1 #ifndef FILTERS_H_INCLUDED
2 #define FILTERS_H_INCLUDED
3 #define FILTERS_H_VERSION "$Id: filters.h,v 1.22 2006/07/18 14:48:46 david__schmidt Exp $"
4 /*********************************************************************
6 * File : $Source: /cvsroot/ijbswa/current/filters.h,v $
8 * Purpose : Declares functions to parse/crunch headers and pages.
9 * Functions declared include:
10 * `acl_addr', `add_stats', `block_acl', `block_imageurl',
11 * `block_url', `url_actions', `filter_popups', `forward_url'
12 * `ij_untrusted_url', `intercept_url', `re_process_buffer',
13 * `show_proxy_args', and `trust_url'
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 1.22 2006/07/18 14:48:46 david__schmidt
43 * Reorganizing the repository: swapping out what was HEAD (the old 3.1 branch)
44 * with what was really the latest development (the v_3_0_branch branch)
46 * Revision 1.20.2.2 2004/10/03 12:53:32 david__schmidt
47 * Add the ability to check jpeg images for invalid
48 * lengths of comment blocks. Defensive strategy
49 * against the exploit:
50 * Microsoft Security Bulletin MS04-028
51 * Buffer Overrun in JPEG Processing (GDI+) Could
52 * Allow Code Execution (833987)
53 * Enabled with +inspect-jpegs in actions files.
55 * Revision 1.20.2.1 2002/09/25 14:51:51 oes
56 * Added basic support for OPTIONS and TRACE HTTP methods:
57 * New function direct_response which handles OPTIONS and
58 * TRACE requests whose Max-Forwards header field is zero.
60 * Revision 1.20 2002/04/02 14:56:16 oes
61 * Bugfix: is_untrusted_url() and trust_url() now depend on FEATURE_TRUST, not FEATURE_COOKIE_JAR
63 * Revision 1.19 2002/03/26 22:29:54 swa
64 * we have a new homepage!
66 * Revision 1.18 2002/03/25 22:12:45 oes
67 * Added fix for undefined INADDR_NONE on Solaris by Bart Schelstraete
69 * Revision 1.17 2002/03/24 13:25:43 swa
70 * name change related issues
72 * Revision 1.16 2002/01/17 21:01:02 jongfoster
73 * Moving all our URL and URL pattern parsing code to urlmatch.c.
75 * Revision 1.15 2001/10/10 16:44:16 oes
76 * Added match_portlist function
78 * Revision 1.14 2001/10/07 15:41:40 oes
79 * Added prototype for remove_chunked_transfer_coding
81 * Revision 1.13 2001/07/30 22:08:36 jongfoster
82 * Tidying up #defines:
83 * - All feature #defines are now of the form FEATURE_xxx
84 * - Permanently turned off WIN_GUI_EDIT
85 * - Permanently turned on WEBDAV and SPLIT_PROXY_ARGS
87 * Revision 1.12 2001/07/29 19:01:11 jongfoster
88 * Changed _FILENAME_H to FILENAME_H_INCLUDED.
89 * Added forward declarations for needed structures.
91 * Revision 1.11 2001/07/13 14:00:18 oes
92 * - Introduced gif_deanimate_response
93 * - Renamed re_process_buffer to pcrs_filter_response
94 * - Removed all #ifdef PCRS
96 * Revision 1.10 2001/06/29 13:29:01 oes
97 * Cleaned up and updated to reflect the changesin
100 * Revision 1.9 2001/06/07 23:10:53 jongfoster
101 * Replacing struct gateway with struct forward_spec
103 * Revision 1.8 2001/06/03 19:12:00 oes
104 * extracted-CGI relevant stuff
106 * Revision 1.7 2001/05/31 21:21:30 jongfoster
107 * Permissionsfile / actions file changes:
108 * - Changed "permission" to "action" throughout
109 * - changes to file format to allow string parameters
110 * - Moved helper functions to actions.c
112 * Revision 1.6 2001/05/29 09:50:24 jongfoster
113 * Unified blocklist/imagelist/permissionslist.
114 * File format is still under discussion, but the internal changes
117 * Also modified interceptor behaviour:
118 * - We now intercept all URLs beginning with one of the following
119 * prefixes (and *only* these prefixes):
121 * * http://ijbswa.sf.net/config/
122 * * http://ijbswa.sourceforge.net/config/
123 * - New interceptors "home page" - go to http://i.j.b/ to see it.
124 * - Internal changes so that intercepted and fast redirect pages
125 * are not replaced with an image.
126 * - Interceptors now have the option to send a binary page direct
127 * to the client. (i.e. ijb-send-banner uses this)
128 * - Implemented show-url-info interceptor. (Which is why I needed
129 * the above interceptors changes - a typical URL is
130 * "http://i.j.b/show-url-info?url=www.somesite.com/banner.gif".
131 * The previous mechanism would not have intercepted that, and
132 * if it had been intercepted then it then it would have replaced
135 * Revision 1.5 2001/05/27 22:17:04 oes
137 * - re_process_buffer no longer writes the modified buffer
138 * to the client, which was very ugly. It now returns the
139 * buffer, which it is then written by chat.
141 * - content_length now adjusts the Content-Length: header
142 * for modified documents rather than crunch()ing it.
143 * (Length info in csp->content_length, which is 0 for
144 * unmodified documents)
146 * - For this to work, sed() is called twice when filtering.
148 * Revision 1.4 2001/05/26 15:26:15 jongfoster
149 * ACL feature now provides more security by immediately dropping
150 * connections from untrusted hosts.
152 * Revision 1.3 2001/05/22 18:46:04 oes
154 * - Enabled filtering banners by size rather than URL
155 * by adding patterns that replace all standard banner
156 * sizes with the "Junkbuster" gif to the re_filterfile
158 * - Enabled filtering WebBugs by providing a pattern
159 * which kills all 1x1 images
161 * - Added support for PCRE_UNGREEDY behaviour to pcrs,
162 * which is selected by the (nonstandard and therefore
163 * capital) letter 'U' in the option string.
164 * It causes the quantifiers to be ungreedy by default.
165 * Appending a ? turns back to greedy (!).
167 * - Added a new interceptor ijb-send-banner, which
168 * sends back the "Junkbuster" gif. Without imagelist or
169 * MSIE detection support, or if tinygif = 1, or the
170 * URL isn't recognized as an imageurl, a lame HTML
171 * explanation is sent instead.
173 * - Added new feature, which permits blocking remote
174 * script redirects and firing back a local redirect
176 * The feature is conditionally compiled, i.e. it
177 * can be disabled with --disable-fast-redirects,
178 * plus it must be activated by a "fast-redirects"
179 * line in the config file, has its own log level
180 * and of course wants to be displayed by show-proxy-args
181 * Note: Boy, all the #ifdefs in 1001 locations and
182 * all the fumbling with configure.in and acconfig.h
183 * were *way* more work than the feature itself :-(
185 * - Because a generic redirect template was needed for
186 * this, tinygif = 3 now uses the same.
188 * - Moved GIFs, and other static HTTP response templates
193 * - Removed some >400 CRs again (Jon, you really worked
196 * Revision 1.2 2001/05/20 01:21:20 jongfoster
197 * Version 2.9.4 checkin.
198 * - Merged popupfile and cookiefile, and added control over PCRS
199 * filtering, in new "permissionsfile".
200 * - Implemented LOG_LEVEL_FATAL, so that if there is a configuration
201 * file error you now get a message box (in the Win32 GUI) rather
202 * than the program exiting with no explanation.
203 * - Made killpopup use the PCRS MIME-type checking and HTTP-header
205 * - Removed tabs from "config"
206 * - Moved duplicated url parsing code in "loaders.c" to a new funcition.
207 * - Bumped up version number.
209 * Revision 1.1.1.1 2001/05/15 13:58:52 oes
210 * Initial import of version 2.9.3 source tree
213 *********************************************************************/
223 struct access_control_addr;
226 struct http_response;
227 struct current_action_spec;
236 extern int block_acl(struct access_control_addr *dst, struct client_state *csp);
237 extern int acl_addr(char *aspec, struct access_control_addr *aca);
238 #endif /* def FEATURE_ACL */
239 extern int match_portlist(const char *portlist, int port);
244 extern struct http_response *block_url(struct client_state *csp);
245 extern struct http_response *redirect_url(struct client_state *csp);
247 extern struct http_response *trust_url(struct client_state *csp);
248 #endif /* def FEATURE_TRUST */
254 extern int is_untrusted_url(struct client_state *csp);
255 #endif /* def FEATURE_TRUST */
256 #ifdef FEATURE_IMAGE_BLOCKING
257 extern int is_imageurl(struct client_state *csp);
258 #endif /* def FEATURE_IMAGE_BLOCKING */
261 * Determining applicable actions
263 extern void url_actions(struct http_request *http,
264 struct client_state *csp);
265 extern void apply_url_actions(struct current_action_spec *action,
266 struct http_request *http,
267 struct url_actions *b);
269 * Determining parent proxies
271 extern const struct forward_spec *forward_url(struct http_request *http, struct client_state *csp);
274 * Content modification
276 extern char *pcrs_filter_response(struct client_state *csp);
277 extern char *gif_deanimate_response(struct client_state *csp);
278 extern char *jpeg_inspect_response(struct client_state *csp);
279 extern int remove_chunked_transfer_coding(char *buffer, const size_t size);
280 extern char *execute_single_pcrs_command(char *subject, const char *pcrs_command, int *hits);
281 extern char *rewrite_url(char *old_url, const char *pcrs_command);
282 extern char *get_last_url(char *subject, const char *redirect_mode);
285 * Handling Max-Forwards:
287 extern struct http_response *direct_response( struct client_state *csp);
294 #define INADDR_NONE -1
298 * Revision control strings from this header and associated .c file
300 extern const char filters_rcs[];
301 extern const char filters_h_rcs[];
307 #endif /* ndef FILTERS_H_INCLUDED */