *const dst)
455 
456 Revision 1.446  2007/10/17 22:49:54  cheshire
457 <rdar://problem/5519458> BTMM: Machines don't appear in the sidebar on wake from sleep
458 
459 Revision 1.445  2007/10/17 22:37:23  cheshire
460 <rdar://problem/5536979> BTMM: Need to create NAT port mapping for receiving LLQ events
461 
462 Revision 1.444  2007/09/29 03:14:52  cheshire
463 <rdar://problem/5513168> BTMM: mDNSResponder memory corruption in GetAuthInfoForName_internal
464 Added AutoTunnelUnregistered macro to check state of DomainAuthInfo AuthRecords
465 
466 Revision 1.443  2007/09/27 21:21:39  cheshire
467 Export CompleteDeregistration so it's callable from other files
468 
469 Revision 1.442  2007/09/27 00:25:39  cheshire
470 Added ttl_seconds parameter to MakeNegativeCacheRecord in preparation for:
471 <rdar://problem/4947392> uDNS: Use SOA to determine TTL for negative answers
472 
473 Revision 1.441  2007/09/26 23:17:49  cheshire
474 Get rid of unused kWideAreaTTL constant
475 
476 Revision 1.440  2007/09/26 22:06:02  cheshire
477 <rdar://problem/5507399> BTMM: No immediate failure notifications for BTMM names
478 
479 Revision 1.439  2007/09/21 21:12:36  cheshire
480 DNSDigest_SignMessage does not need separate "mDNSu16 *numAdditionals" parameter
481 
482 Revision 1.438  2007/09/19 20:32:09  cheshire
483 Export GetAuthInfoForName so it's callable from other files
484 
485 Revision 1.437  2007/09/18 21:42:29  cheshire
486 To reduce programming mistakes, renamed ExtPort to RequestedPort
487 
488 Revision 1.436  2007/09/14 21:26:08  cheshire
489 <rdar://problem/5482627> BTMM: Need to manually avoid port conflicts when using UPnP gateways
490 
491 Revision 1.435  2007/09/13 00:16:41  cheshire
492 <rdar://problem/5468706> Miscellaneous NAT Traversal improvements
493 
494 Revision 1.434  2007/09/12 23:03:07  cheshire
495 <rdar://problem/5476978> DNSServiceNATPortMappingCreate callback not giving correct interface index
496 
497 Revision 1.433  2007/09/12 22:19:28  cheshire
498 <rdar://problem/5476977> Need to listen for port 5350 NAT-PMP announcements
499 
500 Revision 1.432  2007/09/12 19:22:19  cheshire
501 Variable renaming in preparation for upcoming fixes e.g. priv/pub renamed to intport/extport
502 Made NAT Traversal packet handlers take typed data instead of anonymous "mDNSu8 *" byte pointers
503 
504 Revision 1.431  2007/09/11 19:19:16  cheshire
505 Correct capitalization of "uPNP" to "UPnP"
506 
507 Revision 1.430  2007/09/10 22:06:50  cheshire
508 Rename uptime => upseconds and LastNATUptime => LastNATupseconds to make it clear these time values are in seconds
509 
510 Revision 1.429  2007/09/07 21:16:58  cheshire
511 Add new symbol "NATPMPAnnouncementPort" (5350)
512 
513 Revision 1.428  2007/09/05 21:48:01  cheshire
514 <rdar://problem/5385864> BTMM: mDNSResponder flushes wide-area Bonjour records after an hour for a zone.
515 Now that we're respecting the TTL of uDNS records in the cache, the LLQ maintenance code needs
516 to update the cache lifetimes of all relevant records every time it successfully renews an LLQ,
517 otherwise those records will expire and vanish from the cache.
518 
519 Revision 1.427  2007/09/05 20:47:12  cheshire
520 Tidied up alignment of code layout
521 
522 Revision 1.426  2007/09/04 20:37:06  cheshire
523 <rdar://problem/5457287> mDNSResponder taking up 100% CPU in ReissueBlockedQuestions
524 Reorder fields into more logical order, with AuthInfo before DuplicateOf
525 
526 Revision 1.425  2007/08/31 19:53:14  cheshire
527 <rdar://problem/5431151> BTMM: IPv6 address lookup should not succeed if autotunnel cannot be setup
528 If AutoTunnel setup fails, the code now generates a fake NXDomain error saying that the requested AAAA record does not exist
529 
530 Revision 1.424  2007/08/31 18:49:49  vazquez
531 <rdar://problem/5393719> BTMM: Need to properly deregister when stopping BTMM
532 
533 Revision 1.423  2007/08/31 00:04:28  cheshire
534 Added comment explaining deltime in DomainAuthInfo structure
535 
536 Revision 1.422  2007/08/28 23:58:42  cheshire
537 Rename HostTarget -> AutoTarget
538 
539 Revision 1.421  2007/08/27 20:30:43  cheshire
540 Only include TunnelClients list when building for OS X
541 
542 Revision 1.420  2007/08/23 21:47:09  vazquez
543 <rdar://problem/5427316> BTMM: mDNSResponder sends NAT-PMP packets on public network
544 make sure we clean up port mappings on base stations by sending a lease value of 0,
545 and only send NAT-PMP packets on private networks; also save some memory by
546 not using packet structs in NATTraversals.
547 
548 Revision 1.419  2007/08/08 21:07:47  vazquez
549 <rdar://problem/5244687> BTMM: Need to advertise model information via wide-area bonjour
550 
551 Revision 1.418  2007/08/01 16:09:13  cheshire
552 Removed unused NATTraversalInfo substructure from AuthRecord; reduced structure sizecheck values accordingly
553 
554 Revision 1.417  2007/08/01 03:04:59  cheshire
555 Add NATTraversalInfo structures to HostnameInfo and DomainAuthInfo
556 
557 Revision 1.416  2007/08/01 00:04:13  cheshire
558 <rdar://problem/5261696> Crash in tcpKQSocketCallback
559 Half-open TCP connections were not being cancelled properly
560 
561 Revision 1.415  2007/07/31 02:28:35  vazquez
562 <rdar://problem/3734269> NAT-PMP: Detect public IP address changes and base station reboot
563 
564 Revision 1.414  2007/07/30 23:34:19  cheshire
565 Remove unused "udpSock" from DNSQuestion
566 
567 Revision 1.413  2007/07/28 01:25:56  cheshire
568 <rdar://problem/4780038> BTMM: Add explicit UDP event port to LLQ setup request, to fix LLQs not working behind NAT
569 
570 Revision 1.412  2007/07/27 23:57:23  cheshire
571 Added compile-time structure size checks
572 
573 Revision 1.411  2007/07/27 22:50:08  vazquez
574 Allocate memory for UPnP request and reply buffers instead of using arrays
575 
576 Revision 1.410  2007/07/27 19:37:19  cheshire
577 Moved AutomaticBrowseDomainQ into main mDNS object
578 
579 Revision 1.409  2007/07/27 19:30:39  cheshire
580 Changed mDNSQuestionCallback parameter from mDNSBool to QC_result,
581 to properly reflect tri-state nature of the possible responses
582 
583 Revision 1.408  2007/07/27 18:44:01  cheshire
584 Rename "AnswerQuestionWithResourceRecord" to more informative "AnswerCurrentQuestionWithResourceRecord"
585 
586 Revision 1.407  2007/07/26 21:19:26  vazquez
587 Retry port mapping with incremented port number (up to max) in order to handle
588 port mapping conflicts on UPnP gateways
589 
590 Revision 1.406  2007/07/25 22:19:59  cheshire
591 ClientTunnel structure also needs a rmt_outer_port field
592 
593 Revision 1.405  2007/07/25 03:05:02  vazquez
594 Fixes for:
595 <rdar://problem/5338913> LegacyNATTraversal: UPnP heap overflow
596 <rdar://problem/5338933> LegacyNATTraversal: UPnP stack buffer overflow
597 and a myriad of other security problems
598 
599 Revision 1.404  2007/07/24 20:22:07  cheshire
600 Add AutoTunnelHostAddrActive flag
601 
602 Revision 1.403  2007/07/24 04:14:29  cheshire
603 <rdar://problem/5356281> LLQs not working in with NAT Traversal
604 
605 Revision 1.402  2007/07/21 00:54:44  cheshire
606 <rdar://problem/5344576> Delay IPv6 address callback until AutoTunnel route and policy is configured
607 
608 Revision 1.401  2007/07/20 20:01:38  cheshire
609 Rename "mDNS_DomainTypeBrowseLegacy" as "mDNS_DomainTypeBrowseAutomatic"
610 
611 Revision 1.400  2007/07/20 00:54:18  cheshire
612 <rdar://problem/4641118> Need separate SCPreferences for per-user .Mac settings
613 
614 Revision 1.399  2007/07/18 03:22:35  cheshire
615 SetupLocalAutoTunnelInterface_internal needs to be callable from uDNS.c
616 
617 Revision 1.398  2007/07/18 02:26:56  cheshire
618 Don't need to declare UpdateTunnels here
619 
620 Revision 1.397  2007/07/18 01:03:50  cheshire
621 <rdar://problem/5303834> Automatically configure IPSec policy when resolving services
622 Add list of client tunnels so we can automatically reconfigure when local address changes
623 
624 Revision 1.396  2007/07/16 23:54:48  cheshire
625 <rdar://problem/5338850> Crash when removing or changing DNS keys
626 
627 Revision 1.395  2007/07/16 20:12:33  vazquez
628 <rdar://problem/3867231> LegacyNATTraversal: Need complete rewrite
629 
630 Revision 1.394  2007/07/12 02:51:27  cheshire
631 <rdar://problem/5303834> Automatically configure IPSec policy when resolving services
632 
633 Revision 1.393  2007/07/11 23:43:42  cheshire
634 Rename PurgeCacheResourceRecord to mDNS_PurgeCacheResourceRecord
635 
636 Revision 1.392  2007/07/11 22:44:40  cheshire
637 <rdar://problem/5328801> SIGHUP should purge the cache
638 
639 Revision 1.391  2007/07/11 20:30:45  cheshire
640 <rdar://problem/5304766> Register IPSec tunnel with IPv4-only hostname and create NAT port mappings
641 Added AutoTunnelTarget and AutoTunnelService to DomainAuthInfo structure
642 
643 Revision 1.390  2007/07/11 18:56:55  cheshire
644 Added comments about AutoTunnelHostAddr and AutoTunnelLabel
645 
646 Revision 1.389  2007/07/11 02:44:03  cheshire
647 <rdar://problem/5303807> Register IPv6-only hostname and don't create port mappings for AutoTunnel services
648 Added AutoTunnel fields to structures
649 
650 Revision 1.388  2007/07/10 01:53:18  cheshire
651 <rdar://problem/5196524> uDNS: mDNSresponder is leaking TCP connections to DNS server
652 AuthRecord, ServiceRecordSet, and DNSQuestion structures need tcpInfo_t pointers
653 so they can keep track of what TCP connections they open
654 
655 Revision 1.387  2007/07/06 18:55:15  cheshire
656 Add explicit NextScheduledNATOp scheduling variable
657 
658 Revision 1.386  2007/07/03 20:54:11  cheshire
659 Tidied up code layout of NATTraversalInfo_struct fields and comments
660 
661 Revision 1.385  2007/07/03 00:40:23  vazquez
662 More changes for <rdar://problem/5301908> Clean up NAT state machine (necessary for 6 other fixes)
663 Safely deal with packet replies and client callbacks
664 
665 Revision 1.384  2007/06/29 00:08:07  vazquez
666 <rdar://problem/5301908> Clean up NAT state machine (necessary for 6 other fixes)
667 
668 Revision 1.383  2007/06/20 01:10:12  cheshire
669 <rdar://problem/5280520> Sync iPhone changes into main mDNSResponder code
670 
671 Revision 1.382  2007/06/19 20:31:59  cheshire
672 Add DNSServer_Disabled state
673 Add mDNSInterfaceID for DNS servers reachable over specific interfaces
674 
675 Revision 1.381  2007/06/15 18:11:16  cheshire
676 <rdar://problem/5174466> mDNSResponder crashed in memove() near end of MobileSafari stress test
677 Made AssignDomainName more defensive when source name is garbage
678 
679 Revision 1.380  2007/05/25 00:04:51  cheshire
680 Added comment explaining rdlength
681 
682 Revision 1.379  2007/05/21 18:04:40  cheshire
683 Updated comments -- port_mapping_create_reply renamed to port_mapping_reply
684 
685 Revision 1.378  2007/05/17 19:11:46  cheshire
686 Tidy up code layout
687 
688 Revision 1.377  2007/05/15 00:43:33  cheshire
689 Remove unused regState_Cancelled
690 
691 Revision 1.376  2007/05/14 23:51:49  cheshire
692 Added constants MAX_REVERSE_MAPPING_NAME_V4 and MAX_REVERSE_MAPPING_NAME_V6
693 
694 Revision 1.375  2007/05/10 21:19:18  cheshire
695 Rate-limit DNS test queries to at most one per three seconds
696 (useful when we have a dozen active WAB queries, and then we join a new network)
697 
698 Revision 1.374  2007/05/07 22:07:47  cheshire
699 <rdar://problem/4738025> Enhance GetLargeResourceRecord to decompress more record types
700 
701 Revision 1.373  2007/05/07 20:43:45  cheshire
702 <rdar://problem/4241419> Reduce the number of queries and announcements
703 
704 Revision 1.372  2007/05/04 22:15:29  cheshire
705 Get rid of unused q->RestartTime
706 
707 Revision 1.371  2007/05/03 22:40:37  cheshire
708 <rdar://problem/4669229> mDNSResponder ignores bogus null target in SRV record
709 
710 Revision 1.370  2007/05/02 22:18:09  cheshire
711 Renamed NATTraversalInfo_struct context to NATTraversalContext
712 
713 Revision 1.369  2007/05/01 21:21:42  cheshire
714 Add missing parentheses in LEASE_OPT_RDLEN definition
715 
716 Revision 1.368  2007/04/30 21:33:38  cheshire
717 Fix crash when a callback unregisters a service while the UpdateSRVRecords() loop
718 is iterating through the m->ServiceRegistrations list
719 
720 Revision 1.367  2007/04/28 01:31:59  cheshire
721 Improve debugging support for catching memory corruption problems
722 
723 Revision 1.366  2007/04/27 19:28:02  cheshire
724 Any code that calls StartGetZoneData needs to keep a handle to the structure, so
725 it can cancel it if necessary. (First noticed as a crash in Apple Remote Desktop
726 -- it would start a query and then quickly cancel it, and then when
727 StartGetZoneData completed, it had a dangling pointer and crashed.)
728 
729 Revision 1.365  2007/04/26 00:35:15  cheshire
730 <rdar://problem/5140339> uDNS: Domain discovery not working over VPN
731 Fixes to make sure results update correctly when connectivity changes (e.g. a DNS server
732 inside the firewall may give answers where a public one gives none, and vice versa.)
733 
734 Revision 1.364  2007/04/24 02:07:42  cheshire
735 <rdar://problem/4246187> Identical client queries should reference a single shared core query
736 Deleted some more redundant code
737 
738 Revision 1.363  2007/04/24 00:09:47  cheshire
739 Remove MappedV4 field from mDNS_struct (not actually used anywhere)
740 
741 Revision 1.362  2007/04/22 06:02:02  cheshire
742 <rdar://problem/4615977> Query should immediately return failure when no server
743 
744 Revision 1.361  2007/04/21 19:43:33  cheshire
745 Code tidying: represent NAT opcodes as bitwise combinations rather than numerical additions
746 
747 Revision 1.360  2007/04/20 21:17:24  cheshire
748 For naming consistency, kDNSRecordTypeNegative should be kDNSRecordTypePacketNegative
749 
750 Revision 1.359  2007/04/19 22:50:53  cheshire
751 <rdar://problem/4246187> Identical client queries should reference a single shared core query
752 
753 Revision 1.358  2007/04/19 20:06:41  cheshire
754 Rename field 'Private' (sounds like a boolean) to more informative 'AuthInfo' (it's a DomainAuthInfo pointer)
755 
756 Revision 1.357  2007/04/19 18:14:51  cheshire
757 In mDNS_AddSearchDomain_CString check for NULL pointer before calling MakeDomainNameFromDNSNameString()
758 
759 Revision 1.356  2007/04/18 20:56:46  cheshire
760 Added mDNS_AddSearchDomain_CString macro
761 
762 Revision 1.355  2007/04/17 19:21:29  cheshire
763 <rdar://problem/5140339> Domain discovery not working over VPN
764 
765 Revision 1.354  2007/04/05 22:55:34  cheshire
766 <rdar://problem/5077076> Records are ending up in Lighthouse without expiry information
767 
768 Revision 1.353  2007/04/05 20:40:37  cheshire
769 Remove unused mDNSPlatformTCPGetFlags()
770 
771 Revision 1.352  2007/04/04 21:48:52  cheshire
772 <rdar://problem/4720694> Combine unicast authoritative answer list with multicast list
773 
774 Revision 1.351  2007/04/04 01:27:45  cheshire
775 Update comment
776 
777 Revision 1.350  2007/04/04 00:03:26  cheshire
778 <rdar://problem/5089862> DNSServiceQueryRecord is returning kDNSServiceErr_NoSuchRecord for empty rdata
779 
780 Revision 1.349  2007/04/03 19:37:58  cheshire
781 Rename mDNSAddrIsv4Private() to more precise mDNSAddrIsRFC1918()
782 
783 Revision 1.348  2007/04/03 19:13:39  cheshire
784 Added macros mDNSSameIPPort, mDNSSameOpaque16, mDNSIPPortIsZero, mDNSOpaque16IsZero
785 
786 Revision 1.347  2007/03/28 20:59:26  cheshire
787 <rdar://problem/4743285> Remove inappropriate use of IsPrivateV4Addr()
788 
789 Revision 1.346  2007/03/28 15:56:37  cheshire
790 <rdar://problem/5085774> Add listing of NAT port mapping and GetAddrInfo requests in SIGINFO output
791 
792 Revision 1.345  2007/03/22 19:29:23  cheshire
793 Add comment and check to ensure StandardAuthRDSize is at least 256 bytes
794 
795 Revision 1.344  2007/03/22 18:31:48  cheshire
796 Put dst parameter first in mDNSPlatformStrCopy/mDNSPlatformMemCopy, like conventional Posix strcpy/memcpy
797 
798 Revision 1.343  2007/03/22 00:49:20  cheshire
799 <rdar://problem/4848295> Advertise model information via Bonjour
800 
801 Revision 1.342  2007/03/21 23:06:00  cheshire
802 Rename uDNS_HostnameInfo to HostnameInfo; deleted some unused fields
803 
804 Revision 1.341  2007/03/21 20:44:11  cheshire
805 Added mDNSAddressIsv4LinkLocal macro
806 
807 Revision 1.340  2007/03/21 00:30:02  cheshire
808 <rdar://problem/4789455> Multiple errors in DNameList-related code
809 
810 Revision 1.339  2007/03/20 17:07:15  cheshire
811 Rename "struct uDNS_TCPSocket_struct" to "TCPSocket", "struct uDNS_UDPSocket_struct" to "UDPSocket"
812 
813 Revision 1.338  2007/03/10 02:28:28  cheshire
814 Added comment explaining NATResponseHndlr
815 
816 Revision 1.337  2007/03/10 02:02:58  cheshire
817 <rdar://problem/4961667> uDNS: LLQ refresh response packet causes cached records to be removed from cache
818 Eliminate unnecessary "InternalResponseHndlr responseCallback" function pointer
819 
820 Revision 1.336  2007/02/28 22:12:24  cheshire
821 Get rid of unused mDNSVal32 and mDNSOpaque32fromIntVal
822 
823 Revision 1.335  2007/02/28 21:49:07  cheshire
824 Off-by-one error: SameDomainLabelCS (case-sensitive) was stopping one character short of
825 the end of the label, e.g. it would fail to detect that "chesh1" and "chesh2" are different.
826 
827 Revision 1.334  2007/02/28 01:44:26  cheshire
828 <rdar://problem/5027863> Byte order bugs in uDNS.c, uds_daemon.c, dnssd_clientstub.c
829 
830 Revision 1.333  2007/02/27 22:55:22  cheshire
831 Get rid of unused AllDNSLinkGroupv4 and AllDNSLinkGroupv6
832 
833 Revision 1.332  2007/02/27 02:48:24  cheshire
834 Parameter to LNT_GetPublicIP function is IPv4 address, not anonymous "mDNSOpaque32" object
835 
836 Revision 1.331  2007/02/14 03:16:39  cheshire
837 <rdar://problem/4789477> Eliminate unnecessary malloc/free in mDNSCore code
838 
839 Revision 1.330  2007/02/08 21:12:28  cheshire
840 <rdar://problem/4386497> Stop reading /etc/mDNSResponder.conf on every sleep/wake
841 
842 Revision 1.329  2007/02/07 01:19:36  cheshire
843 <rdar://problem/4849427> API: Reconcile conflicting error code values
844 
845 Revision 1.328  2007/01/25 00:19:40  cheshire
846 Add CNAMEReferrals field to DNSQuestion_struct
847 
848 Revision 1.327  2007/01/23 02:56:10  cheshire
849 Store negative results in the cache, instead of generating them out of pktResponseHndlr()
850 
851 Revision 1.326  2007/01/20 01:30:49  cheshire
852 Update comments
853 
854 Revision 1.325  2007/01/19 18:39:11  cheshire
855 Fix a bunch of parameters that should have been declared "const"
856 
857 Revision 1.324  2007/01/19 18:04:04  cheshire
858 For naming consistency, use capital letters for RR types: rdataOpt should be rdataOPT
859 
860 Revision 1.323  2007/01/17 21:46:02  cheshire
861 Remove redundant duplicated "isPrivate" field from LLQ_Info
862 
863 Revision 1.322  2007/01/10 22:51:56  cheshire
864 <rdar://problem/4917539> Add support for one-shot private queries as well as long-lived private queries
865 
866 Revision 1.321  2007/01/09 22:37:18  cheshire
867 Provide ten-second grace period for deleted keys, to give mDNSResponder
868 time to delete host name before it gives up access to the required key.
869 
870 Revision 1.320  2007/01/05 08:30:41  cheshire
871 Trim excessive "Log" checkin history from before 2006
872 (checkin history still available via "cvs log ..." of course)
873 
874 Revision 1.319  2007/01/04 23:11:11  cheshire
875 <rdar://problem/4720673> uDNS: Need to start caching unicast records
876 When an automatic browsing domain is removed, generate appropriate "remove" events for legacy queries
877 
878 Revision 1.318  2007/01/04 20:57:48  cheshire
879 Rename ReturnCNAME to ReturnIntermed (for ReturnIntermediates)
880 
881 Revision 1.317  2007/01/04 02:39:53  cheshire
882 <rdar://problem/4030599> Hostname passed into DNSServiceRegister ignored for Wide-Area service registrations
883 
884 Revision 1.316  2006/12/22 20:59:49  cheshire
885 <rdar://problem/4742742> Read *all* DNS keys from keychain,
886  not just key for the system-wide default registration domain
887 
888 Revision 1.315  2006/12/20 04:07:35  cheshire
889 Remove uDNS_info substructure from AuthRecord_struct
890 
891 Revision 1.314  2006/12/19 22:49:23  cheshire
892 Remove uDNS_info substructure from ServiceRecordSet_struct
893 
894 Revision 1.313  2006/12/19 02:38:20  cheshire
895 Get rid of unnecessary duplicate query ID field from DNSQuestion_struct
896 
897 Revision 1.312  2006/12/19 02:18:48  cheshire
898 Get rid of unnecessary duplicate "void *context" field from DNSQuestion_struct
899 
900 Revision 1.311  2006/12/16 01:58:31  cheshire
901 <rdar://problem/4720673> uDNS: Need to start caching unicast records
902 
903 Revision 1.310  2006/12/15 19:09:56  cheshire
904 <rdar://problem/4769083> ValidateRData() should be stricter about malformed MX and SRV records
905 Made DomainNameLength() more defensive by adding a limit parameter, so it can be
906 safely used to inspect potentially malformed data received from external sources.
907 Without this, a domain name that starts off apparently valid, but extends beyond the end of
908 the received packet data, could have appeared valid if the random bytes are already in memory
909 beyond the end of the packet just happened to have reasonable values (e.g. all zeroes).
910 
911 Revision 1.309  2006/12/14 03:02:37  cheshire
912 <rdar://problem/4838433> Tools: dns-sd -G 0 only returns IPv6 when you have a routable IPv6 address
913 
914 Revision 1.308  2006/11/30 23:07:56  herscher
915 <rdar://problem/4765644> uDNS: Sync up with Lighthouse changes for Private DNS
916 
917 Revision 1.307  2006/11/18 05:01:30  cheshire
918 Preliminary support for unifying the uDNS and mDNS code,
919 including caching of uDNS answers
920 
921 Revision 1.306  2006/11/10 07:44:04  herscher
922 <rdar://problem/4825493> Fix Daemon locking failures while toggling BTMM
923 
924 Revision 1.305  2006/11/10 00:54:15  cheshire
925 <rdar://problem/4816598> Changing case of Computer Name doesn't work
926 
927 Revision 1.304  2006/10/20 05:35:05  herscher
928 <rdar://problem/4720713> uDNS: Merge unicast active question list with multicast list.
929 
930 Revision 1.303  2006/10/04 21:37:33  herscher
931 Remove uDNS_info substructure from DNSQuestion_struct
932 
933 Revision 1.302  2006/09/26 01:53:25  herscher
934 <rdar://problem/4245016> NAT Port Mapping API (for both NAT-PMP and UPnP Gateway Protocol)
935 
936 Revision 1.301  2006/09/15 21:20:15  cheshire
937 Remove uDNS_info substructure from mDNS_struct
938 
939 Revision 1.300  2006/08/14 23:24:23  cheshire
940 Re-licensed mDNSResponder daemon source code under Apache License, Version 2.0
941 
942 Revision 1.299  2006/07/15 02:01:28  cheshire
943 <rdar://problem/4472014> Add Private DNS client functionality to mDNSResponder
944 Fix broken "empty string" browsing
945 
946 Revision 1.298  2006/07/05 22:55:03  cheshire
947 <rdar://problem/4472014> Add Private DNS client functionality to mDNSResponder
948 Need Private field in uDNS_RegInfo
949 
950 Revision 1.297  2006/07/05 22:20:03  cheshire
951 <rdar://problem/4472014> Add Private DNS client functionality to mDNSResponder
952 
953 Revision 1.296  2006/06/29 05:28:01  cheshire
954 Added comment about mDNSlocal and mDNSexport
955 
956 Revision 1.295  2006/06/29 03:02:43  cheshire
957 <rdar://problem/4607042> mDNSResponder NXDOMAIN and CNAME support
958 
959 Revision 1.294  2006/06/28 06:50:08  cheshire
960 In future we may want to change definition of mDNSs32 from "signed long" to "signed int"
961 I doubt anyone is building mDNSResponder on systems where int is 16-bits,
962 but lets add a compile-time assertion to make sure.
963 
964 Revision 1.293  2006/06/12 18:00:43  cheshire
965 To make code a little more defensive, check _ILP64 before _LP64,
966 in case both are set by mistake on some platforms
967 
968 Revision 1.292  2006/03/19 17:00:57  cheshire
969 Define symbol MaxMsg instead of using hard-coded constant value '80'
970 
971 Revision 1.291  2006/03/19 02:00:07  cheshire
972 <rdar://problem/4073825> Improve logic for delaying packets after repeated interface transitions
973 
974 Revision 1.290  2006/03/08 22:42:23  cheshire
975 Fix spelling mistake: LocalReverseMapomain -> LocalReverseMapDomain
976 
977 Revision 1.289  2006/02/26 00:54:41  cheshire
978 Fixes to avoid code generation warning/error on FreeBSD 7
979 
980 */
981 
982 #ifndef __mDNSClientAPI_h
983 #define __mDNSClientAPI_h
984 
985 #if defined(EFI32) || defined(EFI64) || defined(EFIX64)
986 // EFI doesn't have stdarg.h unless it's building with GCC.
987 #include "Tiano.h"
988 #if !defined(__GNUC__)
989 #define va_list         VA_LIST
990 #define va_start(a, b)  VA_START(a, b)
991 #define va_end(a)       VA_END(a)
992 #define va_arg(a, b)    VA_ARG(a, b)
993 #endif
994 #else
995 #include <stdarg.h>		// stdarg.h is required for for va_list support for the mDNS_vsnprintf declaration
996 #endif
997 
998 #include "mDNSDebug.h"
999 #if APPLE_OSX_mDNSResponder
1000 #include <uuid/uuid.h>
1001 #endif
1002 
1003 #ifdef __cplusplus
1004 	extern "C" {
1005 #endif
1006 
1007 // ***************************************************************************
1008 // Function scope indicators
1009 
1010 // If you see "mDNSlocal" before a function name in a C file, it means the function is not callable outside this file
1011 #ifndef mDNSlocal
1012 #define mDNSlocal static
1013 #endif
1014 // If you see "mDNSexport" before a symbol in a C file, it means the symbol is exported for use by clients
1015 // For every "mDNSexport" in a C file, there needs to be a corresponding "extern" declaration in some header file
1016 // (When a C file #includes a header file, the "extern" declarations tell the compiler:
1017 // "This symbol exists -- but not necessarily in this C file.")
1018 #ifndef mDNSexport
1019 #define mDNSexport
1020 #endif
1021 
1022 // Explanation: These local/export markers are a little habit of mine for signaling the programmers' intentions.
1023 // When "mDNSlocal" is just a synonym for "static", and "mDNSexport" is a complete no-op, you could be
1024 // forgiven for asking what purpose they serve. The idea is that if you see "mDNSexport" in front of a
1025 // function definition it means the programmer intended it to be exported and callable from other files
1026 // in the project. If you see "mDNSlocal" in front of a function definition it means the programmer
1027 // intended it to be private to that file. If you see neither in front of a function definition it
1028 // means the programmer forgot (so you should work out which it is supposed to be, and fix it).
1029 // Using "mDNSlocal" instead of "static" makes it easier to do a textual searches for one or the other.
1030 // For example you can do a search for "static" to find if any functions declare any local variables as "static"
1031 // (generally a bad idea unless it's also "const", because static storage usually risks being non-thread-safe)
1032 // without the results being cluttered with hundreds of matches for functions declared static.
1033 // - Stuart Cheshire
1034 
1035 // ***************************************************************************
1036 // Structure packing macro
1037 
1038 // If we're not using GNUC, it's not fatal.
1039 // Most compilers naturally pack the on-the-wire structures correctly anyway, so a plain "struct" is usually fine.
1040 // In the event that structures are not packed correctly, mDNS_Init() will detect this and report an error, so the
1041 // developer will know what's wrong, and can investigate what needs to be done on that compiler to provide proper packing.
1042 #ifndef packedstruct
1043  #ifdef __packed
1044   #define packedstruct struct __packed
1045   #define packedunion  union __packed
1046  #elif ((__GNUC__ > 2) || ((__GNUC__ == 2) && (__GNUC_MINOR__ >= 9)))
1047   #define packedstruct struct __attribute__((__packed__))
1048   #define packedunion  union  __attribute__((__packed__))
1049  #else
1050   #define packedstruct struct
1051   #define packedunion  union
1052  #endif
1053 #endif
1054 
1055 // ***************************************************************************
1056 #if 0
1057 #pragma mark - DNS Resource Record class and type constants
1058 #endif
1059 
1060 typedef enum							// From RFC 1035
1061 	{
1062 	kDNSClass_IN               = 1,		// Internet
1063 	kDNSClass_CS               = 2,		// CSNET
1064 	kDNSClass_CH               = 3,		// CHAOS
1065 	kDNSClass_HS               = 4,		// Hesiod
1066 	kDNSClass_NONE             = 254,	// Used in DNS UPDATE [RFC 2136]
1067 
1068 	kDNSClass_Mask             = 0x7FFF,// Multicast DNS uses the bottom 15 bits to identify the record class...
1069 	kDNSClass_UniqueRRSet      = 0x8000,// ... and the top bit indicates that all other cached records are now invalid
1070 
1071 	kDNSQClass_ANY             = 255,	// Not a DNS class, but a DNS query class, meaning "all classes"
1072 	kDNSQClass_UnicastResponse = 0x8000	// Top bit set in a question means "unicast response acceptable"
1073 	} DNS_ClassValues;
1074 
1075 typedef enum				// From RFC 1035
1076 	{
1077 	kDNSType_A = 1,			//  1 Address
1078 	kDNSType_NS,			//  2 Name Server
1079 	kDNSType_MD,			//  3 Mail Destination
1080 	kDNSType_MF,			//  4 Mail Forwarder
1081 	kDNSType_CNAME,			//  5 Canonical Name
1082 	kDNSType_SOA,			//  6 Start of Authority
1083 	kDNSType_MB,			//  7 Mailbox
1084 	kDNSType_MG,			//  8 Mail Group
1085 	kDNSType_MR,			//  9 Mail Rename
1086 	kDNSType_NULL,			// 10 NULL RR
1087 	kDNSType_WKS,			// 11 Well-known-service
1088 	kDNSType_PTR,			// 12 Domain name pointer
1089 	kDNSType_HINFO,			// 13 Host information
1090 	kDNSType_MINFO,			// 14 Mailbox information
1091 	kDNSType_MX,			// 15 Mail Exchanger
1092 	kDNSType_TXT,			// 16 Arbitrary text string
1093 	kDNSType_RP,			// 17 Responsible person
1094 	kDNSType_AFSDB,			// 18 AFS cell database
1095 	kDNSType_X25,			// 19 X_25 calling address
1096 	kDNSType_ISDN,			// 20 ISDN calling address
1097 	kDNSType_RT,			// 21 Router
1098 	kDNSType_NSAP,			// 22 NSAP address
1099 	kDNSType_NSAP_PTR,		// 23 Reverse NSAP lookup (deprecated)
1100 	kDNSType_SIG,			// 24 Security signature
1101 	kDNSType_KEY,			// 25 Security key
1102 	kDNSType_PX,			// 26 X.400 mail mapping
1103 	kDNSType_GPOS,			// 27 Geographical position (withdrawn)
1104 	kDNSType_AAAA,			// 28 IPv6 Address
1105 	kDNSType_LOC,			// 29 Location Information
1106 	kDNSType_NXT,			// 30 Next domain (security)
1107 	kDNSType_EID,			// 31 Endpoint identifier
1108 	kDNSType_NIMLOC,		// 32 Nimrod Locator
1109 	kDNSType_SRV,			// 33 Service record
1110 	kDNSType_ATMA,			// 34 ATM Address
1111 	kDNSType_NAPTR,			// 35 Naming Authority PoinTeR
1112 	kDNSType_KX,			// 36 Key Exchange
1113 	kDNSType_CERT,			// 37 Certification record
1114 	kDNSType_A6,			// 38 IPv6 Address (deprecated)
1115 	kDNSType_DNAME,			// 39 Non-terminal DNAME (for IPv6)
1116 	kDNSType_SINK,			// 40 Kitchen sink (experimental)
1117 	kDNSType_OPT,			// 41 EDNS0 option (meta-RR)
1118 	kDNSType_APL,			// 42 Address Prefix List
1119 	kDNSType_DS,			// 43 Delegation Signer
1120 	kDNSType_SSHFP,			// 44 SSH Key Fingerprint
1121 	kDNSType_IPSECKEY,		// 45 IPSECKEY
1122 	kDNSType_RRSIG,			// 46 RRSIG
1123 	kDNSType_NSEC,			// 47 Denial of Existence
1124 	kDNSType_DNSKEY,		// 48 DNSKEY
1125 	kDNSType_DHCID,			// 49 DHCP Client Identifier
1126 	kDNSType_NSEC3,			// 50 Hashed Authenticated Denial of Existence
1127 	kDNSType_NSEC3PARAM,	// 51 Hashed Authenticated Denial of Existence
1128 
1129 	kDNSType_HIP = 55,		// 55 Host Identity Protocol
1130 
1131 	kDNSType_SPF = 99,		// 99 Sender Policy Framework for E-Mail
1132 	kDNSType_UINFO,			// 100 IANA-Reserved
1133 	kDNSType_UID,			// 101 IANA-Reserved
1134 	kDNSType_GID,			// 102 IANA-Reserved
1135 	kDNSType_UNSPEC,		// 103 IANA-Reserved
1136 
1137 	kDNSType_TKEY = 249,	// 249 Transaction key
1138 	kDNSType_TSIG,			// 250 Transaction signature
1139 	kDNSType_IXFR,			// 251 Incremental zone transfer
1140 	kDNSType_AXFR,			// 252 Transfer zone of authority
1141 	kDNSType_MAILB,			// 253 Transfer mailbox records
1142 	kDNSType_MAILA,			// 254 Transfer mail agent records
1143 	kDNSQType_ANY			// Not a DNS type, but a DNS query type, meaning "all types"
1144 	} DNS_TypeValues;
1145 
1146 // ***************************************************************************
1147 #if 0
1148 #pragma mark -
1149 #pragma mark - Simple types
1150 #endif
1151 
1152 // mDNS defines its own names for these common types to simplify portability across
1153 // multiple platforms that may each have their own (different) names for these types.
1154 typedef          int   mDNSBool;
1155 typedef   signed char  mDNSs8;
1156 typedef unsigned char  mDNSu8;
1157 typedef   signed short mDNSs16;
1158 typedef unsigned short mDNSu16;
1159 
1160 // <http://gcc.gnu.org/onlinedocs/gcc-3.3.3/cpp/Common-Predefined-Macros.html> says
1161 //   __LP64__ _LP64
1162 //   These macros are defined, with value 1, if (and only if) the compilation is
1163 //   for a target where long int and pointer both use 64-bits and int uses 32-bit.
1164 // <http://www.intel.com/software/products/compilers/clin/docs/ug/lin1077.htm> says
1165 //   Macro Name __LP64__ Value 1
1166 // A quick Google search for "defined(__LP64__)" OR "#ifdef __LP64__" gives 2590 hits and
1167 // a search for "#if __LP64__" gives only 12, so I think we'll go with the majority and use defined()
1168 #if defined(_ILP64) || defined(__ILP64__)
1169 typedef   signed int32 mDNSs32;
1170 typedef unsigned int32 mDNSu32;
1171 #elif defined(_LP64) || defined(__LP64__)
1172 typedef   signed int   mDNSs32;
1173 typedef unsigned int   mDNSu32;
1174 #else
1175 typedef   signed long  mDNSs32;
1176 typedef unsigned long  mDNSu32;
1177 //typedef   signed int mDNSs32;
1178 //typedef unsigned int mDNSu32;
1179 #endif
1180 
1181 // To enforce useful type checking, we make mDNSInterfaceID be a pointer to a dummy struct
1182 // This way, mDNSInterfaceIDs can be assigned, and compared with each other, but not with other types
1183 // Declaring the type to be the typical generic "void *" would lack this type checking
1184 typedef struct mDNSInterfaceID_dummystruct { void *dummy; } *mDNSInterfaceID;
1185 
1186 // These types are for opaque two- and four-byte identifiers.
1187 // The "NotAnInteger" fields of the unions allow the value to be conveniently passed around in a
1188 // register for the sake of efficiency, and compared for equality or inequality, but don't forget --
1189 // just because it is in a register doesn't mean it is an integer. Operations like greater than,
1190 // less than, add, multiply, increment, decrement, etc., are undefined for opaque identifiers,
1191 // and if you make the mistake of trying to do those using the NotAnInteger field, then you'll
1192 // find you get code that doesn't work consistently on big-endian and little-endian machines.
1193 #if defined(_WIN32)
1194  #pragma pack(push,2)
1195 #endif
1196 typedef       union { mDNSu8 b[ 2]; mDNSu16 NotAnInteger; } mDNSOpaque16;
1197 typedef       union { mDNSu8 b[ 4]; mDNSu32 NotAnInteger; } mDNSOpaque32;
1198 typedef packedunion { mDNSu8 b[ 6]; mDNSu16 w[3]; mDNSu32 l[1]; } mDNSOpaque48;
1199 typedef       union { mDNSu8 b[ 8]; mDNSu16 w[4]; mDNSu32 l[2]; } mDNSOpaque64;
1200 typedef       union { mDNSu8 b[16]; mDNSu16 w[8]; mDNSu32 l[4]; } mDNSOpaque128;
1201 #if defined(_WIN32)
1202  #pragma pack(pop)
1203 #endif
1204 
1205 typedef mDNSOpaque16  mDNSIPPort;		// An IP port is a two-byte opaque identifier (not an integer)
1206 typedef mDNSOpaque32  mDNSv4Addr;		// An IP address is a four-byte opaque identifier (not an integer)
1207 typedef mDNSOpaque128 mDNSv6Addr;		// An IPv6 address is a 16-byte opaque identifier (not an integer)
1208 typedef mDNSOpaque48  mDNSEthAddr;		// An Ethernet address is a six-byte opaque identifier (not an integer)
1209 
1210 enum
1211 	{
1212 	mDNSAddrType_None    = 0,
1213 	mDNSAddrType_IPv4    = 4,
1214 	mDNSAddrType_IPv6    = 6,
1215 	mDNSAddrType_Unknown = ~0	// Special marker value used in known answer list recording
1216 	};
1217 
1218 typedef struct
1219 	{
1220 	mDNSs32 type;
1221 	union { mDNSv6Addr v6; mDNSv4Addr v4; } ip;
1222 	} mDNSAddr;
1223 
1224 enum { mDNSfalse = 0, mDNStrue = 1 };
1225 
1226 #define mDNSNULL 0L
1227 
1228 enum
1229 	{
1230 	mStatus_Waiting           = 1,
1231 	mStatus_NoError           = 0,
1232 
1233 	// mDNS return values are in the range FFFE FF00 (-65792) to FFFE FFFF (-65537)
1234 	// The top end of the range (FFFE FFFF) is used for error codes;
1235 	// the bottom end of the range (FFFE FF00) is used for non-error values;
1236 
1237 	// Error codes:
1238 	mStatus_UnknownErr                = -65537,		// First value: 0xFFFE FFFF
1239 	mStatus_NoSuchNameErr             = -65538,
1240 	mStatus_NoMemoryErr               = -65539,
1241 	mStatus_BadParamErr               = -65540,
1242 	mStatus_BadReferenceErr           = -65541,
1243 	mStatus_BadStateErr               = -65542,
1244 	mStatus_BadFlagsErr               = -65543,
1245 	mStatus_UnsupportedErr            = -65544,
1246 	mStatus_NotInitializedErr         = -65545,
1247 	mStatus_NoCache                   = -65546,
1248 	mStatus_AlreadyRegistered         = -65547,
1249 	mStatus_NameConflict              = -65548,
1250 	mStatus_Invalid                   = -65549,
1251 	mStatus_Firewall                  = -65550,
1252 	mStatus_Incompatible              = -65551,
1253 	mStatus_BadInterfaceErr           = -65552,
1254 	mStatus_Refused                   = -65553,
1255 	mStatus_NoSuchRecord              = -65554,
1256 	mStatus_NoAuth                    = -65555,
1257 	mStatus_NoSuchKey                 = -65556,
1258 	mStatus_NATTraversal              = -65557,
1259 	mStatus_DoubleNAT                 = -65558,
1260 	mStatus_BadTime                   = -65559,
1261 	mStatus_BadSig                    = -65560,     // while we define this per RFC 2845, BIND 9 returns Refused for bad/missing signatures
1262 	mStatus_BadKey                    = -65561,
1263 	mStatus_TransientErr              = -65562,     // transient failures, e.g. sending packets shortly after a network transition or wake from sleep
1264 	mStatus_ServiceNotRunning         = -65563,     // Background daemon not running
1265 	mStatus_NATPortMappingUnsupported = -65564,     // NAT doesn't support NAT-PMP or UPnP
1266 	mStatus_NATPortMappingDisabled    = -65565,     // NAT supports NAT-PMP or UPnP but it's disabled by the administrator
1267 	mStatus_NoRouter                  = -65566,
1268 	mStatus_PollingMode               = -65567,
1269 	// -65568 to -65786 currently unused; available for allocation
1270 
1271 	// tcp connection status
1272 	mStatus_ConnPending       = -65787,
1273 	mStatus_ConnFailed        = -65788,
1274 	mStatus_ConnEstablished   = -65789,
1275 
1276 	// Non-error values:
1277 	mStatus_GrowCache         = -65790,
1278 	mStatus_ConfigChanged     = -65791,
1279 	mStatus_MemFree           = -65792		// Last value: 0xFFFE FF00
1280 	// mStatus_MemFree is the last legal mDNS error code, at the end of the range allocated for mDNS
1281 	};
1282 
1283 typedef mDNSs32 mStatus;
1284 
1285 // RFC 1034/1035 specify that a domain label consists of a length byte plus up to 63 characters
1286 #define MAX_DOMAIN_LABEL 63
1287 typedef struct { mDNSu8 c[ 64]; } domainlabel;		// One label: length byte and up to 63 characters
1288 
1289 // RFC 1034/1035/2181 specify that a domain name, including length bytes, data bytes, and terminating zero, may be up to 256 bytes long
1290 #define MAX_DOMAIN_NAME 256
1291 typedef struct { mDNSu8 c[256]; } domainname;		// Up to 256 bytes of length-prefixed domainlabels
1292 
1293 typedef struct { mDNSu8 c[256]; } UTF8str255;		// Null-terminated C string
1294 
1295 // The longest legal textual form of a DNS name is 1009 bytes, including the C-string terminating NULL at the end.
1296 // Explanation:
1297 // When a native domainname object is converted to printable textual form using ConvertDomainNameToCString(),
1298 // non-printing characters are represented in the conventional DNS way, as '\ddd', where ddd is a three-digit decimal number.
1299 // The longest legal domain name is 256 bytes, in the form of four labels as shown below:
1300 // Length byte, 63 data bytes, length byte, 63 data bytes, length byte, 63 data bytes, length byte, 62 data bytes, zero byte.
1301 // Each label is encoded textually as characters followed by a trailing dot.
1302 // If every character has to be represented as a four-byte escape sequence, then this makes the maximum textual form four labels
1303 // plus the C-string terminating NULL as shown below:
1304 // 63*4+1 + 63*4+1 + 63*4+1 + 62*4+1 + 1 = 1009.
1305 // Note that MAX_ESCAPED_DOMAIN_LABEL is not normally used: If you're only decoding a single label, escaping is usually not required.
1306 // It is for domain names, where dots are used as label separators, that proper escaping is vital.
1307 #define MAX_ESCAPED_DOMAIN_LABEL 254
1308 #define MAX_ESCAPED_DOMAIN_NAME 1009
1309 
1310 // MAX_REVERSE_MAPPING_NAME
1311 // For IPv4: "123.123.123.123.in-addr.arpa."  30 bytes including terminating NUL
1312 // For IPv6: "x.x.x.x.x.x.x.x.x.x.x.x.x.x.x.x.x.x.x.x.x.x.x.x.x.x.x.x.x.x.x.x.ip6.arpa."  74 bytes including terminating NUL
1313 
1314 #define MAX_REVERSE_MAPPING_NAME_V4 30
1315 #define MAX_REVERSE_MAPPING_NAME_V6 74
1316 #define MAX_REVERSE_MAPPING_NAME    74
1317 
1318 // Most records have a TTL of 75 minutes, so that their 80% cache-renewal query occurs once per hour.
1319 // For records containing a hostname (in the name on the left, or in the rdata on the right),
1320 // like A, AAAA, reverse-mapping PTR, and SRV, we use a two-minute TTL by default, because we don't want
1321 // them to hang around for too long in the cache if the host in question crashes or otherwise goes away.
1322 
1323 #define kStandardTTL (3600UL * 100 / 80)
1324 #define kHostNameTTL 120UL
1325 
1326 #define DefaultTTLforRRType(X) (((X) == kDNSType_A || (X) == kDNSType_AAAA || (X) == kDNSType_SRV) ? kHostNameTTL : kStandardTTL)
1327 
1328 typedef struct AuthRecord_struct AuthRecord;
1329 typedef struct ServiceRecordSet_struct ServiceRecordSet;
1330 typedef struct CacheRecord_struct CacheRecord;
1331 typedef struct CacheGroup_struct CacheGroup;
1332 typedef struct DNSQuestion_struct DNSQuestion;
1333 typedef struct ZoneData_struct ZoneData;
1334 typedef struct mDNS_struct mDNS;
1335 typedef struct mDNS_PlatformSupport_struct mDNS_PlatformSupport;
1336 typedef struct NATTraversalInfo_struct NATTraversalInfo;
1337 
1338 // Structure to abstract away the differences between TCP/SSL sockets, and one for UDP sockets
1339 // The actual definition of these structures appear in the appropriate platform support code
1340 typedef struct TCPSocket_struct TCPSocket;
1341 typedef struct UDPSocket_struct UDPSocket;
1342 
1343 // ***************************************************************************
1344 #if 0
1345 #pragma mark -
1346 #pragma mark - DNS Message structures
1347 #endif
1348 
1349 #define mDNS_numZones   numQuestions
1350 #define mDNS_numPrereqs numAnswers
1351 #define mDNS_numUpdates numAuthorities
1352 
1353 typedef packedstruct
1354 	{
1355 	mDNSOpaque16 id;
1356 	mDNSOpaque16 flags;
1357 	mDNSu16 numQuestions;
1358 	mDNSu16 numAnswers;
1359 	mDNSu16 numAuthorities;
1360 	mDNSu16 numAdditionals;
1361 	} DNSMessageHeader;
1362 
1363 // We can send and receive packets up to 9000 bytes (Ethernet Jumbo Frame size, if that ever becomes widely used)
1364 // However, in the normal case we try to limit packets to 1500 bytes so that we don't get IP fragmentation on standard Ethernet
1365 // 40 (IPv6 header) + 8 (UDP header) + 12 (DNS message header) + 1440 (DNS message body) = 1500 total
1366 #define AbsoluteMaxDNSMessageData 8940
1367 #define NormalMaxDNSMessageData 1440
1368 typedef packedstruct
1369 	{
1370 	DNSMessageHeader h;						// Note: Size 12 bytes
1371 	mDNSu8 data[AbsoluteMaxDNSMessageData];	// 40 (IPv6) + 8 (UDP) + 12 (DNS header) + 8940 (data) = 9000
1372 	} DNSMessage;
1373 
1374 typedef struct tcpInfo_t
1375 	{
1376 	mDNS             *m;
1377 	TCPSocket        *sock;
1378 	DNSMessage        request;
1379 	int               requestLen;
1380 	DNSQuestion      *question;   // For queries
1381 	ServiceRecordSet *srs;        // For service record updates
1382 	AuthRecord       *rr;         // For record updates
1383 	mDNSAddr          Addr;
1384 	mDNSIPPort        Port;
1385 	DNSMessage       *reply;
1386 	mDNSu16           replylen;
1387 	unsigned long     nread;
1388 	int               numReplies;
1389 	} tcpInfo_t;
1390 
1391 // ***************************************************************************
1392 #if 0
1393 #pragma mark -
1394 #pragma mark - Other Packet Format Structures
1395 #endif
1396 
1397 typedef packedstruct
1398 	{
1399 	mDNSEthAddr  dst;
1400 	mDNSEthAddr  src;
1401 	mDNSOpaque16 ethertype;
1402 	} EthernetHeader;		// 14 bytes
1403 
1404 typedef packedstruct
1405 	{
1406 	mDNSOpaque16 hrd;
1407 	mDNSOpaque16 pro;
1408 	mDNSu8       hln;
1409 	mDNSu8       pln;
1410 	mDNSOpaque16 op;
1411 	mDNSEthAddr  sha;
1412 	mDNSv4Addr   spa;
1413 	mDNSEthAddr  tha;
1414 	mDNSv4Addr   tpa;
1415 	} ARP_EthIP;			// 28 bytes
1416 
1417 typedef packedstruct
1418 	{
1419 	mDNSu8       vlen;
1420 	mDNSu8       tos;
1421 	mDNSu16      totlen;
1422 	mDNSOpaque16 id;
1423 	mDNSOpaque16 flagsfrags;
1424 	mDNSu8       ttl;
1425 	mDNSu8       protocol;
1426 	mDNSu16      checksum;
1427 	mDNSv4Addr   src;
1428 	mDNSv4Addr   dst;
1429 	} IPv4Header;			// 20 bytes
1430 
1431 typedef packedstruct
1432 	{
1433 	mDNSu32      vcf;		// Version, Traffic Class, Flow Label
1434 	mDNSu16      len;		// Payload Length
1435 	mDNSu8       protocol;	// Type of next header: 0x06 = TCP, 0x11 = UDP, 0x3A = ICMPv6
1436 	mDNSu8       ttl;		// Hop Limit
1437 	mDNSv6Addr   src;
1438 	mDNSv6Addr   dst;
1439 	} IPv6Header;			// 40 bytes
1440 
1441 typedef packedstruct
1442 	{
1443 	mDNSu8       type;		// 0x87 == Neighbor Solicitation, 0x88 == Neighbor Advertisement
1444 	mDNSu8       code;
1445 	mDNSu16      checksum;
1446 	mDNSu32      reserved;
1447 	mDNSv6Addr   target;
1448 	} IPv6ND;				// 24 bytes
1449 
1450 typedef packedstruct
1451 	{
1452 	mDNSIPPort   src;
1453 	mDNSIPPort   dst;
1454 	mDNSu16      len;		// Length including UDP header (ie. minimum value is 8 bytes)
1455 	mDNSu16      checksum;
1456 	} UDPHeader;			// 8 bytes
1457 
1458 typedef packedstruct
1459 	{
1460 	mDNSIPPort   src;
1461 	mDNSIPPort   dst;
1462 	mDNSu32      seq;
1463 	mDNSu32      ack;
1464 	mDNSu8       offset;
1465 	mDNSu8       flags;
1466 	mDNSu16      window;
1467 	mDNSu16      checksum;
1468 	mDNSu16      urgent;
1469 	} TCPHeader;			// 20 bytes
1470 
1471 // ***************************************************************************
1472 #if 0
1473 #pragma mark -
1474 #pragma mark - Resource Record structures
1475 #endif
1476 
1477 // Authoritative Resource Records:
1478 // There are four basic types: Shared, Advisory, Unique, Known Unique
1479 
1480 // * Shared Resource Records do not have to be unique
1481 // -- Shared Resource Records are used for DNS-SD service PTRs
1482 // -- It is okay for several hosts to have RRs with the same name but different RDATA
1483 // -- We use a random delay on responses to reduce collisions when all the hosts respond to the same query
1484 // -- These RRs typically have moderately high TTLs (e.g. one hour)
1485 // -- These records are announced on startup and topology changes for the benefit of passive listeners
1486 // -- These records send a goodbye packet when deregistering
1487 //
1488 // * Advisory Resource Records are like Shared Resource Records, except they don't send a goodbye packet
1489 //
1490 // * Unique Resource Records should be unique among hosts within any given mDNS scope
1491 // -- The majority of Resource Records are of this type
1492 // -- If two entities on the network have RRs with the same name but different RDATA, this is a conflict
1493 // -- Responses may be sent immediately, because only one host should be responding to any particular query
1494 // -- These RRs typically have low TTLs (e.g. a few minutes)
1495 // -- On startup and after topology changes, a host issues queries to verify uniqueness
1496 
1497 // * Known Unique Resource Records are treated like Unique Resource Records, except that mDNS does
1498 // not have to verify their uniqueness because this is already known by other means (e.g. the RR name
1499 // is derived from the host's IP or Ethernet address, which is already known to be a unique identifier).
1500 
1501 // Summary of properties of different record types:
1502 // Probe?    Does this record type send probes before announcing?
1503 // Conflict? Does this record type react if we observe an apparent conflict?
1504 // Goodbye?  Does this record type send a goodbye packet on departure?
1505 //
1506 //               Probe? Conflict? Goodbye? Notes
1507 // Unregistered                            Should not appear in any list (sanity check value)
1508 // Shared         No      No       Yes     e.g. Service PTR record
1509 // Deregistering  No      No       Yes     Shared record about to announce its departure and leave the list
1510 // Advisory       No      No       No
1511 // Unique         Yes     Yes      No      Record intended to be unique -- will probe to verify
1512 // Verified       Yes     Yes      No      Record has completed probing, and is verified unique
1513 // KnownUnique    No      Yes      No      Record is assumed by other means to be unique
1514 
1515 // Valid lifecycle of a record:
1516 // Unregistered ->                   Shared      -> Deregistering -(goodbye)-> Unregistered
1517 // Unregistered ->                   Advisory                               -> Unregistered
1518 // Unregistered -> Unique -(probe)-> Verified                               -> Unregistered
1519 // Unregistered ->                   KnownUnique                            -> Unregistered
1520 
1521 // Each Authoritative kDNSRecordType has only one bit set. This makes it easy to quickly see if a record
1522 // is one of a particular set of types simply by performing the appropriate bitwise masking operation.
1523 
1524 // Cache Resource Records (received from the network):
1525 // There are four basic types: Answer, Unique Answer, Additional, Unique Additional
1526 // Bit 7 (the top bit) of kDNSRecordType is always set for Cache Resource Records; always clear for Authoritative Resource Records
1527 // Bit 6 (value 0x40) is set for answer records; clear for authority/additional records
1528 // Bit 5 (value 0x20) is set for records received with the kDNSClass_UniqueRRSet
1529 
1530 enum
1531 	{
1532 	kDNSRecordTypeUnregistered     = 0x00,	// Not currently in any list
1533 	kDNSRecordTypeDeregistering    = 0x01,	// Shared record about to announce its departure and leave the list
1534 
1535 	kDNSRecordTypeUnique           = 0x02,	// Will become a kDNSRecordTypeVerified when probing is complete
1536 
1537 	kDNSRecordTypeAdvisory         = 0x04,	// Like Shared, but no goodbye packet
1538 	kDNSRecordTypeShared           = 0x08,	// Shared means record name does not have to be unique -- use random delay on responses
1539 
1540 	kDNSRecordTypeVerified         = 0x10,	// Unique means mDNS should check that name is unique (and then send immediate responses)
1541 	kDNSRecordTypeKnownUnique      = 0x20,	// Known Unique means mDNS can assume name is unique without checking
1542 	                                        // For Dynamic Update records, Known Unique means the record must already exist on the server.
1543 	kDNSRecordTypeUniqueMask       = (kDNSRecordTypeUnique | kDNSRecordTypeVerified | kDNSRecordTypeKnownUnique),
1544 	kDNSRecordTypeActiveMask       = (kDNSRecordTypeAdvisory | kDNSRecordTypeShared | kDNSRecordTypeVerified | kDNSRecordTypeKnownUnique),
1545 
1546 	kDNSRecordTypePacketAdd        = 0x80,	// Received in the Additional  Section of a DNS Response
1547 	kDNSRecordTypePacketAddUnique  = 0x90,	// Received in the Additional  Section of a DNS Response with kDNSClass_UniqueRRSet set
1548 	kDNSRecordTypePacketAuth       = 0xA0,	// Received in the Authorities Section of a DNS Response
1549 	kDNSRecordTypePacketAuthUnique = 0xB0,	// Received in the Authorities Section of a DNS Response with kDNSClass_UniqueRRSet set
1550 	kDNSRecordTypePacketAns        = 0xC0,	// Received in the Answer      Section of a DNS Response
1551 	kDNSRecordTypePacketAnsUnique  = 0xD0,	// Received in the Answer      Section of a DNS Response with kDNSClass_UniqueRRSet set
1552 
1553 	kDNSRecordTypePacketNegative   = 0xF0,	// Pseudo-RR generated to cache non-existence results like NXDomain
1554 
1555 	kDNSRecordTypePacketUniqueMask = 0x10	// True for PacketAddUnique, PacketAnsUnique, PacketAuthUnique
1556 	};
1557 
1558 typedef packedstruct { mDNSu16 priority; mDNSu16 weight; mDNSIPPort port; domainname target;   } rdataSRV;
1559 typedef packedstruct { mDNSu16 preference;                                domainname exchange; } rdataMX;
1560 typedef packedstruct { domainname mbox; domainname txt;                                        } rdataRP;
1561 typedef packedstruct { mDNSu16 preference; domainname map822; domainname mapx400;              } rdataPX;
1562 
1563 typedef packedstruct
1564 	{
1565 	domainname mname;
1566 	domainname rname;
1567 	mDNSs32 serial;		// Modular counter; increases when zone changes
1568 	mDNSu32 refresh;	// Time in seconds that a slave waits after successful replication of the database before it attempts replication again
1569 	mDNSu32 retry;		// Time in seconds that a slave waits after an unsuccessful replication attempt before it attempts replication again
1570 	mDNSu32 expire;		// Time in seconds that a slave holds on to old data while replication attempts remain unsuccessful
1571 	mDNSu32 min;		// Nominally the minimum record TTL for this zone, in seconds; also used for negative caching.
1572 	} rdataSOA;
1573 
1574 // EDNS Option Code registrations are recorded in the "DNS EDNS0 Options" section of
1575 // <http://www.iana.org/assignments/dns-parameters>
1576 
1577 #define kDNSOpt_LLQ   1
1578 #define kDNSOpt_Lease 2
1579 #define kDNSOpt_NSID  3
1580 #define kDNSOpt_Owner 4
1581 
1582 typedef struct
1583 	{
1584 	mDNSu16      vers;
1585 	mDNSu16      llqOp;
1586 	mDNSu16      err;	// Or UDP reply port, in setup request
1587 	// Note: In the in-memory form, there's typically a two-byte space here, so that the following 64-bit id is word-aligned
1588 	mDNSOpaque64 id;
1589 	mDNSu32      llqlease;
1590 	} LLQOptData;
1591 
1592 typedef struct
1593 	{
1594 	mDNSu8       vers;		// Version number of this Owner OPT record
1595 	mDNSs8       seq;		// Sleep/wake epoch
1596 	mDNSEthAddr  HMAC;		// Host's primary identifier (e.g. MAC of on-board Ethernet)
1597 	mDNSEthAddr  IMAC;		// Interface's MAC address (if different to primary MAC)
1598 	mDNSOpaque48 password;	// Optional password
1599 	} OwnerOptData;
1600 
1601 // Note: rdataOPT format may be repeated an arbitrary number of times in a single resource record
1602 typedef packedstruct
1603 	{
1604 	mDNSu16 opt;
1605 	mDNSu16 optlen;
1606 	union { LLQOptData llq; mDNSu32 updatelease; OwnerOptData owner; } u;
1607 	} rdataOPT;
1608 
1609 // Space needed to put OPT records into a packet:
1610 // Header      11 bytes (name 1, type 2, class 2, TTL 4, length 2)
1611 // LLQ rdata   18 bytes (opt 2, len 2, vers 2, op 2, err 2, id 8, lease 4)
1612 // Lease rdata  8 bytes (opt 2, len 2, lease 4)
1613 // Owner rdata 12-24    (opt 2, len 2, owner 8-20)
1614 
1615 #define DNSOpt_Header_Space                 11
1616 #define DNSOpt_LLQData_Space               (4 + 2 + 2 + 2 + 8 + 4)
1617 #define DNSOpt_LeaseData_Space             (4 + 4)
1618 #define DNSOpt_OwnerData_ID_Space          (4 + 2 + 6)
1619 #define DNSOpt_OwnerData_ID_Wake_Space     (4 + 2 + 6 + 6)
1620 #define DNSOpt_OwnerData_ID_Wake_PW4_Space (4 + 2 + 6 + 6 + 4)
1621 #define DNSOpt_OwnerData_ID_Wake_PW6_Space (4 + 2 + 6 + 6 + 6)
1622 
1623 #define ValidOwnerLength(X) (	(X) == DNSOpt_OwnerData_ID_Space          - 4 || \
1624 								(X) == DNSOpt_OwnerData_ID_Wake_Space     - 4 || \
1625 								(X) == DNSOpt_OwnerData_ID_Wake_PW4_Space - 4 || \
1626 								(X) == DNSOpt_OwnerData_ID_Wake_PW6_Space - 4    )
1627 
1628 #define ValidDNSOpt(O) (((O)->opt == kDNSOpt_LLQ   && (O)->optlen == DNSOpt_LLQData_Space   - 4) || \
1629 						((O)->opt == kDNSOpt_Lease && (O)->optlen == DNSOpt_LeaseData_Space - 4) || \
1630 						((O)->opt == kDNSOpt_Owner && ValidOwnerLength((O)->optlen)            )    )
1631 
1632 #define DNSOpt_Owner_Space(O) (mDNSSameEthAddress(&(O)->u.owner.HMAC, &(O)->u.owner.IMAC) ? DNSOpt_OwnerData_ID_Space : DNSOpt_OwnerData_ID_Wake_Space)
1633 
1634 #define DNSOpt_Data_Space(O) (                                  \
1635 	(O)->opt == kDNSOpt_LLQ   ? DNSOpt_LLQData_Space   :        \
1636 	(O)->opt == kDNSOpt_Lease ? DNSOpt_LeaseData_Space :        \
1637 	(O)->opt == kDNSOpt_Owner ? DNSOpt_Owner_Space(O)  : 0x10000)
1638 
1639 // A maximal NSEC record is:
1640 //   256 bytes domainname 'nextname'
1641 // + 256 * 34 = 8704 bytes of bitmap data
1642 // = 8960 bytes total
1643 // For now we only support NSEC records encoding DNS types 0-255 and ignore the nextname (we always set it to be the same as the rrname),
1644 // which gives us a fixed in-memory size of 32 bytes (256 bits)
1645 typedef struct
1646 	{
1647 	mDNSu8 bitmap[32];
1648 	} rdataNSEC;
1649 
1650 // StandardAuthRDSize is 264 (256+8), which is large enough to hold a maximum-sized SRV record (6 + 256 bytes)
1651 // MaximumRDSize is 8K the absolute maximum we support (at least for now)
1652 #define StandardAuthRDSize 264
1653 #define MaximumRDSize 8192
1654 
1655 // InlineCacheRDSize is 68
1656 // Records received from the network with rdata this size or less have their rdata stored right in the CacheRecord object
1657 // Records received from the network with rdata larger than this have additional storage allocated for the rdata
1658 // A quick unscientific sample from a busy network at Apple with lots of machines revealed this:
1659 // 1461 records in cache
1660 // 292 were one-byte TXT records
1661 // 136 were four-byte A records
1662 // 184 were sixteen-byte AAAA records
1663 // 780 were various PTR, TXT and SRV records from 12-64 bytes
1664 // Only 69 records had rdata bigger than 64 bytes
1665 // Note that since CacheRecord object and a CacheGroup object are allocated out of the same pool, it's sensible to
1666 // have them both be the same size. Making one smaller without making the other smaller won't actually save any memory.
1667 #define InlineCacheRDSize 68
1668 
1669 // On 64-bit, the pointers in a CacheRecord are bigger, and that creates 8 bytes more space for the name in a CacheGroup
1670 #if ENABLE_MULTI_PACKET_QUERY_SNOOPING
1671 	#if defined(_ILP64) || defined(__ILP64__) || defined(_LP64) || defined(__LP64__) || defined(_WIN64)
1672 	#define InlineCacheGroupNameSize 152
1673 	#else
1674 	#define InlineCacheGroupNameSize 144
1675 	#endif
1676 #else
1677 	#if defined(_ILP64) || defined(__ILP64__) || defined(_LP64) || defined(__LP64__) || defined(_WIN64)
1678 	#define InlineCacheGroupNameSize 136
1679 	#else
1680 	#define InlineCacheGroupNameSize 128
1681 	#endif
1682 #endif
1683 
1684 // The RDataBody union defines the common rdata types that fit into our 264-byte limit
1685 typedef union
1686 	{
1687 	mDNSu8      data[StandardAuthRDSize];
1688 	mDNSv4Addr  ipv4;		// For 'A' record
1689 	domainname  name;		// For PTR, NS, CNAME, DNAME
1690 	UTF8str255  txt;
1691 	rdataMX     mx;
1692 	mDNSv6Addr  ipv6;		// For 'AAAA' record
1693 	rdataSRV    srv;
1694 	rdataOPT    opt[2];		// For EDNS0 OPT record; RDataBody may contain multiple variable-length rdataOPT objects packed together
1695 	rdataNSEC   nsec;
1696 	} RDataBody;
1697 
1698 // The RDataBody2 union is the same as above, except it includes fields for the larger types like soa, rp, px
1699 typedef union
1700 	{
1701 	mDNSu8      data[StandardAuthRDSize];
1702 	mDNSv4Addr  ipv4;		// For 'A' record
1703 	domainname  name;		// For PTR, NS, CNAME, DNAME
1704 	rdataSOA    soa;		// This is large; not included in the normal RDataBody definition
1705 	UTF8str255  txt;
1706 	rdataMX     mx;
1707 	rdataRP     rp;			// This is large; not included in the normal RDataBody definition
1708 	rdataPX     px;			// This is large; not included in the normal RDataBody definition
1709 	mDNSv6Addr  ipv6;		// For 'AAAA' record
1710 	rdataSRV    srv;
1711 	rdataOPT    opt[2];		// For EDNS0 OPT record; RDataBody may contain multiple variable-length rdataOPT objects packed together
1712 	rdataNSEC   nsec;
1713 	} RDataBody2;
1714 
1715 typedef struct
1716 	{
1717 	mDNSu16    MaxRDLength;	// Amount of storage allocated for rdata (usually sizeof(RDataBody))
1718 	mDNSu16    padding;		// So that RDataBody is aligned on 32-bit boundary
1719 	RDataBody  u;
1720 	} RData;
1721 
1722 // sizeofRDataHeader should be 4 bytes
1723 #define sizeofRDataHeader (sizeof(RData) - sizeof(RDataBody))
1724 
1725 // RData_small is a smaller version of the RData object, used for inline data storage embedded in a CacheRecord_struct
1726 typedef struct
1727 	{
1728 	mDNSu16    MaxRDLength;	// Storage allocated for data (may be greater than InlineCacheRDSize if additional storage follows this object)
1729 	mDNSu16    padding;		// So that data is aligned on 32-bit boundary
1730 	mDNSu8     data[InlineCacheRDSize];
1731 	} RData_small;
1732 
1733 // Note: Within an mDNSRecordCallback mDNS all API calls are legal except mDNS_Init(), mDNS_Exit(), mDNS_Execute()
1734 typedef void mDNSRecordCallback(mDNS *const m, AuthRecord *const rr, mStatus result);
1735 
1736 // Note:
1737 // Restrictions: An mDNSRecordUpdateCallback may not make any mDNS API calls.
1738 // The intent of this callback is to allow the client to free memory, if necessary.
1739 // The internal data structures of the mDNS code may not be in a state where mDNS API calls may be made safely.
1740 typedef void mDNSRecordUpdateCallback(mDNS *const m, AuthRecord *const rr, RData *OldRData);
1741 
1742 // ***************************************************************************
1743 #if 0
1744 #pragma mark -
1745 #pragma mark - NAT Traversal structures and constants
1746 #endif
1747 
1748 #define NATMAP_MAX_RETRY_INTERVAL    ((mDNSPlatformOneSecond * 60) * 15)    // Max retry interval is 15 minutes
1749 #define NATMAP_MIN_RETRY_INTERVAL     (mDNSPlatformOneSecond * 2)           // Min retry interval is 2 seconds
1750 #define NATMAP_INIT_RETRY             (mDNSPlatformOneSecond / 4)           // start at 250ms w/ exponential decay
1751 #define NATMAP_DEFAULT_LEASE          (60 * 60 * 2)                         // 2 hour lease life in seconds
1752 #define NATMAP_VERS 0
1753 
1754 typedef enum
1755 	{
1756 	NATOp_AddrRequest    = 0,
1757 	NATOp_MapUDP         = 1,
1758 	NATOp_MapTCP         = 2,
1759 
1760 	NATOp_AddrResponse   = 0x80 | 0,
1761 	NATOp_MapUDPResponse = 0x80 | 1,
1762 	NATOp_MapTCPResponse = 0x80 | 2,
1763 	} NATOp_t;
1764 
1765 enum
1766 	{
1767 	NATErr_None    = 0,
1768 	NATErr_Vers    = 1,
1769 	NATErr_Refused = 2,
1770 	NATErr_NetFail = 3,
1771 	NATErr_Res     = 4,
1772 	NATErr_Opcode  = 5
1773 	};
1774 
1775 typedef mDNSu16 NATErr_t;
1776 
1777 typedef packedstruct
1778 	{
1779 	mDNSu8 vers;
1780 	mDNSu8 opcode;
1781 	} NATAddrRequest;
1782 
1783 typedef packedstruct
1784 	{
1785 	mDNSu8     vers;
1786 	mDNSu8     opcode;
1787 	mDNSu16    err;
1788 	mDNSu32    upseconds;		// Time since last NAT engine reboot, in seconds
1789 	mDNSv4Addr ExtAddr;
1790 	} NATAddrReply;
1791 
1792 typedef packedstruct
1793 	{
1794 	mDNSu8 vers;
1795 	mDNSu8 opcode;
1796 	mDNSOpaque16 unused;
1797 	mDNSIPPort intport;
1798 	mDNSIPPort extport;
1799 	mDNSu32    NATReq_lease;
1800 	} NATPortMapRequest;
1801 
1802 typedef packedstruct
1803 	{
1804 	mDNSu8     vers;
1805 	mDNSu8     opcode;
1806 	mDNSu16    err;
1807 	mDNSu32    upseconds;		// Time since last NAT engine reboot, in seconds
1808 	mDNSIPPort intport;
1809 	mDNSIPPort extport;
1810 	mDNSu32    NATRep_lease;
1811 	} NATPortMapReply;
1812 
1813 typedef enum
1814 	{
1815 	LNTDiscoveryOp      = 1,
1816 	LNTExternalAddrOp   = 2,
1817 	LNTPortMapOp        = 3,
1818 	LNTPortMapDeleteOp  = 4
1819 	} LNTOp_t;
1820 
1821 #define LNT_MAXBUFSIZE 8192
1822 typedef struct tcpLNTInfo_struct tcpLNTInfo;
1823 struct tcpLNTInfo_struct
1824 	{
1825 	tcpLNTInfo       *next;
1826 	mDNS             *m;
1827 	NATTraversalInfo *parentNATInfo;	// pointer back to the parent NATTraversalInfo
1828 	TCPSocket        *sock;
1829 	LNTOp_t           op;				// operation performed using this connection
1830 	mDNSAddr          Address;			// router address
1831 	mDNSIPPort        Port;				// router port
1832 	mDNSs8           *Request;			// xml request to router
1833 	int               requestLen;
1834 	mDNSs8           *Reply;			// xml reply from router
1835 	int               replyLen;
1836 	unsigned long     nread;			// number of bytes read so far
1837 	int               retries;			// number of times we've tried to do this port mapping
1838 	};
1839 
1840 typedef void (*NATTraversalClientCallback)(mDNS *m, NATTraversalInfo *n);
1841 
1842 // if m->timenow <  ExpiryTime then we have an active mapping, and we'll renew halfway to expiry
1843 // if m->timenow >= ExpiryTime then our mapping has expired, and we're trying to create one
1844 
1845 struct NATTraversalInfo_struct
1846 	{
1847 	// Internal state fields. These are used internally by mDNSCore; the client layer needn't be concerned with them.
1848 	NATTraversalInfo           *next;
1849 
1850 	mDNSs32                     ExpiryTime;			// Time this mapping expires, or zero if no mapping
1851 	mDNSs32                     retryInterval;		// Current interval, between last packet we sent and the next one
1852 	mDNSs32                     retryPortMap;		// If Protocol is nonzero, time to send our next mapping packet
1853 	mStatus                     NewResult;			// New error code; will be copied to Result just prior to invoking callback
1854 
1855 #ifdef _LEGACY_NAT_TRAVERSAL_
1856 	tcpLNTInfo                  tcpInfo;			// Legacy NAT traversal (UPnP) TCP connection
1857 #endif
1858 
1859 	// Result fields: When the callback is invoked these fields contain the answers the client is looking for
1860 	// When the callback is invoked ExternalPort is *usually* set to be the same the same as RequestedPort, except:
1861 	// (a) When we're behind a NAT gateway with port mapping disabled, ExternalPort is reported as zero to
1862 	//     indicate that we don't currently have a working mapping (but RequestedPort retains the external port
1863 	//     we'd like to get, the next time we meet an accomodating NAT gateway willing to give us one).
1864 	// (b) When we have a routable non-RFC1918 address, we don't *need* a port mapping, so ExternalPort
1865 	//     is reported as the same as our InternalPort, since that is effectively our externally-visible port too.
1866 	//     Again, RequestedPort retains the external port we'd like to get the next time we find ourself behind a NAT gateway.
1867 	// To improve stability of port mappings, RequestedPort is updated any time we get a successful
1868 	// mapping response from the NAT-PMP or UPnP gateway. For example, if we ask for port 80, and
1869 	// get assigned port 81, then thereafter we'll contine asking for port 81.
1870 	mDNSInterfaceID             InterfaceID;
1871 	mDNSv4Addr                  ExternalAddress;	// Initially set to onesIPv4Addr, until first callback
1872 	mDNSIPPort                  ExternalPort;
1873 	mDNSu32                     Lifetime;
1874 	mStatus                     Result;
1875 
1876 	// Client API fields: The client must set up these fields *before* making any NAT traversal API calls
1877 	mDNSu8                      Protocol;			// NATOp_MapUDP or NATOp_MapTCP, or zero if just requesting the external IP address
1878 	mDNSIPPort                  IntPort;			// Client's internal port number (doesn't change)
1879 	mDNSIPPort                  RequestedPort;		// Requested external port; may be updated with actual value assigned by gateway
1880 	mDNSu32                     NATLease;			// Requested lifetime in seconds (doesn't change)
1881 	NATTraversalClientCallback  clientCallback;
1882 	void                       *clientContext;
1883 	};
1884 
1885 typedef struct							// Size is 36 bytes when compiling for 32-bit; 48 when compiling for 64-bit
1886 	{
1887 	mDNSu8           RecordType;		// See enum above
1888 	mDNSu16          rrtype;
1889 	mDNSu16          rrclass;
1890 	mDNSu32          rroriginalttl;		// In seconds
1891 	mDNSu16          rdlength;			// Size of the raw rdata, in bytes, in the on-the-wire format
1892 										// (In-memory storage may be larger, for structures containing 'holes', like SOA,
1893 										// or smaller, for NSEC where we don't bother storing the nextname field)
1894 	mDNSu16          rdestimate;		// Upper bound on on-the-wire size of rdata after name compression
1895 	mDNSu32          namehash;			// Name-based (i.e. case-insensitive) hash of name
1896 	mDNSu32          rdatahash;			// For rdata containing domain name (e.g. PTR, SRV, CNAME etc.), case-insensitive name hash
1897 										// else, for all other rdata, 32-bit hash of the raw rdata
1898 										// Note: This requirement is important. Various routines like AddAdditionalsToResponseList(),
1899 										// ReconfirmAntecedents(), etc., use rdatahash as a pre-flight check to see
1900 										// whether it's worth doing a full SameDomainName() call. If the rdatahash
1901 										// is not a correct case-insensitive name hash, they'll get false negatives.
1902 
1903 	// Grouping pointers together at the end of the structure improves the memory layout efficiency
1904 	mDNSInterfaceID  InterfaceID;		// Set if this RR is specific to one interface
1905 										// For records received off the wire, InterfaceID is *always* set to the receiving interface
1906 										// For our authoritative records, InterfaceID is usually zero, except for those few records
1907 										// that are interface-specific (e.g. address records, especially linklocal addresses)
1908 	const domainname *name;
1909 	RData           *rdata;				// Pointer to storage for this rdata
1910 	} ResourceRecord;
1911 
1912 // Unless otherwise noted, states may apply to either independent record registrations or service registrations
1913 typedef enum
1914 	{
1915 	regState_Zero              = 0,
1916 	regState_FetchingZoneData  = 1,     // getting info - update not sent
1917 	regState_Pending           = 2,     // update sent, reply not received
1918 	regState_Registered        = 3,     // update sent, reply received
1919 	regState_DeregPending      = 4,     // dereg sent, reply not received
1920 	regState_DeregDeferred     = 5,     // dereg requested while in Pending state - send dereg AFTER registration is confirmed
1921 	regState_Unregistered      = 8,     // not in any list
1922 	regState_Refresh           = 9,     // outstanding refresh (or target change) message
1923 	regState_NATMap            = 10,    // establishing NAT port mapping (service registrations only)
1924 	regState_UpdatePending     = 11,    // update in flight as result of mDNS_Update call
1925 	regState_NoTarget          = 12,    // service registration pending registration of hostname (ServiceRegistrations only)
1926 	regState_ExtraQueued       = 13,    // extra record to be registered upon completion of service registration (RecordRegistrations only)
1927 	regState_NATError          = 14     // unable to complete NAT traversal
1928 	} regState_t;
1929 
1930 enum
1931 	{
1932 	Target_Manual = 0,
1933 	Target_AutoHost = 1,
1934 	Target_AutoHostAndNATMAP = 2
1935 	};
1936 
1937 struct AuthRecord_struct
1938 	{
1939 	// For examples of how to set up this structure for use in mDNS_Register(),
1940 	// see mDNS_AdvertiseInterface() or mDNS_RegisterService().
1941 	// Basically, resrec and persistent metadata need to be set up before calling mDNS_Register().
1942 	// mDNS_SetupResourceRecord() is avaliable as a helper routine to set up most fields to sensible default values for you
1943 
1944 	AuthRecord     *next;				// Next in list; first element of structure for efficiency reasons
1945 	// Field Group 1: Common ResourceRecord fields
1946 	ResourceRecord  resrec;				// 36 bytes when compiling for 32-bit; 48 when compiling for 64-bit
1947 
1948 	// Field Group 2: Persistent metadata for Authoritative Records
1949 	AuthRecord     *Additional1;		// Recommended additional record to include in response (e.g. SRV for PTR record)
1950 	AuthRecord     *Additional2;		// Another additional (e.g. TXT for PTR record)
1951 	AuthRecord     *DependentOn;		// This record depends on another for its uniqueness checking
1952 	AuthRecord     *RRSet;				// This unique record is part of an RRSet
1953 	mDNSRecordCallback *RecordCallback;	// Callback function to call for state changes, and to free memory asynchronously on deregistration
1954 	void           *RecordContext;		// Context parameter for the callback function
1955 	mDNSu8          AutoTarget;			// Set if the target of this record (PTR, CNAME, SRV, etc.) is our host name
1956 	mDNSu8          AllowRemoteQuery;	// Set if we allow hosts not on the local link to query this record
1957 	mDNSu8          ForceMCast;			// Set by client to advertise solely via multicast, even for apparently unicast names
1958 
1959 	OwnerOptData    WakeUp;				// Fpr Sleep Proxy records, MAC address of original owner (so we can wake it)
1960 	mDNSAddr        AddressProxy;		// For reverse-mapping Sleep Proxy PTR records, address in question
1961 	mDNSs32         TimeRcvd;			// In platform time units
1962 	mDNSs32         TimeExpire;			// In platform time units
1963 
1964 
1965 	// Field Group 3: Transient state for Authoritative Records
1966 	mDNSu8          Acknowledged;		// Set if we've given the success callback to the client
1967 	mDNSu8          ProbeCount;			// Number of probes remaining before this record is valid (kDNSRecordTypeUnique)
1968 	mDNSu8          AnnounceCount;		// Number of announcements remaining (kDNSRecordTypeShared)
1969 	mDNSu8          RequireGoodbye;		// Set if this RR has been announced on the wire and will require a goodbye packet
1970 	mDNSu8          AnsweredLocalQ;		// Set if this AuthRecord has been delivered to any local question (LocalOnly or mDNSInterface_Any)
1971 	mDNSu8          IncludeInProbe;		// Set if this RR is being put into a probe right now
1972 	mDNSu8          ImmedUnicast;		// Set if we may send our response directly via unicast to the requester
1973 	mDNSInterfaceID SendNSECNow;		// Set if we need to generate associated NSEC data for this rrname
1974 	mDNSInterfaceID ImmedAnswer;		// Someone on this interface issued a query we need to answer (all-ones for all interfaces)
1975 #if MDNS_LOG_ANSWER_SUPPRESSION_TIMES
1976 	mDNSs32         ImmedAnswerMarkTime;
1977 #endif
1978 	mDNSInterfaceID ImmedAdditional;	// Hint that we might want to also send this record, just to be helpful
1979 	mDNSInterfaceID SendRNow;			// The interface this query is being sent on right now
1980 	mDNSv4Addr      v4Requester;		// Recent v4 query for this record, or all-ones if more than one recent query
1981 	mDNSv6Addr      v6Requester;		// Recent v6 query for this record, or all-ones if more than one recent query
1982 	AuthRecord     *NextResponse;		// Link to the next element in the chain of responses to generate
1983 	const mDNSu8   *NR_AnswerTo;		// Set if this record was selected by virtue of being a direct answer to a question
1984 	AuthRecord     *NR_AdditionalTo;	// Set if this record was selected by virtue of being additional to another
1985 	mDNSs32         ThisAPInterval;		// In platform time units: Current interval for announce/probe
1986 	mDNSs32         LastAPTime;			// In platform time units: Last time we sent announcement/probe
1987 	mDNSs32         LastMCTime;			// Last time we multicast this record (used to guard against packet-storm attacks)
1988 	mDNSInterfaceID LastMCInterface;	// Interface this record was multicast on at the time LastMCTime was recorded
1989 	RData          *NewRData;			// Set if we are updating this record with new rdata
1990 	mDNSu16         newrdlength;		// ... and the length of the new RData
1991 	mDNSRecordUpdateCallback *UpdateCallback;
1992 	mDNSu32         UpdateCredits;		// Token-bucket rate limiting of excessive updates
1993 	mDNSs32         NextUpdateCredit;	// Time next token is added to bucket
1994 	mDNSs32         UpdateBlocked;		// Set if update delaying is in effect
1995 
1996 	// Field Group 4: Transient uDNS state for Authoritative Records
1997 	regState_t   state;			// Maybe combine this with resrec.RecordType state? Right now it's ambiguous and confusing.
1998 								// e.g. rr->resrec.RecordType can be kDNSRecordTypeUnregistered,
1999 								// and rr->state can be regState_Unregistered
2000 								// What if we find one of those statements is true and the other false? What does that mean?
2001 	mDNSBool     uselease;		// dynamic update contains (should contain) lease option
2002 	mDNSs32      expire;		// In platform time units: expiration of lease (-1 for static)
2003 	mDNSBool     Private;		// If zone is private, DNS updates may have to be encrypted to prevent eavesdropping
2004 	mDNSOpaque16 updateid;		// Identifier to match update request and response -- also used when transferring records to Sleep Proxy
2005 	const domainname *zone;		// the zone that is updated
2006 	mDNSAddr     UpdateServer;	// DNS server that handles updates for this zone
2007 	mDNSIPPort   UpdatePort;	// port on which server accepts dynamic updates
2008 								// !!!KRS not technically correct to cache longer than TTL
2009 								// SDC Perhaps should keep a reference to the relevant SRV record in the cache?
2010 	ZoneData  *nta;
2011 	struct tcpInfo_t *tcp;
2012 
2013 	// uDNS_UpdateRecord support fields
2014 	// Do we really need all these in *addition* to NewRData and newrdlength above?
2015 	mDNSu16 OrigRDLen;		// previously registered, being deleted
2016 	mDNSu16 InFlightRDLen;	// currently being registered
2017 	mDNSu16 QueuedRDLen;	// pending operation (re-transmitting if necessary) THEN register the queued update
2018 	RData *OrigRData;
2019 	RData *InFlightRData;
2020 	RData *QueuedRData;
2021 
2022 	// Field Group 5: Large data objects go at the end
2023 	domainname      namestorage;
2024 	RData           rdatastorage;		// Normally the storage is right here, except for oversized records
2025 	// rdatastorage MUST be the last thing in the structure -- when using oversized AuthRecords, extra bytes
2026 	// are appended after the end of the AuthRecord, logically augmenting the size of the rdatastorage
2027 	// DO NOT ADD ANY MORE FIELDS HERE
2028 	};
2029 
2030 #define AuthRecord_uDNS(R) ((R)->resrec.InterfaceID == mDNSInterface_Any && !(R)->ForceMCast && !IsLocalDomain((R)->resrec.name))
2031 #define Question_uDNS(Q)   ((Q)->InterfaceID == mDNSInterface_Any        && !(Q)->ForceMCast && !IsLocalDomain(&(Q)->qname))
2032 
2033 // Wrapper struct for Auth Records for higher-level code that cannot use the AuthRecord's ->next pointer field
2034 typedef struct ARListElem
2035 	{
2036 	struct ARListElem *next;
2037 	AuthRecord ar;          // Note: Must be last element of structure, to accomodate oversized AuthRecords
2038 	} ARListElem;
2039 
2040 struct CacheGroup_struct				// Header object for a list of CacheRecords with the same name
2041 	{
2042 	CacheGroup     *next;				// Next CacheGroup object in this hash table bucket
2043 	mDNSu32         namehash;			// Name-based (i.e. case insensitive) hash of name
2044 	CacheRecord    *members;			// List of CacheRecords with this same name
2045 	CacheRecord   **rrcache_tail;		// Tail end of that list
2046 	domainname     *name;				// Common name for all CacheRecords in this list
2047 	// Size to here is 20 bytes when compiling 32-bit; 40 bytes when compiling 64-bit
2048 	mDNSu8          namestorage[InlineCacheGroupNameSize];
2049 	};
2050 
2051 struct CacheRecord_struct
2052 	{
2053 	CacheRecord    *next;				// Next in list; first element of structure for efficiency reasons
2054 	ResourceRecord  resrec;				// 36 bytes when compiling for 32-bit; 48 when compiling for 64-bit
2055 
2056 	// Transient state for Cache Records
2057 	CacheRecord    *NextInKAList;		// Link to the next element in the chain of known answers to send
2058 	mDNSs32         TimeRcvd;			// In platform time units
2059 	mDNSs32         DelayDelivery;		// Set if we want to defer delivery of this answer to local clients
2060 	mDNSs32         NextRequiredQuery;	// In platform time units
2061 	mDNSs32         LastUsed;			// In platform time units
2062 	DNSQuestion    *CRActiveQuestion;	// Points to an active question referencing this answer
2063 	mDNSu32         UnansweredQueries;	// Number of times we've issued a query for this record without getting an answer
2064 	mDNSs32         LastUnansweredTime;	// In platform time units; last time we incremented UnansweredQueries
2065 #if ENABLE_MULTI_PACKET_QUERY_SNOOPING
2066 	mDNSu32         MPUnansweredQ;		// Multi-packet query handling: Number of times we've seen a query for this record
2067 	mDNSs32         MPLastUnansweredQT;	// Multi-packet query handling: Last time we incremented MPUnansweredQ
2068 	mDNSu32         MPUnansweredKA;		// Multi-packet query handling: Number of times we've seen this record in a KA list
2069 	mDNSBool        MPExpectingKA;		// Multi-packet query handling: Set when we increment MPUnansweredQ; allows one KA
2070 #endif
2071 	CacheRecord    *NextInCFList;		// Set if this is in the list of records we just received with the cache flush bit set
2072 	// Size to here is 76 bytes when compiling 32-bit; 104 bytes when compiling 64-bit
2073 	RData_small     smallrdatastorage;	// Storage for small records is right here (4 bytes header + 68 bytes data = 72 bytes)
2074 	};
2075 
2076 // Storage sufficient to hold either a CacheGroup header or a CacheRecord
2077 // -- for best efficiency (to avoid wasted unused storage) they should be the same size
2078 typedef union CacheEntity_union CacheEntity;
2079 union CacheEntity_union { CacheEntity *next; CacheGroup cg; CacheRecord cr; };
2080 
2081 typedef struct
2082 	{
2083 	CacheRecord r;
2084 	mDNSu8 _extradata[MaximumRDSize-InlineCacheRDSize];		// Glue on the necessary number of extra bytes
2085 	domainname namestorage;									// Needs to go *after* the extra rdata bytes
2086 	} LargeCacheRecord;
2087 
2088 typedef struct HostnameInfo
2089 	{
2090 	struct HostnameInfo *next;
2091 	NATTraversalInfo natinfo;
2092 	domainname fqdn;
2093 	AuthRecord arv4;                          // registered IPv4 address record
2094 	AuthRecord arv6;                          // registered IPv6 address record
2095 	mDNSRecordCallback *StatusCallback;       // callback to deliver success or error code to client layer
2096 	const void *StatusContext;                // Client Context
2097 	} HostnameInfo;
2098 
2099 enum
2100 	{
2101 	DNSServer_Untested = 0,
2102 	DNSServer_Passed   = 1,
2103 	DNSServer_Failed   = 2,
2104 	DNSServer_Disabled = 3
2105 	};
2106 
2107 enum
2108 	{
2109 	DNSServer_FlagDelete = 1,
2110 	DNSServer_FlagNew    = 2
2111 	};
2112 
2113 typedef struct DNSServer
2114 	{
2115 	struct DNSServer *next;
2116 	mDNSInterfaceID interface;	// For specialized uses; we can have DNS servers reachable over specific interfaces
2117 	mDNSAddr        addr;
2118 	mDNSIPPort      port;
2119 	mDNSOpaque16    testid;
2120 	mDNSu32         flags;		// Set when we're planning to delete this from the list
2121 	mDNSu32         teststate;	// Have we sent bug-detection query to this server?
2122 	mDNSs32         lasttest;	// Time we sent last bug-detection query to this server
2123 	domainname      domain;		// name->server matching for "split dns"
2124 	} DNSServer;
2125 
2126 typedef struct ExtraResourceRecord_struct ExtraResourceRecord;
2127 struct ExtraResourceRecord_struct
2128 	{
2129 	ExtraResourceRecord *next;
2130 	mDNSu32 ClientID;  // Opaque ID field to be used by client to map an AddRecord call to a set of Extra records
2131 	AuthRecord r;
2132 	// Note: Add any additional fields *before* the AuthRecord in this structure, not at the end.
2133 	// In some cases clients can allocate larger chunks of memory and set r->rdata->MaxRDLength to indicate
2134 	// that this extra memory is available, which would result in any fields after the AuthRecord getting smashed
2135 	};
2136 
2137 // Note: Within an mDNSServiceCallback mDNS all API calls are legal except mDNS_Init(), mDNS_Exit(), mDNS_Execute()
2138 typedef void mDNSServiceCallback(mDNS *const m, ServiceRecordSet *const sr, mStatus result);
2139 
2140 // A ServiceRecordSet is basically a convenience structure to group together
2141 // the PTR/SRV/TXT records that make up a standard service registration
2142 // It contains its own ServiceCallback+ServiceContext to report aggregate results up to the next layer of software above
2143 // It also contains:
2144 //  * the "_services" PTR record for service enumeration
2145 //  * the optional target host name (for proxy registrations)
2146 //  * the optional list of SubType PTR records
2147 //  * the optional list of additional records attached to the service set (e.g. iChat pictures)
2148 //
2149 // ... and a bunch of stuff related to uDNS, some of which could be simplified or eliminated
2150 
2151 struct ServiceRecordSet_struct
2152 	{
2153 	// These internal state fields are used internally by mDNSCore; the client layer needn't be concerned with them.
2154 	// No fields need to be set up by the client prior to calling mDNS_RegisterService();
2155 	// all required data is passed as parameters to that function.
2156 
2157 	// Begin uDNS info ****************
2158 	// All of these fields should be eliminated
2159 
2160 	// Note: The current uDNS code keeps an explicit list of registered services, and handles them
2161 	// differently to how individual records are treated (this is probably a mistake). What this means is
2162 	// that ServiceRecordSets for uDNS are kept in a linked list, whereas ServiceRecordSets for mDNS exist
2163 	// just as a convenient placeholder to group the component records together and are not kept on any list.
2164 	ServiceRecordSet *uDNS_next;
2165 	regState_t        state;
2166 	mDNSBool          srs_uselease;				// dynamic update contains (should contain) lease option
2167 	mDNSBool          TestForSelfConflict;		// on name conflict, check if we're just seeing our own orphaned records
2168 	mDNSBool          Private;					// If zone is private, DNS updates may have to be encrypted to prevent eavesdropping
2169 	ZoneData         *srs_nta;
2170 	mDNSOpaque16      id;
2171 	domainname        zone;						// the zone that is updated
2172 	mDNSAddr          SRSUpdateServer;			// primary name server for the record's zone  !!!KRS not technically correct to cache longer than TTL
2173 	mDNSIPPort        SRSUpdatePort;			// port on which server accepts dynamic updates
2174 	NATTraversalInfo  NATinfo;
2175 	mDNSBool          ClientCallbackDeferred;	// invoke client callback on completion of pending operation(s)
2176 	mStatus           DeferredStatus;			// status to deliver when above flag is set
2177 	mDNSBool          SRVUpdateDeferred;		// do we need to change target or port once current operation completes?
2178 	mDNSBool          SRVChanged;				// temporarily deregistered service because its SRV target or port changed
2179 	struct tcpInfo_t *tcp;
2180 
2181 	// End uDNS info ****************
2182 
2183 	mDNSServiceCallback *ServiceCallback;
2184 	void                *ServiceContext;
2185 	mDNSBool             Conflict;	// Set if this record set was forcibly deregistered because of a conflict
2186 
2187 	ExtraResourceRecord *Extras;	// Optional list of extra AuthRecords attached to this service registration
2188 	mDNSu32              NumSubTypes;
2189 	AuthRecord          *SubTypes;
2190 	AuthRecord           RR_ADV;	// e.g. _services._dns-sd._udp.local. PTR _printer._tcp.local.
2191 	AuthRecord           RR_PTR;	// e.g. _printer._tcp.local.        PTR Name._printer._tcp.local.
2192 	AuthRecord           RR_SRV;	// e.g. Name._printer._tcp.local.   SRV 0 0 port target
2193 	AuthRecord           RR_TXT;	// e.g. Name._printer._tcp.local.   TXT PrintQueueName
2194 	// Don't add any fields after AuthRecord RR_TXT.
2195 	// This is where the implicit extra space goes if we allocate a ServiceRecordSet containing an oversized RR_TXT record
2196 	};
2197 
2198 // ***************************************************************************
2199 #if 0
2200 #pragma mark -
2201 #pragma mark - Question structures
2202 #endif
2203 
2204 // We record the last eight instances of each duplicate query
2205 // This gives us v4/v6 on each of Ethernet/AirPort and Firewire, and two free slots "for future expansion"
2206 // If the host has more active interfaces that this it is not fatal -- duplicate question suppression will degrade gracefully.
2207 // Since we will still remember the last eight, the busiest interfaces will still get the effective duplicate question suppression.
2208 #define DupSuppressInfoSize 8
2209 
2210 typedef struct
2211 	{
2212 	mDNSs32               Time;
2213 	mDNSInterfaceID       InterfaceID;
2214 	mDNSs32               Type;				// v4 or v6?
2215 	} DupSuppressInfo;
2216 
2217 typedef enum
2218 	{
2219 	LLQ_InitialRequest    = 1,
2220 	LLQ_SecondaryRequest  = 2,
2221 	LLQ_Established       = 3,
2222 	LLQ_Poll              = 4
2223 	} LLQ_State;
2224 
2225 // LLQ constants
2226 #define kLLQ_Vers      1
2227 #define kLLQ_DefLease  7200 // 2 hours
2228 #define kLLQ_MAX_TRIES 3    // retry an operation 3 times max
2229 #define kLLQ_INIT_RESEND 2 // resend an un-ack'd packet after 2 seconds, then double for each additional
2230 // LLQ Operation Codes
2231 #define kLLQOp_Setup     1
2232 #define kLLQOp_Refresh   2
2233 #define kLLQOp_Event     3
2234 
2235 // LLQ Errror Codes
2236 enum
2237 	{
2238 	LLQErr_NoError    = 0,
2239 	LLQErr_ServFull   = 1,
2240 	LLQErr_Static     = 2,
2241 	LLQErr_FormErr    = 3,
2242 	LLQErr_NoSuchLLQ  = 4,
2243 	LLQErr_BadVers    = 5,
2244 	LLQErr_UnknownErr = 6
2245 	};
2246 
2247 enum { NoAnswer_Normal = 0, NoAnswer_Suspended = 1, NoAnswer_Fail = 2 };
2248 
2249 #define HMAC_LEN    64
2250 #define HMAC_IPAD   0x36
2251 #define HMAC_OPAD   0x5c
2252 #define MD5_LEN     16
2253 
2254 #define AutoTunnelUnregistered(X) (                                              \
2255 	(X)->AutoTunnelHostRecord.resrec.RecordType == kDNSRecordTypeUnregistered && \
2256 	(X)->AutoTunnelDeviceInfo.resrec.RecordType == kDNSRecordTypeUnregistered && \
2257 	(X)->AutoTunnelService.   resrec.RecordType == kDNSRecordTypeUnregistered    )
2258 
2259 // Internal data structure to maintain authentication information
2260 typedef struct DomainAuthInfo
2261 	{
2262 	struct DomainAuthInfo *next;
2263 	mDNSs32          deltime;				// If we're planning to delete this DomainAuthInfo, the time we want it deleted
2264 	mDNSBool         AutoTunnel;
2265 	AuthRecord       AutoTunnelHostRecord;	// User-visible hostname; used as SRV target for AutoTunnel services
2266 	AuthRecord       AutoTunnelTarget;		// Opaque hostname of tunnel endpoint; used as SRV target for AutoTunnelService record
2267 	AuthRecord       AutoTunnelDeviceInfo;	// Device info of tunnel endpoint
2268 	AuthRecord       AutoTunnelService;		// Service record (possibly NAT-Mapped) of IKE daemon implementing tunnel endpoint
2269 	NATTraversalInfo AutoTunnelNAT;
2270 	domainname       domain;
2271 	domainname       keyname;
2272 	char             b64keydata[32];
2273 	mDNSu8           keydata_ipad[HMAC_LEN];	// padded key for inner hash rounds
2274 	mDNSu8           keydata_opad[HMAC_LEN];	// padded key for outer hash rounds
2275 	} DomainAuthInfo;
2276 
2277 // Note: Within an mDNSQuestionCallback mDNS all API calls are legal except mDNS_Init(), mDNS_Exit(), mDNS_Execute()
2278 typedef enum { QC_rmv = 0, QC_add = 1, QC_addnocache = 2 } QC_result;
2279 typedef void mDNSQuestionCallback(mDNS *const m, DNSQuestion *question, const ResourceRecord *const answer, QC_result AddRecord);
2280 struct DNSQuestion_struct
2281 	{
2282 	// Internal state fields. These are used internally by mDNSCore; the client layer needn't be concerned with them.
2283 	DNSQuestion          *next;
2284 	mDNSu32               qnamehash;
2285 	mDNSs32               DelayAnswering;	// Set if we want to defer answering this question until the cache settles
2286 	mDNSs32               LastQTime;		// Last scheduled transmission of this Q on *all* applicable interfaces
2287 	mDNSs32               ThisQInterval;	// LastQTime + ThisQInterval is the next scheduled transmission of this Q
2288 											// ThisQInterval > 0 for an active question;
2289 											// ThisQInterval = 0 for a suspended question that's still in the list
2290 											// ThisQInterval = -1 for a cancelled question (should not still be in list)
2291 	mDNSs32               ExpectUnicastResp;// Set when we send a query with the kDNSQClass_UnicastResponse bit set
2292 	mDNSs32               LastAnswerPktNum;	// The sequence number of the last response packet containing an answer to this Q
2293 	mDNSu32               RecentAnswerPkts;	// Number of answers since the last time we sent this query
2294 	mDNSu32               CurrentAnswers;	// Number of records currently in the cache that answer this question
2295 	mDNSu32               LargeAnswers;		// Number of answers with rdata > 1024 bytes
2296 	mDNSu32               UniqueAnswers;	// Number of answers received with kDNSClass_UniqueRRSet bit set
2297 	mDNSInterfaceID       FlappingInterface1;// Set when an interface goes away, to flag if remove events are delivered for this Q
2298 	mDNSInterfaceID       FlappingInterface2;// Set when an interface goes away, to flag if remove events are delivered for this Q
2299 	DomainAuthInfo       *AuthInfo;			// Non-NULL if query is currently being done using Private DNS
2300 	DNSQuestion          *DuplicateOf;
2301 	DNSQuestion          *NextInDQList;
2302 	DupSuppressInfo       DupSuppress[DupSuppressInfoSize];
2303 	mDNSInterfaceID       SendQNow;			// The interface this query is being sent on right now
2304 	mDNSBool              SendOnAll;		// Set if we're sending this question on all active interfaces
2305 	mDNSu32               RequestUnicast;	// Non-zero if we want to send query with kDNSQClass_UnicastResponse bit set
2306 	mDNSs32               LastQTxTime;		// Last time this Q was sent on one (but not necessarily all) interfaces
2307 	mDNSu32               CNAMEReferrals;	// Count of how many CNAME redirections we've done
2308 
2309 	// Wide Area fields. These are used internally by the uDNS core
2310 	UDPSocket            *LocalSocket;
2311 	DNSServer            *qDNSServer;		// Caching server for this query (in the absence of an SRV saying otherwise)
2312 	mDNSu8                unansweredQueries;// The number of unanswered queries to this server
2313 
2314 	ZoneData             *nta;				// Used for getting zone data for private or LLQ query
2315 	mDNSAddr              servAddr;			// Address and port learned from _dns-llq, _dns-llq-tls or _dns-query-tls SRV query
2316 	mDNSIPPort            servPort;
2317 	struct tcpInfo_t *tcp;
2318 	mDNSu8                NoAnswer;			// Set if we want to suppress answers until tunnel setup has completed
2319 
2320 	// LLQ-specific fields. These fields are only meaningful when LongLived flag is set
2321 	LLQ_State             state;
2322 	mDNSu32               ReqLease;			// seconds (relative)
2323 	mDNSs32               expire;			// ticks (absolute)
2324 	mDNSs16               ntries;
2325 	mDNSOpaque64          id;
2326 
2327 	// Client API fields: The client must set up these fields *before* calling mDNS_StartQuery()
2328 	mDNSInterfaceID       InterfaceID;		// Non-zero if you want to issue queries only on a single specific IP interface
2329 	mDNSAddr              Target;			// Non-zero if you want to direct queries to a specific unicast target address
2330 	mDNSIPPort            TargetPort;		// Must be set if Target is set
2331 	mDNSOpaque16          TargetQID;		// Must be set if Target is set
2332 	domainname            qname;
2333 	mDNSu16               qtype;
2334 	mDNSu16               qclass;
2335 	mDNSBool              LongLived;        // Set by client for calls to mDNS_StartQuery to indicate LLQs to unicast layer.
2336 	mDNSBool              ExpectUnique;		// Set by client if it's expecting unique RR(s) for this question, not shared RRs
2337 	mDNSBool              ForceMCast;		// Set by client to force mDNS query, even for apparently uDNS names
2338 	mDNSBool              ReturnIntermed;	// Set by client to request callbacks for intermediate CNAME/NXDOMAIN results
2339 	mDNSQuestionCallback *QuestionCallback;
2340 	void                 *QuestionContext;
2341 	};
2342 
2343 typedef struct
2344 	{
2345 	// Client API fields: The client must set up name and InterfaceID *before* calling mDNS_StartResolveService()
2346 	// When the callback is invoked, ip, port, TXTlen and TXTinfo will have been filled in with the results learned from the network.
2347 	domainname      name;
2348 	mDNSInterfaceID InterfaceID;		// ID of the interface the response was received on
2349 	mDNSAddr        ip;					// Remote (destination) IP address where this service can be accessed
2350 	mDNSIPPort      port;				// Port where this service can be accessed
2351 	mDNSu16         TXTlen;
2352 	mDNSu8          TXTinfo[2048];		// Additional demultiplexing information (e.g. LPR queue name)
2353 	} ServiceInfo;
2354 
2355 // Note: Within an mDNSServiceInfoQueryCallback mDNS all API calls are legal except mDNS_Init(), mDNS_Exit(), mDNS_Execute()
2356 typedef struct ServiceInfoQuery_struct ServiceInfoQuery;
2357 typedef void mDNSServiceInfoQueryCallback(mDNS *const m, ServiceInfoQuery *query);
2358 struct ServiceInfoQuery_struct
2359 	{
2360 	// Internal state fields. These are used internally by mDNSCore; the client layer needn't be concerned with them.
2361 	// No fields need to be set up by the client prior to calling mDNS_StartResolveService();
2362 	// all required data is passed as parameters to that function.
2363 	// The ServiceInfoQuery structure memory is working storage for mDNSCore to discover the requested information
2364 	// and place it in the ServiceInfo structure. After the client has called mDNS_StopResolveService(), it may
2365 	// dispose of the ServiceInfoQuery structure while retaining the results in the ServiceInfo structure.
2366 	DNSQuestion                   qSRV;
2367 	DNSQuestion                   qTXT;
2368 	DNSQuestion                   qAv4;
2369 	DNSQuestion                   qAv6;
2370 	mDNSu8                        GotSRV;
2371 	mDNSu8                        GotTXT;
2372 	mDNSu8                        GotADD;
2373 	mDNSu32                       Answers;
2374 	ServiceInfo                  *info;
2375 	mDNSServiceInfoQueryCallback *ServiceInfoQueryCallback;
2376 	void                         *ServiceInfoQueryContext;
2377 	};
2378 
2379 typedef enum { ZoneServiceUpdate, ZoneServiceQuery, ZoneServiceLLQ } ZoneService;
2380 
2381 typedef void ZoneDataCallback(mDNS *const m, mStatus err, const ZoneData *result);
2382 
2383 struct ZoneData_struct
2384 	{
2385 	domainname       ChildName;			// Name for which we're trying to find the responsible server
2386 	ZoneService      ZoneService;		// Which service we're seeking for this zone (update, query, or LLQ)
2387 	domainname       *CurrentSOA;		// Points to somewhere within ChildName
2388 	domainname       ZoneName;			// Discovered result: Left-hand-side of SOA record
2389 	mDNSu16          ZoneClass;			// Discovered result: DNS Class from SOA record
2390 	domainname       Host;				// Discovered result: Target host from SRV record
2391 	mDNSIPPort       Port;				// Discovered result: Update port, query port, or LLQ port from SRV record
2392 	mDNSAddr         Addr;				// Discovered result: Address of Target host from SRV record
2393 	mDNSBool         ZonePrivate;		// Discovered result: Does zone require encrypted queries?
2394 	ZoneDataCallback *ZoneDataCallback;	// Caller-specified function to be called upon completion
2395 	void             *ZoneDataContext;
2396 	DNSQuestion      question;			// Storage for any active question
2397 	};
2398 
2399 extern ZoneData *StartGetZoneData(mDNS *const m, const domainname *const name, const ZoneService target, ZoneDataCallback callback, void *callbackInfo);
2400 extern void CancelGetZoneData(mDNS *const m, ZoneData *nta);
2401 
2402 typedef struct DNameListElem
2403 	{
2404 	struct DNameListElem *next;
2405 	mDNSu32 uid;
2406 	domainname name;
2407 	} DNameListElem;
2408 
2409 #if APPLE_OSX_mDNSResponder
2410 typedef struct ClientTunnel
2411 	{
2412 	struct ClientTunnel *next;
2413 	domainname dstname;
2414 	mDNSBool   MarkedForDeletion;
2415 	mDNSv6Addr loc_inner;
2416 	mDNSv4Addr loc_outer;
2417 	mDNSv6Addr rmt_inner;
2418 	mDNSv4Addr rmt_outer;
2419 	mDNSIPPort rmt_outer_port;
2420 	DNSQuestion q;
2421 	} ClientTunnel;
2422 #endif
2423 
2424 // ***************************************************************************
2425 #if 0
2426 #pragma mark -
2427 #pragma mark - NetworkInterfaceInfo_struct
2428 #endif
2429 
2430 typedef struct NetworkInterfaceInfo_struct NetworkInterfaceInfo;
2431 
2432 // A NetworkInterfaceInfo_struct serves two purposes:
2433 // 1. It holds the address, PTR and HINFO records to advertise a given IP address on a given physical interface
2434 // 2. It tells mDNSCore which physical interfaces are available; each physical interface has its own unique InterfaceID.
2435 //    Since there may be multiple IP addresses on a single physical interface,
2436 //    there may be multiple NetworkInterfaceInfo_structs with the same InterfaceID.
2437 //    In this case, to avoid sending the same packet n times, when there's more than one
2438 //    struct with the same InterfaceID, mDNSCore picks one member of the set to be the
2439 //    active representative of the set; all others have the 'InterfaceActive' flag unset.
2440 
2441 struct NetworkInterfaceInfo_struct
2442 	{
2443 	// Internal state fields. These are used internally by mDNSCore; the client layer needn't be concerned with them.
2444 	NetworkInterfaceInfo *next;
2445 
2446 	mDNSu8          InterfaceActive;	// Set if interface is sending & receiving packets (see comment above)
2447 	mDNSu8          IPv4Available;		// If InterfaceActive, set if v4 available on this InterfaceID
2448 	mDNSu8          IPv6Available;		// If InterfaceActive, set if v6 available on this InterfaceID
2449 
2450 	DNSQuestion     NetWakeBrowse;
2451 	DNSQuestion     NetWakeResolve[3];	// For fault-tolerance, we try up to three Sleep Proxies
2452 	mDNSAddr        SPSAddr[3];
2453 	mDNSIPPort      SPSPort[3];
2454 	mDNSs32         NextSPSAttempt;		// -1 if we're not currently attempting to register with any Sleep Proxy
2455 	mDNSs32         NextSPSAttemptTime;
2456 
2457 	// Standard AuthRecords that every Responder host should have (one per active IP address)
2458 	AuthRecord RR_A;					// 'A' or 'AAAA' (address) record for our ".local" name
2459 	AuthRecord RR_PTR;					// PTR (reverse lookup) record
2460 	AuthRecord RR_HINFO;
2461 
2462 	// Client API fields: The client must set up these fields *before* calling mDNS_RegisterInterface()
2463 	mDNSInterfaceID InterfaceID;		// Identifies physical interface; MUST NOT be 0, -1, or -2
2464 	mDNSAddr        ip;					// The IPv4 or IPv6 address to advertise
2465 	mDNSAddr        mask;
2466 	mDNSEthAddr     MAC;
2467 	char            ifname[64];			// Windows uses a GUID string for the interface name, which doesn't fit in 16 bytes
2468 	mDNSu8          Advertise;			// False if you are only searching on this interface
2469 	mDNSu8          McastTxRx;			// Send/Receive multicast on this { InterfaceID, address family } ?
2470 	mDNSu8          NetWake;			// Set if Wake-On-Magic-Packet is enabled on this interface
2471 	};
2472 
2473 typedef struct SearchListElem
2474 	{
2475 	struct SearchListElem *next;
2476 	domainname domain;
2477 	int flag;		// -1 means delete, 0 means unchanged, +1 means newly added
2478 	DNSQuestion BrowseQ;
2479 	DNSQuestion DefBrowseQ;
2480 	DNSQuestion AutomaticBrowseQ;
2481 	DNSQuestion RegisterQ;
2482 	DNSQuestion DefRegisterQ;
2483 	ARListElem *AuthRecs;
2484 	} SearchListElem;
2485 
2486 // For domain enumeration and automatic browsing
2487 // This is the user's DNS search list.
2488 // In each of these domains we search for our special pointer records (lb._dns-sd._udp.<domain>, etc.)
2489 // to discover recommended domains for domain enumeration (browse, default browse, registration,
2490 // default registration) and possibly one or more recommended automatic browsing domains.
2491 extern SearchListElem *SearchList;		// This really ought to be part of mDNS_struct -- SC
2492 
2493 // ***************************************************************************
2494 #if 0
2495 #pragma mark -
2496 #pragma mark - Main mDNS object, used to hold all the mDNS state
2497 #endif
2498 
2499 typedef void mDNSCallback(mDNS *const m, mStatus result);
2500 
2501 #define CACHE_HASH_SLOTS 499
2502 
2503 enum
2504 	{
2505 	mDNS_KnownBug_PhantomInterfaces = 1,
2506 	mDNS_KnownBug_LossySyslog       = 2		// <rdar://problem/6561888>
2507 	};
2508 
2509 enum
2510 	{
2511 	SleepState_Awake = 0,
2512 	SleepState_Transferring = 1,
2513 	SleepState_Sleeping = 2
2514 	};
2515 
2516 struct mDNS_struct
2517 	{
2518 	// Internal state fields. These hold the main internal state of mDNSCore;
2519 	// the client layer needn't be concerned with them.
2520 	// No fields need to be set up by the client prior to calling mDNS_Init();
2521 	// all required data is passed as parameters to that function.
2522 
2523 	mDNS_PlatformSupport *p;			// Pointer to platform-specific data of indeterminite size
2524 	mDNSu32  KnownBugs;
2525 	mDNSBool CanReceiveUnicastOn5353;
2526 	mDNSBool AdvertiseLocalAddresses;
2527 	mDNSBool DivertMulticastAdvertisements; // from interfaces that do not advertise local addresses to local-only
2528 	mStatus mDNSPlatformStatus;
2529 	mDNSIPPort UnicastPort4;
2530 	mDNSIPPort UnicastPort6;
2531 	mDNSEthAddr PrimaryMAC;				// Used as unique host ID
2532 	mDNSCallback *MainCallback;
2533 	void         *MainContext;
2534 
2535 	// For debugging: To catch and report locking failures
2536 	mDNSu32 mDNS_busy;					// Incremented between mDNS_Lock/mDNS_Unlock section
2537 	mDNSu32 mDNS_reentrancy;			// Incremented when calling a client callback
2538 	mDNSu8  lock_rrcache;				// For debugging: Set at times when these lists may not be modified
2539 	mDNSu8  lock_Questions;
2540 	mDNSu8  lock_Records;
2541 #ifndef MaxMsg
2542 	#define MaxMsg 160
2543 #endif
2544 	char MsgBuffer[MaxMsg];				// Temp storage used while building error log messages
2545 
2546 	// Task Scheduling variables
2547 	mDNSs32  timenow_adjust;			// Correction applied if we ever discover time went backwards
2548 	mDNSs32  timenow;					// The time that this particular activation of the mDNS code started
2549 	mDNSs32  timenow_last;				// The time the last time we ran
2550 	mDNSs32  NextScheduledEvent;		// Derived from values below
2551 	mDNSs32  ShutdownTime;				// Set when we're shutting down; allows us to skip some unnecessary steps
2552 	mDNSs32  SuppressSending;			// Don't send *any* packets during this time
2553 	mDNSs32  NextCacheCheck;			// Next time to refresh cache record before it expires
2554 	mDNSs32  NextScheduledQuery;		// Next time to send query in its exponential backoff sequence
2555 	mDNSs32  NextScheduledProbe;		// Next time to probe for new authoritative record
2556 	mDNSs32  NextScheduledResponse;		// Next time to send authoritative record(s) in responses
2557 	mDNSs32  NextScheduledNATOp;		// Next time to send NAT-traversal packets
2558 	mDNSs32  NextScheduledSPS;			// Next time to purge expiring Sleep Proxy records
2559 	mDNSs32  RandomQueryDelay;			// For de-synchronization of query packets on the wire
2560 	mDNSu32  RandomReconfirmDelay;		// For de-synchronization of reconfirmation queries on the wire
2561 	mDNSs32  PktNum;					// Unique sequence number assigned to each received packet
2562 	mDNSu8   SleepState;				// Set if we're sleeping
2563 	mDNSu8   SleepSeqNum;				// "Epoch number" of our current period of wakefulness
2564 	mDNSu8   SystemWakeOnLANEnabled;	// Set if we want to register with a Sleep Proxy before going to sleep
2565 	mDNSs32  DelaySleep;				// To inhibit re-sleeping too quickly right after wake
2566 	mDNSs32  SleepLimit;				// Time window to allow deregistrations, etc.,
2567 										// during which underying platform layer should inhibit system sleep
2568 	mDNSs32  NextScheduledSPRetry;		// Time next sleep proxy registration action is required. Only valid if SleepLimit is nonzero.
2569 
2570 	// These fields only required for mDNS Searcher...
2571 	DNSQuestion *Questions;				// List of all registered questions, active and inactive
2572 	DNSQuestion *NewQuestions;			// Fresh questions not yet answered from cache
2573 	DNSQuestion *CurrentQuestion;		// Next question about to be examined in AnswerLocalQuestions()
2574 	DNSQuestion *LocalOnlyQuestions;	// Questions with InterfaceID set to mDNSInterface_LocalOnly
2575 	DNSQuestion *NewLocalOnlyQuestions;	// Fresh local-only questions not yet answered
2576 	mDNSu32 rrcache_size;				// Total number of available cache entries
2577 	mDNSu32 rrcache_totalused;			// Number of cache entries currently occupied
2578 	mDNSu32 rrcache_active;				// Number of cache entries currently occupied by records that answer active questions
2579 	mDNSu32 rrcache_report;
2580 	CacheEntity *rrcache_free;
2581 	CacheGroup *rrcache_hash[CACHE_HASH_SLOTS];
2582 
2583 	// Fields below only required for mDNS Responder...
2584 	domainlabel nicelabel;				// Rich text label encoded using canonically precomposed UTF-8
2585 	domainlabel hostlabel;				// Conforms to RFC 1034 "letter-digit-hyphen" ARPANET host name rules
2586 	domainname  MulticastHostname;		// Fully Qualified "dot-local" Host Name, e.g. "Foo.local."
2587 	UTF8str255  HIHardware;
2588 	UTF8str255  HISoftware;
2589 	AuthRecord  DeviceInfo;
2590 	AuthRecord *ResourceRecords;
2591 	AuthRecord *DuplicateRecords;		// Records currently 'on hold' because they are duplicates of existing records
2592 	AuthRecord *NewLocalRecords;		// Fresh local-only records not yet delivered to local-only questions
2593 	AuthRecord *CurrentRecord;			// Next AuthRecord about to be examined
2594 	NetworkInterfaceInfo *HostInterfaces;
2595 	mDNSs32 ProbeFailTime;
2596 	mDNSu32 NumFailedProbes;
2597 	mDNSs32 SuppressProbes;
2598 
2599 	// Unicast-specific data
2600 	mDNSs32           NextuDNSEvent;		// uDNS next event
2601 	mDNSs32           NextSRVUpdate;        // Time to perform delayed update
2602 	mDNSs32 SuppressStdPort53Queries;       // Wait before allowing the next standard unicast query to the user's configured DNS server
2603 
2604 	ServiceRecordSet *ServiceRegistrations;
2605 	DNSServer        *DNSServers;           // list of DNS servers
2606 
2607 	mDNSAddr          Router;
2608 	mDNSAddr          AdvertisedV4;         // IPv4 address pointed to by hostname
2609 	mDNSAddr          AdvertisedV6;         // IPv6 address pointed to by hostname
2610 
2611 	DomainAuthInfo   *AuthInfoList;         // list of domains requiring authentication for updates
2612 
2613 	DNSQuestion       ReverseMap;           // Reverse-map query to find static hostname for service target
2614 	DNSQuestion       AutomaticBrowseDomainQ;
2615 	domainname        StaticHostname;       // Current answer to reverse-map query
2616 	domainname        FQDN;
2617 	HostnameInfo     *Hostnames;            // List of registered hostnames + hostname metadata
2618 	mDNSv6Addr        AutoTunnelHostAddr;	// IPv6 address advertised for AutoTunnel services on this machine
2619 	mDNSBool          AutoTunnelHostAddrActive;
2620 	domainlabel       AutoTunnelLabel;		// Used to construct hostname for *IPv4* address of tunnel endpoints
2621 
2622 	mDNSBool          RegisterSearchDomains;
2623 
2624 	// NAT-Traversal fields
2625 	NATTraversalInfo  LLQNAT;					// Single shared NAT Traversal to receive inbound LLQ notifications
2626 	NATTraversalInfo *NATTraversals;
2627 	NATTraversalInfo *CurrentNATTraversal;
2628 	mDNSs32           retryIntervalGetAddr;		// delta between time sent and retry
2629 	mDNSs32           retryGetAddr;				// absolute time when we retry
2630 	mDNSv4Addr        ExternalAddress;
2631 
2632 	UDPSocket        *NATMcastRecvskt;			// For receiving NAT-PMP AddrReply multicasts from router on port 5350
2633 	mDNSu32           LastNATupseconds;			// NAT engine uptime in seconds, from most recent NAT packet
2634 	mDNSs32           LastNATReplyLocalTime;	// Local time in ticks when most recent NAT packet was received
2635 	mDNSu16           LastNATMapResultCode;		// Most recent error code for mappings
2636 
2637 	tcpLNTInfo        tcpAddrInfo;				// legacy NAT traversal TCP connection info for external address
2638 	tcpLNTInfo        tcpDeviceInfo;			// legacy NAT traversal TCP connection info for device info
2639 	tcpLNTInfo       *tcpInfoUnmapList;			// list of pending unmap requests
2640 	mDNSInterfaceID   UPnPInterfaceID;
2641 	UDPSocket        *SSDPSocket;               // For SSDP request/response
2642 	mDNSBool          SSDPWANPPPConnection;     // whether we should send the SSDP query for WANIPConnection or WANPPPConnection
2643 	mDNSIPPort        UPnPRouterPort;			// port we send discovery messages to
2644 	mDNSIPPort        UPnPSOAPPort;				// port we send SOAP messages to
2645 	mDNSu8           *UPnPRouterURL;			// router's URL string
2646 	mDNSBool          UPnPWANPPPConnection;     // whether we're using WANIPConnection or WANPPPConnection
2647 	mDNSu8           *UPnPSOAPURL;				// router's SOAP control URL string
2648 	mDNSu8           *UPnPRouterAddressString;	// holds both the router's address and port
2649 	mDNSu8           *UPnPSOAPAddressString;	// holds both address and port for SOAP messages
2650 
2651 	// Sleep Proxy Server fields
2652 	mDNSu8            SPSType;					// 0 = off, 10-99 encodes desirability metric
2653 	mDNSu8            SPSPortability;			// 10-99
2654 	mDNSu8            SPSMarginalPower;			// 10-99
2655 	mDNSu8            SPSTotalPower;			// 10-99
2656 	mDNSu8            SPSState;					// 0 = off, 1 = running, 2 = shutting down, 3 = suspended during sleep
2657 	mDNSInterfaceID   SPSProxyListChanged;
2658 	UDPSocket        *SPSSocket;
2659 	ServiceRecordSet  SPSRecords;
2660 	mDNSQuestionCallback *SPSBrowseCallback;    // So the platform layer can do something useful with SPS browse results
2661 	int               ProxyRecords;				// Total number of records we're holding as proxy
2662 	#define           MAX_PROXY_RECORDS 10000	/* DOS protection: 400 machines at 25 records each */
2663 
2664 #if APPLE_OSX_mDNSResponder
2665 	ClientTunnel     *TunnelClients;
2666 	uuid_t           asl_uuid;					// uuid for ASL logging
2667 #endif
2668 
2669 	// Fixed storage, to avoid creating large objects on the stack
2670 	// The imsg is declared as a union with a pointer type to enforce CPU-appropriate alignment
2671 	union { DNSMessage m; void *p; } imsg;  // Incoming message received from wire
2672 	DNSMessage        omsg;                 // Outgoing message we're building
2673 	LargeCacheRecord  rec;                  // Resource Record extracted from received message
2674 	};
2675 
2676 #define FORALL_CACHERECORDS(SLOT,CG,CR)                           \
2677 	for ((SLOT) = 0; (SLOT) < CACHE_HASH_SLOTS; (SLOT)++)         \
2678 		for ((CG)=m->rrcache_hash[(SLOT)]; (CG); (CG)=(CG)->next) \
2679 			for ((CR) = (CG)->members; (CR); (CR)=(CR)->next)
2680 
2681 // ***************************************************************************
2682 #if 0
2683 #pragma mark -
2684 #pragma mark - Useful Static Constants
2685 #endif
2686 
2687 extern const mDNSIPPort      zeroIPPort;
2688 extern const mDNSv4Addr      zerov4Addr;
2689 extern const mDNSv6Addr      zerov6Addr;
2690 extern const mDNSEthAddr     zeroEthAddr;
2691 extern const mDNSv4Addr      onesIPv4Addr;
2692 extern const mDNSv6Addr      onesIPv6Addr;
2693 extern const mDNSEthAddr     onesEthAddr;
2694 extern const mDNSAddr        zeroAddr;
2695 
2696 extern const OwnerOptData    zeroOwner;
2697 
2698 extern const mDNSInterfaceID mDNSInterface_Any;				// Zero
2699 extern const mDNSInterfaceID mDNSInterface_LocalOnly;		// Special value
2700 extern const mDNSInterfaceID mDNSInterface_Unicast;			// Special value
2701 
2702 extern const mDNSIPPort   DiscardPort;
2703 extern const mDNSIPPort   SSHPort;
2704 extern const mDNSIPPort   UnicastDNSPort;
2705 extern const mDNSIPPort   SSDPPort;
2706 extern const mDNSIPPort   NSIPCPort;
2707 extern const mDNSIPPort   NATPMPAnnouncementPort;
2708 extern const mDNSIPPort   NATPMPPort;
2709 extern const mDNSIPPort   DNSEXTPort;
2710 extern const mDNSIPPort   MulticastDNSPort;
2711 extern const mDNSIPPort   LoopbackIPCPort;
2712 extern const mDNSIPPort   PrivateDNSPort;
2713 
2714 extern const mDNSv4Addr   AllDNSAdminGroup;
2715 extern const mDNSv4Addr   AllSystemsMcast;
2716 extern const mDNSAddr     AllDNSLinkGroup_v4;
2717 extern const mDNSAddr     AllDNSLinkGroup_v6;
2718 
2719 extern const mDNSOpaque16 zeroID;
2720 extern const mDNSOpaque16 onesID;
2721 extern const mDNSOpaque16 QueryFlags;
2722 extern const mDNSOpaque16 uQueryFlags;
2723 extern const mDNSOpaque16 ResponseFlags;
2724 extern const mDNSOpaque16 UpdateReqFlags;
2725 extern const mDNSOpaque16 UpdateRespFlags;
2726 
2727 extern const mDNSOpaque64 zeroOpaque64;
2728 
2729 #define localdomain           (*(const domainname *)"\x5" "local")
2730 #define DeviceInfoName        (*(const domainname *)"\xC" "_device-info" "\x4" "_tcp")
2731 #define SleepProxyServiceType (*(const domainname *)"\xC" "_sleep-proxy" "\x4" "_udp")
2732 
2733 // ***************************************************************************
2734 #if 0
2735 #pragma mark -
2736 #pragma mark - Inline functions
2737 #endif
2738 
2739 #if (defined(_MSC_VER))
2740 	#define mDNSinline static __inline
2741 #elif ((__GNUC__ > 2) || ((__GNUC__ == 2) && (__GNUC_MINOR__ >= 9)))
2742 	#define mDNSinline static inline
2743 #endif
2744 
2745 // If we're not doing inline functions, then this header needs to have the extern declarations
2746 #if !defined(mDNSinline)
2747 extern mDNSs32      NonZeroTime(mDNSs32 t);
2748 extern mDNSu16      mDNSVal16(mDNSOpaque16 x);
2749 extern mDNSOpaque16 mDNSOpaque16fromIntVal(mDNSu16 v);
2750 #endif
2751 
2752 // If we're compiling the particular C file that instantiates our inlines, then we
2753 // define "mDNSinline" (to empty string) so that we generate code in the following section
2754 #if (!defined(mDNSinline) && mDNS_InstantiateInlines)
2755 #define mDNSinline
2756 #endif
2757 
2758 #ifdef mDNSinline
2759 
2760 mDNSinline mDNSs32 NonZeroTime(mDNSs32 t) { if (t) return(t); else return(1); }
2761 
2762 mDNSinline mDNSu16 mDNSVal16(mDNSOpaque16 x) { return((mDNSu16)((mDNSu16)x.b[0] <<  8 | (mDNSu16)x.b[1])); }
2763 
2764 mDNSinline mDNSOpaque16 mDNSOpaque16fromIntVal(mDNSu16 v)
2765 	{
2766 	mDNSOpaque16 x;
2767 	x.b[0] = (mDNSu8)(v >> 8);
2768 	x.b[1] = (mDNSu8)(v & 0xFF);
2769 	return(x);
2770 	}
2771 
2772 #endif
2773 
2774 // ***************************************************************************
2775 #if 0
2776 #pragma mark -
2777 #pragma mark - Main Client Functions
2778 #endif
2779 
2780 // Every client should call mDNS_Init, passing in storage for the mDNS object and the mDNS_PlatformSupport object.
2781 //
2782 // Clients that are only advertising services should use mDNS_Init_NoCache and mDNS_Init_ZeroCacheSize.
2783 // Clients that plan to perform queries (mDNS_StartQuery, mDNS_StartBrowse, mDNS_StartResolveService, etc.)
2784 // need to provide storage for the resource record cache, or the query calls will return 'mStatus_NoCache'.
2785 // The rrcachestorage parameter is the address of memory for the resource record cache, and
2786 // the rrcachesize parameter is the number of entries in the CacheRecord array passed in.
2787 // (i.e. the size of the cache memory needs to be sizeof(CacheRecord) * rrcachesize).
2788 // OS X 10.3 Panther uses an initial cache size of 64 entries, and then mDNSCore sends an
2789 // mStatus_GrowCache message if it needs more.
2790 //
2791 // Most clients should use mDNS_Init_AdvertiseLocalAddresses. This causes mDNSCore to automatically
2792 // create the correct address records for all the hosts interfaces. If you plan to advertise
2793 // services being offered by the local machine, this is almost always what you want.
2794 // There are two cases where you might use mDNS_Init_DontAdvertiseLocalAddresses:
2795 // 1. A client-only device, that browses for services but doesn't advertise any of its own.
2796 // 2. A proxy-registration service, that advertises services being offered by other machines, and takes
2797 //    the appropriate steps to manually create the correct address records for those other machines.
2798 // In principle, a proxy-like registration service could manually create address records for its own machine too,
2799 // but this would be pointless extra effort when using mDNS_Init_AdvertiseLocalAddresses does that for you.
2800 //
2801 // Note that a client-only device that wishes to prohibit multicast advertisements (e.g. from
2802 // higher-layer API calls) must also set DivertMulticastAdvertisements in the mDNS structure and
2803 // advertise local address(es) on a loopback interface.
2804 //
2805 // When mDNS has finished setting up the client's callback is called
2806 // A client can also spin and poll the mDNSPlatformStatus field to see when it changes from mStatus_Waiting to mStatus_NoError
2807 //
2808 // Call mDNS_StartExit to tidy up before exiting
2809 // Because exiting may be an asynchronous process (e.g. if unicast records need to be deregistered)
2810 // client layer may choose to wait until mDNS_ExitNow() returns true before calling mDNS_FinalExit().
2811 //
2812 // Call mDNS_Register with a completed AuthRecord object to register a resource record
2813 // If the resource record type is kDNSRecordTypeUnique (or kDNSknownunique) then if a conflicting resource record is discovered,
2814 // the resource record's mDNSRecordCallback will be called with error code mStatus_NameConflict. The callback should deregister
2815 // the record, and may then try registering the record again after picking a new name (e.g. by automatically appending a number).
2816 // Following deregistration, the RecordCallback will be called with result mStatus_MemFree to signal that it is safe to deallocate
2817 // the record's storage (memory must be freed asynchronously to allow for goodbye packets and dynamic update deregistration).
2818 //
2819 // Call mDNS_StartQuery to initiate a query. mDNS will proceed to issue Multicast DNS query packets, and any time a response
2820 // is received containing a record which matches the question, the DNSQuestion's mDNSAnswerCallback function will be called
2821 // Call mDNS_StopQuery when no more answers are required
2822 //
2823 // Care should be taken on multi-threaded or interrupt-driven environments.
2824 // The main mDNS routines call mDNSPlatformLock() on entry and mDNSPlatformUnlock() on exit;
2825 // each platform layer needs to implement these appropriately for its respective platform.
2826 // For example, if the support code on a particular platform implements timer callbacks at interrupt time, then
2827 // mDNSPlatformLock/Unlock need to disable interrupts or do similar concurrency control to ensure that the mDNS
2828 // code is not entered by an interrupt-time timer callback while in the middle of processing a client call.
2829 
2830 extern mStatus mDNS_Init      (mDNS *const m, mDNS_PlatformSupport *const p,
2831 								CacheEntity *rrcachestorage, mDNSu32 rrcachesize,
2832 								mDNSBool AdvertiseLocalAddresses,
2833 								mDNSCallback *Callback, void *Context);
2834 // See notes above on use of NoCache/ZeroCacheSize
2835 #define mDNS_Init_NoCache                     mDNSNULL
2836 #define mDNS_Init_ZeroCacheSize               0
2837 // See notes above on use of Advertise/DontAdvertiseLocalAddresses
2838 #define mDNS_Init_AdvertiseLocalAddresses     mDNStrue
2839 #define mDNS_Init_DontAdvertiseLocalAddresses mDNSfalse
2840 #define mDNS_Init_NoInitCallback              mDNSNULL
2841 #define mDNS_Init_NoInitCallbackContext       mDNSNULL
2842 
2843 extern void    mDNS_ConfigChanged(mDNS *const m);
2844 extern void    mDNS_GrowCache (mDNS *const m, CacheEntity *storage, mDNSu32 numrecords);
2845 extern void    mDNS_StartExit (mDNS *const m);
2846 extern void    mDNS_FinalExit (mDNS *const m);
2847 #define mDNS_Close(m) do { mDNS_StartExit(m); mDNS_FinalExit(m); } while(0)
2848 #define mDNS_ExitNow(m, now) ((now) - (m)->ShutdownTime >= 0 || (!(m)->ResourceRecords && !(m)->ServiceRegistrations))
2849 
2850 extern mDNSs32 mDNS_Execute   (mDNS *const m);
2851 
2852 extern mStatus mDNS_Register  (mDNS *const m, AuthRecord *const rr);
2853 extern mStatus mDNS_Update    (mDNS *const m, AuthRecord *const rr, mDNSu32 newttl,
2854 								const mDNSu16 newrdlength, RData *const newrdata, mDNSRecordUpdateCallback *Callback);
2855 extern mStatus mDNS_Deregister(mDNS *const m, AuthRecord *const rr);
2856 
2857 extern mStatus mDNS_StartQuery(mDNS *const m, DNSQuestion *const question);
2858 extern mStatus mDNS_StopQuery (mDNS *const m, DNSQuestion *const question);
2859 extern mStatus mDNS_StopQueryWithRemoves(mDNS *const m, DNSQuestion *const question);
2860 extern mStatus mDNS_Reconfirm (mDNS *const m, CacheRecord *const cacherr);
2861 extern mStatus mDNS_ReconfirmByValue(mDNS *const m, ResourceRecord *const rr);
2862 extern void    mDNS_PurgeCacheResourceRecord(mDNS *const m, CacheRecord *rr);
2863 extern mDNSs32 mDNS_TimeNow(const mDNS *const m);
2864 
2865 extern mStatus mDNS_StartNATOperation(mDNS *const m, NATTraversalInfo *traversal);
2866 extern mStatus mDNS_StopNATOperation(mDNS *const m, NATTraversalInfo *traversal);
2867 extern mStatus mDNS_StopNATOperation_internal(mDNS *m, NATTraversalInfo *traversal);
2868 
2869 extern DomainAuthInfo *GetAuthInfoForName(mDNS *m, const domainname *const name);
2870 
2871 // ***************************************************************************
2872 #if 0
2873 #pragma mark -
2874 #pragma mark - Platform support functions that are accessible to the client layer too
2875 #endif
2876 
2877 extern mDNSs32  mDNSPlatformOneSecond;
2878 
2879 // ***************************************************************************
2880 #if 0
2881 #pragma mark -
2882 #pragma mark - General utility and helper functions
2883 #endif
2884 
2885 // mDNS_RegisterService is a single call to register the set of resource records associated with a given named service.
2886 //
2887 // mDNS_StartResolveService is single call which is equivalent to multiple calls to mDNS_StartQuery,
2888 // to find the IP address, port number, and demultiplexing information for a given named service.
2889 // As with mDNS_StartQuery, it executes asynchronously, and calls the ServiceInfoQueryCallback when the answer is
2890 // found. After the service is resolved, the client should call mDNS_StopResolveService to complete the transaction.
2891 // The client can also call mDNS_StopResolveService at any time to abort the transaction.
2892 //
2893 // mDNS_AddRecordToService adds an additional record to a Service Record Set.  This record may be deregistered
2894 // via mDNS_RemoveRecordFromService, or by deregistering the service.  mDNS_RemoveRecordFromService is passed a
2895 // callback to free the memory associated with the extra RR when it is safe to do so.  The ExtraResourceRecord
2896 // object can be found in the record's context pointer.
2897 
2898 // mDNS_GetBrowseDomains is a special case of the mDNS_StartQuery call, where the resulting answers
2899 // are a list of PTR records indicating (in the rdata) domains that are recommended for browsing.
2900 // After getting the list of domains to browse, call mDNS_StopQuery to end the search.
2901 // mDNS_GetDefaultBrowseDomain returns the name of the domain that should be highlighted by default.
2902 //
2903 // mDNS_GetRegistrationDomains and mDNS_GetDefaultRegistrationDomain are the equivalent calls to get the list
2904 // of one or more domains that should be offered to the user as choices for where they may register their service,
2905 // and the default domain in which to register in the case where the user has made no selection.
2906 
2907 extern void    mDNS_SetupResourceRecord(AuthRecord *rr, RData *RDataStorage, mDNSInterfaceID InterfaceID,
2908                mDNSu16 rrtype, mDNSu32 ttl, mDNSu8 RecordType, mDNSRecordCallback Callback, void *Context);
2909 
2910 extern mStatus mDNS_RegisterService  (mDNS *const m, ServiceRecordSet *sr,
2911                const domainlabel *const name, const domainname *const type, const domainname *const domain,
2912                const domainname *const host, mDNSIPPort port, const mDNSu8 txtinfo[], mDNSu16 txtlen,
2913                AuthRecord *SubTypes, mDNSu32 NumSubTypes,
2914                const mDNSInterfaceID InterfaceID, mDNSServiceCallback Callback, void *Context);
2915 extern mStatus mDNS_AddRecordToService(mDNS *const m, ServiceRecordSet *sr, ExtraResourceRecord *extra, RData *rdata, mDNSu32 ttl);
2916 extern mStatus mDNS_RemoveRecordFromService(mDNS *const m, ServiceRecordSet *sr, ExtraResourceRecord *extra, mDNSRecordCallback MemFreeCallback, void *Context);
2917 extern mStatus mDNS_RenameAndReregisterService(mDNS *const m, ServiceRecordSet *const sr, const domainlabel *newname);
2918 extern mStatus mDNS_DeregisterService(mDNS *const m, ServiceRecordSet *sr);
2919 
2920 extern mStatus mDNS_RegisterNoSuchService(mDNS *const m, AuthRecord *const rr,
2921                const domainlabel *const name, const domainname *const type, const domainname *const domain,
2922                const domainname *const host,
2923                const mDNSInterfaceID InterfaceID, mDNSRecordCallback Callback, void *Context);
2924 #define        mDNS_DeregisterNoSuchService mDNS_Deregister
2925 
2926 extern void mDNS_SetupQuestion(DNSQuestion *const q, const mDNSInterfaceID InterfaceID, const domainname *const name,
2927                const mDNSu16 qtype, mDNSQuestionCallback *const callback, void *const context);
2928 
2929 extern mStatus mDNS_StartBrowse(mDNS *const m, DNSQuestion *const question,
2930                const domainname *const srv, const domainname *const domain,
2931                const mDNSInterfaceID InterfaceID, mDNSBool ForceMCast, mDNSQuestionCallback *Callback, void *Context);
2932 #define        mDNS_StopBrowse mDNS_StopQuery
2933 
2934 extern mStatus mDNS_StartResolveService(mDNS *const m, ServiceInfoQuery *query, ServiceInfo *info, mDNSServiceInfoQueryCallback *Callback, void *Context);
2935 extern void    mDNS_StopResolveService (mDNS *const m, ServiceInfoQuery *query);
2936 
2937 typedef enum
2938 	{
2939 	mDNS_DomainTypeBrowse              = 0,
2940 	mDNS_DomainTypeBrowseDefault       = 1,
2941 	mDNS_DomainTypeBrowseAutomatic     = 2,
2942 	mDNS_DomainTypeRegistration        = 3,
2943 	mDNS_DomainTypeRegistrationDefault = 4,
2944 
2945 	mDNS_DomainTypeMax = 4
2946 	} mDNS_DomainType;
2947 
2948 extern const char *const mDNS_DomainTypeNames[];
2949 
2950 extern mStatus mDNS_GetDomains(mDNS *const m, DNSQuestion *const question, mDNS_DomainType DomainType, const domainname *dom,
2951 								const mDNSInterfaceID InterfaceID, mDNSQuestionCallback *Callback, void *Context);
2952 #define        mDNS_StopGetDomains mDNS_StopQuery
2953 extern mStatus mDNS_AdvertiseDomains(mDNS *const m, AuthRecord *rr, mDNS_DomainType DomainType, const mDNSInterfaceID InterfaceID, char *domname);
2954 #define        mDNS_StopAdvertiseDomains mDNS_Deregister
2955 
2956 extern mDNSOpaque16 mDNS_NewMessageID(mDNS *const m);
2957 
2958 extern DNSServer *GetServerForName(mDNS *m, const domainname *name);
2959 
2960 // ***************************************************************************
2961 #if 0
2962 #pragma mark -
2963 #pragma mark - DNS name utility functions
2964 #endif
2965 
2966 // In order to expose the full capabilities of the DNS protocol (which allows any arbitrary eight-bit values
2967 // in domain name labels, including unlikely characters like ascii nulls and even dots) all the mDNS APIs
2968 // work with DNS's native length-prefixed strings. For convenience in C, the following utility functions
2969 // are provided for converting between C's null-terminated strings and DNS's length-prefixed strings.
2970 
2971 // Assignment
2972 // A simple C structure assignment of a domainname can cause a protection fault by accessing unmapped memory,
2973 // because that object is defined to be 256 bytes long, but not all domainname objects are truly the full size.
2974 // This macro uses mDNSPlatformMemCopy() to make sure it only touches the actual bytes that are valid.
2975 #define AssignDomainName(DST, SRC) do { mDNSu16 len__ = DomainNameLength((SRC)); \
2976 	if (len__ <= MAX_DOMAIN_NAME) mDNSPlatformMemCopy((DST)->c, (SRC)->c, len__); else (DST)->c[0] = 0; } while(0)
2977 
2978 // Comparison functions
2979 #define SameDomainLabelCS(A,B) ((A)[0] == (B)[0] && mDNSPlatformMemSame((A)+1, (B)+1, (A)[0]))
2980 extern mDNSBool SameDomainLabel(const mDNSu8 *a, const mDNSu8 *b);
2981 extern mDNSBool SameDomainName(const domainname *const d1, const domainname *const d2);
2982 extern mDNSBool SameDomainNameCS(const domainname *const d1, const domainname *const d2);
2983 extern mDNSBool IsLocalDomain(const domainname *d);     // returns true for domains that by default should be looked up using link-local multicast
2984 
2985 #define FirstLabel(X)  ((const domainlabel *)(X))
2986 #define SecondLabel(X) ((const domainlabel *)&(X)->c[1 + (X)->c[0]])
2987 extern const mDNSu8 *LastLabel(const domainname *d);
2988 
2989 // Get total length of domain name, in native DNS format, including terminal root label
2990 //   (e.g. length of "com." is 5 (length byte, three data bytes, final zero)
2991 extern mDNSu16  DomainNameLengthLimit(const domainname *const name, const mDNSu8 *limit);
2992 #define DomainNameLength(name) DomainNameLengthLimit((name), (name)->c + MAX_DOMAIN_NAME)
2993 
2994 // Append functions to append one or more labels to an existing native format domain name:
2995 //   AppendLiteralLabelString adds a single label from a literal C string, with no escape character interpretation.
2996 //   AppendDNSNameString      adds zero or more labels from a C string using conventional DNS dots-and-escaping interpretation
2997 //   AppendDomainLabel        adds a single label from a native format domainlabel
2998 //   AppendDomainName         adds zero or more labels from a native format domainname
2999 extern mDNSu8  *AppendLiteralLabelString(domainname *const name, const char *cstr);
3000 extern mDNSu8  *AppendDNSNameString     (domainname *const name, const char *cstr);
3001 extern mDNSu8  *AppendDomainLabel       (domainname *const name, const domainlabel *const label);
3002 extern mDNSu8  *AppendDomainName        (domainname *const name, const domainname *const append);
3003 
3004 // Convert from null-terminated string to native DNS format:
3005 //   The DomainLabel form makes a single label from a literal C string, with no escape character interpretation.
3006 //   The DomainName form makes native format domain name from a C string using conventional DNS interpretation:
3007 //     dots separate labels, and within each label, '\.' represents a literal dot, '\\' represents a literal
3008 //     backslash and backslash with three decimal digits (e.g. \000) represents an arbitrary byte value.
3009 extern mDNSBool MakeDomainLabelFromLiteralString(domainlabel *const label, const char *cstr);
3010 extern mDNSu8  *MakeDomainNameFromDNSNameString (domainname  *const name,  const char *cstr);
3011 
3012 // Convert native format domainlabel or domainname back to C string format
3013 // IMPORTANT:
3014 // When using ConvertDomainLabelToCString, the target buffer must be MAX_ESCAPED_DOMAIN_LABEL (254) bytes long
3015 // to guarantee there will be no buffer overrun. It is only safe to use a buffer shorter than this in rare cases
3016 // where the label is known to be constrained somehow (for example, if the label is known to be either "_tcp" or "_udp").
3017 // Similarly, when using ConvertDomainNameToCString, the target buffer must be MAX_ESCAPED_DOMAIN_NAME (1009) bytes long.
3018 // See definitions of MAX_ESCAPED_DOMAIN_LABEL and MAX_ESCAPED_DOMAIN_NAME for more detailed explanation.
3019 extern char    *ConvertDomainLabelToCString_withescape(const domainlabel *const name, char *cstr, char esc);
3020 #define         ConvertDomainLabelToCString_unescaped(D,C) ConvertDomainLabelToCString_withescape((D), (C), 0)
3021 #define         ConvertDomainLabelToCString(D,C)           ConvertDomainLabelToCString_withescape((D), (C), '\\')
3022 extern char    *ConvertDomainNameToCString_withescape(const domainname *const name, char *cstr, char esc);
3023 #define         ConvertDomainNameToCString_unescaped(D,C) ConvertDomainNameToCString_withescape((D), (C), 0)
3024 #define         ConvertDomainNameToCString(D,C)           ConvertDomainNameToCString_withescape((D), (C), '\\')
3025 
3026 extern void     ConvertUTF8PstringToRFC1034HostLabel(const mDNSu8 UTF8Name[], domainlabel *const hostlabel);
3027 
3028 extern mDNSu8  *ConstructServiceName(domainname *const fqdn, const domainlabel *name, const domainname *type, const domainname *const domain);
3029 extern mDNSBool DeconstructServiceName(const domainname *const fqdn, domainlabel *const name, domainname *const type, domainname *const domain);
3030 
3031 // Note: Some old functions have been replaced by more sensibly-named versions.
3032 // You can uncomment the hash-defines below if you don't want to have to change your source code right away.
3033 // When updating your code, note that (unlike the old versions) *all* the new routines take the target object
3034 // as their first parameter.
3035 //#define ConvertCStringToDomainName(SRC,DST)  MakeDomainNameFromDNSNameString((DST),(SRC))
3036 //#define ConvertCStringToDomainLabel(SRC,DST) MakeDomainLabelFromLiteralString((DST),(SRC))
3037 //#define AppendStringLabelToName(DST,SRC)     AppendLiteralLabelString((DST),(SRC))
3038 //#define AppendStringNameToName(DST,SRC)      AppendDNSNameString((DST),(SRC))
3039 //#define AppendDomainLabelToName(DST,SRC)     AppendDomainLabel((DST),(SRC))
3040 //#define AppendDomainNameToName(DST,SRC)      AppendDomainName((DST),(SRC))
3041 
3042 // ***************************************************************************
3043 #if 0
3044 #pragma mark -
3045 #pragma mark - Other utility functions and macros
3046 #endif
3047 
3048 // mDNS_vsnprintf/snprintf return the number of characters written, excluding the final terminating null.
3049 // The output is always null-terminated: for example, if the output turns out to be exactly buflen long,
3050 // then the output will be truncated by one character to allow space for the terminating null.
3051 // Unlike standard C vsnprintf/snprintf, they return the number of characters *actually* written,
3052 // not the number of characters that *would* have been printed were buflen unlimited.
3053 extern mDNSu32 mDNS_vsnprintf(char *sbuffer, mDNSu32 buflen, const char *fmt, va_list arg);
3054 extern mDNSu32 mDNS_snprintf(char *sbuffer, mDNSu32 buflen, const char *fmt, ...) IS_A_PRINTF_STYLE_FUNCTION(3,4);
3055 extern mDNSu32 NumCacheRecordsForInterfaceID(const mDNS *const m, mDNSInterfaceID id);
3056 extern char *DNSTypeName(mDNSu16 rrtype);
3057 extern char *GetRRDisplayString_rdb(const ResourceRecord *const rr, const RDataBody *const rd1, char *const buffer);
3058 #define RRDisplayString(m, rr) GetRRDisplayString_rdb(rr, &(rr)->rdata->u, (m)->MsgBuffer)
3059 #define ARDisplayString(m, rr) GetRRDisplayString_rdb(&(rr)->resrec, &(rr)->resrec.rdata->u, (m)->MsgBuffer)
3060 #define CRDisplayString(m, rr) GetRRDisplayString_rdb(&(rr)->resrec, &(rr)->resrec.rdata->u, (m)->MsgBuffer)
3061 extern mDNSBool mDNSSameAddress(const mDNSAddr *ip1, const mDNSAddr *ip2);
3062 extern void IncrementLabelSuffix(domainlabel *name, mDNSBool RichText);
3063 extern mDNSBool mDNSv4AddrIsRFC1918(mDNSv4Addr *addr);  // returns true for RFC1918 private addresses
3064 #define mDNSAddrIsRFC1918(X) ((X)->type == mDNSAddrType_IPv4 && mDNSv4AddrIsRFC1918(&(X)->ip.v4))
3065 
3066 #define mDNSSameIPPort(A,B)      ((A).NotAnInteger == (B).NotAnInteger)
3067 #define mDNSSameOpaque16(A,B)    ((A).NotAnInteger == (B).NotAnInteger)
3068 #define mDNSSameOpaque32(A,B)    ((A).NotAnInteger == (B).NotAnInteger)
3069 #define mDNSSameOpaque64(A,B)    ((A)->l[0] == (B)->l[0] && (A)->l[1] == (B)->l[1])
3070 
3071 #define mDNSSameIPv4Address(A,B) ((A).NotAnInteger == (B).NotAnInteger)
3072 #define mDNSSameIPv6Address(A,B) ((A).l[0] == (B).l[0] && (A).l[1] == (B).l[1] && (A).l[2] == (B).l[2] && (A).l[3] == (B).l[3])
3073 #define mDNSSameEthAddress(A,B)  ((A)->w[0] == (B)->w[0] && (A)->w[1] == (B)->w[1] && (A)->w[2] == (B)->w[2])
3074 
3075 #define mDNSIPPortIsZero(A)      ((A).NotAnInteger                            == 0)
3076 #define mDNSOpaque16IsZero(A)    ((A).NotAnInteger                            == 0)
3077 #define mDNSOpaque64IsZero(A)    (((A)->l[0] | (A)->l[1]                    ) == 0)
3078 #define mDNSIPv4AddressIsZero(A) ((A).NotAnInteger                            == 0)
3079 #define mDNSIPv6AddressIsZero(A) (((A).l[0] | (A).l[1] | (A).l[2] | (A).l[3]) == 0)
3080 #define mDNSEthAddressIsZero(A)  (((A).w[0] | (A).w[1] | (A).w[2]           ) == 0)
3081 
3082 #define mDNSIPv4AddressIsOnes(A) ((A).NotAnInteger == 0xFFFFFFFF)
3083 #define mDNSIPv6AddressIsOnes(A) (((A).l[0] & (A).l[1] & (A).l[2] & (A).l[3]) == 0xFFFFFFFF)
3084 
3085 #define mDNSAddressIsAllDNSLinkGroup(X) (                                                            \
3086 	((X)->type == mDNSAddrType_IPv4 && mDNSSameIPv4Address((X)->ip.v4, AllDNSLinkGroup_v4.ip.v4)) || \
3087 	((X)->type == mDNSAddrType_IPv6 && mDNSSameIPv6Address((X)->ip.v6, AllDNSLinkGroup_v6.ip.v6))    )
3088 
3089 #define mDNSAddressIsZero(X) (                                                \
3090 	((X)->type == mDNSAddrType_IPv4 && mDNSIPv4AddressIsZero((X)->ip.v4))  || \
3091 	((X)->type == mDNSAddrType_IPv6 && mDNSIPv6AddressIsZero((X)->ip.v6))     )
3092 
3093 #define mDNSAddressIsValidNonZero(X) (                                        \
3094 	((X)->type == mDNSAddrType_IPv4 && !mDNSIPv4AddressIsZero((X)->ip.v4)) || \
3095 	((X)->type == mDNSAddrType_IPv6 && !mDNSIPv6AddressIsZero((X)->ip.v6))    )
3096 
3097 #define mDNSAddressIsOnes(X) (                                                \
3098 	((X)->type == mDNSAddrType_IPv4 && mDNSIPv4AddressIsOnes((X)->ip.v4))  || \
3099 	((X)->type == mDNSAddrType_IPv6 && mDNSIPv6AddressIsOnes((X)->ip.v6))     )
3100 
3101 #define mDNSAddressIsValid(X) (                                                                                             \
3102 	((X)->type == mDNSAddrType_IPv4) ? !(mDNSIPv4AddressIsZero((X)->ip.v4) || mDNSIPv4AddressIsOnes((X)->ip.v4)) :          \
3103 	((X)->type == mDNSAddrType_IPv6) ? !(mDNSIPv6AddressIsZero((X)->ip.v6) || mDNSIPv6AddressIsOnes((X)->ip.v6)) : mDNSfalse)
3104 
3105 #define mDNSv4AddressIsLinkLocal(X) ((X)->b[0] ==  169 &&  (X)->b[1]         ==  254)
3106 #define mDNSv6AddressIsLinkLocal(X) ((X)->b[0] == 0xFE && ((X)->b[1] & 0xC0) == 0x80)
3107 
3108 #define mDNSAddressIsLinkLocal(X)  (                                                    \
3109 	((X)->type == mDNSAddrType_IPv4) ? mDNSv4AddressIsLinkLocal(&(X)->ip.v4) :          \
3110 	((X)->type == mDNSAddrType_IPv6) ? mDNSv6AddressIsLinkLocal(&(X)->ip.v6) : mDNSfalse)
3111 
3112 // ***************************************************************************
3113 #if 0
3114 #pragma mark -
3115 #pragma mark - Authentication Support
3116 #endif
3117 
3118 // Unicast DNS and Dynamic Update specific Client Calls
3119 //
3120 // mDNS_SetSecretForDomain tells the core to authenticate (via TSIG with an HMAC_MD5 hash of the shared secret)
3121 // when dynamically updating a given zone (and its subdomains).  The key used in authentication must be in
3122 // domain name format.  The shared secret must be a null-terminated base64 encoded string.  A minimum size of
3123 // 16 bytes (128 bits) is recommended for an MD5 hash as per RFC 2485.
3124 // Calling this routine multiple times for a zone replaces previously entered values.  Call with a NULL key
3125 // to dissable authentication for the zone.
3126 
3127 extern mStatus mDNS_SetSecretForDomain(mDNS *m, DomainAuthInfo *info,
3128 	const domainname *domain, const domainname *keyname, const char *b64keydata, mDNSBool AutoTunnel);
3129 
3130 extern void RecreateNATMappings(mDNS *const m);
3131 
3132 // Hostname/Unicast Interface Configuration
3133 
3134 // All hostnames advertised point to one IPv4 address and/or one IPv6 address, set via SetPrimaryInterfaceInfo.  Invoking this routine
3135 // updates all existing hostnames to point to the new address.
3136 
3137 // A hostname is added via AddDynDNSHostName, which points to the primary interface's v4 and/or v6 addresss
3138 
3139 // The status callback is invoked to convey success or failure codes - the callback should not modify the AuthRecord or free memory.
3140 // Added hostnames may be removed (deregistered) via mDNS_RemoveDynDNSHostName.
3141 
3142 // Host domains added prior to specification of the primary interface address and computer name will be deferred until
3143 // these values are initialized.
3144 
3145 // DNS servers used to resolve unicast queries are specified by mDNS_AddDNSServer.
3146 // For "split" DNS configurations, in which queries for different domains are sent to different servers (e.g. VPN and external),
3147 // a domain may be associated with a DNS server.  For standard configurations, specify the root label (".") or NULL.
3148 
3149 extern void mDNS_AddDynDNSHostName(mDNS *m, const domainname *fqdn, mDNSRecordCallback *StatusCallback, const void *StatusContext);
3150 extern void mDNS_RemoveDynDNSHostName(mDNS *m, const domainname *fqdn);
3151 extern void mDNS_SetPrimaryInterfaceInfo(mDNS *m, const mDNSAddr *v4addr,  const mDNSAddr *v6addr, const mDNSAddr *router);
3152 extern DNSServer *mDNS_AddDNSServer(mDNS *const m, const domainname *d, const mDNSInterfaceID interface, const mDNSAddr *addr, const mDNSIPPort port);
3153 extern void PushDNSServerToEnd(mDNS *const m, DNSQuestion *q);
3154 extern void mDNS_AddSearchDomain(const domainname *const domain);
3155 
3156 // We use ((void *)0) here instead of mDNSNULL to avoid compile warnings on gcc 4.2
3157 #define mDNS_AddSearchDomain_CString(X) \
3158 	do { domainname d__; if (((X) != (void*)0) && MakeDomainNameFromDNSNameString(&d__, (X)) && d__.c[0]) mDNS_AddSearchDomain(&d__); } while(0)
3159 
3160 // Routines called by the core, exported by DNSDigest.c
3161 
3162 // Convert an arbitrary base64 encoded key key into an HMAC key (stored in AuthInfo struct)
3163 extern mDNSs32 DNSDigest_ConstructHMACKeyfromBase64(DomainAuthInfo *info, const char *b64key);
3164 
3165 // sign a DNS message.  The message must be complete, with all values in network byte order.  end points to the end
3166 // of the message, and is modified by this routine.  numAdditionals is a pointer to the number of additional
3167 // records in HOST byte order, which is incremented upon successful completion of this routine.  The function returns
3168 // the new end pointer on success, and NULL on failure.
3169 extern void DNSDigest_SignMessage(DNSMessage *msg, mDNSu8 **end, DomainAuthInfo *info, mDNSu16 tcode);
3170 
3171 #define SwapDNSHeaderBytes(M) do { \
3172     (M)->h.numQuestions   = (mDNSu16)((mDNSu8 *)&(M)->h.numQuestions  )[0] << 8 | ((mDNSu8 *)&(M)->h.numQuestions  )[1]; \
3173     (M)->h.numAnswers     = (mDNSu16)((mDNSu8 *)&(M)->h.numAnswers    )[0] << 8 | ((mDNSu8 *)&(M)->h.numAnswers    )[1]; \
3174     (M)->h.numAuthorities = (mDNSu16)((mDNSu8 *)&(M)->h.numAuthorities)[0] << 8 | ((mDNSu8 *)&(M)->h.numAuthorities)[1]; \
3175     (M)->h.numAdditionals = (mDNSu16)((mDNSu8 *)&(M)->h.numAdditionals)[0] << 8 | ((mDNSu8 *)&(M)->h.numAdditionals)[1]; \
3176     } while (0)
3177 
3178 #define DNSDigest_SignMessageHostByteOrder(M,E,INFO) \
3179 	do { SwapDNSHeaderBytes(M); DNSDigest_SignMessage((M), (E), (INFO), 0); SwapDNSHeaderBytes(M); } while (0)
3180 
3181 // verify a DNS message.  The message must be complete, with all values in network byte order.  end points to the
3182 // end of the record.  tsig is a pointer to the resource record that contains the TSIG OPT record.  info is
3183 // the matching key to use for verifying the message.  This function expects that the additionals member
3184 // of the DNS message header has already had one subtracted from it.
3185 extern mDNSBool DNSDigest_VerifyMessage(DNSMessage *msg, mDNSu8 *end, LargeCacheRecord *tsig, DomainAuthInfo *info, mDNSu16 *rcode, mDNSu16 *tcode);
3186 
3187 // ***************************************************************************
3188 #if 0
3189 #pragma mark -
3190 #pragma mark - PlatformSupport interface
3191 #endif
3192 
3193 // This section defines the interface to the Platform Support layer.
3194 // Normal client code should not use any of types defined here, or directly call any of the functions defined here.
3195 // The definitions are placed here because sometimes clients do use these calls indirectly, via other supported client operations.
3196 // For example, AssignDomainName is a macro defined using mDNSPlatformMemCopy()
3197 
3198 // Every platform support module must provide the following functions.
3199 // mDNSPlatformInit() typically opens a communication endpoint, and starts listening for mDNS packets.
3200 // When Setup is complete, the platform support layer calls mDNSCoreInitComplete().
3201 // mDNSPlatformSendUDP() sends one UDP packet
3202 // When a packet is received, the PlatformSupport code calls mDNSCoreReceive()
3203 // mDNSPlatformClose() tidies up on exit
3204 //
3205 // Note: mDNSPlatformMemAllocate/mDNSPlatformMemFree are only required for handling oversized resource records and unicast DNS.
3206 // If your target platform has a well-defined specialized application, and you know that all the records it uses
3207 // are InlineCacheRDSize or less, then you can just make a simple mDNSPlatformMemAllocate() stub that always returns
3208 // NULL. InlineCacheRDSize is a compile-time constant, which is set by default to 68. If you need to handle records
3209 // a little larger than this and you don't want to have to implement run-time allocation and freeing, then you
3210 // can raise the value of this constant to a suitable value (at the expense of increased memory usage).
3211 //
3212 // USE CAUTION WHEN CALLING mDNSPlatformRawTime: The m->timenow_adjust correction factor needs to be added
3213 // Generally speaking:
3214 // Code that's protected by the main mDNS lock should just use the m->timenow value
3215 // Code outside the main mDNS lock should use mDNS_TimeNow(m) to get properly adjusted time
3216 // In certain cases there may be reasons why it's necessary to get the time without taking the lock first
3217 // (e.g. inside the routines that are doing the locking and unlocking, where a call to get the lock would result in a
3218 // recursive loop); in these cases use mDNS_TimeNow_NoLock(m) to get mDNSPlatformRawTime with the proper correction factor added.
3219 //
3220 // mDNSPlatformUTC returns the time, in seconds, since Jan 1st 1970 UTC and is required for generating TSIG records
3221 
3222 extern mStatus  mDNSPlatformInit        (mDNS *const m);
3223 extern void     mDNSPlatformClose       (mDNS *const m);
3224 extern mStatus  mDNSPlatformSendUDP(const mDNS *const m, const void *const msg, const mDNSu8 *const end,
3225 mDNSInterfaceID InterfaceID, UDPSocket *src, const mDNSAddr *dst, mDNSIPPort dstport);
3226 
3227 extern void     mDNSPlatformLock        (const mDNS *const m);
3228 extern void     mDNSPlatformUnlock      (const mDNS *const m);
3229 
3230 extern void     mDNSPlatformStrCopy     (      void *dst, const void *src);
3231 extern mDNSu32  mDNSPlatformStrLen      (                 const void *src);
3232 extern void     mDNSPlatformMemCopy     (      void *dst, const void *src, mDNSu32 len);
3233 extern mDNSBool mDNSPlatformMemSame     (const void *dst, const void *src, mDNSu32 len);
3234 extern void     mDNSPlatformMemZero     (      void *dst,                  mDNSu32 len);
3235 #if APPLE_OSX_mDNSResponder && MACOSX_MDNS_MALLOC_DEBUGGING
3236 #define         mDNSPlatformMemAllocate(X) mallocL(#X, X)
3237 #else
3238 extern void *   mDNSPlatformMemAllocate (mDNSu32 len);
3239 #endif
3240 extern void     mDNSPlatformMemFree     (void *mem);
3241 
3242 // If the platform doesn't have a strong PRNG, we define a naive multiply-and-add based on a seed
3243 // from the platform layer.  Long-term, we should embed an arc4 implementation, but the strength
3244 // will still depend on the randomness of the seed.
3245 #if !defined(_PLATFORM_HAS_STRONG_PRNG_) && (_BUILDING_XCODE_PROJECT_ || defined(_WIN32))
3246 #define _PLATFORM_HAS_STRONG_PRNG_ 1
3247 #endif
3248 #if _PLATFORM_HAS_STRONG_PRNG_
3249 extern mDNSu32  mDNSPlatformRandomNumber(void);
3250 #else
3251 extern mDNSu32  mDNSPlatformRandomSeed  (void);
3252 #endif // _PLATFORM_HAS_STRONG_PRNG_
3253 
3254 extern mStatus  mDNSPlatformTimeInit    (void);
3255 extern mDNSs32  mDNSPlatformRawTime     (void);
3256 extern mDNSs32  mDNSPlatformUTC         (void);
3257 #define mDNS_TimeNow_NoLock(m) (mDNSPlatformRawTime() + (m)->timenow_adjust)
3258 
3259 #if MDNS_DEBUGMSGS
3260 extern void	mDNSPlatformWriteDebugMsg(const char *msg);
3261 #endif
3262 extern void	mDNSPlatformWriteLogMsg(const char *ident, const char *msg, mDNSLogLevel_t loglevel);
3263 
3264 #if APPLE_OSX_mDNSResponder
3265 // Utility function for ASL logging
3266 mDNSexport void mDNSASLLog(uuid_t *uuid, const char *subdomain, const char *result, const char *signature, const char *fmt, ...);
3267 #endif
3268 
3269 // Platform support modules should provide the following functions to map between opaque interface IDs
3270 // and interface indexes in order to support the DNS-SD API. If your target platform does not support
3271 // multiple interfaces and/or does not support the DNS-SD API, these functions can be empty.
3272 extern mDNSInterfaceID mDNSPlatformInterfaceIDfromInterfaceIndex(mDNS *const m, mDNSu32 ifindex);
3273 extern mDNSu32 mDNSPlatformInterfaceIndexfromInterfaceID(mDNS *const m, mDNSInterfaceID id);
3274 
3275 // Every platform support module must provide the following functions if it is to support unicast DNS
3276 // and Dynamic Update.
3277 // All TCP socket operations implemented by the platform layer MUST NOT BLOCK.
3278 // mDNSPlatformTCPConnect initiates a TCP connection with a peer, adding the socket descriptor to the
3279 // main event loop.  The return value indicates whether the connection succeeded, failed, or is pending
3280 // (i.e. the call would block.)  On return, the descriptor parameter is set to point to the connected socket.
3281 // The TCPConnectionCallback is subsequently invoked when the connection
3282 // completes (in which case the ConnectionEstablished parameter is true), or data is available for
3283 // reading on the socket (indicated by the ConnectionEstablished parameter being false.)  If the connection
3284 // asynchronously fails, the TCPConnectionCallback should be invoked as usual, with the error being
3285 // returned in subsequent calls to PlatformReadTCP or PlatformWriteTCP.  (This allows for platforms
3286 // with limited asynchronous error detection capabilities.)  PlatformReadTCP and PlatformWriteTCP must
3287 // return the number of bytes read/written, 0 if the call would block, and -1 if an error.  PlatformReadTCP
3288 // should set the closed argument if the socket has been closed.
3289 // PlatformTCPCloseConnection must close the connection to the peer and remove the descriptor from the
3290 // event loop.  CloseConnectin may be called at any time, including in a ConnectionCallback.
3291 
3292 typedef enum
3293 	{
3294 	kTCPSocketFlags_Zero   = 0,
3295 	kTCPSocketFlags_UseTLS = (1 << 0)
3296 	} TCPSocketFlags;
3297 
3298 typedef void (*TCPConnectionCallback)(TCPSocket *sock, void *context, mDNSBool ConnectionEstablished, mStatus err);
3299 extern TCPSocket *mDNSPlatformTCPSocket(mDNS *const m, TCPSocketFlags flags, mDNSIPPort *port);	// creates a TCP socket
3300 extern TCPSocket *mDNSPlatformTCPAccept(TCPSocketFlags flags, int sd);
3301 extern int        mDNSPlatformTCPGetFD(TCPSocket *sock);
3302 extern mStatus    mDNSPlatformTCPConnect(TCPSocket *sock, const mDNSAddr *dst, mDNSOpaque16 dstport, mDNSInterfaceID InterfaceID,
3303                                          TCPConnectionCallback callback, void *context);
3304 extern void       mDNSPlatformTCPCloseConnection(TCPSocket *sock);
3305 extern long       mDNSPlatformReadTCP(TCPSocket *sock, void *buf, unsigned long buflen, mDNSBool *closed);
3306 extern long       mDNSPlatformWriteTCP(TCPSocket *sock, const char *msg, unsigned long len);
3307 extern UDPSocket *mDNSPlatformUDPSocket(mDNS *const m, const mDNSIPPort requestedport);
3308 extern void       mDNSPlatformUDPClose(UDPSocket *sock);
3309 extern void       mDNSPlatformReceiveBPF_fd(mDNS *const m, int fd);
3310 extern void       mDNSPlatformUpdateProxyList(mDNS *const m, const mDNSInterfaceID InterfaceID);
3311 extern void       mDNSPlatformSendRawPacket(const void *const msg, const mDNSu8 *const end, mDNSInterfaceID InterfaceID);
3312 extern void       mDNSPlatformSetLocalARP(const mDNSv4Addr *const tpa, const mDNSEthAddr *const tha, mDNSInterfaceID InterfaceID);
3313 extern void       mDNSPlatformSourceAddrForDest(mDNSAddr *const src, const mDNSAddr *const dst);
3314 
3315 // mDNSPlatformTLSSetupCerts/mDNSPlatformTLSTearDownCerts used by dnsextd
3316 extern mStatus    mDNSPlatformTLSSetupCerts(void);
3317 extern void       mDNSPlatformTLSTearDownCerts(void);
3318 
3319 // Platforms that support unicast browsing and dynamic update registration for clients who do not specify a domain
3320 // in browse/registration calls must implement these routines to get the "default" browse/registration list.
3321 
3322 extern void       mDNSPlatformSetDNSConfig(mDNS *const m, mDNSBool setservers, mDNSBool setsearch, domainname *const fqdn, DNameListElem **RegDomains, DNameListElem **BrowseDomains);
3323 extern mStatus    mDNSPlatformGetPrimaryInterface(mDNS *const m, mDNSAddr *v4, mDNSAddr *v6, mDNSAddr *router);
3324 extern void       mDNSPlatformDynDNSHostNameStatusChanged(const domainname *const dname, const mStatus status);
3325 
3326 #ifdef _LEGACY_NAT_TRAVERSAL_
3327 // Support for legacy NAT traversal protocols, implemented by the platform layer and callable by the core.
3328 extern void     LNT_SendDiscoveryMsg(mDNS *m);
3329 extern void     LNT_ConfigureRouterInfo(mDNS *m, const mDNSInterfaceID InterfaceID, mDNSu8 *data, mDNSu16 len);
3330 extern mStatus  LNT_GetExternalAddress(mDNS *m);
3331 extern mStatus  LNT_MapPort(mDNS *m, NATTraversalInfo *n);
3332 extern mStatus  LNT_UnmapPort(mDNS *m, NATTraversalInfo *n);
3333 extern void     LNT_ClearState(mDNS *const m);
3334 #endif // _LEGACY_NAT_TRAVERSAL_
3335 
3336 // The core mDNS code provides these functions, for the platform support code to call at appropriate times
3337 //
3338 // mDNS_SetFQDN() is called once on startup (typically from mDNSPlatformInit())
3339 // and then again on each subsequent change of the host name.
3340 //
3341 // mDNS_RegisterInterface() is used by the platform support layer to inform mDNSCore of what
3342 // physical and/or logical interfaces are available for sending and receiving packets.
3343 // Typically it is called on startup for each available interface, but register/deregister may be
3344 // called again later, on multiple occasions, to inform the core of interface configuration changes.
3345 // If set->Advertise is set non-zero, then mDNS_RegisterInterface() also registers the standard
3346 // resource records that should be associated with every publicised IP address/interface:
3347 // -- Name-to-address records (A/AAAA)
3348 // -- Address-to-name records (PTR)
3349 // -- Host information (HINFO)
3350 // IMPORTANT: The specified mDNSInterfaceID MUST NOT be 0, -1, or -2; these values have special meaning
3351 // mDNS_RegisterInterface does not result in the registration of global hostnames via dynamic update -
3352 // see mDNS_SetPrimaryInterfaceInfo, mDNS_AddDynDNSHostName, etc. for this purpose.
3353 // Note that the set may be deallocated immediately after it is deregistered via mDNS_DeegisterInterface.
3354 //
3355 // mDNS_RegisterDNS() is used by the platform support layer to provide the core with the addresses of
3356 // available domain name servers for unicast queries/updates.  RegisterDNS() should be called once for
3357 // each name server, typically at startup, or when a new name server becomes available.  DeregiterDNS()
3358 // must be called whenever a registered name server becomes unavailable.  DeregisterDNSList deregisters
3359 // all registered servers.  mDNS_DNSRegistered() returns true if one or more servers are registered in the core.
3360 //
3361 // mDNSCoreInitComplete() is called when the platform support layer is finished.
3362 // Typically this is at the end of mDNSPlatformInit(), but may be later
3363 // (on platforms like OT that allow asynchronous initialization of the networking stack).
3364 //
3365 // mDNSCoreReceive() is called when a UDP packet is received
3366 //
3367 // mDNSCoreMachineSleep() is called when the machine sleeps or wakes
3368 // (This refers to heavyweight laptop-style sleep/wake that disables network access,
3369 // not lightweight second-by-second CPU power management modes.)
3370 
3371 extern void     mDNS_SetFQDN(mDNS *const m);
3372 extern void     mDNS_ActivateNetWake_internal  (mDNS *const m, NetworkInterfaceInfo *set);
3373 extern void     mDNS_DeactivateNetWake_internal(mDNS *const m, NetworkInterfaceInfo *set);
3374 extern mStatus  mDNS_RegisterInterface  (mDNS *const m, NetworkInterfaceInfo *set, mDNSBool flapping);
3375 extern void     mDNS_DeregisterInterface(mDNS *const m, NetworkInterfaceInfo *set, mDNSBool flapping);
3376 extern void     mDNSCoreInitComplete(mDNS *const m, mStatus result);
3377 extern void     mDNSCoreReceive(mDNS *const m, void *const msg, const mDNSu8 *const end,
3378 								const mDNSAddr *const srcaddr, const mDNSIPPort srcport,
3379 								const mDNSAddr *const dstaddr, const mDNSIPPort dstport, const mDNSInterfaceID InterfaceID);
3380 extern void 	mDNSCoreRestartQueries(mDNS *const m);
3381 extern mDNSBool mDNSCoreHaveAdvertisedMulticastServices(mDNS *const m);
3382 extern void     mDNSCoreMachineSleep(mDNS *const m, mDNSBool wake);
3383 extern mDNSBool mDNSCoreReadyForSleep(mDNS *m);
3384 extern mDNSs32  mDNSCoreIntervalToNextWake(mDNS *const m, mDNSs32 now);
3385 
3386 extern void     mDNSCoreBeSleepProxyServer(mDNS *const m, mDNSu8 sps, mDNSu8 port, mDNSu8 marginalpower, mDNSu8 totpower);
3387 extern void     mDNSCoreReceiveRawPacket  (mDNS *const m, const mDNSu8 *const p, const mDNSu8 *const end, const mDNSInterfaceID InterfaceID);
3388 
3389 extern mDNSBool mDNSAddrIsDNSMulticast(const mDNSAddr *ip);
3390 
3391 extern CacheRecord *CreateNewCacheEntry(mDNS *const m, const mDNSu32 slot, CacheGroup *cg);
3392 extern void GrantCacheExtensions(mDNS *const m, DNSQuestion *q, mDNSu32 lease);
3393 extern void MakeNegativeCacheRecord(mDNS *const m, CacheRecord *const cr,
3394 	const domainname *const name, const mDNSu32 namehash, const mDNSu16 rrtype, const mDNSu16 rrclass, mDNSu32 ttl_seconds, mDNSInterfaceID InterfaceID);
3395 extern void CompleteDeregistration(mDNS *const m, AuthRecord *rr);
3396 extern void FindSPSInCache(mDNS *const m, const DNSQuestion *const q, const CacheRecord *sps[3]);
3397 #define PrototypeSPSName(X) ((X)[0] >= 11 && (X)[3] == '-' && (X)[ 4] == '9' && (X)[ 5] == '9' && \
3398                                              (X)[6] == '-' && (X)[ 7] == '9' && (X)[ 8] == '9' && \
3399                                              (X)[9] == '-' && (X)[10] == '9' && (X)[11] == '9'    )
3400 #define ValidSPSName(X) ((X)[0] >= 5 && mDNSIsDigit((X)[1]) && mDNSIsDigit((X)[2]) && mDNSIsDigit((X)[4]) && mDNSIsDigit((X)[5]))
3401 #define SPSMetric(X) (!ValidSPSName(X) || PrototypeSPSName(X) ? 1000000 : \
3402 	((X)[1]-'0') * 100000 + ((X)[2]-'0') * 10000 + ((X)[4]-'0') * 1000 + ((X)[5]-'0') * 100 + ((X)[7]-'0') * 10 + ((X)[8]-'0'))
3403 extern void AnswerCurrentQuestionWithResourceRecord(mDNS *const m, CacheRecord *const rr, const QC_result AddRecord);
3404 
3405 // For now this AutoTunnel stuff is specific to Mac OS X.
3406 // In the future, if there's demand, we may see if we can abstract it out cleanly into the platform layer
3407 #if APPLE_OSX_mDNSResponder
3408 extern void AutoTunnelCallback(mDNS *const m, DNSQuestion *question, const ResourceRecord *const answer, QC_result AddRecord);
3409 extern void AddNewClientTunnel(mDNS *const m, DNSQuestion *const q);
3410 extern void SetupLocalAutoTunnelInterface_internal(mDNS *const m);
3411 extern void UpdateAutoTunnelDomainStatuses(const mDNS *const m);
3412 #endif
3413 
3414 // ***************************************************************************
3415 #if 0
3416 #pragma mark -
3417 #pragma mark - Compile-Time assertion checks
3418 #endif
3419 
3420 // Some C compiler cleverness. We can make the compiler check certain things for
3421 // us, and report compile-time errors if anything is wrong. The usual way to do
3422 // this would be to use a run-time "if" statement, but then you don't find out
3423 // what's wrong until you run the software. This way, if the assertion condition
3424 // is false, the array size is negative, and the complier complains immediately.
3425 
3426 struct CompileTimeAssertionChecks_mDNS
3427 	{
3428 	// Check that the compiler generated our on-the-wire packet format structure definitions
3429 	// properly packed, without adding padding bytes to align fields on 32-bit or 64-bit boundaries.
3430 	char assert0[(sizeof(rdataSRV)         == 262                          ) ? 1 : -1];
3431 	char assert1[(sizeof(DNSMessageHeader) ==  12                          ) ? 1 : -1];
3432 	char assert2[(sizeof(DNSMessage)       ==  12+AbsoluteMaxDNSMessageData) ? 1 : -1];
3433 	char assert3[(sizeof(mDNSs8)           ==   1                          ) ? 1 : -1];
3434 	char assert4[(sizeof(mDNSu8)           ==   1                          ) ? 1 : -1];
3435 	char assert5[(sizeof(mDNSs16)          ==   2                          ) ? 1 : -1];
3436 	char assert6[(sizeof(mDNSu16)          ==   2                          ) ? 1 : -1];
3437 	char assert7[(sizeof(mDNSs32)          ==   4                          ) ? 1 : -1];
3438 	char assert8[(sizeof(mDNSu32)          ==   4                          ) ? 1 : -1];
3439 	char assert9[(sizeof(mDNSOpaque16)     ==   2                          ) ? 1 : -1];
3440 	char assertA[(sizeof(mDNSOpaque32)     ==   4                          ) ? 1 : -1];
3441 	char assertB[(sizeof(mDNSOpaque128)    ==  16                          ) ? 1 : -1];
3442 	char assertC[(sizeof(CacheRecord  )    ==  sizeof(CacheGroup)          ) ? 1 : -1];
3443 	char assertD[(sizeof(int)              >=  4                           ) ? 1 : -1];
3444 	char assertE[(StandardAuthRDSize       >=  256                         ) ? 1 : -1];
3445 	char assertF[(sizeof(EthernetHeader)   ==   14                         ) ? 1 : -1];
3446 	char assertG[(sizeof(ARP_EthIP     )   ==   28                         ) ? 1 : -1];
3447 	char assertH[(sizeof(IPv4Header    )   ==   20                         ) ? 1 : -1];
3448 	char assertI[(sizeof(IPv6Header    )   ==   40                         ) ? 1 : -1];
3449 	char assertJ[(sizeof(IPv6ND        )   ==   24                         ) ? 1 : -1];
3450 	char assertK[(sizeof(UDPHeader     )   ==    8                         ) ? 1 : -1];
3451 	char assertL[(sizeof(TCPHeader     )   ==   20                         ) ? 1 : -1];
3452 
3453 	// Check our structures are reasonable sizes. Including overly-large buffers, or embedding
3454 	// other overly-large structures instead of having a pointer to them, can inadvertently
3455 	// cause structure sizes (and therefore memory usage) to balloon unreasonably.
3456 	char sizecheck_RDataBody           [(sizeof(RDataBody)            ==   264) ? 1 : -1];
3457 	char sizecheck_ResourceRecord      [(sizeof(ResourceRecord)       <=    56) ? 1 : -1];
3458 	char sizecheck_AuthRecord          [(sizeof(AuthRecord)           <=  1000) ? 1 : -1];
3459 	char sizecheck_CacheRecord         [(sizeof(CacheRecord)          <=   176) ? 1 : -1];
3460 	char sizecheck_CacheGroup          [(sizeof(CacheGroup)           <=   176) ? 1 : -1];
3461 	char sizecheck_DNSQuestion         [(sizeof(DNSQuestion)          <=   728) ? 1 : -1];
3462 	char sizecheck_ZoneData            [(sizeof(ZoneData)             <=  1560) ? 1 : -1];
3463 	char sizecheck_NATTraversalInfo    [(sizeof(NATTraversalInfo)     <=   192) ? 1 : -1];
3464 	char sizecheck_HostnameInfo        [(sizeof(HostnameInfo)         <=  2800) ? 1 : -1];
3465 	char sizecheck_DNSServer           [(sizeof(DNSServer)            <=   312) ? 1 : -1];
3466 	char sizecheck_NetworkInterfaceInfo[(sizeof(NetworkInterfaceInfo) <=  5968) ? 1 : -1];
3467 	char sizecheck_ServiceRecordSet    [(sizeof(ServiceRecordSet)     <=  5500) ? 1 : -1];
3468 	char sizecheck_DomainAuthInfo      [(sizeof(DomainAuthInfo)       <=  5500) ? 1 : -1];
3469 	char sizecheck_ServiceInfoQuery    [(sizeof(ServiceInfoQuery)     <=  2944) ? 1 : -1];
3470 #if APPLE_OSX_mDNSResponder
3471 	char sizecheck_ClientTunnel        [(sizeof(ClientTunnel)         <=  1072) ? 1 : -1];
3472 #endif
3473 	};
3474 
3475 // ***************************************************************************
3476 
3477 #ifdef __cplusplus
3478 	}
3479 #endif
3480 
3481 #endif
3482