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, AVAHI_GCC_UNUSED 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 || (g->replace_wildcards && strstr(g->name, "%h"))) {
 226
 227         avahi_free(g->chosen_name);
 228
 229         if (g->replace_wildcards)
 230             g->chosen_name = replacestr(g->name, "%h", avahi_server_get_host_name(avahi_server));
 231         else
 232             g->chosen_name = avahi_strdup(g->name);
 233
 234     }
 235
 236     if (!g->entry_group)
 237         g->entry_group = avahi_s_entry_group_new(avahi_server, entry_group_callback, g);
 238
 239     assert(avahi_s_entry_group_is_empty(g->entry_group));
 240
 241     for (s = g->services; s; s = s->services_next) {
 242         AvahiStringList *i;
 243
 244         if (avahi_server_add_service_strlst(
 245                 avahi_server,
 246                 g->entry_group,
 247                 AVAHI_IF_UNSPEC, s->protocol,
 248                 0,
 249                 g->chosen_name, s->type, s->domain_name,
 250                 s->host_name, s->port,
 251                 s->txt_records) < 0) {
 252             avahi_log_error("Failed to add service '%s' of type '%s', ignoring service group (%s): %s",
 253                             g->chosen_name, s->type, g->filename,
 254                             avahi_strerror(avahi_server_errno(avahi_server)));
 255             remove_static_service_group_from_server(g);
 256             return;
 257         }
 258
 259         for (i = s->subtypes; i; i = i->next) {
 260
 261             if (avahi_server_add_service_subtype(
 262                     avahi_server,
 263                     g->entry_group,
 264                     AVAHI_IF_UNSPEC, s->protocol,
 265                     0,
 266                     g->chosen_name, s->type, s->domain_name,
 267                     (char*) i->text) < 0) {
 268
 269                 avahi_log_error("Failed to add subtype '%s' for service '%s' of type '%s', ignoring subtype (%s): %s",
 270                                 i->text, g->chosen_name, s->type, g->filename,
 271                                 avahi_strerror(avahi_server_errno(avahi_server)));
 272             }
 273         }
 274     }
 275
 276     avahi_s_entry_group_commit(g->entry_group);
 277 }
 278
 279 static void remove_static_service_group_from_server(StaticServiceGroup *g) {
 280     assert(g);
 281
 282     if (g->entry_group)
 283         avahi_s_entry_group_reset(g->entry_group);
 284 }
 285
 286 typedef enum {
 287     XML_TAG_INVALID,
 288     XML_TAG_SERVICE_GROUP,
 289     XML_TAG_NAME,
 290     XML_TAG_SERVICE,
 291     XML_TAG_TYPE,
 292     XML_TAG_SUBTYPE,
 293     XML_TAG_DOMAIN_NAME,
 294     XML_TAG_HOST_NAME,
 295     XML_TAG_PORT,
 296     XML_TAG_TXT_RECORD
 297 } xml_tag_name;
 298
 299 struct xml_userdata {
 300     StaticServiceGroup *group;
 301     StaticService *service;
 302     xml_tag_name current_tag;
 303     int failed;
 304     char *buf;
 305 };
 306
 307 #ifndef XMLCALL
 308 #define XMLCALL
 309 #endif
 310
 311 static void XMLCALL xml_start(void *data, const char *el, const char *attr[]) {
 312     struct xml_userdata *u = data;
 313
 314     assert(u);
 315
 316     if (u->failed)
 317         return;
 318
 319     if (u->current_tag == XML_TAG_INVALID && strcmp(el, "service-group") == 0) {
 320
 321         if (attr[0])
 322             goto invalid_attr;
 323
 324         u->current_tag = XML_TAG_SERVICE_GROUP;
 325     } else if (u->current_tag == XML_TAG_SERVICE_GROUP && strcmp(el, "name") == 0) {
 326         u->current_tag = XML_TAG_NAME;
 327
 328         if (attr[0]) {
 329             if (strcmp(attr[0], "replace-wildcards") == 0)
 330                 u->group->replace_wildcards = strcmp(attr[1], "yes") == 0;
 331             else
 332                 goto invalid_attr;
 333
 334             if (attr[2])
 335                 goto invalid_attr;
 336         }
 337
 338     } else if (u->current_tag == XML_TAG_SERVICE_GROUP && strcmp(el, "service") == 0) {
 339         u->current_tag = XML_TAG_SERVICE;
 340
 341         assert(!u->service);
 342         u->service = static_service_new(u->group);
 343
 344         if (attr[0]) {
 345             if (strcmp(attr[0], "protocol") == 0) {
 346                 AvahiProtocol protocol;
 347
 348                 if (strcmp(attr[1], "ipv4") == 0) {
 349                     protocol = AVAHI_PROTO_INET;
 350                 } else if (strcmp(attr[1], "ipv6") == 0) {
 351                     protocol = AVAHI_PROTO_INET6;
 352                 } else if (strcmp(attr[1], "any") == 0) {
 353                     protocol = AVAHI_PROTO_UNSPEC;
 354                 } else {
 355                     avahi_log_error("%s: parse failure: invalid protocol specification \"%s\".", u->group->filename, attr[1]);
 356                     u->failed = 1;
 357                     return;
 358                 }
 359
 360                 u->service->protocol = protocol;
 361             } else
 362                 goto invalid_attr;
 363
 364             if (attr[2])
 365                 goto invalid_attr;
 366         }
 367
 368     } else if (u->current_tag == XML_TAG_SERVICE && strcmp(el, "type") == 0) {
 369         if (attr[0])
 370             goto invalid_attr;
 371
 372         u->current_tag = XML_TAG_TYPE;
 373     } else if (u->current_tag == XML_TAG_SERVICE && strcmp(el, "subtype") == 0) {
 374         if (attr[0])
 375             goto invalid_attr;
 376
 377         u->current_tag = XML_TAG_SUBTYPE;
 378     } else if (u->current_tag == XML_TAG_SERVICE && strcmp(el, "domain-name") == 0) {
 379         if (attr[0])
 380             goto invalid_attr;
 381
 382         u->current_tag = XML_TAG_DOMAIN_NAME;
 383     } else if (u->current_tag == XML_TAG_SERVICE && strcmp(el, "host-name") == 0) {
 384         if (attr[0])
 385             goto invalid_attr;
 386
 387         u->current_tag = XML_TAG_HOST_NAME;
 388     } else if (u->current_tag == XML_TAG_SERVICE && strcmp(el, "port") == 0) {
 389         if (attr[0])
 390             goto invalid_attr;
 391
 392         u->current_tag = XML_TAG_PORT;
 393     } else if (u->current_tag == XML_TAG_SERVICE && strcmp(el, "txt-record") == 0) {
 394         if (attr[0])
 395             goto invalid_attr;
 396
 397         u->current_tag = XML_TAG_TXT_RECORD;
 398     } else {
 399         avahi_log_error("%s: parse failure: didn't expect element <%s>.", u->group->filename, el);
 400         u->failed = 1;
 401     }
 402
 403     return;
 404
 405 invalid_attr:
 406     avahi_log_error("%s: parse failure: invalid attribute for element <%s>.", u->group->filename, el);
 407     u->failed = 1;
 408     return;
 409 }
 410
 411 static void XMLCALL xml_end(void *data, AVAHI_GCC_UNUSED const char *el) {
 412     struct xml_userdata *u = data;
 413     assert(u);
 414
 415     if (u->failed)
 416         return;
 417
 418     switch (u->current_tag) {
 419         case XML_TAG_SERVICE_GROUP:
 420
 421             if (!u->group->name || !u->group->services) {
 422                 avahi_log_error("%s: parse failure: service group incomplete.", u->group->filename);
 423                 u->failed = 1;
 424                 return;
 425             }
 426
 427             u->current_tag = XML_TAG_INVALID;
 428             break;
 429
 430         case XML_TAG_SERVICE:
 431
 432             if (!u->service->type) {
 433                 avahi_log_error("%s: parse failure: service incomplete.", u->group->filename);
 434                 u->failed = 1;
 435                 return;
 436             }
 437
 438             u->service = NULL;
 439             u->current_tag = XML_TAG_SERVICE_GROUP;
 440             break;
 441
 442         case XML_TAG_NAME:
 443             u->current_tag = XML_TAG_SERVICE_GROUP;
 444             break;
 445
 446         case XML_TAG_PORT: {
 447             int p;
 448             assert(u->service);
 449
 450             p = u->buf ? atoi(u->buf) : 0;
 451
 452             if (p < 0 || p > 0xFFFF) {
 453                 avahi_log_error("%s: parse failure: invalid port specification \"%s\".", u->group->filename, u->buf);
 454                 u->failed = 1;
 455                 return;
 456             }
 457
 458             u->service->port = (uint16_t) p;
 459
 460             u->current_tag = XML_TAG_SERVICE;
 461             break;
 462         }
 463
 464         case XML_TAG_TXT_RECORD: {
 465             assert(u->service);
 466
 467             u->service->txt_records = avahi_string_list_add(u->service->txt_records, u->buf ? u->buf : "");
 468             u->current_tag = XML_TAG_SERVICE;
 469             break;
 470         }
 471
 472         case XML_TAG_SUBTYPE: {
 473             assert(u->service);
 474
 475             u->service->subtypes = avahi_string_list_add(u->service->subtypes, u->buf ? u->buf : "");
 476             u->current_tag = XML_TAG_SERVICE;
 477             break;
 478         }
 479
 480         case XML_TAG_TYPE:
 481         case XML_TAG_DOMAIN_NAME:
 482         case XML_TAG_HOST_NAME:
 483             u->current_tag = XML_TAG_SERVICE;
 484             break;
 485
 486         case XML_TAG_INVALID:
 487             ;
 488     }
 489
 490     avahi_free(u->buf);
 491     u->buf = NULL;
 492 }
 493
 494 static char *append_cdata(char *t, const char *n, int length) {
 495     char *r, *k;
 496
 497     if (!length)
 498         return t;
 499
 500
 501     k = avahi_strndup(n, length);
 502
 503     if (t) {
 504         r = avahi_strdup_printf("%s%s", t, k);
 505         avahi_free(k);
 506         avahi_free(t);
 507     } else
 508         r = k;
 509
 510     return r;
 511 }
 512
 513 static void XMLCALL xml_cdata(void *data, const XML_Char *s, int len) {
 514     struct xml_userdata *u = data;
 515     assert(u);
 516
 517     if (u->failed)
 518         return;
 519
 520     switch (u->current_tag) {
 521         case XML_TAG_NAME:
 522             u->group->name = append_cdata(u->group->name, s, len);
 523             break;
 524
 525         case XML_TAG_TYPE:
 526             assert(u->service);
 527             u->service->type = append_cdata(u->service->type, s, len);
 528             break;
 529
 530         case XML_TAG_DOMAIN_NAME:
 531             assert(u->service);
 532             u->service->domain_name = append_cdata(u->service->domain_name, s, len);
 533             break;
 534
 535         case XML_TAG_HOST_NAME:
 536             assert(u->service);
 537             u->service->host_name = append_cdata(u->service->host_name, s, len);
 538             break;
 539
 540         case XML_TAG_PORT:
 541         case XML_TAG_TXT_RECORD:
 542         case XML_TAG_SUBTYPE:
 543             assert(u->service);
 544             u->buf = append_cdata(u->buf, s, len);
 545             break;
 546
 547         case XML_TAG_SERVICE_GROUP:
 548         case XML_TAG_SERVICE:
 549         case XML_TAG_INVALID:
 550             ;
 551     }
 552 }
 553
 554 static int static_service_group_load(StaticServiceGroup *g) {
 555     XML_Parser parser = NULL;
 556     int fd = -1;
 557     struct xml_userdata u;
 558     int r = -1;
 559     struct stat st;
 560     ssize_t n;
 561
 562     assert(g);
 563
 564     u.buf = NULL;
 565     u.group = g;
 566     u.service = NULL;
 567     u.current_tag = XML_TAG_INVALID;
 568     u.failed = 0;
 569
 570     /* Cleanup old data in this service group, if available */
 571     remove_static_service_group_from_server(g);
 572     while (g->services)
 573         static_service_free(g->services);
 574
 575     avahi_free(g->name);
 576     avahi_free(g->chosen_name);
 577     g->name = g->chosen_name = NULL;
 578     g->replace_wildcards = 0;
 579
 580     if (!(parser = XML_ParserCreate(NULL))) {
 581         avahi_log_error("XML_ParserCreate() failed.");
 582         goto finish;
 583     }
 584
 585     if ((fd = open(g->filename, O_RDONLY)) < 0) {
 586         avahi_log_error("open(\"%s\", O_RDONLY): %s", g->filename, strerror(errno));
 587         goto finish;
 588     }
 589
 590     if (fstat(fd, &st) < 0) {
 591         avahi_log_error("fstat(): %s", strerror(errno));
 592         goto finish;
 593     }
 594
 595     g->mtime = st.st_mtime;
 596
 597     XML_SetUserData(parser, &u);
 598
 599     XML_SetElementHandler(parser, xml_start, xml_end);
 600     XML_SetCharacterDataHandler(parser, xml_cdata);
 601
 602     do {
 603         void *buffer;
 604
 605 #define BUFSIZE (10*1024)
 606
 607         if (!(buffer = XML_GetBuffer(parser, BUFSIZE))) {
 608             avahi_log_error("XML_GetBuffer() failed.");
 609             goto finish;
 610         }
 611
 612         if ((n = read(fd, buffer, BUFSIZE)) < 0) {
 613             avahi_log_error("read(): %s\n", strerror(errno));
 614             goto finish;
 615         }
 616
 617         if (!XML_ParseBuffer(parser, n, n == 0)) {
 618             avahi_log_error("XML_ParseBuffer() failed at line %d: %s.\n", (int) XML_GetCurrentLineNumber(parser), XML_ErrorString(XML_GetErrorCode(parser)));
 619             goto finish;
 620         }
 621
 622     } while (n != 0);
 623
 624     if (!u.failed)
 625         r = 0;
 626
 627 finish:
 628
 629     if (fd >= 0)
 630         close(fd);
 631
 632     if (parser)
 633         XML_ParserFree(parser);
 634
 635     avahi_free(u.buf);
 636
 637     return r;
 638 }
 639
 640 static void load_file(char *n) {
 641     StaticServiceGroup *g;
 642     assert(n);
 643
 644     for (g = groups; g; g = g->groups_next)
 645         if (strcmp(g->filename, n) == 0)
 646             return;
 647
 648     avahi_log_info("Loading service file %s.", n);
 649
 650     g = static_service_group_new(n);
 651     if (static_service_group_load(g) < 0) {
 652         avahi_log_error("Failed to load service group file %s, ignoring.", g->filename);
 653         static_service_group_free(g);
 654     }
 655 }
 656
 657 void static_service_load(int in_chroot) {
 658     StaticServiceGroup *g, *n;
 659     glob_t globbuf;
 660     int globret;
 661     char **p;
 662
 663     for (g = groups; g; g = n) {
 664         struct stat st;
 665
 666         n = g->groups_next;
 667
 668         if (stat(g->filename, &st) < 0) {
 669
 670             if (errno == ENOENT)
 671                 avahi_log_info("Service group file %s vanished, removing services.", g->filename);
 672             else
 673                 avahi_log_warn("Failed to stat() file %s, ignoring: %s", g->filename, strerror(errno));
 674
 675             static_service_group_free(g);
 676         } else if (st.st_mtime != g->mtime) {
 677             avahi_log_info("Service group file %s changed, reloading.", g->filename);
 678
 679             if (static_service_group_load(g) < 0) {
 680                 avahi_log_warn("Failed to load service group file %s, removing service.", g->filename);
 681                 static_service_group_free(g);
 682             }
 683         }
 684     }
 685
 686     memset(&globbuf, 0, sizeof(globbuf));
 687
 688     if ((globret = glob(in_chroot ? "/services/*.service" : AVAHI_SERVICE_DIR "/*.service", GLOB_ERR, NULL, &globbuf)) != 0)
 689
 690         switch (globret) {
 691 #ifdef GLOB_NOSPACE
 692             case GLOB_NOSPACE:
 693                 avahi_log_error("Not enough memory to read service directory "AVAHI_SERVICE_DIR".");
 694                 break;
 695 #endif
 696 #ifdef GLOB_NOMATCH
 697             case GLOB_NOMATCH:
 698                 avahi_log_info("No service file found in "AVAHI_SERVICE_DIR".");
 699                 break;
 700 #endif
 701             default:
 702                 avahi_log_error("Failed to read "AVAHI_SERVICE_DIR".");
 703                 break;
 704         }
 705
 706     else {
 707         for (p = globbuf.gl_pathv; *p; p++)
 708             load_file(*p);
 709
 710         globfree(&globbuf);
 711     }
 712 }
 713
 714 void static_service_free_all(void) {
 715
 716     while (groups)
 717         static_service_group_free(groups);
 718 }
 719
 720 void static_service_add_to_server(void) {
 721     StaticServiceGroup *g;
 722
 723     for (g = groups; g; g = g->groups_next)
 724         add_static_service_group_to_server(g);
 725 }
 726
 727 void static_service_remove_from_server(void) {
 728     StaticServiceGroup *g;
 729
 730     for (g = groups; g; g = g->groups_next)
 731         remove_static_service_group_from_server(g);
 732 }