1 #ifndef FILTERS_H_INCLUDED
2 #define FILTERS_H_INCLUDED
3 #define FILTERS_H_VERSION "$Id: filters.h,v 1.23 2006/11/28 15:19:43 fabiankeil 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 1.23 2006/11/28 15:19:43 fabiankeil
43 * Implemented +redirect{s@foo@bar@} to generate
44 * a redirect based on a rewritten version of the
47 * Revision 1.22 2006/07/18 14:48:46 david__schmidt
48 * Reorganizing the repository: swapping out what was HEAD (the old 3.1 branch)
49 * with what was really the latest development (the v_3_0_branch branch)
51 * Revision 1.20.2.2 2004/10/03 12:53:32 david__schmidt
52 * Add the ability to check jpeg images for invalid
53 * lengths of comment blocks. Defensive strategy
54 * against the exploit:
55 * Microsoft Security Bulletin MS04-028
56 * Buffer Overrun in JPEG Processing (GDI+) Could
57 * Allow Code Execution (833987)
58 * Enabled with +inspect-jpegs in actions files.
60 * Revision 1.20.2.1 2002/09/25 14:51:51 oes
61 * Added basic support for OPTIONS and TRACE HTTP methods:
62 * New function direct_response which handles OPTIONS and
63 * TRACE requests whose Max-Forwards header field is zero.
65 * Revision 1.20 2002/04/02 14:56:16 oes
66 * Bugfix: is_untrusted_url() and trust_url() now depend on FEATURE_TRUST, not FEATURE_COOKIE_JAR
68 * Revision 1.19 2002/03/26 22:29:54 swa
69 * we have a new homepage!
71 * Revision 1.18 2002/03/25 22:12:45 oes
72 * Added fix for undefined INADDR_NONE on Solaris by Bart Schelstraete
74 * Revision 1.17 2002/03/24 13:25:43 swa
75 * name change related issues
77 * Revision 1.16 2002/01/17 21:01:02 jongfoster
78 * Moving all our URL and URL pattern parsing code to urlmatch.c.
80 * Revision 1.15 2001/10/10 16:44:16 oes
81 * Added match_portlist function
83 * Revision 1.14 2001/10/07 15:41:40 oes
84 * Added prototype for remove_chunked_transfer_coding
86 * Revision 1.13 2001/07/30 22:08:36 jongfoster
87 * Tidying up #defines:
88 * - All feature #defines are now of the form FEATURE_xxx
89 * - Permanently turned off WIN_GUI_EDIT
90 * - Permanently turned on WEBDAV and SPLIT_PROXY_ARGS
92 * Revision 1.12 2001/07/29 19:01:11 jongfoster
93 * Changed _FILENAME_H to FILENAME_H_INCLUDED.
94 * Added forward declarations for needed structures.
96 * Revision 1.11 2001/07/13 14:00:18 oes
97 * - Introduced gif_deanimate_response
98 * - Renamed re_process_buffer to pcrs_filter_response
99 * - Removed all #ifdef PCRS
101 * Revision 1.10 2001/06/29 13:29:01 oes
102 * Cleaned up and updated to reflect the changesin
105 * Revision 1.9 2001/06/07 23:10:53 jongfoster
106 * Replacing struct gateway with struct forward_spec
108 * Revision 1.8 2001/06/03 19:12:00 oes
109 * extracted-CGI relevant stuff
111 * Revision 1.7 2001/05/31 21:21:30 jongfoster
112 * Permissionsfile / actions file changes:
113 * - Changed "permission" to "action" throughout
114 * - changes to file format to allow string parameters
115 * - Moved helper functions to actions.c
117 * Revision 1.6 2001/05/29 09:50:24 jongfoster
118 * Unified blocklist/imagelist/permissionslist.
119 * File format is still under discussion, but the internal changes
122 * Also modified interceptor behaviour:
123 * - We now intercept all URLs beginning with one of the following
124 * prefixes (and *only* these prefixes):
126 * * http://ijbswa.sf.net/config/
127 * * http://ijbswa.sourceforge.net/config/
128 * - New interceptors "home page" - go to http://i.j.b/ to see it.
129 * - Internal changes so that intercepted and fast redirect pages
130 * are not replaced with an image.
131 * - Interceptors now have the option to send a binary page direct
132 * to the client. (i.e. ijb-send-banner uses this)
133 * - Implemented show-url-info interceptor. (Which is why I needed
134 * the above interceptors changes - a typical URL is
135 * "http://i.j.b/show-url-info?url=www.somesite.com/banner.gif".
136 * The previous mechanism would not have intercepted that, and
137 * if it had been intercepted then it then it would have replaced
140 * Revision 1.5 2001/05/27 22:17:04 oes
142 * - re_process_buffer no longer writes the modified buffer
143 * to the client, which was very ugly. It now returns the
144 * buffer, which it is then written by chat.
146 * - content_length now adjusts the Content-Length: header
147 * for modified documents rather than crunch()ing it.
148 * (Length info in csp->content_length, which is 0 for
149 * unmodified documents)
151 * - For this to work, sed() is called twice when filtering.
153 * Revision 1.4 2001/05/26 15:26:15 jongfoster
154 * ACL feature now provides more security by immediately dropping
155 * connections from untrusted hosts.
157 * Revision 1.3 2001/05/22 18:46:04 oes
159 * - Enabled filtering banners by size rather than URL
160 * by adding patterns that replace all standard banner
161 * sizes with the "Junkbuster" gif to the re_filterfile
163 * - Enabled filtering WebBugs by providing a pattern
164 * which kills all 1x1 images
166 * - Added support for PCRE_UNGREEDY behaviour to pcrs,
167 * which is selected by the (nonstandard and therefore
168 * capital) letter 'U' in the option string.
169 * It causes the quantifiers to be ungreedy by default.
170 * Appending a ? turns back to greedy (!).
172 * - Added a new interceptor ijb-send-banner, which
173 * sends back the "Junkbuster" gif. Without imagelist or
174 * MSIE detection support, or if tinygif = 1, or the
175 * URL isn't recognized as an imageurl, a lame HTML
176 * explanation is sent instead.
178 * - Added new feature, which permits blocking remote
179 * script redirects and firing back a local redirect
181 * The feature is conditionally compiled, i.e. it
182 * can be disabled with --disable-fast-redirects,
183 * plus it must be activated by a "fast-redirects"
184 * line in the config file, has its own log level
185 * and of course wants to be displayed by show-proxy-args
186 * Note: Boy, all the #ifdefs in 1001 locations and
187 * all the fumbling with configure.in and acconfig.h
188 * were *way* more work than the feature itself :-(
190 * - Because a generic redirect template was needed for
191 * this, tinygif = 3 now uses the same.
193 * - Moved GIFs, and other static HTTP response templates
198 * - Removed some >400 CRs again (Jon, you really worked
201 * Revision 1.2 2001/05/20 01:21:20 jongfoster
202 * Version 2.9.4 checkin.
203 * - Merged popupfile and cookiefile, and added control over PCRS
204 * filtering, in new "permissionsfile".
205 * - Implemented LOG_LEVEL_FATAL, so that if there is a configuration
206 * file error you now get a message box (in the Win32 GUI) rather
207 * than the program exiting with no explanation.
208 * - Made killpopup use the PCRS MIME-type checking and HTTP-header
210 * - Removed tabs from "config"
211 * - Moved duplicated url parsing code in "loaders.c" to a new funcition.
212 * - Bumped up version number.
214 * Revision 1.1.1.1 2001/05/15 13:58:52 oes
215 * Initial import of version 2.9.3 source tree
218 *********************************************************************/
228 struct access_control_addr;
231 struct http_response;
232 struct current_action_spec;
241 extern int block_acl(struct access_control_addr *dst, struct client_state *csp);
242 extern int acl_addr(char *aspec, struct access_control_addr *aca);
243 #endif /* def FEATURE_ACL */
244 extern int match_portlist(const char *portlist, int port);
249 extern struct http_response *block_url(struct client_state *csp);
250 extern struct http_response *redirect_url(struct client_state *csp);
252 extern struct http_response *trust_url(struct client_state *csp);
253 #endif /* def FEATURE_TRUST */
259 extern int is_untrusted_url(struct client_state *csp);
260 #endif /* def FEATURE_TRUST */
261 #ifdef FEATURE_IMAGE_BLOCKING
262 extern int is_imageurl(struct client_state *csp);
263 #endif /* def FEATURE_IMAGE_BLOCKING */
266 * Determining applicable actions
268 extern void url_actions(struct http_request *http,
269 struct client_state *csp);
270 extern void apply_url_actions(struct current_action_spec *action,
271 struct http_request *http,
272 struct url_actions *b);
274 * Determining parent proxies
276 extern const struct forward_spec *forward_url(struct http_request *http, struct client_state *csp);
279 * Content modification
281 extern char *pcrs_filter_response(struct client_state *csp);
282 extern char *gif_deanimate_response(struct client_state *csp);
283 extern char *jpeg_inspect_response(struct client_state *csp);
284 extern size_t remove_chunked_transfer_coding(char *buffer, const size_t size);
285 extern char *execute_single_pcrs_command(char *subject, const char *pcrs_command, int *hits);
286 extern char *rewrite_url(char *old_url, const char *pcrs_command);
287 extern char *get_last_url(char *subject, const char *redirect_mode);
290 * Handling Max-Forwards:
292 extern struct http_response *direct_response( struct client_state *csp);
299 #define INADDR_NONE -1
303 * Revision control strings from this header and associated .c file
305 extern const char filters_rcs[];
306 extern const char filters_h_rcs[];
312 #endif /* ndef FILTERS_H_INCLUDED */