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 2.127 2017/06/26 12:14:38 fabiankeil Exp $
8 Copyright (C) 2001-2017 Privoxy Developers https://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 By default, the main configuration file is named <filename>config</filename>,
54 with the exception of Windows, where it is named <filename>config.txt</filename>.
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 &p-version;
100 $Id: p-config.sgml,v 2.127 2017/06/26 12:14:38 fabiankeil Exp $
103 Copyright (C) 2001-2017 Privoxy Developers https://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 #
121 7. WINDOWS GUI OPTIONS #
123 ##################################################################
127 <literallayout>I. INTRODUCTION
128 =============== <!-- fuck this madness --></literallayout>
131 This file holds Privoxy's main configuration. Privoxy detects
132 configuration changes automatically, so you don't have to restart it
133 unless you want to load a different configuration file.
136 The configuration will be reloaded with the first request after the
137 change was done, this request itself will still use the old configuration,
138 though. In other words: it takes two requests before you see the result of
139 your changes. Requests that are dropped due to ACL don't trigger reloads.
142 When starting Privoxy on Unix systems, give the location of this
143 file as last argument. On Windows systems, Privoxy will look for
144 this file with the name 'config.txt' in the current working directory
145 of the Privoxy process.
149 <literallayout><!-- funky spacing -->
151 II. FORMAT OF THE CONFIGURATION FILE
152 ====================================</literallayout>
155 Configuration lines consist of an initial keyword followed by a list
156 of values, all separated by whitespace (any number of spaces or
160 actionsfile default.action
163 Indicates that the actionsfile is named 'default.action'.
166 The '#' indicates a comment. Any part of a line following a '#' is
167 ignored, except if the '#' is preceded by a '\'.
170 Thus, by placing a # at the start of an existing configuration line,
171 you can make it a comment and it will be treated as if it weren't there.
172 This is called "commenting out" an option and can be useful. Removing
173 the # again is called "uncommenting".
176 Note that commenting out an option and leaving it at its default
177 are two completely different things! Most options behave very
178 differently when unset. See the "Effect if unset" explanation
179 in each option's description for details.
182 Long lines can be continued on the next line by using a `\' as
188 <!-- ************************************************ -->
189 <!-- The following is common to both outputs (mostly) -->
190 <!-- ************************************************ -->
194 <!-- ~~~~~ New section ~~~~~ -->
195 <sect2 id="local-set-up">
196 <title>Local Set-up Documentation</title>
199 If you intend to operate <application>Privoxy</application> for more users
200 than just yourself, it might be a good idea to let them know how to reach
201 you, what you block and why you do that, your policies, etc.
205 <!-- ~~~~~ New section ~~~~~ -->
206 <sect3 renderas="sect4" id="user-manual"><title>user-manual</title>
209 <term>Specifies:</term>
212 Location of the <application>Privoxy</application> User Manual.
217 <term>Type of value:</term>
219 <para>A fully qualified URI</para>
223 <term>Default value:</term>
225 <para><emphasis>Unset</emphasis></para>
229 <term>Effect if unset:</term>
232 <ulink url="https://www.privoxy.org/user-manual/">https://www.privoxy.org/<replaceable class="parameter">version</replaceable>/user-manual/</ulink>
233 will be used, where <replaceable class="parameter">version</replaceable> is the <application>Privoxy</application> version.
241 The User Manual URI is the single best source of information on
242 <application>Privoxy</application>, and is used for help links from some
243 of the internal CGI pages. The manual itself is normally packaged with the
244 binary distributions, so you probably want to set this to a locally
252 Unix, in local filesystem (may not work with all browsers):
254 <screen> user-manual file:///usr/share/doc/privoxy-&p-version;/user-manual/</screen>
256 Windows, in local filesystem, <emphasis>must</emphasis> use forward slash notation:
258 <screen> user-manual file:/c:/some-dir/privoxy-&p-version;/user-manual/</screen>
260 Windows, UNC notation (with forward slashes):
262 <screen> user-manual file://///some-server/some-path/privoxy-&p-version;/user-manual/</screen>
265 The best all purpose solution is simply to put the full local
266 <literal>PATH</literal> to where the <citetitle>User Manual</citetitle> is
269 <screen> user-manual /usr/share/doc/privoxy/user-manual</screen>
271 The User Manual is then available to anyone with access to
272 <application>Privoxy</application>, by following the built-in URL:
273 <literal>http://config.privoxy.org/user-manual/</literal>
274 (or the shortcut: <literal>http://p.p/user-manual/</literal>).
277 If the documentation is not on the local system, it can be accessed
278 from a remote server, as:
280 <screen> user-manual http://example.com/privoxy/user-manual/</screen>
282 <!-- this gets hammered in conversion to config. Text repeated below. -->
285 If set, this option should be <emphasis>the first option in the config
286 file</emphasis>, because it is used while the config file is being read
299 If set, this option should be the first option in the config
300 file, because it is used while the config file is being read.
309 <![%config-file;[<literallayout>@@#user-manual https://www.privoxy.org/user-manual/</literallayout>]]>
313 <!-- ~~~~~ New section ~~~~~ -->
314 <sect3 renderas="sect4" id="trust-info-url"><title>trust-info-url</title>
318 <term>Specifies:</term>
321 A URL to be displayed in the error page that users will see if access to an untrusted page is denied.
326 <term>Type of value:</term>
332 <term>Default value:</term>
334 <para><emphasis>Unset</emphasis></para>
338 <term>Effect if unset:</term>
341 No links are displayed on the "untrusted" error page.
349 The value of this option only matters if the experimental trust mechanism has been
350 activated. (See <link linkend="trustfile"><emphasis>trustfile</emphasis></link> below.)
353 If you use the trust mechanism, it is a good idea to write up some on-line
354 documentation about your trust policy and to specify the URL(s) here.
355 Use multiple times for multiple URLs.
358 The URL(s) should be added to the trustfile as well, so users don't end up
359 locked out from the information on why they were locked out in the first place!
365 <![%config-file;[<literallayout>@@#trust-info-url http://www.example.com/why_we_block.html</literallayout>]]>
366 <![%config-file;[<literallayout>@@#trust-info-url http://www.example.com/what_we_allow.html</literallayout>]]>
370 <!-- ~~~~~ New section ~~~~~ -->
371 <sect3 renderas="sect4" id="admin-address"><title>admin-address</title>
375 <term>Specifies:</term>
378 An email address to reach the <application>Privoxy</application> administrator.
383 <term>Type of value:</term>
385 <para>Email address</para>
389 <term>Default value:</term>
391 <para><emphasis>Unset</emphasis></para>
395 <term>Effect if unset:</term>
398 No email address is displayed on error pages and the CGI user interface.
406 If both <literal>admin-address</literal> and <literal>proxy-info-url</literal>
407 are unset, the whole "Local Privoxy Support" box on all generated pages will
414 <![%config-file;[<literallayout>@@#admin-address privoxy-admin@example.com</literallayout>]]>
418 <!-- ~~~~~ New section ~~~~~ -->
419 <sect3 renderas="sect4" id="proxy-info-url"><title>proxy-info-url</title>
423 <term>Specifies:</term>
426 A URL to documentation about the local <application>Privoxy</application> setup,
427 configuration or policies.
432 <term>Type of value:</term>
438 <term>Default value:</term>
440 <para><emphasis>Unset</emphasis></para>
444 <term>Effect if unset:</term>
447 No link to local documentation is displayed on error pages and the CGI user interface.
455 If both <literal>admin-address</literal> and <literal>proxy-info-url</literal>
456 are unset, the whole "Local Privoxy Support" box on all generated pages will
460 This URL shouldn't be blocked ;-)
466 <![%config-file;[<literallayout>@@#proxy-info-url http://www.example.com/proxy-service.html</literallayout>]]>
470 <!-- ~ End section ~ -->
474 <!-- ~~~~~ New section ~~~~~ -->
476 <sect2 id="conf-log-loc">
477 <title>Configuration and Log File Locations</title>
480 <application>Privoxy</application> can (and normally does) use a number of
481 other files for additional configuration, help and logging.
482 This section of the configuration file tells <application>Privoxy</application>
483 where to find those other files.
487 The user running <application>Privoxy</application>, must have read
488 permission for all configuration files, and write permission to any files
489 that would be modified, such as log files and actions files.
493 <!-- ~~~~~ New section ~~~~~ -->
494 <sect3 renderas="sect4" id="confdir"><title>confdir</title>
498 <term>Specifies:</term>
500 <para>The directory where the other configuration files are located.</para>
504 <term>Type of value:</term>
506 <para>Path name</para>
510 <term>Default value:</term>
512 <para>/etc/privoxy (Unix) <emphasis>or</emphasis> <application>Privoxy</application> installation dir (Windows) </para>
516 <term>Effect if unset:</term>
518 <para><emphasis>Mandatory</emphasis></para>
525 No trailing <quote><literal>/</literal></quote>, please.
531 <![%config-file;[<literallayout>@@confdir .</literallayout>]]>
534 <!-- ~~~~~ New section ~~~~~ -->
535 <sect3 renderas="sect4" id="templdir"><title>templdir</title>
539 <term>Specifies:</term>
541 <para>An alternative directory where the templates are loaded from.</para>
545 <term>Type of value:</term>
547 <para>Path name</para>
551 <term>Default value:</term>
557 <term>Effect if unset:</term>
559 <para>The templates are assumed to be located in confdir/template.</para>
566 <application>Privoxy's</application> original templates are usually
567 overwritten with each update. Use this option to relocate customized
568 templates that should be kept. As template variables might change
569 between updates, you shouldn't expect templates to work with
570 <application>Privoxy</application> releases other than the one
571 they were part of, though.
577 <![%config-file;[<literallayout>@@#templdir .</literallayout>]]>
581 <!-- ~~~~~ New section ~~~~~ -->
582 <sect3 renderas="sect4" id="temporary-directory"><title>temporary-directory</title>
586 <term>Specifies:</term>
588 <para>A directory where Privoxy can create temporary files.</para>
592 <term>Type of value:</term>
594 <para>Path name</para>
598 <term>Default value:</term>
604 <term>Effect if unset:</term>
606 <para>No temporary files are created, external filters don't work.</para>
613 To execute <literal><ulink url="actions-file.html#EXTERNAL-FILTER">external filters</ulink></literal>,
614 <application>Privoxy</application> has to create temporary files.
615 This directive specifies the directory the temporary files should
619 It should be a directory only <application>Privoxy</application>
620 (and trusted users) can access.
626 <![%config-file;[<literallayout>@@#temporary-directory .</literallayout>]]>
630 <!-- ~~~~~ New section ~~~~~ -->
631 <sect3 renderas="sect4" id="logdir"><title>logdir</title>
635 <term>Specifies:</term>
638 The directory where all logging takes place
639 (i.e. where the <filename>logfile</filename> is located).
644 <term>Type of value:</term>
646 <para>Path name</para>
650 <term>Default value:</term>
652 <para>/var/log/privoxy (Unix) <emphasis>or</emphasis> <application>Privoxy</application> installation dir (Windows) </para>
656 <term>Effect if unset:</term>
658 <para><emphasis>Mandatory</emphasis></para>
665 No trailing <quote><literal>/</literal></quote>, please.
671 <![%config-file;[<literallayout>@@logdir .</literallayout>]]>
675 <!-- ~~~~~ New section ~~~~~ -->
676 <sect3 renderas="sect4" id="actionsfile"><title>
679 <anchor id="default.action">
680 <anchor id="standard.action">
681 <anchor id="user.action">
682 <!-- Note: slightly modified this section 04/28/02, hal. See NOTE. -->
685 <term>Specifies:</term>
688 The <link linkend="actions-file">actions file(s)</link> to use
693 <term>Type of value:</term>
695 <para>Complete file name, relative to <literal>confdir</literal></para>
699 <term>Default values:</term>
703 <msgtext><literallayout> match-all.action # Actions that are applied to all sites and maybe overruled later on.</literallayout></msgtext>
706 <msgtext><literallayout> default.action # Main actions file</literallayout></msgtext>
709 <msgtext><literallayout> user.action # User customizations</literallayout></msgtext>
715 <term>Effect if unset:</term>
718 No actions are taken at all. More or less neutral proxying.
726 Multiple <literal>actionsfile</literal> lines are permitted, and are in fact recommended!
729 The default values are <filename>default.action</filename>, which is the
730 <quote>main</quote> actions file maintained by the developers, and
731 <filename>user.action</filename>, where you can make your personal additions.
734 Actions files contain all the per site and per URL configuration for
735 ad blocking, cookie management, privacy considerations, etc.
741 <!-- NOTE: alternate markup to make a simpler list doesn't work due to -->
742 <!-- html -> text conversion, blah -->
743 <![%config-file;[<literallayout>@@actionsfile match-all.action # Actions that are applied to all sites and maybe overruled later on.</literallayout>]]>
744 <![%config-file;[<literallayout>@@actionsfile default.action # Main actions file</literallayout>]]>
746 XXX: Like user.filter, user.action should probably be commented out
747 by default as not all packages install it into the default directory.
750 <![%config-file;[<literallayout>@@actionsfile user.action # User customizations</literallayout>]]>
753 <!-- ~~~~~ New section ~~~~~ -->
754 <sect3 renderas="sect4" id="filterfile"><title>filterfile</title>
755 <anchor id="default.filter">
758 <term>Specifies:</term>
761 The <link linkend="filter-file">filter file(s)</link> to use
766 <term>Type of value:</term>
768 <para>File name, relative to <literal>confdir</literal></para>
772 <term>Default value:</term>
774 <para>default.filter (Unix) <emphasis>or</emphasis> default.filter.txt (Windows)</para>
778 <term>Effect if unset:</term>
781 No textual content filtering takes place, i.e. all
782 <literal>+<link linkend="filter">filter</link>{<replaceable class="parameter">name</replaceable>}</literal>
783 actions in the actions files are turned neutral.
791 Multiple <literal>filterfile</literal> lines are permitted.
794 The <link linkend="filter-file">filter files</link> contain content modification
795 rules that use <link linkend="regex">regular expressions</link>. These rules permit
796 powerful changes on the content of Web pages, and optionally the headers
797 as well, e.g., you could try to disable your favorite JavaScript annoyances,
798 re-write the actual displayed text, or just have some fun
799 playing buzzword bingo with web pages.
803 <literal>+<link linkend="filter">filter</link>{<replaceable class="parameter">name</replaceable>}</literal>
804 actions rely on the relevant filter (<replaceable class="parameter">name</replaceable>)
805 to be defined in a filter file!
808 A pre-defined filter file called <filename>default.filter</filename> that contains
809 a number of useful filters for common problems is included in the distribution.
810 See the section on the <literal><link linkend="filter">filter</link></literal>
814 It is recommended to place any locally adapted filters into a separate
815 file, such as <filename>user.filter</filename>.
821 <![%config-file;[<literallayout>@@filterfile default.filter</literallayout>]]>
822 <![%config-file;[<literallayout>@@filterfile user.filter # User customizations</literallayout>]]>
826 <!-- ~~~~~ New section ~~~~~ -->
827 <sect3 renderas="sect4" id="logfile"><title>logfile</title>
831 <term>Specifies:</term>
839 <term>Type of value:</term>
841 <para>File name, relative to <literal>logdir</literal></para>
845 <term>Default value:</term>
847 <para><emphasis>Unset (commented out)</emphasis>. When activated: logfile (Unix) <emphasis>or</emphasis> privoxy.log (Windows).</para>
851 <term>Effect if unset:</term>
854 No logfile is written.
862 The logfile is where all logging and error messages are written. The level
863 of detail and number of messages are set with the <literal>debug</literal>
864 option (see below). The logfile can be useful for tracking down a problem with
865 <application>Privoxy</application> (e.g., it's not blocking an ad you
866 think it should block) and it can help you to monitor what your browser
870 Depending on the debug options below, the logfile may be a privacy risk
871 if third parties can get access to it. As most users will never look
872 at it, <application>Privoxy</application> only logs fatal errors by default.
875 For most troubleshooting purposes, you will have to change that,
876 please refer to the debugging section for details.
879 Any log files must be writable by whatever user <application>Privoxy</application>
880 is being run as (on Unix, default user id is <quote>privoxy</quote>).
883 To prevent the logfile from growing indefinitely, it is recommended to
884 periodically rotate or shorten it. Many operating systems support log
885 rotation out of the box, some require additional software to do it.
886 For details, please refer to the documentation for your operating system.
892 <![%config-file;[<literallayout>@@logfile logfile</literallayout>]]>
896 <!-- ~~~~~ New section ~~~~~ -->
897 <sect3 renderas="sect4" id="trustfile"><title>trustfile</title>
900 <term>Specifies:</term>
903 The name of the trust file to use
908 <term>Type of value:</term>
910 <para>File name, relative to <literal>confdir</literal></para>
914 <term>Default value:</term>
916 <para><emphasis>Unset (commented out)</emphasis>. When activated: trust (Unix) <emphasis>or</emphasis> trust.txt (Windows)</para>
920 <term>Effect if unset:</term>
923 The entire trust mechanism is disabled.
931 The trust mechanism is an experimental feature for building white-lists and should
932 be used with care. It is <emphasis>NOT</emphasis> recommended for the casual user.
935 If you specify a trust file, <application>Privoxy</application> will only allow
936 access to sites that are specified in the trustfile. Sites can be listed
940 Prepending a <literal>~</literal> character limits access to this site
941 only (and any sub-paths within this site), e.g.
942 <literal>~www.example.com</literal> allows access to
943 <literal>~www.example.com/features/news.html</literal>, etc.
946 Or, you can designate sites as <emphasis>trusted referrers</emphasis>, by
947 prepending the name with a <literal>+</literal> character. The effect is that
948 access to untrusted sites will be granted -- but only if a link from this
949 trusted referrer was used to get there. The link target will then be added
950 to the <quote>trustfile</quote> so that future, direct accesses will be
951 granted. Sites added via this mechanism do not become trusted referrers
952 themselves (i.e. they are added with a <literal>~</literal> designation).
953 There is a limit of 512 such entries, after which new entries will not be
957 If you use the <literal>+</literal> operator in the trust file, it may grow
958 considerably over time.
961 It is recommended that <application>Privoxy</application> be compiled with
962 the <literal>--disable-force</literal>, <literal>--disable-toggle</literal> and
963 <literal> --disable-editor</literal> options, if this feature is to be
967 Possible applications include limiting Internet access for children.
974 <![%config-file;[<literallayout>@@#trustfile trust</literallayout>]]>
978 <!-- ~ End section ~ -->
980 <!-- ~~~~~ New section ~~~~~ -->
981 <sect2 id="debugging">
982 <title>Debugging</title>
985 These options are mainly useful when tracing a problem.
986 Note that you might also want to invoke
987 <application>Privoxy</application> with the <literal>--no-daemon</literal>
988 command line option when debugging.
991 <sect3 renderas="sect4" id="debug"><title>debug</title>
995 <term>Specifies:</term>
998 Key values that determine what information gets logged.
1003 <term>Type of value:</term>
1005 <para>Integer values</para>
1009 <term>Default value:</term>
1011 <para>0 (i.e.: only fatal errors (that cause Privoxy to exit) are logged)</para>
1015 <term>Effect if unset:</term>
1018 Default value is used (see above).
1026 The available debug levels are:
1029 debug 1 # Log the destination for each request &my-app; let through. See also debug 1024.
1030 debug 2 # show each connection status
1031 debug 4 # show I/O status
1032 debug 8 # show header parsing
1033 debug 16 # log all data written to the network
1034 debug 32 # debug force feature
1035 debug 64 # debug regular expression filters
1036 debug 128 # debug redirects
1037 debug 256 # debug GIF de-animation
1038 debug 512 # Common Log Format
1039 debug 1024 # Log the destination for requests &my-app; didn't let through, and the reason why.
1040 debug 2048 # CGI user interface
1041 debug 4096 # Startup banner and warnings.
1042 debug 8192 # Non-fatal errors
1043 debug 32768 # log all data read from the network
1044 debug 65536 # Log the applying actions
1047 To select multiple debug levels, you can either add them or use
1048 multiple <literal>debug</literal> lines.
1051 A debug level of 1 is informative because it will show you each request
1052 as it happens. <emphasis>1, 1024, 4096 and 8192 are recommended</emphasis>
1053 so that you will notice when things go wrong. The other levels are
1054 probably only of interest if you are hunting down a specific problem.
1055 They can produce a hell of an output (especially 16).
1058 If you are used to the more verbose settings, simply enable the debug lines
1062 If you want to use pure CLF (Common Log Format), you should set <quote>debug
1063 512</quote> <emphasis>ONLY</emphasis> and not enable anything else.
1066 <application>Privoxy</application> has a hard-coded limit for the
1067 length of log messages. If it's reached, messages are logged truncated
1068 and marked with <quote>... [too long, truncated]</quote>.
1071 Please don't file any support requests without trying to reproduce
1072 the problem with increased debug level first. Once you read the log
1073 messages, you may even be able to solve the problem on your own.
1079 <![%config-file;[<literallayout>@@#debug 1 # Log the destination for each request &my-app; let through.</literallayout>]]>
1080 <![%config-file;[<literallayout>@@#debug 1024 # Log the destination for requests &my-app; didn't let through, and the reason why.</literallayout>]]>
1081 <![%config-file;[<literallayout>@@#debug 4096 # Startup banner and warnings</literallayout>]]>
1082 <![%config-file;[<literallayout>@@#debug 8192 # Non-fatal errors</literallayout>]]>
1086 <!-- ~~~~~ New section ~~~~~ -->
1087 <sect3 renderas="sect4" id="single-threaded"><title>single-threaded</title>
1091 <term>Specifies:</term>
1094 Whether to run only one server thread.
1099 <term>Type of value:</term>
1101 <para><emphasis>1 or 0</emphasis></para>
1105 <term>Default value:</term>
1107 <para><emphasis>0</emphasis></para>
1111 <term>Effect if unset:</term>
1114 Multi-threaded (or, where unavailable: forked) operation, i.e. the ability to
1115 serve multiple requests simultaneously.
1123 This option is only there for debugging purposes.
1124 <emphasis>It will drastically reduce performance.</emphasis>
1130 <![%config-file;[<literallayout>@@#single-threaded 1</literallayout>]]>
1133 <!-- ~~~~~ New section ~~~~~ -->
1134 <sect3 renderas="sect4" id="hostname"><title>hostname</title>
1138 <term>Specifies:</term>
1141 The hostname shown on the CGI pages.
1146 <term>Type of value:</term>
1152 <term>Default value:</term>
1154 <para><emphasis>Unset</emphasis></para>
1158 <term>Effect if unset:</term>
1161 The hostname provided by the operating system is used.
1169 On some misconfigured systems resolving the hostname fails or
1170 takes too much time and slows Privoxy down. Setting a fixed hostname
1171 works around the problem.
1174 In other circumstances it might be desirable to show a hostname
1175 other than the one returned by the operating system. For example
1176 if the system has several different hostnames and you don't want
1177 to use the first one.
1180 Note that Privoxy does not validate the specified hostname value.
1186 <![%config-file;[<literallayout>@@#hostname hostname.example.org</literallayout>]]>
1191 <!-- ~ End section ~ -->
1194 <!-- ~~~~~ New section ~~~~~ -->
1195 <sect2 id="access-control">
1196 <title>Access Control and Security</title>
1199 This section of the config file controls the security-relevant aspects
1200 of <application>Privoxy</application>'s configuration.
1204 <!-- ~~~~~ New section ~~~~~ -->
1205 <sect3 renderas="sect4" id="listen-address"><title>listen-address</title>
1209 <term>Specifies:</term>
1212 The address and TCP port on which <application>Privoxy</application> will
1213 listen for client requests.
1218 <term>Type of value:</term>
1220 <para>[<replaceable class="parameter">IP-Address</replaceable>]:<replaceable class="parameter">Port</replaceable></para>
1221 <para>[<replaceable class="parameter">Hostname</replaceable>]:<replaceable class="parameter">Port</replaceable></para>
1226 <term>Default value:</term>
1228 <para>127.0.0.1:8118</para>
1232 <term>Effect if unset:</term>
1235 Bind to 127.0.0.1 (IPv4 localhost), port 8118. This is suitable and
1236 recommended for home users who run <application>Privoxy</application> on
1237 the same machine as their browser.
1245 You will need to configure your browser(s) to this proxy address and port.
1248 If you already have another service running on port 8118, or if you want to
1249 serve requests from other machines (e.g. on your local network) as well, you
1250 will need to override the default.
1253 You can use this statement multiple times to make
1254 <application>Privoxy</application> listen on more ports or more
1255 <abbrev>IP</abbrev> addresses. Suitable if your operating system does not
1256 support sharing <abbrev>IPv6</abbrev> and <abbrev>IPv4</abbrev> protocols
1260 If a hostname is used instead of an IP address, <application>Privoxy</application>
1261 will try to resolve it to an IP address and if there are multiple, use the first
1265 If the address for the hostname isn't already known on the system
1266 (for example because it's in /etc/hostname), this may result in DNS
1270 If the specified address isn't available on the system, or if the
1271 hostname can't be resolved, <application>Privoxy</application>
1275 IPv6 addresses containing colons have to be quoted by brackets.
1276 They can only be used if <application>Privoxy</application> has
1277 been compiled with IPv6 support. If you aren't sure if your version
1278 supports it, have a look at
1279 <literal>http://config.privoxy.org/show-status</literal>.
1282 Some operating systems will prefer IPv6 to IPv4 addresses even if the
1283 system has no IPv6 connectivity which is usually not expected by the user.
1284 Some even rely on DNS to resolve localhost which mean the "localhost" address
1285 used may not actually be local.
1288 It is therefore recommended to explicitly configure the intended IP address
1289 instead of relying on the operating system, unless there's a strong reason not to.
1292 If you leave out the address, <application>Privoxy</application> will bind to all
1293 IPv4 interfaces (addresses) on your machine and may become reachable from the
1294 Internet and/or the local network. Be aware that some GNU/Linux distributions
1295 modify that behaviour without updating the documentation. Check for non-standard
1296 patches if your <application>Privoxy</application> version behaves differently.
1299 If you configure <application>Privoxy</application> to be reachable from the
1300 network, consider using <link linkend="acls">access control lists</link>
1301 (ACL's, see below), and/or a firewall.
1304 If you open <application>Privoxy</application> to untrusted users, you will
1305 also want to make sure that the following actions are disabled: <literal><link
1306 linkend="enable-edit-actions">enable-edit-actions</link></literal> and
1307 <literal><link linkend="enable-remote-toggle">enable-remote-toggle</link></literal>
1312 <term>Example:</term>
1315 Suppose you are running <application>Privoxy</application> on
1316 a machine which has the address 192.168.0.1 on your local private network
1317 (192.168.0.0) and has another outside connection with a different address.
1318 You want it to serve requests from inside only:
1321 listen-address 192.168.0.1:8118
1324 Suppose you are running <application>Privoxy</application> on an
1325 IPv6-capable machine and you want it to listen on the IPv6 address
1326 of the loopback device:
1329 listen-address [::1]:8118
1335 <![%config-file;[<literallayout>@@listen-address 127.0.0.1:8118</literallayout>]]>
1339 <!-- ~~~~~ New section ~~~~~ -->
1340 <sect3 renderas="sect4" id="toggle"><title>toggle</title>
1344 <term>Specifies:</term>
1347 Initial state of "toggle" status
1352 <term>Type of value:</term>
1358 <term>Default value:</term>
1364 <term>Effect if unset:</term>
1367 Act as if toggled on
1375 If set to 0, <application>Privoxy</application> will start in
1376 <quote>toggled off</quote> mode, i.e. mostly behave like a normal,
1377 content-neutral proxy with both ad blocking and content filtering
1378 disabled. See <literal>enable-remote-toggle</literal> below.
1384 <![%config-file;[<literallayout>@@toggle 1</literallayout>]]>
1388 <!-- ~~~~~ New section ~~~~~ -->
1389 <sect3 renderas="sect4" id="enable-remote-toggle"><title>enable-remote-toggle</title>
1392 <term>Specifies:</term>
1395 Whether or not the <ulink url="http://config.privoxy.org/toggle">web-based toggle
1396 feature</ulink> may be used
1401 <term>Type of value:</term>
1407 <term>Default value:</term>
1413 <term>Effect if unset:</term>
1416 The web-based toggle feature is disabled.
1424 When toggled off, <application>Privoxy</application> mostly acts like a normal,
1425 content-neutral proxy, i.e. doesn't block ads or filter content.
1428 Access to the toggle feature can <emphasis>not</emphasis> be
1429 controlled separately by <quote>ACLs</quote> or HTTP authentication,
1430 so that everybody who can access <application>Privoxy</application> (see
1431 <quote>ACLs</quote> and <literal>listen-address</literal> above) can
1432 toggle it for all users. So this option is <emphasis>not recommended</emphasis>
1433 for multi-user environments with untrusted users.
1436 Note that malicious client side code (e.g Java) is also
1437 capable of using this option.
1440 As a lot of <application>Privoxy</application> users don't read
1441 documentation, this feature is disabled by default.
1444 Note that you must have compiled <application>Privoxy</application> with
1445 support for this feature, otherwise this option has no effect.
1451 <![%config-file;[<literallayout>@@enable-remote-toggle 0</literallayout>]]>
1455 <!-- ~~~~~ New section ~~~~~ -->
1456 <sect3 renderas="sect4" id="enable-remote-http-toggle"><title>enable-remote-http-toggle</title>
1459 <term>Specifies:</term>
1462 Whether or not Privoxy recognizes special HTTP headers to change its behaviour.
1467 <term>Type of value:</term>
1473 <term>Default value:</term>
1479 <term>Effect if unset:</term>
1482 Privoxy ignores special HTTP headers.
1490 When toggled on, the client can change <application>Privoxy's</application>
1491 behaviour by setting special HTTP headers. Currently the only supported
1492 special header is <quote>X-Filter: No</quote>, to disable filtering for
1493 the ongoing request, even if it is enabled in one of the action files.
1496 This feature is disabled by default. If you are using
1497 <application>Privoxy</application> in a environment with trusted clients,
1498 you may enable this feature at your discretion. Note that malicious client
1499 side code (e.g Java) is also capable of using this feature.
1502 This option will be removed in future releases as it has been obsoleted
1503 by the more general header taggers.
1509 <![%config-file;[<literallayout>@@enable-remote-http-toggle 0</literallayout>]]>
1513 <!-- ~~~~~ New section ~~~~~ -->
1514 <sect3 renderas="sect4" id="enable-edit-actions"><title>enable-edit-actions</title>
1517 <term>Specifies:</term>
1520 Whether or not the <ulink url="http://config.privoxy.org/show-status">web-based actions
1521 file editor</ulink> may be used
1526 <term>Type of value:</term>
1532 <term>Default value:</term>
1538 <term>Effect if unset:</term>
1541 The web-based actions file editor is disabled.
1549 Access to the editor can <emphasis>not</emphasis> be
1550 controlled separately by <quote>ACLs</quote> or HTTP authentication,
1551 so that everybody who can access <application>Privoxy</application> (see
1552 <quote>ACLs</quote> and <literal>listen-address</literal> above) can
1553 modify its configuration for all users.
1556 This option is <emphasis>not recommended</emphasis> for environments
1557 with untrusted users and as a lot of <application>Privoxy</application>
1558 users don't read documentation, this feature is disabled by default.
1561 Note that malicious client side code (e.g Java) is also
1562 capable of using the actions editor and you shouldn't enable
1563 this options unless you understand the consequences and are
1564 sure your browser is configured correctly.
1567 Note that you must have compiled <application>Privoxy</application> with
1568 support for this feature, otherwise this option has no effect.
1574 <![%config-file;[<literallayout>@@enable-edit-actions 0</literallayout>]]>
1578 <sect3 renderas="sect4" id="enforce-blocks"><title>enforce-blocks</title>
1581 <term>Specifies:</term>
1584 Whether the user is allowed to ignore blocks and can <quote>go there anyway</quote>.
1589 <term>Type of value:</term>
1592 <replaceable>0 or 1</replaceable>
1597 <term>Default value:</term>
1599 <para><emphasis>0</emphasis></para>
1603 <term>Effect if unset:</term>
1606 Blocks are not enforced.
1614 <application>Privoxy</application> is mainly used to block and filter
1615 requests as a service to the user, for example to block ads and other
1616 junk that clogs the pipes. <application>Privoxy's</application> configuration
1617 isn't perfect and sometimes innocent pages are blocked. In this situation it
1618 makes sense to allow the user to enforce the request and have
1619 <application>Privoxy</application> ignore the block.
1622 In the default configuration <application>Privoxy's</application>
1623 <quote>Blocked</quote> page contains a <quote>go there anyway</quote>
1624 link to adds a special string (the force prefix) to the request URL.
1625 If that link is used, <application>Privoxy</application> will
1626 detect the force prefix, remove it again and let the request pass.
1629 Of course <application>Privoxy</application> can also be used to enforce
1630 a network policy. In that case the user obviously should not be able to
1631 bypass any blocks, and that's what the <quote>enforce-blocks</quote>
1632 option is for. If it's enabled, <application>Privoxy</application> hides
1633 the <quote>go there anyway</quote> link. If the user adds the force
1634 prefix by hand, it will not be accepted and the circumvention attempt
1640 <term>Examples:</term>
1648 <![%config-file;[<literallayout>@@enforce-blocks 0</literallayout>]]>
1652 <!-- ~~~~~ New section ~~~~~ -->
1653 <sect3 renderas="sect4" id="acls"><title>
1654 ACLs: permit-access and deny-access</title>
1655 <anchor id="permit-access">
1656 <anchor id="deny-access">
1660 <term>Specifies:</term>
1663 Who can access what.
1668 <term>Type of value:</term>
1671 <replaceable class="parameter">src_addr</replaceable>[:<replaceable class="parameter">port</replaceable>][/<replaceable class="parameter">src_masklen</replaceable>]
1672 [<replaceable class="parameter">dst_addr</replaceable>[:<replaceable class="parameter">port</replaceable>][/<replaceable class="parameter">dst_masklen</replaceable>]]
1675 Where <replaceable class="parameter">src_addr</replaceable> and
1676 <replaceable class="parameter">dst_addr</replaceable> are IPv4 addresses in dotted decimal notation or valid
1677 DNS names, <replaceable class="parameter">port</replaceable> is a port
1678 number, and <replaceable class="parameter">src_masklen</replaceable> and
1679 <replaceable class="parameter">dst_masklen</replaceable> are subnet masks in CIDR notation, i.e. integer
1680 values from 2 to 30 representing the length (in bits) of the network address. The masks and the whole
1681 destination part are optional.
1684 If your system implements
1685 <ulink url="http://tools.ietf.org/html/rfc3493">RFC 3493</ulink>, then
1686 <replaceable class="parameter">src_addr</replaceable> and <replaceable
1687 class="parameter">dst_addr</replaceable> can be IPv6 addresses delimeted by
1688 brackets, <replaceable class="parameter">port</replaceable> can be a number
1689 or a service name, and
1690 <replaceable class="parameter">src_masklen</replaceable> and
1691 <replaceable class="parameter">dst_masklen</replaceable> can be a number
1697 <term>Default value:</term>
1699 <para><emphasis>Unset</emphasis></para>
1701 If no <replaceable class="parameter">port</replaceable> is specified,
1702 any port will match. If no <replaceable class="parameter">src_masklen</replaceable> or
1703 <replaceable class="parameter">src_masklen</replaceable> is given, the complete IP
1704 address has to match (i.e. 32 bits for IPv4 and 128 bits for IPv6).
1709 <term>Effect if unset:</term>
1712 Don't restrict access further than implied by <literal>listen-address</literal>
1720 Access controls are included at the request of ISPs and systems
1721 administrators, and <emphasis>are not usually needed by individual users</emphasis>.
1722 For a typical home user, it will normally suffice to ensure that
1723 <application>Privoxy</application> only listens on the localhost
1724 (127.0.0.1) or internal (home) network address by means of the
1725 <link linkend="listen-address"><emphasis>listen-address</emphasis></link>
1729 Please see the warnings in the FAQ that <application>Privoxy</application>
1730 is not intended to be a substitute for a firewall or to encourage anyone
1731 to defer addressing basic security weaknesses.
1734 Multiple ACL lines are OK.
1735 If any ACLs are specified, <application>Privoxy</application> only talks
1736 to IP addresses that match at least one <literal>permit-access</literal> line
1737 and don't match any subsequent <literal>deny-access</literal> line. In other words, the
1738 last match wins, with the default being <literal>deny-access</literal>.
1741 If <application>Privoxy</application> is using a forwarder (see <literal>forward</literal> below)
1742 for a particular destination URL, the <replaceable class="parameter">dst_addr</replaceable>
1743 that is examined is the address of the forwarder and <emphasis>NOT</emphasis> the address
1744 of the ultimate target. This is necessary because it may be impossible for the local
1745 <application>Privoxy</application> to determine the IP address of the
1746 ultimate target (that's often what gateways are used for).
1749 You should prefer using IP addresses over DNS names, because the address lookups take
1750 time. All DNS names must resolve! You can <emphasis>not</emphasis> use domain patterns
1751 like <quote>*.org</quote> or partial domain names. If a DNS name resolves to multiple
1752 IP addresses, only the first one is used.
1755 Some systems allow IPv4 clients to connect to IPv6 server sockets.
1756 Then the client's IPv4 address will be translated by the system into
1757 IPv6 address space with special prefix ::ffff:0:0/96 (so called IPv4
1758 mapped IPv6 address). <application>Privoxy</application> can handle it
1759 and maps such ACL addresses automatically.
1762 Denying access to particular sites by ACL may have undesired side effects
1763 if the site in question is hosted on a machine which also hosts other sites
1769 <term>Examples:</term>
1772 Explicitly define the default behavior if no ACL and
1773 <literal>listen-address</literal> are set: <quote>localhost</quote>
1774 is OK. The absence of a <replaceable class="parameter">dst_addr</replaceable> implies that
1775 <emphasis>all</emphasis> destination addresses are OK:
1778 permit-access localhost
1781 Allow any host on the same class C subnet as www.privoxy.org access to
1782 nothing but www.example.com (or other domains hosted on the same system):
1785 permit-access www.privoxy.org/24 www.example.com/32
1788 Allow access from any host on the 26-bit subnet 192.168.45.64 to anywhere,
1789 with the exception that 192.168.45.73 may not access the IP address behind
1790 www.dirty-stuff.example.com:
1793 permit-access 192.168.45.64/26
1794 deny-access 192.168.45.73 www.dirty-stuff.example.com
1797 Allow access from the IPv4 network 192.0.2.0/24 even if listening on
1798 an IPv6 wild card address (not supported on all platforms):
1801 permit-access 192.0.2.0/24
1804 This is equivalent to the following line even if listening on an
1805 IPv4 address (not supported on all platforms):
1808 permit-access [::ffff:192.0.2.0]/120
1816 <!-- ~~~~~ New section ~~~~~ -->
1817 <sect3 renderas="sect4" id="buffer-limit"><title>buffer-limit</title>
1821 <term>Specifies:</term>
1824 Maximum size of the buffer for content filtering.
1829 <term>Type of value:</term>
1831 <para>Size in Kbytes</para>
1835 <term>Default value:</term>
1841 <term>Effect if unset:</term>
1844 Use a 4MB (4096 KB) limit.
1852 For content filtering, i.e. the <literal>+filter</literal> and
1853 <literal>+deanimate-gif</literal> actions, it is necessary that
1854 <application>Privoxy</application> buffers the entire document body.
1855 This can be potentially dangerous, since a server could just keep sending
1856 data indefinitely and wait for your RAM to exhaust -- with nasty consequences.
1860 When a document buffer size reaches the <literal>buffer-limit</literal>, it is
1861 flushed to the client unfiltered and no further attempt to
1862 filter the rest of the document is made. Remember that there may be multiple threads
1863 running, which might require up to <literal>buffer-limit</literal> Kbytes
1864 <emphasis>each</emphasis>, unless you have enabled <quote>single-threaded</quote>
1871 <![%config-file;[<literallayout>@@buffer-limit 4096</literallayout>]]>
1874 <!-- ~~~~~ New section ~~~~~ -->
1875 <sect3 renderas="sect4" id="enable-proxy-authentication-forwarding"><title>enable-proxy-authentication-forwarding</title>
1878 <term>Specifies:</term>
1881 Whether or not proxy authentication through &my-app; should work.
1886 <term>Type of value:</term>
1892 <term>Default value:</term>
1898 <term>Effect if unset:</term>
1901 Proxy authentication headers are removed.
1909 Privoxy itself does not support proxy authentication, but can
1910 allow clients to authenticate against Privoxy's parent proxy.
1913 By default Privoxy (3.0.21 and later) don't do that and remove
1914 Proxy-Authorization headers in requests and Proxy-Authenticate
1915 headers in responses to make it harder for malicious sites to
1916 trick inexperienced users into providing login information.
1919 If this option is enabled the headers are forwarded.
1922 Enabling this option is <emphasis>not recommended</emphasis> if there is
1923 no parent proxy that requires authentication or if the local network between
1924 Privoxy and the parent proxy isn't trustworthy. If proxy authentication is
1925 only required for some requests, it is recommended to use a client header filter
1926 to remove the authentication headers for requests where they aren't needed.
1932 <![%config-file;[<literallayout>@@enable-proxy-authentication-forwarding 0</literallayout>]]>
1935 <!-- ~~~~~ New section ~~~~~ -->
1936 <sect3 renderas="sect4" id="trusted-cgi-referer"><title>trusted-cgi-referer</title>
1939 <term>Specifies:</term>
1942 A trusted website or webpage whose links can be followed to reach sensitive CGI pages
1947 <term>Type of value:</term>
1949 <para>URL or URL prefix</para>
1953 <term>Default value:</term>
1959 <term>Effect if unset:</term>
1962 No external pages are considered trusted referers.
1970 Before &my-app; accepts configuration changes through CGI pages like
1971 <link linkend="client-specific-tag">client-tags</link> or the
1972 <link linkend="enable-remote-toggle">remote toggle</link>, it checks
1973 the Referer header to see if the request comes from a trusted source.
1976 By default only the webinterface domains
1977 <ulink url="http://config.privoxy.org/">config.privoxy.org</ulink>
1979 <ulink url="http://p.p/">p.p</ulink>
1980 are considered trustworthy.
1981 Requests originating from other domains are rejected to prevent
1982 third-parties from modifiying Privoxy's state by e.g. embedding
1983 images that result in CGI requests.
1986 In some environments it may be desirable to embed links to CGI pages
1987 on external pages, for example on an Intranet homepage the Privoxy admin
1991 The <quote>trusted-cgi-referer</quote> option can be used to add that page,
1992 or the whole domain, as trusted source so the resulting requests aren't
1994 Requests are accepted if the specified trusted-cgi-refer is the prefix
1999 Declaring pages the admin doesn't control trustworthy may allow
2000 malicious third parties to modify Privoxy's internal state against
2001 the user's wishes and without the user's knowledge.
2008 <![%config-file;[<literallayout>@@trusted-cgi-referer http://www.example.org/local-privoxy-control-page</literallayout>]]>
2013 <!-- ~ End section ~ -->
2016 <!-- ~~~~~ New section ~~~~~ -->
2018 <sect2 id="forwarding">
2019 <title>Forwarding</title>
2022 This feature allows routing of HTTP requests through a chain of
2026 Forwarding can be used to chain Privoxy with a caching proxy to speed
2027 up browsing. Using a parent proxy may also be necessary if the machine
2028 that <application>Privoxy</application> runs on has no direct Internet access.
2031 Note that parent proxies can severely decrease your privacy level.
2032 For example a parent proxy could add your IP address to the request
2033 headers and if it's a caching proxy it may add the <quote>Etag</quote>
2034 header to revalidation requests again, even though you configured Privoxy
2035 to remove it. It may also ignore Privoxy's header time randomization and use the
2036 original values which could be used by the server as cookie replacement
2037 to track your steps between visits.
2041 Also specified here are SOCKS proxies. <application>Privoxy</application>
2042 supports the SOCKS 4 and SOCKS 4A protocols.
2045 <sect3 renderas="sect4" id="forward"><title>forward</title>
2048 <term>Specifies:</term>
2051 To which parent HTTP proxy specific requests should be routed.
2056 <term>Type of value:</term>
2059 <replaceable class="parameter">target_pattern</replaceable>
2060 <replaceable class="parameter">http_parent</replaceable>[:<replaceable class="parameter">port</replaceable>]
2063 where <replaceable class="parameter">target_pattern</replaceable> is a <link linkend="af-patterns">URL pattern</link>
2064 that specifies to which requests (i.e. URLs) this forward rule shall apply. Use <literal>/</literal> to
2065 denote <quote>all URLs</quote>.
2066 <replaceable class="parameter">http_parent</replaceable>[:<replaceable class="parameter">port</replaceable>]
2067 is the DNS name or IP address of the parent HTTP proxy through which the requests should be forwarded,
2068 optionally followed by its listening port (default: 8000).
2069 Use a single dot (<literal>.</literal>) to denote <quote>no forwarding</quote>.
2074 <term>Default value:</term>
2076 <para><emphasis>Unset</emphasis></para>
2080 <term>Effect if unset:</term>
2083 Don't use parent HTTP proxies.
2091 If <replaceable class="parameter">http_parent</replaceable> is <quote>.</quote>, then requests are not
2092 forwarded to another HTTP proxy but are made directly to the web servers.
2095 <replaceable class="parameter">http_parent</replaceable> can be a
2096 numerical IPv6 address (if
2097 <ulink url="http://tools.ietf.org/html/rfc3493">RFC 3493</ulink> is
2098 implemented). To prevent clashes with the port delimiter, the whole IP
2099 address has to be put into brackets. On the other hand a <replaceable
2100 class="parameter">target_pattern</replaceable> containing an IPv6 address
2101 has to be put into angle brackets (normal brackets are reserved for
2102 regular expressions already).
2105 Multiple lines are OK, they are checked in sequence, and the last match wins.
2110 <term>Examples:</term>
2113 Everything goes to an example parent proxy, except SSL on port 443 (which it doesn't handle):
2116 forward / parent-proxy.example.org:8080
2120 Everything goes to our example ISP's caching proxy, except for requests
2121 to that ISP's sites:
2124 forward / caching-proxy.isp.example.net:8000
2125 forward .isp.example.net .
2128 Parent proxy specified by an IPv6 address:
2131 forward / [2001:DB8::1]:8000
2134 Suppose your parent proxy doesn't support IPv6:
2137 forward / parent-proxy.example.org:8000
2138 forward ipv6-server.example.org .
2139 forward <[2-3][0-9a-f][0-9a-f][0-9a-f]:*> .
2147 <!-- ~~~~~ New section ~~~~~ -->
2148 <sect3 renderas="sect4" id="socks"><title>
2149 forward-socks4, forward-socks4a, forward-socks5 and forward-socks5t</title>
2150 <anchor id="forward-socks4">
2151 <anchor id="forward-socks4a">
2155 <term>Specifies:</term>
2158 Through which SOCKS proxy (and optionally to which parent HTTP proxy) specific requests should be routed.
2163 <term>Type of value:</term>
2166 <replaceable class="parameter">target_pattern</replaceable>
2167 <replaceable class="parameter">socks_proxy</replaceable>[:<replaceable class="parameter">port</replaceable>]
2168 <replaceable class="parameter">http_parent</replaceable>[:<replaceable class="parameter">port</replaceable>]
2171 where <replaceable class="parameter">target_pattern</replaceable> is a
2172 <link linkend="af-patterns">URL pattern</link> that specifies to which
2173 requests (i.e. URLs) this forward rule shall apply. Use <literal>/</literal> to
2174 denote <quote>all URLs</quote>. <replaceable class="parameter">http_parent</replaceable>
2175 and <replaceable class="parameter">socks_proxy</replaceable>
2176 are IP addresses in dotted decimal notation or valid DNS names
2177 (<replaceable class="parameter">http_parent</replaceable>
2178 may be <quote>.</quote> to denote <quote>no HTTP forwarding</quote>), and the optional
2179 <replaceable class="parameter">port</replaceable> parameters are TCP ports,
2180 i.e. integer values from 1 to 65535
2185 <term>Default value:</term>
2187 <para><emphasis>Unset</emphasis></para>
2191 <term>Effect if unset:</term>
2194 Don't use SOCKS proxies.
2202 Multiple lines are OK, they are checked in sequence, and the last match wins.
2205 The difference between <literal>forward-socks4</literal> and <literal>forward-socks4a</literal>
2206 is that in the SOCKS 4A protocol, the DNS resolution of the target hostname happens on the SOCKS
2207 server, while in SOCKS 4 it happens locally.
2210 With <literal>forward-socks5</literal> the DNS resolution will happen on the remote server as well.
2213 <literal>forward-socks5t</literal> works like vanilla <literal>forward-socks5</literal> but
2214 lets &my-app; additionally use Tor-specific SOCKS extensions. Currently the only supported
2215 SOCKS extension is optimistic data which can reduce the latency for the first request made
2216 on a newly created connection.
2219 <replaceable class="parameter">socks_proxy</replaceable> and
2220 <replaceable class="parameter">http_parent</replaceable> can be a
2221 numerical IPv6 address (if
2222 <ulink url="http://tools.ietf.org/html/rfc3493">RFC 3493</ulink> is
2223 implemented). To prevent clashes with the port delimiter, the whole IP
2224 address has to be put into brackets. On the other hand a <replaceable
2225 class="parameter">target_pattern</replaceable> containing an IPv6 address
2226 has to be put into angle brackets (normal brackets are reserved for
2227 regular expressions already).
2230 If <replaceable class="parameter">http_parent</replaceable> is <quote>.</quote>, then requests are not
2231 forwarded to another HTTP proxy but are made (HTTP-wise) directly to the web servers, albeit through
2237 <term>Examples:</term>
2240 From the company example.com, direct connections are made to all
2241 <quote>internal</quote> domains, but everything outbound goes through
2242 their ISP's proxy by way of example.com's corporate SOCKS 4A gateway to
2246 forward-socks4a / socks-gw.example.com:1080 www-cache.isp.example.net:8080
2247 forward .example.com .
2250 A rule that uses a SOCKS 4 gateway for all destinations but no HTTP parent looks like this:
2253 forward-socks4 / socks-gw.example.com:1080 .
2257 To chain Privoxy and Tor, both running on the same system, you would use
2261 forward-socks5t / 127.0.0.1:9050 .
2264 Note that if you got Tor through one of the bundles, you may
2265 have to change the port from 9050 to 9150 (or even another one).
2266 For details, please check the documentation on the
2267 <ulink url="https://torproject.org/">Tor website</ulink>.
2270 The public <application>Tor</application> network can't be used to
2271 reach your local network, if you need to access local servers you
2272 therefore might want to make some exceptions:
2275 forward 192.168.*.*/ .
2277 forward 127.*.*.*/ .
2280 Unencrypted connections to systems in these address ranges will
2281 be as (un)secure as the local network is, but the alternative is that you
2282 can't reach the local network through <application>Privoxy</application>
2283 at all. Of course this may actually be desired and there is no reason
2284 to make these exceptions if you aren't sure you need them.
2287 If you also want to be able to reach servers in your local network by
2288 using their names, you will need additional exceptions that look like
2292 forward localhost/ .
2300 <![%user-man;[ <!-- not included in config due to length -->
2301 <!-- ~~~~~ New section ~~~~~ -->
2302 <sect3 renderas="sect4" id="advanced-forwarding-examples"><title>Advanced Forwarding Examples</title>
2305 If you have links to multiple ISPs that provide various special content
2306 only to their subscribers, you can configure multiple <application>Privoxies</application>
2307 which have connections to the respective ISPs to act as forwarders to each other, so that
2308 <emphasis>your</emphasis> users can see the internal content of all ISPs.
2312 Assume that host-a has a PPP connection to isp-a.example.net. And host-b has a PPP connection to
2313 isp-b.example.org. Both run <application>Privoxy</application>. Their forwarding
2314 configuration can look like this:
2323 forward .isp-b.example.net host-b:8118
2332 forward .isp-a.example.org host-a:8118
2336 Now, your users can set their browser's proxy to use either
2337 host-a or host-b and be able to browse the internal content
2338 of both isp-a and isp-b.
2342 If you intend to chain <application>Privoxy</application> and
2343 <application>squid</application> locally, then chaining as
2344 <literal>browser -> squid -> privoxy</literal> is the recommended way.
2348 Assuming that <application>Privoxy</application> and <application>squid</application>
2349 run on the same box, your <application>squid</application> configuration could then look like this:
2353 # Define Privoxy as parent proxy (without ICP)
2354 cache_peer 127.0.0.1 parent 8118 7 no-query
2356 # Define ACL for protocol FTP
2359 # Do not forward FTP requests to Privoxy
2360 always_direct allow ftp
2362 # Forward all the rest to Privoxy
2363 never_direct allow all</screen>
2366 You would then need to change your browser's proxy settings to <application>squid</application>'s address and port.
2367 Squid normally uses port 3128. If unsure consult <literal>http_port</literal> in <filename>squid.conf</filename>.
2371 You could just as well decide to only forward requests you suspect
2372 of leading to Windows executables through a virus-scanning parent proxy,
2373 say, on <literal>antivir.example.com</literal>, port 8010:
2378 forward /.*\.(exe|com|dll|zip)$ antivir.example.com:8010</screen>
2383 <sect3 renderas="sect4" id="forwarded-connect-retries"><title>forwarded-connect-retries</title>
2386 <term>Specifies:</term>
2389 How often Privoxy retries if a forwarded connection request fails.
2394 <term>Type of value:</term>
2397 <replaceable class="parameter">Number of retries.</replaceable>
2402 <term>Default value:</term>
2404 <para><emphasis>0</emphasis></para>
2408 <term>Effect if unset:</term>
2411 Connections forwarded through other proxies are treated like direct connections and no retry attempts are made.
2419 <replaceable class="parameter">forwarded-connect-retries</replaceable> is mainly interesting
2420 for socks4a connections, where <application>Privoxy</application> can't detect why the connections failed.
2421 The connection might have failed because of a DNS timeout in which case a retry makes sense,
2422 but it might also have failed because the server doesn't exist or isn't reachable. In this
2423 case the retry will just delay the appearance of Privoxy's error message.
2426 Note that in the context of this option, <quote>forwarded connections</quote> includes all connections
2427 that Privoxy forwards through other proxies. This option is not limited to the HTTP CONNECT method.
2430 Only use this option, if you are getting lots of forwarding-related error messages
2431 that go away when you try again manually. Start with a small value and check Privoxy's
2432 logfile from time to time, to see how many retries are usually needed.
2437 <term>Examples:</term>
2440 forwarded-connect-retries 1
2445 <![%config-file;[<literallayout>@@forwarded-connect-retries 0</literallayout>]]>
2451 <title>Miscellaneous</title>
2453 <sect3 renderas="sect4" id="accept-intercepted-requests"><title>accept-intercepted-requests</title>
2456 <term>Specifies:</term>
2459 Whether intercepted requests should be treated as valid.
2464 <term>Type of value:</term>
2467 <replaceable>0 or 1</replaceable>
2472 <term>Default value:</term>
2474 <para><emphasis>0</emphasis></para>
2478 <term>Effect if unset:</term>
2481 Only proxy requests are accepted, intercepted requests are treated as invalid.
2489 If you don't trust your clients and want to force them
2490 to use <application>Privoxy</application>, enable this
2491 option and configure your packet filter to redirect outgoing
2492 HTTP connections into <application>Privoxy</application>.
2495 Note that intercepting encrypted connections (HTTPS) isn't supported.
2498 Make sure that <application>Privoxy's</application> own requests
2499 aren't redirected as well. Additionally take care that
2500 <application>Privoxy</application> can't intentionally connect
2501 to itself, otherwise you could run into redirection loops if
2502 <application>Privoxy's</application> listening port is reachable
2503 by the outside or an attacker has access to the pages you visit.
2506 If you are running Privoxy as intercepting proxy without being
2507 able to intercept all client requests you may want to adjust
2508 the CGI templates to make sure they don't reference content from
2514 <term>Examples:</term>
2517 accept-intercepted-requests 1
2522 <![%config-file;[<literallayout>@@accept-intercepted-requests 0</literallayout>]]>
2525 <sect3 renderas="sect4" id="allow-cgi-request-crunching"><title>allow-cgi-request-crunching</title>
2528 <term>Specifies:</term>
2531 Whether requests to <application>Privoxy's</application> CGI pages can be blocked or redirected.
2536 <term>Type of value:</term>
2539 <replaceable>0 or 1</replaceable>
2544 <term>Default value:</term>
2546 <para><emphasis>0</emphasis></para>
2550 <term>Effect if unset:</term>
2553 <application>Privoxy</application> ignores block and redirect actions for its CGI pages.
2561 By default <application>Privoxy</application> ignores block or redirect actions
2562 for its CGI pages. Intercepting these requests can be useful in multi-user
2563 setups to implement fine-grained access control, but it can also render the complete
2564 web interface useless and make debugging problems painful if done without care.
2567 Don't enable this option unless you're sure that you really need it.
2572 <term>Examples:</term>
2575 allow-cgi-request-crunching 1
2580 <![%config-file;[<literallayout>@@allow-cgi-request-crunching 0</literallayout>]]>
2583 <sect3 renderas="sect4" id="split-large-forms"><title>split-large-forms</title>
2586 <term>Specifies:</term>
2589 Whether the CGI interface should stay compatible with broken HTTP clients.
2594 <term>Type of value:</term>
2597 <replaceable>0 or 1</replaceable>
2602 <term>Default value:</term>
2604 <para><emphasis>0</emphasis></para>
2608 <term>Effect if unset:</term>
2611 The CGI form generate long GET URLs.
2619 <application>Privoxy's</application> CGI forms can lead to
2620 rather long URLs. This isn't a problem as far as the HTTP
2621 standard is concerned, but it can confuse clients with arbitrary
2622 URL length limitations.
2625 Enabling split-large-forms causes <application>Privoxy</application>
2626 to divide big forms into smaller ones to keep the URL length down.
2627 It makes editing a lot less convenient and you can no longer
2628 submit all changes at once, but at least it works around this
2632 If you don't notice any editing problems, there is no reason
2633 to enable this option, but if one of the submit buttons appears
2634 to be broken, you should give it a try.
2639 <term>Examples:</term>
2647 <![%config-file;[<literallayout>@@split-large-forms 0</literallayout>]]>
2650 <sect3 renderas="sect4" id="keep-alive-timeout"><title>keep-alive-timeout</title>
2653 <term>Specifies:</term>
2656 Number of seconds after which an open connection will no longer be reused.
2661 <term>Type of value:</term>
2664 <replaceable>Time in seconds.</replaceable>
2669 <term>Default value:</term>
2675 <term>Effect if unset:</term>
2678 Connections are not kept alive.
2686 This option allows clients to keep the connection to &my-app;
2687 alive. If the server supports it, &my-app; will keep
2688 the connection to the server alive as well. Under certain
2689 circumstances this may result in speed-ups.
2692 By default, &my-app; will close the connection to the server if
2693 the client connection gets closed, or if the specified timeout
2694 has been reached without a new request coming in. This behaviour
2695 can be changed with the <ulink
2696 url="#CONNECTION-SHARING">connection-sharing</ulink> option.
2699 This option has no effect if <application>Privoxy</application>
2700 has been compiled without keep-alive support.
2703 Note that a timeout of five seconds as used in the default
2704 configuration file significantly decreases the number of
2705 connections that will be reused. The value is used because
2706 some browsers limit the number of connections they open to
2707 a single host and apply the same limit to proxies. This can
2708 result in a single website <quote>grabbing</quote> all the
2709 connections the browser allows, which means connections to
2710 other websites can't be opened until the connections currently
2714 Several users have reported this as a Privoxy bug, so the
2715 default value has been reduced. Consider increasing it to
2716 300 seconds or even more if you think your browser can handle
2717 it. If your browser appears to be hanging, it probably can't.
2722 <term>Examples:</term>
2725 keep-alive-timeout 300
2730 <![%config-file;[<literallayout>@@keep-alive-timeout 5</literallayout>]]>
2734 <sect3 renderas="sect4" id="tolerate-pipelining"><title>tolerate-pipelining</title>
2737 <term>Specifies:</term>
2740 Whether or not pipelined requests should be served.
2745 <term>Type of value:</term>
2748 <replaceable>0 or 1.</replaceable>
2753 <term>Default value:</term>
2759 <term>Effect if unset:</term>
2762 If Privoxy receives more than one request at once, it terminates the
2763 client connection after serving the first one.
2771 &my-app; currently doesn't pipeline outgoing requests,
2772 thus allowing pipelining on the client connection is not
2773 guaranteed to improve the performance.
2776 By default &my-app; tries to discourage clients from pipelining
2777 by discarding aggressively pipelined requests, which forces the
2778 client to resend them through a new connection.
2781 This option lets &my-app; tolerate pipelining. Whether or not
2782 that improves performance mainly depends on the client configuration.
2785 If you are seeing problems with pages not properly loading,
2786 disabling this option could work around the problem.
2791 <term>Examples:</term>
2794 tolerate-pipelining 1
2799 <![%config-file;[<literallayout>@@tolerate-pipelining 1</literallayout>]]>
2803 <sect3 renderas="sect4" id="default-server-timeout"><title>default-server-timeout</title>
2806 <term>Specifies:</term>
2809 Assumed server-side keep-alive timeout if not specified by the server.
2814 <term>Type of value:</term>
2817 <replaceable>Time in seconds.</replaceable>
2822 <term>Default value:</term>
2828 <term>Effect if unset:</term>
2831 Connections for which the server didn't specify the keep-alive
2832 timeout are not reused.
2840 Enabling this option significantly increases the number of connections
2841 that are reused, provided the <ulink
2842 url="#KEEP-ALIVE-TIMEOUT">keep-alive-timeout</ulink> option
2846 While it also increases the number of connections problems
2847 when &my-app; tries to reuse a connection that already has
2848 been closed on the server side, or is closed while &my-app;
2849 is trying to reuse it, this should only be a problem if it
2850 happens for the first request sent by the client. If it happens
2851 for requests on reused client connections, &my-app; will simply
2852 close the connection and the client is supposed to retry the
2853 request without bothering the user.
2856 Enabling this option is therefore only recommended if the
2858 url="#CONNECTION-SHARING">connection-sharing</ulink> option
2862 It is an error to specify a value larger than the <ulink
2863 url="#KEEP-ALIVE-TIMEOUT">keep-alive-timeout</ulink> value.
2866 This option has no effect if <application>Privoxy</application>
2867 has been compiled without keep-alive support.
2872 <term>Examples:</term>
2875 default-server-timeout 60
2880 <![%config-file;[<literallayout>@@#default-server-timeout 60</literallayout>]]>
2884 <sect3 renderas="sect4" id="connection-sharing"><title>connection-sharing</title>
2887 <term>Specifies:</term>
2890 Whether or not outgoing connections that have been kept alive
2891 should be shared between different incoming connections.
2896 <term>Type of value:</term>
2899 <replaceable>0 or 1</replaceable>
2904 <term>Default value:</term>
2910 <term>Effect if unset:</term>
2913 Connections are not shared.
2921 This option has no effect if <application>Privoxy</application>
2922 has been compiled without keep-alive support, or if it's disabled.
2930 Note that reusing connections doesn't necessary cause speedups.
2931 There are also a few privacy implications you should be aware of.
2934 If this option is effective, outgoing connections are shared between
2935 clients (if there are more than one) and closing the browser that initiated
2936 the outgoing connection does no longer affect the connection between &my-app;
2937 and the server unless the client's request hasn't been completed yet.
2940 If the outgoing connection is idle, it will not be closed until either
2941 <application>Privoxy's</application> or the server's timeout is reached.
2942 While it's open, the server knows that the system running &my-app; is still
2946 If there are more than one client (maybe even belonging to multiple users),
2947 they will be able to reuse each others connections. This is potentially
2948 dangerous in case of authentication schemes like NTLM where only the
2949 connection is authenticated, instead of requiring authentication for
2953 If there is only a single client, and if said client can keep connections
2954 alive on its own, enabling this option has next to no effect. If the client
2955 doesn't support connection keep-alive, enabling this option may make sense
2956 as it allows &my-app; to keep outgoing connections alive even if the client
2957 itself doesn't support it.
2960 You should also be aware that enabling this option increases the likelihood
2961 of getting the "No server or forwarder data" error message, especially if you
2962 are using a slow connection to the Internet.
2965 This option should only be used by experienced users who
2966 understand the risks and can weight them against the benefits.
2971 <term>Examples:</term>
2974 connection-sharing 1
2979 <![%config-file;[<literallayout>@@#connection-sharing 1</literallayout>]]>
2983 <sect3 renderas="sect4" id="socket-timeout"><title>socket-timeout</title>
2986 <term>Specifies:</term>
2989 Number of seconds after which a socket times out if
2990 no data is received.
2995 <term>Type of value:</term>
2998 <replaceable>Time in seconds.</replaceable>
3003 <term>Default value:</term>
3009 <term>Effect if unset:</term>
3012 A default value of 300 seconds is used.
3020 The default is quite high and you probably want to reduce it.
3021 If you aren't using an occasionally slow proxy like Tor, reducing
3022 it to a few seconds should be fine.
3027 <term>Examples:</term>
3035 <![%config-file;[<literallayout>@@socket-timeout 300</literallayout>]]>
3039 <sect3 renderas="sect4" id="max-client-connections"><title>max-client-connections</title>
3042 <term>Specifies:</term>
3045 Maximum number of client connections that will be served.
3050 <term>Type of value:</term>
3053 <replaceable>Positive number.</replaceable>
3058 <term>Default value:</term>
3064 <term>Effect if unset:</term>
3067 Connections are served until a resource limit is reached.
3075 &my-app; creates one thread (or process) for every incoming client
3076 connection that isn't rejected based on the access control settings.
3079 If the system is powerful enough, &my-app; can theoretically deal with
3080 several hundred (or thousand) connections at the same time, but some
3081 operating systems enforce resource limits by shutting down offending
3082 processes and their default limits may be below the ones &my-app; would
3083 require under heavy load.
3086 Configuring &my-app; to enforce a connection limit below the thread
3087 or process limit used by the operating system makes sure this doesn't
3088 happen. Simply increasing the operating system's limit would work too,
3089 but if &my-app; isn't the only application running on the system,
3090 you may actually want to limit the resources used by &my-app;.
3093 If &my-app; is only used by a single trusted user, limiting the
3094 number of client connections is probably unnecessary. If there
3095 are multiple possibly untrusted users you probably still want to
3096 additionally use a packet filter to limit the maximal number of
3097 incoming connections per client. Otherwise a malicious user could
3098 intentionally create a high number of connections to prevent other
3099 users from using &my-app;.
3102 Obviously using this option only makes sense if you choose a limit
3103 below the one enforced by the operating system.
3106 One most POSIX-compliant systems &my-app; can't properly deal with
3107 more than FD_SETSIZE file descriptors at the same time and has to reject
3108 connections if the limit is reached. This will likely change in a
3109 future version, but currently this limit can't be increased without
3110 recompiling &my-app; with a different FD_SETSIZE limit.
3115 <term>Examples:</term>
3118 max-client-connections 256
3123 <![%config-file;[<literallayout>@@#max-client-connections 256</literallayout>]]>
3127 <sect3 renderas="sect4" id="listen-backlog"><title>listen-backlog</title>
3130 <term>Specifies:</term>
3133 Connection queue length requested from the operating system.
3138 <term>Type of value:</term>
3141 <replaceable>Number.</replaceable>
3146 <term>Default value:</term>
3152 <term>Effect if unset:</term>
3155 A connection queue length of 128 is requested from the operating system.
3163 Under high load incoming connection may queue up before Privoxy
3164 gets around to serve them. The queue length is limitted by the
3165 operating system. Once the queue is full, additional connections
3166 are dropped before Privoxy can accept and serve them.
3169 Increasing the queue length allows Privoxy to accept more
3170 incomming connections that arrive roughly at the same time.
3173 Note that Privoxy can only request a certain queue length,
3174 whether or not the requested length is actually used depends
3175 on the operating system which may use a different length instead.
3178 On many operating systems a limit of -1 can be specified to
3179 instruct the operating system to use the maximum queue length
3180 allowed. Check the listen man page to see if your platform allows this.
3183 On some platforms you can use "netstat -Lan -p tcp" to see the effective
3187 Effectively using a value above 128 usually requires changing
3188 the system configuration as well. On FreeBSD-based system the
3189 limit is controlled by the kern.ipc.soacceptqueue sysctl.
3194 <term>Examples:</term>
3202 <![%config-file;[<literallayout>@@#listen-backlog -1</literallayout>]]>
3206 <sect3 renderas="sect4" id="enable-accept-filter"><title>enable-accept-filter</title>
3209 <term>Specifies:</term>
3212 Whether or not Privoxy should use an accept filter
3217 <term>Type of value:</term>
3220 <replaceable>0 or 1</replaceable>
3225 <term>Default value:</term>
3231 <term>Effect if unset:</term>
3234 No accept filter is enabled.
3242 Accept filters reduce the number of context switches by not
3243 passing sockets for new connections to Privoxy until a complete
3244 HTTP request is available.
3247 As a result, Privoxy can process the whole request right away
3248 without having to wait for additional data first.
3251 For this option to work, Privoxy has to be compiled with
3252 FEATURE_ACCEPT_FILTER and the operating system has to support
3253 it (which may require loading a kernel module).
3256 Currently accept filters are only supported on FreeBSD-based
3258 <ulink url="https://www.freebsd.org/cgi/man.cgi?query=accf_http">accf_http(9)
3260 to learn how to enable the support in the operating system.
3265 <term>Examples:</term>
3268 enable-accept-filter 1
3273 <![%config-file;[<literallayout>@@#enable-accept-filter 1</literallayout>]]>
3277 <sect3 renderas="sect4" id="handle-as-empty-doc-returns-ok"><title>handle-as-empty-doc-returns-ok</title>
3280 <term>Specifies:</term>
3283 The status code Privoxy returns for pages blocked with
3284 <!-- URL will only end up in the user manual so the relative link should work. -->
3285 <literal><ulink url="actions-file.html#HANDLE-AS-EMPTY-DOCUMENT">+handle-as-empty-document</ulink></literal>.
3290 <term>Type of value:</term>
3293 <replaceable>0 or 1</replaceable>
3298 <term>Default value:</term>
3304 <term>Effect if unset:</term>
3307 Privoxy returns a status 403(forbidden) for all blocked pages.
3312 <term>Effect if set:</term>
3315 Privoxy returns a status 200(OK) for pages blocked with +handle-as-empty-document
3316 and a status 403(Forbidden) for all other blocked pages.
3324 This directive was added as a work-around for Firefox bug 492459:
3325 <quote>Websites are no longer rendered if SSL requests for JavaScripts are blocked by a proxy.</quote>
3326 (<ulink url="https://bugzilla.mozilla.org/show_bug.cgi?id=492459"
3327 >https://bugzilla.mozilla.org/show_bug.cgi?id=492459</ulink>),
3328 the bug has been fixed for quite some time, but this directive is also useful
3329 to make it harder for websites to detect whether or not resources are being
3335 <![%config-file;[<literallayout>@@#handle-as-empty-doc-returns-ok 1</literallayout>]]>
3339 <sect3 renderas="sect4" id="enable-compression"><title>enable-compression</title>
3342 <term>Specifies:</term>
3345 Whether or not buffered content is compressed before delivery.
3350 <term>Type of value:</term>
3353 <replaceable>0 or 1</replaceable>
3358 <term>Default value:</term>
3364 <term>Effect if unset:</term>
3367 Privoxy does not compress buffered content.
3372 <term>Effect if set:</term>
3375 Privoxy compresses buffered content before delivering it to the client,
3376 provided the client supports it.
3384 This directive is only supported if Privoxy has been compiled with
3385 FEATURE_COMPRESSION, which should not to be confused with FEATURE_ZLIB.
3388 Compressing buffered content is mainly useful if Privoxy and the
3389 client are running on different systems. If they are running on the
3390 same system, enabling compression is likely to slow things down.
3391 If you didn't measure otherwise, you should assume that it does
3392 and keep this option disabled.
3395 Privoxy will not compress buffered content below a certain length.
3400 <![%config-file;[<literallayout>@@#enable-compression 1</literallayout>]]>
3404 <sect3 renderas="sect4" id="compression-level"><title>compression-level</title>
3407 <term>Specifies:</term>
3410 The compression level that is passed to the zlib library when compressing buffered content.
3415 <term>Type of value:</term>
3418 <replaceable>Positive number ranging from 0 to 9.</replaceable>
3423 <term>Default value:</term>
3432 Compressing the data more takes usually longer than compressing
3433 it less or not compressing it at all. Which level is best depends
3434 on the connection between Privoxy and the client. If you can't
3435 be bothered to benchmark it for yourself, you should stick with
3436 the default and keep compression disabled.
3439 If compression is disabled, the compression level is irrelevant.
3444 <term>Examples:</term>
3447 # Best speed (compared to the other levels)
3451 # No compression. Only useful for testing as the added header
3452 # slightly increases the amount of data that has to be sent.
3453 # If your benchmark shows that using this compression level
3454 # is superior to using no compression at all, the benchmark
3455 # is likely to be flawed.
3461 <![%config-file;[<literallayout>@@#compression-level 1</literallayout>]]>
3465 <sect3 renderas="sect4" id="client-header-order"><title>client-header-order</title>
3468 <term>Specifies:</term>
3471 The order in which client headers are sorted before forwarding them.
3476 <term>Type of value:</term>
3479 <replaceable>Client header names delimited by spaces or tabs</replaceable>
3484 <term>Default value:</term>
3493 By default &my-app; leaves the client headers in the order they
3494 were sent by the client. Headers are modified in-place, new headers
3495 are added at the end of the already existing headers.
3498 The header order can be used to fingerprint client requests
3499 independently of other headers like the User-Agent.
3502 This directive allows to sort the headers differently to better
3503 mimic a different User-Agent. Client headers will be emitted
3504 in the order given, headers whose name isn't explicitly specified
3505 are added at the end.
3508 Note that sorting headers in an uncommon way will make fingerprinting
3509 actually easier. Encrypted headers are not affected by this directive.
3514 <![%config-file;[<literallayout>@@#client-header-order Host \
3531 <sect3 renderas="sect4" id="client-specific-tag"><title>client-specific-tag</title>
3534 <term>Specifies:</term>
3537 The name of a tag that will always be set for clients that
3538 requested it through the webinterface.
3543 <term>Type of value:</term>
3546 <replaceable>Tag name followed by a description that will be shown in the webinterface</replaceable>
3551 <term>Default value:</term>
3561 This is an experimental feature. The syntax is likely to change
3566 Client-specific tags allow Privoxy admins to create different
3567 profiles and let the users chose which one they want without
3568 impacting other users.
3571 One use case is allowing users to circumvent certain blocks
3572 without having to allow them to circumvent all blocks.
3573 This is not possible with the
3574 <link linkend="enable-remote-toggle">enable-remote-toggle feature</link>
3575 because it would bluntly disable all blocks for all users and also affect
3576 other actions like filters.
3577 It also is set globally which renders it useless in most multi-user setups.
3580 After a client-specific tag has been defined with the client-specific-tag
3581 directive, action sections can be activated based on the tag by using a
3582 <ulink url="actions-file.html#CLIENT-TAG-PATTERN">CLIENT-TAG</ulink> pattern.
3583 The CLIENT-TAG pattern is evaluated at the same priority
3584 as URL patterns, as a result the last matching pattern wins.
3585 Tags that are created based on client or server headers are evaluated
3586 later on and can overrule CLIENT-TAG and URL patterns!
3589 The tag is set for all requests that come from clients that requested
3591 Note that "clients" are differentiated by IP address,
3592 if the IP address changes the tag has to be requested again.
3595 Clients can request tags to be set by using the CGI interface <ulink
3596 url="http://config.privoxy.org/client-tags">http://config.privoxy.org/client-tags</ulink>.
3597 The specific tag description is only used on the web page and should
3598 be phrased in away that the user understand the effect of the tag.
3603 <term>Examples:</term>
3606 # Define a couple of tags, the described effect requires action sections
3607 # that are enabled based on CLIENT-TAG patterns.
3608 client-specific-tag circumvent-blocks Overrule blocks but do not affect other actions
3609 disable-content-filters Disable content-filters but do not affect other actions
3616 <!-- ~ End section ~ -->
3618 <sect3 renderas="sect4" id="client-tag-lifetime"><title>client-tag-lifetime</title>
3621 <term>Specifies:</term>
3624 How long a temporarily enabled tag remains enabled.
3629 <term>Type of value:</term>
3632 <replaceable>Time in seconds.</replaceable>
3637 <term>Default value:</term>
3647 This is an experimental feature. The syntax is likely to change
3652 In case of some tags users may not want to enable them permanently,
3653 but only for a short amount of time, for example to circumvent a block
3654 that is the result of an overly-broad URL pattern.
3657 The CGI interface <ulink
3658 url="http://config.privoxy.org/client-tags">http://config.privoxy.org/client-tags</ulink>
3659 therefore provides a "enable this tag temporarily" option.
3660 If it is used, the tag will be set until the client-tag-lifetime
3666 <term>Examples:</term>
3669 # Increase the time to life for temporarily enabled tags to 3 minutes
3670 client-tag-lifetime 180
3677 <!-- ~ End section ~ -->
3679 <sect3 renderas="sect4" id="trust-x-forwarded-for"><title>trust-x-forwarded-for</title>
3682 <term>Specifies:</term>
3685 Whether or not Privoxy should use IP addresses specified with the X-Forwarded-For header
3690 <term>Type of value:</term>
3693 <replaceable>0 or one</replaceable>
3698 <term>Default value:</term>
3708 This is an experimental feature. The syntax is likely to change
3713 If clients reach Privoxy through another proxy, for example a load
3714 balancer, Privoxy can't tell the client's IP address from the connection.
3715 If multiple clients use the same proxy, they will share the same
3716 client tag settings which is usually not desired.
3719 This option lets Privoxy use the X-Forwarded-For header value as
3720 client IP address. If the proxy sets the header, multiple clients
3721 using the same proxy do not share the same client tag settings.
3724 This option should only be enabled if Privoxy can only be reached
3725 through a proxy and if the proxy can be trusted to set the header
3726 correctly. It is recommended that ACL are used to make sure only
3727 trusted systems can reach Privoxy.
3730 If access to Privoxy isn't limited to trusted systems, this option
3731 would allow malicious clients to change the client tags for other
3732 clients or increase Privoxy's memory requirements by registering
3733 lots of client tag settings for clients that don't exist.
3738 <term>Examples:</term>
3741 # Allow systems that can reach Privoxy to provide the client
3742 # IP address with a X-Forwarded-For header.
3743 trust-x-forwarded-for 1
3750 <!-- ~ End section ~ -->
3752 <!-- ~~~~~ New section ~~~~~ -->
3754 <sect3 renderas="sect4" id="receive-buffer-size"><title>receive-buffer-size</title>
3757 <term>Specifies:</term>
3760 The size of the buffer Privoxy uses to receive data from the server.
3765 <term>Type of value:</term>
3768 <replaceable>Size in bytes</replaceable>
3773 <term>Default value:</term>
3782 Increasing the receive-buffer-size increases Privoxy's memory usage but
3783 can lower the number of context switches and thereby reduce the
3784 cpu usage and potentially increase the throughput.
3787 This is mostly relevant for fast network connections and
3788 large downloads that don't require filtering.
3791 Reducing the buffer size reduces the amount of memory Privoxy
3792 needs to handle the request but increases the number of systemcalls
3793 and may reduce the throughput.
3796 A dtrace command like:
3797 <quote>sudo dtrace -n 'syscall::read:return /execname == "privoxy"/ { @[execname] = llquantize(arg0, 10, 0, 5, 20); @m = max(arg0)}'</quote>
3798 can be used to properly tune the receive-buffer-size.
3799 On systems without dtrace, strace or truss may be used as
3800 less convenient alternatives.
3803 If the buffer is too large it will increase Privoxy's memory
3804 footprint without any benefit. As the memory is (currently)
3805 cleared before using it, a buffer that is too large can
3806 actually reduce the throughput.
3811 <term>Examples:</term>
3814 # Increase the receive buffer size
3815 receive-buffer-size 32768
3822 <!-- ~ End section ~ -->
3826 <!-- ~~~~~ New section ~~~~~ -->
3828 <sect2 id="windows-gui">
3829 <title>Windows GUI Options</title>
3831 <application>Privoxy</application> has a number of options specific to the
3832 Windows GUI interface:
3835 <anchor id="activity-animation">
3836 <![%config-file;[<para>@@</para>]]> <!-- for spacing -->
3838 If <quote>activity-animation</quote> is set to 1, the
3839 <application>Privoxy</application> icon will animate when
3840 <quote>Privoxy</quote> is active. To turn off, set to 0.
3843 <![%config-file;[<literallayout>@@#activity-animation 1</literallayout>]]>
3849 <emphasis>activity-animation 1</emphasis>
3856 <anchor id="log-messages">
3857 <![%config-file;[<para>@@</para>]]> <!-- for spacing -->
3859 If <quote>log-messages</quote> is set to 1,
3860 <application>Privoxy</application> copies log messages to the console
3862 The log detail depends on the <link linkend="debug">debug</link> directive.
3865 <![%config-file;[<literallayout>@@#log-messages 1</literallayout>]]>
3871 <emphasis>log-messages 1</emphasis>
3878 <anchor id="log-buffer-size">
3879 <![%config-file;[<para>@@</para>]]> <!-- for spacing -->
3881 If <quote>log-buffer-size</quote> is set to 1, the size of the log buffer,
3882 i.e. the amount of memory used for the log messages displayed in the
3883 console window, will be limited to <quote>log-max-lines</quote> (see below).
3887 Warning: Setting this to 0 will result in the buffer to grow infinitely and
3888 eat up all your memory!
3891 <![%config-file;[<literallayout>@@#log-buffer-size 1</literallayout>]]>
3897 <emphasis>log-buffer-size 1</emphasis>
3904 <anchor id="log-max-lines">
3905 <![%config-file;[<para>@@</para>]]> <!-- for spacing -->
3907 <application>log-max-lines</application> is the maximum number of lines held
3908 in the log buffer. See above.
3911 <![%config-file;[<literallayout>@@#log-max-lines 200</literallayout>]]>
3917 <emphasis>log-max-lines 200</emphasis>
3924 <anchor id="log-highlight-messages">
3925 <![%config-file;[<para>@@</para>]]> <!-- for spacing -->
3927 If <quote>log-highlight-messages</quote> is set to 1,
3928 <application>Privoxy</application> will highlight portions of the log
3929 messages with a bold-faced font:
3932 <![%config-file;[<literallayout>@@#log-highlight-messages 1</literallayout>]]>
3938 <emphasis>log-highlight-messages 1</emphasis>
3945 <anchor id="log-font-name">
3946 <![%config-file;[<para>@@</para>]]> <!-- for spacing -->
3948 The font used in the console window:
3951 <![%config-file;[<literallayout>@@#log-font-name Comic Sans MS</literallayout>]]>
3957 <emphasis>log-font-name Comic Sans MS</emphasis>
3964 <anchor id="log-font-size">
3965 <![%config-file;[<para>@@</para>]]> <!-- for spacing -->
3967 Font size used in the console window:
3970 <![%config-file;[<literallayout>@@#log-font-size 8</literallayout>]]>
3976 <emphasis>log-font-size 8</emphasis>
3983 <anchor id="show-on-task-bar">
3984 <![%config-file;[<para>@@</para>]]> <!-- for spacing -->
3986 <quote>show-on-task-bar</quote> controls whether or not
3987 <application>Privoxy</application> will appear as a button on the Task bar
3991 <![%config-file;[<literallayout>@@#show-on-task-bar 0</literallayout>]]>
3997 <emphasis>show-on-task-bar 0</emphasis>
4004 <anchor id="close-button-minimizes">
4005 <![%config-file;[<para>@@</para>]]> <!-- for spacing -->
4007 If <quote>close-button-minimizes</quote> is set to 1, the Windows close
4008 button will minimize <application>Privoxy</application> instead of closing
4009 the program (close with the exit option on the File menu).
4012 <![%config-file;[<literallayout>@@#close-button-minimizes 1</literallayout>]]>
4018 <emphasis>close-button-minimizes 1</emphasis>
4025 <anchor id="hide-console">
4026 <![%config-file;[<para>@@</para>]]> <!-- for spacing -->
4028 The <quote>hide-console</quote> option is specific to the MS-Win console
4029 version of <application>Privoxy</application>. If this option is used,
4030 <application>Privoxy</application> will disconnect from and hide the
4034 <![%config-file;[<literallayout>@@#hide-console</literallayout>]]>
4040 #<emphasis>hide-console</emphasis>
4050 <!-- end config content common to both outputs -->
4053 <!-- These are dummy anchors to keep the processor quiet -->
4054 <!-- when building config-file only (ie. they are used in u-m only) -->
4057 <anchor id="filter">
4058 <anchor id="filter-file">
4060 <anchor id="actions-file">
4061 <anchor id="af-patterns">
4065 <!-- eof p-config.sgml -->