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 : add_tag_for_client
259 * Description : Adds the tag for the client.
262 * 1 : client_address = Address of the client
263 * 2 : tag = The tag to add.
264 * 3 : time_to_live = 0, or the number of seconds
265 * the tag remains activated.
269 *********************************************************************/
270 static void add_tag_for_client(const char *client_address,
271 const char *tag, const time_t time_to_live)
273 struct requested_tags *clients_with_tags;
274 struct client_specific_tag *enabled_tags;
276 validate_requested_tags();
278 if (requested_tags == NULL)
280 /* XXX: Code duplication. */
281 requested_tags = zalloc_or_die(sizeof(struct requested_tags));
282 requested_tags->client = strdup_or_die(client_address);
283 requested_tags->tags = zalloc_or_die(sizeof(struct client_specific_tag));
284 requested_tags->tags->name = strdup_or_die(tag);
285 requested_tags->tags->end_of_life = time_to_live ?
286 (time(NULL) + time_to_live) : 0;
288 validate_requested_tags();
293 clients_with_tags = requested_tags;
294 while (clients_with_tags->next != NULL)
296 if (!strcmp(clients_with_tags->client, client_address))
300 clients_with_tags = clients_with_tags->next;
302 if (strcmp(clients_with_tags->client, client_address))
304 /* Client does not have tags yet, add new structure */
305 clients_with_tags->next = zalloc_or_die(sizeof(struct requested_tags));
306 clients_with_tags->next->prev = clients_with_tags;
307 clients_with_tags = clients_with_tags->next;
308 clients_with_tags->client = strdup_or_die(client_address);
309 clients_with_tags->tags = zalloc_or_die(sizeof(struct client_specific_tag));
310 clients_with_tags->tags->name = strdup_or_die(tag);
311 clients_with_tags->tags->end_of_life = time_to_live ?
312 (time(NULL) + time_to_live) : 0;
314 validate_requested_tags();
320 enabled_tags = clients_with_tags->tags;
321 while (enabled_tags != NULL)
323 if (enabled_tags->next == NULL)
325 enabled_tags->next = zalloc_or_die(sizeof(struct client_specific_tag));
326 enabled_tags->next->name = strdup_or_die(tag);
327 clients_with_tags->tags->end_of_life = time_to_live ?
328 (time(NULL) + time_to_live) : 0;
329 enabled_tags->next->prev = enabled_tags;
332 enabled_tags = enabled_tags->next;
335 validate_requested_tags();
339 /*********************************************************************
341 * Function : remove_tag_for_client
343 * Description : Removes the tag for the client.
346 * 1 : client_address = Address of the client
347 * 2 : tag = The tag to remove.
351 *********************************************************************/
352 static void remove_tag_for_client(const char *client_address, const char *tag)
354 struct requested_tags *clients_with_tags;
355 struct client_specific_tag *enabled_tags;
357 validate_requested_tags();
359 clients_with_tags = requested_tags;
360 while (clients_with_tags != NULL && clients_with_tags->client != NULL)
362 if (!strcmp(clients_with_tags->client, client_address))
366 clients_with_tags = clients_with_tags->next;
369 assert(clients_with_tags != NULL);
370 if (clients_with_tags == NULL)
372 log_error(LOG_LEVEL_ERROR,
373 "Tried to remove tag %s for tag-less client %s",
374 tag, client_address);
376 enabled_tags = clients_with_tags->tags;
377 while (enabled_tags != NULL)
379 if (!strcmp(enabled_tags->name, tag))
381 if (enabled_tags->next != NULL)
383 enabled_tags->next->prev = enabled_tags->prev;
384 if (enabled_tags == clients_with_tags->tags)
386 /* Tag is first in line */
387 clients_with_tags->tags = enabled_tags->next;
390 if (enabled_tags->prev != NULL)
392 /* Tag has preceding tag */
393 enabled_tags->prev->next = enabled_tags->next;
395 if (enabled_tags->prev == NULL && enabled_tags->next == NULL)
397 /* Tag is the only one */
398 if (clients_with_tags->next != NULL)
400 /* Client has following client */
401 clients_with_tags->next->prev = clients_with_tags->prev;
403 if (clients_with_tags->prev != NULL)
405 /* Client has preceding client */
406 clients_with_tags->prev->next = clients_with_tags->next;
408 freez(clients_with_tags->client);
409 if (clients_with_tags == requested_tags)
411 /* Removing last tag */
412 freez(requested_tags);
413 clients_with_tags = requested_tags;
417 freez(clients_with_tags);
420 freez(enabled_tags->name);
425 enabled_tags = enabled_tags->next;
428 validate_requested_tags();
433 /*********************************************************************
435 * Function : client_has_requested_tag
437 * Description : Checks whether or not the given client requested
441 * 1 : client_address = Address of the client
442 * 2 : tag = Tag to check.
444 * Returns : TRUE or FALSE.
446 *********************************************************************/
447 int client_has_requested_tag(const char *client_address, const char *tag)
449 struct client_specific_tag *enabled_tags;
451 enabled_tags = get_tags_for_client(client_address);
453 while (enabled_tags != NULL)
455 if (!strcmp(enabled_tags->name, tag))
459 enabled_tags = enabled_tags->next;
466 /*********************************************************************
468 * Function : enable_client_specific_tag
470 * Description : Enables a client-specific-tag for the client
473 * 1 : csp = Current client state (buffers, headers, etc...)
474 * 2 : tag_name = The name of the tag to enable
475 * 3 : time_to_live = If not 0, the number of seconds the
476 * tag should stay enabled.
478 * Returns : JB_ERR_OK on success, JB_ERR_MEMORY or JB_ERR_PARSE.
480 *********************************************************************/
481 jb_err enable_client_specific_tag(struct client_state *csp,
482 const char *tag_name, const time_t time_to_live)
484 struct client_tag_spec *tag;
486 privoxy_mutex_lock(&client_tags_mutex);
488 tag = get_client_specific_tag(csp->config->client_tags, tag_name);
491 privoxy_mutex_unlock(&client_tags_mutex);
495 if (client_has_requested_tag(csp->client_address, tag_name))
497 log_error(LOG_LEVEL_ERROR,
498 "Tag '%s' already enabled for client '%s'", tag->name, csp->client_address);
502 add_tag_for_client(csp->client_address, tag_name, time_to_live);
503 log_error(LOG_LEVEL_INFO,
504 "Tag '%s' enabled for client '%s'. TTL: %d.",
505 tag->name, csp->client_address, time_to_live);
508 privoxy_mutex_unlock(&client_tags_mutex);
514 /*********************************************************************
516 * Function : disable_client_specific_tag
518 * Description : Disables 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 disable
524 * Returns : JB_ERR_OK on success, JB_ERR_MEMORY or JB_ERR_PARSE.
526 *********************************************************************/
527 jb_err disable_client_specific_tag(struct client_state *csp, const char *tag_name)
529 struct client_tag_spec *tag;
531 privoxy_mutex_lock(&client_tags_mutex);
533 tag = get_client_specific_tag(csp->config->client_tags, tag_name);
536 privoxy_mutex_unlock(&client_tags_mutex);
540 if (client_has_requested_tag(csp->client_address, tag_name))
542 remove_tag_for_client(csp->client_address, tag_name);
543 log_error(LOG_LEVEL_INFO,
544 "Tag '%s' disabled for client '%s'", tag->name, csp->client_address);
548 log_error(LOG_LEVEL_ERROR,
549 "Tag '%s' currently not set for client '%s'",
550 tag->name, csp->client_address);
553 privoxy_mutex_unlock(&client_tags_mutex);
559 /*********************************************************************
561 * Function : client_tag_match
563 * Description : Compare a client tag against a client tag pattern.
566 * 1 : pattern = a TAG pattern
567 * 2 : tag = Client tag to match
569 * Returns : Nonzero if the tag matches the pattern, else 0.
571 *********************************************************************/
572 int client_tag_match(const struct pattern_spec *pattern,
573 const struct list *tags)
575 struct list_entry *tag;
577 if (!(pattern->flags & PATTERN_SPEC_CLIENT_TAG_PATTERN))
580 * It's not a client pattern and thus shouldn't
581 * be matched against client tags.
588 for (tag = tags->first; tag != NULL; tag = tag->next)
590 if (0 == regexec(pattern->pattern.tag_regex, tag->str, 0, NULL, 0))
601 /*********************************************************************
603 * Function : set_client_address
605 * Description : Sets the client address that will be used to enable,
606 * disable, or apply client tags.
609 * 1 : csp = Current client state (buffers, headers, etc...)
610 * 2 : headers = Client headers
614 *********************************************************************/
615 void set_client_address(struct client_state *csp, const struct list *headers)
617 if (csp->config->trust_x_forwarded_for)
619 const char *client_address;
621 client_address = get_header_value(headers, "X-Forwarded-For:");
622 if (client_address != NULL)
624 csp->client_address = strdup_or_die(client_address);
625 log_error(LOG_LEVEL_HEADER,
626 "Got client address %s from X-Forwarded-For header",
627 csp->client_address);
631 if (csp->client_address == NULL)
633 csp->client_address = strdup_or_die(csp->ip_addr_str);
638 #error Compiling client-tags.c without FEATURE_CLIENT_TAGS
639 #endif /* def FEATURE_CLIENT_TAGS */