2 File : doc/source/p-config.sgml
4 Purpose : Used with other docs and files only.
6 Copyright (C) 2001-2018 Privoxy Developers https://www.privoxy.org/
9 ========================================================================
10 NOTE: Please read developer-manual/documentation.html before touching
11 anything in this, or other Privoxy documentation.
12 ========================================================================
15 This file contains all the config file comments and options. It used to
16 build both the user-manual config sections, and all of config (yes, the main
19 Rationale: This is broken up into two files since a file with a prolog
20 (DTD, etc) cannot be sourced as a secondary file. config.sgml is basically
21 a wrapper for this file.
25 OPTIONS: The actual options are included in this file and prefixed with
26 '@@', and processed by the Makefile to strip the '@@'. Default options
27 that should appear commented out should be listed as: '@@#OPTION'.
28 Otherwise, as '@@OPTION'. Example:
30 @@listen-address 127.0.0.1:8118
32 The Makefile does significant other processing too. The final results
33 should be checked to make sure that the perl processing does not
34 fubar something!!! Makefile processing requires w3m, fmt (shell line
38 This file is included into:
41 config (the actual Privoxy config file)
46 <!-- This part only goes into user-manual -->
48 <title>The Main Configuration File</title>
51 By default, the main configuration file is named <filename>config</filename>,
52 with the exception of Windows, where it is named <filename>config.txt</filename>.
53 Configuration lines consist of an initial keyword followed by a list of
54 values, all separated by whitespace (any number of spaces or tabs). For
62 <emphasis>confdir /etc/privoxy</emphasis></literallayout>
68 Assigns the value <literal>/etc/privoxy</literal> to the option
69 <literal>confdir</literal> and thus indicates that the configuration
70 directory is named <quote>/etc/privoxy/</quote>.
74 All options in the config file except for <literal>confdir</literal> and
75 <literal>logdir</literal> are optional. Watch out in the below description
76 for what happens if you leave them unset.
80 The main config file controls all aspects of <application>Privoxy</application>'s
81 operation that are not location dependent (i.e. they apply universally, no matter
82 where you may be surfing). Like the filter and action files, the config file is
83 a plain text file and can be modified with a text editor like emacs, vim or
91 <!-- This part only goes into the config file -->
94 @@TITLE<!-- between the @@ is stripped by Makefile -->@@
95 Sample Configuration File for Privoxy &p-version;
98 Copyright (C) 2001-2018 Privoxy Developers https://www.privoxy.org/
103 ##################################################################
108 II. FORMAT OF THE CONFIGURATION FILE #
110 1. LOCAL SET-UP DOCUMENTATION #
111 2. CONFIGURATION AND LOG FILE LOCATIONS #
113 4. ACCESS CONTROL AND SECURITY #
116 7. WINDOWS GUI OPTIONS #
118 ##################################################################
122 <literallayout>I. INTRODUCTION
123 =============== <!-- fuck this madness --></literallayout>
126 This file holds Privoxy's main configuration. Privoxy detects
127 configuration changes automatically, so you don't have to restart it
128 unless you want to load a different configuration file.
131 The configuration will be reloaded with the first request after the
132 change was done, this request itself will still use the old configuration,
133 though. In other words: it takes two requests before you see the result of
134 your changes. Requests that are dropped due to ACL don't trigger reloads.
137 When starting Privoxy on Unix systems, give the location of this
138 file as last argument. On Windows systems, Privoxy will look for
139 this file with the name 'config.txt' in the current working directory
140 of the Privoxy process.
144 <literallayout><!-- funky spacing -->
146 II. FORMAT OF THE CONFIGURATION FILE
147 ====================================</literallayout>
150 Configuration lines consist of an initial keyword followed by a list
151 of values, all separated by whitespace (any number of spaces or
155 actionsfile default.action
158 Indicates that the actionsfile is named 'default.action'.
161 The '#' indicates a comment. Any part of a line following a '#' is
162 ignored, except if the '#' is preceded by a '\'.
165 Thus, by placing a # at the start of an existing configuration line,
166 you can make it a comment and it will be treated as if it weren't there.
167 This is called "commenting out" an option and can be useful. Removing
168 the # again is called "uncommenting".
171 Note that commenting out an option and leaving it at its default
172 are two completely different things! Most options behave very
173 differently when unset. See the "Effect if unset" explanation
174 in each option's description for details.
177 Long lines can be continued on the next line by using a `\' as
183 <!-- ************************************************ -->
184 <!-- The following is common to both outputs (mostly) -->
185 <!-- ************************************************ -->
189 <!-- ~~~~~ New section ~~~~~ -->
190 <sect2 id="local-set-up">
191 <title>Local Set-up Documentation</title>
194 If you intend to operate <application>Privoxy</application> for more users
195 than just yourself, it might be a good idea to let them know how to reach
196 you, what you block and why you do that, your policies, etc.
200 <!-- ~~~~~ New section ~~~~~ -->
201 <sect3 renderas="sect4" id="user-manual"><title>user-manual</title>
204 <term>Specifies:</term>
207 Location of the <application>Privoxy</application> User Manual.
212 <term>Type of value:</term>
214 <para>A fully qualified URI</para>
218 <term>Default value:</term>
220 <para><emphasis>Unset</emphasis></para>
224 <term>Effect if unset:</term>
227 <ulink url="https://www.privoxy.org/user-manual/">https://www.privoxy.org/<replaceable class="parameter">version</replaceable>/user-manual/</ulink>
228 will be used, where <replaceable class="parameter">version</replaceable> is the <application>Privoxy</application> version.
236 The User Manual URI is the single best source of information on
237 <application>Privoxy</application>, and is used for help links from some
238 of the internal CGI pages. The manual itself is normally packaged with the
239 binary distributions, so you probably want to set this to a locally
247 Unix, in local filesystem (may not work with all browsers):
249 <screen> user-manual file:///usr/share/doc/privoxy-&p-version;/user-manual/</screen>
251 Windows, in local filesystem, <emphasis>must</emphasis> use forward slash notation:
253 <screen> user-manual file:/c:/some-dir/privoxy-&p-version;/user-manual/</screen>
255 Windows, UNC notation (with forward slashes):
257 <screen> user-manual file://///some-server/some-path/privoxy-&p-version;/user-manual/</screen>
260 The best all purpose solution is simply to put the full local
261 <literal>PATH</literal> to where the <citetitle>User Manual</citetitle> is
264 <screen> user-manual /usr/share/doc/privoxy/user-manual</screen>
266 The User Manual is then available to anyone with access to
267 <application>Privoxy</application>, by following the built-in URL:
268 <literal>http://config.privoxy.org/user-manual/</literal>
269 (or the shortcut: <literal>http://p.p/user-manual/</literal>).
272 If the documentation is not on the local system, it can be accessed
273 from a remote server, as:
275 <screen> user-manual http://example.com/privoxy/user-manual/</screen>
277 <!-- this gets hammered in conversion to config. Text repeated below. -->
280 If set, this option should be <emphasis>the first option in the config
281 file</emphasis>, because it is used while the config file is being read
294 If set, this option should be the first option in the config
295 file, because it is used while the config file is being read.
304 <![%config-file;[<literallayout>@@#user-manual https://www.privoxy.org/user-manual/</literallayout>]]>
308 <!-- ~~~~~ New section ~~~~~ -->
309 <sect3 renderas="sect4" id="trust-info-url"><title>trust-info-url</title>
313 <term>Specifies:</term>
316 A URL to be displayed in the error page that users will see if access to an untrusted page is denied.
321 <term>Type of value:</term>
327 <term>Default value:</term>
329 <para><emphasis>Unset</emphasis></para>
333 <term>Effect if unset:</term>
336 No links are displayed on the "untrusted" error page.
344 The value of this option only matters if the experimental trust mechanism has been
345 activated. (See <link linkend="trustfile"><emphasis>trustfile</emphasis></link> below.)
348 If you use the trust mechanism, it is a good idea to write up some on-line
349 documentation about your trust policy and to specify the URL(s) here.
350 Use multiple times for multiple URLs.
353 The URL(s) should be added to the trustfile as well, so users don't end up
354 locked out from the information on why they were locked out in the first place!
360 <![%config-file;[<literallayout>@@#trust-info-url http://www.example.com/why_we_block.html</literallayout>]]>
361 <![%config-file;[<literallayout>@@#trust-info-url http://www.example.com/what_we_allow.html</literallayout>]]>
365 <!-- ~~~~~ New section ~~~~~ -->
366 <sect3 renderas="sect4" id="admin-address"><title>admin-address</title>
370 <term>Specifies:</term>
373 An email address to reach the <application>Privoxy</application> administrator.
378 <term>Type of value:</term>
380 <para>Email address</para>
384 <term>Default value:</term>
386 <para><emphasis>Unset</emphasis></para>
390 <term>Effect if unset:</term>
393 No email address is displayed on error pages and the CGI user interface.
401 If both <literal>admin-address</literal> and <literal>proxy-info-url</literal>
402 are unset, the whole "Local Privoxy Support" box on all generated pages will
409 <![%config-file;[<literallayout>@@#admin-address privoxy-admin@example.com</literallayout>]]>
413 <!-- ~~~~~ New section ~~~~~ -->
414 <sect3 renderas="sect4" id="proxy-info-url"><title>proxy-info-url</title>
418 <term>Specifies:</term>
421 A URL to documentation about the local <application>Privoxy</application> setup,
422 configuration or policies.
427 <term>Type of value:</term>
433 <term>Default value:</term>
435 <para><emphasis>Unset</emphasis></para>
439 <term>Effect if unset:</term>
442 No link to local documentation is displayed on error pages and the CGI user interface.
450 If both <literal>admin-address</literal> and <literal>proxy-info-url</literal>
451 are unset, the whole "Local Privoxy Support" box on all generated pages will
455 This URL shouldn't be blocked ;-)
461 <![%config-file;[<literallayout>@@#proxy-info-url http://www.example.com/proxy-service.html</literallayout>]]>
465 <!-- ~ End section ~ -->
469 <!-- ~~~~~ New section ~~~~~ -->
471 <sect2 id="conf-log-loc">
472 <title>Configuration and Log File Locations</title>
475 <application>Privoxy</application> can (and normally does) use a number of
476 other files for additional configuration, help and logging.
477 This section of the configuration file tells <application>Privoxy</application>
478 where to find those other files.
482 The user running <application>Privoxy</application>, must have read
483 permission for all configuration files, and write permission to any files
484 that would be modified, such as log files and actions files.
488 <!-- ~~~~~ New section ~~~~~ -->
489 <sect3 renderas="sect4" id="confdir"><title>confdir</title>
493 <term>Specifies:</term>
495 <para>The directory where the other configuration files are located.</para>
499 <term>Type of value:</term>
501 <para>Path name</para>
505 <term>Default value:</term>
507 <para>/etc/privoxy (Unix) <emphasis>or</emphasis> <application>Privoxy</application> installation dir (Windows) </para>
511 <term>Effect if unset:</term>
513 <para><emphasis>Mandatory</emphasis></para>
520 No trailing <quote><literal>/</literal></quote>, please.
526 <![%config-file;[<literallayout>@@confdir .</literallayout>]]>
529 <!-- ~~~~~ New section ~~~~~ -->
530 <sect3 renderas="sect4" id="templdir"><title>templdir</title>
534 <term>Specifies:</term>
536 <para>An alternative directory where the templates are loaded from.</para>
540 <term>Type of value:</term>
542 <para>Path name</para>
546 <term>Default value:</term>
552 <term>Effect if unset:</term>
554 <para>The templates are assumed to be located in confdir/template.</para>
561 <application>Privoxy's</application> original templates are usually
562 overwritten with each update. Use this option to relocate customized
563 templates that should be kept. As template variables might change
564 between updates, you shouldn't expect templates to work with
565 <application>Privoxy</application> releases other than the one
566 they were part of, though.
572 <![%config-file;[<literallayout>@@#templdir .</literallayout>]]>
576 <!-- ~~~~~ New section ~~~~~ -->
577 <sect3 renderas="sect4" id="temporary-directory"><title>temporary-directory</title>
581 <term>Specifies:</term>
583 <para>A directory where Privoxy can create temporary files.</para>
587 <term>Type of value:</term>
589 <para>Path name</para>
593 <term>Default value:</term>
599 <term>Effect if unset:</term>
601 <para>No temporary files are created, external filters don't work.</para>
608 To execute <literal><ulink url="actions-file.html#EXTERNAL-FILTER">external filters</ulink></literal>,
609 <application>Privoxy</application> has to create temporary files.
610 This directive specifies the directory the temporary files should
614 It should be a directory only <application>Privoxy</application>
615 (and trusted users) can access.
621 <![%config-file;[<literallayout>@@#temporary-directory .</literallayout>]]>
625 <!-- ~~~~~ New section ~~~~~ -->
626 <sect3 renderas="sect4" id="logdir"><title>logdir</title>
630 <term>Specifies:</term>
633 The directory where all logging takes place
634 (i.e. where the <filename>logfile</filename> is located).
639 <term>Type of value:</term>
641 <para>Path name</para>
645 <term>Default value:</term>
647 <para>/var/log/privoxy (Unix) <emphasis>or</emphasis> <application>Privoxy</application> installation dir (Windows) </para>
651 <term>Effect if unset:</term>
653 <para><emphasis>Mandatory</emphasis></para>
660 No trailing <quote><literal>/</literal></quote>, please.
666 <![%config-file;[<literallayout>@@logdir .</literallayout>]]>
670 <!-- ~~~~~ New section ~~~~~ -->
671 <sect3 renderas="sect4" id="actionsfile"><title>
674 <anchor id="default.action">
675 <anchor id="standard.action">
676 <anchor id="user.action">
677 <!-- Note: slightly modified this section 04/28/02, hal. See NOTE. -->
680 <term>Specifies:</term>
683 The <link linkend="actions-file">actions file(s)</link> to use
688 <term>Type of value:</term>
690 <para>Complete file name, relative to <literal>confdir</literal></para>
694 <term>Default values:</term>
698 <msgtext><literallayout> match-all.action # Actions that are applied to all sites and maybe overruled later on.</literallayout></msgtext>
701 <msgtext><literallayout> default.action # Main actions file</literallayout></msgtext>
704 <msgtext><literallayout> user.action # User customizations</literallayout></msgtext>
710 <term>Effect if unset:</term>
713 No actions are taken at all. More or less neutral proxying.
721 Multiple <literal>actionsfile</literal> lines are permitted, and are in fact recommended!
724 The default values are <filename>default.action</filename>, which is the
725 <quote>main</quote> actions file maintained by the developers, and
726 <filename>user.action</filename>, where you can make your personal additions.
729 Actions files contain all the per site and per URL configuration for
730 ad blocking, cookie management, privacy considerations, etc.
736 <!-- NOTE: alternate markup to make a simpler list doesn't work due to -->
737 <!-- html -> text conversion, blah -->
738 <![%config-file;[<literallayout>@@actionsfile match-all.action # Actions that are applied to all sites and maybe overruled later on.</literallayout>]]>
739 <![%config-file;[<literallayout>@@actionsfile default.action # Main actions file</literallayout>]]>
741 XXX: Like user.filter, user.action should probably be commented out
742 by default as not all packages install it into the default directory.
745 <![%config-file;[<literallayout>@@actionsfile user.action # User customizations</literallayout>]]>
748 <!-- ~~~~~ New section ~~~~~ -->
749 <sect3 renderas="sect4" id="filterfile"><title>filterfile</title>
750 <anchor id="default.filter">
753 <term>Specifies:</term>
756 The <link linkend="filter-file">filter file(s)</link> to use
761 <term>Type of value:</term>
763 <para>File name, relative to <literal>confdir</literal></para>
767 <term>Default value:</term>
769 <para>default.filter (Unix) <emphasis>or</emphasis> default.filter.txt (Windows)</para>
773 <term>Effect if unset:</term>
776 No textual content filtering takes place, i.e. all
777 <literal>+<link linkend="filter">filter</link>{<replaceable class="parameter">name</replaceable>}</literal>
778 actions in the actions files are turned neutral.
786 Multiple <literal>filterfile</literal> lines are permitted.
789 The <link linkend="filter-file">filter files</link> contain content modification
790 rules that use <link linkend="regex">regular expressions</link>. These rules permit
791 powerful changes on the content of Web pages, and optionally the headers
792 as well, e.g., you could try to disable your favorite JavaScript annoyances,
793 re-write the actual displayed text, or just have some fun
794 playing buzzword bingo with web pages.
798 <literal>+<link linkend="filter">filter</link>{<replaceable class="parameter">name</replaceable>}</literal>
799 actions rely on the relevant filter (<replaceable class="parameter">name</replaceable>)
800 to be defined in a filter file!
803 A pre-defined filter file called <filename>default.filter</filename> that contains
804 a number of useful filters for common problems is included in the distribution.
805 See the section on the <literal><link linkend="filter">filter</link></literal>
809 It is recommended to place any locally adapted filters into a separate
810 file, such as <filename>user.filter</filename>.
816 <![%config-file;[<literallayout>@@filterfile default.filter</literallayout>]]>
817 <![%config-file;[<literallayout>@@filterfile user.filter # User customizations</literallayout>]]>
821 <!-- ~~~~~ New section ~~~~~ -->
822 <sect3 renderas="sect4" id="logfile"><title>logfile</title>
826 <term>Specifies:</term>
834 <term>Type of value:</term>
836 <para>File name, relative to <literal>logdir</literal></para>
840 <term>Default value:</term>
842 <para><emphasis>Unset (commented out)</emphasis>. When activated: logfile (Unix) <emphasis>or</emphasis> privoxy.log (Windows).</para>
846 <term>Effect if unset:</term>
849 No logfile is written.
857 The logfile is where all logging and error messages are written. The level
858 of detail and number of messages are set with the <literal>debug</literal>
859 option (see below). The logfile can be useful for tracking down a problem with
860 <application>Privoxy</application> (e.g., it's not blocking an ad you
861 think it should block) and it can help you to monitor what your browser
865 Depending on the debug options below, the logfile may be a privacy risk
866 if third parties can get access to it. As most users will never look
867 at it, <application>Privoxy</application> only logs fatal errors by default.
870 For most troubleshooting purposes, you will have to change that,
871 please refer to the debugging section for details.
874 Any log files must be writable by whatever user <application>Privoxy</application>
875 is being run as (on Unix, default user id is <quote>privoxy</quote>).
878 To prevent the logfile from growing indefinitely, it is recommended to
879 periodically rotate or shorten it. Many operating systems support log
880 rotation out of the box, some require additional software to do it.
881 For details, please refer to the documentation for your operating system.
887 <![%config-file;[<literallayout>@@logfile logfile</literallayout>]]>
891 <!-- ~~~~~ New section ~~~~~ -->
892 <sect3 renderas="sect4" id="trustfile"><title>trustfile</title>
895 <term>Specifies:</term>
898 The name of the trust file to use
903 <term>Type of value:</term>
905 <para>File name, relative to <literal>confdir</literal></para>
909 <term>Default value:</term>
911 <para><emphasis>Unset (commented out)</emphasis>. When activated: trust (Unix) <emphasis>or</emphasis> trust.txt (Windows)</para>
915 <term>Effect if unset:</term>
918 The entire trust mechanism is disabled.
926 The trust mechanism is an experimental feature for building white-lists and should
927 be used with care. It is <emphasis>NOT</emphasis> recommended for the casual user.
930 If you specify a trust file, <application>Privoxy</application> will only allow
931 access to sites that are specified in the trustfile. Sites can be listed
935 Prepending a <literal>~</literal> character limits access to this site
936 only (and any sub-paths within this site), e.g.
937 <literal>~www.example.com</literal> allows access to
938 <literal>~www.example.com/features/news.html</literal>, etc.
941 Or, you can designate sites as <emphasis>trusted referrers</emphasis>, by
942 prepending the name with a <literal>+</literal> character. The effect is that
943 access to untrusted sites will be granted -- but only if a link from this
944 trusted referrer was used to get there. The link target will then be added
945 to the <quote>trustfile</quote> so that future, direct accesses will be
946 granted. Sites added via this mechanism do not become trusted referrers
947 themselves (i.e. they are added with a <literal>~</literal> designation).
948 There is a limit of 512 such entries, after which new entries will not be
952 If you use the <literal>+</literal> operator in the trust file, it may grow
953 considerably over time.
956 It is recommended that <application>Privoxy</application> be compiled with
957 the <literal>--disable-force</literal>, <literal>--disable-toggle</literal> and
958 <literal> --disable-editor</literal> options, if this feature is to be
962 Possible applications include limiting Internet access for children.
969 <![%config-file;[<literallayout>@@#trustfile trust</literallayout>]]>
973 <!-- ~ End section ~ -->
975 <!-- ~~~~~ New section ~~~~~ -->
976 <sect2 id="debugging">
977 <title>Debugging</title>
980 These options are mainly useful when tracing a problem.
981 Note that you might also want to invoke
982 <application>Privoxy</application> with the <literal>--no-daemon</literal>
983 command line option when debugging.
986 <sect3 renderas="sect4" id="debug"><title>debug</title>
990 <term>Specifies:</term>
993 Key values that determine what information gets logged.
998 <term>Type of value:</term>
1000 <para>Integer values</para>
1004 <term>Default value:</term>
1006 <para>0 (i.e.: only fatal errors (that cause Privoxy to exit) are logged)</para>
1010 <term>Effect if unset:</term>
1013 Default value is used (see above).
1021 The available debug levels are:
1024 debug 1 # Log the destination for each request &my-app; let through. See also debug 1024.
1025 debug 2 # show each connection status
1026 debug 4 # show I/O status
1027 debug 8 # show header parsing
1028 debug 16 # log all data written to the network
1029 debug 32 # debug force feature
1030 debug 64 # debug regular expression filters
1031 debug 128 # debug redirects
1032 debug 256 # debug GIF de-animation
1033 debug 512 # Common Log Format
1034 debug 1024 # Log the destination for requests &my-app; didn't let through, and the reason why.
1035 debug 2048 # CGI user interface
1036 debug 4096 # Startup banner and warnings.
1037 debug 8192 # Non-fatal errors
1038 debug 32768 # log all data read from the network
1039 debug 65536 # Log the applying actions
1042 To select multiple debug levels, you can either add them or use
1043 multiple <literal>debug</literal> lines.
1046 A debug level of 1 is informative because it will show you each request
1047 as it happens. <emphasis>1, 1024, 4096 and 8192 are recommended</emphasis>
1048 so that you will notice when things go wrong. The other levels are
1049 probably only of interest if you are hunting down a specific problem.
1050 They can produce a hell of an output (especially 16).
1053 If you are used to the more verbose settings, simply enable the debug lines
1057 If you want to use pure CLF (Common Log Format), you should set <quote>debug
1058 512</quote> <emphasis>ONLY</emphasis> and not enable anything else.
1061 <application>Privoxy</application> has a hard-coded limit for the
1062 length of log messages. If it's reached, messages are logged truncated
1063 and marked with <quote>... [too long, truncated]</quote>.
1066 Please don't file any support requests without trying to reproduce
1067 the problem with increased debug level first. Once you read the log
1068 messages, you may even be able to solve the problem on your own.
1074 <![%config-file;[<literallayout>@@#debug 1 # Log the destination for each request &my-app; let through.</literallayout>]]>
1075 <![%config-file;[<literallayout>@@#debug 1024 # Log the destination for requests &my-app; didn't let through, and the reason why.</literallayout>]]>
1076 <![%config-file;[<literallayout>@@#debug 4096 # Startup banner and warnings</literallayout>]]>
1077 <![%config-file;[<literallayout>@@#debug 8192 # Non-fatal errors</literallayout>]]>
1081 <!-- ~~~~~ New section ~~~~~ -->
1082 <sect3 renderas="sect4" id="single-threaded"><title>single-threaded</title>
1086 <term>Specifies:</term>
1089 Whether to run only one server thread.
1094 <term>Type of value:</term>
1096 <para><emphasis>1 or 0</emphasis></para>
1100 <term>Default value:</term>
1102 <para><emphasis>0</emphasis></para>
1106 <term>Effect if unset:</term>
1109 Multi-threaded (or, where unavailable: forked) operation, i.e. the ability to
1110 serve multiple requests simultaneously.
1118 This option is only there for debugging purposes.
1119 <emphasis>It will drastically reduce performance.</emphasis>
1125 <![%config-file;[<literallayout>@@#single-threaded 1</literallayout>]]>
1128 <!-- ~~~~~ New section ~~~~~ -->
1129 <sect3 renderas="sect4" id="hostname"><title>hostname</title>
1133 <term>Specifies:</term>
1136 The hostname shown on the CGI pages.
1141 <term>Type of value:</term>
1147 <term>Default value:</term>
1149 <para><emphasis>Unset</emphasis></para>
1153 <term>Effect if unset:</term>
1156 The hostname provided by the operating system is used.
1164 On some misconfigured systems resolving the hostname fails or
1165 takes too much time and slows Privoxy down. Setting a fixed hostname
1166 works around the problem.
1169 In other circumstances it might be desirable to show a hostname
1170 other than the one returned by the operating system. For example
1171 if the system has several different hostnames and you don't want
1172 to use the first one.
1175 Note that Privoxy does not validate the specified hostname value.
1181 <![%config-file;[<literallayout>@@#hostname hostname.example.org</literallayout>]]>
1186 <!-- ~ End section ~ -->
1189 <!-- ~~~~~ New section ~~~~~ -->
1190 <sect2 id="access-control">
1191 <title>Access Control and Security</title>
1194 This section of the config file controls the security-relevant aspects
1195 of <application>Privoxy</application>'s configuration.
1199 <!-- ~~~~~ New section ~~~~~ -->
1200 <sect3 renderas="sect4" id="listen-address"><title>listen-address</title>
1204 <term>Specifies:</term>
1207 The address and TCP port on which <application>Privoxy</application> will
1208 listen for client requests.
1213 <term>Type of value:</term>
1215 <para>[<replaceable class="parameter">IP-Address</replaceable>]:<replaceable class="parameter">Port</replaceable></para>
1216 <para>[<replaceable class="parameter">Hostname</replaceable>]:<replaceable class="parameter">Port</replaceable></para>
1221 <term>Default value:</term>
1223 <para>127.0.0.1:8118</para>
1227 <term>Effect if unset:</term>
1230 Bind to 127.0.0.1 (IPv4 localhost), port 8118. This is suitable and
1231 recommended for home users who run <application>Privoxy</application> on
1232 the same machine as their browser.
1240 You will need to configure your browser(s) to this proxy address and port.
1243 If you already have another service running on port 8118, or if you want to
1244 serve requests from other machines (e.g. on your local network) as well, you
1245 will need to override the default.
1248 You can use this statement multiple times to make
1249 <application>Privoxy</application> listen on more ports or more
1250 <abbrev>IP</abbrev> addresses. Suitable if your operating system does not
1251 support sharing <abbrev>IPv6</abbrev> and <abbrev>IPv4</abbrev> protocols
1255 If a hostname is used instead of an IP address, <application>Privoxy</application>
1256 will try to resolve it to an IP address and if there are multiple, use the first
1260 If the address for the hostname isn't already known on the system
1261 (for example because it's in /etc/hostname), this may result in DNS
1265 If the specified address isn't available on the system, or if the
1266 hostname can't be resolved, <application>Privoxy</application>
1270 IPv6 addresses containing colons have to be quoted by brackets.
1271 They can only be used if <application>Privoxy</application> has
1272 been compiled with IPv6 support. If you aren't sure if your version
1273 supports it, have a look at
1274 <literal>http://config.privoxy.org/show-status</literal>.
1277 Some operating systems will prefer IPv6 to IPv4 addresses even if the
1278 system has no IPv6 connectivity which is usually not expected by the user.
1279 Some even rely on DNS to resolve localhost which mean the "localhost" address
1280 used may not actually be local.
1283 It is therefore recommended to explicitly configure the intended IP address
1284 instead of relying on the operating system, unless there's a strong reason not to.
1287 If you leave out the address, <application>Privoxy</application> will bind to all
1288 IPv4 interfaces (addresses) on your machine and may become reachable from the
1289 Internet and/or the local network. Be aware that some GNU/Linux distributions
1290 modify that behaviour without updating the documentation. Check for non-standard
1291 patches if your <application>Privoxy</application> version behaves differently.
1294 If you configure <application>Privoxy</application> to be reachable from the
1295 network, consider using <link linkend="acls">access control lists</link>
1296 (ACL's, see below), and/or a firewall.
1299 If you open <application>Privoxy</application> to untrusted users, you will
1300 also want to make sure that the following actions are disabled: <literal><link
1301 linkend="enable-edit-actions">enable-edit-actions</link></literal> and
1302 <literal><link linkend="enable-remote-toggle">enable-remote-toggle</link></literal>
1307 <term>Example:</term>
1310 Suppose you are running <application>Privoxy</application> on
1311 a machine which has the address 192.168.0.1 on your local private network
1312 (192.168.0.0) and has another outside connection with a different address.
1313 You want it to serve requests from inside only:
1316 listen-address 192.168.0.1:8118
1319 Suppose you are running <application>Privoxy</application> on an
1320 IPv6-capable machine and you want it to listen on the IPv6 address
1321 of the loopback device:
1324 listen-address [::1]:8118
1330 <![%config-file;[<literallayout>@@listen-address 127.0.0.1:8118</literallayout>]]>
1334 <!-- ~~~~~ New section ~~~~~ -->
1335 <sect3 renderas="sect4" id="toggle"><title>toggle</title>
1339 <term>Specifies:</term>
1342 Initial state of "toggle" status
1347 <term>Type of value:</term>
1353 <term>Default value:</term>
1359 <term>Effect if unset:</term>
1362 Act as if toggled on
1370 If set to 0, <application>Privoxy</application> will start in
1371 <quote>toggled off</quote> mode, i.e. mostly behave like a normal,
1372 content-neutral proxy with both ad blocking and content filtering
1373 disabled. See <literal>enable-remote-toggle</literal> below.
1379 <![%config-file;[<literallayout>@@toggle 1</literallayout>]]>
1383 <!-- ~~~~~ New section ~~~~~ -->
1384 <sect3 renderas="sect4" id="enable-remote-toggle"><title>enable-remote-toggle</title>
1387 <term>Specifies:</term>
1390 Whether or not the <ulink url="http://config.privoxy.org/toggle">web-based toggle
1391 feature</ulink> may be used
1396 <term>Type of value:</term>
1402 <term>Default value:</term>
1408 <term>Effect if unset:</term>
1411 The web-based toggle feature is disabled.
1419 When toggled off, <application>Privoxy</application> mostly acts like a normal,
1420 content-neutral proxy, i.e. doesn't block ads or filter content.
1423 Access to the toggle feature can <emphasis>not</emphasis> be
1424 controlled separately by <quote>ACLs</quote> or HTTP authentication,
1425 so that everybody who can access <application>Privoxy</application> (see
1426 <quote>ACLs</quote> and <literal>listen-address</literal> above) can
1427 toggle it for all users. So this option is <emphasis>not recommended</emphasis>
1428 for multi-user environments with untrusted users.
1431 Note that malicious client side code (e.g Java) is also
1432 capable of using this option.
1435 As a lot of <application>Privoxy</application> users don't read
1436 documentation, this feature is disabled by default.
1439 Note that you must have compiled <application>Privoxy</application> with
1440 support for this feature, otherwise this option has no effect.
1446 <![%config-file;[<literallayout>@@enable-remote-toggle 0</literallayout>]]>
1450 <!-- ~~~~~ New section ~~~~~ -->
1451 <sect3 renderas="sect4" id="enable-remote-http-toggle"><title>enable-remote-http-toggle</title>
1454 <term>Specifies:</term>
1457 Whether or not Privoxy recognizes special HTTP headers to change its behaviour.
1462 <term>Type of value:</term>
1468 <term>Default value:</term>
1474 <term>Effect if unset:</term>
1477 Privoxy ignores special HTTP headers.
1485 When toggled on, the client can change <application>Privoxy's</application>
1486 behaviour by setting special HTTP headers. Currently the only supported
1487 special header is <quote>X-Filter: No</quote>, to disable filtering for
1488 the ongoing request, even if it is enabled in one of the action files.
1491 This feature is disabled by default. If you are using
1492 <application>Privoxy</application> in a environment with trusted clients,
1493 you may enable this feature at your discretion. Note that malicious client
1494 side code (e.g Java) is also capable of using this feature.
1497 This option will be removed in future releases as it has been obsoleted
1498 by the more general header taggers.
1504 <![%config-file;[<literallayout>@@enable-remote-http-toggle 0</literallayout>]]>
1508 <!-- ~~~~~ New section ~~~~~ -->
1509 <sect3 renderas="sect4" id="enable-edit-actions"><title>enable-edit-actions</title>
1512 <term>Specifies:</term>
1515 Whether or not the <ulink url="http://config.privoxy.org/show-status">web-based actions
1516 file editor</ulink> may be used
1521 <term>Type of value:</term>
1527 <term>Default value:</term>
1533 <term>Effect if unset:</term>
1536 The web-based actions file editor is disabled.
1544 Access to the editor can <emphasis>not</emphasis> be
1545 controlled separately by <quote>ACLs</quote> or HTTP authentication,
1546 so that everybody who can access <application>Privoxy</application> (see
1547 <quote>ACLs</quote> and <literal>listen-address</literal> above) can
1548 modify its configuration for all users.
1551 This option is <emphasis>not recommended</emphasis> for environments
1552 with untrusted users and as a lot of <application>Privoxy</application>
1553 users don't read documentation, this feature is disabled by default.
1556 Note that malicious client side code (e.g Java) is also
1557 capable of using the actions editor and you shouldn't enable
1558 this options unless you understand the consequences and are
1559 sure your browser is configured correctly.
1562 Note that you must have compiled <application>Privoxy</application> with
1563 support for this feature, otherwise this option has no effect.
1569 <![%config-file;[<literallayout>@@enable-edit-actions 0</literallayout>]]>
1573 <sect3 renderas="sect4" id="enforce-blocks"><title>enforce-blocks</title>
1576 <term>Specifies:</term>
1579 Whether the user is allowed to ignore blocks and can <quote>go there anyway</quote>.
1584 <term>Type of value:</term>
1587 <replaceable>0 or 1</replaceable>
1592 <term>Default value:</term>
1594 <para><emphasis>0</emphasis></para>
1598 <term>Effect if unset:</term>
1601 Blocks are not enforced.
1609 <application>Privoxy</application> is mainly used to block and filter
1610 requests as a service to the user, for example to block ads and other
1611 junk that clogs the pipes. <application>Privoxy's</application> configuration
1612 isn't perfect and sometimes innocent pages are blocked. In this situation it
1613 makes sense to allow the user to enforce the request and have
1614 <application>Privoxy</application> ignore the block.
1617 In the default configuration <application>Privoxy's</application>
1618 <quote>Blocked</quote> page contains a <quote>go there anyway</quote>
1619 link to adds a special string (the force prefix) to the request URL.
1620 If that link is used, <application>Privoxy</application> will
1621 detect the force prefix, remove it again and let the request pass.
1624 Of course <application>Privoxy</application> can also be used to enforce
1625 a network policy. In that case the user obviously should not be able to
1626 bypass any blocks, and that's what the <quote>enforce-blocks</quote>
1627 option is for. If it's enabled, <application>Privoxy</application> hides
1628 the <quote>go there anyway</quote> link. If the user adds the force
1629 prefix by hand, it will not be accepted and the circumvention attempt
1635 <term>Examples:</term>
1643 <![%config-file;[<literallayout>@@enforce-blocks 0</literallayout>]]>
1647 <!-- ~~~~~ New section ~~~~~ -->
1648 <sect3 renderas="sect4" id="acls"><title>
1649 ACLs: permit-access and deny-access</title>
1650 <anchor id="permit-access">
1651 <anchor id="deny-access">
1655 <term>Specifies:</term>
1658 Who can access what.
1663 <term>Type of value:</term>
1666 <replaceable class="parameter">src_addr</replaceable>[:<replaceable class="parameter">port</replaceable>][/<replaceable class="parameter">src_masklen</replaceable>]
1667 [<replaceable class="parameter">dst_addr</replaceable>[:<replaceable class="parameter">port</replaceable>][/<replaceable class="parameter">dst_masklen</replaceable>]]
1670 Where <replaceable class="parameter">src_addr</replaceable> and
1671 <replaceable class="parameter">dst_addr</replaceable> are IPv4 addresses in dotted decimal notation or valid
1672 DNS names, <replaceable class="parameter">port</replaceable> is a port
1673 number, and <replaceable class="parameter">src_masklen</replaceable> and
1674 <replaceable class="parameter">dst_masklen</replaceable> are subnet masks in CIDR notation, i.e. integer
1675 values from 2 to 30 representing the length (in bits) of the network address. The masks and the whole
1676 destination part are optional.
1679 If your system implements
1680 <ulink url="http://tools.ietf.org/html/rfc3493">RFC 3493</ulink>, then
1681 <replaceable class="parameter">src_addr</replaceable> and <replaceable
1682 class="parameter">dst_addr</replaceable> can be IPv6 addresses delimeted by
1683 brackets, <replaceable class="parameter">port</replaceable> can be a number
1684 or a service name, and
1685 <replaceable class="parameter">src_masklen</replaceable> and
1686 <replaceable class="parameter">dst_masklen</replaceable> can be a number
1692 <term>Default value:</term>
1694 <para><emphasis>Unset</emphasis></para>
1696 If no <replaceable class="parameter">port</replaceable> is specified,
1697 any port will match. If no <replaceable class="parameter">src_masklen</replaceable> or
1698 <replaceable class="parameter">src_masklen</replaceable> is given, the complete IP
1699 address has to match (i.e. 32 bits for IPv4 and 128 bits for IPv6).
1704 <term>Effect if unset:</term>
1707 Don't restrict access further than implied by <literal>listen-address</literal>
1715 Access controls are included at the request of ISPs and systems
1716 administrators, and <emphasis>are not usually needed by individual users</emphasis>.
1717 For a typical home user, it will normally suffice to ensure that
1718 <application>Privoxy</application> only listens on the localhost
1719 (127.0.0.1) or internal (home) network address by means of the
1720 <link linkend="listen-address"><emphasis>listen-address</emphasis></link>
1724 Please see the warnings in the FAQ that <application>Privoxy</application>
1725 is not intended to be a substitute for a firewall or to encourage anyone
1726 to defer addressing basic security weaknesses.
1729 Multiple ACL lines are OK.
1730 If any ACLs are specified, <application>Privoxy</application> only talks
1731 to IP addresses that match at least one <literal>permit-access</literal> line
1732 and don't match any subsequent <literal>deny-access</literal> line. In other words, the
1733 last match wins, with the default being <literal>deny-access</literal>.
1736 If <application>Privoxy</application> is using a forwarder (see <literal>forward</literal> below)
1737 for a particular destination URL, the <replaceable class="parameter">dst_addr</replaceable>
1738 that is examined is the address of the forwarder and <emphasis>NOT</emphasis> the address
1739 of the ultimate target. This is necessary because it may be impossible for the local
1740 <application>Privoxy</application> to determine the IP address of the
1741 ultimate target (that's often what gateways are used for).
1744 You should prefer using IP addresses over DNS names, because the address lookups take
1745 time. All DNS names must resolve! You can <emphasis>not</emphasis> use domain patterns
1746 like <quote>*.org</quote> or partial domain names. If a DNS name resolves to multiple
1747 IP addresses, only the first one is used.
1750 Some systems allow IPv4 clients to connect to IPv6 server sockets.
1751 Then the client's IPv4 address will be translated by the system into
1752 IPv6 address space with special prefix ::ffff:0:0/96 (so called IPv4
1753 mapped IPv6 address). <application>Privoxy</application> can handle it
1754 and maps such ACL addresses automatically.
1757 Denying access to particular sites by ACL may have undesired side effects
1758 if the site in question is hosted on a machine which also hosts other sites
1764 <term>Examples:</term>
1767 Explicitly define the default behavior if no ACL and
1768 <literal>listen-address</literal> are set: <quote>localhost</quote>
1769 is OK. The absence of a <replaceable class="parameter">dst_addr</replaceable> implies that
1770 <emphasis>all</emphasis> destination addresses are OK:
1773 permit-access localhost
1776 Allow any host on the same class C subnet as www.privoxy.org access to
1777 nothing but www.example.com (or other domains hosted on the same system):
1780 permit-access www.privoxy.org/24 www.example.com/32
1783 Allow access from any host on the 26-bit subnet 192.168.45.64 to anywhere,
1784 with the exception that 192.168.45.73 may not access the IP address behind
1785 www.dirty-stuff.example.com:
1788 permit-access 192.168.45.64/26
1789 deny-access 192.168.45.73 www.dirty-stuff.example.com
1792 Allow access from the IPv4 network 192.0.2.0/24 even if listening on
1793 an IPv6 wild card address (not supported on all platforms):
1796 permit-access 192.0.2.0/24
1799 This is equivalent to the following line even if listening on an
1800 IPv4 address (not supported on all platforms):
1803 permit-access [::ffff:192.0.2.0]/120
1811 <!-- ~~~~~ New section ~~~~~ -->
1812 <sect3 renderas="sect4" id="buffer-limit"><title>buffer-limit</title>
1816 <term>Specifies:</term>
1819 Maximum size of the buffer for content filtering.
1824 <term>Type of value:</term>
1826 <para>Size in Kbytes</para>
1830 <term>Default value:</term>
1836 <term>Effect if unset:</term>
1839 Use a 4MB (4096 KB) limit.
1847 For content filtering, i.e. the <literal>+filter</literal> and
1848 <literal>+deanimate-gif</literal> actions, it is necessary that
1849 <application>Privoxy</application> buffers the entire document body.
1850 This can be potentially dangerous, since a server could just keep sending
1851 data indefinitely and wait for your RAM to exhaust -- with nasty consequences.
1855 When a document buffer size reaches the <literal>buffer-limit</literal>, it is
1856 flushed to the client unfiltered and no further attempt to
1857 filter the rest of the document is made. Remember that there may be multiple threads
1858 running, which might require up to <literal>buffer-limit</literal> Kbytes
1859 <emphasis>each</emphasis>, unless you have enabled <quote>single-threaded</quote>
1866 <![%config-file;[<literallayout>@@buffer-limit 4096</literallayout>]]>
1869 <!-- ~~~~~ New section ~~~~~ -->
1870 <sect3 renderas="sect4" id="enable-proxy-authentication-forwarding"><title>enable-proxy-authentication-forwarding</title>
1873 <term>Specifies:</term>
1876 Whether or not proxy authentication through &my-app; should work.
1881 <term>Type of value:</term>
1887 <term>Default value:</term>
1893 <term>Effect if unset:</term>
1896 Proxy authentication headers are removed.
1904 Privoxy itself does not support proxy authentication, but can
1905 allow clients to authenticate against Privoxy's parent proxy.
1908 By default Privoxy (3.0.21 and later) don't do that and remove
1909 Proxy-Authorization headers in requests and Proxy-Authenticate
1910 headers in responses to make it harder for malicious sites to
1911 trick inexperienced users into providing login information.
1914 If this option is enabled the headers are forwarded.
1917 Enabling this option is <emphasis>not recommended</emphasis> if there is
1918 no parent proxy that requires authentication or if the local network between
1919 Privoxy and the parent proxy isn't trustworthy. If proxy authentication is
1920 only required for some requests, it is recommended to use a client header filter
1921 to remove the authentication headers for requests where they aren't needed.
1927 <![%config-file;[<literallayout>@@enable-proxy-authentication-forwarding 0</literallayout>]]>
1930 <!-- ~~~~~ New section ~~~~~ -->
1931 <sect3 renderas="sect4" id="trusted-cgi-referer"><title>trusted-cgi-referer</title>
1934 <term>Specifies:</term>
1937 A trusted website or webpage whose links can be followed to reach sensitive CGI pages
1942 <term>Type of value:</term>
1944 <para>URL or URL prefix</para>
1948 <term>Default value:</term>
1954 <term>Effect if unset:</term>
1957 No external pages are considered trusted referers.
1965 Before &my-app; accepts configuration changes through CGI pages like
1966 <link linkend="client-specific-tag">client-tags</link> or the
1967 <link linkend="enable-remote-toggle">remote toggle</link>, it checks
1968 the Referer header to see if the request comes from a trusted source.
1971 By default only the webinterface domains
1972 <ulink url="http://config.privoxy.org/">config.privoxy.org</ulink>
1974 <ulink url="http://p.p/">p.p</ulink>
1975 are considered trustworthy.
1976 Requests originating from other domains are rejected to prevent
1977 third-parties from modifiying Privoxy's state by e.g. embedding
1978 images that result in CGI requests.
1981 In some environments it may be desirable to embed links to CGI pages
1982 on external pages, for example on an Intranet homepage the Privoxy admin
1986 The <quote>trusted-cgi-referer</quote> option can be used to add that page,
1987 or the whole domain, as trusted source so the resulting requests aren't
1989 Requests are accepted if the specified trusted-cgi-refer is the prefix
1994 Declaring pages the admin doesn't control trustworthy may allow
1995 malicious third parties to modify Privoxy's internal state against
1996 the user's wishes and without the user's knowledge.
2003 <![%config-file;[<literallayout>@@trusted-cgi-referer http://www.example.org/local-privoxy-control-page</literallayout>]]>
2008 <!-- ~ End section ~ -->
2011 <!-- ~~~~~ New section ~~~~~ -->
2013 <sect2 id="forwarding">
2014 <title>Forwarding</title>
2017 This feature allows routing of HTTP requests through a chain of
2021 Forwarding can be used to chain Privoxy with a caching proxy to speed
2022 up browsing. Using a parent proxy may also be necessary if the machine
2023 that <application>Privoxy</application> runs on has no direct Internet access.
2026 Note that parent proxies can severely decrease your privacy level.
2027 For example a parent proxy could add your IP address to the request
2028 headers and if it's a caching proxy it may add the <quote>Etag</quote>
2029 header to revalidation requests again, even though you configured Privoxy
2030 to remove it. It may also ignore Privoxy's header time randomization and use the
2031 original values which could be used by the server as cookie replacement
2032 to track your steps between visits.
2036 Also specified here are SOCKS proxies. <application>Privoxy</application>
2037 supports the SOCKS 4 and SOCKS 4A protocols.
2040 <sect3 renderas="sect4" id="forward"><title>forward</title>
2043 <term>Specifies:</term>
2046 To which parent HTTP proxy specific requests should be routed.
2051 <term>Type of value:</term>
2054 <replaceable class="parameter">target_pattern</replaceable>
2055 <replaceable class="parameter">http_parent</replaceable>[:<replaceable class="parameter">port</replaceable>]
2058 where <replaceable class="parameter">target_pattern</replaceable> is a <link linkend="af-patterns">URL pattern</link>
2059 that specifies to which requests (i.e. URLs) this forward rule shall apply. Use <literal>/</literal> to
2060 denote <quote>all URLs</quote>.
2061 <replaceable class="parameter">http_parent</replaceable>[:<replaceable class="parameter">port</replaceable>]
2062 is the DNS name or IP address of the parent HTTP proxy through which the requests should be forwarded,
2063 optionally followed by its listening port (default: 8000).
2064 Use a single dot (<literal>.</literal>) to denote <quote>no forwarding</quote>.
2069 <term>Default value:</term>
2071 <para><emphasis>Unset</emphasis></para>
2075 <term>Effect if unset:</term>
2078 Don't use parent HTTP proxies.
2086 If <replaceable class="parameter">http_parent</replaceable> is <quote>.</quote>, then requests are not
2087 forwarded to another HTTP proxy but are made directly to the web servers.
2090 <replaceable class="parameter">http_parent</replaceable> can be a
2091 numerical IPv6 address (if
2092 <ulink url="http://tools.ietf.org/html/rfc3493">RFC 3493</ulink> is
2093 implemented). To prevent clashes with the port delimiter, the whole IP
2094 address has to be put into brackets. On the other hand a <replaceable
2095 class="parameter">target_pattern</replaceable> containing an IPv6 address
2096 has to be put into angle brackets (normal brackets are reserved for
2097 regular expressions already).
2100 Multiple lines are OK, they are checked in sequence, and the last match wins.
2105 <term>Examples:</term>
2108 Everything goes to an example parent proxy, except SSL on port 443 (which it doesn't handle):
2111 forward / parent-proxy.example.org:8080
2115 Everything goes to our example ISP's caching proxy, except for requests
2116 to that ISP's sites:
2119 forward / caching-proxy.isp.example.net:8000
2120 forward .isp.example.net .
2123 Parent proxy specified by an IPv6 address:
2126 forward / [2001:DB8::1]:8000
2129 Suppose your parent proxy doesn't support IPv6:
2132 forward / parent-proxy.example.org:8000
2133 forward ipv6-server.example.org .
2134 forward <[2-3][0-9a-f][0-9a-f][0-9a-f]:*> .
2142 <!-- ~~~~~ New section ~~~~~ -->
2143 <sect3 renderas="sect4" id="socks"><title>
2144 forward-socks4, forward-socks4a, forward-socks5 and forward-socks5t</title>
2145 <anchor id="forward-socks4">
2146 <anchor id="forward-socks4a">
2150 <term>Specifies:</term>
2153 Through which SOCKS proxy (and optionally to which parent HTTP proxy) specific requests should be routed.
2158 <term>Type of value:</term>
2161 <replaceable class="parameter">target_pattern</replaceable>
2162 <replaceable class="parameter">socks_proxy</replaceable>[:<replaceable class="parameter">port</replaceable>]
2163 <replaceable class="parameter">http_parent</replaceable>[:<replaceable class="parameter">port</replaceable>]
2166 where <replaceable class="parameter">target_pattern</replaceable> is a
2167 <link linkend="af-patterns">URL pattern</link> that specifies to which
2168 requests (i.e. URLs) this forward rule shall apply. Use <literal>/</literal> to
2169 denote <quote>all URLs</quote>. <replaceable class="parameter">http_parent</replaceable>
2170 and <replaceable class="parameter">socks_proxy</replaceable>
2171 are IP addresses in dotted decimal notation or valid DNS names
2172 (<replaceable class="parameter">http_parent</replaceable>
2173 may be <quote>.</quote> to denote <quote>no HTTP forwarding</quote>), and the optional
2174 <replaceable class="parameter">port</replaceable> parameters are TCP ports,
2175 i.e. integer values from 1 to 65535
2180 <term>Default value:</term>
2182 <para><emphasis>Unset</emphasis></para>
2186 <term>Effect if unset:</term>
2189 Don't use SOCKS proxies.
2197 Multiple lines are OK, they are checked in sequence, and the last match wins.
2200 The difference between <literal>forward-socks4</literal> and <literal>forward-socks4a</literal>
2201 is that in the SOCKS 4A protocol, the DNS resolution of the target hostname happens on the SOCKS
2202 server, while in SOCKS 4 it happens locally.
2205 With <literal>forward-socks5</literal> the DNS resolution will happen on the remote server as well.
2208 <literal>forward-socks5t</literal> works like vanilla <literal>forward-socks5</literal> but
2209 lets &my-app; additionally use Tor-specific SOCKS extensions. Currently the only supported
2210 SOCKS extension is optimistic data which can reduce the latency for the first request made
2211 on a newly created connection.
2214 <replaceable class="parameter">socks_proxy</replaceable> and
2215 <replaceable class="parameter">http_parent</replaceable> can be a
2216 numerical IPv6 address (if
2217 <ulink url="http://tools.ietf.org/html/rfc3493">RFC 3493</ulink> is
2218 implemented). To prevent clashes with the port delimiter, the whole IP
2219 address has to be put into brackets. On the other hand a <replaceable
2220 class="parameter">target_pattern</replaceable> containing an IPv6 address
2221 has to be put into angle brackets (normal brackets are reserved for
2222 regular expressions already).
2225 If <replaceable class="parameter">http_parent</replaceable> is <quote>.</quote>, then requests are not
2226 forwarded to another HTTP proxy but are made (HTTP-wise) directly to the web servers, albeit through
2232 <term>Examples:</term>
2235 From the company example.com, direct connections are made to all
2236 <quote>internal</quote> domains, but everything outbound goes through
2237 their ISP's proxy by way of example.com's corporate SOCKS 4A gateway to
2241 forward-socks4a / socks-gw.example.com:1080 www-cache.isp.example.net:8080
2242 forward .example.com .
2245 A rule that uses a SOCKS 4 gateway for all destinations but no HTTP parent looks like this:
2248 forward-socks4 / socks-gw.example.com:1080 .
2252 To chain Privoxy and Tor, both running on the same system, you would use
2256 forward-socks5t / 127.0.0.1:9050 .
2259 Note that if you got Tor through one of the bundles, you may
2260 have to change the port from 9050 to 9150 (or even another one).
2261 For details, please check the documentation on the
2262 <ulink url="https://torproject.org/">Tor website</ulink>.
2265 The public <application>Tor</application> network can't be used to
2266 reach your local network, if you need to access local servers you
2267 therefore might want to make some exceptions:
2270 forward 192.168.*.*/ .
2272 forward 127.*.*.*/ .
2275 Unencrypted connections to systems in these address ranges will
2276 be as (un)secure as the local network is, but the alternative is that you
2277 can't reach the local network through <application>Privoxy</application>
2278 at all. Of course this may actually be desired and there is no reason
2279 to make these exceptions if you aren't sure you need them.
2282 If you also want to be able to reach servers in your local network by
2283 using their names, you will need additional exceptions that look like
2287 forward localhost/ .
2295 <![%user-man;[ <!-- not included in config due to length -->
2296 <!-- ~~~~~ New section ~~~~~ -->
2297 <sect3 renderas="sect4" id="advanced-forwarding-examples"><title>Advanced Forwarding Examples</title>
2300 If you have links to multiple ISPs that provide various special content
2301 only to their subscribers, you can configure multiple <application>Privoxies</application>
2302 which have connections to the respective ISPs to act as forwarders to each other, so that
2303 <emphasis>your</emphasis> users can see the internal content of all ISPs.
2307 Assume that host-a has a PPP connection to isp-a.example.net. And host-b has a PPP connection to
2308 isp-b.example.org. Both run <application>Privoxy</application>. Their forwarding
2309 configuration can look like this:
2318 forward .isp-b.example.net host-b:8118
2327 forward .isp-a.example.org host-a:8118
2331 Now, your users can set their browser's proxy to use either
2332 host-a or host-b and be able to browse the internal content
2333 of both isp-a and isp-b.
2337 If you intend to chain <application>Privoxy</application> and
2338 <application>squid</application> locally, then chaining as
2339 <literal>browser -> squid -> privoxy</literal> is the recommended way.
2343 Assuming that <application>Privoxy</application> and <application>squid</application>
2344 run on the same box, your <application>squid</application> configuration could then look like this:
2348 # Define Privoxy as parent proxy (without ICP)
2349 cache_peer 127.0.0.1 parent 8118 7 no-query
2351 # Define ACL for protocol FTP
2354 # Do not forward FTP requests to Privoxy
2355 always_direct allow ftp
2357 # Forward all the rest to Privoxy
2358 never_direct allow all</screen>
2361 You would then need to change your browser's proxy settings to <application>squid</application>'s address and port.
2362 Squid normally uses port 3128. If unsure consult <literal>http_port</literal> in <filename>squid.conf</filename>.
2366 You could just as well decide to only forward requests you suspect
2367 of leading to Windows executables through a virus-scanning parent proxy,
2368 say, on <literal>antivir.example.com</literal>, port 8010:
2373 forward /.*\.(exe|com|dll|zip)$ antivir.example.com:8010</screen>
2378 <sect3 renderas="sect4" id="forwarded-connect-retries"><title>forwarded-connect-retries</title>
2381 <term>Specifies:</term>
2384 How often Privoxy retries if a forwarded connection request fails.
2389 <term>Type of value:</term>
2392 <replaceable class="parameter">Number of retries.</replaceable>
2397 <term>Default value:</term>
2399 <para><emphasis>0</emphasis></para>
2403 <term>Effect if unset:</term>
2406 Connections forwarded through other proxies are treated like direct connections and no retry attempts are made.
2414 <replaceable class="parameter">forwarded-connect-retries</replaceable> is mainly interesting
2415 for socks4a connections, where <application>Privoxy</application> can't detect why the connections failed.
2416 The connection might have failed because of a DNS timeout in which case a retry makes sense,
2417 but it might also have failed because the server doesn't exist or isn't reachable. In this
2418 case the retry will just delay the appearance of Privoxy's error message.
2421 Note that in the context of this option, <quote>forwarded connections</quote> includes all connections
2422 that Privoxy forwards through other proxies. This option is not limited to the HTTP CONNECT method.
2425 Only use this option, if you are getting lots of forwarding-related error messages
2426 that go away when you try again manually. Start with a small value and check Privoxy's
2427 logfile from time to time, to see how many retries are usually needed.
2432 <term>Examples:</term>
2435 forwarded-connect-retries 1
2440 <![%config-file;[<literallayout>@@forwarded-connect-retries 0</literallayout>]]>
2446 <title>Miscellaneous</title>
2448 <sect3 renderas="sect4" id="accept-intercepted-requests"><title>accept-intercepted-requests</title>
2451 <term>Specifies:</term>
2454 Whether intercepted requests should be treated as valid.
2459 <term>Type of value:</term>
2462 <replaceable>0 or 1</replaceable>
2467 <term>Default value:</term>
2469 <para><emphasis>0</emphasis></para>
2473 <term>Effect if unset:</term>
2476 Only proxy requests are accepted, intercepted requests are treated as invalid.
2484 If you don't trust your clients and want to force them
2485 to use <application>Privoxy</application>, enable this
2486 option and configure your packet filter to redirect outgoing
2487 HTTP connections into <application>Privoxy</application>.
2490 Note that intercepting encrypted connections (HTTPS) isn't supported.
2493 Make sure that <application>Privoxy's</application> own requests
2494 aren't redirected as well. Additionally take care that
2495 <application>Privoxy</application> can't intentionally connect
2496 to itself, otherwise you could run into redirection loops if
2497 <application>Privoxy's</application> listening port is reachable
2498 by the outside or an attacker has access to the pages you visit.
2501 If you are running Privoxy as intercepting proxy without being
2502 able to intercept all client requests you may want to adjust
2503 the CGI templates to make sure they don't reference content from
2509 <term>Examples:</term>
2512 accept-intercepted-requests 1
2517 <![%config-file;[<literallayout>@@accept-intercepted-requests 0</literallayout>]]>
2520 <sect3 renderas="sect4" id="allow-cgi-request-crunching"><title>allow-cgi-request-crunching</title>
2523 <term>Specifies:</term>
2526 Whether requests to <application>Privoxy's</application> CGI pages can be blocked or redirected.
2531 <term>Type of value:</term>
2534 <replaceable>0 or 1</replaceable>
2539 <term>Default value:</term>
2541 <para><emphasis>0</emphasis></para>
2545 <term>Effect if unset:</term>
2548 <application>Privoxy</application> ignores block and redirect actions for its CGI pages.
2556 By default <application>Privoxy</application> ignores block or redirect actions
2557 for its CGI pages. Intercepting these requests can be useful in multi-user
2558 setups to implement fine-grained access control, but it can also render the complete
2559 web interface useless and make debugging problems painful if done without care.
2562 Don't enable this option unless you're sure that you really need it.
2567 <term>Examples:</term>
2570 allow-cgi-request-crunching 1
2575 <![%config-file;[<literallayout>@@allow-cgi-request-crunching 0</literallayout>]]>
2578 <sect3 renderas="sect4" id="split-large-forms"><title>split-large-forms</title>
2581 <term>Specifies:</term>
2584 Whether the CGI interface should stay compatible with broken HTTP clients.
2589 <term>Type of value:</term>
2592 <replaceable>0 or 1</replaceable>
2597 <term>Default value:</term>
2599 <para><emphasis>0</emphasis></para>
2603 <term>Effect if unset:</term>
2606 The CGI form generate long GET URLs.
2614 <application>Privoxy's</application> CGI forms can lead to
2615 rather long URLs. This isn't a problem as far as the HTTP
2616 standard is concerned, but it can confuse clients with arbitrary
2617 URL length limitations.
2620 Enabling split-large-forms causes <application>Privoxy</application>
2621 to divide big forms into smaller ones to keep the URL length down.
2622 It makes editing a lot less convenient and you can no longer
2623 submit all changes at once, but at least it works around this
2627 If you don't notice any editing problems, there is no reason
2628 to enable this option, but if one of the submit buttons appears
2629 to be broken, you should give it a try.
2634 <term>Examples:</term>
2642 <![%config-file;[<literallayout>@@split-large-forms 0</literallayout>]]>
2645 <sect3 renderas="sect4" id="keep-alive-timeout"><title>keep-alive-timeout</title>
2648 <term>Specifies:</term>
2651 Number of seconds after which an open connection will no longer be reused.
2656 <term>Type of value:</term>
2659 <replaceable>Time in seconds.</replaceable>
2664 <term>Default value:</term>
2670 <term>Effect if unset:</term>
2673 Connections are not kept alive.
2681 This option allows clients to keep the connection to &my-app;
2682 alive. If the server supports it, &my-app; will keep
2683 the connection to the server alive as well. Under certain
2684 circumstances this may result in speed-ups.
2687 By default, &my-app; will close the connection to the server if
2688 the client connection gets closed, or if the specified timeout
2689 has been reached without a new request coming in. This behaviour
2690 can be changed with the <ulink
2691 url="#CONNECTION-SHARING">connection-sharing</ulink> option.
2694 This option has no effect if <application>Privoxy</application>
2695 has been compiled without keep-alive support.
2698 Note that a timeout of five seconds as used in the default
2699 configuration file significantly decreases the number of
2700 connections that will be reused. The value is used because
2701 some browsers limit the number of connections they open to
2702 a single host and apply the same limit to proxies. This can
2703 result in a single website <quote>grabbing</quote> all the
2704 connections the browser allows, which means connections to
2705 other websites can't be opened until the connections currently
2709 Several users have reported this as a Privoxy bug, so the
2710 default value has been reduced. Consider increasing it to
2711 300 seconds or even more if you think your browser can handle
2712 it. If your browser appears to be hanging, it probably can't.
2717 <term>Examples:</term>
2720 keep-alive-timeout 300
2725 <![%config-file;[<literallayout>@@keep-alive-timeout 5</literallayout>]]>
2729 <sect3 renderas="sect4" id="tolerate-pipelining"><title>tolerate-pipelining</title>
2732 <term>Specifies:</term>
2735 Whether or not pipelined requests should be served.
2740 <term>Type of value:</term>
2743 <replaceable>0 or 1.</replaceable>
2748 <term>Default value:</term>
2754 <term>Effect if unset:</term>
2757 If Privoxy receives more than one request at once, it terminates the
2758 client connection after serving the first one.
2766 &my-app; currently doesn't pipeline outgoing requests,
2767 thus allowing pipelining on the client connection is not
2768 guaranteed to improve the performance.
2771 By default &my-app; tries to discourage clients from pipelining
2772 by discarding aggressively pipelined requests, which forces the
2773 client to resend them through a new connection.
2776 This option lets &my-app; tolerate pipelining. Whether or not
2777 that improves performance mainly depends on the client configuration.
2780 If you are seeing problems with pages not properly loading,
2781 disabling this option could work around the problem.
2786 <term>Examples:</term>
2789 tolerate-pipelining 1
2794 <![%config-file;[<literallayout>@@tolerate-pipelining 1</literallayout>]]>
2798 <sect3 renderas="sect4" id="default-server-timeout"><title>default-server-timeout</title>
2801 <term>Specifies:</term>
2804 Assumed server-side keep-alive timeout if not specified by the server.
2809 <term>Type of value:</term>
2812 <replaceable>Time in seconds.</replaceable>
2817 <term>Default value:</term>
2823 <term>Effect if unset:</term>
2826 Connections for which the server didn't specify the keep-alive
2827 timeout are not reused.
2835 Enabling this option significantly increases the number of connections
2836 that are reused, provided the <ulink
2837 url="#KEEP-ALIVE-TIMEOUT">keep-alive-timeout</ulink> option
2841 While it also increases the number of connections problems
2842 when &my-app; tries to reuse a connection that already has
2843 been closed on the server side, or is closed while &my-app;
2844 is trying to reuse it, this should only be a problem if it
2845 happens for the first request sent by the client. If it happens
2846 for requests on reused client connections, &my-app; will simply
2847 close the connection and the client is supposed to retry the
2848 request without bothering the user.
2851 Enabling this option is therefore only recommended if the
2853 url="#CONNECTION-SHARING">connection-sharing</ulink> option
2857 It is an error to specify a value larger than the <ulink
2858 url="#KEEP-ALIVE-TIMEOUT">keep-alive-timeout</ulink> value.
2861 This option has no effect if <application>Privoxy</application>
2862 has been compiled without keep-alive support.
2867 <term>Examples:</term>
2870 default-server-timeout 60
2875 <![%config-file;[<literallayout>@@#default-server-timeout 60</literallayout>]]>
2879 <sect3 renderas="sect4" id="connection-sharing"><title>connection-sharing</title>
2882 <term>Specifies:</term>
2885 Whether or not outgoing connections that have been kept alive
2886 should be shared between different incoming connections.
2891 <term>Type of value:</term>
2894 <replaceable>0 or 1</replaceable>
2899 <term>Default value:</term>
2905 <term>Effect if unset:</term>
2908 Connections are not shared.
2916 This option has no effect if <application>Privoxy</application>
2917 has been compiled without keep-alive support, or if it's disabled.
2925 Note that reusing connections doesn't necessary cause speedups.
2926 There are also a few privacy implications you should be aware of.
2929 If this option is effective, outgoing connections are shared between
2930 clients (if there are more than one) and closing the browser that initiated
2931 the outgoing connection does no longer affect the connection between &my-app;
2932 and the server unless the client's request hasn't been completed yet.
2935 If the outgoing connection is idle, it will not be closed until either
2936 <application>Privoxy's</application> or the server's timeout is reached.
2937 While it's open, the server knows that the system running &my-app; is still
2941 If there are more than one client (maybe even belonging to multiple users),
2942 they will be able to reuse each others connections. This is potentially
2943 dangerous in case of authentication schemes like NTLM where only the
2944 connection is authenticated, instead of requiring authentication for
2948 If there is only a single client, and if said client can keep connections
2949 alive on its own, enabling this option has next to no effect. If the client
2950 doesn't support connection keep-alive, enabling this option may make sense
2951 as it allows &my-app; to keep outgoing connections alive even if the client
2952 itself doesn't support it.
2955 You should also be aware that enabling this option increases the likelihood
2956 of getting the "No server or forwarder data" error message, especially if you
2957 are using a slow connection to the Internet.
2960 This option should only be used by experienced users who
2961 understand the risks and can weight them against the benefits.
2966 <term>Examples:</term>
2969 connection-sharing 1
2974 <![%config-file;[<literallayout>@@#connection-sharing 1</literallayout>]]>
2978 <sect3 renderas="sect4" id="socket-timeout"><title>socket-timeout</title>
2981 <term>Specifies:</term>
2984 Number of seconds after which a socket times out if
2985 no data is received.
2990 <term>Type of value:</term>
2993 <replaceable>Time in seconds.</replaceable>
2998 <term>Default value:</term>
3004 <term>Effect if unset:</term>
3007 A default value of 300 seconds is used.
3015 The default is quite high and you probably want to reduce it.
3016 If you aren't using an occasionally slow proxy like Tor, reducing
3017 it to a few seconds should be fine.
3022 <term>Examples:</term>
3030 <![%config-file;[<literallayout>@@socket-timeout 300</literallayout>]]>
3034 <sect3 renderas="sect4" id="max-client-connections"><title>max-client-connections</title>
3037 <term>Specifies:</term>
3040 Maximum number of client connections that will be served.
3045 <term>Type of value:</term>
3048 <replaceable>Positive number.</replaceable>
3053 <term>Default value:</term>
3059 <term>Effect if unset:</term>
3062 Connections are served until a resource limit is reached.
3070 &my-app; creates one thread (or process) for every incoming client
3071 connection that isn't rejected based on the access control settings.
3074 If the system is powerful enough, &my-app; can theoretically deal with
3075 several hundred (or thousand) connections at the same time, but some
3076 operating systems enforce resource limits by shutting down offending
3077 processes and their default limits may be below the ones &my-app; would
3078 require under heavy load.
3081 Configuring &my-app; to enforce a connection limit below the thread
3082 or process limit used by the operating system makes sure this doesn't
3083 happen. Simply increasing the operating system's limit would work too,
3084 but if &my-app; isn't the only application running on the system,
3085 you may actually want to limit the resources used by &my-app;.
3088 If &my-app; is only used by a single trusted user, limiting the
3089 number of client connections is probably unnecessary. If there
3090 are multiple possibly untrusted users you probably still want to
3091 additionally use a packet filter to limit the maximal number of
3092 incoming connections per client. Otherwise a malicious user could
3093 intentionally create a high number of connections to prevent other
3094 users from using &my-app;.
3097 Obviously using this option only makes sense if you choose a limit
3098 below the one enforced by the operating system.
3101 One most POSIX-compliant systems &my-app; can't properly deal with
3102 more than FD_SETSIZE file descriptors at the same time and has to reject
3103 connections if the limit is reached. This will likely change in a
3104 future version, but currently this limit can't be increased without
3105 recompiling &my-app; with a different FD_SETSIZE limit.
3110 <term>Examples:</term>
3113 max-client-connections 256
3118 <![%config-file;[<literallayout>@@#max-client-connections 256</literallayout>]]>
3122 <sect3 renderas="sect4" id="listen-backlog"><title>listen-backlog</title>
3125 <term>Specifies:</term>
3128 Connection queue length requested from the operating system.
3133 <term>Type of value:</term>
3136 <replaceable>Number.</replaceable>
3141 <term>Default value:</term>
3147 <term>Effect if unset:</term>
3150 A connection queue length of 128 is requested from the operating system.
3158 Under high load incoming connection may queue up before Privoxy
3159 gets around to serve them. The queue length is limitted by the
3160 operating system. Once the queue is full, additional connections
3161 are dropped before Privoxy can accept and serve them.
3164 Increasing the queue length allows Privoxy to accept more
3165 incomming connections that arrive roughly at the same time.
3168 Note that Privoxy can only request a certain queue length,
3169 whether or not the requested length is actually used depends
3170 on the operating system which may use a different length instead.
3173 On many operating systems a limit of -1 can be specified to
3174 instruct the operating system to use the maximum queue length
3175 allowed. Check the listen man page to see if your platform allows this.
3178 On some platforms you can use "netstat -Lan -p tcp" to see the effective
3182 Effectively using a value above 128 usually requires changing
3183 the system configuration as well. On FreeBSD-based system the
3184 limit is controlled by the kern.ipc.soacceptqueue sysctl.
3189 <term>Examples:</term>
3197 <![%config-file;[<literallayout>@@#listen-backlog -1</literallayout>]]>
3201 <sect3 renderas="sect4" id="enable-accept-filter"><title>enable-accept-filter</title>
3204 <term>Specifies:</term>
3207 Whether or not Privoxy should use an accept filter
3212 <term>Type of value:</term>
3215 <replaceable>0 or 1</replaceable>
3220 <term>Default value:</term>
3226 <term>Effect if unset:</term>
3229 No accept filter is enabled.
3237 Accept filters reduce the number of context switches by not
3238 passing sockets for new connections to Privoxy until a complete
3239 HTTP request is available.
3242 As a result, Privoxy can process the whole request right away
3243 without having to wait for additional data first.
3246 For this option to work, Privoxy has to be compiled with
3247 FEATURE_ACCEPT_FILTER and the operating system has to support
3248 it (which may require loading a kernel module).
3251 Currently accept filters are only supported on FreeBSD-based
3253 <ulink url="https://www.freebsd.org/cgi/man.cgi?query=accf_http">accf_http(9)
3255 to learn how to enable the support in the operating system.
3260 <term>Examples:</term>
3263 enable-accept-filter 1
3268 <![%config-file;[<literallayout>@@#enable-accept-filter 1</literallayout>]]>
3272 <sect3 renderas="sect4" id="handle-as-empty-doc-returns-ok"><title>handle-as-empty-doc-returns-ok</title>
3275 <term>Specifies:</term>
3278 The status code Privoxy returns for pages blocked with
3279 <!-- URL will only end up in the user manual so the relative link should work. -->
3280 <literal><ulink url="actions-file.html#HANDLE-AS-EMPTY-DOCUMENT">+handle-as-empty-document</ulink></literal>.
3285 <term>Type of value:</term>
3288 <replaceable>0 or 1</replaceable>
3293 <term>Default value:</term>
3299 <term>Effect if unset:</term>
3302 Privoxy returns a status 403(forbidden) for all blocked pages.
3307 <term>Effect if set:</term>
3310 Privoxy returns a status 200(OK) for pages blocked with +handle-as-empty-document
3311 and a status 403(Forbidden) for all other blocked pages.
3319 This directive was added as a work-around for Firefox bug 492459:
3320 <quote>Websites are no longer rendered if SSL requests for JavaScripts are blocked by a proxy.</quote>
3321 (<ulink url="https://bugzilla.mozilla.org/show_bug.cgi?id=492459"
3322 >https://bugzilla.mozilla.org/show_bug.cgi?id=492459</ulink>),
3323 the bug has been fixed for quite some time, but this directive is also useful
3324 to make it harder for websites to detect whether or not resources are being
3330 <![%config-file;[<literallayout>@@#handle-as-empty-doc-returns-ok 1</literallayout>]]>
3334 <sect3 renderas="sect4" id="enable-compression"><title>enable-compression</title>
3337 <term>Specifies:</term>
3340 Whether or not buffered content is compressed before delivery.
3345 <term>Type of value:</term>
3348 <replaceable>0 or 1</replaceable>
3353 <term>Default value:</term>
3359 <term>Effect if unset:</term>
3362 Privoxy does not compress buffered content.
3367 <term>Effect if set:</term>
3370 Privoxy compresses buffered content before delivering it to the client,
3371 provided the client supports it.
3379 This directive is only supported if Privoxy has been compiled with
3380 FEATURE_COMPRESSION, which should not to be confused with FEATURE_ZLIB.
3383 Compressing buffered content is mainly useful if Privoxy and the
3384 client are running on different systems. If they are running on the
3385 same system, enabling compression is likely to slow things down.
3386 If you didn't measure otherwise, you should assume that it does
3387 and keep this option disabled.
3390 Privoxy will not compress buffered content below a certain length.
3395 <![%config-file;[<literallayout>@@#enable-compression 1</literallayout>]]>
3399 <sect3 renderas="sect4" id="compression-level"><title>compression-level</title>
3402 <term>Specifies:</term>
3405 The compression level that is passed to the zlib library when compressing buffered content.
3410 <term>Type of value:</term>
3413 <replaceable>Positive number ranging from 0 to 9.</replaceable>
3418 <term>Default value:</term>
3427 Compressing the data more takes usually longer than compressing
3428 it less or not compressing it at all. Which level is best depends
3429 on the connection between Privoxy and the client. If you can't
3430 be bothered to benchmark it for yourself, you should stick with
3431 the default and keep compression disabled.
3434 If compression is disabled, the compression level is irrelevant.
3439 <term>Examples:</term>
3442 # Best speed (compared to the other levels)
3446 # No compression. Only useful for testing as the added header
3447 # slightly increases the amount of data that has to be sent.
3448 # If your benchmark shows that using this compression level
3449 # is superior to using no compression at all, the benchmark
3450 # is likely to be flawed.
3456 <![%config-file;[<literallayout>@@#compression-level 1</literallayout>]]>
3460 <sect3 renderas="sect4" id="client-header-order"><title>client-header-order</title>
3463 <term>Specifies:</term>
3466 The order in which client headers are sorted before forwarding them.
3471 <term>Type of value:</term>
3474 <replaceable>Client header names delimited by spaces or tabs</replaceable>
3479 <term>Default value:</term>
3488 By default &my-app; leaves the client headers in the order they
3489 were sent by the client. Headers are modified in-place, new headers
3490 are added at the end of the already existing headers.
3493 The header order can be used to fingerprint client requests
3494 independently of other headers like the User-Agent.
3497 This directive allows to sort the headers differently to better
3498 mimic a different User-Agent. Client headers will be emitted
3499 in the order given, headers whose name isn't explicitly specified
3500 are added at the end.
3503 Note that sorting headers in an uncommon way will make fingerprinting
3504 actually easier. Encrypted headers are not affected by this directive.
3509 <![%config-file;[<literallayout>@@#client-header-order Host \
3526 <sect3 renderas="sect4" id="client-specific-tag"><title>client-specific-tag</title>
3529 <term>Specifies:</term>
3532 The name of a tag that will always be set for clients that
3533 requested it through the webinterface.
3538 <term>Type of value:</term>
3541 <replaceable>Tag name followed by a description that will be shown in the webinterface</replaceable>
3546 <term>Default value:</term>
3556 This is an experimental feature. The syntax is likely to change
3561 Client-specific tags allow Privoxy admins to create different
3562 profiles and let the users chose which one they want without
3563 impacting other users.
3566 One use case is allowing users to circumvent certain blocks
3567 without having to allow them to circumvent all blocks.
3568 This is not possible with the
3569 <link linkend="enable-remote-toggle">enable-remote-toggle feature</link>
3570 because it would bluntly disable all blocks for all users and also affect
3571 other actions like filters.
3572 It also is set globally which renders it useless in most multi-user setups.
3575 After a client-specific tag has been defined with the client-specific-tag
3576 directive, action sections can be activated based on the tag by using a
3577 <ulink url="actions-file.html#CLIENT-TAG-PATTERN">CLIENT-TAG</ulink> pattern.
3578 The CLIENT-TAG pattern is evaluated at the same priority
3579 as URL patterns, as a result the last matching pattern wins.
3580 Tags that are created based on client or server headers are evaluated
3581 later on and can overrule CLIENT-TAG and URL patterns!
3584 The tag is set for all requests that come from clients that requested
3586 Note that "clients" are differentiated by IP address,
3587 if the IP address changes the tag has to be requested again.
3590 Clients can request tags to be set by using the CGI interface <ulink
3591 url="http://config.privoxy.org/client-tags">http://config.privoxy.org/client-tags</ulink>.
3592 The specific tag description is only used on the web page and should
3593 be phrased in away that the user understand the effect of the tag.
3598 <term>Examples:</term>
3601 # Define a couple of tags, the described effect requires action sections
3602 # that are enabled based on CLIENT-TAG patterns.
3603 client-specific-tag circumvent-blocks Overrule blocks but do not affect other actions
3604 disable-content-filters Disable content-filters but do not affect other actions
3611 <!-- ~ End section ~ -->
3613 <sect3 renderas="sect4" id="client-tag-lifetime"><title>client-tag-lifetime</title>
3616 <term>Specifies:</term>
3619 How long a temporarily enabled tag remains enabled.
3624 <term>Type of value:</term>
3627 <replaceable>Time in seconds.</replaceable>
3632 <term>Default value:</term>
3642 This is an experimental feature. The syntax is likely to change
3647 In case of some tags users may not want to enable them permanently,
3648 but only for a short amount of time, for example to circumvent a block
3649 that is the result of an overly-broad URL pattern.
3652 The CGI interface <ulink
3653 url="http://config.privoxy.org/client-tags">http://config.privoxy.org/client-tags</ulink>
3654 therefore provides a "enable this tag temporarily" option.
3655 If it is used, the tag will be set until the client-tag-lifetime
3661 <term>Examples:</term>
3664 # Increase the time to life for temporarily enabled tags to 3 minutes
3665 client-tag-lifetime 180
3672 <!-- ~ End section ~ -->
3674 <sect3 renderas="sect4" id="trust-x-forwarded-for"><title>trust-x-forwarded-for</title>
3677 <term>Specifies:</term>
3680 Whether or not Privoxy should use IP addresses specified with the X-Forwarded-For header
3685 <term>Type of value:</term>
3688 <replaceable>0 or one</replaceable>
3693 <term>Default value:</term>
3703 This is an experimental feature. The syntax is likely to change
3708 If clients reach Privoxy through another proxy, for example a load
3709 balancer, Privoxy can't tell the client's IP address from the connection.
3710 If multiple clients use the same proxy, they will share the same
3711 client tag settings which is usually not desired.
3714 This option lets Privoxy use the X-Forwarded-For header value as
3715 client IP address. If the proxy sets the header, multiple clients
3716 using the same proxy do not share the same client tag settings.
3719 This option should only be enabled if Privoxy can only be reached
3720 through a proxy and if the proxy can be trusted to set the header
3721 correctly. It is recommended that ACL are used to make sure only
3722 trusted systems can reach Privoxy.
3725 If access to Privoxy isn't limited to trusted systems, this option
3726 would allow malicious clients to change the client tags for other
3727 clients or increase Privoxy's memory requirements by registering
3728 lots of client tag settings for clients that don't exist.
3733 <term>Examples:</term>
3736 # Allow systems that can reach Privoxy to provide the client
3737 # IP address with a X-Forwarded-For header.
3738 trust-x-forwarded-for 1
3745 <!-- ~ End section ~ -->
3747 <!-- ~~~~~ New section ~~~~~ -->
3749 <sect3 renderas="sect4" id="receive-buffer-size"><title>receive-buffer-size</title>
3752 <term>Specifies:</term>
3755 The size of the buffer Privoxy uses to receive data from the server.
3760 <term>Type of value:</term>
3763 <replaceable>Size in bytes</replaceable>
3768 <term>Default value:</term>
3777 Increasing the receive-buffer-size increases Privoxy's memory usage but
3778 can lower the number of context switches and thereby reduce the
3779 cpu usage and potentially increase the throughput.
3782 This is mostly relevant for fast network connections and
3783 large downloads that don't require filtering.
3786 Reducing the buffer size reduces the amount of memory Privoxy
3787 needs to handle the request but increases the number of systemcalls
3788 and may reduce the throughput.
3791 A dtrace command like:
3792 <quote>sudo dtrace -n 'syscall::read:return /execname == "privoxy"/ { @[execname] = llquantize(arg0, 10, 0, 5, 20); @m = max(arg0)}'</quote>
3793 can be used to properly tune the receive-buffer-size.
3794 On systems without dtrace, strace or truss may be used as
3795 less convenient alternatives.
3798 If the buffer is too large it will increase Privoxy's memory
3799 footprint without any benefit. As the memory is (currently)
3800 cleared before using it, a buffer that is too large can
3801 actually reduce the throughput.
3806 <term>Examples:</term>
3809 # Increase the receive buffer size
3810 receive-buffer-size 32768
3817 <!-- ~ End section ~ -->
3821 <!-- ~~~~~ New section ~~~~~ -->
3823 <sect2 id="windows-gui">
3824 <title>Windows GUI Options</title>
3826 <application>Privoxy</application> has a number of options specific to the
3827 Windows GUI interface:
3830 <anchor id="activity-animation">
3831 <![%config-file;[<para>@@</para>]]> <!-- for spacing -->
3833 If <quote>activity-animation</quote> is set to 1, the
3834 <application>Privoxy</application> icon will animate when
3835 <quote>Privoxy</quote> is active. To turn off, set to 0.
3838 <![%config-file;[<literallayout>@@#activity-animation 1</literallayout>]]>
3844 <emphasis>activity-animation 1</emphasis>
3851 <anchor id="log-messages">
3852 <![%config-file;[<para>@@</para>]]> <!-- for spacing -->
3854 If <quote>log-messages</quote> is set to 1,
3855 <application>Privoxy</application> copies log messages to the console
3857 The log detail depends on the <link linkend="debug">debug</link> directive.
3860 <![%config-file;[<literallayout>@@#log-messages 1</literallayout>]]>
3866 <emphasis>log-messages 1</emphasis>
3873 <anchor id="log-buffer-size">
3874 <![%config-file;[<para>@@</para>]]> <!-- for spacing -->
3876 If <quote>log-buffer-size</quote> is set to 1, the size of the log buffer,
3877 i.e. the amount of memory used for the log messages displayed in the
3878 console window, will be limited to <quote>log-max-lines</quote> (see below).
3882 Warning: Setting this to 0 will result in the buffer to grow infinitely and
3883 eat up all your memory!
3886 <![%config-file;[<literallayout>@@#log-buffer-size 1</literallayout>]]>
3892 <emphasis>log-buffer-size 1</emphasis>
3899 <anchor id="log-max-lines">
3900 <![%config-file;[<para>@@</para>]]> <!-- for spacing -->
3902 <application>log-max-lines</application> is the maximum number of lines held
3903 in the log buffer. See above.
3906 <![%config-file;[<literallayout>@@#log-max-lines 200</literallayout>]]>
3912 <emphasis>log-max-lines 200</emphasis>
3919 <anchor id="log-highlight-messages">
3920 <![%config-file;[<para>@@</para>]]> <!-- for spacing -->
3922 If <quote>log-highlight-messages</quote> is set to 1,
3923 <application>Privoxy</application> will highlight portions of the log
3924 messages with a bold-faced font:
3927 <![%config-file;[<literallayout>@@#log-highlight-messages 1</literallayout>]]>
3933 <emphasis>log-highlight-messages 1</emphasis>
3940 <anchor id="log-font-name">
3941 <![%config-file;[<para>@@</para>]]> <!-- for spacing -->
3943 The font used in the console window:
3946 <![%config-file;[<literallayout>@@#log-font-name Comic Sans MS</literallayout>]]>
3952 <emphasis>log-font-name Comic Sans MS</emphasis>
3959 <anchor id="log-font-size">
3960 <![%config-file;[<para>@@</para>]]> <!-- for spacing -->
3962 Font size used in the console window:
3965 <![%config-file;[<literallayout>@@#log-font-size 8</literallayout>]]>
3971 <emphasis>log-font-size 8</emphasis>
3978 <anchor id="show-on-task-bar">
3979 <![%config-file;[<para>@@</para>]]> <!-- for spacing -->
3981 <quote>show-on-task-bar</quote> controls whether or not
3982 <application>Privoxy</application> will appear as a button on the Task bar
3986 <![%config-file;[<literallayout>@@#show-on-task-bar 0</literallayout>]]>
3992 <emphasis>show-on-task-bar 0</emphasis>
3999 <anchor id="close-button-minimizes">
4000 <![%config-file;[<para>@@</para>]]> <!-- for spacing -->
4002 If <quote>close-button-minimizes</quote> is set to 1, the Windows close
4003 button will minimize <application>Privoxy</application> instead of closing
4004 the program (close with the exit option on the File menu).
4007 <![%config-file;[<literallayout>@@#close-button-minimizes 1</literallayout>]]>
4013 <emphasis>close-button-minimizes 1</emphasis>
4020 <anchor id="hide-console">
4021 <![%config-file;[<para>@@</para>]]> <!-- for spacing -->
4023 The <quote>hide-console</quote> option is specific to the MS-Win console
4024 version of <application>Privoxy</application>. If this option is used,
4025 <application>Privoxy</application> will disconnect from and hide the
4029 <![%config-file;[<literallayout>@@#hide-console</literallayout>]]>
4035 #<emphasis>hide-console</emphasis>
4045 <!-- end config content common to both outputs -->
4048 <!-- These are dummy anchors to keep the processor quiet -->
4049 <!-- when building config-file only (ie. they are used in u-m only) -->
4052 <anchor id="filter">
4053 <anchor id="filter-file">
4055 <anchor id="actions-file">
4056 <anchor id="af-patterns">
4060 <!-- eof p-config.sgml -->