/* -*- Mode: C; tab-width: 4 -*- * * Copyright (c) 2002-2004 Apple Computer, Inc. All rights reserved. * * @APPLE_LICENSE_HEADER_START@ * * This file contains Original Code and/or Modifications of Original Code * as defined in and that are subject to the Apple Public Source License * Version 2.0 (the 'License'). You may not use this file except in * compliance with the License. Please obtain a copy of the License at * http://www.opensource.apple.com/apsl/ and read it before using this * file. * * The Original Code and all software distributed under the License are * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. * Please see the License for the specific language governing rights and * limitations under the License. * * @APPLE_LICENSE_HEADER_END@ * * Formatting notes: * This code follows the "Whitesmiths style" C indentation rules. Plenty of discussion * on C indentation can be found on the web, such as , * but for the sake of brevity here I will say just this: Curly braces are not syntactially * part of an "if" statement; they are the beginning and ending markers of a compound statement; * therefore common sense dictates that if they are part of a compound statement then they * should be indented to the same level as everything else in that compound statement. * Indenting curly braces at the same level as the "if" implies that curly braces are * part of the "if", which is false. (This is as misleading as people who write "char* x,y;" * thinking that variables x and y are both of type "char*" -- and anyone who doesn't * understand why variable y is not of type "char*" just proves the point that poor code * layout leads people to unfortunate misunderstandings about how the C language really works.) Change History (most recent first): $Log: Identify.c,v $ Revision 1.33 2004/11/30 22:37:00 cheshire Update copyright dates and add "Mode: C; tab-width: 4" headers Revision 1.32 2004/10/19 21:33:21 cheshire Cannot resolve non-local registrations using the mach API Added flag 'kDNSServiceFlagsForceMulticast'. Passing through an interface id for a unicast name doesn't force multicast unless you set this flag to indicate explicitly that this is what you want Revision 1.31 2004/10/16 00:17:00 cheshire Replace IP TTL 255 check with local subnet source address check Revision 1.30 2004/09/21 23:29:51 cheshire DNSServiceResolve should delay sending packets Revision 1.29 2004/09/17 01:08:53 cheshire Renamed mDNSClientAPI.h to mDNSEmbeddedAPI.h The name "mDNSClientAPI.h" is misleading to new developers looking at this code. The interfaces declared in that file are ONLY appropriate to single-address-space embedded applications. For clients on general-purpose computers, the interfaces defined in dns_sd.h should be used. Revision 1.28 2004/09/17 00:31:52 cheshire For consistency with ipv6, renamed rdata field 'ip' to 'ipv4' Revision 1.27 2004/09/16 01:58:22 cheshire Fix compiler warnings Revision 1.26 2004/08/24 21:55:07 cheshire Don't try to build IPv6 code on systems that don't have IPv6 Revision 1.25 2004/07/20 23:42:37 cheshire Update to use only "_services._dns-sd._udp.local." meta-query for service enumeration Revision 1.24 2004/06/15 02:39:47 cheshire When displaying error message, only show command name, not entire path Revision 1.23 2004/05/18 23:51:26 cheshire Tidy up all checkin comments to use consistent "" format for bug numbers Revision 1.22 2004/04/20 22:43:28 cheshire Use _services._dns-sd._udp query, as documented in Revision 1.21 2004/01/28 21:38:57 cheshire Also ask target host for _services._mdns._udp.local. list Revision 1.20 2004/01/28 19:04:38 cheshire Fix Ctrl-C handling when multiple targets are specified Revision 1.19 2004/01/28 03:49:30 cheshire Enhanced mDNSIdentify to make use of new targeted-query capability Revision 1.18 2004/01/27 19:06:51 cheshire Remove workaround for WWDC 2003 bug; no one has run that buggy build for a long time Revision 1.17 2004/01/22 03:57:00 cheshire Use the new meta-interface mDNSInterface_ForceMCast. This restores mDNSIdentify's ability to use multicast queries with non-link-local target addresses, like 17.x.x.x. Revision 1.16 2004/01/22 00:03:32 cheshire Add while() loop so that a list of targets may be specified on the command line Revision 1.15 2004/01/21 21:55:06 cheshire Don't need to wait for timeout once we've got the information we wanted Revision 1.14 2003/12/17 00:51:22 cheshire Changed mDNSNetMonitor and mDNSIdentify to link the object files instead of #including the "DNSCommon.c" "uDNS.c" and source files Revision 1.13 2003/12/13 03:05:28 ksekar : DynDNS: Unicast query of service records Revision 1.12 2003/11/14 21:27:09 cheshire : Security: Crashing bug in mDNSResponder Fix code that should use buffer size MAX_ESCAPED_DOMAIN_NAME (1005) instead of 256-byte buffers. Revision 1.11 2003/10/30 19:26:38 cheshire Fix warnings on certain compilers Revision 1.10 2003/09/02 20:38:57 cheshire #include for Linux Revision 1.9 2003/08/14 23:57:46 cheshire Report if there is no answer at all from the target host Revision 1.8 2003/08/14 02:19:55 cheshire Split generic ResourceRecord type into two separate types: AuthRecord and CacheRecord Revision 1.7 2003/08/12 19:56:26 cheshire Update to APSL 2.0 Revision 1.6 2003/08/06 01:46:18 cheshire Distinguish no answer from partial answer Revision 1.5 2003/08/05 23:56:26 cheshire Update code to compile with the new mDNSCoreReceive() function that requires a TTL (Right now mDNSPosix.c just reports 255 -- we should fix this) Revision 1.4 2003/08/04 17:24:48 cheshire Combine the three separate A/AAAA/HINFO queries into a single qtype "ANY" query Revision 1.3 2003/08/04 17:14:08 cheshire Do both AAAA queries in parallel Revision 1.2 2003/08/02 02:25:13 cheshire Multiple improvements: Now displays host's name, and all v4 and v6 addresses, as well as HINFO record Revision 1.1 2003/08/01 02:20:02 cheshire Add mDNSIdentify tool, used to discover what version of mDNSResponder a particular host is running */ //************************************************************************************************************* // Incorporate mDNS.c functionality // We want to use the functionality provided by "mDNS.c", // except we'll sneak a peek at the packets before forwarding them to the normal mDNSCoreReceive() routine #define mDNSCoreReceive __MDNS__mDNSCoreReceive #include "mDNS.c" #undef mDNSCoreReceive //************************************************************************************************************* // Headers #include #include #include #include #include #include #include // For n_long, required by below #include // For IPTOS_LOWDELAY etc. #include #include #include "mDNSEmbeddedAPI.h"// Defines the interface to the mDNS core code #include "mDNSPosix.h" // Defines the specific types needed to run mDNS on this platform #include "ExampleClientApp.h" //************************************************************************************************************* // Globals static mDNS mDNSStorage; // mDNS core uses this to store its globals static mDNS_PlatformSupport PlatformStorage; // Stores this platform's globals #define RR_CACHE_SIZE 500 static CacheRecord gRRCache[RR_CACHE_SIZE]; static volatile int StopNow; // 0 means running, 1 means stop because we got an answer, 2 means stop because of Ctrl-C static volatile int NumAnswers, NumAddr, NumAAAA, NumHINFO; static char hostname[MAX_ESCAPED_DOMAIN_NAME], hardware[256], software[256]; static mDNSAddr lastsrc, hostaddr, target; static mDNSOpaque16 lastid, id; //************************************************************************************************************* // Utilities // Special version of printf that knows how to print IP addresses, DNS-format name strings, etc. mDNSlocal mDNSu32 mprintf(const char *format, ...) IS_A_PRINTF_STYLE_FUNCTION(1,2); mDNSlocal mDNSu32 mprintf(const char *format, ...) { mDNSu32 length; unsigned char buffer[512]; va_list ptr; va_start(ptr,format); length = mDNS_vsnprintf((char *)buffer, sizeof(buffer), format, ptr); va_end(ptr); printf("%s", buffer); return(length); } //************************************************************************************************************* // Main code mDNSexport void mDNSCoreReceive(mDNS *const m, DNSMessage *const msg, const mDNSu8 *const end, const mDNSAddr *const srcaddr, const mDNSIPPort srcport, const mDNSAddr *const dstaddr, const mDNSIPPort dstport, const mDNSInterfaceID InterfaceID) { (void)dstaddr; // Unused // Snag copy of header ID, then call through lastid = msg->h.id; lastsrc = *srcaddr; // We *want* to allow off-net unicast responses here. // For now, the simplest way to allow that is to pretend it was received via multicast so that mDNSCore doesn't reject the packet __MDNS__mDNSCoreReceive(m, msg, end, srcaddr, srcport, &AllDNSLinkGroup_v4, dstport, InterfaceID); } static void NameCallback(mDNS *const m, DNSQuestion *question, const ResourceRecord *const answer, mDNSBool AddRecord) { (void)m; // Unused (void)question; // Unused (void)AddRecord;// Unused if (!id.NotAnInteger) id = lastid; if (answer->rrtype == kDNSType_PTR || answer->rrtype == kDNSType_CNAME) { ConvertDomainNameToCString(&answer->rdata->u.name, hostname); StopNow = 1; mprintf("%##s %s %##s\n", answer->name.c, DNSTypeName(answer->rrtype), answer->rdata->u.name.c); } } static void InfoCallback(mDNS *const m, DNSQuestion *question, const ResourceRecord *const answer, mDNSBool AddRecord) { (void)m; // Unused (void)question; // Unused (void)AddRecord;// Unused if (answer->rrtype == kDNSType_A) { if (!id.NotAnInteger) id = lastid; NumAnswers++; NumAddr++; mprintf("%##s %s %.4a\n", answer->name.c, DNSTypeName(answer->rrtype), &answer->rdata->u.ipv4); hostaddr.type = mDNSAddrType_IPv4; // Prefer v4 target to v6 target, for now hostaddr.ip.v4 = answer->rdata->u.ipv4; } else if (answer->rrtype == kDNSType_AAAA) { if (!id.NotAnInteger) id = lastid; NumAnswers++; NumAAAA++; mprintf("%##s %s %.16a\n", answer->name.c, DNSTypeName(answer->rrtype), &answer->rdata->u.ipv6); if (!hostaddr.type) // Prefer v4 target to v6 target, for now { hostaddr.type = mDNSAddrType_IPv6; hostaddr.ip.v6 = answer->rdata->u.ipv6; } } else if (answer->rrtype == kDNSType_HINFO) { mDNSu8 *p = answer->rdata->u.data; strncpy(hardware, (char*)(p+1), p[0]); hardware[p[0]] = 0; p += 1 + p[0]; strncpy(software, (char*)(p+1), p[0]); software[p[0]] = 0; NumAnswers++; NumHINFO++; } // If we've got everything we're looking for, don't need to wait any more if (NumHINFO && (NumAddr || NumAAAA)) StopNow = 1; } static void ServicesCallback(mDNS *const m, DNSQuestion *question, const ResourceRecord *const answer, mDNSBool AddRecord) { (void)m; // Unused (void)question; // Unused (void)AddRecord;// Unused // Right now the mDNSCore targeted-query code is incomplete -- // it issues targeted queries, but accepts answers from anywhere // For now, we'll just filter responses here so we don't get confused by responses from someone else if (answer->rrtype == kDNSType_PTR && mDNSSameAddress(&lastsrc, &target)) { NumAnswers++; NumAddr++; mprintf("%##s %s %##s\n", answer->name.c, DNSTypeName(answer->rrtype), answer->rdata->u.name.c); StopNow = 1; } } mDNSexport void WaitForAnswer(mDNS *const m, int seconds) { struct timeval end; gettimeofday(&end, NULL); end.tv_sec += seconds; StopNow = 0; NumAnswers = 0; while (!StopNow) { int nfds = 0; fd_set readfds; struct timeval now, remain = end; int result; FD_ZERO(&readfds); gettimeofday(&now, NULL); if (remain.tv_usec < now.tv_usec) { remain.tv_usec += 1000000; remain.tv_sec--; } if (remain.tv_sec < now.tv_sec) return; remain.tv_usec -= now.tv_usec; remain.tv_sec -= now.tv_sec; mDNSPosixGetFDSet(m, &nfds, &readfds, &remain); result = select(nfds, &readfds, NULL, NULL, &remain); if (result >= 0) mDNSPosixProcessFDSet(m, &readfds); else if (errno != EINTR) StopNow = 2; } } mDNSlocal mStatus StartQuery(DNSQuestion *q, char *qname, mDNSu16 qtype, const mDNSAddr *target, mDNSQuestionCallback callback) { if (qname) MakeDomainNameFromDNSNameString(&q->qname, qname); q->Target = target ? *target : zeroAddr; q->TargetPort = MulticastDNSPort; q->TargetQID = zeroID; q->InterfaceID = mDNSInterface_Any; q->qtype = qtype; q->qclass = kDNSClass_IN; q->LongLived = mDNSfalse; q->ExpectUnique = mDNStrue; q->ForceMCast = mDNStrue; // Query via multicast, even for apparently uDNS names like 1.1.1.17.in-addr.arpa. q->QuestionCallback = callback; q->QuestionContext = NULL; //mprintf("%##s %s ?\n", q->qname.c, DNSTypeName(qtype)); return(mDNS_StartQuery(&mDNSStorage, q)); } mDNSlocal void DoOneQuery(DNSQuestion *q, char *qname, mDNSu16 qtype, const mDNSAddr *target, mDNSQuestionCallback callback) { mStatus status = StartQuery(q, qname, qtype, target, callback); if (status != mStatus_NoError) StopNow = 2; else { WaitForAnswer(&mDNSStorage, 4); mDNS_StopQuery(&mDNSStorage, q); } } mDNSlocal int DoQuery(DNSQuestion *q, char *qname, mDNSu16 qtype, const mDNSAddr *target, mDNSQuestionCallback callback) { DoOneQuery(q, qname, qtype, target, callback); if (StopNow == 0 && target && target->type) { mprintf("%##s %s Trying multicast\n", q->qname.c, DNSTypeName(q->qtype)); DoOneQuery(q, qname, qtype, NULL, callback); } if (StopNow == 0 && NumAnswers == 0) mprintf("%##s %s *** No Answer ***\n", q->qname.c, DNSTypeName(q->qtype)); return(StopNow); } mDNSlocal void HandleSIG(int signal) { (void)signal; // Unused debugf("%s",""); debugf("HandleSIG"); StopNow = 2; } mDNSexport int main(int argc, char **argv) { const char *progname = strrchr(argv[0], '/') ? strrchr(argv[0], '/') + 1 : argv[0]; int this_arg = 1; mStatus status; struct in_addr s4; #if HAVE_IPV6 struct in6_addr s6; #endif char buffer[256]; DNSQuestion q; if (argc < 2) goto usage; // Since this is a special command-line tool, we want LogMsg() errors to go to stderr, not syslog mDNS_DebugMode = mDNStrue; // Initialise the mDNS core. status = mDNS_Init(&mDNSStorage, &PlatformStorage, gRRCache, RR_CACHE_SIZE, mDNS_Init_DontAdvertiseLocalAddresses, mDNS_Init_NoInitCallback, mDNS_Init_NoInitCallbackContext); if (status) { fprintf(stderr, "Daemon start: mDNS_Init failed %ld\n", status); return(status); } signal(SIGINT, HandleSIG); // SIGINT is what you get for a Ctrl-C signal(SIGTERM, HandleSIG); while (this_arg < argc) { char *arg = argv[this_arg++]; if (this_arg > 2) printf("\n"); lastid = id = zeroID; hostaddr = target = zeroAddr; hostname[0] = hardware[0] = software[0] = 0; NumAddr = NumAAAA = NumHINFO = 0; if (inet_pton(AF_INET, arg, &s4) == 1) { mDNSu8 *p = (mDNSu8 *)&s4; mDNS_snprintf(buffer, sizeof(buffer), "%d.%d.%d.%d.in-addr.arpa.", p[3], p[2], p[1], p[0]); printf("%s\n", buffer); target.type = mDNSAddrType_IPv4; target.ip.v4.NotAnInteger = s4.s_addr; DoQuery(&q, buffer, kDNSType_PTR, &target, NameCallback); if (StopNow == 2) break; } #if HAVE_IPV6 else if (inet_pton(AF_INET6, arg, &s6) == 1) { int i; mDNSu8 *p = (mDNSu8 *)&s6; for (i = 0; i < 16; i++) { static const char hexValues[] = "0123456789ABCDEF"; buffer[i * 4 ] = hexValues[p[15-i] & 0x0F]; buffer[i * 4 + 1] = '.'; buffer[i * 4 + 2] = hexValues[p[15-i] >> 4]; buffer[i * 4 + 3] = '.'; } mDNS_snprintf(&buffer[64], sizeof(buffer)-64, "ip6.arpa."); target.type = mDNSAddrType_IPv6; bcopy(&s6, &target.ip.v6, sizeof(target.ip.v6)); DoQuery(&q, buffer, kDNSType_PTR, &target, NameCallback); if (StopNow == 2) break; } #endif else strcpy(hostname, arg); // Now we have the host name; get its A, AAAA, and HINFO if (hostname[0]) DoQuery(&q, hostname, kDNSQType_ANY, &target, InfoCallback); if (StopNow == 2) break; if (hardware[0] || software[0]) { DNSQuestion q1; printf("HINFO Hardware: %s\n", hardware); printf("HINFO Software: %s\n", software); // We need to make sure the services query is targeted if (target.type == 0) target = hostaddr; StartQuery(&q1, "_services._dns-sd._udp.local.", kDNSQType_ANY, &target, ServicesCallback); WaitForAnswer(&mDNSStorage, 4); mDNS_StopQuery(&mDNSStorage, &q1); if (StopNow == 2) break; } else if (NumAnswers) { printf("Host has no HINFO record; Best guess is "); if (id.b[1]) printf("mDNSResponder-%d\n", id.b[1]); else if (NumAAAA) printf("very early Panther build (mDNSResponder-33 or earlier)\n"); else printf("Jaguar version of mDNSResponder with no IPv6 support\n"); } else printf("Incorrect dot-local hostname, address, or no mDNSResponder running on that machine\n"); } mDNS_Close(&mDNSStorage); return(0); usage: fprintf(stderr, "%s or or ...\n", progname); return(-1); }