/* * Copyright (c) 2002-2003 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: daemon.c,v $ Revision 1.134.2.6 2004/04/06 19:50:36 cheshire mDNSResponder will not launch if "nobody" user doesn't exist. After more discussion, we've decided to use userid -2 if "nobody" user doesn't exist. Revision 1.134.2.5 2004/04/03 01:29:07 cheshire mDNSResponder will not launch if "nobody" user doesn't exist. If "nobody" user doesn't exist, log a message and continue as "root" Revision 1.134.2.4 2004/04/02 21:50:21 cheshire Fix errors in comments Revision 1.134.2.3 2003/12/12 01:21:30 cheshire mDNSResponder should not run as root Revision 1.134.2.2 2003/12/05 00:03:35 cheshire Use buffer size MAX_ESCAPED_DOMAIN_NAME instead of 256 Revision 1.134.2.1 2003/12/03 11:00:09 cheshire Update "mDNSResponderVersion" mechanism to allow dots so we can do mDNSResponder-58.1 for SUPan Revision 1.134 2003/08/21 20:01:37 cheshire Traffic reduction: Detect long-lived Resolve() calls, and report them in syslog Revision 1.133 2003/08/20 23:39:31 cheshire Review syslog messages, and remove as appropriate Revision 1.132 2003/08/20 01:44:56 cheshire Fix errors in LogOperation() calls (only used for debugging) Revision 1.131 2003/08/19 05:39:43 cheshire SIGINFO dump should include resolves started by DNSServiceQueryRecord Revision 1.130 2003/08/16 03:39:01 cheshire InterfaceID -1 indicates "local only" Revision 1.129 2003/08/15 20:16:03 cheshire mDNSResponder takes too much RPRVT We want to avoid touching the rdata pages, so we don't page them in. 1. RDLength was stored with the rdata, which meant touching the page just to find the length. Moved this from the RData to the ResourceRecord object. 2. To avoid unnecessarily touching the rdata just to compare it, compute a hash of the rdata and store the hash in the ResourceRecord object. Revision 1.128 2003/08/14 19:30:36 cheshire Include list of cache records in SIGINFO output Revision 1.127 2003/08/14 02:18:21 cheshire Split generic ResourceRecord type into two separate types: AuthRecord and CacheRecord Revision 1.126 2003/08/12 19:56:25 cheshire Update to APSL 2.0 Revision 1.125 2003/08/08 18:36:04 cheshire Only need to revalidate on interface removal on platforms that have the PhantomInterfaces bug Revision 1.124 2003/07/25 18:28:23 cheshire Minor fix to error messages in syslog: Display string parameters with quotes Revision 1.123 2003/07/23 17:45:28 cheshire mDNSResponder leaks a bit Don't allocate memory for the reply until after we've verified that the reply is valid Revision 1.122 2003/07/23 00:00:04 cheshire Add comments Revision 1.121 2003/07/20 03:38:51 ksekar Bug #: 3320722 Completed support for Unix-domain socket based API. Revision 1.120 2003/07/18 00:30:00 cheshire Remove mDNSResponder version from packet header and use HINFO record instead Revision 1.119 2003/07/17 19:08:58 cheshire Remove calls to enable obsolete UDS code Revision 1.118 2003/07/15 21:12:28 cheshire Added extra debugging checks in validatelists() (not used in final shipping version) Revision 1.117 2003/07/15 01:55:15 cheshire Need to implement service registration with subtypes Revision 1.116 2003/07/02 21:19:51 cheshire Update copyright notices, etc., in source code comments Revision 1.115 2003/07/02 02:41:24 cheshire mDNSResponder needs to start with a smaller cache and then grow it as needed Revision 1.114 2003/07/01 21:10:20 cheshire Reinstate checkin 1.111, inadvertently overwritten by checkin 1.112 Revision 1.113 2003/06/28 17:27:43 vlubet Redirect standard input, standard output, and standard error file descriptors to /dev/null just like any other well behaved daemon Revision 1.112 2003/06/25 23:42:19 ksekar Bug #: : Feature: New Rendezvous APIs (#7875) Reviewed by: Stuart Cheshire Added files necessary to implement Unix domain sockets based enhanced Rendezvous APIs, and integrated with existing Mach-port based daemon. Revision 1.111 2003/06/11 01:02:43 cheshire mDNSResponder binary compatibility Make single binary that can run on both Jaguar and Panther. Revision 1.110 2003/06/10 01:14:11 cheshire New APIs require a mDNSPlatformInterfaceIDfromInterfaceIndex() call Revision 1.109 2003/06/06 19:53:43 cheshire For clarity, rename question fields name/rrtype/rrclass as qname/qtype/qclass (Global search-and-replace; no functional change to code execution.) Revision 1.108 2003/06/06 14:08:06 cheshire For clarity, pull body of main while() loop out into a separate function called mDNSDaemonIdle() Revision 1.107 2003/05/29 05:44:55 cheshire Minor fixes to log messages Revision 1.106 2003/05/27 18:30:55 cheshire Need a way to easily examine current mDNSResponder state Dean Reece suggested SIGINFO is more appropriate than SIGHUP Revision 1.105 2003/05/26 03:21:29 cheshire Tidy up address structure naming: mDNSIPAddr => mDNSv4Addr (for consistency with mDNSv6Addr) mDNSAddr.addr.ipv4 => mDNSAddr.ip.v4 mDNSAddr.addr.ipv6 => mDNSAddr.ip.v6 Revision 1.104 2003/05/26 00:42:06 cheshire Temporarily include mDNSResponder version in packets Revision 1.103 2003/05/23 23:07:44 cheshire Must not write to stderr when running as daemon Revision 1.102 2003/05/22 01:32:31 cheshire Fix typo in Log message format string Revision 1.101 2003/05/22 00:26:55 cheshire DNSServiceRegistrationCreate() should return error on dup Modify error message to explain that this is technically legal, but may indicate a bug. Revision 1.100 2003/05/21 21:02:24 ksekar Bug #: : Service should be prefixed Changed kmDNSBootstrapName to "com.apple.mDNSResponderRestart" since we're changing the main Mach message port to "com.apple.mDNSResponder. Revision 1.99 2003/05/21 17:33:49 cheshire Fix warnings (mainly printf format string warnings, like using "%d" where it should say "%lu", etc.) Revision 1.98 2003/05/20 00:33:07 cheshire Need a way to easily examine current mDNSResponder state SIGHUP now writes state summary to syslog Revision 1.97 2003/05/08 00:19:08 cheshire Forgot to set "err = mStatus_BadParamErr" in a couple of places Revision 1.96 2003/05/07 22:10:46 cheshire Add a few more error logging messages Revision 1.95 2003/05/07 19:20:17 cheshire Add version number to mDNSResponder builds Revision 1.94 2003/05/07 00:28:18 cheshire Need to make mDNSResponder more defensive against bad clients Revision 1.93 2003/05/06 00:00:49 cheshire Rationalize naming of domainname manipulation functions Revision 1.92 2003/04/04 20:38:57 cheshire Add $Log header */ #include #include #include #include #include #include #include #include #include "DNSServiceDiscoveryRequestServer.h" #include "DNSServiceDiscoveryReply.h" #include "mDNSClientAPI.h" // Defines the interface to the client layer above #include "mDNSMacOSX.h" // Defines the specific types needed to run mDNS on this platform #include #define ENABLE_UDS 1 //************************************************************************************************************* // Macros // Note: The C preprocessor stringify operator ('#') makes a string from its argument, without macro expansion // e.g. If "version" is #define'd to be "4", then STRINGIFY_AWE(version) will return the string "version", not "4" // To expand "version" to its value before making the string, use STRINGIFY(version) instead #define STRINGIFY_ARGUMENT_WITHOUT_EXPANSION(s) #s #define STRINGIFY(s) STRINGIFY_ARGUMENT_WITHOUT_EXPANSION(s) //************************************************************************************************************* // Globals mDNSexport mDNS mDNSStorage; static mDNS_PlatformSupport PlatformStorage; #define RR_CACHE_SIZE 64 static CacheRecord rrcachestorage[RR_CACHE_SIZE]; static const char PID_FILE[] = "/var/run/mDNSResponder.pid"; static const char kmDNSBootstrapName[] = "com.apple.mDNSResponderRestart"; static mach_port_t client_death_port = MACH_PORT_NULL; static mach_port_t exit_m_port = MACH_PORT_NULL; static mach_port_t info_m_port = MACH_PORT_NULL; static mach_port_t server_priv_port = MACH_PORT_NULL; // mDNS Mach Message Timeout, in milliseconds. // We need this to be short enough that we don't deadlock the mDNSResponder if a client // fails to service its mach message queue, but long enough to give a well-written // client a chance to service its mach message queue without getting cut off. // Empirically, 50ms seems to work, so we set the timeout to 250ms to give // even extra-slow clients a fair chance before we cut them off. #define MDNS_MM_TIMEOUT 250 static int restarting_via_mach_init = 0; #if MDNS_DEBUGMSGS int debug_mode = 1; #else int debug_mode = 0; #endif //************************************************************************************************************* // Active client list structures typedef struct DNSServiceDomainEnumeration_struct DNSServiceDomainEnumeration; struct DNSServiceDomainEnumeration_struct { DNSServiceDomainEnumeration *next; mach_port_t ClientMachPort; DNSQuestion dom; // Question asking for domains DNSQuestion def; // Question asking for default domain }; typedef struct DNSServiceBrowserResult_struct DNSServiceBrowserResult; struct DNSServiceBrowserResult_struct { DNSServiceBrowserResult *next; int resultType; domainname result; }; typedef struct DNSServiceBrowser_struct DNSServiceBrowser; struct DNSServiceBrowser_struct { DNSServiceBrowser *next; mach_port_t ClientMachPort; DNSQuestion q; DNSServiceBrowserResult *results; mDNSs32 lastsuccess; }; typedef struct DNSServiceResolver_struct DNSServiceResolver; struct DNSServiceResolver_struct { DNSServiceResolver *next; mach_port_t ClientMachPort; ServiceInfoQuery q; ServiceInfo i; mDNSs32 ReportTime; }; typedef struct DNSServiceRegistration_struct DNSServiceRegistration; struct DNSServiceRegistration_struct { DNSServiceRegistration *next; mach_port_t ClientMachPort; mDNSBool autoname; mDNSBool autorename; domainlabel name; ServiceRecordSet s; // Don't add any fields after ServiceRecordSet. // This is where the implicit extra space goes if we allocate an oversized ServiceRecordSet object }; static DNSServiceDomainEnumeration *DNSServiceDomainEnumerationList = NULL; static DNSServiceBrowser *DNSServiceBrowserList = NULL; static DNSServiceResolver *DNSServiceResolverList = NULL; static DNSServiceRegistration *DNSServiceRegistrationList = NULL; //************************************************************************************************************* // General Utility Functions #if MACOSX_MDNS_MALLOC_DEBUGGING char _malloc_options[] = "AXZ"; static void validatelists(mDNS *const m) { DNSServiceDomainEnumeration *e; DNSServiceBrowser *b; DNSServiceResolver *l; DNSServiceRegistration *r; AuthRecord *rr; CacheRecord *cr; DNSQuestion *q; mDNSs32 slot; for (e = DNSServiceDomainEnumerationList; e; e=e->next) if (e->ClientMachPort == 0 || e->ClientMachPort == (mach_port_t)~0) LogMsg("!!!! DNSServiceDomainEnumerationList: %p is garbage (%X) !!!!", e, e->ClientMachPort); for (b = DNSServiceBrowserList; b; b=b->next) if (b->ClientMachPort == 0 || b->ClientMachPort == (mach_port_t)~0) LogMsg("!!!! DNSServiceBrowserList: %p is garbage (%X) !!!!", b, b->ClientMachPort); for (l = DNSServiceResolverList; l; l=l->next) if (l->ClientMachPort == 0 || l->ClientMachPort == (mach_port_t)~0) LogMsg("!!!! DNSServiceResolverList: %p is garbage (%X) !!!!", l, l->ClientMachPort); for (r = DNSServiceRegistrationList; r; r=r->next) if (r->ClientMachPort == 0 || r->ClientMachPort == (mach_port_t)~0) LogMsg("!!!! DNSServiceRegistrationList: %p is garbage (%X) !!!!", r, r->ClientMachPort); for (rr = m->ResourceRecords; rr; rr=rr->next) if (rr->RecordType == 0 || rr->RecordType == 0xFF) LogMsg("!!!! ResourceRecords list: %p is garbage (%X) !!!!", rr, rr->RecordType); for (rr = m->DuplicateRecords; rr; rr=rr->next) if (rr->RecordType == 0 || rr->RecordType == 0xFF) LogMsg("!!!! DuplicateRecords list: %p is garbage (%X) !!!!", rr, rr->RecordType); for (q = m->Questions; q; q=q->next) if (q->ThisQInterval == (mDNSs32)~0) LogMsg("!!!! Questions list: %p is garbage (%lX) !!!!", q, q->ThisQInterval); for (slot = 0; slot < CACHE_HASH_SLOTS; slot++) for (cr = mDNSStorage.rrcache_hash[slot]; cr; cr=cr->next) if (cr->RecordType == 0 || cr->RecordType == 0xFF) LogMsg("!!!! Cache slot %lu: %p is garbage (%X) !!!!", slot, rr, rr->RecordType); } void *mallocL(char *msg, unsigned int size) { unsigned long *mem = malloc(size+8); if (!mem) { LogMsg("malloc( %s : %d ) failed", msg, size); return(NULL); } else { LogMalloc("malloc( %s : %lu ) = %p", msg, size, &mem[2]); mem[0] = 0xDEAD1234; mem[1] = size; //bzero(&mem[2], size); memset(&mem[2], 0xFF, size); validatelists(&mDNSStorage); return(&mem[2]); } } void freeL(char *msg, void *x) { if (!x) LogMsg("free( %s @ NULL )!", msg); else { unsigned long *mem = ((unsigned long *)x) - 2; if (mem[0] != 0xDEAD1234) { LogMsg("free( %s @ %p ) !!!! NOT ALLOCATED !!!!", msg, &mem[2]); return; } if (mem[1] > 8000) { LogMsg("free( %s : %ld @ %p) too big!", msg, mem[1], &mem[2]); return; } LogMalloc("free( %s : %ld @ %p)", msg, mem[1], &mem[2]); //bzero(mem, mem[1]+8); memset(mem, 0xFF, mem[1]+8); validatelists(&mDNSStorage); free(mem); } } #endif //************************************************************************************************************* // Client Death Detection mDNSlocal void FreeDNSServiceRegistration(DNSServiceRegistration *x) { while (x->s.Extras) { ExtraResourceRecord *extras = x->s.Extras; x->s.Extras = x->s.Extras->next; if (extras->r.resrec.rdata != &extras->r.rdatastorage) freeL("Extra RData", extras->r.resrec.rdata); freeL("ExtraResourceRecord", extras); } if (x->s.RR_TXT.resrec.rdata != &x->s.RR_TXT.rdatastorage) freeL("TXT RData", x->s.RR_TXT.resrec.rdata); if (x->s.SubTypes) freeL("ServiceSubTypes", x->s.SubTypes); freeL("DNSServiceRegistration", x); } // AbortClient finds whatever client is identified by the given Mach port, // stops whatever operation that client was doing, and frees its memory. // In the case of a service registration, the actual freeing may be deferred // until we get the mStatus_MemFree message, if necessary mDNSlocal void AbortClient(mach_port_t ClientMachPort, void *m) { DNSServiceDomainEnumeration **e = &DNSServiceDomainEnumerationList; DNSServiceBrowser **b = &DNSServiceBrowserList; DNSServiceResolver **l = &DNSServiceResolverList; DNSServiceRegistration **r = &DNSServiceRegistrationList; while (*e && (*e)->ClientMachPort != ClientMachPort) e = &(*e)->next; if (*e) { DNSServiceDomainEnumeration *x = *e; *e = (*e)->next; if (m && m != x) LogMsg("%5d: DNSServiceDomainEnumeration(%##s) STOP; WARNING m %p != x %p", ClientMachPort, x->dom.qname.c, m, x); else LogOperation("%5d: DNSServiceDomainEnumeration(%##s) STOP", ClientMachPort, x->dom.qname.c); mDNS_StopGetDomains(&mDNSStorage, &x->dom); mDNS_StopGetDomains(&mDNSStorage, &x->def); freeL("DNSServiceDomainEnumeration", x); return; } while (*b && (*b)->ClientMachPort != ClientMachPort) b = &(*b)->next; if (*b) { DNSServiceBrowser *x = *b; *b = (*b)->next; if (m && m != x) LogMsg("%5d: DNSServiceBrowser(%##s) STOP; WARNING m %p != x %p", ClientMachPort, x->q.qname.c, m, x); else LogOperation("%5d: DNSServiceBrowser(%##s) STOP", ClientMachPort, x->q.qname.c); mDNS_StopBrowse(&mDNSStorage, &x->q); while (x->results) { DNSServiceBrowserResult *r = x->results; x->results = x->results->next; freeL("DNSServiceBrowserResult", r); } freeL("DNSServiceBrowser", x); return; } while (*l && (*l)->ClientMachPort != ClientMachPort) l = &(*l)->next; if (*l) { DNSServiceResolver *x = *l; *l = (*l)->next; if (m && m != x) LogMsg("%5d: DNSServiceResolver(%##s) STOP; WARNING m %p != x %p", ClientMachPort, x->i.name.c, m, x); else LogOperation("%5d: DNSServiceResolver(%##s) STOP", ClientMachPort, x->i.name.c); mDNS_StopResolveService(&mDNSStorage, &x->q); freeL("DNSServiceResolver", x); return; } while (*r && (*r)->ClientMachPort != ClientMachPort) r = &(*r)->next; if (*r) { DNSServiceRegistration *x = *r; *r = (*r)->next; x->autorename = mDNSfalse; if (m && m != x) LogMsg("%5d: DNSServiceRegistration(%##s) STOP; WARNING m %p != x %p", ClientMachPort, x->s.RR_SRV.resrec.name.c, m, x); else LogOperation("%5d: DNSServiceRegistration(%##s) STOP", ClientMachPort, x->s.RR_SRV.resrec.name.c); // If mDNS_DeregisterService() returns mStatus_NoError, that means that the service was found in the list, // is sending its goodbye packet, and we'll get an mStatus_MemFree message when we can free the memory. // If mDNS_DeregisterService() returns an error, it means that the service had already been removed from // the list, so we should go ahead and free the memory right now if (mDNS_DeregisterService(&mDNSStorage, &x->s) != mStatus_NoError) FreeDNSServiceRegistration(x); return; } LogMsg("%5d: died or deallocated, but no record of client can be found!", ClientMachPort); } #define AbortBlockedClient(C,MSG,M) AbortClientWithLogMessage((C), "stopped accepting Mach messages", " (" MSG ")", (M)) mDNSlocal void AbortClientWithLogMessage(mach_port_t c, char *reason, char *msg, void *m) { DNSServiceDomainEnumeration *e = DNSServiceDomainEnumerationList; DNSServiceBrowser *b = DNSServiceBrowserList; DNSServiceResolver *l = DNSServiceResolverList; DNSServiceRegistration *r = DNSServiceRegistrationList; while (e && e->ClientMachPort != c) e = e->next; while (b && b->ClientMachPort != c) b = b->next; while (l && l->ClientMachPort != c) l = l->next; while (r && r->ClientMachPort != c) r = r->next; if (e) LogMsg("%5d: DomainEnumeration(%##s) %s%s", c, e->dom.qname.c, reason, msg); else if (b) LogMsg("%5d: Browser(%##s) %s%s", c, b->q.qname.c, reason, msg); else if (l) LogMsg("%5d: Resolver(%##s) %s%s", c, l->i.name.c, reason, msg); else if (r) LogMsg("%5d: Registration(%##s) %s%s", c, r->s.RR_SRV.resrec.name.c, reason, msg); else LogMsg("%5d: (%s) %s, but no record of client can be found!", c, reason, msg); AbortClient(c, m); } mDNSlocal mDNSBool CheckForExistingClient(mach_port_t c) { DNSServiceDomainEnumeration *e = DNSServiceDomainEnumerationList; DNSServiceBrowser *b = DNSServiceBrowserList; DNSServiceResolver *l = DNSServiceResolverList; DNSServiceRegistration *r = DNSServiceRegistrationList; while (e && e->ClientMachPort != c) e = e->next; while (b && b->ClientMachPort != c) b = b->next; while (l && l->ClientMachPort != c) l = l->next; while (r && r->ClientMachPort != c) r = r->next; if (e) LogMsg("%5d: DomainEnumeration(%##s) already exists!", c, e->dom.qname.c); if (b) LogMsg("%5d: Browser(%##s) already exists!", c, b->q.qname.c); if (l) LogMsg("%5d: Resolver(%##s) already exists!", c, l->i.name.c); if (r) LogMsg("%5d: Registration(%##s) already exists!", c, r->s.RR_SRV.resrec.name.c); return(e || b || l || r); } mDNSlocal void ClientDeathCallback(CFMachPortRef unusedport, void *voidmsg, CFIndex size, void *info) { mach_msg_header_t *msg = (mach_msg_header_t *)voidmsg; (void)unusedport; // Unused (void)size; // Unused (void)info; // Unused if (msg->msgh_id == MACH_NOTIFY_DEAD_NAME) { const mach_dead_name_notification_t *const deathMessage = (mach_dead_name_notification_t *)msg; AbortClient(deathMessage->not_port, NULL); /* Deallocate the send right that came in the dead name notification */ mach_port_destroy( mach_task_self(), deathMessage->not_port ); } } mDNSlocal void EnableDeathNotificationForClient(mach_port_t ClientMachPort, void *m) { mach_port_t prev; kern_return_t r = mach_port_request_notification(mach_task_self(), ClientMachPort, MACH_NOTIFY_DEAD_NAME, 0, client_death_port, MACH_MSG_TYPE_MAKE_SEND_ONCE, &prev); // If the port already died while we were thinking about it, then abort the operation right away if (r != KERN_SUCCESS) AbortClientWithLogMessage(ClientMachPort, "died/deallocated before we could enable death notification", "", m); } //************************************************************************************************************* // Domain Enumeration mDNSlocal void FoundDomain(mDNS *const m, DNSQuestion *question, const ResourceRecord *const answer, mDNSBool AddRecord) { kern_return_t status; #pragma unused(m) char buffer[MAX_ESCAPED_DOMAIN_NAME]; DNSServiceDomainEnumerationReplyResultType rt; DNSServiceDomainEnumeration *x = (DNSServiceDomainEnumeration *)question->QuestionContext; debugf("FoundDomain: %##s PTR %##s", answer->name.c, answer->rdata->u.name.c); if (answer->rrtype != kDNSType_PTR) return; if (!x) { debugf("FoundDomain: DNSServiceDomainEnumeration is NULL"); return; } if (AddRecord) { if (question == &x->dom) rt = DNSServiceDomainEnumerationReplyAddDomain; else rt = DNSServiceDomainEnumerationReplyAddDomainDefault; } else { if (question == &x->dom) rt = DNSServiceDomainEnumerationReplyRemoveDomain; else return; } LogOperation("%5d: DNSServiceDomainEnumeration(%##s) %##s %s", x->ClientMachPort, x->dom.qname.c, answer->rdata->u.name.c, !AddRecord ? "RemoveDomain" : question == &x->dom ? "AddDomain" : "AddDomainDefault"); ConvertDomainNameToCString(&answer->rdata->u.name, buffer); status = DNSServiceDomainEnumerationReply_rpc(x->ClientMachPort, rt, buffer, 0, MDNS_MM_TIMEOUT); if (status == MACH_SEND_TIMED_OUT) AbortBlockedClient(x->ClientMachPort, "enumeration", x); } mDNSexport kern_return_t provide_DNSServiceDomainEnumerationCreate_rpc(mach_port_t unusedserver, mach_port_t client, int regDom) { // Check client parameter (void)unusedserver; // Unused mStatus err = mStatus_NoError; const char *errormsg = "Unknown"; if (client == (mach_port_t)-1) { err = mStatus_Invalid; errormsg = "Client id -1 invalid"; goto fail; } if (CheckForExistingClient(client)) { err = mStatus_Invalid; errormsg = "Client id already in use"; goto fail; } mDNS_DomainType dt1 = regDom ? mDNS_DomainTypeRegistration : mDNS_DomainTypeBrowse; mDNS_DomainType dt2 = regDom ? mDNS_DomainTypeRegistrationDefault : mDNS_DomainTypeBrowseDefault; const DNSServiceDomainEnumerationReplyResultType rt = DNSServiceDomainEnumerationReplyAddDomainDefault; // Allocate memory, and handle failure DNSServiceDomainEnumeration *x = mallocL("DNSServiceDomainEnumeration", sizeof(*x)); if (!x) { err = mStatus_NoMemoryErr; errormsg = "No memory"; goto fail; } // Set up object, and link into list x->ClientMachPort = client; x->next = DNSServiceDomainEnumerationList; DNSServiceDomainEnumerationList = x; // Generate initial response verbosedebugf("%5d: Enumerate %s Domains", client, regDom ? "Registration" : "Browsing"); // We always give local. as the initial default browse domain, and then look for more kern_return_t status = DNSServiceDomainEnumerationReply_rpc(x->ClientMachPort, rt, "local.", 0, MDNS_MM_TIMEOUT); if (status == MACH_SEND_TIMED_OUT) { AbortBlockedClient(x->ClientMachPort, "local enumeration", x); return(mStatus_UnknownErr); } // Do the operation err = mDNS_GetDomains(&mDNSStorage, &x->dom, dt1, mDNSInterface_Any, FoundDomain, x); if (!err) err = mDNS_GetDomains(&mDNSStorage, &x->def, dt2, mDNSInterface_Any, FoundDomain, x); if (err) { AbortClient(client, x); errormsg = "mDNS_GetDomains"; goto fail; } // Succeeded: Wrap up and return LogOperation("%5d: DNSServiceDomainEnumeration(%##s) START", client, x->dom.qname.c); EnableDeathNotificationForClient(client, x); return(mStatus_NoError); fail: LogMsg("%5d: DNSServiceDomainEnumeration(%d) failed: %s (%ld)", client, regDom, errormsg, err); return(err); } //************************************************************************************************************* // Browse for services mDNSlocal void FoundInstance(mDNS *const m, DNSQuestion *question, const ResourceRecord *const answer, mDNSBool AddRecord) { (void)m; // Unused if (answer->rrtype != kDNSType_PTR) { LogMsg("FoundInstance: Should not be called with rrtype %d (not a PTR record)", answer->rrtype); return; } domainlabel name; domainname type, domain; if (!DeconstructServiceName(&answer->rdata->u.name, &name, &type, &domain)) { LogMsg("FoundInstance: %##s PTR %##s received from network is not valid DNS-SD service pointer", answer->name.c, answer->rdata->u.name.c); return; } DNSServiceBrowserResult *x = mallocL("DNSServiceBrowserResult", sizeof(*x)); if (!x) { LogMsg("FoundInstance: Failed to allocate memory for result %##s", answer->rdata->u.name.c); return; } verbosedebugf("FoundInstance: %s %##s", AddRecord ? "Add" : "Rmv", answer->rdata->u.name.c); AssignDomainName(x->result, answer->rdata->u.name); if (AddRecord) x->resultType = DNSServiceBrowserReplyAddInstance; else x->resultType = DNSServiceBrowserReplyRemoveInstance; x->next = NULL; DNSServiceBrowser *browser = (DNSServiceBrowser *)question->QuestionContext; DNSServiceBrowserResult **p = &browser->results; while (*p) p = &(*p)->next; *p = x; } mDNSexport kern_return_t provide_DNSServiceBrowserCreate_rpc(mach_port_t unusedserver, mach_port_t client, DNSCString regtype, DNSCString domain) { // Check client parameter (void)unusedserver; // Unused mStatus err = mStatus_NoError; const char *errormsg = "Unknown"; if (client == (mach_port_t)-1) { err = mStatus_Invalid; errormsg = "Client id -1 invalid"; goto fail; } if (CheckForExistingClient(client)) { err = mStatus_Invalid; errormsg = "Client id already in use"; goto fail; } // Check other parameters domainname t, d; if (!regtype[0] || !MakeDomainNameFromDNSNameString(&t, regtype)) { errormsg = "Illegal regtype"; goto badparam; } if (!MakeDomainNameFromDNSNameString(&d, *domain ? domain : "local.")) { errormsg = "Illegal domain"; goto badparam; } // Allocate memory, and handle failure DNSServiceBrowser *x = mallocL("DNSServiceBrowser", sizeof(*x)); if (!x) { err = mStatus_NoMemoryErr; errormsg = "No memory"; goto fail; } // Set up object, and link into list x->ClientMachPort = client; x->results = NULL; x->lastsuccess = 0; x->next = DNSServiceBrowserList; DNSServiceBrowserList = x; // Do the operation LogOperation("%5d: DNSServiceBrowse(%##s%##s) START", client, t.c, d.c); err = mDNS_StartBrowse(&mDNSStorage, &x->q, &t, &d, mDNSInterface_Any, FoundInstance, x); if (err) { AbortClient(client, x); errormsg = "mDNS_StartBrowse"; goto fail; } // Succeeded: Wrap up and return EnableDeathNotificationForClient(client, x); return(mStatus_NoError); badparam: err = mStatus_BadParamErr; fail: LogMsg("%5d: DNSServiceBrowse(\"%s\", \"%s\") failed: %s (%ld)", client, regtype, domain, errormsg, err); return(err); } //************************************************************************************************************* // Resolve Service Info mDNSlocal void FoundInstanceInfo(mDNS *const m, ServiceInfoQuery *query) { kern_return_t status; DNSServiceResolver *x = (DNSServiceResolver *)query->ServiceInfoQueryContext; NetworkInterfaceInfoOSX *ifx = (NetworkInterfaceInfoOSX *)query->info->InterfaceID; if (query->info->InterfaceID == (mDNSInterfaceID)~0) ifx = mDNSNULL; struct sockaddr_storage interface; struct sockaddr_storage address; char cstring[1024]; int i, pstrlen = query->info->TXTinfo[0]; (void)m; // Unused //debugf("FoundInstanceInfo %.4a %.4a %##s", &query->info->InterfaceAddr, &query->info->ip, &query->info->name); if (query->info->TXTlen > sizeof(cstring)) return; bzero(&interface, sizeof(interface)); bzero(&address, sizeof(address)); if (ifx && ifx->ifinfo.ip.type == mDNSAddrType_IPv4) { struct sockaddr_in *sin = (struct sockaddr_in*)&interface; sin->sin_len = sizeof(*sin); sin->sin_family = AF_INET; sin->sin_port = 0; sin->sin_addr.s_addr = ifx->ifinfo.ip.ip.v4.NotAnInteger; } else if (ifx && ifx->ifinfo.ip.type == mDNSAddrType_IPv6) { struct sockaddr_in6 *sin6 = (struct sockaddr_in6*)&interface; sin6->sin6_len = sizeof(*sin6); sin6->sin6_family = AF_INET6; sin6->sin6_flowinfo = 0; sin6->sin6_port = 0; sin6->sin6_addr = *(struct in6_addr*)&ifx->ifinfo.ip.ip.v6; sin6->sin6_scope_id = ifx->scope_id; } if (query->info->ip.type == mDNSAddrType_IPv4) { struct sockaddr_in *sin = (struct sockaddr_in*)&address; sin->sin_len = sizeof(*sin); sin->sin_family = AF_INET; sin->sin_port = query->info->port.NotAnInteger; sin->sin_addr.s_addr = query->info->ip.ip.v4.NotAnInteger; } else { struct sockaddr_in6 *sin6 = (struct sockaddr_in6*)&address; sin6->sin6_len = sizeof(*sin6); sin6->sin6_family = AF_INET6; sin6->sin6_port = query->info->port.NotAnInteger; sin6->sin6_flowinfo = 0; sin6->sin6_addr = *(struct in6_addr*)&query->info->ip.ip.v6; sin6->sin6_scope_id = ifx ? ifx->scope_id : 0; } // The OS X DNSServiceResolverResolve() API is defined using a C-string, // but the mDNS_StartResolveService() call actually returns a packed block of P-strings. // Hence we have to convert the P-string(s) to a C-string before returning the result to the client. // ASCII-1 characters are used in the C-string as boundary markers, // to indicate the boundaries between the original constituent P-strings. for (i=1; iinfo->TXTlen; i++) { if (--pstrlen >= 0) cstring[i-1] = query->info->TXTinfo[i]; else { cstring[i-1] = 1; pstrlen = query->info->TXTinfo[i]; } } cstring[i-1] = 0; // Put the terminating NULL on the end LogOperation("%5d: DNSServiceResolver(%##s) -> %#a:%d", x->ClientMachPort, x->i.name.c, &query->info->ip, (int)query->info->port.b[0] << 8 | query->info->port.b[1]); status = DNSServiceResolverReply_rpc(x->ClientMachPort, (char*)&interface, (char*)&address, cstring, 0, MDNS_MM_TIMEOUT); if (status == MACH_SEND_TIMED_OUT) AbortBlockedClient(x->ClientMachPort, "resolve", x); } mDNSexport kern_return_t provide_DNSServiceResolverResolve_rpc(mach_port_t unusedserver, mach_port_t client, DNSCString name, DNSCString regtype, DNSCString domain) { // Check client parameter (void)unusedserver; // Unused mStatus err = mStatus_NoError; const char *errormsg = "Unknown"; if (client == (mach_port_t)-1) { err = mStatus_Invalid; errormsg = "Client id -1 invalid"; goto fail; } if (CheckForExistingClient(client)) { err = mStatus_Invalid; errormsg = "Client id already in use"; goto fail; } // Check other parameters domainlabel n; domainname t, d, srv; if (!name[0] || !MakeDomainLabelFromLiteralString(&n, name)) { errormsg = "Bad Instance Name"; goto badparam; } if (!regtype[0] || !MakeDomainNameFromDNSNameString(&t, regtype)) { errormsg = "Bad Service Type"; goto badparam; } if (!MakeDomainNameFromDNSNameString(&d, *domain ? domain : "local.")) { errormsg = "Bad Domain"; goto badparam; } if (!ConstructServiceName(&srv, &n, &t, &d)) { errormsg = "Bad Name"; goto badparam; } // Allocate memory, and handle failure DNSServiceResolver *x = mallocL("DNSServiceResolver", sizeof(*x)); if (!x) { err = mStatus_NoMemoryErr; errormsg = "No memory"; goto fail; } // Set up object, and link into list x->ClientMachPort = client; x->i.InterfaceID = mDNSInterface_Any; x->i.name = srv; x->ReportTime = (mDNSPlatformTimeNow() + 130 * mDNSPlatformOneSecond) | 1; // Don't report errors for old iChat ("_ichat._tcp") service. // New iChat ("_presence._tcp") uses DNSServiceQueryRecord() (from /usr/include/dns_sd.h) instead, // and so should other applications that have valid reasons to be doing ongoing record monitoring. if (SameDomainLabel(t.c, (mDNSu8*)"\x6_ichat")) x->ReportTime = 0; x->next = DNSServiceResolverList; DNSServiceResolverList = x; // Do the operation LogOperation("%5d: DNSServiceResolver(%##s) START", client, x->i.name.c); err = mDNS_StartResolveService(&mDNSStorage, &x->q, &x->i, FoundInstanceInfo, x); if (err) { AbortClient(client, x); errormsg = "mDNS_StartResolveService"; goto fail; } // Succeeded: Wrap up and return EnableDeathNotificationForClient(client, x); return(mStatus_NoError); badparam: err = mStatus_BadParamErr; fail: LogMsg("%5d: DNSServiceResolve(\"%s\", \"%s\", \"%s\") failed: %s (%ld)", client, name, regtype, domain, errormsg, err); return(err); } //************************************************************************************************************* // Registration mDNSlocal void RegCallback(mDNS *const m, ServiceRecordSet *const sr, mStatus result) { DNSServiceRegistration *x = (DNSServiceRegistration*)sr->ServiceContext; if (result == mStatus_NoError) { kern_return_t status; LogOperation("%5d: DNSServiceRegistration(%##s) Name Registered", x->ClientMachPort, sr->RR_SRV.resrec.name.c); status = DNSServiceRegistrationReply_rpc(x->ClientMachPort, result, MDNS_MM_TIMEOUT); if (status == MACH_SEND_TIMED_OUT) AbortBlockedClient(x->ClientMachPort, "registration success", x); } else if (result == mStatus_NameConflict) { LogOperation("%5d: DNSServiceRegistration(%##s) Name Conflict", x->ClientMachPort, sr->RR_SRV.resrec.name.c); // Note: By the time we get the mStatus_NameConflict message, the service is already deregistered // and the memory is free, so we don't have to wait for an mStatus_MemFree message as well. if (x->autoname) mDNS_RenameAndReregisterService(m, sr, mDNSNULL); else { // If we get a name conflict, we tell the client about it, and then they are expected to dispose // of their registration in the usual way (which we will catch via client death notification). // If the Mach queue is full, we forcibly abort the client immediately. kern_return_t status = DNSServiceRegistrationReply_rpc(x->ClientMachPort, result, MDNS_MM_TIMEOUT); if (status == MACH_SEND_TIMED_OUT) AbortBlockedClient(x->ClientMachPort, "registration conflict", x); } } else if (result == mStatus_MemFree) { if (x->autorename) { debugf("RegCallback renaming %#s to %#s", x->name.c, mDNSStorage.nicelabel.c); x->autorename = mDNSfalse; x->name = mDNSStorage.nicelabel; mDNS_RenameAndReregisterService(m, &x->s, &x->name); } else { DNSServiceRegistration **r = &DNSServiceRegistrationList; while (*r && *r != x) r = &(*r)->next; if (*r) { LogMsg("RegCallback: %##s Still in DNSServiceRegistration list; removing now", sr->RR_SRV.resrec.name.c); *r = (*r)->next; } LogOperation("%5d: DNSServiceRegistration(%##s) Memory Free", x->ClientMachPort, sr->RR_SRV.resrec.name.c); FreeDNSServiceRegistration(x); } } else LogMsg("%5d: DNSServiceRegistration(%##s) Unknown Result %ld", x->ClientMachPort, sr->RR_SRV.resrec.name.c, result); } mDNSlocal void CheckForDuplicateRegistrations(DNSServiceRegistration *x, domainname *srv, mDNSIPPort port) { int count = 1; // Start with the one we're planning to register, then see if there are any more AuthRecord *rr; for (rr = mDNSStorage.ResourceRecords; rr; rr=rr->next) if (rr->resrec.rrtype == kDNSType_SRV && rr->resrec.rdata->u.srv.port.NotAnInteger == port.NotAnInteger && SameDomainName(&rr->resrec.name, srv)) count++; if (count > 1) LogMsg("%5d: Client application registered %d identical instances of service %##s port %d.", x->ClientMachPort, count, srv->c, (int)port.b[0] << 8 | port.b[1]); } mDNSexport kern_return_t provide_DNSServiceRegistrationCreate_rpc(mach_port_t unusedserver, mach_port_t client, DNSCString name, DNSCString regtype, DNSCString domain, int notAnIntPort, DNSCString txtRecord) { // Check client parameter (void)unusedserver; // Unused mStatus err = mStatus_NoError; const char *errormsg = "Unknown"; if (client == (mach_port_t)-1) { err = mStatus_Invalid; errormsg = "Client id -1 invalid"; goto fail; } if (CheckForExistingClient(client)) { err = mStatus_Invalid; errormsg = "Client id already in use"; goto fail; } // Check for sub-types after the service type AuthRecord *SubTypes = mDNSNULL; mDNSu32 i, NumSubTypes = 0; char *comma = regtype; while (*comma && *comma != ',') comma++; if (*comma) // If we found a comma... { *comma = 0; // Overwrite the first comma with a nul char *p = comma + 1; // Start scanning from the next character while (*p) { if ( !(*p && *p != ',')) { errormsg = "Bad Service SubType"; goto badparam; } while (*p && *p != ',') p++; if (*p) *p++ = 0; NumSubTypes++; } } // Check other parameters domainlabel n; domainname t, d; domainname srv; if (!name[0]) n = mDNSStorage.nicelabel; else if (!MakeDomainLabelFromLiteralString(&n, name)) { errormsg = "Bad Instance Name"; goto badparam; } if (!regtype[0] || !MakeDomainNameFromDNSNameString(&t, regtype)) { errormsg = "Bad Service Type"; goto badparam; } if (!MakeDomainNameFromDNSNameString(&d, *domain ? domain : "local.")) { errormsg = "Bad Domain"; goto badparam; } if (!ConstructServiceName(&srv, &n, &t, &d)) { errormsg = "Bad Name"; goto badparam; } mDNSIPPort port; port.NotAnInteger = notAnIntPort; unsigned char txtinfo[1024] = ""; unsigned int data_len = 0; unsigned int size = sizeof(RDataBody); unsigned char *pstring = &txtinfo[data_len]; char *ptr = txtRecord; // The OS X DNSServiceRegistrationCreate() API is defined using a C-string, // but the mDNS_RegisterService() call actually requires a packed block of P-strings. // Hence we have to convert the C-string to a P-string. // ASCII-1 characters are allowed in the C-string as boundary markers, // so that a single C-string can be used to represent one or more P-strings. while (*ptr) { if (++data_len >= sizeof(txtinfo)) { errormsg = "TXT record too long"; goto badtxt; } if (*ptr == 1) // If this is our boundary marker, start a new P-string { pstring = &txtinfo[data_len]; pstring[0] = 0; ptr++; } else { if (pstring[0] == 255) { errormsg = "TXT record invalid (component longer than 255)"; goto badtxt; } pstring[++pstring[0]] = *ptr++; } } data_len++; if (size < data_len) size = data_len; // Allocate memory, and handle failure DNSServiceRegistration *x = mallocL("DNSServiceRegistration", sizeof(*x) - sizeof(RDataBody) + size); if (!x) { err = mStatus_NoMemoryErr; errormsg = "No memory"; goto fail; } if (NumSubTypes) { SubTypes = mallocL("ServiceSubTypes", NumSubTypes * sizeof(AuthRecord)); if (!SubTypes) { freeL("DNSServiceRegistration", x); err = mStatus_NoMemoryErr; errormsg = "No memory"; goto fail; } for (i = 0; i < NumSubTypes; i++) { comma++; // Advance over the nul character MakeDomainNameFromDNSNameString(&SubTypes[i].resrec.name, comma); while (*comma) comma++; // Advance comma to point to the next terminating nul } } // Set up object, and link into list x->ClientMachPort = client; x->autoname = (!name[0]); x->autorename = mDNSfalse; x->name = n; x->next = DNSServiceRegistrationList; DNSServiceRegistrationList = x; // Do the operation LogOperation("%5d: DNSServiceRegistration(\"%s\", \"%s\", \"%s\") START", x->ClientMachPort, name, regtype, domain); // Some clients use mDNS for lightweight copy protection, registering a pseudo-service with // a port number of zero. When two instances of the protected client are allowed to run on one // machine, we don't want to see misleading "Bogus client" messages in syslog and the console. if (port.NotAnInteger) CheckForDuplicateRegistrations(x, &srv, port); err = mDNS_RegisterService(&mDNSStorage, &x->s, &x->name, &t, &d, // Name, type, domain mDNSNULL, port, // Host and port txtinfo, data_len, // TXT data, length SubTypes, NumSubTypes, // Subtypes mDNSInterface_Any, // Interace ID RegCallback, x); // Callback and context if (err) { AbortClient(client, x); errormsg = "mDNS_RegisterService"; goto fail; } // Succeeded: Wrap up and return EnableDeathNotificationForClient(client, x); return(mStatus_NoError); badtxt: LogMsg("%5d: TXT record: %.100s...", client, txtRecord); badparam: err = mStatus_BadParamErr; fail: LogMsg("%5d: DNSServiceRegister(\"%s\", \"%s\", \"%s\", %d) failed: %s (%ld)", client, name, regtype, domain, notAnIntPort, errormsg, err); return(err); } mDNSlocal void mDNS_StatusCallback(mDNS *const m, mStatus result) { (void)m; // Unused if (result == mStatus_ConfigChanged) { DNSServiceRegistration *r; for (r = DNSServiceRegistrationList; r; r=r->next) if (r->autoname && !SameDomainLabel(r->name.c, mDNSStorage.nicelabel.c)) { debugf("NetworkChanged renaming %#s to %#s", r->name.c, mDNSStorage.nicelabel.c); r->autorename = mDNStrue; mDNS_DeregisterService(&mDNSStorage, &r->s); } } else if (result == mStatus_GrowCache) { // If we've run out of cache space, then double the total cache size and give the memory to mDNSCore mDNSu32 numrecords = m->rrcache_size; CacheRecord *storage = mallocL("mStatus_GrowCache", sizeof(CacheRecord) * numrecords); if (storage) mDNS_GrowCache(&mDNSStorage, storage, numrecords); } } //************************************************************************************************************* // Add / Update / Remove records from existing Registration mDNSexport kern_return_t provide_DNSServiceRegistrationAddRecord_rpc(mach_port_t unusedserver, mach_port_t client, int type, const char *data, mach_msg_type_number_t data_len, uint32_t ttl, natural_t *reference) { // Check client parameter (void)unusedserver; // Unused mStatus err = mStatus_NoError; const char *errormsg = "Unknown"; domainname *name = (domainname *)""; if (client == (mach_port_t)-1) { err = mStatus_Invalid; errormsg = "Client id -1 invalid"; goto fail; } DNSServiceRegistration *x = DNSServiceRegistrationList; while (x && x->ClientMachPort != client) x = x->next; if (!x) { err = mStatus_BadReferenceErr; errormsg = "No such client"; goto fail; } name = &x->s.RR_SRV.resrec.name; // Check other parameters if (data_len > 8192) { err = mStatus_BadParamErr; errormsg = "data_len > 8K"; goto fail; } unsigned int size = sizeof(RDataBody); if (size < data_len) size = data_len; // Allocate memory, and handle failure ExtraResourceRecord *extra = mallocL("ExtraResourceRecord", sizeof(*extra) - sizeof(RDataBody) + size); if (!extra) { err = mStatus_NoMemoryErr; errormsg = "No memory"; goto fail; } // Fill in type, length, and data of new record extra->r.resrec.rrtype = type; extra->r.rdatastorage.MaxRDLength = size; extra->r.resrec.rdlength = data_len; memcpy(&extra->r.rdatastorage.u.data, data, data_len); // Do the operation LogOperation("%5d: DNSServiceRegistrationAddRecord(%##s, type %d, length %d) REF %p", client, x->s.RR_SRV.resrec.name.c, type, data_len, extra); err = mDNS_AddRecordToService(&mDNSStorage, &x->s, extra, &extra->r.rdatastorage, ttl); *reference = (natural_t)extra; if (err) { errormsg = "mDNS_AddRecordToService"; goto fail; } // Succeeded: Wrap up and return return(mStatus_NoError); fail: LogMsg("%5d: DNSServiceRegistrationAddRecord(%##s, type %d, length %d) failed: %s (%ld)", client, name->c, type, data_len, errormsg, err); return(err); } mDNSlocal void UpdateCallback(mDNS *const m, AuthRecord *const rr, RData *OldRData) { (void)m; // Unused if (OldRData != &rr->rdatastorage) freeL("Old RData", OldRData); } mDNSexport kern_return_t provide_DNSServiceRegistrationUpdateRecord_rpc(mach_port_t unusedserver, mach_port_t client, natural_t reference, const char *data, mach_msg_type_number_t data_len, uint32_t ttl) { // Check client parameter (void)unusedserver; // Unused mStatus err = mStatus_NoError; const char *errormsg = "Unknown"; domainname *name = (domainname *)""; if (client == (mach_port_t)-1) { err = mStatus_Invalid; errormsg = "Client id -1 invalid"; goto fail; } DNSServiceRegistration *x = DNSServiceRegistrationList; while (x && x->ClientMachPort != client) x = x->next; if (!x) { err = mStatus_BadReferenceErr; errormsg = "No such client"; goto fail; } name = &x->s.RR_SRV.resrec.name; // Check other parameters if (data_len > 8192) { err = mStatus_BadParamErr; errormsg = "data_len > 8K"; goto fail; } unsigned int size = sizeof(RDataBody); if (size < data_len) size = data_len; // Find the record we're updating. NULL reference means update the primary TXT record AuthRecord *rr = &x->s.RR_TXT; if (reference) // Scan our list to make sure we're updating a valid record that was previously added { ExtraResourceRecord *e = x->s.Extras; while (e && e != (ExtraResourceRecord*)reference) e = e->next; if (!e) { err = mStatus_BadReferenceErr; errormsg = "No such record"; goto fail; } rr = &e->r; } // Allocate memory, and handle failure RData *newrdata = mallocL("RData", sizeof(*newrdata) - sizeof(RDataBody) + size); if (!newrdata) { err = mStatus_NoMemoryErr; errormsg = "No memory"; goto fail; } // Fill in new length, and data newrdata->MaxRDLength = size; memcpy(&newrdata->u, data, data_len); // Do the operation LogOperation("%5d: DNSServiceRegistrationUpdateRecord(%##s, %X, new length %d)", client, x->s.RR_SRV.resrec.name.c, reference, data_len); err = mDNS_Update(&mDNSStorage, rr, ttl, data_len, newrdata, UpdateCallback); if (err) { errormsg = "mDNS_Update"; goto fail; } // Succeeded: Wrap up and return return(mStatus_NoError); fail: LogMsg("%5d: DNSServiceRegistrationUpdateRecord(%##s, %X, %d) failed: %s (%ld)", client, name->c, reference, data_len, errormsg, err); return(err); } mDNSexport kern_return_t provide_DNSServiceRegistrationRemoveRecord_rpc(mach_port_t unusedserver, mach_port_t client, natural_t reference) { // Check client parameter (void)unusedserver; // Unused mStatus err = mStatus_NoError; const char *errormsg = "Unknown"; domainname *name = (domainname *)""; if (client == (mach_port_t)-1) { err = mStatus_Invalid; errormsg = "Client id -1 invalid"; goto fail; } DNSServiceRegistration *x = DNSServiceRegistrationList; while (x && x->ClientMachPort != client) x = x->next; if (!x) { err = mStatus_BadReferenceErr; errormsg = "No such client"; goto fail; } name = &x->s.RR_SRV.resrec.name; // Do the operation LogOperation("%5d: DNSServiceRegistrationRemoveRecord(%##s, %X)", client, x->s.RR_SRV.resrec.name.c, reference); ExtraResourceRecord *extra = (ExtraResourceRecord*)reference; err = mDNS_RemoveRecordFromService(&mDNSStorage, &x->s, extra); if (err) { errormsg = "mDNS_RemoveRecordFromService (No such record)"; goto fail; } // Succeeded: Wrap up and return if (extra->r.resrec.rdata != &extra->r.rdatastorage) freeL("Extra RData", extra->r.resrec.rdata); freeL("ExtraResourceRecord", extra); return(mStatus_NoError); fail: LogMsg("%5d: DNSServiceRegistrationRemoveRecord(%##s, %X) failed: %s (%ld)", client, name->c, reference, errormsg, err); return(err); } //************************************************************************************************************* // Support Code mDNSlocal void DNSserverCallback(CFMachPortRef port, void *msg, CFIndex size, void *info) { mig_reply_error_t *request = msg; mig_reply_error_t *reply; mach_msg_return_t mr; int options; (void)port; // Unused (void)size; // Unused (void)info; // Unused /* allocate a reply buffer */ reply = CFAllocatorAllocate(NULL, provide_DNSServiceDiscoveryRequest_subsystem.maxsize, 0); /* call the MiG server routine */ (void) DNSServiceDiscoveryRequest_server(&request->Head, &reply->Head); if (!(reply->Head.msgh_bits & MACH_MSGH_BITS_COMPLEX) && (reply->RetCode != KERN_SUCCESS)) { if (reply->RetCode == MIG_NO_REPLY) { /* * This return code is a little tricky -- it appears that the * demux routine found an error of some sort, but since that * error would not normally get returned either to the local * user or the remote one, we pretend it's ok. */ CFAllocatorDeallocate(NULL, reply); return; } /* * destroy any out-of-line data in the request buffer but don't destroy * the reply port right (since we need that to send an error message). */ request->Head.msgh_remote_port = MACH_PORT_NULL; mach_msg_destroy(&request->Head); } if (reply->Head.msgh_remote_port == MACH_PORT_NULL) { /* no reply port, so destroy the reply */ if (reply->Head.msgh_bits & MACH_MSGH_BITS_COMPLEX) mach_msg_destroy(&reply->Head); CFAllocatorDeallocate(NULL, reply); return; } /* * send reply. * * We don't want to block indefinitely because the client * isn't receiving messages from the reply port. * If we have a send-once right for the reply port, then * this isn't a concern because the send won't block. * If we have a send right, we need to use MACH_SEND_TIMEOUT. * To avoid falling off the kernel's fast RPC path unnecessarily, * we only supply MACH_SEND_TIMEOUT when absolutely necessary. */ options = MACH_SEND_MSG; if (MACH_MSGH_BITS_REMOTE(reply->Head.msgh_bits) == MACH_MSG_TYPE_MOVE_SEND_ONCE) options |= MACH_SEND_TIMEOUT; mr = mach_msg(&reply->Head, /* msg */ options, /* option */ reply->Head.msgh_size, /* send_size */ 0, /* rcv_size */ MACH_PORT_NULL, /* rcv_name */ MACH_MSG_TIMEOUT_NONE, /* timeout */ MACH_PORT_NULL); /* notify */ /* Has a message error occurred? */ switch (mr) { case MACH_SEND_INVALID_DEST: case MACH_SEND_TIMED_OUT: /* the reply can't be delivered, so destroy it */ mach_msg_destroy(&reply->Head); break; default : /* Includes success case. */ break; } CFAllocatorDeallocate(NULL, reply); } mDNSlocal kern_return_t registerBootstrapService() { kern_return_t status; mach_port_t service_send_port, service_rcv_port; debugf("Registering Bootstrap Service"); /* * See if our service name is already registered and if we have privilege to check in. */ status = bootstrap_check_in(bootstrap_port, (char*)kmDNSBootstrapName, &service_rcv_port); if (status == KERN_SUCCESS) { /* * If so, we must be a followup instance of an already defined server. In that case, * the bootstrap port we inherited from our parent is the server's privilege port, so set * that in case we have to unregister later (which requires the privilege port). */ server_priv_port = bootstrap_port; restarting_via_mach_init = TRUE; } else if (status == BOOTSTRAP_UNKNOWN_SERVICE) { status = bootstrap_create_server(bootstrap_port, "/usr/sbin/mDNSResponder", getuid(), FALSE /* relaunch immediately, not on demand */, &server_priv_port); if (status != KERN_SUCCESS) return status; status = bootstrap_create_service(server_priv_port, (char*)kmDNSBootstrapName, &service_send_port); if (status != KERN_SUCCESS) { mach_port_deallocate(mach_task_self(), server_priv_port); return status; } status = bootstrap_check_in(server_priv_port, (char*)kmDNSBootstrapName, &service_rcv_port); if (status != KERN_SUCCESS) { mach_port_deallocate(mach_task_self(), server_priv_port); mach_port_deallocate(mach_task_self(), service_send_port); return status; } assert(service_send_port == service_rcv_port); } /* * We have no intention of responding to requests on the service port. We are not otherwise * a Mach port-based service. We are just using this mechanism for relaunch facilities. * So, we can dispose of all the rights we have for the service port. We don't destroy the * send right for the server's privileged bootstrap port - in case we have to unregister later. */ mach_port_destroy(mach_task_self(), service_rcv_port); return status; } mDNSlocal kern_return_t destroyBootstrapService() { debugf("Destroying Bootstrap Service"); return bootstrap_register(server_priv_port, (char*)kmDNSBootstrapName, MACH_PORT_NULL); } mDNSlocal void ExitCallback(CFMachPortRef port, void *msg, CFIndex size, void *info) { (void)port; // Unused (void)msg; // Unused (void)size; // Unused (void)info; // Unused /* CacheRecord *rr; int rrcache_active = 0; for (rr = mDNSStorage.rrcache; rr; rr=rr->next) if (CacheRRActive(&mDNSStorage, rr)) rrcache_active++; debugf("ExitCallback: RR Cache now using %d records, %d active", mDNSStorage.rrcache_used, rrcache_active); */ LogMsg("%s stopping", mDNSResponderVersionString); debugf("ExitCallback: destroyBootstrapService"); if (!debug_mode) destroyBootstrapService(); debugf("ExitCallback: Aborting MIG clients"); while (DNSServiceDomainEnumerationList) AbortClient(DNSServiceDomainEnumerationList->ClientMachPort, DNSServiceDomainEnumerationList); while (DNSServiceBrowserList) AbortClient(DNSServiceBrowserList ->ClientMachPort, DNSServiceBrowserList); while (DNSServiceResolverList) AbortClient(DNSServiceResolverList ->ClientMachPort, DNSServiceResolverList); while (DNSServiceRegistrationList) AbortClient(DNSServiceRegistrationList ->ClientMachPort, DNSServiceRegistrationList); debugf("ExitCallback: mDNS_Close"); mDNS_Close(&mDNSStorage); #if ENABLE_UDS if (udsserver_exit() < 0) LogMsg("ExitCallback: udsserver_exit failed"); #endif exit(0); } // Send a mach_msg to ourselves (since that is signal safe) telling us to cleanup and exit mDNSlocal void HandleSIGTERM(int signal) { (void)signal; // Unused debugf(" "); debugf("SIGINT/SIGTERM"); mach_msg_header_t header; header.msgh_bits = MACH_MSGH_BITS(MACH_MSG_TYPE_MAKE_SEND, 0); header.msgh_remote_port = exit_m_port; header.msgh_local_port = MACH_PORT_NULL; header.msgh_size = sizeof(header); header.msgh_id = 0; if (mach_msg_send(&header) != MACH_MSG_SUCCESS) { LogMsg("HandleSIGTERM: mach_msg_send failed; Exiting immediately."); exit(-1); } } mDNSlocal void INFOCallback(CFMachPortRef port, void *msg, CFIndex size, void *info) { (void)port; // Unused (void)msg; // Unused (void)size; // Unused (void)info; // Unused DNSServiceDomainEnumeration *e; DNSServiceBrowser *b; DNSServiceResolver *l; DNSServiceRegistration *r; mDNSs32 slot; CacheRecord *rr; mDNSu32 CacheUsed = 0, CacheActive = 0; LogMsg("%s ---- BEGIN STATE LOG ----", mDNSResponderVersionString); for (slot = 0; slot < CACHE_HASH_SLOTS; slot++) for (rr = mDNSStorage.rrcache_hash[slot]; rr; rr=rr->next) { CacheUsed++; if (rr->CRActiveQuestion) CacheActive++; LogMsg("%s %-5s%-6s%s", rr->CRActiveQuestion ? "Active: " : "Inactive:", DNSTypeName(rr->resrec.rrtype), ((NetworkInterfaceInfoOSX *)rr->resrec.InterfaceID)->ifa_name, GetRRDisplayString(&mDNSStorage, rr)); usleep(1000); // Limit rate a little so we don't flood syslog too fast } if (mDNSStorage.rrcache_totalused != CacheUsed) LogMsg("Cache use mismatch: rrcache_totalused is %lu, true count %lu", mDNSStorage.rrcache_totalused, CacheUsed); if (mDNSStorage.rrcache_active != CacheActive) LogMsg("Cache use mismatch: rrcache_active is %lu, true count %lu", mDNSStorage.rrcache_active, CacheActive); LogMsg("Cache currently contains %lu records; %lu referenced by active questions", CacheUsed, CacheActive); for (e = DNSServiceDomainEnumerationList; e; e=e->next) LogMsg("%5d: DomainEnumeration %##s", e->ClientMachPort, e->dom.qname.c); for (b = DNSServiceBrowserList; b; b=b->next) LogMsg("%5d: ServiceBrowse %##s", b->ClientMachPort, b->q.qname.c); for (l = DNSServiceResolverList; l; l=l->next) LogMsg("%5d: ServiceResolve %##s", l->ClientMachPort, l->i.name.c); for (r = DNSServiceRegistrationList; r; r=r->next) LogMsg("%5d: ServiceRegistration %##s", r->ClientMachPort, r->s.RR_SRV.resrec.name.c); udsserver_info(); LogMsg("%s ---- END STATE LOG ----", mDNSResponderVersionString); } mDNSlocal void HandleSIGINFO(int signal) { (void)signal; // Unused mach_msg_header_t header; header.msgh_bits = MACH_MSGH_BITS(MACH_MSG_TYPE_MAKE_SEND, 0); header.msgh_remote_port = info_m_port; header.msgh_local_port = MACH_PORT_NULL; header.msgh_size = sizeof(header); header.msgh_id = 0; if (mach_msg_send(&header) != MACH_MSG_SUCCESS) LogMsg("HandleSIGINFO: mach_msg_send failed; No state log will be generated."); } mDNSlocal kern_return_t mDNSDaemonInitialize(void) { mStatus err; CFMachPortRef d_port = CFMachPortCreate(NULL, ClientDeathCallback, NULL, NULL); CFMachPortRef s_port = CFMachPortCreate(NULL, DNSserverCallback, NULL, NULL); CFMachPortRef e_port = CFMachPortCreate(NULL, ExitCallback, NULL, NULL); CFMachPortRef i_port = CFMachPortCreate(NULL, INFOCallback, NULL, NULL); mach_port_t m_port = CFMachPortGetPort(s_port); char *MachServerName = mDNSMacOSXSystemBuildNumber(NULL) < 7 ? "DNSServiceDiscoveryServer" : "com.apple.mDNSResponder"; kern_return_t status = bootstrap_register(bootstrap_port, MachServerName, m_port); CFRunLoopSourceRef d_rls = CFMachPortCreateRunLoopSource(NULL, d_port, 0); CFRunLoopSourceRef s_rls = CFMachPortCreateRunLoopSource(NULL, s_port, 0); CFRunLoopSourceRef e_rls = CFMachPortCreateRunLoopSource(NULL, e_port, 0); CFRunLoopSourceRef i_rls = CFMachPortCreateRunLoopSource(NULL, i_port, 0); if (status) { if (status == 1103) LogMsg("Bootstrap_register failed(): A copy of the daemon is apparently already running"); else LogMsg("Bootstrap_register failed(): %s %d", mach_error_string(status), status); return(status); } err = mDNS_Init(&mDNSStorage, &PlatformStorage, rrcachestorage, RR_CACHE_SIZE, mDNS_Init_AdvertiseLocalAddresses, mDNS_StatusCallback, mDNS_Init_NoInitCallbackContext); if (err) { LogMsg("Daemon start: mDNS_Init failed %ld", err); return(err); } client_death_port = CFMachPortGetPort(d_port); exit_m_port = CFMachPortGetPort(e_port); info_m_port = CFMachPortGetPort(i_port); CFRunLoopAddSource(CFRunLoopGetCurrent(), d_rls, kCFRunLoopDefaultMode); CFRunLoopAddSource(CFRunLoopGetCurrent(), s_rls, kCFRunLoopDefaultMode); CFRunLoopAddSource(CFRunLoopGetCurrent(), e_rls, kCFRunLoopDefaultMode); CFRunLoopAddSource(CFRunLoopGetCurrent(), i_rls, kCFRunLoopDefaultMode); CFRelease(d_rls); CFRelease(s_rls); CFRelease(e_rls); CFRelease(i_rls); if (debug_mode) printf("Service registered with Mach Port %d\n", m_port); #if ENABLE_UDS err = udsserver_init(); if (err) { LogMsg("Daemon start: udsserver_init failed"); return err; } err = udsserver_add_rl_source(); if (err) { LogMsg("Daemon start: udsserver_add_rl_source failed"); return err; } #endif return(err); } mDNSlocal mDNSs32 mDNSDaemonIdle(void) { // 1. Call mDNS_Execute() to let mDNSCore do what it needs to do mDNSs32 nextevent = mDNS_Execute(&mDNSStorage); mDNSs32 now = mDNSPlatformTimeNow(); // 2. Deliver any waiting browse messages to clients DNSServiceBrowser *b = DNSServiceBrowserList; while (b) { // NOTE: Need to advance b to the next element BEFORE we call DeliverInstance(), because in the // event that the client Mach queue overflows, DeliverInstance() will call AbortBlockedClient() // and that will cause the DNSServiceBrowser object's memory to be freed before it returns DNSServiceBrowser *x = b; b = b->next; if (x->results) // Try to deliver the list of results { while (x->results) { DNSServiceBrowserResult *const r = x->results; domainlabel name; domainname type, domain; DeconstructServiceName(&r->result, &name, &type, &domain); // Don't need to check result; already validated in FoundInstance() char cname[MAX_DOMAIN_LABEL+1]; // Unescaped name: up to 63 bytes plus C-string terminating NULL. char ctype[MAX_ESCAPED_DOMAIN_NAME]; char cdom [MAX_ESCAPED_DOMAIN_NAME]; ConvertDomainLabelToCString_unescaped(&name, cname); ConvertDomainNameToCString(&type, ctype); ConvertDomainNameToCString(&domain, cdom); DNSServiceDiscoveryReplyFlags flags = (r->next) ? DNSServiceDiscoverReplyFlagsMoreComing : 0; kern_return_t status = DNSServiceBrowserReply_rpc(x->ClientMachPort, r->resultType, cname, ctype, cdom, flags, 1); // If we failed to send the mach message, try again in one second if (status == MACH_SEND_TIMED_OUT) { if (nextevent - now > mDNSPlatformOneSecond) nextevent = now + mDNSPlatformOneSecond; break; } else { x->lastsuccess = now; x->results = x->results->next; freeL("DNSServiceBrowserResult", r); } } // If this client hasn't read a single message in the last 60 seconds, abort it if (now - x->lastsuccess >= 60 * mDNSPlatformOneSecond) AbortBlockedClient(x->ClientMachPort, "browse", x); } } DNSServiceResolver *l; for (l = DNSServiceResolverList; l; l=l->next) if (l->ReportTime && now - l->ReportTime >= 0) { l->ReportTime = 0; LogMsg("%5d: DNSServiceResolver(%##s) has remained active for over two minutes. " "This places considerable burden on the network.", l->ClientMachPort, l->i.name.c); } return(nextevent); } mDNSexport int main(int argc, char **argv) { int i; kern_return_t status; FILE *fp; for (i=1; ipw_uid); else setuid(-2); // User "nobody" is -2; use that value if "nobody" does not appear in the password database if (status == 0) { int numevents = 0; int RunLoopStatus = kCFRunLoopRunTimedOut; // This is the main work loop: // (1) First we give mDNSCore a chance to finish off any of its deferred work and calculate the next sleep time // (2) Then we make sure we've delivered all waiting browse messages to our clients // (3) Then we sleep for the time requested by mDNSCore, or until the next event, whichever is sooner // (4) On wakeup we first process *all* events // (5) then when no more events remain, we go back to (1) to finish off any deferred work and do it all again while (RunLoopStatus == kCFRunLoopRunTimedOut) { // 1. Before going into a blocking wait call and letting our process to go sleep, // call mDNSDaemonIdle to allow any deferred work to be completed. mDNSs32 nextevent = mDNSDaemonIdle(); #if ENABLE_UDS nextevent = udsserver_idle(nextevent); #endif // 2. Work out how long we expect to sleep before the next scheduled task mDNSs32 ticks = nextevent - mDNSPlatformTimeNow(); if (ticks < 1) ticks = 1; CFAbsoluteTime interval = (CFAbsoluteTime)ticks / (CFAbsoluteTime)mDNSPlatformOneSecond; // 3. Now do a blocking "CFRunLoopRunInMode" call so we sleep until // (a) our next wakeup time, or (b) an event occurs. // The 'true' parameter makes it return after handling any event that occurs // This gives us chance to regain control so we can call mDNS_Execute() before sleeping again verbosedebugf("main: Handled %d events; now sleeping for %d ticks", numevents, ticks); numevents = 0; RunLoopStatus = CFRunLoopRunInMode(kCFRunLoopDefaultMode, interval, true); // 4. Time to do some work? Handle all remaining events as quickly as we can, before returning to mDNSDaemonIdle() while (RunLoopStatus == kCFRunLoopRunHandledSource) { numevents++; RunLoopStatus = CFRunLoopRunInMode(kCFRunLoopDefaultMode, 0.0, true); } } LogMsg("ERROR: CFRunLoopRun Exiting."); mDNS_Close(&mDNSStorage); } destroyBootstrapService(); return(status); } // For convenience when using the "strings" command, this is the last thing in the file mDNSexport const char mDNSResponderVersionString[] = STRINGIFY(mDNSResponderVersion) " (" __DATE__ " " __TIME__ ")";