1 const char filters_rcs[] = "$Id: filters.c,v 1.64 2006/08/31 10:55:49 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'
15 * Copyright : Written by and Copyright (C) 2001, 2004 the SourceForge
16 * Privoxy team. http://www.privoxy.org/
18 * Based on the Internet Junkbuster originally written
19 * by and Copyright (C) 1997 Anonymous Coders and
20 * Junkbusters Corporation. http://www.junkbusters.com
22 * This program is free software; you can redistribute it
23 * and/or modify it under the terms of the GNU General
24 * Public License as published by the Free Software
25 * Foundation; either version 2 of the License, or (at
26 * your option) any later version.
28 * This program is distributed in the hope that it will
29 * be useful, but WITHOUT ANY WARRANTY; without even the
30 * implied warranty of MERCHANTABILITY or FITNESS FOR A
31 * PARTICULAR PURPOSE. See the GNU General Public
32 * License for more details.
34 * The GNU General Public License should be included with
35 * this file. If not, you can view it at
36 * http://www.gnu.org/copyleft/gpl.html
37 * or write to the Free Software Foundation, Inc., 59
38 * Temple Place - Suite 330, Boston, MA 02111-1307, USA.
42 * Revision 1.64 2006/08/31 10:55:49 fabiankeil
43 * Block requests for untrusted URLs with status
44 * code 403 instead of 200.
46 * Revision 1.63 2006/08/31 10:11:28 fabiankeil
47 * Don't free p which is still in use and will be later
48 * freed by free_map(). Don't claim the referrer is unknown
49 * when the client didn't set one.
51 * Revision 1.62 2006/08/14 00:27:47 david__schmidt
52 * Feature request 595948: Re-Filter logging in single line
54 * Revision 1.61 2006/08/03 02:46:41 david__schmidt
55 * Incorporate Fabian Keil's patch work:
\rhttp://www.fabiankeil.de/sourcecode/privoxy/
57 * Revision 1.60 2006/07/18 14:48:46 david__schmidt
58 * Reorganizing the repository: swapping out what was HEAD (the old 3.1 branch)
59 * with what was really the latest development (the v_3_0_branch branch)
61 * Revision 1.58.2.9 2006/01/29 23:10:56 david__schmidt
62 * Multiple filter file support
64 * Revision 1.58.2.8 2005/05/07 21:50:55 david__schmidt
65 * A few memory leaks plugged (mostly on error paths)
67 * Revision 1.58.2.7 2004/10/03 12:53:32 david__schmidt
68 * Add the ability to check jpeg images for invalid
69 * lengths of comment blocks. Defensive strategy
70 * against the exploit:
71 * Microsoft Security Bulletin MS04-028
72 * Buffer Overrun in JPEG Processing (GDI+) Could
73 * Allow Code Execution (833987)
74 * Enabled with +inspect-jpegs in actions files.
76 * Revision 1.58.2.6 2003/12/06 22:18:27 gliptak
77 * Correcting compile problem with FEATURE_IMAGE_BLOCKING
79 * Revision 1.58.2.5 2003/11/11 13:10:31 oes
80 * Fixed bug #839859: "See why" link URL now gets url-encoded.
82 * Revision 1.58.2.4 2003/02/28 12:52:45 oes
85 * Revision 1.58.2.3 2002/09/25 14:51:51 oes
86 * Added basic support for OPTIONS and TRACE HTTP methods:
87 * New function direct_response which handles OPTIONS and
88 * TRACE requests whose Max-Forwards header field is zero.
90 * Revision 1.58.2.2 2002/08/01 17:18:28 oes
91 * Fixed BR 537651 / SR 579724 (MSIE image detect improper for IE/Mac)
93 * Revision 1.58.2.1 2002/07/26 15:18:53 oes
94 * - Bugfix: Executing a filters without jobs no longer results in
95 * turing off *all* filters.
96 * - Security fix: Malicious web servers can't cause a seg fault
97 * through bogus chunk sizes anymore
99 * Revision 1.58 2002/04/24 02:11:17 oes
100 * Jon's multiple AF patch: url_actions now evaluates rules
103 * Revision 1.57 2002/04/08 20:38:34 swa
106 * Revision 1.56 2002/04/05 15:51:24 oes
107 * - bugfix: error-pages now get correct request protocol
108 * - fix for invalid HTML in trust info
110 * Revision 1.55 2002/04/02 16:13:51 oes
111 * Fix: No "Go there anyway" for SSL
113 * Revision 1.54 2002/04/02 14:55:56 oes
114 * Bugfix: is_untrusted_url() now depends on FEATURE_TRUST, not FEATURE_COOKIE_JAR
116 * Revision 1.53 2002/03/26 22:29:54 swa
117 * we have a new homepage!
119 * Revision 1.52 2002/03/24 16:35:57 jongfoster
122 * Revision 1.51 2002/03/24 15:23:33 jongfoster
125 * Revision 1.50 2002/03/24 13:25:43 swa
126 * name change related issues
128 * Revision 1.49 2002/03/16 20:29:14 oes
131 * Revision 1.48 2002/03/13 20:25:34 oes
132 * Better logging for content filters
134 * Revision 1.47 2002/03/13 00:30:52 jongfoster
136 * Added option of always sending redirect for imageblock,
137 * currently disabled with #if 0.
139 * Revision 1.46 2002/03/12 01:42:49 oes
140 * Introduced modular filters
142 * Revision 1.45 2002/03/08 16:47:50 oes
143 * Added choice beween GIF and PNG built-in images
145 * Revision 1.44 2002/03/07 03:49:31 oes
146 * - Fixed compiler warnings etc
147 * - Changed built-in images from GIF to PNG
148 * (with regard to Unisys patent issue)
149 * - Added a 4x4 pattern PNG which is less intrusive
150 * than the logo but also clearly marks the deleted banners
152 * Revision 1.43 2002/01/22 23:51:59 jongfoster
153 * Replacing strsav() with the safer string_append().
155 * Adding missing html_encode() to error message generators. Where encoded
156 * and unencoded versions of a string were provided, removing the unencoded
159 * Revision 1.42 2002/01/17 21:00:32 jongfoster
160 * Moving all our URL and URL pattern parsing code to urlmatch.c.
162 * Using a single, simple url_match(pattern,url) function - rather than
163 * the 3-line match routine which was repeated all over the place.
165 * Renaming free_url to free_url_spec, since it frees a struct url_spec.
167 * Using parse_http_url() to parse URLs without faking a HTTP
168 * request line for parse_http_request().
170 * Revision 1.41 2001/11/13 00:14:07 jongfoster
171 * Fixing stupid bug now I've figured out what || means.
172 * (It always returns 0 or 1, not one of it's paramaters.)
174 * Revision 1.40 2001/10/26 17:37:55 oes
175 * - Re-enabled Netscape 200/404 bug workaround in block_url():
176 * - Removed OS/2 special case
177 * - Made block_url() independant from sed() having been run
178 * - Made trust_url independant from sed() having been run
179 * - Made is_imageurl independant from sed() having been run.
180 * It now checks User-Agent: and Accept: by itself.
183 * Revision 1.39 2001/10/25 03:40:48 david__schmidt
184 * Change in porting tactics: OS/2's EMX porting layer doesn't allow multiple
185 * threads to call select() simultaneously. So, it's time to do a real, live,
186 * native OS/2 port. See defines for __EMX__ (the porting layer) vs. __OS2__
187 * (native). Both versions will work, but using __OS2__ offers multi-threading.
189 * Revision 1.38 2001/10/23 21:32:33 jongfoster
190 * Adding error-checking to selected functions
192 * Revision 1.37 2001/10/22 15:33:56 david__schmidt
193 * Special-cased OS/2 out of the Netscape-abort-on-404-in-js problem in
194 * filters.c. Added a FIXME in front of the offending code. I'll gladly
195 * put in a better/more robust fix for all parties if one is presented...
196 * It seems that just returning 200 instead of 404 would pretty much fix
197 * it for everyone, but I don't know all the history of the problem.
199 * Revision 1.36 2001/10/10 16:44:16 oes
200 * Added match_portlist function
202 * Revision 1.35 2001/10/07 15:41:23 oes
203 * Replaced 6 boolean members of csp with one bitmap (csp->flags)
205 * New function remove_chunked_transfer_coding that strips chunked
206 * transfer coding to plain and is called by pcrs_filter_response
207 * and gif_deanimate_response if neccessary
209 * Improved handling of zero-change re_filter runs
211 * pcrs_filter_response and gif_deanimate_response now remove
212 * chunked transfer codeing before processing the body.
214 * Revision 1.34 2001/09/20 15:49:36 steudten
216 * Fix BUG: Change int size to size_t size in pcrs_filter_response().
217 * See cgi.c fill_template().
219 * Revision 1.33 2001/09/16 17:05:14 jongfoster
220 * Removing unused #include showarg.h
222 * Revision 1.32 2001/09/16 13:21:27 jongfoster
223 * Changes to use new list functions.
225 * Revision 1.31 2001/09/16 11:38:02 jongfoster
226 * Splitting fill_template() into 2 functions:
227 * template_load() loads the file
228 * template_fill() performs the PCRS regexps.
229 * This is because the CGI edit interface has a "table row"
230 * template which is used many times in the page - this
231 * change means it's only loaded from disk once.
233 * Revision 1.30 2001/09/16 11:00:10 jongfoster
234 * New function alloc_http_response, for symmetry with free_http_response
236 * Revision 1.29 2001/09/13 23:32:40 jongfoster
237 * Moving image data to cgi.c rather than cgi.h
238 * Fixing a GPF under Win32 (and any other OS that protects global
239 * constants from being written to).
241 * Revision 1.28 2001/09/10 10:18:51 oes
242 * Silenced compiler warnings
244 * Revision 1.27 2001/08/05 16:06:20 jongfoster
245 * Modifiying "struct map" so that there are now separate header and
246 * "map_entry" structures. This means that functions which modify a
247 * map no longer need to return a pointer to the modified map.
248 * Also, it no longer reverses the order of the entries (which may be
249 * important with some advanced template substitutions).
251 * Revision 1.26 2001/07/30 22:08:36 jongfoster
252 * Tidying up #defines:
253 * - All feature #defines are now of the form FEATURE_xxx
254 * - Permanently turned off WIN_GUI_EDIT
255 * - Permanently turned on WEBDAV and SPLIT_PROXY_ARGS
257 * Revision 1.25 2001/07/26 10:09:46 oes
258 * Made browser detection a little less naive
260 * Revision 1.24 2001/07/25 17:22:51 oes
261 * Added workaround for Netscape bug that prevents display of page when loading a component fails.
263 * Revision 1.23 2001/07/23 13:40:12 oes
264 * Fixed bug that caused document body to be dropped when pcrs joblist was empty.
266 * Revision 1.22 2001/07/18 12:29:34 oes
267 * - Made gif_deanimate_response respect
268 * csp->action->string[ACTION_STRING_DEANIMATE]
269 * - Logging cosmetics
271 * Revision 1.21 2001/07/13 13:59:53 oes
272 * - Introduced gif_deanimate_response which shares the
273 * generic content modification interface of pcrs_filter_response
274 * and acts as a wrapper to deanimate.c:gif_deanimate()
275 * - Renamed re_process_buffer to pcrs_filter_response
276 * - pcrs_filter_response now returns NULL on failiure
277 * - Removed all #ifdef PCRS
279 * Revision 1.20 2001/07/01 17:01:04 oes
280 * Added comments and missing return statement in is_untrusted_url()
282 * Revision 1.19 2001/06/29 21:45:41 oes
283 * Indentation, CRLF->LF, Tab-> Space
285 * Revision 1.18 2001/06/29 13:27:38 oes
286 * - Cleaned up, renamed and reorderd functions
287 * and improved comments
290 * - Ported to CGI platform. Now delivers
291 * http_response or NULL
292 * - Unified HTML and GIF generation (moved image detection
293 * and GIF generation here from jcc.c:chat())
294 * - Fixed HTTP status to:
295 * - 403 (Forbidden) for the "blocked" HTML message
296 * - 200 (OK) for GIF answers
297 * - 302 (Redirect) for redirect to GIF
300 * - Ported to CGI platform. Now delivers
301 * http_response or NULL
302 * - Separated detection of untrusted URL into
303 * (bool)is_untrusted_url
304 * - Added enforcement of untrusted requests
306 * - Moved redirect_url() from cgi.c to here
307 * and ported it to the CGI platform
309 * - Removed logentry from cancelled commit
311 * Revision 1.17 2001/06/09 10:55:28 jongfoster
312 * Changing BUFSIZ ==> BUFFER_SIZE
314 * Revision 1.16 2001/06/07 23:10:26 jongfoster
315 * Allowing unanchored domain patterns to back off and retry
316 * if they partially match. Optimized right-anchored patterns.
317 * Moving ACL and forward files into config file.
318 * Replacing struct gateway with struct forward_spec
320 * Revision 1.15 2001/06/03 19:12:00 oes
321 * extracted-CGI relevant stuff
323 * Revision 1.14 2001/06/01 10:30:55 oes
324 * Added optional left-anchoring to domaincmp
326 * Revision 1.13 2001/05/31 21:21:30 jongfoster
327 * Permissionsfile / actions file changes:
328 * - Changed "permission" to "action" throughout
329 * - changes to file format to allow string parameters
330 * - Moved helper functions to actions.c
332 * Revision 1.12 2001/05/31 17:35:20 oes
334 * - Enhanced domain part globbing with infix and prefix asterisk
335 * matching and optional unanchored operation
337 * Revision 1.11 2001/05/29 11:53:23 oes
338 * "See why" link added to "blocked" page
340 * Revision 1.10 2001/05/29 09:50:24 jongfoster
341 * Unified blocklist/imagelist/permissionslist.
342 * File format is still under discussion, but the internal changes
345 * Also modified interceptor behaviour:
346 * - We now intercept all URLs beginning with one of the following
347 * prefixes (and *only* these prefixes):
349 * * http://ijbswa.sf.net/config/
350 * * http://ijbswa.sourceforge.net/config/
351 * - New interceptors "home page" - go to http://i.j.b/ to see it.
352 * - Internal changes so that intercepted and fast redirect pages
353 * are not replaced with an image.
354 * - Interceptors now have the option to send a binary page direct
355 * to the client. (i.e. ijb-send-banner uses this)
356 * - Implemented show-url-info interceptor. (Which is why I needed
357 * the above interceptors changes - a typical URL is
358 * "http://i.j.b/show-url-info?url=www.somesite.com/banner.gif".
359 * The previous mechanism would not have intercepted that, and
360 * if it had been intercepted then it then it would have replaced
363 * Revision 1.9 2001/05/27 22:17:04 oes
365 * - re_process_buffer no longer writes the modified buffer
366 * to the client, which was very ugly. It now returns the
367 * buffer, which it is then written by chat.
369 * - content_length now adjusts the Content-Length: header
370 * for modified documents rather than crunch()ing it.
371 * (Length info in csp->content_length, which is 0 for
372 * unmodified documents)
374 * - For this to work, sed() is called twice when filtering.
376 * Revision 1.8 2001/05/26 17:13:28 jongfoster
377 * Filled in a function comment.
379 * Revision 1.7 2001/05/26 15:26:15 jongfoster
380 * ACL feature now provides more security by immediately dropping
381 * connections from untrusted hosts.
383 * Revision 1.6 2001/05/26 00:28:36 jongfoster
384 * Automatic reloading of config file.
385 * Removed obsolete SIGHUP support (Unix) and Reload menu option (Win32).
386 * Most of the global variables have been moved to a new
387 * struct configuration_spec, accessed through csp->config->globalname
388 * Most of the globals remaining are used by the Win32 GUI.
390 * Revision 1.5 2001/05/25 22:34:30 jongfoster
393 * Revision 1.4 2001/05/22 18:46:04 oes
395 * - Enabled filtering banners by size rather than URL
396 * by adding patterns that replace all standard banner
397 * sizes with the "Junkbuster" gif to the re_filterfile
399 * - Enabled filtering WebBugs by providing a pattern
400 * which kills all 1x1 images
402 * - Added support for PCRE_UNGREEDY behaviour to pcrs,
403 * which is selected by the (nonstandard and therefore
404 * capital) letter 'U' in the option string.
405 * It causes the quantifiers to be ungreedy by default.
406 * Appending a ? turns back to greedy (!).
408 * - Added a new interceptor ijb-send-banner, which
409 * sends back the "Junkbuster" gif. Without imagelist or
410 * MSIE detection support, or if tinygif = 1, or the
411 * URL isn't recognized as an imageurl, a lame HTML
412 * explanation is sent instead.
414 * - Added new feature, which permits blocking remote
415 * script redirects and firing back a local redirect
417 * The feature is conditionally compiled, i.e. it
418 * can be disabled with --disable-fast-redirects,
419 * plus it must be activated by a "fast-redirects"
420 * line in the config file, has its own log level
421 * and of course wants to be displayed by show-proxy-args
422 * Note: Boy, all the #ifdefs in 1001 locations and
423 * all the fumbling with configure.in and acconfig.h
424 * were *way* more work than the feature itself :-(
426 * - Because a generic redirect template was needed for
427 * this, tinygif = 3 now uses the same.
429 * - Moved GIFs, and other static HTTP response templates
434 * - Removed some >400 CRs again (Jon, you really worked
437 * Revision 1.3 2001/05/20 16:44:47 jongfoster
438 * Removing last hardcoded Junkbusters.com URLs.
440 * Revision 1.2 2001/05/20 01:21:20 jongfoster
441 * Version 2.9.4 checkin.
442 * - Merged popupfile and cookiefile, and added control over PCRS
443 * filtering, in new "permissionsfile".
444 * - Implemented LOG_LEVEL_FATAL, so that if there is a configuration
445 * file error you now get a message box (in the Win32 GUI) rather
446 * than the program exiting with no explanation.
447 * - Made killpopup use the PCRS MIME-type checking and HTTP-header
449 * - Removed tabs from "config"
450 * - Moved duplicated url parsing code in "loaders.c" to a new funcition.
451 * - Bumped up version number.
453 * Revision 1.1.1.1 2001/05/15 13:58:52 oes
454 * Initial import of version 2.9.3 source tree
457 *********************************************************************/
463 #include <sys/types.h>
472 #endif /* ndef __OS2__ */
473 #include <netinet/in.h>
475 #include <winsock2.h>
476 #endif /* ndef _WIN32 */
480 #endif /* def __OS2__ */
488 #include "jbsockets.h"
489 #include "miscutil.h"
493 #include "deanimate.h"
494 #include "urlmatch.h"
500 const char filters_h_rcs[] = FILTERS_H_VERSION;
502 /* Fix a problem with Solaris. There should be no effect on other
504 * Solaris's isspace() is a macro which uses it's argument directly
505 * as an array index. Therefore we need to make sure that high-bit
506 * characters generate +ve values, and ideally we also want to make
507 * the argument match the declared parameter type of "int".
509 #define ijb_isdigit(__X) isdigit((int)(unsigned char)(__X))
513 /*********************************************************************
515 * Function : block_acl
517 * Description : Block this request?
518 * Decide yes or no based on ACL file.
521 * 1 : dst = The proxy or gateway address this is going to.
522 * Or NULL to check all possible targets.
523 * 2 : csp = Current client state (buffers, headers, etc...)
524 * Also includes the client IP address.
526 * Returns : 0 = FALSE (don't block) and 1 = TRUE (do block)
528 *********************************************************************/
529 int block_acl(struct access_control_addr *dst, struct client_state *csp)
531 struct access_control_list *acl = csp->config->acl;
533 /* if not using an access control list, then permit the connection */
539 /* search the list */
542 if ((csp->ip_addr_long & acl->src->mask) == acl->src->addr)
546 /* Just want to check if they have any access */
547 if (acl->action == ACL_PERMIT)
552 else if ( ((dst->addr & acl->dst->mask) == acl->dst->addr)
553 && ((dst->port == acl->dst->port) || (acl->dst->port == 0)))
555 if (acl->action == ACL_PERMIT)
573 /*********************************************************************
575 * Function : acl_addr
577 * Description : Called from `load_config' to parse an ACL address.
580 * 1 : aspec = String specifying ACL address.
581 * 2 : aca = struct access_control_addr to fill in.
583 * Returns : 0 => Ok, everything else is an error.
585 *********************************************************************/
586 int acl_addr(char *aspec, struct access_control_addr *aca)
588 int i, masklength, port;
594 if ((p = strchr(aspec, '/')) != NULL)
598 if (ijb_isdigit(*p) == 0)
602 masklength = atoi(p);
605 if ((masklength < 0) || (masklength > 32))
610 if ((p = strchr(aspec, ':')) != NULL)
614 if (ijb_isdigit(*p) == 0)
623 aca->addr = ntohl(resolve_hostname_to_ip(aspec));
625 if (aca->addr == INADDR_NONE)
630 /* build the netmask */
632 for (i=1; i <= masklength ; i++)
634 aca->mask |= (1 << (32 - i));
637 /* now mask off the host portion of the ip address
638 * (i.e. save on the network portion of the address).
640 aca->addr = aca->addr & aca->mask;
645 #endif /* def FEATURE_ACL */
648 /*********************************************************************
650 * Function : match_portlist
652 * Description : Check if a given number is covered by a comma
653 * separated list of numbers and ranges (a,b-c,d,..)
656 * 1 : portlist = String with list
657 * 2 : port = port to check
659 * Returns : 0 => no match
662 *********************************************************************/
663 int match_portlist(const char *portlist, int port)
665 char *min, *max, *next, *portlist_copy;
667 min = next = portlist_copy = strdup(portlist);
670 * Zero-terminate first item and remember offset for next
672 if (NULL != (next = strchr(portlist_copy, (int) ',')))
678 * Loop through all items, checking for match
682 if (NULL == (max = strchr(min, (int) '-')))
685 * No dash, check for equality
687 if (port == atoi(min))
696 * This is a range, so check if between min and max,
697 * or, if max was omitted, between min and 65K
700 if(port >= atoi(min) && port <= (atoi(max) ? atoi(max) : 65535))
714 * Zero-terminate next item and remember offset for n+1
716 if ((NULL != next) && (NULL != (next = strchr(next, (int) ','))))
728 /*********************************************************************
730 * Function : block_url
732 * Description : Called from `chat'. Check to see if we need to block this.
735 * 1 : csp = Current client state (buffers, headers, etc...)
737 * Returns : NULL => unblocked, else HTTP block response
739 *********************************************************************/
740 struct http_response *block_url(struct client_state *csp)
742 struct http_response *rsp;
743 const char *new_content_type = NULL;
746 * If it's not blocked, don't block it ;-)
748 if ((csp->action->flags & ACTION_BLOCK) == 0)
752 if (csp->action->flags & ACTION_REDIRECT)
754 log_error(LOG_LEVEL_ERROR, "redirect{} overruled by block.");
757 * Else, prepare a response
759 if (NULL == (rsp = alloc_http_response()))
761 return cgi_error_memory();
765 * If it's an image-url, send back an image or redirect
766 * as specified by the relevant +image action
768 #ifdef FEATURE_IMAGE_BLOCKING
769 if (((csp->action->flags & ACTION_IMAGE_BLOCKER) != 0)
773 /* determine HOW images should be blocked */
774 p = csp->action->string[ACTION_STRING_IMAGE_BLOCKER];
776 if(csp->action->flags & ACTION_HANDLE_AS_EMPTY_DOCUMENT)
778 log_error(LOG_LEVEL_ERROR, "handle-as-empty-document overruled by handle-as-image.");
780 #if 1 /* Two alternative strategies, use this one for now: */
782 /* and handle accordingly: */
783 if ((p == NULL) || (0 == strcmpic(p, "pattern")))
785 rsp->status = strdup("403 Request blocked by Privoxy");
786 if (rsp->status == NULL)
788 free_http_response(rsp);
789 return cgi_error_memory();
791 rsp->body = bindup(image_pattern_data, image_pattern_length);
792 if (rsp->body == NULL)
794 free_http_response(rsp);
795 return cgi_error_memory();
797 rsp->content_length = image_pattern_length;
799 if (enlist_unique_header(rsp->headers, "Content-Type", BUILTIN_IMAGE_MIMETYPE))
801 free_http_response(rsp);
802 return cgi_error_memory();
806 else if (0 == strcmpic(p, "blank"))
808 rsp->status = strdup("403 Request blocked by Privoxy");
809 if (rsp->status == NULL)
811 free_http_response(rsp);
812 return cgi_error_memory();
814 rsp->body = bindup(image_blank_data, image_blank_length);
815 if (rsp->body == NULL)
817 free_http_response(rsp);
818 return cgi_error_memory();
820 rsp->content_length = image_blank_length;
822 if (enlist_unique_header(rsp->headers, "Content-Type", BUILTIN_IMAGE_MIMETYPE))
824 free_http_response(rsp);
825 return cgi_error_memory();
831 rsp->status = strdup("302 Local Redirect from Privoxy");
832 if (rsp->status == NULL)
834 free_http_response(rsp);
835 return cgi_error_memory();
838 if (enlist_unique_header(rsp->headers, "Location", p))
840 free_http_response(rsp);
841 return cgi_error_memory();
845 #else /* Following code is disabled for now */
847 /* and handle accordingly: */
848 if ((p == NULL) || (0 == strcmpic(p, "pattern")))
850 p = CGI_PREFIX "send-banner?type=pattern";
852 else if (0 == strcmpic(p, "blank"))
854 p = CGI_PREFIX "send-banner?type=blank";
856 rsp->status = strdup("302 Local Redirect from Privoxy");
857 if (rsp->status == NULL)
859 free_http_response(rsp);
860 return cgi_error_memory();
863 if (enlist_unique_header(rsp->headers, "Location", p))
865 free_http_response(rsp);
866 return cgi_error_memory();
868 #endif /* Preceeding code is disabled for now */
870 else if(csp->action->flags & ACTION_HANDLE_AS_EMPTY_DOCUMENT)
873 * Send empty document.
875 new_content_type = csp->action->string[ACTION_STRING_CONTENT_TYPE];
878 rsp->body = strdup(" ");
879 rsp->content_length = 1;
881 rsp->status = strdup("403 Request blocked by Privoxy");
882 if (rsp->status == NULL)
884 free_http_response(rsp);
885 return cgi_error_memory();
887 if (new_content_type != 0)
889 log_error(LOG_LEVEL_HEADER, "Overwriting Content-Type with %s", new_content_type);
890 if (enlist_unique_header(rsp->headers, "Content-Type", new_content_type))
892 free_http_response(rsp);
893 return cgi_error_memory();
899 #endif /* def FEATURE_IMAGE_BLOCKING */
902 * Else, generate an HTML "blocked" message:
906 struct map * exports;
910 * Workaround for stupid Netscape bug which prevents
911 * pages from being displayed if loading a referenced
912 * JavaScript or style sheet fails. So make it appear
913 * as if it succeeded.
915 if ( NULL != (p = get_header_value(csp->headers, "User-Agent:"))
916 && !strncmpic(p, "mozilla", 7) /* Catch Netscape but */
917 && !strstr(p, "Gecko") /* save Mozilla, */
918 && !strstr(p, "compatible") /* MSIE */
919 && !strstr(p, "Opera")) /* and Opera. */
921 rsp->status = strdup("200 Request for blocked URL");
925 rsp->status = strdup("404 Request for blocked URL");
928 if (rsp->status == NULL)
930 free_http_response(rsp);
931 return cgi_error_memory();
934 exports = default_exports(csp, NULL);
937 free_http_response(rsp);
938 return cgi_error_memory();
941 #ifdef FEATURE_FORCE_LOAD
942 err = map(exports, "force-prefix", 1, FORCE_PREFIX, 1);
943 if (csp->http->ssl != 0)
944 #endif /* ndef FEATURE_FORCE_LOAD */
946 err = map_block_killer(exports, "force-support");
949 if (!err) err = map(exports, "protocol", 1, csp->http->ssl ? "https://" : "http://", 1);
950 if (!err) err = map(exports, "hostport", 1, html_encode(csp->http->hostport), 0);
951 if (!err) err = map(exports, "path", 1, html_encode(csp->http->path), 0);
952 if (!err) err = map(exports, "path-ue", 1, url_encode(csp->http->path), 0);
957 free_http_response(rsp);
958 return cgi_error_memory();
961 err = template_fill_for_cgi(csp, "blocked", exports, rsp);
964 free_http_response(rsp);
965 return cgi_error_memory();
969 return finish_http_response(rsp);
975 /*********************************************************************
977 * Function : trust_url FIXME: I should be called distrust_url
979 * Description : Calls is_untrusted_url to determine if the URL is trusted
980 * and if not, returns a HTTP 403 response with a reject message.
983 * 1 : csp = Current client state (buffers, headers, etc...)
985 * Returns : NULL => trusted, else http_response.
987 *********************************************************************/
988 struct http_response *trust_url(struct client_state *csp)
990 struct http_response *rsp;
991 struct map * exports;
992 char buf[BUFFER_SIZE];
994 struct url_spec **tl;
999 * Don't bother to work on trusted URLs
1001 if (!is_untrusted_url(csp))
1007 * Else, prepare a response:
1009 if (NULL == (rsp = alloc_http_response()))
1011 return cgi_error_memory();
1014 rsp->status = strdup("403 Request blocked by Privoxy");
1015 exports = default_exports(csp, NULL);
1016 if (exports == NULL || rsp->status == NULL)
1018 free_http_response(rsp);
1019 return cgi_error_memory();
1023 * Export the protocol, host, port, and referrer information
1025 err = map(exports, "hostport", 1, csp->http->hostport, 1);
1026 if (!err) err = map(exports, "protocol", 1, csp->http->ssl ? "https://" : "http://", 1);
1027 if (!err) err = map(exports, "path", 1, csp->http->path, 1);
1029 if (NULL != (p = get_header_value(csp->headers, "Referer:")))
1031 if (!err) err = map(exports, "referrer", 1, html_encode(p), 0);
1035 if (!err) err = map(exports, "referrer", 1, "none set", 1);
1041 free_http_response(rsp);
1042 return cgi_error_memory();
1046 * Export the trust list
1049 for (tl = csp->config->trust_list; (t = *tl) != NULL ; tl++)
1051 sprintf(buf, "<li>%s</li>\n", t->spec);
1052 string_append(&p, buf);
1054 err = map(exports, "trusted-referrers", 1, p, 0);
1059 free_http_response(rsp);
1060 return cgi_error_memory();
1064 * Export the trust info, if available
1066 if (csp->config->trust_info->first)
1068 struct list_entry *l;
1071 for (l = csp->config->trust_info->first; l ; l = l->next)
1073 sprintf(buf, "<li> <a href=\"%s\">%s</a><br>\n",l->str, l->str);
1074 string_append(&p, buf);
1076 err = map(exports, "trust-info", 1, p, 0);
1080 err = map_block_killer(exports, "have-trust-info");
1086 free_http_response(rsp);
1087 return cgi_error_memory();
1091 * Export the force prefix or the force conditional block killer
1093 #ifdef FEATURE_FORCE_LOAD
1094 err = map(exports, "force-prefix", 1, FORCE_PREFIX, 1);
1095 #else /* ifndef FEATURE_FORCE_LOAD */
1096 err = map_block_killer(exports, "force-support");
1097 #endif /* ndef FEATURE_FORCE_LOAD */
1102 free_http_response(rsp);
1103 return cgi_error_memory();
1107 * Build the response
1109 err = template_fill_for_cgi(csp, "untrusted", exports, rsp);
1112 free_http_response(rsp);
1113 return cgi_error_memory();
1116 return finish_http_response(rsp);
1118 #endif /* def FEATURE_TRUST */
1121 #ifdef FEATURE_FAST_REDIRECTS
1122 /*********************************************************************
1124 * Function : redirect_url
1126 * Description : Checks for redirection URLs and returns a HTTP redirect
1127 * to the destination URL, if necessary
1130 * 1 : csp = Current client state (buffers, headers, etc...)
1132 * Returns : NULL if URL was clean, HTTP redirect otherwise.
1134 *********************************************************************/
1135 struct http_response *redirect_url(struct client_state *csp)
1138 struct http_response *rsp;
1139 char *redirect_mode = NULL;
1142 if ((csp->action->flags & ACTION_REDIRECT))
1144 q = csp->action->string[ACTION_STRING_REDIRECT];
1146 else if ((csp->action->flags & ACTION_FAST_REDIRECTS))
1148 redirect_mode = csp->action->string[ACTION_STRING_FAST_REDIRECTS];
1149 if (0 == strcmpic(redirect_mode, "check-decoded-url"))
1151 p = q = csp->http->path;
1152 log_error(LOG_LEVEL_REDIRECTS, "Decoding path: %s if necessary.", p);
1155 if (*p == '%') /* Escape sequence? */
1157 /* Yes, translate from hexadecimal to decimal */
1171 /* No, forward character. */
1177 p = q = csp->http->path;
1178 log_error(LOG_LEVEL_REDIRECTS, "Checking path for redirects: %s", p);
1181 * find the last URL encoded in the request
1183 while ((p = strstr(p, "http://")) != NULL)
1190 /* All redirection actions are disabled */
1194 * if there was any, generate and return a HTTP redirect
1196 if (q != csp->http->path)
1198 log_error(LOG_LEVEL_REDIRECTS, "redirecting to: %s", q);
1200 if (NULL == (rsp = alloc_http_response()))
1202 return cgi_error_memory();
1205 if ( enlist_unique_header(rsp->headers, "Location", q)
1206 || (NULL == (rsp->status = strdup("302 Local Redirect from Privoxy"))) )
1208 free_http_response(rsp);
1209 return cgi_error_memory();
1212 return finish_http_response(rsp);
1220 #endif /* def FEATURE_FAST_REDIRECTS */
1223 #ifdef FEATURE_IMAGE_BLOCKING
1224 /*********************************************************************
1226 * Function : is_imageurl
1228 * Description : Given a URL, decide whether it is an image or not,
1229 * using either the info from a previous +image action
1230 * or, #ifdef FEATURE_IMAGE_DETECT_MSIE, and the browser
1231 * is MSIE and not on a Mac, tell from the browser's accept
1235 * 1 : csp = Current client state (buffers, headers, etc...)
1237 * Returns : True (nonzero) if URL is an image, false (0)
1240 *********************************************************************/
1241 int is_imageurl(struct client_state *csp)
1243 #ifdef FEATURE_IMAGE_DETECT_MSIE
1246 tmp = get_header_value(csp->headers, "User-Agent:");
1247 if (tmp && strstr(tmp, "MSIE") && !strstr(tmp, "Mac_"))
1249 tmp = get_header_value(csp->headers, "Accept:");
1250 if (tmp && strstr(tmp, "image/gif"))
1252 /* Client will accept HTML. If this seems counterintuitive,
1262 #endif /* def FEATURE_IMAGE_DETECT_MSIE */
1264 return ((csp->action->flags & ACTION_IMAGE) != 0);
1267 #endif /* def FEATURE_IMAGE_BLOCKING */
1270 #ifdef FEATURE_TRUST
1271 /*********************************************************************
1273 * Function : is_untrusted_url
1275 * Description : Should we "distrust" this URL (and block it)?
1277 * Yes if it matches a line in the trustfile, or if the
1278 * referrer matches a line starting with "+" in the
1283 * 1 : csp = Current client state (buffers, headers, etc...)
1285 * Returns : 0 => trusted, 1 => untrusted
1287 *********************************************************************/
1288 int is_untrusted_url(struct client_state *csp)
1290 struct file_list *fl;
1291 struct block_spec *b;
1292 struct url_spec **trusted_url;
1293 struct http_request rhttp[1];
1294 const char * referer;
1298 * If we don't have a trustlist, we trust everybody
1300 if (((fl = csp->tlist) == NULL) || ((b = fl->f) == NULL))
1305 memset(rhttp, '\0', sizeof(*rhttp));
1308 * Do we trust the request URL itself?
1310 for (b = b->next; b ; b = b->next)
1312 if (url_match(b->url, csp->http))
1318 if (NULL == (referer = get_header_value(csp->headers, "Referer:")))
1320 /* no referrer was supplied */
1326 * If not, do we maybe trust its referrer?
1328 err = parse_http_url(referer, rhttp, csp);
1334 for (trusted_url = csp->config->trust_list; *trusted_url != NULL; trusted_url++)
1336 if (url_match(*trusted_url, rhttp))
1338 /* if the URL's referrer is from a trusted referrer, then
1339 * add the target spec to the trustfile as an unblocked
1340 * domain and return NULL (which means it's OK).
1345 if (NULL != (fp = fopen(csp->config->trustfile, "a")))
1349 char * new_entry = strdup("~");
1351 string_append(&new_entry, csp->http->hostport);
1353 path = csp->http->path;
1354 if ( (path[0] == '/')
1356 && ((path_end = strchr(path + 2, '/')) != NULL))
1358 /* since this path points into a user's home space
1359 * be sure to include this spec in the trustfile.
1361 int path_len = path_end - path; /* save offset */
1362 path = strdup(path); /* Copy string */
1365 path_end = path + path_len; /* regenerate ptr to new buffer */
1366 *(path_end + 1) = '\0'; /* Truncate path after '/' */
1368 string_join(&new_entry, path);
1371 if (new_entry != NULL)
1373 fprintf(fp, "%s\n", new_entry);
1378 /* FIXME: No way to handle out-of memory, so mostly ignoring it */
1379 log_error(LOG_LEVEL_ERROR, "Out of memory adding pattern to trust file");
1389 #endif /* def FEATURE_TRUST */
1392 /*********************************************************************
1394 * Function : pcrs_filter_response
1396 * Description : Execute all text substitutions from all applying
1397 * +filter actions on the text buffer that's been accumulated
1398 * in csp->iob->buf. If this changes the contents, set
1399 * csp->content_length to the modified size and raise the
1400 * CSP_FLAG_MODIFIED flag.
1403 * 1 : csp = Current client state (buffers, headers, etc...)
1405 * Returns : a pointer to the (newly allocated) modified buffer.
1406 * or NULL if there were no hits or something went wrong
1408 *********************************************************************/
1409 char *pcrs_filter_response(struct client_state *csp)
1412 size_t size, prev_size;
1414 char *old = csp->iob->cur, *new = NULL;
1417 struct file_list *fl;
1418 struct re_filterfile_spec *b;
1419 struct list_entry *filtername;
1421 int i, found_filters = 0;
1426 if (csp->iob->cur >= csp->iob->eod)
1430 size = csp->iob->eod - csp->iob->cur;
1433 * Need to check the set of re_filterfiles...
1435 for (i = 0; i < MAX_AF_FILES; i++)
1448 if (0 == found_filters)
1450 log_error(LOG_LEVEL_ERROR, "Unable to get current state of regexp filtering.");
1455 * If the body has a "chunked" transfer-encoding,
1456 * get rid of it first, adjusting size and iob->eod
1458 if (csp->flags & CSP_FLAG_CHUNKED)
1460 log_error(LOG_LEVEL_RE_FILTER, "Need to de-chunk first");
1461 if (0 == (size = remove_chunked_transfer_coding(csp->iob->cur, size)))
1465 csp->iob->eod = csp->iob->cur + size;
1466 csp->flags |= CSP_FLAG_MODIFIED;
1469 for (i = 0; i < MAX_AF_FILES; i++)
1472 if ((NULL == fl) || (NULL == fl->f))
1475 * For all applying +filter actions, look if a filter by that
1476 * name exists and if yes, execute it's pcrs_joblist on the
1479 for (b = fl->f; b; b = b->next)
1481 for (filtername = csp->action->multi[ACTION_MULTI_FILTER]->first;
1482 filtername ; filtername = filtername->next)
1484 if (strcmp(b->name, filtername->str) == 0)
1486 int current_hits = 0;
1488 if ( NULL == b->joblist )
1490 log_error(LOG_LEVEL_RE_FILTER, "Filter %s has empty joblist. Nothing to do.", b->name);
1495 /* Apply all jobs from the joblist */
1496 for (job = b->joblist; NULL != job; job = job->next)
1498 current_hits += pcrs_execute(job, old, size, &new, &size);
1499 if (old != csp->iob->cur) free(old);
1503 log_error(LOG_LEVEL_RE_FILTER, "re_filtering %s%s (size %d) with filter %s produced %d hits (new size %d).",
1504 csp->http->hostport, csp->http->path, prev_size, b->name, current_hits, size);
1506 hits += current_hits;
1513 * If there were no hits, destroy our copy and let
1514 * chat() use the original in csp->iob
1522 csp->flags |= CSP_FLAG_MODIFIED;
1523 csp->content_length = size;
1531 /*********************************************************************
1533 * Function : gif_deanimate_response
1535 * Description : Deanimate the GIF image that has been accumulated in
1536 * csp->iob->buf, set csp->content_length to the modified
1537 * size and raise the CSP_FLAG_MODIFIED flag.
1540 * 1 : csp = Current client state (buffers, headers, etc...)
1542 * Returns : a pointer to the (newly allocated) modified buffer.
1543 * or NULL in case something went wrong.
1545 *********************************************************************/
1546 char *gif_deanimate_response(struct client_state *csp)
1548 struct binbuffer *in, *out;
1550 size_t size = csp->iob->eod - csp->iob->cur;
1553 * If the body has a "chunked" transfer-encoding,
1554 * get rid of it first, adjusting size and iob->eod
1556 if (csp->flags & CSP_FLAG_CHUNKED)
1558 log_error(LOG_LEVEL_DEANIMATE, "Need to de-chunk first");
1559 if (0 == (size = remove_chunked_transfer_coding(csp->iob->cur, size)))
1563 csp->iob->eod = csp->iob->cur + size;
1564 csp->flags |= CSP_FLAG_MODIFIED;
1567 if ( (NULL == (in = (struct binbuffer *)zalloc(sizeof *in )))
1568 || (NULL == (out = (struct binbuffer *)zalloc(sizeof *out))) )
1570 log_error(LOG_LEVEL_DEANIMATE, "failed! (no mem)");
1574 in->buffer = csp->iob->cur;
1577 if (gif_deanimate(in, out, strncmp("last", csp->action->string[ACTION_STRING_DEANIMATE], 4)))
1579 log_error(LOG_LEVEL_DEANIMATE, "failed! (gif parsing)");
1586 if ((int)size == out->offset)
1588 log_error(LOG_LEVEL_DEANIMATE, "GIF not changed.");
1592 log_error(LOG_LEVEL_DEANIMATE, "Success! GIF shrunk from %d bytes to %d.", size, out->offset);
1594 csp->content_length = out->offset;
1595 csp->flags |= CSP_FLAG_MODIFIED;
1605 /*********************************************************************
1607 * Function : jpeg_inspect_response
1612 * 1 : csp = Current client state (buffers, headers, etc...)
1614 * Returns : a pointer to the (newly allocated) modified buffer
1615 * or NULL in case something went wrong.
1617 *********************************************************************/
1618 char *jpeg_inspect_response(struct client_state *csp)
1620 struct binbuffer *in = NULL, *out = NULL;
1622 size_t size = csp->iob->eod - csp->iob->cur;
1625 * If the body has a "chunked" transfer-encoding,
1626 * get rid of it first, adjusting size and iob->eod
1628 if (csp->flags & CSP_FLAG_CHUNKED)
1630 log_error(LOG_LEVEL_DEANIMATE, "Need to de-chunk first");
1631 if (0 == (size = remove_chunked_transfer_coding(csp->iob->cur, size)))
1635 csp->iob->eod = csp->iob->cur + size;
1636 csp->flags |= CSP_FLAG_MODIFIED;
1639 if (NULL == (in = (struct binbuffer *)zalloc(sizeof *in )))
1641 log_error(LOG_LEVEL_DEANIMATE, "failed! (jpeg no mem 1)");
1645 if (NULL == (out = (struct binbuffer *)zalloc(sizeof *out)))
1647 log_error(LOG_LEVEL_DEANIMATE, "failed! (jpeg no mem 2)");
1651 in->buffer = csp->iob->cur;
1655 * Calling jpeg_inspect has the side-effect of creating and
1656 * modifying the image buffer of "out" directly.
1658 if (jpeg_inspect(in, out))
1660 log_error(LOG_LEVEL_DEANIMATE, "failed! (jpeg parsing)");
1668 csp->content_length = out->offset;
1669 csp->flags |= CSP_FLAG_MODIFIED;
1679 /*********************************************************************
1681 * Function : remove_chunked_transfer_coding
1683 * Description : In-situ remove the "chunked" transfer coding as defined
1684 * in rfc2616 from a buffer.
1687 * 1 : buffer = Pointer to the text buffer
1688 * 2 : size = Number of bytes to be processed
1690 * Returns : The new size, i.e. the number of bytes from buffer which
1691 * are occupied by the stripped body, or 0 in case something
1694 *********************************************************************/
1695 int remove_chunked_transfer_coding(char *buffer, const size_t size)
1698 unsigned int chunksize = 0;
1699 char *from_p, *to_p;
1702 from_p = to_p = buffer;
1704 if (sscanf(buffer, "%x", &chunksize) != 1)
1706 log_error(LOG_LEVEL_ERROR, "Invalid first chunksize while stripping \"chunked\" transfer coding");
1710 while (chunksize > 0)
1712 if (NULL == (from_p = strstr(from_p, "\r\n")))
1714 log_error(LOG_LEVEL_ERROR, "Parse error while stripping \"chunked\" transfer coding");
1718 if ((newsize += chunksize) >= size)
1720 log_error(LOG_LEVEL_ERROR, "Chunksize exceeds buffer in \"chunked\" transfer coding");
1725 memmove(to_p, from_p, (size_t) chunksize);
1726 to_p = buffer + newsize;
1727 from_p += chunksize + 2;
1729 if (sscanf(from_p, "%x", &chunksize) != 1)
1731 log_error(LOG_LEVEL_ERROR, "Parse error while stripping \"chunked\" transfer coding");
1736 /* FIXME: Should this get its own loglevel? */
1737 log_error(LOG_LEVEL_RE_FILTER, "De-chunking successful. Shrunk from %d to %d\n", size, newsize);
1743 /*********************************************************************
1745 * Function : url_actions
1747 * Description : Gets the actions for this URL.
1750 * 1 : http = http_request request for blocked URLs
1751 * 2 : csp = Current client state (buffers, headers, etc...)
1755 *********************************************************************/
1756 void url_actions(struct http_request *http,
1757 struct client_state *csp)
1759 struct file_list *fl;
1760 struct url_actions *b;
1763 init_current_action(csp->action);
1765 for (i = 0; i < MAX_AF_FILES; i++)
1767 if (((fl = csp->actions_list[i]) == NULL) || ((b = fl->f) == NULL))
1772 apply_url_actions(csp->action, http, b);
1779 /*********************************************************************
1781 * Function : apply_url_actions
1783 * Description : Applies a list of URL actions.
1786 * 1 : action = Destination.
1787 * 2 : http = Current URL
1788 * 3 : b = list of URL actions to apply
1792 *********************************************************************/
1793 void apply_url_actions(struct current_action_spec *action,
1794 struct http_request *http,
1795 struct url_actions *b)
1799 /* Should never happen */
1803 for (b = b->next; NULL != b; b = b->next)
1805 if (url_match(b->url, http))
1807 merge_current_action(action, b->action);
1813 /*********************************************************************
1815 * Function : forward_url
1817 * Description : Should we forward this to another proxy?
1820 * 1 : http = http_request request for current URL
1821 * 2 : csp = Current client state (buffers, headers, etc...)
1823 * Returns : Pointer to forwarding information.
1825 *********************************************************************/
1826 const struct forward_spec * forward_url(struct http_request *http,
1827 struct client_state *csp)
1829 static const struct forward_spec fwd_default[1] = { FORWARD_SPEC_INITIALIZER };
1830 struct forward_spec *fwd = csp->config->forward;
1839 if (url_match(fwd->url, http))
1850 /*********************************************************************
1852 * Function : direct_response
1854 * Description : Check if Max-Forwards == 0 for an OPTIONS or TRACE
1855 * request and if so, return a HTTP 501 to the client.
1857 * FIXME: I have a stupid name and I should handle the
1858 * requests properly. Still, what we do here is rfc-
1859 * compliant, whereas ignoring or forwarding are not.
1862 * 1 : csp = Current client state (buffers, headers, etc...)
1864 * Returns : http_response if , NULL if nonmatch or handler fail
1866 *********************************************************************/
1867 struct http_response *direct_response(struct client_state *csp)
1869 struct http_response *rsp;
1870 struct list_entry *p;
1872 if ((0 == strcmpic(csp->http->gpc, "trace"))
1873 || (0 == strcmpic(csp->http->gpc, "options")))
1875 for (p = csp->headers->first; (p != NULL) ; p = p->next)
1877 if (!strncmp("Max-Forwards:", p->str, 13)
1878 && (*(p->str+13) != '\0') && (atoi(p->str+13) == 0))
1880 /* FIXME: We could handle at least TRACE here,
1881 but that would require a verbatim copy of
1882 the request which we don't have anymore */
1884 log_error(LOG_LEVEL_HEADER, "Found Max-Forwards:0 in OPTIONS or TRACE request -- Returning 501");
1886 /* Get mem for response or fail*/
1887 if (NULL == (rsp = alloc_http_response()))
1889 return cgi_error_memory();
1892 if (NULL == (rsp->status = strdup("501 Not Implemented")))
1894 free_http_response(rsp);
1895 return cgi_error_memory();
1899 return(finish_http_response(rsp));