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 + 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 an UTF8 problem?)");
 583             goto fail;
 584         }
 585
 586         if (!legacy_unicast && !from_local_iface) {
 587             reflect_query(s, i, key);
 588             avahi_cache_start_poof(i->cache, key, a);
 589         }
 590
 591         if (avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_ANCOUNT) == 0 &&
 592             !(avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_FLAGS) & AVAHI_DNS_FLAG_TC))
 593             /* Allow our own queries to be suppressed by incoming
 594              * queries only when they do not include known answers */
 595             avahi_query_scheduler_incoming(i->query_scheduler, key);
 596
 597         avahi_server_prepare_matching_responses(s, i, key, unicast_response);
 598         avahi_key_unref(key);
 599     }
 600
 601     if (!legacy_unicast) {
 602
 603         /* Known Answer Suppression */
 604         for (n = avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_ANCOUNT); n > 0; n --) {
 605             AvahiRecord *record;
 606             int unique = 0;
 607
 608             if (!(record = avahi_dns_packet_consume_record(p, &unique))) {
 609                 avahi_log_warn(__FILE__": Packet too short or invalid while reading known answer record. (Maybe an UTF8 problem?)");
 610                 goto fail;
 611             }
 612
 613             avahi_response_scheduler_suppress(i->response_scheduler, record, a);
 614             avahi_record_list_drop(s->record_list, record);
 615             avahi_cache_stop_poof(i->cache, record, a);
 616
 617             avahi_record_unref(record);
 618         }
 619
 620         /* Probe record */
 621         for (n = avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_NSCOUNT); n > 0; n --) {
 622             AvahiRecord *record;
 623             int unique = 0;
 624
 625             if (!(record = avahi_dns_packet_consume_record(p, &unique))) {
 626                 avahi_log_warn(__FILE__": Packet too short or invalid while reading probe record. (Maybe an UTF8 problem?)");
 627                 goto fail;
 628             }
 629
 630             if (!avahi_key_is_pattern(record->key)) {
 631                 if (!from_local_iface)
 632                     reflect_probe(s, i, record);
 633                 incoming_probe(s, record, i);
 634             }
 635
 636             avahi_record_unref(record);
 637         }
 638     }
 639
 640     if (!avahi_record_list_is_empty(s->record_list))
 641         avahi_server_generate_response(s, i, p, a, port, legacy_unicast, is_probe);
 642
 643     return;
 644
 645 fail:
 646     avahi_record_list_flush(s->record_list);
 647 }
 648
 649 static void handle_response_packet(AvahiServer *s, AvahiDnsPacket *p, AvahiInterface *i, const AvahiAddress *a, int from_local_iface) {
 650     unsigned n;
 651
 652     assert(s);
 653     assert(p);
 654     assert(i);
 655     assert(a);
 656
 657     for (n = avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_ANCOUNT) +
 658              avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_ARCOUNT); n > 0; n--) {
 659         AvahiRecord *record;
 660         int cache_flush = 0;
 661 /*         char *txt; */
 662
 663         if (!(record = avahi_dns_packet_consume_record(p, &cache_flush))) {
 664             avahi_log_warn(__FILE__": Packet too short or invalid while reading response record. (Maybe an UTF8 problem?)");
 665             break;
 666         }
 667
 668         if (!avahi_key_is_pattern(record->key)) {
 669
 670             if (handle_conflict(s, i, record, cache_flush)) {
 671                 if (!from_local_iface)
 672                     reflect_response(s, i, record, cache_flush);
 673                 avahi_cache_update(i->cache, record, cache_flush, a);
 674                 avahi_response_scheduler_incoming(i->response_scheduler, record, cache_flush);
 675             }
 676         }
 677
 678         avahi_record_unref(record);
 679     }
 680
 681     /* If the incoming response contained a conflicting record, some
 682        records have been scheduling for sending. We need to flush them
 683        here. */
 684     if (!avahi_record_list_is_empty(s->record_list))
 685         avahi_server_generate_response(s, i, NULL, NULL, 0, 0, 1);
 686 }
 687
 688 static AvahiLegacyUnicastReflectSlot* allocate_slot(AvahiServer *s) {
 689     unsigned n, idx = (unsigned) -1;
 690     AvahiLegacyUnicastReflectSlot *slot;
 691
 692     assert(s);
 693
 694     if (!s->legacy_unicast_reflect_slots)
 695         s->legacy_unicast_reflect_slots = avahi_new0(AvahiLegacyUnicastReflectSlot*, AVAHI_LEGACY_UNICAST_REFLECT_SLOTS_MAX);
 696
 697     for (n = 0; n < AVAHI_LEGACY_UNICAST_REFLECT_SLOTS_MAX; n++, s->legacy_unicast_reflect_id++) {
 698         idx = s->legacy_unicast_reflect_id % AVAHI_LEGACY_UNICAST_REFLECT_SLOTS_MAX;
 699
 700         if (!s->legacy_unicast_reflect_slots[idx])
 701             break;
 702     }
 703
 704     if (idx == (unsigned) -1 || s->legacy_unicast_reflect_slots[idx])
 705         return NULL;
 706
 707     if (!(slot = avahi_new(AvahiLegacyUnicastReflectSlot, 1)))
 708         return NULL; /* OOM */
 709
 710     s->legacy_unicast_reflect_slots[idx] = slot;
 711     slot->id = s->legacy_unicast_reflect_id++;
 712     slot->server = s;
 713
 714     return slot;
 715 }
 716
 717 static void deallocate_slot(AvahiServer *s, AvahiLegacyUnicastReflectSlot *slot) {
 718     unsigned idx;
 719
 720     assert(s);
 721     assert(slot);
 722
 723     idx = slot->id % AVAHI_LEGACY_UNICAST_REFLECT_SLOTS_MAX;
 724
 725     assert(s->legacy_unicast_reflect_slots[idx] == slot);
 726
 727     avahi_time_event_free(slot->time_event);
 728
 729     avahi_free(slot);
 730     s->legacy_unicast_reflect_slots[idx] = NULL;
 731 }
 732
 733 static void free_slots(AvahiServer *s) {
 734     unsigned idx;
 735     assert(s);
 736
 737     if (!s->legacy_unicast_reflect_slots)
 738         return;
 739
 740     for (idx = 0; idx < AVAHI_LEGACY_UNICAST_REFLECT_SLOTS_MAX; idx ++)
 741         if (s->legacy_unicast_reflect_slots[idx])
 742             deallocate_slot(s, s->legacy_unicast_reflect_slots[idx]);
 743
 744     avahi_free(s->legacy_unicast_reflect_slots);
 745     s->legacy_unicast_reflect_slots = NULL;
 746 }
 747
 748 static AvahiLegacyUnicastReflectSlot* find_slot(AvahiServer *s, uint16_t id) {
 749     unsigned idx;
 750
 751     assert(s);
 752
 753     if (!s->legacy_unicast_reflect_slots)
 754         return NULL;
 755
 756     idx = id % AVAHI_LEGACY_UNICAST_REFLECT_SLOTS_MAX;
 757
 758     if (!s->legacy_unicast_reflect_slots[idx] || s->legacy_unicast_reflect_slots[idx]->id != id)
 759         return NULL;
 760
 761     return s->legacy_unicast_reflect_slots[idx];
 762 }
 763
 764 static void legacy_unicast_reflect_slot_timeout(AvahiTimeEvent *e, void *userdata) {
 765     AvahiLegacyUnicastReflectSlot *slot = userdata;
 766
 767     assert(e);
 768     assert(slot);
 769     assert(slot->time_event == e);
 770
 771     deallocate_slot(slot->server, slot);
 772 }
 773
 774 static void reflect_legacy_unicast_query_packet(AvahiServer *s, AvahiDnsPacket *p, AvahiInterface *i, const AvahiAddress *a, uint16_t port) {
 775     AvahiLegacyUnicastReflectSlot *slot;
 776     AvahiInterface *j;
 777
 778     assert(s);
 779     assert(p);
 780     assert(i);
 781     assert(a);
 782     assert(port > 0);
 783     assert(i->protocol == a->proto);
 784
 785     if (!s->config.enable_reflector)
 786         return;
 787
 788     /* Reflecting legacy unicast queries is a little more complicated
 789        than reflecting normal queries, since we must route the
 790        responses back to the right client. Therefore we must store
 791        some information for finding the right client contact data for
 792        response packets. In contrast to normal queries legacy
 793        unicast query and response packets are reflected untouched and
 794        are not reassembled into larger packets */
 795
 796     if (!(slot = allocate_slot(s))) {
 797         /* No slot available, we drop this legacy unicast query */
 798         avahi_log_warn("No slot available for legacy unicast reflection, dropping query packet.");
 799         return;
 800     }
 801
 802     slot->original_id = avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_ID);
 803     slot->address = *a;
 804     slot->port = port;
 805     slot->interface = i->hardware->index;
 806
 807     avahi_elapse_time(&slot->elapse_time, 2000, 0);
 808     slot->time_event = avahi_time_event_new(s->time_event_queue, &slot->elapse_time, legacy_unicast_reflect_slot_timeout, slot);
 809
 810     /* Patch the packet with our new locally generatet id */
 811     avahi_dns_packet_set_field(p, AVAHI_DNS_FIELD_ID, slot->id);
 812
 813     for (j = s->monitor->interfaces; j; j = j->interface_next)
 814         if (j->announcing &&
 815             j != i &&
 816             (s->config.reflect_ipv || j->protocol == i->protocol)) {
 817
 818             if (j->protocol == AVAHI_PROTO_INET && s->fd_legacy_unicast_ipv4 >= 0) {
 819                 avahi_send_dns_packet_ipv4(s->fd_legacy_unicast_ipv4, j->hardware->index, p, NULL, NULL, 0);
 820             } else if (j->protocol == AVAHI_PROTO_INET6 && s->fd_legacy_unicast_ipv6 >= 0)
 821                 avahi_send_dns_packet_ipv6(s->fd_legacy_unicast_ipv6, j->hardware->index, p, NULL, NULL, 0);
 822         }
 823
 824     /* Reset the id */
 825     avahi_dns_packet_set_field(p, AVAHI_DNS_FIELD_ID, slot->original_id);
 826 }
 827
 828 static int originates_from_local_legacy_unicast_socket(AvahiServer *s, const AvahiAddress *address, uint16_t port) {
 829     assert(s);
 830     assert(address);
 831     assert(port > 0);
 832
 833     if (!s->config.enable_reflector)
 834         return 0;
 835
 836     if (!avahi_address_is_local(s->monitor, address))
 837         return 0;
 838
 839     if (address->proto == AVAHI_PROTO_INET && s->fd_legacy_unicast_ipv4 >= 0) {
 840         struct sockaddr_in lsa;
 841         socklen_t l = sizeof(lsa);
 842
 843         if (getsockname(s->fd_legacy_unicast_ipv4, (struct sockaddr*) &lsa, &l) != 0)
 844             avahi_log_warn("getsockname(): %s", strerror(errno));
 845         else
 846             return lsa.sin_port == port;
 847
 848     }
 849
 850     if (address->proto == AVAHI_PROTO_INET6 && s->fd_legacy_unicast_ipv6 >= 0) {
 851         struct sockaddr_in6 lsa;
 852         socklen_t l = sizeof(lsa);
 853
 854         if (getsockname(s->fd_legacy_unicast_ipv6, (struct sockaddr*) &lsa, &l) != 0)
 855             avahi_log_warn("getsockname(): %s", strerror(errno));
 856         else
 857             return lsa.sin6_port == port;
 858     }
 859
 860     return 0;
 861 }
 862
 863 static int is_mdns_mcast_address(const AvahiAddress *a) {
 864     AvahiAddress b;
 865     assert(a);
 866
 867     avahi_address_parse(a->proto == AVAHI_PROTO_INET ? AVAHI_IPV4_MCAST_GROUP : AVAHI_IPV6_MCAST_GROUP, a->proto, &b);
 868     return avahi_address_cmp(a, &b) == 0;
 869 }
 870
 871 static int originates_from_local_iface(AvahiServer *s, AvahiIfIndex iface, const AvahiAddress *a, uint16_t port) {
 872     assert(s);
 873     assert(iface != AVAHI_IF_UNSPEC);
 874     assert(a);
 875
 876     /* If it isn't the MDNS port it can't be generated by us */
 877     if (port != AVAHI_MDNS_PORT)
 878         return 0;
 879
 880     return avahi_interface_has_address(s->monitor, iface, a);
 881 }
 882
 883 static void dispatch_packet(AvahiServer *s, AvahiDnsPacket *p, const AvahiAddress *src_address, uint16_t port, const AvahiAddress *dst_address, AvahiIfIndex iface, int ttl) {
 884     AvahiInterface *i;
 885     int from_local_iface = 0;
 886
 887     assert(s);
 888     assert(p);
 889     assert(src_address);
 890     assert(dst_address);
 891     assert(iface > 0);
 892     assert(src_address->proto == dst_address->proto);
 893
 894     if (!(i = avahi_interface_monitor_get_interface(s->monitor, iface, src_address->proto)) ||
 895         !i->announcing) {
 896         avahi_log_warn("Recieved packet from invalid interface.");
 897         return;
 898     }
 899
 900     if (avahi_address_is_ipv4_in_ipv6(src_address))
 901         /* This is an IPv4 address encapsulated in IPv6, so let's ignore it. */
 902         return;
 903
 904     if (originates_from_local_legacy_unicast_socket(s, src_address, port))
 905         /* This originates from our local reflector, so let's ignore it */
 906         return;
 907
 908     /* We don't want to reflect local traffic, so we check if this packet is generated locally. */
 909     if (s->config.enable_reflector)
 910         from_local_iface = originates_from_local_iface(s, iface, src_address, port);
 911
 912     if (avahi_dns_packet_check_valid_multicast(p) < 0) {
 913         avahi_log_warn("Recieved invalid packet.");
 914         return;
 915     }
 916
 917     if (avahi_dns_packet_is_query(p)) {
 918         int legacy_unicast = 0;
 919
 920         if (avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_ARCOUNT) != 0) {
 921             avahi_log_warn("Invalid query packet.");
 922             return;
 923         }
 924
 925         if (port != AVAHI_MDNS_PORT) {
 926             /* Legacy Unicast */
 927
 928             if ((avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_ANCOUNT) != 0 ||
 929                  avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_NSCOUNT) != 0)) {
 930                 avahi_log_warn("Invalid legacy unicast query packet.");
 931                 return;
 932             }
 933
 934             legacy_unicast = 1;
 935         }
 936
 937         if (legacy_unicast)
 938             reflect_legacy_unicast_query_packet(s, p, i, src_address, port);
 939
 940         handle_query_packet(s, p, i, src_address, port, legacy_unicast, from_local_iface);
 941
 942     } else {
 943         if (port != AVAHI_MDNS_PORT) {
 944             avahi_log_warn("Recieved repsonse with invalid source port %u on interface '%s.%i'", port, i->hardware->name, i->protocol);
 945             return;
 946         }
 947
 948         if (ttl != 255 && s->config.check_response_ttl) {
 949             avahi_log_warn("Recieved response with invalid TTL %u on interface '%s.%i'.", ttl, i->hardware->name, i->protocol);
 950             return;
 951         }
 952
 953         if (!is_mdns_mcast_address(dst_address) &&
 954             !avahi_interface_address_on_link(i, src_address)) {
 955             avahi_log_warn("Received non-local response on interface '%s.%i'.", i->hardware->name, i->protocol);
 956             return;
 957         }
 958
 959         if (avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_QDCOUNT) != 0 ||
 960             avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_ANCOUNT) == 0 ||
 961             avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_NSCOUNT) != 0) {
 962             avahi_log_warn("Invalid response packet.");
 963             return;
 964         }
 965
 966         handle_response_packet(s, p, i, src_address, from_local_iface);
 967     }
 968 }
 969
 970 static void dispatch_legacy_unicast_packet(AvahiServer *s, AvahiDnsPacket *p) {
 971     AvahiInterface *j;
 972     AvahiLegacyUnicastReflectSlot *slot;
 973
 974     assert(s);
 975     assert(p);
 976
 977     if (avahi_dns_packet_check_valid(p) < 0 || avahi_dns_packet_is_query(p)) {
 978         avahi_log_warn("Recieved invalid packet.");
 979         return;
 980     }
 981
 982     if (!(slot = find_slot(s, avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_ID)))) {
 983         avahi_log_warn("Recieved legacy unicast response with unknown id");
 984         return;
 985     }
 986
 987     if (!(j = avahi_interface_monitor_get_interface(s->monitor, slot->interface, slot->address.proto)) ||
 988         !j->announcing)
 989         return;
 990
 991     /* Patch the original ID into this response */
 992     avahi_dns_packet_set_field(p, AVAHI_DNS_FIELD_ID, slot->original_id);
 993
 994     /* Forward the response to the correct client */
 995     avahi_interface_send_packet_unicast(j, p, &slot->address, slot->port);
 996
 997     /* Undo changes to packet */
 998     avahi_dns_packet_set_field(p, AVAHI_DNS_FIELD_ID, slot->id);
 999 }
1000
1001 static void cleanup_dead(AvahiServer *s) {
1002     assert(s);
1003
1004     avahi_cleanup_dead_entries(s);
1005     avahi_browser_cleanup(s);
1006 }
1007
1008 static void mcast_socket_event(AvahiWatch *w, int fd, AvahiWatchEvent events, void *userdata) {
1009     AvahiServer *s = userdata;
1010     AvahiAddress dest, src;
1011     AvahiDnsPacket *p = NULL;
1012     AvahiIfIndex iface;
1013     uint16_t port;
1014     uint8_t ttl;
1015
1016     assert(w);
1017     assert(fd >= 0);
1018     assert(events & AVAHI_WATCH_IN);
1019
1020     if (fd == s->fd_ipv4) {
1021         dest.proto = src.proto = AVAHI_PROTO_INET;
1022         p = avahi_recv_dns_packet_ipv4(s->fd_ipv4, &src.data.ipv4, &port, &dest.data.ipv4, &iface, &ttl);
1023     } else {
1024         assert(fd == s->fd_ipv6);
1025         dest.proto = src.proto = AVAHI_PROTO_INET6;
1026         p = avahi_recv_dns_packet_ipv6(s->fd_ipv6, &src.data.ipv6, &port, &dest.data.ipv6, &iface, &ttl);
1027     }
1028
1029     if (p) {
1030         if (iface == AVAHI_IF_UNSPEC)
1031             iface = avahi_find_interface_for_address(s->monitor, &dest);
1032
1033         if (iface != AVAHI_IF_UNSPEC)
1034             dispatch_packet(s, p, &src, port, &dest, iface, ttl);
1035         else
1036             avahi_log_error("Incoming packet recieved on address that isn't local.");
1037
1038         avahi_dns_packet_free(p);
1039
1040         cleanup_dead(s);
1041     }
1042 }
1043
1044 static void legacy_unicast_socket_event(AvahiWatch *w, int fd, AvahiWatchEvent events, void *userdata) {
1045     AvahiServer *s = userdata;
1046     AvahiDnsPacket *p = NULL;
1047
1048     assert(w);
1049     assert(fd >= 0);
1050     assert(events & AVAHI_WATCH_IN);
1051
1052     if (fd == s->fd_legacy_unicast_ipv4)
1053         p = avahi_recv_dns_packet_ipv4(s->fd_legacy_unicast_ipv4, NULL, NULL, NULL, NULL, NULL);
1054     else {
1055         assert(fd == s->fd_legacy_unicast_ipv6);
1056         p = avahi_recv_dns_packet_ipv6(s->fd_legacy_unicast_ipv6, NULL, NULL, NULL, NULL, NULL);
1057     }
1058
1059     if (p) {
1060         dispatch_legacy_unicast_packet(s, p);
1061         avahi_dns_packet_free(p);
1062
1063         cleanup_dead(s);
1064     }
1065 }
1066
1067 static void server_set_state(AvahiServer *s, AvahiServerState state) {
1068     assert(s);
1069
1070     if (s->state == state)
1071         return;
1072
1073     s->state = state;
1074
1075     avahi_interface_monitor_update_rrs(s->monitor, 0);
1076
1077     if (s->callback)
1078         s->callback(s, state, s->userdata);
1079 }
1080
1081 static void withdraw_host_rrs(AvahiServer *s) {
1082     assert(s);
1083
1084     if (s->hinfo_entry_group)
1085         avahi_s_entry_group_reset(s->hinfo_entry_group);
1086
1087     if (s->browse_domain_entry_group)
1088         avahi_s_entry_group_reset(s->browse_domain_entry_group);
1089
1090     avahi_interface_monitor_update_rrs(s->monitor, 1);
1091     s->n_host_rr_pending = 0;
1092 }
1093
1094 void avahi_server_decrease_host_rr_pending(AvahiServer *s) {
1095     assert(s);
1096
1097     assert(s->n_host_rr_pending > 0);
1098
1099     if (--s->n_host_rr_pending == 0)
1100         server_set_state(s, AVAHI_SERVER_RUNNING);
1101 }
1102
1103 void avahi_host_rr_entry_group_callback(AvahiServer *s, AvahiSEntryGroup *g, AvahiEntryGroupState state, AVAHI_GCC_UNUSED void *userdata) {
1104     assert(s);
1105     assert(g);
1106
1107     if (state == AVAHI_ENTRY_GROUP_REGISTERING &&
1108         s->state == AVAHI_SERVER_REGISTERING)
1109         s->n_host_rr_pending ++;
1110
1111     else if (state == AVAHI_ENTRY_GROUP_COLLISION &&
1112         (s->state == AVAHI_SERVER_REGISTERING || s->state == AVAHI_SERVER_RUNNING)) {
1113         withdraw_host_rrs(s);
1114         server_set_state(s, AVAHI_SERVER_COLLISION);
1115
1116     } else if (state == AVAHI_ENTRY_GROUP_ESTABLISHED &&
1117                s->state == AVAHI_SERVER_REGISTERING)
1118         avahi_server_decrease_host_rr_pending(s);
1119 }
1120
1121 static void register_hinfo(AvahiServer *s) {
1122     struct utsname utsname;
1123     AvahiRecord *r;
1124
1125     assert(s);
1126
1127     if (!s->config.publish_hinfo)
1128         return;
1129
1130     if (s->hinfo_entry_group)
1131         assert(avahi_s_entry_group_is_empty(s->hinfo_entry_group));
1132     else
1133         s->hinfo_entry_group = avahi_s_entry_group_new(s, avahi_host_rr_entry_group_callback, NULL);
1134
1135     if (!s->hinfo_entry_group) {
1136         avahi_log_warn("Failed to create HINFO entry group: %s", avahi_strerror(s->error));
1137         return;
1138     }
1139
1140     /* Fill in HINFO rr */
1141     if ((r = avahi_record_new_full(s->host_name_fqdn, AVAHI_DNS_CLASS_IN, AVAHI_DNS_TYPE_HINFO, AVAHI_DEFAULT_TTL_HOST_NAME))) {
1142
1143         if (uname(&utsname) < 0)
1144             avahi_log_warn("uname() failed: %s\n", avahi_strerror(errno));
1145         else {
1146
1147             r->data.hinfo.cpu = avahi_strdup(avahi_strup(utsname.machine));
1148             r->data.hinfo.os = avahi_strdup(avahi_strup(utsname.sysname));
1149
1150             avahi_log_info("Registering HINFO record with values '%s'/'%s'.", r->data.hinfo.cpu, r->data.hinfo.os);
1151
1152             if (avahi_server_add(s, s->hinfo_entry_group, AVAHI_IF_UNSPEC, AVAHI_PROTO_UNSPEC, AVAHI_PUBLISH_UNIQUE, r) < 0) {
1153                 avahi_log_warn("Failed to add HINFO RR: %s", avahi_strerror(s->error));
1154                 return;
1155             }
1156         }
1157
1158         avahi_record_unref(r);
1159     }
1160
1161     if (avahi_s_entry_group_commit(s->hinfo_entry_group) < 0)
1162         avahi_log_warn("Failed to commit HINFO entry group: %s", avahi_strerror(s->error));
1163
1164 }
1165
1166 static void register_localhost(AvahiServer *s) {
1167     AvahiAddress a;
1168     assert(s);
1169
1170     /* Add localhost entries */
1171     avahi_address_parse("127.0.0.1", AVAHI_PROTO_INET, &a);
1172     avahi_server_add_address(s, NULL, AVAHI_IF_UNSPEC, AVAHI_PROTO_UNSPEC, AVAHI_PUBLISH_NO_PROBE|AVAHI_PUBLISH_NO_ANNOUNCE, "localhost", &a);
1173
1174     avahi_address_parse("::1", AVAHI_PROTO_INET6, &a);
1175     avahi_server_add_address(s, NULL, AVAHI_IF_UNSPEC, AVAHI_PROTO_UNSPEC, AVAHI_PUBLISH_NO_PROBE|AVAHI_PUBLISH_NO_ANNOUNCE, "ip6-localhost", &a);
1176 }
1177
1178 static void register_browse_domain(AvahiServer *s) {
1179     assert(s);
1180
1181     if (!s->config.publish_domain)
1182         return;
1183
1184     if (avahi_domain_equal(s->domain_name, "local"))
1185         return;
1186
1187     if (s->browse_domain_entry_group)
1188         assert(avahi_s_entry_group_is_empty(s->browse_domain_entry_group));
1189     else
1190         s->browse_domain_entry_group = avahi_s_entry_group_new(s, NULL, NULL);
1191
1192     if (!s->browse_domain_entry_group) {
1193         avahi_log_warn("Failed to create browse domain entry group: %s", avahi_strerror(s->error));
1194         return;
1195     }
1196
1197     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) {
1198         avahi_log_warn("Failed to add browse domain RR: %s", avahi_strerror(s->error));
1199         return;
1200     }
1201
1202     if (avahi_s_entry_group_commit(s->browse_domain_entry_group) < 0)
1203         avahi_log_warn("Failed to commit browse domain entry group: %s", avahi_strerror(s->error));
1204 }
1205
1206 static void register_stuff(AvahiServer *s) {
1207     assert(s);
1208
1209     server_set_state(s, AVAHI_SERVER_REGISTERING);
1210     s->n_host_rr_pending ++; /** Make sure that the state isn't changed tp AVAHI_SERVER_RUNNING too early */
1211
1212     register_hinfo(s);
1213     register_browse_domain(s);
1214     avahi_interface_monitor_update_rrs(s->monitor, 0);
1215
1216     s->n_host_rr_pending --;
1217
1218     if (s->n_host_rr_pending == 0)
1219         server_set_state(s, AVAHI_SERVER_RUNNING);
1220 }
1221
1222 static void update_fqdn(AvahiServer *s) {
1223     char *n;
1224
1225     assert(s);
1226     assert(s->host_name);
1227     assert(s->domain_name);
1228
1229     if (!(n = avahi_strdup_printf("%s.%s", s->host_name, s->domain_name)))
1230         return; /* OOM */
1231
1232     avahi_free(s->host_name_fqdn);
1233     s->host_name_fqdn = n;
1234 }
1235
1236 int avahi_server_set_host_name(AvahiServer *s, const char *host_name) {
1237     char *hn = NULL;
1238     assert(s);
1239
1240     AVAHI_CHECK_VALIDITY(s, !host_name || avahi_is_valid_host_name(host_name), AVAHI_ERR_INVALID_HOST_NAME);
1241
1242     if (!host_name) {
1243         hn = avahi_get_host_name_strdup();
1244         hn[strcspn(hn, ".")] = 0;
1245         host_name = hn;
1246     }
1247
1248     if (avahi_domain_equal(s->host_name, host_name) && s->state != AVAHI_SERVER_COLLISION) {
1249         avahi_free(hn);
1250         return avahi_server_set_errno(s, AVAHI_ERR_NO_CHANGE);
1251     }
1252
1253     withdraw_host_rrs(s);
1254
1255     avahi_free(s->host_name);
1256     s->host_name = hn ? hn : avahi_strdup(host_name);
1257
1258     update_fqdn(s);
1259
1260     register_stuff(s);
1261     return AVAHI_OK;
1262 }
1263
1264 int avahi_server_set_domain_name(AvahiServer *s, const char *domain_name) {
1265     char *dn = NULL;
1266     assert(s);
1267
1268     AVAHI_CHECK_VALIDITY(s, !domain_name || avahi_is_valid_domain_name(domain_name), AVAHI_ERR_INVALID_DOMAIN_NAME);
1269
1270     if (!domain_name) {
1271         dn = avahi_strdup("local");
1272         domain_name = dn;
1273     }
1274
1275     if (avahi_domain_equal(s->domain_name, domain_name)) {
1276         avahi_free(dn);
1277         return avahi_server_set_errno(s, AVAHI_ERR_NO_CHANGE);
1278     }
1279
1280     withdraw_host_rrs(s);
1281
1282     avahi_free(s->domain_name);
1283     s->domain_name = avahi_normalize_name_strdup(domain_name);
1284     update_fqdn(s);
1285
1286     register_stuff(s);
1287
1288     avahi_free(dn);
1289     return AVAHI_OK;
1290 }
1291
1292 static int valid_server_config(const AvahiServerConfig *sc) {
1293
1294     if (sc->host_name && !avahi_is_valid_host_name(sc->host_name))
1295         return AVAHI_ERR_INVALID_HOST_NAME;
1296
1297     if (sc->domain_name && !avahi_is_valid_domain_name(sc->domain_name))
1298         return AVAHI_ERR_INVALID_DOMAIN_NAME;
1299
1300     return AVAHI_OK;
1301 }
1302
1303 static int setup_sockets(AvahiServer *s) {
1304     assert(s);
1305
1306     s->fd_ipv4 = s->config.use_ipv4 ? avahi_open_socket_ipv4(s->config.disallow_other_stacks) : -1;
1307     s->fd_ipv6 = s->config.use_ipv6 ? avahi_open_socket_ipv6(s->config.disallow_other_stacks) : -1;
1308
1309     if (s->fd_ipv6 < 0 && s->fd_ipv4 < 0)
1310         return AVAHI_ERR_NO_NETWORK;
1311
1312     if (s->fd_ipv4 < 0 && s->config.use_ipv4)
1313         avahi_log_notice("Failed to create IPv4 socket, proceeding in IPv6 only mode");
1314     else if (s->fd_ipv6 < 0 && s->config.use_ipv6)
1315         avahi_log_notice("Failed to create IPv6 socket, proceeding in IPv4 only mode");
1316
1317     s->fd_legacy_unicast_ipv4 = s->fd_ipv4 >= 0 && s->config.enable_reflector ? avahi_open_unicast_socket_ipv4() : -1;
1318     s->fd_legacy_unicast_ipv6 = s->fd_ipv6 >= 0 && s->config.enable_reflector ? avahi_open_unicast_socket_ipv6() : -1;
1319
1320     s->watch_ipv4 =
1321         s->watch_ipv6 =
1322         s->watch_legacy_unicast_ipv4 =
1323         s->watch_legacy_unicast_ipv6 = NULL;
1324
1325     if (s->fd_ipv4 >= 0)
1326         s->watch_ipv4 = s->poll_api->watch_new(s->poll_api, s->fd_ipv4, AVAHI_WATCH_IN, mcast_socket_event, s);
1327     if (s->fd_ipv6 >= 0)
1328         s->watch_ipv6 = s->poll_api->watch_new(s->poll_api, s->fd_ipv6, AVAHI_WATCH_IN, mcast_socket_event, s);
1329
1330     if (s->fd_legacy_unicast_ipv4 >= 0)
1331         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);
1332     if (s->fd_legacy_unicast_ipv6 >= 0)
1333         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);
1334
1335     return 0;
1336 }
1337
1338 AvahiServer *avahi_server_new(const AvahiPoll *poll_api, const AvahiServerConfig *sc, AvahiServerCallback callback, void* userdata, int *error) {
1339     AvahiServer *s;
1340     int e;
1341
1342     if (sc && (e = valid_server_config(sc)) < 0) {
1343         if (error)
1344             *error = e;
1345         return NULL;
1346     }
1347
1348     if (!(s = avahi_new(AvahiServer, 1))) {
1349         if (error)
1350             *error = AVAHI_ERR_NO_MEMORY;
1351
1352         return NULL;
1353     }
1354
1355     s->poll_api = poll_api;
1356
1357     if (sc)
1358         avahi_server_config_copy(&s->config, sc);
1359     else
1360         avahi_server_config_init(&s->config);
1361
1362     if ((e = setup_sockets(s)) < 0) {
1363         if (error)
1364             *error = e;
1365
1366         avahi_server_config_free(&s->config);
1367         avahi_free(s);
1368
1369         return NULL;
1370     }
1371
1372     s->n_host_rr_pending = 0;
1373     s->need_entry_cleanup = 0;
1374     s->need_group_cleanup = 0;
1375     s->need_browser_cleanup = 0;
1376     s->hinfo_entry_group = NULL;
1377     s->browse_domain_entry_group = NULL;
1378     s->error = AVAHI_OK;
1379     s->state = AVAHI_SERVER_INVALID;
1380
1381     s->callback = callback;
1382     s->userdata = userdata;
1383
1384     s->time_event_queue = avahi_time_event_queue_new(poll_api);
1385
1386     s->entries_by_key = avahi_hashmap_new((AvahiHashFunc) avahi_key_hash, (AvahiEqualFunc) avahi_key_equal, NULL, NULL);
1387     AVAHI_LLIST_HEAD_INIT(AvahiEntry, s->entries);
1388     AVAHI_LLIST_HEAD_INIT(AvahiGroup, s->groups);
1389
1390     s->record_browser_hashmap = avahi_hashmap_new((AvahiHashFunc) avahi_key_hash, (AvahiEqualFunc) avahi_key_equal, NULL, NULL);
1391     AVAHI_LLIST_HEAD_INIT(AvahiSRecordBrowser, s->record_browsers);
1392     AVAHI_LLIST_HEAD_INIT(AvahiSHostNameResolver, s->host_name_resolvers);
1393     AVAHI_LLIST_HEAD_INIT(AvahiSAddressResolver, s->address_resolvers);
1394     AVAHI_LLIST_HEAD_INIT(AvahiSDomainBrowser, s->domain_browsers);
1395     AVAHI_LLIST_HEAD_INIT(AvahiSServiceTypeBrowser, s->service_type_browsers);
1396     AVAHI_LLIST_HEAD_INIT(AvahiSServiceBrowser, s->service_browsers);
1397     AVAHI_LLIST_HEAD_INIT(AvahiSServiceResolver, s->service_resolvers);
1398     AVAHI_LLIST_HEAD_INIT(AvahiSDNSServerBrowser, s->dns_server_browsers);
1399
1400     s->legacy_unicast_reflect_slots = NULL;
1401     s->legacy_unicast_reflect_id = 0;
1402
1403     s->record_list = avahi_record_list_new();
1404
1405     /* Get host name */
1406     s->host_name = s->config.host_name ? avahi_normalize_name_strdup(s->config.host_name) : avahi_get_host_name_strdup();
1407     s->host_name[strcspn(s->host_name, ".")] = 0;
1408     s->domain_name = s->config.domain_name ? avahi_normalize_name_strdup(s->config.domain_name) : avahi_strdup("local");
1409     s->host_name_fqdn = NULL;
1410     update_fqdn(s);
1411
1412     do {
1413         s->local_service_cookie = (uint32_t) rand() * (uint32_t) rand();
1414     } while (s->local_service_cookie == AVAHI_SERVICE_COOKIE_INVALID);
1415
1416     if (s->config.enable_wide_area) {
1417         s->wide_area_lookup_engine = avahi_wide_area_engine_new(s);
1418         avahi_wide_area_set_servers(s->wide_area_lookup_engine, s->config.wide_area_servers, s->config.n_wide_area_servers);
1419     } else
1420         s->wide_area_lookup_engine = NULL;
1421
1422     s->multicast_lookup_engine = avahi_multicast_lookup_engine_new(s);
1423
1424     s->monitor = avahi_interface_monitor_new(s);
1425     avahi_interface_monitor_sync(s->monitor);
1426
1427     register_localhost(s);
1428     register_stuff(s);
1429
1430     return s;
1431 }
1432
1433 void avahi_server_free(AvahiServer* s) {
1434     assert(s);
1435
1436     /* Remove all browsers */
1437
1438     while (s->dns_server_browsers)
1439         avahi_s_dns_server_browser_free(s->dns_server_browsers);
1440     while (s->host_name_resolvers)
1441         avahi_s_host_name_resolver_free(s->host_name_resolvers);
1442     while (s->address_resolvers)
1443         avahi_s_address_resolver_free(s->address_resolvers);
1444     while (s->domain_browsers)
1445         avahi_s_domain_browser_free(s->domain_browsers);
1446     while (s->service_type_browsers)
1447         avahi_s_service_type_browser_free(s->service_type_browsers);
1448     while (s->service_browsers)
1449         avahi_s_service_browser_free(s->service_browsers);
1450     while (s->service_resolvers)
1451         avahi_s_service_resolver_free(s->service_resolvers);
1452     while (s->record_browsers)
1453         avahi_s_record_browser_destroy(s->record_browsers);
1454
1455     /* Remove all locally rgeistered stuff */
1456
1457     while(s->entries)
1458         avahi_entry_free(s, s->entries);
1459
1460     avahi_interface_monitor_free(s->monitor);
1461
1462     while (s->groups)
1463         avahi_entry_group_free(s, s->groups);
1464
1465     free_slots(s);
1466
1467     avahi_hashmap_free(s->entries_by_key);
1468     avahi_record_list_free(s->record_list);
1469     avahi_hashmap_free(s->record_browser_hashmap);
1470
1471     if (s->wide_area_lookup_engine)
1472         avahi_wide_area_engine_free(s->wide_area_lookup_engine);
1473     avahi_multicast_lookup_engine_free(s->multicast_lookup_engine);
1474
1475     avahi_time_event_queue_free(s->time_event_queue);
1476
1477     /* Free watches */
1478
1479     if (s->watch_ipv4)
1480         s->poll_api->watch_free(s->watch_ipv4);
1481     if (s->watch_ipv6)
1482         s->poll_api->watch_free(s->watch_ipv6);
1483
1484     if (s->watch_legacy_unicast_ipv4)
1485         s->poll_api->watch_free(s->watch_legacy_unicast_ipv4);
1486     if (s->watch_legacy_unicast_ipv6)
1487         s->poll_api->watch_free(s->watch_legacy_unicast_ipv6);
1488
1489     /* Free sockets */
1490
1491     if (s->fd_ipv4 >= 0)
1492         close(s->fd_ipv4);
1493     if (s->fd_ipv6 >= 0)
1494         close(s->fd_ipv6);
1495
1496     if (s->fd_legacy_unicast_ipv4 >= 0)
1497         close(s->fd_legacy_unicast_ipv4);
1498     if (s->fd_legacy_unicast_ipv6 >= 0)
1499         close(s->fd_legacy_unicast_ipv6);
1500
1501     /* Free other stuff */
1502
1503     avahi_free(s->host_name);
1504     avahi_free(s->domain_name);
1505     avahi_free(s->host_name_fqdn);
1506
1507     avahi_server_config_free(&s->config);
1508
1509     avahi_free(s);
1510 }
1511
1512 const char* avahi_server_get_domain_name(AvahiServer *s) {
1513     assert(s);
1514
1515     return s->domain_name;
1516 }
1517
1518 const char* avahi_server_get_host_name(AvahiServer *s) {
1519     assert(s);
1520
1521     return s->host_name;
1522 }
1523
1524 const char* avahi_server_get_host_name_fqdn(AvahiServer *s) {
1525     assert(s);
1526
1527     return s->host_name_fqdn;
1528 }
1529
1530 void* avahi_server_get_data(AvahiServer *s) {
1531     assert(s);
1532
1533     return s->userdata;
1534 }
1535
1536 void avahi_server_set_data(AvahiServer *s, void* userdata) {
1537     assert(s);
1538
1539     s->userdata = userdata;
1540 }
1541
1542 AvahiServerState avahi_server_get_state(AvahiServer *s) {
1543     assert(s);
1544
1545     return s->state;
1546 }
1547
1548 AvahiServerConfig* avahi_server_config_init(AvahiServerConfig *c) {
1549     assert(c);
1550
1551     memset(c, 0, sizeof(AvahiServerConfig));
1552     c->use_ipv6 = 1;
1553     c->use_ipv4 = 1;
1554     c->host_name = NULL;
1555     c->domain_name = NULL;
1556     c->check_response_ttl = 0;
1557     c->publish_hinfo = 1;
1558     c->publish_addresses = 1;
1559     c->publish_workstation = 1;
1560     c->publish_domain = 1;
1561     c->use_iff_running = 0;
1562     c->enable_reflector = 0;
1563     c->reflect_ipv = 0;
1564     c->add_service_cookie = 0;
1565     c->enable_wide_area = 0;
1566     c->n_wide_area_servers = 0;
1567     c->disallow_other_stacks = 0;
1568     c->browse_domains = NULL;
1569     c->disable_publishing = 0;
1570     c->allow_point_to_point = 0;
1571     c->publish_aaaa_on_ipv4 = 1;
1572     c->publish_a_on_ipv6 = 0;
1573
1574     return c;
1575 }
1576
1577 void avahi_server_config_free(AvahiServerConfig *c) {
1578     assert(c);
1579
1580     avahi_free(c->host_name);
1581     avahi_free(c->domain_name);
1582     avahi_string_list_free(c->browse_domains);
1583 }
1584
1585 AvahiServerConfig* avahi_server_config_copy(AvahiServerConfig *ret, const AvahiServerConfig *c) {
1586     char *d = NULL, *h = NULL;
1587     AvahiStringList *l = NULL;
1588     assert(ret);
1589     assert(c);
1590
1591     if (c->host_name)
1592         if (!(h = avahi_strdup(c->host_name)))
1593             return NULL;
1594
1595     if (c->domain_name)
1596         if (!(d = avahi_strdup(c->domain_name))) {
1597             avahi_free(h);
1598             return NULL;
1599         }
1600
1601     if (!(l = avahi_string_list_copy(c->browse_domains)) && c->browse_domains) {
1602         avahi_free(h);
1603         avahi_free(d);
1604         return NULL;
1605     }
1606
1607     *ret = *c;
1608     ret->host_name = h;
1609     ret->domain_name = d;
1610     ret->browse_domains = l;
1611
1612     return ret;
1613 }
1614
1615 int avahi_server_errno(AvahiServer *s) {
1616     assert(s);
1617
1618     return s->error;
1619 }
1620
1621 /* Just for internal use */
1622 int avahi_server_set_errno(AvahiServer *s, int error) {
1623     assert(s);
1624
1625     return s->error = error;
1626 }
1627
1628 uint32_t avahi_server_get_local_service_cookie(AvahiServer *s) {
1629     assert(s);
1630
1631     return s->local_service_cookie;
1632 }
1633
1634 static AvahiEntry *find_entry(AvahiServer *s, AvahiIfIndex interface, AvahiProtocol protocol, AvahiKey *key) {
1635     AvahiEntry *e;
1636
1637     assert(s);
1638     assert(key);
1639
1640     for (e = avahi_hashmap_lookup(s->entries_by_key, key); e; e = e->by_key_next)
1641
1642         if ((e->interface == interface || e->interface <= 0 || interface <= 0) &&
1643             (e->protocol == protocol || e->protocol == AVAHI_PROTO_UNSPEC || protocol == AVAHI_PROTO_UNSPEC) &&
1644             (!e->group || e->group->state == AVAHI_ENTRY_GROUP_ESTABLISHED || e->group->state == AVAHI_ENTRY_GROUP_REGISTERING))
1645
1646             return e;
1647
1648     return NULL;
1649 }
1650
1651 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) {
1652     AvahiKey *key = NULL;
1653     AvahiEntry *e;
1654     int ret;
1655     char n[AVAHI_DOMAIN_NAME_MAX];
1656
1657     assert(s);
1658     assert(name);
1659     assert(type);
1660     assert(ret_group);
1661
1662     AVAHI_CHECK_VALIDITY(s, AVAHI_IF_VALID(interface), AVAHI_ERR_INVALID_INTERFACE);
1663     AVAHI_CHECK_VALIDITY(s, AVAHI_PROTO_VALID(protocol), AVAHI_ERR_INVALID_PROTOCOL);
1664     AVAHI_CHECK_VALIDITY(s, avahi_is_valid_service_name(name), AVAHI_ERR_INVALID_SERVICE_NAME);
1665     AVAHI_CHECK_VALIDITY(s, avahi_is_valid_service_type_strict(type), AVAHI_ERR_INVALID_SERVICE_TYPE);
1666     AVAHI_CHECK_VALIDITY(s, !domain || avahi_is_valid_domain_name(domain), AVAHI_ERR_INVALID_DOMAIN_NAME);
1667
1668     if ((ret = avahi_service_name_join(n, sizeof(n), name, type, domain) < 0))
1669         return avahi_server_set_errno(s, ret);
1670
1671     if (!(key = avahi_key_new(n, AVAHI_DNS_CLASS_IN, AVAHI_DNS_TYPE_SRV)))
1672         return avahi_server_set_errno(s, AVAHI_ERR_NO_MEMORY);
1673
1674     e = find_entry(s, interface, protocol, key);
1675     avahi_key_unref(key);
1676
1677     if (e) {
1678         *ret_group = e->group;
1679         return AVAHI_OK;
1680     }
1681
1682     return avahi_server_set_errno(s, AVAHI_ERR_NOT_FOUND);
1683 }
1684
1685 int avahi_server_is_service_local(AvahiServer *s, AvahiIfIndex interface, AvahiProtocol protocol, const char *name) {
1686     AvahiKey *key = NULL;
1687     AvahiEntry *e;
1688
1689     assert(s);
1690     assert(name);
1691
1692     if (!s->host_name_fqdn)
1693         return 0;
1694
1695     if (!(key = avahi_key_new(name, AVAHI_DNS_CLASS_IN, AVAHI_DNS_TYPE_SRV)))
1696         return 0;
1697
1698     e = find_entry(s, interface, protocol, key);
1699     avahi_key_unref(key);
1700
1701     if (!e)
1702         return 0;
1703
1704     return avahi_domain_equal(s->host_name_fqdn, e->record->data.srv.name);
1705 }
1706
1707 int avahi_server_is_record_local(AvahiServer *s, AvahiIfIndex interface, AvahiProtocol protocol, AvahiRecord *record) {
1708     AvahiEntry *e;
1709
1710     assert(s);
1711     assert(record);
1712
1713     for (e = avahi_hashmap_lookup(s->entries_by_key, record->key); e; e = e->by_key_next)
1714
1715         if ((e->interface == interface || e->interface <= 0 || interface <= 0) &&
1716             (e->protocol == protocol || e->protocol == AVAHI_PROTO_UNSPEC || protocol == AVAHI_PROTO_UNSPEC) &&
1717             (!e->group || e->group->state == AVAHI_ENTRY_GROUP_ESTABLISHED || e->group->state == AVAHI_ENTRY_GROUP_REGISTERING) &&
1718             avahi_record_equal_no_ttl(record, e->record))
1719             return 1;
1720
1721     return 0;
1722 }
1723
1724 /** Set the wide area DNS servers */
1725 int avahi_server_set_wide_area_servers(AvahiServer *s, const AvahiAddress *a, unsigned n) {
1726     assert(s);
1727
1728     if (!s->wide_area_lookup_engine)
1729         return avahi_server_set_errno(s, AVAHI_ERR_INVALID_CONFIG);
1730
1731     avahi_wide_area_set_servers(s->wide_area_lookup_engine, a, n);
1732     return AVAHI_OK;
1733 }
1734
1735 const AvahiServerConfig* avahi_server_get_config(AvahiServer *s) {
1736     assert(s);
1737
1738     return &s->config;
1739 }