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

   1 /* $Id$ */
   2
   3 /***
   4   This file is part of avahi.
   5
   6   avahi is free software; you can redistribute it and/or modify it
   7   under the terms of the GNU Lesser General Public License as
   8   published by the Free Software Foundation; either version 2.1 of the
   9   License, or (at your option) any later version.
  10
  11   avahi is distributed in the hope that it will be useful, but WITHOUT
  12   ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  13   or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General
  14   Public License for more details.
  15
  16   You should have received a copy of the GNU Lesser General Public
  17   License along with avahi; if not, write to the Free Software
  18   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
  19   USA.
  20 ***/
  21
  22 #ifdef HAVE_CONFIG_H
  23 #include <config.h>
  24 #endif
  25
  26 #include <sys/types.h>
  27 #include <sys/socket.h>
  28 #include <netinet/in.h>
  29 #include <arpa/inet.h>
  30 #include <string.h>
  31 #include <sys/utsname.h>
  32 #include <unistd.h>
  33 #include <errno.h>
  34 #include <stdio.h>
  35 #include <assert.h>
  36 #include <stdlib.h>
  37
  38 #include <avahi-common/domain.h>
  39 #include <avahi-common/timeval.h>
  40 #include <avahi-common/malloc.h>
  41 #include <avahi-common/error.h>
  42
  43 #include "internal.h"
  44 #include "iface.h"
  45 #include "socket.h"
  46 #include "browse.h"
  47 #include "log.h"
  48 #include "util.h"
  49 #include "dns-srv-rr.h"
  50 #include "addr-util.h"
  51 #include "domain-util.h"
  52 #include "rr-util.h"
  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 /*         char *txt; */
 663
 664         if (!(record = avahi_dns_packet_consume_record(p, &cache_flush))) {
 665             avahi_log_warn(__FILE__": Packet too short or invalid while reading response record. (Maybe a UTF-8 problem?)");
 666             break;
 667         }
 668
 669         if (!avahi_key_is_pattern(record->key) && !avahi_record_is_link_local_address(record)) {
 670
 671             if (handle_conflict(s, i, record, cache_flush)) {
 672                 if (!from_local_iface)
 673                     reflect_response(s, i, record, cache_flush);
 674                 avahi_cache_update(i->cache, record, cache_flush, a);
 675                 avahi_response_scheduler_incoming(i->response_scheduler, record, cache_flush);
 676             }
 677         }
 678
 679         avahi_record_unref(record);
 680     }
 681
 682     /* If the incoming response contained a conflicting record, some
 683        records have been scheduling for sending. We need to flush them
 684        here. */
 685     if (!avahi_record_list_is_empty(s->record_list))
 686         avahi_server_generate_response(s, i, NULL, NULL, 0, 0, 1);
 687 }
 688
 689 static AvahiLegacyUnicastReflectSlot* allocate_slot(AvahiServer *s) {
 690     unsigned n, idx = (unsigned) -1;
 691     AvahiLegacyUnicastReflectSlot *slot;
 692
 693     assert(s);
 694
 695     if (!s->legacy_unicast_reflect_slots)
 696         s->legacy_unicast_reflect_slots = avahi_new0(AvahiLegacyUnicastReflectSlot*, AVAHI_LEGACY_UNICAST_REFLECT_SLOTS_MAX);
 697
 698     for (n = 0; n < AVAHI_LEGACY_UNICAST_REFLECT_SLOTS_MAX; n++, s->legacy_unicast_reflect_id++) {
 699         idx = s->legacy_unicast_reflect_id % AVAHI_LEGACY_UNICAST_REFLECT_SLOTS_MAX;
 700
 701         if (!s->legacy_unicast_reflect_slots[idx])
 702             break;
 703     }
 704
 705     if (idx == (unsigned) -1 || s->legacy_unicast_reflect_slots[idx])
 706         return NULL;
 707
 708     if (!(slot = avahi_new(AvahiLegacyUnicastReflectSlot, 1)))
 709         return NULL; /* OOM */
 710
 711     s->legacy_unicast_reflect_slots[idx] = slot;
 712     slot->id = s->legacy_unicast_reflect_id++;
 713     slot->server = s;
 714
 715     return slot;
 716 }
 717
 718 static void deallocate_slot(AvahiServer *s, AvahiLegacyUnicastReflectSlot *slot) {
 719     unsigned idx;
 720
 721     assert(s);
 722     assert(slot);
 723
 724     idx = slot->id % AVAHI_LEGACY_UNICAST_REFLECT_SLOTS_MAX;
 725
 726     assert(s->legacy_unicast_reflect_slots[idx] == slot);
 727
 728     avahi_time_event_free(slot->time_event);
 729
 730     avahi_free(slot);
 731     s->legacy_unicast_reflect_slots[idx] = NULL;
 732 }
 733
 734 static void free_slots(AvahiServer *s) {
 735     unsigned idx;
 736     assert(s);
 737
 738     if (!s->legacy_unicast_reflect_slots)
 739         return;
 740
 741     for (idx = 0; idx < AVAHI_LEGACY_UNICAST_REFLECT_SLOTS_MAX; idx ++)
 742         if (s->legacy_unicast_reflect_slots[idx])
 743             deallocate_slot(s, s->legacy_unicast_reflect_slots[idx]);
 744
 745     avahi_free(s->legacy_unicast_reflect_slots);
 746     s->legacy_unicast_reflect_slots = NULL;
 747 }
 748
 749 static AvahiLegacyUnicastReflectSlot* find_slot(AvahiServer *s, uint16_t id) {
 750     unsigned idx;
 751
 752     assert(s);
 753
 754     if (!s->legacy_unicast_reflect_slots)
 755         return NULL;
 756
 757     idx = id % AVAHI_LEGACY_UNICAST_REFLECT_SLOTS_MAX;
 758
 759     if (!s->legacy_unicast_reflect_slots[idx] || s->legacy_unicast_reflect_slots[idx]->id != id)
 760         return NULL;
 761
 762     return s->legacy_unicast_reflect_slots[idx];
 763 }
 764
 765 static void legacy_unicast_reflect_slot_timeout(AvahiTimeEvent *e, void *userdata) {
 766     AvahiLegacyUnicastReflectSlot *slot = userdata;
 767
 768     assert(e);
 769     assert(slot);
 770     assert(slot->time_event == e);
 771
 772     deallocate_slot(slot->server, slot);
 773 }
 774
 775 static void reflect_legacy_unicast_query_packet(AvahiServer *s, AvahiDnsPacket *p, AvahiInterface *i, const AvahiAddress *a, uint16_t port) {
 776     AvahiLegacyUnicastReflectSlot *slot;
 777     AvahiInterface *j;
 778
 779     assert(s);
 780     assert(p);
 781     assert(i);
 782     assert(a);
 783     assert(port > 0);
 784     assert(i->protocol == a->proto);
 785
 786     if (!s->config.enable_reflector)
 787         return;
 788
 789     /* Reflecting legacy unicast queries is a little more complicated
 790        than reflecting normal queries, since we must route the
 791        responses back to the right client. Therefore we must store
 792        some information for finding the right client contact data for
 793        response packets. In contrast to normal queries legacy
 794        unicast query and response packets are reflected untouched and
 795        are not reassembled into larger packets */
 796
 797     if (!(slot = allocate_slot(s))) {
 798         /* No slot available, we drop this legacy unicast query */
 799         avahi_log_warn("No slot available for legacy unicast reflection, dropping query packet.");
 800         return;
 801     }
 802
 803     slot->original_id = avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_ID);
 804     slot->address = *a;
 805     slot->port = port;
 806     slot->interface = i->hardware->index;
 807
 808     avahi_elapse_time(&slot->elapse_time, 2000, 0);
 809     slot->time_event = avahi_time_event_new(s->time_event_queue, &slot->elapse_time, legacy_unicast_reflect_slot_timeout, slot);
 810
 811     /* Patch the packet with our new locally generatet id */
 812     avahi_dns_packet_set_field(p, AVAHI_DNS_FIELD_ID, slot->id);
 813
 814     for (j = s->monitor->interfaces; j; j = j->interface_next)
 815         if (j->announcing &&
 816             j != i &&
 817             (s->config.reflect_ipv || j->protocol == i->protocol)) {
 818
 819             if (j->protocol == AVAHI_PROTO_INET && s->fd_legacy_unicast_ipv4 >= 0) {
 820                 avahi_send_dns_packet_ipv4(s->fd_legacy_unicast_ipv4, j->hardware->index, p, NULL, NULL, 0);
 821             } else if (j->protocol == AVAHI_PROTO_INET6 && s->fd_legacy_unicast_ipv6 >= 0)
 822                 avahi_send_dns_packet_ipv6(s->fd_legacy_unicast_ipv6, j->hardware->index, p, NULL, NULL, 0);
 823         }
 824
 825     /* Reset the id */
 826     avahi_dns_packet_set_field(p, AVAHI_DNS_FIELD_ID, slot->original_id);
 827 }
 828
 829 static int originates_from_local_legacy_unicast_socket(AvahiServer *s, const AvahiAddress *address, uint16_t port) {
 830     assert(s);
 831     assert(address);
 832     assert(port > 0);
 833
 834     if (!s->config.enable_reflector)
 835         return 0;
 836
 837     if (!avahi_address_is_local(s->monitor, address))
 838         return 0;
 839
 840     if (address->proto == AVAHI_PROTO_INET && s->fd_legacy_unicast_ipv4 >= 0) {
 841         struct sockaddr_in lsa;
 842         socklen_t l = sizeof(lsa);
 843
 844         if (getsockname(s->fd_legacy_unicast_ipv4, (struct sockaddr*) &lsa, &l) != 0)
 845             avahi_log_warn("getsockname(): %s", strerror(errno));
 846         else
 847             return avahi_port_from_sockaddr((struct sockaddr*) &lsa) == port;
 848
 849     }
 850
 851     if (address->proto == AVAHI_PROTO_INET6 && s->fd_legacy_unicast_ipv6 >= 0) {
 852         struct sockaddr_in6 lsa;
 853         socklen_t l = sizeof(lsa);
 854
 855         if (getsockname(s->fd_legacy_unicast_ipv6, (struct sockaddr*) &lsa, &l) != 0)
 856             avahi_log_warn("getsockname(): %s", strerror(errno));
 857         else
 858             return avahi_port_from_sockaddr((struct sockaddr*) &lsa) == port;
 859     }
 860
 861     return 0;
 862 }
 863
 864 static int is_mdns_mcast_address(const AvahiAddress *a) {
 865     AvahiAddress b;
 866     assert(a);
 867
 868     avahi_address_parse(a->proto == AVAHI_PROTO_INET ? AVAHI_IPV4_MCAST_GROUP : AVAHI_IPV6_MCAST_GROUP, a->proto, &b);
 869     return avahi_address_cmp(a, &b) == 0;
 870 }
 871
 872 static int originates_from_local_iface(AvahiServer *s, AvahiIfIndex iface, const AvahiAddress *a, uint16_t port) {
 873     assert(s);
 874     assert(iface != AVAHI_IF_UNSPEC);
 875     assert(a);
 876
 877     /* If it isn't the MDNS port it can't be generated by us */
 878     if (port != AVAHI_MDNS_PORT)
 879         return 0;
 880
 881     return avahi_interface_has_address(s->monitor, iface, a);
 882 }
 883
 884 static void dispatch_packet(AvahiServer *s, AvahiDnsPacket *p, const AvahiAddress *src_address, uint16_t port, const AvahiAddress *dst_address, AvahiIfIndex iface, int ttl) {
 885     AvahiInterface *i;
 886     int from_local_iface = 0;
 887
 888     assert(s);
 889     assert(p);
 890     assert(src_address);
 891     assert(dst_address);
 892     assert(iface > 0);
 893     assert(src_address->proto == dst_address->proto);
 894
 895     if (!(i = avahi_interface_monitor_get_interface(s->monitor, iface, src_address->proto)) ||
 896         !i->announcing) {
 897         avahi_log_warn("Received packet from invalid interface.");
 898         return;
 899     }
 900
 901     if (port <= 0) {
 902         /* This fixes RHBZ #475394 */
 903         avahi_log_warn("Received packet from invalid source port %u.", (unsigned) port);
 904         return;
 905     }
 906
 907     if (avahi_address_is_ipv4_in_ipv6(src_address))
 908         /* This is an IPv4 address encapsulated in IPv6, so let's ignore it. */
 909         return;
 910
 911     if (originates_from_local_legacy_unicast_socket(s, src_address, port))
 912         /* This originates from our local reflector, so let's ignore it */
 913         return;
 914
 915     /* We don't want to reflect local traffic, so we check if this packet is generated locally. */
 916     if (s->config.enable_reflector)
 917         from_local_iface = originates_from_local_iface(s, iface, src_address, port);
 918
 919     if (avahi_dns_packet_check_valid_multicast(p) < 0) {
 920         avahi_log_warn("Received invalid packet.");
 921         return;
 922     }
 923
 924     if (avahi_dns_packet_is_query(p)) {
 925         int legacy_unicast = 0;
 926
 927         if (avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_ARCOUNT) != 0) {
 928             avahi_log_warn("Invalid query packet.");
 929             return;
 930         }
 931
 932         if (port != AVAHI_MDNS_PORT) {
 933             /* Legacy Unicast */
 934
 935             if ((avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_ANCOUNT) != 0 ||
 936                  avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_NSCOUNT) != 0)) {
 937                 avahi_log_warn("Invalid legacy unicast query packet.");
 938                 return;
 939             }
 940
 941             legacy_unicast = 1;
 942         }
 943
 944         if (legacy_unicast)
 945             reflect_legacy_unicast_query_packet(s, p, i, src_address, port);
 946
 947         handle_query_packet(s, p, i, src_address, port, legacy_unicast, from_local_iface);
 948
 949     } else {
 950         char t[AVAHI_ADDRESS_STR_MAX];
 951
 952         if (port != AVAHI_MDNS_PORT) {
 953             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);
 954             return;
 955         }
 956
 957         if (ttl != 255 && s->config.check_response_ttl) {
 958             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);
 959             return;
 960         }
 961
 962         if (!is_mdns_mcast_address(dst_address) &&
 963             !avahi_interface_address_on_link(i, src_address)) {
 964
 965             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);
 966             return;
 967         }
 968
 969         if (avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_QDCOUNT) != 0 ||
 970             avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_ANCOUNT) == 0 ||
 971             avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_NSCOUNT) != 0) {
 972
 973             avahi_log_warn("Invalid response packet from host %s.", avahi_address_snprint(t, sizeof(t), src_address));
 974             return;
 975         }
 976
 977         handle_response_packet(s, p, i, src_address, from_local_iface);
 978     }
 979 }
 980
 981 static void dispatch_legacy_unicast_packet(AvahiServer *s, AvahiDnsPacket *p) {
 982     AvahiInterface *j;
 983     AvahiLegacyUnicastReflectSlot *slot;
 984
 985     assert(s);
 986     assert(p);
 987
 988     if (avahi_dns_packet_check_valid(p) < 0 || avahi_dns_packet_is_query(p)) {
 989         avahi_log_warn("Received invalid packet.");
 990         return;
 991     }
 992
 993     if (!(slot = find_slot(s, avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_ID)))) {
 994         avahi_log_warn("Received legacy unicast response with unknown id");
 995         return;
 996     }
 997
 998     if (!(j = avahi_interface_monitor_get_interface(s->monitor, slot->interface, slot->address.proto)) ||
 999         !j->announcing)
1000         return;
1001
1002     /* Patch the original ID into this response */
1003     avahi_dns_packet_set_field(p, AVAHI_DNS_FIELD_ID, slot->original_id);
1004
1005     /* Forward the response to the correct client */
1006     avahi_interface_send_packet_unicast(j, p, &slot->address, slot->port);
1007
1008     /* Undo changes to packet */
1009     avahi_dns_packet_set_field(p, AVAHI_DNS_FIELD_ID, slot->id);
1010 }
1011
1012 static void mcast_socket_event(AvahiWatch *w, int fd, AvahiWatchEvent events, void *userdata) {
1013     AvahiServer *s = userdata;
1014     AvahiAddress dest, src;
1015     AvahiDnsPacket *p = NULL;
1016     AvahiIfIndex iface;
1017     uint16_t port;
1018     uint8_t ttl;
1019
1020     assert(w);
1021     assert(fd >= 0);
1022     assert(events & AVAHI_WATCH_IN);
1023
1024     if (fd == s->fd_ipv4) {
1025         dest.proto = src.proto = AVAHI_PROTO_INET;
1026         p = avahi_recv_dns_packet_ipv4(s->fd_ipv4, &src.data.ipv4, &port, &dest.data.ipv4, &iface, &ttl);
1027     } else {
1028         assert(fd == s->fd_ipv6);
1029         dest.proto = src.proto = AVAHI_PROTO_INET6;
1030         p = avahi_recv_dns_packet_ipv6(s->fd_ipv6, &src.data.ipv6, &port, &dest.data.ipv6, &iface, &ttl);
1031     }
1032
1033     if (p) {
1034         if (iface == AVAHI_IF_UNSPEC)
1035             iface = avahi_find_interface_for_address(s->monitor, &dest);
1036
1037         if (iface != AVAHI_IF_UNSPEC)
1038             dispatch_packet(s, p, &src, port, &dest, iface, ttl);
1039         else
1040             avahi_log_error("Incoming packet received on address that isn't local.");
1041
1042         avahi_dns_packet_free(p);
1043
1044         avahi_cleanup_dead_entries(s);
1045     }
1046 }
1047
1048 static void legacy_unicast_socket_event(AvahiWatch *w, int fd, AvahiWatchEvent events, void *userdata) {
1049     AvahiServer *s = userdata;
1050     AvahiDnsPacket *p = NULL;
1051
1052     assert(w);
1053     assert(fd >= 0);
1054     assert(events & AVAHI_WATCH_IN);
1055
1056     if (fd == s->fd_legacy_unicast_ipv4)
1057         p = avahi_recv_dns_packet_ipv4(s->fd_legacy_unicast_ipv4, NULL, NULL, NULL, NULL, NULL);
1058     else {
1059         assert(fd == s->fd_legacy_unicast_ipv6);
1060         p = avahi_recv_dns_packet_ipv6(s->fd_legacy_unicast_ipv6, NULL, NULL, NULL, NULL, NULL);
1061     }
1062
1063     if (p) {
1064         dispatch_legacy_unicast_packet(s, p);
1065         avahi_dns_packet_free(p);
1066
1067         avahi_cleanup_dead_entries(s);
1068     }
1069 }
1070
1071 static void server_set_state(AvahiServer *s, AvahiServerState state) {
1072     assert(s);
1073
1074     if (s->state == state)
1075         return;
1076
1077     s->state = state;
1078
1079     avahi_interface_monitor_update_rrs(s->monitor, 0);
1080
1081     if (s->callback)
1082         s->callback(s, state, s->userdata);
1083 }
1084
1085 static void withdraw_host_rrs(AvahiServer *s) {
1086     assert(s);
1087
1088     if (s->hinfo_entry_group)
1089         avahi_s_entry_group_reset(s->hinfo_entry_group);
1090
1091     if (s->browse_domain_entry_group)
1092         avahi_s_entry_group_reset(s->browse_domain_entry_group);
1093
1094     avahi_interface_monitor_update_rrs(s->monitor, 1);
1095     s->n_host_rr_pending = 0;
1096 }
1097
1098 void avahi_server_decrease_host_rr_pending(AvahiServer *s) {
1099     assert(s);
1100
1101     assert(s->n_host_rr_pending > 0);
1102
1103     if (--s->n_host_rr_pending == 0)
1104         server_set_state(s, AVAHI_SERVER_RUNNING);
1105 }
1106
1107 void avahi_host_rr_entry_group_callback(AvahiServer *s, AvahiSEntryGroup *g, AvahiEntryGroupState state, AVAHI_GCC_UNUSED void *userdata) {
1108     assert(s);
1109     assert(g);
1110
1111     if (state == AVAHI_ENTRY_GROUP_REGISTERING &&
1112         s->state == AVAHI_SERVER_REGISTERING)
1113         s->n_host_rr_pending ++;
1114
1115     else if (state == AVAHI_ENTRY_GROUP_COLLISION &&
1116         (s->state == AVAHI_SERVER_REGISTERING || s->state == AVAHI_SERVER_RUNNING)) {
1117         withdraw_host_rrs(s);
1118         server_set_state(s, AVAHI_SERVER_COLLISION);
1119
1120     } else if (state == AVAHI_ENTRY_GROUP_ESTABLISHED &&
1121                s->state == AVAHI_SERVER_REGISTERING)
1122         avahi_server_decrease_host_rr_pending(s);
1123 }
1124
1125 static void register_hinfo(AvahiServer *s) {
1126     struct utsname utsname;
1127     AvahiRecord *r;
1128
1129     assert(s);
1130
1131     if (!s->config.publish_hinfo)
1132         return;
1133
1134     if (s->hinfo_entry_group)
1135         assert(avahi_s_entry_group_is_empty(s->hinfo_entry_group));
1136     else
1137         s->hinfo_entry_group = avahi_s_entry_group_new(s, avahi_host_rr_entry_group_callback, NULL);
1138
1139     if (!s->hinfo_entry_group) {
1140         avahi_log_warn("Failed to create HINFO entry group: %s", avahi_strerror(s->error));
1141         return;
1142     }
1143
1144     /* Fill in HINFO rr */
1145     if ((r = avahi_record_new_full(s->host_name_fqdn, AVAHI_DNS_CLASS_IN, AVAHI_DNS_TYPE_HINFO, AVAHI_DEFAULT_TTL_HOST_NAME))) {
1146
1147         if (uname(&utsname) < 0)
1148             avahi_log_warn("uname() failed: %s\n", avahi_strerror(errno));
1149         else {
1150
1151             r->data.hinfo.cpu = avahi_strdup(avahi_strup(utsname.machine));
1152             r->data.hinfo.os = avahi_strdup(avahi_strup(utsname.sysname));
1153
1154             avahi_log_info("Registering HINFO record with values '%s'/'%s'.", r->data.hinfo.cpu, r->data.hinfo.os);
1155
1156             if (avahi_server_add(s, s->hinfo_entry_group, AVAHI_IF_UNSPEC, AVAHI_PROTO_UNSPEC, AVAHI_PUBLISH_UNIQUE, r) < 0) {
1157                 avahi_log_warn("Failed to add HINFO RR: %s", avahi_strerror(s->error));
1158                 return;
1159             }
1160         }
1161
1162         avahi_record_unref(r);
1163     }
1164
1165     if (avahi_s_entry_group_commit(s->hinfo_entry_group) < 0)
1166         avahi_log_warn("Failed to commit HINFO entry group: %s", avahi_strerror(s->error));
1167
1168 }
1169
1170 static void register_localhost(AvahiServer *s) {
1171     AvahiAddress a;
1172     assert(s);
1173
1174     /* Add localhost entries */
1175     avahi_address_parse("127.0.0.1", AVAHI_PROTO_INET, &a);
1176     avahi_server_add_address(s, NULL, AVAHI_IF_UNSPEC, AVAHI_PROTO_UNSPEC, AVAHI_PUBLISH_NO_PROBE|AVAHI_PUBLISH_NO_ANNOUNCE, "localhost", &a);
1177
1178     avahi_address_parse("::1", AVAHI_PROTO_INET6, &a);
1179     avahi_server_add_address(s, NULL, AVAHI_IF_UNSPEC, AVAHI_PROTO_UNSPEC, AVAHI_PUBLISH_NO_PROBE|AVAHI_PUBLISH_NO_ANNOUNCE, "ip6-localhost", &a);
1180 }
1181
1182 static void register_browse_domain(AvahiServer *s) {
1183     assert(s);
1184
1185     if (!s->config.publish_domain)
1186         return;
1187
1188     if (avahi_domain_equal(s->domain_name, "local"))
1189         return;
1190
1191     if (s->browse_domain_entry_group)
1192         assert(avahi_s_entry_group_is_empty(s->browse_domain_entry_group));
1193     else
1194         s->browse_domain_entry_group = avahi_s_entry_group_new(s, NULL, NULL);
1195
1196     if (!s->browse_domain_entry_group) {
1197         avahi_log_warn("Failed to create browse domain entry group: %s", avahi_strerror(s->error));
1198         return;
1199     }
1200
1201     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) {
1202         avahi_log_warn("Failed to add browse domain RR: %s", avahi_strerror(s->error));
1203         return;
1204     }
1205
1206     if (avahi_s_entry_group_commit(s->browse_domain_entry_group) < 0)
1207         avahi_log_warn("Failed to commit browse domain entry group: %s", avahi_strerror(s->error));
1208 }
1209
1210 static void register_stuff(AvahiServer *s) {
1211     assert(s);
1212
1213     server_set_state(s, AVAHI_SERVER_REGISTERING);
1214     s->n_host_rr_pending ++; /** Make sure that the state isn't changed tp AVAHI_SERVER_RUNNING too early */
1215
1216     register_hinfo(s);
1217     register_browse_domain(s);
1218     avahi_interface_monitor_update_rrs(s->monitor, 0);
1219
1220     s->n_host_rr_pending --;
1221
1222     if (s->n_host_rr_pending == 0)
1223         server_set_state(s, AVAHI_SERVER_RUNNING);
1224 }
1225
1226 static void update_fqdn(AvahiServer *s) {
1227     char *n;
1228
1229     assert(s);
1230     assert(s->host_name);
1231     assert(s->domain_name);
1232
1233     if (!(n = avahi_strdup_printf("%s.%s", s->host_name, s->domain_name)))
1234         return; /* OOM */
1235
1236     avahi_free(s->host_name_fqdn);
1237     s->host_name_fqdn = n;
1238 }
1239
1240 int avahi_server_set_host_name(AvahiServer *s, const char *host_name) {
1241     char *hn = NULL;
1242     assert(s);
1243
1244     AVAHI_CHECK_VALIDITY(s, !host_name || avahi_is_valid_host_name(host_name), AVAHI_ERR_INVALID_HOST_NAME);
1245
1246     if (!host_name) {
1247         hn = avahi_get_host_name_strdup();
1248         hn[strcspn(hn, ".")] = 0;
1249         host_name = hn;
1250     }
1251
1252     if (avahi_domain_equal(s->host_name, host_name) && s->state != AVAHI_SERVER_COLLISION) {
1253         avahi_free(hn);
1254         return avahi_server_set_errno(s, AVAHI_ERR_NO_CHANGE);
1255     }
1256
1257     withdraw_host_rrs(s);
1258
1259     avahi_free(s->host_name);
1260     s->host_name = hn ? hn : avahi_strdup(host_name);
1261
1262     update_fqdn(s);
1263
1264     register_stuff(s);
1265     return AVAHI_OK;
1266 }
1267
1268 int avahi_server_set_domain_name(AvahiServer *s, const char *domain_name) {
1269     char *dn = NULL;
1270     assert(s);
1271
1272     AVAHI_CHECK_VALIDITY(s, !domain_name || avahi_is_valid_domain_name(domain_name), AVAHI_ERR_INVALID_DOMAIN_NAME);
1273
1274     if (!domain_name) {
1275         dn = avahi_strdup("local");
1276         domain_name = dn;
1277     }
1278
1279     if (avahi_domain_equal(s->domain_name, domain_name)) {
1280         avahi_free(dn);
1281         return avahi_server_set_errno(s, AVAHI_ERR_NO_CHANGE);
1282     }
1283
1284     withdraw_host_rrs(s);
1285
1286     avahi_free(s->domain_name);
1287     s->domain_name = avahi_normalize_name_strdup(domain_name);
1288     update_fqdn(s);
1289
1290     register_stuff(s);
1291
1292     avahi_free(dn);
1293     return AVAHI_OK;
1294 }
1295
1296 static int valid_server_config(const AvahiServerConfig *sc) {
1297     AvahiStringList *l;
1298
1299     assert(sc);
1300
1301     if (sc->n_wide_area_servers > AVAHI_WIDE_AREA_SERVERS_MAX)
1302         return AVAHI_ERR_INVALID_CONFIG;
1303
1304     if (sc->host_name && !avahi_is_valid_host_name(sc->host_name))
1305         return AVAHI_ERR_INVALID_HOST_NAME;
1306
1307     if (sc->domain_name && !avahi_is_valid_domain_name(sc->domain_name))
1308         return AVAHI_ERR_INVALID_DOMAIN_NAME;
1309
1310     for (l = sc->browse_domains; l; l = l->next)
1311         if (!avahi_is_valid_domain_name((char*) l->text))
1312             return AVAHI_ERR_INVALID_DOMAIN_NAME;
1313
1314     return AVAHI_OK;
1315 }
1316
1317 static int setup_sockets(AvahiServer *s) {
1318     assert(s);
1319
1320     s->fd_ipv4 = s->config.use_ipv4 ? avahi_open_socket_ipv4(s->config.disallow_other_stacks) : -1;
1321     s->fd_ipv6 = s->config.use_ipv6 ? avahi_open_socket_ipv6(s->config.disallow_other_stacks) : -1;
1322
1323     if (s->fd_ipv6 < 0 && s->fd_ipv4 < 0)
1324         return AVAHI_ERR_NO_NETWORK;
1325
1326     if (s->fd_ipv4 < 0 && s->config.use_ipv4)
1327         avahi_log_notice("Failed to create IPv4 socket, proceeding in IPv6 only mode");
1328     else if (s->fd_ipv6 < 0 && s->config.use_ipv6)
1329         avahi_log_notice("Failed to create IPv6 socket, proceeding in IPv4 only mode");
1330
1331     s->fd_legacy_unicast_ipv4 = s->fd_ipv4 >= 0 && s->config.enable_reflector ? avahi_open_unicast_socket_ipv4() : -1;
1332     s->fd_legacy_unicast_ipv6 = s->fd_ipv6 >= 0 && s->config.enable_reflector ? avahi_open_unicast_socket_ipv6() : -1;
1333
1334     s->watch_ipv4 =
1335         s->watch_ipv6 =
1336         s->watch_legacy_unicast_ipv4 =
1337         s->watch_legacy_unicast_ipv6 = NULL;
1338
1339     if (s->fd_ipv4 >= 0)
1340         s->watch_ipv4 = s->poll_api->watch_new(s->poll_api, s->fd_ipv4, AVAHI_WATCH_IN, mcast_socket_event, s);
1341     if (s->fd_ipv6 >= 0)
1342         s->watch_ipv6 = s->poll_api->watch_new(s->poll_api, s->fd_ipv6, AVAHI_WATCH_IN, mcast_socket_event, s);
1343
1344     if (s->fd_legacy_unicast_ipv4 >= 0)
1345         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);
1346     if (s->fd_legacy_unicast_ipv6 >= 0)
1347         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);
1348
1349     return 0;
1350 }
1351
1352 AvahiServer *avahi_server_new(const AvahiPoll *poll_api, const AvahiServerConfig *sc, AvahiServerCallback callback, void* userdata, int *error) {
1353     AvahiServer *s;
1354     int e;
1355
1356     if (sc && (e = valid_server_config(sc)) < 0) {
1357         if (error)
1358             *error = e;
1359         return NULL;
1360     }
1361
1362     if (!(s = avahi_new(AvahiServer, 1))) {
1363         if (error)
1364             *error = AVAHI_ERR_NO_MEMORY;
1365
1366         return NULL;
1367     }
1368
1369     s->poll_api = poll_api;
1370
1371     if (sc)
1372         avahi_server_config_copy(&s->config, sc);
1373     else
1374         avahi_server_config_init(&s->config);
1375
1376     if ((e = setup_sockets(s)) < 0) {
1377         if (error)
1378             *error = e;
1379
1380         avahi_server_config_free(&s->config);
1381         avahi_free(s);
1382
1383         return NULL;
1384     }
1385
1386     s->n_host_rr_pending = 0;
1387     s->need_entry_cleanup = 0;
1388     s->need_group_cleanup = 0;
1389     s->need_browser_cleanup = 0;
1390     s->hinfo_entry_group = NULL;
1391     s->browse_domain_entry_group = NULL;
1392     s->error = AVAHI_OK;
1393     s->state = AVAHI_SERVER_INVALID;
1394
1395     s->callback = callback;
1396     s->userdata = userdata;
1397
1398     s->time_event_queue = avahi_time_event_queue_new(poll_api);
1399
1400     s->entries_by_key = avahi_hashmap_new((AvahiHashFunc) avahi_key_hash, (AvahiEqualFunc) avahi_key_equal, NULL, NULL);
1401     AVAHI_LLIST_HEAD_INIT(AvahiEntry, s->entries);
1402     AVAHI_LLIST_HEAD_INIT(AvahiGroup, s->groups);
1403
1404     s->record_browser_hashmap = avahi_hashmap_new((AvahiHashFunc) avahi_key_hash, (AvahiEqualFunc) avahi_key_equal, NULL, NULL);
1405     AVAHI_LLIST_HEAD_INIT(AvahiSRecordBrowser, s->record_browsers);
1406     AVAHI_LLIST_HEAD_INIT(AvahiSHostNameResolver, s->host_name_resolvers);
1407     AVAHI_LLIST_HEAD_INIT(AvahiSAddressResolver, s->address_resolvers);
1408     AVAHI_LLIST_HEAD_INIT(AvahiSDomainBrowser, s->domain_browsers);
1409     AVAHI_LLIST_HEAD_INIT(AvahiSServiceTypeBrowser, s->service_type_browsers);
1410     AVAHI_LLIST_HEAD_INIT(AvahiSServiceBrowser, s->service_browsers);
1411     AVAHI_LLIST_HEAD_INIT(AvahiSServiceResolver, s->service_resolvers);
1412     AVAHI_LLIST_HEAD_INIT(AvahiSDNSServerBrowser, s->dns_server_browsers);
1413
1414     s->legacy_unicast_reflect_slots = NULL;
1415     s->legacy_unicast_reflect_id = 0;
1416
1417     s->record_list = avahi_record_list_new();
1418
1419     /* Get host name */
1420     s->host_name = s->config.host_name ? avahi_normalize_name_strdup(s->config.host_name) : avahi_get_host_name_strdup();
1421     s->host_name[strcspn(s->host_name, ".")] = 0;
1422     s->domain_name = s->config.domain_name ? avahi_normalize_name_strdup(s->config.domain_name) : avahi_strdup("local");
1423     s->host_name_fqdn = NULL;
1424     update_fqdn(s);
1425
1426     do {
1427         s->local_service_cookie = (uint32_t) rand() * (uint32_t) rand();
1428     } while (s->local_service_cookie == AVAHI_SERVICE_COOKIE_INVALID);
1429
1430     if (s->config.enable_wide_area) {
1431         s->wide_area_lookup_engine = avahi_wide_area_engine_new(s);
1432         avahi_wide_area_set_servers(s->wide_area_lookup_engine, s->config.wide_area_servers, s->config.n_wide_area_servers);
1433     } else
1434         s->wide_area_lookup_engine = NULL;
1435
1436     s->multicast_lookup_engine = avahi_multicast_lookup_engine_new(s);
1437
1438     s->monitor = avahi_interface_monitor_new(s);
1439     avahi_interface_monitor_sync(s->monitor);
1440
1441     register_localhost(s);
1442     register_stuff(s);
1443
1444     return s;
1445 }
1446
1447 void avahi_server_free(AvahiServer* s) {
1448     assert(s);
1449
1450     /* Remove all browsers */
1451
1452     while (s->dns_server_browsers)
1453         avahi_s_dns_server_browser_free(s->dns_server_browsers);
1454     while (s->host_name_resolvers)
1455         avahi_s_host_name_resolver_free(s->host_name_resolvers);
1456     while (s->address_resolvers)
1457         avahi_s_address_resolver_free(s->address_resolvers);
1458     while (s->domain_browsers)
1459         avahi_s_domain_browser_free(s->domain_browsers);
1460     while (s->service_type_browsers)
1461         avahi_s_service_type_browser_free(s->service_type_browsers);
1462     while (s->service_browsers)
1463         avahi_s_service_browser_free(s->service_browsers);
1464     while (s->service_resolvers)
1465         avahi_s_service_resolver_free(s->service_resolvers);
1466     while (s->record_browsers)
1467         avahi_s_record_browser_destroy(s->record_browsers);
1468
1469     /* Remove all locally rgeistered stuff */
1470
1471     while(s->entries)
1472         avahi_entry_free(s, s->entries);
1473
1474     avahi_interface_monitor_free(s->monitor);
1475
1476     while (s->groups)
1477         avahi_entry_group_free(s, s->groups);
1478
1479     free_slots(s);
1480
1481     avahi_hashmap_free(s->entries_by_key);
1482     avahi_record_list_free(s->record_list);
1483     avahi_hashmap_free(s->record_browser_hashmap);
1484
1485     if (s->wide_area_lookup_engine)
1486         avahi_wide_area_engine_free(s->wide_area_lookup_engine);
1487     avahi_multicast_lookup_engine_free(s->multicast_lookup_engine);
1488
1489     avahi_time_event_queue_free(s->time_event_queue);
1490
1491     /* Free watches */
1492
1493     if (s->watch_ipv4)
1494         s->poll_api->watch_free(s->watch_ipv4);
1495     if (s->watch_ipv6)
1496         s->poll_api->watch_free(s->watch_ipv6);
1497
1498     if (s->watch_legacy_unicast_ipv4)
1499         s->poll_api->watch_free(s->watch_legacy_unicast_ipv4);
1500     if (s->watch_legacy_unicast_ipv6)
1501         s->poll_api->watch_free(s->watch_legacy_unicast_ipv6);
1502
1503     /* Free sockets */
1504
1505     if (s->fd_ipv4 >= 0)
1506         close(s->fd_ipv4);
1507     if (s->fd_ipv6 >= 0)
1508         close(s->fd_ipv6);
1509
1510     if (s->fd_legacy_unicast_ipv4 >= 0)
1511         close(s->fd_legacy_unicast_ipv4);
1512     if (s->fd_legacy_unicast_ipv6 >= 0)
1513         close(s->fd_legacy_unicast_ipv6);
1514
1515     /* Free other stuff */
1516
1517     avahi_free(s->host_name);
1518     avahi_free(s->domain_name);
1519     avahi_free(s->host_name_fqdn);
1520
1521     avahi_server_config_free(&s->config);
1522
1523     avahi_free(s);
1524 }
1525
1526 const char* avahi_server_get_domain_name(AvahiServer *s) {
1527     assert(s);
1528
1529     return s->domain_name;
1530 }
1531
1532 const char* avahi_server_get_host_name(AvahiServer *s) {
1533     assert(s);
1534
1535     return s->host_name;
1536 }
1537
1538 const char* avahi_server_get_host_name_fqdn(AvahiServer *s) {
1539     assert(s);
1540
1541     return s->host_name_fqdn;
1542 }
1543
1544 void* avahi_server_get_data(AvahiServer *s) {
1545     assert(s);
1546
1547     return s->userdata;
1548 }
1549
1550 void avahi_server_set_data(AvahiServer *s, void* userdata) {
1551     assert(s);
1552
1553     s->userdata = userdata;
1554 }
1555
1556 AvahiServerState avahi_server_get_state(AvahiServer *s) {
1557     assert(s);
1558
1559     return s->state;
1560 }
1561
1562 AvahiServerConfig* avahi_server_config_init(AvahiServerConfig *c) {
1563     assert(c);
1564
1565     memset(c, 0, sizeof(AvahiServerConfig));
1566     c->use_ipv6 = 1;
1567     c->use_ipv4 = 1;
1568     c->allow_interfaces = NULL;
1569     c->deny_interfaces = NULL;
1570     c->host_name = NULL;
1571     c->domain_name = NULL;
1572     c->check_response_ttl = 0;
1573     c->publish_hinfo = 1;
1574     c->publish_addresses = 1;
1575     c->publish_workstation = 1;
1576     c->publish_domain = 1;
1577     c->use_iff_running = 0;
1578     c->enable_reflector = 0;
1579     c->reflect_ipv = 0;
1580     c->add_service_cookie = 0;
1581     c->enable_wide_area = 0;
1582     c->n_wide_area_servers = 0;
1583     c->disallow_other_stacks = 0;
1584     c->browse_domains = NULL;
1585     c->disable_publishing = 0;
1586     c->allow_point_to_point = 0;
1587     c->publish_aaaa_on_ipv4 = 1;
1588     c->publish_a_on_ipv6 = 0;
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 }