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1 /* -*- Mode: C; tab-width: 4 -*-
2 *
3 * Copyright (c) 2002-2004 Apple Computer, Inc. All rights reserved.
4 *
5 * Licensed under the Apache License, Version 2.0 (the "License");
6 * you may not use this file except in compliance with the License.
7 * You may obtain a copy of the License at
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 *
17 * Formatting notes:
18 * This code follows the "Whitesmiths style" C indentation rules. Plenty of discussion
19 * on C indentation can be found on the web, such as <http://www.kafejo.com/komp/1tbs.htm>,
20 * but for the sake of brevity here I will say just this: Curly braces are not syntactially
21 * part of an "if" statement; they are the beginning and ending markers of a compound statement;
22 * therefore common sense dictates that if they are part of a compound statement then they
23 * should be indented to the same level as everything else in that compound statement.
24 * Indenting curly braces at the same level as the "if" implies that curly braces are
25 * part of the "if", which is false. (This is as misleading as people who write "char* x,y;"
26 * thinking that variables x and y are both of type "char*" -- and anyone who doesn't
27 * understand why variable y is not of type "char*" just proves the point that poor code
28 * layout leads people to unfortunate misunderstandings about how the C language really works.)
29
30 Change History (most recent first):
31
32 $Log: NetMonitor.c,v $
33 Revision 1.94 2009/04/24 00:31:56 cheshire
34 <rdar://problem/3476350> Return negative answers when host knows authoritatively that no answer exists
35 Added code to display NSEC records
36
37 Revision 1.93 2009/01/13 05:31:34 mkrochma
38 <rdar://problem/6491367> Replace bzero, bcopy with mDNSPlatformMemZero, mDNSPlatformMemCopy, memset, memcpy
39
40 Revision 1.92 2009/01/11 03:20:06 mkrochma
41 <rdar://problem/5797526> Fixes from Igor Seleznev to get mdnsd working on Solaris
42
43 Revision 1.91 2008/11/13 22:08:07 cheshire
44 Show additional records in Query packets
45
46 Revision 1.90 2008/09/05 22:20:26 cheshire
47 <rdar://problem/3988320> Should use randomized source ports and transaction IDs to avoid DNS cache poisoning
48 Add "UDPSocket *src" parameter in mDNSPlatformSendUDP call
49
50 Revision 1.89 2007/05/17 19:12:42 cheshire
51 Tidy up code layout
52
53 Revision 1.88 2007/04/22 20:16:25 cheshire
54 Fix compiler errors (const parameter declarations)
55
56 Revision 1.87 2007/04/16 20:49:39 cheshire
57 Fix compile errors for mDNSPosix build
58
59 Revision 1.86 2007/03/22 18:31:48 cheshire
60 Put dst parameter first in mDNSPlatformStrCopy/mDNSPlatformMemCopy, like conventional Posix strcpy/memcpy
61
62 Revision 1.85 2007/02/28 01:51:22 cheshire
63 Added comment about reverse-order IP address
64
65 Revision 1.84 2007/01/05 08:30:52 cheshire
66 Trim excessive "$Log" checkin history from before 2006
67 (checkin history still available via "cvs log ..." of course)
68
69 Revision 1.83 2006/11/18 05:01:32 cheshire
70 Preliminary support for unifying the uDNS and mDNS code,
71 including caching of uDNS answers
72
73 Revision 1.82 2006/08/14 23:24:46 cheshire
74 Re-licensed mDNSResponder daemon source code under Apache License, Version 2.0
75
76 Revision 1.81 2006/07/06 00:01:44 cheshire
77 <rdar://problem/4472014> Add Private DNS client functionality to mDNSResponder
78 Update mDNSSendDNSMessage() to use uDNS_TCPSocket type instead of "int"
79
80 Revision 1.80 2006/06/12 18:22:42 cheshire
81 <rdar://problem/4580067> mDNSResponder building warnings under Red Hat 64-bit (LP64) Linux
82
83 Revision 1.79 2006/04/26 20:48:33 cheshire
84 Make final count of unique source addresses show IPv4 and IPv6 counts separately
85
86 Revision 1.78 2006/04/25 00:42:24 cheshire
87 Add ability to specify a single interface index to capture on,
88 e.g. typically "-i 4" for Ethernet and "-i 5" for AirPort
89
90 Revision 1.77 2006/03/02 21:50:45 cheshire
91 Removed strange backslash at the end of a line
92
93 Revision 1.76 2006/02/23 23:38:43 cheshire
94 <rdar://problem/4427969> On FreeBSD 4 "arpa/inet.h" requires "netinet/in.h" be included first
95
96 Revision 1.75 2006/01/05 22:33:58 cheshire
97 Use IFNAMSIZ (more portable) instead of IF_NAMESIZE
98
99 */
100
101 //*************************************************************************************************************
102 // Incorporate mDNS.c functionality
103
104 // We want to use much of the functionality provided by "mDNS.c",
105 // except we'll steal the packets that would be sent to normal mDNSCoreReceive() routine
106 #define mDNSCoreReceive __NOT__mDNSCoreReceive__NOT__
107 #include "mDNS.c"
108 #undef mDNSCoreReceive
109
110 //*************************************************************************************************************
111 // Headers
112
113 #include <stdio.h> // For printf()
114 #include <stdlib.h> // For malloc()
115 #include <string.h> // For strrchr(), strcmp()
116 #include <time.h> // For "struct tm" etc.
117 #include <signal.h> // For SIGINT, SIGTERM
118 #include <netdb.h> // For gethostbyname()
119 #include <sys/socket.h> // For AF_INET, AF_INET6, etc.
120 #include <net/if.h> // For IF_NAMESIZE
121 #include <netinet/in.h> // For INADDR_NONE
122 #include <arpa/inet.h> // For inet_addr()
123
124 #include "mDNSPosix.h" // Defines the specific types needed to run mDNS on this platform
125 #include "ExampleClientApp.h"
126
127 //*************************************************************************************************************
128 // Types and structures
129
130 enum
131 {
132 // Primitive operations
133 OP_probe = 0,
134 OP_goodbye = 1,
135
136 // These are meta-categories;
137 // Query and Answer operations are actually subdivided into two classes:
138 // Browse query/answer and
139 // Resolve query/answer
140 OP_query = 2,
141 OP_answer = 3,
142
143 // The "Browse" variants of query/answer
144 OP_browsegroup = 2,
145 OP_browseq = 2,
146 OP_browsea = 3,
147
148 // The "Resolve" variants of query/answer
149 OP_resolvegroup = 4,
150 OP_resolveq = 4,
151 OP_resolvea = 5,
152
153 OP_NumTypes = 6
154 };
155
156 typedef struct ActivityStat_struct ActivityStat;
157 struct ActivityStat_struct
158 {
159 ActivityStat *next;
160 domainname srvtype;
161 int printed;
162 int totalops;
163 int stat[OP_NumTypes];
164 };
165
166 typedef struct FilterList_struct FilterList;
167 struct FilterList_struct
168 {
169 FilterList *next;
170 mDNSAddr FilterAddr;
171 };
172
173 //*************************************************************************************************************
174 // Constants
175
176 #define kReportTopServices 15
177 #define kReportTopHosts 15
178
179 //*************************************************************************************************************
180 // Globals
181
182 static mDNS mDNSStorage; // mDNS core uses this to store its globals
183 static mDNS_PlatformSupport PlatformStorage; // Stores this platform's globals
184 mDNSexport const char ProgramName[] = "mDNSNetMonitor";
185
186 struct timeval tv_start, tv_end, tv_interval;
187 static int FilterInterface = 0;
188 static FilterList *Filters;
189 #define ExactlyOneFilter (Filters && !Filters->next)
190
191 static int NumPktQ, NumPktL, NumPktR, NumPktB; // Query/Legacy/Response/Bad
192 static int NumProbes, NumGoodbyes, NumQuestions, NumLegacy, NumAnswers, NumAdditionals;
193
194 static ActivityStat *stats;
195
196 #define OPBanner "Total Ops Probe Goodbye BrowseQ BrowseA ResolveQ ResolveA"
197
198 //*************************************************************************************************************
199 // Utilities
200
201 // Special version of printf that knows how to print IP addresses, DNS-format name strings, etc.
202 mDNSlocal mDNSu32 mprintf(const char *format, ...) IS_A_PRINTF_STYLE_FUNCTION(1,2);
203 mDNSlocal mDNSu32 mprintf(const char *format, ...)
204 {
205 mDNSu32 length;
206 unsigned char buffer[512];
207 va_list ptr;
208 va_start(ptr,format);
209 length = mDNS_vsnprintf((char *)buffer, sizeof(buffer), format, ptr);
210 va_end(ptr);
211 printf("%s", buffer);
212 return(length);
213 }
214
215 //*************************************************************************************************************
216 // Host Address List
217 //
218 // Would benefit from a hash
219
220 typedef enum
221 {
222 HostPkt_Q = 0, // Query
223 HostPkt_L = 1, // Legacy Query
224 HostPkt_R = 2, // Response
225 HostPkt_B = 3, // Bad
226 HostPkt_NumTypes = 4
227 } HostPkt_Type;
228
229 typedef struct
230 {
231 mDNSAddr addr;
232 unsigned long pkts[HostPkt_NumTypes];
233 unsigned long totalops;
234 unsigned long stat[OP_NumTypes];
235 domainname hostname;
236 domainname revname;
237 UTF8str255 HIHardware;
238 UTF8str255 HISoftware;
239 mDNSu32 NumQueries;
240 mDNSs32 LastQuery;
241 } HostEntry;
242
243 #define HostEntryTotalPackets(H) ((H)->pkts[HostPkt_Q] + (H)->pkts[HostPkt_L] + (H)->pkts[HostPkt_R] + (H)->pkts[HostPkt_B])
244
245 typedef struct
246 {
247 long num;
248 long max;
249 HostEntry *hosts;
250 } HostList;
251
252 static HostList IPv4HostList = { 0, 0, 0 };
253 static HostList IPv6HostList = { 0, 0, 0 };
254
255 mDNSlocal HostEntry *FindHost(const mDNSAddr *addr, HostList *list)
256 {
257 long i;
258
259 for (i = 0; i < list->num; i++)
260 {
261 HostEntry *entry = list->hosts + i;
262 if (mDNSSameAddress(addr, &entry->addr))
263 return entry;
264 }
265
266 return NULL;
267 }
268
269 mDNSlocal HostEntry *AddHost(const mDNSAddr *addr, HostList *list)
270 {
271 int i;
272 HostEntry *entry;
273 if (list->num >= list->max)
274 {
275 long newMax = list->max + 64;
276 HostEntry *newHosts = realloc(list->hosts, newMax * sizeof(HostEntry));
277 if (newHosts == NULL)
278 return NULL;
279 list->max = newMax;
280 list->hosts = newHosts;
281 }
282
283 entry = list->hosts + list->num++;
284
285 entry->addr = *addr;
286 for (i=0; i<HostPkt_NumTypes; i++) entry->pkts[i] = 0;
287 entry->totalops = 0;
288 for (i=0; i<OP_NumTypes; i++) entry->stat[i] = 0;
289 entry->hostname.c[0] = 0;
290 entry->revname.c[0] = 0;
291 entry->HIHardware.c[0] = 0;
292 entry->HISoftware.c[0] = 0;
293 entry->NumQueries = 0;
294
295 if (entry->addr.type == mDNSAddrType_IPv4)
296 {
297 mDNSv4Addr ip = entry->addr.ip.v4;
298 char buffer[32];
299 // Note: This is reverse order compared to a normal dotted-decimal IP address, so we can't use our customary "%.4a" format code
300 mDNS_snprintf(buffer, sizeof(buffer), "%d.%d.%d.%d.in-addr.arpa.", ip.b[3], ip.b[2], ip.b[1], ip.b[0]);
301 MakeDomainNameFromDNSNameString(&entry->revname, buffer);
302 }
303
304 return(entry);
305 }
306
307 mDNSlocal HostEntry *GotPacketFromHost(const mDNSAddr *addr, HostPkt_Type t, mDNSOpaque16 id)
308 {
309 if (ExactlyOneFilter) return(NULL);
310 else
311 {
312 HostList *list = (addr->type == mDNSAddrType_IPv4) ? &IPv4HostList : &IPv6HostList;
313 HostEntry *entry = FindHost(addr, list);
314 if (!entry) entry = AddHost(addr, list);
315 if (!entry) return(NULL);
316 // Don't count our own interrogation packets
317 if (id.NotAnInteger != 0xFFFF) entry->pkts[t]++;
318 return(entry);
319 }
320 }
321
322 mDNSlocal void RecordHostInfo(HostEntry *entry, const ResourceRecord *const pktrr)
323 {
324 if (!entry->hostname.c[0])
325 {
326 if (pktrr->rrtype == kDNSType_A || pktrr->rrtype == kDNSType_AAAA)
327 {
328 // Should really check that the rdata in the address record matches the source address of this packet
329 entry->NumQueries = 0;
330 AssignDomainName(&entry->hostname, pktrr->name);
331 }
332
333 if (pktrr->rrtype == kDNSType_PTR)
334 if (SameDomainName(&entry->revname, pktrr->name))
335 {
336 entry->NumQueries = 0;
337 AssignDomainName(&entry->hostname, &pktrr->rdata->u.name);
338 }
339 }
340 else if (pktrr->rrtype == kDNSType_HINFO)
341 {
342 RDataBody *rd = &pktrr->rdata->u;
343 mDNSu8 *rdend = (mDNSu8 *)rd + pktrr->rdlength;
344 mDNSu8 *hw = rd->txt.c;
345 mDNSu8 *sw = hw + 1 + (mDNSu32)hw[0];
346 if (sw + 1 + sw[0] <= rdend)
347 {
348 AssignDomainName(&entry->hostname, pktrr->name);
349 mDNSPlatformMemCopy(entry->HIHardware.c, hw, 1 + (mDNSu32)hw[0]);
350 mDNSPlatformMemCopy(entry->HISoftware.c, sw, 1 + (mDNSu32)sw[0]);
351 }
352 }
353 }
354
355 mDNSlocal void SendUnicastQuery(mDNS *const m, HostEntry *entry, domainname *name, mDNSu16 rrtype, mDNSInterfaceID InterfaceID)
356 {
357 const mDNSOpaque16 id = { { 0xFF, 0xFF } };
358 DNSMessage query;
359 mDNSu8 *qptr = query.data;
360 const mDNSu8 *const limit = query.data + sizeof(query.data);
361 const mDNSAddr *target = &entry->addr;
362 InitializeDNSMessage(&query.h, id, QueryFlags);
363 qptr = putQuestion(&query, qptr, limit, name, rrtype, kDNSClass_IN);
364 entry->LastQuery = m->timenow;
365 entry->NumQueries++;
366
367 // Note: When there are multiple mDNSResponder agents running on a single machine
368 // (e.g. Apple mDNSResponder plus a SliMP3 server with embedded mDNSResponder)
369 // it is possible that unicast queries may not go to the primary system responder.
370 // We try the first query using unicast, but if that doesn't work we try again via multicast.
371 if (entry->NumQueries > 2)
372 {
373 target = &AllDNSLinkGroup_v4;
374 }
375 else
376 {
377 //mprintf("%#a Q\n", target);
378 InterfaceID = mDNSInterface_Any; // Send query from our unicast reply socket
379 }
380
381 mDNSSendDNSMessage(&mDNSStorage, &query, qptr, InterfaceID, mDNSNULL, target, MulticastDNSPort, mDNSNULL, mDNSNULL);
382 }
383
384 mDNSlocal void AnalyseHost(mDNS *const m, HostEntry *entry, const mDNSInterfaceID InterfaceID)
385 {
386 // If we've done four queries without answer, give up
387 if (entry->NumQueries >= 4) return;
388
389 // If we've done a query in the last second, give the host a chance to reply before trying again
390 if (entry->NumQueries && m->timenow - entry->LastQuery < mDNSPlatformOneSecond) return;
391
392 // If we don't know the host name, try to find that first
393 if (!entry->hostname.c[0])
394 {
395 if (entry->revname.c[0])
396 {
397 SendUnicastQuery(m, entry, &entry->revname, kDNSType_PTR, InterfaceID);
398 //mprintf("%##s PTR %d\n", entry->revname.c, entry->NumQueries);
399 }
400 }
401 // If we have the host name but no HINFO, now ask for that
402 else if (!entry->HIHardware.c[0])
403 {
404 SendUnicastQuery(m, entry, &entry->hostname, kDNSType_HINFO, InterfaceID);
405 //mprintf("%##s HINFO %d\n", entry->hostname.c, entry->NumQueries);
406 }
407 }
408
409 mDNSlocal int CompareHosts(const void *p1, const void *p2)
410 {
411 return (int)(HostEntryTotalPackets((HostEntry *)p2) - HostEntryTotalPackets((HostEntry *)p1));
412 }
413
414 mDNSlocal void ShowSortedHostList(HostList *list, int max)
415 {
416 HostEntry *e, *end = &list->hosts[(max < list->num) ? max : list->num];
417 qsort(list->hosts, list->num, sizeof(HostEntry), CompareHosts);
418 if (list->num) mprintf("\n%-25s%s%s\n", "Source Address", OPBanner, " Pkts Query LegacyQ Response");
419 for (e = &list->hosts[0]; e < end; e++)
420 {
421 int len = mprintf("%#-25a", &e->addr);
422 if (len > 25) mprintf("\n%25s", "");
423 mprintf("%8lu %8lu %8lu %8lu %8lu %8lu %8lu", e->totalops,
424 e->stat[OP_probe], e->stat[OP_goodbye],
425 e->stat[OP_browseq], e->stat[OP_browsea],
426 e->stat[OP_resolveq], e->stat[OP_resolvea]);
427 mprintf(" %8lu %8lu %8lu %8lu",
428 HostEntryTotalPackets(e), e->pkts[HostPkt_Q], e->pkts[HostPkt_L], e->pkts[HostPkt_R]);
429 if (e->pkts[HostPkt_B]) mprintf("Bad: %8lu", e->pkts[HostPkt_B]);
430 mprintf("\n");
431 if (!e->HISoftware.c[0] && e->NumQueries > 2)
432 mDNSPlatformMemCopy(&e->HISoftware, "\x27*** Unknown (Jaguar, Windows, etc.) ***", 0x28);
433 if (e->hostname.c[0] || e->HIHardware.c[0] || e->HISoftware.c[0])
434 mprintf("%##-45s %#-14s %#s\n", e->hostname.c, e->HIHardware.c, e->HISoftware.c);
435 }
436 }
437
438 //*************************************************************************************************************
439 // Receive and process packets
440
441 mDNSexport mDNSBool ExtractServiceType(const domainname *const fqdn, domainname *const srvtype)
442 {
443 int i, len;
444 const mDNSu8 *src = fqdn->c;
445 mDNSu8 *dst = srvtype->c;
446
447 len = *src;
448 if (len == 0 || len >= 0x40) return(mDNSfalse);
449 if (src[1] != '_') src += 1 + len;
450
451 len = *src;
452 if (len == 0 || len >= 0x40 || src[1] != '_') return(mDNSfalse);
453 for (i=0; i<=len; i++) *dst++ = *src++;
454
455 len = *src;
456 if (len == 0 || len >= 0x40 || src[1] != '_') return(mDNSfalse);
457 for (i=0; i<=len; i++) *dst++ = *src++;
458
459 *dst++ = 0; // Put the null root label on the end of the service type
460
461 return(mDNStrue);
462 }
463
464 mDNSlocal void recordstat(HostEntry *entry, const domainname *fqdn, int op, mDNSu16 rrtype)
465 {
466 ActivityStat **s = &stats;
467 domainname srvtype;
468
469 if (op != OP_probe)
470 {
471 if (rrtype == kDNSType_SRV || rrtype == kDNSType_TXT) op = op - OP_browsegroup + OP_resolvegroup;
472 else if (rrtype != kDNSType_PTR) return;
473 }
474
475 if (!ExtractServiceType(fqdn, &srvtype)) return;
476
477 while (*s && !SameDomainName(&(*s)->srvtype, &srvtype)) s = &(*s)->next;
478 if (!*s)
479 {
480 int i;
481 *s = malloc(sizeof(ActivityStat));
482 if (!*s) exit(-1);
483 (*s)->next = NULL;
484 (*s)->srvtype = srvtype;
485 (*s)->printed = 0;
486 (*s)->totalops = 0;
487 for (i=0; i<OP_NumTypes; i++) (*s)->stat[i] = 0;
488 }
489
490 (*s)->totalops++;
491 (*s)->stat[op]++;
492 if (entry)
493 {
494 entry->totalops++;
495 entry->stat[op]++;
496 }
497 }
498
499 mDNSlocal void printstats(int max)
500 {
501 int i;
502 if (!stats) return;
503 for (i=0; i<max; i++)
504 {
505 int max = 0;
506 ActivityStat *s, *m = NULL;
507 for (s = stats; s; s=s->next)
508 if (!s->printed && max < s->totalops)
509 { m = s; max = s->totalops; }
510 if (!m) return;
511 m->printed = mDNStrue;
512 if (i==0) mprintf("%-25s%s\n", "Service Type", OPBanner);
513 mprintf("%##-25s%8d %8d %8d %8d %8d %8d %8d\n", m->srvtype.c, m->totalops, m->stat[OP_probe],
514 m->stat[OP_goodbye], m->stat[OP_browseq], m->stat[OP_browsea], m->stat[OP_resolveq], m->stat[OP_resolvea]);
515 }
516 }
517
518 mDNSlocal const mDNSu8 *FindUpdate(mDNS *const m, const DNSMessage *const query, const mDNSu8 *ptr, const mDNSu8 *const end,
519 DNSQuestion *q, LargeCacheRecord *pkt)
520 {
521 int i;
522 for (i = 0; i < query->h.numAuthorities; i++)
523 {
524 const mDNSu8 *p2 = ptr;
525 ptr = GetLargeResourceRecord(m, query, ptr, end, q->InterfaceID, kDNSRecordTypePacketAuth, pkt);
526 if (!ptr) break;
527 if (ResourceRecordAnswersQuestion(&pkt->r.resrec, q)) return(p2);
528 }
529 return(mDNSNULL);
530 }
531
532 mDNSlocal void DisplayPacketHeader(mDNS *const m, const DNSMessage *const msg, const mDNSu8 *const end, const mDNSAddr *srcaddr, mDNSIPPort srcport, const mDNSAddr *dstaddr, const mDNSInterfaceID InterfaceID)
533 {
534 const char *const ptype = (msg->h.flags.b[0] & kDNSFlag0_QR_Response) ? "-R- " :
535 (srcport.NotAnInteger == MulticastDNSPort.NotAnInteger) ? "-Q- " : "-LQ-";
536
537 struct timeval tv;
538 struct tm tm;
539 const mDNSu32 index = mDNSPlatformInterfaceIndexfromInterfaceID(m, InterfaceID);
540 char if_name[IFNAMSIZ]; // Older Linux distributions don't define IF_NAMESIZE
541 if_indextoname(index, if_name);
542 gettimeofday(&tv, NULL);
543 localtime_r((time_t*)&tv.tv_sec, &tm);
544 mprintf("\n%d:%02d:%02d.%06d Interface %d/%s\n", tm.tm_hour, tm.tm_min, tm.tm_sec, tv.tv_usec, index, if_name);
545
546 mprintf("%#-16a %s Q:%3d Ans:%3d Auth:%3d Add:%3d Size:%5d bytes",
547 srcaddr, ptype, msg->h.numQuestions, msg->h.numAnswers, msg->h.numAuthorities, msg->h.numAdditionals, end - (mDNSu8 *)msg);
548
549 if (msg->h.id.NotAnInteger) mprintf(" ID:%u", mDNSVal16(msg->h.id));
550
551 if (!mDNSAddrIsDNSMulticast(dstaddr)) mprintf(" To: %#a", dstaddr);
552
553 if (msg->h.flags.b[0] & kDNSFlag0_TC)
554 {
555 if (msg->h.flags.b[0] & kDNSFlag0_QR_Response) mprintf(" Truncated");
556 else mprintf(" Truncated (KA list continues in next packet)");
557 }
558 mprintf("\n");
559 }
560
561 mDNSlocal void DisplayResourceRecord(const mDNSAddr *const srcaddr, const char *const op, const ResourceRecord *const pktrr)
562 {
563 static const char hexchars[16] = "0123456789ABCDEF";
564 #define MaxWidth 132
565 char buffer[MaxWidth+8];
566 char *p = buffer;
567
568 RDataBody *rd = &pktrr->rdata->u;
569 mDNSu8 *rdend = (mDNSu8 *)rd + pktrr->rdlength;
570 int n = mprintf("%#-16a %-5s %-5s%5lu %##s -> ", srcaddr, op, DNSTypeName(pktrr->rrtype), pktrr->rroriginalttl, pktrr->name->c);
571
572 switch(pktrr->rrtype)
573 {
574 case kDNSType_A: n += mprintf("%.4a", &rd->ipv4); break;
575 case kDNSType_PTR: n += mprintf("%##.*s", MaxWidth - n, rd->name.c); break;
576 case kDNSType_HINFO:// same as kDNSType_TXT below
577 case kDNSType_TXT: {
578 mDNSu8 *t = rd->txt.c;
579 while (t < rdend && t[0] && p < buffer+MaxWidth)
580 {
581 int i;
582 for (i=1; i<=t[0] && p < buffer+MaxWidth; i++)
583 {
584 if (t[i] == '\\') *p++ = '\\';
585 if (t[i] >= ' ') *p++ = t[i];
586 else
587 {
588 *p++ = '\\';
589 *p++ = '0';
590 *p++ = 'x';
591 *p++ = hexchars[t[i] >> 4];
592 *p++ = hexchars[t[i] & 0xF];
593 }
594 }
595 t += 1+t[0];
596 if (t < rdend && t[0]) { *p++ = '\\'; *p++ = ' '; }
597 }
598 *p++ = 0;
599 n += mprintf("%.*s", MaxWidth - n, buffer);
600 } break;
601 case kDNSType_AAAA: n += mprintf("%.16a", &rd->ipv6); break;
602 case kDNSType_SRV: n += mprintf("%##s:%d", rd->srv.target.c, mDNSVal16(rd->srv.port)); break;
603 case kDNSType_NSEC: {
604 int i;
605 for (i=0; i<255; i++)
606 if (rd->nsec.bitmap[i>>3] & (128 >> (i&7)))
607 n += mprintf("%s ", DNSTypeName(i));
608 } break;
609 default: {
610 mDNSu8 *s = rd->data;
611 while (s < rdend && p < buffer+MaxWidth)
612 {
613 if (*s == '\\') *p++ = '\\';
614 if (*s >= ' ') *p++ = *s;
615 else
616 {
617 *p++ = '\\';
618 *p++ = '0';
619 *p++ = 'x';
620 *p++ = hexchars[*s >> 4];
621 *p++ = hexchars[*s & 0xF];
622 }
623 s++;
624 }
625 *p++ = 0;
626 n += mprintf("%.*s", MaxWidth - n, buffer);
627 } break;
628 }
629
630 mprintf("\n");
631 }
632
633 mDNSlocal void HexDump(const mDNSu8 *ptr, const mDNSu8 *const end)
634 {
635 while (ptr < end)
636 {
637 int i;
638 for (i=0; i<16; i++)
639 if (&ptr[i] < end) mprintf("%02X ", ptr[i]);
640 else mprintf(" ");
641 for (i=0; i<16; i++)
642 if (&ptr[i] < end) mprintf("%c", ptr[i] <= ' ' || ptr[i] >= 126 ? '.' : ptr[i]);
643 ptr += 16;
644 mprintf("\n");
645 }
646 }
647
648 mDNSlocal void DisplayError(const mDNSAddr *srcaddr, const mDNSu8 *ptr, const mDNSu8 *const end, char *msg)
649 {
650 mprintf("%#-16a **** ERROR: FAILED TO READ %s **** \n", srcaddr, msg);
651 HexDump(ptr, end);
652 }
653
654 mDNSlocal void DisplayQuery(mDNS *const m, const DNSMessage *const msg, const mDNSu8 *const end,
655 const mDNSAddr *srcaddr, mDNSIPPort srcport, const mDNSAddr *dstaddr, const mDNSInterfaceID InterfaceID)
656 {
657 int i;
658 const mDNSu8 *ptr = msg->data;
659 const mDNSu8 *auth = LocateAuthorities(msg, end);
660 mDNSBool MQ = (srcport.NotAnInteger == MulticastDNSPort.NotAnInteger);
661 HostEntry *entry = GotPacketFromHost(srcaddr, MQ ? HostPkt_Q : HostPkt_L, msg->h.id);
662 LargeCacheRecord pkt;
663
664 DisplayPacketHeader(m, msg, end, srcaddr, srcport, dstaddr, InterfaceID);
665 if (msg->h.id.NotAnInteger != 0xFFFF)
666 {
667 if (MQ) NumPktQ++; else NumPktL++;
668 }
669
670 for (i=0; i<msg->h.numQuestions; i++)
671 {
672 DNSQuestion q;
673 mDNSu8 *p2 = (mDNSu8 *)getQuestion(msg, ptr, end, InterfaceID, &q);
674 mDNSu16 ucbit = q.qclass & kDNSQClass_UnicastResponse;
675 q.qclass &= ~kDNSQClass_UnicastResponse;
676 if (!p2) { DisplayError(srcaddr, ptr, end, "QUESTION"); return; }
677 ptr = p2;
678 p2 = (mDNSu8 *)FindUpdate(m, msg, auth, end, &q, &pkt);
679 if (p2)
680 {
681 NumProbes++;
682 DisplayResourceRecord(srcaddr, ucbit ? "(PU)" : "(PM)", &pkt.r.resrec);
683 recordstat(entry, &q.qname, OP_probe, q.qtype);
684 p2 = (mDNSu8 *)skipDomainName(msg, p2, end);
685 // Having displayed this update record, clear type and class so we don't display the same one again.
686 p2[0] = p2[1] = p2[2] = p2[3] = 0;
687 }
688 else
689 {
690 const char *ptype = ucbit ? "(QU)" : "(QM)";
691 if (srcport.NotAnInteger == MulticastDNSPort.NotAnInteger) NumQuestions++;
692 else { NumLegacy++; ptype = "(LQ)"; }
693 mprintf("%#-16a %-5s %-5s %##s\n", srcaddr, ptype, DNSTypeName(q.qtype), q.qname.c);
694 if (msg->h.id.NotAnInteger != 0xFFFF) recordstat(entry, &q.qname, OP_query, q.qtype);
695 }
696 }
697
698 for (i=0; i<msg->h.numAnswers; i++)
699 {
700 const mDNSu8 *ep = ptr;
701 ptr = GetLargeResourceRecord(m, msg, ptr, end, InterfaceID, kDNSRecordTypePacketAns, &pkt);
702 if (!ptr) { DisplayError(srcaddr, ep, end, "KNOWN ANSWER"); return; }
703 DisplayResourceRecord(srcaddr, "(KA)", &pkt.r.resrec);
704
705 // In the case of queries with long multi-packet KA lists, we count each subsequent KA packet
706 // the same as a single query, to more accurately reflect the burden on the network
707 // (A query with a six-packet KA list is *at least* six times the burden on the network as a single-packet query.)
708 if (msg->h.numQuestions == 0 && i == 0)
709 recordstat(entry, pkt.r.resrec.name, OP_query, pkt.r.resrec.rrtype);
710 }
711
712 for (i=0; i<msg->h.numAuthorities; i++)
713 {
714 const mDNSu8 *ep = ptr;
715 ptr = skipResourceRecord(msg, ptr, end);
716 if (!ptr) { DisplayError(srcaddr, ep, end, "AUTHORITY"); return; }
717 }
718
719 for (i=0; i<msg->h.numAdditionals; i++)
720 {
721 const mDNSu8 *ep = ptr;
722 ptr = GetLargeResourceRecord(m, msg, ptr, end, InterfaceID, kDNSRecordTypePacketAns, &pkt);
723 if (!ptr) { DisplayError(srcaddr, ep, end, "ADDITIONAL"); return; }
724 DisplayResourceRecord(srcaddr, " ", &pkt.r.resrec);
725 }
726
727 if (entry) AnalyseHost(m, entry, InterfaceID);
728 }
729
730 mDNSlocal void DisplayResponse(mDNS *const m, const DNSMessage *const msg, const mDNSu8 *end,
731 const mDNSAddr *srcaddr, mDNSIPPort srcport, const mDNSAddr *dstaddr, const mDNSInterfaceID InterfaceID)
732 {
733 int i;
734 const mDNSu8 *ptr = msg->data;
735 HostEntry *entry = GotPacketFromHost(srcaddr, HostPkt_R, msg->h.id);
736 LargeCacheRecord pkt;
737
738 DisplayPacketHeader(m, msg, end, srcaddr, srcport, dstaddr, InterfaceID);
739 if (msg->h.id.NotAnInteger != 0xFFFF) NumPktR++;
740
741 for (i=0; i<msg->h.numQuestions; i++)
742 {
743 DNSQuestion q;
744 const mDNSu8 *ep = ptr;
745 ptr = getQuestion(msg, ptr, end, InterfaceID, &q);
746 if (!ptr) { DisplayError(srcaddr, ep, end, "QUESTION"); return; }
747 if (mDNSAddrIsDNSMulticast(dstaddr))
748 mprintf("%#-16a (?) **** ERROR: SHOULD NOT HAVE Q IN mDNS RESPONSE **** %-5s %##s\n", srcaddr, DNSTypeName(q.qtype), q.qname.c);
749 else
750 mprintf("%#-16a (Q) %-5s %##s\n", srcaddr, DNSTypeName(q.qtype), q.qname.c);
751 }
752
753 for (i=0; i<msg->h.numAnswers; i++)
754 {
755 const mDNSu8 *ep = ptr;
756 ptr = GetLargeResourceRecord(m, msg, ptr, end, InterfaceID, kDNSRecordTypePacketAns, &pkt);
757 if (!ptr) { DisplayError(srcaddr, ep, end, "ANSWER"); return; }
758 if (pkt.r.resrec.rroriginalttl)
759 {
760 NumAnswers++;
761 DisplayResourceRecord(srcaddr, (pkt.r.resrec.RecordType & kDNSRecordTypePacketUniqueMask) ? "(AN)" : "(AN+)", &pkt.r.resrec);
762 if (msg->h.id.NotAnInteger != 0xFFFF) recordstat(entry, pkt.r.resrec.name, OP_answer, pkt.r.resrec.rrtype);
763 if (entry) RecordHostInfo(entry, &pkt.r.resrec);
764 }
765 else
766 {
767 NumGoodbyes++;
768 DisplayResourceRecord(srcaddr, "(DE)", &pkt.r.resrec);
769 recordstat(entry, pkt.r.resrec.name, OP_goodbye, pkt.r.resrec.rrtype);
770 }
771 }
772
773 for (i=0; i<msg->h.numAuthorities; i++)
774 {
775 const mDNSu8 *ep = ptr;
776 ptr = GetLargeResourceRecord(m, msg, ptr, end, InterfaceID, kDNSRecordTypePacketAuth, &pkt);
777 if (!ptr) { DisplayError(srcaddr, ep, end, "AUTHORITY"); return; }
778 mprintf("%#-16a (?) **** ERROR: SHOULD NOT HAVE AUTHORITY IN mDNS RESPONSE **** %-5s %##s\n",
779 srcaddr, DNSTypeName(pkt.r.resrec.rrtype), pkt.r.resrec.name->c);
780 }
781
782 for (i=0; i<msg->h.numAdditionals; i++)
783 {
784 const mDNSu8 *ep = ptr;
785 ptr = GetLargeResourceRecord(m, msg, ptr, end, InterfaceID, kDNSRecordTypePacketAdd, &pkt);
786 if (!ptr) { DisplayError(srcaddr, ep, end, "ADDITIONAL"); return; }
787 NumAdditionals++;
788 DisplayResourceRecord(srcaddr, (pkt.r.resrec.RecordType & kDNSRecordTypePacketUniqueMask) ? "(AD)" : "(AD+)", &pkt.r.resrec);
789 if (entry) RecordHostInfo(entry, &pkt.r.resrec);
790 }
791
792 if (entry) AnalyseHost(m, entry, InterfaceID);
793 }
794
795 mDNSlocal void ProcessUnicastResponse(mDNS *const m, const DNSMessage *const msg, const mDNSu8 *end, const mDNSAddr *srcaddr, const mDNSInterfaceID InterfaceID)
796 {
797 int i;
798 const mDNSu8 *ptr = LocateAnswers(msg, end);
799 HostEntry *entry = GotPacketFromHost(srcaddr, HostPkt_R, msg->h.id);
800 //mprintf("%#a R\n", srcaddr);
801
802 for (i=0; i<msg->h.numAnswers + msg->h.numAuthorities + msg->h.numAdditionals; i++)
803 {
804 LargeCacheRecord pkt;
805 ptr = GetLargeResourceRecord(m, msg, ptr, end, InterfaceID, kDNSRecordTypePacketAns, &pkt);
806 if (pkt.r.resrec.rroriginalttl && entry) RecordHostInfo(entry, &pkt.r.resrec);
807 }
808 }
809
810 mDNSlocal mDNSBool AddressMatchesFilterList(const mDNSAddr *srcaddr)
811 {
812 FilterList *f;
813 if (!Filters) return(srcaddr->type == mDNSAddrType_IPv4);
814 for (f=Filters; f; f=f->next) if (mDNSSameAddress(srcaddr, &f->FilterAddr)) return(mDNStrue);
815 return(mDNSfalse);
816 }
817
818 mDNSexport void mDNSCoreReceive(mDNS *const m, DNSMessage *const msg, const mDNSu8 *const end,
819 const mDNSAddr *srcaddr, mDNSIPPort srcport, const mDNSAddr *dstaddr, mDNSIPPort dstport, const mDNSInterfaceID InterfaceID)
820 {
821 const mDNSu8 StdQ = kDNSFlag0_QR_Query | kDNSFlag0_OP_StdQuery;
822 const mDNSu8 StdR = kDNSFlag0_QR_Response | kDNSFlag0_OP_StdQuery;
823 const mDNSu8 QR_OP = (mDNSu8)(msg->h.flags.b[0] & kDNSFlag0_QROP_Mask);
824 mDNSu8 *ptr = (mDNSu8 *)&msg->h.numQuestions;
825 int goodinterface = (FilterInterface == 0);
826
827 (void)dstaddr; // Unused
828 (void)dstport; // Unused
829
830 // Read the integer parts which are in IETF byte-order (MSB first, LSB second)
831 msg->h.numQuestions = (mDNSu16)((mDNSu16)ptr[0] << 8 | ptr[1]);
832 msg->h.numAnswers = (mDNSu16)((mDNSu16)ptr[2] << 8 | ptr[3]);
833 msg->h.numAuthorities = (mDNSu16)((mDNSu16)ptr[4] << 8 | ptr[5]);
834 msg->h.numAdditionals = (mDNSu16)((mDNSu16)ptr[6] << 8 | ptr[7]);
835
836 // For now we're only interested in monitoring IPv4 traffic.
837 // All IPv6 packets should just be duplicates of the v4 packets.
838 if (!goodinterface) goodinterface = (FilterInterface == (int)mDNSPlatformInterfaceIndexfromInterfaceID(m, InterfaceID));
839 if (goodinterface && AddressMatchesFilterList(srcaddr))
840 {
841 mDNS_Lock(m);
842 if (!mDNSAddrIsDNSMulticast(dstaddr))
843 {
844 if (QR_OP == StdQ) mprintf("Unicast query from %#a\n", srcaddr);
845 else if (QR_OP == StdR) ProcessUnicastResponse(m, msg, end, srcaddr, InterfaceID);
846 }
847 else
848 {
849 if (QR_OP == StdQ) DisplayQuery (m, msg, end, srcaddr, srcport, dstaddr, InterfaceID);
850 else if (QR_OP == StdR) DisplayResponse (m, msg, end, srcaddr, srcport, dstaddr, InterfaceID);
851 else
852 {
853 debugf("Unknown DNS packet type %02X%02X (ignored)", msg->h.flags.b[0], msg->h.flags.b[1]);
854 GotPacketFromHost(srcaddr, HostPkt_B, msg->h.id);
855 NumPktB++;
856 }
857 }
858 mDNS_Unlock(m);
859 }
860 }
861
862 mDNSlocal mStatus mDNSNetMonitor(void)
863 {
864 struct tm tm;
865 int h, m, s, mul, div, TotPkt;
866 sigset_t signals;
867
868 mStatus status = mDNS_Init(&mDNSStorage, &PlatformStorage,
869 mDNS_Init_NoCache, mDNS_Init_ZeroCacheSize,
870 mDNS_Init_DontAdvertiseLocalAddresses,
871 mDNS_Init_NoInitCallback, mDNS_Init_NoInitCallbackContext);
872 if (status) return(status);
873
874 gettimeofday(&tv_start, NULL);
875 mDNSPosixListenForSignalInEventLoop(SIGINT);
876 mDNSPosixListenForSignalInEventLoop(SIGTERM);
877
878 do
879 {
880 struct timeval timeout = { 0x3FFFFFFF, 0 }; // wait until SIGINT or SIGTERM
881 mDNSBool gotSomething;
882 mDNSPosixRunEventLoopOnce(&mDNSStorage, &timeout, &signals, &gotSomething);
883 }
884 while ( !( sigismember( &signals, SIGINT) || sigismember( &signals, SIGTERM)));
885
886 // Now display final summary
887 TotPkt = NumPktQ + NumPktL + NumPktR;
888 gettimeofday(&tv_end, NULL);
889 tv_interval = tv_end;
890 if (tv_start.tv_usec > tv_interval.tv_usec)
891 { tv_interval.tv_usec += 1000000; tv_interval.tv_sec--; }
892 tv_interval.tv_sec -= tv_start.tv_sec;
893 tv_interval.tv_usec -= tv_start.tv_usec;
894 h = (tv_interval.tv_sec / 3600);
895 m = (tv_interval.tv_sec % 3600) / 60;
896 s = (tv_interval.tv_sec % 60);
897 if (tv_interval.tv_sec > 10)
898 {
899 mul = 60;
900 div = tv_interval.tv_sec;
901 }
902 else
903 {
904 mul = 60000;
905 div = tv_interval.tv_sec * 1000 + tv_interval.tv_usec / 1000;
906 if (div == 0) div=1;
907 }
908
909 mprintf("\n\n");
910 localtime_r((time_t*)&tv_start.tv_sec, &tm);
911 mprintf("Started %3d:%02d:%02d.%06d\n", tm.tm_hour, tm.tm_min, tm.tm_sec, tv_start.tv_usec);
912 localtime_r((time_t*)&tv_end.tv_sec, &tm);
913 mprintf("End %3d:%02d:%02d.%06d\n", tm.tm_hour, tm.tm_min, tm.tm_sec, tv_end.tv_usec);
914 mprintf("Captured for %3d:%02d:%02d.%06d\n", h, m, s, tv_interval.tv_usec);
915 if (!Filters)
916 {
917 mprintf("Unique source addresses seen on network:");
918 if (IPv4HostList.num) mprintf(" %ld (IPv4)", IPv4HostList.num);
919 if (IPv6HostList.num) mprintf(" %ld (IPv6)", IPv6HostList.num);
920 if (!IPv4HostList.num && !IPv6HostList.num) mprintf(" None");
921 mprintf("\n");
922 }
923 mprintf("\n");
924 mprintf("Modern Query Packets: %7d (avg%5d/min)\n", NumPktQ, NumPktQ * mul / div);
925 mprintf("Legacy Query Packets: %7d (avg%5d/min)\n", NumPktL, NumPktL * mul / div);
926 mprintf("Multicast Response Packets: %7d (avg%5d/min)\n", NumPktR, NumPktR * mul / div);
927 mprintf("Total Multicast Packets: %7d (avg%5d/min)\n", TotPkt, TotPkt * mul / div);
928 mprintf("\n");
929 mprintf("Total New Service Probes: %7d (avg%5d/min)\n", NumProbes, NumProbes * mul / div);
930 mprintf("Total Goodbye Announcements: %7d (avg%5d/min)\n", NumGoodbyes, NumGoodbyes * mul / div);
931 mprintf("Total Query Questions: %7d (avg%5d/min)\n", NumQuestions, NumQuestions * mul / div);
932 mprintf("Total Queries from Legacy Clients:%7d (avg%5d/min)\n", NumLegacy, NumLegacy * mul / div);
933 mprintf("Total Answers/Announcements: %7d (avg%5d/min)\n", NumAnswers, NumAnswers * mul / div);
934 mprintf("Total Additional Records: %7d (avg%5d/min)\n", NumAdditionals, NumAdditionals * mul / div);
935 mprintf("\n");
936 printstats(kReportTopServices);
937
938 if (!ExactlyOneFilter)
939 {
940 ShowSortedHostList(&IPv4HostList, kReportTopHosts);
941 ShowSortedHostList(&IPv6HostList, kReportTopHosts);
942 }
943
944 mDNS_Close(&mDNSStorage);
945 return(0);
946 }
947
948 mDNSexport int main(int argc, char **argv)
949 {
950 const char *progname = strrchr(argv[0], '/') ? strrchr(argv[0], '/') + 1 : argv[0];
951 int i;
952 mStatus status;
953
954 setlinebuf(stdout); // Want to see lines as they appear, not block buffered
955
956 for (i=1; i<argc; i++)
957 {
958 if (i+1 < argc && !strcmp(argv[i], "-i") && atoi(argv[i+1]))
959 {
960 FilterInterface = atoi(argv[i+1]);
961 i += 2;
962 printf("Monitoring interface %d\n", FilterInterface);
963 }
964 else
965 {
966 struct in_addr s4;
967 struct in6_addr s6;
968 FilterList *f;
969 mDNSAddr a;
970 a.type = mDNSAddrType_IPv4;
971
972 if (inet_pton(AF_INET, argv[i], &s4) == 1)
973 a.ip.v4.NotAnInteger = s4.s_addr;
974 else if (inet_pton(AF_INET6, argv[i], &s6) == 1)
975 {
976 a.type = mDNSAddrType_IPv6;
977 mDNSPlatformMemCopy(&a.ip.v6, &s6, sizeof(a.ip.v6));
978 }
979 else
980 {
981 struct hostent *h = gethostbyname(argv[i]);
982 if (h) a.ip.v4.NotAnInteger = *(long*)h->h_addr;
983 else goto usage;
984 }
985
986 f = malloc(sizeof(*f));
987 f->FilterAddr = a;
988 f->next = Filters;
989 Filters = f;
990 }
991 }
992
993 status = mDNSNetMonitor();
994 if (status) { fprintf(stderr, "%s: mDNSNetMonitor failed %d\n", progname, (int)status); return(status); }
995 return(0);
996
997 usage:
998 fprintf(stderr, "\nmDNS traffic monitor\n");
999 fprintf(stderr, "Usage: %s (<host>)\n", progname);
1000 fprintf(stderr, "Optional <host> parameter displays only packets from that host\n");
1001
1002 fprintf(stderr, "\nPer-packet header output:\n");
1003 fprintf(stderr, "-Q- Multicast Query from mDNS client that accepts multicast responses\n");
1004 fprintf(stderr, "-R- Multicast Response packet containing answers/announcements\n");
1005 fprintf(stderr, "-LQ- Multicast Query from legacy client that does *not* listen for multicast responses\n");
1006 fprintf(stderr, "Q/Ans/Auth/Add Number of questions, answers, authority records and additional records in packet\n");
1007
1008 fprintf(stderr, "\nPer-record display:\n");
1009 fprintf(stderr, "(PM) Probe Question (new service starting), requesting multicast response\n");
1010 fprintf(stderr, "(PU) Probe Question (new service starting), requesting unicast response\n");
1011 fprintf(stderr, "(DE) Deletion/Goodbye (service going away)\n");
1012 fprintf(stderr, "(LQ) Legacy Query Question\n");
1013 fprintf(stderr, "(QM) Query Question, requesting multicast response\n");
1014 fprintf(stderr, "(QU) Query Question, requesting unicast response\n");
1015 fprintf(stderr, "(KA) Known Answer (information querier already knows)\n");
1016 fprintf(stderr, "(AN) Unique Answer to question (or periodic announcment) (entire RR Set)\n");
1017 fprintf(stderr, "(AN+) Answer to question (or periodic announcment) (add to existing RR Set members)\n");
1018 fprintf(stderr, "(AD) Unique Additional Record Set (entire RR Set)\n");
1019 fprintf(stderr, "(AD+) Additional records (add to existing RR Set members)\n");
1020
1021 fprintf(stderr, "\nFinal summary, sorted by service type:\n");
1022 fprintf(stderr, "Probe Probes for this service type starting up\n");
1023 fprintf(stderr, "Goodbye Goodbye (deletion) packets for this service type shutting down\n");
1024 fprintf(stderr, "BrowseQ Browse questions from clients browsing to find a list of instances of this service\n");
1025 fprintf(stderr, "BrowseA Browse answers/announcments advertising instances of this service\n");
1026 fprintf(stderr, "ResolveQ Resolve questions from clients actively connecting to an instance of this service\n");
1027 fprintf(stderr, "ResolveA Resolve answers/announcments giving connection information for an instance of this service\n");
1028 fprintf(stderr, "\n");
1029 return(-1);
1030 }
mirror of mDNSResponder