2 File : $Source: /cvsroot/ijbswa/current/doc/source/p-config.sgml,v $
4 Purpose : Used with other docs and files only.
6 $Id: p-config.sgml,v 2.53 2009/06/12 11:53:33 fabiankeil Exp $
8 Copyright (C) 2001-2009 Privoxy Developers http://www.privoxy.org/
11 ========================================================================
12 NOTE: Please read developer-manual/documentation.html before touching
13 anything in this, or other Privoxy documentation.
14 ========================================================================
17 This file contains all the config file comments and options. It used to
18 build both the user-manual config sections, and all of config (yes, the main
21 Rationale: This is broken up into two files since a file with a prolog
22 (DTD, etc) cannot be sourced as a secondary file. config.sgml is basically
23 a wrapper for this file.
27 OPTIONS: The actual options are included in this file and prefixed with
28 '@@', and processed by the Makefile to strip the '@@'. Default options
29 that should appear commented out should be listed as: '@@#OPTION'.
30 Otherwise, as '@@OPTION'. Example:
32 @@listen-address 127.0.0.1:8118
34 The Makefile does significant other processing too. The final results
35 should be checked to make sure that the perl processing does not
36 fubar something!!! Makefile processing requires w3m, fmt (shell line
40 This file is included into:
43 config (the actual Privoxy config file)
48 <!-- This part only goes into user-manual -->
50 <title>The Main Configuration File</title>
53 Again, the main configuration file is named <filename>config</filename> on
54 Linux/Unix/BSD and OS/2, and <filename>config.txt</filename> on Windows.
55 Configuration lines consist of an initial keyword followed by a list of
56 values, all separated by whitespace (any number of spaces or tabs). For
64 <emphasis>confdir /etc/privoxy</emphasis></literallayout>
70 Assigns the value <literal>/etc/privoxy</literal> to the option
71 <literal>confdir</literal> and thus indicates that the configuration
72 directory is named <quote>/etc/privoxy/</quote>.
76 All options in the config file except for <literal>confdir</literal> and
77 <literal>logdir</literal> are optional. Watch out in the below description
78 for what happens if you leave them unset.
82 The main config file controls all aspects of <application>Privoxy</application>'s
83 operation that are not location dependent (i.e. they apply universally, no matter
84 where you may be surfing). Like the filter and action files, the config file is
85 a plain text file and can be modified with a text editor like emacs, vim or
93 <!-- This part only goes into the config file -->
96 @@TITLE<!-- between the @@ is stripped by Makefile -->@@
97 Sample Configuration File for Privoxy v&p-version;
100 $Id: p-config.sgml,v 2.53 2009/06/12 11:53:33 fabiankeil Exp $
103 Copyright (C) 2001-2009 Privoxy Developers http://www.privoxy.org/
108 #################################################################
113 II. FORMAT OF THE CONFIGURATION FILE #
115 1. LOCAL SET-UP DOCUMENTATION #
116 2. CONFIGURATION AND LOG FILE LOCATIONS #
118 4. ACCESS CONTROL AND SECURITY #
120 6. WINDOWS GUI OPTIONS #
122 #################################################################
126 <literallayout>I. INTRODUCTION
127 =============== <!-- fuck this madness --></literallayout>
130 This file holds Privoxy's main configuration. Privoxy detects
131 configuration changes automatically, so you don't have to restart it
132 unless you want to load a different configuration file.
135 The configuration will be reloaded with the first request after the
136 change was done, this request itself will still use the old configuration,
137 though. In other words: it takes two requests before you see the result of
138 your changes. Requests that are dropped due to ACL don't trigger reloads.
141 When starting Privoxy on Unix systems, give the location of this
142 file as last argument. On Windows systems, Privoxy will look for
143 this file with the name 'config.txt' in the current working directory
144 of the Privoxy process.
148 <literallayout><!-- funky spacing -->
150 II. FORMAT OF THE CONFIGURATION FILE
151 ====================================</literallayout>
154 Configuration lines consist of an initial keyword followed by a list
155 of values, all separated by whitespace (any number of spaces or
159 actionsfile default.action
162 Indicates that the actionsfile is named 'default.action'.
165 The '#' indicates a comment. Any part of a line following a '#' is
166 ignored, except if the '#' is preceded by a '\'.
169 Thus, by placing a # at the start of an existing configuration line,
170 you can make it a comment and it will be treated as if it weren't there.
171 This is called "commenting out" an option and can be useful. Removing
172 the # again is called "uncommenting".
175 Note that commenting out an option and leaving it at its default
176 are two completely different things! Most options behave very
177 differently when unset. See the "Effect if unset" explanation
178 in each option's description for details.
181 Long lines can be continued on the next line by using a `\' as
187 <!-- ************************************************ -->
188 <!-- The following is common to both outputs (mostly) -->
189 <!-- ************************************************ -->
193 <!-- ~~~~~ New section ~~~~~ -->
194 <sect2 id="local-set-up">
195 <title>Local Set-up Documentation</title>
198 If you intend to operate <application>Privoxy</application> for more users
199 than just yourself, it might be a good idea to let them know how to reach
200 you, what you block and why you do that, your policies, etc.
204 <!-- ~~~~~ New section ~~~~~ -->
205 <sect3 renderas="sect4" id="user-manual"><title>user-manual</title>
208 <term>Specifies:</term>
211 Location of the <application>Privoxy</application> User Manual.
216 <term>Type of value:</term>
218 <para>A fully qualified URI</para>
222 <term>Default value:</term>
224 <para><emphasis>Unset</emphasis></para>
228 <term>Effect if unset:</term>
231 <ulink url="http://www.privoxy.org/user-manual/">http://www.privoxy.org/<replaceable class="parameter">version</replaceable>/user-manual/</ulink>
232 will be used, where <replaceable class="parameter">version</replaceable> is the <application>Privoxy</application> version.
240 The User Manual URI is the single best source of information on
241 <application>Privoxy</application>, and is used for help links from some
242 of the internal CGI pages. The manual itself is normally packaged with the
243 binary distributions, so you probably want to set this to a locally
251 Unix, in local filesystem (may not work with all browsers):
254 <screen> user-manual file:///usr/share/doc/privoxy-&p-version;/user-manual/</screen>
257 Windows, in local filesystem, <emphasis>must</emphasis> use forward slash notation:
260 <screen> user-manual file:/c:/some-dir/privoxy-&p-version;/user-manual/</screen>
263 Windows, UNC notation (with forward slashes):
266 <screen> user-manual file://///some-server/some-path/privoxy-&p-version;/user-manual/</screen>
270 The best all purpose solution is simply to put the full local
271 <literal>PATH</literal> to where the <citetitle>User Manual</citetitle> is
275 <screen> user-manual /usr/share/doc/privoxy/user-manual</screen>
278 The User Manual is then available to anyone with access to
279 <application>Privoxy</application>, by following the built-in URL:
280 <literal>http://config.privoxy.org/user-manual/</literal>
281 (or the shortcut: <literal>http://p.p/user-manual/</literal>).
284 If the documentation is not on the local system, it can be accessed
285 from a remote server, as:
288 <screen> user-manual http://example.com/privoxy/user-manual/</screen>
291 <!-- this gets hammered in conversion to config. Text repeated below. -->
294 If set, this option should be <emphasis>the first option in the config
295 file</emphasis>, because it is used while the config file is being read
308 If set, this option should be the first option in the config
309 file, because it is used while the config file is being read.
318 <![%config-file;[<literallayout>@@#user-manual http://www.privoxy.org/user-manual/</literallayout>]]>
322 <!-- ~~~~~ New section ~~~~~ -->
323 <sect3 renderas="sect4" id="trust-info-url"><title>trust-info-url</title>
327 <term>Specifies:</term>
330 A URL to be displayed in the error page that users will see if access to an untrusted page is denied.
335 <term>Type of value:</term>
341 <term>Default value:</term>
343 <para><emphasis>Unset</emphasis></para>
347 <term>Effect if unset:</term>
350 No links are displayed on the "untrusted" error page.
358 The value of this option only matters if the experimental trust mechanism has been
359 activated. (See <link linkend="trustfile"><emphasis>trustfile</emphasis></link> below.)
362 If you use the trust mechanism, it is a good idea to write up some on-line
363 documentation about your trust policy and to specify the URL(s) here.
364 Use multiple times for multiple URLs.
367 The URL(s) should be added to the trustfile as well, so users don't end up
368 locked out from the information on why they were locked out in the first place!
374 <![%config-file;[<literallayout>@@#trust-info-url http://www.example.com/why_we_block.html</literallayout>]]>
375 <![%config-file;[<literallayout>@@#trust-info-url http://www.example.com/what_we_allow.html</literallayout>]]>
379 <!-- ~~~~~ New section ~~~~~ -->
380 <sect3 renderas="sect4" id="admin-address"><title>admin-address</title>
384 <term>Specifies:</term>
387 An email address to reach the <application>Privoxy</application> administrator.
392 <term>Type of value:</term>
394 <para>Email address</para>
398 <term>Default value:</term>
400 <para><emphasis>Unset</emphasis></para>
404 <term>Effect if unset:</term>
407 No email address is displayed on error pages and the CGI user interface.
415 If both <literal>admin-address</literal> and <literal>proxy-info-url</literal>
416 are unset, the whole "Local Privoxy Support" box on all generated pages will
423 <![%config-file;[<literallayout>@@#admin-address privoxy-admin@example.com</literallayout>]]>
427 <!-- ~~~~~ New section ~~~~~ -->
428 <sect3 renderas="sect4" id="proxy-info-url"><title>proxy-info-url</title>
432 <term>Specifies:</term>
435 A URL to documentation about the local <application>Privoxy</application> setup,
436 configuration or policies.
441 <term>Type of value:</term>
447 <term>Default value:</term>
449 <para><emphasis>Unset</emphasis></para>
453 <term>Effect if unset:</term>
456 No link to local documentation is displayed on error pages and the CGI user interface.
464 If both <literal>admin-address</literal> and <literal>proxy-info-url</literal>
465 are unset, the whole "Local Privoxy Support" box on all generated pages will
469 This URL shouldn't be blocked ;-)
475 <![%config-file;[<literallayout>@@#proxy-info-url http://www.example.com/proxy-service.html</literallayout>]]>
479 <!-- ~ End section ~ -->
483 <!-- ~~~~~ New section ~~~~~ -->
485 <sect2 id="conf-log-loc">
486 <title>Configuration and Log File Locations</title>
489 <application>Privoxy</application> can (and normally does) use a number of
490 other files for additional configuration, help and logging.
491 This section of the configuration file tells <application>Privoxy</application>
492 where to find those other files.
496 The user running <application>Privoxy</application>, must have read
497 permission for all configuration files, and write permission to any files
498 that would be modified, such as log files and actions files.
502 <!-- ~~~~~ New section ~~~~~ -->
503 <sect3 renderas="sect4" id="confdir"><title>confdir</title>
507 <term>Specifies:</term>
509 <para>The directory where the other configuration files are located.</para>
513 <term>Type of value:</term>
515 <para>Path name</para>
519 <term>Default value:</term>
521 <para>/etc/privoxy (Unix) <emphasis>or</emphasis> <application>Privoxy</application> installation dir (Windows) </para>
525 <term>Effect if unset:</term>
527 <para><emphasis>Mandatory</emphasis></para>
534 No trailing <quote><literal>/</literal></quote>, please.
537 This is really outdated and not likely to happen. HB 09/20/06
539 When development goes modular and multi-user, the blocker, filter, and
540 per-user config will be stored in subdirectories of <quote>confdir</quote>.
541 For now, the configuration directory structure is flat, except for
542 <filename>confdir/templates</filename>, where the HTML templates for CGI
543 output reside (e.g. <application>Privoxy's</application> 404 error page).
550 <![%config-file;[<literallayout>@@confdir .</literallayout>]]>
553 <!-- ~~~~~ New section ~~~~~ -->
554 <sect3 renderas="sect4" id="templdir"><title>templdir</title>
558 <term>Specifies:</term>
560 <para>An alternative directory where the templates are loaded from.</para>
564 <term>Type of value:</term>
566 <para>Path name</para>
570 <term>Default value:</term>
576 <term>Effect if unset:</term>
578 <para>The templates are assumed to be located in confdir/template.</para>
585 <application>Privoxy's</application> original templates are usually
586 overwritten with each update. Use this option to relocate customized
587 templates that should be kept. As template variables might change
588 between updates, you shouldn't expect templates to work with
589 <application>Privoxy</application> releases other than the one
590 they were part of, though.
596 <![%config-file;[<literallayout>@@#templdir .</literallayout>]]>
600 <!-- ~~~~~ New section ~~~~~ -->
601 <sect3 renderas="sect4" id="logdir"><title>logdir</title>
605 <term>Specifies:</term>
608 The directory where all logging takes place
609 (i.e. where the <filename>logfile</filename> is located).
614 <term>Type of value:</term>
616 <para>Path name</para>
620 <term>Default value:</term>
622 <para>/var/log/privoxy (Unix) <emphasis>or</emphasis> <application>Privoxy</application> installation dir (Windows) </para>
626 <term>Effect if unset:</term>
628 <para><emphasis>Mandatory</emphasis></para>
635 No trailing <quote><literal>/</literal></quote>, please.
641 <![%config-file;[<literallayout>@@logdir .</literallayout>]]>
645 <!-- ~~~~~ New section ~~~~~ -->
646 <sect3 renderas="sect4" id="actionsfile"><title>
649 <anchor id="default.action">
650 <anchor id="standard.action">
651 <anchor id="user.action">
652 <!-- Note: slightly modified this section 04/28/02, hal. See NOTE. -->
655 <term>Specifies:</term>
658 The <link linkend="actions-file">actions file(s)</link> to use
663 <term>Type of value:</term>
665 <para>Complete file name, relative to <literal>confdir</literal></para>
669 <term>Default values:</term>
673 <msgtext><literallayout> match-all.action # Actions that are applied to all sites and maybe overruled later on.</literallayout></msgtext>
676 <msgtext><literallayout> default.action # Main actions file</literallayout></msgtext>
679 <msgtext><literallayout> user.action # User customizations</literallayout></msgtext>
685 <term>Effect if unset:</term>
688 No actions are taken at all. More or less neutral proxying.
696 Multiple <literal>actionsfile</literal> lines are permitted, and are in fact recommended!
699 The default values are <filename>default.action</filename>, which is the
700 <quote>main</quote> actions file maintained by the developers, and
701 <filename>user.action</filename>, where you can make your personal additions.
704 Actions files contain all the per site and per URL configuration for
705 ad blocking, cookie management, privacy considerations, etc.
706 There is no point in using <application>Privoxy</application> without at
707 least one actions file.
710 Note that since Privoxy 3.0.7, the complete filename, including the <quote>.action</quote>
711 extension has to be specified. The syntax change was necessary to be consistent
712 with the other file options and to allow previously forbidden characters.
718 <!-- NOTE: alternate markup to make a simpler list doesn't work due to -->
719 <!-- html -> text conversion, blah -->
720 <![%config-file;[<literallayout>@@actionsfile match-all.action # Actions that are applied to all sites and maybe overruled later on.</literallayout>]]>
721 <![%config-file;[<literallayout>@@actionsfile default.action # Main actions file</literallayout>]]>
723 XXX: Like user.filter, user.action should probably be commented out
724 by default as not all packages install it into the default directory.
727 <![%config-file;[<literallayout>@@actionsfile user.action # User customizations</literallayout>]]>
730 <!-- ~~~~~ New section ~~~~~ -->
731 <sect3 renderas="sect4" id="filterfile"><title>filterfile</title>
732 <anchor id="default.filter">
735 <term>Specifies:</term>
738 The <link linkend="filter-file">filter file(s)</link> to use
743 <term>Type of value:</term>
745 <para>File name, relative to <literal>confdir</literal></para>
749 <term>Default value:</term>
751 <para>default.filter (Unix) <emphasis>or</emphasis> default.filter.txt (Windows)</para>
755 <term>Effect if unset:</term>
758 No textual content filtering takes place, i.e. all
759 <literal>+<link linkend="filter">filter</link>{<replaceable class="parameter">name</replaceable>}</literal>
760 actions in the actions files are turned neutral.
768 Multiple <literal>filterfile</literal> lines are permitted.
771 The <link linkend="filter-file">filter files</link> contain content modification
772 rules that use <link linkend="regex">regular expressions</link>. These rules permit
773 powerful changes on the content of Web pages, and optionally the headers
774 as well, e.g., you could try to disable your favorite JavaScript annoyances,
775 re-write the actual displayed text, or just have some fun
776 playing buzzword bingo with web pages.
780 <literal>+<link linkend="filter">filter</link>{<replaceable class="parameter">name</replaceable>}</literal>
781 actions rely on the relevant filter (<replaceable class="parameter">name</replaceable>)
782 to be defined in a filter file!
785 A pre-defined filter file called <filename>default.filter</filename> that contains
786 a number of useful filters for common problems is included in the distribution.
787 See the section on the <literal><link linkend="filter">filter</link></literal>
791 It is recommended to place any locally adapted filters into a separate
792 file, such as <filename>user.filter</filename>.
798 <![%config-file;[<literallayout>@@filterfile default.filter</literallayout>]]>
799 <![%config-file;[<literallayout>@@#filterfile user.filter # User customizations</literallayout>]]>
803 <!-- ~~~~~ New section ~~~~~ -->
804 <sect3 renderas="sect4" id="logfile"><title>logfile</title>
808 <term>Specifies:</term>
816 <term>Type of value:</term>
818 <para>File name, relative to <literal>logdir</literal></para>
822 <term>Default value:</term>
824 <para><emphasis>Unset (commented out)</emphasis>. When activated: logfile (Unix) <emphasis>or</emphasis> privoxy.log (Windows).</para>
828 <term>Effect if unset:</term>
831 No logfile is written.
839 The logfile is where all logging and error messages are written. The level
840 of detail and number of messages are set with the <literal>debug</literal>
841 option (see below). The logfile can be useful for tracking down a problem with
842 <application>Privoxy</application> (e.g., it's not blocking an ad you
843 think it should block) and it can help you to monitor what your browser
847 Depending on the debug options below, the logfile may be a privacy risk
848 if third parties can get access to it. As most users will never look
849 at it, <application>Privoxy</application> 3.0.7 and later only log fatal
853 For most troubleshooting purposes, you will have to change that,
854 please refer to the debugging section for details.
857 Your logfile will grow indefinitely, and you will probably want to
858 periodically remove it. On Unix systems, you can do this with a cron job
859 (see <quote>man cron</quote>). For Red Hat based Linux distributions, a
860 <command>logrotate</command> script has been included.
863 Any log files must be writable by whatever user <application>Privoxy</application>
864 is being run as (on Unix, default user id is <quote>privoxy</quote>).
870 <![%config-file;[<literallayout>@@logfile logfile</literallayout>]]>
874 <!-- ~~~~~ New section ~~~~~ -->
875 <sect3 renderas="sect4" id="trustfile"><title>trustfile</title>
878 <term>Specifies:</term>
881 The name of the trust file to use
886 <term>Type of value:</term>
888 <para>File name, relative to <literal>confdir</literal></para>
892 <term>Default value:</term>
894 <para><emphasis>Unset (commented out)</emphasis>. When activated: trust (Unix) <emphasis>or</emphasis> trust.txt (Windows)</para>
898 <term>Effect if unset:</term>
901 The entire trust mechanism is disabled.
909 The trust mechanism is an experimental feature for building white-lists and should
910 be used with care. It is <emphasis>NOT</emphasis> recommended for the casual user.
913 If you specify a trust file, <application>Privoxy</application> will only allow
914 access to sites that are specified in the trustfile. Sites can be listed
918 Prepending a <literal>~</literal> character limits access to this site
919 only (and any sub-paths within this site), e.g.
920 <literal>~www.example.com</literal> allows access to
921 <literal>~www.example.com/features/news.html</literal>, etc.
924 Or, you can designate sites as <emphasis>trusted referrers</emphasis>, by
925 prepending the name with a <literal>+</literal> character. The effect is that
926 access to untrusted sites will be granted -- but only if a link from this
927 trusted referrer was used to get there. The link target will then be added
928 to the <quote>trustfile</quote> so that future, direct accesses will be
929 granted. Sites added via this mechanism do not become trusted referrers
930 themselves (i.e. they are added with a <literal>~</literal> designation).
931 There is a limit of 512 such entries, after which new entries will not be
935 If you use the <literal>+</literal> operator in the trust file, it may grow
936 considerably over time.
939 It is recommended that <application>Privoxy</application> be compiled with
940 the <literal>--disable-force</literal>, <literal>--disable-toggle</literal> and
941 <literal> --disable-editor</literal> options, if this feature is to be
945 Possible applications include limiting Internet access for children.
952 <![%config-file;[<literallayout>@@#trustfile trust</literallayout>]]>
956 <!-- ~ End section ~ -->
958 <!-- ~~~~~ New section ~~~~~ -->
959 <sect2 id="debugging">
960 <title>Debugging</title>
963 These options are mainly useful when tracing a problem.
964 Note that you might also want to invoke
965 <application>Privoxy</application> with the <literal>--no-daemon</literal>
966 command line option when debugging.
969 <sect3 renderas="sect4" id="debug"><title>debug</title>
973 <term>Specifies:</term>
976 Key values that determine what information gets logged.
981 <term>Type of value:</term>
983 <para>Integer values</para>
987 <term>Default value:</term>
989 <para>0 (i.e.: only fatal errors (that cause Privoxy to exit) are logged)</para>
993 <term>Effect if unset:</term>
996 Default value is used (see above).
1004 The available debug levels are:
1008 debug 1 # Log the destination for each request &my-app; let through. See also debug 1024.
1009 debug 2 # show each connection status
1010 debug 4 # show I/O status
1011 debug 8 # show header parsing
1012 debug 16 # log all data written to the network into the logfile
1013 debug 32 # debug force feature
1014 debug 64 # debug regular expression filters
1015 debug 128 # debug redirects
1016 debug 256 # debug GIF de-animation
1017 debug 512 # Common Log Format
1018 debug 1024 # Log the destination for requests &my-app; didn't let through, and the reason why.
1019 debug 2048 # CGI user interface
1020 debug 4096 # Startup banner and warnings.
1021 debug 8192 # Non-fatal errors
1025 To select multiple debug levels, you can either add them or use
1026 multiple <literal>debug</literal> lines.
1029 A debug level of 1 is informative because it will show you each request
1030 as it happens. <emphasis>1, 1024, 4096 and 8192 are recommended</emphasis>
1031 so that you will notice when things go wrong. The other levels are
1032 probably only of interest if you are hunting down a specific problem.
1033 They can produce a hell of an output (especially 16).
1037 &my-app; used to ship with the debug levels recommended above enabled by
1038 default, but due to privacy concerns 3.0.7 and later are configured to
1039 only log fatal errors.
1042 If you are used to the more verbose settings, simply enable the debug lines
1046 If you want to use pure CLF (Common Log Format), you should set <quote>debug
1047 512</quote> <emphasis>ONLY</emphasis> and not enable anything else.
1050 <application>Privoxy</application> has a hard-coded limit for the
1051 length of log messages. If it's reached, messages are logged truncated
1052 and marked with <quote>... [too long, truncated]</quote>.
1055 Please don't file any support requests without trying to reproduce
1056 the problem with increased debug level first. Once you read the log
1057 messages, you may even be able to solve the problem on your own.
1063 <![%config-file;[<literallayout>@@#debug 1 # Log the destination for each request &my-app; let through.</literallayout>]]>
1064 <![%config-file;[<literallayout>@@#debug 1024 # Log the destination for requests &my-app; didn't let through, and the reason why.</literallayout>]]>
1065 <![%config-file;[<literallayout>@@#debug 4096 # Startup banner and warnings</literallayout>]]>
1066 <![%config-file;[<literallayout>@@#debug 8192 # Non-fatal errors</literallayout>]]>
1070 <!-- ~~~~~ New section ~~~~~ -->
1071 <sect3 renderas="sect4" id="single-threaded"><title>single-threaded</title>
1075 <term>Specifies:</term>
1078 Whether to run only one server thread.
1083 <term>Type of value:</term>
1085 <para><emphasis>None</emphasis></para>
1089 <term>Default value:</term>
1091 <para><emphasis>Unset</emphasis></para>
1095 <term>Effect if unset:</term>
1098 Multi-threaded (or, where unavailable: forked) operation, i.e. the ability to
1099 serve multiple requests simultaneously.
1107 This option is only there for debugging purposes.
1108 <emphasis>It will drastically reduce performance.</emphasis>
1114 <![%config-file;[<literallayout>@@#single-threaded</literallayout>]]>
1117 <!-- ~~~~~ New section ~~~~~ -->
1118 <sect3 renderas="sect4" id="hostname"><title>hostname</title>
1122 <term>Specifies:</term>
1125 The hostname shown on the CGI pages.
1130 <term>Type of value:</term>
1136 <term>Default value:</term>
1138 <para><emphasis>Unset</emphasis></para>
1142 <term>Effect if unset:</term>
1145 The hostname provided by the operating system is used.
1153 On some misconfigured systems resolving the hostname fails or
1154 takes too much time and slows Privoxy down. Setting a fixed hostname
1155 works around the problem.
1158 In other circumstances it might be desirable to show a hostname
1159 other than the one returned by the operating system. For example
1160 if the system has several different hostnames and you don't want
1161 to use the first one.
1164 Note that Privoxy does not validate the specified hostname value.
1170 <![%config-file;[<literallayout>@@#hostname hostname.example.org</literallayout>]]>
1175 <!-- ~ End section ~ -->
1178 <!-- ~~~~~ New section ~~~~~ -->
1179 <sect2 id="access-control">
1180 <title>Access Control and Security</title>
1183 This section of the config file controls the security-relevant aspects
1184 of <application>Privoxy</application>'s configuration.
1188 <!-- ~~~~~ New section ~~~~~ -->
1189 <sect3 renderas="sect4" id="listen-address"><title>listen-address</title>
1193 <term>Specifies:</term>
1196 The IP address and TCP port on which <application>Privoxy</application> will
1197 listen for client requests.
1202 <term>Type of value:</term>
1204 <para>[<replaceable class="parameter">IP-Address</replaceable>]:<replaceable class="parameter">Port</replaceable></para>
1209 <term>Default value:</term>
1211 <para>127.0.0.1:8118</para>
1215 <term>Effect if unset:</term>
1218 Bind to 127.0.0.1 (IPv4 localhost), port 8118. This is suitable and
1219 recommended for home users who run <application>Privoxy</application> on
1220 the same machine as their browser.
1228 You will need to configure your browser(s) to this proxy address and port.
1231 If you already have another service running on port 8118, or if you want to
1232 serve requests from other machines (e.g. on your local network) as well, you
1233 will need to override the default.
1236 IPv6 addresses containing colons have to be quoted by brackets.
1239 If you leave out the IP address, <application>Privoxy</application> will
1240 bind to all IPv4 interfaces (addresses) on your machine and may become reachable
1241 from the Internet. In that case, consider using <link
1242 linkend="acls">access control lists</link> (ACL's, see below), and/or
1243 a firewall. If the hostname is localhost, <application>Privoxy</application>
1244 will explicitly try to bind to an IPv4 address. For other hostnames it depends
1245 on the operating system which IP version will be used.
1248 If you open <application>Privoxy</application> to untrusted users, you will
1249 also want to make sure that the following actions are disabled: <literal><link
1250 linkend="enable-edit-actions">enable-edit-actions</link></literal> and
1251 <literal><link linkend="enable-remote-toggle">enable-remote-toggle</link></literal>
1256 <term>Example:</term>
1259 Suppose you are running <application>Privoxy</application> on
1260 a machine which has the address 192.168.0.1 on your local private network
1261 (192.168.0.0) and has another outside connection with a different address.
1262 You want it to serve requests from inside only:
1266 listen-address 192.168.0.1:8118
1270 Suppose you are running <application>Privoxy</application> on an
1271 IPv6-capable machine and you want it to listen on the IPv6 address
1272 of the loopback device:
1276 listen-address [::1]:8118
1283 <![%config-file;[<literallayout>@@listen-address 127.0.0.1:8118</literallayout>]]>
1287 <!-- ~~~~~ New section ~~~~~ -->
1288 <sect3 renderas="sect4" id="toggle"><title>toggle</title>
1292 <term>Specifies:</term>
1295 Initial state of "toggle" status
1300 <term>Type of value:</term>
1306 <term>Default value:</term>
1312 <term>Effect if unset:</term>
1315 Act as if toggled on
1323 If set to 0, <application>Privoxy</application> will start in
1324 <quote>toggled off</quote> mode, i.e. mostly behave like a normal,
1325 content-neutral proxy with both ad blocking and content filtering
1326 disabled. See <literal>enable-remote-toggle</literal> below.
1328 This is not really useful
1329 anymore, since toggling is much easier via <ulink
1330 url="http://config.privoxy.org/toggle">the web interface</ulink> than via
1331 editing the <filename>conf</filename> file.
1333 Remote toggling is now disabled by default. fk 2007-11-07)
1337 The windows version will only display the toggle icon in the system tray
1338 if this option is present.
1344 <![%config-file;[<literallayout>@@toggle 1</literallayout>]]>
1348 <!-- ~~~~~ New section ~~~~~ -->
1349 <sect3 renderas="sect4" id="enable-remote-toggle"><title>enable-remote-toggle</title>
1352 <term>Specifies:</term>
1355 Whether or not the <ulink url="http://config.privoxy.org/toggle">web-based toggle
1356 feature</ulink> may be used
1361 <term>Type of value:</term>
1367 <term>Default value:</term>
1373 <term>Effect if unset:</term>
1376 The web-based toggle feature is disabled.
1384 When toggled off, <application>Privoxy</application> mostly acts like a normal,
1385 content-neutral proxy, i.e. doesn't block ads or filter content.
1388 Access to the toggle feature can <emphasis>not</emphasis> be
1389 controlled separately by <quote>ACLs</quote> or HTTP authentication,
1390 so that everybody who can access <application>Privoxy</application> (see
1391 <quote>ACLs</quote> and <literal>listen-address</literal> above) can
1392 toggle it for all users. So this option is <emphasis>not recommended</emphasis>
1393 for multi-user environments with untrusted users.
1396 Note that malicious client side code (e.g Java) is also
1397 capable of using this option.
1400 As a lot of <application>Privoxy</application> users don't read
1401 documentation, this feature is disabled by default.
1404 Note that you must have compiled <application>Privoxy</application> with
1405 support for this feature, otherwise this option has no effect.
1411 <![%config-file;[<literallayout>@@enable-remote-toggle 0</literallayout>]]>
1415 <!-- ~~~~~ New section ~~~~~ -->
1416 <sect3 renderas="sect4" id="enable-remote-http-toggle"><title>enable-remote-http-toggle</title>
1419 <term>Specifies:</term>
1422 Whether or not Privoxy recognizes special HTTP headers to change its behaviour.
1427 <term>Type of value:</term>
1433 <term>Default value:</term>
1439 <term>Effect if unset:</term>
1442 Privoxy ignores special HTTP headers.
1450 When toggled on, the client can change <application>Privoxy's</application>
1451 behaviour by setting special HTTP headers. Currently the only supported
1452 special header is <quote>X-Filter: No</quote>, to disable filtering for
1453 the ongoing request, even if it is enabled in one of the action files.
1456 This feature is disabled by default. If you are using
1457 <application>Privoxy</application> in a environment with trusted clients,
1458 you may enable this feature at your discretion. Note that malicious client
1459 side code (e.g Java) is also capable of using this feature.
1462 This option will be removed in future releases as it has been obsoleted
1463 by the more general header taggers.
1469 <![%config-file;[<literallayout>@@enable-remote-http-toggle 0</literallayout>]]>
1473 <!-- ~~~~~ New section ~~~~~ -->
1474 <sect3 renderas="sect4" id="enable-edit-actions"><title>enable-edit-actions</title>
1477 <term>Specifies:</term>
1480 Whether or not the <ulink url="http://config.privoxy.org/show-status">web-based actions
1481 file editor</ulink> may be used
1486 <term>Type of value:</term>
1492 <term>Default value:</term>
1498 <term>Effect if unset:</term>
1501 The web-based actions file editor is disabled.
1509 Access to the editor can <emphasis>not</emphasis> be
1510 controlled separately by <quote>ACLs</quote> or HTTP authentication,
1511 so that everybody who can access <application>Privoxy</application> (see
1512 <quote>ACLs</quote> and <literal>listen-address</literal> above) can
1513 modify its configuration for all users.
1516 This option is <emphasis>not recommended</emphasis> for environments
1517 with untrusted users and as a lot of <application>Privoxy</application>
1518 users don't read documentation, this feature is disabled by default.
1521 Note that malicious client side code (e.g Java) is also
1522 capable of using the actions editor and you shouldn't enable
1523 this options unless you understand the consequences and are
1524 sure your browser is configured correctly.
1527 Note that you must have compiled <application>Privoxy</application> with
1528 support for this feature, otherwise this option has no effect.
1534 <![%config-file;[<literallayout>@@enable-edit-actions 0</literallayout>]]>
1538 <sect3 renderas="sect4" id="enforce-blocks"><title>enforce-blocks</title>
1541 <term>Specifies:</term>
1544 Whether the user is allowed to ignore blocks and can <quote>go there anyway</quote>.
1549 <term>Type of value:</term>
1552 <replaceable>0 or 1</replaceable>
1557 <term>Default value:</term>
1559 <para><emphasis>0</emphasis></para>
1563 <term>Effect if unset:</term>
1566 Blocks are not enforced.
1574 <application>Privoxy</application> is mainly used to block and filter
1575 requests as a service to the user, for example to block ads and other
1576 junk that clogs the pipes. <application>Privoxy's</application> configuration
1577 isn't perfect and sometimes innocent pages are blocked. In this situation it
1578 makes sense to allow the user to enforce the request and have
1579 <application>Privoxy</application> ignore the block.
1582 In the default configuration <application>Privoxy's</application>
1583 <quote>Blocked</quote> page contains a <quote>go there anyway</quote>
1584 link to adds a special string (the force prefix) to the request URL.
1585 If that link is used, <application>Privoxy</application> will
1586 detect the force prefix, remove it again and let the request pass.
1589 Of course <application>Privoxy</application> can also be used to enforce
1590 a network policy. In that case the user obviously should not be able to
1591 bypass any blocks, and that's what the <quote>enforce-blocks</quote>
1592 option is for. If it's enabled, <application>Privoxy</application> hides
1593 the <quote>go there anyway</quote> link. If the user adds the force
1594 prefix by hand, it will not be accepted and the circumvention attempt
1600 <term>Examples:</term>
1608 <![%config-file;[<literallayout>@@enforce-blocks 0</literallayout>]]>
1612 <!-- ~~~~~ New section ~~~~~ -->
1613 <sect3 renderas="sect4" id="acls"><title>
1614 ACLs: permit-access and deny-access</title>
1615 <anchor id="permit-access">
1616 <anchor id="deny-access">
1620 <term>Specifies:</term>
1623 Who can access what.
1628 <term>Type of value:</term>
1631 <replaceable class="parameter">src_addr</replaceable>[:<replaceable class="parameter">port</replaceable>][/<replaceable class="parameter">src_masklen</replaceable>]
1632 [<replaceable class="parameter">dst_addr</replaceable>[:<replaceable class="parameter">port</replaceable>][/<replaceable class="parameter">dst_masklen</replaceable>]]
1635 Where <replaceable class="parameter">src_addr</replaceable> and
1636 <replaceable class="parameter">dst_addr</replaceable> are IPv4 addresses in dotted decimal notation or valid
1637 DNS names, <replaceable class="parameter">port</replaceable> is a port
1638 number, and <replaceable class="parameter">src_masklen</replaceable> and
1639 <replaceable class="parameter">dst_masklen</replaceable> are subnet masks in CIDR notation, i.e. integer
1640 values from 2 to 30 representing the length (in bits) of the network address. The masks and the whole
1641 destination part are optional.
1644 If your system implements
1645 <ulink url="http://tools.ietf.org/html/rfc3493">RFC 3493</ulink>, then
1646 <replaceable class="parameter">src_addr</replaceable> and <replaceable
1647 class="parameter">dst_addr</replaceable> can be IPv6 addresses delimeted by
1648 brackets, <replaceable class="parameter">port</replaceable> can be a number
1649 or a service name, and
1650 <replaceable class="parameter">src_masklen</replaceable> and
1651 <replaceable class="parameter">dst_masklen</replaceable> can be a number
1657 <term>Default value:</term>
1659 <para><emphasis>Unset</emphasis></para>
1661 If no <replaceable class="parameter">port</replaceable> is specified,
1662 any port will match. If no <replaceable class="parameter">src_masklen</replaceable> or
1663 <replaceable class="parameter">src_masklen</replaceable> is given, the complete IP
1664 address has to match (i.e. 32 bits for IPv4 and 128 bits for IPv6).
1669 <term>Effect if unset:</term>
1672 Don't restrict access further than implied by <literal>listen-address</literal>
1680 Access controls are included at the request of ISPs and systems
1681 administrators, and <emphasis>are not usually needed by individual users</emphasis>.
1682 For a typical home user, it will normally suffice to ensure that
1683 <application>Privoxy</application> only listens on the localhost
1684 (127.0.0.1) or internal (home) network address by means of the
1685 <link linkend="listen-address"><emphasis>listen-address</emphasis></link>
1689 Please see the warnings in the FAQ that <application>Privoxy</application>
1690 is not intended to be a substitute for a firewall or to encourage anyone
1691 to defer addressing basic security weaknesses.
1694 Multiple ACL lines are OK.
1695 If any ACLs are specified, <application>Privoxy</application> only talks
1696 to IP addresses that match at least one <literal>permit-access</literal> line
1697 and don't match any subsequent <literal>deny-access</literal> line. In other words, the
1698 last match wins, with the default being <literal>deny-access</literal>.
1701 If <application>Privoxy</application> is using a forwarder (see <literal>forward</literal> below)
1702 for a particular destination URL, the <replaceable class="parameter">dst_addr</replaceable>
1703 that is examined is the address of the forwarder and <emphasis>NOT</emphasis> the address
1704 of the ultimate target. This is necessary because it may be impossible for the local
1705 <application>Privoxy</application> to determine the IP address of the
1706 ultimate target (that's often what gateways are used for).
1709 You should prefer using IP addresses over DNS names, because the address lookups take
1710 time. All DNS names must resolve! You can <emphasis>not</emphasis> use domain patterns
1711 like <quote>*.org</quote> or partial domain names. If a DNS name resolves to multiple
1712 IP addresses, only the first one is used.
1715 Some systems allows IPv4 client to connect to IPv6 server socket.
1716 Then the client's IPv4 address will be translated by system into
1717 IPv6 address space with special prefix ::ffff:0:0/96 (so called IPv4
1718 mapped IPv6 address). <application>Privoxy</application> can handle it
1719 and maps such ACL addresses automatically.
1722 Denying access to particular sites by ACL may have undesired side effects
1723 if the site in question is hosted on a machine which also hosts other sites
1729 <term>Examples:</term>
1732 Explicitly define the default behavior if no ACL and
1733 <literal>listen-address</literal> are set: <quote>localhost</quote>
1734 is OK. The absence of a <replaceable class="parameter">dst_addr</replaceable> implies that
1735 <emphasis>all</emphasis> destination addresses are OK:
1739 permit-access localhost
1743 Allow any host on the same class C subnet as www.privoxy.org access to
1744 nothing but www.example.com (or other domains hosted on the same system):
1748 permit-access www.privoxy.org/24 www.example.com/32
1752 Allow access from any host on the 26-bit subnet 192.168.45.64 to anywhere,
1753 with the exception that 192.168.45.73 may not access the IP address behind
1754 www.dirty-stuff.example.com:
1758 permit-access 192.168.45.64/26
1759 deny-access 192.168.45.73 www.dirty-stuff.example.com
1763 Allow access from the IPv4 network 192.0.2.0/24 even if listening on
1764 an IPv6 wild card address (not supported on all platforms):
1768 permit-access 192.0.2.0/24
1772 This is equivalent to the following line even if listening on an
1773 IPv4 address (not supported on all platforms):
1777 permit-access [::ffff:192.0.2.0]/120
1786 <!-- ~~~~~ New section ~~~~~ -->
1787 <sect3 renderas="sect4" id="buffer-limit"><title>buffer-limit</title>
1791 <term>Specifies:</term>
1794 Maximum size of the buffer for content filtering.
1799 <term>Type of value:</term>
1801 <para>Size in Kbytes</para>
1805 <term>Default value:</term>
1811 <term>Effect if unset:</term>
1814 Use a 4MB (4096 KB) limit.
1822 For content filtering, i.e. the <literal>+filter</literal> and
1823 <literal>+deanimate-gif</literal> actions, it is necessary that
1824 <application>Privoxy</application> buffers the entire document body.
1825 This can be potentially dangerous, since a server could just keep sending
1826 data indefinitely and wait for your RAM to exhaust -- with nasty consequences.
1830 When a document buffer size reaches the <literal>buffer-limit</literal>, it is
1831 flushed to the client unfiltered and no further attempt to
1832 filter the rest of the document is made. Remember that there may be multiple threads
1833 running, which might require up to <literal>buffer-limit</literal> Kbytes
1834 <emphasis>each</emphasis>, unless you have enabled <quote>single-threaded</quote>
1841 <![%config-file;[<literallayout>@@buffer-limit 4096</literallayout>]]>
1846 <!-- ~ End section ~ -->
1849 <!-- ~~~~~ New section ~~~~~ -->
1851 <sect2 id="forwarding">
1852 <title>Forwarding</title>
1855 This feature allows routing of HTTP requests through a chain of
1859 Forwarding can be used to chain Privoxy with a caching proxy to speed
1860 up browsing. Using a parent proxy may also be necessary if the machine
1861 that <application>Privoxy</application> runs on has no direct Internet access.
1864 Note that parent proxies can severely decrease your privacy level.
1865 For example a parent proxy could add your IP address to the request
1866 headers and if it's a caching proxy it may add the <quote>Etag</quote>
1867 header to revalidation requests again, even though you configured Privoxy
1868 to remove it. It may also ignore Privoxy's header time randomization and use the
1869 original values which could be used by the server as cookie replacement
1870 to track your steps between visits.
1874 Also specified here are SOCKS proxies. <application>Privoxy</application>
1875 supports the SOCKS 4 and SOCKS 4A protocols.
1878 <sect3 renderas="sect4" id="forward"><title>forward</title>
1881 <term>Specifies:</term>
1884 To which parent HTTP proxy specific requests should be routed.
1889 <term>Type of value:</term>
1892 <replaceable class="parameter">target_pattern</replaceable>
1893 <replaceable class="parameter">http_parent</replaceable>[:<replaceable class="parameter">port</replaceable>]
1896 where <replaceable class="parameter">target_pattern</replaceable> is a <link linkend="af-patterns">URL pattern</link>
1897 that specifies to which requests (i.e. URLs) this forward rule shall apply. Use <literal>/</literal> to
1898 denote <quote>all URLs</quote>.
1899 <replaceable class="parameter">http_parent</replaceable>[:<replaceable class="parameter">port</replaceable>]
1900 is the DNS name or IP address of the parent HTTP proxy through which the requests should be forwarded,
1901 optionally followed by its listening port (default: 8000).
1902 Use a single dot (<literal>.</literal>) to denote <quote>no forwarding</quote>.
1907 <term>Default value:</term>
1909 <para><emphasis>Unset</emphasis></para>
1913 <term>Effect if unset:</term>
1916 Don't use parent HTTP proxies.
1924 If <replaceable class="parameter">http_parent</replaceable> is <quote>.</quote>, then requests are not
1925 forwarded to another HTTP proxy but are made directly to the web servers.
1928 <replaceable class="parameter">http_parent</replaceable> can be a
1929 numerical IPv6 address (if
1930 <ulink url="http://tools.ietf.org/html/rfc3493">RFC 3493</ulink> is
1931 implemented). To prevent clashes with the port delimiter, the whole IP
1932 address has to be put into brackets. On the other hand a <replaceable
1933 class="parameter">target_pattern</replaceable> containing an IPv6 address
1934 has to be put into angle brackets (normal brackets are reserved for
1935 regular expressions already).
1938 Multiple lines are OK, they are checked in sequence, and the last match wins.
1943 <term>Examples:</term>
1946 Everything goes to an example parent proxy, except SSL on port 443 (which it doesn't handle):
1950 forward / parent-proxy.example.org:8080
1955 Everything goes to our example ISP's caching proxy, except for requests
1956 to that ISP's sites:
1960 forward / caching-proxy.isp.example.net:8000
1961 forward .isp.example.net .
1965 Parent proxy specified by an IPv6 address:
1969 foward / [2001:DB8::1]:8000
1973 Suppose your parent proxy doesn't support IPv6:
1977 forward / parent-proxy.example.org:8000
1978 forward ipv6-server.example.org .
1979 forward <[2-3][0-9a-f][0-9a-f][0-9a-f]:*> .
1988 <!-- ~~~~~ New section ~~~~~ -->
1989 <sect3 renderas="sect4" id="socks"><title>
1990 forward-socks4, forward-socks4a and forward-socks5</title>
1991 <anchor id="forward-socks4">
1992 <anchor id="forward-socks4a">
1996 <term>Specifies:</term>
1999 Through which SOCKS proxy (and optionally to which parent HTTP proxy) specific requests should be routed.
2004 <term>Type of value:</term>
2007 <replaceable class="parameter">target_pattern</replaceable>
2008 <replaceable class="parameter">socks_proxy</replaceable>[:<replaceable class="parameter">port</replaceable>]
2009 <replaceable class="parameter">http_parent</replaceable>[:<replaceable class="parameter">port</replaceable>]
2012 where <replaceable class="parameter">target_pattern</replaceable> is a
2013 <link linkend="af-patterns">URL pattern</link> that specifies to which
2014 requests (i.e. URLs) this forward rule shall apply. Use <literal>/</literal> to
2015 denote <quote>all URLs</quote>. <replaceable class="parameter">http_parent</replaceable>
2016 and <replaceable class="parameter">socks_proxy</replaceable>
2017 are IP addresses in dotted decimal notation or valid DNS names
2018 (<replaceable class="parameter">http_parent</replaceable>
2019 may be <quote>.</quote> to denote <quote>no HTTP forwarding</quote>), and the optional
2020 <replaceable class="parameter">port</replaceable> parameters are TCP ports,
2021 i.e. integer values from 1 to 65535
2026 <term>Default value:</term>
2028 <para><emphasis>Unset</emphasis></para>
2032 <term>Effect if unset:</term>
2035 Don't use SOCKS proxies.
2043 Multiple lines are OK, they are checked in sequence, and the last match wins.
2046 The difference between <literal>forward-socks4</literal> and <literal>forward-socks4a</literal>
2047 is that in the SOCKS 4A protocol, the DNS resolution of the target hostname happens on the SOCKS
2048 server, while in SOCKS 4 it happens locally.
2051 With <literal>forward-socks5</literal> the DNS resolution will happen on the remote server as well.
2054 <replaceable class="parameter">socks_proxy</replaceable> and
2055 <replaceable class="parameter">http_parent</replaceable> can be a
2056 numerical IPv6 address (if
2057 <ulink url="http://tools.ietf.org/html/rfc3493">RFC 3493</ulink> is
2058 implemented). To prevent clashes with the port delimiter, the whole IP
2059 address has to be put into brackets. On the other hand a <replaceable
2060 class="parameter">target_pattern</replaceable> containing an IPv6 address
2061 has to be put into angle brackets (normal brackets are reserved for
2062 regular expressions already).
2065 If <replaceable class="parameter">http_parent</replaceable> is <quote>.</quote>, then requests are not
2066 forwarded to another HTTP proxy but are made (HTTP-wise) directly to the web servers, albeit through
2072 <term>Examples:</term>
2075 From the company example.com, direct connections are made to all
2076 <quote>internal</quote> domains, but everything outbound goes through
2077 their ISP's proxy by way of example.com's corporate SOCKS 4A gateway to
2082 forward-socks4a / socks-gw.example.com:1080 www-cache.isp.example.net:8080
2083 forward .example.com .
2087 A rule that uses a SOCKS 4 gateway for all destinations but no HTTP parent looks like this:
2091 forward-socks4 / socks-gw.example.com:1080 .
2096 To chain Privoxy and Tor, both running on the same system, you would use
2101 forward-socks5 / 127.0.0.1:9050 .
2106 The public <application>Tor</application> network can't be used to
2107 reach your local network, if you need to access local servers you
2108 therefore might want to make some exceptions:
2112 forward 192.168.*.*/ .
2114 forward 127.*.*.*/ .
2118 Unencrypted connections to systems in these address ranges will
2119 be as (un)secure as the local network is, but the alternative is that you
2120 can't reach the local network through <application>Privoxy</application>
2121 at all. Of course this may actually be desired and there is no reason
2122 to make these exceptions if you aren't sure you need them.
2125 If you also want to be able to reach servers in your local network by
2126 using their names, you will need additional exceptions that look like
2131 forward localhost/ .
2140 <![%user-man;[ <!-- not included in config due to length -->
2141 <!-- ~~~~~ New section ~~~~~ -->
2142 <sect3 renderas="sect4" id="advanced-forwarding-examples"><title>Advanced Forwarding Examples</title>
2145 If you have links to multiple ISPs that provide various special content
2146 only to their subscribers, you can configure multiple <application>Privoxies</application>
2147 which have connections to the respective ISPs to act as forwarders to each other, so that
2148 <emphasis>your</emphasis> users can see the internal content of all ISPs.
2152 Assume that host-a has a PPP connection to isp-a.example.net. And host-b has a PPP connection to
2153 isp-b.example.org. Both run <application>Privoxy</application>. Their forwarding
2154 configuration can look like this:
2164 forward .isp-b.example.net host-b:8118
2175 forward .isp-a.example.org host-a:8118
2180 Now, your users can set their browser's proxy to use either
2181 host-a or host-b and be able to browse the internal content
2182 of both isp-a and isp-b.
2186 If you intend to chain <application>Privoxy</application> and
2187 <application>squid</application> locally, then chaining as
2188 <literal>browser -> squid -> privoxy</literal> is the recommended way.
2192 Assuming that <application>Privoxy</application> and <application>squid</application>
2193 run on the same box, your <application>squid</application> configuration could then look like this:
2198 # Define Privoxy as parent proxy (without ICP)
2199 cache_peer 127.0.0.1 parent 8118 7 no-query
2201 # Define ACL for protocol FTP
2204 # Do not forward FTP requests to Privoxy
2205 always_direct allow ftp
2207 # Forward all the rest to Privoxy
2208 never_direct allow all</screen>
2212 You would then need to change your browser's proxy settings to <application>squid</application>'s address and port.
2213 Squid normally uses port 3128. If unsure consult <literal>http_port</literal> in <filename>squid.conf</filename>.
2217 You could just as well decide to only forward requests you suspect
2218 of leading to Windows executables through a virus-scanning parent proxy,
2219 say, on <literal>antivir.example.com</literal>, port 8010:
2225 forward /.*\.(exe|com|dll|zip)$ antivir.example.com:8010</screen>
2231 <sect3 renderas="sect4" id="forwarded-connect-retries"><title>forwarded-connect-retries</title>
2234 <term>Specifies:</term>
2237 How often Privoxy retries if a forwarded connection request fails.
2242 <term>Type of value:</term>
2245 <replaceable class="parameter">Number of retries.</replaceable>
2250 <term>Default value:</term>
2252 <para><emphasis>0</emphasis></para>
2256 <term>Effect if unset:</term>
2259 Connections forwarded through other proxies are treated like direct connections and no retry attempts are made.
2267 <replaceable class="parameter">forwarded-connect-retries</replaceable> is mainly interesting
2268 for socks4a connections, where <application>Privoxy</application> can't detect why the connections failed.
2269 The connection might have failed because of a DNS timeout in which case a retry makes sense,
2270 but it might also have failed because the server doesn't exist or isn't reachable. In this
2271 case the retry will just delay the appearance of Privoxy's error message.
2274 Note that in the context of this option, <quote>forwarded connections</quote> includes all connections
2275 that Privoxy forwards through other proxies. This option is not limited to the HTTP CONNECT method.
2278 Only use this option, if you are getting lots of forwarding-related error messages
2279 that go away when you try again manually. Start with a small value and check Privoxy's
2280 logfile from time to time, to see how many retries are usually needed.
2285 <term>Examples:</term>
2288 forwarded-connect-retries 1
2293 <![%config-file;[<literallayout>@@forwarded-connect-retries 0</literallayout>]]>
2299 <title>Miscellaneous</title>
2301 <sect3 renderas="sect4" id="accept-intercepted-requests"><title>accept-intercepted-requests</title>
2304 <term>Specifies:</term>
2307 Whether intercepted requests should be treated as valid.
2312 <term>Type of value:</term>
2315 <replaceable>0 or 1</replaceable>
2320 <term>Default value:</term>
2322 <para><emphasis>0</emphasis></para>
2326 <term>Effect if unset:</term>
2329 Only proxy requests are accepted, intercepted requests are treated as invalid.
2337 If you don't trust your clients and want to force them
2338 to use <application>Privoxy</application>, enable this
2339 option and configure your packet filter to redirect outgoing
2340 HTTP connections into <application>Privoxy</application>.
2343 Make sure that <application>Privoxy's</application> own requests
2344 aren't redirected as well. Additionally take care that
2345 <application>Privoxy</application> can't intentionally connect
2346 to itself, otherwise you could run into redirection loops if
2347 <application>Privoxy's</application> listening port is reachable
2348 by the outside or an attacker has access to the pages you visit.
2353 <term>Examples:</term>
2356 accept-intercepted-requests 1
2361 <![%config-file;[<literallayout>@@accept-intercepted-requests 0</literallayout>]]>
2364 <sect3 renderas="sect4" id="allow-cgi-request-crunching"><title>allow-cgi-request-crunching</title>
2367 <term>Specifies:</term>
2370 Whether requests to <application>Privoxy's</application> CGI pages can be blocked or redirected.
2375 <term>Type of value:</term>
2378 <replaceable>0 or 1</replaceable>
2383 <term>Default value:</term>
2385 <para><emphasis>0</emphasis></para>
2389 <term>Effect if unset:</term>
2392 <application>Privoxy</application> ignores block and redirect actions for its CGI pages.
2400 By default <application>Privoxy</application> ignores block or redirect actions
2401 for its CGI pages. Intercepting these requests can be useful in multi-user
2402 setups to implement fine-grained access control, but it can also render the complete
2403 web interface useless and make debugging problems painful if done without care.
2406 Don't enable this option unless you're sure that you really need it.
2411 <term>Examples:</term>
2414 allow-cgi-request-crunching 1
2419 <![%config-file;[<literallayout>@@allow-cgi-request-crunching 0</literallayout>]]>
2422 <sect3 renderas="sect4" id="split-large-forms"><title>split-large-forms</title>
2425 <term>Specifies:</term>
2428 Whether the CGI interface should stay compatible with broken HTTP clients.
2433 <term>Type of value:</term>
2436 <replaceable>0 or 1</replaceable>
2441 <term>Default value:</term>
2443 <para><emphasis>0</emphasis></para>
2447 <term>Effect if unset:</term>
2450 The CGI form generate long GET URLs.
2458 <application>Privoxy's</application> CGI forms can lead to
2459 rather long URLs. This isn't a problem as far as the HTTP
2460 standard is concerned, but it can confuse clients with arbitrary
2461 URL length limitations.
2464 Enabling split-large-forms causes <application>Privoxy</application>
2465 to divide big forms into smaller ones to keep the URL length down.
2466 It makes editing a lot less convenient and you can no longer
2467 submit all changes at once, but at least it works around this
2471 If you don't notice any editing problems, there is no reason
2472 to enable this option, but if one of the submit buttons appears
2473 to be broken, you should give it a try.
2478 <term>Examples:</term>
2486 <![%config-file;[<literallayout>@@split-large-forms 0</literallayout>]]>
2489 <sect3 renderas="sect4" id="keep-alive-timeout"><title>keep-alive-timeout</title>
2492 <term>Specifies:</term>
2495 Number of seconds after which an open connection will no longer be reused.
2500 <term>Type of value:</term>
2503 <replaceable>Time in seconds.</replaceable>
2508 <term>Default value:</term>
2514 <term>Effect if unset:</term>
2517 Connections are not kept alive.
2525 This option allows clients to keep the connection to &my-app;
2526 alive. If the server supports it, &my-app; will keep
2527 the connection to the server alive as well. Under certain
2528 circumstances this may result in speed-ups.
2531 By default, &my-app; will close the connection to the server if
2532 the client connection gets closed, or if the specified timeout
2533 has been reached without a new request coming in. This behaviour
2534 can be changed with the <ulink
2535 url="#CONNECTION-SHARING">connection-sharing</ulink> option.
2538 This option has no effect if <application>Privoxy</application>
2539 has been compiled without keep-alive support.
2544 <term>Examples:</term>
2547 keep-alive-timeout 300
2552 <![%config-file;[<literallayout>@@keep-alive-timeout 300</literallayout>]]>
2556 <sect3 renderas="sect4" id="default-server-timeout"><title>default-server-timeout</title>
2559 <term>Specifies:</term>
2562 Assumed server-side keep-alive timeout if not specified by the server.
2567 <term>Type of value:</term>
2570 <replaceable>Time in seconds.</replaceable>
2575 <term>Default value:</term>
2581 <term>Effect if unset:</term>
2584 Connections for which the server didn't specify the keep-alive
2585 timeout are not reused.
2593 Enabling this option significantly increases the number of connections
2594 that are reused, provided the <ulink
2595 url="#KEEP-ALIVE-TIMEOUT">keep-alive-timeout</ulink> option
2599 While it also increases the number of connections problems
2600 when &my-app; tries to reuse a connection that already has
2601 been closed on the server side, or is closed while &my-app;
2602 is trying to reuse it, this should only be a problem if it
2603 happens for the first request sent by the client. If it happens
2604 for requests on reused client connections, &my-app; will simply
2605 close the connection and the client is supposed to retry the
2606 request without bothering the user.
2609 Enabling this option is therefore only recommended if the
2611 url="#CONNECTION-SHARING">connection-sharing</ulink> option
2615 It is an error to specify a value larger than the <ulink
2616 url="#KEEP-ALIVE-TIMEOUT">keep-alive-timeout</ulink> value.
2619 This option has no effect if <application>Privoxy</application>
2620 has been compiled without keep-alive support.
2625 <term>Examples:</term>
2628 default-server-timeout 60
2633 <![%config-file;[<literallayout>@@#default-server-timeout 60</literallayout>]]>
2637 <sect3 renderas="sect4" id="connection-sharing"><title>connection-sharing</title>
2640 <term>Specifies:</term>
2643 Whether or not outgoing connections that have been kept alive
2644 should be shared between different incoming connections.
2649 <term>Type of value:</term>
2652 <replaceable>0 or 1</replaceable>
2657 <term>Default value:</term>
2663 <term>Effect if unset:</term>
2666 Connections are not shared.
2674 This option has no effect if <application>Privoxy</application>
2675 has been compiled without keep-alive support, or if it's disabled.
2683 Note that reusing connections doesn't necessary cause speedups.
2684 There are also a few privacy implications you should be aware of.
2687 If this option is effective, outgoing connections are shared between
2688 clients (if there are more than one) and closing the browser that initiated
2689 the outgoing connection does no longer affect the connection between &my-app;
2690 and the server unless the client's request hasn't been completed yet.
2693 If the outgoing connection is idle, it will not be closed until either
2694 <application>Privoxy's</application> or the server's timeout is reached.
2695 While it's open, the server knows that the system running &my-app; is still
2699 If there are more than one client (maybe even belonging to multiple users),
2700 they will be able to reuse each others connections. This is potentially
2701 dangerous in case of authentication schemes like NTLM where only the
2702 connection is authenticated, instead of requiring authentication for
2706 If there is only a single client, and if said client can keep connections
2707 alive on its own, enabling this option has next to no effect. If the client
2708 doesn't support connection keep-alive, enabling this option may make sense
2709 as it allows &my-app; to keep outgoing connections alive even if the client
2710 itself doesn't support it.
2713 You should also be aware that enabling this option increases the likelihood
2714 of getting the "No server or forwarder data" error message, especially if you
2715 are using a slow connection to the Internet.
2718 This option should only be used by experienced users who
2719 understand the risks and can weight them against the benefits.
2724 <term>Examples:</term>
2727 connection-sharing 1
2732 <![%config-file;[<literallayout>@@#connection-sharing 1</literallayout>]]>
2736 <sect3 renderas="sect4" id="socket-timeout"><title>socket-timeout</title>
2739 <term>Specifies:</term>
2742 Number of seconds after which a socket times out if
2743 no data is received.
2748 <term>Type of value:</term>
2751 <replaceable>Time in seconds.</replaceable>
2756 <term>Default value:</term>
2762 <term>Effect if unset:</term>
2765 A default value of 300 seconds is used.
2773 For SOCKS requests the timeout currently doesn't start until
2774 the SOCKS server accepted the request. This will be fixed in
2780 <term>Examples:</term>
2788 <![%config-file;[<literallayout>@@socket-timeout 300</literallayout>]]>
2792 <sect3 renderas="sect4" id="max-client-connections"><title>max-client-connections</title>
2795 <term>Specifies:</term>
2798 Maximum number of client connections that will be served.
2803 <term>Type of value:</term>
2806 <replaceable>Positive number.</replaceable>
2811 <term>Default value:</term>
2817 <term>Effect if unset:</term>
2820 Connections are served until a resource limit is reached.
2828 &my-app; creates one thread (or process) for every incoming client
2829 connection that isn't rejected based on the access control settings.
2832 If the system is powerful enough, &my-app; can theoretically deal with
2833 several hundred (or thousand) connections at the same time, but some
2834 operating systems enforce resource limits by shutting down offending
2835 processes and their default limits may be below the ones &my-app; would
2836 require under heavy load.
2839 Configuring &my-app; to enforce a connection limit below the thread
2840 or process limit used by the operating system makes sure this doesn't
2841 happen. Simply increasing the operating system's limit would work too,
2842 but if &my-app; isn't the only application running on the system,
2843 you may actually want to limit the resources used by &my-app;.
2846 If &my-app; is only used by a single trusted user, limiting the
2847 number of client connections is probably unnecessary. If there
2848 are multiple possibly untrusted users you probably still want to
2849 additionally use a packet filter to limit the maximal number of
2850 incoming connections per client. Otherwise a malicious user could
2851 intentionally create a high number of connections to prevent other
2852 users from using &my-app;.
2855 Obviously using this option only makes sense if you choose a limit
2856 below the one enforced by the operating system.
2861 <term>Examples:</term>
2864 max-client-connections 256
2869 <![%config-file;[<literallayout>@@#max-client-connections 256</literallayout>]]>
2875 <!-- ~ End section ~ -->
2878 <!-- ~~~~~ New section ~~~~~ -->
2880 <sect2 id="windows-gui">
2881 <title>Windows GUI Options</title>
2883 <application>Privoxy</application> has a number of options specific to the
2884 Windows GUI interface:
2887 <anchor id="activity-animation">
2888 <![%config-file;[<para>@@</para>]]> <!-- for spacing -->
2890 If <quote>activity-animation</quote> is set to 1, the
2891 <application>Privoxy</application> icon will animate when
2892 <quote>Privoxy</quote> is active. To turn off, set to 0.
2895 <![%config-file;[<literallayout>@@#activity-animation 1</literallayout>]]>
2901 <emphasis>activity-animation 1</emphasis>
2908 <anchor id="log-messages">
2909 <![%config-file;[<para>@@</para>]]> <!-- for spacing -->
2911 If <quote>log-messages</quote> is set to 1,
2912 <application>Privoxy</application> will log messages to the console
2916 <![%config-file;[<literallayout>@@#log-messages 1</literallayout>]]>
2922 <emphasis>log-messages 1</emphasis>
2929 <anchor id="log-buffer-size">
2930 <![%config-file;[<para>@@</para>]]> <!-- for spacing -->
2932 If <quote>log-buffer-size</quote> is set to 1, the size of the log buffer,
2933 i.e. the amount of memory used for the log messages displayed in the
2934 console window, will be limited to <quote>log-max-lines</quote> (see below).
2938 Warning: Setting this to 0 will result in the buffer to grow infinitely and
2939 eat up all your memory!
2942 <![%config-file;[<literallayout>@@#log-buffer-size 1</literallayout>]]>
2948 <emphasis>log-buffer-size 1</emphasis>
2955 <anchor id="log-max-lines">
2956 <![%config-file;[<para>@@</para>]]> <!-- for spacing -->
2958 <application>log-max-lines</application> is the maximum number of lines held
2959 in the log buffer. See above.
2962 <![%config-file;[<literallayout>@@#log-max-lines 200</literallayout>]]>
2968 <emphasis>log-max-lines 200</emphasis>
2975 <anchor id="log-highlight-messages">
2976 <![%config-file;[<para>@@</para>]]> <!-- for spacing -->
2978 If <quote>log-highlight-messages</quote> is set to 1,
2979 <application>Privoxy</application> will highlight portions of the log
2980 messages with a bold-faced font:
2983 <![%config-file;[<literallayout>@@#log-highlight-messages 1</literallayout>]]>
2989 <emphasis>log-highlight-messages 1</emphasis>
2996 <anchor id="log-font-name">
2997 <![%config-file;[<para>@@</para>]]> <!-- for spacing -->
2999 The font used in the console window:
3002 <![%config-file;[<literallayout>@@#log-font-name Comic Sans MS</literallayout>]]>
3008 <emphasis>log-font-name Comic Sans MS</emphasis>
3015 <anchor id="log-font-size">
3016 <![%config-file;[<para>@@</para>]]> <!-- for spacing -->
3018 Font size used in the console window:
3021 <![%config-file;[<literallayout>@@#log-font-size 8</literallayout>]]>
3027 <emphasis>log-font-size 8</emphasis>
3034 <anchor id="show-on-task-bar">
3035 <![%config-file;[<para>@@</para>]]> <!-- for spacing -->
3037 <quote>show-on-task-bar</quote> controls whether or not
3038 <application>Privoxy</application> will appear as a button on the Task bar
3042 <![%config-file;[<literallayout>@@#show-on-task-bar 0</literallayout>]]>
3048 <emphasis>show-on-task-bar 0</emphasis>
3055 <anchor id="close-button-minimizes">
3056 <![%config-file;[<para>@@</para>]]> <!-- for spacing -->
3058 If <quote>close-button-minimizes</quote> is set to 1, the Windows close
3059 button will minimize <application>Privoxy</application> instead of closing
3060 the program (close with the exit option on the File menu).
3063 <![%config-file;[<literallayout>@@#close-button-minimizes 1</literallayout>]]>
3069 <emphasis>close-button-minimizes 1</emphasis>
3076 <anchor id="hide-console">
3077 <![%config-file;[<para>@@</para>]]> <!-- for spacing -->
3079 The <quote>hide-console</quote> option is specific to the MS-Win console
3080 version of <application>Privoxy</application>. If this option is used,
3081 <application>Privoxy</application> will disconnect from and hide the
3085 <![%config-file;[<literallayout>@@#hide-console</literallayout>]]>
3091 #<emphasis>hide-console</emphasis>
3101 <!-- end config content common to both outputs -->
3104 <!-- These are dummy anchors to keep the processor quiet -->
3105 <!-- when building config-file only (ie. they are used in u-m only) -->
3108 <anchor id="filter">
3109 <anchor id="filter-file">
3111 <anchor id="actions-file">
3112 <anchor id="af-patterns">
3116 <!-- eof p-config.sgml -->