1 /***
2 This file is part of avahi.
3
4 avahi is free software; you can redistribute it and/or modify it
5 under the terms of the GNU Lesser General Public License as
6 published by the Free Software Foundation; either version 2.1 of the
7 License, or (at your option) any later version.
8
9 avahi is distributed in the hope that it will be useful, but WITHOUT
10 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
11 or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General
12 Public License for more details.
13
14 You should have received a copy of the GNU Lesser General Public
15 License along with avahi; if not, write to the Free Software
16 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
17 USA.
18 ***/
19
20 #ifdef HAVE_CONFIG_H
21 #include <config.h>
22 #endif
23
24 #include <sys/stat.h>
25 #include <glob.h>
26 #include <limits.h>
27 #include <string.h>
28 #include <errno.h>
29 #include <fcntl.h>
30 #include <unistd.h>
31 #include <stdlib.h>
32
33 #ifdef USE_EXPAT_H
34 #include <expat.h>
35 #endif /* USE_EXPAT_H */
36
37 #ifdef USE_BSDXML_H
38 #include <bsdxml.h>
39 #endif /* USE_BSDXML_H */
40
41 #include <avahi-common/llist.h>
42 #include "avahi-common/avahi-malloc.h"
43 #include <avahi-common/alternative.h>
44 #include <avahi-common/error.h>
45 #include <avahi-common/domain.h>
46 #include <avahi-core/log.h>
47 #include <avahi-core/publish.h>
48
49 #include "main.h"
50 #include "static-services.h"
51
52 typedef struct StaticService StaticService;
53 typedef struct StaticServiceGroup StaticServiceGroup;
54
55 struct StaticService {
56 StaticServiceGroup *group;
57
58 char *type;
59 char *domain_name;
60 char *host_name;
61 uint16_t port;
62 int protocol;
63
64 AvahiStringList *subtypes;
65
66 AvahiStringList *txt_records;
67
68 AVAHI_LLIST_FIELDS(StaticService, services);
69 };
70
71 struct StaticServiceGroup {
72 char *filename;
73 time_t mtime;
74
75 char *name, *chosen_name;
76 int replace_wildcards;
77
78 AvahiSEntryGroup *entry_group;
79 AVAHI_LLIST_HEAD(StaticService, services);
80 AVAHI_LLIST_FIELDS(StaticServiceGroup, groups);
81 };
82
83 static AVAHI_LLIST_HEAD(StaticServiceGroup, groups) = NULL;
84
replacestr(const char * pattern,const char * a,const char * b)85 static char *replacestr(const char *pattern, const char *a, const char *b) {
86 char *r = NULL, *e, *n;
87
88 while ((e = strstr(pattern, a))) {
89 char *k;
90
91 k = avahi_strndup(pattern, e - pattern);
92 if (r)
93 n = avahi_strdup_printf("%s%s%s", r, k, b);
94 else
95 n = avahi_strdup_printf("%s%s", k, b);
96
97 avahi_free(k);
98 avahi_free(r);
99 r = n;
100
101 pattern = e + strlen(a);
102 }
103
104 if (!r)
105 return avahi_strdup(pattern);
106
107 n = avahi_strdup_printf("%s%s", r, pattern);
108 avahi_free(r);
109
110 return n;
111 }
112
113 static void add_static_service_group_to_server(StaticServiceGroup *g);
114 static void remove_static_service_group_from_server(StaticServiceGroup *g);
115
static_service_new(StaticServiceGroup * group)116 static StaticService *static_service_new(StaticServiceGroup *group) {
117 StaticService *s;
118
119 assert(group);
120 s = avahi_new(StaticService, 1);
121 s->group = group;
122
123 s->type = s->host_name = s->domain_name = NULL;
124 s->port = 0;
125 s->protocol = AVAHI_PROTO_UNSPEC;
126
127 s->txt_records = NULL;
128 s->subtypes = NULL;
129
130 AVAHI_LLIST_PREPEND(StaticService, services, group->services, s);
131
132 return s;
133 }
134
static_service_group_new(char * filename)135 static StaticServiceGroup *static_service_group_new(char *filename) {
136 StaticServiceGroup *g;
137 assert(filename);
138
139 g = avahi_new(StaticServiceGroup, 1);
140 g->filename = avahi_strdup(filename);
141 g->mtime = 0;
142 g->name = g->chosen_name = NULL;
143 g->replace_wildcards = 0;
144 g->entry_group = NULL;
145
146 AVAHI_LLIST_HEAD_INIT(StaticService, g->services);
147 AVAHI_LLIST_PREPEND(StaticServiceGroup, groups, groups, g);
148
149 return g;
150 }
151
static_service_free(StaticService * s)152 static void static_service_free(StaticService *s) {
153 assert(s);
154
155 AVAHI_LLIST_REMOVE(StaticService, services, s->group->services, s);
156
157 avahi_free(s->type);
158 avahi_free(s->host_name);
159 avahi_free(s->domain_name);
160
161 avahi_string_list_free(s->txt_records);
162 avahi_string_list_free(s->subtypes);
163
164 avahi_free(s);
165 }
166
static_service_group_free(StaticServiceGroup * g)167 static void static_service_group_free(StaticServiceGroup *g) {
168 assert(g);
169
170 if (g->entry_group)
171 avahi_s_entry_group_free(g->entry_group);
172
173 while (g->services)
174 static_service_free(g->services);
175
176 AVAHI_LLIST_REMOVE(StaticServiceGroup, groups, groups, g);
177
178 avahi_free(g->filename);
179 avahi_free(g->name);
180 avahi_free(g->chosen_name);
181 avahi_free(g);
182 }
183
entry_group_callback(AvahiServer * s,AVAHI_GCC_UNUSED AvahiSEntryGroup * eg,AvahiEntryGroupState state,void * userdata)184 static void entry_group_callback(AvahiServer *s, AVAHI_GCC_UNUSED AvahiSEntryGroup *eg, AvahiEntryGroupState state, void* userdata) {
185 StaticServiceGroup *g = userdata;
186
187 assert(s);
188 assert(g);
189
190 switch (state) {
191
192 case AVAHI_ENTRY_GROUP_COLLISION: {
193 char *n;
194
195 remove_static_service_group_from_server(g);
196
197 n = avahi_alternative_service_name(g->chosen_name);
198 avahi_free(g->chosen_name);
199 g->chosen_name = n;
200
201 avahi_log_notice("Service name conflict for \"%s\" (%s), retrying with \"%s\".", g->name, g->filename, g->chosen_name);
202
203 add_static_service_group_to_server(g);
204 break;
205 }
206
207 case AVAHI_ENTRY_GROUP_ESTABLISHED:
208 avahi_log_info("Service \"%s\" (%s) successfully established.", g->chosen_name, g->filename);
209 break;
210
211 case AVAHI_ENTRY_GROUP_FAILURE:
212 avahi_log_warn("Failed to publish service \"%s\" (%s): %s", g->chosen_name, g->filename, avahi_strerror(avahi_server_errno(s)));
213 remove_static_service_group_from_server(g);
214 break;
215
216 case AVAHI_ENTRY_GROUP_UNCOMMITED:
217 case AVAHI_ENTRY_GROUP_REGISTERING:
218 ;
219 }
220 }
221
add_static_service_group_to_server(StaticServiceGroup * g)222 static void add_static_service_group_to_server(StaticServiceGroup *g) {
223 StaticService *s;
224
225 assert(g);
226
227 if (g->entry_group && !avahi_s_entry_group_is_empty(g->entry_group))
228 /* This service group is already registered in the server */
229 return;
230
231 if (!g->chosen_name || (g->replace_wildcards && strstr(g->name, "%h"))) {
232
233 avahi_free(g->chosen_name);
234
235 if (g->replace_wildcards) {
236 char label[AVAHI_LABEL_MAX];
237 const char *p;
238
239 p = avahi_server_get_host_name(avahi_server);
240 avahi_unescape_label(&p, label, sizeof(label));
241
242 g->chosen_name = replacestr(g->name, "%h", label);
243 } else
244 g->chosen_name = avahi_strdup(g->name);
245
246 }
247
248 if (!g->entry_group)
249 g->entry_group = avahi_s_entry_group_new(avahi_server, entry_group_callback, g);
250
251 assert(avahi_s_entry_group_is_empty(g->entry_group));
252
253 for (s = g->services; s; s = s->services_next) {
254 AvahiStringList *i;
255
256 if (avahi_server_add_service_strlst(
257 avahi_server,
258 g->entry_group,
259 AVAHI_IF_UNSPEC, s->protocol,
260 0,
261 g->chosen_name, s->type, s->domain_name,
262 s->host_name, s->port,
263 s->txt_records) < 0) {
264 avahi_log_error("Failed to add service '%s' of type '%s', ignoring service group (%s): %s",
265 g->chosen_name, s->type, g->filename,
266 avahi_strerror(avahi_server_errno(avahi_server)));
267 remove_static_service_group_from_server(g);
268 return;
269 }
270
271 for (i = s->subtypes; i; i = i->next) {
272
273 if (avahi_server_add_service_subtype(
274 avahi_server,
275 g->entry_group,
276 AVAHI_IF_UNSPEC, s->protocol,
277 0,
278 g->chosen_name, s->type, s->domain_name,
279 (char*) i->text) < 0) {
280
281 avahi_log_error("Failed to add subtype '%s' for service '%s' of type '%s', ignoring subtype (%s): %s",
282 i->text, g->chosen_name, s->type, g->filename,
283 avahi_strerror(avahi_server_errno(avahi_server)));
284 }
285 }
286 }
287
288 avahi_s_entry_group_commit(g->entry_group);
289 }
290
remove_static_service_group_from_server(StaticServiceGroup * g)291 static void remove_static_service_group_from_server(StaticServiceGroup *g) {
292 assert(g);
293
294 if (g->entry_group)
295 avahi_s_entry_group_reset(g->entry_group);
296 }
297
298 typedef enum {
299 XML_TAG_INVALID,
300 XML_TAG_SERVICE_GROUP,
301 XML_TAG_NAME,
302 XML_TAG_SERVICE,
303 XML_TAG_TYPE,
304 XML_TAG_SUBTYPE,
305 XML_TAG_DOMAIN_NAME,
306 XML_TAG_HOST_NAME,
307 XML_TAG_PORT,
308 XML_TAG_TXT_RECORD
309 } xml_tag_name;
310
311 struct xml_userdata {
312 StaticServiceGroup *group;
313 StaticService *service;
314 xml_tag_name current_tag;
315 int failed;
316 char *buf;
317 };
318
319 #ifndef XMLCALL
320 #define XMLCALL
321 #endif
322
xml_start(void * data,const char * el,const char * attr[])323 static void XMLCALL xml_start(void *data, const char *el, const char *attr[]) {
324 struct xml_userdata *u = data;
325
326 assert(u);
327
328 if (u->failed)
329 return;
330
331 if (u->current_tag == XML_TAG_INVALID && strcmp(el, "service-group") == 0) {
332
333 if (attr[0])
334 goto invalid_attr;
335
336 u->current_tag = XML_TAG_SERVICE_GROUP;
337 } else if (u->current_tag == XML_TAG_SERVICE_GROUP && strcmp(el, "name") == 0) {
338 u->current_tag = XML_TAG_NAME;
339
340 if (attr[0]) {
341 if (strcmp(attr[0], "replace-wildcards") == 0)
342 u->group->replace_wildcards = strcmp(attr[1], "yes") == 0;
343 else
344 goto invalid_attr;
345
346 if (attr[2])
347 goto invalid_attr;
348 }
349
350 } else if (u->current_tag == XML_TAG_SERVICE_GROUP && strcmp(el, "service") == 0) {
351 u->current_tag = XML_TAG_SERVICE;
352
353 assert(!u->service);
354 u->service = static_service_new(u->group);
355
356 if (attr[0]) {
357 if (strcmp(attr[0], "protocol") == 0) {
358 AvahiProtocol protocol;
359
360 if (strcmp(attr[1], "ipv4") == 0) {
361 protocol = AVAHI_PROTO_INET;
362 } else if (strcmp(attr[1], "ipv6") == 0) {
363 protocol = AVAHI_PROTO_INET6;
364 } else if (strcmp(attr[1], "any") == 0) {
365 protocol = AVAHI_PROTO_UNSPEC;
366 } else {
367 avahi_log_error("%s: parse failure: invalid protocol specification \"%s\".", u->group->filename, attr[1]);
368 u->failed = 1;
369 return;
370 }
371
372 u->service->protocol = protocol;
373 } else
374 goto invalid_attr;
375
376 if (attr[2])
377 goto invalid_attr;
378 }
379
380 } else if (u->current_tag == XML_TAG_SERVICE && strcmp(el, "type") == 0) {
381 if (attr[0])
382 goto invalid_attr;
383
384 u->current_tag = XML_TAG_TYPE;
385 } else if (u->current_tag == XML_TAG_SERVICE && strcmp(el, "subtype") == 0) {
386 if (attr[0])
387 goto invalid_attr;
388
389 u->current_tag = XML_TAG_SUBTYPE;
390 } else if (u->current_tag == XML_TAG_SERVICE && strcmp(el, "domain-name") == 0) {
391 if (attr[0])
392 goto invalid_attr;
393
394 u->current_tag = XML_TAG_DOMAIN_NAME;
395 } else if (u->current_tag == XML_TAG_SERVICE && strcmp(el, "host-name") == 0) {
396 if (attr[0])
397 goto invalid_attr;
398
399 u->current_tag = XML_TAG_HOST_NAME;
400 } else if (u->current_tag == XML_TAG_SERVICE && strcmp(el, "port") == 0) {
401 if (attr[0])
402 goto invalid_attr;
403
404 u->current_tag = XML_TAG_PORT;
405 } else if (u->current_tag == XML_TAG_SERVICE && strcmp(el, "txt-record") == 0) {
406 if (attr[0])
407 goto invalid_attr;
408
409 u->current_tag = XML_TAG_TXT_RECORD;
410 } else {
411 avahi_log_error("%s: parse failure: didn't expect element <%s>.", u->group->filename, el);
412 u->failed = 1;
413 }
414
415 return;
416
417 invalid_attr:
418 avahi_log_error("%s: parse failure: invalid attribute for element <%s>.", u->group->filename, el);
419 u->failed = 1;
420 return;
421 }
422
xml_end(void * data,AVAHI_GCC_UNUSED const char * el)423 static void XMLCALL xml_end(void *data, AVAHI_GCC_UNUSED const char *el) {
424 struct xml_userdata *u = data;
425 assert(u);
426
427 if (u->failed)
428 return;
429
430 switch (u->current_tag) {
431 case XML_TAG_SERVICE_GROUP:
432
433 if (!u->group->name || !u->group->services) {
434 avahi_log_error("%s: parse failure: service group incomplete.", u->group->filename);
435 u->failed = 1;
436 return;
437 }
438
439 u->current_tag = XML_TAG_INVALID;
440 break;
441
442 case XML_TAG_SERVICE:
443
444 if (!u->service->type) {
445 avahi_log_error("%s: parse failure: service incomplete.", u->group->filename);
446 u->failed = 1;
447 return;
448 }
449
450 u->service = NULL;
451 u->current_tag = XML_TAG_SERVICE_GROUP;
452 break;
453
454 case XML_TAG_NAME:
455 u->current_tag = XML_TAG_SERVICE_GROUP;
456 break;
457
458 case XML_TAG_PORT: {
459 int p;
460 assert(u->service);
461
462 p = u->buf ? atoi(u->buf) : 0;
463
464 if (p < 0 || p > 0xFFFF) {
465 avahi_log_error("%s: parse failure: invalid port specification \"%s\".", u->group->filename, u->buf);
466 u->failed = 1;
467 return;
468 }
469
470 u->service->port = (uint16_t) p;
471
472 u->current_tag = XML_TAG_SERVICE;
473 break;
474 }
475
476 case XML_TAG_TXT_RECORD: {
477 assert(u->service);
478
479 u->service->txt_records = avahi_string_list_add(u->service->txt_records, u->buf ? u->buf : "");
480 u->current_tag = XML_TAG_SERVICE;
481 break;
482 }
483
484 case XML_TAG_SUBTYPE: {
485 assert(u->service);
486
487 u->service->subtypes = avahi_string_list_add(u->service->subtypes, u->buf ? u->buf : "");
488 u->current_tag = XML_TAG_SERVICE;
489 break;
490 }
491
492 case XML_TAG_TYPE:
493 case XML_TAG_DOMAIN_NAME:
494 case XML_TAG_HOST_NAME:
495 u->current_tag = XML_TAG_SERVICE;
496 break;
497
498 case XML_TAG_INVALID:
499 ;
500 }
501
502 avahi_free(u->buf);
503 u->buf = NULL;
504 }
505
append_cdata(char * t,const char * n,int length)506 static char *append_cdata(char *t, const char *n, int length) {
507 char *r, *k;
508
509 if (!length)
510 return t;
511
512
513 k = avahi_strndup(n, length);
514
515 if (t) {
516 r = avahi_strdup_printf("%s%s", t, k);
517 avahi_free(k);
518 avahi_free(t);
519 } else
520 r = k;
521
522 return r;
523 }
524
xml_cdata(void * data,const XML_Char * s,int len)525 static void XMLCALL xml_cdata(void *data, const XML_Char *s, int len) {
526 struct xml_userdata *u = data;
527 assert(u);
528
529 if (u->failed)
530 return;
531
532 switch (u->current_tag) {
533 case XML_TAG_NAME:
534 u->group->name = append_cdata(u->group->name, s, len);
535 break;
536
537 case XML_TAG_TYPE:
538 assert(u->service);
539 u->service->type = append_cdata(u->service->type, s, len);
540 break;
541
542 case XML_TAG_DOMAIN_NAME:
543 assert(u->service);
544 u->service->domain_name = append_cdata(u->service->domain_name, s, len);
545 break;
546
547 case XML_TAG_HOST_NAME:
548 assert(u->service);
549 u->service->host_name = append_cdata(u->service->host_name, s, len);
550 break;
551
552 case XML_TAG_PORT:
553 case XML_TAG_TXT_RECORD:
554 case XML_TAG_SUBTYPE:
555 assert(u->service);
556 u->buf = append_cdata(u->buf, s, len);
557 break;
558
559 case XML_TAG_SERVICE_GROUP:
560 case XML_TAG_SERVICE:
561 case XML_TAG_INVALID:
562 ;
563 }
564 }
565
static_service_group_load(StaticServiceGroup * g)566 static int static_service_group_load(StaticServiceGroup *g) {
567 XML_Parser parser = NULL;
568 int fd = -1;
569 struct xml_userdata u;
570 int r = -1;
571 struct stat st;
572 ssize_t n;
573
574 assert(g);
575
576 u.buf = NULL;
577 u.group = g;
578 u.service = NULL;
579 u.current_tag = XML_TAG_INVALID;
580 u.failed = 0;
581
582 /* Cleanup old data in this service group, if available */
583 remove_static_service_group_from_server(g);
584 while (g->services)
585 static_service_free(g->services);
586
587 avahi_free(g->name);
588 avahi_free(g->chosen_name);
589 g->name = g->chosen_name = NULL;
590 g->replace_wildcards = 0;
591
592 if (!(parser = XML_ParserCreate(NULL))) {
593 avahi_log_error("XML_ParserCreate() failed.");
594 goto finish;
595 }
596
597 if ((fd = open(g->filename, O_RDONLY)) < 0) {
598 avahi_log_error("open(\"%s\", O_RDONLY): %s", g->filename, strerror(errno));
599 goto finish;
600 }
601
602 if (fstat(fd, &st) < 0) {
603 avahi_log_error("fstat(): %s", strerror(errno));
604 goto finish;
605 }
606
607 g->mtime = st.st_mtime;
608
609 XML_SetUserData(parser, &u);
610
611 XML_SetElementHandler(parser, xml_start, xml_end);
612 XML_SetCharacterDataHandler(parser, xml_cdata);
613
614 do {
615 void *buffer;
616
617 #define BUFSIZE (10*1024)
618
619 if (!(buffer = XML_GetBuffer(parser, BUFSIZE))) {
620 avahi_log_error("XML_GetBuffer() failed.");
621 goto finish;
622 }
623
624 if ((n = read(fd, buffer, BUFSIZE)) < 0) {
625 avahi_log_error("read(): %s\n", strerror(errno));
626 goto finish;
627 }
628
629 if (!XML_ParseBuffer(parser, n, n == 0)) {
630 avahi_log_error("XML_ParseBuffer() failed at line %d: %s.\n", (int) XML_GetCurrentLineNumber(parser), XML_ErrorString(XML_GetErrorCode(parser)));
631 goto finish;
632 }
633
634 } while (n != 0);
635
636 if (!u.failed)
637 r = 0;
638
639 finish:
640
641 if (fd >= 0)
642 close(fd);
643
644 if (parser)
645 XML_ParserFree(parser);
646
647 avahi_free(u.buf);
648
649 return r;
650 }
651
load_file(char * n)652 static void load_file(char *n) {
653 StaticServiceGroup *g;
654 assert(n);
655
656 for (g = groups; g; g = g->groups_next)
657 if (strcmp(g->filename, n) == 0)
658 return;
659
660 avahi_log_info("Loading service file %s.", n);
661
662 g = static_service_group_new(n);
663 if (static_service_group_load(g) < 0) {
664 avahi_log_error("Failed to load service group file %s, ignoring.", g->filename);
665 static_service_group_free(g);
666 }
667 }
668
static_service_load(int in_chroot)669 void static_service_load(int in_chroot) {
670 StaticServiceGroup *g, *n;
671 glob_t globbuf;
672 int globret;
673 char **p;
674
675 for (g = groups; g; g = n) {
676 struct stat st;
677
678 n = g->groups_next;
679
680 if (stat(g->filename, &st) < 0) {
681
682 if (errno == ENOENT)
683 avahi_log_info("Service group file %s vanished, removing services.", g->filename);
684 else
685 avahi_log_warn("Failed to stat() file %s, ignoring: %s", g->filename, strerror(errno));
686
687 static_service_group_free(g);
688 } else if (st.st_mtime != g->mtime) {
689 avahi_log_info("Service group file %s changed, reloading.", g->filename);
690
691 if (static_service_group_load(g) < 0) {
692 avahi_log_warn("Failed to load service group file %s, removing service.", g->filename);
693 static_service_group_free(g);
694 }
695 }
696 }
697
698 memset(&globbuf, 0, sizeof(globbuf));
699
700 if ((globret = glob(in_chroot ? "/services/*.service" : AVAHI_SERVICE_DIR "/*.service", GLOB_ERR, NULL, &globbuf)) != 0)
701
702 switch (globret) {
703 #ifdef GLOB_NOSPACE
704 case GLOB_NOSPACE:
705 avahi_log_error("Not enough memory to read service directory "AVAHI_SERVICE_DIR".");
706 break;
707 #endif
708 #ifdef GLOB_NOMATCH
709 case GLOB_NOMATCH:
710 avahi_log_info("No service file found in "AVAHI_SERVICE_DIR".");
711 break;
712 #endif
713 default:
714 avahi_log_error("Failed to read "AVAHI_SERVICE_DIR".");
715 break;
716 }
717
718 else {
719 for (p = globbuf.gl_pathv; *p; p++)
720 load_file(*p);
721
722 globfree(&globbuf);
723 }
724 }
725
static_service_free_all(void)726 void static_service_free_all(void) {
727
728 while (groups)
729 static_service_group_free(groups);
730 }
731
static_service_add_to_server(void)732 void static_service_add_to_server(void) {
733 StaticServiceGroup *g;
734
735 for (g = groups; g; g = g->groups_next)
736 add_static_service_group_to_server(g);
737 }
738
static_service_remove_from_server(void)739 void static_service_remove_from_server(void) {
740 StaticServiceGroup *g;
741
742 for (g = groups; g; g = g->groups_next)
743 remove_static_service_group_from_server(g);
744 }
745