1 const char filters_rcs[] = "$Id: filters.c,v 1.108 2008/05/21 15:35:08 fabiankeil Exp $";
2 /*********************************************************************
4 * File : $Source: /cvsroot/ijbswa/current/filters.c,v $
6 * Purpose : Declares functions to parse/crunch headers and pages.
7 * Functions declared include:
8 * `acl_addr', `add_stats', `block_acl', `block_imageurl',
9 * `block_url', `url_actions', `domain_split',
10 * `filter_popups', `forward_url', 'redirect_url',
11 * `ij_untrusted_url', `intercept_url', `pcrs_filter_respose',
12 * `ijb_send_banner', `trust_url', `gif_deanimate_response',
13 * `execute_single_pcrs_command', `rewrite_url',
16 * Copyright : Written by and Copyright (C) 2001, 2004-2008 the SourceForge
17 * Privoxy team. http://www.privoxy.org/
19 * Based on the Internet Junkbuster originally written
20 * by and Copyright (C) 1997 Anonymous Coders and
21 * Junkbusters Corporation. http://www.junkbusters.com
23 * This program is free software; you can redistribute it
24 * and/or modify it under the terms of the GNU General
25 * Public License as published by the Free Software
26 * Foundation; either version 2 of the License, or (at
27 * your option) any later version.
29 * This program is distributed in the hope that it will
30 * be useful, but WITHOUT ANY WARRANTY; without even the
31 * implied warranty of MERCHANTABILITY or FITNESS FOR A
32 * PARTICULAR PURPOSE. See the GNU General Public
33 * License for more details.
35 * The GNU General Public License should be included with
36 * this file. If not, you can view it at
37 * http://www.gnu.org/copyleft/gpl.html
38 * or write to the Free Software Foundation, Inc., 59
39 * Temple Place - Suite 330, Boston, MA 02111-1307, USA.
43 * Revision 1.108 2008/05/21 15:35:08 fabiankeil
44 * - Mark csp as immutable for block_acl().
45 * - Remove an obsolete complaint about filter_popups().
47 * Revision 1.107 2008/05/04 17:52:56 fabiankeil
48 * Adjust parse_http_url() call to new prototype.
50 * Revision 1.106 2008/05/03 16:40:44 fabiankeil
51 * Change content_filters_enabled()'s parameter from
52 * csp->action to action so it can be also used in the
53 * CGI code. Don't bother checking if there are filters
54 * loaded, as that's somewhat besides the point.
56 * Revision 1.105 2008/03/28 15:13:39 fabiankeil
57 * Remove inspect-jpegs action.
59 * Revision 1.104 2008/03/27 18:27:24 fabiankeil
60 * Remove kill-popups action.
62 * Revision 1.103 2008/03/06 16:33:45 fabiankeil
63 * If limit-connect isn't used, don't limit CONNECT requests to port 443.
65 * Revision 1.102 2008/03/01 14:00:44 fabiankeil
66 * Let the block action take the reason for the block
67 * as argument and show it on the "blocked" page.
69 * Revision 1.101 2008/02/23 16:57:12 fabiankeil
70 * Rename url_actions() to get_url_actions() and let it
71 * use the standard parameter ordering.
73 * Revision 1.100 2008/02/23 16:33:43 fabiankeil
74 * Let forward_url() use the standard parameter ordering
75 * and mark its second parameter immutable.
77 * Revision 1.99 2008/02/03 13:57:58 fabiankeil
78 * Add SOCKS5 support for forward-override{}.
80 * Revision 1.98 2008/01/04 17:43:45 fabiankeil
81 * Improve the warning messages that get logged if the action files
82 * "enable" filters but no filters of that type have been loaded.
84 * Revision 1.97 2007/11/30 15:37:03 fabiankeil
85 * Use freez instead of free.
87 * Revision 1.96 2007/10/19 16:53:28 fabiankeil
88 * Add helper function to check if any content filters are enabled.
90 * Revision 1.95 2007/10/17 19:31:20 fabiankeil
91 * Omitting the zero chunk that ends the chunk transfer encoding seems
92 * to be the new black. Log the problem and continue filtering anyway.
94 * Revision 1.94 2007/09/29 13:20:20 fabiankeil
95 * Remove two redundant and one useless log messages.
97 * Revision 1.93 2007/09/29 10:21:16 fabiankeil
98 * - Move get_filter_function() from jcc.c to filters.c
99 * so the filter functions can be static.
100 * - Don't bother filtering body-less responses.
102 * Revision 1.92 2007/09/28 16:38:55 fabiankeil
103 * - Execute content filters through execute_content_filter().
104 * - Add prepare_for_filtering() so filter functions don't have to
105 * care about de-chunking and decompression. As a side effect this enables
106 * decompression for gif_deanimate_response() and jpeg_inspect_response().
107 * - Change remove_chunked_transfer_coding()'s return type to jb_err.
108 * Some clowns feel like chunking empty responses in which case
109 * (size == 0) is valid but previously would be interpreted as error.
111 * Revision 1.91 2007/09/02 15:31:20 fabiankeil
112 * Move match_portlist() from filter.c to urlmatch.c.
113 * It's used for url matching, not for filtering.
115 * Revision 1.90 2007/09/02 12:44:17 fabiankeil
116 * Remove newline at the end of a log_error() message.
118 * Revision 1.89 2007/08/05 13:42:23 fabiankeil
119 * #1763173 from Stefan Huehner: declare some more functions static.
121 * Revision 1.88 2007/06/01 16:41:11 fabiankeil
122 * Add forward-override{} to change the forwarding settings through
123 * action sections. This is mainly interesting to forward different
124 * clients differently (for example based on User-Agent or request
127 * Revision 1.87 2007/04/30 15:53:10 fabiankeil
128 * Make sure filters with dynamic jobs actually use them.
130 * Revision 1.86 2007/04/30 15:03:28 fabiankeil
131 * - Introduce dynamic pcrs jobs that can resolve variables.
132 * - Don't run redirect functions more than once,
133 * unless they are activated more than once.
135 * Revision 1.85 2007/03/21 12:24:47 fabiankeil
136 * - Log the content size after decompression in decompress_iob()
137 * instead of pcrs_filter_response().
139 * Revision 1.84 2007/03/20 15:16:34 fabiankeil
140 * Use dedicated header filter actions instead of abusing "filter".
141 * Replace "filter-client-headers" and "filter-client-headers"
142 * with "server-header-filter" and "client-header-filter".
144 * Revision 1.83 2007/03/17 15:20:05 fabiankeil
145 * New config option: enforce-blocks.
147 * Revision 1.82 2007/03/13 11:28:43 fabiankeil
148 * - Fix port handling in acl_addr() and use a temporary acl spec
149 * copy so error messages don't contain a truncated version.
150 * - Log size of iob before and after decompression.
152 * Revision 1.81 2007/03/05 14:40:53 fabiankeil
153 * - Cosmetical changes for LOG_LEVEL_RE_FILTER messages.
154 * - Hide the "Go there anyway" link for blocked CONNECT
155 * requests where going there anyway doesn't work anyway.
157 * Revision 1.80 2007/02/07 10:55:20 fabiankeil
158 * - Save the reason for generating http_responses.
159 * - Block (+block) with status code 403 instead of 404.
160 * - Use a different kludge to remember a failed decompression.
162 * Revision 1.79 2007/01/31 16:21:38 fabiankeil
163 * Search for Max-Forwards headers case-insensitive,
164 * don't generate the "501 unsupported" message for invalid
165 * Max-Forwards values and don't increase negative ones.
167 * Revision 1.78 2007/01/28 13:41:18 fabiankeil
168 * - Add HEAD support to finish_http_response.
169 * - Add error favicon to internal HTML error messages.
171 * Revision 1.77 2007/01/12 15:36:44 fabiankeil
172 * Mark *csp as immutable for is_untrusted_url()
173 * and is_imageurl(). Closes FR 1237736.
175 * Revision 1.76 2007/01/01 19:36:37 fabiankeil
176 * Integrate a modified version of Wil Mahan's
177 * zlib patch (PR #895531).
179 * Revision 1.75 2006/12/29 18:30:46 fabiankeil
180 * Fixed gcc43 conversion warnings,
181 * changed sprintf calls to snprintf.
183 * Revision 1.74 2006/12/24 17:37:38 fabiankeil
184 * Adjust comment in pcrs_filter_response()
185 * to recent pcrs changes. Hohoho.
187 * Revision 1.73 2006/12/23 16:01:02 fabiankeil
188 * Don't crash if pcre returns an error code
189 * that pcrs didn't expect. Fixes BR 1621173.
191 * Revision 1.72 2006/12/22 18:52:53 fabiankeil
192 * Modified is_untrusted_url to complain in case of
193 * write errors and to give a reason when adding new
194 * entries to the trustfile. Closes FR 1097611.
196 * Revision 1.71 2006/12/22 14:24:52 fabiankeil
197 * Skip empty filter files in pcrs_filter_response,
198 * but don't ignore the ones that come afterwards.
199 * Fixes parts of BR 1619208.
201 * Revision 1.70 2006/12/09 13:33:15 fabiankeil
202 * Added some sanity checks for get_last_url().
203 * Fixed possible segfault caused by my last commit.
205 * Revision 1.69 2006/12/08 12:39:13 fabiankeil
206 * Let get_last_url() catch https URLs as well.
208 * Revision 1.68 2006/12/05 14:45:48 fabiankeil
209 * Make sure get_last_url() behaves like advertised
210 * and fast-redirects{} can be combined with redirect{}.
212 * Revision 1.67 2006/11/28 15:19:43 fabiankeil
213 * Implemented +redirect{s@foo@bar@} to generate
214 * a redirect based on a rewritten version of the
217 * Revision 1.66 2006/09/23 13:26:38 roro
218 * Replace TABs by spaces in source code.
220 * Revision 1.65 2006/09/21 12:54:43 fabiankeil
221 * Fix +redirect{}. Didn't work with -fast-redirects.
223 * Revision 1.64 2006/08/31 10:55:49 fabiankeil
224 * Block requests for untrusted URLs with status
225 * code 403 instead of 200.
227 * Revision 1.63 2006/08/31 10:11:28 fabiankeil
228 * Don't free p which is still in use and will be later
229 * freed by free_map(). Don't claim the referrer is unknown
230 * when the client didn't set one.
232 * Revision 1.62 2006/08/14 00:27:47 david__schmidt
233 * Feature request 595948: Re-Filter logging in single line
235 * Revision 1.61 2006/08/03 02:46:41 david__schmidt
236 * Incorporate Fabian Keil's patch work:
\rhttp://www.fabiankeil.de/sourcecode/privoxy/
238 * Revision 1.60 2006/07/18 14:48:46 david__schmidt
239 * Reorganizing the repository: swapping out what was HEAD (the old 3.1 branch)
240 * with what was really the latest development (the v_3_0_branch branch)
242 * Revision 1.58.2.9 2006/01/29 23:10:56 david__schmidt
243 * Multiple filter file support
245 * Revision 1.58.2.8 2005/05/07 21:50:55 david__schmidt
246 * A few memory leaks plugged (mostly on error paths)
248 * Revision 1.58.2.7 2004/10/03 12:53:32 david__schmidt
249 * Add the ability to check jpeg images for invalid
250 * lengths of comment blocks. Defensive strategy
251 * against the exploit:
252 * Microsoft Security Bulletin MS04-028
253 * Buffer Overrun in JPEG Processing (GDI+) Could
254 * Allow Code Execution (833987)
255 * Enabled with +inspect-jpegs in actions files.
257 * Revision 1.58.2.6 2003/12/06 22:18:27 gliptak
258 * Correcting compile problem with FEATURE_IMAGE_BLOCKING
260 * Revision 1.58.2.5 2003/11/11 13:10:31 oes
261 * Fixed bug #839859: "See why" link URL now gets url-encoded.
263 * Revision 1.58.2.4 2003/02/28 12:52:45 oes
266 * Revision 1.58.2.3 2002/09/25 14:51:51 oes
267 * Added basic support for OPTIONS and TRACE HTTP methods:
268 * New function direct_response which handles OPTIONS and
269 * TRACE requests whose Max-Forwards header field is zero.
271 * Revision 1.58.2.2 2002/08/01 17:18:28 oes
272 * Fixed BR 537651 / SR 579724 (MSIE image detect improper for IE/Mac)
274 * Revision 1.58.2.1 2002/07/26 15:18:53 oes
275 * - Bugfix: Executing a filters without jobs no longer results in
276 * turing off *all* filters.
277 * - Security fix: Malicious web servers can't cause a seg fault
278 * through bogus chunk sizes anymore
280 * Revision 1.58 2002/04/24 02:11:17 oes
281 * Jon's multiple AF patch: url_actions now evaluates rules
284 * Revision 1.57 2002/04/08 20:38:34 swa
287 * Revision 1.56 2002/04/05 15:51:24 oes
288 * - bugfix: error-pages now get correct request protocol
289 * - fix for invalid HTML in trust info
291 * Revision 1.55 2002/04/02 16:13:51 oes
292 * Fix: No "Go there anyway" for SSL
294 * Revision 1.54 2002/04/02 14:55:56 oes
295 * Bugfix: is_untrusted_url() now depends on FEATURE_TRUST, not FEATURE_COOKIE_JAR
297 * Revision 1.53 2002/03/26 22:29:54 swa
298 * we have a new homepage!
300 * Revision 1.52 2002/03/24 16:35:57 jongfoster
303 * Revision 1.51 2002/03/24 15:23:33 jongfoster
306 * Revision 1.50 2002/03/24 13:25:43 swa
307 * name change related issues
309 * Revision 1.49 2002/03/16 20:29:14 oes
312 * Revision 1.48 2002/03/13 20:25:34 oes
313 * Better logging for content filters
315 * Revision 1.47 2002/03/13 00:30:52 jongfoster
317 * Added option of always sending redirect for imageblock,
318 * currently disabled with #if 0.
320 * Revision 1.46 2002/03/12 01:42:49 oes
321 * Introduced modular filters
323 * Revision 1.45 2002/03/08 16:47:50 oes
324 * Added choice beween GIF and PNG built-in images
326 * Revision 1.44 2002/03/07 03:49:31 oes
327 * - Fixed compiler warnings etc
328 * - Changed built-in images from GIF to PNG
329 * (with regard to Unisys patent issue)
330 * - Added a 4x4 pattern PNG which is less intrusive
331 * than the logo but also clearly marks the deleted banners
333 * Revision 1.43 2002/01/22 23:51:59 jongfoster
334 * Replacing strsav() with the safer string_append().
336 * Adding missing html_encode() to error message generators. Where encoded
337 * and unencoded versions of a string were provided, removing the unencoded
340 * Revision 1.42 2002/01/17 21:00:32 jongfoster
341 * Moving all our URL and URL pattern parsing code to urlmatch.c.
343 * Using a single, simple url_match(pattern,url) function - rather than
344 * the 3-line match routine which was repeated all over the place.
346 * Renaming free_url to free_url_spec, since it frees a struct url_spec.
348 * Using parse_http_url() to parse URLs without faking a HTTP
349 * request line for parse_http_request().
351 * Revision 1.41 2001/11/13 00:14:07 jongfoster
352 * Fixing stupid bug now I've figured out what || means.
353 * (It always returns 0 or 1, not one of it's paramaters.)
355 * Revision 1.40 2001/10/26 17:37:55 oes
356 * - Re-enabled Netscape 200/404 bug workaround in block_url():
357 * - Removed OS/2 special case
358 * - Made block_url() independant from sed() having been run
359 * - Made trust_url independant from sed() having been run
360 * - Made is_imageurl independant from sed() having been run.
361 * It now checks User-Agent: and Accept: by itself.
364 * Revision 1.39 2001/10/25 03:40:48 david__schmidt
365 * Change in porting tactics: OS/2's EMX porting layer doesn't allow multiple
366 * threads to call select() simultaneously. So, it's time to do a real, live,
367 * native OS/2 port. See defines for __EMX__ (the porting layer) vs. __OS2__
368 * (native). Both versions will work, but using __OS2__ offers multi-threading.
370 * Revision 1.38 2001/10/23 21:32:33 jongfoster
371 * Adding error-checking to selected functions
373 * Revision 1.37 2001/10/22 15:33:56 david__schmidt
374 * Special-cased OS/2 out of the Netscape-abort-on-404-in-js problem in
375 * filters.c. Added a FIXME in front of the offending code. I'll gladly
376 * put in a better/more robust fix for all parties if one is presented...
377 * It seems that just returning 200 instead of 404 would pretty much fix
378 * it for everyone, but I don't know all the history of the problem.
380 * Revision 1.36 2001/10/10 16:44:16 oes
381 * Added match_portlist function
383 * Revision 1.35 2001/10/07 15:41:23 oes
384 * Replaced 6 boolean members of csp with one bitmap (csp->flags)
386 * New function remove_chunked_transfer_coding that strips chunked
387 * transfer coding to plain and is called by pcrs_filter_response
388 * and gif_deanimate_response if neccessary
390 * Improved handling of zero-change re_filter runs
392 * pcrs_filter_response and gif_deanimate_response now remove
393 * chunked transfer codeing before processing the body.
395 * Revision 1.34 2001/09/20 15:49:36 steudten
397 * Fix BUG: Change int size to size_t size in pcrs_filter_response().
398 * See cgi.c fill_template().
400 * Revision 1.33 2001/09/16 17:05:14 jongfoster
401 * Removing unused #include showarg.h
403 * Revision 1.32 2001/09/16 13:21:27 jongfoster
404 * Changes to use new list functions.
406 * Revision 1.31 2001/09/16 11:38:02 jongfoster
407 * Splitting fill_template() into 2 functions:
408 * template_load() loads the file
409 * template_fill() performs the PCRS regexps.
410 * This is because the CGI edit interface has a "table row"
411 * template which is used many times in the page - this
412 * change means it's only loaded from disk once.
414 * Revision 1.30 2001/09/16 11:00:10 jongfoster
415 * New function alloc_http_response, for symmetry with free_http_response
417 * Revision 1.29 2001/09/13 23:32:40 jongfoster
418 * Moving image data to cgi.c rather than cgi.h
419 * Fixing a GPF under Win32 (and any other OS that protects global
420 * constants from being written to).
422 * Revision 1.28 2001/09/10 10:18:51 oes
423 * Silenced compiler warnings
425 * Revision 1.27 2001/08/05 16:06:20 jongfoster
426 * Modifiying "struct map" so that there are now separate header and
427 * "map_entry" structures. This means that functions which modify a
428 * map no longer need to return a pointer to the modified map.
429 * Also, it no longer reverses the order of the entries (which may be
430 * important with some advanced template substitutions).
432 * Revision 1.26 2001/07/30 22:08:36 jongfoster
433 * Tidying up #defines:
434 * - All feature #defines are now of the form FEATURE_xxx
435 * - Permanently turned off WIN_GUI_EDIT
436 * - Permanently turned on WEBDAV and SPLIT_PROXY_ARGS
438 * Revision 1.25 2001/07/26 10:09:46 oes
439 * Made browser detection a little less naive
441 * Revision 1.24 2001/07/25 17:22:51 oes
442 * Added workaround for Netscape bug that prevents display of page when loading a component fails.
444 * Revision 1.23 2001/07/23 13:40:12 oes
445 * Fixed bug that caused document body to be dropped when pcrs joblist was empty.
447 * Revision 1.22 2001/07/18 12:29:34 oes
448 * - Made gif_deanimate_response respect
449 * csp->action->string[ACTION_STRING_DEANIMATE]
450 * - Logging cosmetics
452 * Revision 1.21 2001/07/13 13:59:53 oes
453 * - Introduced gif_deanimate_response which shares the
454 * generic content modification interface of pcrs_filter_response
455 * and acts as a wrapper to deanimate.c:gif_deanimate()
456 * - Renamed re_process_buffer to pcrs_filter_response
457 * - pcrs_filter_response now returns NULL on failiure
458 * - Removed all #ifdef PCRS
460 * Revision 1.20 2001/07/01 17:01:04 oes
461 * Added comments and missing return statement in is_untrusted_url()
463 * Revision 1.19 2001/06/29 21:45:41 oes
464 * Indentation, CRLF->LF, Tab-> Space
466 * Revision 1.18 2001/06/29 13:27:38 oes
467 * - Cleaned up, renamed and reorderd functions
468 * and improved comments
471 * - Ported to CGI platform. Now delivers
472 * http_response or NULL
473 * - Unified HTML and GIF generation (moved image detection
474 * and GIF generation here from jcc.c:chat())
475 * - Fixed HTTP status to:
476 * - 403 (Forbidden) for the "blocked" HTML message
477 * - 200 (OK) for GIF answers
478 * - 302 (Redirect) for redirect to GIF
481 * - Ported to CGI platform. Now delivers
482 * http_response or NULL
483 * - Separated detection of untrusted URL into
484 * (bool)is_untrusted_url
485 * - Added enforcement of untrusted requests
487 * - Moved redirect_url() from cgi.c to here
488 * and ported it to the CGI platform
490 * - Removed logentry from cancelled commit
492 * Revision 1.17 2001/06/09 10:55:28 jongfoster
493 * Changing BUFSIZ ==> BUFFER_SIZE
495 * Revision 1.16 2001/06/07 23:10:26 jongfoster
496 * Allowing unanchored domain patterns to back off and retry
497 * if they partially match. Optimized right-anchored patterns.
498 * Moving ACL and forward files into config file.
499 * Replacing struct gateway with struct forward_spec
501 * Revision 1.15 2001/06/03 19:12:00 oes
502 * extracted-CGI relevant stuff
504 * Revision 1.14 2001/06/01 10:30:55 oes
505 * Added optional left-anchoring to domaincmp
507 * Revision 1.13 2001/05/31 21:21:30 jongfoster
508 * Permissionsfile / actions file changes:
509 * - Changed "permission" to "action" throughout
510 * - changes to file format to allow string parameters
511 * - Moved helper functions to actions.c
513 * Revision 1.12 2001/05/31 17:35:20 oes
515 * - Enhanced domain part globbing with infix and prefix asterisk
516 * matching and optional unanchored operation
518 * Revision 1.11 2001/05/29 11:53:23 oes
519 * "See why" link added to "blocked" page
521 * Revision 1.10 2001/05/29 09:50:24 jongfoster
522 * Unified blocklist/imagelist/permissionslist.
523 * File format is still under discussion, but the internal changes
526 * Also modified interceptor behaviour:
527 * - We now intercept all URLs beginning with one of the following
528 * prefixes (and *only* these prefixes):
530 * * http://ijbswa.sf.net/config/
531 * * http://ijbswa.sourceforge.net/config/
532 * - New interceptors "home page" - go to http://i.j.b/ to see it.
533 * - Internal changes so that intercepted and fast redirect pages
534 * are not replaced with an image.
535 * - Interceptors now have the option to send a binary page direct
536 * to the client. (i.e. ijb-send-banner uses this)
537 * - Implemented show-url-info interceptor. (Which is why I needed
538 * the above interceptors changes - a typical URL is
539 * "http://i.j.b/show-url-info?url=www.somesite.com/banner.gif".
540 * The previous mechanism would not have intercepted that, and
541 * if it had been intercepted then it then it would have replaced
544 * Revision 1.9 2001/05/27 22:17:04 oes
546 * - re_process_buffer no longer writes the modified buffer
547 * to the client, which was very ugly. It now returns the
548 * buffer, which it is then written by chat.
550 * - content_length now adjusts the Content-Length: header
551 * for modified documents rather than crunch()ing it.
552 * (Length info in csp->content_length, which is 0 for
553 * unmodified documents)
555 * - For this to work, sed() is called twice when filtering.
557 * Revision 1.8 2001/05/26 17:13:28 jongfoster
558 * Filled in a function comment.
560 * Revision 1.7 2001/05/26 15:26:15 jongfoster
561 * ACL feature now provides more security by immediately dropping
562 * connections from untrusted hosts.
564 * Revision 1.6 2001/05/26 00:28:36 jongfoster
565 * Automatic reloading of config file.
566 * Removed obsolete SIGHUP support (Unix) and Reload menu option (Win32).
567 * Most of the global variables have been moved to a new
568 * struct configuration_spec, accessed through csp->config->globalname
569 * Most of the globals remaining are used by the Win32 GUI.
571 * Revision 1.5 2001/05/25 22:34:30 jongfoster
574 * Revision 1.4 2001/05/22 18:46:04 oes
576 * - Enabled filtering banners by size rather than URL
577 * by adding patterns that replace all standard banner
578 * sizes with the "Junkbuster" gif to the re_filterfile
580 * - Enabled filtering WebBugs by providing a pattern
581 * which kills all 1x1 images
583 * - Added support for PCRE_UNGREEDY behaviour to pcrs,
584 * which is selected by the (nonstandard and therefore
585 * capital) letter 'U' in the option string.
586 * It causes the quantifiers to be ungreedy by default.
587 * Appending a ? turns back to greedy (!).
589 * - Added a new interceptor ijb-send-banner, which
590 * sends back the "Junkbuster" gif. Without imagelist or
591 * MSIE detection support, or if tinygif = 1, or the
592 * URL isn't recognized as an imageurl, a lame HTML
593 * explanation is sent instead.
595 * - Added new feature, which permits blocking remote
596 * script redirects and firing back a local redirect
598 * The feature is conditionally compiled, i.e. it
599 * can be disabled with --disable-fast-redirects,
600 * plus it must be activated by a "fast-redirects"
601 * line in the config file, has its own log level
602 * and of course wants to be displayed by show-proxy-args
603 * Note: Boy, all the #ifdefs in 1001 locations and
604 * all the fumbling with configure.in and acconfig.h
605 * were *way* more work than the feature itself :-(
607 * - Because a generic redirect template was needed for
608 * this, tinygif = 3 now uses the same.
610 * - Moved GIFs, and other static HTTP response templates
615 * - Removed some >400 CRs again (Jon, you really worked
618 * Revision 1.3 2001/05/20 16:44:47 jongfoster
619 * Removing last hardcoded Junkbusters.com URLs.
621 * Revision 1.2 2001/05/20 01:21:20 jongfoster
622 * Version 2.9.4 checkin.
623 * - Merged popupfile and cookiefile, and added control over PCRS
624 * filtering, in new "permissionsfile".
625 * - Implemented LOG_LEVEL_FATAL, so that if there is a configuration
626 * file error you now get a message box (in the Win32 GUI) rather
627 * than the program exiting with no explanation.
628 * - Made killpopup use the PCRS MIME-type checking and HTTP-header
630 * - Removed tabs from "config"
631 * - Moved duplicated url parsing code in "loaders.c" to a new funcition.
632 * - Bumped up version number.
634 * Revision 1.1.1.1 2001/05/15 13:58:52 oes
635 * Initial import of version 2.9.3 source tree
638 *********************************************************************/
644 #include <sys/types.h>
653 #endif /* ndef __OS2__ */
654 #include <netinet/in.h>
656 #include <winsock2.h>
657 #endif /* ndef _WIN32 */
661 #endif /* def __OS2__ */
669 #include "jbsockets.h"
670 #include "miscutil.h"
674 #include "deanimate.h"
675 #include "urlmatch.h"
682 const char filters_h_rcs[] = FILTERS_H_VERSION;
684 /* Fix a problem with Solaris. There should be no effect on other
686 * Solaris's isspace() is a macro which uses it's argument directly
687 * as an array index. Therefore we need to make sure that high-bit
688 * characters generate +ve values, and ideally we also want to make
689 * the argument match the declared parameter type of "int".
691 #define ijb_isdigit(__X) isdigit((int)(unsigned char)(__X))
693 static jb_err remove_chunked_transfer_coding(char *buffer, size_t *size);
694 static jb_err prepare_for_filtering(struct client_state *csp);
697 /*********************************************************************
699 * Function : block_acl
701 * Description : Block this request?
702 * Decide yes or no based on ACL file.
705 * 1 : dst = The proxy or gateway address this is going to.
706 * Or NULL to check all possible targets.
707 * 2 : csp = Current client state (buffers, headers, etc...)
708 * Also includes the client IP address.
710 * Returns : 0 = FALSE (don't block) and 1 = TRUE (do block)
712 *********************************************************************/
713 int block_acl(const struct access_control_addr *dst, const struct client_state *csp)
715 struct access_control_list *acl = csp->config->acl;
717 /* if not using an access control list, then permit the connection */
723 /* search the list */
726 if ((csp->ip_addr_long & acl->src->mask) == acl->src->addr)
730 /* Just want to check if they have any access */
731 if (acl->action == ACL_PERMIT)
736 else if ( ((dst->addr & acl->dst->mask) == acl->dst->addr)
737 && ((dst->port == acl->dst->port) || (acl->dst->port == 0)))
739 if (acl->action == ACL_PERMIT)
757 /*********************************************************************
759 * Function : acl_addr
761 * Description : Called from `load_config' to parse an ACL address.
764 * 1 : aspec = String specifying ACL address.
765 * 2 : aca = struct access_control_addr to fill in.
767 * Returns : 0 => Ok, everything else is an error.
769 *********************************************************************/
770 int acl_addr(const char *aspec, struct access_control_addr *aca)
775 char *acl_spec = NULL;
781 * Use a temporary acl spec copy so we can log
782 * the unmodified original in case of parse errors.
784 acl_spec = strdup(aspec);
785 if (acl_spec == NULL)
787 /* XXX: This will be logged as parse error. */
791 if ((p = strchr(acl_spec, '/')) != NULL)
794 if (ijb_isdigit(*p) == 0)
799 masklength = atoi(p);
802 if ((masklength < 0) || (masklength > 32))
808 if ((p = strchr(acl_spec, ':')) != NULL)
813 port = strtol(p, &endptr, 10);
815 if (port <= 0 || port > 65535 || *endptr != '\0')
822 aca->port = (unsigned long)port;
824 aca->addr = ntohl(resolve_hostname_to_ip(acl_spec));
827 if (aca->addr == INADDR_NONE)
829 /* XXX: This will be logged as parse error. */
833 /* build the netmask */
835 for (i=1; i <= masklength ; i++)
837 aca->mask |= (1 << (32 - i));
840 /* now mask off the host portion of the ip address
841 * (i.e. save on the network portion of the address).
843 aca->addr = aca->addr & aca->mask;
848 #endif /* def FEATURE_ACL */
851 /*********************************************************************
853 * Function : connect_port_is_forbidden
855 * Description : Check to see if CONNECT requests to the destination
856 * port of this request are forbidden. The check is
857 * independend of the actual request method.
860 * 1 : csp = Current client state (buffers, headers, etc...)
862 * Returns : True if yes, false otherwise.
864 *********************************************************************/
865 int connect_port_is_forbidden(const struct client_state *csp)
867 return ((csp->action->flags & ACTION_LIMIT_CONNECT) &&
868 !match_portlist(csp->action->string[ACTION_STRING_LIMIT_CONNECT],
873 /*********************************************************************
875 * Function : block_url
877 * Description : Called from `chat'. Check to see if we need to block this.
880 * 1 : csp = Current client state (buffers, headers, etc...)
882 * Returns : NULL => unblocked, else HTTP block response
884 *********************************************************************/
885 struct http_response *block_url(struct client_state *csp)
887 struct http_response *rsp;
888 const char *new_content_type = NULL;
891 * If it's not blocked, don't block it ;-)
893 if ((csp->action->flags & ACTION_BLOCK) == 0)
897 if (csp->action->flags & ACTION_REDIRECT)
899 log_error(LOG_LEVEL_ERROR, "redirect{} overruled by block.");
902 * Else, prepare a response
904 if (NULL == (rsp = alloc_http_response()))
906 return cgi_error_memory();
910 * If it's an image-url, send back an image or redirect
911 * as specified by the relevant +image action
913 #ifdef FEATURE_IMAGE_BLOCKING
914 if (((csp->action->flags & ACTION_IMAGE_BLOCKER) != 0)
918 /* determine HOW images should be blocked */
919 p = csp->action->string[ACTION_STRING_IMAGE_BLOCKER];
921 if(csp->action->flags & ACTION_HANDLE_AS_EMPTY_DOCUMENT)
923 log_error(LOG_LEVEL_ERROR, "handle-as-empty-document overruled by handle-as-image.");
925 #if 1 /* Two alternative strategies, use this one for now: */
927 /* and handle accordingly: */
928 if ((p == NULL) || (0 == strcmpic(p, "pattern")))
930 rsp->status = strdup("403 Request blocked by Privoxy");
931 if (rsp->status == NULL)
933 free_http_response(rsp);
934 return cgi_error_memory();
936 rsp->body = bindup(image_pattern_data, image_pattern_length);
937 if (rsp->body == NULL)
939 free_http_response(rsp);
940 return cgi_error_memory();
942 rsp->content_length = image_pattern_length;
944 if (enlist_unique_header(rsp->headers, "Content-Type", BUILTIN_IMAGE_MIMETYPE))
946 free_http_response(rsp);
947 return cgi_error_memory();
951 else if (0 == strcmpic(p, "blank"))
953 rsp->status = strdup("403 Request blocked by Privoxy");
954 if (rsp->status == NULL)
956 free_http_response(rsp);
957 return cgi_error_memory();
959 rsp->body = bindup(image_blank_data, image_blank_length);
960 if (rsp->body == NULL)
962 free_http_response(rsp);
963 return cgi_error_memory();
965 rsp->content_length = image_blank_length;
967 if (enlist_unique_header(rsp->headers, "Content-Type", BUILTIN_IMAGE_MIMETYPE))
969 free_http_response(rsp);
970 return cgi_error_memory();
976 rsp->status = strdup("302 Local Redirect from Privoxy");
977 if (rsp->status == NULL)
979 free_http_response(rsp);
980 return cgi_error_memory();
983 if (enlist_unique_header(rsp->headers, "Location", p))
985 free_http_response(rsp);
986 return cgi_error_memory();
990 #else /* Following code is disabled for now */
992 /* and handle accordingly: */
993 if ((p == NULL) || (0 == strcmpic(p, "pattern")))
995 p = CGI_PREFIX "send-banner?type=pattern";
997 else if (0 == strcmpic(p, "blank"))
999 p = CGI_PREFIX "send-banner?type=blank";
1001 rsp->status = strdup("302 Local Redirect from Privoxy");
1002 if (rsp->status == NULL)
1004 free_http_response(rsp);
1005 return cgi_error_memory();
1008 if (enlist_unique_header(rsp->headers, "Location", p))
1010 free_http_response(rsp);
1011 return cgi_error_memory();
1013 #endif /* Preceeding code is disabled for now */
1015 else if(csp->action->flags & ACTION_HANDLE_AS_EMPTY_DOCUMENT)
1018 * Send empty document.
1020 new_content_type = csp->action->string[ACTION_STRING_CONTENT_TYPE];
1023 rsp->body = strdup(" ");
1024 rsp->content_length = 1;
1026 rsp->status = strdup("403 Request blocked by Privoxy");
1027 if (rsp->status == NULL)
1029 free_http_response(rsp);
1030 return cgi_error_memory();
1032 if (new_content_type != 0)
1034 log_error(LOG_LEVEL_HEADER, "Overwriting Content-Type with %s", new_content_type);
1035 if (enlist_unique_header(rsp->headers, "Content-Type", new_content_type))
1037 free_http_response(rsp);
1038 return cgi_error_memory();
1043 #endif /* def FEATURE_IMAGE_BLOCKING */
1046 * Else, generate an HTML "blocked" message:
1050 struct map * exports;
1054 * Workaround for stupid Netscape bug which prevents
1055 * pages from being displayed if loading a referenced
1056 * JavaScript or style sheet fails. So make it appear
1057 * as if it succeeded.
1059 if ( NULL != (p = get_header_value(csp->headers, "User-Agent:"))
1060 && !strncmpic(p, "mozilla", 7) /* Catch Netscape but */
1061 && !strstr(p, "Gecko") /* save Mozilla, */
1062 && !strstr(p, "compatible") /* MSIE */
1063 && !strstr(p, "Opera")) /* and Opera. */
1065 rsp->status = strdup("200 Request for blocked URL");
1069 rsp->status = strdup("403 Request for blocked URL");
1072 if (rsp->status == NULL)
1074 free_http_response(rsp);
1075 return cgi_error_memory();
1078 exports = default_exports(csp, NULL);
1079 if (exports == NULL)
1081 free_http_response(rsp);
1082 return cgi_error_memory();
1085 #ifdef FEATURE_FORCE_LOAD
1086 err = map(exports, "force-prefix", 1, FORCE_PREFIX, 1);
1088 * Export the force conditional block killer if
1090 * - Privoxy was compiled without FEATURE_FORCE_LOAD, or
1091 * - Privoxy is configured to enforce blocks, or
1092 * - it's a CONNECT request and enforcing wouldn't work anyway.
1094 if ((csp->config->feature_flags & RUNTIME_FEATURE_ENFORCE_BLOCKS)
1095 || (0 == strcmpic(csp->http->gpc, "connect")))
1096 #endif /* ndef FEATURE_FORCE_LOAD */
1098 err = map_block_killer(exports, "force-support");
1101 if (!err) err = map(exports, "protocol", 1, csp->http->ssl ? "https://" : "http://", 1);
1102 if (!err) err = map(exports, "hostport", 1, html_encode(csp->http->hostport), 0);
1103 if (!err) err = map(exports, "path", 1, html_encode(csp->http->path), 0);
1104 if (!err) err = map(exports, "path-ue", 1, url_encode(csp->http->path), 0);
1107 const char *block_reason;
1108 if (csp->action->string[ACTION_STRING_BLOCK] != NULL)
1110 block_reason = csp->action->string[ACTION_STRING_BLOCK];
1114 assert(connect_port_is_forbidden(csp));
1115 block_reason = "Forbidden CONNECT port.";
1117 err = map(exports, "block-reason", 1, html_encode(block_reason), 0);
1122 free_http_response(rsp);
1123 return cgi_error_memory();
1126 err = template_fill_for_cgi(csp, "blocked", exports, rsp);
1129 free_http_response(rsp);
1130 return cgi_error_memory();
1133 rsp->reason = RSP_REASON_BLOCKED;
1135 return finish_http_response(csp, rsp);
1140 #ifdef FEATURE_TRUST
1141 /*********************************************************************
1143 * Function : trust_url FIXME: I should be called distrust_url
1145 * Description : Calls is_untrusted_url to determine if the URL is trusted
1146 * and if not, returns a HTTP 403 response with a reject message.
1149 * 1 : csp = Current client state (buffers, headers, etc...)
1151 * Returns : NULL => trusted, else http_response.
1153 *********************************************************************/
1154 struct http_response *trust_url(struct client_state *csp)
1156 struct http_response *rsp;
1157 struct map * exports;
1158 char buf[BUFFER_SIZE];
1160 struct url_spec **tl;
1165 * Don't bother to work on trusted URLs
1167 if (!is_untrusted_url(csp))
1173 * Else, prepare a response:
1175 if (NULL == (rsp = alloc_http_response()))
1177 return cgi_error_memory();
1180 rsp->status = strdup("403 Request blocked by Privoxy");
1181 exports = default_exports(csp, NULL);
1182 if (exports == NULL || rsp->status == NULL)
1184 free_http_response(rsp);
1185 return cgi_error_memory();
1189 * Export the protocol, host, port, and referrer information
1191 err = map(exports, "hostport", 1, csp->http->hostport, 1);
1192 if (!err) err = map(exports, "protocol", 1, csp->http->ssl ? "https://" : "http://", 1);
1193 if (!err) err = map(exports, "path", 1, csp->http->path, 1);
1195 if (NULL != (p = get_header_value(csp->headers, "Referer:")))
1197 if (!err) err = map(exports, "referrer", 1, html_encode(p), 0);
1201 if (!err) err = map(exports, "referrer", 1, "none set", 1);
1207 free_http_response(rsp);
1208 return cgi_error_memory();
1212 * Export the trust list
1215 for (tl = csp->config->trust_list; (t = *tl) != NULL ; tl++)
1217 snprintf(buf, sizeof(buf), "<li>%s</li>\n", t->spec);
1218 string_append(&p, buf);
1220 err = map(exports, "trusted-referrers", 1, p, 0);
1225 free_http_response(rsp);
1226 return cgi_error_memory();
1230 * Export the trust info, if available
1232 if (csp->config->trust_info->first)
1234 struct list_entry *l;
1237 for (l = csp->config->trust_info->first; l ; l = l->next)
1239 snprintf(buf, sizeof(buf), "<li> <a href=\"%s\">%s</a><br>\n", l->str, l->str);
1240 string_append(&p, buf);
1242 err = map(exports, "trust-info", 1, p, 0);
1246 err = map_block_killer(exports, "have-trust-info");
1252 free_http_response(rsp);
1253 return cgi_error_memory();
1257 * Export the force conditional block killer if
1259 * - Privoxy was compiled without FEATURE_FORCE_LOAD, or
1260 * - Privoxy is configured to enforce blocks, or
1261 * - it's a CONNECT request and enforcing wouldn't work anyway.
1263 #ifdef FEATURE_FORCE_LOAD
1264 if ((csp->config->feature_flags & RUNTIME_FEATURE_ENFORCE_BLOCKS)
1265 || (0 == strcmpic(csp->http->gpc, "connect")))
1267 err = map_block_killer(exports, "force-support");
1271 err = map(exports, "force-prefix", 1, FORCE_PREFIX, 1);
1273 #else /* ifndef FEATURE_FORCE_LOAD */
1274 err = map_block_killer(exports, "force-support");
1275 #endif /* ndef FEATURE_FORCE_LOAD */
1280 free_http_response(rsp);
1281 return cgi_error_memory();
1285 * Build the response
1287 err = template_fill_for_cgi(csp, "untrusted", exports, rsp);
1290 free_http_response(rsp);
1291 return cgi_error_memory();
1293 rsp->reason = RSP_REASON_UNTRUSTED;
1295 return finish_http_response(csp, rsp);
1297 #endif /* def FEATURE_TRUST */
1300 /*********************************************************************
1302 * Function : compile_dynamic_pcrs_job_list
1304 * Description : Compiles a dynamic pcrs job list (one with variables
1305 * resolved at request time)
1308 * 1 : csp = Current client state (buffers, headers, etc...)
1309 * 2 : b = The filter list to compile
1311 * Returns : NULL in case of errors, otherwise the
1314 *********************************************************************/
1315 pcrs_job *compile_dynamic_pcrs_job_list(const struct client_state *csp, const struct re_filterfile_spec *b)
1317 struct list_entry *pattern;
1318 pcrs_job *job_list = NULL;
1319 pcrs_job *dummy = NULL;
1320 pcrs_job *lastjob = NULL;
1323 const struct pcrs_variable variables[] =
1325 {"url", csp->http->url, 1},
1326 {"path", csp->http->path, 1},
1327 {"host", csp->http->host, 1},
1328 {"origin", csp->ip_addr_str, 1},
1332 for (pattern = b->patterns->first; pattern != NULL; pattern = pattern->next)
1334 assert(pattern->str != NULL);
1336 dummy = pcrs_compile_dynamic_command(pattern->str, variables, &error);
1340 log_error(LOG_LEVEL_ERROR,
1341 "Adding filter job \'%s\' to dynamic filter %s failed: %s",
1342 pattern->str, b->name, pcrs_strerror(error));
1347 if (error == PCRS_WARN_TRUNCATION)
1349 log_error(LOG_LEVEL_ERROR,
1350 "At least one of the variables in \'%s\' had to "
1351 "be truncated before compilation", pattern->str);
1353 if (job_list == NULL)
1359 lastjob->next = dummy;
1369 /*********************************************************************
1371 * Function : rewrite_url
1373 * Description : Rewrites a URL with a single pcrs command
1374 * and returns the result if it differs from the
1375 * original and isn't obviously invalid.
1378 * 1 : old_url = URL to rewrite.
1379 * 2 : pcrs_command = pcrs command formatted as string (s@foo@bar@)
1382 * Returns : NULL if the pcrs_command didn't change the url, or
1383 * the result of the modification.
1385 *********************************************************************/
1386 char *rewrite_url(char *old_url, const char *pcrs_command)
1388 char *new_url = NULL;
1392 assert(pcrs_command);
1394 new_url = pcrs_execute_single_command(old_url, pcrs_command, &hits);
1398 log_error(LOG_LEVEL_REDIRECTS,
1399 "pcrs command \"%s\" didn't change \"%s\".",
1400 pcrs_command, old_url);
1405 log_error(LOG_LEVEL_REDIRECTS,
1406 "executing pcrs command \"%s\" to rewrite %s failed: %s",
1407 pcrs_command, old_url, pcrs_strerror(hits));
1410 else if (strncmpic(new_url, "http://", 7) && strncmpic(new_url, "https://", 8))
1412 log_error(LOG_LEVEL_ERROR,
1413 "pcrs command \"%s\" changed \"%s\" to \"%s\" (%u hi%s), "
1414 "but the result doesn't look like a valid URL and will be ignored.",
1415 pcrs_command, old_url, new_url, hits, (hits == 1) ? "t" : "ts");
1420 log_error(LOG_LEVEL_REDIRECTS,
1421 "pcrs command \"%s\" changed \"%s\" to \"%s\" (%u hi%s).",
1422 pcrs_command, old_url, new_url, hits, (hits == 1) ? "t" : "ts");
1430 #ifdef FEATURE_FAST_REDIRECTS
1431 /*********************************************************************
1433 * Function : get_last_url
1435 * Description : Search for the last URL inside a string.
1436 * If the string already is a URL, it will
1437 * be the first URL found.
1440 * 1 : subject = the string to check
1441 * 2 : redirect_mode = +fast-redirect{} mode
1443 * Returns : NULL if no URL was found, or
1444 * the last URL found.
1446 *********************************************************************/
1447 char *get_last_url(char *subject, const char *redirect_mode)
1449 char *new_url = NULL;
1453 assert(redirect_mode);
1455 subject = strdup(subject);
1456 if (subject == NULL)
1458 log_error(LOG_LEVEL_ERROR, "Out of memory while searching for redirects.");
1462 if (0 == strcmpic(redirect_mode, "check-decoded-url"))
1464 log_error(LOG_LEVEL_REDIRECTS, "Decoding \"%s\" if necessary.", subject);
1465 new_url = url_decode(subject);
1466 if (new_url != NULL)
1473 log_error(LOG_LEVEL_ERROR, "Unable to decode \"%s\".", subject);
1477 log_error(LOG_LEVEL_REDIRECTS, "Checking \"%s\" for redirects.", subject);
1480 * Find the last URL encoded in the request
1483 while ((tmp = strstr(tmp, "http://")) != NULL)
1487 tmp = (new_url != NULL) ? new_url : subject;
1488 while ((tmp = strstr(tmp, "https://")) != NULL)
1493 if ((new_url != NULL)
1494 && ( (new_url != subject)
1495 || (0 == strncmpic(subject, "http://", 7))
1496 || (0 == strncmpic(subject, "https://", 8))
1500 * Return new URL if we found a redirect
1501 * or if the subject already was a URL.
1503 * The second case makes sure that we can
1504 * chain get_last_url after another redirection check
1505 * (like rewrite_url) without losing earlier redirects.
1507 new_url = strdup(new_url);
1516 #endif /* def FEATURE_FAST_REDIRECTS */
1519 /*********************************************************************
1521 * Function : redirect_url
1523 * Description : Checks if Privoxy should answer the request with
1524 * a HTTP redirect and generates the redirect if
1528 * 1 : csp = Current client state (buffers, headers, etc...)
1530 * Returns : NULL if the request can pass, HTTP redirect otherwise.
1532 *********************************************************************/
1533 struct http_response *redirect_url(struct client_state *csp)
1535 struct http_response *rsp;
1536 #ifdef FEATURE_FAST_REDIRECTS
1538 * XXX: Do we still need FEATURE_FAST_REDIRECTS
1539 * as compile-time option? The user can easily disable
1540 * it in his action file.
1542 char * redirect_mode;
1543 #endif /* def FEATURE_FAST_REDIRECTS */
1544 char *old_url = NULL;
1545 char *new_url = NULL;
1546 char *redirection_string;
1548 if ((csp->action->flags & ACTION_REDIRECT))
1550 redirection_string = csp->action->string[ACTION_STRING_REDIRECT];
1553 * If the redirection string begins with 's',
1554 * assume it's a pcrs command, otherwise treat it as
1555 * properly formatted URL and use it for the redirection
1558 * According to RFC 2616 section 14.30 the URL
1559 * has to be absolute and if the user tries:
1560 * +redirect{shit/this/will/be/parsed/as/pcrs_command.html}
1561 * she would get undefined results anyway.
1565 if (*redirection_string == 's')
1567 old_url = csp->http->url;
1568 new_url = rewrite_url(old_url, redirection_string);
1572 log_error(LOG_LEVEL_REDIRECTS,
1573 "No pcrs command recognized, assuming that \"%s\" is already properly formatted.",
1574 redirection_string);
1575 new_url = strdup(redirection_string);
1579 #ifdef FEATURE_FAST_REDIRECTS
1580 if ((csp->action->flags & ACTION_FAST_REDIRECTS))
1582 redirect_mode = csp->action->string[ACTION_STRING_FAST_REDIRECTS];
1585 * If it exists, use the previously rewritten URL as input
1586 * otherwise just use the old path.
1588 old_url = (new_url != NULL) ? new_url : strdup(csp->http->path);
1589 new_url = get_last_url(old_url, redirect_mode);
1594 * Disable redirect checkers, so that they
1595 * will be only run more than once if the user
1596 * also enables them through tags.
1598 * From a performance point of view
1599 * it doesn't matter, but the duplicated
1600 * log messages are annoying.
1602 csp->action->flags &= ~ACTION_FAST_REDIRECTS;
1603 #endif /* def FEATURE_FAST_REDIRECTS */
1604 csp->action->flags &= ~ACTION_REDIRECT;
1606 /* Did any redirect action trigger? */
1609 if (0 == strcmpic(new_url, csp->http->url))
1611 log_error(LOG_LEVEL_ERROR,
1612 "New URL \"%s\" and old URL \"%s\" are the same. Redirection loop prevented.",
1613 csp->http->url, new_url);
1618 log_error(LOG_LEVEL_REDIRECTS, "New URL is: %s", new_url);
1620 if (NULL == (rsp = alloc_http_response()))
1623 return cgi_error_memory();
1626 if ( enlist_unique_header(rsp->headers, "Location", new_url)
1627 || (NULL == (rsp->status = strdup("302 Local Redirect from Privoxy"))) )
1630 free_http_response(rsp);
1631 return cgi_error_memory();
1633 rsp->reason = RSP_REASON_REDIRECTED;
1636 return finish_http_response(csp, rsp);
1640 /* Only reached if no redirect is required */
1646 #ifdef FEATURE_IMAGE_BLOCKING
1647 /*********************************************************************
1649 * Function : is_imageurl
1651 * Description : Given a URL, decide whether it is an image or not,
1652 * using either the info from a previous +image action
1653 * or, #ifdef FEATURE_IMAGE_DETECT_MSIE, and the browser
1654 * is MSIE and not on a Mac, tell from the browser's accept
1658 * 1 : csp = Current client state (buffers, headers, etc...)
1660 * Returns : True (nonzero) if URL is an image, false (0)
1663 *********************************************************************/
1664 int is_imageurl(const struct client_state *csp)
1666 #ifdef FEATURE_IMAGE_DETECT_MSIE
1669 tmp = get_header_value(csp->headers, "User-Agent:");
1670 if (tmp && strstr(tmp, "MSIE") && !strstr(tmp, "Mac_"))
1672 tmp = get_header_value(csp->headers, "Accept:");
1673 if (tmp && strstr(tmp, "image/gif"))
1675 /* Client will accept HTML. If this seems counterintuitive,
1685 #endif /* def FEATURE_IMAGE_DETECT_MSIE */
1687 return ((csp->action->flags & ACTION_IMAGE) != 0);
1690 #endif /* def FEATURE_IMAGE_BLOCKING */
1693 #ifdef FEATURE_TRUST
1694 /*********************************************************************
1696 * Function : is_untrusted_url
1698 * Description : Should we "distrust" this URL (and block it)?
1700 * Yes if it matches a line in the trustfile, or if the
1701 * referrer matches a line starting with "+" in the
1706 * 1 : csp = Current client state (buffers, headers, etc...)
1708 * Returns : 0 => trusted, 1 => untrusted
1710 *********************************************************************/
1711 int is_untrusted_url(const struct client_state *csp)
1713 struct file_list *fl;
1714 struct block_spec *b;
1715 struct url_spec **trusted_url;
1716 struct http_request rhttp[1];
1717 const char * referer;
1721 * If we don't have a trustlist, we trust everybody
1723 if (((fl = csp->tlist) == NULL) || ((b = fl->f) == NULL))
1728 memset(rhttp, '\0', sizeof(*rhttp));
1731 * Do we trust the request URL itself?
1733 for (b = b->next; b ; b = b->next)
1735 if (url_match(b->url, csp->http))
1741 if (NULL == (referer = get_header_value(csp->headers, "Referer:")))
1743 /* no referrer was supplied */
1749 * If not, do we maybe trust its referrer?
1751 err = parse_http_url(referer, rhttp, REQUIRE_PROTOCOL);
1757 for (trusted_url = csp->config->trust_list; *trusted_url != NULL; trusted_url++)
1759 if (url_match(*trusted_url, rhttp))
1761 /* if the URL's referrer is from a trusted referrer, then
1762 * add the target spec to the trustfile as an unblocked
1763 * domain and return 0 (which means it's OK).
1768 if (NULL != (fp = fopen(csp->config->trustfile, "a")))
1772 char * new_entry = strdup("~");
1774 string_append(&new_entry, csp->http->hostport);
1776 path = csp->http->path;
1777 if ( (path[0] == '/')
1779 && ((path_end = strchr(path + 2, '/')) != NULL))
1781 /* since this path points into a user's home space
1782 * be sure to include this spec in the trustfile.
1784 int path_len = path_end - path; /* save offset */
1785 path = strdup(path); /* Copy string */
1788 path_end = path + path_len; /* regenerate ptr to new buffer */
1789 *(path_end + 1) = '\0'; /* Truncate path after '/' */
1791 string_join(&new_entry, path);
1795 * Give a reason for generating this entry.
1797 string_append(&new_entry, " # Trusted referrer was: ");
1798 string_append(&new_entry, referer);
1800 if (new_entry != NULL)
1802 if (-1 == fprintf(fp, "%s\n", new_entry))
1804 log_error(LOG_LEVEL_ERROR, "Failed to append \'%s\' to trustfile \'%s\': %E",
1805 new_entry, csp->config->trustfile);
1811 /* FIXME: No way to handle out-of memory, so mostly ignoring it */
1812 log_error(LOG_LEVEL_ERROR, "Out of memory adding pattern to trust file");
1819 log_error(LOG_LEVEL_ERROR, "Failed to append new entry for \'%s\' to trustfile \'%s\': %E",
1820 csp->http->hostport, csp->config->trustfile);
1828 #endif /* def FEATURE_TRUST */
1831 /*********************************************************************
1833 * Function : pcrs_filter_response
1835 * Description : Execute all text substitutions from all applying
1836 * +filter actions on the text buffer that's been
1837 * accumulated in csp->iob->buf.
1840 * 1 : csp = Current client state (buffers, headers, etc...)
1842 * Returns : a pointer to the (newly allocated) modified buffer.
1843 * or NULL if there were no hits or something went wrong
1845 *********************************************************************/
1846 static char *pcrs_filter_response(struct client_state *csp)
1849 size_t size, prev_size;
1855 struct file_list *fl;
1856 struct re_filterfile_spec *b;
1857 struct list_entry *filtername;
1859 int i, found_filters = 0;
1864 if (csp->iob->cur >= csp->iob->eod)
1870 * Need to check the set of re_filterfiles...
1872 for (i = 0; i < MAX_AF_FILES; i++)
1885 if (0 == found_filters)
1887 log_error(LOG_LEVEL_ERROR, "Inconsistent configuration: "
1888 "content filtering enabled, but no content filters available.");
1892 size = (size_t)(csp->iob->eod - csp->iob->cur);
1893 old = csp->iob->cur;
1895 for (i = 0; i < MAX_AF_FILES; i++)
1898 if ((NULL == fl) || (NULL == fl->f))
1901 * Either there are no filter files
1902 * left, or this filter file just
1903 * contains no valid filters.
1905 * Continue to be sure we don't miss
1906 * valid filter files that are chained
1907 * after empty or invalid ones.
1912 * For all applying +filter actions, look if a filter by that
1913 * name exists and if yes, execute it's pcrs_joblist on the
1916 for (b = fl->f; b; b = b->next)
1918 if (b->type != FT_CONTENT_FILTER)
1920 /* Skip header filters */
1924 for (filtername = csp->action->multi[ACTION_MULTI_FILTER]->first;
1925 filtername ; filtername = filtername->next)
1927 if (strcmp(b->name, filtername->str) == 0)
1929 int current_hits = 0; /* Number of hits caused by this filter */
1930 int job_number = 0; /* Which job we're currently executing */
1931 int job_hits = 0; /* How many hits the current job caused */
1932 pcrs_job *joblist = b->joblist;
1934 if (b->dynamic) joblist = compile_dynamic_pcrs_job_list(csp, b);
1936 if (NULL == joblist)
1938 log_error(LOG_LEVEL_RE_FILTER, "Filter %s has empty joblist. Nothing to do.", b->name);
1943 /* Apply all jobs from the joblist */
1944 for (job = joblist; NULL != job; job = job->next)
1947 job_hits = pcrs_execute(job, old, size, &new, &size);
1952 * That went well. Continue filtering
1953 * and use the result of this job as
1954 * input for the next one.
1956 current_hits += job_hits;
1957 if (old != csp->iob->cur)
1966 * This job caused an unexpected error. Inform the user
1967 * and skip the rest of the jobs in this filter. We could
1968 * continue with the next job, but usually the jobs
1969 * depend on each other or are similar enough to
1970 * fail for the same reason.
1972 * At the moment our pcrs expects the error codes of pcre 3.4,
1973 * but newer pcre versions can return additional error codes.
1974 * As a result pcrs_strerror()'s error message might be
1975 * "Unknown error ...", therefore we print the numerical value
1978 * XXX: Is this important enough for LOG_LEVEL_ERROR or
1979 * should we use LOG_LEVEL_RE_FILTER instead?
1981 log_error(LOG_LEVEL_ERROR, "Skipped filter \'%s\' after job number %u: %s (%d)",
1982 b->name, job_number, pcrs_strerror(job_hits), job_hits);
1987 if (b->dynamic) pcrs_free_joblist(joblist);
1989 log_error(LOG_LEVEL_RE_FILTER,
1990 "filtering %s%s (size %d) with \'%s\' produced %d hits (new size %d).",
1991 csp->http->hostport, csp->http->path, prev_size, b->name, current_hits, size);
1993 hits += current_hits;
2000 * If there were no hits, destroy our copy and let
2001 * chat() use the original in csp->iob
2009 csp->flags |= CSP_FLAG_MODIFIED;
2010 csp->content_length = size;
2018 /*********************************************************************
2020 * Function : gif_deanimate_response
2022 * Description : Deanimate the GIF image that has been accumulated in
2023 * csp->iob->buf, set csp->content_length to the modified
2024 * size and raise the CSP_FLAG_MODIFIED flag.
2027 * 1 : csp = Current client state (buffers, headers, etc...)
2029 * Returns : a pointer to the (newly allocated) modified buffer.
2030 * or NULL in case something went wrong.
2032 *********************************************************************/
2033 static char *gif_deanimate_response(struct client_state *csp)
2035 struct binbuffer *in, *out;
2039 size = (size_t)(csp->iob->eod - csp->iob->cur);
2041 if ( (NULL == (in = (struct binbuffer *)zalloc(sizeof *in )))
2042 || (NULL == (out = (struct binbuffer *)zalloc(sizeof *out))) )
2044 log_error(LOG_LEVEL_DEANIMATE, "failed! (no mem)");
2048 in->buffer = csp->iob->cur;
2051 if (gif_deanimate(in, out, strncmp("last", csp->action->string[ACTION_STRING_DEANIMATE], 4)))
2053 log_error(LOG_LEVEL_DEANIMATE, "failed! (gif parsing)");
2060 if ((int)size == out->offset)
2062 log_error(LOG_LEVEL_DEANIMATE, "GIF not changed.");
2066 log_error(LOG_LEVEL_DEANIMATE, "Success! GIF shrunk from %d bytes to %d.", size, out->offset);
2068 csp->content_length = out->offset;
2069 csp->flags |= CSP_FLAG_MODIFIED;
2079 /*********************************************************************
2081 * Function : get_filter_function
2083 * Description : Decides which content filter function has
2084 * to be applied (if any).
2087 * 1 : csp = Current client state (buffers, headers, etc...)
2089 * Returns : The content filter function to run, or
2090 * NULL if no content filter is active
2092 *********************************************************************/
2093 filter_function_ptr get_filter_function(struct client_state *csp)
2095 filter_function_ptr filter_function = NULL;
2098 * Are we enabling text mode by force?
2100 if (csp->action->flags & ACTION_FORCE_TEXT_MODE)
2103 * Do we really have to?
2105 if (csp->content_type & CT_TEXT)
2107 log_error(LOG_LEVEL_HEADER, "Text mode is already enabled.");
2111 csp->content_type |= CT_TEXT;
2112 log_error(LOG_LEVEL_HEADER, "Text mode enabled by force. Take cover!");
2116 if (!(csp->content_type & CT_DECLARED))
2119 * The server didn't bother to declare a MIME-Type.
2120 * Assume it's text that can be filtered.
2122 * This also regulary happens with 304 responses,
2123 * therefore logging anything here would cause
2126 csp->content_type |= CT_TEXT;
2130 * Choose the applying filter function based on
2131 * the content type and action settings.
2133 if ((csp->content_type & CT_TEXT) &&
2134 (csp->rlist != NULL) &&
2135 (!list_is_empty(csp->action->multi[ACTION_MULTI_FILTER])))
2137 filter_function = pcrs_filter_response;
2139 else if ((csp->content_type & CT_GIF) &&
2140 (csp->action->flags & ACTION_DEANIMATE))
2142 filter_function = gif_deanimate_response;
2145 return filter_function;
2149 /*********************************************************************
2151 * Function : remove_chunked_transfer_coding
2153 * Description : In-situ remove the "chunked" transfer coding as defined
2154 * in rfc2616 from a buffer.
2157 * 1 : buffer = Pointer to the text buffer
2158 * 2 : size = In: Number of bytes to be processed,
2159 * Out: Number of bytes after de-chunking.
2160 * (undefined in case of errors)
2162 * Returns : JB_ERR_OK for success,
2163 * JB_ERR_PARSE otherwise
2165 *********************************************************************/
2166 static jb_err remove_chunked_transfer_coding(char *buffer, size_t *size)
2169 unsigned int chunksize = 0;
2170 char *from_p, *to_p;
2173 from_p = to_p = buffer;
2175 if (sscanf(buffer, "%x", &chunksize) != 1)
2177 log_error(LOG_LEVEL_ERROR, "Invalid first chunksize while stripping \"chunked\" transfer coding");
2178 return JB_ERR_PARSE;
2181 while (chunksize > 0)
2183 if (NULL == (from_p = strstr(from_p, "\r\n")))
2185 log_error(LOG_LEVEL_ERROR, "Parse error while stripping \"chunked\" transfer coding");
2186 return JB_ERR_PARSE;
2189 if ((newsize += chunksize) >= *size)
2191 log_error(LOG_LEVEL_ERROR,
2192 "Chunk size %d exceeds buffer size %d in \"chunked\" transfer coding",
2194 return JB_ERR_PARSE;
2198 memmove(to_p, from_p, (size_t) chunksize);
2199 to_p = buffer + newsize;
2200 from_p += chunksize + 2;
2202 if (sscanf(from_p, "%x", &chunksize) != 1)
2204 log_error(LOG_LEVEL_INFO, "Invalid \"chunked\" transfer encoding detected and ignored.");
2209 /* XXX: Should get its own loglevel. */
2210 log_error(LOG_LEVEL_RE_FILTER, "De-chunking successful. Shrunk from %d to %d", *size, newsize);
2219 /*********************************************************************
2221 * Function : prepare_for_filtering
2223 * Description : If necessary, de-chunks and decompresses
2224 * the content so it can get filterd.
2227 * 1 : csp = Current client state (buffers, headers, etc...)
2229 * Returns : JB_ERR_OK for success,
2230 * JB_ERR_PARSE otherwise
2232 *********************************************************************/
2233 static jb_err prepare_for_filtering(struct client_state *csp)
2235 jb_err err = JB_ERR_OK;
2238 * If the body has a "chunked" transfer-encoding,
2239 * get rid of it, adjusting size and iob->eod
2241 if (csp->flags & CSP_FLAG_CHUNKED)
2243 size_t size = (size_t)(csp->iob->eod - csp->iob->cur);
2245 log_error(LOG_LEVEL_RE_FILTER, "Need to de-chunk first");
2246 err = remove_chunked_transfer_coding(csp->iob->cur, &size);
2247 if (JB_ERR_OK == err)
2249 csp->iob->eod = csp->iob->cur + size;
2250 csp->flags |= CSP_FLAG_MODIFIED;
2254 return JB_ERR_PARSE;
2260 * If the body has a supported transfer-encoding,
2261 * decompress it, adjusting size and iob->eod.
2263 if (csp->content_type & (CT_GZIP|CT_DEFLATE))
2265 if (0 == csp->iob->eod - csp->iob->cur)
2267 /* Nothing left after de-chunking. */
2271 err = decompress_iob(csp);
2273 if (JB_ERR_OK == err)
2275 csp->flags |= CSP_FLAG_MODIFIED;
2276 csp->content_type &= ~CT_TABOO;
2281 * Unset CT_GZIP and CT_DEFLATE to remember not
2282 * to modify the Content-Encoding header later.
2284 csp->content_type &= ~CT_GZIP;
2285 csp->content_type &= ~CT_DEFLATE;
2294 /*********************************************************************
2296 * Function : execute_content_filter
2298 * Description : Executes a given content filter.
2301 * 1 : csp = Current client state (buffers, headers, etc...)
2302 * 2 : content_filter = The filter function to execute
2304 * Returns : Pointer to the modified buffer, or
2305 * NULL if filtering failed or wasn't necessary.
2307 *********************************************************************/
2308 char *execute_content_filter(struct client_state *csp, filter_function_ptr content_filter)
2310 if (0 == csp->iob->eod - csp->iob->cur)
2313 * No content (probably status code 301, 302 ...),
2314 * no filtering necessary.
2319 if (JB_ERR_OK != prepare_for_filtering(csp))
2322 * failed to de-chunk or decompress.
2327 if (0 == csp->iob->eod - csp->iob->cur)
2330 * Clown alarm: chunked and/or compressed nothing delivered.
2335 return ((*content_filter)(csp));
2339 /*********************************************************************
2341 * Function : get_url_actions
2343 * Description : Gets the actions for this URL.
2346 * 1 : csp = Current client state (buffers, headers, etc...)
2347 * 2 : http = http_request request for blocked URLs
2351 *********************************************************************/
2352 void get_url_actions(struct client_state *csp, struct http_request *http)
2354 struct file_list *fl;
2355 struct url_actions *b;
2358 init_current_action(csp->action);
2360 for (i = 0; i < MAX_AF_FILES; i++)
2362 if (((fl = csp->actions_list[i]) == NULL) || ((b = fl->f) == NULL))
2367 apply_url_actions(csp->action, http, b);
2374 /*********************************************************************
2376 * Function : apply_url_actions
2378 * Description : Applies a list of URL actions.
2381 * 1 : action = Destination.
2382 * 2 : http = Current URL
2383 * 3 : b = list of URL actions to apply
2387 *********************************************************************/
2388 void apply_url_actions(struct current_action_spec *action,
2389 struct http_request *http,
2390 struct url_actions *b)
2394 /* Should never happen */
2398 for (b = b->next; NULL != b; b = b->next)
2400 if (url_match(b->url, http))
2402 merge_current_action(action, b->action);
2408 /*********************************************************************
2410 * Function : get_forward_override_settings
2412 * Description : Returns forward settings as specified with the
2413 * forward-override{} action. forward-override accepts
2414 * forward lines similar to the one used in the
2415 * configuration file, but without the URL pattern.
2421 * in the configuration file can be replaced with
2422 * the action section:
2424 * {+forward-override{forward .}}
2428 * 1 : csp = Current client state (buffers, headers, etc...)
2430 * Returns : Pointer to forwarding structure in case of success.
2431 * Invalid syntax is fatal.
2433 *********************************************************************/
2434 const static struct forward_spec *get_forward_override_settings(struct client_state *csp)
2436 const char *forward_override_line = csp->action->string[ACTION_STRING_FORWARD_OVERRIDE];
2437 char forward_settings[BUFFER_SIZE];
2438 char *http_parent = NULL;
2439 /* variable names were chosen for consistency reasons. */
2440 struct forward_spec *fwd = NULL;
2444 assert(csp->action->flags & ACTION_FORWARD_OVERRIDE);
2445 /* Should be enforced by load_one_actions_file() */
2446 assert(strlen(forward_override_line) < sizeof(forward_settings) - 1);
2448 /* Create a copy ssplit can modify */
2449 strlcpy(forward_settings, forward_override_line, sizeof(forward_settings));
2451 if (NULL != csp->fwd)
2454 * XXX: Currently necessary to prevent memory
2455 * leaks when the show-url-info cgi page is visited.
2457 unload_forward_spec(csp->fwd);
2461 * allocate a new forward node, valid only for
2462 * the lifetime of this request. Save its location
2463 * in csp as well, so sweep() can free it later on.
2465 fwd = csp->fwd = zalloc(sizeof(*fwd));
2468 log_error(LOG_LEVEL_FATAL,
2469 "can't allocate memory for forward-override{%s}", forward_override_line);
2470 /* Never get here - LOG_LEVEL_FATAL causes program exit */
2473 vec_count = ssplit(forward_settings, " \t", vec, SZ(vec), 1, 1);
2474 if ((vec_count == 2) && !strcasecmp(vec[0], "forward"))
2476 fwd->type = SOCKS_NONE;
2478 /* Parse the parent HTTP proxy host:port */
2479 http_parent = vec[1];
2482 else if (vec_count == 3)
2484 char *socks_proxy = NULL;
2486 if (!strcasecmp(vec[0], "forward-socks4"))
2488 fwd->type = SOCKS_4;
2489 socks_proxy = vec[1];
2491 else if (!strcasecmp(vec[0], "forward-socks4a"))
2493 fwd->type = SOCKS_4A;
2494 socks_proxy = vec[1];
2496 else if (!strcasecmp(vec[0], "forward-socks5"))
2498 fwd->type = SOCKS_5;
2499 socks_proxy = vec[1];
2502 if (NULL != socks_proxy)
2504 /* Parse the SOCKS proxy host[:port] */
2505 fwd->gateway_host = strdup(socks_proxy);
2507 if (NULL != (socks_proxy = strchr(fwd->gateway_host, ':')))
2509 *socks_proxy++ = '\0';
2510 fwd->gateway_port = strtol(socks_proxy, NULL, 0);
2513 if (fwd->gateway_port <= 0)
2515 fwd->gateway_port = 1080;
2518 http_parent = vec[2];
2522 if (NULL == http_parent)
2524 log_error(LOG_LEVEL_FATAL,
2525 "Invalid forward-override syntax in: %s", forward_override_line);
2526 /* Never get here - LOG_LEVEL_FATAL causes program exit */
2529 /* Parse http forwarding settings */
2530 if (strcmp(http_parent, ".") != 0)
2532 fwd->forward_host = strdup(http_parent);
2534 if (NULL != (http_parent = strchr(fwd->forward_host, ':')))
2536 *http_parent++ = '\0';
2537 fwd->forward_port = strtol(http_parent, NULL, 0);
2540 if (fwd->forward_port <= 0)
2542 fwd->forward_port = 8000;
2546 assert (NULL != fwd);
2548 log_error(LOG_LEVEL_CONNECT,
2549 "Overriding forwarding settings based on \'%s\'", forward_override_line);
2555 /*********************************************************************
2557 * Function : forward_url
2559 * Description : Should we forward this to another proxy?
2562 * 1 : csp = Current client state (buffers, headers, etc...)
2563 * 2 : http = http_request request for current URL
2565 * Returns : Pointer to forwarding information.
2567 *********************************************************************/
2568 const struct forward_spec *forward_url(struct client_state *csp,
2569 const struct http_request *http)
2571 static const struct forward_spec fwd_default[1] = { FORWARD_SPEC_INITIALIZER };
2572 struct forward_spec *fwd = csp->config->forward;
2574 if (csp->action->flags & ACTION_FORWARD_OVERRIDE)
2576 return get_forward_override_settings(csp);
2586 if (url_match(fwd->url, http))
2597 /*********************************************************************
2599 * Function : direct_response
2601 * Description : Check if Max-Forwards == 0 for an OPTIONS or TRACE
2602 * request and if so, return a HTTP 501 to the client.
2604 * FIXME: I have a stupid name and I should handle the
2605 * requests properly. Still, what we do here is rfc-
2606 * compliant, whereas ignoring or forwarding are not.
2609 * 1 : csp = Current client state (buffers, headers, etc...)
2611 * Returns : http_response if , NULL if nonmatch or handler fail
2613 *********************************************************************/
2614 struct http_response *direct_response(struct client_state *csp)
2616 struct http_response *rsp;
2617 struct list_entry *p;
2619 if ((0 == strcmpic(csp->http->gpc, "trace"))
2620 || (0 == strcmpic(csp->http->gpc, "options")))
2622 for (p = csp->headers->first; (p != NULL) ; p = p->next)
2624 if (!strncmpic("Max-Forwards:", p->str, 13))
2626 unsigned int max_forwards;
2629 * If it's a Max-Forwards value of zero,
2630 * we have to intercept the request.
2632 if (1 == sscanf(p->str+12, ": %u", &max_forwards) && max_forwards == 0)
2635 * FIXME: We could handle at least TRACE here,
2636 * but that would require a verbatim copy of
2637 * the request which we don't have anymore
2639 log_error(LOG_LEVEL_HEADER,
2640 "Detected header \'%s\' in OPTIONS or TRACE request. Returning 501.",
2643 /* Get mem for response or fail*/
2644 if (NULL == (rsp = alloc_http_response()))
2646 return cgi_error_memory();
2649 if (NULL == (rsp->status = strdup("501 Not Implemented")))
2651 free_http_response(rsp);
2652 return cgi_error_memory();
2656 rsp->reason = RSP_REASON_UNSUPPORTED;
2658 return(finish_http_response(csp, rsp));
2667 /*********************************************************************
2669 * Function : content_filters_enabled
2671 * Description : Checks whether there are any content filters
2672 * enabled for the current request.
2675 * 1 : action = Action spec to check.
2677 * Returns : TRUE for yes, FALSE otherwise
2679 *********************************************************************/
2680 int content_filters_enabled(const struct current_action_spec *action)
2682 return ((action->flags & ACTION_DEANIMATE) ||
2683 !list_is_empty(action->multi[ACTION_MULTI_FILTER]));