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/* -*- Mode: C; tab-width: 4 -*-
*
* Copyright (c) 2002-2003 Apple Computer, Inc. All rights reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
NOTE:
If you're building an application that uses DNS Service Discovery
this is probably NOT the header file you're looking for.
In most cases you will want to use /usr/include/dns_sd.h instead.
This header file defines the lowest level raw interface to mDNSCore,
which is appropriate *only* on tiny embedded systems where everything
runs in a single address space and memory is extremely constrained.
All the APIs here are malloc-free, which means that the caller is
responsible for passing in a pointer to the relevant storage that
will be used in the execution of that call, and (when called with
correct parameters) all the calls are guaranteed to succeed. There
is never a case where a call can suffer intermittent failures because
the implementation calls malloc() and sometimes malloc() returns NULL
because memory is so limited that no more is available.
This is primarily for devices that need to have precisely known fixed
memory requirements, with absolutely no uncertainty or run-time variation,
but that certainty comes at a cost of more difficult programming.
For applications running on general-purpose desktop operating systems
(Mac OS, Linux, Solaris, Windows, etc.) the API you should use is
/usr/include/dns_sd.h, which defines the API by which multiple
independent client processes communicate their DNS Service Discovery
requests to a single "mdnsd" daemon running in the background.
Even on platforms that don't run multiple independent processes in
multiple independent address spaces, you can still use the preferred
dns_sd.h APIs by linking in "dnssd_clientshim.c", which implements
the standard "dns_sd.h" API calls, allocates any required storage
using malloc(), and then calls through to the low-level malloc-free
mDNSCore routines defined here. This has the benefit that even though
you're running on a small embedded system with a single address space,
you can still use the exact same client C code as you'd use on a
general-purpose desktop system.
Change History (most recent first):
$Log: mDNSEmbeddedAPI.h,v $
Revision 1.577 2009/07/16 00:34:18 cheshire
<rdar://problem/6434656> Sleep Proxy: Put owner OPT records in multicast announcements to avoid conflicts
Additional refinement: If we didn't register with a Sleep Proxy when going to sleep,
we don't need to include our OWNER option in our packets when we re-awaken
Revision 1.576 2009/07/15 23:35:37 cheshire
<rdar://problem/6434656> Sleep Proxy: Put owner OPT records in multicast announcements to avoid conflicts
Revision 1.575 2009/07/11 01:57:00 cheshire
<rdar://problem/6613674> Sleep Proxy: Add support for using sleep proxy in local network interface hardware
Added declaration of ActivateLocalProxy
Revision 1.574 2009/07/10 23:03:17 cheshire
Made SecondLabel(X) more defensive, to guard against the case where the name doesn't have a second label
Revision 1.573 2009/06/30 18:17:45 herscher
Add to 64 bit macro check for 64 bit Windows OSes
Revision 1.572 2009/06/27 00:52:27 cheshire
<rdar://problem/6959273> mDNSResponder taking up 13% CPU with 400 KBps incoming bonjour requests
Removed overly-complicate and ineffective multi-packet known-answer snooping code
(Bracketed it with "#if ENABLE_MULTI_PACKET_QUERY_SNOOPING" for now; will delete actual code later)
Revision 1.571 2009/06/26 01:55:54 cheshire
<rdar://problem/6890712> mDNS: iChat's Buddy photo always appears as the "shadow person" over Bonjour
Additional refinements -- except for the case of explicit queries for record types we don't have (for names we own),
add additional NSEC records only when there's space to do that without having to generate an additional packet
Revision 1.570 2009/06/24 22:14:21 cheshire
<rdar://problem/6911445> Plugging and unplugging the power cable shouldn't cause a network change event
Revision 1.569 2009/06/03 23:07:12 cheshire
<rdar://problem/6890712> mDNS: iChat's Buddy photo always appears as the "shadow person" over Bonjour
Large records were not being added in cases where an NSEC record was also required
Revision 1.568 2009/05/19 22:37:04 cheshire
<rdar://problem/6903507> Sleep Proxy: Retransmission logic not working reliably on quiet networks
Added NextScheduledSPRetry field
Revision 1.567 2009/05/13 17:25:33 mkrochma
<rdar://problem/6879926> Should not schedule maintenance wake when machine has no advertised services
Sleep proxy client should only look for services being advertised via Multicast
Revision 1.566 2009/05/12 23:09:24 cheshire
<rdar://problem/6879926> Should not schedule maintenance wake when machine has no advertised services
Declare mDNSCoreHaveAdvertisedServices routine so it can be called from daemon.c
Revision 1.565 2009/05/09 00:10:58 jessic2
Change expected size of NetworkInterfaceInfo to fix build failure
Revision 1.564 2009/05/07 23:31:26 cheshire
<rdar://problem/6601427> Sleep Proxy: Retransmit and retry Sleep Proxy Server requests
Added NextSPSAttempt and NextSPSAttemptTime fields to NetworkInterfaceInfo_struct
Revision 1.563 2009/04/24 21:06:38 cheshire
Added comment about UDP length field (includes UDP header, so minimum value is 8 bytes)
Revision 1.562 2009/04/24 00:22:23 cheshire
<rdar://problem/3476350> Return negative answers when host knows authoritatively that no answer exists
Added definition of rdataNSEC
Revision 1.561 2009/04/23 22:06:29 cheshire
Added CacheRecord and InterfaceID parameters to MakeNegativeCacheRecord, in preparation for:
<rdar://problem/3476350> Return negative answers when host knows authoritatively that no answer exists
Revision 1.560 2009/04/23 21:54:50 cheshire
Updated comments
Revision 1.559 2009/04/22 00:37:38 cheshire
<rdar://problem/6814427> Remove unused kDNSType_MAC
Revision 1.558 2009/04/21 23:36:25 cheshire
<rdar://problem/6814427> Remove unused kDNSType_MAC
Revision 1.557 2009/04/15 20:42:51 mcguire
<rdar://problem/6768947> uDNS: Treat RCODE 5 (Refused) responses as failures
Revision 1.556 2009/04/11 00:19:43 jessic2
<rdar://problem/4426780> Daemon: Should be able to turn on LogOperation dynamically
Revision 1.555 2009/04/01 21:12:27 herscher
<rdar://problem/5925472> Current Bonjour code does not compile on Windows.
Revision 1.554 2009/04/01 17:50:11 mcguire
cleanup mDNSRandom
Revision 1.553 2009/03/26 03:59:00 jessic2
Changes for <rdar://problem/6492552&6492593&6492609&6492613&6492628&6492640&6492699>
Revision 1.552 2009/03/20 23:53:03 jessic2
<rdar://problem/6646228> SIGHUP should restart all in-progress queries
Revision 1.551 2009/03/18 20:41:04 cheshire
Added definition of the all-ones mDNSOpaque16 ID
Revision 1.550 2009/03/17 19:10:29 mcguire
Fix sizechecks for x86_64
Revision 1.549 2009/03/17 01:22:56 cheshire
<rdar://problem/6601427> Sleep Proxy: Retransmit and retry Sleep Proxy Server requests
Initial support for resolving up to three Sleep Proxies in parallel
Revision 1.548 2009/03/14 01:42:56 mcguire
<rdar://problem/5457116> BTMM: Fix issues with multiple .Mac accounts on the same machine
Revision 1.547 2009/03/10 01:14:30 cheshire
Sleep Proxies with invalid names need to be ignored (score 10000),
not treated as "Sleep Proxy of last resort" (score 9999)
Revision 1.546 2009/03/06 23:51:51 mcguire
Fix broken build by defining DiscardPort
Revision 1.545 2009/03/06 22:39:23 cheshire
<rdar://problem/6655850> Ignore prototype base stations when picking Sleep Proxy to register with
Revision 1.544 2009/03/04 01:33:30 cheshire
Add m->ProxyRecords counter
Revision 1.543 2009/03/03 23:04:43 cheshire
For clarity, renamed "MAC" field to "HMAC" (Host MAC, as opposed to Interface MAC)
Revision 1.542 2009/03/03 22:51:53 cheshire
<rdar://problem/6504236> Sleep Proxy: Waking on same network but different interface will cause conflicts
Revision 1.541 2009/03/03 00:45:19 cheshire
Added m->PrimaryMAC field
Revision 1.540 2009/02/27 02:56:57 cheshire
Moved struct SearchListElem definition from uDNS.c into mDNSEmbeddedAPI.h
Revision 1.539 2009/02/17 23:29:01 cheshire
Throttle logging to a slower rate when running on SnowLeopard
Revision 1.538 2009/02/11 02:31:57 cheshire
Moved SystemWakeOnLANEnabled from mDNSMacOSX.h, so it's accessible to mDNSCore routines
Revision 1.537 2009/02/07 02:51:48 cheshire
<rdar://problem/6084043> Sleep Proxy: Need to adopt IOPMConnection
Added new functions and timing variables
Revision 1.536 2009/01/30 23:50:31 cheshire
Added LastLabel() routine to get the last label of a domainname
Revision 1.535 2009/01/23 00:38:36 mcguire
<rdar://problem/5570906> BTMM: Doesn't work with Linksys WRT54GS firmware 4.71.1
Revision 1.534 2009/01/22 02:14:25 cheshire
<rdar://problem/6515626> Sleep Proxy: Set correct target MAC address, instead of all zeroes
Revision 1.533 2009/01/21 03:43:57 mcguire
<rdar://problem/6511765> BTMM: Add support for setting kDNSServiceErr_NATPortMappingDisabled in DynamicStore
Revision 1.532 2009/01/16 19:50:36 cheshire
Oops. Fixed definition of SleepProxyServiceType.
Revision 1.531 2009/01/16 19:48:09 cheshire
Added definition of SleepProxyServiceType
Revision 1.530 2009/01/15 00:22:49 mcguire
<rdar://problem/6437092> NAT-PMP: mDNSResponder needs to listen on 224.0.0.1:5350/UDP with REUSEPORT
Revision 1.529 2009/01/13 00:31:44 cheshire
Fixed off-by-one error in computing the implicit limit pointer in the "DomainNameLength(name)" macro
Revision 1.528 2009/01/10 01:43:52 cheshire
Changed misleading function name 'AnsweredLOQ' to more informative 'AnsweredLocalQ'
Revision 1.527 2008/12/12 01:23:19 cheshire
Added m->SPSProxyListChanged state variable to flag when we need to update our BPF filter program
Revision 1.526 2008/12/12 00:51:14 cheshire
Added structure definitions for IPv6Header, etc.
Revision 1.525 2008/12/10 02:18:31 cheshire
Increased MaxMsg to 160 for showing longer TXT records in SIGINFO output
Revision 1.524 2008/12/10 01:49:39 cheshire
Fixes for alignment issues on ARMv5
Revision 1.523 2008/12/05 02:35:24 mcguire
<rdar://problem/6107390> Write to the DynamicStore when a Sleep Proxy server is available on the network
Revision 1.522 2008/12/04 21:08:51 mcguire
<rdar://problem/6116863> mDNS: Provide mechanism to disable Multicast advertisements
Revision 1.521 2008/12/04 02:19:24 cheshire
Updated comment
Revision 1.520 2008/11/26 20:28:05 cheshire
Added new SSHPort constant
Revision 1.519 2008/11/25 22:46:30 cheshire
For ease of code searching, renamed ZoneData field of ServiceRecordSet_struct from "nta" to "srs_nta"
Revision 1.518 2008/11/25 05:07:15 cheshire
<rdar://problem/6374328> Advertise Sleep Proxy metrics in service name
Revision 1.517 2008/11/20 01:51:19 cheshire
Exported RecreateNATMappings so it's callable from other files
Revision 1.516 2008/11/16 16:49:25 cheshire
<rdar://problem/6375808> LLQs broken in mDNSResponder-184
DNSOpt_LLQData_Space was incorrectly defined to be 18 instead of 22
Revision 1.515 2008/11/14 20:59:41 cheshire
Added mDNSEthAddressIsZero(A) macro
Revision 1.514 2008/11/14 02:17:41 cheshire
Added NextScheduledSPS task scheduling variable
Revision 1.513 2008/11/14 00:47:19 cheshire
Added TimeRcvd and TimeExpire fields to AuthRecord_struct
Revision 1.512 2008/11/14 00:00:53 cheshire
After client machine wakes up, Sleep Proxy machine need to remove any records
it was temporarily holding as proxy for that client
Revision 1.511 2008/11/13 19:04:44 cheshire
Added definition of OwnerOptData
Revision 1.510 2008/11/06 23:48:32 cheshire
Changed SleepProxyServerType to mDNSu8
Revision 1.509 2008/11/04 23:06:50 cheshire
Split RDataBody union definition into RDataBody and RDataBody2, and removed
SOA from the normal RDataBody union definition, saving 270 bytes per AuthRecord
Revision 1.508 2008/11/04 22:21:43 cheshire
Changed zone field of AuthRecord_struct from domainname to pointer, saving 252 bytes per AuthRecord
Revision 1.507 2008/11/04 22:13:43 cheshire
Made RDataBody parameter to GetRRDisplayString_rdb "const"
Revision 1.506 2008/11/04 20:06:19 cheshire
<rdar://problem/6186231> Change MAX_DOMAIN_NAME to 256
Revision 1.505 2008/11/03 23:49:47 mkrochma
Increase NATMAP_DEFAULT_LEASE to 2 hours so we do maintenance wake less often
Revision 1.504 2008/10/31 22:55:04 cheshire
Initial support for structured SPS names
Revision 1.503 2008/10/24 23:58:47 cheshire
Ports should be mDNSIPPort, not mDNSOpaque16
Revision 1.502 2008/10/23 22:25:56 cheshire
Renamed field "id" to more descriptive "updateid"
Revision 1.501 2008/10/22 22:22:27 cheshire
Added packet structure definitions
Revision 1.500 2008/10/22 19:55:35 cheshire
Miscellaneous fixes; renamed FindFirstAnswerInCache to FindSPSInCache
Revision 1.499 2008/10/22 17:15:47 cheshire
Updated definitions of mDNSIPv4AddressIsZero/mDNSIPv4AddressIsOnes, etc.
Revision 1.498 2008/10/22 01:01:52 cheshire
Added onesEthAddr constant, used for sending ARP broadcasts
Revision 1.497 2008/10/21 00:51:11 cheshire
Added declaration of mDNSPlatformSetBPF(), used by uds_daemon.c to pass BPF fd to mDNSMacOSX.c
Revision 1.496 2008/10/16 22:38:52 cheshire
Added declaration of mDNSCoreReceiveRawPacket()
Revision 1.495 2008/10/15 22:53:51 cheshire
Removed unused "#define LocalReverseMapDomain"
Revision 1.494 2008/10/15 20:37:17 cheshire
Added "#define DNSOpt_Lease_Space 19"
Revision 1.493 2008/10/14 21:37:56 cheshire
Removed unnecessary m->BeSleepProxyServer variable
Revision 1.492 2008/10/14 20:26:36 cheshire
Added definition of a new kDNSType_MAC rdata type
Revision 1.491 2008/10/09 22:29:04 cheshire
Added "mDNSEthAddr MAC" to NetworkInterfaceInfo_struct
Revision 1.490 2008/10/09 21:39:20 cheshire
Update list of DNS types
Revision 1.489 2008/10/09 18:59:19 cheshire
Added NetWakeResolve code, removed unused m->SendDeregistrations and m->SendImmediateAnswers
Revision 1.488 2008/10/08 01:02:03 cheshire
Added mDNS_SetupQuestion() convenience function
Revision 1.487 2008/10/07 21:41:57 mcguire
Increase sizecheck limits to account for DNSQuestion added to NetworkInterfaceInfo_struct in 64bit builds
Revision 1.486 2008/10/07 15:56:24 cheshire
Increase sizecheck limits to account for DNSQuestion added to NetworkInterfaceInfo_struct
Revision 1.485 2008/10/04 00:48:37 cheshire
Added DNSQuestion to NetworkInterfaceInfo_struct, used for browsing for Sleep Proxy Servers
Revision 1.484 2008/10/04 00:01:45 cheshire
Move NetworkInterfaceInfo_struct further down in file (we'll need to add a DNSQuestion to it later)
Revision 1.483 2008/10/03 23:28:41 cheshire
Added declaration of mDNSPlatformSendRawPacket
Revision 1.482 2008/10/03 17:30:05 cheshire
Added declaration of mDNS_ConfigChanged(mDNS *const m);
Revision 1.481 2008/10/02 22:38:58 cheshire
Added SleepProxyServer fields, and mDNSCoreBeSleepProxyServer() call for turning SleepProxyServer on and off
Revision 1.480 2008/10/01 21:22:17 cheshire
Added NetWake field to NetworkInterfaceInfo structure, to signal when Wake-On-Magic-Packet is enabled for that interface
Revision 1.479 2008/09/29 20:12:37 cheshire
Rename 'AnswerLocalQuestions' to more descriptive 'AnswerLocalOnlyQuestions' and 'AnsweredLocalQ' to 'AnsweredLOQ'
Revision 1.478 2008/09/23 02:37:10 cheshire
Added FirstLabel/SecondLabel macros
Revision 1.477 2008/09/20 00:34:22 mcguire
<rdar://problem/6129039> BTMM: Add support for WANPPPConnection
Revision 1.476 2008/09/05 22:22:01 cheshire
Move "UDPSocket *LocalSocket" field to more logical place in DNSQuestion_struct
Revision 1.475 2008/07/25 22:34:11 mcguire
fix sizecheck issues for 64bit
Revision 1.474 2008/07/24 20:23:03 cheshire
<rdar://problem/3988320> Should use randomized source ports and transaction IDs to avoid DNS cache poisoning
Revision 1.473 2008/07/18 21:37:42 mcguire
<rdar://problem/5736845> BTMM: alternate SSDP queries between multicast & unicast
Revision 1.472 2008/07/01 01:39:59 mcguire
<rdar://problem/5823010> 64-bit fixes
Revision 1.471 2008/06/26 17:24:11 mkrochma
<rdar://problem/5450912> BTMM: Stop listening on UDP 5351 for NAT Status Announcements
Revision 1.470 2008/06/19 01:20:49 mcguire
<rdar://problem/4206534> Use all configured DNS servers
Revision 1.469 2008/03/07 18:56:02 cheshire
<rdar://problem/5777647> dnsbugtest query every three seconds when source IP address of response doesn't match
Revision 1.468 2008/03/06 02:48:34 mcguire
<rdar://problem/5321824> write status to the DS
Revision 1.467 2008/02/26 20:48:46 cheshire
Need parentheses around use of macro argument in mDNS_TimeNow_NoLock(m)
Revision 1.466 2008/02/21 21:36:32 cheshire
Updated comment about record type values (kDNSRecordTypePacketAns/Auth/Add)
Revision 1.465 2008/02/20 00:39:05 mcguire
<rdar://problem/5427102> Some device info XML blobs too large
Revision 1.464 2008/01/31 23:33:29 mcguire
<rdar://problem/5614450> changes to build using gcc 4.2 with -Werror
Revision 1.463 2007/12/17 23:53:25 cheshire
Added DNSDigest_SignMessageHostByteOrder, for signing messages not yet converted to network byte order
Revision 1.462 2007/12/17 23:48:29 cheshire
DNSDigest_SignMessage doesn't need to return a result -- it already updates the 'end' parameter
Revision 1.461 2007/12/15 00:18:51 cheshire
Renamed question->origLease to question->ReqLease
Revision 1.460 2007/12/14 23:55:28 cheshire
Moved "struct tcpInfo_t" definition from uDNS.c to mDNSEmbeddedAPI.h
Revision 1.459 2007/12/07 22:40:34 cheshire
Rename 'LocalAnswer' to more descriptive 'AnsweredLocalQ'
Revision 1.458 2007/12/07 00:45:58 cheshire
<rdar://problem/5526800> BTMM: Need to clean up registrations on shutdown
Revision 1.457 2007/12/06 00:22:27 mcguire
<rdar://problem/5604567> BTMM: Doesn't work with Linksys WAG300N 1.01.06 (sending from 1026/udp)
Revision 1.456 2007/12/05 01:45:35 cheshire
Renamed markedForDeletion -> MarkedForDeletion
Revision 1.455 2007/12/01 01:21:27 jgraessley
<rdar://problem/5623140> mDNSResponder unicast DNS improvements
Revision 1.454 2007/12/01 00:34:03 cheshire
Fixes from Bob Bradley for building on EFI
Revision 1.453 2007/10/29 23:51:22 cheshire
Added comment about NATTraversalInfo ExternalAddress field
Revision 1.452 2007/10/29 18:13:40 cheshire
Added Question_uDNS macro, analogous to AuthRecord_uDNS macro
Revision 1.451 2007/10/26 23:42:57 cheshire
Removed unused "mDNSs32 expire" field from ServiceRecordSet_struct
Revision 1.450 2007/10/26 22:24:08 cheshire
Added AuthRecord_uDNS() macro to determine when a given AuthRecord needs to be registered via unicast DNS
Revision 1.449 2007/10/25 20:48:47 cheshire
For naming consistency (with AuthRecord's UpdateServer) renamed 'ns' to 'SRSUpdateServer'
Revision 1.448 2007/10/22 22:19:44 cheshire
Tidied up code alignment
Revision 1.447 2007/10/22 19:40:30 cheshire
<rdar://problem/5519458> BTMM: Machines don't appear in the sidebar on wake from sleep
Made subroutine mDNSPlatformSourceAddrForDest(mDNSAddr *const src, const mDNSAddr *const dst)
Revision 1.446 2007/10/17 22:49:54 cheshire
<rdar://problem/5519458> BTMM: Machines don't appear in the sidebar on wake from sleep
Revision 1.445 2007/10/17 22:37:23 cheshire
<rdar://problem/5536979> BTMM: Need to create NAT port mapping for receiving LLQ events
Revision 1.444 2007/09/29 03:14:52 cheshire
<rdar://problem/5513168> BTMM: mDNSResponder memory corruption in GetAuthInfoForName_internal
Added AutoTunnelUnregistered macro to check state of DomainAuthInfo AuthRecords
Revision 1.443 2007/09/27 21:21:39 cheshire
Export CompleteDeregistration so it's callable from other files
Revision 1.442 2007/09/27 00:25:39 cheshire
Added ttl_seconds parameter to MakeNegativeCacheRecord in preparation for:
<rdar://problem/4947392> uDNS: Use SOA to determine TTL for negative answers
Revision 1.441 2007/09/26 23:17:49 cheshire
Get rid of unused kWideAreaTTL constant
Revision 1.440 2007/09/26 22:06:02 cheshire
<rdar://problem/5507399> BTMM: No immediate failure notifications for BTMM names
Revision 1.439 2007/09/21 21:12:36 cheshire
DNSDigest_SignMessage does not need separate "mDNSu16 *numAdditionals" parameter
Revision 1.438 2007/09/19 20:32:09 cheshire
Export GetAuthInfoForName so it's callable from other files
Revision 1.437 2007/09/18 21:42:29 cheshire
To reduce programming mistakes, renamed ExtPort to RequestedPort
Revision 1.436 2007/09/14 21:26:08 cheshire
<rdar://problem/5482627> BTMM: Need to manually avoid port conflicts when using UPnP gateways
Revision 1.435 2007/09/13 00:16:41 cheshire
<rdar://problem/5468706> Miscellaneous NAT Traversal improvements
Revision 1.434 2007/09/12 23:03:07 cheshire
<rdar://problem/5476978> DNSServiceNATPortMappingCreate callback not giving correct interface index
Revision 1.433 2007/09/12 22:19:28 cheshire
<rdar://problem/5476977> Need to listen for port 5350 NAT-PMP announcements
Revision 1.432 2007/09/12 19:22:19 cheshire
Variable renaming in preparation for upcoming fixes e.g. priv/pub renamed to intport/extport
Made NAT Traversal packet handlers take typed data instead of anonymous "mDNSu8 *" byte pointers
Revision 1.431 2007/09/11 19:19:16 cheshire
Correct capitalization of "uPNP" to "UPnP"
Revision 1.430 2007/09/10 22:06:50 cheshire
Rename uptime => upseconds and LastNATUptime => LastNATupseconds to make it clear these time values are in seconds
Revision 1.429 2007/09/07 21:16:58 cheshire
Add new symbol "NATPMPAnnouncementPort" (5350)
Revision 1.428 2007/09/05 21:48:01 cheshire
<rdar://problem/5385864> BTMM: mDNSResponder flushes wide-area Bonjour records after an hour for a zone.
Now that we're respecting the TTL of uDNS records in the cache, the LLQ maintenance code needs
to update the cache lifetimes of all relevant records every time it successfully renews an LLQ,
otherwise those records will expire and vanish from the cache.
Revision 1.427 2007/09/05 20:47:12 cheshire
Tidied up alignment of code layout
Revision 1.426 2007/09/04 20:37:06 cheshire
<rdar://problem/5457287> mDNSResponder taking up 100% CPU in ReissueBlockedQuestions
Reorder fields into more logical order, with AuthInfo before DuplicateOf
Revision 1.425 2007/08/31 19:53:14 cheshire
<rdar://problem/5431151> BTMM: IPv6 address lookup should not succeed if autotunnel cannot be setup
If AutoTunnel setup fails, the code now generates a fake NXDomain error saying that the requested AAAA record does not exist
Revision 1.424 2007/08/31 18:49:49 vazquez
<rdar://problem/5393719> BTMM: Need to properly deregister when stopping BTMM
Revision 1.423 2007/08/31 00:04:28 cheshire
Added comment explaining deltime in DomainAuthInfo structure
Revision 1.422 2007/08/28 23:58:42 cheshire
Rename HostTarget -> AutoTarget
Revision 1.421 2007/08/27 20:30:43 cheshire
Only include TunnelClients list when building for OS X
Revision 1.420 2007/08/23 21:47:09 vazquez
<rdar://problem/5427316> BTMM: mDNSResponder sends NAT-PMP packets on public network
make sure we clean up port mappings on base stations by sending a lease value of 0,
and only send NAT-PMP packets on private networks; also save some memory by
not using packet structs in NATTraversals.
Revision 1.419 2007/08/08 21:07:47 vazquez
<rdar://problem/5244687> BTMM: Need to advertise model information via wide-area bonjour
Revision 1.418 2007/08/01 16:09:13 cheshire
Removed unused NATTraversalInfo substructure from AuthRecord; reduced structure sizecheck values accordingly
Revision 1.417 2007/08/01 03:04:59 cheshire
Add NATTraversalInfo structures to HostnameInfo and DomainAuthInfo
Revision 1.416 2007/08/01 00:04:13 cheshire
<rdar://problem/5261696> Crash in tcpKQSocketCallback
Half-open TCP connections were not being cancelled properly
Revision 1.415 2007/07/31 02:28:35 vazquez
<rdar://problem/3734269> NAT-PMP: Detect public IP address changes and base station reboot
Revision 1.414 2007/07/30 23:34:19 cheshire
Remove unused "udpSock" from DNSQuestion
Revision 1.413 2007/07/28 01:25:56 cheshire
<rdar://problem/4780038> BTMM: Add explicit UDP event port to LLQ setup request, to fix LLQs not working behind NAT
Revision 1.412 2007/07/27 23:57:23 cheshire
Added compile-time structure size checks
Revision 1.411 2007/07/27 22:50:08 vazquez
Allocate memory for UPnP request and reply buffers instead of using arrays
Revision 1.410 2007/07/27 19:37:19 cheshire
Moved AutomaticBrowseDomainQ into main mDNS object
Revision 1.409 2007/07/27 19:30:39 cheshire
Changed mDNSQuestionCallback parameter from mDNSBool to QC_result,
to properly reflect tri-state nature of the possible responses
Revision 1.408 2007/07/27 18:44:01 cheshire
Rename "AnswerQuestionWithResourceRecord" to more informative "AnswerCurrentQuestionWithResourceRecord"
Revision 1.407 2007/07/26 21:19:26 vazquez
Retry port mapping with incremented port number (up to max) in order to handle
port mapping conflicts on UPnP gateways
Revision 1.406 2007/07/25 22:19:59 cheshire
ClientTunnel structure also needs a rmt_outer_port field
Revision 1.405 2007/07/25 03:05:02 vazquez
Fixes for:
<rdar://problem/5338913> LegacyNATTraversal: UPnP heap overflow
<rdar://problem/5338933> LegacyNATTraversal: UPnP stack buffer overflow
and a myriad of other security problems
Revision 1.404 2007/07/24 20:22:07 cheshire
Add AutoTunnelHostAddrActive flag
Revision 1.403 2007/07/24 04:14:29 cheshire
<rdar://problem/5356281> LLQs not working in with NAT Traversal
Revision 1.402 2007/07/21 00:54:44 cheshire
<rdar://problem/5344576> Delay IPv6 address callback until AutoTunnel route and policy is configured
Revision 1.401 2007/07/20 20:01:38 cheshire
Rename "mDNS_DomainTypeBrowseLegacy" as "mDNS_DomainTypeBrowseAutomatic"
Revision 1.400 2007/07/20 00:54:18 cheshire
<rdar://problem/4641118> Need separate SCPreferences for per-user .Mac settings
Revision 1.399 2007/07/18 03:22:35 cheshire
SetupLocalAutoTunnelInterface_internal needs to be callable from uDNS.c
Revision 1.398 2007/07/18 02:26:56 cheshire
Don't need to declare UpdateTunnels here
Revision 1.397 2007/07/18 01:03:50 cheshire
<rdar://problem/5303834> Automatically configure IPSec policy when resolving services
Add list of client tunnels so we can automatically reconfigure when local address changes
Revision 1.396 2007/07/16 23:54:48 cheshire
<rdar://problem/5338850> Crash when removing or changing DNS keys
Revision 1.395 2007/07/16 20:12:33 vazquez
<rdar://problem/3867231> LegacyNATTraversal: Need complete rewrite
Revision 1.394 2007/07/12 02:51:27 cheshire
<rdar://problem/5303834> Automatically configure IPSec policy when resolving services
Revision 1.393 2007/07/11 23:43:42 cheshire
Rename PurgeCacheResourceRecord to mDNS_PurgeCacheResourceRecord
Revision 1.392 2007/07/11 22:44:40 cheshire
<rdar://problem/5328801> SIGHUP should purge the cache
Revision 1.391 2007/07/11 20:30:45 cheshire
<rdar://problem/5304766> Register IPSec tunnel with IPv4-only hostname and create NAT port mappings
Added AutoTunnelTarget and AutoTunnelService to DomainAuthInfo structure
Revision 1.390 2007/07/11 18:56:55 cheshire
Added comments about AutoTunnelHostAddr and AutoTunnelLabel
Revision 1.389 2007/07/11 02:44:03 cheshire
<rdar://problem/5303807> Register IPv6-only hostname and don't create port mappings for AutoTunnel services
Added AutoTunnel fields to structures
Revision 1.388 2007/07/10 01:53:18 cheshire
<rdar://problem/5196524> uDNS: mDNSresponder is leaking TCP connections to DNS server
AuthRecord, ServiceRecordSet, and DNSQuestion structures need tcpInfo_t pointers
so they can keep track of what TCP connections they open
Revision 1.387 2007/07/06 18:55:15 cheshire
Add explicit NextScheduledNATOp scheduling variable
Revision 1.386 2007/07/03 20:54:11 cheshire
Tidied up code layout of NATTraversalInfo_struct fields and comments
Revision 1.385 2007/07/03 00:40:23 vazquez
More changes for <rdar://problem/5301908> Clean up NAT state machine (necessary for 6 other fixes)
Safely deal with packet replies and client callbacks
Revision 1.384 2007/06/29 00:08:07 vazquez
<rdar://problem/5301908> Clean up NAT state machine (necessary for 6 other fixes)
Revision 1.383 2007/06/20 01:10:12 cheshire
<rdar://problem/5280520> Sync iPhone changes into main mDNSResponder code
Revision 1.382 2007/06/19 20:31:59 cheshire
Add DNSServer_Disabled state
Add mDNSInterfaceID for DNS servers reachable over specific interfaces
Revision 1.381 2007/06/15 18:11:16 cheshire
<rdar://problem/5174466> mDNSResponder crashed in memove() near end of MobileSafari stress test
Made AssignDomainName more defensive when source name is garbage
Revision 1.380 2007/05/25 00:04:51 cheshire
Added comment explaining rdlength
Revision 1.379 2007/05/21 18:04:40 cheshire
Updated comments -- port_mapping_create_reply renamed to port_mapping_reply
Revision 1.378 2007/05/17 19:11:46 cheshire
Tidy up code layout
Revision 1.377 2007/05/15 00:43:33 cheshire
Remove unused regState_Cancelled
Revision 1.376 2007/05/14 23:51:49 cheshire
Added constants MAX_REVERSE_MAPPING_NAME_V4 and MAX_REVERSE_MAPPING_NAME_V6
Revision 1.375 2007/05/10 21:19:18 cheshire
Rate-limit DNS test queries to at most one per three seconds
(useful when we have a dozen active WAB queries, and then we join a new network)
Revision 1.374 2007/05/07 22:07:47 cheshire
<rdar://problem/4738025> Enhance GetLargeResourceRecord to decompress more record types
Revision 1.373 2007/05/07 20:43:45 cheshire
<rdar://problem/4241419> Reduce the number of queries and announcements
Revision 1.372 2007/05/04 22:15:29 cheshire
Get rid of unused q->RestartTime
Revision 1.371 2007/05/03 22:40:37 cheshire
<rdar://problem/4669229> mDNSResponder ignores bogus null target in SRV record
Revision 1.370 2007/05/02 22:18:09 cheshire
Renamed NATTraversalInfo_struct context to NATTraversalContext
Revision 1.369 2007/05/01 21:21:42 cheshire
Add missing parentheses in LEASE_OPT_RDLEN definition
Revision 1.368 2007/04/30 21:33:38 cheshire
Fix crash when a callback unregisters a service while the UpdateSRVRecords() loop
is iterating through the m->ServiceRegistrations list
Revision 1.367 2007/04/28 01:31:59 cheshire
Improve debugging support for catching memory corruption problems
Revision 1.366 2007/04/27 19:28:02 cheshire
Any code that calls StartGetZoneData needs to keep a handle to the structure, so
it can cancel it if necessary. (First noticed as a crash in Apple Remote Desktop
-- it would start a query and then quickly cancel it, and then when
StartGetZoneData completed, it had a dangling pointer and crashed.)
Revision 1.365 2007/04/26 00:35:15 cheshire
<rdar://problem/5140339> uDNS: Domain discovery not working over VPN
Fixes to make sure results update correctly when connectivity changes (e.g. a DNS server
inside the firewall may give answers where a public one gives none, and vice versa.)
Revision 1.364 2007/04/24 02:07:42 cheshire
<rdar://problem/4246187> Identical client queries should reference a single shared core query
Deleted some more redundant code
Revision 1.363 2007/04/24 00:09:47 cheshire
Remove MappedV4 field from mDNS_struct (not actually used anywhere)
Revision 1.362 2007/04/22 06:02:02 cheshire
<rdar://problem/4615977> Query should immediately return failure when no server
Revision 1.361 2007/04/21 19:43:33 cheshire
Code tidying: represent NAT opcodes as bitwise combinations rather than numerical additions
Revision 1.360 2007/04/20 21:17:24 cheshire
For naming consistency, kDNSRecordTypeNegative should be kDNSRecordTypePacketNegative
Revision 1.359 2007/04/19 22:50:53 cheshire
<rdar://problem/4246187> Identical client queries should reference a single shared core query
Revision 1.358 2007/04/19 20:06:41 cheshire
Rename field 'Private' (sounds like a boolean) to more informative 'AuthInfo' (it's a DomainAuthInfo pointer)
Revision 1.357 2007/04/19 18:14:51 cheshire
In mDNS_AddSearchDomain_CString check for NULL pointer before calling MakeDomainNameFromDNSNameString()
Revision 1.356 2007/04/18 20:56:46 cheshire
Added mDNS_AddSearchDomain_CString macro
Revision 1.355 2007/04/17 19:21:29 cheshire
<rdar://problem/5140339> Domain discovery not working over VPN
Revision 1.354 2007/04/05 22:55:34 cheshire
<rdar://problem/5077076> Records are ending up in Lighthouse without expiry information
Revision 1.353 2007/04/05 20:40:37 cheshire
Remove unused mDNSPlatformTCPGetFlags()
Revision 1.352 2007/04/04 21:48:52 cheshire
<rdar://problem/4720694> Combine unicast authoritative answer list with multicast list
Revision 1.351 2007/04/04 01:27:45 cheshire
Update comment
Revision 1.350 2007/04/04 00:03:26 cheshire
<rdar://problem/5089862> DNSServiceQueryRecord is returning kDNSServiceErr_NoSuchRecord for empty rdata
Revision 1.349 2007/04/03 19:37:58 cheshire
Rename mDNSAddrIsv4Private() to more precise mDNSAddrIsRFC1918()
Revision 1.348 2007/04/03 19:13:39 cheshire
Added macros mDNSSameIPPort, mDNSSameOpaque16, mDNSIPPortIsZero, mDNSOpaque16IsZero
Revision 1.347 2007/03/28 20:59:26 cheshire
<rdar://problem/4743285> Remove inappropriate use of IsPrivateV4Addr()
Revision 1.346 2007/03/28 15:56:37 cheshire
<rdar://problem/5085774> Add listing of NAT port mapping and GetAddrInfo requests in SIGINFO output
Revision 1.345 2007/03/22 19:29:23 cheshire
Add comment and check to ensure StandardAuthRDSize is at least 256 bytes
Revision 1.344 2007/03/22 18:31:48 cheshire
Put dst parameter first in mDNSPlatformStrCopy/mDNSPlatformMemCopy, like conventional Posix strcpy/memcpy
Revision 1.343 2007/03/22 00:49:20 cheshire
<rdar://problem/4848295> Advertise model information via Bonjour
Revision 1.342 2007/03/21 23:06:00 cheshire
Rename uDNS_HostnameInfo to HostnameInfo; deleted some unused fields
Revision 1.341 2007/03/21 20:44:11 cheshire
Added mDNSAddressIsv4LinkLocal macro
Revision 1.340 2007/03/21 00:30:02 cheshire
<rdar://problem/4789455> Multiple errors in DNameList-related code
Revision 1.339 2007/03/20 17:07:15 cheshire
Rename "struct uDNS_TCPSocket_struct" to "TCPSocket", "struct uDNS_UDPSocket_struct" to "UDPSocket"
Revision 1.338 2007/03/10 02:28:28 cheshire
Added comment explaining NATResponseHndlr
Revision 1.337 2007/03/10 02:02:58 cheshire
<rdar://problem/4961667> uDNS: LLQ refresh response packet causes cached records to be removed from cache
Eliminate unnecessary "InternalResponseHndlr responseCallback" function pointer
Revision 1.336 2007/02/28 22:12:24 cheshire
Get rid of unused mDNSVal32 and mDNSOpaque32fromIntVal
Revision 1.335 2007/02/28 21:49:07 cheshire
Off-by-one error: SameDomainLabelCS (case-sensitive) was stopping one character short of
the end of the label, e.g. it would fail to detect that "chesh1" and "chesh2" are different.
Revision 1.334 2007/02/28 01:44:26 cheshire
<rdar://problem/5027863> Byte order bugs in uDNS.c, uds_daemon.c, dnssd_clientstub.c
Revision 1.333 2007/02/27 22:55:22 cheshire
Get rid of unused AllDNSLinkGroupv4 and AllDNSLinkGroupv6
Revision 1.332 2007/02/27 02:48:24 cheshire
Parameter to LNT_GetPublicIP function is IPv4 address, not anonymous "mDNSOpaque32" object
Revision 1.331 2007/02/14 03:16:39 cheshire
<rdar://problem/4789477> Eliminate unnecessary malloc/free in mDNSCore code
Revision 1.330 2007/02/08 21:12:28 cheshire
<rdar://problem/4386497> Stop reading /etc/mDNSResponder.conf on every sleep/wake
Revision 1.329 2007/02/07 01:19:36 cheshire
<rdar://problem/4849427> API: Reconcile conflicting error code values
Revision 1.328 2007/01/25 00:19:40 cheshire
Add CNAMEReferrals field to DNSQuestion_struct
Revision 1.327 2007/01/23 02:56:10 cheshire
Store negative results in the cache, instead of generating them out of pktResponseHndlr()
Revision 1.326 2007/01/20 01:30:49 cheshire
Update comments
Revision 1.325 2007/01/19 18:39:11 cheshire
Fix a bunch of parameters that should have been declared "const"
Revision 1.324 2007/01/19 18:04:04 cheshire
For naming consistency, use capital letters for RR types: rdataOpt should be rdataOPT
Revision 1.323 2007/01/17 21:46:02 cheshire
Remove redundant duplicated "isPrivate" field from LLQ_Info
Revision 1.322 2007/01/10 22:51:56 cheshire
<rdar://problem/4917539> Add support for one-shot private queries as well as long-lived private queries
Revision 1.321 2007/01/09 22:37:18 cheshire
Provide ten-second grace period for deleted keys, to give mDNSResponder
time to delete host name before it gives up access to the required key.
Revision 1.320 2007/01/05 08:30:41 cheshire
Trim excessive "$Log" checkin history from before 2006
(checkin history still available via "cvs log ..." of course)
Revision 1.319 2007/01/04 23:11:11 cheshire
<rdar://problem/4720673> uDNS: Need to start caching unicast records
When an automatic browsing domain is removed, generate appropriate "remove" events for legacy queries
Revision 1.318 2007/01/04 20:57:48 cheshire
Rename ReturnCNAME to ReturnIntermed (for ReturnIntermediates)
Revision 1.317 2007/01/04 02:39:53 cheshire
<rdar://problem/4030599> Hostname passed into DNSServiceRegister ignored for Wide-Area service registrations
Revision 1.316 2006/12/22 20:59:49 cheshire
<rdar://problem/4742742> Read *all* DNS keys from keychain,
not just key for the system-wide default registration domain
Revision 1.315 2006/12/20 04:07:35 cheshire
Remove uDNS_info substructure from AuthRecord_struct
Revision 1.314 2006/12/19 22:49:23 cheshire
Remove uDNS_info substructure from ServiceRecordSet_struct
Revision 1.313 2006/12/19 02:38:20 cheshire
Get rid of unnecessary duplicate query ID field from DNSQuestion_struct
Revision 1.312 2006/12/19 02:18:48 cheshire
Get rid of unnecessary duplicate "void *context" field from DNSQuestion_struct
Revision 1.311 2006/12/16 01:58:31 cheshire
<rdar://problem/4720673> uDNS: Need to start caching unicast records
Revision 1.310 2006/12/15 19:09:56 cheshire
<rdar://problem/4769083> ValidateRData() should be stricter about malformed MX and SRV records
Made DomainNameLength() more defensive by adding a limit parameter, so it can be
safely used to inspect potentially malformed data received from external sources.
Without this, a domain name that starts off apparently valid, but extends beyond the end of
the received packet data, could have appeared valid if the random bytes are already in memory
beyond the end of the packet just happened to have reasonable values (e.g. all zeroes).
Revision 1.309 2006/12/14 03:02:37 cheshire
<rdar://problem/4838433> Tools: dns-sd -G 0 only returns IPv6 when you have a routable IPv6 address
Revision 1.308 2006/11/30 23:07:56 herscher
<rdar://problem/4765644> uDNS: Sync up with Lighthouse changes for Private DNS
Revision 1.307 2006/11/18 05:01:30 cheshire
Preliminary support for unifying the uDNS and mDNS code,
including caching of uDNS answers
Revision 1.306 2006/11/10 07:44:04 herscher
<rdar://problem/4825493> Fix Daemon locking failures while toggling BTMM
Revision 1.305 2006/11/10 00:54:15 cheshire
<rdar://problem/4816598> Changing case of Computer Name doesn't work
Revision 1.304 2006/10/20 05:35:05 herscher
<rdar://problem/4720713> uDNS: Merge unicast active question list with multicast list.
Revision 1.303 2006/10/04 21:37:33 herscher
Remove uDNS_info substructure from DNSQuestion_struct
Revision 1.302 2006/09/26 01:53:25 herscher
<rdar://problem/4245016> NAT Port Mapping API (for both NAT-PMP and UPnP Gateway Protocol)
Revision 1.301 2006/09/15 21:20:15 cheshire
Remove uDNS_info substructure from mDNS_struct
Revision 1.300 2006/08/14 23:24:23 cheshire
Re-licensed mDNSResponder daemon source code under Apache License, Version 2.0
Revision 1.299 2006/07/15 02:01:28 cheshire
<rdar://problem/4472014> Add Private DNS client functionality to mDNSResponder
Fix broken "empty string" browsing
Revision 1.298 2006/07/05 22:55:03 cheshire
<rdar://problem/4472014> Add Private DNS client functionality to mDNSResponder
Need Private field in uDNS_RegInfo
Revision 1.297 2006/07/05 22:20:03 cheshire
<rdar://problem/4472014> Add Private DNS client functionality to mDNSResponder
Revision 1.296 2006/06/29 05:28:01 cheshire
Added comment about mDNSlocal and mDNSexport
Revision 1.295 2006/06/29 03:02:43 cheshire
<rdar://problem/4607042> mDNSResponder NXDOMAIN and CNAME support
Revision 1.294 2006/06/28 06:50:08 cheshire
In future we may want to change definition of mDNSs32 from "signed long" to "signed int"
I doubt anyone is building mDNSResponder on systems where int is 16-bits,
but lets add a compile-time assertion to make sure.
Revision 1.293 2006/06/12 18:00:43 cheshire
To make code a little more defensive, check _ILP64 before _LP64,
in case both are set by mistake on some platforms
Revision 1.292 2006/03/19 17:00:57 cheshire
Define symbol MaxMsg instead of using hard-coded constant value '80'
Revision 1.291 2006/03/19 02:00:07 cheshire
<rdar://problem/4073825> Improve logic for delaying packets after repeated interface transitions
Revision 1.290 2006/03/08 22:42:23 cheshire
Fix spelling mistake: LocalReverseMapomain -> LocalReverseMapDomain
Revision 1.289 2006/02/26 00:54:41 cheshire
Fixes to avoid code generation warning/error on FreeBSD 7
*/
#ifndef __mDNSClientAPI_h
#define __mDNSClientAPI_h
#if defined(EFI32) || defined(EFI64) || defined(EFIX64)
// EFI doesn't have stdarg.h unless it's building with GCC.
#include "Tiano.h"
#if !defined(__GNUC__)
#define va_list VA_LIST
#define va_start(a, b) VA_START(a, b)
#define va_end(a) VA_END(a)
#define va_arg(a, b) VA_ARG(a, b)
#endif
#else
#include <stdarg.h> // stdarg.h is required for for va_list support for the mDNS_vsnprintf declaration
#endif
#include "mDNSDebug.h"
#if APPLE_OSX_mDNSResponder
#include <uuid/uuid.h>
#endif
#ifdef __cplusplus
extern "C" {
#endif
// ***************************************************************************
// Function scope indicators
// If you see "mDNSlocal" before a function name in a C file, it means the function is not callable outside this file
#ifndef mDNSlocal
#define mDNSlocal static
#endif
// If you see "mDNSexport" before a symbol in a C file, it means the symbol is exported for use by clients
// For every "mDNSexport" in a C file, there needs to be a corresponding "extern" declaration in some header file
// (When a C file #includes a header file, the "extern" declarations tell the compiler:
// "This symbol exists -- but not necessarily in this C file.")
#ifndef mDNSexport
#define mDNSexport
#endif
// Explanation: These local/export markers are a little habit of mine for signaling the programmers' intentions.
// When "mDNSlocal" is just a synonym for "static", and "mDNSexport" is a complete no-op, you could be
// forgiven for asking what purpose they serve. The idea is that if you see "mDNSexport" in front of a
// function definition it means the programmer intended it to be exported and callable from other files
// in the project. If you see "mDNSlocal" in front of a function definition it means the programmer
// intended it to be private to that file. If you see neither in front of a function definition it
// means the programmer forgot (so you should work out which it is supposed to be, and fix it).
// Using "mDNSlocal" instead of "static" makes it easier to do a textual searches for one or the other.
// For example you can do a search for "static" to find if any functions declare any local variables as "static"
// (generally a bad idea unless it's also "const", because static storage usually risks being non-thread-safe)
// without the results being cluttered with hundreds of matches for functions declared static.
// - Stuart Cheshire
// ***************************************************************************
// Structure packing macro
// If we're not using GNUC, it's not fatal.
// Most compilers naturally pack the on-the-wire structures correctly anyway, so a plain "struct" is usually fine.
// In the event that structures are not packed correctly, mDNS_Init() will detect this and report an error, so the
// developer will know what's wrong, and can investigate what needs to be done on that compiler to provide proper packing.
#ifndef packedstruct
#if ((__GNUC__ > 2) || ((__GNUC__ == 2) && (__GNUC_MINOR__ >= 9)))
#define packedstruct struct __attribute__((__packed__))
#define packedunion union __attribute__((__packed__))
#else
#define packedstruct struct
#define packedunion union
#endif
#endif
// ***************************************************************************
#if 0
#pragma mark - DNS Resource Record class and type constants
#endif
typedef enum // From RFC 1035
{
kDNSClass_IN = 1, // Internet
kDNSClass_CS = 2, // CSNET
kDNSClass_CH = 3, // CHAOS
kDNSClass_HS = 4, // Hesiod
kDNSClass_NONE = 254, // Used in DNS UPDATE [RFC 2136]
kDNSClass_Mask = 0x7FFF,// Multicast DNS uses the bottom 15 bits to identify the record class...
kDNSClass_UniqueRRSet = 0x8000,// ... and the top bit indicates that all other cached records are now invalid
kDNSQClass_ANY = 255, // Not a DNS class, but a DNS query class, meaning "all classes"
kDNSQClass_UnicastResponse = 0x8000 // Top bit set in a question means "unicast response acceptable"
} DNS_ClassValues;
typedef enum // From RFC 1035
{
kDNSType_A = 1, // 1 Address
kDNSType_NS, // 2 Name Server
kDNSType_MD, // 3 Mail Destination
kDNSType_MF, // 4 Mail Forwarder
kDNSType_CNAME, // 5 Canonical Name
kDNSType_SOA, // 6 Start of Authority
kDNSType_MB, // 7 Mailbox
kDNSType_MG, // 8 Mail Group
kDNSType_MR, // 9 Mail Rename
kDNSType_NULL, // 10 NULL RR
kDNSType_WKS, // 11 Well-known-service
kDNSType_PTR, // 12 Domain name pointer
kDNSType_HINFO, // 13 Host information
kDNSType_MINFO, // 14 Mailbox information
kDNSType_MX, // 15 Mail Exchanger
kDNSType_TXT, // 16 Arbitrary text string
kDNSType_RP, // 17 Responsible person
kDNSType_AFSDB, // 18 AFS cell database
kDNSType_X25, // 19 X_25 calling address
kDNSType_ISDN, // 20 ISDN calling address
kDNSType_RT, // 21 Router
kDNSType_NSAP, // 22 NSAP address
kDNSType_NSAP_PTR, // 23 Reverse NSAP lookup (deprecated)
kDNSType_SIG, // 24 Security signature
kDNSType_KEY, // 25 Security key
kDNSType_PX, // 26 X.400 mail mapping
kDNSType_GPOS, // 27 Geographical position (withdrawn)
kDNSType_AAAA, // 28 IPv6 Address
kDNSType_LOC, // 29 Location Information
kDNSType_NXT, // 30 Next domain (security)
kDNSType_EID, // 31 Endpoint identifier
kDNSType_NIMLOC, // 32 Nimrod Locator
kDNSType_SRV, // 33 Service record
kDNSType_ATMA, // 34 ATM Address
kDNSType_NAPTR, // 35 Naming Authority PoinTeR
kDNSType_KX, // 36 Key Exchange
kDNSType_CERT, // 37 Certification record
kDNSType_A6, // 38 IPv6 Address (deprecated)
kDNSType_DNAME, // 39 Non-terminal DNAME (for IPv6)
kDNSType_SINK, // 40 Kitchen sink (experimental)
kDNSType_OPT, // 41 EDNS0 option (meta-RR)
kDNSType_APL, // 42 Address Prefix List
kDNSType_DS, // 43 Delegation Signer
kDNSType_SSHFP, // 44 SSH Key Fingerprint
kDNSType_IPSECKEY, // 45 IPSECKEY
kDNSType_RRSIG, // 46 RRSIG
kDNSType_NSEC, // 47 Denial of Existence
kDNSType_DNSKEY, // 48 DNSKEY
kDNSType_DHCID, // 49 DHCP Client Identifier
kDNSType_NSEC3, // 50 Hashed Authenticated Denial of Existence
kDNSType_NSEC3PARAM, // 51 Hashed Authenticated Denial of Existence
kDNSType_HIP = 55, // 55 Host Identity Protocol
kDNSType_SPF = 99, // 99 Sender Policy Framework for E-Mail
kDNSType_UINFO, // 100 IANA-Reserved
kDNSType_UID, // 101 IANA-Reserved
kDNSType_GID, // 102 IANA-Reserved
kDNSType_UNSPEC, // 103 IANA-Reserved
kDNSType_TKEY = 249, // 249 Transaction key
kDNSType_TSIG, // 250 Transaction signature
kDNSType_IXFR, // 251 Incremental zone transfer
kDNSType_AXFR, // 252 Transfer zone of authority
kDNSType_MAILB, // 253 Transfer mailbox records
kDNSType_MAILA, // 254 Transfer mail agent records
kDNSQType_ANY // Not a DNS type, but a DNS query type, meaning "all types"
} DNS_TypeValues;
// ***************************************************************************
#if 0
#pragma mark -
#pragma mark - Simple types
#endif
// mDNS defines its own names for these common types to simplify portability across
// multiple platforms that may each have their own (different) names for these types.
typedef int mDNSBool;
typedef signed char mDNSs8;
typedef unsigned char mDNSu8;
typedef signed short mDNSs16;
typedef unsigned short mDNSu16;
// <http://gcc.gnu.org/onlinedocs/gcc-3.3.3/cpp/Common-Predefined-Macros.html> says
// __LP64__ _LP64
// These macros are defined, with value 1, if (and only if) the compilation is
// for a target where long int and pointer both use 64-bits and int uses 32-bit.
// <http://www.intel.com/software/products/compilers/clin/docs/ug/lin1077.htm> says
// Macro Name __LP64__ Value 1
// A quick Google search for "defined(__LP64__)" OR "#ifdef __LP64__" gives 2590 hits and
// a search for "#if __LP64__" gives only 12, so I think we'll go with the majority and use defined()
#if defined(_ILP64) || defined(__ILP64__)
typedef signed int32 mDNSs32;
typedef unsigned int32 mDNSu32;
#elif defined(_LP64) || defined(__LP64__)
typedef signed int mDNSs32;
typedef unsigned int mDNSu32;
#else
typedef signed long mDNSs32;
typedef unsigned long mDNSu32;
//typedef signed int mDNSs32;
//typedef unsigned int mDNSu32;
#endif
// To enforce useful type checking, we make mDNSInterfaceID be a pointer to a dummy struct
// This way, mDNSInterfaceIDs can be assigned, and compared with each other, but not with other types
// Declaring the type to be the typical generic "void *" would lack this type checking
typedef struct mDNSInterfaceID_dummystruct { void *dummy; } *mDNSInterfaceID;
// These types are for opaque two- and four-byte identifiers.
// The "NotAnInteger" fields of the unions allow the value to be conveniently passed around in a
// register for the sake of efficiency, and compared for equality or inequality, but don't forget --
// just because it is in a register doesn't mean it is an integer. Operations like greater than,
// less than, add, multiply, increment, decrement, etc., are undefined for opaque identifiers,
// and if you make the mistake of trying to do those using the NotAnInteger field, then you'll
// find you get code that doesn't work consistently on big-endian and little-endian machines.
#if defined(_WIN32)
#pragma pack(push,2)
#endif
typedef union { mDNSu8 b[ 2]; mDNSu16 NotAnInteger; } mDNSOpaque16;
typedef union { mDNSu8 b[ 4]; mDNSu32 NotAnInteger; } mDNSOpaque32;
typedef packedunion { mDNSu8 b[ 6]; mDNSu16 w[3]; mDNSu32 l[1]; } mDNSOpaque48;
typedef union { mDNSu8 b[ 8]; mDNSu16 w[4]; mDNSu32 l[2]; } mDNSOpaque64;
typedef union { mDNSu8 b[16]; mDNSu16 w[8]; mDNSu32 l[4]; } mDNSOpaque128;
#if defined(_WIN32)
#pragma pack(pop)
#endif
typedef mDNSOpaque16 mDNSIPPort; // An IP port is a two-byte opaque identifier (not an integer)
typedef mDNSOpaque32 mDNSv4Addr; // An IP address is a four-byte opaque identifier (not an integer)
typedef mDNSOpaque128 mDNSv6Addr; // An IPv6 address is a 16-byte opaque identifier (not an integer)
typedef mDNSOpaque48 mDNSEthAddr; // An Ethernet address is a six-byte opaque identifier (not an integer)
enum
{
mDNSAddrType_None = 0,
mDNSAddrType_IPv4 = 4,
mDNSAddrType_IPv6 = 6,
mDNSAddrType_Unknown = ~0 // Special marker value used in known answer list recording
};
enum
{
mDNSTransport_None = 0,
mDNSTransport_UDP = 1,
mDNSTransport_TCP = 2
};
typedef struct
{
mDNSs32 type;
union { mDNSv6Addr v6; mDNSv4Addr v4; } ip;
} mDNSAddr;
enum { mDNSfalse = 0, mDNStrue = 1 };
#define mDNSNULL 0L
enum
{
mStatus_Waiting = 1,
mStatus_NoError = 0,
// mDNS return values are in the range FFFE FF00 (-65792) to FFFE FFFF (-65537)
// The top end of the range (FFFE FFFF) is used for error codes;
// the bottom end of the range (FFFE FF00) is used for non-error values;
// Error codes:
mStatus_UnknownErr = -65537, // First value: 0xFFFE FFFF
mStatus_NoSuchNameErr = -65538,
mStatus_NoMemoryErr = -65539,
mStatus_BadParamErr = -65540,
mStatus_BadReferenceErr = -65541,
mStatus_BadStateErr = -65542,
mStatus_BadFlagsErr = -65543,
mStatus_UnsupportedErr = -65544,
mStatus_NotInitializedErr = -65545,
mStatus_NoCache = -65546,
mStatus_AlreadyRegistered = -65547,
mStatus_NameConflict = -65548,
mStatus_Invalid = -65549,
mStatus_Firewall = -65550,
mStatus_Incompatible = -65551,
mStatus_BadInterfaceErr = -65552,
mStatus_Refused = -65553,
mStatus_NoSuchRecord = -65554,
mStatus_NoAuth = -65555,
mStatus_NoSuchKey = -65556,
mStatus_NATTraversal = -65557,
mStatus_DoubleNAT = -65558,
mStatus_BadTime = -65559,
mStatus_BadSig = -65560, // while we define this per RFC 2845, BIND 9 returns Refused for bad/missing signatures
mStatus_BadKey = -65561,
mStatus_TransientErr = -65562, // transient failures, e.g. sending packets shortly after a network transition or wake from sleep
mStatus_ServiceNotRunning = -65563, // Background daemon not running
mStatus_NATPortMappingUnsupported = -65564, // NAT doesn't support NAT-PMP or UPnP
mStatus_NATPortMappingDisabled = -65565, // NAT supports NAT-PMP or UPnP but it's disabled by the administrator
mStatus_NoRouter = -65566,
mStatus_PollingMode = -65567,
// -65568 to -65786 currently unused; available for allocation
// tcp connection status
mStatus_ConnPending = -65787,
mStatus_ConnFailed = -65788,
mStatus_ConnEstablished = -65789,
// Non-error values:
mStatus_GrowCache = -65790,
mStatus_ConfigChanged = -65791,
mStatus_MemFree = -65792 // Last value: 0xFFFE FF00
// mStatus_MemFree is the last legal mDNS error code, at the end of the range allocated for mDNS
};
typedef mDNSs32 mStatus;
// RFC 1034/1035 specify that a domain label consists of a length byte plus up to 63 characters
#define MAX_DOMAIN_LABEL 63
typedef struct { mDNSu8 c[ 64]; } domainlabel; // One label: length byte and up to 63 characters
// RFC 1034/1035/2181 specify that a domain name, including length bytes, data bytes, and terminating zero, may be up to 256 bytes long
#define MAX_DOMAIN_NAME 256
typedef struct { mDNSu8 c[256]; } domainname; // Up to 256 bytes of length-prefixed domainlabels
typedef struct { mDNSu8 c[256]; } UTF8str255; // Null-terminated C string
// The longest legal textual form of a DNS name is 1009 bytes, including the C-string terminating NULL at the end.
// Explanation:
// When a native domainname object is converted to printable textual form using ConvertDomainNameToCString(),
// non-printing characters are represented in the conventional DNS way, as '\ddd', where ddd is a three-digit decimal number.
// The longest legal domain name is 256 bytes, in the form of four labels as shown below:
// Length byte, 63 data bytes, length byte, 63 data bytes, length byte, 63 data bytes, length byte, 62 data bytes, zero byte.
// Each label is encoded textually as characters followed by a trailing dot.
// If every character has to be represented as a four-byte escape sequence, then this makes the maximum textual form four labels
// plus the C-string terminating NULL as shown below:
// 63*4+1 + 63*4+1 + 63*4+1 + 62*4+1 + 1 = 1009.
// Note that MAX_ESCAPED_DOMAIN_LABEL is not normally used: If you're only decoding a single label, escaping is usually not required.
// It is for domain names, where dots are used as label separators, that proper escaping is vital.
#define MAX_ESCAPED_DOMAIN_LABEL 254
#define MAX_ESCAPED_DOMAIN_NAME 1009
// MAX_REVERSE_MAPPING_NAME
// For IPv4: "123.123.123.123.in-addr.arpa." 30 bytes including terminating NUL
// 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
#define MAX_REVERSE_MAPPING_NAME_V4 30
#define MAX_REVERSE_MAPPING_NAME_V6 74
#define MAX_REVERSE_MAPPING_NAME 74
// Most records have a TTL of 75 minutes, so that their 80% cache-renewal query occurs once per hour.
// For records containing a hostname (in the name on the left, or in the rdata on the right),
// like A, AAAA, reverse-mapping PTR, and SRV, we use a two-minute TTL by default, because we don't want
// them to hang around for too long in the cache if the host in question crashes or otherwise goes away.
#define kStandardTTL (3600UL * 100 / 80)
#define kHostNameTTL 120UL
#define DefaultTTLforRRType(X) (((X) == kDNSType_A || (X) == kDNSType_AAAA || (X) == kDNSType_SRV) ? kHostNameTTL : kStandardTTL)
typedef struct AuthRecord_struct AuthRecord;
typedef struct ServiceRecordSet_struct ServiceRecordSet;
typedef struct CacheRecord_struct CacheRecord;
typedef struct CacheGroup_struct CacheGroup;
typedef struct DNSQuestion_struct DNSQuestion;
typedef struct ZoneData_struct ZoneData;
typedef struct mDNS_struct mDNS;
typedef struct mDNS_PlatformSupport_struct mDNS_PlatformSupport;
typedef struct NATTraversalInfo_struct NATTraversalInfo;
// Structure to abstract away the differences between TCP/SSL sockets, and one for UDP sockets
// The actual definition of these structures appear in the appropriate platform support code
typedef struct TCPSocket_struct TCPSocket;
typedef struct UDPSocket_struct UDPSocket;
// ***************************************************************************
#if 0
#pragma mark -
#pragma mark - DNS Message structures
#endif
#define mDNS_numZones numQuestions
#define mDNS_numPrereqs numAnswers
#define mDNS_numUpdates numAuthorities
typedef packedstruct
{
mDNSOpaque16 id;
mDNSOpaque16 flags;
mDNSu16 numQuestions;
mDNSu16 numAnswers;
mDNSu16 numAuthorities;
mDNSu16 numAdditionals;
} DNSMessageHeader;
// We can send and receive packets up to 9000 bytes (Ethernet Jumbo Frame size, if that ever becomes widely used)
// However, in the normal case we try to limit packets to 1500 bytes so that we don't get IP fragmentation on standard Ethernet
// 40 (IPv6 header) + 8 (UDP header) + 12 (DNS message header) + 1440 (DNS message body) = 1500 total
#define AbsoluteMaxDNSMessageData 8940
#define NormalMaxDNSMessageData 1440
typedef packedstruct
{
DNSMessageHeader h; // Note: Size 12 bytes
mDNSu8 data[AbsoluteMaxDNSMessageData]; // 40 (IPv6) + 8 (UDP) + 12 (DNS header) + 8940 (data) = 9000
} DNSMessage;
typedef struct tcpInfo_t
{
mDNS *m;
TCPSocket *sock;
DNSMessage request;
int requestLen;
DNSQuestion *question; // For queries
ServiceRecordSet *srs; // For service record updates
AuthRecord *rr; // For record updates
mDNSAddr Addr;
mDNSIPPort Port;
DNSMessage *reply;
mDNSu16 replylen;
unsigned long nread;
int numReplies;
} tcpInfo_t;
// ***************************************************************************
#if 0
#pragma mark -
#pragma mark - Other Packet Format Structures
#endif
typedef packedstruct
{
mDNSEthAddr dst;
mDNSEthAddr src;
mDNSOpaque16 ethertype;
} EthernetHeader; // 14 bytes
typedef packedstruct
{
mDNSOpaque16 hrd;
mDNSOpaque16 pro;
mDNSu8 hln;
mDNSu8 pln;
mDNSOpaque16 op;
mDNSEthAddr sha;
mDNSv4Addr spa;
mDNSEthAddr tha;
mDNSv4Addr tpa;
} ARP_EthIP; // 28 bytes
typedef packedstruct
{
mDNSu8 vlen;
mDNSu8 tos;
mDNSu16 totlen;
mDNSOpaque16 id;
mDNSOpaque16 flagsfrags;
mDNSu8 ttl;
mDNSu8 protocol;
mDNSu16 checksum;
mDNSv4Addr src;
mDNSv4Addr dst;
} IPv4Header; // 20 bytes
typedef packedstruct
{
mDNSu32 vcf; // Version, Traffic Class, Flow Label
mDNSu16 len; // Payload Length
mDNSu8 protocol; // Type of next header: 0x06 = TCP, 0x11 = UDP, 0x3A = ICMPv6
mDNSu8 ttl; // Hop Limit
mDNSv6Addr src;
mDNSv6Addr dst;
} IPv6Header; // 40 bytes
typedef packedstruct
{
mDNSu8 type; // 0x87 == Neighbor Solicitation, 0x88 == Neighbor Advertisement
mDNSu8 code;
mDNSu16 checksum;
mDNSu32 reserved;
mDNSv6Addr target;
} IPv6ND; // 24 bytes
typedef packedstruct
{
mDNSIPPort src;
mDNSIPPort dst;
mDNSu16 len; // Length including UDP header (ie. minimum value is 8 bytes)
mDNSu16 checksum;
} UDPHeader; // 8 bytes
typedef packedstruct
{
mDNSOpaque64 InitiatorCookie;
mDNSOpaque64 ResponderCookie;
mDNSu8 NextPayload;
mDNSu8 Version;
mDNSu8 ExchangeType;
mDNSu8 Flags;
mDNSOpaque32 MessageID;
mDNSu32 Length;
} IKEHeader; // 28 bytes
typedef packedstruct
{
mDNSIPPort src;
mDNSIPPort dst;
mDNSu32 seq;
mDNSu32 ack;
mDNSu8 offset;
mDNSu8 flags;
mDNSu16 window;
mDNSu16 checksum;
mDNSu16 urgent;
} TCPHeader; // 20 bytes
// ***************************************************************************
#if 0
#pragma mark -
#pragma mark - Resource Record structures
#endif
// Authoritative Resource Records:
// There are four basic types: Shared, Advisory, Unique, Known Unique
// * Shared Resource Records do not have to be unique
// -- Shared Resource Records are used for DNS-SD service PTRs
// -- It is okay for several hosts to have RRs with the same name but different RDATA
// -- We use a random delay on responses to reduce collisions when all the hosts respond to the same query
// -- These RRs typically have moderately high TTLs (e.g. one hour)
// -- These records are announced on startup and topology changes for the benefit of passive listeners
// -- These records send a goodbye packet when deregistering
//
// * Advisory Resource Records are like Shared Resource Records, except they don't send a goodbye packet
//
// * Unique Resource Records should be unique among hosts within any given mDNS scope
// -- The majority of Resource Records are of this type
// -- If two entities on the network have RRs with the same name but different RDATA, this is a conflict
// -- Responses may be sent immediately, because only one host should be responding to any particular query
// -- These RRs typically have low TTLs (e.g. a few minutes)
// -- On startup and after topology changes, a host issues queries to verify uniqueness
// * Known Unique Resource Records are treated like Unique Resource Records, except that mDNS does
// not have to verify their uniqueness because this is already known by other means (e.g. the RR name
// is derived from the host's IP or Ethernet address, which is already known to be a unique identifier).
// Summary of properties of different record types:
// Probe? Does this record type send probes before announcing?
// Conflict? Does this record type react if we observe an apparent conflict?
// Goodbye? Does this record type send a goodbye packet on departure?
//
// Probe? Conflict? Goodbye? Notes
// Unregistered Should not appear in any list (sanity check value)
// Shared No No Yes e.g. Service PTR record
// Deregistering No No Yes Shared record about to announce its departure and leave the list
// Advisory No No No
// Unique Yes Yes No Record intended to be unique -- will probe to verify
// Verified Yes Yes No Record has completed probing, and is verified unique
// KnownUnique No Yes No Record is assumed by other means to be unique
// Valid lifecycle of a record:
// Unregistered -> Shared -> Deregistering -(goodbye)-> Unregistered
// Unregistered -> Advisory -> Unregistered
// Unregistered -> Unique -(probe)-> Verified -> Unregistered
// Unregistered -> KnownUnique -> Unregistered
// Each Authoritative kDNSRecordType has only one bit set. This makes it easy to quickly see if a record
// is one of a particular set of types simply by performing the appropriate bitwise masking operation.
// Cache Resource Records (received from the network):
// There are four basic types: Answer, Unique Answer, Additional, Unique Additional
// Bit 7 (the top bit) of kDNSRecordType is always set for Cache Resource Records; always clear for Authoritative Resource Records
// Bit 6 (value 0x40) is set for answer records; clear for authority/additional records
// Bit 5 (value 0x20) is set for records received with the kDNSClass_UniqueRRSet
enum
{
kDNSRecordTypeUnregistered = 0x00, // Not currently in any list
kDNSRecordTypeDeregistering = 0x01, // Shared record about to announce its departure and leave the list
kDNSRecordTypeUnique = 0x02, // Will become a kDNSRecordTypeVerified when probing is complete
kDNSRecordTypeAdvisory = 0x04, // Like Shared, but no goodbye packet
kDNSRecordTypeShared = 0x08, // Shared means record name does not have to be unique -- use random delay on responses
kDNSRecordTypeVerified = 0x10, // Unique means mDNS should check that name is unique (and then send immediate responses)
kDNSRecordTypeKnownUnique = 0x20, // Known Unique means mDNS can assume name is unique without checking
// For Dynamic Update records, Known Unique means the record must already exist on the server.
kDNSRecordTypeUniqueMask = (kDNSRecordTypeUnique | kDNSRecordTypeVerified | kDNSRecordTypeKnownUnique),
kDNSRecordTypeActiveMask = (kDNSRecordTypeAdvisory | kDNSRecordTypeShared | kDNSRecordTypeVerified | kDNSRecordTypeKnownUnique),
kDNSRecordTypePacketAdd = 0x80, // Received in the Additional Section of a DNS Response
kDNSRecordTypePacketAddUnique = 0x90, // Received in the Additional Section of a DNS Response with kDNSClass_UniqueRRSet set
kDNSRecordTypePacketAuth = 0xA0, // Received in the Authorities Section of a DNS Response
kDNSRecordTypePacketAuthUnique = 0xB0, // Received in the Authorities Section of a DNS Response with kDNSClass_UniqueRRSet set
kDNSRecordTypePacketAns = 0xC0, // Received in the Answer Section of a DNS Response
kDNSRecordTypePacketAnsUnique = 0xD0, // Received in the Answer Section of a DNS Response with kDNSClass_UniqueRRSet set
kDNSRecordTypePacketNegative = 0xF0, // Pseudo-RR generated to cache non-existence results like NXDomain
kDNSRecordTypePacketUniqueMask = 0x10 // True for PacketAddUnique, PacketAnsUnique, PacketAuthUnique
};
typedef packedstruct { mDNSu16 priority; mDNSu16 weight; mDNSIPPort port; domainname target; } rdataSRV;
typedef packedstruct { mDNSu16 preference; domainname exchange; } rdataMX;
typedef packedstruct { domainname mbox; domainname txt; } rdataRP;
typedef packedstruct { mDNSu16 preference; domainname map822; domainname mapx400; } rdataPX;
typedef packedstruct
{
domainname mname;
domainname rname;
mDNSs32 serial; // Modular counter; increases when zone changes
mDNSu32 refresh; // Time in seconds that a slave waits after successful replication of the database before it attempts replication again
mDNSu32 retry; // Time in seconds that a slave waits after an unsuccessful replication attempt before it attempts replication again
mDNSu32 expire; // Time in seconds that a slave holds on to old data while replication attempts remain unsuccessful
mDNSu32 min; // Nominally the minimum record TTL for this zone, in seconds; also used for negative caching.
} rdataSOA;
// EDNS Option Code registrations are recorded in the "DNS EDNS0 Options" section of
// <http://www.iana.org/assignments/dns-parameters>
#define kDNSOpt_LLQ 1
#define kDNSOpt_Lease 2
#define kDNSOpt_NSID 3
#define kDNSOpt_Owner 4
typedef struct
{
mDNSu16 vers;
mDNSu16 llqOp;
mDNSu16 err; // Or UDP reply port, in setup request
// Note: In the in-memory form, there's typically a two-byte space here, so that the following 64-bit id is word-aligned
mDNSOpaque64 id;
mDNSu32 llqlease;
} LLQOptData;
typedef struct
{
mDNSu8 vers; // Version number of this Owner OPT record
mDNSs8 seq; // Sleep/wake epoch
mDNSEthAddr HMAC; // Host's primary identifier (e.g. MAC of on-board Ethernet)
mDNSEthAddr IMAC; // Interface's MAC address (if different to primary MAC)
mDNSOpaque48 password; // Optional password
} OwnerOptData;
// Note: rdataOPT format may be repeated an arbitrary number of times in a single resource record
typedef packedstruct
{
mDNSu16 opt;
mDNSu16 optlen;
union { LLQOptData llq; mDNSu32 updatelease; OwnerOptData owner; } u;
} rdataOPT;
// Space needed to put OPT records into a packet:
// Header 11 bytes (name 1, type 2, class 2, TTL 4, length 2)
// LLQ rdata 18 bytes (opt 2, len 2, vers 2, op 2, err 2, id 8, lease 4)
// Lease rdata 8 bytes (opt 2, len 2, lease 4)
// Owner rdata 12-24 (opt 2, len 2, owner 8-20)
#define DNSOpt_Header_Space 11
#define DNSOpt_LLQData_Space (4 + 2 + 2 + 2 + 8 + 4)
#define DNSOpt_LeaseData_Space (4 + 4)
#define DNSOpt_OwnerData_ID_Space (4 + 2 + 6)
#define DNSOpt_OwnerData_ID_Wake_Space (4 + 2 + 6 + 6)
#define DNSOpt_OwnerData_ID_Wake_PW4_Space (4 + 2 + 6 + 6 + 4)
#define DNSOpt_OwnerData_ID_Wake_PW6_Space (4 + 2 + 6 + 6 + 6)
#define ValidOwnerLength(X) ( (X) == DNSOpt_OwnerData_ID_Space - 4 || \
(X) == DNSOpt_OwnerData_ID_Wake_Space - 4 || \
(X) == DNSOpt_OwnerData_ID_Wake_PW4_Space - 4 || \
(X) == DNSOpt_OwnerData_ID_Wake_PW6_Space - 4 )
#define ValidDNSOpt(O) (((O)->opt == kDNSOpt_LLQ && (O)->optlen == DNSOpt_LLQData_Space - 4) || \
((O)->opt == kDNSOpt_Lease && (O)->optlen == DNSOpt_LeaseData_Space - 4) || \
((O)->opt == kDNSOpt_Owner && ValidOwnerLength((O)->optlen) ) )
#define DNSOpt_Owner_Space(A,B) (mDNSSameEthAddress((A),(B)) ? DNSOpt_OwnerData_ID_Space : DNSOpt_OwnerData_ID_Wake_Space)
#define DNSOpt_Data_Space(O) ( \
(O)->opt == kDNSOpt_LLQ ? DNSOpt_LLQData_Space : \
(O)->opt == kDNSOpt_Lease ? DNSOpt_LeaseData_Space : \
(O)->opt == kDNSOpt_Owner ? DNSOpt_Owner_Space(&(O)->u.owner.HMAC, &(O)->u.owner.IMAC) : 0x10000)
// A maximal NSEC record is:
// 256 bytes domainname 'nextname'
// + 256 * 34 = 8704 bytes of bitmap data
// = 8960 bytes total
// 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),
// which gives us a fixed in-memory size of 32 bytes (256 bits)
typedef struct
{
mDNSu8 bitmap[32];
} rdataNSEC;
// StandardAuthRDSize is 264 (256+8), which is large enough to hold a maximum-sized SRV record (6 + 256 bytes)
// MaximumRDSize is 8K the absolute maximum we support (at least for now)
#define StandardAuthRDSize 264
#define MaximumRDSize 8192
// InlineCacheRDSize is 68
// Records received from the network with rdata this size or less have their rdata stored right in the CacheRecord object
// Records received from the network with rdata larger than this have additional storage allocated for the rdata
// A quick unscientific sample from a busy network at Apple with lots of machines revealed this:
// 1461 records in cache
// 292 were one-byte TXT records
// 136 were four-byte A records
// 184 were sixteen-byte AAAA records
// 780 were various PTR, TXT and SRV records from 12-64 bytes
// Only 69 records had rdata bigger than 64 bytes
// Note that since CacheRecord object and a CacheGroup object are allocated out of the same pool, it's sensible to
// have them both be the same size. Making one smaller without making the other smaller won't actually save any memory.
#define InlineCacheRDSize 68
// On 64-bit, the pointers in a CacheRecord are bigger, and that creates 8 bytes more space for the name in a CacheGroup
#if ENABLE_MULTI_PACKET_QUERY_SNOOPING
#if defined(_ILP64) || defined(__ILP64__) || defined(_LP64) || defined(__LP64__) || defined(_WIN64)
#define InlineCacheGroupNameSize 152
#else
#define InlineCacheGroupNameSize 144
#endif
#else
#if defined(_ILP64) || defined(__ILP64__) || defined(_LP64) || defined(__LP64__) || defined(_WIN64)
#define InlineCacheGroupNameSize 136
#else
#define InlineCacheGroupNameSize 128
#endif
#endif
// The RDataBody union defines the common rdata types that fit into our 264-byte limit
typedef union
{
mDNSu8 data[StandardAuthRDSize];
mDNSv4Addr ipv4; // For 'A' record
domainname name; // For PTR, NS, CNAME, DNAME
UTF8str255 txt;
rdataMX mx;
mDNSv6Addr ipv6; // For 'AAAA' record
rdataSRV srv;
rdataOPT opt[2]; // For EDNS0 OPT record; RDataBody may contain multiple variable-length rdataOPT objects packed together
rdataNSEC nsec;
} RDataBody;
// The RDataBody2 union is the same as above, except it includes fields for the larger types like soa, rp, px
typedef union
{
mDNSu8 data[StandardAuthRDSize];
mDNSv4Addr ipv4; // For 'A' record
domainname name; // For PTR, NS, CNAME, DNAME
rdataSOA soa; // This is large; not included in the normal RDataBody definition
UTF8str255 txt;
rdataMX mx;
rdataRP rp; // This is large; not included in the normal RDataBody definition
rdataPX px; // This is large; not included in the normal RDataBody definition
mDNSv6Addr ipv6; // For 'AAAA' record
rdataSRV srv;
rdataOPT opt[2]; // For EDNS0 OPT record; RDataBody may contain multiple variable-length rdataOPT objects packed together
rdataNSEC nsec;
} RDataBody2;
typedef struct
{
mDNSu16 MaxRDLength; // Amount of storage allocated for rdata (usually sizeof(RDataBody))
mDNSu16 padding; // So that RDataBody is aligned on 32-bit boundary
RDataBody u;
} RData;
// sizeofRDataHeader should be 4 bytes
#define sizeofRDataHeader (sizeof(RData) - sizeof(RDataBody))
// RData_small is a smaller version of the RData object, used for inline data storage embedded in a CacheRecord_struct
typedef struct
{
mDNSu16 MaxRDLength; // Storage allocated for data (may be greater than InlineCacheRDSize if additional storage follows this object)
mDNSu16 padding; // So that data is aligned on 32-bit boundary
mDNSu8 data[InlineCacheRDSize];
} RData_small;
// Note: Within an mDNSRecordCallback mDNS all API calls are legal except mDNS_Init(), mDNS_Exit(), mDNS_Execute()
typedef void mDNSRecordCallback(mDNS *const m, AuthRecord *const rr, mStatus result);
// Note:
// Restrictions: An mDNSRecordUpdateCallback may not make any mDNS API calls.
// The intent of this callback is to allow the client to free memory, if necessary.
// The internal data structures of the mDNS code may not be in a state where mDNS API calls may be made safely.
typedef void mDNSRecordUpdateCallback(mDNS *const m, AuthRecord *const rr, RData *OldRData);
// ***************************************************************************
#if 0
#pragma mark -
#pragma mark - NAT Traversal structures and constants
#endif
#define NATMAP_MAX_RETRY_INTERVAL ((mDNSPlatformOneSecond * 60) * 15) // Max retry interval is 15 minutes
#define NATMAP_MIN_RETRY_INTERVAL (mDNSPlatformOneSecond * 2) // Min retry interval is 2 seconds
#define NATMAP_INIT_RETRY (mDNSPlatformOneSecond / 4) // start at 250ms w/ exponential decay
#define NATMAP_DEFAULT_LEASE (60 * 60 * 2) // 2 hour lease life in seconds
#define NATMAP_VERS 0
typedef enum
{
NATOp_AddrRequest = 0,
NATOp_MapUDP = 1,
NATOp_MapTCP = 2,
NATOp_AddrResponse = 0x80 | 0,
NATOp_MapUDPResponse = 0x80 | 1,
NATOp_MapTCPResponse = 0x80 | 2,
} NATOp_t;
enum
{
NATErr_None = 0,
NATErr_Vers = 1,
NATErr_Refused = 2,
NATErr_NetFail = 3,
NATErr_Res = 4,
NATErr_Opcode = 5
};
typedef mDNSu16 NATErr_t;
typedef packedstruct
{
mDNSu8 vers;
mDNSu8 opcode;
} NATAddrRequest;
typedef packedstruct
{
mDNSu8 vers;
mDNSu8 opcode;
mDNSu16 err;
mDNSu32 upseconds; // Time since last NAT engine reboot, in seconds
mDNSv4Addr ExtAddr;
} NATAddrReply;
typedef packedstruct
{
mDNSu8 vers;
mDNSu8 opcode;
mDNSOpaque16 unused;
mDNSIPPort intport;
mDNSIPPort extport;
mDNSu32 NATReq_lease;
} NATPortMapRequest;
typedef packedstruct
{
mDNSu8 vers;
mDNSu8 opcode;
mDNSu16 err;
mDNSu32 upseconds; // Time since last NAT engine reboot, in seconds
mDNSIPPort intport;
mDNSIPPort extport;
mDNSu32 NATRep_lease;
} NATPortMapReply;
typedef enum
{
LNTDiscoveryOp = 1,
LNTExternalAddrOp = 2,
LNTPortMapOp = 3,
LNTPortMapDeleteOp = 4
} LNTOp_t;
#define LNT_MAXBUFSIZE 8192
typedef struct tcpLNTInfo_struct tcpLNTInfo;
struct tcpLNTInfo_struct
{
tcpLNTInfo *next;
mDNS *m;
NATTraversalInfo *parentNATInfo; // pointer back to the parent NATTraversalInfo
TCPSocket *sock;
LNTOp_t op; // operation performed using this connection
mDNSAddr Address; // router address
mDNSIPPort Port; // router port
mDNSs8 *Request; // xml request to router
int requestLen;
mDNSs8 *Reply; // xml reply from router
int replyLen;
unsigned long nread; // number of bytes read so far
int retries; // number of times we've tried to do this port mapping
};
typedef void (*NATTraversalClientCallback)(mDNS *m, NATTraversalInfo *n);
// if m->timenow < ExpiryTime then we have an active mapping, and we'll renew halfway to expiry
// if m->timenow >= ExpiryTime then our mapping has expired, and we're trying to create one
struct NATTraversalInfo_struct
{
// Internal state fields. These are used internally by mDNSCore; the client layer needn't be concerned with them.
NATTraversalInfo *next;
mDNSs32 ExpiryTime; // Time this mapping expires, or zero if no mapping
mDNSs32 retryInterval; // Current interval, between last packet we sent and the next one
mDNSs32 retryPortMap; // If Protocol is nonzero, time to send our next mapping packet
mStatus NewResult; // New error code; will be copied to Result just prior to invoking callback
#ifdef _LEGACY_NAT_TRAVERSAL_
tcpLNTInfo tcpInfo; // Legacy NAT traversal (UPnP) TCP connection
#endif
// Result fields: When the callback is invoked these fields contain the answers the client is looking for
// When the callback is invoked ExternalPort is *usually* set to be the same the same as RequestedPort, except:
// (a) When we're behind a NAT gateway with port mapping disabled, ExternalPort is reported as zero to
// indicate that we don't currently have a working mapping (but RequestedPort retains the external port
// we'd like to get, the next time we meet an accomodating NAT gateway willing to give us one).
// (b) When we have a routable non-RFC1918 address, we don't *need* a port mapping, so ExternalPort
// is reported as the same as our InternalPort, since that is effectively our externally-visible port too.
// Again, RequestedPort retains the external port we'd like to get the next time we find ourself behind a NAT gateway.
// To improve stability of port mappings, RequestedPort is updated any time we get a successful
// mapping response from the NAT-PMP or UPnP gateway. For example, if we ask for port 80, and
// get assigned port 81, then thereafter we'll contine asking for port 81.
mDNSInterfaceID InterfaceID;
mDNSv4Addr ExternalAddress; // Initially set to onesIPv4Addr, until first callback
mDNSIPPort ExternalPort;
mDNSu32 Lifetime;
mStatus Result;
// Client API fields: The client must set up these fields *before* making any NAT traversal API calls
mDNSu8 Protocol; // NATOp_MapUDP or NATOp_MapTCP, or zero if just requesting the external IP address
mDNSIPPort IntPort; // Client's internal port number (doesn't change)
mDNSIPPort RequestedPort; // Requested external port; may be updated with actual value assigned by gateway
mDNSu32 NATLease; // Requested lifetime in seconds (doesn't change)
NATTraversalClientCallback clientCallback;
void *clientContext;
};
typedef struct // Size is 36 bytes when compiling for 32-bit; 48 when compiling for 64-bit
{
mDNSu8 RecordType; // See enum above
mDNSu16 rrtype;
mDNSu16 rrclass;
mDNSu32 rroriginalttl; // In seconds
mDNSu16 rdlength; // Size of the raw rdata, in bytes, in the on-the-wire format
// (In-memory storage may be larger, for structures containing 'holes', like SOA,
// or smaller, for NSEC where we don't bother storing the nextname field)
mDNSu16 rdestimate; // Upper bound on on-the-wire size of rdata after name compression
mDNSu32 namehash; // Name-based (i.e. case-insensitive) hash of name
mDNSu32 rdatahash; // For rdata containing domain name (e.g. PTR, SRV, CNAME etc.), case-insensitive name hash
// else, for all other rdata, 32-bit hash of the raw rdata
// Note: This requirement is important. Various routines like AddAdditionalsToResponseList(),
// ReconfirmAntecedents(), etc., use rdatahash as a pre-flight check to see
// whether it's worth doing a full SameDomainName() call. If the rdatahash
// is not a correct case-insensitive name hash, they'll get false negatives.
// Grouping pointers together at the end of the structure improves the memory layout efficiency
mDNSInterfaceID InterfaceID; // Set if this RR is specific to one interface
// For records received off the wire, InterfaceID is *always* set to the receiving interface
// For our authoritative records, InterfaceID is usually zero, except for those few records
// that are interface-specific (e.g. address records, especially linklocal addresses)
const domainname *name;
RData *rdata; // Pointer to storage for this rdata
} ResourceRecord;
// Unless otherwise noted, states may apply to either independent record registrations or service registrations
typedef enum
{
regState_Zero = 0,
regState_FetchingZoneData = 1, // getting info - update not sent
regState_Pending = 2, // update sent, reply not received
regState_Registered = 3, // update sent, reply received
regState_DeregPending = 4, // dereg sent, reply not received
regState_DeregDeferred = 5, // dereg requested while in Pending state - send dereg AFTER registration is confirmed
regState_Unregistered = 8, // not in any list
regState_Refresh = 9, // outstanding refresh (or target change) message
regState_NATMap = 10, // establishing NAT port mapping (service registrations only)
regState_UpdatePending = 11, // update in flight as result of mDNS_Update call
regState_NoTarget = 12, // service registration pending registration of hostname (ServiceRegistrations only)
regState_ExtraQueued = 13, // extra record to be registered upon completion of service registration (RecordRegistrations only)
regState_NATError = 14 // unable to complete NAT traversal
} regState_t;
enum
{
Target_Manual = 0,
Target_AutoHost = 1,
Target_AutoHostAndNATMAP = 2
};
struct AuthRecord_struct
{
// For examples of how to set up this structure for use in mDNS_Register(),
// see mDNS_AdvertiseInterface() or mDNS_RegisterService().
// Basically, resrec and persistent metadata need to be set up before calling mDNS_Register().
// mDNS_SetupResourceRecord() is avaliable as a helper routine to set up most fields to sensible default values for you
AuthRecord *next; // Next in list; first element of structure for efficiency reasons
// Field Group 1: Common ResourceRecord fields
ResourceRecord resrec; // 36 bytes when compiling for 32-bit; 48 when compiling for 64-bit
// Field Group 2: Persistent metadata for Authoritative Records
AuthRecord *Additional1; // Recommended additional record to include in response (e.g. SRV for PTR record)
AuthRecord *Additional2; // Another additional (e.g. TXT for PTR record)
AuthRecord *DependentOn; // This record depends on another for its uniqueness checking
AuthRecord *RRSet; // This unique record is part of an RRSet
mDNSRecordCallback *RecordCallback; // Callback function to call for state changes, and to free memory asynchronously on deregistration
void *RecordContext; // Context parameter for the callback function
mDNSu8 AutoTarget; // Set if the target of this record (PTR, CNAME, SRV, etc.) is our host name
mDNSu8 AllowRemoteQuery; // Set if we allow hosts not on the local link to query this record
mDNSu8 ForceMCast; // Set by client to advertise solely via multicast, even for apparently unicast names
OwnerOptData WakeUp; // Fpr Sleep Proxy records, MAC address of original owner (so we can wake it)
mDNSAddr AddressProxy; // For reverse-mapping Sleep Proxy PTR records, address in question
mDNSs32 TimeRcvd; // In platform time units
mDNSs32 TimeExpire; // In platform time units
// Field Group 3: Transient state for Authoritative Records
mDNSu8 Acknowledged; // Set if we've given the success callback to the client
mDNSu8 ProbeCount; // Number of probes remaining before this record is valid (kDNSRecordTypeUnique)
mDNSu8 AnnounceCount; // Number of announcements remaining (kDNSRecordTypeShared)
mDNSu8 RequireGoodbye; // Set if this RR has been announced on the wire and will require a goodbye packet
mDNSu8 AnsweredLocalQ; // Set if this AuthRecord has been delivered to any local question (LocalOnly or mDNSInterface_Any)
mDNSu8 IncludeInProbe; // Set if this RR is being put into a probe right now
mDNSu8 ImmedUnicast; // Set if we may send our response directly via unicast to the requester
mDNSInterfaceID SendNSECNow; // Set if we need to generate associated NSEC data for this rrname
mDNSInterfaceID ImmedAnswer; // Someone on this interface issued a query we need to answer (all-ones for all interfaces)
#if MDNS_LOG_ANSWER_SUPPRESSION_TIMES
mDNSs32 ImmedAnswerMarkTime;
#endif
mDNSInterfaceID ImmedAdditional; // Hint that we might want to also send this record, just to be helpful
mDNSInterfaceID SendRNow; // The interface this query is being sent on right now
mDNSv4Addr v4Requester; // Recent v4 query for this record, or all-ones if more than one recent query
mDNSv6Addr v6Requester; // Recent v6 query for this record, or all-ones if more than one recent query
AuthRecord *NextResponse; // Link to the next element in the chain of responses to generate
const mDNSu8 *NR_AnswerTo; // Set if this record was selected by virtue of being a direct answer to a question
AuthRecord *NR_AdditionalTo; // Set if this record was selected by virtue of being additional to another
mDNSs32 ThisAPInterval; // In platform time units: Current interval for announce/probe
mDNSs32 LastAPTime; // In platform time units: Last time we sent announcement/probe
mDNSs32 LastMCTime; // Last time we multicast this record (used to guard against packet-storm attacks)
mDNSInterfaceID LastMCInterface; // Interface this record was multicast on at the time LastMCTime was recorded
RData *NewRData; // Set if we are updating this record with new rdata
mDNSu16 newrdlength; // ... and the length of the new RData
mDNSRecordUpdateCallback *UpdateCallback;
mDNSu32 UpdateCredits; // Token-bucket rate limiting of excessive updates
mDNSs32 NextUpdateCredit; // Time next token is added to bucket
mDNSs32 UpdateBlocked; // Set if update delaying is in effect
// Field Group 4: Transient uDNS state for Authoritative Records
regState_t state; // Maybe combine this with resrec.RecordType state? Right now it's ambiguous and confusing.
// e.g. rr->resrec.RecordType can be kDNSRecordTypeUnregistered,
// and rr->state can be regState_Unregistered
// What if we find one of those statements is true and the other false? What does that mean?
mDNSBool uselease; // dynamic update contains (should contain) lease option
mDNSs32 expire; // In platform time units: expiration of lease (-1 for static)
mDNSBool Private; // If zone is private, DNS updates may have to be encrypted to prevent eavesdropping
mDNSOpaque16 updateid; // Identifier to match update request and response -- also used when transferring records to Sleep Proxy
const domainname *zone; // the zone that is updated
mDNSAddr UpdateServer; // DNS server that handles updates for this zone
mDNSIPPort UpdatePort; // port on which server accepts dynamic updates
// !!!KRS not technically correct to cache longer than TTL
// SDC Perhaps should keep a reference to the relevant SRV record in the cache?
ZoneData *nta;
struct tcpInfo_t *tcp;
// uDNS_UpdateRecord support fields
// Do we really need all these in *addition* to NewRData and newrdlength above?
mDNSu16 OrigRDLen; // previously registered, being deleted
mDNSu16 InFlightRDLen; // currently being registered
mDNSu16 QueuedRDLen; // pending operation (re-transmitting if necessary) THEN register the queued update
RData *OrigRData;
RData *InFlightRData;
RData *QueuedRData;
// Field Group 5: Large data objects go at the end
domainname namestorage;
RData rdatastorage; // Normally the storage is right here, except for oversized records
// rdatastorage MUST be the last thing in the structure -- when using oversized AuthRecords, extra bytes
// are appended after the end of the AuthRecord, logically augmenting the size of the rdatastorage
// DO NOT ADD ANY MORE FIELDS HERE
};
#define AuthRecord_uDNS(R) ((R)->resrec.InterfaceID == mDNSInterface_Any && !(R)->ForceMCast && !IsLocalDomain((R)->resrec.name))
#define Question_uDNS(Q) ((Q)->InterfaceID == mDNSInterface_Any && !(Q)->ForceMCast && !IsLocalDomain(&(Q)->qname))
// Wrapper struct for Auth Records for higher-level code that cannot use the AuthRecord's ->next pointer field
typedef struct ARListElem
{
struct ARListElem *next;
AuthRecord ar; // Note: Must be last element of structure, to accomodate oversized AuthRecords
} ARListElem;
struct CacheGroup_struct // Header object for a list of CacheRecords with the same name
{
CacheGroup *next; // Next CacheGroup object in this hash table bucket
mDNSu32 namehash; // Name-based (i.e. case insensitive) hash of name
CacheRecord *members; // List of CacheRecords with this same name
CacheRecord **rrcache_tail; // Tail end of that list
domainname *name; // Common name for all CacheRecords in this list
// Size to here is 20 bytes when compiling 32-bit; 40 bytes when compiling 64-bit
mDNSu8 namestorage[InlineCacheGroupNameSize];
};
struct CacheRecord_struct
{
CacheRecord *next; // Next in list; first element of structure for efficiency reasons
ResourceRecord resrec; // 36 bytes when compiling for 32-bit; 48 when compiling for 64-bit
// Transient state for Cache Records
CacheRecord *NextInKAList; // Link to the next element in the chain of known answers to send
mDNSs32 TimeRcvd; // In platform time units
mDNSs32 DelayDelivery; // Set if we want to defer delivery of this answer to local clients
mDNSs32 NextRequiredQuery; // In platform time units
mDNSs32 LastUsed; // In platform time units
DNSQuestion *CRActiveQuestion; // Points to an active question referencing this answer
mDNSu32 UnansweredQueries; // Number of times we've issued a query for this record without getting an answer
mDNSs32 LastUnansweredTime; // In platform time units; last time we incremented UnansweredQueries
#if ENABLE_MULTI_PACKET_QUERY_SNOOPING
mDNSu32 MPUnansweredQ; // Multi-packet query handling: Number of times we've seen a query for this record
mDNSs32 MPLastUnansweredQT; // Multi-packet query handling: Last time we incremented MPUnansweredQ
mDNSu32 MPUnansweredKA; // Multi-packet query handling: Number of times we've seen this record in a KA list
mDNSBool MPExpectingKA; // Multi-packet query handling: Set when we increment MPUnansweredQ; allows one KA
#endif
CacheRecord *NextInCFList; // Set if this is in the list of records we just received with the cache flush bit set
// Size to here is 76 bytes when compiling 32-bit; 104 bytes when compiling 64-bit
RData_small smallrdatastorage; // Storage for small records is right here (4 bytes header + 68 bytes data = 72 bytes)
};
// Storage sufficient to hold either a CacheGroup header or a CacheRecord
// -- for best efficiency (to avoid wasted unused storage) they should be the same size
typedef union CacheEntity_union CacheEntity;
union CacheEntity_union { CacheEntity *next; CacheGroup cg; CacheRecord cr; };
typedef struct
{
CacheRecord r;
mDNSu8 _extradata[MaximumRDSize-InlineCacheRDSize]; // Glue on the necessary number of extra bytes
domainname namestorage; // Needs to go *after* the extra rdata bytes
} LargeCacheRecord;
typedef struct HostnameInfo
{
struct HostnameInfo *next;
NATTraversalInfo natinfo;
domainname fqdn;
AuthRecord arv4; // registered IPv4 address record
AuthRecord arv6; // registered IPv6 address record
mDNSRecordCallback *StatusCallback; // callback to deliver success or error code to client layer
const void *StatusContext; // Client Context
} HostnameInfo;
enum
{
DNSServer_Untested = 0,
DNSServer_Passed = 1,
DNSServer_Failed = 2,
DNSServer_Disabled = 3
};
enum
{
DNSServer_FlagDelete = 1,
DNSServer_FlagNew = 2
};
typedef struct DNSServer
{
struct DNSServer *next;
mDNSInterfaceID interface; // For specialized uses; we can have DNS servers reachable over specific interfaces
mDNSAddr addr;
mDNSIPPort port;
mDNSOpaque16 testid;
mDNSu32 flags; // Set when we're planning to delete this from the list
mDNSu32 teststate; // Have we sent bug-detection query to this server?
mDNSs32 lasttest; // Time we sent last bug-detection query to this server
domainname domain; // name->server matching for "split dns"
mDNSs32 penaltyTime; // amount of time this server is penalized
} DNSServer;
typedef struct ExtraResourceRecord_struct ExtraResourceRecord;
struct ExtraResourceRecord_struct
{
ExtraResourceRecord *next;
mDNSu32 ClientID; // Opaque ID field to be used by client to map an AddRecord call to a set of Extra records
AuthRecord r;
// Note: Add any additional fields *before* the AuthRecord in this structure, not at the end.
// In some cases clients can allocate larger chunks of memory and set r->rdata->MaxRDLength to indicate
// that this extra memory is available, which would result in any fields after the AuthRecord getting smashed
};
// Note: Within an mDNSServiceCallback mDNS all API calls are legal except mDNS_Init(), mDNS_Exit(), mDNS_Execute()
typedef void mDNSServiceCallback(mDNS *const m, ServiceRecordSet *const sr, mStatus result);
// A ServiceRecordSet is basically a convenience structure to group together
// the PTR/SRV/TXT records that make up a standard service registration
// It contains its own ServiceCallback+ServiceContext to report aggregate results up to the next layer of software above
// It also contains:
// * the "_services" PTR record for service enumeration
// * the optional target host name (for proxy registrations)
// * the optional list of SubType PTR records
// * the optional list of additional records attached to the service set (e.g. iChat pictures)
//
// ... and a bunch of stuff related to uDNS, some of which could be simplified or eliminated
struct ServiceRecordSet_struct
{
// These internal state fields are used internally by mDNSCore; the client layer needn't be concerned with them.
// No fields need to be set up by the client prior to calling mDNS_RegisterService();
// all required data is passed as parameters to that function.
// Begin uDNS info ****************
// All of these fields should be eliminated
// Note: The current uDNS code keeps an explicit list of registered services, and handles them
// differently to how individual records are treated (this is probably a mistake). What this means is
// that ServiceRecordSets for uDNS are kept in a linked list, whereas ServiceRecordSets for mDNS exist
// just as a convenient placeholder to group the component records together and are not kept on any list.
ServiceRecordSet *uDNS_next;
regState_t state;
mDNSBool srs_uselease; // dynamic update contains (should contain) lease option
mDNSBool TestForSelfConflict; // on name conflict, check if we're just seeing our own orphaned records
mDNSBool Private; // If zone is private, DNS updates may have to be encrypted to prevent eavesdropping
ZoneData *srs_nta;
mDNSOpaque16 id;
domainname zone; // the zone that is updated
mDNSAddr SRSUpdateServer; // primary name server for the record's zone !!!KRS not technically correct to cache longer than TTL
mDNSIPPort SRSUpdatePort; // port on which server accepts dynamic updates
NATTraversalInfo NATinfo;
mDNSBool ClientCallbackDeferred; // invoke client callback on completion of pending operation(s)
mStatus DeferredStatus; // status to deliver when above flag is set
mDNSBool SRVUpdateDeferred; // do we need to change target or port once current operation completes?
mDNSBool SRVChanged; // temporarily deregistered service because its SRV target or port changed
struct tcpInfo_t *tcp;
// End uDNS info ****************
mDNSServiceCallback *ServiceCallback;
void *ServiceContext;
mDNSBool Conflict; // Set if this record set was forcibly deregistered because of a conflict
ExtraResourceRecord *Extras; // Optional list of extra AuthRecords attached to this service registration
mDNSu32 NumSubTypes;
AuthRecord *SubTypes;
AuthRecord RR_ADV; // e.g. _services._dns-sd._udp.local. PTR _printer._tcp.local.
AuthRecord RR_PTR; // e.g. _printer._tcp.local. PTR Name._printer._tcp.local.
AuthRecord RR_SRV; // e.g. Name._printer._tcp.local. SRV 0 0 port target
AuthRecord RR_TXT; // e.g. Name._printer._tcp.local. TXT PrintQueueName
// Don't add any fields after AuthRecord RR_TXT.
// This is where the implicit extra space goes if we allocate a ServiceRecordSet containing an oversized RR_TXT record
};
// ***************************************************************************
#if 0
#pragma mark -
#pragma mark - Question structures
#endif
// We record the last eight instances of each duplicate query
// This gives us v4/v6 on each of Ethernet/AirPort and Firewire, and two free slots "for future expansion"
// If the host has more active interfaces that this it is not fatal -- duplicate question suppression will degrade gracefully.
// Since we will still remember the last eight, the busiest interfaces will still get the effective duplicate question suppression.
#define DupSuppressInfoSize 8
typedef struct
{
mDNSs32 Time;
mDNSInterfaceID InterfaceID;
mDNSs32 Type; // v4 or v6?
} DupSuppressInfo;
typedef enum
{
LLQ_InitialRequest = 1,
LLQ_SecondaryRequest = 2,
LLQ_Established = 3,
LLQ_Poll = 4
} LLQ_State;
// LLQ constants
#define kLLQ_Vers 1
#define kLLQ_DefLease 7200 // 2 hours
#define kLLQ_MAX_TRIES 3 // retry an operation 3 times max
#define kLLQ_INIT_RESEND 2 // resend an un-ack'd packet after 2 seconds, then double for each additional
// LLQ Operation Codes
#define kLLQOp_Setup 1
#define kLLQOp_Refresh 2
#define kLLQOp_Event 3
// LLQ Errror Codes
enum
{
LLQErr_NoError = 0,
LLQErr_ServFull = 1,
LLQErr_Static = 2,
LLQErr_FormErr = 3,
LLQErr_NoSuchLLQ = 4,
LLQErr_BadVers = 5,
LLQErr_UnknownErr = 6
};
enum { NoAnswer_Normal = 0, NoAnswer_Suspended = 1, NoAnswer_Fail = 2 };
#define HMAC_LEN 64
#define HMAC_IPAD 0x36
#define HMAC_OPAD 0x5c
#define MD5_LEN 16
#define AutoTunnelUnregistered(X) ( \
(X)->AutoTunnelHostRecord.resrec.RecordType == kDNSRecordTypeUnregistered && \
(X)->AutoTunnelDeviceInfo.resrec.RecordType == kDNSRecordTypeUnregistered && \
(X)->AutoTunnelService. resrec.RecordType == kDNSRecordTypeUnregistered )
// Internal data structure to maintain authentication information
typedef struct DomainAuthInfo
{
struct DomainAuthInfo *next;
mDNSs32 deltime; // If we're planning to delete this DomainAuthInfo, the time we want it deleted
mDNSBool AutoTunnel;
AuthRecord AutoTunnelHostRecord; // User-visible hostname; used as SRV target for AutoTunnel services
AuthRecord AutoTunnelTarget; // Opaque hostname of tunnel endpoint; used as SRV target for AutoTunnelService record
AuthRecord AutoTunnelDeviceInfo; // Device info of tunnel endpoint
AuthRecord AutoTunnelService; // Service record (possibly NAT-Mapped) of IKE daemon implementing tunnel endpoint
NATTraversalInfo AutoTunnelNAT;
domainname domain;
domainname keyname;
char b64keydata[32];
mDNSu8 keydata_ipad[HMAC_LEN]; // padded key for inner hash rounds
mDNSu8 keydata_opad[HMAC_LEN]; // padded key for outer hash rounds
} DomainAuthInfo;
// Note: Within an mDNSQuestionCallback mDNS all API calls are legal except mDNS_Init(), mDNS_Exit(), mDNS_Execute()
typedef enum { QC_rmv = 0, QC_add = 1, QC_addnocache = 2 } QC_result;
typedef void mDNSQuestionCallback(mDNS *const m, DNSQuestion *question, const ResourceRecord *const answer, QC_result AddRecord);
struct DNSQuestion_struct
{
// Internal state fields. These are used internally by mDNSCore; the client layer needn't be concerned with them.
DNSQuestion *next;
mDNSu32 qnamehash;
mDNSs32 DelayAnswering; // Set if we want to defer answering this question until the cache settles
mDNSs32 LastQTime; // Last scheduled transmission of this Q on *all* applicable interfaces
mDNSs32 ThisQInterval; // LastQTime + ThisQInterval is the next scheduled transmission of this Q
// ThisQInterval > 0 for an active question;
// ThisQInterval = 0 for a suspended question that's still in the list
// ThisQInterval = -1 for a cancelled question (should not still be in list)
mDNSs32 ExpectUnicastResp;// Set when we send a query with the kDNSQClass_UnicastResponse bit set
mDNSs32 LastAnswerPktNum; // The sequence number of the last response packet containing an answer to this Q
mDNSu32 RecentAnswerPkts; // Number of answers since the last time we sent this query
mDNSu32 CurrentAnswers; // Number of records currently in the cache that answer this question
mDNSu32 LargeAnswers; // Number of answers with rdata > 1024 bytes
mDNSu32 UniqueAnswers; // Number of answers received with kDNSClass_UniqueRRSet bit set
mDNSInterfaceID FlappingInterface1;// Set when an interface goes away, to flag if remove events are delivered for this Q
mDNSInterfaceID FlappingInterface2;// Set when an interface goes away, to flag if remove events are delivered for this Q
DomainAuthInfo *AuthInfo; // Non-NULL if query is currently being done using Private DNS
DNSQuestion *DuplicateOf;
DNSQuestion *NextInDQList;
DupSuppressInfo DupSuppress[DupSuppressInfoSize];
mDNSInterfaceID SendQNow; // The interface this query is being sent on right now
mDNSBool SendOnAll; // Set if we're sending this question on all active interfaces
mDNSu32 RequestUnicast; // Non-zero if we want to send query with kDNSQClass_UnicastResponse bit set
mDNSs32 LastQTxTime; // Last time this Q was sent on one (but not necessarily all) interfaces
mDNSu32 CNAMEReferrals; // Count of how many CNAME redirections we've done
// Wide Area fields. These are used internally by the uDNS core
UDPSocket *LocalSocket;
DNSServer *qDNSServer; // Caching server for this query (in the absence of an SRV saying otherwise)
mDNSu8 unansweredQueries;// The number of unanswered queries to this server
ZoneData *nta; // Used for getting zone data for private or LLQ query
mDNSAddr servAddr; // Address and port learned from _dns-llq, _dns-llq-tls or _dns-query-tls SRV query
mDNSIPPort servPort;
struct tcpInfo_t *tcp;
mDNSu8 NoAnswer; // Set if we want to suppress answers until tunnel setup has completed
// LLQ-specific fields. These fields are only meaningful when LongLived flag is set
LLQ_State state;
mDNSu32 ReqLease; // seconds (relative)
mDNSs32 expire; // ticks (absolute)
mDNSs16 ntries; // for UDP: the number of packets sent for this LLQ state
// for TCP: there is some ambiguity in the use of this variable, but in general, it is
// the number of TCP/TLS connection attempts for this LLQ state, or
// the number of packets sent for this TCP/TLS connection
mDNSOpaque64 id;
// Client API fields: The client must set up these fields *before* calling mDNS_StartQuery()
mDNSInterfaceID InterfaceID; // Non-zero if you want to issue queries only on a single specific IP interface
mDNSAddr Target; // Non-zero if you want to direct queries to a specific unicast target address
mDNSIPPort TargetPort; // Must be set if Target is set
mDNSOpaque16 TargetQID; // Must be set if Target is set
domainname qname;
mDNSu16 qtype;
mDNSu16 qclass;
mDNSBool LongLived; // Set by client for calls to mDNS_StartQuery to indicate LLQs to unicast layer.
mDNSBool ExpectUnique; // Set by client if it's expecting unique RR(s) for this question, not shared RRs
mDNSBool ForceMCast; // Set by client to force mDNS query, even for apparently uDNS names
mDNSBool ReturnIntermed; // Set by client to request callbacks for intermediate CNAME/NXDOMAIN results
mDNSQuestionCallback *QuestionCallback;
void *QuestionContext;
};
typedef struct
{
// Client API fields: The client must set up name and InterfaceID *before* calling mDNS_StartResolveService()
// When the callback is invoked, ip, port, TXTlen and TXTinfo will have been filled in with the results learned from the network.
domainname name;
mDNSInterfaceID InterfaceID; // ID of the interface the response was received on
mDNSAddr ip; // Remote (destination) IP address where this service can be accessed
mDNSIPPort port; // Port where this service can be accessed
mDNSu16 TXTlen;
mDNSu8 TXTinfo[2048]; // Additional demultiplexing information (e.g. LPR queue name)
} ServiceInfo;
// Note: Within an mDNSServiceInfoQueryCallback mDNS all API calls are legal except mDNS_Init(), mDNS_Exit(), mDNS_Execute()
typedef struct ServiceInfoQuery_struct ServiceInfoQuery;
typedef void mDNSServiceInfoQueryCallback(mDNS *const m, ServiceInfoQuery *query);
struct ServiceInfoQuery_struct
{
// Internal state fields. These are used internally by mDNSCore; the client layer needn't be concerned with them.
// No fields need to be set up by the client prior to calling mDNS_StartResolveService();
// all required data is passed as parameters to that function.
// The ServiceInfoQuery structure memory is working storage for mDNSCore to discover the requested information
// and place it in the ServiceInfo structure. After the client has called mDNS_StopResolveService(), it may
// dispose of the ServiceInfoQuery structure while retaining the results in the ServiceInfo structure.
DNSQuestion qSRV;
DNSQuestion qTXT;
DNSQuestion qAv4;
DNSQuestion qAv6;
mDNSu8 GotSRV;
mDNSu8 GotTXT;
mDNSu8 GotADD;
mDNSu32 Answers;
ServiceInfo *info;
mDNSServiceInfoQueryCallback *ServiceInfoQueryCallback;
void *ServiceInfoQueryContext;
};
typedef enum { ZoneServiceUpdate, ZoneServiceQuery, ZoneServiceLLQ } ZoneService;
typedef void ZoneDataCallback(mDNS *const m, mStatus err, const ZoneData *result);
struct ZoneData_struct
{
domainname ChildName; // Name for which we're trying to find the responsible server
ZoneService ZoneService; // Which service we're seeking for this zone (update, query, or LLQ)
domainname *CurrentSOA; // Points to somewhere within ChildName
domainname ZoneName; // Discovered result: Left-hand-side of SOA record
mDNSu16 ZoneClass; // Discovered result: DNS Class from SOA record
domainname Host; // Discovered result: Target host from SRV record
mDNSIPPort Port; // Discovered result: Update port, query port, or LLQ port from SRV record
mDNSAddr Addr; // Discovered result: Address of Target host from SRV record
mDNSBool ZonePrivate; // Discovered result: Does zone require encrypted queries?
ZoneDataCallback *ZoneDataCallback; // Caller-specified function to be called upon completion
void *ZoneDataContext;
DNSQuestion question; // Storage for any active question
};
extern ZoneData *StartGetZoneData(mDNS *const m, const domainname *const name, const ZoneService target, ZoneDataCallback callback, void *callbackInfo);
extern void CancelGetZoneData(mDNS *const m, ZoneData *nta);
typedef struct DNameListElem
{
struct DNameListElem *next;
mDNSu32 uid;
domainname name;
} DNameListElem;
#if APPLE_OSX_mDNSResponder
typedef struct ClientTunnel
{
struct ClientTunnel *next;
domainname dstname;
mDNSBool MarkedForDeletion;
mDNSv6Addr loc_inner;
mDNSv4Addr loc_outer;
mDNSv6Addr rmt_inner;
mDNSv4Addr rmt_outer;
mDNSIPPort rmt_outer_port;
DNSQuestion q;
} ClientTunnel;
#endif
// ***************************************************************************
#if 0
#pragma mark -
#pragma mark - NetworkInterfaceInfo_struct
#endif
typedef struct NetworkInterfaceInfo_struct NetworkInterfaceInfo;
// A NetworkInterfaceInfo_struct serves two purposes:
// 1. It holds the address, PTR and HINFO records to advertise a given IP address on a given physical interface
// 2. It tells mDNSCore which physical interfaces are available; each physical interface has its own unique InterfaceID.
// Since there may be multiple IP addresses on a single physical interface,
// there may be multiple NetworkInterfaceInfo_structs with the same InterfaceID.
// In this case, to avoid sending the same packet n times, when there's more than one
// struct with the same InterfaceID, mDNSCore picks one member of the set to be the
// active representative of the set; all others have the 'InterfaceActive' flag unset.
struct NetworkInterfaceInfo_struct
{
// Internal state fields. These are used internally by mDNSCore; the client layer needn't be concerned with them.
NetworkInterfaceInfo *next;
mDNSu8 InterfaceActive; // Set if interface is sending & receiving packets (see comment above)
mDNSu8 IPv4Available; // If InterfaceActive, set if v4 available on this InterfaceID
mDNSu8 IPv6Available; // If InterfaceActive, set if v6 available on this InterfaceID
DNSQuestion NetWakeBrowse;
DNSQuestion NetWakeResolve[3]; // For fault-tolerance, we try up to three Sleep Proxies
mDNSAddr SPSAddr[3];
mDNSIPPort SPSPort[3];
mDNSs32 NextSPSAttempt; // -1 if we're not currently attempting to register with any Sleep Proxy
mDNSs32 NextSPSAttemptTime;
// Standard AuthRecords that every Responder host should have (one per active IP address)
AuthRecord RR_A; // 'A' or 'AAAA' (address) record for our ".local" name
AuthRecord RR_PTR; // PTR (reverse lookup) record
AuthRecord RR_HINFO;
// Client API fields: The client must set up these fields *before* calling mDNS_RegisterInterface()
mDNSInterfaceID InterfaceID; // Identifies physical interface; MUST NOT be 0, -1, or -2
mDNSAddr ip; // The IPv4 or IPv6 address to advertise
mDNSAddr mask;
mDNSEthAddr MAC;
char ifname[64]; // Windows uses a GUID string for the interface name, which doesn't fit in 16 bytes
mDNSu8 Advertise; // False if you are only searching on this interface
mDNSu8 McastTxRx; // Send/Receive multicast on this { InterfaceID, address family } ?
mDNSu8 NetWake; // Set if Wake-On-Magic-Packet is enabled on this interface
};
typedef struct SearchListElem
{
struct SearchListElem *next;
domainname domain;
int flag; // -1 means delete, 0 means unchanged, +1 means newly added
DNSQuestion BrowseQ;
DNSQuestion DefBrowseQ;
DNSQuestion AutomaticBrowseQ;
DNSQuestion RegisterQ;
DNSQuestion DefRegisterQ;
ARListElem *AuthRecs;
} SearchListElem;
// For domain enumeration and automatic browsing
// This is the user's DNS search list.
// In each of these domains we search for our special pointer records (lb._dns-sd._udp.<domain>, etc.)
// to discover recommended domains for domain enumeration (browse, default browse, registration,
// default registration) and possibly one or more recommended automatic browsing domains.
extern SearchListElem *SearchList; // This really ought to be part of mDNS_struct -- SC
// ***************************************************************************
#if 0
#pragma mark -
#pragma mark - Main mDNS object, used to hold all the mDNS state
#endif
typedef void mDNSCallback(mDNS *const m, mStatus result);
#define CACHE_HASH_SLOTS 499
enum
{
mDNS_KnownBug_PhantomInterfaces = 1,
mDNS_KnownBug_LossySyslog = 2 // <rdar://problem/6561888>
};
enum
{
SleepState_Awake = 0,
SleepState_Transferring = 1,
SleepState_Sleeping = 2
};
struct mDNS_struct
{
// Internal state fields. These hold the main internal state of mDNSCore;
// the client layer needn't be concerned with them.
// No fields need to be set up by the client prior to calling mDNS_Init();
// all required data is passed as parameters to that function.
mDNS_PlatformSupport *p; // Pointer to platform-specific data of indeterminite size
mDNSu32 KnownBugs;
mDNSBool CanReceiveUnicastOn5353;
mDNSBool AdvertiseLocalAddresses;
mDNSBool DivertMulticastAdvertisements; // from interfaces that do not advertise local addresses to local-only
mStatus mDNSPlatformStatus;
mDNSIPPort UnicastPort4;
mDNSIPPort UnicastPort6;
mDNSEthAddr PrimaryMAC; // Used as unique host ID
mDNSCallback *MainCallback;
void *MainContext;
// For debugging: To catch and report locking failures
mDNSu32 mDNS_busy; // Incremented between mDNS_Lock/mDNS_Unlock section
mDNSu32 mDNS_reentrancy; // Incremented when calling a client callback
mDNSu8 lock_rrcache; // For debugging: Set at times when these lists may not be modified
mDNSu8 lock_Questions;
mDNSu8 lock_Records;
#ifndef MaxMsg
#define MaxMsg 160
#endif
char MsgBuffer[MaxMsg]; // Temp storage used while building error log messages
// Task Scheduling variables
mDNSs32 timenow_adjust; // Correction applied if we ever discover time went backwards
mDNSs32 timenow; // The time that this particular activation of the mDNS code started
mDNSs32 timenow_last; // The time the last time we ran
mDNSs32 NextScheduledEvent; // Derived from values below
mDNSs32 ShutdownTime; // Set when we're shutting down; allows us to skip some unnecessary steps
mDNSs32 SuppressSending; // Don't send *any* packets during this time
mDNSs32 NextCacheCheck; // Next time to refresh cache record before it expires
mDNSs32 NextScheduledQuery; // Next time to send query in its exponential backoff sequence
mDNSs32 NextScheduledProbe; // Next time to probe for new authoritative record
mDNSs32 NextScheduledResponse; // Next time to send authoritative record(s) in responses
mDNSs32 NextScheduledNATOp; // Next time to send NAT-traversal packets
mDNSs32 NextScheduledSPS; // Next time to purge expiring Sleep Proxy records
mDNSs32 RandomQueryDelay; // For de-synchronization of query packets on the wire
mDNSu32 RandomReconfirmDelay; // For de-synchronization of reconfirmation queries on the wire
mDNSs32 PktNum; // Unique sequence number assigned to each received packet
mDNSu8 SleepState; // Set if we're sleeping
mDNSu8 SleepSeqNum; // "Epoch number" of our current period of wakefulness
mDNSu8 SystemWakeOnLANEnabled; // Set if we want to register with a Sleep Proxy before going to sleep
mDNSu8 SentSleepProxyRegistration;// Set if we registered (or tried to register) with a Sleep Proxy
mDNSs32 AnnounceOwner; // After waking from sleep, include OWNER option in packets until this time
mDNSs32 DelaySleep; // To inhibit re-sleeping too quickly right after wake
mDNSs32 SleepLimit; // Time window to allow deregistrations, etc.,
// during which underying platform layer should inhibit system sleep
mDNSs32 NextScheduledSPRetry; // Time next sleep proxy registration action is required.
// Only valid if SleepLimit is nonzero and DelaySleep is zero.
// These fields only required for mDNS Searcher...
DNSQuestion *Questions; // List of all registered questions, active and inactive
DNSQuestion *NewQuestions; // Fresh questions not yet answered from cache
DNSQuestion *CurrentQuestion; // Next question about to be examined in AnswerLocalQuestions()
DNSQuestion *LocalOnlyQuestions; // Questions with InterfaceID set to mDNSInterface_LocalOnly
DNSQuestion *NewLocalOnlyQuestions; // Fresh local-only questions not yet answered
mDNSu32 rrcache_size; // Total number of available cache entries
mDNSu32 rrcache_totalused; // Number of cache entries currently occupied
mDNSu32 rrcache_active; // Number of cache entries currently occupied by records that answer active questions
mDNSu32 rrcache_report;
CacheEntity *rrcache_free;
CacheGroup *rrcache_hash[CACHE_HASH_SLOTS];
// Fields below only required for mDNS Responder...
domainlabel nicelabel; // Rich text label encoded using canonically precomposed UTF-8
domainlabel hostlabel; // Conforms to RFC 1034 "letter-digit-hyphen" ARPANET host name rules
domainname MulticastHostname; // Fully Qualified "dot-local" Host Name, e.g. "Foo.local."
UTF8str255 HIHardware;
UTF8str255 HISoftware;
AuthRecord DeviceInfo;
AuthRecord *ResourceRecords;
AuthRecord *DuplicateRecords; // Records currently 'on hold' because they are duplicates of existing records
AuthRecord *NewLocalRecords; // Fresh local-only records not yet delivered to local-only questions
AuthRecord *CurrentRecord; // Next AuthRecord about to be examined
NetworkInterfaceInfo *HostInterfaces;
mDNSs32 ProbeFailTime;
mDNSu32 NumFailedProbes;
mDNSs32 SuppressProbes;
// Unicast-specific data
mDNSs32 NextuDNSEvent; // uDNS next event
mDNSs32 NextSRVUpdate; // Time to perform delayed update
mDNSs32 SuppressStdPort53Queries; // Wait before allowing the next standard unicast query to the user's configured DNS server
ServiceRecordSet *ServiceRegistrations;
DNSServer *DNSServers; // list of DNS servers
mDNSAddr Router;
mDNSAddr AdvertisedV4; // IPv4 address pointed to by hostname
mDNSAddr AdvertisedV6; // IPv6 address pointed to by hostname
DomainAuthInfo *AuthInfoList; // list of domains requiring authentication for updates
DNSQuestion ReverseMap; // Reverse-map query to find static hostname for service target
DNSQuestion AutomaticBrowseDomainQ;
domainname StaticHostname; // Current answer to reverse-map query
domainname FQDN;
HostnameInfo *Hostnames; // List of registered hostnames + hostname metadata
mDNSv6Addr AutoTunnelHostAddr; // IPv6 address advertised for AutoTunnel services on this machine
mDNSBool AutoTunnelHostAddrActive;
domainlabel AutoTunnelLabel; // Used to construct hostname for *IPv4* address of tunnel endpoints
mDNSBool RegisterSearchDomains;
// NAT-Traversal fields
NATTraversalInfo LLQNAT; // Single shared NAT Traversal to receive inbound LLQ notifications
NATTraversalInfo *NATTraversals;
NATTraversalInfo *CurrentNATTraversal;
mDNSs32 retryIntervalGetAddr; // delta between time sent and retry
mDNSs32 retryGetAddr; // absolute time when we retry
mDNSv4Addr ExternalAddress;
UDPSocket *NATMcastRecvskt; // For receiving NAT-PMP AddrReply multicasts from router on port 5350
mDNSu32 LastNATupseconds; // NAT engine uptime in seconds, from most recent NAT packet
mDNSs32 LastNATReplyLocalTime; // Local time in ticks when most recent NAT packet was received
mDNSu16 LastNATMapResultCode; // Most recent error code for mappings
tcpLNTInfo tcpAddrInfo; // legacy NAT traversal TCP connection info for external address
tcpLNTInfo tcpDeviceInfo; // legacy NAT traversal TCP connection info for device info
tcpLNTInfo *tcpInfoUnmapList; // list of pending unmap requests
mDNSInterfaceID UPnPInterfaceID;
UDPSocket *SSDPSocket; // For SSDP request/response
mDNSBool SSDPWANPPPConnection; // whether we should send the SSDP query for WANIPConnection or WANPPPConnection
mDNSIPPort UPnPRouterPort; // port we send discovery messages to
mDNSIPPort UPnPSOAPPort; // port we send SOAP messages to
mDNSu8 *UPnPRouterURL; // router's URL string
mDNSBool UPnPWANPPPConnection; // whether we're using WANIPConnection or WANPPPConnection
mDNSu8 *UPnPSOAPURL; // router's SOAP control URL string
mDNSu8 *UPnPRouterAddressString; // holds both the router's address and port
mDNSu8 *UPnPSOAPAddressString; // holds both address and port for SOAP messages
// Sleep Proxy Server fields
mDNSu8 SPSType; // 0 = off, 10-99 encodes desirability metric
mDNSu8 SPSPortability; // 10-99
mDNSu8 SPSMarginalPower; // 10-99
mDNSu8 SPSTotalPower; // 10-99
mDNSu8 SPSState; // 0 = off, 1 = running, 2 = shutting down, 3 = suspended during sleep
mDNSInterfaceID SPSProxyListChanged;
UDPSocket *SPSSocket;
ServiceRecordSet SPSRecords;
mDNSQuestionCallback *SPSBrowseCallback; // So the platform layer can do something useful with SPS browse results
int ProxyRecords; // Total number of records we're holding as proxy
#define MAX_PROXY_RECORDS 10000 /* DOS protection: 400 machines at 25 records each */
#if APPLE_OSX_mDNSResponder
ClientTunnel *TunnelClients;
uuid_t asl_uuid; // uuid for ASL logging
#endif
// Fixed storage, to avoid creating large objects on the stack
// The imsg is declared as a union with a pointer type to enforce CPU-appropriate alignment
union { DNSMessage m; void *p; } imsg; // Incoming message received from wire
DNSMessage omsg; // Outgoing message we're building
LargeCacheRecord rec; // Resource Record extracted from received message
};
#define FORALL_CACHERECORDS(SLOT,CG,CR) \
for ((SLOT) = 0; (SLOT) < CACHE_HASH_SLOTS; (SLOT)++) \
for ((CG)=m->rrcache_hash[(SLOT)]; (CG); (CG)=(CG)->next) \
for ((CR) = (CG)->members; (CR); (CR)=(CR)->next)
// ***************************************************************************
#if 0
#pragma mark -
#pragma mark - Useful Static Constants
#endif
extern const mDNSIPPort zeroIPPort;
extern const mDNSv4Addr zerov4Addr;
extern const mDNSv6Addr zerov6Addr;
extern const mDNSEthAddr zeroEthAddr;
extern const mDNSv4Addr onesIPv4Addr;
extern const mDNSv6Addr onesIPv6Addr;
extern const mDNSEthAddr onesEthAddr;
extern const mDNSAddr zeroAddr;
extern const OwnerOptData zeroOwner;
extern const mDNSInterfaceID mDNSInterface_Any; // Zero
extern const mDNSInterfaceID mDNSInterface_LocalOnly; // Special value
extern const mDNSInterfaceID mDNSInterface_Unicast; // Special value
extern const mDNSInterfaceID mDNSInterfaceMark; // Special value
extern const mDNSIPPort DiscardPort;
extern const mDNSIPPort SSHPort;
extern const mDNSIPPort UnicastDNSPort;
extern const mDNSIPPort SSDPPort;
extern const mDNSIPPort IPSECPort;
extern const mDNSIPPort NSIPCPort;
extern const mDNSIPPort NATPMPAnnouncementPort;
extern const mDNSIPPort NATPMPPort;
extern const mDNSIPPort DNSEXTPort;
extern const mDNSIPPort MulticastDNSPort;
extern const mDNSIPPort LoopbackIPCPort;
extern const mDNSIPPort PrivateDNSPort;
extern const mDNSv4Addr AllDNSAdminGroup;
extern const mDNSv4Addr AllSystemsMcast;
extern const mDNSAddr AllDNSLinkGroup_v4;
extern const mDNSAddr AllDNSLinkGroup_v6;
extern const mDNSOpaque16 zeroID;
extern const mDNSOpaque16 onesID;
extern const mDNSOpaque16 QueryFlags;
extern const mDNSOpaque16 uQueryFlags;
extern const mDNSOpaque16 ResponseFlags;
extern const mDNSOpaque16 UpdateReqFlags;
extern const mDNSOpaque16 UpdateRespFlags;
extern const mDNSOpaque64 zeroOpaque64;
extern mDNSBool StrictUnicastOrdering;
#define localdomain (*(const domainname *)"\x5" "local")
#define DeviceInfoName (*(const domainname *)"\xC" "_device-info" "\x4" "_tcp")
#define SleepProxyServiceType (*(const domainname *)"\xC" "_sleep-proxy" "\x4" "_udp")
// ***************************************************************************
#if 0
#pragma mark -
#pragma mark - Inline functions
#endif
#if (defined(_MSC_VER))
#define mDNSinline static __inline
#elif ((__GNUC__ > 2) || ((__GNUC__ == 2) && (__GNUC_MINOR__ >= 9)))
#define mDNSinline static inline
#endif
// If we're not doing inline functions, then this header needs to have the extern declarations
#if !defined(mDNSinline)
extern mDNSs32 NonZeroTime(mDNSs32 t);
extern mDNSu16 mDNSVal16(mDNSOpaque16 x);
extern mDNSOpaque16 mDNSOpaque16fromIntVal(mDNSu16 v);
#endif
// If we're compiling the particular C file that instantiates our inlines, then we
// define "mDNSinline" (to empty string) so that we generate code in the following section
#if (!defined(mDNSinline) && mDNS_InstantiateInlines)
#define mDNSinline
#endif
#ifdef mDNSinline
mDNSinline mDNSs32 NonZeroTime(mDNSs32 t) { if (t) return(t); else return(1); }
mDNSinline mDNSu16 mDNSVal16(mDNSOpaque16 x) { return((mDNSu16)((mDNSu16)x.b[0] << 8 | (mDNSu16)x.b[1])); }
mDNSinline mDNSOpaque16 mDNSOpaque16fromIntVal(mDNSu16 v)
{
mDNSOpaque16 x;
x.b[0] = (mDNSu8)(v >> 8);
x.b[1] = (mDNSu8)(v & 0xFF);
return(x);
}
#endif
// ***************************************************************************
#if 0
#pragma mark -
#pragma mark - Main Client Functions
#endif
// Every client should call mDNS_Init, passing in storage for the mDNS object and the mDNS_PlatformSupport object.
//
// Clients that are only advertising services should use mDNS_Init_NoCache and mDNS_Init_ZeroCacheSize.
// Clients that plan to perform queries (mDNS_StartQuery, mDNS_StartBrowse, mDNS_StartResolveService, etc.)
// need to provide storage for the resource record cache, or the query calls will return 'mStatus_NoCache'.
// The rrcachestorage parameter is the address of memory for the resource record cache, and
// the rrcachesize parameter is the number of entries in the CacheRecord array passed in.
// (i.e. the size of the cache memory needs to be sizeof(CacheRecord) * rrcachesize).
// OS X 10.3 Panther uses an initial cache size of 64 entries, and then mDNSCore sends an
// mStatus_GrowCache message if it needs more.
//
// Most clients should use mDNS_Init_AdvertiseLocalAddresses. This causes mDNSCore to automatically
// create the correct address records for all the hosts interfaces. If you plan to advertise
// services being offered by the local machine, this is almost always what you want.
// There are two cases where you might use mDNS_Init_DontAdvertiseLocalAddresses:
// 1. A client-only device, that browses for services but doesn't advertise any of its own.
// 2. A proxy-registration service, that advertises services being offered by other machines, and takes
// the appropriate steps to manually create the correct address records for those other machines.
// In principle, a proxy-like registration service could manually create address records for its own machine too,
// but this would be pointless extra effort when using mDNS_Init_AdvertiseLocalAddresses does that for you.
//
// Note that a client-only device that wishes to prohibit multicast advertisements (e.g. from
// higher-layer API calls) must also set DivertMulticastAdvertisements in the mDNS structure and
// advertise local address(es) on a loopback interface.
//
// When mDNS has finished setting up the client's callback is called
// A client can also spin and poll the mDNSPlatformStatus field to see when it changes from mStatus_Waiting to mStatus_NoError
//
// Call mDNS_StartExit to tidy up before exiting
// Because exiting may be an asynchronous process (e.g. if unicast records need to be deregistered)
// client layer may choose to wait until mDNS_ExitNow() returns true before calling mDNS_FinalExit().
//
// Call mDNS_Register with a completed AuthRecord object to register a resource record
// If the resource record type is kDNSRecordTypeUnique (or kDNSknownunique) then if a conflicting resource record is discovered,
// the resource record's mDNSRecordCallback will be called with error code mStatus_NameConflict. The callback should deregister
// the record, and may then try registering the record again after picking a new name (e.g. by automatically appending a number).
// Following deregistration, the RecordCallback will be called with result mStatus_MemFree to signal that it is safe to deallocate
// the record's storage (memory must be freed asynchronously to allow for goodbye packets and dynamic update deregistration).
//
// Call mDNS_StartQuery to initiate a query. mDNS will proceed to issue Multicast DNS query packets, and any time a response
// is received containing a record which matches the question, the DNSQuestion's mDNSAnswerCallback function will be called
// Call mDNS_StopQuery when no more answers are required
//
// Care should be taken on multi-threaded or interrupt-driven environments.
// The main mDNS routines call mDNSPlatformLock() on entry and mDNSPlatformUnlock() on exit;
// each platform layer needs to implement these appropriately for its respective platform.
// For example, if the support code on a particular platform implements timer callbacks at interrupt time, then
// mDNSPlatformLock/Unlock need to disable interrupts or do similar concurrency control to ensure that the mDNS
// code is not entered by an interrupt-time timer callback while in the middle of processing a client call.
extern mStatus mDNS_Init (mDNS *const m, mDNS_PlatformSupport *const p,
CacheEntity *rrcachestorage, mDNSu32 rrcachesize,
mDNSBool AdvertiseLocalAddresses,
mDNSCallback *Callback, void *Context);
// See notes above on use of NoCache/ZeroCacheSize
#define mDNS_Init_NoCache mDNSNULL
#define mDNS_Init_ZeroCacheSize 0
// See notes above on use of Advertise/DontAdvertiseLocalAddresses
#define mDNS_Init_AdvertiseLocalAddresses mDNStrue
#define mDNS_Init_DontAdvertiseLocalAddresses mDNSfalse
#define mDNS_Init_NoInitCallback mDNSNULL
#define mDNS_Init_NoInitCallbackContext mDNSNULL
extern void mDNS_ConfigChanged(mDNS *const m);
extern void mDNS_GrowCache (mDNS *const m, CacheEntity *storage, mDNSu32 numrecords);
extern void mDNS_StartExit (mDNS *const m);
extern void mDNS_FinalExit (mDNS *const m);
#define mDNS_Close(m) do { mDNS_StartExit(m); mDNS_FinalExit(m); } while(0)
#define mDNS_ExitNow(m, now) ((now) - (m)->ShutdownTime >= 0 || (!(m)->ResourceRecords && !(m)->ServiceRegistrations))
extern mDNSs32 mDNS_Execute (mDNS *const m);
extern mStatus mDNS_Register (mDNS *const m, AuthRecord *const rr);
extern mStatus mDNS_Update (mDNS *const m, AuthRecord *const rr, mDNSu32 newttl,
const mDNSu16 newrdlength, RData *const newrdata, mDNSRecordUpdateCallback *Callback);
extern mStatus mDNS_Deregister(mDNS *const m, AuthRecord *const rr);
extern mStatus mDNS_StartQuery(mDNS *const m, DNSQuestion *const question);
extern mStatus mDNS_StopQuery (mDNS *const m, DNSQuestion *const question);
extern mStatus mDNS_StopQueryWithRemoves(mDNS *const m, DNSQuestion *const question);
extern mStatus mDNS_Reconfirm (mDNS *const m, CacheRecord *const cacherr);
extern mStatus mDNS_ReconfirmByValue(mDNS *const m, ResourceRecord *const rr);
extern void mDNS_PurgeCacheResourceRecord(mDNS *const m, CacheRecord *rr);
extern mDNSs32 mDNS_TimeNow(const mDNS *const m);
extern mStatus mDNS_StartNATOperation(mDNS *const m, NATTraversalInfo *traversal);
extern mStatus mDNS_StopNATOperation(mDNS *const m, NATTraversalInfo *traversal);
extern mStatus mDNS_StopNATOperation_internal(mDNS *m, NATTraversalInfo *traversal);
extern DomainAuthInfo *GetAuthInfoForName(mDNS *m, const domainname *const name);
// ***************************************************************************
#if 0
#pragma mark -
#pragma mark - Platform support functions that are accessible to the client layer too
#endif
extern mDNSs32 mDNSPlatformOneSecond;
// ***************************************************************************
#if 0
#pragma mark -
#pragma mark - General utility and helper functions
#endif
// mDNS_RegisterService is a single call to register the set of resource records associated with a given named service.
//
// mDNS_StartResolveService is single call which is equivalent to multiple calls to mDNS_StartQuery,
// to find the IP address, port number, and demultiplexing information for a given named service.
// As with mDNS_StartQuery, it executes asynchronously, and calls the ServiceInfoQueryCallback when the answer is
// found. After the service is resolved, the client should call mDNS_StopResolveService to complete the transaction.
// The client can also call mDNS_StopResolveService at any time to abort the transaction.
//
// mDNS_AddRecordToService adds an additional record to a Service Record Set. This record may be deregistered
// via mDNS_RemoveRecordFromService, or by deregistering the service. mDNS_RemoveRecordFromService is passed a
// callback to free the memory associated with the extra RR when it is safe to do so. The ExtraResourceRecord
// object can be found in the record's context pointer.
// mDNS_GetBrowseDomains is a special case of the mDNS_StartQuery call, where the resulting answers
// are a list of PTR records indicating (in the rdata) domains that are recommended for browsing.
// After getting the list of domains to browse, call mDNS_StopQuery to end the search.
// mDNS_GetDefaultBrowseDomain returns the name of the domain that should be highlighted by default.
//
// mDNS_GetRegistrationDomains and mDNS_GetDefaultRegistrationDomain are the equivalent calls to get the list
// of one or more domains that should be offered to the user as choices for where they may register their service,
// and the default domain in which to register in the case where the user has made no selection.
extern void mDNS_SetupResourceRecord(AuthRecord *rr, RData *RDataStorage, mDNSInterfaceID InterfaceID,
mDNSu16 rrtype, mDNSu32 ttl, mDNSu8 RecordType, mDNSRecordCallback Callback, void *Context);
extern mStatus mDNS_RegisterService (mDNS *const m, ServiceRecordSet *sr,
const domainlabel *const name, const domainname *const type, const domainname *const domain,
const domainname *const host, mDNSIPPort port, const mDNSu8 txtinfo[], mDNSu16 txtlen,
AuthRecord *SubTypes, mDNSu32 NumSubTypes,
const mDNSInterfaceID InterfaceID, mDNSServiceCallback Callback, void *Context);
extern mStatus mDNS_AddRecordToService(mDNS *const m, ServiceRecordSet *sr, ExtraResourceRecord *extra, RData *rdata, mDNSu32 ttl);
extern mStatus mDNS_RemoveRecordFromService(mDNS *const m, ServiceRecordSet *sr, ExtraResourceRecord *extra, mDNSRecordCallback MemFreeCallback, void *Context);
extern mStatus mDNS_RenameAndReregisterService(mDNS *const m, ServiceRecordSet *const sr, const domainlabel *newname);
extern mStatus mDNS_DeregisterService(mDNS *const m, ServiceRecordSet *sr);
extern mStatus mDNS_RegisterNoSuchService(mDNS *const m, AuthRecord *const rr,
const domainlabel *const name, const domainname *const type, const domainname *const domain,
const domainname *const host,
const mDNSInterfaceID InterfaceID, mDNSRecordCallback Callback, void *Context);
#define mDNS_DeregisterNoSuchService mDNS_Deregister
extern void mDNS_SetupQuestion(DNSQuestion *const q, const mDNSInterfaceID InterfaceID, const domainname *const name,
const mDNSu16 qtype, mDNSQuestionCallback *const callback, void *const context);
extern mStatus mDNS_StartBrowse(mDNS *const m, DNSQuestion *const question,
const domainname *const srv, const domainname *const domain,
const mDNSInterfaceID InterfaceID, mDNSBool ForceMCast, mDNSQuestionCallback *Callback, void *Context);
#define mDNS_StopBrowse mDNS_StopQuery
extern mStatus mDNS_StartResolveService(mDNS *const m, ServiceInfoQuery *query, ServiceInfo *info, mDNSServiceInfoQueryCallback *Callback, void *Context);
extern void mDNS_StopResolveService (mDNS *const m, ServiceInfoQuery *query);
typedef enum
{
mDNS_DomainTypeBrowse = 0,
mDNS_DomainTypeBrowseDefault = 1,
mDNS_DomainTypeBrowseAutomatic = 2,
mDNS_DomainTypeRegistration = 3,
mDNS_DomainTypeRegistrationDefault = 4,
mDNS_DomainTypeMax = 4
} mDNS_DomainType;
extern const char *const mDNS_DomainTypeNames[];
extern mStatus mDNS_GetDomains(mDNS *const m, DNSQuestion *const question, mDNS_DomainType DomainType, const domainname *dom,
const mDNSInterfaceID InterfaceID, mDNSQuestionCallback *Callback, void *Context);
#define mDNS_StopGetDomains mDNS_StopQuery
extern mStatus mDNS_AdvertiseDomains(mDNS *const m, AuthRecord *rr, mDNS_DomainType DomainType, const mDNSInterfaceID InterfaceID, char *domname);
#define mDNS_StopAdvertiseDomains mDNS_Deregister
extern mDNSOpaque16 mDNS_NewMessageID(mDNS *const m);
extern DNSServer *GetServerForName(mDNS *m, const domainname *name, DNSServer *current);
// ***************************************************************************
#if 0
#pragma mark -
#pragma mark - DNS name utility functions
#endif
// In order to expose the full capabilities of the DNS protocol (which allows any arbitrary eight-bit values
// in domain name labels, including unlikely characters like ascii nulls and even dots) all the mDNS APIs
// work with DNS's native length-prefixed strings. For convenience in C, the following utility functions
// are provided for converting between C's null-terminated strings and DNS's length-prefixed strings.
// Assignment
// A simple C structure assignment of a domainname can cause a protection fault by accessing unmapped memory,
// because that object is defined to be 256 bytes long, but not all domainname objects are truly the full size.
// This macro uses mDNSPlatformMemCopy() to make sure it only touches the actual bytes that are valid.
#define AssignDomainName(DST, SRC) do { mDNSu16 len__ = DomainNameLength((SRC)); \
if (len__ <= MAX_DOMAIN_NAME) mDNSPlatformMemCopy((DST)->c, (SRC)->c, len__); else (DST)->c[0] = 0; } while(0)
// Comparison functions
#define SameDomainLabelCS(A,B) ((A)[0] == (B)[0] && mDNSPlatformMemSame((A)+1, (B)+1, (A)[0]))
extern mDNSBool SameDomainLabel(const mDNSu8 *a, const mDNSu8 *b);
extern mDNSBool SameDomainName(const domainname *const d1, const domainname *const d2);
extern mDNSBool SameDomainNameCS(const domainname *const d1, const domainname *const d2);
extern mDNSBool IsLocalDomain(const domainname *d); // returns true for domains that by default should be looked up using link-local multicast
#define StripFirstLabel(X) ((const domainname *)&(X)->c[(X)->c[0] ? 1 + (X)->c[0] : 0])
#define FirstLabel(X) ((const domainlabel *)(X))
#define SecondLabel(X) ((const domainlabel *)StripFirstLabel(X))
#define ThirdLabel(X) ((const domainlabel *)StripFirstLabel(StripFirstLabel(X)))
extern const mDNSu8 *LastLabel(const domainname *d);
// Get total length of domain name, in native DNS format, including terminal root label
// (e.g. length of "com." is 5 (length byte, three data bytes, final zero)
extern mDNSu16 DomainNameLengthLimit(const domainname *const name, const mDNSu8 *limit);
#define DomainNameLength(name) DomainNameLengthLimit((name), (name)->c + MAX_DOMAIN_NAME)
// Append functions to append one or more labels to an existing native format domain name:
// AppendLiteralLabelString adds a single label from a literal C string, with no escape character interpretation.
// AppendDNSNameString adds zero or more labels from a C string using conventional DNS dots-and-escaping interpretation
// AppendDomainLabel adds a single label from a native format domainlabel
// AppendDomainName adds zero or more labels from a native format domainname
extern mDNSu8 *AppendLiteralLabelString(domainname *const name, const char *cstr);
extern mDNSu8 *AppendDNSNameString (domainname *const name, const char *cstr);
extern mDNSu8 *AppendDomainLabel (domainname *const name, const domainlabel *const label);
extern mDNSu8 *AppendDomainName (domainname *const name, const domainname *const append);
// Convert from null-terminated string to native DNS format:
// The DomainLabel form makes a single label from a literal C string, with no escape character interpretation.
// The DomainName form makes native format domain name from a C string using conventional DNS interpretation:
// dots separate labels, and within each label, '\.' represents a literal dot, '\\' represents a literal
// backslash and backslash with three decimal digits (e.g. \000) represents an arbitrary byte value.
extern mDNSBool MakeDomainLabelFromLiteralString(domainlabel *const label, const char *cstr);
extern mDNSu8 *MakeDomainNameFromDNSNameString (domainname *const name, const char *cstr);
// Convert native format domainlabel or domainname back to C string format
// IMPORTANT:
// When using ConvertDomainLabelToCString, the target buffer must be MAX_ESCAPED_DOMAIN_LABEL (254) bytes long
// to guarantee there will be no buffer overrun. It is only safe to use a buffer shorter than this in rare cases
// where the label is known to be constrained somehow (for example, if the label is known to be either "_tcp" or "_udp").
// Similarly, when using ConvertDomainNameToCString, the target buffer must be MAX_ESCAPED_DOMAIN_NAME (1009) bytes long.
// See definitions of MAX_ESCAPED_DOMAIN_LABEL and MAX_ESCAPED_DOMAIN_NAME for more detailed explanation.
extern char *ConvertDomainLabelToCString_withescape(const domainlabel *const name, char *cstr, char esc);
#define ConvertDomainLabelToCString_unescaped(D,C) ConvertDomainLabelToCString_withescape((D), (C), 0)
#define ConvertDomainLabelToCString(D,C) ConvertDomainLabelToCString_withescape((D), (C), '\\')
extern char *ConvertDomainNameToCString_withescape(const domainname *const name, char *cstr, char esc);
#define ConvertDomainNameToCString_unescaped(D,C) ConvertDomainNameToCString_withescape((D), (C), 0)
#define ConvertDomainNameToCString(D,C) ConvertDomainNameToCString_withescape((D), (C), '\\')
extern void ConvertUTF8PstringToRFC1034HostLabel(const mDNSu8 UTF8Name[], domainlabel *const hostlabel);
extern mDNSu8 *ConstructServiceName(domainname *const fqdn, const domainlabel *name, const domainname *type, const domainname *const domain);
extern mDNSBool DeconstructServiceName(const domainname *const fqdn, domainlabel *const name, domainname *const type, domainname *const domain);
// Note: Some old functions have been replaced by more sensibly-named versions.
// You can uncomment the hash-defines below if you don't want to have to change your source code right away.
// When updating your code, note that (unlike the old versions) *all* the new routines take the target object
// as their first parameter.
//#define ConvertCStringToDomainName(SRC,DST) MakeDomainNameFromDNSNameString((DST),(SRC))
//#define ConvertCStringToDomainLabel(SRC,DST) MakeDomainLabelFromLiteralString((DST),(SRC))
//#define AppendStringLabelToName(DST,SRC) AppendLiteralLabelString((DST),(SRC))
//#define AppendStringNameToName(DST,SRC) AppendDNSNameString((DST),(SRC))
//#define AppendDomainLabelToName(DST,SRC) AppendDomainLabel((DST),(SRC))
//#define AppendDomainNameToName(DST,SRC) AppendDomainName((DST),(SRC))
// ***************************************************************************
#if 0
#pragma mark -
#pragma mark - Other utility functions and macros
#endif
// mDNS_vsnprintf/snprintf return the number of characters written, excluding the final terminating null.
// The output is always null-terminated: for example, if the output turns out to be exactly buflen long,
// then the output will be truncated by one character to allow space for the terminating null.
// Unlike standard C vsnprintf/snprintf, they return the number of characters *actually* written,
// not the number of characters that *would* have been printed were buflen unlimited.
extern mDNSu32 mDNS_vsnprintf(char *sbuffer, mDNSu32 buflen, const char *fmt, va_list arg);
extern mDNSu32 mDNS_snprintf(char *sbuffer, mDNSu32 buflen, const char *fmt, ...) IS_A_PRINTF_STYLE_FUNCTION(3,4);
extern mDNSu32 NumCacheRecordsForInterfaceID(const mDNS *const m, mDNSInterfaceID id);
extern char *DNSTypeName(mDNSu16 rrtype);
extern char *GetRRDisplayString_rdb(const ResourceRecord *const rr, const RDataBody *const rd1, char *const buffer);
#define RRDisplayString(m, rr) GetRRDisplayString_rdb(rr, &(rr)->rdata->u, (m)->MsgBuffer)
#define ARDisplayString(m, rr) GetRRDisplayString_rdb(&(rr)->resrec, &(rr)->resrec.rdata->u, (m)->MsgBuffer)
#define CRDisplayString(m, rr) GetRRDisplayString_rdb(&(rr)->resrec, &(rr)->resrec.rdata->u, (m)->MsgBuffer)
extern mDNSBool mDNSSameAddress(const mDNSAddr *ip1, const mDNSAddr *ip2);
extern void IncrementLabelSuffix(domainlabel *name, mDNSBool RichText);
extern mDNSBool mDNSv4AddrIsRFC1918(mDNSv4Addr *addr); // returns true for RFC1918 private addresses
#define mDNSAddrIsRFC1918(X) ((X)->type == mDNSAddrType_IPv4 && mDNSv4AddrIsRFC1918(&(X)->ip.v4))
#define mDNSSameIPPort(A,B) ((A).NotAnInteger == (B).NotAnInteger)
#define mDNSSameOpaque16(A,B) ((A).NotAnInteger == (B).NotAnInteger)
#define mDNSSameOpaque32(A,B) ((A).NotAnInteger == (B).NotAnInteger)
#define mDNSSameOpaque64(A,B) ((A)->l[0] == (B)->l[0] && (A)->l[1] == (B)->l[1])
#define mDNSSameIPv4Address(A,B) ((A).NotAnInteger == (B).NotAnInteger)
#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])
#define mDNSSameEthAddress(A,B) ((A)->w[0] == (B)->w[0] && (A)->w[1] == (B)->w[1] && (A)->w[2] == (B)->w[2])
#define mDNSIPPortIsZero(A) ((A).NotAnInteger == 0)
#define mDNSOpaque16IsZero(A) ((A).NotAnInteger == 0)
#define mDNSOpaque64IsZero(A) (((A)->l[0] | (A)->l[1] ) == 0)
#define mDNSIPv4AddressIsZero(A) ((A).NotAnInteger == 0)
#define mDNSIPv6AddressIsZero(A) (((A).l[0] | (A).l[1] | (A).l[2] | (A).l[3]) == 0)
#define mDNSEthAddressIsZero(A) (((A).w[0] | (A).w[1] | (A).w[2] ) == 0)
#define mDNSIPv4AddressIsOnes(A) ((A).NotAnInteger == 0xFFFFFFFF)
#define mDNSIPv6AddressIsOnes(A) (((A).l[0] & (A).l[1] & (A).l[2] & (A).l[3]) == 0xFFFFFFFF)
#define mDNSAddressIsAllDNSLinkGroup(X) ( \
((X)->type == mDNSAddrType_IPv4 && mDNSSameIPv4Address((X)->ip.v4, AllDNSLinkGroup_v4.ip.v4)) || \
((X)->type == mDNSAddrType_IPv6 && mDNSSameIPv6Address((X)->ip.v6, AllDNSLinkGroup_v6.ip.v6)) )
#define mDNSAddressIsZero(X) ( \
((X)->type == mDNSAddrType_IPv4 && mDNSIPv4AddressIsZero((X)->ip.v4)) || \
((X)->type == mDNSAddrType_IPv6 && mDNSIPv6AddressIsZero((X)->ip.v6)) )
#define mDNSAddressIsValidNonZero(X) ( \
((X)->type == mDNSAddrType_IPv4 && !mDNSIPv4AddressIsZero((X)->ip.v4)) || \
((X)->type == mDNSAddrType_IPv6 && !mDNSIPv6AddressIsZero((X)->ip.v6)) )
#define mDNSAddressIsOnes(X) ( \
((X)->type == mDNSAddrType_IPv4 && mDNSIPv4AddressIsOnes((X)->ip.v4)) || \
((X)->type == mDNSAddrType_IPv6 && mDNSIPv6AddressIsOnes((X)->ip.v6)) )
#define mDNSAddressIsValid(X) ( \
((X)->type == mDNSAddrType_IPv4) ? !(mDNSIPv4AddressIsZero((X)->ip.v4) || mDNSIPv4AddressIsOnes((X)->ip.v4)) : \
((X)->type == mDNSAddrType_IPv6) ? !(mDNSIPv6AddressIsZero((X)->ip.v6) || mDNSIPv6AddressIsOnes((X)->ip.v6)) : mDNSfalse)
#define mDNSv4AddressIsLinkLocal(X) ((X)->b[0] == 169 && (X)->b[1] == 254)
#define mDNSv6AddressIsLinkLocal(X) ((X)->b[0] == 0xFE && ((X)->b[1] & 0xC0) == 0x80)
#define mDNSAddressIsLinkLocal(X) ( \
((X)->type == mDNSAddrType_IPv4) ? mDNSv4AddressIsLinkLocal(&(X)->ip.v4) : \
((X)->type == mDNSAddrType_IPv6) ? mDNSv6AddressIsLinkLocal(&(X)->ip.v6) : mDNSfalse)
// ***************************************************************************
#if 0
#pragma mark -
#pragma mark - Authentication Support
#endif
// Unicast DNS and Dynamic Update specific Client Calls
//
// mDNS_SetSecretForDomain tells the core to authenticate (via TSIG with an HMAC_MD5 hash of the shared secret)
// when dynamically updating a given zone (and its subdomains). The key used in authentication must be in
// domain name format. The shared secret must be a null-terminated base64 encoded string. A minimum size of
// 16 bytes (128 bits) is recommended for an MD5 hash as per RFC 2485.
// Calling this routine multiple times for a zone replaces previously entered values. Call with a NULL key
// to dissable authentication for the zone.
extern mStatus mDNS_SetSecretForDomain(mDNS *m, DomainAuthInfo *info,
const domainname *domain, const domainname *keyname, const char *b64keydata, mDNSBool AutoTunnel);
extern void RecreateNATMappings(mDNS *const m);
// Hostname/Unicast Interface Configuration
// All hostnames advertised point to one IPv4 address and/or one IPv6 address, set via SetPrimaryInterfaceInfo. Invoking this routine
// updates all existing hostnames to point to the new address.
// A hostname is added via AddDynDNSHostName, which points to the primary interface's v4 and/or v6 addresss
// The status callback is invoked to convey success or failure codes - the callback should not modify the AuthRecord or free memory.
// Added hostnames may be removed (deregistered) via mDNS_RemoveDynDNSHostName.
// Host domains added prior to specification of the primary interface address and computer name will be deferred until
// these values are initialized.
// DNS servers used to resolve unicast queries are specified by mDNS_AddDNSServer.
// For "split" DNS configurations, in which queries for different domains are sent to different servers (e.g. VPN and external),
// a domain may be associated with a DNS server. For standard configurations, specify the root label (".") or NULL.
extern void mDNS_AddDynDNSHostName(mDNS *m, const domainname *fqdn, mDNSRecordCallback *StatusCallback, const void *StatusContext);
extern void mDNS_RemoveDynDNSHostName(mDNS *m, const domainname *fqdn);
extern void mDNS_SetPrimaryInterfaceInfo(mDNS *m, const mDNSAddr *v4addr, const mDNSAddr *v6addr, const mDNSAddr *router);
extern DNSServer *mDNS_AddDNSServer(mDNS *const m, const domainname *d, const mDNSInterfaceID interface, const mDNSAddr *addr, const mDNSIPPort port);
extern void PenalizeDNSServer(mDNS *const m, DNSQuestion *q, mDNSBool QueryFail);
extern void mDNS_AddSearchDomain(const domainname *const domain);
// We use ((void *)0) here instead of mDNSNULL to avoid compile warnings on gcc 4.2
#define mDNS_AddSearchDomain_CString(X) \
do { domainname d__; if (((X) != (void*)0) && MakeDomainNameFromDNSNameString(&d__, (X)) && d__.c[0]) mDNS_AddSearchDomain(&d__); } while(0)
// Routines called by the core, exported by DNSDigest.c
// Convert an arbitrary base64 encoded key key into an HMAC key (stored in AuthInfo struct)
extern mDNSs32 DNSDigest_ConstructHMACKeyfromBase64(DomainAuthInfo *info, const char *b64key);
// sign a DNS message. The message must be complete, with all values in network byte order. end points to the end
// of the message, and is modified by this routine. numAdditionals is a pointer to the number of additional
// records in HOST byte order, which is incremented upon successful completion of this routine. The function returns
// the new end pointer on success, and NULL on failure.
extern void DNSDigest_SignMessage(DNSMessage *msg, mDNSu8 **end, DomainAuthInfo *info, mDNSu16 tcode);
#define SwapDNSHeaderBytes(M) do { \
(M)->h.numQuestions = (mDNSu16)((mDNSu8 *)&(M)->h.numQuestions )[0] << 8 | ((mDNSu8 *)&(M)->h.numQuestions )[1]; \
(M)->h.numAnswers = (mDNSu16)((mDNSu8 *)&(M)->h.numAnswers )[0] << 8 | ((mDNSu8 *)&(M)->h.numAnswers )[1]; \
(M)->h.numAuthorities = (mDNSu16)((mDNSu8 *)&(M)->h.numAuthorities)[0] << 8 | ((mDNSu8 *)&(M)->h.numAuthorities)[1]; \
(M)->h.numAdditionals = (mDNSu16)((mDNSu8 *)&(M)->h.numAdditionals)[0] << 8 | ((mDNSu8 *)&(M)->h.numAdditionals)[1]; \
} while (0)
#define DNSDigest_SignMessageHostByteOrder(M,E,INFO) \
do { SwapDNSHeaderBytes(M); DNSDigest_SignMessage((M), (E), (INFO), 0); SwapDNSHeaderBytes(M); } while (0)
// verify a DNS message. The message must be complete, with all values in network byte order. end points to the
// end of the record. tsig is a pointer to the resource record that contains the TSIG OPT record. info is
// the matching key to use for verifying the message. This function expects that the additionals member
// of the DNS message header has already had one subtracted from it.
extern mDNSBool DNSDigest_VerifyMessage(DNSMessage *msg, mDNSu8 *end, LargeCacheRecord *tsig, DomainAuthInfo *info, mDNSu16 *rcode, mDNSu16 *tcode);
// ***************************************************************************
#if 0
#pragma mark -
#pragma mark - PlatformSupport interface
#endif
// This section defines the interface to the Platform Support layer.
// Normal client code should not use any of types defined here, or directly call any of the functions defined here.
// The definitions are placed here because sometimes clients do use these calls indirectly, via other supported client operations.
// For example, AssignDomainName is a macro defined using mDNSPlatformMemCopy()
// Every platform support module must provide the following functions.
// mDNSPlatformInit() typically opens a communication endpoint, and starts listening for mDNS packets.
// When Setup is complete, the platform support layer calls mDNSCoreInitComplete().
// mDNSPlatformSendUDP() sends one UDP packet
// When a packet is received, the PlatformSupport code calls mDNSCoreReceive()
// mDNSPlatformClose() tidies up on exit
//
// Note: mDNSPlatformMemAllocate/mDNSPlatformMemFree are only required for handling oversized resource records and unicast DNS.
// If your target platform has a well-defined specialized application, and you know that all the records it uses
// are InlineCacheRDSize or less, then you can just make a simple mDNSPlatformMemAllocate() stub that always returns
// NULL. InlineCacheRDSize is a compile-time constant, which is set by default to 68. If you need to handle records
// a little larger than this and you don't want to have to implement run-time allocation and freeing, then you
// can raise the value of this constant to a suitable value (at the expense of increased memory usage).
//
// USE CAUTION WHEN CALLING mDNSPlatformRawTime: The m->timenow_adjust correction factor needs to be added
// Generally speaking:
// Code that's protected by the main mDNS lock should just use the m->timenow value
// Code outside the main mDNS lock should use mDNS_TimeNow(m) to get properly adjusted time
// In certain cases there may be reasons why it's necessary to get the time without taking the lock first
// (e.g. inside the routines that are doing the locking and unlocking, where a call to get the lock would result in a
// recursive loop); in these cases use mDNS_TimeNow_NoLock(m) to get mDNSPlatformRawTime with the proper correction factor added.
//
// mDNSPlatformUTC returns the time, in seconds, since Jan 1st 1970 UTC and is required for generating TSIG records
extern mStatus mDNSPlatformInit (mDNS *const m);
extern void mDNSPlatformClose (mDNS *const m);
extern mStatus mDNSPlatformSendUDP(const mDNS *const m, const void *const msg, const mDNSu8 *const end,
mDNSInterfaceID InterfaceID, UDPSocket *src, const mDNSAddr *dst, mDNSIPPort dstport);
extern void mDNSPlatformLock (const mDNS *const m);
extern void mDNSPlatformUnlock (const mDNS *const m);
extern void mDNSPlatformStrCopy ( void *dst, const void *src);
extern mDNSu32 mDNSPlatformStrLen ( const void *src);
extern void mDNSPlatformMemCopy ( void *dst, const void *src, mDNSu32 len);
extern mDNSBool mDNSPlatformMemSame (const void *dst, const void *src, mDNSu32 len);
extern void mDNSPlatformMemZero ( void *dst, mDNSu32 len);
#if APPLE_OSX_mDNSResponder && MACOSX_MDNS_MALLOC_DEBUGGING
#define mDNSPlatformMemAllocate(X) mallocL(#X, X)
#else
extern void * mDNSPlatformMemAllocate (mDNSu32 len);
#endif
extern void mDNSPlatformMemFree (void *mem);
// If the platform doesn't have a strong PRNG, we define a naive multiply-and-add based on a seed
// from the platform layer. Long-term, we should embed an arc4 implementation, but the strength
// will still depend on the randomness of the seed.
#if !defined(_PLATFORM_HAS_STRONG_PRNG_) && (_BUILDING_XCODE_PROJECT_ || defined(_WIN32))
#define _PLATFORM_HAS_STRONG_PRNG_ 1
#endif
#if _PLATFORM_HAS_STRONG_PRNG_
extern mDNSu32 mDNSPlatformRandomNumber(void);
#else
extern mDNSu32 mDNSPlatformRandomSeed (void);
#endif // _PLATFORM_HAS_STRONG_PRNG_
extern mStatus mDNSPlatformTimeInit (void);
extern mDNSs32 mDNSPlatformRawTime (void);
extern mDNSs32 mDNSPlatformUTC (void);
#define mDNS_TimeNow_NoLock(m) (mDNSPlatformRawTime() + (m)->timenow_adjust)
#if MDNS_DEBUGMSGS
extern void mDNSPlatformWriteDebugMsg(const char *msg);
#endif
extern void mDNSPlatformWriteLogMsg(const char *ident, const char *msg, mDNSLogLevel_t loglevel);
#if APPLE_OSX_mDNSResponder
// Utility function for ASL logging
mDNSexport void mDNSASLLog(uuid_t *uuid, const char *subdomain, const char *result, const char *signature, const char *fmt, ...);
#endif
// Platform support modules should provide the following functions to map between opaque interface IDs
// and interface indexes in order to support the DNS-SD API. If your target platform does not support
// multiple interfaces and/or does not support the DNS-SD API, these functions can be empty.
extern mDNSInterfaceID mDNSPlatformInterfaceIDfromInterfaceIndex(mDNS *const m, mDNSu32 ifindex);
extern mDNSu32 mDNSPlatformInterfaceIndexfromInterfaceID(mDNS *const m, mDNSInterfaceID id);
// Every platform support module must provide the following functions if it is to support unicast DNS
// and Dynamic Update.
// All TCP socket operations implemented by the platform layer MUST NOT BLOCK.
// mDNSPlatformTCPConnect initiates a TCP connection with a peer, adding the socket descriptor to the
// main event loop. The return value indicates whether the connection succeeded, failed, or is pending
// (i.e. the call would block.) On return, the descriptor parameter is set to point to the connected socket.
// The TCPConnectionCallback is subsequently invoked when the connection
// completes (in which case the ConnectionEstablished parameter is true), or data is available for
// reading on the socket (indicated by the ConnectionEstablished parameter being false.) If the connection
// asynchronously fails, the TCPConnectionCallback should be invoked as usual, with the error being
// returned in subsequent calls to PlatformReadTCP or PlatformWriteTCP. (This allows for platforms
// with limited asynchronous error detection capabilities.) PlatformReadTCP and PlatformWriteTCP must
// return the number of bytes read/written, 0 if the call would block, and -1 if an error. PlatformReadTCP
// should set the closed argument if the socket has been closed.
// PlatformTCPCloseConnection must close the connection to the peer and remove the descriptor from the
// event loop. CloseConnectin may be called at any time, including in a ConnectionCallback.
typedef enum
{
kTCPSocketFlags_Zero = 0,
kTCPSocketFlags_UseTLS = (1 << 0)
} TCPSocketFlags;
typedef void (*TCPConnectionCallback)(TCPSocket *sock, void *context, mDNSBool ConnectionEstablished, mStatus err);
extern TCPSocket *mDNSPlatformTCPSocket(mDNS *const m, TCPSocketFlags flags, mDNSIPPort *port); // creates a TCP socket
extern TCPSocket *mDNSPlatformTCPAccept(TCPSocketFlags flags, int sd);
extern int mDNSPlatformTCPGetFD(TCPSocket *sock);
extern mStatus mDNSPlatformTCPConnect(TCPSocket *sock, const mDNSAddr *dst, mDNSOpaque16 dstport, mDNSInterfaceID InterfaceID,
TCPConnectionCallback callback, void *context);
extern void mDNSPlatformTCPCloseConnection(TCPSocket *sock);
extern long mDNSPlatformReadTCP(TCPSocket *sock, void *buf, unsigned long buflen, mDNSBool *closed);
extern long mDNSPlatformWriteTCP(TCPSocket *sock, const char *msg, unsigned long len);
extern UDPSocket *mDNSPlatformUDPSocket(mDNS *const m, const mDNSIPPort requestedport);
extern void mDNSPlatformUDPClose(UDPSocket *sock);
extern void mDNSPlatformReceiveBPF_fd(mDNS *const m, int fd);
extern void mDNSPlatformUpdateProxyList(mDNS *const m, const mDNSInterfaceID InterfaceID);
extern void mDNSPlatformSendRawPacket(const void *const msg, const mDNSu8 *const end, mDNSInterfaceID InterfaceID);
extern void mDNSPlatformSetLocalARP(const mDNSv4Addr *const tpa, const mDNSEthAddr *const tha, mDNSInterfaceID InterfaceID);
extern void mDNSPlatformSourceAddrForDest(mDNSAddr *const src, const mDNSAddr *const dst);
// mDNSPlatformTLSSetupCerts/mDNSPlatformTLSTearDownCerts used by dnsextd
extern mStatus mDNSPlatformTLSSetupCerts(void);
extern void mDNSPlatformTLSTearDownCerts(void);
// Platforms that support unicast browsing and dynamic update registration for clients who do not specify a domain
// in browse/registration calls must implement these routines to get the "default" browse/registration list.
extern void mDNSPlatformSetDNSConfig(mDNS *const m, mDNSBool setservers, mDNSBool setsearch, domainname *const fqdn, DNameListElem **RegDomains, DNameListElem **BrowseDomains);
extern mStatus mDNSPlatformGetPrimaryInterface(mDNS *const m, mDNSAddr *v4, mDNSAddr *v6, mDNSAddr *router);
extern void mDNSPlatformDynDNSHostNameStatusChanged(const domainname *const dname, const mStatus status);
#ifdef _LEGACY_NAT_TRAVERSAL_
// Support for legacy NAT traversal protocols, implemented by the platform layer and callable by the core.
extern void LNT_SendDiscoveryMsg(mDNS *m);
extern void LNT_ConfigureRouterInfo(mDNS *m, const mDNSInterfaceID InterfaceID, mDNSu8 *data, mDNSu16 len);
extern mStatus LNT_GetExternalAddress(mDNS *m);
extern mStatus LNT_MapPort(mDNS *m, NATTraversalInfo *n);
extern mStatus LNT_UnmapPort(mDNS *m, NATTraversalInfo *n);
extern void LNT_ClearState(mDNS *const m);
#endif // _LEGACY_NAT_TRAVERSAL_
// The core mDNS code provides these functions, for the platform support code to call at appropriate times
//
// mDNS_SetFQDN() is called once on startup (typically from mDNSPlatformInit())
// and then again on each subsequent change of the host name.
//
// mDNS_RegisterInterface() is used by the platform support layer to inform mDNSCore of what
// physical and/or logical interfaces are available for sending and receiving packets.
// Typically it is called on startup for each available interface, but register/deregister may be
// called again later, on multiple occasions, to inform the core of interface configuration changes.
// If set->Advertise is set non-zero, then mDNS_RegisterInterface() also registers the standard
// resource records that should be associated with every publicised IP address/interface:
// -- Name-to-address records (A/AAAA)
// -- Address-to-name records (PTR)
// -- Host information (HINFO)
// IMPORTANT: The specified mDNSInterfaceID MUST NOT be 0, -1, or -2; these values have special meaning
// mDNS_RegisterInterface does not result in the registration of global hostnames via dynamic update -
// see mDNS_SetPrimaryInterfaceInfo, mDNS_AddDynDNSHostName, etc. for this purpose.
// Note that the set may be deallocated immediately after it is deregistered via mDNS_DeegisterInterface.
//
// mDNS_RegisterDNS() is used by the platform support layer to provide the core with the addresses of
// available domain name servers for unicast queries/updates. RegisterDNS() should be called once for
// each name server, typically at startup, or when a new name server becomes available. DeregiterDNS()
// must be called whenever a registered name server becomes unavailable. DeregisterDNSList deregisters
// all registered servers. mDNS_DNSRegistered() returns true if one or more servers are registered in the core.
//
// mDNSCoreInitComplete() is called when the platform support layer is finished.
// Typically this is at the end of mDNSPlatformInit(), but may be later
// (on platforms like OT that allow asynchronous initialization of the networking stack).
//
// mDNSCoreReceive() is called when a UDP packet is received
//
// mDNSCoreMachineSleep() is called when the machine sleeps or wakes
// (This refers to heavyweight laptop-style sleep/wake that disables network access,
// not lightweight second-by-second CPU power management modes.)
extern void mDNS_SetFQDN(mDNS *const m);
extern void mDNS_ActivateNetWake_internal (mDNS *const m, NetworkInterfaceInfo *set);
extern void mDNS_DeactivateNetWake_internal(mDNS *const m, NetworkInterfaceInfo *set);
extern mStatus mDNS_RegisterInterface (mDNS *const m, NetworkInterfaceInfo *set, mDNSBool flapping);
extern void mDNS_DeregisterInterface(mDNS *const m, NetworkInterfaceInfo *set, mDNSBool flapping);
extern void mDNSCoreInitComplete(mDNS *const m, mStatus result);
extern void mDNSCoreReceive(mDNS *const m, void *const msg, const mDNSu8 *const end,
const mDNSAddr *const srcaddr, const mDNSIPPort srcport,
const mDNSAddr *const dstaddr, const mDNSIPPort dstport, const mDNSInterfaceID InterfaceID);
extern void mDNSCoreRestartQueries(mDNS *const m);
extern mDNSBool mDNSCoreHaveAdvertisedMulticastServices(mDNS *const m);
extern void mDNSCoreMachineSleep(mDNS *const m, mDNSBool wake);
extern mDNSBool mDNSCoreReadyForSleep(mDNS *m, mDNSs32 now);
extern mDNSs32 mDNSCoreIntervalToNextWake(mDNS *const m, mDNSs32 now);
extern void mDNSCoreBeSleepProxyServer(mDNS *const m, mDNSu8 sps, mDNSu8 port, mDNSu8 marginalpower, mDNSu8 totpower);
extern void mDNSCoreReceiveRawPacket (mDNS *const m, const mDNSu8 *const p, const mDNSu8 *const end, const mDNSInterfaceID InterfaceID);
extern mDNSBool mDNSAddrIsDNSMulticast(const mDNSAddr *ip);
extern CacheRecord *CreateNewCacheEntry(mDNS *const m, const mDNSu32 slot, CacheGroup *cg);
extern void GrantCacheExtensions(mDNS *const m, DNSQuestion *q, mDNSu32 lease);
extern void MakeNegativeCacheRecord(mDNS *const m, CacheRecord *const cr,
const domainname *const name, const mDNSu32 namehash, const mDNSu16 rrtype, const mDNSu16 rrclass, mDNSu32 ttl_seconds, mDNSInterfaceID InterfaceID);
extern void CompleteDeregistration(mDNS *const m, AuthRecord *rr);
extern void FindSPSInCache(mDNS *const m, const DNSQuestion *const q, const CacheRecord *sps[3]);
#define PrototypeSPSName(X) ((X)[0] >= 11 && (X)[3] == '-' && (X)[ 4] == '9' && (X)[ 5] == '9' && \
(X)[6] == '-' && (X)[ 7] == '9' && (X)[ 8] == '9' && \
(X)[9] == '-' && (X)[10] == '9' && (X)[11] == '9' )
#define ValidSPSName(X) ((X)[0] >= 5 && mDNSIsDigit((X)[1]) && mDNSIsDigit((X)[2]) && mDNSIsDigit((X)[4]) && mDNSIsDigit((X)[5]))
#define SPSMetric(X) (!ValidSPSName(X) || PrototypeSPSName(X) ? 1000000 : \
((X)[1]-'0') * 100000 + ((X)[2]-'0') * 10000 + ((X)[4]-'0') * 1000 + ((X)[5]-'0') * 100 + ((X)[7]-'0') * 10 + ((X)[8]-'0'))
extern void AnswerCurrentQuestionWithResourceRecord(mDNS *const m, CacheRecord *const rr, const QC_result AddRecord);
extern char *InterfaceNameForID(mDNS *const m, const mDNSInterfaceID InterfaceID);
// For now this AutoTunnel stuff is specific to Mac OS X.
// In the future, if there's demand, we may see if we can abstract it out cleanly into the platform layer
#if APPLE_OSX_mDNSResponder
extern void AutoTunnelCallback(mDNS *const m, DNSQuestion *question, const ResourceRecord *const answer, QC_result AddRecord);
extern void AddNewClientTunnel(mDNS *const m, DNSQuestion *const q);
extern void SetupLocalAutoTunnelInterface_internal(mDNS *const m);
extern void UpdateAutoTunnelDomainStatuses(const mDNS *const m);
extern mStatus ActivateLocalProxy(mDNS *const m, char *ifname);
#endif
// ***************************************************************************
#if 0
#pragma mark -
#pragma mark - Compile-Time assertion checks
#endif
// Some C compiler cleverness. We can make the compiler check certain things for
// us, and report compile-time errors if anything is wrong. The usual way to do
// this would be to use a run-time "if" statement, but then you don't find out
// what's wrong until you run the software. This way, if the assertion condition
// is false, the array size is negative, and the complier complains immediately.
struct CompileTimeAssertionChecks_mDNS
{
// Check that the compiler generated our on-the-wire packet format structure definitions
// properly packed, without adding padding bytes to align fields on 32-bit or 64-bit boundaries.
char assert0[(sizeof(rdataSRV) == 262 ) ? 1 : -1];
char assert1[(sizeof(DNSMessageHeader) == 12 ) ? 1 : -1];
char assert2[(sizeof(DNSMessage) == 12+AbsoluteMaxDNSMessageData) ? 1 : -1];
char assert3[(sizeof(mDNSs8) == 1 ) ? 1 : -1];
char assert4[(sizeof(mDNSu8) == 1 ) ? 1 : -1];
char assert5[(sizeof(mDNSs16) == 2 ) ? 1 : -1];
char assert6[(sizeof(mDNSu16) == 2 ) ? 1 : -1];
char assert7[(sizeof(mDNSs32) == 4 ) ? 1 : -1];
char assert8[(sizeof(mDNSu32) == 4 ) ? 1 : -1];
char assert9[(sizeof(mDNSOpaque16) == 2 ) ? 1 : -1];
char assertA[(sizeof(mDNSOpaque32) == 4 ) ? 1 : -1];
char assertB[(sizeof(mDNSOpaque128) == 16 ) ? 1 : -1];
char assertC[(sizeof(CacheRecord ) == sizeof(CacheGroup) ) ? 1 : -1];
char assertD[(sizeof(int) >= 4 ) ? 1 : -1];
char assertE[(StandardAuthRDSize >= 256 ) ? 1 : -1];
char assertF[(sizeof(EthernetHeader) == 14 ) ? 1 : -1];
char assertG[(sizeof(ARP_EthIP ) == 28 ) ? 1 : -1];
char assertH[(sizeof(IPv4Header ) == 20 ) ? 1 : -1];
char assertI[(sizeof(IPv6Header ) == 40 ) ? 1 : -1];
char assertJ[(sizeof(IPv6ND ) == 24 ) ? 1 : -1];
char assertK[(sizeof(UDPHeader ) == 8 ) ? 1 : -1];
char assertL[(sizeof(IKEHeader ) == 28 ) ? 1 : -1];
char assertM[(sizeof(TCPHeader ) == 20 ) ? 1 : -1];
// Check our structures are reasonable sizes. Including overly-large buffers, or embedding
// other overly-large structures instead of having a pointer to them, can inadvertently
// cause structure sizes (and therefore memory usage) to balloon unreasonably.
char sizecheck_RDataBody [(sizeof(RDataBody) == 264) ? 1 : -1];
char sizecheck_ResourceRecord [(sizeof(ResourceRecord) <= 56) ? 1 : -1];
char sizecheck_AuthRecord [(sizeof(AuthRecord) <= 1000) ? 1 : -1];
char sizecheck_CacheRecord [(sizeof(CacheRecord) <= 176) ? 1 : -1];
char sizecheck_CacheGroup [(sizeof(CacheGroup) <= 176) ? 1 : -1];
char sizecheck_DNSQuestion [(sizeof(DNSQuestion) <= 728) ? 1 : -1];
char sizecheck_ZoneData [(sizeof(ZoneData) <= 1560) ? 1 : -1];
char sizecheck_NATTraversalInfo [(sizeof(NATTraversalInfo) <= 192) ? 1 : -1];
char sizecheck_HostnameInfo [(sizeof(HostnameInfo) <= 2800) ? 1 : -1];
char sizecheck_DNSServer [(sizeof(DNSServer) <= 312) ? 1 : -1];
char sizecheck_NetworkInterfaceInfo[(sizeof(NetworkInterfaceInfo) <= 5968) ? 1 : -1];
char sizecheck_ServiceRecordSet [(sizeof(ServiceRecordSet) <= 5500) ? 1 : -1];
char sizecheck_DomainAuthInfo [(sizeof(DomainAuthInfo) <= 5500) ? 1 : -1];
char sizecheck_ServiceInfoQuery [(sizeof(ServiceInfoQuery) <= 2944) ? 1 : -1];
#if APPLE_OSX_mDNSResponder
char sizecheck_ClientTunnel [(sizeof(ClientTunnel) <= 1072) ? 1 : -1];
#endif
};
// ***************************************************************************
#ifdef __cplusplus
}
#endif
#endif