1 const char filters_rcs[] = "$Id: filters.c,v 1.103 2008/03/06 16:33:45 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 * `jpeg_inspect_response', `execute_single_pcrs_command',
14 * `rewrite_url', `get_last_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 1.103 2008/03/06 16:33:45 fabiankeil
44 * If limit-connect isn't used, don't limit CONNECT requests to port 443.
46 * Revision 1.102 2008/03/01 14:00:44 fabiankeil
47 * Let the block action take the reason for the block
48 * as argument and show it on the "blocked" page.
50 * Revision 1.101 2008/02/23 16:57:12 fabiankeil
51 * Rename url_actions() to get_url_actions() and let it
52 * use the standard parameter ordering.
54 * Revision 1.100 2008/02/23 16:33:43 fabiankeil
55 * Let forward_url() use the standard parameter ordering
56 * and mark its second parameter immutable.
58 * Revision 1.99 2008/02/03 13:57:58 fabiankeil
59 * Add SOCKS5 support for forward-override{}.
61 * Revision 1.98 2008/01/04 17:43:45 fabiankeil
62 * Improve the warning messages that get logged if the action files
63 * "enable" filters but no filters of that type have been loaded.
65 * Revision 1.97 2007/11/30 15:37:03 fabiankeil
66 * Use freez instead of free.
68 * Revision 1.96 2007/10/19 16:53:28 fabiankeil
69 * Add helper function to check if any content filters are enabled.
71 * Revision 1.95 2007/10/17 19:31:20 fabiankeil
72 * Omitting the zero chunk that ends the chunk transfer encoding seems
73 * to be the new black. Log the problem and continue filtering anyway.
75 * Revision 1.94 2007/09/29 13:20:20 fabiankeil
76 * Remove two redundant and one useless log messages.
78 * Revision 1.93 2007/09/29 10:21:16 fabiankeil
79 * - Move get_filter_function() from jcc.c to filters.c
80 * so the filter functions can be static.
81 * - Don't bother filtering body-less responses.
83 * Revision 1.92 2007/09/28 16:38:55 fabiankeil
84 * - Execute content filters through execute_content_filter().
85 * - Add prepare_for_filtering() so filter functions don't have to
86 * care about de-chunking and decompression. As a side effect this enables
87 * decompression for gif_deanimate_response() and jpeg_inspect_response().
88 * - Change remove_chunked_transfer_coding()'s return type to jb_err.
89 * Some clowns feel like chunking empty responses in which case
90 * (size == 0) is valid but previously would be interpreted as error.
92 * Revision 1.91 2007/09/02 15:31:20 fabiankeil
93 * Move match_portlist() from filter.c to urlmatch.c.
94 * It's used for url matching, not for filtering.
96 * Revision 1.90 2007/09/02 12:44:17 fabiankeil
97 * Remove newline at the end of a log_error() message.
99 * Revision 1.89 2007/08/05 13:42:23 fabiankeil
100 * #1763173 from Stefan Huehner: declare some more functions static.
102 * Revision 1.88 2007/06/01 16:41:11 fabiankeil
103 * Add forward-override{} to change the forwarding settings through
104 * action sections. This is mainly interesting to forward different
105 * clients differently (for example based on User-Agent or request
108 * Revision 1.87 2007/04/30 15:53:10 fabiankeil
109 * Make sure filters with dynamic jobs actually use them.
111 * Revision 1.86 2007/04/30 15:03:28 fabiankeil
112 * - Introduce dynamic pcrs jobs that can resolve variables.
113 * - Don't run redirect functions more than once,
114 * unless they are activated more than once.
116 * Revision 1.85 2007/03/21 12:24:47 fabiankeil
117 * - Log the content size after decompression in decompress_iob()
118 * instead of pcrs_filter_response().
120 * Revision 1.84 2007/03/20 15:16:34 fabiankeil
121 * Use dedicated header filter actions instead of abusing "filter".
122 * Replace "filter-client-headers" and "filter-client-headers"
123 * with "server-header-filter" and "client-header-filter".
125 * Revision 1.83 2007/03/17 15:20:05 fabiankeil
126 * New config option: enforce-blocks.
128 * Revision 1.82 2007/03/13 11:28:43 fabiankeil
129 * - Fix port handling in acl_addr() and use a temporary acl spec
130 * copy so error messages don't contain a truncated version.
131 * - Log size of iob before and after decompression.
133 * Revision 1.81 2007/03/05 14:40:53 fabiankeil
134 * - Cosmetical changes for LOG_LEVEL_RE_FILTER messages.
135 * - Hide the "Go there anyway" link for blocked CONNECT
136 * requests where going there anyway doesn't work anyway.
138 * Revision 1.80 2007/02/07 10:55:20 fabiankeil
139 * - Save the reason for generating http_responses.
140 * - Block (+block) with status code 403 instead of 404.
141 * - Use a different kludge to remember a failed decompression.
143 * Revision 1.79 2007/01/31 16:21:38 fabiankeil
144 * Search for Max-Forwards headers case-insensitive,
145 * don't generate the "501 unsupported" message for invalid
146 * Max-Forwards values and don't increase negative ones.
148 * Revision 1.78 2007/01/28 13:41:18 fabiankeil
149 * - Add HEAD support to finish_http_response.
150 * - Add error favicon to internal HTML error messages.
152 * Revision 1.77 2007/01/12 15:36:44 fabiankeil
153 * Mark *csp as immutable for is_untrusted_url()
154 * and is_imageurl(). Closes FR 1237736.
156 * Revision 1.76 2007/01/01 19:36:37 fabiankeil
157 * Integrate a modified version of Wil Mahan's
158 * zlib patch (PR #895531).
160 * Revision 1.75 2006/12/29 18:30:46 fabiankeil
161 * Fixed gcc43 conversion warnings,
162 * changed sprintf calls to snprintf.
164 * Revision 1.74 2006/12/24 17:37:38 fabiankeil
165 * Adjust comment in pcrs_filter_response()
166 * to recent pcrs changes. Hohoho.
168 * Revision 1.73 2006/12/23 16:01:02 fabiankeil
169 * Don't crash if pcre returns an error code
170 * that pcrs didn't expect. Fixes BR 1621173.
172 * Revision 1.72 2006/12/22 18:52:53 fabiankeil
173 * Modified is_untrusted_url to complain in case of
174 * write errors and to give a reason when adding new
175 * entries to the trustfile. Closes FR 1097611.
177 * Revision 1.71 2006/12/22 14:24:52 fabiankeil
178 * Skip empty filter files in pcrs_filter_response,
179 * but don't ignore the ones that come afterwards.
180 * Fixes parts of BR 1619208.
182 * Revision 1.70 2006/12/09 13:33:15 fabiankeil
183 * Added some sanity checks for get_last_url().
184 * Fixed possible segfault caused by my last commit.
186 * Revision 1.69 2006/12/08 12:39:13 fabiankeil
187 * Let get_last_url() catch https URLs as well.
189 * Revision 1.68 2006/12/05 14:45:48 fabiankeil
190 * Make sure get_last_url() behaves like advertised
191 * and fast-redirects{} can be combined with redirect{}.
193 * Revision 1.67 2006/11/28 15:19:43 fabiankeil
194 * Implemented +redirect{s@foo@bar@} to generate
195 * a redirect based on a rewritten version of the
198 * Revision 1.66 2006/09/23 13:26:38 roro
199 * Replace TABs by spaces in source code.
201 * Revision 1.65 2006/09/21 12:54:43 fabiankeil
202 * Fix +redirect{}. Didn't work with -fast-redirects.
204 * Revision 1.64 2006/08/31 10:55:49 fabiankeil
205 * Block requests for untrusted URLs with status
206 * code 403 instead of 200.
208 * Revision 1.63 2006/08/31 10:11:28 fabiankeil
209 * Don't free p which is still in use and will be later
210 * freed by free_map(). Don't claim the referrer is unknown
211 * when the client didn't set one.
213 * Revision 1.62 2006/08/14 00:27:47 david__schmidt
214 * Feature request 595948: Re-Filter logging in single line
216 * Revision 1.61 2006/08/03 02:46:41 david__schmidt
217 * Incorporate Fabian Keil's patch work:
\rhttp://www.fabiankeil.de/sourcecode/privoxy/
219 * Revision 1.60 2006/07/18 14:48:46 david__schmidt
220 * Reorganizing the repository: swapping out what was HEAD (the old 3.1 branch)
221 * with what was really the latest development (the v_3_0_branch branch)
223 * Revision 1.58.2.9 2006/01/29 23:10:56 david__schmidt
224 * Multiple filter file support
226 * Revision 1.58.2.8 2005/05/07 21:50:55 david__schmidt
227 * A few memory leaks plugged (mostly on error paths)
229 * Revision 1.58.2.7 2004/10/03 12:53:32 david__schmidt
230 * Add the ability to check jpeg images for invalid
231 * lengths of comment blocks. Defensive strategy
232 * against the exploit:
233 * Microsoft Security Bulletin MS04-028
234 * Buffer Overrun in JPEG Processing (GDI+) Could
235 * Allow Code Execution (833987)
236 * Enabled with +inspect-jpegs in actions files.
238 * Revision 1.58.2.6 2003/12/06 22:18:27 gliptak
239 * Correcting compile problem with FEATURE_IMAGE_BLOCKING
241 * Revision 1.58.2.5 2003/11/11 13:10:31 oes
242 * Fixed bug #839859: "See why" link URL now gets url-encoded.
244 * Revision 1.58.2.4 2003/02/28 12:52:45 oes
247 * Revision 1.58.2.3 2002/09/25 14:51:51 oes
248 * Added basic support for OPTIONS and TRACE HTTP methods:
249 * New function direct_response which handles OPTIONS and
250 * TRACE requests whose Max-Forwards header field is zero.
252 * Revision 1.58.2.2 2002/08/01 17:18:28 oes
253 * Fixed BR 537651 / SR 579724 (MSIE image detect improper for IE/Mac)
255 * Revision 1.58.2.1 2002/07/26 15:18:53 oes
256 * - Bugfix: Executing a filters without jobs no longer results in
257 * turing off *all* filters.
258 * - Security fix: Malicious web servers can't cause a seg fault
259 * through bogus chunk sizes anymore
261 * Revision 1.58 2002/04/24 02:11:17 oes
262 * Jon's multiple AF patch: url_actions now evaluates rules
265 * Revision 1.57 2002/04/08 20:38:34 swa
268 * Revision 1.56 2002/04/05 15:51:24 oes
269 * - bugfix: error-pages now get correct request protocol
270 * - fix for invalid HTML in trust info
272 * Revision 1.55 2002/04/02 16:13:51 oes
273 * Fix: No "Go there anyway" for SSL
275 * Revision 1.54 2002/04/02 14:55:56 oes
276 * Bugfix: is_untrusted_url() now depends on FEATURE_TRUST, not FEATURE_COOKIE_JAR
278 * Revision 1.53 2002/03/26 22:29:54 swa
279 * we have a new homepage!
281 * Revision 1.52 2002/03/24 16:35:57 jongfoster
284 * Revision 1.51 2002/03/24 15:23:33 jongfoster
287 * Revision 1.50 2002/03/24 13:25:43 swa
288 * name change related issues
290 * Revision 1.49 2002/03/16 20:29:14 oes
293 * Revision 1.48 2002/03/13 20:25:34 oes
294 * Better logging for content filters
296 * Revision 1.47 2002/03/13 00:30:52 jongfoster
298 * Added option of always sending redirect for imageblock,
299 * currently disabled with #if 0.
301 * Revision 1.46 2002/03/12 01:42:49 oes
302 * Introduced modular filters
304 * Revision 1.45 2002/03/08 16:47:50 oes
305 * Added choice beween GIF and PNG built-in images
307 * Revision 1.44 2002/03/07 03:49:31 oes
308 * - Fixed compiler warnings etc
309 * - Changed built-in images from GIF to PNG
310 * (with regard to Unisys patent issue)
311 * - Added a 4x4 pattern PNG which is less intrusive
312 * than the logo but also clearly marks the deleted banners
314 * Revision 1.43 2002/01/22 23:51:59 jongfoster
315 * Replacing strsav() with the safer string_append().
317 * Adding missing html_encode() to error message generators. Where encoded
318 * and unencoded versions of a string were provided, removing the unencoded
321 * Revision 1.42 2002/01/17 21:00:32 jongfoster
322 * Moving all our URL and URL pattern parsing code to urlmatch.c.
324 * Using a single, simple url_match(pattern,url) function - rather than
325 * the 3-line match routine which was repeated all over the place.
327 * Renaming free_url to free_url_spec, since it frees a struct url_spec.
329 * Using parse_http_url() to parse URLs without faking a HTTP
330 * request line for parse_http_request().
332 * Revision 1.41 2001/11/13 00:14:07 jongfoster
333 * Fixing stupid bug now I've figured out what || means.
334 * (It always returns 0 or 1, not one of it's paramaters.)
336 * Revision 1.40 2001/10/26 17:37:55 oes
337 * - Re-enabled Netscape 200/404 bug workaround in block_url():
338 * - Removed OS/2 special case
339 * - Made block_url() independant from sed() having been run
340 * - Made trust_url independant from sed() having been run
341 * - Made is_imageurl independant from sed() having been run.
342 * It now checks User-Agent: and Accept: by itself.
345 * Revision 1.39 2001/10/25 03:40:48 david__schmidt
346 * Change in porting tactics: OS/2's EMX porting layer doesn't allow multiple
347 * threads to call select() simultaneously. So, it's time to do a real, live,
348 * native OS/2 port. See defines for __EMX__ (the porting layer) vs. __OS2__
349 * (native). Both versions will work, but using __OS2__ offers multi-threading.
351 * Revision 1.38 2001/10/23 21:32:33 jongfoster
352 * Adding error-checking to selected functions
354 * Revision 1.37 2001/10/22 15:33:56 david__schmidt
355 * Special-cased OS/2 out of the Netscape-abort-on-404-in-js problem in
356 * filters.c. Added a FIXME in front of the offending code. I'll gladly
357 * put in a better/more robust fix for all parties if one is presented...
358 * It seems that just returning 200 instead of 404 would pretty much fix
359 * it for everyone, but I don't know all the history of the problem.
361 * Revision 1.36 2001/10/10 16:44:16 oes
362 * Added match_portlist function
364 * Revision 1.35 2001/10/07 15:41:23 oes
365 * Replaced 6 boolean members of csp with one bitmap (csp->flags)
367 * New function remove_chunked_transfer_coding that strips chunked
368 * transfer coding to plain and is called by pcrs_filter_response
369 * and gif_deanimate_response if neccessary
371 * Improved handling of zero-change re_filter runs
373 * pcrs_filter_response and gif_deanimate_response now remove
374 * chunked transfer codeing before processing the body.
376 * Revision 1.34 2001/09/20 15:49:36 steudten
378 * Fix BUG: Change int size to size_t size in pcrs_filter_response().
379 * See cgi.c fill_template().
381 * Revision 1.33 2001/09/16 17:05:14 jongfoster
382 * Removing unused #include showarg.h
384 * Revision 1.32 2001/09/16 13:21:27 jongfoster
385 * Changes to use new list functions.
387 * Revision 1.31 2001/09/16 11:38:02 jongfoster
388 * Splitting fill_template() into 2 functions:
389 * template_load() loads the file
390 * template_fill() performs the PCRS regexps.
391 * This is because the CGI edit interface has a "table row"
392 * template which is used many times in the page - this
393 * change means it's only loaded from disk once.
395 * Revision 1.30 2001/09/16 11:00:10 jongfoster
396 * New function alloc_http_response, for symmetry with free_http_response
398 * Revision 1.29 2001/09/13 23:32:40 jongfoster
399 * Moving image data to cgi.c rather than cgi.h
400 * Fixing a GPF under Win32 (and any other OS that protects global
401 * constants from being written to).
403 * Revision 1.28 2001/09/10 10:18:51 oes
404 * Silenced compiler warnings
406 * Revision 1.27 2001/08/05 16:06:20 jongfoster
407 * Modifiying "struct map" so that there are now separate header and
408 * "map_entry" structures. This means that functions which modify a
409 * map no longer need to return a pointer to the modified map.
410 * Also, it no longer reverses the order of the entries (which may be
411 * important with some advanced template substitutions).
413 * Revision 1.26 2001/07/30 22:08:36 jongfoster
414 * Tidying up #defines:
415 * - All feature #defines are now of the form FEATURE_xxx
416 * - Permanently turned off WIN_GUI_EDIT
417 * - Permanently turned on WEBDAV and SPLIT_PROXY_ARGS
419 * Revision 1.25 2001/07/26 10:09:46 oes
420 * Made browser detection a little less naive
422 * Revision 1.24 2001/07/25 17:22:51 oes
423 * Added workaround for Netscape bug that prevents display of page when loading a component fails.
425 * Revision 1.23 2001/07/23 13:40:12 oes
426 * Fixed bug that caused document body to be dropped when pcrs joblist was empty.
428 * Revision 1.22 2001/07/18 12:29:34 oes
429 * - Made gif_deanimate_response respect
430 * csp->action->string[ACTION_STRING_DEANIMATE]
431 * - Logging cosmetics
433 * Revision 1.21 2001/07/13 13:59:53 oes
434 * - Introduced gif_deanimate_response which shares the
435 * generic content modification interface of pcrs_filter_response
436 * and acts as a wrapper to deanimate.c:gif_deanimate()
437 * - Renamed re_process_buffer to pcrs_filter_response
438 * - pcrs_filter_response now returns NULL on failiure
439 * - Removed all #ifdef PCRS
441 * Revision 1.20 2001/07/01 17:01:04 oes
442 * Added comments and missing return statement in is_untrusted_url()
444 * Revision 1.19 2001/06/29 21:45:41 oes
445 * Indentation, CRLF->LF, Tab-> Space
447 * Revision 1.18 2001/06/29 13:27:38 oes
448 * - Cleaned up, renamed and reorderd functions
449 * and improved comments
452 * - Ported to CGI platform. Now delivers
453 * http_response or NULL
454 * - Unified HTML and GIF generation (moved image detection
455 * and GIF generation here from jcc.c:chat())
456 * - Fixed HTTP status to:
457 * - 403 (Forbidden) for the "blocked" HTML message
458 * - 200 (OK) for GIF answers
459 * - 302 (Redirect) for redirect to GIF
462 * - Ported to CGI platform. Now delivers
463 * http_response or NULL
464 * - Separated detection of untrusted URL into
465 * (bool)is_untrusted_url
466 * - Added enforcement of untrusted requests
468 * - Moved redirect_url() from cgi.c to here
469 * and ported it to the CGI platform
471 * - Removed logentry from cancelled commit
473 * Revision 1.17 2001/06/09 10:55:28 jongfoster
474 * Changing BUFSIZ ==> BUFFER_SIZE
476 * Revision 1.16 2001/06/07 23:10:26 jongfoster
477 * Allowing unanchored domain patterns to back off and retry
478 * if they partially match. Optimized right-anchored patterns.
479 * Moving ACL and forward files into config file.
480 * Replacing struct gateway with struct forward_spec
482 * Revision 1.15 2001/06/03 19:12:00 oes
483 * extracted-CGI relevant stuff
485 * Revision 1.14 2001/06/01 10:30:55 oes
486 * Added optional left-anchoring to domaincmp
488 * Revision 1.13 2001/05/31 21:21:30 jongfoster
489 * Permissionsfile / actions file changes:
490 * - Changed "permission" to "action" throughout
491 * - changes to file format to allow string parameters
492 * - Moved helper functions to actions.c
494 * Revision 1.12 2001/05/31 17:35:20 oes
496 * - Enhanced domain part globbing with infix and prefix asterisk
497 * matching and optional unanchored operation
499 * Revision 1.11 2001/05/29 11:53:23 oes
500 * "See why" link added to "blocked" page
502 * Revision 1.10 2001/05/29 09:50:24 jongfoster
503 * Unified blocklist/imagelist/permissionslist.
504 * File format is still under discussion, but the internal changes
507 * Also modified interceptor behaviour:
508 * - We now intercept all URLs beginning with one of the following
509 * prefixes (and *only* these prefixes):
511 * * http://ijbswa.sf.net/config/
512 * * http://ijbswa.sourceforge.net/config/
513 * - New interceptors "home page" - go to http://i.j.b/ to see it.
514 * - Internal changes so that intercepted and fast redirect pages
515 * are not replaced with an image.
516 * - Interceptors now have the option to send a binary page direct
517 * to the client. (i.e. ijb-send-banner uses this)
518 * - Implemented show-url-info interceptor. (Which is why I needed
519 * the above interceptors changes - a typical URL is
520 * "http://i.j.b/show-url-info?url=www.somesite.com/banner.gif".
521 * The previous mechanism would not have intercepted that, and
522 * if it had been intercepted then it then it would have replaced
525 * Revision 1.9 2001/05/27 22:17:04 oes
527 * - re_process_buffer no longer writes the modified buffer
528 * to the client, which was very ugly. It now returns the
529 * buffer, which it is then written by chat.
531 * - content_length now adjusts the Content-Length: header
532 * for modified documents rather than crunch()ing it.
533 * (Length info in csp->content_length, which is 0 for
534 * unmodified documents)
536 * - For this to work, sed() is called twice when filtering.
538 * Revision 1.8 2001/05/26 17:13:28 jongfoster
539 * Filled in a function comment.
541 * Revision 1.7 2001/05/26 15:26:15 jongfoster
542 * ACL feature now provides more security by immediately dropping
543 * connections from untrusted hosts.
545 * Revision 1.6 2001/05/26 00:28:36 jongfoster
546 * Automatic reloading of config file.
547 * Removed obsolete SIGHUP support (Unix) and Reload menu option (Win32).
548 * Most of the global variables have been moved to a new
549 * struct configuration_spec, accessed through csp->config->globalname
550 * Most of the globals remaining are used by the Win32 GUI.
552 * Revision 1.5 2001/05/25 22:34:30 jongfoster
555 * Revision 1.4 2001/05/22 18:46:04 oes
557 * - Enabled filtering banners by size rather than URL
558 * by adding patterns that replace all standard banner
559 * sizes with the "Junkbuster" gif to the re_filterfile
561 * - Enabled filtering WebBugs by providing a pattern
562 * which kills all 1x1 images
564 * - Added support for PCRE_UNGREEDY behaviour to pcrs,
565 * which is selected by the (nonstandard and therefore
566 * capital) letter 'U' in the option string.
567 * It causes the quantifiers to be ungreedy by default.
568 * Appending a ? turns back to greedy (!).
570 * - Added a new interceptor ijb-send-banner, which
571 * sends back the "Junkbuster" gif. Without imagelist or
572 * MSIE detection support, or if tinygif = 1, or the
573 * URL isn't recognized as an imageurl, a lame HTML
574 * explanation is sent instead.
576 * - Added new feature, which permits blocking remote
577 * script redirects and firing back a local redirect
579 * The feature is conditionally compiled, i.e. it
580 * can be disabled with --disable-fast-redirects,
581 * plus it must be activated by a "fast-redirects"
582 * line in the config file, has its own log level
583 * and of course wants to be displayed by show-proxy-args
584 * Note: Boy, all the #ifdefs in 1001 locations and
585 * all the fumbling with configure.in and acconfig.h
586 * were *way* more work than the feature itself :-(
588 * - Because a generic redirect template was needed for
589 * this, tinygif = 3 now uses the same.
591 * - Moved GIFs, and other static HTTP response templates
596 * - Removed some >400 CRs again (Jon, you really worked
599 * Revision 1.3 2001/05/20 16:44:47 jongfoster
600 * Removing last hardcoded Junkbusters.com URLs.
602 * Revision 1.2 2001/05/20 01:21:20 jongfoster
603 * Version 2.9.4 checkin.
604 * - Merged popupfile and cookiefile, and added control over PCRS
605 * filtering, in new "permissionsfile".
606 * - Implemented LOG_LEVEL_FATAL, so that if there is a configuration
607 * file error you now get a message box (in the Win32 GUI) rather
608 * than the program exiting with no explanation.
609 * - Made killpopup use the PCRS MIME-type checking and HTTP-header
611 * - Removed tabs from "config"
612 * - Moved duplicated url parsing code in "loaders.c" to a new funcition.
613 * - Bumped up version number.
615 * Revision 1.1.1.1 2001/05/15 13:58:52 oes
616 * Initial import of version 2.9.3 source tree
619 *********************************************************************/
625 #include <sys/types.h>
634 #endif /* ndef __OS2__ */
635 #include <netinet/in.h>
637 #include <winsock2.h>
638 #endif /* ndef _WIN32 */
642 #endif /* def __OS2__ */
650 #include "jbsockets.h"
651 #include "miscutil.h"
655 #include "deanimate.h"
656 #include "urlmatch.h"
663 const char filters_h_rcs[] = FILTERS_H_VERSION;
665 /* Fix a problem with Solaris. There should be no effect on other
667 * Solaris's isspace() is a macro which uses it's argument directly
668 * as an array index. Therefore we need to make sure that high-bit
669 * characters generate +ve values, and ideally we also want to make
670 * the argument match the declared parameter type of "int".
672 #define ijb_isdigit(__X) isdigit((int)(unsigned char)(__X))
674 static jb_err remove_chunked_transfer_coding(char *buffer, size_t *size);
675 static jb_err prepare_for_filtering(struct client_state *csp);
678 /*********************************************************************
680 * Function : block_acl
682 * Description : Block this request?
683 * Decide yes or no based on ACL file.
686 * 1 : dst = The proxy or gateway address this is going to.
687 * Or NULL to check all possible targets.
688 * 2 : csp = Current client state (buffers, headers, etc...)
689 * Also includes the client IP address.
691 * Returns : 0 = FALSE (don't block) and 1 = TRUE (do block)
693 *********************************************************************/
694 int block_acl(struct access_control_addr *dst, struct client_state *csp)
696 struct access_control_list *acl = csp->config->acl;
698 /* if not using an access control list, then permit the connection */
704 /* search the list */
707 if ((csp->ip_addr_long & acl->src->mask) == acl->src->addr)
711 /* Just want to check if they have any access */
712 if (acl->action == ACL_PERMIT)
717 else if ( ((dst->addr & acl->dst->mask) == acl->dst->addr)
718 && ((dst->port == acl->dst->port) || (acl->dst->port == 0)))
720 if (acl->action == ACL_PERMIT)
738 /*********************************************************************
740 * Function : acl_addr
742 * Description : Called from `load_config' to parse an ACL address.
745 * 1 : aspec = String specifying ACL address.
746 * 2 : aca = struct access_control_addr to fill in.
748 * Returns : 0 => Ok, everything else is an error.
750 *********************************************************************/
751 int acl_addr(const char *aspec, struct access_control_addr *aca)
756 char *acl_spec = NULL;
762 * Use a temporary acl spec copy so we can log
763 * the unmodified original in case of parse errors.
765 acl_spec = strdup(aspec);
766 if (acl_spec == NULL)
768 /* XXX: This will be logged as parse error. */
772 if ((p = strchr(acl_spec, '/')) != NULL)
775 if (ijb_isdigit(*p) == 0)
780 masklength = atoi(p);
783 if ((masklength < 0) || (masklength > 32))
789 if ((p = strchr(acl_spec, ':')) != NULL)
794 port = strtol(p, &endptr, 10);
796 if (port <= 0 || port > 65535 || *endptr != '\0')
803 aca->port = (unsigned long)port;
805 aca->addr = ntohl(resolve_hostname_to_ip(acl_spec));
808 if (aca->addr == INADDR_NONE)
810 /* XXX: This will be logged as parse error. */
814 /* build the netmask */
816 for (i=1; i <= masklength ; i++)
818 aca->mask |= (1 << (32 - i));
821 /* now mask off the host portion of the ip address
822 * (i.e. save on the network portion of the address).
824 aca->addr = aca->addr & aca->mask;
829 #endif /* def FEATURE_ACL */
832 /*********************************************************************
834 * Function : connect_port_is_forbidden
836 * Description : Check to see if CONNECT requests to the destination
837 * port of this request are forbidden. The check is
838 * independend of the actual request method.
841 * 1 : csp = Current client state (buffers, headers, etc...)
843 * Returns : True if yes, false otherwise.
845 *********************************************************************/
846 int connect_port_is_forbidden(const struct client_state *csp)
848 return ((csp->action->flags & ACTION_LIMIT_CONNECT) &&
849 !match_portlist(csp->action->string[ACTION_STRING_LIMIT_CONNECT],
854 /*********************************************************************
856 * Function : block_url
858 * Description : Called from `chat'. Check to see if we need to block this.
861 * 1 : csp = Current client state (buffers, headers, etc...)
863 * Returns : NULL => unblocked, else HTTP block response
865 *********************************************************************/
866 struct http_response *block_url(struct client_state *csp)
868 struct http_response *rsp;
869 const char *new_content_type = NULL;
872 * If it's not blocked, don't block it ;-)
874 if ((csp->action->flags & ACTION_BLOCK) == 0)
878 if (csp->action->flags & ACTION_REDIRECT)
880 log_error(LOG_LEVEL_ERROR, "redirect{} overruled by block.");
883 * Else, prepare a response
885 if (NULL == (rsp = alloc_http_response()))
887 return cgi_error_memory();
891 * If it's an image-url, send back an image or redirect
892 * as specified by the relevant +image action
894 #ifdef FEATURE_IMAGE_BLOCKING
895 if (((csp->action->flags & ACTION_IMAGE_BLOCKER) != 0)
899 /* determine HOW images should be blocked */
900 p = csp->action->string[ACTION_STRING_IMAGE_BLOCKER];
902 if(csp->action->flags & ACTION_HANDLE_AS_EMPTY_DOCUMENT)
904 log_error(LOG_LEVEL_ERROR, "handle-as-empty-document overruled by handle-as-image.");
906 #if 1 /* Two alternative strategies, use this one for now: */
908 /* and handle accordingly: */
909 if ((p == NULL) || (0 == strcmpic(p, "pattern")))
911 rsp->status = strdup("403 Request blocked by Privoxy");
912 if (rsp->status == NULL)
914 free_http_response(rsp);
915 return cgi_error_memory();
917 rsp->body = bindup(image_pattern_data, image_pattern_length);
918 if (rsp->body == NULL)
920 free_http_response(rsp);
921 return cgi_error_memory();
923 rsp->content_length = image_pattern_length;
925 if (enlist_unique_header(rsp->headers, "Content-Type", BUILTIN_IMAGE_MIMETYPE))
927 free_http_response(rsp);
928 return cgi_error_memory();
932 else if (0 == strcmpic(p, "blank"))
934 rsp->status = strdup("403 Request blocked by Privoxy");
935 if (rsp->status == NULL)
937 free_http_response(rsp);
938 return cgi_error_memory();
940 rsp->body = bindup(image_blank_data, image_blank_length);
941 if (rsp->body == NULL)
943 free_http_response(rsp);
944 return cgi_error_memory();
946 rsp->content_length = image_blank_length;
948 if (enlist_unique_header(rsp->headers, "Content-Type", BUILTIN_IMAGE_MIMETYPE))
950 free_http_response(rsp);
951 return cgi_error_memory();
957 rsp->status = strdup("302 Local Redirect from Privoxy");
958 if (rsp->status == NULL)
960 free_http_response(rsp);
961 return cgi_error_memory();
964 if (enlist_unique_header(rsp->headers, "Location", p))
966 free_http_response(rsp);
967 return cgi_error_memory();
971 #else /* Following code is disabled for now */
973 /* and handle accordingly: */
974 if ((p == NULL) || (0 == strcmpic(p, "pattern")))
976 p = CGI_PREFIX "send-banner?type=pattern";
978 else if (0 == strcmpic(p, "blank"))
980 p = CGI_PREFIX "send-banner?type=blank";
982 rsp->status = strdup("302 Local Redirect from Privoxy");
983 if (rsp->status == NULL)
985 free_http_response(rsp);
986 return cgi_error_memory();
989 if (enlist_unique_header(rsp->headers, "Location", p))
991 free_http_response(rsp);
992 return cgi_error_memory();
994 #endif /* Preceeding code is disabled for now */
996 else if(csp->action->flags & ACTION_HANDLE_AS_EMPTY_DOCUMENT)
999 * Send empty document.
1001 new_content_type = csp->action->string[ACTION_STRING_CONTENT_TYPE];
1004 rsp->body = strdup(" ");
1005 rsp->content_length = 1;
1007 rsp->status = strdup("403 Request blocked by Privoxy");
1008 if (rsp->status == NULL)
1010 free_http_response(rsp);
1011 return cgi_error_memory();
1013 if (new_content_type != 0)
1015 log_error(LOG_LEVEL_HEADER, "Overwriting Content-Type with %s", new_content_type);
1016 if (enlist_unique_header(rsp->headers, "Content-Type", new_content_type))
1018 free_http_response(rsp);
1019 return cgi_error_memory();
1024 #endif /* def FEATURE_IMAGE_BLOCKING */
1027 * Else, generate an HTML "blocked" message:
1031 struct map * exports;
1035 * Workaround for stupid Netscape bug which prevents
1036 * pages from being displayed if loading a referenced
1037 * JavaScript or style sheet fails. So make it appear
1038 * as if it succeeded.
1040 if ( NULL != (p = get_header_value(csp->headers, "User-Agent:"))
1041 && !strncmpic(p, "mozilla", 7) /* Catch Netscape but */
1042 && !strstr(p, "Gecko") /* save Mozilla, */
1043 && !strstr(p, "compatible") /* MSIE */
1044 && !strstr(p, "Opera")) /* and Opera. */
1046 rsp->status = strdup("200 Request for blocked URL");
1050 rsp->status = strdup("403 Request for blocked URL");
1053 if (rsp->status == NULL)
1055 free_http_response(rsp);
1056 return cgi_error_memory();
1059 exports = default_exports(csp, NULL);
1060 if (exports == NULL)
1062 free_http_response(rsp);
1063 return cgi_error_memory();
1066 #ifdef FEATURE_FORCE_LOAD
1067 err = map(exports, "force-prefix", 1, FORCE_PREFIX, 1);
1069 * Export the force conditional block killer if
1071 * - Privoxy was compiled without FEATURE_FORCE_LOAD, or
1072 * - Privoxy is configured to enforce blocks, or
1073 * - it's a CONNECT request and enforcing wouldn't work anyway.
1075 if ((csp->config->feature_flags & RUNTIME_FEATURE_ENFORCE_BLOCKS)
1076 || (0 == strcmpic(csp->http->gpc, "connect")))
1077 #endif /* ndef FEATURE_FORCE_LOAD */
1079 err = map_block_killer(exports, "force-support");
1082 if (!err) err = map(exports, "protocol", 1, csp->http->ssl ? "https://" : "http://", 1);
1083 if (!err) err = map(exports, "hostport", 1, html_encode(csp->http->hostport), 0);
1084 if (!err) err = map(exports, "path", 1, html_encode(csp->http->path), 0);
1085 if (!err) err = map(exports, "path-ue", 1, url_encode(csp->http->path), 0);
1088 const char *block_reason;
1089 if (csp->action->string[ACTION_STRING_BLOCK] != NULL)
1091 block_reason = csp->action->string[ACTION_STRING_BLOCK];
1095 assert(connect_port_is_forbidden(csp));
1096 block_reason = "Forbidden CONNECT port.";
1098 err = map(exports, "block-reason", 1, html_encode(block_reason), 0);
1103 free_http_response(rsp);
1104 return cgi_error_memory();
1107 err = template_fill_for_cgi(csp, "blocked", exports, rsp);
1110 free_http_response(rsp);
1111 return cgi_error_memory();
1114 rsp->reason = RSP_REASON_BLOCKED;
1116 return finish_http_response(csp, rsp);
1121 #ifdef FEATURE_TRUST
1122 /*********************************************************************
1124 * Function : trust_url FIXME: I should be called distrust_url
1126 * Description : Calls is_untrusted_url to determine if the URL is trusted
1127 * and if not, returns a HTTP 403 response with a reject message.
1130 * 1 : csp = Current client state (buffers, headers, etc...)
1132 * Returns : NULL => trusted, else http_response.
1134 *********************************************************************/
1135 struct http_response *trust_url(struct client_state *csp)
1137 struct http_response *rsp;
1138 struct map * exports;
1139 char buf[BUFFER_SIZE];
1141 struct url_spec **tl;
1146 * Don't bother to work on trusted URLs
1148 if (!is_untrusted_url(csp))
1154 * Else, prepare a response:
1156 if (NULL == (rsp = alloc_http_response()))
1158 return cgi_error_memory();
1161 rsp->status = strdup("403 Request blocked by Privoxy");
1162 exports = default_exports(csp, NULL);
1163 if (exports == NULL || rsp->status == NULL)
1165 free_http_response(rsp);
1166 return cgi_error_memory();
1170 * Export the protocol, host, port, and referrer information
1172 err = map(exports, "hostport", 1, csp->http->hostport, 1);
1173 if (!err) err = map(exports, "protocol", 1, csp->http->ssl ? "https://" : "http://", 1);
1174 if (!err) err = map(exports, "path", 1, csp->http->path, 1);
1176 if (NULL != (p = get_header_value(csp->headers, "Referer:")))
1178 if (!err) err = map(exports, "referrer", 1, html_encode(p), 0);
1182 if (!err) err = map(exports, "referrer", 1, "none set", 1);
1188 free_http_response(rsp);
1189 return cgi_error_memory();
1193 * Export the trust list
1196 for (tl = csp->config->trust_list; (t = *tl) != NULL ; tl++)
1198 snprintf(buf, sizeof(buf), "<li>%s</li>\n", t->spec);
1199 string_append(&p, buf);
1201 err = map(exports, "trusted-referrers", 1, p, 0);
1206 free_http_response(rsp);
1207 return cgi_error_memory();
1211 * Export the trust info, if available
1213 if (csp->config->trust_info->first)
1215 struct list_entry *l;
1218 for (l = csp->config->trust_info->first; l ; l = l->next)
1220 snprintf(buf, sizeof(buf), "<li> <a href=\"%s\">%s</a><br>\n", l->str, l->str);
1221 string_append(&p, buf);
1223 err = map(exports, "trust-info", 1, p, 0);
1227 err = map_block_killer(exports, "have-trust-info");
1233 free_http_response(rsp);
1234 return cgi_error_memory();
1238 * Export the force conditional block killer if
1240 * - Privoxy was compiled without FEATURE_FORCE_LOAD, or
1241 * - Privoxy is configured to enforce blocks, or
1242 * - it's a CONNECT request and enforcing wouldn't work anyway.
1244 #ifdef FEATURE_FORCE_LOAD
1245 if ((csp->config->feature_flags & RUNTIME_FEATURE_ENFORCE_BLOCKS)
1246 || (0 == strcmpic(csp->http->gpc, "connect")))
1248 err = map_block_killer(exports, "force-support");
1252 err = map(exports, "force-prefix", 1, FORCE_PREFIX, 1);
1254 #else /* ifndef FEATURE_FORCE_LOAD */
1255 err = map_block_killer(exports, "force-support");
1256 #endif /* ndef FEATURE_FORCE_LOAD */
1261 free_http_response(rsp);
1262 return cgi_error_memory();
1266 * Build the response
1268 err = template_fill_for_cgi(csp, "untrusted", exports, rsp);
1271 free_http_response(rsp);
1272 return cgi_error_memory();
1274 rsp->reason = RSP_REASON_UNTRUSTED;
1276 return finish_http_response(csp, rsp);
1278 #endif /* def FEATURE_TRUST */
1281 /*********************************************************************
1283 * Function : compile_dynamic_pcrs_job_list
1285 * Description : Compiles a dynamic pcrs job list (one with variables
1286 * resolved at request time)
1289 * 1 : csp = Current client state (buffers, headers, etc...)
1290 * 2 : b = The filter list to compile
1292 * Returns : NULL in case of errors, otherwise the
1295 *********************************************************************/
1296 pcrs_job *compile_dynamic_pcrs_job_list(const struct client_state *csp, const struct re_filterfile_spec *b)
1298 struct list_entry *pattern;
1299 pcrs_job *job_list = NULL;
1300 pcrs_job *dummy = NULL;
1301 pcrs_job *lastjob = NULL;
1304 const struct pcrs_variable variables[] =
1306 {"url", csp->http->url, 1},
1307 {"path", csp->http->path, 1},
1308 {"host", csp->http->host, 1},
1309 {"origin", csp->ip_addr_str, 1},
1313 for (pattern = b->patterns->first; pattern != NULL; pattern = pattern->next)
1315 assert(pattern->str != NULL);
1317 dummy = pcrs_compile_dynamic_command(pattern->str, variables, &error);
1321 log_error(LOG_LEVEL_ERROR,
1322 "Adding filter job \'%s\' to dynamic filter %s failed: %s",
1323 pattern->str, b->name, pcrs_strerror(error));
1328 if (error == PCRS_WARN_TRUNCATION)
1330 log_error(LOG_LEVEL_ERROR,
1331 "At least one of the variables in \'%s\' had to "
1332 "be truncated before compilation", pattern->str);
1334 if (job_list == NULL)
1340 lastjob->next = dummy;
1350 /*********************************************************************
1352 * Function : rewrite_url
1354 * Description : Rewrites a URL with a single pcrs command
1355 * and returns the result if it differs from the
1356 * original and isn't obviously invalid.
1359 * 1 : old_url = URL to rewrite.
1360 * 2 : pcrs_command = pcrs command formatted as string (s@foo@bar@)
1363 * Returns : NULL if the pcrs_command didn't change the url, or
1364 * the result of the modification.
1366 *********************************************************************/
1367 char *rewrite_url(char *old_url, const char *pcrs_command)
1369 char *new_url = NULL;
1373 assert(pcrs_command);
1375 new_url = pcrs_execute_single_command(old_url, pcrs_command, &hits);
1379 log_error(LOG_LEVEL_REDIRECTS,
1380 "pcrs command \"%s\" didn't change \"%s\".",
1381 pcrs_command, old_url);
1386 log_error(LOG_LEVEL_REDIRECTS,
1387 "executing pcrs command \"%s\" to rewrite %s failed: %s",
1388 pcrs_command, old_url, pcrs_strerror(hits));
1391 else if (strncmpic(new_url, "http://", 7) && strncmpic(new_url, "https://", 8))
1393 log_error(LOG_LEVEL_ERROR,
1394 "pcrs command \"%s\" changed \"%s\" to \"%s\" (%u hi%s), "
1395 "but the result doesn't look like a valid URL and will be ignored.",
1396 pcrs_command, old_url, new_url, hits, (hits == 1) ? "t" : "ts");
1401 log_error(LOG_LEVEL_REDIRECTS,
1402 "pcrs command \"%s\" changed \"%s\" to \"%s\" (%u hi%s).",
1403 pcrs_command, old_url, new_url, hits, (hits == 1) ? "t" : "ts");
1411 #ifdef FEATURE_FAST_REDIRECTS
1412 /*********************************************************************
1414 * Function : get_last_url
1416 * Description : Search for the last URL inside a string.
1417 * If the string already is a URL, it will
1418 * be the first URL found.
1421 * 1 : subject = the string to check
1422 * 2 : redirect_mode = +fast-redirect{} mode
1424 * Returns : NULL if no URL was found, or
1425 * the last URL found.
1427 *********************************************************************/
1428 char *get_last_url(char *subject, const char *redirect_mode)
1430 char *new_url = NULL;
1434 assert(redirect_mode);
1436 subject = strdup(subject);
1437 if (subject == NULL)
1439 log_error(LOG_LEVEL_ERROR, "Out of memory while searching for redirects.");
1443 if (0 == strcmpic(redirect_mode, "check-decoded-url"))
1445 log_error(LOG_LEVEL_REDIRECTS, "Decoding \"%s\" if necessary.", subject);
1446 new_url = url_decode(subject);
1447 if (new_url != NULL)
1454 log_error(LOG_LEVEL_ERROR, "Unable to decode \"%s\".", subject);
1458 log_error(LOG_LEVEL_REDIRECTS, "Checking \"%s\" for redirects.", subject);
1461 * Find the last URL encoded in the request
1464 while ((tmp = strstr(tmp, "http://")) != NULL)
1468 tmp = (new_url != NULL) ? new_url : subject;
1469 while ((tmp = strstr(tmp, "https://")) != NULL)
1474 if ((new_url != NULL)
1475 && ( (new_url != subject)
1476 || (0 == strncmpic(subject, "http://", 7))
1477 || (0 == strncmpic(subject, "https://", 8))
1481 * Return new URL if we found a redirect
1482 * or if the subject already was a URL.
1484 * The second case makes sure that we can
1485 * chain get_last_url after another redirection check
1486 * (like rewrite_url) without losing earlier redirects.
1488 new_url = strdup(new_url);
1497 #endif /* def FEATURE_FAST_REDIRECTS */
1500 /*********************************************************************
1502 * Function : redirect_url
1504 * Description : Checks if Privoxy should answer the request with
1505 * a HTTP redirect and generates the redirect if
1509 * 1 : csp = Current client state (buffers, headers, etc...)
1511 * Returns : NULL if the request can pass, HTTP redirect otherwise.
1513 *********************************************************************/
1514 struct http_response *redirect_url(struct client_state *csp)
1516 struct http_response *rsp;
1517 #ifdef FEATURE_FAST_REDIRECTS
1519 * XXX: Do we still need FEATURE_FAST_REDIRECTS
1520 * as compile-time option? The user can easily disable
1521 * it in his action file.
1523 char * redirect_mode;
1524 #endif /* def FEATURE_FAST_REDIRECTS */
1525 char *old_url = NULL;
1526 char *new_url = NULL;
1527 char *redirection_string;
1529 if ((csp->action->flags & ACTION_REDIRECT))
1531 redirection_string = csp->action->string[ACTION_STRING_REDIRECT];
1534 * If the redirection string begins with 's',
1535 * assume it's a pcrs command, otherwise treat it as
1536 * properly formatted URL and use it for the redirection
1539 * According to RFC 2616 section 14.30 the URL
1540 * has to be absolute and if the user tries:
1541 * +redirect{shit/this/will/be/parsed/as/pcrs_command.html}
1542 * she would get undefined results anyway.
1546 if (*redirection_string == 's')
1548 old_url = csp->http->url;
1549 new_url = rewrite_url(old_url, redirection_string);
1553 log_error(LOG_LEVEL_REDIRECTS,
1554 "No pcrs command recognized, assuming that \"%s\" is already properly formatted.",
1555 redirection_string);
1556 new_url = strdup(redirection_string);
1560 #ifdef FEATURE_FAST_REDIRECTS
1561 if ((csp->action->flags & ACTION_FAST_REDIRECTS))
1563 redirect_mode = csp->action->string[ACTION_STRING_FAST_REDIRECTS];
1566 * If it exists, use the previously rewritten URL as input
1567 * otherwise just use the old path.
1569 old_url = (new_url != NULL) ? new_url : strdup(csp->http->path);
1570 new_url = get_last_url(old_url, redirect_mode);
1575 * Disable redirect checkers, so that they
1576 * will be only run more than once if the user
1577 * also enables them through tags.
1579 * From a performance point of view
1580 * it doesn't matter, but the duplicated
1581 * log messages are annoying.
1583 csp->action->flags &= ~ACTION_FAST_REDIRECTS;
1584 #endif /* def FEATURE_FAST_REDIRECTS */
1585 csp->action->flags &= ~ACTION_REDIRECT;
1587 /* Did any redirect action trigger? */
1590 if (0 == strcmpic(new_url, csp->http->url))
1592 log_error(LOG_LEVEL_ERROR,
1593 "New URL \"%s\" and old URL \"%s\" are the same. Redirection loop prevented.",
1594 csp->http->url, new_url);
1599 log_error(LOG_LEVEL_REDIRECTS, "New URL is: %s", new_url);
1601 if (NULL == (rsp = alloc_http_response()))
1604 return cgi_error_memory();
1607 if ( enlist_unique_header(rsp->headers, "Location", new_url)
1608 || (NULL == (rsp->status = strdup("302 Local Redirect from Privoxy"))) )
1611 free_http_response(rsp);
1612 return cgi_error_memory();
1614 rsp->reason = RSP_REASON_REDIRECTED;
1617 return finish_http_response(csp, rsp);
1621 /* Only reached if no redirect is required */
1627 #ifdef FEATURE_IMAGE_BLOCKING
1628 /*********************************************************************
1630 * Function : is_imageurl
1632 * Description : Given a URL, decide whether it is an image or not,
1633 * using either the info from a previous +image action
1634 * or, #ifdef FEATURE_IMAGE_DETECT_MSIE, and the browser
1635 * is MSIE and not on a Mac, tell from the browser's accept
1639 * 1 : csp = Current client state (buffers, headers, etc...)
1641 * Returns : True (nonzero) if URL is an image, false (0)
1644 *********************************************************************/
1645 int is_imageurl(const struct client_state *csp)
1647 #ifdef FEATURE_IMAGE_DETECT_MSIE
1650 tmp = get_header_value(csp->headers, "User-Agent:");
1651 if (tmp && strstr(tmp, "MSIE") && !strstr(tmp, "Mac_"))
1653 tmp = get_header_value(csp->headers, "Accept:");
1654 if (tmp && strstr(tmp, "image/gif"))
1656 /* Client will accept HTML. If this seems counterintuitive,
1666 #endif /* def FEATURE_IMAGE_DETECT_MSIE */
1668 return ((csp->action->flags & ACTION_IMAGE) != 0);
1671 #endif /* def FEATURE_IMAGE_BLOCKING */
1674 #ifdef FEATURE_TRUST
1675 /*********************************************************************
1677 * Function : is_untrusted_url
1679 * Description : Should we "distrust" this URL (and block it)?
1681 * Yes if it matches a line in the trustfile, or if the
1682 * referrer matches a line starting with "+" in the
1687 * 1 : csp = Current client state (buffers, headers, etc...)
1689 * Returns : 0 => trusted, 1 => untrusted
1691 *********************************************************************/
1692 int is_untrusted_url(const struct client_state *csp)
1694 struct file_list *fl;
1695 struct block_spec *b;
1696 struct url_spec **trusted_url;
1697 struct http_request rhttp[1];
1698 const char * referer;
1702 * If we don't have a trustlist, we trust everybody
1704 if (((fl = csp->tlist) == NULL) || ((b = fl->f) == NULL))
1709 memset(rhttp, '\0', sizeof(*rhttp));
1712 * Do we trust the request URL itself?
1714 for (b = b->next; b ; b = b->next)
1716 if (url_match(b->url, csp->http))
1722 if (NULL == (referer = get_header_value(csp->headers, "Referer:")))
1724 /* no referrer was supplied */
1730 * If not, do we maybe trust its referrer?
1732 err = parse_http_url(referer, rhttp, csp);
1738 for (trusted_url = csp->config->trust_list; *trusted_url != NULL; trusted_url++)
1740 if (url_match(*trusted_url, rhttp))
1742 /* if the URL's referrer is from a trusted referrer, then
1743 * add the target spec to the trustfile as an unblocked
1744 * domain and return 0 (which means it's OK).
1749 if (NULL != (fp = fopen(csp->config->trustfile, "a")))
1753 char * new_entry = strdup("~");
1755 string_append(&new_entry, csp->http->hostport);
1757 path = csp->http->path;
1758 if ( (path[0] == '/')
1760 && ((path_end = strchr(path + 2, '/')) != NULL))
1762 /* since this path points into a user's home space
1763 * be sure to include this spec in the trustfile.
1765 int path_len = path_end - path; /* save offset */
1766 path = strdup(path); /* Copy string */
1769 path_end = path + path_len; /* regenerate ptr to new buffer */
1770 *(path_end + 1) = '\0'; /* Truncate path after '/' */
1772 string_join(&new_entry, path);
1776 * Give a reason for generating this entry.
1778 string_append(&new_entry, " # Trusted referrer was: ");
1779 string_append(&new_entry, referer);
1781 if (new_entry != NULL)
1783 if (-1 == fprintf(fp, "%s\n", new_entry))
1785 log_error(LOG_LEVEL_ERROR, "Failed to append \'%s\' to trustfile \'%s\': %E",
1786 new_entry, csp->config->trustfile);
1792 /* FIXME: No way to handle out-of memory, so mostly ignoring it */
1793 log_error(LOG_LEVEL_ERROR, "Out of memory adding pattern to trust file");
1800 log_error(LOG_LEVEL_ERROR, "Failed to append new entry for \'%s\' to trustfile \'%s\': %E",
1801 csp->http->hostport, csp->config->trustfile);
1809 #endif /* def FEATURE_TRUST */
1812 /*********************************************************************
1814 * Function : pcrs_filter_response
1816 * Description : Execute all text substitutions from all applying
1817 * +filter actions on the text buffer that's been
1818 * accumulated in csp->iob->buf.
1821 * 1 : csp = Current client state (buffers, headers, etc...)
1823 * Returns : a pointer to the (newly allocated) modified buffer.
1824 * or NULL if there were no hits or something went wrong
1826 *********************************************************************/
1827 static char *pcrs_filter_response(struct client_state *csp)
1830 size_t size, prev_size;
1836 struct file_list *fl;
1837 struct re_filterfile_spec *b;
1838 struct list_entry *filtername;
1840 int i, found_filters = 0;
1845 if (csp->iob->cur >= csp->iob->eod)
1851 * Need to check the set of re_filterfiles...
1853 for (i = 0; i < MAX_AF_FILES; i++)
1866 if (0 == found_filters)
1868 log_error(LOG_LEVEL_ERROR, "Inconsistent configuration: "
1869 "content filtering enabled, but no content filters available.");
1873 size = (size_t)(csp->iob->eod - csp->iob->cur);
1874 old = csp->iob->cur;
1876 for (i = 0; i < MAX_AF_FILES; i++)
1879 if ((NULL == fl) || (NULL == fl->f))
1882 * Either there are no filter files
1883 * left, or this filter file just
1884 * contains no valid filters.
1886 * Continue to be sure we don't miss
1887 * valid filter files that are chained
1888 * after empty or invalid ones.
1893 * For all applying +filter actions, look if a filter by that
1894 * name exists and if yes, execute it's pcrs_joblist on the
1897 for (b = fl->f; b; b = b->next)
1899 if (b->type != FT_CONTENT_FILTER)
1901 /* Skip header filters */
1905 for (filtername = csp->action->multi[ACTION_MULTI_FILTER]->first;
1906 filtername ; filtername = filtername->next)
1908 if (strcmp(b->name, filtername->str) == 0)
1910 int current_hits = 0; /* Number of hits caused by this filter */
1911 int job_number = 0; /* Which job we're currently executing */
1912 int job_hits = 0; /* How many hits the current job caused */
1913 pcrs_job *joblist = b->joblist;
1915 if (b->dynamic) joblist = compile_dynamic_pcrs_job_list(csp, b);
1917 if (NULL == joblist)
1919 log_error(LOG_LEVEL_RE_FILTER, "Filter %s has empty joblist. Nothing to do.", b->name);
1924 /* Apply all jobs from the joblist */
1925 for (job = joblist; NULL != job; job = job->next)
1928 job_hits = pcrs_execute(job, old, size, &new, &size);
1933 * That went well. Continue filtering
1934 * and use the result of this job as
1935 * input for the next one.
1937 current_hits += job_hits;
1938 if (old != csp->iob->cur)
1947 * This job caused an unexpected error. Inform the user
1948 * and skip the rest of the jobs in this filter. We could
1949 * continue with the next job, but usually the jobs
1950 * depend on each other or are similar enough to
1951 * fail for the same reason.
1953 * At the moment our pcrs expects the error codes of pcre 3.4,
1954 * but newer pcre versions can return additional error codes.
1955 * As a result pcrs_strerror()'s error message might be
1956 * "Unknown error ...", therefore we print the numerical value
1959 * XXX: Is this important enough for LOG_LEVEL_ERROR or
1960 * should we use LOG_LEVEL_RE_FILTER instead?
1962 log_error(LOG_LEVEL_ERROR, "Skipped filter \'%s\' after job number %u: %s (%d)",
1963 b->name, job_number, pcrs_strerror(job_hits), job_hits);
1968 if (b->dynamic) pcrs_free_joblist(joblist);
1970 log_error(LOG_LEVEL_RE_FILTER,
1971 "filtering %s%s (size %d) with \'%s\' produced %d hits (new size %d).",
1972 csp->http->hostport, csp->http->path, prev_size, b->name, current_hits, size);
1974 hits += current_hits;
1981 * If there were no hits, destroy our copy and let
1982 * chat() use the original in csp->iob
1990 csp->flags |= CSP_FLAG_MODIFIED;
1991 csp->content_length = size;
1999 /*********************************************************************
2001 * Function : gif_deanimate_response
2003 * Description : Deanimate the GIF image that has been accumulated in
2004 * csp->iob->buf, set csp->content_length to the modified
2005 * size and raise the CSP_FLAG_MODIFIED flag.
2008 * 1 : csp = Current client state (buffers, headers, etc...)
2010 * Returns : a pointer to the (newly allocated) modified buffer.
2011 * or NULL in case something went wrong.
2013 *********************************************************************/
2014 static char *gif_deanimate_response(struct client_state *csp)
2016 struct binbuffer *in, *out;
2020 size = (size_t)(csp->iob->eod - csp->iob->cur);
2022 if ( (NULL == (in = (struct binbuffer *)zalloc(sizeof *in )))
2023 || (NULL == (out = (struct binbuffer *)zalloc(sizeof *out))) )
2025 log_error(LOG_LEVEL_DEANIMATE, "failed! (no mem)");
2029 in->buffer = csp->iob->cur;
2032 if (gif_deanimate(in, out, strncmp("last", csp->action->string[ACTION_STRING_DEANIMATE], 4)))
2034 log_error(LOG_LEVEL_DEANIMATE, "failed! (gif parsing)");
2041 if ((int)size == out->offset)
2043 log_error(LOG_LEVEL_DEANIMATE, "GIF not changed.");
2047 log_error(LOG_LEVEL_DEANIMATE, "Success! GIF shrunk from %d bytes to %d.", size, out->offset);
2049 csp->content_length = out->offset;
2050 csp->flags |= CSP_FLAG_MODIFIED;
2060 /*********************************************************************
2062 * Function : jpeg_inspect_response
2067 * 1 : csp = Current client state (buffers, headers, etc...)
2069 * Returns : a pointer to the (newly allocated) modified buffer
2070 * or NULL in case something went wrong.
2072 *********************************************************************/
2073 static char *jpeg_inspect_response(struct client_state *csp)
2075 struct binbuffer *in = NULL;
2076 struct binbuffer *out = NULL;
2080 size = (size_t)(csp->iob->eod - csp->iob->cur);
2082 if (NULL == (in = (struct binbuffer *)zalloc(sizeof *in )))
2084 log_error(LOG_LEVEL_DEANIMATE, "failed! (jpeg no mem 1)");
2088 if (NULL == (out = (struct binbuffer *)zalloc(sizeof *out)))
2090 log_error(LOG_LEVEL_DEANIMATE, "failed! (jpeg no mem 2)");
2094 in->buffer = csp->iob->cur;
2098 * Calling jpeg_inspect has the side-effect of creating and
2099 * modifying the image buffer of "out" directly.
2101 if (jpeg_inspect(in, out))
2103 log_error(LOG_LEVEL_DEANIMATE, "failed! (jpeg parsing)");
2111 csp->content_length = out->offset;
2112 csp->flags |= CSP_FLAG_MODIFIED;
2122 /*********************************************************************
2124 * Function : get_filter_function
2126 * Description : Decides which content filter function has
2127 * to be applied (if any).
2129 * XXX: Doesn't handle filter_popups()
2130 * because of the different prototype. Probably
2131 * we should ditch filter_popups() anyway, it's
2132 * even less reliable than popup blocking based
2136 * 1 : csp = Current client state (buffers, headers, etc...)
2138 * Returns : The content filter function to run, or
2139 * NULL if no content filter is active
2141 *********************************************************************/
2142 filter_function_ptr get_filter_function(struct client_state *csp)
2144 filter_function_ptr filter_function = NULL;
2147 * Are we enabling text mode by force?
2149 if (csp->action->flags & ACTION_FORCE_TEXT_MODE)
2152 * Do we really have to?
2154 if (csp->content_type & CT_TEXT)
2156 log_error(LOG_LEVEL_HEADER, "Text mode is already enabled.");
2160 csp->content_type |= CT_TEXT;
2161 log_error(LOG_LEVEL_HEADER, "Text mode enabled by force. Take cover!");
2165 if (!(csp->content_type & CT_DECLARED))
2168 * The server didn't bother to declare a MIME-Type.
2169 * Assume it's text that can be filtered.
2171 * This also regulary happens with 304 responses,
2172 * therefore logging anything here would cause
2175 csp->content_type |= CT_TEXT;
2179 * Choose the applying filter function based on
2180 * the content type and action settings.
2182 if ((csp->content_type & CT_TEXT) &&
2183 (csp->rlist != NULL) &&
2184 (!list_is_empty(csp->action->multi[ACTION_MULTI_FILTER])))
2186 filter_function = pcrs_filter_response;
2188 else if ((csp->content_type & CT_GIF) &&
2189 (csp->action->flags & ACTION_DEANIMATE))
2191 filter_function = gif_deanimate_response;
2193 else if ((csp->content_type & CT_JPEG) &&
2194 (csp->action->flags & ACTION_JPEG_INSPECT))
2196 filter_function = jpeg_inspect_response;
2199 return filter_function;
2203 /*********************************************************************
2205 * Function : remove_chunked_transfer_coding
2207 * Description : In-situ remove the "chunked" transfer coding as defined
2208 * in rfc2616 from a buffer.
2211 * 1 : buffer = Pointer to the text buffer
2212 * 2 : size = In: Number of bytes to be processed,
2213 * Out: Number of bytes after de-chunking.
2214 * (undefined in case of errors)
2216 * Returns : JB_ERR_OK for success,
2217 * JB_ERR_PARSE otherwise
2219 *********************************************************************/
2220 static jb_err remove_chunked_transfer_coding(char *buffer, size_t *size)
2223 unsigned int chunksize = 0;
2224 char *from_p, *to_p;
2227 from_p = to_p = buffer;
2229 if (sscanf(buffer, "%x", &chunksize) != 1)
2231 log_error(LOG_LEVEL_ERROR, "Invalid first chunksize while stripping \"chunked\" transfer coding");
2232 return JB_ERR_PARSE;
2235 while (chunksize > 0)
2237 if (NULL == (from_p = strstr(from_p, "\r\n")))
2239 log_error(LOG_LEVEL_ERROR, "Parse error while stripping \"chunked\" transfer coding");
2240 return JB_ERR_PARSE;
2243 if ((newsize += chunksize) >= *size)
2245 log_error(LOG_LEVEL_ERROR, "Chunksize exceeds buffer in \"chunked\" transfer coding");
2246 return JB_ERR_PARSE;
2250 memmove(to_p, from_p, (size_t) chunksize);
2251 to_p = buffer + newsize;
2252 from_p += chunksize + 2;
2254 if (sscanf(from_p, "%x", &chunksize) != 1)
2256 log_error(LOG_LEVEL_INFO, "Invalid \"chunked\" transfer encoding detected and ignored.");
2261 /* XXX: Should get its own loglevel. */
2262 log_error(LOG_LEVEL_RE_FILTER, "De-chunking successful. Shrunk from %d to %d", *size, newsize);
2271 /*********************************************************************
2273 * Function : prepare_for_filtering
2275 * Description : If necessary, de-chunks and decompresses
2276 * the content so it can get filterd.
2279 * 1 : csp = Current client state (buffers, headers, etc...)
2281 * Returns : JB_ERR_OK for success,
2282 * JB_ERR_PARSE otherwise
2284 *********************************************************************/
2285 static jb_err prepare_for_filtering(struct client_state *csp)
2287 jb_err err = JB_ERR_OK;
2290 * If the body has a "chunked" transfer-encoding,
2291 * get rid of it, adjusting size and iob->eod
2293 if (csp->flags & CSP_FLAG_CHUNKED)
2295 size_t size = (size_t)(csp->iob->eod - csp->iob->cur);
2297 log_error(LOG_LEVEL_RE_FILTER, "Need to de-chunk first");
2298 err = remove_chunked_transfer_coding(csp->iob->cur, &size);
2299 if (JB_ERR_OK == err)
2301 csp->iob->eod = csp->iob->cur + size;
2302 csp->flags |= CSP_FLAG_MODIFIED;
2306 return JB_ERR_PARSE;
2312 * If the body has a supported transfer-encoding,
2313 * decompress it, adjusting size and iob->eod.
2315 if (csp->content_type & (CT_GZIP|CT_DEFLATE))
2317 if (0 == csp->iob->eod - csp->iob->cur)
2319 /* Nothing left after de-chunking. */
2323 err = decompress_iob(csp);
2325 if (JB_ERR_OK == err)
2327 csp->flags |= CSP_FLAG_MODIFIED;
2328 csp->content_type &= ~CT_TABOO;
2333 * Unset CT_GZIP and CT_DEFLATE to remember not
2334 * to modify the Content-Encoding header later.
2336 csp->content_type &= ~CT_GZIP;
2337 csp->content_type &= ~CT_DEFLATE;
2346 /*********************************************************************
2348 * Function : execute_content_filter
2350 * Description : Executes a given content filter.
2353 * 1 : csp = Current client state (buffers, headers, etc...)
2354 * 2 : content_filter = The filter function to execute
2356 * Returns : Pointer to the modified buffer, or
2357 * NULL if filtering failed or wasn't necessary.
2359 *********************************************************************/
2360 char *execute_content_filter(struct client_state *csp, filter_function_ptr content_filter)
2362 if (0 == csp->iob->eod - csp->iob->cur)
2365 * No content (probably status code 301, 302 ...),
2366 * no filtering necessary.
2371 if (JB_ERR_OK != prepare_for_filtering(csp))
2374 * failed to de-chunk or decompress.
2379 if (0 == csp->iob->eod - csp->iob->cur)
2382 * Clown alarm: chunked and/or compressed nothing delivered.
2387 return ((*content_filter)(csp));
2391 /*********************************************************************
2393 * Function : get_url_actions
2395 * Description : Gets the actions for this URL.
2398 * 1 : csp = Current client state (buffers, headers, etc...)
2399 * 2 : http = http_request request for blocked URLs
2403 *********************************************************************/
2404 void get_url_actions(struct client_state *csp, struct http_request *http)
2406 struct file_list *fl;
2407 struct url_actions *b;
2410 init_current_action(csp->action);
2412 for (i = 0; i < MAX_AF_FILES; i++)
2414 if (((fl = csp->actions_list[i]) == NULL) || ((b = fl->f) == NULL))
2419 apply_url_actions(csp->action, http, b);
2426 /*********************************************************************
2428 * Function : apply_url_actions
2430 * Description : Applies a list of URL actions.
2433 * 1 : action = Destination.
2434 * 2 : http = Current URL
2435 * 3 : b = list of URL actions to apply
2439 *********************************************************************/
2440 void apply_url_actions(struct current_action_spec *action,
2441 struct http_request *http,
2442 struct url_actions *b)
2446 /* Should never happen */
2450 for (b = b->next; NULL != b; b = b->next)
2452 if (url_match(b->url, http))
2454 merge_current_action(action, b->action);
2460 /*********************************************************************
2462 * Function : get_forward_override_settings
2464 * Description : Returns forward settings as specified with the
2465 * forward-override{} action. forward-override accepts
2466 * forward lines similar to the one used in the
2467 * configuration file, but without the URL pattern.
2473 * in the configuration file can be replaced with
2474 * the action section:
2476 * {+forward-override{forward .}}
2480 * 1 : csp = Current client state (buffers, headers, etc...)
2482 * Returns : Pointer to forwarding structure in case of success.
2483 * Invalid syntax is fatal.
2485 *********************************************************************/
2486 const static struct forward_spec *get_forward_override_settings(struct client_state *csp)
2488 const char *forward_override_line = csp->action->string[ACTION_STRING_FORWARD_OVERRIDE];
2489 char forward_settings[BUFFER_SIZE];
2490 char *http_parent = NULL;
2491 /* variable names were chosen for consistency reasons. */
2492 struct forward_spec *fwd = NULL;
2496 assert(csp->action->flags & ACTION_FORWARD_OVERRIDE);
2497 /* Should be enforced by load_one_actions_file() */
2498 assert(strlen(forward_override_line) < sizeof(forward_settings) - 1);
2500 /* Create a copy ssplit can modify */
2501 strlcpy(forward_settings, forward_override_line, sizeof(forward_settings));
2503 if (NULL != csp->fwd)
2506 * XXX: Currently necessary to prevent memory
2507 * leaks when the show-url-info cgi page is visited.
2509 unload_forward_spec(csp->fwd);
2513 * allocate a new forward node, valid only for
2514 * the lifetime of this request. Save its location
2515 * in csp as well, so sweep() can free it later on.
2517 fwd = csp->fwd = zalloc(sizeof(*fwd));
2520 log_error(LOG_LEVEL_FATAL,
2521 "can't allocate memory for forward-override{%s}", forward_override_line);
2522 /* Never get here - LOG_LEVEL_FATAL causes program exit */
2525 vec_count = ssplit(forward_settings, " \t", vec, SZ(vec), 1, 1);
2526 if ((vec_count == 2) && !strcasecmp(vec[0], "forward"))
2528 fwd->type = SOCKS_NONE;
2530 /* Parse the parent HTTP proxy host:port */
2531 http_parent = vec[1];
2534 else if (vec_count == 3)
2536 char *socks_proxy = NULL;
2538 if (!strcasecmp(vec[0], "forward-socks4"))
2540 fwd->type = SOCKS_4;
2541 socks_proxy = vec[1];
2543 else if (!strcasecmp(vec[0], "forward-socks4a"))
2545 fwd->type = SOCKS_4A;
2546 socks_proxy = vec[1];
2548 else if (!strcasecmp(vec[0], "forward-socks5"))
2550 fwd->type = SOCKS_5;
2551 socks_proxy = vec[1];
2554 if (NULL != socks_proxy)
2556 /* Parse the SOCKS proxy host[:port] */
2557 fwd->gateway_host = strdup(socks_proxy);
2559 if (NULL != (socks_proxy = strchr(fwd->gateway_host, ':')))
2561 *socks_proxy++ = '\0';
2562 fwd->gateway_port = strtol(socks_proxy, NULL, 0);
2565 if (fwd->gateway_port <= 0)
2567 fwd->gateway_port = 1080;
2570 http_parent = vec[2];
2574 if (NULL == http_parent)
2576 log_error(LOG_LEVEL_FATAL,
2577 "Invalid forward-override syntax in: %s", forward_override_line);
2578 /* Never get here - LOG_LEVEL_FATAL causes program exit */
2581 /* Parse http forwarding settings */
2582 if (strcmp(http_parent, ".") != 0)
2584 fwd->forward_host = strdup(http_parent);
2586 if (NULL != (http_parent = strchr(fwd->forward_host, ':')))
2588 *http_parent++ = '\0';
2589 fwd->forward_port = strtol(http_parent, NULL, 0);
2592 if (fwd->forward_port <= 0)
2594 fwd->forward_port = 8000;
2598 assert (NULL != fwd);
2600 log_error(LOG_LEVEL_CONNECT,
2601 "Overriding forwarding settings based on \'%s\'", forward_override_line);
2607 /*********************************************************************
2609 * Function : forward_url
2611 * Description : Should we forward this to another proxy?
2614 * 1 : csp = Current client state (buffers, headers, etc...)
2615 * 2 : http = http_request request for current URL
2617 * Returns : Pointer to forwarding information.
2619 *********************************************************************/
2620 const struct forward_spec *forward_url(struct client_state *csp,
2621 const struct http_request *http)
2623 static const struct forward_spec fwd_default[1] = { FORWARD_SPEC_INITIALIZER };
2624 struct forward_spec *fwd = csp->config->forward;
2626 if (csp->action->flags & ACTION_FORWARD_OVERRIDE)
2628 return get_forward_override_settings(csp);
2638 if (url_match(fwd->url, http))
2649 /*********************************************************************
2651 * Function : direct_response
2653 * Description : Check if Max-Forwards == 0 for an OPTIONS or TRACE
2654 * request and if so, return a HTTP 501 to the client.
2656 * FIXME: I have a stupid name and I should handle the
2657 * requests properly. Still, what we do here is rfc-
2658 * compliant, whereas ignoring or forwarding are not.
2661 * 1 : csp = Current client state (buffers, headers, etc...)
2663 * Returns : http_response if , NULL if nonmatch or handler fail
2665 *********************************************************************/
2666 struct http_response *direct_response(struct client_state *csp)
2668 struct http_response *rsp;
2669 struct list_entry *p;
2671 if ((0 == strcmpic(csp->http->gpc, "trace"))
2672 || (0 == strcmpic(csp->http->gpc, "options")))
2674 for (p = csp->headers->first; (p != NULL) ; p = p->next)
2676 if (!strncmpic("Max-Forwards:", p->str, 13))
2678 unsigned int max_forwards;
2681 * If it's a Max-Forwards value of zero,
2682 * we have to intercept the request.
2684 if (1 == sscanf(p->str+12, ": %u", &max_forwards) && max_forwards == 0)
2687 * FIXME: We could handle at least TRACE here,
2688 * but that would require a verbatim copy of
2689 * the request which we don't have anymore
2691 log_error(LOG_LEVEL_HEADER,
2692 "Detected header \'%s\' in OPTIONS or TRACE request. Returning 501.",
2695 /* Get mem for response or fail*/
2696 if (NULL == (rsp = alloc_http_response()))
2698 return cgi_error_memory();
2701 if (NULL == (rsp->status = strdup("501 Not Implemented")))
2703 free_http_response(rsp);
2704 return cgi_error_memory();
2708 rsp->reason = RSP_REASON_UNSUPPORTED;
2710 return(finish_http_response(csp, rsp));
2719 /*********************************************************************
2721 * Function : content_filters_enabled
2723 * Description : Checks whether there are any content filters
2724 * enabled for the current request.
2727 * 1 : csp = Current client state (buffers, headers, etc...)
2729 * Returns : TRUE for yes, FALSE otherwise
2731 *********************************************************************/
2732 inline int content_filters_enabled(const struct client_state *csp)
2734 return (((csp->rlist != NULL) &&
2735 (!list_is_empty(csp->action->multi[ACTION_MULTI_FILTER]))) ||
2736 (csp->action->flags & (ACTION_DEANIMATE|ACTION_JPEG_INSPECT)));