git.meshlink.io Git - catta/blob - avahi-daemon/static-services.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/stat.h>
  27 #include <glob.h>
  28 #include <limits.h>
  29 #include <string.h>
  30 #include <errno.h>
  31 #include <fcntl.h>
  32 #include <unistd.h>
  33
  34 #include <expat.h>
  35
  36 #include <avahi-common/llist.h>
  37 #include <avahi-common/malloc.h>
  38 #include <avahi-common/alternative.h>
  39 #include <avahi-common/error.h>
  40 #include <avahi-core/log.h>
  41 #include <avahi-core/publish.h>
  42
  43 #include "main.h"
  44 #include "static-services.h"
  45
  46 typedef struct StaticService StaticService;
  47 typedef struct StaticServiceGroup StaticServiceGroup;
  48
  49 struct StaticService {
  50     StaticServiceGroup *group;
  51
  52     char *type;
  53     char *domain_name;
  54     char *host_name;
  55     uint16_t port;
  56     int protocol;
  57
  58     AvahiStringList *subtypes;
  59
  60     AvahiStringList *txt_records;
  61
  62     AVAHI_LLIST_FIELDS(StaticService, services);
  63 };
  64
  65 struct StaticServiceGroup {
  66     char *filename;
  67     time_t mtime;
  68
  69     char *name, *chosen_name;
  70     int replace_wildcards;
  71
  72     AvahiSEntryGroup *entry_group;
  73     AVAHI_LLIST_HEAD(StaticService, services);
  74     AVAHI_LLIST_FIELDS(StaticServiceGroup, groups);
  75 };
  76
  77 static AVAHI_LLIST_HEAD(StaticServiceGroup, groups) = NULL;
  78
  79 static char *replacestr(const char *pattern, const char *a, const char *b) {
  80     char *r = NULL, *e, *n;
  81
  82     while ((e = strstr(pattern, a))) {
  83         char *k;
  84
  85         k = avahi_strndup(pattern, e - pattern);
  86         if (r)
  87             n = avahi_strdup_printf("%s%s%s", r, k, b);
  88         else
  89             n = avahi_strdup_printf("%s%s", k, b);
  90
  91         avahi_free(k);
  92         avahi_free(r);
  93         r = n;
  94
  95         pattern = e + strlen(a);
  96     }
  97
  98     if (!r)
  99         return avahi_strdup(pattern);
 100
 101     n = avahi_strdup_printf("%s%s", r, pattern);
 102     avahi_free(r);
 103
 104     return n;
 105 }
 106
 107 static void add_static_service_group_to_server(StaticServiceGroup *g);
 108 static void remove_static_service_group_from_server(StaticServiceGroup *g);
 109
 110 static StaticService *static_service_new(StaticServiceGroup *group) {
 111     StaticService *s;
 112
 113     assert(group);
 114     s = avahi_new(StaticService, 1);
 115     s->group = group;
 116
 117     s->type = s->host_name = s->domain_name = NULL;
 118     s->port = 0;
 119     s->protocol = AVAHI_PROTO_UNSPEC;
 120
 121     s->txt_records = NULL;
 122     s->subtypes = NULL;
 123
 124     AVAHI_LLIST_PREPEND(StaticService, services, group->services, s);
 125
 126     return s;
 127 }
 128
 129 static StaticServiceGroup *static_service_group_new(char *filename) {
 130     StaticServiceGroup *g;
 131     assert(filename);
 132
 133     g = avahi_new(StaticServiceGroup, 1);
 134     g->filename = avahi_strdup(filename);
 135     g->mtime = 0;
 136     g->name = g->chosen_name = NULL;
 137     g->replace_wildcards = 0;
 138     g->entry_group = NULL;
 139
 140     AVAHI_LLIST_HEAD_INIT(StaticService, g->services);
 141     AVAHI_LLIST_PREPEND(StaticServiceGroup, groups, groups, g);
 142
 143     return g;
 144 }
 145
 146 static void static_service_free(StaticService *s) {
 147     assert(s);
 148
 149     AVAHI_LLIST_REMOVE(StaticService, services, s->group->services, s);
 150
 151     avahi_free(s->type);
 152     avahi_free(s->host_name);
 153     avahi_free(s->domain_name);
 154
 155     avahi_string_list_free(s->txt_records);
 156     avahi_string_list_free(s->subtypes);
 157
 158     avahi_free(s);
 159 }
 160
 161 static void static_service_group_free(StaticServiceGroup *g) {
 162     assert(g);
 163
 164     if (g->entry_group)
 165         avahi_s_entry_group_free(g->entry_group);
 166
 167     while (g->services)
 168         static_service_free(g->services);
 169
 170     AVAHI_LLIST_REMOVE(StaticServiceGroup, groups, groups, g);
 171
 172     avahi_free(g->filename);
 173     avahi_free(g->name);
 174     avahi_free(g->chosen_name);
 175     avahi_free(g);
 176 }
 177
 178 static void entry_group_callback(AvahiServer *s, AvahiSEntryGroup *eg, AvahiEntryGroupState state, void* userdata) {
 179     StaticServiceGroup *g = userdata;
 180
 181     assert(s);
 182     assert(g);
 183
 184     switch (state) {
 185
 186         case AVAHI_ENTRY_GROUP_COLLISION: {
 187             char *n;
 188
 189             remove_static_service_group_from_server(g);
 190
 191             n = avahi_alternative_service_name(g->chosen_name);
 192             avahi_free(g->chosen_name);
 193             g->chosen_name = n;
 194
 195             avahi_log_notice("Service name conflict for \"%s\" (%s), retrying with \"%s\".", g->name, g->filename, g->chosen_name);
 196
 197             add_static_service_group_to_server(g);
 198             break;
 199         }
 200
 201         case AVAHI_ENTRY_GROUP_ESTABLISHED:
 202             avahi_log_info("Service \"%s\" (%s) successfully established.", g->chosen_name, g->filename);
 203             break;
 204
 205         case AVAHI_ENTRY_GROUP_FAILURE:
 206             avahi_log_warn("Failed to publish service \"%s\" (%s): %s", g->chosen_name, g->filename, avahi_strerror(avahi_server_errno(s)));
 207             remove_static_service_group_from_server(g);
 208             break;
 209
 210         case AVAHI_ENTRY_GROUP_UNCOMMITED:
 211         case AVAHI_ENTRY_GROUP_REGISTERING:
 212             ;
 213     }
 214 }
 215
 216 static void add_static_service_group_to_server(StaticServiceGroup *g) {
 217     StaticService *s;
 218
 219     assert(g);
 220
 221     if (g->entry_group && !avahi_s_entry_group_is_empty(g->entry_group))
 222         /* This service group is already registered in the server */
 223         return;
 224
 225     if (!g->chosen_name) {
 226
 227         if (g->replace_wildcards)
 228             g->chosen_name = replacestr(g->name, "%h", avahi_server_get_host_name(avahi_server));
 229         else
 230             g->chosen_name = avahi_strdup(g->name);
 231
 232     }
 233
 234     if (!g->entry_group)
 235         g->entry_group = avahi_s_entry_group_new(avahi_server, entry_group_callback, g);
 236
 237     assert(avahi_s_entry_group_is_empty(g->entry_group));
 238
 239     for (s = g->services; s; s = s->services_next) {
 240         AvahiStringList *i;
 241
 242         if (avahi_server_add_service_strlst(
 243                 avahi_server,
 244                 g->entry_group,
 245                 AVAHI_IF_UNSPEC, s->protocol,
 246                 0,
 247                 g->chosen_name, s->type, s->domain_name,
 248                 s->host_name, s->port,
 249                 s->txt_records) < 0) {
 250             avahi_log_error("Failed to add service '%s' of type '%s', ignoring service group (%s): %s",
 251                             g->chosen_name, s->type, g->filename,
 252                             avahi_strerror(avahi_server_errno(avahi_server)));
 253             remove_static_service_group_from_server(g);
 254             return;
 255         }
 256
 257         for (i = s->subtypes; i; i = i->next) {
 258
 259             if (avahi_server_add_service_subtype(
 260                     avahi_server,
 261                     g->entry_group,
 262                     AVAHI_IF_UNSPEC, s->protocol,
 263                     0,
 264                     g->chosen_name, s->type, s->domain_name,
 265                     (char*) i->text) < 0) {
 266
 267                 avahi_log_error("Failed to add subtype '%s' for service '%s' of type '%s', ignoring subtype (%s): %s",
 268                                 i->text, g->chosen_name, s->type, g->filename,
 269                                 avahi_strerror(avahi_server_errno(avahi_server)));
 270             }
 271         }
 272     }
 273
 274     avahi_s_entry_group_commit(g->entry_group);
 275 }
 276
 277 static void remove_static_service_group_from_server(StaticServiceGroup *g) {
 278     assert(g);
 279
 280     if (g->entry_group)
 281         avahi_s_entry_group_reset(g->entry_group);
 282 }
 283
 284 typedef enum {
 285     XML_TAG_INVALID,
 286     XML_TAG_SERVICE_GROUP,
 287     XML_TAG_NAME,
 288     XML_TAG_SERVICE,
 289     XML_TAG_TYPE,
 290     XML_TAG_SUBTYPE,
 291     XML_TAG_DOMAIN_NAME,
 292     XML_TAG_HOST_NAME,
 293     XML_TAG_PORT,
 294     XML_TAG_TXT_RECORD
 295 } xml_tag_name;
 296
 297 struct xml_userdata {
 298     StaticServiceGroup *group;
 299     StaticService *service;
 300     xml_tag_name current_tag;
 301     int failed;
 302     char *buf;
 303 };
 304
 305 static void XMLCALL xml_start(void *data, const char *el, const char *attr[]) {
 306     struct xml_userdata *u = data;
 307
 308     assert(u);
 309
 310     if (u->failed)
 311         return;
 312
 313     if (u->current_tag == XML_TAG_INVALID && strcmp(el, "service-group") == 0) {
 314
 315         if (attr[0])
 316             goto invalid_attr;
 317
 318         u->current_tag = XML_TAG_SERVICE_GROUP;
 319     } else if (u->current_tag == XML_TAG_SERVICE_GROUP && strcmp(el, "name") == 0) {
 320         u->current_tag = XML_TAG_NAME;
 321
 322         if (attr[0]) {
 323             if (strcmp(attr[0], "replace-wildcards") == 0)
 324                 u->group->replace_wildcards = strcmp(attr[1], "yes") == 0;
 325             else
 326                 goto invalid_attr;
 327
 328             if (attr[2])
 329                 goto invalid_attr;
 330         }
 331
 332     } else if (u->current_tag == XML_TAG_SERVICE_GROUP && strcmp(el, "service") == 0) {
 333         u->current_tag = XML_TAG_SERVICE;
 334
 335         assert(!u->service);
 336         u->service = static_service_new(u->group);
 337
 338         if (attr[0]) {
 339             if (strcmp(attr[0], "protocol") == 0) {
 340                 AvahiProtocol protocol;
 341
 342                 if (strcmp(attr[1], "ipv4") == 0) {
 343                     protocol = AVAHI_PROTO_INET;
 344                 } else if (strcmp(attr[1], "ipv6") == 0) {
 345                     protocol = AVAHI_PROTO_INET6;
 346                 } else if (strcmp(attr[1], "any") == 0) {
 347                     protocol = AVAHI_PROTO_UNSPEC;
 348                 } else {
 349                     avahi_log_error("%s: parse failure: invalid protocol specification \"%s\".", u->group->filename, attr[1]);
 350                     u->failed = 1;
 351                     return;
 352                 }
 353
 354                 u->service->protocol = protocol;
 355             } else
 356                 goto invalid_attr;
 357
 358             if (attr[2])
 359                 goto invalid_attr;
 360         }
 361
 362     } else if (u->current_tag == XML_TAG_SERVICE && strcmp(el, "type") == 0) {
 363         if (attr[0])
 364             goto invalid_attr;
 365
 366         u->current_tag = XML_TAG_TYPE;
 367     } else if (u->current_tag == XML_TAG_SERVICE && strcmp(el, "subtype") == 0) {
 368         if (attr[0])
 369             goto invalid_attr;
 370
 371         u->current_tag = XML_TAG_SUBTYPE;
 372     } else if (u->current_tag == XML_TAG_SERVICE && strcmp(el, "domain-name") == 0) {
 373         if (attr[0])
 374             goto invalid_attr;
 375
 376         u->current_tag = XML_TAG_DOMAIN_NAME;
 377     } else if (u->current_tag == XML_TAG_SERVICE && strcmp(el, "host-name") == 0) {
 378         if (attr[0])
 379             goto invalid_attr;
 380
 381         u->current_tag = XML_TAG_HOST_NAME;
 382     } else if (u->current_tag == XML_TAG_SERVICE && strcmp(el, "port") == 0) {
 383         if (attr[0])
 384             goto invalid_attr;
 385
 386         u->current_tag = XML_TAG_PORT;
 387     } else if (u->current_tag == XML_TAG_SERVICE && strcmp(el, "txt-record") == 0) {
 388         if (attr[0])
 389             goto invalid_attr;
 390
 391         u->current_tag = XML_TAG_TXT_RECORD;
 392     } else {
 393         avahi_log_error("%s: parse failure: didn't expect element <%s>.", u->group->filename, el);
 394         u->failed = 1;
 395     }
 396
 397     return;
 398
 399 invalid_attr:
 400     avahi_log_error("%s: parse failure: invalid attribute for element <%s>.", u->group->filename, el);
 401     u->failed = 1;
 402     return;
 403 }
 404
 405 static void XMLCALL xml_end(void *data, const char *el) {
 406     struct xml_userdata *u = data;
 407     assert(u);
 408
 409     if (u->failed)
 410         return;
 411
 412     switch (u->current_tag) {
 413         case XML_TAG_SERVICE_GROUP:
 414
 415             if (!u->group->name || !u->group->services) {
 416                 avahi_log_error("%s: parse failure: service group incomplete.", u->group->filename);
 417                 u->failed = 1;
 418                 return;
 419             }
 420
 421             u->current_tag = XML_TAG_INVALID;
 422             break;
 423
 424         case XML_TAG_SERVICE:
 425
 426             if (!u->service->type) {
 427                 avahi_log_error("%s: parse failure: service incomplete.", u->group->filename);
 428                 u->failed = 1;
 429                 return;
 430             }
 431
 432             u->service = NULL;
 433             u->current_tag = XML_TAG_SERVICE_GROUP;
 434             break;
 435
 436         case XML_TAG_NAME:
 437             u->current_tag = XML_TAG_SERVICE_GROUP;
 438             break;
 439
 440         case XML_TAG_PORT: {
 441             int p;
 442             assert(u->service);
 443
 444             p = u->buf ? atoi(u->buf) : 0;
 445
 446             if (p < 0 || p > 0xFFFF) {
 447                 avahi_log_error("%s: parse failure: invalid port specification \"%s\".", u->group->filename, u->buf);
 448                 u->failed = 1;
 449                 return;
 450             }
 451
 452             u->service->port = (uint16_t) p;
 453
 454             u->current_tag = XML_TAG_SERVICE;
 455             break;
 456         }
 457
 458         case XML_TAG_TXT_RECORD: {
 459             assert(u->service);
 460
 461             u->service->txt_records = avahi_string_list_add(u->service->txt_records, u->buf ? u->buf : "");
 462             u->current_tag = XML_TAG_SERVICE;
 463             break;
 464         }
 465
 466         case XML_TAG_SUBTYPE: {
 467             assert(u->service);
 468
 469             u->service->subtypes = avahi_string_list_add(u->service->subtypes, u->buf ? u->buf : "");
 470             u->current_tag = XML_TAG_SERVICE;
 471             break;
 472         }
 473
 474         case XML_TAG_TYPE:
 475         case XML_TAG_DOMAIN_NAME:
 476         case XML_TAG_HOST_NAME:
 477             u->current_tag = XML_TAG_SERVICE;
 478             break;
 479
 480         case XML_TAG_INVALID:
 481             ;
 482     }
 483
 484     avahi_free(u->buf);
 485     u->buf = NULL;
 486 }
 487
 488 static char *append_cdata(char *t, const char *n, int length) {
 489     char *r, *k;
 490
 491     if (!length)
 492         return t;
 493
 494
 495     k = avahi_strndup(n, length);
 496
 497     if (t) {
 498         r = avahi_strdup_printf("%s%s", t, k);
 499         avahi_free(k);
 500         avahi_free(t);
 501     } else
 502         r = k;
 503
 504     return r;
 505 }
 506
 507 static void XMLCALL xml_cdata(void *data, const XML_Char *s, int len) {
 508     struct xml_userdata *u = data;
 509     assert(u);
 510
 511     if (u->failed)
 512         return;
 513
 514     switch (u->current_tag) {
 515         case XML_TAG_NAME:
 516             u->group->name = append_cdata(u->group->name, s, len);
 517             break;
 518
 519         case XML_TAG_TYPE:
 520             assert(u->service);
 521             u->service->type = append_cdata(u->service->type, s, len);
 522             break;
 523
 524         case XML_TAG_DOMAIN_NAME:
 525             assert(u->service);
 526             u->service->domain_name = append_cdata(u->service->domain_name, s, len);
 527             break;
 528
 529         case XML_TAG_HOST_NAME:
 530             assert(u->service);
 531             u->service->host_name = append_cdata(u->service->host_name, s, len);
 532             break;
 533
 534         case XML_TAG_PORT:
 535         case XML_TAG_TXT_RECORD:
 536         case XML_TAG_SUBTYPE:
 537             assert(u->service);
 538             u->buf = append_cdata(u->buf, s, len);
 539             break;
 540
 541         case XML_TAG_SERVICE_GROUP:
 542         case XML_TAG_SERVICE:
 543         case XML_TAG_INVALID:
 544             ;
 545     }
 546 }
 547
 548 static int static_service_group_load(StaticServiceGroup *g) {
 549     XML_Parser parser = NULL;
 550     int fd = -1;
 551     struct xml_userdata u;
 552     int r = -1;
 553     struct stat st;
 554     ssize_t n;
 555
 556     assert(g);
 557
 558     u.buf = NULL;
 559     u.group = g;
 560     u.service = NULL;
 561     u.current_tag = XML_TAG_INVALID;
 562     u.failed = 0;
 563
 564     /* Cleanup old data in this service group, if available */
 565     remove_static_service_group_from_server(g);
 566     while (g->services)
 567         static_service_free(g->services);
 568
 569     avahi_free(g->name);
 570     avahi_free(g->chosen_name);
 571     g->name = g->chosen_name = NULL;
 572     g->replace_wildcards = 0;
 573
 574     if (!(parser = XML_ParserCreate(NULL))) {
 575         avahi_log_error("XML_ParserCreate() failed.");
 576         goto finish;
 577     }
 578
 579     if ((fd = open(g->filename, O_RDONLY)) < 0) {
 580         avahi_log_error("open(\"%s\", O_RDONLY): %s", g->filename, strerror(errno));
 581         goto finish;
 582     }
 583
 584     if (fstat(fd, &st) < 0) {
 585         avahi_log_error("fstat(): %s", strerror(errno));
 586         goto finish;
 587     }
 588
 589     g->mtime = st.st_mtime;
 590
 591     XML_SetUserData(parser, &u);
 592
 593     XML_SetElementHandler(parser, xml_start, xml_end);
 594     XML_SetCharacterDataHandler(parser, xml_cdata);
 595
 596     do {
 597         void *buffer;
 598
 599 #define BUFSIZE (10*1024)
 600
 601         if (!(buffer = XML_GetBuffer(parser, BUFSIZE))) {
 602             avahi_log_error("XML_GetBuffer() failed.");
 603             goto finish;
 604         }
 605
 606         if ((n = read(fd, buffer, BUFSIZE)) < 0) {
 607             avahi_log_error("read(): %s\n", strerror(errno));
 608             goto finish;
 609         }
 610
 611         if (!XML_ParseBuffer(parser, n, n == 0)) {
 612             avahi_log_error("XML_ParseBuffer() failed at line %d: %s.\n", XML_GetCurrentLineNumber(parser), XML_ErrorString(XML_GetErrorCode(parser)));
 613             goto finish;
 614         }
 615
 616     } while (n != 0);
 617
 618     if (!u.failed)
 619         r = 0;
 620
 621 finish:
 622
 623     if (fd >= 0)
 624         close(fd);
 625
 626     if (parser)
 627         XML_ParserFree(parser);
 628
 629     avahi_free(u.buf);
 630
 631     return r;
 632 }
 633
 634 static void load_file(char *n) {
 635     StaticServiceGroup *g;
 636     assert(n);
 637
 638     for (g = groups; g; g = g->groups_next)
 639         if (strcmp(g->filename, n) == 0)
 640             return;
 641
 642     avahi_log_info("Loading service file %s.", n);
 643
 644     g = static_service_group_new(n);
 645     if (static_service_group_load(g) < 0) {
 646         avahi_log_error("Failed to load service group file %s, ignoring.", g->filename);
 647         static_service_group_free(g);
 648     }
 649 }
 650
 651 void static_service_load(void) {
 652     StaticServiceGroup *g, *n;
 653     glob_t globbuf;
 654     char **p;
 655
 656     for (g = groups; g; g = n) {
 657         struct stat st;
 658
 659         n = g->groups_next;
 660
 661         if (stat(g->filename, &st) < 0) {
 662
 663             if (errno == ENOENT)
 664                 avahi_log_info("Service group file %s vanished, removing services.", g->filename);
 665             else
 666                 avahi_log_warn("Failed to stat() file %s, ignoring: %s", g->filename, strerror(errno));
 667
 668             static_service_group_free(g);
 669         } else if (st.st_mtime != g->mtime) {
 670             avahi_log_info("Service group file %s changed, reloading.", g->filename);
 671
 672             if (static_service_group_load(g) < 0) {
 673                 avahi_log_warn("Failed to load service group file %s, removing service.", g->filename);
 674                 static_service_group_free(g);
 675             }
 676         }
 677     }
 678
 679     memset(&globbuf, 0, sizeof(globbuf));
 680     if (glob(AVAHI_SERVICE_DIR "/*.service", GLOB_ERR, NULL, &globbuf) != 0)
 681         avahi_log_error("Failed to read service directory.");
 682     else {
 683         for (p = globbuf.gl_pathv; *p; p++)
 684             load_file(*p);
 685
 686         globfree(&globbuf);
 687     }
 688 }
 689
 690 void static_service_free_all(void) {
 691
 692     while (groups)
 693         static_service_group_free(groups);
 694 }
 695
 696 void static_service_add_to_server(void) {
 697     StaticServiceGroup *g;
 698
 699     for (g = groups; g; g = g->groups_next)
 700         add_static_service_group_to_server(g);
 701 }
 702
 703 void static_service_remove_from_server(void) {
 704     StaticServiceGroup *g;
 705
 706     for (g = groups; g; g = g->groups_next)
 707         remove_static_service_group_from_server(g);
 708 }