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