1 /*********************************************************************
3 * File : $Source: /cvsroot/ijbswa/current/client-tags.c,v $
5 * Purpose : Functions related to client-specific tags.
7 * Copyright : Copyright (C) 2016 Fabian Keil <fk@fabiankeil.de>
9 * This program is free software; you can redistribute it
10 * and/or modify it under the terms of the GNU General
11 * Public License as published by the Free Software
12 * Foundation; either version 2 of the License, or (at
13 * your option) any later version.
15 * This program is distributed in the hope that it will
16 * be useful, but WITHOUT ANY WARRANTY; without even the
17 * implied warranty of MERCHANTABILITY or FITNESS FOR A
18 * PARTICULAR PURPOSE. See the GNU General Public
19 * License for more details.
21 * The GNU General Public License should be included with
22 * this file. If not, you can view it at
23 * http://www.gnu.org/copyleft/gpl.html
24 * or write to the Free Software Foundation, Inc., 59
25 * Temple Place - Suite 330, Boston, MA 02111-1307, USA.
27 **********************************************************************/
31 #ifdef FEATURE_CLIENT_TAGS
34 #include <sys/types.h>
47 struct client_specific_tag
53 struct client_specific_tag *next;
54 struct client_specific_tag *prev;
58 * This struct represents tags that have been requested by clients
62 char *client; /**< The IP address of the client that requested the tag */
64 /**< List of tags the client requested .... */
65 struct client_specific_tag *tags;
67 struct requested_tags *next;
68 struct requested_tags *prev;
71 struct requested_tags *requested_tags;
72 static void remove_tag_for_client(const char *client_address, const char *tag);
74 /*********************************************************************
76 * Function : validate_tag_list
78 * Description : Validates the given tag list
81 * 1 : enabled_tags = The tags to validate
85 *********************************************************************/
86 static void validate_tag_list(struct client_specific_tag *enabled_tags)
88 while (enabled_tags != NULL)
90 if (enabled_tags->name == NULL)
92 assert(enabled_tags->name != NULL);
93 log_error(LOG_LEVEL_FATAL, "validate_tag_list(): Tag without name detected");
95 if (enabled_tags->next != NULL)
97 if (enabled_tags->next->prev != enabled_tags)
99 assert(enabled_tags->next->prev == enabled_tags);
100 log_error(LOG_LEVEL_FATAL, "validate_tag_list(): Invalid backlink detected");
103 enabled_tags = enabled_tags->next;
107 /*********************************************************************
109 * Function : validate_requested_tags
111 * Description : Validates the requested_tags list
117 *********************************************************************/
118 static jb_err validate_requested_tags()
120 struct requested_tags *requested_tag;
122 for (requested_tag = requested_tags; requested_tag != NULL;
123 requested_tag = requested_tag->next)
125 if (requested_tag->client == NULL)
127 assert(requested_tag->client != NULL);
128 log_error(LOG_LEVEL_FATAL, "validate_tag_list(): Client not registered");
130 validate_tag_list(requested_tag->tags);
131 if (requested_tag->next != NULL)
133 if (requested_tag->next->prev != requested_tag)
135 assert(requested_tag->next->prev == requested_tag);
136 log_error(LOG_LEVEL_FATAL, "validate_requested_tags(): Invalid backlink detected");
145 /*********************************************************************
147 * Function : get_client_specific_tag
149 * Description : Returns the data for a client-specific-tag specified
153 * 1 : tag_list = The tag list to check
154 * 2 : name = The tag name to look up
156 * Returns : Pointer to tag structure or NULL on error.
158 *********************************************************************/
159 static struct client_tag_spec *get_client_specific_tag(
160 struct client_tag_spec *tag_list, const char *name)
162 struct client_tag_spec *tag;
164 for (tag = tag_list; tag != NULL; tag = tag->next)
166 if (tag->name != NULL && !strcmp(tag->name, name))
172 log_error(LOG_LEVEL_ERROR, "No such tag: '%s'", name);
179 /*********************************************************************
181 * Function : get_tags_for_client
183 * Description : Returns the list of tags the client opted-in.
186 * 1 : client_address = Address of the client
188 * Returns : Pointer to tag structure or NULL on error.
190 *********************************************************************/
191 static struct client_specific_tag *get_tags_for_client(const char *client_address)
193 struct requested_tags *requested_tag;
195 for (requested_tag = requested_tags; requested_tag != NULL;
196 requested_tag = requested_tag->next)
198 if (!strcmp(requested_tag->client, client_address))
200 return requested_tag->tags;
208 /*********************************************************************
210 * Function : get_tag_list_for_client
212 * Description : Provides a list of tag names the client opted-in.
213 * Other tag attributes are not part of the list.
216 * 1 : tag_list = The list to fill in.
217 * 2 : client_address = Address of the client
219 * Returns : Pointer to tag list.
221 *********************************************************************/
222 void get_tag_list_for_client(struct list *tag_list,
223 const char *client_address)
225 struct client_specific_tag *enabled_tags;
226 const time_t now = time(NULL);
228 privoxy_mutex_lock(&client_tags_mutex);
230 enabled_tags = get_tags_for_client(client_address);
231 while (enabled_tags != NULL)
233 if (enabled_tags->end_of_life && (enabled_tags->end_of_life < now))
235 struct client_specific_tag *next_tag = enabled_tags->next;
236 log_error(LOG_LEVEL_INFO,
237 "Tag '%s' for client %s expired %u seconds ago. Deleting it.",
238 enabled_tags->name, client_address,
239 (now - enabled_tags->end_of_life));
240 remove_tag_for_client(client_address, enabled_tags->name);
241 enabled_tags = next_tag;
246 enlist(tag_list, enabled_tags->name);
248 enabled_tags = enabled_tags->next;
251 privoxy_mutex_unlock(&client_tags_mutex);
255 /*********************************************************************
257 * Function : get_next_tag_timeout_for_client
259 * Description : Figures out when the next temporarily enabled tag
260 * for the client will have timed out.
263 * 1 : client_address = Address of the client
265 * Returns : Lowest timeout in seconds
267 *********************************************************************/
268 time_t get_next_tag_timeout_for_client(const char *client_address)
270 struct client_specific_tag *enabled_tags;
271 time_t next_timeout = 0;
272 const time_t now = time(NULL);
274 privoxy_mutex_lock(&client_tags_mutex);
276 enabled_tags = get_tags_for_client(client_address);
277 while (enabled_tags != NULL)
279 log_error(LOG_LEVEL_CGI, "Evaluating tag '%s' for client %s. End of life %d",
280 enabled_tags->name, client_address, enabled_tags->end_of_life);
281 if (enabled_tags->end_of_life)
283 time_t time_left = enabled_tags->end_of_life - now;
284 /* Add a second to make sure the tag will have expired */
286 log_error(LOG_LEVEL_CGI, "%d > %d?", next_timeout, time_left);
287 if (next_timeout == 0 || next_timeout > time_left)
289 next_timeout = time_left;
292 enabled_tags = enabled_tags->next;
295 privoxy_mutex_unlock(&client_tags_mutex);
297 log_error(LOG_LEVEL_CGI, "Next timeout in %d seconds", next_timeout);
303 /*********************************************************************
305 * Function : add_tag_for_client
307 * Description : Adds the tag for the client.
310 * 1 : client_address = Address of the client
311 * 2 : tag = The tag to add.
312 * 3 : time_to_live = 0, or the number of seconds
313 * the tag remains activated.
317 *********************************************************************/
318 static void add_tag_for_client(const char *client_address,
319 const char *tag, const time_t time_to_live)
321 struct requested_tags *clients_with_tags;
322 struct client_specific_tag *enabled_tags;
324 validate_requested_tags();
326 if (requested_tags == NULL)
328 /* XXX: Code duplication. */
329 requested_tags = zalloc_or_die(sizeof(struct requested_tags));
330 requested_tags->client = strdup_or_die(client_address);
331 requested_tags->tags = zalloc_or_die(sizeof(struct client_specific_tag));
332 requested_tags->tags->name = strdup_or_die(tag);
333 requested_tags->tags->end_of_life = time_to_live ?
334 (time(NULL) + time_to_live) : 0;
336 validate_requested_tags();
341 clients_with_tags = requested_tags;
342 while (clients_with_tags->next != NULL)
344 if (!strcmp(clients_with_tags->client, client_address))
348 clients_with_tags = clients_with_tags->next;
350 if (strcmp(clients_with_tags->client, client_address))
352 /* Client does not have tags yet, add new structure */
353 clients_with_tags->next = zalloc_or_die(sizeof(struct requested_tags));
354 clients_with_tags->next->prev = clients_with_tags;
355 clients_with_tags = clients_with_tags->next;
356 clients_with_tags->client = strdup_or_die(client_address);
357 clients_with_tags->tags = zalloc_or_die(sizeof(struct client_specific_tag));
358 clients_with_tags->tags->name = strdup_or_die(tag);
359 clients_with_tags->tags->end_of_life = time_to_live ?
360 (time(NULL) + time_to_live) : 0;
362 validate_requested_tags();
368 enabled_tags = clients_with_tags->tags;
369 while (enabled_tags != NULL)
371 if (enabled_tags->next == NULL)
373 enabled_tags->next = zalloc_or_die(sizeof(struct client_specific_tag));
374 enabled_tags->next->name = strdup_or_die(tag);
375 clients_with_tags->tags->end_of_life = time_to_live ?
376 (time(NULL) + time_to_live) : 0;
377 enabled_tags->next->prev = enabled_tags;
380 enabled_tags = enabled_tags->next;
383 validate_requested_tags();
387 /*********************************************************************
389 * Function : remove_tag_for_client
391 * Description : Removes the tag for the client.
394 * 1 : client_address = Address of the client
395 * 2 : tag = The tag to remove.
399 *********************************************************************/
400 static void remove_tag_for_client(const char *client_address, const char *tag)
402 struct requested_tags *clients_with_tags;
403 struct client_specific_tag *enabled_tags;
405 validate_requested_tags();
407 clients_with_tags = requested_tags;
408 while (clients_with_tags != NULL && clients_with_tags->client != NULL)
410 if (!strcmp(clients_with_tags->client, client_address))
414 clients_with_tags = clients_with_tags->next;
417 assert(clients_with_tags != NULL);
418 if (clients_with_tags == NULL)
420 log_error(LOG_LEVEL_ERROR,
421 "Tried to remove tag %s for tag-less client %s",
422 tag, client_address);
424 enabled_tags = clients_with_tags->tags;
425 while (enabled_tags != NULL)
427 if (!strcmp(enabled_tags->name, tag))
429 if (enabled_tags->next != NULL)
431 enabled_tags->next->prev = enabled_tags->prev;
432 if (enabled_tags == clients_with_tags->tags)
434 /* Tag is first in line */
435 clients_with_tags->tags = enabled_tags->next;
438 if (enabled_tags->prev != NULL)
440 /* Tag has preceding tag */
441 enabled_tags->prev->next = enabled_tags->next;
443 if (enabled_tags->prev == NULL && enabled_tags->next == NULL)
445 /* Tag is the only one */
446 if (clients_with_tags->next != NULL)
448 /* Client has following client */
449 clients_with_tags->next->prev = clients_with_tags->prev;
451 if (clients_with_tags->prev != NULL)
453 /* Client has preceding client */
454 clients_with_tags->prev->next = clients_with_tags->next;
456 freez(clients_with_tags->client);
457 if (clients_with_tags == requested_tags)
459 /* Removing last tag */
460 freez(requested_tags);
461 clients_with_tags = requested_tags;
465 freez(clients_with_tags);
468 freez(enabled_tags->name);
473 enabled_tags = enabled_tags->next;
476 validate_requested_tags();
481 /*********************************************************************
483 * Function : client_has_requested_tag
485 * Description : Checks whether or not the given client requested
489 * 1 : client_address = Address of the client
490 * 2 : tag = Tag to check.
492 * Returns : TRUE or FALSE.
494 *********************************************************************/
495 int client_has_requested_tag(const char *client_address, const char *tag)
497 struct client_specific_tag *enabled_tags;
499 enabled_tags = get_tags_for_client(client_address);
501 while (enabled_tags != NULL)
503 if (!strcmp(enabled_tags->name, tag))
507 enabled_tags = enabled_tags->next;
514 /*********************************************************************
516 * Function : enable_client_specific_tag
518 * Description : Enables a client-specific-tag for the client
521 * 1 : csp = Current client state (buffers, headers, etc...)
522 * 2 : tag_name = The name of the tag to enable
523 * 3 : time_to_live = If not 0, the number of seconds the
524 * tag should stay enabled.
526 * Returns : JB_ERR_OK on success, JB_ERR_MEMORY or JB_ERR_PARSE.
528 *********************************************************************/
529 jb_err enable_client_specific_tag(struct client_state *csp,
530 const char *tag_name, const time_t time_to_live)
532 struct client_tag_spec *tag;
534 privoxy_mutex_lock(&client_tags_mutex);
536 tag = get_client_specific_tag(csp->config->client_tags, tag_name);
539 privoxy_mutex_unlock(&client_tags_mutex);
543 if (client_has_requested_tag(csp->client_address, tag_name))
545 log_error(LOG_LEVEL_ERROR,
546 "Tag '%s' already enabled for client '%s'", tag->name, csp->client_address);
550 add_tag_for_client(csp->client_address, tag_name, time_to_live);
551 log_error(LOG_LEVEL_INFO,
552 "Tag '%s' enabled for client '%s'. TTL: %d.",
553 tag->name, csp->client_address, time_to_live);
556 privoxy_mutex_unlock(&client_tags_mutex);
562 /*********************************************************************
564 * Function : disable_client_specific_tag
566 * Description : Disables a client-specific-tag for the client
569 * 1 : csp = Current client state (buffers, headers, etc...)
570 * 2 : tag_name = The name of the tag to disable
572 * Returns : JB_ERR_OK on success, JB_ERR_MEMORY or JB_ERR_PARSE.
574 *********************************************************************/
575 jb_err disable_client_specific_tag(struct client_state *csp, const char *tag_name)
577 struct client_tag_spec *tag;
579 privoxy_mutex_lock(&client_tags_mutex);
581 tag = get_client_specific_tag(csp->config->client_tags, tag_name);
584 privoxy_mutex_unlock(&client_tags_mutex);
588 if (client_has_requested_tag(csp->client_address, tag_name))
590 remove_tag_for_client(csp->client_address, tag_name);
591 log_error(LOG_LEVEL_INFO,
592 "Tag '%s' disabled for client '%s'", tag->name, csp->client_address);
596 log_error(LOG_LEVEL_ERROR,
597 "Tag '%s' currently not set for client '%s'",
598 tag->name, csp->client_address);
601 privoxy_mutex_unlock(&client_tags_mutex);
607 /*********************************************************************
609 * Function : client_tag_match
611 * Description : Compare a client tag against a client tag pattern.
614 * 1 : pattern = a TAG pattern
615 * 2 : tag = Client tag to match
617 * Returns : Nonzero if the tag matches the pattern, else 0.
619 *********************************************************************/
620 int client_tag_match(const struct pattern_spec *pattern,
621 const struct list *tags)
623 struct list_entry *tag;
625 if (!(pattern->flags & PATTERN_SPEC_CLIENT_TAG_PATTERN))
628 * It's not a client pattern and thus shouldn't
629 * be matched against client tags.
636 for (tag = tags->first; tag != NULL; tag = tag->next)
638 if (0 == regexec(pattern->pattern.tag_regex, tag->str, 0, NULL, 0))
649 /*********************************************************************
651 * Function : set_client_address
653 * Description : Sets the client address that will be used to enable,
654 * disable, or apply client tags.
657 * 1 : csp = Current client state (buffers, headers, etc...)
658 * 2 : headers = Client headers
662 *********************************************************************/
663 void set_client_address(struct client_state *csp, const struct list *headers)
665 if (csp->config->trust_x_forwarded_for)
667 const char *client_address;
669 client_address = get_header_value(headers, "X-Forwarded-For:");
670 if (client_address != NULL)
672 csp->client_address = strdup_or_die(client_address);
673 log_error(LOG_LEVEL_HEADER,
674 "Got client address %s from X-Forwarded-For header",
675 csp->client_address);
679 if (csp->client_address == NULL)
681 csp->client_address = strdup_or_die(csp->ip_addr_str);
686 #error Compiling client-tags.c without FEATURE_CLIENT_TAGS
687 #endif /* def FEATURE_CLIENT_TAGS */