git.meshlink.io Git - catta/blob - avahi-core/server.c

   1 /***
   2   This file is part of avahi.
   3
   4   avahi is free software; you can redistribute it and/or modify it
   5   under the terms of the GNU Lesser General Public License as
   6   published by the Free Software Foundation; either version 2.1 of the
   7   License, or (at your option) any later version.
   8
   9   avahi is distributed in the hope that it will be useful, but WITHOUT
  10   ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  11   or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General
  12   Public License for more details.
  13
  14   You should have received a copy of the GNU Lesser General Public
  15   License along with avahi; if not, write to the Free Software
  16   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
  17   USA.
  18 ***/
  19
  20 #ifdef HAVE_CONFIG_H
  21 #include <config.h>
  22 #endif
  23
  24 #include <sys/types.h>
  25 #include <sys/socket.h>
  26 #include <netinet/in.h>
  27 #include <arpa/inet.h>
  28 #include <string.h>
  29 #include <sys/utsname.h>
  30 #include <unistd.h>
  31 #include <errno.h>
  32 #include <stdio.h>
  33 #include <assert.h>
  34 #include <stdlib.h>
  35
  36 #include <avahi-common/domain.h>
  37 #include <avahi-common/timeval.h>
  38 #include <avahi-common/malloc.h>
  39 #include <avahi-common/error.h>
  40
  41 #include "internal.h"
  42 #include "iface.h"
  43 #include "socket.h"
  44 #include "browse.h"
  45 #include "log.h"
  46 #include "util.h"
  47 #include "dns-srv-rr.h"
  48 #include "addr-util.h"
  49 #include "domain-util.h"
  50 #include "rr-util.h"
  51
  52 #define AVAHI_DEFAULT_CACHE_ENTRIES_MAX 500
  53
  54 static void enum_aux_records(AvahiServer *s, AvahiInterface *i, const char *name, uint16_t type, void (*callback)(AvahiServer *s, AvahiRecord *r, int flush_cache, void* userdata), void* userdata) {
  55     assert(s);
  56     assert(i);
  57     assert(name);
  58     assert(callback);
  59
  60     if (type == AVAHI_DNS_TYPE_ANY) {
  61         AvahiEntry *e;
  62
  63         for (e = s->entries; e; e = e->entries_next)
  64             if (!e->dead &&
  65                 avahi_entry_is_registered(s, e, i) &&
  66                 e->record->key->clazz == AVAHI_DNS_CLASS_IN &&
  67                 avahi_domain_equal(name, e->record->key->name))
  68                 callback(s, e->record, e->flags & AVAHI_PUBLISH_UNIQUE, userdata);
  69
  70     } else {
  71         AvahiEntry *e;
  72         AvahiKey *k;
  73
  74         if (!(k = avahi_key_new(name, AVAHI_DNS_CLASS_IN, type)))
  75             return; /** OOM */
  76
  77         for (e = avahi_hashmap_lookup(s->entries_by_key, k); e; e = e->by_key_next)
  78             if (!e->dead && avahi_entry_is_registered(s, e, i))
  79                 callback(s, e->record, e->flags & AVAHI_PUBLISH_UNIQUE, userdata);
  80
  81         avahi_key_unref(k);
  82     }
  83 }
  84
  85 void avahi_server_enumerate_aux_records(AvahiServer *s, AvahiInterface *i, AvahiRecord *r, void (*callback)(AvahiServer *s, AvahiRecord *r, int flush_cache, void* userdata), void* userdata) {
  86     assert(s);
  87     assert(i);
  88     assert(r);
  89     assert(callback);
  90
  91     /* Call the specified callback far all records referenced by the one specified in *r */
  92
  93     if (r->key->clazz == AVAHI_DNS_CLASS_IN) {
  94         if (r->key->type == AVAHI_DNS_TYPE_PTR) {
  95             enum_aux_records(s, i, r->data.ptr.name, AVAHI_DNS_TYPE_SRV, callback, userdata);
  96             enum_aux_records(s, i, r->data.ptr.name, AVAHI_DNS_TYPE_TXT, callback, userdata);
  97         } else if (r->key->type == AVAHI_DNS_TYPE_SRV) {
  98             enum_aux_records(s, i, r->data.srv.name, AVAHI_DNS_TYPE_A, callback, userdata);
  99             enum_aux_records(s, i, r->data.srv.name, AVAHI_DNS_TYPE_AAAA, callback, userdata);
 100         } else if (r->key->type == AVAHI_DNS_TYPE_CNAME)
 101             enum_aux_records(s, i, r->data.cname.name, AVAHI_DNS_TYPE_ANY, callback, userdata);
 102     }
 103 }
 104
 105 void avahi_server_prepare_response(AvahiServer *s, AvahiInterface *i, AvahiEntry *e, int unicast_response, int auxiliary) {
 106     assert(s);
 107     assert(i);
 108     assert(e);
 109
 110     avahi_record_list_push(s->record_list, e->record, e->flags & AVAHI_PUBLISH_UNIQUE, unicast_response, auxiliary);
 111 }
 112
 113 void avahi_server_prepare_matching_responses(AvahiServer *s, AvahiInterface *i, AvahiKey *k, int unicast_response) {
 114     assert(s);
 115     assert(i);
 116     assert(k);
 117
 118     /* Push all records that match the specified key to the record list */
 119
 120     if (avahi_key_is_pattern(k)) {
 121         AvahiEntry *e;
 122
 123         /* Handle ANY query */
 124
 125         for (e = s->entries; e; e = e->entries_next)
 126             if (!e->dead && avahi_key_pattern_match(k, e->record->key) && avahi_entry_is_registered(s, e, i))
 127                 avahi_server_prepare_response(s, i, e, unicast_response, 0);
 128
 129     } else {
 130         AvahiEntry *e;
 131
 132         /* Handle all other queries */
 133
 134         for (e = avahi_hashmap_lookup(s->entries_by_key, k); e; e = e->by_key_next)
 135             if (!e->dead && avahi_entry_is_registered(s, e, i))
 136                 avahi_server_prepare_response(s, i, e, unicast_response, 0);
 137     }
 138
 139     /* Look for CNAME records */
 140
 141     if ((k->clazz == AVAHI_DNS_CLASS_IN || k->clazz == AVAHI_DNS_CLASS_ANY)
 142         && k->type != AVAHI_DNS_TYPE_CNAME && k->type != AVAHI_DNS_TYPE_ANY) {
 143
 144         AvahiKey *cname_key;
 145
 146         if (!(cname_key = avahi_key_new(k->name, AVAHI_DNS_CLASS_IN, AVAHI_DNS_TYPE_CNAME)))
 147             return;
 148
 149         avahi_server_prepare_matching_responses(s, i, cname_key, unicast_response);
 150         avahi_key_unref(cname_key);
 151     }
 152 }
 153
 154 static void withdraw_entry(AvahiServer *s, AvahiEntry *e) {
 155     assert(s);
 156     assert(e);
 157
 158     /* Withdraw the specified entry, and if is part of an entry group,
 159      * put that into COLLISION state */
 160
 161     if (e->dead)
 162         return;
 163
 164     if (e->group) {
 165         AvahiEntry *k;
 166
 167         for (k = e->group->entries; k; k = k->by_group_next)
 168             if (!k->dead) {
 169                 avahi_goodbye_entry(s, k, 0, 1);
 170                 k->dead = 1;
 171             }
 172
 173         e->group->n_probing = 0;
 174
 175         avahi_s_entry_group_change_state(e->group, AVAHI_ENTRY_GROUP_COLLISION);
 176     } else {
 177         avahi_goodbye_entry(s, e, 0, 1);
 178         e->dead = 1;
 179     }
 180
 181     s->need_entry_cleanup = 1;
 182 }
 183
 184 static void withdraw_rrset(AvahiServer *s, AvahiKey *key) {
 185     AvahiEntry *e;
 186
 187     assert(s);
 188     assert(key);
 189
 190     /* Withdraw an entry RRSset */
 191
 192     for (e = avahi_hashmap_lookup(s->entries_by_key, key); e; e = e->by_key_next)
 193         withdraw_entry(s, e);
 194 }
 195
 196 static void incoming_probe(AvahiServer *s, AvahiRecord *record, AvahiInterface *i) {
 197     AvahiEntry *e, *n;
 198     int ours = 0, won = 0, lost = 0;
 199
 200     assert(s);
 201     assert(record);
 202     assert(i);
 203
 204     /* Handle incoming probes and check if they conflict our own probes */
 205
 206     for (e = avahi_hashmap_lookup(s->entries_by_key, record->key); e; e = n) {
 207         int cmp;
 208         n = e->by_key_next;
 209
 210         if (e->dead)
 211             continue;
 212
 213         if ((cmp = avahi_record_lexicographical_compare(e->record, record)) == 0) {
 214             ours = 1;
 215             break;
 216         } else {
 217
 218             if (avahi_entry_is_probing(s, e, i)) {
 219                 if (cmp > 0)
 220                     won = 1;
 221                 else /* cmp < 0 */
 222                     lost = 1;
 223             }
 224         }
 225     }
 226
 227     if (!ours) {
 228         char *t = avahi_record_to_string(record);
 229
 230         if (won)
 231             avahi_log_debug("Received conflicting probe [%s]. Local host won.", t);
 232         else if (lost) {
 233             avahi_log_debug("Received conflicting probe [%s]. Local host lost. Withdrawing.", t);
 234             withdraw_rrset(s, record->key);
 235         }
 236
 237         avahi_free(t);
 238     }
 239 }
 240
 241 static int handle_conflict(AvahiServer *s, AvahiInterface *i, AvahiRecord *record, int unique) {
 242     int valid = 1, ours = 0, conflict = 0, withdraw_immediately = 0;
 243     AvahiEntry *e, *n, *conflicting_entry = NULL;
 244
 245     assert(s);
 246     assert(i);
 247     assert(record);
 248
 249     /* Check whether an incoming record conflicts with one of our own */
 250
 251     for (e = avahi_hashmap_lookup(s->entries_by_key, record->key); e; e = n) {
 252         n = e->by_key_next;
 253
 254         if (e->dead)
 255             continue;
 256
 257         /* Check if the incoming is a goodbye record */
 258         if (avahi_record_is_goodbye(record)) {
 259
 260             if (avahi_record_equal_no_ttl(e->record, record)) {
 261                 char *t;
 262
 263                 /* Refresh */
 264                 t = avahi_record_to_string(record);
 265                 avahi_log_debug("Received goodbye record for one of our records [%s]. Refreshing.", t);
 266                 avahi_server_prepare_matching_responses(s, i, e->record->key, 0);
 267
 268                 valid = 0;
 269                 avahi_free(t);
 270                 break;
 271             }
 272
 273             /* If the goodybe packet doesn't match one of our own RRs, we simply ignore it. */
 274             continue;
 275         }
 276
 277         if (!(e->flags & AVAHI_PUBLISH_UNIQUE) && !unique)
 278             continue;
 279
 280         /* Either our entry or the other is intended to be unique, so let's check */
 281
 282         if (avahi_record_equal_no_ttl(e->record, record)) {
 283             ours = 1; /* We have an identical record, so this is no conflict */
 284
 285             /* Check wheter there is a TTL conflict */
 286             if (record->ttl <= e->record->ttl/2 &&
 287                 avahi_entry_is_registered(s, e, i)) {
 288                 char *t;
 289                 /* Refresh */
 290                 t = avahi_record_to_string(record);
 291
 292                 avahi_log_debug("Received record with bad TTL [%s]. Refreshing.", t);
 293                 avahi_server_prepare_matching_responses(s, i, e->record->key, 0);
 294                 valid = 0;
 295
 296                 avahi_free(t);
 297             }
 298
 299             /* There's no need to check the other entries of this RRset */
 300             break;
 301
 302         } else {
 303
 304             if (avahi_entry_is_registered(s, e, i)) {
 305
 306                 /* A conflict => we have to return to probe mode */
 307                 conflict = 1;
 308                 conflicting_entry = e;
 309
 310             } else if (avahi_entry_is_probing(s, e, i)) {
 311
 312                 /* We are currently registering a matching record, but
 313                  * someone else already claimed it, so let's
 314                  * withdraw */
 315                 conflict = 1;
 316                 withdraw_immediately = 1;
 317             }
 318         }
 319     }
 320
 321     if (!ours && conflict) {
 322         char *t;
 323
 324         valid = 0;
 325
 326         t = avahi_record_to_string(record);
 327
 328         if (withdraw_immediately) {
 329             avahi_log_debug("Received conflicting record [%s] with local record to be. Withdrawing.", t);
 330             withdraw_rrset(s, record->key);
 331         } else {
 332             assert(conflicting_entry);
 333             avahi_log_debug("Received conflicting record [%s]. Resetting our record.", t);
 334             avahi_entry_return_to_initial_state(s, conflicting_entry, i);
 335
 336             /* Local unique records are returned to probing
 337              * state. Local shared records are reannounced. */
 338         }
 339
 340         avahi_free(t);
 341     }
 342
 343     return valid;
 344 }
 345
 346 static void append_aux_callback(AvahiServer *s, AvahiRecord *r, int flush_cache, void* userdata) {
 347     int *unicast_response = userdata;
 348
 349     assert(s);
 350     assert(r);
 351     assert(unicast_response);
 352
 353     avahi_record_list_push(s->record_list, r, flush_cache, *unicast_response, 1);
 354 }
 355
 356 static void append_aux_records_to_list(AvahiServer *s, AvahiInterface *i, AvahiRecord *r, int unicast_response) {
 357     assert(s);
 358     assert(r);
 359
 360     avahi_server_enumerate_aux_records(s, i, r, append_aux_callback, &unicast_response);
 361 }
 362
 363 void avahi_server_generate_response(AvahiServer *s, AvahiInterface *i, AvahiDnsPacket *p, const AvahiAddress *a, uint16_t port, int legacy_unicast, int immediately) {
 364
 365     assert(s);
 366     assert(i);
 367     assert(!legacy_unicast || (a && port > 0 && p));
 368
 369     if (legacy_unicast) {
 370         AvahiDnsPacket *reply;
 371         AvahiRecord *r;
 372
 373         if (!(reply = avahi_dns_packet_new_reply(p, 512 + AVAHI_DNS_PACKET_EXTRA_SIZE /* unicast DNS maximum packet size is 512 */ , 1, 1)))
 374             return; /* OOM */
 375
 376         while ((r = avahi_record_list_next(s->record_list, NULL, NULL, NULL))) {
 377
 378             append_aux_records_to_list(s, i, r, 0);
 379
 380             if (avahi_dns_packet_append_record(reply, r, 0, 10))
 381                 avahi_dns_packet_inc_field(reply, AVAHI_DNS_FIELD_ANCOUNT);
 382             else {
 383                 char *t = avahi_record_to_string(r);
 384                 avahi_log_warn("Record [%s] not fitting in legacy unicast packet, dropping.", t);
 385                 avahi_free(t);
 386             }
 387
 388             avahi_record_unref(r);
 389         }
 390
 391         if (avahi_dns_packet_get_field(reply, AVAHI_DNS_FIELD_ANCOUNT) != 0)
 392             avahi_interface_send_packet_unicast(i, reply, a, port);
 393
 394         avahi_dns_packet_free(reply);
 395
 396     } else {
 397         int unicast_response, flush_cache, auxiliary;
 398         AvahiDnsPacket *reply = NULL;
 399         AvahiRecord *r;
 400
 401         /* In case the query packet was truncated never respond
 402         immediately, because known answer suppression records might be
 403         contained in later packets */
 404         int tc = p && !!(avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_FLAGS) & AVAHI_DNS_FLAG_TC);
 405
 406         while ((r = avahi_record_list_next(s->record_list, &flush_cache, &unicast_response, &auxiliary))) {
 407
 408             int im = immediately;
 409
 410             /* Only send the response immediately if it contains a
 411              * unique entry AND it is not in reply to a truncated
 412              * packet AND it is not an auxiliary record AND all other
 413              * responses for this record are unique too. */
 414
 415             if (flush_cache && !tc && !auxiliary && avahi_record_list_all_flush_cache(s->record_list))
 416                 im = 1;
 417
 418             if (!avahi_interface_post_response(i, r, flush_cache, a, im) && unicast_response) {
 419
 420                 /* Due to some reasons the record has not been scheduled.
 421                  * The client requested an unicast response in that
 422                  * case. Therefore we prepare such a response */
 423
 424                 append_aux_records_to_list(s, i, r, unicast_response);
 425
 426                 for (;;) {
 427
 428                     if (!reply) {
 429                         assert(p);
 430
 431                         if (!(reply = avahi_dns_packet_new_reply(p, i->hardware->mtu, 0, 0)))
 432                             break; /* OOM */
 433                     }
 434
 435                     if (avahi_dns_packet_append_record(reply, r, flush_cache, 0)) {
 436
 437                         /* Appending this record succeeded, so incremeant
 438                          * the specific header field, and return to the caller */
 439
 440                         avahi_dns_packet_inc_field(reply, AVAHI_DNS_FIELD_ANCOUNT);
 441                         break;
 442                     }
 443
 444                     if (avahi_dns_packet_get_field(reply, AVAHI_DNS_FIELD_ANCOUNT) == 0) {
 445                         size_t size;
 446
 447                         /* The record is too large for one packet, so create a larger packet */
 448
 449                         avahi_dns_packet_free(reply);
 450                         size = avahi_record_get_estimate_size(r) + AVAHI_DNS_PACKET_HEADER_SIZE;
 451
 452                         if (!(reply = avahi_dns_packet_new_reply(p, size + AVAHI_DNS_PACKET_EXTRA_SIZE, 0, 1)))
 453                             break; /* OOM */
 454
 455                         if (avahi_dns_packet_append_record(reply, r, flush_cache, 0)) {
 456
 457                             /* Appending this record succeeded, so incremeant
 458                              * the specific header field, and return to the caller */
 459
 460                             avahi_dns_packet_inc_field(reply, AVAHI_DNS_FIELD_ANCOUNT);
 461                             break;
 462
 463                         }  else {
 464
 465                             /* We completely fucked up, there's
 466                              * nothing we can do. The RR just doesn't
 467                              * fit in. Let's ignore it. */
 468
 469                             char *t;
 470                             avahi_dns_packet_free(reply);
 471                             reply = NULL;
 472                             t = avahi_record_to_string(r);
 473                             avahi_log_warn("Record [%s] too large, doesn't fit in any packet!", t);
 474                             avahi_free(t);
 475                             break;
 476                         }
 477                     }
 478
 479                     /* Appending the record didn't succeeed, so let's send this packet, and create a new one */
 480                     avahi_interface_send_packet_unicast(i, reply, a, port);
 481                     avahi_dns_packet_free(reply);
 482                     reply = NULL;
 483                 }
 484             }
 485
 486             avahi_record_unref(r);
 487         }
 488
 489         if (reply) {
 490             if (avahi_dns_packet_get_field(reply, AVAHI_DNS_FIELD_ANCOUNT) != 0)
 491                 avahi_interface_send_packet_unicast(i, reply, a, port);
 492             avahi_dns_packet_free(reply);
 493         }
 494     }
 495
 496     avahi_record_list_flush(s->record_list);
 497 }
 498
 499 static void reflect_response(AvahiServer *s, AvahiInterface *i, AvahiRecord *r, int flush_cache) {
 500     AvahiInterface *j;
 501
 502     assert(s);
 503     assert(i);
 504     assert(r);
 505
 506     if (!s->config.enable_reflector)
 507         return;
 508
 509     for (j = s->monitor->interfaces; j; j = j->interface_next)
 510         if (j != i && (s->config.reflect_ipv || j->protocol == i->protocol))
 511             avahi_interface_post_response(j, r, flush_cache, NULL, 1);
 512 }
 513
 514 static void* reflect_cache_walk_callback(AvahiCache *c, AvahiKey *pattern, AvahiCacheEntry *e, void* userdata) {
 515     AvahiServer *s = userdata;
 516
 517     assert(c);
 518     assert(pattern);
 519     assert(e);
 520     assert(s);
 521
 522     avahi_record_list_push(s->record_list, e->record, e->cache_flush, 0, 0);
 523     return NULL;
 524 }
 525
 526 static void reflect_query(AvahiServer *s, AvahiInterface *i, AvahiKey *k) {
 527     AvahiInterface *j;
 528
 529     assert(s);
 530     assert(i);
 531     assert(k);
 532
 533     if (!s->config.enable_reflector)
 534         return;
 535
 536     for (j = s->monitor->interfaces; j; j = j->interface_next)
 537         if (j != i && (s->config.reflect_ipv || j->protocol == i->protocol)) {
 538             /* Post the query to other networks */
 539             avahi_interface_post_query(j, k, 1, NULL);
 540
 541             /* Reply from caches of other network. This is needed to
 542              * "work around" known answer suppression. */
 543
 544             avahi_cache_walk(j->cache, k, reflect_cache_walk_callback, s);
 545         }
 546 }
 547
 548 static void reflect_probe(AvahiServer *s, AvahiInterface *i, AvahiRecord *r) {
 549     AvahiInterface *j;
 550
 551     assert(s);
 552     assert(i);
 553     assert(r);
 554
 555     if (!s->config.enable_reflector)
 556         return;
 557
 558     for (j = s->monitor->interfaces; j; j = j->interface_next)
 559         if (j != i && (s->config.reflect_ipv || j->protocol == i->protocol))
 560             avahi_interface_post_probe(j, r, 1);
 561 }
 562
 563 static void handle_query_packet(AvahiServer *s, AvahiDnsPacket *p, AvahiInterface *i, const AvahiAddress *a, uint16_t port, int legacy_unicast, int from_local_iface) {
 564     size_t n;
 565     int is_probe;
 566
 567     assert(s);
 568     assert(p);
 569     assert(i);
 570     assert(a);
 571
 572     assert(avahi_record_list_is_empty(s->record_list));
 573
 574     is_probe = avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_NSCOUNT) > 0;
 575
 576     /* Handle the questions */
 577     for (n = avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_QDCOUNT); n > 0; n --) {
 578         AvahiKey *key;
 579         int unicast_response = 0;
 580
 581         if (!(key = avahi_dns_packet_consume_key(p, &unicast_response))) {
 582             avahi_log_warn(__FILE__": Packet too short or invalid while reading question key. (Maybe a UTF-8 problem?)");
 583             goto fail;
 584         }
 585
 586         if (!legacy_unicast && !from_local_iface) {
 587             reflect_query(s, i, key);
 588             if (!unicast_response)
 589               avahi_cache_start_poof(i->cache, key, a);
 590         }
 591
 592         if (avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_ANCOUNT) == 0 &&
 593             !(avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_FLAGS) & AVAHI_DNS_FLAG_TC))
 594             /* Allow our own queries to be suppressed by incoming
 595              * queries only when they do not include known answers */
 596             avahi_query_scheduler_incoming(i->query_scheduler, key);
 597
 598         avahi_server_prepare_matching_responses(s, i, key, unicast_response);
 599         avahi_key_unref(key);
 600     }
 601
 602     if (!legacy_unicast) {
 603
 604         /* Known Answer Suppression */
 605         for (n = avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_ANCOUNT); n > 0; n --) {
 606             AvahiRecord *record;
 607             int unique = 0;
 608
 609             if (!(record = avahi_dns_packet_consume_record(p, &unique))) {
 610                 avahi_log_warn(__FILE__": Packet too short or invalid while reading known answer record. (Maybe a UTF-8 problem?)");
 611                 goto fail;
 612             }
 613
 614             avahi_response_scheduler_suppress(i->response_scheduler, record, a);
 615             avahi_record_list_drop(s->record_list, record);
 616             avahi_cache_stop_poof(i->cache, record, a);
 617
 618             avahi_record_unref(record);
 619         }
 620
 621         /* Probe record */
 622         for (n = avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_NSCOUNT); n > 0; n --) {
 623             AvahiRecord *record;
 624             int unique = 0;
 625
 626             if (!(record = avahi_dns_packet_consume_record(p, &unique))) {
 627                 avahi_log_warn(__FILE__": Packet too short or invalid while reading probe record. (Maybe a UTF-8 problem?)");
 628                 goto fail;
 629             }
 630
 631             if (!avahi_key_is_pattern(record->key)) {
 632                 if (!from_local_iface)
 633                     reflect_probe(s, i, record);
 634                 incoming_probe(s, record, i);
 635             }
 636
 637             avahi_record_unref(record);
 638         }
 639     }
 640
 641     if (!avahi_record_list_is_empty(s->record_list))
 642         avahi_server_generate_response(s, i, p, a, port, legacy_unicast, is_probe);
 643
 644     return;
 645
 646 fail:
 647     avahi_record_list_flush(s->record_list);
 648 }
 649
 650 static void handle_response_packet(AvahiServer *s, AvahiDnsPacket *p, AvahiInterface *i, const AvahiAddress *a, int from_local_iface) {
 651     unsigned n;
 652
 653     assert(s);
 654     assert(p);
 655     assert(i);
 656     assert(a);
 657
 658     for (n = avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_ANCOUNT) +
 659              avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_ARCOUNT); n > 0; n--) {
 660         AvahiRecord *record;
 661         int cache_flush = 0;
 662
 663         if (!(record = avahi_dns_packet_consume_record(p, &cache_flush))) {
 664             avahi_log_warn(__FILE__": Packet too short or invalid while reading response record. (Maybe a UTF-8 problem?)");
 665             break;
 666         }
 667
 668         if (!avahi_key_is_pattern(record->key)) {
 669
 670             if (handle_conflict(s, i, record, cache_flush)) {
 671                 if (!from_local_iface && !avahi_record_is_link_local_address(record))
 672                     reflect_response(s, i, record, cache_flush);
 673                 avahi_cache_update(i->cache, record, cache_flush, a);
 674                 avahi_response_scheduler_incoming(i->response_scheduler, record, cache_flush);
 675             }
 676         }
 677
 678         avahi_record_unref(record);
 679     }
 680
 681     /* If the incoming response contained a conflicting record, some
 682        records have been scheduled for sending. We need to flush them
 683        here. */
 684     if (!avahi_record_list_is_empty(s->record_list))
 685         avahi_server_generate_response(s, i, NULL, NULL, 0, 0, 1);
 686 }
 687
 688 static AvahiLegacyUnicastReflectSlot* allocate_slot(AvahiServer *s) {
 689     unsigned n, idx = (unsigned) -1;
 690     AvahiLegacyUnicastReflectSlot *slot;
 691
 692     assert(s);
 693
 694     if (!s->legacy_unicast_reflect_slots)
 695         s->legacy_unicast_reflect_slots = avahi_new0(AvahiLegacyUnicastReflectSlot*, AVAHI_LEGACY_UNICAST_REFLECT_SLOTS_MAX);
 696
 697     for (n = 0; n < AVAHI_LEGACY_UNICAST_REFLECT_SLOTS_MAX; n++, s->legacy_unicast_reflect_id++) {
 698         idx = s->legacy_unicast_reflect_id % AVAHI_LEGACY_UNICAST_REFLECT_SLOTS_MAX;
 699
 700         if (!s->legacy_unicast_reflect_slots[idx])
 701             break;
 702     }
 703
 704     if (idx == (unsigned) -1 || s->legacy_unicast_reflect_slots[idx])
 705         return NULL;
 706
 707     if (!(slot = avahi_new(AvahiLegacyUnicastReflectSlot, 1)))
 708         return NULL; /* OOM */
 709
 710     s->legacy_unicast_reflect_slots[idx] = slot;
 711     slot->id = s->legacy_unicast_reflect_id++;
 712     slot->server = s;
 713
 714     return slot;
 715 }
 716
 717 static void deallocate_slot(AvahiServer *s, AvahiLegacyUnicastReflectSlot *slot) {
 718     unsigned idx;
 719
 720     assert(s);
 721     assert(slot);
 722
 723     idx = slot->id % AVAHI_LEGACY_UNICAST_REFLECT_SLOTS_MAX;
 724
 725     assert(s->legacy_unicast_reflect_slots[idx] == slot);
 726
 727     avahi_time_event_free(slot->time_event);
 728
 729     avahi_free(slot);
 730     s->legacy_unicast_reflect_slots[idx] = NULL;
 731 }
 732
 733 static void free_slots(AvahiServer *s) {
 734     unsigned idx;
 735     assert(s);
 736
 737     if (!s->legacy_unicast_reflect_slots)
 738         return;
 739
 740     for (idx = 0; idx < AVAHI_LEGACY_UNICAST_REFLECT_SLOTS_MAX; idx ++)
 741         if (s->legacy_unicast_reflect_slots[idx])
 742             deallocate_slot(s, s->legacy_unicast_reflect_slots[idx]);
 743
 744     avahi_free(s->legacy_unicast_reflect_slots);
 745     s->legacy_unicast_reflect_slots = NULL;
 746 }
 747
 748 static AvahiLegacyUnicastReflectSlot* find_slot(AvahiServer *s, uint16_t id) {
 749     unsigned idx;
 750
 751     assert(s);
 752
 753     if (!s->legacy_unicast_reflect_slots)
 754         return NULL;
 755
 756     idx = id % AVAHI_LEGACY_UNICAST_REFLECT_SLOTS_MAX;
 757
 758     if (!s->legacy_unicast_reflect_slots[idx] || s->legacy_unicast_reflect_slots[idx]->id != id)
 759         return NULL;
 760
 761     return s->legacy_unicast_reflect_slots[idx];
 762 }
 763
 764 static void legacy_unicast_reflect_slot_timeout(AvahiTimeEvent *e, void *userdata) {
 765     AvahiLegacyUnicastReflectSlot *slot = userdata;
 766
 767     assert(e);
 768     assert(slot);
 769     assert(slot->time_event == e);
 770
 771     deallocate_slot(slot->server, slot);
 772 }
 773
 774 static void reflect_legacy_unicast_query_packet(AvahiServer *s, AvahiDnsPacket *p, AvahiInterface *i, const AvahiAddress *a, uint16_t port) {
 775     AvahiLegacyUnicastReflectSlot *slot;
 776     AvahiInterface *j;
 777
 778     assert(s);
 779     assert(p);
 780     assert(i);
 781     assert(a);
 782     assert(port > 0);
 783     assert(i->protocol == a->proto);
 784
 785     if (!s->config.enable_reflector)
 786         return;
 787
 788     /* Reflecting legacy unicast queries is a little more complicated
 789        than reflecting normal queries, since we must route the
 790        responses back to the right client. Therefore we must store
 791        some information for finding the right client contact data for
 792        response packets. In contrast to normal queries legacy
 793        unicast query and response packets are reflected untouched and
 794        are not reassembled into larger packets */
 795
 796     if (!(slot = allocate_slot(s))) {
 797         /* No slot available, we drop this legacy unicast query */
 798         avahi_log_warn("No slot available for legacy unicast reflection, dropping query packet.");
 799         return;
 800     }
 801
 802     slot->original_id = avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_ID);
 803     slot->address = *a;
 804     slot->port = port;
 805     slot->interface = i->hardware->index;
 806
 807     avahi_elapse_time(&slot->elapse_time, 2000, 0);
 808     slot->time_event = avahi_time_event_new(s->time_event_queue, &slot->elapse_time, legacy_unicast_reflect_slot_timeout, slot);
 809
 810     /* Patch the packet with our new locally generatet id */
 811     avahi_dns_packet_set_field(p, AVAHI_DNS_FIELD_ID, slot->id);
 812
 813     for (j = s->monitor->interfaces; j; j = j->interface_next)
 814         if (j->announcing &&
 815             j != i &&
 816             (s->config.reflect_ipv || j->protocol == i->protocol)) {
 817
 818             if (j->protocol == AVAHI_PROTO_INET && s->fd_legacy_unicast_ipv4 >= 0) {
 819                 avahi_send_dns_packet_ipv4(s->fd_legacy_unicast_ipv4, j->hardware->index, p, NULL, NULL, 0);
 820             } else if (j->protocol == AVAHI_PROTO_INET6 && s->fd_legacy_unicast_ipv6 >= 0)
 821                 avahi_send_dns_packet_ipv6(s->fd_legacy_unicast_ipv6, j->hardware->index, p, NULL, NULL, 0);
 822         }
 823
 824     /* Reset the id */
 825     avahi_dns_packet_set_field(p, AVAHI_DNS_FIELD_ID, slot->original_id);
 826 }
 827
 828 static int originates_from_local_legacy_unicast_socket(AvahiServer *s, const AvahiAddress *address, uint16_t port) {
 829     assert(s);
 830     assert(address);
 831     assert(port > 0);
 832
 833     if (!s->config.enable_reflector)
 834         return 0;
 835
 836     if (!avahi_address_is_local(s->monitor, address))
 837         return 0;
 838
 839     if (address->proto == AVAHI_PROTO_INET && s->fd_legacy_unicast_ipv4 >= 0) {
 840         struct sockaddr_in lsa;
 841         socklen_t l = sizeof(lsa);
 842
 843         if (getsockname(s->fd_legacy_unicast_ipv4, (struct sockaddr*) &lsa, &l) != 0)
 844             avahi_log_warn("getsockname(): %s", strerror(errno));
 845         else
 846             return avahi_port_from_sockaddr((struct sockaddr*) &lsa) == port;
 847
 848     }
 849
 850     if (address->proto == AVAHI_PROTO_INET6 && s->fd_legacy_unicast_ipv6 >= 0) {
 851         struct sockaddr_in6 lsa;
 852         socklen_t l = sizeof(lsa);
 853
 854         if (getsockname(s->fd_legacy_unicast_ipv6, (struct sockaddr*) &lsa, &l) != 0)
 855             avahi_log_warn("getsockname(): %s", strerror(errno));
 856         else
 857             return avahi_port_from_sockaddr((struct sockaddr*) &lsa) == port;
 858     }
 859
 860     return 0;
 861 }
 862
 863 static int is_mdns_mcast_address(const AvahiAddress *a) {
 864     AvahiAddress b;
 865     assert(a);
 866
 867     avahi_address_parse(a->proto == AVAHI_PROTO_INET ? AVAHI_IPV4_MCAST_GROUP : AVAHI_IPV6_MCAST_GROUP, a->proto, &b);
 868     return avahi_address_cmp(a, &b) == 0;
 869 }
 870
 871 static int originates_from_local_iface(AvahiServer *s, AvahiIfIndex iface, const AvahiAddress *a, uint16_t port) {
 872     assert(s);
 873     assert(iface != AVAHI_IF_UNSPEC);
 874     assert(a);
 875
 876     /* If it isn't the MDNS port it can't be generated by us */
 877     if (port != AVAHI_MDNS_PORT)
 878         return 0;
 879
 880     return avahi_interface_has_address(s->monitor, iface, a);
 881 }
 882
 883 static void dispatch_packet(AvahiServer *s, AvahiDnsPacket *p, const AvahiAddress *src_address, uint16_t port, const AvahiAddress *dst_address, AvahiIfIndex iface, int ttl) {
 884     AvahiInterface *i;
 885     int from_local_iface = 0;
 886
 887     assert(s);
 888     assert(p);
 889     assert(src_address);
 890     assert(dst_address);
 891     assert(iface > 0);
 892     assert(src_address->proto == dst_address->proto);
 893
 894     if (!(i = avahi_interface_monitor_get_interface(s->monitor, iface, src_address->proto)) ||
 895         !i->announcing) {
 896         avahi_log_warn("Received packet from invalid interface.");
 897         return;
 898     }
 899
 900     if (port <= 0) {
 901         /* This fixes RHBZ #475394 */
 902         avahi_log_warn("Received packet from invalid source port %u.", (unsigned) port);
 903         return;
 904     }
 905
 906     if (avahi_address_is_ipv4_in_ipv6(src_address))
 907         /* This is an IPv4 address encapsulated in IPv6, so let's ignore it. */
 908         return;
 909
 910     if (originates_from_local_legacy_unicast_socket(s, src_address, port))
 911         /* This originates from our local reflector, so let's ignore it */
 912         return;
 913
 914     /* We don't want to reflect local traffic, so we check if this packet is generated locally. */
 915     if (s->config.enable_reflector)
 916         from_local_iface = originates_from_local_iface(s, iface, src_address, port);
 917
 918     if (avahi_dns_packet_check_valid_multicast(p) < 0) {
 919         avahi_log_warn("Received invalid packet.");
 920         return;
 921     }
 922
 923     if (avahi_dns_packet_is_query(p)) {
 924         int legacy_unicast = 0;
 925
 926         if (avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_ARCOUNT) != 0) {
 927             avahi_log_warn("Invalid query packet.");
 928             return;
 929         }
 930
 931         if (port != AVAHI_MDNS_PORT) {
 932             /* Legacy Unicast */
 933
 934             if ((avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_ANCOUNT) != 0 ||
 935                  avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_NSCOUNT) != 0)) {
 936                 avahi_log_warn("Invalid legacy unicast query packet.");
 937                 return;
 938             }
 939
 940             legacy_unicast = 1;
 941         }
 942
 943         if (legacy_unicast)
 944             reflect_legacy_unicast_query_packet(s, p, i, src_address, port);
 945
 946         handle_query_packet(s, p, i, src_address, port, legacy_unicast, from_local_iface);
 947
 948     } else {
 949         char t[AVAHI_ADDRESS_STR_MAX];
 950
 951         if (port != AVAHI_MDNS_PORT) {
 952             avahi_log_warn("Received response from host %s with invalid source port %u on interface '%s.%i'", avahi_address_snprint(t, sizeof(t), src_address), port, i->hardware->name, i->protocol);
 953             return;
 954         }
 955
 956         if (ttl != 255 && s->config.check_response_ttl) {
 957             avahi_log_warn("Received response from host %s with invalid TTL %u on interface '%s.%i'.", avahi_address_snprint(t, sizeof(t), src_address), ttl, i->hardware->name, i->protocol);
 958             return;
 959         }
 960
 961         if (!is_mdns_mcast_address(dst_address) &&
 962             !avahi_interface_address_on_link(i, src_address)) {
 963
 964             avahi_log_warn("Received non-local response from host %s on interface '%s.%i'.", avahi_address_snprint(t, sizeof(t), src_address), i->hardware->name, i->protocol);
 965             return;
 966         }
 967
 968         if (avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_QDCOUNT) != 0 ||
 969             avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_ANCOUNT) == 0 ||
 970             avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_NSCOUNT) != 0) {
 971
 972             avahi_log_warn("Invalid response packet from host %s.", avahi_address_snprint(t, sizeof(t), src_address));
 973             return;
 974         }
 975
 976         handle_response_packet(s, p, i, src_address, from_local_iface);
 977     }
 978 }
 979
 980 static void dispatch_legacy_unicast_packet(AvahiServer *s, AvahiDnsPacket *p) {
 981     AvahiInterface *j;
 982     AvahiLegacyUnicastReflectSlot *slot;
 983
 984     assert(s);
 985     assert(p);
 986
 987     if (avahi_dns_packet_check_valid(p) < 0 || avahi_dns_packet_is_query(p)) {
 988         avahi_log_warn("Received invalid packet.");
 989         return;
 990     }
 991
 992     if (!(slot = find_slot(s, avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_ID)))) {
 993         avahi_log_warn("Received legacy unicast response with unknown id");
 994         return;
 995     }
 996
 997     if (!(j = avahi_interface_monitor_get_interface(s->monitor, slot->interface, slot->address.proto)) ||
 998         !j->announcing)
 999         return;
1000
1001     /* Patch the original ID into this response */
1002     avahi_dns_packet_set_field(p, AVAHI_DNS_FIELD_ID, slot->original_id);
1003
1004     /* Forward the response to the correct client */
1005     avahi_interface_send_packet_unicast(j, p, &slot->address, slot->port);
1006
1007     /* Undo changes to packet */
1008     avahi_dns_packet_set_field(p, AVAHI_DNS_FIELD_ID, slot->id);
1009 }
1010
1011 static void mcast_socket_event(AvahiWatch *w, int fd, AvahiWatchEvent events, void *userdata) {
1012     AvahiServer *s = userdata;
1013     AvahiAddress dest, src;
1014     AvahiDnsPacket *p = NULL;
1015     AvahiIfIndex iface;
1016     uint16_t port;
1017     uint8_t ttl;
1018
1019     assert(w);
1020     assert(fd >= 0);
1021     assert(events & AVAHI_WATCH_IN);
1022
1023     if (fd == s->fd_ipv4) {
1024         dest.proto = src.proto = AVAHI_PROTO_INET;
1025         p = avahi_recv_dns_packet_ipv4(s->fd_ipv4, &src.data.ipv4, &port, &dest.data.ipv4, &iface, &ttl);
1026     } else {
1027         assert(fd == s->fd_ipv6);
1028         dest.proto = src.proto = AVAHI_PROTO_INET6;
1029         p = avahi_recv_dns_packet_ipv6(s->fd_ipv6, &src.data.ipv6, &port, &dest.data.ipv6, &iface, &ttl);
1030     }
1031
1032     if (p) {
1033         if (iface == AVAHI_IF_UNSPEC)
1034             iface = avahi_find_interface_for_address(s->monitor, &dest);
1035
1036         if (iface != AVAHI_IF_UNSPEC)
1037             dispatch_packet(s, p, &src, port, &dest, iface, ttl);
1038         else
1039             avahi_log_error("Incoming packet received on address that isn't local.");
1040
1041         avahi_dns_packet_free(p);
1042
1043         avahi_cleanup_dead_entries(s);
1044     }
1045 }
1046
1047 static void legacy_unicast_socket_event(AvahiWatch *w, int fd, AvahiWatchEvent events, void *userdata) {
1048     AvahiServer *s = userdata;
1049     AvahiDnsPacket *p = NULL;
1050
1051     assert(w);
1052     assert(fd >= 0);
1053     assert(events & AVAHI_WATCH_IN);
1054
1055     if (fd == s->fd_legacy_unicast_ipv4)
1056         p = avahi_recv_dns_packet_ipv4(s->fd_legacy_unicast_ipv4, NULL, NULL, NULL, NULL, NULL);
1057     else {
1058         assert(fd == s->fd_legacy_unicast_ipv6);
1059         p = avahi_recv_dns_packet_ipv6(s->fd_legacy_unicast_ipv6, NULL, NULL, NULL, NULL, NULL);
1060     }
1061
1062     if (p) {
1063         dispatch_legacy_unicast_packet(s, p);
1064         avahi_dns_packet_free(p);
1065
1066         avahi_cleanup_dead_entries(s);
1067     }
1068 }
1069
1070 static void server_set_state(AvahiServer *s, AvahiServerState state) {
1071     assert(s);
1072
1073     if (s->state == state)
1074         return;
1075
1076     s->state = state;
1077
1078     avahi_interface_monitor_update_rrs(s->monitor, 0);
1079
1080     if (s->callback)
1081         s->callback(s, state, s->userdata);
1082 }
1083
1084 static void withdraw_host_rrs(AvahiServer *s) {
1085     assert(s);
1086
1087     if (s->hinfo_entry_group)
1088         avahi_s_entry_group_reset(s->hinfo_entry_group);
1089
1090     if (s->browse_domain_entry_group)
1091         avahi_s_entry_group_reset(s->browse_domain_entry_group);
1092
1093     avahi_interface_monitor_update_rrs(s->monitor, 1);
1094     s->n_host_rr_pending = 0;
1095 }
1096
1097 void avahi_server_decrease_host_rr_pending(AvahiServer *s) {
1098     assert(s);
1099
1100     assert(s->n_host_rr_pending > 0);
1101
1102     if (--s->n_host_rr_pending == 0)
1103         server_set_state(s, AVAHI_SERVER_RUNNING);
1104 }
1105
1106 void avahi_host_rr_entry_group_callback(AvahiServer *s, AvahiSEntryGroup *g, AvahiEntryGroupState state, AVAHI_GCC_UNUSED void *userdata) {
1107     assert(s);
1108     assert(g);
1109
1110     if (state == AVAHI_ENTRY_GROUP_REGISTERING &&
1111         s->state == AVAHI_SERVER_REGISTERING)
1112         s->n_host_rr_pending ++;
1113
1114     else if (state == AVAHI_ENTRY_GROUP_COLLISION &&
1115         (s->state == AVAHI_SERVER_REGISTERING || s->state == AVAHI_SERVER_RUNNING)) {
1116         withdraw_host_rrs(s);
1117         server_set_state(s, AVAHI_SERVER_COLLISION);
1118
1119     } else if (state == AVAHI_ENTRY_GROUP_ESTABLISHED &&
1120                s->state == AVAHI_SERVER_REGISTERING)
1121         avahi_server_decrease_host_rr_pending(s);
1122 }
1123
1124 static void register_hinfo(AvahiServer *s) {
1125     struct utsname utsname;
1126     AvahiRecord *r;
1127
1128     assert(s);
1129
1130     if (!s->config.publish_hinfo)
1131         return;
1132
1133     if (s->hinfo_entry_group)
1134         assert(avahi_s_entry_group_is_empty(s->hinfo_entry_group));
1135     else
1136         s->hinfo_entry_group = avahi_s_entry_group_new(s, avahi_host_rr_entry_group_callback, NULL);
1137
1138     if (!s->hinfo_entry_group) {
1139         avahi_log_warn("Failed to create HINFO entry group: %s", avahi_strerror(s->error));
1140         return;
1141     }
1142
1143     /* Fill in HINFO rr */
1144     if ((r = avahi_record_new_full(s->host_name_fqdn, AVAHI_DNS_CLASS_IN, AVAHI_DNS_TYPE_HINFO, AVAHI_DEFAULT_TTL_HOST_NAME))) {
1145
1146         if (uname(&utsname) < 0)
1147             avahi_log_warn("uname() failed: %s\n", avahi_strerror(errno));
1148         else {
1149
1150             r->data.hinfo.cpu = avahi_strdup(avahi_strup(utsname.machine));
1151             r->data.hinfo.os = avahi_strdup(avahi_strup(utsname.sysname));
1152
1153             avahi_log_info("Registering HINFO record with values '%s'/'%s'.", r->data.hinfo.cpu, r->data.hinfo.os);
1154
1155             if (avahi_server_add(s, s->hinfo_entry_group, AVAHI_IF_UNSPEC, AVAHI_PROTO_UNSPEC, AVAHI_PUBLISH_UNIQUE, r) < 0) {
1156                 avahi_log_warn("Failed to add HINFO RR: %s", avahi_strerror(s->error));
1157                 return;
1158             }
1159         }
1160
1161         avahi_record_unref(r);
1162     }
1163
1164     if (avahi_s_entry_group_commit(s->hinfo_entry_group) < 0)
1165         avahi_log_warn("Failed to commit HINFO entry group: %s", avahi_strerror(s->error));
1166
1167 }
1168
1169 static void register_localhost(AvahiServer *s) {
1170     AvahiAddress a;
1171     assert(s);
1172
1173     /* Add localhost entries */
1174     avahi_address_parse("127.0.0.1", AVAHI_PROTO_INET, &a);
1175     avahi_server_add_address(s, NULL, AVAHI_IF_UNSPEC, AVAHI_PROTO_UNSPEC, AVAHI_PUBLISH_NO_PROBE|AVAHI_PUBLISH_NO_ANNOUNCE, "localhost", &a);
1176
1177     avahi_address_parse("::1", AVAHI_PROTO_INET6, &a);
1178     avahi_server_add_address(s, NULL, AVAHI_IF_UNSPEC, AVAHI_PROTO_UNSPEC, AVAHI_PUBLISH_NO_PROBE|AVAHI_PUBLISH_NO_ANNOUNCE, "ip6-localhost", &a);
1179 }
1180
1181 static void register_browse_domain(AvahiServer *s) {
1182     assert(s);
1183
1184     if (!s->config.publish_domain)
1185         return;
1186
1187     if (avahi_domain_equal(s->domain_name, "local"))
1188         return;
1189
1190     if (s->browse_domain_entry_group)
1191         assert(avahi_s_entry_group_is_empty(s->browse_domain_entry_group));
1192     else
1193         s->browse_domain_entry_group = avahi_s_entry_group_new(s, NULL, NULL);
1194
1195     if (!s->browse_domain_entry_group) {
1196         avahi_log_warn("Failed to create browse domain entry group: %s", avahi_strerror(s->error));
1197         return;
1198     }
1199
1200     if (avahi_server_add_ptr(s, s->browse_domain_entry_group, AVAHI_IF_UNSPEC, AVAHI_PROTO_UNSPEC, 0, AVAHI_DEFAULT_TTL, "b._dns-sd._udp.local", s->domain_name) < 0) {
1201         avahi_log_warn("Failed to add browse domain RR: %s", avahi_strerror(s->error));
1202         return;
1203     }
1204
1205     if (avahi_s_entry_group_commit(s->browse_domain_entry_group) < 0)
1206         avahi_log_warn("Failed to commit browse domain entry group: %s", avahi_strerror(s->error));
1207 }
1208
1209 static void register_stuff(AvahiServer *s) {
1210     assert(s);
1211
1212     server_set_state(s, AVAHI_SERVER_REGISTERING);
1213     s->n_host_rr_pending ++; /** Make sure that the state isn't changed tp AVAHI_SERVER_RUNNING too early */
1214
1215     register_hinfo(s);
1216     register_browse_domain(s);
1217     avahi_interface_monitor_update_rrs(s->monitor, 0);
1218
1219     s->n_host_rr_pending --;
1220
1221     if (s->n_host_rr_pending == 0)
1222         server_set_state(s, AVAHI_SERVER_RUNNING);
1223 }
1224
1225 static void update_fqdn(AvahiServer *s) {
1226     char *n;
1227
1228     assert(s);
1229     assert(s->host_name);
1230     assert(s->domain_name);
1231
1232     if (!(n = avahi_strdup_printf("%s.%s", s->host_name, s->domain_name)))
1233         return; /* OOM */
1234
1235     avahi_free(s->host_name_fqdn);
1236     s->host_name_fqdn = n;
1237 }
1238
1239 int avahi_server_set_host_name(AvahiServer *s, const char *host_name) {
1240     char *hn = NULL;
1241     assert(s);
1242
1243     AVAHI_CHECK_VALIDITY(s, !host_name || avahi_is_valid_host_name(host_name), AVAHI_ERR_INVALID_HOST_NAME);
1244
1245     if (!host_name) {
1246         hn = avahi_get_host_name_strdup();
1247         hn[strcspn(hn, ".")] = 0;
1248         host_name = hn;
1249     }
1250
1251     if (avahi_domain_equal(s->host_name, host_name) && s->state != AVAHI_SERVER_COLLISION) {
1252         avahi_free(hn);
1253         return avahi_server_set_errno(s, AVAHI_ERR_NO_CHANGE);
1254     }
1255
1256     withdraw_host_rrs(s);
1257
1258     avahi_free(s->host_name);
1259     s->host_name = hn ? hn : avahi_strdup(host_name);
1260
1261     update_fqdn(s);
1262
1263     register_stuff(s);
1264     return AVAHI_OK;
1265 }
1266
1267 int avahi_server_set_domain_name(AvahiServer *s, const char *domain_name) {
1268     char *dn = NULL;
1269     assert(s);
1270
1271     AVAHI_CHECK_VALIDITY(s, !domain_name || avahi_is_valid_domain_name(domain_name), AVAHI_ERR_INVALID_DOMAIN_NAME);
1272
1273     if (!domain_name) {
1274         dn = avahi_strdup("local");
1275         domain_name = dn;
1276     }
1277
1278     if (avahi_domain_equal(s->domain_name, domain_name)) {
1279         avahi_free(dn);
1280         return avahi_server_set_errno(s, AVAHI_ERR_NO_CHANGE);
1281     }
1282
1283     withdraw_host_rrs(s);
1284
1285     avahi_free(s->domain_name);
1286     s->domain_name = avahi_normalize_name_strdup(domain_name);
1287     update_fqdn(s);
1288
1289     register_stuff(s);
1290
1291     avahi_free(dn);
1292     return AVAHI_OK;
1293 }
1294
1295 static int valid_server_config(const AvahiServerConfig *sc) {
1296     AvahiStringList *l;
1297
1298     assert(sc);
1299
1300     if (sc->n_wide_area_servers > AVAHI_WIDE_AREA_SERVERS_MAX)
1301         return AVAHI_ERR_INVALID_CONFIG;
1302
1303     if (sc->host_name && !avahi_is_valid_host_name(sc->host_name))
1304         return AVAHI_ERR_INVALID_HOST_NAME;
1305
1306     if (sc->domain_name && !avahi_is_valid_domain_name(sc->domain_name))
1307         return AVAHI_ERR_INVALID_DOMAIN_NAME;
1308
1309     for (l = sc->browse_domains; l; l = l->next)
1310         if (!avahi_is_valid_domain_name((char*) l->text))
1311             return AVAHI_ERR_INVALID_DOMAIN_NAME;
1312
1313     return AVAHI_OK;
1314 }
1315
1316 static int setup_sockets(AvahiServer *s) {
1317     assert(s);
1318
1319     s->fd_ipv4 = s->config.use_ipv4 ? avahi_open_socket_ipv4(s->config.disallow_other_stacks) : -1;
1320     s->fd_ipv6 = s->config.use_ipv6 ? avahi_open_socket_ipv6(s->config.disallow_other_stacks) : -1;
1321
1322     if (s->fd_ipv6 < 0 && s->fd_ipv4 < 0)
1323         return AVAHI_ERR_NO_NETWORK;
1324
1325     if (s->fd_ipv4 < 0 && s->config.use_ipv4)
1326         avahi_log_notice("Failed to create IPv4 socket, proceeding in IPv6 only mode");
1327     else if (s->fd_ipv6 < 0 && s->config.use_ipv6)
1328         avahi_log_notice("Failed to create IPv6 socket, proceeding in IPv4 only mode");
1329
1330     s->fd_legacy_unicast_ipv4 = s->fd_ipv4 >= 0 && s->config.enable_reflector ? avahi_open_unicast_socket_ipv4() : -1;
1331     s->fd_legacy_unicast_ipv6 = s->fd_ipv6 >= 0 && s->config.enable_reflector ? avahi_open_unicast_socket_ipv6() : -1;
1332
1333     s->watch_ipv4 =
1334         s->watch_ipv6 =
1335         s->watch_legacy_unicast_ipv4 =
1336         s->watch_legacy_unicast_ipv6 = NULL;
1337
1338     if (s->fd_ipv4 >= 0)
1339         s->watch_ipv4 = s->poll_api->watch_new(s->poll_api, s->fd_ipv4, AVAHI_WATCH_IN, mcast_socket_event, s);
1340     if (s->fd_ipv6 >= 0)
1341         s->watch_ipv6 = s->poll_api->watch_new(s->poll_api, s->fd_ipv6, AVAHI_WATCH_IN, mcast_socket_event, s);
1342
1343     if (s->fd_legacy_unicast_ipv4 >= 0)
1344         s->watch_legacy_unicast_ipv4 = s->poll_api->watch_new(s->poll_api, s->fd_legacy_unicast_ipv4, AVAHI_WATCH_IN, legacy_unicast_socket_event, s);
1345     if (s->fd_legacy_unicast_ipv6 >= 0)
1346         s->watch_legacy_unicast_ipv6 = s->poll_api->watch_new(s->poll_api, s->fd_legacy_unicast_ipv6, AVAHI_WATCH_IN, legacy_unicast_socket_event, s);
1347
1348     return 0;
1349 }
1350
1351 AvahiServer *avahi_server_new(const AvahiPoll *poll_api, const AvahiServerConfig *sc, AvahiServerCallback callback, void* userdata, int *error) {
1352     AvahiServer *s;
1353     int e;
1354
1355     if (sc && (e = valid_server_config(sc)) < 0) {
1356         if (error)
1357             *error = e;
1358         return NULL;
1359     }
1360
1361     if (!(s = avahi_new(AvahiServer, 1))) {
1362         if (error)
1363             *error = AVAHI_ERR_NO_MEMORY;
1364
1365         return NULL;
1366     }
1367
1368     s->poll_api = poll_api;
1369
1370     if (sc)
1371         avahi_server_config_copy(&s->config, sc);
1372     else
1373         avahi_server_config_init(&s->config);
1374
1375     if ((e = setup_sockets(s)) < 0) {
1376         if (error)
1377             *error = e;
1378
1379         avahi_server_config_free(&s->config);
1380         avahi_free(s);
1381
1382         return NULL;
1383     }
1384
1385     s->n_host_rr_pending = 0;
1386     s->need_entry_cleanup = 0;
1387     s->need_group_cleanup = 0;
1388     s->need_browser_cleanup = 0;
1389     s->hinfo_entry_group = NULL;
1390     s->browse_domain_entry_group = NULL;
1391     s->error = AVAHI_OK;
1392     s->state = AVAHI_SERVER_INVALID;
1393
1394     s->callback = callback;
1395     s->userdata = userdata;
1396
1397     s->time_event_queue = avahi_time_event_queue_new(poll_api);
1398
1399     s->entries_by_key = avahi_hashmap_new((AvahiHashFunc) avahi_key_hash, (AvahiEqualFunc) avahi_key_equal, NULL, NULL);
1400     AVAHI_LLIST_HEAD_INIT(AvahiEntry, s->entries);
1401     AVAHI_LLIST_HEAD_INIT(AvahiGroup, s->groups);
1402
1403     s->record_browser_hashmap = avahi_hashmap_new((AvahiHashFunc) avahi_key_hash, (AvahiEqualFunc) avahi_key_equal, NULL, NULL);
1404     AVAHI_LLIST_HEAD_INIT(AvahiSRecordBrowser, s->record_browsers);
1405     AVAHI_LLIST_HEAD_INIT(AvahiSHostNameResolver, s->host_name_resolvers);
1406     AVAHI_LLIST_HEAD_INIT(AvahiSAddressResolver, s->address_resolvers);
1407     AVAHI_LLIST_HEAD_INIT(AvahiSDomainBrowser, s->domain_browsers);
1408     AVAHI_LLIST_HEAD_INIT(AvahiSServiceTypeBrowser, s->service_type_browsers);
1409     AVAHI_LLIST_HEAD_INIT(AvahiSServiceBrowser, s->service_browsers);
1410     AVAHI_LLIST_HEAD_INIT(AvahiSServiceResolver, s->service_resolvers);
1411     AVAHI_LLIST_HEAD_INIT(AvahiSDNSServerBrowser, s->dns_server_browsers);
1412
1413     s->legacy_unicast_reflect_slots = NULL;
1414     s->legacy_unicast_reflect_id = 0;
1415
1416     s->record_list = avahi_record_list_new();
1417
1418     /* Get host name */
1419     s->host_name = s->config.host_name ? avahi_normalize_name_strdup(s->config.host_name) : avahi_get_host_name_strdup();
1420     s->host_name[strcspn(s->host_name, ".")] = 0;
1421     s->domain_name = s->config.domain_name ? avahi_normalize_name_strdup(s->config.domain_name) : avahi_strdup("local");
1422     s->host_name_fqdn = NULL;
1423     update_fqdn(s);
1424
1425     do {
1426         s->local_service_cookie = (uint32_t) rand() * (uint32_t) rand();
1427     } while (s->local_service_cookie == AVAHI_SERVICE_COOKIE_INVALID);
1428
1429     if (s->config.enable_wide_area) {
1430         s->wide_area_lookup_engine = avahi_wide_area_engine_new(s);
1431         avahi_wide_area_set_servers(s->wide_area_lookup_engine, s->config.wide_area_servers, s->config.n_wide_area_servers);
1432     } else
1433         s->wide_area_lookup_engine = NULL;
1434
1435     s->multicast_lookup_engine = avahi_multicast_lookup_engine_new(s);
1436
1437     s->monitor = avahi_interface_monitor_new(s);
1438     avahi_interface_monitor_sync(s->monitor);
1439
1440     register_localhost(s);
1441     register_stuff(s);
1442
1443     return s;
1444 }
1445
1446 void avahi_server_free(AvahiServer* s) {
1447     assert(s);
1448
1449     /* Remove all browsers */
1450
1451     while (s->dns_server_browsers)
1452         avahi_s_dns_server_browser_free(s->dns_server_browsers);
1453     while (s->host_name_resolvers)
1454         avahi_s_host_name_resolver_free(s->host_name_resolvers);
1455     while (s->address_resolvers)
1456         avahi_s_address_resolver_free(s->address_resolvers);
1457     while (s->domain_browsers)
1458         avahi_s_domain_browser_free(s->domain_browsers);
1459     while (s->service_type_browsers)
1460         avahi_s_service_type_browser_free(s->service_type_browsers);
1461     while (s->service_browsers)
1462         avahi_s_service_browser_free(s->service_browsers);
1463     while (s->service_resolvers)
1464         avahi_s_service_resolver_free(s->service_resolvers);
1465     while (s->record_browsers)
1466         avahi_s_record_browser_destroy(s->record_browsers);
1467
1468     /* Remove all locally rgeistered stuff */
1469
1470     while(s->entries)
1471         avahi_entry_free(s, s->entries);
1472
1473     avahi_interface_monitor_free(s->monitor);
1474
1475     while (s->groups)
1476         avahi_entry_group_free(s, s->groups);
1477
1478     free_slots(s);
1479
1480     avahi_hashmap_free(s->entries_by_key);
1481     avahi_record_list_free(s->record_list);
1482     avahi_hashmap_free(s->record_browser_hashmap);
1483
1484     if (s->wide_area_lookup_engine)
1485         avahi_wide_area_engine_free(s->wide_area_lookup_engine);
1486     avahi_multicast_lookup_engine_free(s->multicast_lookup_engine);
1487
1488     avahi_time_event_queue_free(s->time_event_queue);
1489
1490     /* Free watches */
1491
1492     if (s->watch_ipv4)
1493         s->poll_api->watch_free(s->watch_ipv4);
1494     if (s->watch_ipv6)
1495         s->poll_api->watch_free(s->watch_ipv6);
1496
1497     if (s->watch_legacy_unicast_ipv4)
1498         s->poll_api->watch_free(s->watch_legacy_unicast_ipv4);
1499     if (s->watch_legacy_unicast_ipv6)
1500         s->poll_api->watch_free(s->watch_legacy_unicast_ipv6);
1501
1502     /* Free sockets */
1503
1504     if (s->fd_ipv4 >= 0)
1505         close(s->fd_ipv4);
1506     if (s->fd_ipv6 >= 0)
1507         close(s->fd_ipv6);
1508
1509     if (s->fd_legacy_unicast_ipv4 >= 0)
1510         close(s->fd_legacy_unicast_ipv4);
1511     if (s->fd_legacy_unicast_ipv6 >= 0)
1512         close(s->fd_legacy_unicast_ipv6);
1513
1514     /* Free other stuff */
1515
1516     avahi_free(s->host_name);
1517     avahi_free(s->domain_name);
1518     avahi_free(s->host_name_fqdn);
1519
1520     avahi_server_config_free(&s->config);
1521
1522     avahi_free(s);
1523 }
1524
1525 const char* avahi_server_get_domain_name(AvahiServer *s) {
1526     assert(s);
1527
1528     return s->domain_name;
1529 }
1530
1531 const char* avahi_server_get_host_name(AvahiServer *s) {
1532     assert(s);
1533
1534     return s->host_name;
1535 }
1536
1537 const char* avahi_server_get_host_name_fqdn(AvahiServer *s) {
1538     assert(s);
1539
1540     return s->host_name_fqdn;
1541 }
1542
1543 void* avahi_server_get_data(AvahiServer *s) {
1544     assert(s);
1545
1546     return s->userdata;
1547 }
1548
1549 void avahi_server_set_data(AvahiServer *s, void* userdata) {
1550     assert(s);
1551
1552     s->userdata = userdata;
1553 }
1554
1555 AvahiServerState avahi_server_get_state(AvahiServer *s) {
1556     assert(s);
1557
1558     return s->state;
1559 }
1560
1561 AvahiServerConfig* avahi_server_config_init(AvahiServerConfig *c) {
1562     assert(c);
1563
1564     memset(c, 0, sizeof(AvahiServerConfig));
1565     c->use_ipv6 = 1;
1566     c->use_ipv4 = 1;
1567     c->allow_interfaces = NULL;
1568     c->deny_interfaces = NULL;
1569     c->host_name = NULL;
1570     c->domain_name = NULL;
1571     c->check_response_ttl = 0;
1572     c->publish_hinfo = 1;
1573     c->publish_addresses = 1;
1574     c->publish_workstation = 1;
1575     c->publish_domain = 1;
1576     c->use_iff_running = 0;
1577     c->enable_reflector = 0;
1578     c->reflect_ipv = 0;
1579     c->add_service_cookie = 0;
1580     c->enable_wide_area = 0;
1581     c->n_wide_area_servers = 0;
1582     c->disallow_other_stacks = 0;
1583     c->browse_domains = NULL;
1584     c->disable_publishing = 0;
1585     c->allow_point_to_point = 0;
1586     c->publish_aaaa_on_ipv4 = 1;
1587     c->publish_a_on_ipv6 = 0;
1588     c->n_cache_entries_max = AVAHI_DEFAULT_CACHE_ENTRIES_MAX;
1589
1590     return c;
1591 }
1592
1593 void avahi_server_config_free(AvahiServerConfig *c) {
1594     assert(c);
1595
1596     avahi_free(c->host_name);
1597     avahi_free(c->domain_name);
1598     avahi_string_list_free(c->browse_domains);
1599     avahi_string_list_free(c->allow_interfaces);
1600     avahi_string_list_free(c->deny_interfaces);
1601 }
1602
1603 AvahiServerConfig* avahi_server_config_copy(AvahiServerConfig *ret, const AvahiServerConfig *c) {
1604     char *d = NULL, *h = NULL;
1605     AvahiStringList *browse = NULL, *allow = NULL, *deny = NULL;
1606     assert(ret);
1607     assert(c);
1608
1609     if (c->host_name)
1610         if (!(h = avahi_strdup(c->host_name)))
1611             return NULL;
1612
1613     if (c->domain_name)
1614         if (!(d = avahi_strdup(c->domain_name))) {
1615             avahi_free(h);
1616             return NULL;
1617         }
1618
1619     if (!(browse = avahi_string_list_copy(c->browse_domains)) && c->browse_domains) {
1620         avahi_free(h);
1621         avahi_free(d);
1622         return NULL;
1623     }
1624
1625     if (!(allow = avahi_string_list_copy(c->allow_interfaces)) && c->allow_interfaces) {
1626         avahi_string_list_free(browse);
1627         avahi_free(h);
1628         avahi_free(d);
1629         return NULL;
1630     }
1631
1632     if (!(deny = avahi_string_list_copy(c->deny_interfaces)) && c->deny_interfaces) {
1633         avahi_string_list_free(allow);
1634         avahi_string_list_free(browse);
1635         avahi_free(h);
1636         avahi_free(d);
1637         return NULL;
1638     }
1639
1640     *ret = *c;
1641     ret->host_name = h;
1642     ret->domain_name = d;
1643     ret->browse_domains = browse;
1644     ret->allow_interfaces = allow;
1645     ret->deny_interfaces = deny;
1646
1647     return ret;
1648 }
1649
1650 int avahi_server_errno(AvahiServer *s) {
1651     assert(s);
1652
1653     return s->error;
1654 }
1655
1656 /* Just for internal use */
1657 int avahi_server_set_errno(AvahiServer *s, int error) {
1658     assert(s);
1659
1660     return s->error = error;
1661 }
1662
1663 uint32_t avahi_server_get_local_service_cookie(AvahiServer *s) {
1664     assert(s);
1665
1666     return s->local_service_cookie;
1667 }
1668
1669 static AvahiEntry *find_entry(AvahiServer *s, AvahiIfIndex interface, AvahiProtocol protocol, AvahiKey *key) {
1670     AvahiEntry *e;
1671
1672     assert(s);
1673     assert(key);
1674
1675     for (e = avahi_hashmap_lookup(s->entries_by_key, key); e; e = e->by_key_next)
1676
1677         if ((e->interface == interface || e->interface <= 0 || interface <= 0) &&
1678             (e->protocol == protocol || e->protocol == AVAHI_PROTO_UNSPEC || protocol == AVAHI_PROTO_UNSPEC) &&
1679             (!e->group || e->group->state == AVAHI_ENTRY_GROUP_ESTABLISHED || e->group->state == AVAHI_ENTRY_GROUP_REGISTERING))
1680
1681             return e;
1682
1683     return NULL;
1684 }
1685
1686 int avahi_server_get_group_of_service(AvahiServer *s, AvahiIfIndex interface, AvahiProtocol protocol, const char *name, const char *type, const char *domain, AvahiSEntryGroup** ret_group) {
1687     AvahiKey *key = NULL;
1688     AvahiEntry *e;
1689     int ret;
1690     char n[AVAHI_DOMAIN_NAME_MAX];
1691
1692     assert(s);
1693     assert(name);
1694     assert(type);
1695     assert(ret_group);
1696
1697     AVAHI_CHECK_VALIDITY(s, AVAHI_IF_VALID(interface), AVAHI_ERR_INVALID_INTERFACE);
1698     AVAHI_CHECK_VALIDITY(s, AVAHI_PROTO_VALID(protocol), AVAHI_ERR_INVALID_PROTOCOL);
1699     AVAHI_CHECK_VALIDITY(s, avahi_is_valid_service_name(name), AVAHI_ERR_INVALID_SERVICE_NAME);
1700     AVAHI_CHECK_VALIDITY(s, avahi_is_valid_service_type_strict(type), AVAHI_ERR_INVALID_SERVICE_TYPE);
1701     AVAHI_CHECK_VALIDITY(s, !domain || avahi_is_valid_domain_name(domain), AVAHI_ERR_INVALID_DOMAIN_NAME);
1702
1703     if ((ret = avahi_service_name_join(n, sizeof(n), name, type, domain) < 0))
1704         return avahi_server_set_errno(s, ret);
1705
1706     if (!(key = avahi_key_new(n, AVAHI_DNS_CLASS_IN, AVAHI_DNS_TYPE_SRV)))
1707         return avahi_server_set_errno(s, AVAHI_ERR_NO_MEMORY);
1708
1709     e = find_entry(s, interface, protocol, key);
1710     avahi_key_unref(key);
1711
1712     if (e) {
1713         *ret_group = e->group;
1714         return AVAHI_OK;
1715     }
1716
1717     return avahi_server_set_errno(s, AVAHI_ERR_NOT_FOUND);
1718 }
1719
1720 int avahi_server_is_service_local(AvahiServer *s, AvahiIfIndex interface, AvahiProtocol protocol, const char *name) {
1721     AvahiKey *key = NULL;
1722     AvahiEntry *e;
1723
1724     assert(s);
1725     assert(name);
1726
1727     if (!s->host_name_fqdn)
1728         return 0;
1729
1730     if (!(key = avahi_key_new(name, AVAHI_DNS_CLASS_IN, AVAHI_DNS_TYPE_SRV)))
1731         return 0;
1732
1733     e = find_entry(s, interface, protocol, key);
1734     avahi_key_unref(key);
1735
1736     if (!e)
1737         return 0;
1738
1739     return avahi_domain_equal(s->host_name_fqdn, e->record->data.srv.name);
1740 }
1741
1742 int avahi_server_is_record_local(AvahiServer *s, AvahiIfIndex interface, AvahiProtocol protocol, AvahiRecord *record) {
1743     AvahiEntry *e;
1744
1745     assert(s);
1746     assert(record);
1747
1748     for (e = avahi_hashmap_lookup(s->entries_by_key, record->key); e; e = e->by_key_next)
1749
1750         if ((e->interface == interface || e->interface <= 0 || interface <= 0) &&
1751             (e->protocol == protocol || e->protocol == AVAHI_PROTO_UNSPEC || protocol == AVAHI_PROTO_UNSPEC) &&
1752             (!e->group || e->group->state == AVAHI_ENTRY_GROUP_ESTABLISHED || e->group->state == AVAHI_ENTRY_GROUP_REGISTERING) &&
1753             avahi_record_equal_no_ttl(record, e->record))
1754             return 1;
1755
1756     return 0;
1757 }
1758
1759 /** Set the wide area DNS servers */
1760 int avahi_server_set_wide_area_servers(AvahiServer *s, const AvahiAddress *a, unsigned n) {
1761     assert(s);
1762
1763     if (!s->wide_area_lookup_engine)
1764         return avahi_server_set_errno(s, AVAHI_ERR_INVALID_CONFIG);
1765
1766     avahi_wide_area_set_servers(s->wide_area_lookup_engine, a, n);
1767     return AVAHI_OK;
1768 }
1769
1770 const AvahiServerConfig* avahi_server_get_config(AvahiServer *s) {
1771     assert(s);
1772
1773     return &s->config;
1774 }
1775
1776 /** Set the browsing domains */
1777 int avahi_server_set_browse_domains(AvahiServer *s, AvahiStringList *domains) {
1778     AvahiStringList *l;
1779
1780     assert(s);
1781
1782     for (l = s->config.browse_domains; l; l = l->next)
1783         if (!avahi_is_valid_domain_name((char*) l->text))
1784             return avahi_server_set_errno(s, AVAHI_ERR_INVALID_DOMAIN_NAME);
1785
1786     avahi_string_list_free(s->config.browse_domains);
1787     s->config.browse_domains = avahi_string_list_copy(domains);
1788
1789     return AVAHI_OK;
1790 }