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("Recieved conflicting probe [%s]. Local host won.", t);
 232         else if (lost) {
 233             avahi_log_debug("Recieved 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("Recieved 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("Recieved 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("Recieved 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("Recieved 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 /* 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
 442                         break;
 443                     }
 444
 445                     if (avahi_dns_packet_get_field(reply, AVAHI_DNS_FIELD_ANCOUNT) == 0) {
 446                         size_t size;
 447
 448                         /* The record is too large for one packet, so create a larger packet */
 449
 450                         avahi_dns_packet_free(reply);
 451                         size = avahi_record_get_estimate_size(r) + AVAHI_DNS_PACKET_HEADER_SIZE;
 452                         if (size > AVAHI_DNS_PACKET_SIZE_MAX)
 453                             size = AVAHI_DNS_PACKET_SIZE_MAX;
 454
 455                         if (!(reply = avahi_dns_packet_new_reply(p, size, 0, 1)))
 456                             break; /* OOM */
 457
 458                         if (!avahi_dns_packet_append_record(reply, r, flush_cache, 0)) {
 459                             char *t;
 460                             avahi_dns_packet_free(reply);
 461                             t = avahi_record_to_string(r);
 462                             avahi_log_warn("Record [%s] too large, doesn't fit in any packet!", t);
 463                             avahi_free(t);
 464                             break;
 465                         } else
 466                             avahi_dns_packet_inc_field(reply, AVAHI_DNS_FIELD_ANCOUNT);
 467                     }
 468
 469                     /* Appending the record didn't succeeed, so let's send this packet, and create a new one */
 470                     avahi_interface_send_packet_unicast(i, reply, a, port);
 471                     avahi_dns_packet_free(reply);
 472                     reply = NULL;
 473                 }
 474             }
 475
 476             avahi_record_unref(r);
 477         }
 478
 479         if (reply) {
 480             if (avahi_dns_packet_get_field(reply, AVAHI_DNS_FIELD_ANCOUNT) != 0)
 481                 avahi_interface_send_packet_unicast(i, reply, a, port);
 482             avahi_dns_packet_free(reply);
 483         }
 484     }
 485
 486     avahi_record_list_flush(s->record_list);
 487 }
 488
 489 static void reflect_response(AvahiServer *s, AvahiInterface *i, AvahiRecord *r, int flush_cache) {
 490     AvahiInterface *j;
 491
 492     assert(s);
 493     assert(i);
 494     assert(r);
 495
 496     if (!s->config.enable_reflector)
 497         return;
 498
 499     for (j = s->monitor->interfaces; j; j = j->interface_next)
 500         if (j != i && (s->config.reflect_ipv || j->protocol == i->protocol))
 501             avahi_interface_post_response(j, r, flush_cache, NULL, 1);
 502 }
 503
 504 static void* reflect_cache_walk_callback(AvahiCache *c, AvahiKey *pattern, AvahiCacheEntry *e, void* userdata) {
 505     AvahiServer *s = userdata;
 506
 507     assert(c);
 508     assert(pattern);
 509     assert(e);
 510     assert(s);
 511
 512     avahi_record_list_push(s->record_list, e->record, e->cache_flush, 0, 0);
 513     return NULL;
 514 }
 515
 516 static void reflect_query(AvahiServer *s, AvahiInterface *i, AvahiKey *k) {
 517     AvahiInterface *j;
 518
 519     assert(s);
 520     assert(i);
 521     assert(k);
 522
 523     if (!s->config.enable_reflector)
 524         return;
 525
 526     for (j = s->monitor->interfaces; j; j = j->interface_next)
 527         if (j != i && (s->config.reflect_ipv || j->protocol == i->protocol)) {
 528             /* Post the query to other networks */
 529             avahi_interface_post_query(j, k, 1, NULL);
 530
 531             /* Reply from caches of other network. This is needed to
 532              * "work around" known answer suppression. */
 533
 534             avahi_cache_walk(j->cache, k, reflect_cache_walk_callback, s);
 535         }
 536 }
 537
 538 static void reflect_probe(AvahiServer *s, AvahiInterface *i, AvahiRecord *r) {
 539     AvahiInterface *j;
 540
 541     assert(s);
 542     assert(i);
 543     assert(r);
 544
 545     if (!s->config.enable_reflector)
 546         return;
 547
 548     for (j = s->monitor->interfaces; j; j = j->interface_next)
 549         if (j != i && (s->config.reflect_ipv || j->protocol == i->protocol))
 550             avahi_interface_post_probe(j, r, 1);
 551 }
 552
 553 static void handle_query_packet(AvahiServer *s, AvahiDnsPacket *p, AvahiInterface *i, const AvahiAddress *a, uint16_t port, int legacy_unicast, int from_local_iface) {
 554     size_t n;
 555     int is_probe;
 556
 557     assert(s);
 558     assert(p);
 559     assert(i);
 560     assert(a);
 561
 562     assert(avahi_record_list_is_empty(s->record_list));
 563
 564     is_probe = avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_NSCOUNT) > 0;
 565
 566     /* Handle the questions */
 567     for (n = avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_QDCOUNT); n > 0; n --) {
 568         AvahiKey *key;
 569         int unicast_response = 0;
 570
 571         if (!(key = avahi_dns_packet_consume_key(p, &unicast_response))) {
 572             avahi_log_warn("Packet too short (1)");
 573             goto fail;
 574         }
 575
 576         if (!legacy_unicast && !from_local_iface) {
 577             reflect_query(s, i, key);
 578             avahi_cache_start_poof(i->cache, key, a);
 579         }
 580
 581         if (avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_ANCOUNT) == 0 &&
 582             !(avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_FLAGS) & AVAHI_DNS_FLAG_TC))
 583             /* Allow our own queries to be suppressed by incoming
 584              * queries only when they do not include known answers */
 585             avahi_query_scheduler_incoming(i->query_scheduler, key);
 586
 587         avahi_server_prepare_matching_responses(s, i, key, unicast_response);
 588         avahi_key_unref(key);
 589     }
 590
 591     if (!legacy_unicast) {
 592
 593         /* Known Answer Suppression */
 594         for (n = avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_ANCOUNT); n > 0; n --) {
 595             AvahiRecord *record;
 596             int unique = 0;
 597
 598             if (!(record = avahi_dns_packet_consume_record(p, &unique))) {
 599                 avahi_log_warn("Packet too short (2)");
 600                 goto fail;
 601             }
 602
 603             if (handle_conflict(s, i, record, unique)) {
 604                 avahi_response_scheduler_suppress(i->response_scheduler, record, a);
 605                 avahi_record_list_drop(s->record_list, record);
 606                 avahi_cache_stop_poof(i->cache, record, a);
 607             }
 608
 609             avahi_record_unref(record);
 610         }
 611
 612         /* Probe record */
 613         for (n = avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_NSCOUNT); n > 0; n --) {
 614             AvahiRecord *record;
 615             int unique = 0;
 616
 617             if (!(record = avahi_dns_packet_consume_record(p, &unique))) {
 618                 avahi_log_warn("Packet too short (3)");
 619                 goto fail;
 620             }
 621
 622             if (!avahi_key_is_pattern(record->key)) {
 623                 if (!from_local_iface)
 624                     reflect_probe(s, i, record);
 625                 incoming_probe(s, record, i);
 626             }
 627
 628             avahi_record_unref(record);
 629         }
 630     }
 631
 632     if (!avahi_record_list_is_empty(s->record_list))
 633         avahi_server_generate_response(s, i, p, a, port, legacy_unicast, is_probe);
 634
 635     return;
 636
 637 fail:
 638     avahi_record_list_flush(s->record_list);
 639 }
 640
 641 static void handle_response_packet(AvahiServer *s, AvahiDnsPacket *p, AvahiInterface *i, const AvahiAddress *a, int from_local_iface) {
 642     unsigned n;
 643
 644     assert(s);
 645     assert(p);
 646     assert(i);
 647     assert(a);
 648
 649     for (n = avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_ANCOUNT) +
 650              avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_ARCOUNT); n > 0; n--) {
 651         AvahiRecord *record;
 652         int cache_flush = 0;
 653 /*         char *txt; */
 654
 655         if (!(record = avahi_dns_packet_consume_record(p, &cache_flush))) {
 656             avahi_log_warn("Packet too short (4)");
 657             break;
 658         }
 659
 660         if (!avahi_key_is_pattern(record->key)) {
 661
 662             if (handle_conflict(s, i, record, cache_flush)) {
 663                 if (!from_local_iface)
 664                     reflect_response(s, i, record, cache_flush);
 665                 avahi_cache_update(i->cache, record, cache_flush, a);
 666                 avahi_response_scheduler_incoming(i->response_scheduler, record, cache_flush);
 667             }
 668         }
 669
 670         avahi_record_unref(record);
 671     }
 672
 673     /* If the incoming response contained a conflicting record, some
 674        records have been scheduling for sending. We need to flush them
 675        here. */
 676     if (!avahi_record_list_is_empty(s->record_list))
 677         avahi_server_generate_response(s, i, NULL, NULL, 0, 0, 1);
 678 }
 679
 680 static AvahiLegacyUnicastReflectSlot* allocate_slot(AvahiServer *s) {
 681     unsigned n, idx = (unsigned) -1;
 682     AvahiLegacyUnicastReflectSlot *slot;
 683
 684     assert(s);
 685
 686     if (!s->legacy_unicast_reflect_slots)
 687         s->legacy_unicast_reflect_slots = avahi_new0(AvahiLegacyUnicastReflectSlot*, AVAHI_LEGACY_UNICAST_REFLECT_SLOTS_MAX);
 688
 689     for (n = 0; n < AVAHI_LEGACY_UNICAST_REFLECT_SLOTS_MAX; n++, s->legacy_unicast_reflect_id++) {
 690         idx = s->legacy_unicast_reflect_id % AVAHI_LEGACY_UNICAST_REFLECT_SLOTS_MAX;
 691
 692         if (!s->legacy_unicast_reflect_slots[idx])
 693             break;
 694     }
 695
 696     if (idx == (unsigned) -1 || s->legacy_unicast_reflect_slots[idx])
 697         return NULL;
 698
 699     if (!(slot = avahi_new(AvahiLegacyUnicastReflectSlot, 1)))
 700         return NULL; /* OOM */
 701
 702     s->legacy_unicast_reflect_slots[idx] = slot;
 703     slot->id = s->legacy_unicast_reflect_id++;
 704     slot->server = s;
 705
 706     return slot;
 707 }
 708
 709 static void deallocate_slot(AvahiServer *s, AvahiLegacyUnicastReflectSlot *slot) {
 710     unsigned idx;
 711
 712     assert(s);
 713     assert(slot);
 714
 715     idx = slot->id % AVAHI_LEGACY_UNICAST_REFLECT_SLOTS_MAX;
 716
 717     assert(s->legacy_unicast_reflect_slots[idx] == slot);
 718
 719     avahi_time_event_free(slot->time_event);
 720
 721     avahi_free(slot);
 722     s->legacy_unicast_reflect_slots[idx] = NULL;
 723 }
 724
 725 static void free_slots(AvahiServer *s) {
 726     unsigned idx;
 727     assert(s);
 728
 729     if (!s->legacy_unicast_reflect_slots)
 730         return;
 731
 732     for (idx = 0; idx < AVAHI_LEGACY_UNICAST_REFLECT_SLOTS_MAX; idx ++)
 733         if (s->legacy_unicast_reflect_slots[idx])
 734             deallocate_slot(s, s->legacy_unicast_reflect_slots[idx]);
 735
 736     avahi_free(s->legacy_unicast_reflect_slots);
 737     s->legacy_unicast_reflect_slots = NULL;
 738 }
 739
 740 static AvahiLegacyUnicastReflectSlot* find_slot(AvahiServer *s, uint16_t id) {
 741     unsigned idx;
 742
 743     assert(s);
 744
 745     if (!s->legacy_unicast_reflect_slots)
 746         return NULL;
 747
 748     idx = id % AVAHI_LEGACY_UNICAST_REFLECT_SLOTS_MAX;
 749
 750     if (!s->legacy_unicast_reflect_slots[idx] || s->legacy_unicast_reflect_slots[idx]->id != id)
 751         return NULL;
 752
 753     return s->legacy_unicast_reflect_slots[idx];
 754 }
 755
 756 static void legacy_unicast_reflect_slot_timeout(AvahiTimeEvent *e, void *userdata) {
 757     AvahiLegacyUnicastReflectSlot *slot = userdata;
 758
 759     assert(e);
 760     assert(slot);
 761     assert(slot->time_event == e);
 762
 763     deallocate_slot(slot->server, slot);
 764 }
 765
 766 static void reflect_legacy_unicast_query_packet(AvahiServer *s, AvahiDnsPacket *p, AvahiInterface *i, const AvahiAddress *a, uint16_t port) {
 767     AvahiLegacyUnicastReflectSlot *slot;
 768     AvahiInterface *j;
 769
 770     assert(s);
 771     assert(p);
 772     assert(i);
 773     assert(a);
 774     assert(port > 0);
 775     assert(i->protocol == a->proto);
 776
 777     if (!s->config.enable_reflector)
 778         return;
 779
 780     /* Reflecting legacy unicast queries is a little more complicated
 781        than reflecting normal queries, since we must route the
 782        responses back to the right client. Therefore we must store
 783        some information for finding the right client contact data for
 784        response packets. In contrast to normal queries legacy
 785        unicast query and response packets are reflected untouched and
 786        are not reassembled into larger packets */
 787
 788     if (!(slot = allocate_slot(s))) {
 789         /* No slot available, we drop this legacy unicast query */
 790         avahi_log_warn("No slot available for legacy unicast reflection, dropping query packet.");
 791         return;
 792     }
 793
 794     slot->original_id = avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_ID);
 795     slot->address = *a;
 796     slot->port = port;
 797     slot->interface = i->hardware->index;
 798
 799     avahi_elapse_time(&slot->elapse_time, 2000, 0);
 800     slot->time_event = avahi_time_event_new(s->time_event_queue, &slot->elapse_time, legacy_unicast_reflect_slot_timeout, slot);
 801
 802     /* Patch the packet with our new locally generatet id */
 803     avahi_dns_packet_set_field(p, AVAHI_DNS_FIELD_ID, slot->id);
 804
 805     for (j = s->monitor->interfaces; j; j = j->interface_next)
 806         if (avahi_interface_is_relevant(j) &&
 807             j != i &&
 808             (s->config.reflect_ipv || j->protocol == i->protocol)) {
 809
 810             if (j->protocol == AVAHI_PROTO_INET && s->fd_legacy_unicast_ipv4 >= 0) {
 811                 avahi_send_dns_packet_ipv4(s->fd_legacy_unicast_ipv4, j->hardware->index, p, NULL, NULL, 0);
 812             } else if (j->protocol == AVAHI_PROTO_INET6 && s->fd_legacy_unicast_ipv6 >= 0)
 813                 avahi_send_dns_packet_ipv6(s->fd_legacy_unicast_ipv6, j->hardware->index, p, NULL, NULL, 0);
 814         }
 815
 816     /* Reset the id */
 817     avahi_dns_packet_set_field(p, AVAHI_DNS_FIELD_ID, slot->original_id);
 818 }
 819
 820 static int originates_from_local_legacy_unicast_socket(AvahiServer *s, const AvahiAddress *address, uint16_t port) {
 821     assert(s);
 822     assert(address);
 823     assert(port > 0);
 824
 825     if (!s->config.enable_reflector)
 826         return 0;
 827
 828     if (!avahi_address_is_local(s->monitor, address))
 829         return 0;
 830
 831     if (address->proto == AVAHI_PROTO_INET && s->fd_legacy_unicast_ipv4 >= 0) {
 832         struct sockaddr_in lsa;
 833         socklen_t l = sizeof(lsa);
 834
 835         if (getsockname(s->fd_legacy_unicast_ipv4, (struct sockaddr*) &lsa, &l) != 0)
 836             avahi_log_warn("getsockname(): %s", strerror(errno));
 837         else
 838             return lsa.sin_port == port;
 839
 840     }
 841
 842     if (address->proto == AVAHI_PROTO_INET6 && s->fd_legacy_unicast_ipv6 >= 0) {
 843         struct sockaddr_in6 lsa;
 844         socklen_t l = sizeof(lsa);
 845
 846         if (getsockname(s->fd_legacy_unicast_ipv6, (struct sockaddr*) &lsa, &l) != 0)
 847             avahi_log_warn("getsockname(): %s", strerror(errno));
 848         else
 849             return lsa.sin6_port == port;
 850     }
 851
 852     return 0;
 853 }
 854
 855 static int is_mdns_mcast_address(const AvahiAddress *a) {
 856     AvahiAddress b;
 857     assert(a);
 858
 859     avahi_address_parse(a->proto == AVAHI_PROTO_INET ? AVAHI_IPV4_MCAST_GROUP : AVAHI_IPV6_MCAST_GROUP, a->proto, &b);
 860     return avahi_address_cmp(a, &b) == 0;
 861 }
 862
 863 static int originates_from_local_iface(AvahiServer *s, AvahiIfIndex iface, const AvahiAddress *a, uint16_t port) {
 864     assert(s);
 865     assert(iface != AVAHI_IF_UNSPEC);
 866     assert(a);
 867
 868     /* If it isn't the MDNS port it can't be generated by us */
 869     if (port != AVAHI_MDNS_PORT)
 870         return 0;
 871
 872     return avahi_interface_has_address(s->monitor, iface, a);
 873 }
 874
 875 static void dispatch_packet(AvahiServer *s, AvahiDnsPacket *p, const AvahiAddress *src_address, uint16_t port, const AvahiAddress *dst_address, AvahiIfIndex iface, int ttl) {
 876     AvahiInterface *i;
 877     int from_local_iface = 0;
 878
 879     assert(s);
 880     assert(p);
 881     assert(src_address);
 882     assert(dst_address);
 883     assert(iface > 0);
 884     assert(src_address->proto == dst_address->proto);
 885
 886     if (!(i = avahi_interface_monitor_get_interface(s->monitor, iface, src_address->proto)) ||
 887         !avahi_interface_is_relevant(i)) {
 888         avahi_log_warn("Recieved packet from invalid interface.");
 889         return;
 890     }
 891
 892     if (avahi_address_is_ipv4_in_ipv6(src_address))
 893         /* This is an IPv4 address encapsulated in IPv6, so let's ignore it. */
 894         return;
 895
 896     if (originates_from_local_legacy_unicast_socket(s, src_address, port))
 897         /* This originates from our local reflector, so let's ignore it */
 898         return;
 899
 900     /* We don't want to reflect local traffic, so we check if this packet is generated locally. */
 901     if (s->config.enable_reflector)
 902         from_local_iface = originates_from_local_iface(s, iface, src_address, port);
 903
 904     if (avahi_dns_packet_check_valid_multicast(p) < 0) {
 905         avahi_log_warn("Recieved invalid packet.");
 906         return;
 907     }
 908
 909     if (avahi_dns_packet_is_query(p)) {
 910         int legacy_unicast = 0;
 911
 912         if (avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_ARCOUNT) != 0) {
 913             avahi_log_warn("Invalid query packet.");
 914             return;
 915         }
 916
 917         if (port != AVAHI_MDNS_PORT) {
 918             /* Legacy Unicast */
 919
 920             if ((avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_ANCOUNT) != 0 ||
 921                  avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_NSCOUNT) != 0)) {
 922                 avahi_log_warn("Invalid legacy unicast query packet.");
 923                 return;
 924             }
 925
 926             legacy_unicast = 1;
 927         }
 928
 929         if (legacy_unicast)
 930             reflect_legacy_unicast_query_packet(s, p, i, src_address, port);
 931
 932         handle_query_packet(s, p, i, src_address, port, legacy_unicast, from_local_iface);
 933
 934     } else {
 935         if (port != AVAHI_MDNS_PORT) {
 936             avahi_log_warn("Recieved repsonse with invalid source port %u on interface '%s.%i'", port, i->hardware->name, i->protocol);
 937             return;
 938         }
 939
 940         if (ttl != 255 && s->config.check_response_ttl) {
 941             avahi_log_warn("Recieved response with invalid TTL %u on interface '%s.%i'.", ttl, i->hardware->name, i->protocol);
 942             return;
 943         }
 944
 945         if (!is_mdns_mcast_address(dst_address) &&
 946             !avahi_interface_address_on_link(i, src_address)) {
 947             avahi_log_warn("Received non-local response on interface '%s.%i'.", i->hardware->name, i->protocol);
 948             return;
 949         }
 950
 951         if (avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_QDCOUNT) != 0 ||
 952             avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_ANCOUNT) == 0 ||
 953             avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_NSCOUNT) != 0) {
 954             avahi_log_warn("Invalid response packet.");
 955             return;
 956         }
 957
 958         handle_response_packet(s, p, i, src_address, from_local_iface);
 959     }
 960 }
 961
 962 static void dispatch_legacy_unicast_packet(AvahiServer *s, AvahiDnsPacket *p) {
 963     AvahiInterface *j;
 964     AvahiLegacyUnicastReflectSlot *slot;
 965
 966     assert(s);
 967     assert(p);
 968
 969     if (avahi_dns_packet_check_valid(p) < 0 || avahi_dns_packet_is_query(p)) {
 970         avahi_log_warn("Recieved invalid packet.");
 971         return;
 972     }
 973
 974     if (!(slot = find_slot(s, avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_ID)))) {
 975         avahi_log_warn("Recieved legacy unicast response with unknown id");
 976         return;
 977     }
 978
 979     if (!(j = avahi_interface_monitor_get_interface(s->monitor, slot->interface, slot->address.proto)) ||
 980         !avahi_interface_is_relevant(j))
 981         return;
 982
 983     /* Patch the original ID into this response */
 984     avahi_dns_packet_set_field(p, AVAHI_DNS_FIELD_ID, slot->original_id);
 985
 986     /* Forward the response to the correct client */
 987     avahi_interface_send_packet_unicast(j, p, &slot->address, slot->port);
 988
 989     /* Undo changes to packet */
 990     avahi_dns_packet_set_field(p, AVAHI_DNS_FIELD_ID, slot->id);
 991 }
 992
 993 static void cleanup_dead(AvahiServer *s) {
 994     assert(s);
 995
 996     avahi_cleanup_dead_entries(s);
 997     avahi_browser_cleanup(s);
 998 }
 999
1000 static void mcast_socket_event(AvahiWatch *w, int fd, AvahiWatchEvent events, void *userdata) {
1001     AvahiServer *s = userdata;
1002     AvahiAddress dest, src;
1003     AvahiDnsPacket *p = NULL;
1004     AvahiIfIndex iface;
1005     uint16_t port;
1006     uint8_t ttl;
1007
1008     assert(w);
1009     assert(fd >= 0);
1010     assert(events & AVAHI_WATCH_IN);
1011
1012     if (fd == s->fd_ipv4) {
1013         dest.proto = src.proto = AVAHI_PROTO_INET;
1014         p = avahi_recv_dns_packet_ipv4(s->fd_ipv4, &src.data.ipv4, &port, &dest.data.ipv4, &iface, &ttl);
1015     } else {
1016         assert(fd == s->fd_ipv6);
1017         dest.proto = src.proto = AVAHI_PROTO_INET6;
1018         p = avahi_recv_dns_packet_ipv6(s->fd_ipv6, &src.data.ipv6, &port, &dest.data.ipv6, &iface, &ttl);
1019     }
1020
1021     if (p) {
1022         if (iface == AVAHI_IF_UNSPEC)
1023             iface = avahi_find_interface_for_address(s->monitor, &dest);
1024
1025         if (iface != AVAHI_IF_UNSPEC)
1026             dispatch_packet(s, p, &src, port, &dest, iface, ttl);
1027         else
1028             avahi_log_error("Incoming packet recieved on address that isn't local.");
1029
1030         avahi_dns_packet_free(p);
1031
1032         cleanup_dead(s);
1033     }
1034 }
1035
1036 static void legacy_unicast_socket_event(AvahiWatch *w, int fd, AvahiWatchEvent events, void *userdata) {
1037     AvahiServer *s = userdata;
1038     AvahiDnsPacket *p = NULL;
1039
1040     assert(w);
1041     assert(fd >= 0);
1042     assert(events & AVAHI_WATCH_IN);
1043
1044     if (fd == s->fd_legacy_unicast_ipv4)
1045         p = avahi_recv_dns_packet_ipv4(s->fd_legacy_unicast_ipv4, NULL, NULL, NULL, NULL, NULL);
1046     else {
1047         assert(fd == s->fd_legacy_unicast_ipv6);
1048         p = avahi_recv_dns_packet_ipv6(s->fd_legacy_unicast_ipv6, NULL, NULL, NULL, NULL, NULL);
1049     }
1050
1051     if (p) {
1052         dispatch_legacy_unicast_packet(s, p);
1053         avahi_dns_packet_free(p);
1054
1055         cleanup_dead(s);
1056     }
1057 }
1058
1059 static void server_set_state(AvahiServer *s, AvahiServerState state) {
1060     assert(s);
1061
1062     if (s->state == state)
1063         return;
1064
1065     s->state = state;
1066
1067     avahi_interface_monitor_update_rrs(s->monitor, 0);
1068
1069     if (s->callback)
1070         s->callback(s, state, s->userdata);
1071 }
1072
1073 static void withdraw_host_rrs(AvahiServer *s) {
1074     assert(s);
1075
1076     if (s->hinfo_entry_group)
1077         avahi_s_entry_group_reset(s->hinfo_entry_group);
1078
1079     if (s->browse_domain_entry_group)
1080         avahi_s_entry_group_reset(s->browse_domain_entry_group);
1081
1082     avahi_interface_monitor_update_rrs(s->monitor, 1);
1083     s->n_host_rr_pending = 0;
1084 }
1085
1086 void avahi_server_decrease_host_rr_pending(AvahiServer *s) {
1087     assert(s);
1088
1089     assert(s->n_host_rr_pending > 0);
1090
1091     if (--s->n_host_rr_pending == 0)
1092         server_set_state(s, AVAHI_SERVER_RUNNING);
1093 }
1094
1095 void avahi_host_rr_entry_group_callback(AvahiServer *s, AvahiSEntryGroup *g, AvahiEntryGroupState state, AVAHI_GCC_UNUSED void *userdata) {
1096     assert(s);
1097     assert(g);
1098
1099     if (state == AVAHI_ENTRY_GROUP_REGISTERING &&
1100         s->state == AVAHI_SERVER_REGISTERING)
1101         s->n_host_rr_pending ++;
1102
1103     else if (state == AVAHI_ENTRY_GROUP_COLLISION &&
1104         (s->state == AVAHI_SERVER_REGISTERING || s->state == AVAHI_SERVER_RUNNING)) {
1105         withdraw_host_rrs(s);
1106         server_set_state(s, AVAHI_SERVER_COLLISION);
1107
1108     } else if (state == AVAHI_ENTRY_GROUP_ESTABLISHED &&
1109                s->state == AVAHI_SERVER_REGISTERING)
1110         avahi_server_decrease_host_rr_pending(s);
1111 }
1112
1113 static void register_hinfo(AvahiServer *s) {
1114     struct utsname utsname;
1115     AvahiRecord *r;
1116
1117     assert(s);
1118
1119     if (!s->config.publish_hinfo)
1120         return;
1121
1122     if (s->hinfo_entry_group)
1123         assert(avahi_s_entry_group_is_empty(s->hinfo_entry_group));
1124     else
1125         s->hinfo_entry_group = avahi_s_entry_group_new(s, avahi_host_rr_entry_group_callback, NULL);
1126
1127     if (!s->hinfo_entry_group) {
1128         avahi_log_warn("Failed to create HINFO entry group: %s", avahi_strerror(s->error));
1129         return;
1130     }
1131
1132     /* Fill in HINFO rr */
1133     if ((r = avahi_record_new_full(s->host_name_fqdn, AVAHI_DNS_CLASS_IN, AVAHI_DNS_TYPE_HINFO, AVAHI_DEFAULT_TTL_HOST_NAME))) {
1134
1135         if (uname(&utsname) < 0)
1136             avahi_log_warn("uname() failed: %s\n", avahi_strerror(errno));
1137         else {
1138
1139             r->data.hinfo.cpu = avahi_strdup(avahi_strup(utsname.machine));
1140             r->data.hinfo.os = avahi_strdup(avahi_strup(utsname.sysname));
1141
1142             avahi_log_info("Registering HINFO record with values '%s'/'%s'.", r->data.hinfo.cpu, r->data.hinfo.os);
1143
1144             if (avahi_server_add(s, s->hinfo_entry_group, AVAHI_IF_UNSPEC, AVAHI_PROTO_UNSPEC, AVAHI_PUBLISH_UNIQUE, r) < 0) {
1145                 avahi_log_warn("Failed to add HINFO RR: %s", avahi_strerror(s->error));
1146                 return;
1147             }
1148         }
1149
1150         avahi_record_unref(r);
1151     }
1152
1153     if (avahi_s_entry_group_commit(s->hinfo_entry_group) < 0)
1154         avahi_log_warn("Failed to commit HINFO entry group: %s", avahi_strerror(s->error));
1155
1156 }
1157
1158 static void register_localhost(AvahiServer *s) {
1159     AvahiAddress a;
1160     assert(s);
1161
1162     /* Add localhost entries */
1163     avahi_address_parse("127.0.0.1", AVAHI_PROTO_INET, &a);
1164     avahi_server_add_address(s, NULL, AVAHI_IF_UNSPEC, AVAHI_PROTO_UNSPEC, AVAHI_PUBLISH_NO_PROBE|AVAHI_PUBLISH_NO_ANNOUNCE, "localhost", &a);
1165
1166     avahi_address_parse("::1", AVAHI_PROTO_INET6, &a);
1167     avahi_server_add_address(s, NULL, AVAHI_IF_UNSPEC, AVAHI_PROTO_UNSPEC, AVAHI_PUBLISH_NO_PROBE|AVAHI_PUBLISH_NO_ANNOUNCE, "ip6-localhost", &a);
1168 }
1169
1170 static void register_browse_domain(AvahiServer *s) {
1171     assert(s);
1172
1173     if (!s->config.publish_domain)
1174         return;
1175
1176     if (avahi_domain_equal(s->domain_name, "local"))
1177         return;
1178
1179     if (s->browse_domain_entry_group)
1180         assert(avahi_s_entry_group_is_empty(s->browse_domain_entry_group));
1181     else
1182         s->browse_domain_entry_group = avahi_s_entry_group_new(s, NULL, NULL);
1183
1184     if (!s->browse_domain_entry_group) {
1185         avahi_log_warn("Failed to create browse domain entry group: %s", avahi_strerror(s->error));
1186         return;
1187     }
1188
1189     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) {
1190         avahi_log_warn("Failed to add browse domain RR: %s", avahi_strerror(s->error));
1191         return;
1192     }
1193
1194     if (avahi_s_entry_group_commit(s->browse_domain_entry_group) < 0)
1195         avahi_log_warn("Failed to commit browse domain entry group: %s", avahi_strerror(s->error));
1196 }
1197
1198 static void register_stuff(AvahiServer *s) {
1199     assert(s);
1200
1201     server_set_state(s, AVAHI_SERVER_REGISTERING);
1202     s->n_host_rr_pending ++; /** Make sure that the state isn't changed tp AVAHI_SERVER_RUNNING too early */
1203
1204     register_hinfo(s);
1205     register_browse_domain(s);
1206     avahi_interface_monitor_update_rrs(s->monitor, 0);
1207
1208     s->n_host_rr_pending --;
1209
1210     if (s->n_host_rr_pending == 0)
1211         server_set_state(s, AVAHI_SERVER_RUNNING);
1212 }
1213
1214 static void update_fqdn(AvahiServer *s) {
1215     char *n;
1216
1217     assert(s);
1218     assert(s->host_name);
1219     assert(s->domain_name);
1220
1221     if (!(n = avahi_strdup_printf("%s.%s", s->host_name, s->domain_name)))
1222         return; /* OOM */
1223
1224     avahi_free(s->host_name_fqdn);
1225     s->host_name_fqdn = n;
1226 }
1227
1228 int avahi_server_set_host_name(AvahiServer *s, const char *host_name) {
1229     assert(s);
1230     assert(host_name);
1231
1232     if (host_name && !avahi_is_valid_host_name(host_name))
1233         return avahi_server_set_errno(s, AVAHI_ERR_INVALID_HOST_NAME);
1234
1235     withdraw_host_rrs(s);
1236
1237     avahi_free(s->host_name);
1238     s->host_name = host_name ? avahi_normalize_name_strdup(host_name) : avahi_get_host_name_strdup();
1239     s->host_name[strcspn(s->host_name, ".")] = 0;
1240     update_fqdn(s);
1241
1242     register_stuff(s);
1243     return AVAHI_OK;
1244 }
1245
1246 int avahi_server_set_domain_name(AvahiServer *s, const char *domain_name) {
1247     assert(s);
1248     assert(domain_name);
1249
1250     if (domain_name && !avahi_is_valid_domain_name(domain_name))
1251         return avahi_server_set_errno(s, AVAHI_ERR_INVALID_DOMAIN_NAME);
1252
1253     withdraw_host_rrs(s);
1254
1255     avahi_free(s->domain_name);
1256     s->domain_name = domain_name ? avahi_normalize_name_strdup(domain_name) : avahi_strdup("local");
1257     update_fqdn(s);
1258
1259     register_stuff(s);
1260     return AVAHI_OK;
1261 }
1262
1263 static int valid_server_config(const AvahiServerConfig *sc) {
1264
1265     if (sc->host_name && !avahi_is_valid_host_name(sc->host_name))
1266         return AVAHI_ERR_INVALID_HOST_NAME;
1267
1268     if (sc->domain_name && !avahi_is_valid_domain_name(sc->domain_name))
1269         return AVAHI_ERR_INVALID_DOMAIN_NAME;
1270
1271     return AVAHI_OK;
1272 }
1273
1274 static int setup_sockets(AvahiServer *s) {
1275     assert(s);
1276
1277     s->fd_ipv4 = s->config.use_ipv4 ? avahi_open_socket_ipv4(s->config.disallow_other_stacks) : -1;
1278     s->fd_ipv6 = s->config.use_ipv6 ? avahi_open_socket_ipv6(s->config.disallow_other_stacks) : -1;
1279
1280     if (s->fd_ipv6 < 0 && s->fd_ipv4 < 0)
1281         return AVAHI_ERR_NO_NETWORK;
1282
1283     if (s->fd_ipv4 < 0 && s->config.use_ipv4)
1284         avahi_log_notice("Failed to create IPv4 socket, proceeding in IPv6 only mode");
1285     else if (s->fd_ipv6 < 0 && s->config.use_ipv6)
1286         avahi_log_notice("Failed to create IPv6 socket, proceeding in IPv4 only mode");
1287
1288     s->fd_legacy_unicast_ipv4 = s->fd_ipv4 >= 0 && s->config.enable_reflector ? avahi_open_unicast_socket_ipv4() : -1;
1289     s->fd_legacy_unicast_ipv6 = s->fd_ipv6 >= 0 && s->config.enable_reflector ? avahi_open_unicast_socket_ipv6() : -1;
1290
1291     s->watch_ipv4 =
1292         s->watch_ipv6 =
1293         s->watch_legacy_unicast_ipv4 =
1294         s->watch_legacy_unicast_ipv6 = NULL;
1295
1296     if (s->fd_ipv4 >= 0)
1297         s->watch_ipv4 = s->poll_api->watch_new(s->poll_api, s->fd_ipv4, AVAHI_WATCH_IN, mcast_socket_event, s);
1298     if (s->fd_ipv6 >= 0)
1299         s->watch_ipv6 = s->poll_api->watch_new(s->poll_api, s->fd_ipv6, AVAHI_WATCH_IN, mcast_socket_event, s);
1300
1301     if (s->fd_legacy_unicast_ipv4 >= 0)
1302         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);
1303     if (s->fd_legacy_unicast_ipv6 >= 0)
1304         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);
1305
1306     return 0;
1307 }
1308
1309 AvahiServer *avahi_server_new(const AvahiPoll *poll_api, const AvahiServerConfig *sc, AvahiServerCallback callback, void* userdata, int *error) {
1310     AvahiServer *s;
1311     int e;
1312
1313     if (sc && (e = valid_server_config(sc)) < 0) {
1314         if (error)
1315             *error = e;
1316         return NULL;
1317     }
1318
1319     if (!(s = avahi_new(AvahiServer, 1))) {
1320         if (error)
1321             *error = AVAHI_ERR_NO_MEMORY;
1322
1323         return NULL;
1324     }
1325
1326     s->poll_api = poll_api;
1327
1328     if (sc)
1329         avahi_server_config_copy(&s->config, sc);
1330     else
1331         avahi_server_config_init(&s->config);
1332
1333     if ((e = setup_sockets(s)) < 0) {
1334         if (error)
1335             *error = e;
1336
1337         avahi_server_config_free(&s->config);
1338         avahi_free(s);
1339
1340         return NULL;
1341     }
1342
1343     s->n_host_rr_pending = 0;
1344     s->need_entry_cleanup = 0;
1345     s->need_group_cleanup = 0;
1346     s->need_browser_cleanup = 0;
1347     s->hinfo_entry_group = NULL;
1348     s->browse_domain_entry_group = NULL;
1349     s->error = AVAHI_OK;
1350     s->state = AVAHI_SERVER_INVALID;
1351
1352     s->callback = callback;
1353     s->userdata = userdata;
1354
1355     s->time_event_queue = avahi_time_event_queue_new(poll_api);
1356
1357     s->entries_by_key = avahi_hashmap_new((AvahiHashFunc) avahi_key_hash, (AvahiEqualFunc) avahi_key_equal, NULL, NULL);
1358     AVAHI_LLIST_HEAD_INIT(AvahiEntry, s->entries);
1359     AVAHI_LLIST_HEAD_INIT(AvahiGroup, s->groups);
1360
1361     s->record_browser_hashmap = avahi_hashmap_new((AvahiHashFunc) avahi_key_hash, (AvahiEqualFunc) avahi_key_equal, NULL, NULL);
1362     AVAHI_LLIST_HEAD_INIT(AvahiSRecordBrowser, s->record_browsers);
1363     AVAHI_LLIST_HEAD_INIT(AvahiSHostNameResolver, s->host_name_resolvers);
1364     AVAHI_LLIST_HEAD_INIT(AvahiSAddressResolver, s->address_resolvers);
1365     AVAHI_LLIST_HEAD_INIT(AvahiSDomainBrowser, s->domain_browsers);
1366     AVAHI_LLIST_HEAD_INIT(AvahiSServiceTypeBrowser, s->service_type_browsers);
1367     AVAHI_LLIST_HEAD_INIT(AvahiSServiceBrowser, s->service_browsers);
1368     AVAHI_LLIST_HEAD_INIT(AvahiSServiceResolver, s->service_resolvers);
1369     AVAHI_LLIST_HEAD_INIT(AvahiSDNSServerBrowser, s->dns_server_browsers);
1370
1371     s->legacy_unicast_reflect_slots = NULL;
1372     s->legacy_unicast_reflect_id = 0;
1373
1374     s->record_list = avahi_record_list_new();
1375
1376     /* Get host name */
1377     s->host_name = s->config.host_name ? avahi_normalize_name_strdup(s->config.host_name) : avahi_get_host_name_strdup();
1378     s->host_name[strcspn(s->host_name, ".")] = 0;
1379     s->domain_name = s->config.domain_name ? avahi_normalize_name_strdup(s->config.domain_name) : avahi_strdup("local");
1380     s->host_name_fqdn = NULL;
1381     update_fqdn(s);
1382
1383     do {
1384         s->local_service_cookie = (uint32_t) rand() * (uint32_t) rand();
1385     } while (s->local_service_cookie == AVAHI_SERVICE_COOKIE_INVALID);
1386
1387     if (s->config.enable_wide_area) {
1388         s->wide_area_lookup_engine = avahi_wide_area_engine_new(s);
1389         avahi_wide_area_set_servers(s->wide_area_lookup_engine, s->config.wide_area_servers, s->config.n_wide_area_servers);
1390     } else
1391         s->wide_area_lookup_engine = NULL;
1392
1393     s->multicast_lookup_engine = avahi_multicast_lookup_engine_new(s);
1394
1395     s->monitor = avahi_interface_monitor_new(s);
1396     avahi_interface_monitor_sync(s->monitor);
1397
1398     register_localhost(s);
1399     register_stuff(s);
1400
1401     return s;
1402 }
1403
1404 void avahi_server_free(AvahiServer* s) {
1405     assert(s);
1406
1407     /* Remove all browsers */
1408
1409     while (s->dns_server_browsers)
1410         avahi_s_dns_server_browser_free(s->dns_server_browsers);
1411     while (s->host_name_resolvers)
1412         avahi_s_host_name_resolver_free(s->host_name_resolvers);
1413     while (s->address_resolvers)
1414         avahi_s_address_resolver_free(s->address_resolvers);
1415     while (s->domain_browsers)
1416         avahi_s_domain_browser_free(s->domain_browsers);
1417     while (s->service_type_browsers)
1418         avahi_s_service_type_browser_free(s->service_type_browsers);
1419     while (s->service_browsers)
1420         avahi_s_service_browser_free(s->service_browsers);
1421     while (s->service_resolvers)
1422         avahi_s_service_resolver_free(s->service_resolvers);
1423     while (s->record_browsers)
1424         avahi_s_record_browser_destroy(s->record_browsers);
1425
1426     /* Remove all locally rgeistered stuff */
1427
1428     while(s->entries)
1429         avahi_entry_free(s, s->entries);
1430
1431     avahi_interface_monitor_free(s->monitor);
1432
1433     while (s->groups)
1434         avahi_entry_group_free(s, s->groups);
1435
1436     free_slots(s);
1437
1438     avahi_hashmap_free(s->entries_by_key);
1439     avahi_record_list_free(s->record_list);
1440     avahi_hashmap_free(s->record_browser_hashmap);
1441
1442     if (s->wide_area_lookup_engine)
1443         avahi_wide_area_engine_free(s->wide_area_lookup_engine);
1444     avahi_multicast_lookup_engine_free(s->multicast_lookup_engine);
1445
1446     avahi_time_event_queue_free(s->time_event_queue);
1447
1448     /* Free watches */
1449
1450     if (s->watch_ipv4)
1451         s->poll_api->watch_free(s->watch_ipv4);
1452     if (s->watch_ipv6)
1453         s->poll_api->watch_free(s->watch_ipv6);
1454
1455     if (s->watch_legacy_unicast_ipv4)
1456         s->poll_api->watch_free(s->watch_legacy_unicast_ipv4);
1457     if (s->watch_legacy_unicast_ipv6)
1458         s->poll_api->watch_free(s->watch_legacy_unicast_ipv6);
1459
1460     /* Free sockets */
1461
1462     if (s->fd_ipv4 >= 0)
1463         close(s->fd_ipv4);
1464     if (s->fd_ipv6 >= 0)
1465         close(s->fd_ipv6);
1466
1467     if (s->fd_legacy_unicast_ipv4 >= 0)
1468         close(s->fd_legacy_unicast_ipv4);
1469     if (s->fd_legacy_unicast_ipv6 >= 0)
1470         close(s->fd_legacy_unicast_ipv6);
1471
1472     /* Free other stuff */
1473
1474     avahi_free(s->host_name);
1475     avahi_free(s->domain_name);
1476     avahi_free(s->host_name_fqdn);
1477
1478     avahi_server_config_free(&s->config);
1479
1480     avahi_free(s);
1481 }
1482
1483 const char* avahi_server_get_domain_name(AvahiServer *s) {
1484     assert(s);
1485
1486     return s->domain_name;
1487 }
1488
1489 const char* avahi_server_get_host_name(AvahiServer *s) {
1490     assert(s);
1491
1492     return s->host_name;
1493 }
1494
1495 const char* avahi_server_get_host_name_fqdn(AvahiServer *s) {
1496     assert(s);
1497
1498     return s->host_name_fqdn;
1499 }
1500
1501 void* avahi_server_get_data(AvahiServer *s) {
1502     assert(s);
1503
1504     return s->userdata;
1505 }
1506
1507 void avahi_server_set_data(AvahiServer *s, void* userdata) {
1508     assert(s);
1509
1510     s->userdata = userdata;
1511 }
1512
1513 AvahiServerState avahi_server_get_state(AvahiServer *s) {
1514     assert(s);
1515
1516     return s->state;
1517 }
1518
1519 AvahiServerConfig* avahi_server_config_init(AvahiServerConfig *c) {
1520     assert(c);
1521
1522     memset(c, 0, sizeof(AvahiServerConfig));
1523     c->use_ipv6 = 1;
1524     c->use_ipv4 = 1;
1525     c->host_name = NULL;
1526     c->domain_name = NULL;
1527     c->check_response_ttl = 0;
1528     c->publish_hinfo = 1;
1529     c->publish_addresses = 1;
1530     c->publish_workstation = 1;
1531     c->publish_domain = 1;
1532     c->use_iff_running = 0;
1533     c->enable_reflector = 0;
1534     c->reflect_ipv = 0;
1535     c->add_service_cookie = 1;
1536     c->enable_wide_area = 0;
1537     c->n_wide_area_servers = 0;
1538     c->disallow_other_stacks = 0;
1539     c->browse_domains = NULL;
1540     c->disable_publishing = 0;
1541     c->allow_point_to_point = 0;
1542
1543     return c;
1544 }
1545
1546 void avahi_server_config_free(AvahiServerConfig *c) {
1547     assert(c);
1548
1549     avahi_free(c->host_name);
1550     avahi_free(c->domain_name);
1551     avahi_string_list_free(c->browse_domains);
1552 }
1553
1554 AvahiServerConfig* avahi_server_config_copy(AvahiServerConfig *ret, const AvahiServerConfig *c) {
1555     char *d = NULL, *h = NULL;
1556     AvahiStringList *l = NULL;
1557     assert(ret);
1558     assert(c);
1559
1560     if (c->host_name)
1561         if (!(h = avahi_strdup(c->host_name)))
1562             return NULL;
1563
1564     if (c->domain_name)
1565         if (!(d = avahi_strdup(c->domain_name))) {
1566             avahi_free(h);
1567             return NULL;
1568         }
1569
1570     if (!(l = avahi_string_list_copy(c->browse_domains)) && c->browse_domains) {
1571         avahi_free(h);
1572         avahi_free(d);
1573         return NULL;
1574     }
1575
1576     *ret = *c;
1577     ret->host_name = h;
1578     ret->domain_name = d;
1579     ret->browse_domains = l;
1580
1581     return ret;
1582 }
1583
1584 int avahi_server_errno(AvahiServer *s) {
1585     assert(s);
1586
1587     return s->error;
1588 }
1589
1590 /* Just for internal use */
1591 int avahi_server_set_errno(AvahiServer *s, int error) {
1592     assert(s);
1593
1594     return s->error = error;
1595 }
1596
1597 uint32_t avahi_server_get_local_service_cookie(AvahiServer *s) {
1598     assert(s);
1599
1600     return s->local_service_cookie;
1601 }
1602
1603 static AvahiEntry *find_entry(AvahiServer *s, AvahiIfIndex interface, AvahiProtocol protocol, AvahiKey *key) {
1604     AvahiEntry *e;
1605
1606     assert(s);
1607     assert(key);
1608
1609     for (e = avahi_hashmap_lookup(s->entries_by_key, key); e; e = e->by_key_next)
1610
1611         if ((e->interface == interface || e->interface <= 0 || interface <= 0) &&
1612             (e->protocol == protocol || e->protocol == AVAHI_PROTO_UNSPEC || protocol == AVAHI_PROTO_UNSPEC) &&
1613             (!e->group || e->group->state == AVAHI_ENTRY_GROUP_ESTABLISHED || e->group->state == AVAHI_ENTRY_GROUP_REGISTERING))
1614
1615             return e;
1616
1617     return NULL;
1618 }
1619
1620 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) {
1621     AvahiKey *key = NULL;
1622     AvahiEntry *e;
1623     int ret;
1624     char n[AVAHI_DOMAIN_NAME_MAX];
1625
1626     assert(s);
1627     assert(name);
1628     assert(type);
1629     assert(ret_group);
1630
1631     AVAHI_CHECK_VALIDITY(s, AVAHI_IF_VALID(interface), AVAHI_ERR_INVALID_INTERFACE);
1632     AVAHI_CHECK_VALIDITY(s, AVAHI_PROTO_VALID(protocol), AVAHI_ERR_INVALID_PROTOCOL);
1633     AVAHI_CHECK_VALIDITY(s, avahi_is_valid_service_name(name), AVAHI_ERR_INVALID_SERVICE_NAME);
1634     AVAHI_CHECK_VALIDITY(s, avahi_is_valid_service_type_strict(type), AVAHI_ERR_INVALID_SERVICE_TYPE);
1635     AVAHI_CHECK_VALIDITY(s, !domain || avahi_is_valid_domain_name(domain), AVAHI_ERR_INVALID_DOMAIN_NAME);
1636
1637     if ((ret = avahi_service_name_join(n, sizeof(n), name, type, domain) < 0))
1638         return avahi_server_set_errno(s, ret);
1639
1640     if (!(key = avahi_key_new(n, AVAHI_DNS_CLASS_IN, AVAHI_DNS_TYPE_SRV)))
1641         return avahi_server_set_errno(s, AVAHI_ERR_NO_MEMORY);
1642
1643     e = find_entry(s, interface, protocol, key);
1644     avahi_key_unref(key);
1645
1646     if (e) {
1647         *ret_group = e->group;
1648         return AVAHI_OK;
1649     }
1650
1651     return avahi_server_set_errno(s, AVAHI_ERR_NOT_FOUND);
1652 }
1653
1654 int avahi_server_is_service_local(AvahiServer *s, AvahiIfIndex interface, AvahiProtocol protocol, const char *name) {
1655     AvahiKey *key = NULL;
1656     AvahiEntry *e;
1657
1658     assert(s);
1659     assert(name);
1660
1661     if (!s->host_name_fqdn)
1662         return 0;
1663
1664     if (!(key = avahi_key_new(name, AVAHI_DNS_CLASS_IN, AVAHI_DNS_TYPE_SRV)))
1665         return 0;
1666
1667     e = find_entry(s, interface, protocol, key);
1668     avahi_key_unref(key);
1669
1670     if (!e)
1671         return 0;
1672
1673     return avahi_domain_equal(s->host_name_fqdn, e->record->data.srv.name);
1674 }
1675
1676 int avahi_server_is_record_local(AvahiServer *s, AvahiIfIndex interface, AvahiProtocol protocol, AvahiRecord *record) {
1677     AvahiEntry *e;
1678
1679     assert(s);
1680     assert(record);
1681
1682     for (e = avahi_hashmap_lookup(s->entries_by_key, record->key); e; e = e->by_key_next)
1683
1684         if ((e->interface == interface || e->interface <= 0 || interface <= 0) &&
1685             (e->protocol == protocol || e->protocol == AVAHI_PROTO_UNSPEC || protocol == AVAHI_PROTO_UNSPEC) &&
1686             (!e->group || e->group->state == AVAHI_ENTRY_GROUP_ESTABLISHED || e->group->state == AVAHI_ENTRY_GROUP_REGISTERING) &&
1687             avahi_record_equal_no_ttl(record, e->record))
1688             return 1;
1689
1690     return 0;
1691 }
1692
1693 /** Set the wide area DNS servers */
1694 int avahi_server_set_wide_area_servers(AvahiServer *s, const AvahiAddress *a, unsigned n) {
1695     assert(s);
1696
1697     if (!s->wide_area_lookup_engine)
1698         return avahi_server_set_errno(s, AVAHI_ERR_INVALID_CONFIG);
1699
1700     avahi_wide_area_set_servers(s->wide_area_lookup_engine, a, n);
1701     return AVAHI_OK;
1702 }