1 <!DOCTYPE article PUBLIC "-//OASIS//DTD DocBook V3.1//EN" [
2 <!entity % dummy "IGNORE">
3 <!entity supported SYSTEM "supported.sgml">
4 <!entity newfeatures SYSTEM "newfeatures.sgml">
5 <!entity p-intro SYSTEM "privoxy.sgml">
6 <!entity seealso SYSTEM "seealso.sgml">
7 <!entity buildsource SYSTEM "buildsource.sgml">
8 <!entity contacting SYSTEM "contacting.sgml">
9 <!entity history SYSTEM "history.sgml">
10 <!entity copyright SYSTEM "copyright.sgml">
11 <!entity license SYSTEM "license.sgml">
12 <!entity p-authors SYSTEM "p-authors.sgml">
13 <!entity config SYSTEM "p-config.sgml">
14 <!entity p-version "3.0.9">
15 <!entity p-status "UNRELEASED">
16 <!entity % p-authors-formal "INCLUDE"> <!-- include additional text, etc -->
17 <!entity % p-not-stable "INCLUDE">
18 <!entity % p-stable "IGNORE">
19 <!entity % p-text "IGNORE"> <!-- define we are not a text only doc -->
20 <!entity % p-doc "INCLUDE"> <!-- and we are a formal doc -->
21 <!entity % p-readme "IGNORE">
22 <!entity % user-man "IGNORE">
23 <!entity % config-file "IGNORE">
24 <!entity % p-supp-userman "IGNORE"> <!-- Omit some from supported.sgml -->
25 <!entity my-copy "©"> <!-- kludge for docbook2man -->
26 <!entity % draft "IGNORE"> <!-- WIP stuff -->
27 <!entity my-app "<application>Privoxy</application>">
30 File : $Source: /cvsroot/ijbswa/current/doc/source/user-manual.sgml,v $
33 This file belongs into
34 ijbswa.sourceforge.net:/home/groups/i/ij/ijbswa/htdocs/
36 $Id: user-manual.sgml,v 2.65 2008/03/04 18:30:40 fabiankeil Exp $
38 Copyright (C) 2001-2008 Privoxy Developers http://www.privoxy.org/
41 ========================================================================
42 NOTE: Please read developer-manual/documentation.html before touching
43 anything in this, or other Privoxy documentation.
44 ========================================================================
51 <title>Privoxy &p-version; User Manual</title>
55 <!-- Completely the wrong markup, but very little is allowed -->
56 <!-- in this part of an article. FIXME -->
57 <link linkend="copyright">Copyright</link> &my-copy; 2001 - 2008 by
58 <ulink url="http://www.privoxy.org/">Privoxy Developers</ulink>
62 <pubdate>$Id: user-manual.sgml,v 2.65 2008/03/04 18:30:40 fabiankeil Exp $</pubdate>
66 Note: the following should generate a separate page, and a live link to it,
67 all nicely done. But it doesn't for some mysterious reason. Please leave
68 commented unless it can be fixed proper. For the time being, the
69 copyright/license declarations will be in their own sgml.
82 This is here to keep vim syntax file from breaking :/
83 If I knew enough to fix it, I would.
84 PLEASE DO NOT REMOVE! HB: hal@foobox.net
90 The <citetitle>Privoxy User Manual</citetitle> gives users information on how to
91 install, configure and use <ulink
92 url="http://www.privoxy.org/">Privoxy</ulink>.
95 <!-- Include privoxy.sgml boilerplate: -->
97 <!-- end privoxy.sgml -->
100 You can find the latest version of the <citetitle>Privoxy User Manual</citetitle> at <ulink
101 url="http://www.privoxy.org/user-manual/">http://www.privoxy.org/user-manual/</ulink>.
102 Please see the <link linkend="contact">Contact section</link> on how to
103 contact the developers.
107 <!-- Feel free to send a note to the developers at <email>ijbswa-developers@lists.sourceforge.net</email>. -->
113 <!-- ~~~~~ New section ~~~~~ -->
114 <sect1 label="1" id="introduction"><title>Introduction</title>
116 This documentation is included with the current &p-status; version of
117 <application>Privoxy</application>, v.&p-version;<![%p-not-stable;[,
118 and is mostly complete at this point. The most up to date reference for the
119 time being is still the comments in the source files and in the individual
120 configuration files. Development of a new version is currently nearing
121 completion, and includes significant changes and enhancements over
122 earlier versions. ]]>.
125 <!-- include only in non-stable versions -->
128 Since this is a &p-status; version, not all new features are well tested. This
129 documentation may be slightly out of sync as a result (especially with
130 CVS sources). And there <emphasis>may be</emphasis> bugs, though hopefully
135 <!-- ~~~~~ New section ~~~~~ -->
136 <sect2 id="features"><title>Features</title>
138 In addition to the core
139 features of ad blocking and
140 <ulink url="http://en.wikipedia.org/wiki/Browser_cookie">cookie</ulink> management,
141 <application>Privoxy</application> provides many supplemental
142 features<![%p-not-stable;[, some of them currently under development]]>,
143 that give the end-user more control, more privacy and more freedom:
145 <!-- Include newfeatures.sgml boilerplate here: -->
147 <!-- end boilerplate -->
152 <!-- ~ End section ~ -->
155 <!-- ~~~~~ New section ~~~~~ -->
156 <sect1 id="installation"><title>Installation</title>
159 <application>Privoxy</application> is available both in convenient pre-compiled
160 packages for a wide range of operating systems, and as raw source code.
161 For most users, we recommend using the packages, which can be downloaded from our
162 <ulink url="http://sourceforge.net/projects/ijbswa/">Privoxy Project
168 On some platforms, the installer may remove previously installed versions, if
169 found. (See below for your platform). In any case <emphasis>be sure to backup
170 your old configuration if it is valuable to you.</emphasis> See the <link
171 linkend="upgradersnote">note to upgraders</link> section below.
174 <!-- ~~~~~ New section ~~~~~ -->
175 <sect2 id="installation-packages"><title>Binary Packages</title>
177 How to install the binary packages depends on your operating system:
180 <!-- XXX: The installation sections should be sorted -->
182 <!-- ~~~~~ New section ~~~~~ -->
183 <sect3 id="installation-pack-rpm"><title>Red Hat and Fedora RPMs</title>
186 RPMs can be installed with <literal>rpm -Uvh privoxy-&p-version;-1.rpm</literal>,
187 and will use <filename>/etc/privoxy</filename> for the location
188 of configuration files.
192 Note that on Red Hat, <application>Privoxy</application> will
193 <emphasis>not</emphasis> be automatically started on system boot. You will
194 need to enable that using <command>chkconfig</command>,
195 <command>ntsysv</command>, or similar methods.
199 If you have problems with failed dependencies, try rebuilding the SRC RPM:
200 <literal>rpm --rebuild privoxy-&p-version;-1.src.rpm</literal>. This
201 will use your locally installed libraries and RPM version.
205 Also note that if you have a <application>Junkbuster</application> RPM installed
206 on your system, you need to remove it first, because the packages conflict.
207 Otherwise, RPM will try to remove <application>Junkbuster</application>
208 automatically if found, before installing <application>Privoxy</application>.
212 <!-- ~~~~~ New section ~~~~~ -->
213 <sect3 id="installation-deb"><title>Debian and Ubuntu</title>
215 DEBs can be installed with <literal>apt-get install privoxy</literal>,
216 and will use <filename>/etc/privoxy</filename> for the location of
221 <!-- ~~~~~ New section ~~~~~ -->
222 <sect3 id="installation-pack-win"><title>Windows</title>
225 Just double-click the installer, which will guide you through
226 the installation process. You will find the configuration files
227 in the same directory as you installed <application>Privoxy</application> in.
230 Version 3.0.5 beta introduced full <application>Windows</application> service
231 functionality. On Windows only, the <application>Privoxy</application>
232 program has two new command line arguments to install and uninstall
233 <application>Privoxy</application> as a <emphasis>service</emphasis>.
237 <term>Arguments:</term>
240 <replaceable class="parameter">--install</replaceable>[:<replaceable class="parameter">service_name</replaceable>]
243 <replaceable class="parameter">--uninstall</replaceable>[:<replaceable class="parameter">service_name</replaceable>]
249 After invoking <application>Privoxy</application> with
250 <command>--install</command>, you will need to bring up the
251 <application>Windows</application> service console to assign the user you
252 want <application>Privoxy</application> to run under, and whether or not you
253 want it to run whenever the system starts. You can start the
254 <application>Windows</application> services console with the following
255 command: <command>services.msc</command>. If you do not take the manual step
256 of modifying <application>Privoxy's</application> service settings, it will
257 not start. Note too that you will need to give Privoxy a user account that
258 actually exists, or it will not be permitted to
259 write to its log and configuration files.
264 <!-- ~~~~~ New section ~~~~~ -->
265 <sect3 id="installation-pack-bintgz"><title>Solaris <!--, NetBSD, HP-UX--></title>
268 Create a new directory, <literal>cd</literal> to it, then unzip and
269 untar the archive. For the most part, you'll have to figure out where
270 things go. <!-- FIXME, more info needed? -->
274 <!-- ~~~~~ New section ~~~~~ -->
275 <sect3 id="installation-os2"><title>OS/2</title>
278 First, make sure that no previous installations of
279 <application>Junkbuster</application> and / or
280 <application>Privoxy</application> are left on your
281 system. Check that no <application>Junkbuster</application>
282 or <application>Privoxy</application> objects are in
288 Then, just double-click the WarpIN self-installing archive, which will
289 guide you through the installation process. A shadow of the
290 <application>Privoxy</application> executable will be placed in your
291 startup folder so it will start automatically whenever OS/2 starts.
295 The directory you choose to install <application>Privoxy</application>
296 into will contain all of the configuration files.
300 <!-- ~~~~~ New section ~~~~~ -->
301 <sect3 id="installation-mac"><title>Mac OS X</title>
303 Unzip the downloaded file (you can either double-click on the zip file
304 icon from the Finder, or from the desktop if you downloaded it there).
305 Then, double-click on the package installer icon and follow the
306 installation process.
309 The privoxy service will automatically start after a successful
310 installation (in addition to every time your computer starts up). To
311 prevent the privoxy service from automatically starting when your
312 computer starts up, remove or rename the folder named
313 <literal>/Library/StartupItems/Privoxy</literal>.
316 To manually start or stop the privoxy service, use the Privoxy Utility
317 for Mac OS X. This application controls the privoxy service (e.g.
318 starting and stopping the service as well as uninstalling the software).
322 <!-- ~~~~~ New section ~~~~~ -->
323 <sect3 id="installation-amiga"><title>AmigaOS</title>
325 Copy and then unpack the <filename>lha</filename> archive to a suitable location.
326 All necessary files will be installed into <application>Privoxy</application>
327 directory, including all configuration and log files. To uninstall, just
328 remove this directory.
332 <!-- ~~~~~ New section ~~~~~ -->
333 <sect3 id="installation-tbz"><title>FreeBSD</title>
336 Privoxy is part of FreeBSD's Ports Collection, you can build and install
337 it with <literal>cd /usr/ports/www/privoxy; make install clean</literal>.
340 If you don't use the ports, you can fetch and install
341 the package with <literal>pkg_add -r privoxy</literal>.
344 The port skeleton and the package can also be downloaded from the
345 <ulink url="https://sourceforge.net/project/showfiles.php?group_id=11118">File Release
346 Page</ulink>, but there's no reason to use them unless you're interested in the
347 beta releases which are only available there.
351 <!-- ~~~~~ New section ~~~~~ -->
352 <sect3 id="installattion-gentoo"><title>Gentoo</title>
354 Gentoo source packages (Ebuilds) for <application>Privoxy</application> are
355 contained in the Gentoo Portage Tree (they are not on the download page,
356 but there is a Gentoo section, where you can see when a new
357 <application>Privoxy</application> Version is added to the Portage Tree).
360 Before installing <application>Privoxy</application> under Gentoo just do
361 first <literal>emerge rsync</literal> to get the latest changes from the
362 Portage tree. With <literal>emerge privoxy</literal> you install the latest
366 Configuration files are in <filename>/etc/privoxy</filename>, the
367 documentation is in <filename>/usr/share/doc/privoxy-&p-version;</filename>
368 and the Log directory is in <filename>/var/log/privoxy</filename>.
374 <!-- ~~~~~ New section ~~~~~ -->
375 <sect2 id="installation-source"><title>Building from Source</title>
378 The most convenient way to obtain the <application>Privoxy</application> sources
379 is to download the source tarball from our
380 <ulink url="http://sourceforge.net/project/showfiles.php?group_id=11118&package_id=10571">project download
385 If you like to live on the bleeding edge and are not afraid of using
386 possibly unstable development versions, you can check out the up-to-the-minute
387 version directly from <ulink url="http://sourceforge.net/cvs/?group_id=11118">the
388 CVS repository</ulink>.
390 deprecated...out of business.
391 or simply download <ulink
392 url="http://cvs.sourceforge.net/cvstarballs/ijbswa-cvsroot.tar.bz2">the nightly CVS
397 <!-- include buildsource.sgml boilerplate: -->
399 <!-- end boilerplate -->
402 <!-- ~~~~~ New section ~~~~~ -->
403 <sect2 id="installation-keepupdated"><title>Keeping your Installation Up-to-Date</title>
405 As user feedback comes in and development continues, we will make updated versions
406 of both the main <link linkend="actions-file">actions file</link> (as a <ulink
407 url="http://sourceforge.net/project/showfiles.php?group_id=11118&release_id=103670">separate
408 package</ulink>) and the software itself (including the actions file) available for
413 If you wish to receive an email notification whenever we release updates of
414 <application>Privoxy</application> or the actions file, <ulink
415 url="http://lists.sourceforge.net/lists/listinfo/ijbswa-announce/">subscribe
416 to our announce mailing list</ulink>, ijbswa-announce@lists.sourceforge.net.
420 In order not to lose your personal changes and adjustments when updating
421 to the latest <literal>default.action</literal> file we <emphasis>strongly
422 recommend</emphasis> that you use <literal>user.action</literal> and
423 <literal>user.filter</literal> for your local
424 customizations of <application>Privoxy</application>. See the <link
425 linkend="actions-file">Chapter on actions files</link> for details.
433 <!-- ~ End section ~ -->
435 <!-- ~~~~~ New section ~~~~~ -->
436 <sect1 id="whatsnew">
437 <title>What's New in this Release</title>
439 There are many improvements and new features since <application>Privoxy 3.0.6</application>, the last stable release:
446 Two new actions <link
447 linkend="server-header-tagger">server-header-tagger</link>
449 linkend="client-header-tagger">client-header-tagger</link>
450 that can be used to create arbitrary <quote>tags</quote>
451 based on client and server headers.
452 These <quote>tags</quote> can then subsequently be used
453 to control the other actions used for the current request,
454 greatly increasing &my-app;'s flexibility and selectivity. See <link
455 linkend="tag-pattern">tag patterns</link> for more information on tags.
461 Header filtering is done with dedicated header filters now. As a result
462 the actions <quote>filter-client-headers</quote> and <quote>filter-server-headers</quote>
463 that were introduced with <application>Privoxy 3.0.5</application> to apply
464 content filters to the headers have been removed.
465 See the new actions <link
466 linkend="server-header-filter">server-header-filter</link>
468 linkend="client-header-filter">client-header-filter</link> for details.
473 There are four new options for the main <filename>config</filename> file:
480 linkend="allow-cgi-request-crunching">allow-cgi-request-crunching</link>
481 which allows requests for Privoxy's internal CGI pages to be
482 blocked, redirected or (un)trusted like ordinary requests.
488 linkend="split-large-forms">split-large-forms</link>
489 that will work around a browser bug that caused IE6 and IE7 to
490 ignore the Submit button on the Privoxy's edit-actions-for-url CGI
497 linkend="accept-intercepted-requests">accept-intercepted-requests</link>
498 which allows to combine Privoxy with any packet filter to create an
499 intercepting proxy for HTTP/1.1 requests (and for HTTP/1.0 requests
500 with Host header set). This means clients can be forced to use
501 &my-app; even if their proxy settings are configured differently.
507 linkend="templdir">templdir</link>
508 to designate an alternate location for &my-app;'s
509 locally customized CGI templates so that
510 these are not overwritten during upgrades.
518 A new command line option <literal>--pre-chroot-nslookup hostname</literal> to
519 initialize the resolver library before chroot'ing. On some systems this
520 reduces the number of files that must be copied into the chroot tree.
521 (Patch provided by Stephen Gildea)
528 linkend="forward-override">forward-override</link> action
529 allows changing of the forwarding settings through the actions files.
530 Combined with tags, this allows to choose the forwarder based on
531 client headers like the <literal>User-Agent</literal>, or the request origin.
538 linkend="redirect">redirect</link> action can now use regular
539 expression substitutions against the original URL.
545 <application>zlib</application> support is now available as a compile
546 time option to filter compressed content. Patch provided by Wil Mahan.
551 Improve various filters, and add new ones.
558 Include support for RFC 3253 so that <filename>Subversion</filename> works
559 with &my-app;. Patch provided by Petr Kadlec.
565 Logging can be completely turned off by not specifying a logfile directive.
572 A number of improvements to Privoxy's internal CGI pages, including the
573 use of favicons for error and control pages.
579 Many bugfixes, memory leaks addressed, code improvements, and logging
587 For a more detailed list of changes please have a look at the ChangeLog.
590 <!-- ~~~~~ New section ~~~~~ -->
592 <sect2 id="upgradersnote">
593 <title>Note to Upgraders</title>
596 A quick list of things to be aware of before upgrading from earlier
597 versions of <application>Privoxy</application>:
605 The recommended way to upgrade &my-app; is to backup your old
606 configuration files, install the new ones, verify that &my-app;
607 is working correctly and finally merge back your changes using
608 <application>diff</application> and maybe <application>patch</application>.
611 There are a number of new features in each &my-app; release and
612 most of them have to be explicitly enabled in the configuration
613 files. Old configuration files obviously don't do that and due
614 to syntax changes using old configuration files with a new
615 &my-app; isn't always possible anyway.
620 Note that some installers remove earlier versions completely,
621 including configuration files, therefore you should really save
622 any important configuration files!
627 On the other hand, other installers don't overwrite existing configuration
628 files, thinking you will want to do that yourself.
633 <filename>standard.action</filename> now only includes the enabled actions.
634 Not all actions as before.
639 In the default configuration only fatal errors are logged now.
640 You can change that in the <link linkend="DEBUG">debug section</link>
641 of the configuration file. You may also want to enable more verbose
642 logging until you verified that the new &my-app; version is working
649 Three other config file settings are now off by default:
650 <link linkend="enable-remote-toggle">enable-remote-toggle</link>,
651 <link linkend="enable-remote-http-toggle">enable-remote-http-toggle</link>,
652 and <link linkend="enable-edit-actions">enable-edit-actions</link>.
653 If you use or want these, you will need to explicitly enable them, and
654 be aware of the security issues involved.
660 The <quote>filter-client-headers</quote> and
661 <quote>filter-server-headers</quote> actions that were introduced with
662 <application>Privoxy 3.0.5</application> to apply content filters to
663 the headers have been removed and replaced with new actions.
665 linkend="whatsnew">What's New section</link> above.
673 What constitutes a <quote>default</quote> configuration has changed,
674 and you may want to review which actions are <quote>on</quote> by
675 default. This is primarily a matter of emphasis, but some features
676 you may have been used to, may now be <quote>off</quote> by default.
677 There are also a number of new actions and filters you may want to
678 consider, most of which are not fully incorporated into the default
679 settings as yet (see above).
686 The default actions setting is now <literal>Cautious</literal>. Previous
687 releases had a default setting of <literal>Medium</literal>. Experienced
688 users may want to adjust this, as it is fairly conservative by &my-app;
689 standards and past practices. See <ulink
690 url="http://config.privoxy.org/edit-actions-list?f=default">
691 http://config.privoxy.org/edit-actions-list?f=default</ulink>. New users
692 should try the default settings for a while before turning up the volume.
698 The default setting has filtering turned <emphasis>off</emphasis>, which
699 subsequently means that compression is <emphasis>on</emphasis>. Remember
700 that filtering does not work on compressed pages, so if you use, or want to
701 use, filtering, you will need to force compression off. Example:
705 { +<link linkend="filter">filter</link>{google} +<link linkend="prevent-compression">prevent-compression</link> }
709 Or if you use a number of filters, or filter many sites, you may just want
710 to turn off compression for all sites in
711 <filename>default.action</filename> (or
712 <filename>user.action</filename>).
719 Also, <link linkend="SESSION-COOKIES-ONLY">session-cookies-only</link> is
720 off by default now. If you've liked this feature in the past, you may want
721 to turn it back on in <filename>user.action</filename> now.
728 Some installers may not automatically start
729 <application>Privoxy</application> after installation.
740 <!-- ~~~~~ New section ~~~~~ -->
741 <sect1 id="quickstart"><title>Quickstart to Using Privoxy</title>
747 Install <application>Privoxy</application>. See the <link
748 linkend="installation">Installation Section</link> below for platform specific
755 Advanced users and those who want to offer <application>Privoxy</application>
756 service to more than just their local machine should check the <link
757 linkend="config">main config file</link>, especially the <link
758 linkend="access-control">security-relevant</link> options. These are
765 Start <application>Privoxy</application>, if the installation program has
766 not done this already (may vary according to platform). See the section
767 <link linkend="startup">Starting <application>Privoxy</application></link>.
773 Set your browser to use <application>Privoxy</application> as HTTP and
774 HTTPS (SSL) <ulink url="http://en.wikipedia.org/wiki/Proxy_server">proxy</ulink>
775 by setting the proxy configuration for address of
776 <literal>127.0.0.1</literal> and port <literal>8118</literal>.
777 <emphasis>DO NOT</emphasis> activate proxying for <literal>FTP</literal> or
778 any protocols besides HTTP and HTTPS (SSL) unless you intend to prevent your
779 browser from using these protocols.
785 Flush your browser's disk and memory caches, to remove any cached ad images.
786 If using <application>Privoxy</application> to manage
787 <ulink url="http://en.wikipedia.org/wiki/Browser_cookie">cookies</ulink>,
788 you should remove any currently stored cookies too.
794 A default installation should provide a reasonable starting point for
795 most. There will undoubtedly be occasions where you will want to adjust the
796 configuration, but that can be dealt with as the need arises. Little
797 to no initial configuration is required in most cases, you may want
799 <ulink url="config.html#ENABLE-EDIT-ACTIONS">web-based action editor</ulink> though.
800 Be sure to read the warnings first.
803 See the <link linkend="configuration">Configuration section</link> for more
804 configuration options, and how to customize your installation.
805 You might also want to look at the <link
806 linkend="quickstart-ad-blocking">next section</link> for a quick
807 introduction to how <application>Privoxy</application> blocks ads and
814 If you experience ads that slip through, innocent images that are
815 blocked, or otherwise feel the need to fine-tune
816 <application>Privoxy's</application> behavior, take a look at the <link
817 linkend="actions-file">actions files</link>. As a quick start, you might
818 find the <link linkend="act-examples">richly commented examples</link>
819 helpful. You can also view and edit the actions files through the <ulink
820 url="http://config.privoxy.org">web-based user interface</ulink>. The
821 Appendix <quote><link linkend="actionsanat">Troubleshooting: Anatomy of an
822 Action</link></quote> has hints on how to understand and debug actions that
823 <quote>misbehave</quote>.
828 Did anyone test these lately?
832 For easy access to &my-app;'s most important controls, drag the provided
833 <link linkend="bookmarklets">Bookmarklets</link> into your browser's
841 Please see the section <link linkend="contact">Contacting the
842 Developers</link> on how to report bugs, problems with websites or to get
849 Now enjoy surfing with enhanced control, comfort and privacy!
857 <!-- ~~~~~ New section ~~~~~ -->
859 <sect2 id="quickstart-ad-blocking">
860 <title>Quickstart to Ad Blocking</title>
862 NOTE: This section is deliberately redundant for those that don't
863 want to read the whole thing (which is getting lengthy).
866 Ad blocking is but one of <application>Privoxy's</application>
867 array of features. Many of these features are for the technically minded advanced
868 user. But, ad and banner blocking is surely common ground for everybody.
871 This section will provide a quick summary of ad blocking so
872 you can get up to speed quickly without having to read the more extensive
873 information provided below, though this is highly recommended.
876 First a bit of a warning ... blocking ads is much like blocking SPAM: the
877 more aggressive you are about it, the more likely you are to block
878 things that were not intended. And the more likely that some things
879 may not work as intended. So there is a trade off here. If you want
880 extreme ad free browsing, be prepared to deal with more
881 <quote>problem</quote> sites, and to spend more time adjusting the
882 configuration to solve these unintended consequences. In short, there is
883 not an easy way to eliminate <emphasis>all</emphasis> ads. Either take
884 the easy way and settle for <emphasis>most</emphasis> ads blocked with the
885 default configuration, or jump in and tweak it for your personal surfing
886 habits and preferences.
889 Secondly, a brief explanation of <application>Privoxy's </application>
890 <quote>actions</quote>. <quote>Actions</quote> in this context, are
891 the directives we use to tell <application>Privoxy</application> to perform
892 some task relating to HTTP transactions (i.e. web browsing). We tell
893 <application>Privoxy</application> to take some <quote>action</quote>. Each
894 action has a unique name and function. While there are many potential
895 <application>actions</application> in <application>Privoxy's</application>
896 arsenal, only a few are used for ad blocking. <link
897 linkend="actions">Actions</link>, and <link linkend="actions-file">action
898 configuration files</link>, are explained in depth below.
901 Actions are specified in <application>Privoxy's</application> configuration,
902 followed by one or more URLs to which the action should apply. URLs
903 can actually be URL type <link linkend="af-patterns">patterns</link> that use
904 wildcards so they can apply potentially to a range of similar URLs. The
905 actions, together with the URL patterns are called a section.
908 When you connect to a website, the full URL will either match one or more
909 of the sections as defined in <application>Privoxy's</application> configuration,
910 or not. If so, then <application>Privoxy</application> will perform the
911 respective actions. If not, then nothing special happens. Furthermore, web
912 pages may contain embedded, secondary URLs that your web browser will
913 use to load additional components of the page, as it parses the
914 original page's HTML content. An ad image for instance, is just an URL
915 embedded in the page somewhere. The image itself may be on the same server,
916 or a server somewhere else on the Internet. Complex web pages will have many
917 such embedded URLs. &my-app; can deal with each URL individually, so, for
918 instance, the main page text is not touched, but images from such-and-such
923 The most important actions for basic ad blocking are: <literal><link
924 linkend="block">block</link></literal>, <literal><link
925 linkend="handle-as-image">handle-as-image</link></literal>,
927 linkend="handle-as-empty-document">handle-as-empty-document</link></literal>,and
928 <literal><link linkend="set-image-blocker">set-image-blocker</link></literal>:
936 <literal><link linkend="block">block</link></literal> - this is perhaps
937 the single most used action, and is particularly important for ad blocking.
938 This action stops any contact between your browser and any URL patterns
939 that match this action's configuration. It can be used for blocking ads,
940 but also anything that is determined to be unwanted. By itself, it simply
941 stops any communication with the remote server and sends
942 <application>Privoxy</application>'s own built-in BLOCKED page instead to
943 let you now what has happened (with some exceptions, see below).
949 <literal><link linkend="handle-as-image">handle-as-image</link></literal> -
950 tells <application>Privoxy</application> to treat this URL as an image.
951 <application>Privoxy</application>'s default configuration already does this
952 for all common image types (e.g. GIF), but there are many situations where this
953 is not so easy to determine. So we'll force it in these cases. This is particularly
954 important for ad blocking, since only if we know that it's an image of
955 some kind, can we replace it with an image of our choosing, instead of the
956 <application>Privoxy</application> BLOCKED page (which would only result in
957 a <quote>broken image</quote> icon). There are some limitations to this
958 though. For instance, you can't just brute-force an image substitution for
959 an entire HTML page in most situations.
965 <literal><link linkend="handle-as-empty-document">handle-as-empty-document</link></literal> -
966 sends an empty document instead of <application>Privoxy's</application>
967 normal BLOCKED HTML page. This is useful for file types that are neither
968 HTML nor images, such as blocking JavaScript files.
975 linkend="set-image-blocker">set-image-blocker</link></literal> - tells
976 <application>Privoxy</application> what to display in place of an ad image that
977 has hit a block rule. For this to come into play, the URL must match a
978 <literal><link linkend="block">block</link></literal> action somewhere in the
979 configuration, <emphasis>and</emphasis>, it must also match an
980 <literal><link linkend="handle-as-image">handle-as-image</link></literal> action.
983 The configuration options on what to display instead of the ad are:
987 <emphasis>pattern</emphasis> - a checkerboard pattern, so that an ad
988 replacement is obvious. This is the default.
993 <emphasis>blank</emphasis> - A very small empty GIF image is displayed.
994 This is the so-called <quote>invisible</quote> configuration option.
999 <emphasis>http://<URL></emphasis> - A redirect to any image anywhere
1000 of the user's choosing (advanced usage).
1009 Advanced users will eventually want to explore &my-app;
1010 <literal><link linkend="filter">filters</link></literal> as well. Filters
1011 are very different from <literal><link
1012 linkend="block">blocks</link></literal>.
1013 A <quote>block</quote> blocks a site, page, or unwanted contented. Filters
1014 are a way of filtering or modifying what is actually on the page. An example
1015 filter usage: a text replacement of <quote>no-no</quote> for
1016 <quote>nasty-word</quote>. That is a very simple example. This process can be
1017 used for ad blocking, but it is more in the realm of advanced usage and has
1018 some pitfalls to be wary off.
1022 The quickest way to adjust any of these settings is with your browser through
1023 the special <application>Privoxy</application> editor at <ulink
1024 url="http://config.privoxy.org/show-status">http://config.privoxy.org/show-status</ulink>
1025 (shortcut: <ulink url="http://p.p/">http://p.p/show-status</ulink>). This
1026 is an internal page, and does not require Internet access.
1030 Note that as of <application>Privoxy</application> 3.0.7 beta the
1031 action editor is disabled by default. Check the
1032 <ulink url="config.html#ENABLE-EDIT-ACTIONS">enable-edit-actions
1033 section in the configuration file</ulink> to learn why and in which
1034 cases it's safe to enable again.
1038 If you decided to enable the action editor, select the appropriate
1039 <quote>actions</quote> file, and click
1040 <quote><guibutton>Edit</guibutton></quote>. It is best to put personal or
1041 local preferences in <filename>user.action</filename> since this is not
1042 meant to be overwritten during upgrades, and will over-ride the settings in
1043 other files. Here you can insert new <quote>actions</quote>, and URLs for ad
1044 blocking or other purposes, and make other adjustments to the configuration.
1045 <application>Privoxy</application> will detect these changes automatically.
1049 A quick and simple step by step example:
1057 Right click on the ad image to be blocked, then select
1058 <quote><guimenuitem>Copy Link Location</guimenuitem></quote> from the
1066 url="http://config.privoxy.org/show-status">http://config.privoxy.org/show-status</ulink>
1071 Find <filename>user.action</filename> in the top section, and click
1072 on <quote><guibutton>Edit</guibutton></quote>:
1075 <!-- image of editor and actions files selections -->
1077 <figure pgwide="0" float="0"><title>Actions Files in Use</title>
1080 <imagedata fileref="files-in-use.jpg" format="jpg">
1083 <phrase>[ Screenshot of Actions Files in Use ]</phrase>
1092 You should have a section with only
1093 <literal><link linkend="block">block</link></literal> listed under
1094 <quote>Actions:</quote>.
1095 If not, click a <quote><guibutton>Insert new section below</guibutton></quote>
1096 button, and in the new section that just appeared, click the
1097 <guibutton>Edit</guibutton> button right under the word <quote>Actions:</quote>.
1098 This will bring up a list of all actions. Find
1099 <literal><link linkend="block">block</link></literal> near the top, and click
1100 in the <quote>Enabled</quote> column, then <quote><guibutton>Submit</guibutton></quote>
1101 just below the list.
1106 Now, in the <literal><link linkend="block">block</link></literal> actions section,
1107 click the <quote><guibutton>Add</guibutton></quote> button, and paste the URL the
1108 browser got from <quote><guimenuitem>Copy Link Location</guimenuitem></quote>.
1109 Remove the <literal>http://</literal> at the beginning of the URL. Then, click
1110 <quote><guibutton>Submit</guibutton></quote> (or
1111 <quote><guibutton>OK</guibutton></quote> if in a pop-up window).
1116 Now go back to the original page, and press <keycap>SHIFT-Reload</keycap>
1117 (or flush all browser caches). The image should be gone now.
1125 This is a very crude and simple example. There might be good reasons to use a
1126 wildcard pattern match to include potentially similar images from the same
1127 site. For a more extensive explanation of <quote>patterns</quote>, and
1128 the entire actions concept, see <link linkend="actions-file">the Actions
1133 For advanced users who want to hand edit their config files, you might want
1134 to now go to the <link linkend="act-examples">Actions Files Tutorial</link>.
1135 The ideas explained therein also apply to the web-based editor.
1138 There are also various
1139 <link linkend="filter">filters</link> that can be used for ad blocking
1140 (filters are a special subset of actions). These
1141 fall into the <quote>advanced</quote> usage category, and are explained in
1142 depth in later sections.
1149 <!-- ~ End section ~ -->
1152 <!-- ~~~~~ New section ~~~~~ -->
1153 <sect1 id="startup">
1154 <title>Starting Privoxy</title>
1156 Before launching <application>Privoxy</application> for the first time, you
1157 will want to configure your browser(s) to use
1158 <application>Privoxy</application> as a HTTP and HTTPS (SSL)
1159 <ulink url="http://en.wikipedia.org/wiki/Proxy_server">proxy</ulink>. The default is
1160 127.0.0.1 (or localhost) for the proxy address, and port 8118 (earlier versions
1161 used port 8000). This is the one configuration step <emphasis>that must be done
1165 Please note that <application>Privoxy</application> can only proxy HTTP and
1166 HTTPS traffic. It will not work with FTP or other protocols.
1169 <!-- image of Mozilla Proxy configuration -->
1171 <figure pgwide="0" float="0"><title>Proxy Configuration Showing
1172 Mozilla/Netscape HTTP and HTTPS (SSL) Settings</title>
1175 <imagedata fileref="proxy_setup.jpg" format="jpg">
1178 <phrase>[ Screenshot of Mozilla Proxy Configuration ]</phrase>
1186 With <application>Firefox</application>, this is typically set under:
1190 <guibutton>Tools</guibutton> -> <guibutton>Options</guibutton> -> <guibutton>Advanced</guibutton> -> <guibutton>Network</guibutton> -><guibutton>Connection</guibutton> -> <guibutton>Settings</guibutton>
1195 Or optionally on some platforms:
1199 <guibutton>Edit</guibutton> -> <guibutton>Preferences</guibutton> -> <guibutton>General</guibutton> -> <guibutton>Connection Settings</guibutton> -> <guibutton>Manual Proxy Configuration</guibutton>
1205 With <application>Netscape</application> (and
1206 <application>Mozilla</application>), this can be set under:
1211 <!-- Mix ascii and gui art, something for everybody -->
1212 <!-- spacing on this is tricky -->
1213 <guibutton>Edit</guibutton> -> <guibutton>Preferences</guibutton> -> <guibutton>Advanced</guibutton> -> <guibutton>Proxies</guibutton> -> <guibutton>HTTP Proxy</guibutton>
1218 For <application>Internet Explorer v.5-7</application>:
1222 <guibutton>Tools</guibutton> -> <guibutton>Internet Options</guibutton> -> <guibutton>Connections</guibutton> -> <guibutton>LAN Settings</guibutton>
1226 Then, check <quote>Use Proxy</quote> and fill in the appropriate info
1227 (Address: 127.0.0.1, Port: 8118). Include HTTPS (SSL), if you want HTTPS
1228 proxy support too (sometimes labeled <quote>Secure</quote>). Make sure any
1229 checkboxes like <quote>Use the same proxy server for all protocols</quote> is
1230 <emphasis>UNCHECKED</emphasis>. You want only HTTP and HTTPS (SSL)!
1233 <!-- image of IE Proxy configuration -->
1235 <figure pgwide="0" float="0"><title>Proxy Configuration Showing
1236 Internet Explorer HTTP and HTTPS (Secure) Settings</title>
1239 <imagedata fileref="proxy2.jpg" format="jpg">
1242 <phrase>[ Screenshot of IE Proxy Configuration ]</phrase>
1250 After doing this, flush your browser's disk and memory caches to force a
1251 re-reading of all pages and to get rid of any ads that may be cached. Remove
1252 any <ulink url="http://en.wikipedia.org/wiki/Browser_cookie">cookies</ulink>,
1253 if you want <application>Privoxy</application> to manage that. You are now
1254 ready to start enjoying the benefits of using
1255 <application>Privoxy</application>!
1259 <application>Privoxy</application> itself is typically started by specifying the
1260 main configuration file to be used on the command line. If no configuration
1261 file is specified on the command line, <application>Privoxy</application>
1262 will look for a file named <filename>config</filename> in the current
1263 directory. Except on Win32 where it will try <filename>config.txt</filename>.
1266 <sect2 id="start-redhat">
1267 <title>Red Hat and Fedora</title>
1269 A default Red Hat installation may not start &my-app; upon boot. It will use
1270 the file <filename>/etc/privoxy/config</filename> as its main configuration
1275 # /etc/rc.d/init.d/privoxy start
1283 # service privoxy start
1288 <sect2 id="start-debian">
1289 <title>Debian</title>
1291 We use a script. Note that Debian typically starts &my-app; upon booting per
1292 default. It will use the file
1293 <filename>/etc/privoxy/config</filename> as its main configuration
1298 # /etc/init.d/privoxy start
1303 <sect2 id="start-windows">
1304 <title>Windows</title>
1306 Click on the &my-app; Icon to start <application>Privoxy</application>. If no configuration file is
1307 specified on the command line, <application>Privoxy</application> will look
1308 for a file named <filename>config.txt</filename>. Note that Windows will
1309 automatically start &my-app; when the system starts if you chose that option
1313 <application>Privoxy</application> can run with full Windows service functionality.
1314 On Windows only, the &my-app; program has two new command line arguments
1315 to install and uninstall &my-app; as a service. See the
1316 <link linkend="installation-pack-win">Windows Installation
1317 instructions</link> for details.
1321 <sect2 id="start-unices">
1322 <title>Solaris, NetBSD, FreeBSD, HP-UX and others</title>
1324 Example Unix startup command:
1328 # /usr/sbin/privoxy /etc/privoxy/config
1333 <sect2 id="start-os2">
1336 During installation, <application>Privoxy</application> is configured to
1337 start automatically when the system restarts. You can start it manually by
1338 double-clicking on the <application>Privoxy</application> icon in the
1339 <application>Privoxy</application> folder.
1343 <sect2 id="start-macosx">
1344 <title>Mac OS X</title>
1346 After downloading the privoxy software, unzip the downloaded file by
1347 double-clicking on the zip file icon. Then, double-click on the
1348 installer package icon and follow the installation process.
1351 The privoxy service will automatically start after a successful
1352 installation. In addition, the privoxy service will automatically
1353 start every time your computer starts up.
1356 To prevent the privoxy service from automatically starting when your
1357 computer starts up, remove or rename the folder named
1358 /Library/StartupItems/Privoxy.
1361 A simple application named Privoxy Utility has been created which
1362 enables administrators to easily start and stop the privoxy service.
1365 In addition, the Privoxy Utility presents a simple way for
1366 administrators to edit the various privoxy config files. A method
1367 to uninstall the software is also available.
1370 An administrator username and password must be supplied in order for
1371 the Privoxy Utility to perform any of the tasks.
1374 During installation, <application>Privoxy</application> is configured to
1375 start automatically when the system restarts. To start &my-app; manually,
1376 double-click on the <literal>StartPrivoxy.command</literal> icon in the
1377 <literal>/Library/Privoxy</literal> folder. Or, type this command
1382 /Library/Privoxy/StartPrivoxy.command
1386 You will be prompted for the administrator password.
1391 <sect2 id="start-amigaos">
1392 <title>AmigaOS</title>
1394 Start <application>Privoxy</application> (with RUN <>NIL:) in your
1395 <filename>startnet</filename> script (AmiTCP), in
1396 <filename>s:user-startup</filename> (RoadShow), as startup program in your
1397 startup script (Genesis), or as startup action (Miami and MiamiDx).
1398 <application>Privoxy</application> will automatically quit when you quit your
1399 TCP/IP stack (just ignore the harmless warning your TCP/IP stack may display that
1400 <application>Privoxy</application> is still running).
1404 <sect2 id="start-gentoo">
1405 <title>Gentoo</title>
1407 A script is again used. It will use the file <filename>/etc/privoxy/config
1408 </filename> as its main configuration file.
1412 /etc/init.d/privoxy start
1416 Note that <application>Privoxy</application> is not automatically started at
1417 boot time by default. You can change this with the <literal>rc-update</literal>
1422 rc-update add privoxy default
1430 See the section <link linkend="cmdoptions">Command line options</link> for
1434 must find a better place for this paragraph
1437 The included default configuration files should give a reasonable starting
1438 point. Most of the per site configuration is done in the
1439 <ulink url="actions-file.html"><quote>actions</quote></ulink> files. These are
1440 where various cookie actions are defined, ad and banner blocking, and other
1441 aspects of <application>Privoxy</application> configuration. There are several
1442 such files included, with varying levels of aggressiveness.
1446 You will probably want to keep an eye out for sites for which you may prefer
1447 persistent cookies, and add these to your actions configuration as needed. By
1448 default, most of these will be accepted only during the current browser
1449 session (aka <quote>session cookies</quote>), unless you add them to the
1450 configuration. If you want the browser to handle this instead, you will need
1451 to edit <filename>user.action</filename> (or through the web based interface)
1452 and disable this feature. If you use more than one browser, it would make
1453 more sense to let <application>Privoxy</application> handle this. In which
1454 case, the browser(s) should be set to accept all cookies.
1458 Another feature where you will probably want to define exceptions for trusted
1459 sites is the popup-killing (through the <ulink
1460 url="actions-file.html#KILL-POPUPS"><quote>+kill-popups</quote></ulink> and
1462 url="actions-file.html#FILTER-POPUPS"><quote>+filter{popups}</quote></ulink>
1463 actions), because your favorite shopping, banking, or leisure site may need
1464 popups (explained below).
1468 <application>Privoxy</application> does not support all of the optional HTTP/1.1
1469 features yet. In the unlikely event that you experience inexplicable problems
1470 with browsers that use HTTP/1.1 per default
1471 (like <application>Mozilla</application> or recent versions of I.E.), you might
1472 try to force HTTP/1.0 compatibility. For Mozilla, look under <literal>Edit ->
1473 Preferences -> Debug -> Networking</literal>.
1474 Alternatively, set the <quote>+downgrade-http-version</quote> config option in
1475 <filename>default.action</filename> which will downgrade your browser's HTTP
1476 requests from HTTP/1.1 to HTTP/1.0 before processing them.
1480 After running <application>Privoxy</application> for a while, you can
1481 start to fine tune the configuration to suit your personal, or site,
1482 preferences and requirements. There are many, many aspects that can
1483 be customized. <quote>Actions</quote>
1484 can be adjusted by pointing your browser to
1485 <ulink url="http://config.privoxy.org/">http://config.privoxy.org/</ulink>
1486 (shortcut: <ulink url="http://p.p/">http://p.p/</ulink>),
1487 and then follow the link to <quote>View & Change the Current Configuration</quote>.
1488 (This is an internal page and does not require Internet access.)
1492 In fact, various aspects of <application>Privoxy</application>
1493 configuration can be viewed from this page, including
1494 current configuration parameters, source code version numbers,
1495 the browser's request headers, and <quote>actions</quote> that apply
1496 to a given URL. In addition to the actions file
1497 editor mentioned above, <application>Privoxy</application> can also
1498 be turned <quote>on</quote> and <quote>off</quote> (toggled) from this page.
1502 If you encounter problems, try loading the page without
1503 <application>Privoxy</application>. If that helps, enter the URL where
1504 you have the problems into <ulink url="http://p.p/show-url-info">the browser
1505 based rule tracing utility</ulink>. See which rules apply and why, and
1506 then try turning them off for that site one after the other, until the problem
1507 is gone. When you have found the culprit, you might want to turn the rest on
1512 If the above paragraph sounds gibberish to you, you might want to <link
1513 linkend="actions-file">read more about the actions concept</link>
1514 or even dive deep into the <link linkend="actionsanat">Appendix
1519 If you can't get rid of the problem at all, think you've found a bug in
1520 Privoxy, want to propose a new feature or smarter rules, please see the
1521 section <link linkend="contact"><quote>Contacting the
1522 Developers</quote></link> below.
1527 <!-- ~~~~~ New section ~~~~~ -->
1528 <sect2 id="cmdoptions">
1529 <title>Command Line Options</title>
1531 <application>Privoxy</application> may be invoked with the following
1532 command-line options:
1540 <emphasis>--version</emphasis>
1543 Print version info and exit. Unix only.
1548 <emphasis>--help</emphasis>
1551 Print short usage info and exit. Unix only.
1556 <emphasis>--no-daemon</emphasis>
1559 Don't become a daemon, i.e. don't fork and become process group
1560 leader, and don't detach from controlling tty. Unix only.
1565 <emphasis>--pidfile FILE</emphasis>
1568 On startup, write the process ID to <emphasis>FILE</emphasis>. Delete the
1569 <emphasis>FILE</emphasis> on exit. Failure to create or delete the
1570 <emphasis>FILE</emphasis> is non-fatal. If no <emphasis>FILE</emphasis>
1571 option is given, no PID file will be used. Unix only.
1576 <emphasis>--user USER[.GROUP]</emphasis>
1579 After (optionally) writing the PID file, assume the user ID of
1580 <emphasis>USER</emphasis>, and if included the GID of GROUP. Exit if the
1581 privileges are not sufficient to do so. Unix only.
1586 <emphasis>--chroot</emphasis>
1589 Before changing to the user ID given in the <emphasis>--user</emphasis> option,
1590 chroot to that user's home directory, i.e. make the kernel pretend to the &my-app;
1591 process that the directory tree starts there. If set up carefully, this can limit
1592 the impact of possible vulnerabilities in &my-app; to the files contained in that hierarchy.
1598 <emphasis>--pre-chroot-nslookup hostname</emphasis>
1601 Specifies a hostname to look up before doing a chroot. On some systems, initializing the
1602 resolver library involves reading config files from /etc and/or loading additional shared
1603 libraries from /lib. On these systems, doing a hostname lookup before the chroot reduces
1604 the number of files that must be copied into the chroot tree.
1607 For fastest startup speed, a good value is a hostname that is not in /etc/hosts but that
1608 your local name server (listed in /etc/resolv.conf) can resolve without recursion
1609 (that is, without having to ask any other name servers). The hostname need not exist,
1610 but if it doesn't, an error message (which can be ignored) will be output.
1616 <emphasis>configfile</emphasis>
1619 If no <emphasis>configfile</emphasis> is included on the command line,
1620 <application>Privoxy</application> will look for a file named
1621 <quote>config</quote> in the current directory (except on Win32
1622 where it will look for <quote>config.txt</quote> instead). Specify
1623 full path to avoid confusion. If no config file is found,
1624 <application>Privoxy</application> will fail to start.
1632 On <application>MS Windows</application> only there are two additional
1633 command-line options to allow <application>Privoxy</application> to install and
1634 run as a <emphasis>service</emphasis>. See the
1635 <link linkend="installation-pack-win">Window Installation section</link>
1643 <!-- ~ End section ~ -->
1646 <!-- ~~~~~ New section ~~~~~ -->
1647 <sect1 id="configuration"><title>Privoxy Configuration</title>
1649 All <application>Privoxy</application> configuration is stored
1650 in text files. These files can be edited with a text editor.
1651 Many important aspects of <application>Privoxy</application> can
1652 also be controlled easily with a web browser.
1656 <!-- ~~~~~ New section ~~~~~ -->
1659 <title>Controlling Privoxy with Your Web Browser</title>
1661 <application>Privoxy</application>'s user interface can be reached through the special
1662 URL <ulink url="http://config.privoxy.org/">http://config.privoxy.org/</ulink>
1663 (shortcut: <ulink url="http://p.p/">http://p.p/</ulink>),
1664 which is a built-in page and works without Internet access.
1665 You will see the following section:
1669 <!-- Needs to be put in a table and colorized -->
1672 <bridgehead renderas="sect2"> Privoxy Menu</bridgehead>
1676 ▪ <ulink url="http://config.privoxy.org/show-status">View & change the current configuration</ulink>
1679 ▪ <ulink url="http://config.privoxy.org/show-version">View the source code version numbers</ulink>
1682 ▪ <ulink url="http://config.privoxy.org/show-request">View the request headers.</ulink>
1685 ▪ <ulink url="http://config.privoxy.org/show-url-info">Look up which actions apply to a URL and why</ulink>
1688 ▪ <ulink url="http://config.privoxy.org/toggle">Toggle Privoxy on or off</ulink>
1691 ▪ <ulink url="http://www.privoxy.org/
1692 &p-version;/user-manual/">Documentation</ulink>
1700 This should be self-explanatory. Note the first item leads to an editor for the
1701 <link linkend="actions-file">actions files</link>, which is where the ad, banner,
1702 cookie, and URL blocking magic is configured as well as other advanced features of
1703 <application>Privoxy</application>. This is an easy way to adjust various
1704 aspects of <application>Privoxy</application> configuration. The actions
1705 file, and other configuration files, are explained in detail below.
1709 <quote>Toggle Privoxy On or Off</quote> is handy for sites that might
1710 have problems with your current actions and filters. You can in fact use
1711 it as a test to see whether it is <application>Privoxy</application>
1712 causing the problem or not. <application>Privoxy</application> continues
1713 to run as a proxy in this case, but all manipulation is disabled, i.e.
1714 <application>Privoxy</application> acts like a normal forwarding proxy. There
1715 is even a toggle <link linkend="bookmarklets">Bookmarklet</link> offered, so
1716 that you can toggle <application>Privoxy</application> with one click from
1721 Note that several of the features described above are disabled by default
1722 in <application>Privoxy</application> 3.0.7 beta and later.
1724 <ulink url="config.html">configuration file</ulink> to learn why
1725 and in which cases it's safe to enable them again.
1730 <!-- ~ End section ~ -->
1735 <!-- ~~~~~ New section ~~~~~ -->
1737 <sect2 id="confoverview">
1738 <title>Configuration Files Overview</title>
1740 For Unix, *BSD and Linux, all configuration files are located in
1741 <filename>/etc/privoxy/</filename> by default. For MS Windows, OS/2, and
1742 AmigaOS these are all in the same directory as the
1743 <application>Privoxy</application> executable. <![%p-not-stable;[ The name
1744 and number of configuration files has changed from previous versions, and is
1745 subject to change as development progresses.]]>
1749 The installed defaults provide a reasonable starting point, though
1750 some settings may be aggressive by some standards. For the time being, the
1751 principle configuration files are:
1759 The <link linkend="config">main configuration file</link> is named <filename>config</filename>
1760 on Linux, Unix, BSD, OS/2, and AmigaOS and <filename>config.txt</filename>
1761 on Windows. This is a required file.
1767 <filename>default.action</filename> (the main <link linkend="actions-file">actions file</link>)
1768 is used to define which <quote>actions</quote> relating to banner-blocking, images, pop-ups,
1769 content modification, cookie handling etc should be applied by default. It also defines many
1770 exceptions (both positive and negative) from this default set of actions that enable
1771 <application>Privoxy</application> to selectively eliminate the junk, and only the junk, on
1772 as many websites as possible.
1775 Multiple actions files may be defined in <filename>config</filename>. These
1776 are processed in the order they are defined. Local customizations and locally
1777 preferred exceptions to the default policies as defined in
1778 <filename>default.action</filename> (which you will most probably want
1779 to define sooner or later) are probably best applied in
1780 <filename>user.action</filename>, where you can preserve them across
1781 upgrades. <filename>standard.action</filename> is only for
1782 <application>Privoxy's</application> internal use.
1785 There is also a web based editor that can be accessed from
1787 url="http://config.privoxy.org/show-status">http://config.privoxy.org/show-status</ulink>
1789 url="http://p.p/show-status">http://p.p/show-status</ulink>) for the
1790 various actions files.
1796 <quote>Filter files</quote> (the <link linkend="filter-file">filter
1797 file</link>) can be used to re-write the raw page content, including
1798 viewable text as well as embedded HTML and JavaScript, and whatever else
1799 lurks on any given web page. The filtering jobs are only pre-defined here;
1800 whether to apply them or not is up to the actions files.
1801 <filename>default.filter</filename> includes various filters made
1802 available for use by the developers. Some are much more intrusive than
1803 others, and all should be used with caution. You may define additional
1804 filter files in <filename>config</filename> as you can with
1805 actions files. We suggest <filename>user.filter</filename> for any
1806 locally defined filters or customizations.
1814 The syntax of the configuration and filter files may change between different
1815 Privoxy versions, unfortunately some enhancements cost backwards compatibility.
1816 <!-- Add link to documentation-->
1820 All files use the <quote><literal>#</literal></quote> character to denote a
1821 comment (the rest of the line will be ignored) and understand line continuation
1822 through placing a backslash ("<literal>\</literal>") as the very last character
1823 in a line. If the <literal>#</literal> is preceded by a backslash, it looses
1824 its special function. Placing a <literal>#</literal> in front of an otherwise
1825 valid configuration line to prevent it from being interpreted is called "commenting
1826 out" that line. Blank lines are ignored.
1830 The actions files and filter files
1831 can use Perl style <link linkend="regex">regular expressions</link> for
1832 maximum flexibility.
1836 After making any changes, there is no need to restart
1837 <application>Privoxy</application> in order for the changes to take
1838 effect. <application>Privoxy</application> detects such changes
1839 automatically. Note, however, that it may take one or two additional
1840 requests for the change to take effect. When changing the listening address
1841 of <application>Privoxy</application>, these <quote>wake up</quote> requests
1842 must obviously be sent to the <emphasis>old</emphasis> listening address.
1847 While under development, the configuration content is subject to change.
1848 The below documentation may not be accurate by the time you read this.
1849 Also, what constitutes a <quote>default</quote> setting, may change, so
1850 please check all your configuration files on important issues.
1856 <!-- ~ End section ~ -->
1859 <!-- ~~~~~~~~ New section Header ~~~~~~~~~ -->
1861 <!-- **************************************************** -->
1862 <!-- Include config.sgml here -->
1863 <!-- This is where the entire config file is detailed. -->
1865 <!-- end include -->
1868 <!-- ~ End section ~ -->
1872 <!-- ~~~~~~~~ New section Header ~~~~~~~~~ -->
1874 <sect1 id="actions-file"><title>Actions Files</title>
1877 The actions files are used to define what <emphasis>actions</emphasis>
1878 <application>Privoxy</application> takes for which URLs, and thus determines
1879 how ad images, cookies and various other aspects of HTTP content and
1880 transactions are handled, and on which sites (or even parts thereof).
1881 There are a number of such actions, with a wide range of functionality.
1882 Each action does something a little different.
1883 These actions give us a veritable arsenal of tools with which to exert
1884 our control, preferences and independence. Actions can be combined so that
1885 their effects are aggregated when applied against a given set of URLs.
1889 are three action files included with <application>Privoxy</application> with
1897 <filename>default.action</filename> - is the primary action file
1898 that sets the initial values for all actions. It is intended to
1899 provide a base level of functionality for
1900 <application>Privoxy's</application> array of features. So it is
1901 a set of broad rules that should work reasonably well as-is for most users.
1902 This is the file that the developers are keeping updated, and <link
1903 linkend="installation-keepupdated">making available to users</link>.
1904 The user's preferences as set in <filename>standard.action</filename>,
1905 e.g. either <literal>Cautious</literal> (the default),
1906 <literal>Medium</literal>, or <literal>Advanced</literal> (see
1912 <filename>user.action</filename> - is intended to be for local site
1913 preferences and exceptions. As an example, if your ISP or your bank
1914 has specific requirements, and need special handling, this kind of
1915 thing should go here. This file will not be upgraded.
1920 <filename>standard.action</filename> - is used only by the web based editor
1921 at <ulink url="http://config.privoxy.org/edit-actions-list?f=default">
1922 http://config.privoxy.org/edit-actions-list?f=default</ulink>,
1923 to set various pre-defined sets of rules for the default actions section
1924 in <filename>default.action</filename>.
1927 <guibutton>Edit</guibutton> <guibutton>Set to Cautious</guibutton> <guibutton>Set to Medium</guibutton> <guibutton>Set to Advanced</guibutton>
1930 These have increasing levels of aggressiveness <emphasis>and have no
1931 influence on your browsing unless you select them explicitly in the
1932 editor</emphasis>. A default installation should be pre-set to
1933 <literal>Cautious</literal> (versions prior to 3.0.5 were set to
1934 <literal>Medium</literal>). New users should try this for a while before
1935 adjusting the settings to more aggressive levels. The more aggressive
1936 the settings, then the more likelihood there is of problems such as sites
1937 not working as they should.
1940 The <guibutton>Edit</guibutton> button allows you to turn each
1941 action on/off individually for fine-tuning. The <guibutton>Cautious</guibutton>
1942 button changes the actions list to low/safe settings which will activate
1943 ad blocking and a minimal set of &my-app;'s features, and subsequently
1944 there will be less of a chance for accidental problems. The
1945 <guibutton>Medium</guibutton> button sets the list to a medium level of
1946 other features and a low level set of privacy features. The
1947 <guibutton>Advanced</guibutton> button sets the list to a high level of
1948 ad blocking and medium level of privacy. See the chart below. The latter
1949 three buttons over-ride any changes via with the
1950 <guibutton>Edit</guibutton> button. More fine-tuning can be done in the
1951 lower sections of this internal page.
1954 It is not recommend to edit the <filename>standard.action</filename> file
1958 The default profiles, and their associated actions, as pre-defined in
1959 <filename>standard.action</filename> are<!-- different than this table which is out of date -->:
1962 <table frame=all><title>Default Configurations</title>
1963 <tgroup cols=4 align=left colsep=1 rowsep=1>
1964 <colspec colname=c1>
1965 <colspec colname=c2>
1966 <colspec colname=c3>
1967 <colspec colname=c4>
1970 <entry>Feature</entry>
1971 <entry>Cautious</entry>
1972 <entry>Medium</entry>
1973 <entry>Advanced</entry>
1978 <!-- <entry>f1</entry> -->
1979 <!-- <entry>f2</entry> -->
1980 <!-- <entry>f3</entry> -->
1981 <!-- <entry>f4</entry> -->
1987 <entry>Ad-blocking Aggressiveness</entry>
1988 <entry>medium</entry>
1994 <entry>Ad-filtering by size</entry>
2001 <entry>Ad-filtering by link</entry>
2007 <entry>Pop-up killing</entry>
2008 <entry>blocks only</entry>
2009 <entry>blocks only</entry>
2010 <entry>blocks only</entry>
2014 <entry>Privacy Features</entry>
2016 <entry>medium</entry>
2017 <entry>medium/high</entry>
2021 <entry>Cookie handling</entry>
2023 <entry>session-only</entry>
2028 <entry>Referer forging</entry>
2036 <entry>GIF de-animation</entry>
2044 <entry>Fast redirects</entry>
2051 <entry>HTML taming</entry>
2058 <entry>JavaScript taming</entry>
2065 <entry>Web-bug killing</entry>
2072 <entry>Image tag reordering</entry>
2088 The list of actions files to be used are defined in the main configuration
2089 file, and are processed in the order they are defined (e.g.
2090 <filename>default.action</filename> is typically processed before
2091 <filename>user.action</filename>). The content of these can all be viewed and
2093 url="http://config.privoxy.org/show-status">http://config.privoxy.org/show-status</ulink>.
2094 The over-riding principle when applying actions, is that the last action that
2095 matches a given URL wins. The broadest, most general rules go first
2096 (defined in <filename>default.action</filename>),
2097 followed by any exceptions (typically also in
2098 <filename>default.action</filename>), which are then followed lastly by any
2099 local preferences (typically in <emphasis>user</emphasis><filename>.action</filename>).
2100 Generally, <filename>user.action</filename> has the last word.
2104 An actions file typically has multiple sections. If you want to use
2105 <quote>aliases</quote> in an actions file, you have to place the (optional)
2106 <link linkend="aliases">alias section</link> at the top of that file.
2107 Then comes the default set of rules which will apply universally to all
2108 sites and pages (be <emphasis>very careful</emphasis> with using such a
2109 universal set in <filename>user.action</filename> or any other actions file after
2110 <filename>default.action</filename>, because it will override the result
2111 from consulting any previous file). And then below that,
2112 exceptions to the defined universal policies. You can regard
2113 <filename>user.action</filename> as an appendix to <filename>default.action</filename>,
2114 with the advantage that it is a separate file, which makes preserving your
2115 personal settings across <application>Privoxy</application> upgrades easier.
2119 Actions can be used to block anything you want, including ads, banners, or
2120 just some obnoxious URL whose content you would rather not see. Cookies can be accepted
2121 or rejected, or accepted only during the current browser session (i.e. not
2122 written to disk), content can be modified, some JavaScripts tamed, user-tracking
2123 fooled, and much more. See below for a <link linkend="actions">complete list
2127 <!-- ~~~~~ New section ~~~~~ -->
2129 <title>Finding the Right Mix</title>
2131 Note that some <link linkend="actions">actions</link>, like cookie suppression
2132 or script disabling, may render some sites unusable that rely on these
2133 techniques to work properly. Finding the right mix of actions is not always easy and
2134 certainly a matter of personal taste. And, things can always change, requiring
2135 refinements in the configuration. In general, it can be said that the more
2136 <quote>aggressive</quote> your default settings (in the top section of the
2137 actions file) are, the more exceptions for <quote>trusted</quote> sites you
2138 will have to make later. If, for example, you want to crunch all cookies per
2139 default, you'll have to make exceptions from that rule for sites that you
2140 regularly use and that require cookies for actually useful purposes, like maybe
2141 your bank, favorite shop, or newspaper.
2145 We have tried to provide you with reasonable rules to start from in the
2146 distribution actions files. But there is no general rule of thumb on these
2147 things. There just are too many variables, and sites are constantly changing.
2148 Sooner or later you will want to change the rules (and read this chapter again :).
2152 <!-- ~~~~~ New section ~~~~~ -->
2154 <title>How to Edit</title>
2156 The easiest way to edit the actions files is with a browser by
2157 using our browser-based editor, which can be reached from <ulink
2158 url="http://config.privoxy.org/show-status">http://config.privoxy.org/show-status</ulink>.
2159 Note: the config file option <link
2160 linkend="enable-edit-actions">enable-edit-actions</link> must be enabled for
2161 this to work. The editor allows both fine-grained control over every single
2162 feature on a per-URL basis, and easy choosing from wholesale sets of defaults
2163 like <quote>Cautious</quote>, <quote>Medium</quote> or
2164 <quote>Advanced</quote>. Warning: the <quote>Advanced</quote> setting is more
2165 aggressive, and will be more likely to cause problems for some sites.
2166 Experienced users only!
2170 If you prefer plain text editing to GUIs, you can of course also directly edit the
2171 the actions files with your favorite text editor. Look at
2172 <filename>default.action</filename> which is richly commented with many
2178 <sect2 id="actions-apply">
2179 <title>How Actions are Applied to Requests</title>
2181 Actions files are divided into sections. There are special sections,
2182 like the <quote><link linkend="aliases">alias</link></quote> sections which will
2183 be discussed later. For now let's concentrate on regular sections: They have a
2184 heading line (often split up to multiple lines for readability) which consist
2185 of a list of actions, separated by whitespace and enclosed in curly braces.
2186 Below that, there is a list of URL and tag patterns, each on a separate line.
2190 To determine which actions apply to a request, the URL of the request is
2191 compared to all URL patterns in each <quote>action file</quote>.
2192 Every time it matches, the list of applicable actions for the request is
2193 incrementally updated, using the heading of the section in which the
2194 pattern is located. The same is done again for tags and tag patterns later on.
2198 If multiple applying sections set the same action differently,
2199 the last match wins. If not, the effects are aggregated.
2200 E.g. a URL might match a regular section with a heading line of <literal>{
2201 +<link linkend="handle-as-image">handle-as-image</link> }</literal>,
2202 then later another one with just <literal>{
2203 +<link linkend="block">block</link> }</literal>, resulting
2204 in <emphasis>both</emphasis> actions to apply. And there may well be
2205 cases where you will want to combine actions together. Such a section then
2211 { +<literal>handle-as-image</literal> +<literal>block{Banner ads.}</literal> }
2212 # Block these as if they were images. Send no block page.
2214 media.example.com/.*banners
2215 .example.com/images/ads/</screen>
2219 You can trace this process for URL patterns and any given URL by visiting <ulink
2220 url="http://config.privoxy.org/show-url-info">http://config.privoxy.org/show-url-info</ulink>.
2224 Examples and more detail on this is provided in the Appendix, <link linkend="ACTIONSANAT">
2225 Troubleshooting: Anatomy of an Action</link> section.
2229 <!-- ~~~~~ New section ~~~~~ -->
2230 <sect2 id="af-patterns">
2231 <title>Patterns</title>
2233 As mentioned, <application>Privoxy</application> uses <quote>patterns</quote>
2234 to determine what <emphasis>actions</emphasis> might apply to which sites and
2235 pages your browser attempts to access. These <quote>patterns</quote> use wild
2236 card type <emphasis>pattern</emphasis> matching to achieve a high degree of
2237 flexibility. This allows one expression to be expanded and potentially match
2238 against many similar patterns.
2242 Generally, an URL pattern has the form
2243 <literal><domain>/<path></literal>, where both the
2244 <literal><domain></literal> and <literal><path></literal> are
2245 optional. (This is why the special <literal>/</literal> pattern matches all
2246 URLs). Note that the protocol portion of the URL pattern (e.g.
2247 <literal>http://</literal>) should <emphasis>not</emphasis> be included in
2248 the pattern. This is assumed already!
2251 The pattern matching syntax is different for the domain and path parts of
2252 the URL. The domain part uses a simple globbing type matching technique,
2253 while the path part uses a more flexible
2254 <ulink url="http://en.wikipedia.org/wiki/Regular_expressions"><quote>Regular
2255 Expressions (PCRE)</quote></ulink> based syntax.
2260 <term><literal>www.example.com/</literal></term>
2263 is a domain-only pattern and will match any request to <literal>www.example.com</literal>,
2264 regardless of which document on that server is requested. So ALL pages in
2265 this domain would be covered by the scope of this action. Note that a
2266 simple <literal>example.com</literal> is different and would NOT match.
2271 <term><literal>www.example.com</literal></term>
2274 means exactly the same. For domain-only patterns, the trailing <literal>/</literal> may
2280 <term><literal>www.example.com/index.html$</literal></term>
2283 matches all the documents on <literal>www.example.com</literal>
2284 whose name starts with <literal>/index.html</literal>.
2289 <term><literal>www.example.com/index.html$</literal></term>
2292 matches only the single document <literal>/index.html</literal>
2293 on <literal>www.example.com</literal>.
2298 <term><literal>/index.html$</literal></term>
2301 matches the document <literal>/index.html</literal>, regardless of the domain,
2302 i.e. on <emphasis>any</emphasis> web server anywhere.
2307 <term><literal>index.html</literal></term>
2310 matches nothing, since it would be interpreted as a domain name and
2311 there is no top-level domain called <literal>.html</literal>. So its
2319 <!-- ~~~~~ New section ~~~~~ -->
2320 <sect3><title>The Domain Pattern</title>
2323 The matching of the domain part offers some flexible options: if the
2324 domain starts or ends with a dot, it becomes unanchored at that end.
2330 <term><literal>.example.com</literal></term>
2333 matches any domain with first-level domain <literal>com</literal>
2334 and second-level domain <literal>example</literal>.
2335 For example <literal>www.example.com</literal>,
2336 <literal>example.com</literal> and <literal>foo.bar.baz.example.com</literal>.
2337 Note that it wouldn't match if the second-level domain was <literal>another-example</literal>.
2342 <term><literal>www.</literal></term>
2345 matches any domain that <emphasis>STARTS</emphasis> with
2346 <literal>www.</literal> (It also matches the domain
2347 <literal>www</literal> but most of the time that doesn't matter.)
2352 <term><literal>.example.</literal></term>
2355 matches any domain that <emphasis>CONTAINS</emphasis> <literal>.example.</literal>.
2356 And, by the way, also included would be any files or documents that exist
2357 within that domain since no path limitations are specified. (Correctly
2358 speaking: It matches any FQDN that contains <literal>example</literal> as
2359 a domain.) This might be <literal>www.example.com</literal>,
2360 <literal>news.example.de</literal>, or
2361 <literal>www.example.net/cgi/testing.pl</literal> for instance. All these
2369 Additionally, there are wild-cards that you can use in the domain names
2370 themselves. These work similarly to shell globbing type wild-cards:
2371 <quote>*</quote> represents zero or more arbitrary characters (this is
2373 <ulink url="http://en.wikipedia.org/wiki/Regular_expressions"><quote>Regular
2374 Expression</quote></ulink> based syntax of <quote>.*</quote>),
2375 <quote>?</quote> represents any single character (this is equivalent to the
2376 regular expression syntax of a simple <quote>.</quote>), and you can define
2377 <quote>character classes</quote> in square brackets which is similar to
2378 the same regular expression technique. All of this can be freely mixed:
2383 <term><literal>ad*.example.com</literal></term>
2386 matches <quote>adserver.example.com</quote>,
2387 <quote>ads.example.com</quote>, etc but not <quote>sfads.example.com</quote>
2392 <term><literal>*ad*.example.com</literal></term>
2395 matches all of the above, and then some.
2400 <term><literal>.?pix.com</literal></term>
2403 matches <literal>www.ipix.com</literal>,
2404 <literal>pictures.epix.com</literal>, <literal>a.b.c.d.e.upix.com</literal> etc.
2409 <term><literal>www[1-9a-ez].example.c*</literal></term>
2412 matches <literal>www1.example.com</literal>,
2413 <literal>www4.example.cc</literal>, <literal>wwwd.example.cy</literal>,
2414 <literal>wwwz.example.com</literal> etc., but <emphasis>not</emphasis>
2415 <literal>wwww.example.com</literal>.
2422 While flexible, this is not the sophistication of full regular expression based syntax.
2427 <!-- ~ End section ~ -->
2430 <!-- ~~~~~ New section ~~~~~ -->
2431 <sect3><title>The Path Pattern</title>
2434 <application>Privoxy</application> uses Perl compatible (PCRE)
2435 <ulink url="http://en.wikipedia.org/wiki/Regular_expressions"><quote>Regular
2436 Expression</quote></ulink> based syntax
2437 (through the <ulink url="http://www.pcre.org/">PCRE</ulink> library) for
2438 matching the path portion (after the slash), and is thus more flexible.
2442 There is an <link linkend="regex">Appendix</link> with a brief quick-start into regular
2443 expressions, and full (very technical) documentation on PCRE regex syntax is available on-line
2444 at <ulink url="http://www.pcre.org/man.txt">http://www.pcre.org/man.txt</ulink>.
2445 You might also find the Perl man page on regular expressions (<literal>man perlre</literal>)
2446 useful, which is available on-line at <ulink
2447 url="http://perldoc.perl.org/perlre.html">http://perldoc.perl.org/perlre.html</ulink>.
2451 Note that the path pattern is automatically left-anchored at the <quote>/</quote>,
2452 i.e. it matches as if it would start with a <quote>^</quote> (regular expression speak
2453 for the beginning of a line).
2457 Please also note that matching in the path is <emphasis>CASE INSENSITIVE</emphasis>
2458 by default, but you can switch to case sensitive at any point in the pattern by using the
2459 <quote>(?-i)</quote> switch: <literal>www.example.com/(?-i)PaTtErN.*</literal> will match
2460 only documents whose path starts with <literal>PaTtErN</literal> in
2461 <emphasis>exactly</emphasis> this capitalization.
2466 <term><literal>.example.com/.*</literal></term>
2469 Is equivalent to just <quote>.example.com</quote>, since any documents
2470 within that domain are matched with or without the <quote>.*</quote>
2471 regular expression. This is redundant
2476 <term><literal>.example.com/.*/index.html$</literal></term>
2479 Will match any page in the domain of <quote>example.com</quote> that is
2480 named <quote>index.html</quote>, and that is part of some path. For
2481 example, it matches <quote>www.example.com/testing/index.html</quote> but
2482 NOT <quote>www.example.com/index.html</quote> because the regular
2483 expression called for at least two <quote>/'s</quote>, thus the path
2484 requirement. It also would match
2485 <quote>www.example.com/testing/index_html</quote>, because of the
2486 special meta-character <quote>.</quote>.
2491 <term><literal>.example.com/(.*/)?index\.html$</literal></term>
2494 This regular expression is conditional so it will match any page
2495 named <quote>index.html</quote> regardless of path which in this case can
2496 have one or more <quote>/'s</quote>. And this one must contain exactly
2497 <quote>.html</quote> (but does not have to end with that!).
2502 <term><literal>.example.com/(.*/)(ads|banners?|junk)</literal></term>
2505 This regular expression will match any path of <quote>example.com</quote>
2506 that contains any of the words <quote>ads</quote>, <quote>banner</quote>,
2507 <quote>banners</quote> (because of the <quote>?</quote>) or <quote>junk</quote>.
2508 The path does not have to end in these words, just contain them.
2513 <term><literal>.example.com/(.*/)(ads|banners?|junk)/.*\.(jpe?g|gif|png)$</literal></term>
2516 This is very much the same as above, except now it must end in either
2517 <quote>.jpg</quote>, <quote>.jpeg</quote>, <quote>.gif</quote> or <quote>.png</quote>. So this
2518 one is limited to common image formats.
2525 There are many, many good examples to be found in <filename>default.action</filename>,
2526 and more tutorials below in <link linkend="regex">Appendix on regular expressions</link>.
2531 <!-- ~ End section ~ -->
2534 <!-- ~~~~~ New section ~~~~~ -->
2535 <sect3 id="tag-pattern"><title>The Tag Pattern</title>
2538 Tag patterns are used to change the applying actions based on the
2539 request's tags. Tags can be created with either the
2540 <link linkend="CLIENT-HEADER-TAGGER">client-header-tagger</link>
2541 or the <link linkend="SERVER-HEADER-TAGGER">server-header-tagger</link> action.
2545 Tag patterns have to start with <quote>TAG:</quote>, so &my-app;
2546 can tell them apart from URL patterns. Everything after the colon
2547 including white space, is interpreted as a regular expression with
2548 path pattern syntax, except that tag patterns aren't left-anchored
2549 automatically (&my-app; doesn't silently add a <quote>^</quote>,
2550 you have to do it yourself if you need it).
2554 To match all requests that are tagged with <quote>foo</quote>
2555 your pattern line should be <quote>TAG:^foo$</quote>,
2556 <quote>TAG:foo</quote> would work as well, but it would also
2557 match requests whose tags contain <quote>foo</quote> somewhere.
2558 <quote>TAG: foo</quote> wouldn't work as it requires white space.
2562 Sections can contain URL and tag patterns at the same time,
2563 but tag patterns are checked after the URL patterns and thus
2564 always overrule them, even if they are located before the URL patterns.
2568 Once a new tag is added, Privoxy checks right away if it's matched by one
2569 of the tag patterns and updates the action settings accordingly. As a result
2570 tags can be used to activate other tagger actions, as long as these other
2571 taggers look for headers that haven't already be parsed.
2575 For example you could tag client requests which use the
2576 <literal>POST</literal> method,
2577 then use this tag to activate another tagger that adds a tag if cookies
2578 are sent, and then use a block action based on the cookie tag. This allows
2579 the outcome of one action, to be input into a subsequent action. However if
2580 you'd reverse the position of the described taggers, and activated the
2581 method tagger based on the cookie tagger, no method tags would be created.
2582 The method tagger would look for the request line, but at the time
2583 the cookie tag is created, the request line has already been parsed.
2587 While this is a limitation you should be aware of, this kind of
2588 indirection is seldom needed anyway and even the example doesn't
2589 make too much sense.
2596 <!-- ~ End section ~ -->
2599 <!-- ~~~~~ New section ~~~~~ -->
2601 <sect2 id="actions">
2602 <title>Actions</title>
2604 All actions are disabled by default, until they are explicitly enabled
2605 somewhere in an actions file. Actions are turned on if preceded with a
2606 <quote>+</quote>, and turned off if preceded with a <quote>-</quote>. So a
2607 <literal>+action</literal> means <quote>do that action</quote>, e.g.
2608 <literal>+block</literal> means <quote>please block URLs that match the
2609 following patterns</quote>, and <literal>-block</literal> means <quote>don't
2610 block URLs that match the following patterns, even if <literal>+block</literal>
2611 previously applied.</quote>
2616 Again, actions are invoked by placing them on a line, enclosed in curly braces and
2617 separated by whitespace, like in
2618 <literal>{+some-action -some-other-action{some-parameter}}</literal>,
2619 followed by a list of URL patterns, one per line, to which they apply.
2620 Together, the actions line and the following pattern lines make up a section
2621 of the actions file.
2625 Actions fall into three categories:
2632 Boolean, i.e the action can only be <quote>enabled</quote> or
2633 <quote>disabled</quote>. Syntax:
2637 +<replaceable class="function">name</replaceable> # enable action <replaceable class="parameter">name</replaceable>
2638 -<replaceable class="function">name</replaceable> # disable action <replaceable class="parameter">name</replaceable></screen>
2641 Example: <literal>+handle-as-image</literal>
2648 Parameterized, where some value is required in order to enable this type of action.
2653 +<replaceable class="function">name</replaceable>{<replaceable class="parameter">param</replaceable>} # enable action and set parameter to <replaceable class="parameter">param</replaceable>,
2654 # overwriting parameter from previous match if necessary
2655 -<replaceable class="function">name</replaceable> # disable action. The parameter can be omitted</screen>
2658 Note that if the URL matches multiple positive forms of a parameterized action,
2659 the last match wins, i.e. the params from earlier matches are simply ignored.
2662 Example: <literal>+hide-user-agent{Mozilla/5.0 (X11; U; FreeBSD i386; en-US; rv:1.8.1.4) Gecko/20070602 Firefox/2.0.0.4}</literal>
2668 Multi-value. These look exactly like parameterized actions,
2669 but they behave differently: If the action applies multiple times to the
2670 same URL, but with different parameters, <emphasis>all</emphasis> the parameters
2671 from <emphasis>all</emphasis> matches are remembered. This is used for actions
2672 that can be executed for the same request repeatedly, like adding multiple
2673 headers, or filtering through multiple filters. Syntax:
2677 +<replaceable class="function">name</replaceable>{<replaceable class="parameter">param</replaceable>} # enable action and add <replaceable class="parameter">param</replaceable> to the list of parameters
2678 -<replaceable class="function">name</replaceable>{<replaceable class="parameter">param</replaceable>} # remove the parameter <replaceable class="parameter">param</replaceable> from the list of parameters
2679 # If it was the last one left, disable the action.
2680 <replaceable class="parameter">-name</replaceable> # disable this action completely and remove all parameters from the list</screen>
2683 Examples: <literal>+add-header{X-Fun-Header: Some text}</literal> and
2684 <literal>+filter{html-annoyances}</literal>
2692 If nothing is specified in any actions file, no <quote>actions</quote> are
2693 taken. So in this case <application>Privoxy</application> would just be a
2694 normal, non-blocking, non-filtering proxy. You must specifically enable the
2695 privacy and blocking features you need (although the provided default actions
2696 files will give a good starting point).
2700 Later defined action sections always over-ride earlier ones of the same type.
2701 So exceptions to any rules you make, should come in the latter part of the file (or
2702 in a file that is processed later when using multiple actions files such
2703 as <filename>user.action</filename>). For multi-valued actions, the actions
2704 are applied in the order they are specified. Actions files are processed in
2705 the order they are defined in <filename>config</filename> (the default
2706 installation has three actions files). It also quite possible for any given
2707 URL to match more than one <quote>pattern</quote> (because of wildcards and
2708 regular expressions), and thus to trigger more than one set of actions! Last
2712 <!-- start actions listing -->
2714 The list of valid <application>Privoxy</application> actions are:
2718 <!-- ********************************************************** -->
2719 <!-- Please note the below defined actions use id's that are -->
2720 <!-- probably linked from other places, so please don't change. -->
2722 <!-- ********************************************************** -->
2725 <!-- ~~~~~ New section ~~~~~ -->
2727 <sect3 renderas="sect4" id="add-header">
2728 <title>add-header</title>
2732 <term>Typical use:</term>
2734 <para>Confuse log analysis, custom applications</para>
2739 <term>Effect:</term>
2742 Sends a user defined HTTP header to the web server.
2749 <!-- boolean, parameterized, Multi-value -->
2751 <para>Multi-value.</para>
2756 <term>Parameter:</term>
2759 Any string value is possible. Validity of the defined HTTP headers is not checked.
2760 It is recommended that you use the <quote><literal>X-</literal></quote> prefix
2770 This action may be specified multiple times, in order to define multiple
2771 headers. This is rarely needed for the typical user. If you don't know what
2772 <quote>HTTP headers</quote> are, you definitely don't need to worry about this
2779 <term>Example usage:</term>
2782 <screen>+add-header{X-User-Tracking: sucks}</screen>
2790 <!-- ~~~~~ New section ~~~~~ -->
2791 <sect3 renderas="sect4" id="block">
2792 <title>block</title>
2796 <term>Typical use:</term>
2798 <para>Block ads or other unwanted content</para>
2803 <term>Effect:</term>
2806 Requests for URLs to which this action applies are blocked, i.e. the
2807 requests are trapped by &my-app; and the requested URL is never retrieved,
2808 but is answered locally with a substitute page or image, as determined by
2810 linkend="handle-as-image">handle-as-image</link></literal>,
2812 linkend="set-image-blocker">set-image-blocker</link></literal>, and
2814 linkend="handle-as-empty-document">handle-as-empty-document</link></literal> actions.
2822 <!-- boolean, parameterized, Multi-value -->
2824 <para>Parameterized.</para>
2829 <term>Parameter:</term>
2831 <para>A block reason that should be given to the user.</para>
2839 <application>Privoxy</application> sends a special <quote>BLOCKED</quote> page
2840 for requests to blocked pages. This page contains the block reason given as
2841 parameter, a link to find out why the block action applies, and a click-through
2842 to the blocked content (the latter only if the force feature is available and
2846 This doesn't actually work in all browser configuration and the user probably doesn't care anyway.
2848 The <quote>BLOCKED</quote> page adapts to the available
2849 screen space -- it displays full-blown if space allows, or miniaturized and text-only
2850 if loaded into a small frame or window. If you are using <application>Privoxy</application>
2851 right now, you can take a look at the
2852 <ulink url="http://ads.bannerserver.example.com/nasty-ads/sponsor.html"><quote>BLOCKED</quote>
2857 A very important exception occurs if <emphasis>both</emphasis>
2858 <literal>block</literal> and <literal><link linkend="handle-as-image">handle-as-image</link></literal>,
2859 apply to the same request: it will then be replaced by an image. If
2860 <literal><link linkend="set-image-blocker">set-image-blocker</link></literal>
2861 (see below) also applies, the type of image will be determined by its parameter,
2862 if not, the standard checkerboard pattern is sent.
2865 It is important to understand this process, in order
2866 to understand how <application>Privoxy</application> deals with
2867 ads and other unwanted content. Blocking is a core feature, and one
2868 upon which various other features depend.
2871 The <literal><link linkend="filter">filter</link></literal>
2872 action can perform a very similar task, by <quote>blocking</quote>
2873 banner images and other content through rewriting the relevant URLs in the
2874 document's HTML source, so they don't get requested in the first place.
2875 Note that this is a totally different technique, and it's easy to confuse the two.
2881 <term>Example usage (section):</term>
2884 <screen>{+block{No nasty stuff for you.}}
2885 # Block and replace with "blocked" page
2886 .nasty-stuff.example.com
2888 {+block{Doubleclick banners.} +handle-as-image}
2889 # Block and replace with image
2893 {+block{Layered ads.} +handle-as-empty-document}
2894 # Block and then ignore
2895 adserver.example.net/.*\.js$</screen>
2905 <!-- ~~~~~ New section ~~~~~ -->
2906 <sect3 renderas="sect4" id="client-header-filter">
2907 <title>client-header-filter</title>
2911 <term>Typical use:</term>
2914 Rewrite or remove single client headers.
2920 <term>Effect:</term>
2923 All client headers to which this action applies are filtered on-the-fly through
2924 the specified regular expression based substitutions.
2931 <!-- boolean, parameterized, Multi-value -->
2933 <para>Parameterized.</para>
2938 <term>Parameter:</term>
2941 The name of a client-header filter, as defined in one of the
2942 <link linkend="filter-file">filter files</link>.
2951 Client-header filters are applied to each header on its own, not to
2952 all at once. This makes it easier to diagnose problems, but on the downside
2953 you can't write filters that only change header x if header y's value is z.
2954 You can do that by using tags though.
2957 Client-header filters are executed after the other header actions have finished
2958 and use their output as input.
2961 If the request URL gets changed, &my-app; will detect that and use the new
2962 one. This can be used to rewrite the request destination behind the client's
2963 back, for example to specify a Tor exit relay for certain requests.
2966 Please refer to the <link linkend="filter-file">filter file chapter</link>
2967 to learn which client-header filters are available by default, and how to
2975 <term>Example usage (section):</term>
2979 # Hide Tor exit notation in Host and Referer Headers
2980 {+client-header-filter{hide-tor-exit-notation}}
2991 <!-- ~~~~~ New section ~~~~~ -->
2992 <sect3 renderas="sect4" id="client-header-tagger">
2993 <title>client-header-tagger</title>
2997 <term>Typical use:</term>
3000 Block requests based on their headers.
3006 <term>Effect:</term>
3009 Client headers to which this action applies are filtered on-the-fly through
3010 the specified regular expression based substitutions, the result is used as
3018 <!-- boolean, parameterized, Multi-value -->
3020 <para>Parameterized.</para>
3025 <term>Parameter:</term>
3028 The name of a client-header tagger, as defined in one of the
3029 <link linkend="filter-file">filter files</link>.
3038 Client-header taggers are applied to each header on its own,
3039 and as the header isn't modified, each tagger <quote>sees</quote>
3043 Client-header taggers are the first actions that are executed
3044 and their tags can be used to control every other action.
3050 <term>Example usage (section):</term>
3054 # Tag every request with the User-Agent header
3055 {+client-header-tagger{user-agent}}
3066 <!-- ~~~~~ New section ~~~~~ -->
3067 <sect3 renderas="sect4" id="content-type-overwrite">
3068 <title>content-type-overwrite</title>
3072 <term>Typical use:</term>
3074 <para>Stop useless download menus from popping up, or change the browser's rendering mode</para>
3079 <term>Effect:</term>
3082 Replaces the <quote>Content-Type:</quote> HTTP server header.
3089 <!-- Boolean, Parameterized, Multi-value -->
3091 <para>Parameterized.</para>
3096 <term>Parameter:</term>
3108 The <quote>Content-Type:</quote> HTTP server header is used by the
3109 browser to decide what to do with the document. The value of this
3110 header can cause the browser to open a download menu instead of
3111 displaying the document by itself, even if the document's format is
3112 supported by the browser.
3115 The declared content type can also affect which rendering mode
3116 the browser chooses. If XHTML is delivered as <quote>text/html</quote>,
3117 many browsers treat it as yet another broken HTML document.
3118 If it is send as <quote>application/xml</quote>, browsers with
3119 XHTML support will only display it, if the syntax is correct.
3122 If you see a web site that proudly uses XHTML buttons, but sets
3123 <quote>Content-Type: text/html</quote>, you can use &my-app;
3124 to overwrite it with <quote>application/xml</quote> and validate
3125 the web master's claim inside your XHTML-supporting browser.
3126 If the syntax is incorrect, the browser will complain loudly.
3129 You can also go the opposite direction: if your browser prints
3130 error messages instead of rendering a document falsely declared
3131 as XHTML, you can overwrite the content type with
3132 <quote>text/html</quote> and have it rendered as broken HTML document.
3135 By default <literal>content-type-overwrite</literal> only replaces
3136 <quote>Content-Type:</quote> headers that look like some kind of text.
3137 If you want to overwrite it unconditionally, you have to combine it with
3138 <literal><link linkend="force-text-mode">force-text-mode</link></literal>.
3139 This limitation exists for a reason, think twice before circumventing it.
3142 Most of the time it's easier to replace this action with a custom
3143 <literal><link linkend="server-header-filter">server-header filter</link></literal>.
3144 It allows you to activate it for every document of a certain site and it will still
3145 only replace the content types you aimed at.
3148 Of course you can apply <literal>content-type-overwrite</literal>
3149 to a whole site and then make URL based exceptions, but it's a lot
3150 more work to get the same precision.
3156 <term>Example usage (sections):</term>
3159 <screen># Check if www.example.net/ really uses valid XHTML
3160 { +content-type-overwrite{application/xml} }
3163 # but leave the content type unmodified if the URL looks like a style sheet
3164 {-content-type-overwrite}
3165 www.example.net/.*\.css$
3166 www.example.net/.*style
3175 <!-- ~~~~~ New section ~~~~~ -->
3176 <sect3 renderas="sect4" id="crunch-client-header">
3180 <title>crunch-client-header</title>
3184 <term>Typical use:</term>
3186 <para>Remove a client header <application>Privoxy</application> has no dedicated action for.</para>
3191 <term>Effect:</term>
3194 Deletes every header sent by the client that contains the string the user supplied as parameter.
3201 <!-- Boolean, Parameterized, Multi-value -->
3203 <para>Parameterized.</para>
3208 <term>Parameter:</term>
3220 This action allows you to block client headers for which no dedicated
3221 <application>Privoxy</application> action exists.
3222 <application>Privoxy</application> will remove every client header that
3223 contains the string you supplied as parameter.
3226 Regular expressions are <emphasis>not supported</emphasis> and you can't
3227 use this action to block different headers in the same request, unless
3228 they contain the same string.
3231 <literal>crunch-client-header</literal> is only meant for quick tests.
3232 If you have to block several different headers, or only want to modify
3233 parts of them, you should use a
3234 <literal><link linkend="client-header-filter">client-header filter</link></literal>.
3238 Don't block any header without understanding the consequences.
3245 <term>Example usage (section):</term>
3248 <screen># Block the non-existent "Privacy-Violation:" client header
3249 { +crunch-client-header{Privacy-Violation:} }
3259 <!-- ~~~~~ New section ~~~~~ -->
3260 <sect3 renderas="sect4" id="crunch-if-none-match">
3261 <title>crunch-if-none-match</title>
3267 <term>Typical use:</term>
3269 <para>Prevent yet another way to track the user's steps between sessions.</para>
3274 <term>Effect:</term>
3277 Deletes the <quote>If-None-Match:</quote> HTTP client header.
3284 <!-- Boolean, Parameterized, Multi-value -->
3286 <para>Boolean.</para>
3291 <term>Parameter:</term>
3303 Removing the <quote>If-None-Match:</quote> HTTP client header
3304 is useful for filter testing, where you want to force a real
3305 reload instead of getting status code <quote>304</quote> which
3306 would cause the browser to use a cached copy of the page.
3309 It is also useful to make sure the header isn't used as a cookie
3310 replacement (unlikely but possible).
3313 Blocking the <quote>If-None-Match:</quote> header shouldn't cause any
3314 caching problems, as long as the <quote>If-Modified-Since:</quote> header
3315 isn't blocked or missing as well.
3318 It is recommended to use this action together with
3319 <literal><link linkend="hide-if-modified-since">hide-if-modified-since</link></literal>
3321 <literal><link linkend="overwrite-last-modified">overwrite-last-modified</link></literal>.
3327 <term>Example usage (section):</term>
3330 <screen># Let the browser revalidate cached documents but don't
3331 # allow the server to use the revalidation headers for user tracking.
3332 {+hide-if-modified-since{-60} \
3333 +overwrite-last-modified{randomize} \
3334 +crunch-if-none-match}
3343 <!-- ~~~~~ New section ~~~~~ -->
3344 <sect3 renderas="sect4" id="crunch-incoming-cookies">
3345 <title>crunch-incoming-cookies</title>
3349 <term>Typical use:</term>
3352 Prevent the web server from setting HTTP cookies on your system
3358 <term>Effect:</term>
3361 Deletes any <quote>Set-Cookie:</quote> HTTP headers from server replies.
3368 <!-- Boolean, Parameterized, Multi-value -->
3370 <para>Boolean.</para>
3375 <term>Parameter:</term>
3387 This action is only concerned with <emphasis>incoming</emphasis> HTTP cookies. For
3388 <emphasis>outgoing</emphasis> HTTP cookies, use
3389 <literal><link linkend="crunch-outgoing-cookies">crunch-outgoing-cookies</link></literal>.
3390 Use <emphasis>both</emphasis> to disable HTTP cookies completely.
3393 It makes <emphasis>no sense at all</emphasis> to use this action in conjunction
3394 with the <literal><link linkend="session-cookies-only">session-cookies-only</link></literal> action,
3395 since it would prevent the session cookies from being set. See also
3396 <literal><link linkend="filter-content-cookies">filter-content-cookies</link></literal>.
3402 <term>Example usage:</term>
3405 <screen>+crunch-incoming-cookies</screen>
3413 <!-- ~~~~~ New section ~~~~~ -->
3414 <sect3 renderas="sect4" id="crunch-server-header">
3415 <title>crunch-server-header</title>
3421 <term>Typical use:</term>
3423 <para>Remove a server header <application>Privoxy</application> has no dedicated action for.</para>
3428 <term>Effect:</term>
3431 Deletes every header sent by the server that contains the string the user supplied as parameter.
3438 <!-- Boolean, Parameterized, Multi-value -->
3440 <para>Parameterized.</para>
3445 <term>Parameter:</term>
3457 This action allows you to block server headers for which no dedicated
3458 <application>Privoxy</application> action exists. <application>Privoxy</application>
3459 will remove every server header that contains the string you supplied as parameter.
3462 Regular expressions are <emphasis>not supported</emphasis> and you can't
3463 use this action to block different headers in the same request, unless
3464 they contain the same string.
3467 <literal>crunch-server-header</literal> is only meant for quick tests.
3468 If you have to block several different headers, or only want to modify
3469 parts of them, you should use a custom
3470 <literal><link linkend="server-header-filter">server-header filter</link></literal>.
3474 Don't block any header without understanding the consequences.
3481 <term>Example usage (section):</term>
3484 <screen># Crunch server headers that try to prevent caching
3485 { +crunch-server-header{no-cache} }
3494 <!-- ~~~~~ New section ~~~~~ -->
3495 <sect3 renderas="sect4" id="crunch-outgoing-cookies">
3496 <title>crunch-outgoing-cookies</title>
3500 <term>Typical use:</term>
3503 Prevent the web server from reading any HTTP cookies from your system
3509 <term>Effect:</term>
3512 Deletes any <quote>Cookie:</quote> HTTP headers from client requests.
3519 <!-- Boolean, Parameterized, Multi-value -->
3521 <para>Boolean.</para>
3526 <term>Parameter:</term>
3538 This action is only concerned with <emphasis>outgoing</emphasis> HTTP cookies. For
3539 <emphasis>incoming</emphasis> HTTP cookies, use
3540 <literal><link linkend="crunch-incoming-cookies">crunch-incoming-cookies</link></literal>.
3541 Use <emphasis>both</emphasis> to disable HTTP cookies completely.
3544 It makes <emphasis>no sense at all</emphasis> to use this action in conjunction
3545 with the <literal><link linkend="session-cookies-only">session-cookies-only</link></literal> action,
3546 since it would prevent the session cookies from being read.
3552 <term>Example usage:</term>
3555 <screen>+crunch-outgoing-cookies</screen>
3564 <!-- ~~~~~ New section ~~~~~ -->
3565 <sect3 renderas="sect4" id="deanimate-gifs">
3566 <title>deanimate-gifs</title>
3570 <term>Typical use:</term>
3572 <para>Stop those annoying, distracting animated GIF images.</para>
3577 <term>Effect:</term>
3580 De-animate GIF animations, i.e. reduce them to their first or last image.
3587 <!-- boolean, parameterized, Multi-value -->
3589 <para>Parameterized.</para>
3594 <term>Parameter:</term>
3597 <quote>last</quote> or <quote>first</quote>
3606 This will also shrink the images considerably (in bytes, not pixels!). If
3607 the option <quote>first</quote> is given, the first frame of the animation
3608 is used as the replacement. If <quote>last</quote> is given, the last
3609 frame of the animation is used instead, which probably makes more sense for
3610 most banner animations, but also has the risk of not showing the entire
3611 last frame (if it is only a delta to an earlier frame).
3614 You can safely use this action with patterns that will also match non-GIF
3615 objects, because no attempt will be made at anything that doesn't look like
3622 <term>Example usage:</term>
3625 <screen>+deanimate-gifs{last}</screen>
3632 <!-- ~~~~~ New section ~~~~~ -->
3633 <sect3 renderas="sect4" id="downgrade-http-version">
3634 <title>downgrade-http-version</title>
3638 <term>Typical use:</term>
3640 <para>Work around (very rare) problems with HTTP/1.1</para>
3645 <term>Effect:</term>
3648 Downgrades HTTP/1.1 client requests and server replies to HTTP/1.0.
3655 <!-- boolean, parameterized, Multi-value -->
3657 <para>Boolean.</para>
3662 <term>Parameter:</term>
3674 This is a left-over from the time when <application>Privoxy</application>
3675 didn't support important HTTP/1.1 features well. It is left here for the
3676 unlikely case that you experience HTTP/1.1 related problems with some server
3677 out there. Not all HTTP/1.1 features and requirements are supported yet,
3678 so there is a chance you might need this action.
3684 <term>Example usage (section):</term>
3687 <screen>{+downgrade-http-version}
3688 problem-host.example.com</screen>
3696 <!-- ~~~~~ New section ~~~~~ -->
3697 <sect3 renderas="sect4" id="fast-redirects">
3698 <title>fast-redirects</title>
3702 <term>Typical use:</term>
3704 <para>Fool some click-tracking scripts and speed up indirect links.</para>
3709 <term>Effect:</term>
3712 Detects redirection URLs and redirects the browser without contacting
3713 the redirection server first.
3720 <!-- boolean, parameterized, Multi-value -->
3722 <para>Parameterized.</para>
3727 <term>Parameter:</term>
3732 <quote>simple-check</quote> to just search for the string <quote>http://</quote>
3733 to detect redirection URLs.
3738 <quote>check-decoded-url</quote> to decode URLs (if necessary) before searching
3739 for redirection URLs.
3750 Many sites, like yahoo.com, don't just link to other sites. Instead, they
3751 will link to some script on their own servers, giving the destination as a
3752 parameter, which will then redirect you to the final target. URLs
3753 resulting from this scheme typically look like:
3754 <quote>http://www.example.org/click-tracker.cgi?target=http%3a//www.example.net/</quote>.
3757 Sometimes, there are even multiple consecutive redirects encoded in the
3758 URL. These redirections via scripts make your web browsing more traceable,
3759 since the server from which you follow such a link can see where you go
3760 to. Apart from that, valuable bandwidth and time is wasted, while your
3761 browser asks the server for one redirect after the other. Plus, it feeds
3765 This feature is currently not very smart and is scheduled for improvement.
3766 If it is enabled by default, you will have to create some exceptions to
3767 this action. It can lead to failures in several ways:
3770 Not every URLs with other URLs as parameters is evil.
3771 Some sites offer a real service that requires this information to work.
3772 For example a validation service needs to know, which document to validate.
3773 <literal>fast-redirects</literal> assumes that every URL parameter that
3774 looks like another URL is a redirection target, and will always redirect to
3775 the last one. Most of the time the assumption is correct, but if it isn't,
3776 the user gets redirected anyway.
3779 Another failure occurs if the URL contains other parameters after the URL parameter.
3781 <quote>http://www.example.org/?redirect=http%3a//www.example.net/&foo=bar</quote>.
3782 contains the redirection URL <quote>http://www.example.net/</quote>,
3783 followed by another parameter. <literal>fast-redirects</literal> doesn't know that
3784 and will cause a redirect to <quote>http://www.example.net/&foo=bar</quote>.
3785 Depending on the target server configuration, the parameter will be silently ignored
3786 or lead to a <quote>page not found</quote> error. You can prevent this problem by
3787 first using the <literal><link linkend="redirect">redirect</link></literal> action
3788 to remove the last part of the URL, but it requires a little effort.
3791 To detect a redirection URL, <literal>fast-redirects</literal> only
3792 looks for the string <quote>http://</quote>, either in plain text
3793 (invalid but often used) or encoded as <quote>http%3a//</quote>.
3794 Some sites use their own URL encoding scheme, encrypt the address
3795 of the target server or replace it with a database id. In theses cases
3796 <literal>fast-redirects</literal> is fooled and the request reaches the
3797 redirection server where it probably gets logged.
3803 <term>Example usage:</term>
3807 { +fast-redirects{simple-check} }
3810 { +fast-redirects{check-decoded-url} }
3811 another.example.com/testing</screen>
3820 <!-- ~~~~~ New section ~~~~~ -->
3821 <sect3 renderas="sect4" id="filter">
3822 <title>filter</title>
3826 <term>Typical use:</term>
3828 <para>Get rid of HTML and JavaScript annoyances, banner advertisements (by size),
3829 do fun text replacements, add personalized effects, etc.</para>
3834 <term>Effect:</term>
3837 All instances of text-based type, most notably HTML and JavaScript, to which
3838 this action applies, can be filtered on-the-fly through the specified regular
3839 expression based substitutions. (Note: as of version 3.0.3 plain text documents
3840 are exempted from filtering, because web servers often use the
3841 <literal>text/plain</literal> MIME type for all files whose type they don't know.)
3848 <!-- boolean, parameterized, Multi-value -->
3850 <para>Parameterized.</para>
3855 <term>Parameter:</term>
3858 The name of a content filter, as defined in the <link linkend="filter-file">filter file</link>.
3859 Filters can be defined in one or more files as defined by the
3860 <literal><link linkend="filterfile">filterfile</link></literal>
3861 option in the <link linkend="config">config file</link>.
3862 <filename>default.filter</filename> is the collection of filters
3863 supplied by the developers. Locally defined filters should go
3864 in their own file, such as <filename>user.filter</filename>.
3867 When used in its negative form,
3868 and without parameters, <emphasis>all</emphasis> filtering is completely disabled.
3877 For your convenience, there are a number of pre-defined filters available
3878 in the distribution filter file that you can use. See the examples below for
3882 Filtering requires buffering the page content, which may appear to
3883 slow down page rendering since nothing is displayed until all content has
3884 passed the filters. (It does not really take longer, but seems that way
3885 since the page is not incrementally displayed.) This effect will be more
3886 noticeable on slower connections.
3889 <quote>Rolling your own</quote>
3890 filters requires a knowledge of
3891 <ulink url="http://en.wikipedia.org/wiki/Regular_expressions"><quote>Regular
3892 Expressions</quote></ulink> and
3893 <ulink url="http://en.wikipedia.org/wiki/Html"><quote>HTML</quote></ulink>.
3894 This is very powerful feature, and potentially very intrusive.
3895 Filters should be used with caution, and where an equivalent
3896 <quote>action</quote> is not available.
3899 The amount of data that can be filtered is limited to the
3900 <literal><link linkend="buffer-limit">buffer-limit</link></literal>
3901 option in the main <link linkend="config">config file</link>. The
3902 default is 4096 KB (4 Megs). Once this limit is exceeded, the buffered
3903 data, and all pending data, is passed through unfiltered.
3906 Inappropriate MIME types, such as zipped files, are not filtered at all.
3907 (Again, only text-based types except plain text). Encrypted SSL data
3908 (from HTTPS servers) cannot be filtered either, since this would violate
3909 the integrity of the secure transaction. In some situations it might
3910 be necessary to protect certain text, like source code, from filtering
3911 by defining appropriate <literal>-filter</literal> exceptions.
3914 Compressed content can't be filtered either, unless &my-app;
3915 is compiled with zlib support (requires at least &my-app; 3.0.7),
3916 in which case &my-app; will decompress the content before filtering
3920 If you use a &my-app; version without zlib support, but want filtering to work on
3921 as much documents as possible, even those that would normally be sent compressed,
3922 you must use the <literal><link linkend="prevent-compression">prevent-compression</link></literal>
3923 action in conjunction with <literal>filter</literal>.
3926 Content filtering can achieve some of the same effects as the
3927 <literal><link linkend="block">block</link></literal>
3928 action, i.e. it can be used to block ads and banners. But the mechanism
3929 works quite differently. One effective use, is to block ad banners
3930 based on their size (see below), since many of these seem to be somewhat
3934 <link linkend="contact">Feedback</link> with suggestions for new or
3935 improved filters is particularly welcome!
3938 The below list has only the names and a one-line description of each
3939 predefined filter. There are <link linkend="predefined-filters">more
3940 verbose explanations</link> of what these filters do in the <link
3941 linkend="filter-file">filter file chapter</link>.
3947 <term>Example usage (with filters from the distribution <filename>default.filter</filename> file).
3948 See <link linkend="PREDEFINED-FILTERS">the Predefined Filters section</link> for
3949 more explanation on each:</term>
3952 <anchor id="filter-js-annoyances">
3953 <screen>+filter{js-annoyances} # Get rid of particularly annoying JavaScript abuse</screen>
3956 <anchor id="filter-js-events">
3957 <screen>+filter{js-events} # Kill all JS event bindings (Radically destructive! Only for extra nasty sites)</screen>
3960 <anchor id="filter-html-annoyances">
3961 <screen>+filter{html-annoyances} # Get rid of particularly annoying HTML abuse</screen>
3964 <anchor id="filter-content-cookies">
3965 <screen>+filter{content-cookies} # Kill cookies that come in the HTML or JS content</screen>
3968 <anchor id="filter-refresh-tags">
3969 <screen>+filter{refresh-tags} # Kill automatic refresh tags (for dial-on-demand setups)</screen>
3972 <anchor id="filter-unsolicited-popups">
3973 <screen>+filter{unsolicited-popups} # Disable only unsolicited pop-up windows. Useful if your browser lacks this ability.</screen>
3976 <anchor id="filter-all-popups">
3977 <screen>+filter{all-popups} # Kill all popups in JavaScript and HTML. Useful if your browser lacks this ability.</screen>
3980 <anchor id="filter-img-reorder">
3981 <screen>+filter{img-reorder} # Reorder attributes in <img> tags to make the banners-by-* filters more effective</screen>
3984 <anchor id="filter-banners-by-size">
3985 <screen>+filter{banners-by-size} # Kill banners by size</screen>
3988 <anchor id="filter-banners-by-link">
3989 <screen>+filter{banners-by-link} # Kill banners by their links to known clicktrackers</screen>
3992 <anchor id="filter-webbugs">
3993 <screen>+filter{webbugs} # Squish WebBugs (1x1 invisible GIFs used for user tracking)</screen>
3996 <anchor id="filter-tiny-textforms">
3997 <screen>+filter{tiny-textforms} # Extend those tiny textareas up to 40x80 and kill the hard wrap</screen>
4000 <anchor id="filter-jumping-windows">
4001 <screen>+filter{jumping-windows} # Prevent windows from resizing and moving themselves</screen>
4004 <anchor id="filter-frameset-borders">
4005 <screen>+filter{frameset-borders} # Give frames a border and make them resizeable</screen>
4008 <anchor id="filter-demoronizer">
4009 <screen>+filter{demoronizer} # Fix MS's non-standard use of standard charsets</screen>
4012 <anchor id="filter-shockwave-flash">
4013 <screen>+filter{shockwave-flash} # Kill embedded Shockwave Flash objects</screen>
4016 <anchor id="filter-quicktime-kioskmode">
4017 <screen>+filter{quicktime-kioskmode} # Make Quicktime movies savable</screen>
4020 <anchor id="filter-fun">
4021 <screen>+filter{fun} # Text replacements for subversive browsing fun!</screen>
4024 <anchor id="filter-crude-parental">
4025 <screen>+filter{crude-parental} # Crude parental filtering (demo only)</screen>
4028 <anchor id="filter-ie-exploits">
4029 <screen>+filter{ie-exploits} # Disable a known Internet Explorer bug exploits</screen>
4032 <anchor id="filter-site-specifics">
4033 <screen>+filter{site-specifics} # Custom filters for specific site related problems</screen>
4036 <anchor id="filter-google">
4037 <screen>+filter{google} # Removes text ads and other Google specific improvements</screen>
4040 <anchor id="filter-yahoo">
4041 <screen>+filter{yahoo} # Removes text ads and other Yahoo specific improvements</screen>
4044 <anchor id="filter-msn">
4045 <screen>+filter{msn} # Removes text ads and other MSN specific improvements</screen>
4048 <anchor id="filter-blogspot">
4049 <screen>+filter{blogspot} # Cleans up Blogspot blogs</screen>
4052 <anchor id="filter-no-ping">
4053 <screen>+filter{no-ping} # Removes non-standard ping attributes from anchor and area tags</screen>
4061 <!-- ~~~~~ New section ~~~~~ -->
4062 <sect3 renderas="sect4" id="force-text-mode">
4063 <title>force-text-mode</title>
4069 <term>Typical use:</term>
4071 <para>Force <application>Privoxy</application> to treat a document as if it was in some kind of <emphasis>text</emphasis> format. </para>
4076 <term>Effect:</term>
4079 Declares a document as text, even if the <quote>Content-Type:</quote> isn't detected as such.
4086 <!-- Boolean, Parameterized, Multi-value -->
4088 <para>Boolean.</para>
4093 <term>Parameter:</term>
4105 As explained <literal><link linkend="filter">above</link></literal>,
4106 <application>Privoxy</application> tries to only filter files that are
4107 in some kind of text format. The same restrictions apply to
4108 <literal><link linkend="content-type-overwrite">content-type-overwrite</link></literal>.
4109 <literal>force-text-mode</literal> declares a document as text,
4110 without looking at the <quote>Content-Type:</quote> first.
4114 Think twice before activating this action. Filtering binary data
4115 with regular expressions can cause file damage.
4122 <term>Example usage:</term>
4135 <!-- ~~~~~ New section ~~~~~ -->
4136 <sect3 renderas="sect4" id="forward-override">
4137 <title>forward-override</title>
4143 <term>Typical use:</term>
4145 <para>Change the forwarding settings based on User-Agent or request origin</para>
4150 <term>Effect:</term>
4153 Overrules the forward directives in the configuration file.
4160 <!-- Boolean, Parameterized, Multi-value -->
4162 <para>Multi-value.</para>
4167 <term>Parameter:</term>
4171 <para><quote>forward .</quote> to use a direct connection without any additional proxies.</para>
4175 <quote>forward 127.0.0.1:8123</quote> to use the HTTP proxy listening at 127.0.0.1 port 8123.
4180 <quote>forward-socks4a 127.0.0.1:9050 .</quote> to use the socks4a proxy listening at
4181 127.0.0.1 port 9050. Replace <quote>forward-socks4a</quote> with <quote>forward-socks4</quote>
4182 to use a socks4 connection (with local DNS resolution) instead, use <quote>forward-socks5</quote>
4183 for socks5 connections (with remote DNS resolution).
4188 <quote>forward-socks4a 127.0.0.1:9050 proxy.example.org:8000</quote> to use the socks4a proxy
4189 listening at 127.0.0.1 port 9050 to reach the HTTP proxy listening at proxy.example.org port 8000.
4190 Replace <quote>forward-socks4a</quote> with <quote>forward-socks4</quote> to use a socks4 connection
4191 (with local DNS resolution) instead, use <quote>forward-socks5</quote>
4192 for socks5 connections (with remote DNS resolution).
4203 This action takes parameters similar to the
4204 <link linkend="forwarding">forward</link> directives in the configuration
4205 file, but without the URL pattern. It can be used as replacement, but normally it's only
4206 used in cases where matching based on the request URL isn't sufficient.
4210 Please read the description for the <link linkend="forwarding">forward</link> directives before
4211 using this action. Forwarding to the wrong people will reduce your privacy and increase the
4212 chances of man-in-the-middle attacks.
4215 If the ports are missing or invalid, default values will be used. This might change
4216 in the future and you shouldn't rely on it. Otherwise incorrect syntax causes Privoxy
4220 Use the <ulink url="http://config.privoxy.org/show-url-info">show-url-info CGI page</ulink>
4221 to verify that your forward settings do what you thought the do.
4228 <term>Example usage:</term>
4232 # Always use direct connections for requests previously tagged as
4233 # <quote>User-Agent: fetch libfetch/2.0</quote> and make sure
4234 # resuming downloads continues to work.
4235 # This way you can continue to use Tor for your normal browsing,
4236 # without overloading the Tor network with your FreeBSD ports updates
4237 # or downloads of bigger files like ISOs.
4238 # Note that HTTP headers are easy to fake and therefore their
4239 # values are as (un)trustworthy as your clients and users.
4240 {+forward-override{forward .} \
4241 -hide-if-modified-since \
4242 -overwrite-last-modified \
4244 TAG:^User-Agent: fetch libfetch/2\.0$
4253 <!-- ~~~~~ New section ~~~~~ -->
4254 <sect3 renderas="sect4" id="handle-as-empty-document">
4255 <title>handle-as-empty-document</title>
4261 <term>Typical use:</term>
4263 <para>Mark URLs that should be replaced by empty documents <emphasis>if they get blocked</emphasis></para>
4268 <term>Effect:</term>
4271 This action alone doesn't do anything noticeable. It just marks URLs.
4272 If the <literal><link linkend="block">block</link></literal> action <emphasis>also applies</emphasis>,
4273 the presence or absence of this mark decides whether an HTML <quote>BLOCKED</quote>
4274 page, or an empty document will be sent to the client as a substitute for the blocked content.
4275 The <emphasis>empty</emphasis> document isn't literally empty, but actually contains a single space.
4282 <!-- Boolean, Parameterized, Multi-value -->
4284 <para>Boolean.</para>
4289 <term>Parameter:</term>
4301 Some browsers complain about syntax errors if JavaScript documents
4302 are blocked with <application>Privoxy's</application>
4303 default HTML page; this option can be used to silence them.
4304 And of course this action can also be used to eliminate the &my-app;
4305 BLOCKED message in frames.
4308 The content type for the empty document can be specified with
4309 <literal><link linkend="content-type-overwrite">content-type-overwrite{}</link></literal>,
4310 but usually this isn't necessary.
4316 <term>Example usage:</term>
4319 <screen># Block all documents on example.org that end with ".js",
4320 # but send an empty document instead of the usual HTML message.
4321 {+block{Blocked JavaScript} +handle-as-empty-document}
4331 <!-- ~~~~~ New section ~~~~~ -->
4332 <sect3 renderas="sect4" id="handle-as-image">
4333 <title>handle-as-image</title>
4337 <term>Typical use:</term>
4339 <para>Mark URLs as belonging to images (so they'll be replaced by images <emphasis>if they do get blocked</emphasis>, rather than HTML pages)</para>
4344 <term>Effect:</term>
4347 This action alone doesn't do anything noticeable. It just marks URLs as images.
4348 If the <literal><link linkend="block">block</link></literal> action <emphasis>also applies</emphasis>,
4349 the presence or absence of this mark decides whether an HTML <quote>blocked</quote>
4350 page, or a replacement image (as determined by the <literal><link
4351 linkend="set-image-blocker">set-image-blocker</link></literal> action) will be sent to the
4352 client as a substitute for the blocked content.
4359 <!-- Boolean, Parameterized, Multi-value -->
4361 <para>Boolean.</para>
4366 <term>Parameter:</term>
4378 The below generic example section is actually part of <filename>default.action</filename>.
4379 It marks all URLs with well-known image file name extensions as images and should
4383 Users will probably only want to use the handle-as-image action in conjunction with
4384 <literal><link linkend="block">block</link></literal>, to block sources of banners, whose URLs don't
4385 reflect the file type, like in the second example section.
4388 Note that you cannot treat HTML pages as images in most cases. For instance, (in-line) ad
4389 frames require an HTML page to be sent, or they won't display properly.
4390 Forcing <literal>handle-as-image</literal> in this situation will not replace the
4391 ad frame with an image, but lead to error messages.
4397 <term>Example usage (sections):</term>
4400 <screen># Generic image extensions:
4403 /.*\.(gif|jpg|jpeg|png|bmp|ico)$
4405 # These don't look like images, but they're banners and should be
4406 # blocked as images:
4408 {+block{Nasty banners.} +handle-as-image}
4409 nasty-banner-server.example.com/junk.cgi\?output=trash
4418 <!-- ~~~~~ New section ~~~~~ -->
4419 <sect3 renderas="sect4" id="hide-accept-language">
4420 <title>hide-accept-language</title>
4426 <term>Typical use:</term>
4428 <para>Pretend to use different language settings.</para>
4433 <term>Effect:</term>
4436 Deletes or replaces the <quote>Accept-Language:</quote> HTTP header in client requests.
4443 <!-- Boolean, Parameterized, Multi-value -->
4445 <para>Parameterized.</para>
4450 <term>Parameter:</term>
4453 Keyword: <quote>block</quote>, or any user defined value.
4462 Faking the browser's language settings can be useful to make a
4463 foreign User-Agent set with
4464 <literal><link linkend="hide-user-agent">hide-user-agent</link></literal>
4468 However some sites with content in different languages check the
4469 <quote>Accept-Language:</quote> to decide which one to take by default.
4470 Sometimes it isn't possible to later switch to another language without
4471 changing the <quote>Accept-Language:</quote> header first.
4474 Therefore it's a good idea to either only change the
4475 <quote>Accept-Language:</quote> header to languages you understand,
4476 or to languages that aren't wide spread.
4479 Before setting the <quote>Accept-Language:</quote> header
4480 to a rare language, you should consider that it helps to
4481 make your requests unique and thus easier to trace.
4482 If you don't plan to change this header frequently,
4483 you should stick to a common language.
4489 <term>Example usage (section):</term>
4492 <screen># Pretend to use Canadian language settings.
4493 {+hide-accept-language{en-ca} \
4494 +hide-user-agent{Mozilla/5.0 (X11; U; OpenBSD i386; en-CA; rv:1.8.0.4) Gecko/20060628 Firefox/1.5.0.4} \
4504 <!-- ~~~~~ New section ~~~~~ -->
4505 <sect3 renderas="sect4" id="hide-content-disposition">
4506 <title>hide-content-disposition</title>
4512 <term>Typical use:</term>
4514 <para>Prevent download menus for content you prefer to view inside the browser.</para>
4519 <term>Effect:</term>
4522 Deletes or replaces the <quote>Content-Disposition:</quote> HTTP header set by some servers.
4529 <!-- Boolean, Parameterized, Multi-value -->
4531 <para>Parameterized.</para>
4536 <term>Parameter:</term>
4539 Keyword: <quote>block</quote>, or any user defined value.
4548 Some servers set the <quote>Content-Disposition:</quote> HTTP header for
4549 documents they assume you want to save locally before viewing them.
4550 The <quote>Content-Disposition:</quote> header contains the file name
4551 the browser is supposed to use by default.
4554 In most browsers that understand this header, it makes it impossible to
4555 <emphasis>just view</emphasis> the document, without downloading it first,
4556 even if it's just a simple text file or an image.
4559 Removing the <quote>Content-Disposition:</quote> header helps
4560 to prevent this annoyance, but some browsers additionally check the
4561 <quote>Content-Type:</quote> header, before they decide if they can
4562 display a document without saving it first. In these cases, you have
4563 to change this header as well, before the browser stops displaying
4567 It is also possible to change the server's file name suggestion
4568 to another one, but in most cases it isn't worth the time to set
4572 This action will probably be removed in the future,
4573 use server-header filters instead.
4579 <term>Example usage:</term>
4582 <screen># Disarm the download link in Sourceforge's patch tracker
4584 +content-type-overwrite{text/plain}\
4585 +hide-content-disposition{block} }
4586 .sourceforge.net/tracker/download\.php</screen>
4594 <!-- ~~~~~ New section ~~~~~ -->
4595 <sect3 renderas="sect4" id="hide-if-modified-since">
4596 <title>hide-if-modified-since</title>
4602 <term>Typical use:</term>
4604 <para>Prevent yet another way to track the user's steps between sessions.</para>
4609 <term>Effect:</term>
4612 Deletes the <quote>If-Modified-Since:</quote> HTTP client header or modifies its value.
4619 <!-- Boolean, Parameterized, Multi-value -->
4621 <para>Parameterized.</para>
4626 <term>Parameter:</term>
4629 Keyword: <quote>block</quote>, or a user defined value that specifies a range of hours.
4638 Removing this header is useful for filter testing, where you want to force a real
4639 reload instead of getting status code <quote>304</quote>, which would cause the
4640 browser to use a cached copy of the page.
4643 Instead of removing the header, <literal>hide-if-modified-since</literal> can
4644 also add or subtract a random amount of time to/from the header's value.
4645 You specify a range of minutes where the random factor should be chosen from and
4646 <application>Privoxy</application> does the rest. A negative value means
4647 subtracting, a positive value adding.
4650 Randomizing the value of the <quote>If-Modified-Since:</quote> makes
4651 it less likely that the server can use the time as a cookie replacement,
4652 but you will run into caching problems if the random range is too high.
4655 It is a good idea to only use a small negative value and let
4656 <literal><link linkend="overwrite-last-modified">overwrite-last-modified</link></literal>
4657 handle the greater changes.
4660 It is also recommended to use this action together with
4661 <literal><link linkend="crunch-if-none-match">crunch-if-none-match</link></literal>,
4662 otherwise it's more or less pointless.
4668 <term>Example usage (section):</term>
4671 <screen># Let the browser revalidate but make tracking based on the time less likely.
4672 {+hide-if-modified-since{-60} \
4673 +overwrite-last-modified{randomize} \
4674 +crunch-if-none-match}
4683 <!-- ~~~~~ New section ~~~~~ -->
4684 <sect3 renderas="sect4" id="hide-forwarded-for-headers">
4685 <title>hide-forwarded-for-headers</title>
4688 <term>Typical use:</term>
4690 <para>Improve privacy by not forwarding the source of the request in the HTTP headers.</para>
4695 <term>Effect:</term>
4698 Deletes any existing <quote>X-Forwarded-for:</quote> HTTP header from client requests.
4705 <!-- Boolean, Parameterized, Multi-value -->
4707 <para>Boolean.</para>
4712 <term>Parameter:</term>
4724 It is safe and recommended to leave this on.
4730 <term>Example usage:</term>
4733 <screen>+hide-forwarded-for-headers</screen>
4741 <!-- ~~~~~ New section ~~~~~ -->
4742 <sect3 renderas="sect4" id="hide-from-header">
4743 <title>hide-from-header</title>
4747 <term>Typical use:</term>
4749 <para>Keep your (old and ill) browser from telling web servers your email address</para>
4754 <term>Effect:</term>
4757 Deletes any existing <quote>From:</quote> HTTP header, or replaces it with the
4765 <!-- Boolean, Parameterized, Multi-value -->
4767 <para>Parameterized.</para>
4772 <term>Parameter:</term>
4775 Keyword: <quote>block</quote>, or any user defined value.
4784 The keyword <quote>block</quote> will completely remove the header
4785 (not to be confused with the <literal><link linkend="block">block</link></literal>
4789 Alternately, you can specify any value you prefer to be sent to the web
4790 server. If you do, it is a matter of fairness not to use any address that
4791 is actually used by a real person.
4794 This action is rarely needed, as modern web browsers don't send
4795 <quote>From:</quote> headers anymore.
4801 <term>Example usage:</term>
4804 <screen>+hide-from-header{block}</screen> or
4805 <screen>+hide-from-header{spam-me-senseless@sittingduck.example.com}</screen>
4813 <!-- ~~~~~ New section ~~~~~ -->
4814 <sect3 renderas="sect4" id="hide-referrer">
4815 <title>hide-referrer</title>
4816 <anchor id="hide-referer">
4819 <term>Typical use:</term>
4821 <para>Conceal which link you followed to get to a particular site</para>
4826 <term>Effect:</term>
4829 Deletes the <quote>Referer:</quote> (sic) HTTP header from the client request,
4830 or replaces it with a forged one.
4837 <!-- Boolean, Parameterized, Multi-value -->
4839 <para>Parameterized.</para>
4844 <term>Parameter:</term>
4848 <para><quote>conditional-block</quote> to delete the header completely if the host has changed.</para>
4851 <para><quote>conditional-forge</quote> to forge the header if the host has changed.</para>
4854 <para><quote>block</quote> to delete the header unconditionally.</para>
4857 <para><quote>forge</quote> to pretend to be coming from the homepage of the server we are talking to.</para>
4860 <para>Any other string to set a user defined referrer.</para>
4870 <literal>conditional-block</literal> is the only parameter,
4871 that isn't easily detected in the server's log file. If it blocks the
4872 referrer, the request will look like the visitor used a bookmark or
4873 typed in the address directly.
4876 Leaving the referrer unmodified for requests on the same host
4877 allows the server owner to see the visitor's <quote>click path</quote>,
4878 but in most cases she could also get that information by comparing
4879 other parts of the log file: for example the User-Agent if it isn't
4880 a very common one, or the user's IP address if it doesn't change between
4884 Always blocking the referrer, or using a custom one, can lead to
4885 failures on servers that check the referrer before they answer any
4886 requests, in an attempt to prevent their content from being
4887 embedded or linked to elsewhere.
4890 Both <literal>conditional-block</literal> and <literal>forge</literal>
4891 will work with referrer checks, as long as content and valid referring page
4892 are on the same host. Most of the time that's the case.
4895 <literal>hide-referer</literal> is an alternate spelling of
4896 <literal>hide-referrer</literal> and the two can be can be freely
4897 substituted with each other. (<quote>referrer</quote> is the
4898 correct English spelling, however the HTTP specification has a bug - it
4899 requires it to be spelled as <quote>referer</quote>.)
4905 <term>Example usage:</term>
4908 <screen>+hide-referrer{forge}</screen> or
4909 <screen>+hide-referrer{http://www.yahoo.com/}</screen>
4917 <!-- ~~~~~ New section ~~~~~ -->
4918 <sect3 renderas="sect4" id="hide-user-agent">
4919 <title>hide-user-agent</title>
4923 <term>Typical use:</term>
4925 <para>Try to conceal your type of browser and client operating system</para>
4930 <term>Effect:</term>
4933 Replaces the value of the <quote>User-Agent:</quote> HTTP header
4934 in client requests with the specified value.
4941 <!-- Boolean, Parameterized, Multi-value -->
4943 <para>Parameterized.</para>
4948 <term>Parameter:</term>
4951 Any user-defined string.
4961 This can lead to problems on web sites that depend on looking at this header in
4962 order to customize their content for different browsers (which, by the
4963 way, is <emphasis>NOT</emphasis> the right thing to do: good web sites
4964 work browser-independently).
4968 Using this action in multi-user setups or wherever different types of
4969 browsers will access the same <application>Privoxy</application> is
4970 <emphasis>not recommended</emphasis>. In single-user, single-browser
4971 setups, you might use it to delete your OS version information from
4972 the headers, because it is an invitation to exploit known bugs for your
4973 OS. It is also occasionally useful to forge this in order to access
4974 sites that won't let you in otherwise (though there may be a good
4975 reason in some cases). Example of this: some MSN sites will not
4976 let <application>Mozilla</application> enter, yet forging to a
4977 <application>Netscape 6.1</application> user-agent works just fine.
4978 (Must be just a silly MS goof, I'm sure :-).
4981 More information on known user-agent strings can be found at
4982 <ulink url="http://www.user-agents.org/">http://www.user-agents.org/</ulink>
4984 <ulink url="http://en.wikipedia.org/wiki/User_agent">http://en.wikipedia.org/wiki/User_agent</ulink>.
4990 <term>Example usage:</term>
4993 <screen>+hide-user-agent{Netscape 6.1 (X11; I; Linux 2.4.18 i686)}</screen>
5001 <!-- ~~~~~ New section ~~~~~ -->
5002 <sect3 renderas="sect4" id="inspect-jpegs">
5003 <title>inspect-jpegs</title>
5006 <term>Typical use:</term>
5008 <para>Try to protect against a MS buffer over-run in JPEG processing</para>
5013 <term>Effect:</term>
5016 Protect against a known exploit
5023 <!-- Boolean, Parameterized, Multi-value -->
5025 <para>Boolean.</para>
5030 <term>Parameter:</term>
5042 See Microsoft Security Bulletin MS04-028. JPEG images are one of the most
5043 common image types found across the Internet. The exploit as described can
5044 allow execution of code on the target system, giving an attacker access
5045 to the system in question by merely planting an altered JPEG image, which
5046 would have no obvious indications of what lurks inside. This action
5047 tries to prevent this exploit if delivered through unencrypted HTTP.
5050 Note that the exploit mentioned is several years old
5051 and it's unlikely that your client is still vulnerable
5052 against it. This action may be removed in one of the
5060 <term>Example usage:</term>
5062 <para><screen>+inspect-jpegs</screen></para>
5069 <!-- ~~~~~ New section ~~~~~ -->
5070 <sect3 renderas="sect4" id="kill-popups">
5071 <title>kill-popups<anchor id="kill-popup"></title>
5075 <term>Typical use:</term>
5077 <para>Eliminate those annoying pop-up windows (deprecated)</para>
5082 <term>Effect:</term>
5085 While loading the document, replace JavaScript code that opens
5086 pop-up windows with (syntactically neutral) dummy code on the fly.
5093 <!-- Boolean, Parameterized, Multi-value -->
5095 <para>Boolean.</para>
5100 <term>Parameter:</term>
5112 This action is basically a built-in, hardwired special-purpose filter
5113 action, but there are important differences: For <literal>kill-popups</literal>,
5114 the document need not be buffered, so it can be incrementally rendered while
5115 downloading. But <literal>kill-popups</literal> doesn't catch as many pop-ups as
5117 linkend="FILTER-ALL-POPUPS">filter{<replaceable>all-popups</replaceable>}</link></literal>
5118 does and is not as smart as <literal><link
5119 linkend="FILTER-UNSOLICITED-POPUPS">filter{<replaceable>unsolicited-popups</replaceable>}</link>
5123 Think of it as a fast and efficient replacement for a filter that you
5124 can use if you don't want any filtering at all. Note that it doesn't make
5125 sense to combine it with any <literal><link linkend="filter">filter</link></literal> action,
5126 since as soon as one <literal><link linkend="filter">filter</link></literal> applies,
5127 the whole document needs to be buffered anyway, which destroys the advantage of
5128 the <literal>kill-popups</literal> action over its filter equivalent.
5131 Killing all pop-ups unconditionally is problematic. Many shops and banks rely on
5132 pop-ups to display forms, shopping carts etc, and the <literal><link
5133 linkend="FILTER-UNSOLICITED-POPUPS">filter{<replaceable>unsolicited-popups</replaceable>}</link>
5134 </literal> does a better job of catching only the unwanted ones.
5137 If the only kind of pop-ups that you want to kill are exit consoles (those
5138 <emphasis>really nasty</emphasis> windows that appear when you close an other
5139 one), you might want to use
5141 linkend="filter">filter</link>{<replaceable>js-annoyances</replaceable>}</literal>
5145 This action is most appropriate for browsers that don't have any controls
5146 for unwanted pop-ups. Not recommended for general usage.
5149 This action doesn't work very reliable and may be removed in future releases.
5155 <term>Example usage:</term>
5157 <para><screen>+kill-popups</screen></para>
5164 <!-- ~~~~~ New section ~~~~~ -->
5165 <sect3 renderas="sect4" id="limit-connect">
5166 <title>limit-connect</title>
5170 <term>Typical use:</term>
5172 <para>Prevent abuse of <application>Privoxy</application> as a TCP proxy relay or disable SSL for untrusted sites</para>
5177 <term>Effect:</term>
5180 Specifies to which ports HTTP CONNECT requests are allowable.
5187 <!-- Boolean, Parameterized, Multi-value -->
5189 <para>Parameterized.</para>
5194 <term>Parameter:</term>
5197 A comma-separated list of ports or port ranges (the latter using dashes, with the minimum
5198 defaulting to 0 and the maximum to 65K).
5207 By default, i.e. if no <literal>limit-connect</literal> action applies,
5208 <application>Privoxy</application> allows HTTP CONNECT requests to all
5209 ports. Use <literal>limit-connect</literal> if fine-grained control
5210 is desired for some or all destinations.
5213 The CONNECT methods exists in HTTP to allow access to secure websites
5214 (<quote>https://</quote> URLs) through proxies. It works very simply:
5215 the proxy connects to the server on the specified port, and then
5216 short-circuits its connections to the client and to the remote server.
5217 This means CONNECT-enabled proxies can be used as TCP relays very easily.
5220 <application>Privoxy</application> relays HTTPS traffic without seeing
5221 the decoded content. Websites can leverage this limitation to circumvent &my-app;'s
5222 filters. By specifying an invalid port range you can disable HTTPS entirely.
5228 <term>Example usages:</term>
5230 <!-- I had trouble getting the spacing to look right in my browser -->
5231 <!-- I probably have the wrong font setup, bollocks. -->
5232 <!-- Apparently the emphasis tag uses a proportional font no matter what -->
5234 <screen>+limit-connect{443} # Port 443 is OK.
5235 +limit-connect{80,443} # Ports 80 and 443 are OK.
5236 +limit-connect{-3, 7, 20-100, 500-} # Ports less than 3, 7, 20 to 100 and above 500 are OK.
5237 +limit-connect{-} # All ports are OK
5238 +limit-connect{,} # No HTTPS/SSL traffic is allowed</screen>
5245 <!-- ~~~~~ New section ~~~~~ -->
5246 <sect3 renderas="sect4" id="prevent-compression">
5247 <title>prevent-compression</title>
5251 <term>Typical use:</term>
5254 Ensure that servers send the content uncompressed, so it can be
5255 passed through <literal><link linkend="filter">filter</link></literal>s.
5261 <term>Effect:</term>
5264 Removes the Accept-Encoding header which can be used to ask for compressed transfer.
5271 <!-- Boolean, Parameterized, Multi-value -->
5273 <para>Boolean.</para>
5278 <term>Parameter:</term>
5290 More and more websites send their content compressed by default, which
5291 is generally a good idea and saves bandwidth. But the <literal><link
5292 linkend="filter">filter</link></literal>, <literal><link linkend="deanimate-gifs">deanimate-gifs</link></literal>
5293 and <literal><link linkend="kill-popups">kill-popups</link></literal> actions need
5294 access to the uncompressed data.
5297 When compiled with zlib support (available since &my-app; 3.0.7), content that should be
5298 filtered is decompressed on-the-fly and you don't have to worry about this action.
5299 If you are using an older &my-app; version, or one that hasn't been compiled with zlib
5300 support, this action can be used to convince the server to send the content uncompressed.
5303 Most text-based instances compress very well, the size is seldom decreased by less than 50%,
5304 for markup-heavy instances like news feeds saving more than 90% of the original size isn't
5308 Not using compression will therefore slow down the transfer, and you should only
5309 enable this action if you really need it. As of &my-app; 3.0.7 it's disabled in all
5310 predefined action settings.
5313 Note that some (rare) ill-configured sites don't handle requests for uncompressed
5314 documents correctly. Broken PHP applications tend to send an empty document body,
5315 some IIS versions only send the beginning of the content. If you enable
5316 <literal>prevent-compression</literal> per default, you might want to add
5317 exceptions for those sites. See the example for how to do that.
5323 <term>Example usage (sections):</term>
5327 # Selectively turn off compression, and enable a filter
5329 { +filter{tiny-textforms} +prevent-compression }
5330 # Match only these sites
5335 # Or instead, we could set a universal default:
5337 { +prevent-compression }
5340 # Then maybe make exceptions for broken sites:
5342 { -prevent-compression }
5343 .compusa.com/</screen>
5352 <!-- ~~~~~ New section ~~~~~ -->
5353 <sect3 renderas="sect4" id="overwrite-last-modified">
5354 <title>overwrite-last-modified</title>
5360 <term>Typical use:</term>
5362 <para>Prevent yet another way to track the user's steps between sessions.</para>
5367 <term>Effect:</term>
5370 Deletes the <quote>Last-Modified:</quote> HTTP server header or modifies its value.
5377 <!-- Boolean, Parameterized, Multi-value -->
5379 <para>Parameterized.</para>
5384 <term>Parameter:</term>
5387 One of the keywords: <quote>block</quote>, <quote>reset-to-request-time</quote>
5388 and <quote>randomize</quote>
5397 Removing the <quote>Last-Modified:</quote> header is useful for filter
5398 testing, where you want to force a real reload instead of getting status
5399 code <quote>304</quote>, which would cause the browser to reuse the old
5400 version of the page.
5403 The <quote>randomize</quote> option overwrites the value of the
5404 <quote>Last-Modified:</quote> header with a randomly chosen time
5405 between the original value and the current time. In theory the server
5406 could send each document with a different <quote>Last-Modified:</quote>
5407 header to track visits without using cookies. <quote>Randomize</quote>
5408 makes it impossible and the browser can still revalidate cached documents.
5411 <quote>reset-to-request-time</quote> overwrites the value of the
5412 <quote>Last-Modified:</quote> header with the current time. You could use
5413 this option together with
5414 <literal><link linkend="hide-if-modified-since">hided-if-modified-since</link></literal>
5415 to further customize your random range.
5418 The preferred parameter here is <quote>randomize</quote>. It is safe
5419 to use, as long as the time settings are more or less correct.
5420 If the server sets the <quote>Last-Modified:</quote> header to the time
5421 of the request, the random range becomes zero and the value stays the same.
5422 Therefore you should later randomize it a second time with
5423 <literal><link linkend="hide-if-modified-since">hided-if-modified-since</link></literal>,
5427 It is also recommended to use this action together with
5428 <literal><link linkend="crunch-if-none-match">crunch-if-none-match</link></literal>.
5434 <term>Example usage:</term>
5437 <screen># Let the browser revalidate without being tracked across sessions
5438 { +hide-if-modified-since{-60} \
5439 +overwrite-last-modified{randomize} \
5440 +crunch-if-none-match}
5449 <!-- ~~~~~ New section ~~~~~ -->
5450 <sect3 renderas="sect4" id="redirect">
5451 <title>redirect</title>
5457 <term>Typical use:</term>
5460 Redirect requests to other sites.
5466 <term>Effect:</term>
5469 Convinces the browser that the requested document has been moved
5470 to another location and the browser should get it from there.
5477 <!-- Boolean, Parameterized, Multi-value -->
5479 <para>Parameterized</para>
5484 <term>Parameter:</term>
5487 An absolute URL or a single pcrs command.
5496 Requests to which this action applies are answered with a
5497 HTTP redirect to URLs of your choosing. The new URL is
5498 either provided as parameter, or derived by applying a
5499 single pcrs command to the original URL.
5502 This action will be ignored if you use it together with
5503 <literal><link linkend="block">block</link></literal>.
5504 It can be combined with
5505 <literal><link linkend="fast-redirects">fast-redirects{check-decoded-url}</link></literal>
5506 to redirect to a decoded version of a rewritten URL.
5509 Use this action carefully, make sure not to create redirection loops
5510 and be aware that using your own redirects might make it
5511 possible to fingerprint your requests.
5517 <term>Example usages:</term>
5520 <screen># Replace example.com's style sheet with another one
5521 { +redirect{http://localhost/css-replacements/example.com.css} }
5522 example.com/stylesheet\.css
5524 # Create a short, easy to remember nickname for a favorite site
5525 # (relies on the browser accept and forward invalid URLs to &my-app;)
5526 { +redirect{http://www.privoxy.org/user-manual/actions-file.html} }
5529 # Always use the expanded view for Undeadly.org articles
5530 # (Note the $ at the end of the URL pattern to make sure
5531 # the request for the rewritten URL isn't redirected as well)
5532 {+redirect{s@$@&mode=expanded@}}
5533 undeadly.org/cgi\?action=article&sid=\d*$</screen>
5542 <!-- ~~~~~ New section ~~~~~ -->
5543 <sect3 renderas="sect4" id="send-vanilla-wafer">
5544 <title>send-vanilla-wafer</title>
5548 <term>Typical use:</term>
5551 Feed log analysis scripts with useless data.
5557 <term>Effect:</term>
5560 Sends a cookie with each request stating that you do not accept any copyright
5561 on cookies sent to you, and asking the site operator not to track you.
5568 <!-- Boolean, Parameterized, Multi-value -->
5570 <para>Boolean.</para>
5575 <term>Parameter:</term>
5587 The vanilla wafer is a (relatively) unique header and could conceivably be used to track you.
5590 This action is rarely used and not enabled in the default configuration.
5596 <term>Example usage:</term>
5599 <screen>+send-vanilla-wafer</screen>
5608 <!-- ~~~~~ New section ~~~~~ -->
5609 <sect3 renderas="sect4" id="send-wafer">
5610 <title>send-wafer</title>
5614 <term>Typical use:</term>
5617 Send custom cookies or feed log analysis scripts with even more useless data.
5623 <term>Effect:</term>
5626 Sends a custom, user-defined cookie with each request.
5633 <!-- Boolean, Parameterized, Multi-value -->
5635 <para>Multi-value.</para>
5640 <term>Parameter:</term>
5643 A string of the form <quote><replaceable class="option">name</replaceable>=<replaceable
5644 class="parameter">value</replaceable></quote>.
5653 Being multi-valued, multiple instances of this action can apply to the same request,
5654 resulting in multiple cookies being sent.
5657 This action is rarely used and not enabled in the default configuration.
5662 <term>Example usage (section):</term>
5665 <screen>{+send-wafer{UsingPrivoxy=true}}
5666 my-internal-testing-server.void</screen>
5674 <!-- ~~~~~ New section ~~~~~ -->
5675 <sect3 renderas="sect4" id="server-header-filter">
5676 <title>server-header-filter</title>
5680 <term>Typical use:</term>
5683 Rewrite or remove single server headers.
5689 <term>Effect:</term>
5692 All server headers to which this action applies are filtered on-the-fly
5693 through the specified regular expression based substitutions.
5700 <!-- boolean, parameterized, Multi-value -->
5702 <para>Parameterized.</para>
5707 <term>Parameter:</term>
5710 The name of a server-header filter, as defined in one of the
5711 <link linkend="filter-file">filter files</link>.
5720 Server-header filters are applied to each header on its own, not to
5721 all at once. This makes it easier to diagnose problems, but on the downside
5722 you can't write filters that only change header x if header y's value is z.
5723 You can do that by using tags though.
5726 Server-header filters are executed after the other header actions have finished
5727 and use their output as input.
5730 Please refer to the <link linkend="filter-file">filter file chapter</link>
5731 to learn which server-header filters are available by default, and how to
5738 <term>Example usage (section):</term>
5742 {+server-header-filter{html-to-xml}}
5743 example.org/xml-instance-that-is-delivered-as-html
5745 {+server-header-filter{xml-to-html}}
5746 example.org/instance-that-is-delivered-as-xml-but-is-not
5756 <!-- ~~~~~ New section ~~~~~ -->
5757 <sect3 renderas="sect4" id="server-header-tagger">
5758 <title>server-header-tagger</title>
5762 <term>Typical use:</term>
5765 Enable or disable filters based on the Content-Type header.
5771 <term>Effect:</term>
5774 Server headers to which this action applies are filtered on-the-fly through
5775 the specified regular expression based substitutions, the result is used as
5783 <!-- boolean, parameterized, Multi-value -->
5785 <para>Parameterized.</para>
5790 <term>Parameter:</term>
5793 The name of a server-header tagger, as defined in one of the
5794 <link linkend="filter-file">filter files</link>.
5803 Server-header taggers are applied to each header on its own,
5804 and as the header isn't modified, each tagger <quote>sees</quote>
5808 Server-header taggers are executed before all other header actions
5809 that modify server headers. Their tags can be used to control
5810 all of the other server-header actions, the content filters
5811 and the crunch actions (<link linkend="redirect">redirect</link>
5812 and <link linkend="block">block</link>).
5815 Obviously crunching based on tags created by server-header taggers
5816 doesn't prevent the request from showing up in the server's log file.
5823 <term>Example usage (section):</term>
5827 # Tag every request with the content type declared by the server
5828 {+server-header-tagger{content-type}}
5839 <!-- ~~~~~ New section ~~~~~ -->
5840 <sect3 renderas="sect4" id="session-cookies-only">
5841 <title>session-cookies-only</title>
5845 <term>Typical use:</term>
5848 Allow only temporary <quote>session</quote> cookies (for the current
5849 browser session <emphasis>only</emphasis>).
5855 <term>Effect:</term>
5858 Deletes the <quote>expires</quote> field from <quote>Set-Cookie:</quote>
5859 server headers. Most browsers will not store such cookies permanently and
5860 forget them in between sessions.
5867 <!-- Boolean, Parameterized, Multi-value -->
5869 <para>Boolean.</para>
5874 <term>Parameter:</term>
5886 This is less strict than <literal><link linkend="crunch-incoming-cookies">crunch-incoming-cookies</link></literal> /
5887 <literal><link linkend="crunch-outgoing-cookies">crunch-outgoing-cookies</link></literal> and allows you to browse
5888 websites that insist or rely on setting cookies, without compromising your privacy too badly.
5891 Most browsers will not permanently store cookies that have been processed by
5892 <literal>session-cookies-only</literal> and will forget about them between sessions.
5893 This makes profiling cookies useless, but won't break sites which require cookies so
5894 that you can log in for transactions. This is generally turned on for all
5895 sites, and is the recommended setting.
5898 It makes <emphasis>no sense at all</emphasis> to use <literal>session-cookies-only</literal>
5899 together with <literal><link linkend="crunch-incoming-cookies">crunch-incoming-cookies</link></literal> or
5900 <literal><link linkend="crunch-outgoing-cookies">crunch-outgoing-cookies</link></literal>. If you do, cookies
5901 will be plainly killed.
5904 Note that it is up to the browser how it handles such cookies without an <quote>expires</quote>
5905 field. If you use an exotic browser, you might want to try it out to be sure.
5908 This setting also has no effect on cookies that may have been stored
5909 previously by the browser before starting <application>Privoxy</application>.
5910 These would have to be removed manually.
5913 <application>Privoxy</application> also uses
5914 the <link linkend="filter-content-cookies">content-cookies filter</link>
5915 to block some types of cookies. Content cookies are not effected by
5916 <literal>session-cookies-only</literal>.
5922 <term>Example usage:</term>
5925 <screen>+session-cookies-only</screen>
5933 <!-- ~~~~~ New section ~~~~~ -->
5934 <sect3 renderas="sect4" id="set-image-blocker">
5935 <title>set-image-blocker</title>
5939 <term>Typical use:</term>
5941 <para>Choose the replacement for blocked images</para>
5946 <term>Effect:</term>
5949 This action alone doesn't do anything noticeable. If <emphasis>both</emphasis>
5950 <literal><link linkend="block">block</link></literal> <emphasis>and</emphasis> <literal><link
5951 linkend="handle-as-image">handle-as-image</link></literal> <emphasis>also</emphasis>
5952 apply, i.e. if the request is to be blocked as an image,
5953 <emphasis>then</emphasis> the parameter of this action decides what will be
5954 sent as a replacement.
5961 <!-- Boolean, Parameterized, Multi-value -->
5963 <para>Parameterized.</para>
5968 <term>Parameter:</term>
5973 <quote>pattern</quote> to send a built-in checkerboard pattern image. The image is visually
5974 decent, scales very well, and makes it obvious where banners were busted.
5979 <quote>blank</quote> to send a built-in transparent image. This makes banners disappear
5980 completely, but makes it hard to detect where <application>Privoxy</application> has blocked
5981 images on a given page and complicates troubleshooting if <application>Privoxy</application>
5982 has blocked innocent images, like navigation icons.
5987 <quote><replaceable class="parameter">target-url</replaceable></quote> to
5988 send a redirect to <replaceable class="parameter">target-url</replaceable>. You can redirect
5989 to any image anywhere, even in your local filesystem via <quote>file:///</quote> URL.
5990 (But note that not all browsers support redirecting to a local file system).
5993 A good application of redirects is to use special <application>Privoxy</application>-built-in
5994 URLs, which send the built-in images, as <replaceable class="parameter">target-url</replaceable>.
5995 This has the same visual effect as specifying <quote>blank</quote> or <quote>pattern</quote> in
5996 the first place, but enables your browser to cache the replacement image, instead of requesting
5997 it over and over again.
6008 The URLs for the built-in images are <quote>http://config.privoxy.org/send-banner?type=<replaceable
6009 class="parameter">type</replaceable></quote>, where <replaceable class="parameter">type</replaceable> is
6010 either <quote>blank</quote> or <quote>pattern</quote>.
6013 There is a third (advanced) type, called <quote>auto</quote>. It is <emphasis>NOT</emphasis> to be
6014 used in <literal>set-image-blocker</literal>, but meant for use from <link linkend="filter-file">filters</link>.
6015 Auto will select the type of image that would have applied to the referring page, had it been an image.
6021 <term>Example usage:</term>
6027 <screen>+set-image-blocker{pattern}</screen>
6030 Redirect to the BSD daemon:
6033 <screen>+set-image-blocker{http://www.freebsd.org/gifs/dae_up3.gif}</screen>
6036 Redirect to the built-in pattern for better caching:
6039 <screen>+set-image-blocker{http://config.privoxy.org/send-banner?type=pattern}</screen>
6047 <!-- ~~~~~ New section ~~~~~ -->
6049 <title>Summary</title>
6051 Note that many of these actions have the potential to cause a page to
6052 misbehave, possibly even not to display at all. There are many ways
6053 a site designer may choose to design his site, and what HTTP header
6054 content, and other criteria, he may depend on. There is no way to have hard
6055 and fast rules for all sites. See the <link
6056 linkend="ACTIONSANAT">Appendix</link> for a brief example on troubleshooting
6062 <!-- ~~~~~ New section ~~~~~ -->
6063 <sect2 id="aliases">
6064 <title>Aliases</title>
6066 Custom <quote>actions</quote>, known to <application>Privoxy</application>
6067 as <quote>aliases</quote>, can be defined by combining other actions.
6068 These can in turn be invoked just like the built-in actions.
6069 Currently, an alias name can contain any character except space, tab,
6071 <quote>{</quote> and <quote>}</quote>, but we <emphasis>strongly
6072 recommend</emphasis> that you only use <quote>a</quote> to <quote>z</quote>,
6073 <quote>0</quote> to <quote>9</quote>, <quote>+</quote>, and <quote>-</quote>.
6074 Alias names are not case sensitive, and are not required to start with a
6075 <quote>+</quote> or <quote>-</quote> sign, since they are merely textually
6079 Aliases can be used throughout the actions file, but they <emphasis>must be
6080 defined in a special section at the top of the file!</emphasis>
6081 And there can only be one such section per actions file. Each actions file may
6082 have its own alias section, and the aliases defined in it are only visible
6086 There are two main reasons to use aliases: One is to save typing for frequently
6087 used combinations of actions, the other one is a gain in flexibility: If you
6088 decide once how you want to handle shops by defining an alias called
6089 <quote>shop</quote>, you can later change your policy on shops in
6090 <emphasis>one</emphasis> place, and your changes will take effect everywhere
6091 in the actions file where the <quote>shop</quote> alias is used. Calling aliases
6092 by their purpose also makes your actions files more readable.
6095 Currently, there is one big drawback to using aliases, though:
6096 <application>Privoxy</application>'s built-in web-based action file
6097 editor honors aliases when reading the actions files, but it expands
6098 them before writing. So the effects of your aliases are of course preserved,
6099 but the aliases themselves are lost when you edit sections that use aliases
6104 Now let's define some aliases...
6109 # Useful custom aliases we can use later.
6111 # Note the (required!) section header line and that this section
6112 # must be at the top of the actions file!
6116 # These aliases just save typing later:
6117 # (Note that some already use other aliases!)
6119 +crunch-all-cookies = +<link linkend="CRUNCH-INCOMING-COOKIES">crunch-incoming-cookies</link> +<link linkend="CRUNCH-OUTGOING-COOKIES">crunch-outgoing-cookies</link>
6120 -crunch-all-cookies = -<link linkend="CRUNCH-INCOMING-COOKIES">crunch-incoming-cookies</link> -<link linkend="CRUNCH-OUTGOING-COOKIES">crunch-outgoing-cookies</link>
6121 +block-as-image = +block{Blocked image.} +handle-as-image
6122 allow-all-cookies = -crunch-all-cookies -<link linkend="SESSION-COOKIES-ONLY">session-cookies-only</link> -<link linkend="FILTER-CONTENT-COOKIES">filter{content-cookies}</link>
6124 # These aliases define combinations of actions
6125 # that are useful for certain types of sites:
6127 fragile = -<link linkend="BLOCK">block</link> -<link linkend="FILTER">filter</link> -crunch-all-cookies -<link linkend="FAST-REDIRECTS">fast-redirects</link> -<link linkend="HIDE-REFERER">hide-referrer</link> -<link linkend="KILL-POPUPS">kill-popups</link> -<link linkend="PREVENT-COMPRESSION">prevent-compression</link>
6129 shop = -crunch-all-cookies -<link linkend="FILTER-ALL-POPUPS">filter{all-popups}</link> -<link linkend="KILL-POPUPS">kill-popups</link>
6131 # Short names for other aliases, for really lazy people ;-)
6133 c0 = +crunch-all-cookies
6134 c1 = -crunch-all-cookies</screen>
6138 ...and put them to use. These sections would appear in the lower part of an
6139 actions file and define exceptions to the default actions (as specified further
6140 up for the <quote>/</quote> pattern):
6145 # These sites are either very complex or very keen on
6146 # user data and require minimal interference to work:
6149 .office.microsoft.com
6150 .windowsupdate.microsoft.com
6151 # Gmail is really mail.google.com, not gmail.com
6155 # Allow cookies (for setting and retrieving your customer data)
6159 .worldpay.com # for quietpc.com
6162 # These shops require pop-ups:
6164 {-kill-popups -filter{all-popups} -filter{unsolicited-popups}}
6166 .overclockers.co.uk</screen>
6170 Aliases like <quote>shop</quote> and <quote>fragile</quote> are typically used for
6171 <quote>problem</quote> sites that require more than one action to be disabled
6172 in order to function properly.
6178 <!-- ~~~~~ New section ~~~~~ -->
6179 <sect2 id="act-examples">
6180 <title>Actions Files Tutorial</title>
6182 The above chapters have shown <link linkend="actions-file">which actions files
6183 there are and how they are organized</link>, how actions are <link
6184 linkend="actions">specified</link> and <link linkend="actions-apply">applied
6185 to URLs</link>, how <link linkend="af-patterns">patterns</link> work, and how to
6186 define and use <link linkend="aliases">aliases</link>. Now, let's look at an
6187 example <filename>default.action</filename> and <filename>user.action</filename>
6188 file and see how all these pieces come together:
6191 <sect3><title>default.action</title>
6194 Every config file should start with a short comment stating its purpose:
6198 <screen># Sample default.action file <ijbswa-developers@lists.sourceforge.net></screen>
6202 Then, since this is the <filename>default.action</filename> file, the
6203 first section is a special section for internal use that you needn't
6204 change or worry about:
6209 ##########################################################################
6210 # Settings -- Don't change! For internal Privoxy use ONLY.
6211 ##########################################################################
6214 for-privoxy-version=3.0</screen>
6218 After that comes the (optional) alias section. We'll use the example
6219 section from the above <link linkend="aliases">chapter on aliases</link>,
6220 that also explains why and how aliases are used:
6225 ##########################################################################
6227 ##########################################################################
6230 # These aliases just save typing later:
6231 # (Note that some already use other aliases!)
6233 +crunch-all-cookies = +<link linkend="CRUNCH-INCOMING-COOKIES">crunch-incoming-cookies</link> +<link linkend="CRUNCH-OUTGOING-COOKIES">crunch-outgoing-cookies</link>
6234 -crunch-all-cookies = -<link linkend="CRUNCH-INCOMING-COOKIES">crunch-incoming-cookies</link> -<link linkend="CRUNCH-OUTGOING-COOKIES">crunch-outgoing-cookies</link>
6235 +block-as-image = +block{Blocked image.} +handle-as-image
6236 mercy-for-cookies = -crunch-all-cookies -<link linkend="SESSION-COOKIES-ONLY">session-cookies-only</link> -<link linkend="FILTER-CONTENT-COOKIES">filter{content-cookies}</link>
6238 # These aliases define combinations of actions
6239 # that are useful for certain types of sites:
6241 fragile = -<link linkend="BLOCK">block</link> -<link linkend="FILTER">filter</link> -crunch-all-cookies -<link linkend="FAST-REDIRECTS">fast-redirects</link> -<link linkend="HIDE-REFERER">hide-referrer</link> -<link linkend="KILL-POPUPS">kill-popups</link>
6242 shop = -crunch-all-cookies -<link linkend="FILTER-ALL-POPUPS">filter{all-popups}</link> -<link linkend="KILL-POPUPS">kill-popups</link></screen>
6246 Now come the regular sections, i.e. sets of actions, accompanied
6247 by URL patterns to which they apply. Remember <emphasis>all actions
6248 are disabled when matching starts</emphasis>, so we have to explicitly
6249 enable the ones we want.
6253 The first regular section is probably the most important. It has only
6254 one pattern, <quote><literal>/</literal></quote>, but this pattern
6255 <link linkend="af-patterns">matches all URLs</link>. Therefore, the
6256 set of actions used in this <quote>default</quote> section <emphasis>will
6257 be applied to all requests as a start</emphasis>. It can be partly or
6258 wholly overridden by later matches further down this file, or in user.action,
6259 but it will still be largely responsible for your overall browsing
6264 Again, at the start of matching, all actions are disabled, so there is
6265 no need to disable any actions here. (Remember: a <quote>+</quote>
6266 preceding the action name enables the action, a <quote>-</quote> disables!).
6267 Also note how this long line has been made more readable by splitting it into
6268 multiple lines with line continuation.
6273 ##########################################################################
6274 # "Defaults" section:
6275 ##########################################################################
6277 +<link linkend="DEANIMATE-GIFS">deanimate-gifs</link> \
6278 +<link linkend="FILTER-HTML-ANNOYANCES">filter{html-annoyances}</link> \
6279 +<link linkend="FILTER-REFRESH-TAGS">filter{refresh-tags}</link> \
6280 +<link linkend="FILTER-WEBBUGS">filter{webbugs}</link> \
6281 +<link linkend="FILTER-IE-EXPLOITS">filter{ie-exploits}</link> \
6282 +<link linkend="HIDE-FORWARDED-FOR-HEADERS">hide-forwarded-for-headers</link> \
6283 +<link linkend="HIDE-FROM-HEADER">hide-from-header{block}</link> \
6284 +<link linkend="HIDE-REFERER">hide-referrer{forge}</link> \
6285 +<link linkend="PREVENT-COMPRESSION">prevent-compression</link> \
6286 +<link linkend="SESSION-COOKIES-ONLY">session-cookies-only</link> \
6287 +<link linkend="SET-IMAGE-BLOCKER">set-image-blocker{pattern}</link> \
6289 / # forward slash will match *all* potential URL patterns.</screen>
6293 The default behavior is now set.
6295 This needs rewording, but it can wait for now.
6298 Note that some actions, like not hiding
6299 the user agent, are part of a <quote>general policy</quote> that applies
6300 universally and won't get any exceptions defined later. Other choices,
6301 like not blocking (which is <emphasis>understandably</emphasis> the
6302 default!) need exceptions, i.e. we need to specify explicitly what we
6303 want to block in later sections.
6308 The first of our specialized sections is concerned with <quote>fragile</quote>
6309 sites, i.e. sites that require minimum interference, because they are either
6310 very complex or very keen on tracking you (and have mechanisms in place that
6311 make them unusable for people who avoid being tracked). We will simply use
6312 our pre-defined <literal>fragile</literal> alias instead of stating the list
6313 of actions explicitly:
6318 ##########################################################################
6319 # Exceptions for sites that'll break under the default action set:
6320 ##########################################################################
6322 # "Fragile" Use a minimum set of actions for these sites (see alias above):
6325 .office.microsoft.com # surprise, surprise!
6326 .windowsupdate.microsoft.com
6327 mail.google.com</screen>
6331 Shopping sites are not as fragile, but they typically
6332 require cookies to log in, and pop-up windows for shopping
6333 carts or item details. Again, we'll use a pre-defined alias:
6342 .worldpay.com # for quietpc.com
6344 .scan.co.uk</screen>
6347 <!-- No longer needed BEGIN OF COMMENTED OUT BLOCK
6350 Then, there are sites which rely on pop-up windows (yuck!) to work.
6351 Since we made pop-up-killing our default above, we need to make exceptions
6352 now. <ulink url="http://www.mozilla.org/">Mozilla</ulink> users, who
6353 can turn on smart handling of unwanted pop-ups in their browsers, can
6355 -<literal><link linkend="FILTER-ALL-POPUPS">filter{popups}</link></literal> (and
6356 -<literal><link linkend="KILL-POPUPS">kill-popups</link></literal>) above
6357 and hence don't need this section. Anyway, disabling an already disabled
6358 action doesn't hurt, so we'll define our exceptions regardless of what was
6359 chosen in the defaults section:
6364 # These sites require pop-ups too :(
6366 { -<link linkend="KILL-POPUPS">kill-popups</link> -<link linkend="FILTER-ALL-POPUPS">filter{popups}</link> }
6369 .deutsche-bank-24.de</screen>
6372 END OF COMMENTED OUT BLOCK -->
6375 The <literal><link linkend="FAST-REDIRECTS">fast-redirects</link></literal>
6376 action, which we enabled per default above, breaks some sites. So disable
6377 it for popular sites where we know it misbehaves:
6382 { -<link linkend="FAST-REDIRECTS">fast-redirects</link> }
6386 .altavista.com/.*(like|url|link):http
6387 .altavista.com/trans.*urltext=http
6388 .nytimes.com</screen>
6392 It is important that <application>Privoxy</application> knows which
6393 URLs belong to images, so that <emphasis>if</emphasis> they are to
6394 be blocked, a substitute image can be sent, rather than an HTML page.
6395 Contacting the remote site to find out is not an option, since it
6396 would destroy the loading time advantage of banner blocking, and it
6397 would feed the advertisers (in terms of money <emphasis>and</emphasis>
6398 information). We can mark any URL as an image with the <literal><link
6399 linkend="handle-as-image">handle-as-image</link></literal> action,
6400 and marking all URLs that end in a known image file extension is a
6406 ##########################################################################
6408 ##########################################################################
6410 # Define which file types will be treated as images, in case they get
6411 # blocked further down this file:
6413 { +<link linkend="HANDLE-AS-IMAGE">handle-as-image</link> }
6414 /.*\.(gif|jpe?g|png|bmp|ico)$</screen>
6418 And then there are known banner sources. They often use scripts to
6419 generate the banners, so it won't be visible from the URL that the
6420 request is for an image. Hence we block them <emphasis>and</emphasis>
6421 mark them as images in one go, with the help of our
6422 <literal>+block-as-image</literal> alias defined above. (We could of
6423 course just as well use <literal>+<link linkend="block">block</link>
6424 +<link linkend="handle-as-image">handle-as-image</link></literal> here.)
6425 Remember that the type of the replacement image is chosen by the
6426 <literal><link linkend="set-image-blocker">set-image-blocker</link></literal>
6427 action. Since all URLs have matched the default section with its
6428 <literal>+<link linkend="set-image-blocker">set-image-blocker</link>{pattern}</literal>
6429 action before, it still applies and needn't be repeated:
6434 # Known ad generators:
6439 .ad.*.doubleclick.net
6440 .a.yimg.com/(?:(?!/i/).)*$
6441 .a[0-9].yimg.com/(?:(?!/i/).)*$
6447 One of the most important jobs of <application>Privoxy</application>
6448 is to block banners. Many of these can be <quote>blocked</quote>
6449 by the <literal><link linkend="filter">filter</link>{banners-by-size}</literal>
6450 action, which we enabled above, and which deletes the references to banner
6451 images from the pages while they are loaded, so the browser doesn't request
6452 them anymore, and hence they don't need to be blocked here. But this naturally
6453 doesn't catch all banners, and some people choose not to use filters, so we
6454 need a comprehensive list of patterns for banner URLs here, and apply the
6455 <literal><link linkend="block">block</link></literal> action to them.
6458 First comes many generic patterns, which do most of the work, by
6459 matching typical domain and path name components of banners. Then comes
6460 a list of individual patterns for specific sites, which is omitted here
6461 to keep the example short:
6466 ##########################################################################
6467 # Block these fine banners:
6468 ##########################################################################
6469 { <link linkend="BLOCK">+block{Banner ads.}</link> }
6477 /.*count(er)?\.(pl|cgi|exe|dll|asp|php[34]?)
6478 /(?:.*/)?(publicite|werbung|rekla(ma|me|am)|annonse|maino(kset|nta|s)?)/
6480 # Site-specific patterns (abbreviated):
6482 .hitbox.com</screen>
6486 It's quite remarkable how many advertisers actually call their banner
6487 servers ads.<replaceable>company</replaceable>.com, or call the directory
6488 in which the banners are stored simply <quote>banners</quote>. So the above
6489 generic patterns are surprisingly effective.
6492 But being very generic, they necessarily also catch URLs that we don't want
6493 to block. The pattern <literal>.*ads.</literal> e.g. catches
6494 <quote>nasty-<emphasis>ads</emphasis>.nasty-corp.com</quote> as intended,
6495 but also <quote>downlo<emphasis>ads</emphasis>.sourcefroge.net</quote> or
6496 <quote><emphasis>ads</emphasis>l.some-provider.net.</quote> So here come some
6497 well-known exceptions to the <literal>+<link linkend="BLOCK">block</link></literal>
6501 Note that these are exceptions to exceptions from the default! Consider the URL
6502 <quote>downloads.sourcefroge.net</quote>: Initially, all actions are deactivated,
6503 so it wouldn't get blocked. Then comes the defaults section, which matches the
6504 URL, but just deactivates the <literal><link linkend="BLOCK">block</link></literal>
6505 action once again. Then it matches <literal>.*ads.</literal>, an exception to the
6506 general non-blocking policy, and suddenly
6507 <literal><link linkend="BLOCK">+block</link></literal> applies. And now, it'll match
6508 <literal>.*loads.</literal>, where <literal><link linkend="BLOCK">-block</link></literal>
6509 applies, so (unless it matches <emphasis>again</emphasis> further down) it ends up
6510 with no <literal><link linkend="BLOCK">block</link></literal> action applying.
6515 ##########################################################################
6516 # Save some innocent victims of the above generic block patterns:
6517 ##########################################################################
6521 { -<link linkend="BLOCK">block</link> }
6522 adv[io]*. # (for advogato.org and advice.*)
6523 adsl. # (has nothing to do with ads)
6524 adobe. # (has nothing to do with ads either)
6525 ad[ud]*. # (adult.* and add.*)
6526 .edu # (universities don't host banners (yet!))
6527 .*loads. # (downloads, uploads etc)
6535 www.globalintersec.com/adv # (adv = advanced)
6536 www.ugu.com/sui/ugu/adv</screen>
6540 Filtering source code can have nasty side effects,
6541 so make an exception for our friends at sourceforge.net,
6542 and all paths with <quote>cvs</quote> in them. Note that
6543 <literal>-<link linkend="FILTER">filter</link></literal>
6544 disables <emphasis>all</emphasis> filters in one fell swoop!
6549 # Don't filter code!
6551 { -<link linkend="FILTER">filter</link> }
6556 .sourceforge.net</screen>
6560 The actual <filename>default.action</filename> is of course much more
6561 comprehensive, but we hope this example made clear how it works.
6566 <sect3><title>user.action</title>
6569 So far we are painting with a broad brush by setting general policies,
6570 which would be a reasonable starting point for many people. Now,
6571 you might want to be more specific and have customized rules that
6572 are more suitable to your personal habits and preferences. These would
6573 be for narrowly defined situations like your ISP or your bank, and should
6574 be placed in <filename>user.action</filename>, which is parsed after all other
6575 actions files and hence has the last word, over-riding any previously
6576 defined actions. <filename>user.action</filename> is also a
6577 <emphasis>safe</emphasis> place for your personal settings, since
6578 <filename>default.action</filename> is actively maintained by the
6579 <application>Privoxy</application> developers and you'll probably want
6580 to install updated versions from time to time.
6584 So let's look at a few examples of things that one might typically do in
6585 <filename>user.action</filename>:
6589 <!-- brief sample user.action here -->
6593 # My user.action file. <fred@example.com></screen>
6597 As <link linkend="aliases">aliases</link> are local to the actions
6598 file that they are defined in, you can't use the ones from
6599 <filename>default.action</filename>, unless you repeat them here:
6604 # Aliases are local to the file they are defined in.
6605 # (Re-)define aliases for this file:
6609 # These aliases just save typing later, and the alias names should
6610 # be self explanatory.
6612 +crunch-all-cookies = +crunch-incoming-cookies +crunch-outgoing-cookies
6613 -crunch-all-cookies = -crunch-incoming-cookies -crunch-outgoing-cookies
6614 allow-all-cookies = -crunch-all-cookies -session-cookies-only
6615 allow-popups = -filter{all-popups} -kill-popups
6616 +block-as-image = +block{Blocked as image.} +handle-as-image
6617 -block-as-image = -block
6619 # These aliases define combinations of actions that are useful for
6620 # certain types of sites:
6622 fragile = -block -crunch-all-cookies -filter -fast-redirects -hide-referrer -kill-popups
6623 shop = -crunch-all-cookies allow-popups
6625 # Allow ads for selected useful free sites:
6627 allow-ads = -block -filter{banners-by-size} -filter{banners-by-link}
6629 # Alias for specific file types that are text, but might have conflicting
6630 # MIME types. We want the browser to force these to be text documents.
6631 handle-as-text = -<link linkend="FILTER">filter</link> +-<link linkend="content-type-overwrite">content-type-overwrite{text/plain}</link> +-<link linkend="FORCE-TEXT-MODE">force-text-mode</link> -<link linkend="HIDE-CONTENT-DISPOSITION">hide-content-disposition</link></screen>
6636 Say you have accounts on some sites that you visit regularly, and
6637 you don't want to have to log in manually each time. So you'd like
6638 to allow persistent cookies for these sites. The
6639 <literal>allow-all-cookies</literal> alias defined above does exactly
6640 that, i.e. it disables crunching of cookies in any direction, and the
6641 processing of cookies to make them only temporary.
6646 { allow-all-cookies }
6650 .redhat.com</screen>
6654 Your bank is allergic to some filter, but you don't know which, so you disable them all:
6659 { -<link linkend="FILTER">filter</link> }
6660 .your-home-banking-site.com</screen>
6664 Some file types you may not want to filter for various reasons:
6669 # Technical documentation is likely to contain strings that might
6670 # erroneously get altered by the JavaScript-oriented filters:
6675 # And this stupid host sends streaming video with a wrong MIME type,
6676 # so that Privoxy thinks it is getting HTML and starts filtering:
6678 stupid-server.example.com/</screen>
6682 Example of a simple <link linkend="BLOCK">block</link> action. Say you've
6683 seen an ad on your favourite page on example.com that you want to get rid of.
6684 You have right-clicked the image, selected <quote>copy image location</quote>
6685 and pasted the URL below while removing the leading http://, into a
6686 <literal>{ +block{} }</literal> section. Note that <literal>{ +handle-as-image
6687 }</literal> need not be specified, since all URLs ending in
6688 <literal>.gif</literal> will be tagged as images by the general rules as set
6689 in default.action anyway:
6694 { +<link linkend="BLOCK">block</link>{Nasty ads.} }
6695 www.example.com/nasty-ads/sponsor\.gif
6696 another.example.net/more/junk/here/</screen>
6700 The URLs of dynamically generated banners, especially from large banner
6701 farms, often don't use the well-known image file name extensions, which
6702 makes it impossible for <application>Privoxy</application> to guess
6703 the file type just by looking at the URL.
6704 You can use the <literal>+block-as-image</literal> alias defined above for
6706 Note that objects which match this rule but then turn out NOT to be an
6707 image are typically rendered as a <quote>broken image</quote> icon by the
6708 browser. Use cautiously.
6717 ar.atwola.com/</screen>
6721 Now you noticed that the default configuration breaks Forbes Magazine,
6722 but you were too lazy to find out which action is the culprit, and you
6723 were again too lazy to give <link linkend="contact">feedback</link>, so
6724 you just used the <literal>fragile</literal> alias on the site, and
6725 -- <emphasis>whoa!</emphasis> -- it worked. The <literal>fragile</literal>
6726 aliases disables those actions that are most likely to break a site. Also,
6727 good for testing purposes to see if it is <application>Privoxy</application>
6728 that is causing the problem or not. We later find other regular sites
6729 that misbehave, and add those to our personalized list of troublemakers:
6737 .mybank.com</screen>
6741 You like the <quote>fun</quote> text replacements in <filename>default.filter</filename>,
6742 but it is disabled in the distributed actions file.
6743 So you'd like to turn it on in your private,
6744 update-safe config, once and for all:
6749 { +<link linkend="filter-fun">filter{fun}</link> }
6750 / # For ALL sites!</screen>
6754 Note that the above is not really a good idea: There are exceptions
6755 to the filters in <filename>default.action</filename> for things that
6756 really shouldn't be filtered, like code on CVS->Web interfaces. Since
6757 <filename>user.action</filename> has the last word, these exceptions
6758 won't be valid for the <quote>fun</quote> filtering specified here.
6762 You might also worry about how your favourite free websites are
6763 funded, and find that they rely on displaying banner advertisements
6764 to survive. So you might want to specifically allow banners for those
6765 sites that you feel provide value to you:
6777 Note that <literal>allow-ads</literal> has been aliased to
6778 <literal>-<link linkend="block">block</link></literal>,
6779 <literal>-<link linkend="filter-banners-by-size">filter{banners-by-size}</link></literal>, and
6780 <literal>-<link linkend="filter-banners-by-link">filter{banners-by-link}</link></literal> above.
6784 Invoke another alias here to force an over-ride of the MIME type <literal>
6785 application/x-sh</literal> which typically would open a download type
6786 dialog. In my case, I want to look at the shell script, and then I can save
6787 it should I choose to.
6797 <filename>user.action</filename> is generally the best place to define
6798 exceptions and additions to the default policies of
6799 <filename>default.action</filename>. Some actions are safe to have their
6800 default policies set here though. So let's set a default policy to have a
6801 <quote>blank</quote> image as opposed to the checkerboard pattern for
6802 <emphasis>ALL</emphasis> sites. <quote>/</quote> of course matches all URL
6808 { +<link linkend="set-image-blocker">set-image-blocker{blank}</link> }
6809 / # ALL sites</screen>
6815 <!-- ~ End section ~ -->
6819 <!-- ~ End section ~ -->
6821 <!-- ~~~~~~~~ New section Header ~~~~~~~~~ -->
6823 <sect1 id="filter-file">
6824 <title>Filter Files</title>
6827 On-the-fly text substitutions need
6828 to be defined in a <quote>filter file</quote>. Once defined, they
6829 can then be invoked as an <quote>action</quote>.
6833 &my-app; supports three different filter actions:
6834 <literal><link linkend="filter">filter</link></literal> to
6835 rewrite the content that is send to the client,
6836 <literal><link linkend="client-header-filter">client-header-filter</link></literal>
6837 to rewrite headers that are send by the client, and
6838 <literal><link linkend="server-header-filter">server-header-filter</link></literal>
6839 to rewrite headers that are send by the server.
6843 &my-app; also supports two tagger actions:
6844 <literal><link linkend="client-header-tagger">client-header-tagger</link></literal>
6846 <literal><link linkend="server-header-tagger">server-header-tagger</link></literal>.
6847 Taggers and filters use the same syntax in the filter files, the difference
6848 is that taggers don't modify the text they are filtering, but use a rewritten
6849 version of the filtered text as tag. The tags can then be used to change the
6850 applying actions through sections with <link linkend="tag-pattern">tag-patterns</link>.
6855 Multiple filter files can be defined through the <literal> <link
6856 linkend="filterfile">filterfile</link></literal> config directive. The filters
6857 as supplied by the developers are located in
6858 <filename>default.filter</filename>. It is recommended that any locally
6859 defined or modified filters go in a separately defined file such as
6860 <filename>user.filter</filename>.
6864 Common tasks for content filters are to eliminate common annoyances in
6865 HTML and JavaScript, such as pop-up windows,
6866 exit consoles, crippled windows without navigation tools, the
6867 infamous <BLINK> tag etc, to suppress images with certain
6868 width and height attributes (standard banner sizes or web-bugs),
6869 or just to have fun.
6873 Enabled content filters are applied to any content whose
6874 <quote>Content Type</quote> header is recognised as a sign
6875 of text-based content, with the exception of <literal>text/plain</literal>.
6876 Use the <link linkend="FORCE-TEXT-MODE">force-text-mode</link> action
6877 to also filter other content.
6881 Substitutions are made at the source level, so if you want to <quote>roll
6882 your own</quote> filters, you should first be familiar with HTML syntax,
6883 and, of course, regular expressions.
6887 Just like the <link linkend="actions-file">actions files</link>, the
6888 filter file is organized in sections, which are called <emphasis>filters</emphasis>
6889 here. Each filter consists of a heading line, that starts with one of the
6890 <emphasis>keywords</emphasis> <literal>FILTER:</literal>,
6891 <literal>CLIENT-HEADER-FILTER:</literal> or <literal>SERVER-HEADER-FILTER:</literal>
6892 followed by the filter's <emphasis>name</emphasis>, and a short (one line)
6893 <emphasis>description</emphasis> of what it does. Below that line
6894 come the <emphasis>jobs</emphasis>, i.e. lines that define the actual
6895 text substitutions. By convention, the name of a filter
6896 should describe what the filter <emphasis>eliminates</emphasis>. The
6897 comment is used in the <ulink url="http://config.privoxy.org/">web-based
6898 user interface</ulink>.
6902 Once a filter called <replaceable>name</replaceable> has been defined
6903 in the filter file, it can be invoked by using an action of the form
6904 +<literal><link linkend="filter">filter</link>{<replaceable>name</replaceable>}</literal>
6905 in any <link linkend="actions-file">actions file</link>.
6909 Filter definitions start with a header line that contains the filter
6910 type, the filter name and the filter description.
6911 A content filter header line for a filter called <quote>foo</quote> could look
6916 <screen>FILTER: foo Replace all "foo" with "bar"</screen>
6920 Below that line, and up to the next header line, come the jobs that
6921 define what text replacements the filter executes. They are specified
6922 in a syntax that imitates <ulink url="http://www.perl.org/">Perl</ulink>'s
6923 <literal>s///</literal> operator. If you are familiar with Perl, you
6924 will find this to be quite intuitive, and may want to look at the
6925 PCRS documentation for the subtle differences to Perl behaviour. Most
6926 notably, the non-standard option letter <literal>U</literal> is supported,
6927 which turns the default to ungreedy matching.
6932 <ulink url="http://en.wikipedia.org/wiki/Regular_expressions"><quote>Regular
6933 Expressions</quote></ulink>, you might want to take a look at
6934 the <link linkend="regex">Appendix on regular expressions</link>, and
6935 see the <ulink url="http://perldoc.perl.org/perlre.html">Perl
6937 <ulink url="http://perldoc.perl.org/perlop.html">the
6938 <literal>s///</literal> operator's syntax</ulink> and <ulink
6939 url="http://perldoc.perl.org/perlre.html">Perl-style regular
6940 expressions</ulink> in general.
6941 The below examples might also help to get you started.
6945 <!-- ~~~~~~~~ New section Header ~~~~~~~~~ -->
6947 <sect2><title>Filter File Tutorial</title>
6949 Now, let's complete our <quote>foo</quote> content filter. We have already defined
6950 the heading, but the jobs are still missing. Since all it does is to replace
6951 <quote>foo</quote> with <quote>bar</quote>, there is only one (trivial) job
6956 <screen>s/foo/bar/</screen>
6960 But wait! Didn't the comment say that <emphasis>all</emphasis> occurrences
6961 of <quote>foo</quote> should be replaced? Our current job will only take
6962 care of the first <quote>foo</quote> on each page. For global substitution,
6963 we'll need to add the <literal>g</literal> option:
6967 <screen>s/foo/bar/g</screen>
6971 Our complete filter now looks like this:
6974 <screen>FILTER: foo Replace all "foo" with "bar"
6975 s/foo/bar/g</screen>
6979 Let's look at some real filters for more interesting examples. Here you see
6980 a filter that protects against some common annoyances that arise from JavaScript
6981 abuse. Let's look at its jobs one after the other:
6987 FILTER: js-annoyances Get rid of particularly annoying JavaScript abuse
6989 # Get rid of JavaScript referrer tracking. Test page: http://www.randomoddness.com/untitled.htm
6991 s|(<script.*)document\.referrer(.*</script>)|$1"Not Your Business!"$2|Usg</screen>
6995 Following the header line and a comment, you see the job. Note that it uses
6996 <literal>|</literal> as the delimiter instead of <literal>/</literal>, because
6997 the pattern contains a forward slash, which would otherwise have to be escaped
6998 by a backslash (<literal>\</literal>).
7002 Now, let's examine the pattern: it starts with the text <literal><script.*</literal>
7003 enclosed in parentheses. Since the dot matches any character, and <literal>*</literal>
7004 means: <quote>Match an arbitrary number of the element left of myself</quote>, this
7005 matches <quote><script</quote>, followed by <emphasis>any</emphasis> text, i.e.
7006 it matches the whole page, from the start of the first <script> tag.
7010 That's more than we want, but the pattern continues: <literal>document\.referrer</literal>
7011 matches only the exact string <quote>document.referrer</quote>. The dot needed to
7012 be <emphasis>escaped</emphasis>, i.e. preceded by a backslash, to take away its
7013 special meaning as a joker, and make it just a regular dot. So far, the meaning is:
7014 Match from the start of the first <script> tag in a the page, up to, and including,
7015 the text <quote>document.referrer</quote>, if <emphasis>both</emphasis> are present
7016 in the page (and appear in that order).
7020 But there's still more pattern to go. The next element, again enclosed in parentheses,
7021 is <literal>.*</script></literal>. You already know what <literal>.*</literal>
7022 means, so the whole pattern translates to: Match from the start of the first <script>
7023 tag in a page to the end of the last <script> tag, provided that the text
7024 <quote>document.referrer</quote> appears somewhere in between.
7028 This is still not the whole story, since we have ignored the options and the parentheses:
7029 The portions of the page matched by sub-patterns that are enclosed in parentheses, will be
7030 remembered and be available through the variables <literal>$1, $2, ...</literal> in
7031 the substitute. The <literal>U</literal> option switches to ungreedy matching, which means
7032 that the first <literal>.*</literal> in the pattern will only <quote>eat up</quote> all
7033 text in between <quote><script</quote> and the <emphasis>first</emphasis> occurrence
7034 of <quote>document.referrer</quote>, and that the second <literal>.*</literal> will
7035 only span the text up to the <emphasis>first</emphasis> <quote></script></quote>
7036 tag. Furthermore, the <literal>s</literal> option says that the match may span
7037 multiple lines in the page, and the <literal>g</literal> option again means that the
7038 substitution is global.
7042 So, to summarize, the pattern means: Match all scripts that contain the text
7043 <quote>document.referrer</quote>. Remember the parts of the script from
7044 (and including) the start tag up to (and excluding) the string
7045 <quote>document.referrer</quote> as <literal>$1</literal>, and the part following
7046 that string, up to and including the closing tag, as <literal>$2</literal>.
7050 Now the pattern is deciphered, but wasn't this about substituting things? So
7051 lets look at the substitute: <literal>$1"Not Your Business!"$2</literal> is
7052 easy to read: The text remembered as <literal>$1</literal>, followed by
7053 <literal>"Not Your Business!"</literal> (<emphasis>including</emphasis>
7054 the quotation marks!), followed by the text remembered as <literal>$2</literal>.
7055 This produces an exact copy of the original string, with the middle part
7056 (the <quote>document.referrer</quote>) replaced by <literal>"Not Your
7057 Business!"</literal>.
7061 The whole job now reads: Replace <quote>document.referrer</quote> by
7062 <literal>"Not Your Business!"</literal> wherever it appears inside a
7063 <script> tag. Note that this job won't break JavaScript syntax,
7064 since both the original and the replacement are syntactically valid
7065 string objects. The script just won't have access to the referrer
7066 information anymore.
7070 We'll show you two other jobs from the JavaScript taming department, but
7071 this time only point out the constructs of special interest:
7076 # The status bar is for displaying link targets, not pointless blahblah
7078 s/window\.status\s*=\s*(['"]).*?\1/dUmMy=1/ig</screen>
7082 <literal>\s</literal> stands for whitespace characters (space, tab, newline,
7083 carriage return, form feed), so that <literal>\s*</literal> means: <quote>zero
7084 or more whitespace</quote>. The <literal>?</literal> in <literal>.*?</literal>
7085 makes this matching of arbitrary text ungreedy. (Note that the <literal>U</literal>
7086 option is not set). The <literal>['"]</literal> construct means: <quote>a single
7087 <emphasis>or</emphasis> a double quote</quote>. Finally, <literal>\1</literal> is
7088 a back-reference to the first parenthesis just like <literal>$1</literal> above,
7089 with the difference that in the <emphasis>pattern</emphasis>, a backslash indicates
7090 a back-reference, whereas in the <emphasis>substitute</emphasis>, it's the dollar.
7094 So what does this job do? It replaces assignments of single- or double-quoted
7095 strings to the <quote>window.status</quote> object with a dummy assignment
7096 (using a variable name that is hopefully odd enough not to conflict with
7097 real variables in scripts). Thus, it catches many cases where e.g. pointless
7098 descriptions are displayed in the status bar instead of the link target when
7099 you move your mouse over links.
7104 # Kill OnUnload popups. Yummy. Test: http://www.zdnet.com/zdsubs/yahoo/tree/yfs.html
7106 s/(<body [^>]*)onunload(.*>)/$1never$2/iU</screen>
7111 <ulink url="http://www.w3.org/TR/2000/REC-DOM-Level-2-Events-20001113/events.html#Events-eventgroupings-htmlevents">OnUnload
7112 event binding</ulink> in the HTML DOM was a <emphasis>CRIME</emphasis>.
7113 When I close a browser window, I want it to close and die. Basta.
7114 This job replaces the <quote>onunload</quote> attribute in
7115 <quote><body></quote> tags with the dummy word <literal>never</literal>.
7116 Note that the <literal>i</literal> option makes the pattern matching
7117 case-insensitive. Also note that ungreedy matching alone doesn't always guarantee
7118 a minimal match: In the first parenthesis, we had to use <literal>[^>]*</literal>
7119 instead of <literal>.*</literal> to prevent the match from exceeding the
7120 <body> tag if it doesn't contain <quote>OnUnload</quote>, but the page's
7125 The last example is from the fun department:
7130 FILTER: fun Fun text replacements
7132 # Spice the daily news:
7134 s/microsoft(?!\.com)/MicroSuck/ig</screen>
7138 Note the <literal>(?!\.com)</literal> part (a so-called negative lookahead)
7139 in the job's pattern, which means: Don't match, if the string
7140 <quote>.com</quote> appears directly following <quote>microsoft</quote>
7141 in the page. This prevents links to microsoft.com from being trashed, while
7142 still replacing the word everywhere else.
7147 # Buzzword Bingo (example for extended regex syntax)
7149 s* industry[ -]leading \
7151 | customer[ -]focused \
7152 | market[ -]driven \
7153 | award[ -]winning # Comments are OK, too! \
7154 | high[ -]performance \
7155 | solutions[ -]based \
7159 *<font color="red"><b>BINGO!</b></font> \
7164 The <literal>x</literal> option in this job turns on extended syntax, and allows for
7165 e.g. the liberal use of (non-interpreted!) whitespace for nicer formatting.
7173 <!-- ~~~~~~~~ New section Header ~~~~~~~~~ -->
7175 <sect2 id="predefined-filters"><title>The Pre-defined Filters</title>
7179 Note each filter is also listed in the +filter action section above. Please
7180 keep these listings in sync.
7185 The distribution <filename>default.filter</filename> file contains a selection of
7186 pre-defined filters for your convenience:
7191 <term><emphasis>js-annoyances</emphasis></term>
7194 The purpose of this filter is to get rid of particularly annoying JavaScript abuse.
7199 replaces JavaScript references to the browser's referrer information
7200 with the string "Not Your Business!". This compliments the <literal><link
7201 linkend="hide-referrer">hide-referrer</link></literal> action on the content level.
7206 removes the bindings to the DOM's
7207 <ulink url="http://www.w3.org/TR/2000/REC-DOM-Level-2-Events-20001113/events.html#Events-eventgroupings-htmlevents">unload
7208 event</ulink> which we feel has no right to exist and is responsible for most <quote>exit consoles</quote>, i.e.
7209 nasty windows that pop up when you close another one.
7214 removes code that causes new windows to be opened with undesired properties, such as being
7215 full-screen, non-resizeable, without location, status or menu bar etc.
7221 Use with caution. This is an aggressive filter, and can break sites that
7222 rely heavily on JavaScript.
7228 <term><emphasis>js-events</emphasis></term>
7231 This is a very radical measure. It removes virtually all JavaScript event bindings, which
7232 means that scripts can not react to user actions such as mouse movements or clicks, window
7233 resizing etc, anymore. Use with caution!
7236 We <emphasis>strongly discourage</emphasis> using this filter as a default since it breaks
7237 many legitimate scripts. It is meant for use only on extra-nasty sites (should you really
7244 <term><emphasis>html-annoyances</emphasis></term>
7247 This filter will undo many common instances of HTML based abuse.
7250 The <literal>BLINK</literal> and <literal>MARQUEE</literal> tags
7251 are neutralized (yeah baby!), and browser windows will be created as
7252 resizeable (as of course they should be!), and will have location,
7253 scroll and menu bars -- even if specified otherwise.
7259 <term><emphasis>content-cookies</emphasis></term>
7262 Most cookies are set in the HTTP dialog, where they can be intercepted
7264 <literal><link linkend="crunch-incoming-cookies">crunch-incoming-cookies</link></literal>
7265 and <literal><link linkend="crunch-outgoing-cookies">crunch-outgoing-cookies</link></literal>
7266 actions. But web sites increasingly make use of HTML meta tags and JavaScript
7267 to sneak cookies to the browser on the content level.
7270 This filter disables most HTML and JavaScript code that reads or sets
7271 cookies. It cannot detect all clever uses of these types of code, so it
7272 should not be relied on as an absolute fix. Use it wherever you would also
7273 use the cookie crunch actions.
7279 <term><emphasis>refresh tags</emphasis></term>
7282 Disable any refresh tags if the interval is greater than nine seconds (so
7283 that redirections done via refresh tags are not destroyed). This is useful
7284 for dial-on-demand setups, or for those who find this HTML feature
7291 <term><emphasis>unsolicited-popups</emphasis></term>
7294 This filter attempts to prevent only <quote>unsolicited</quote> pop-up
7295 windows from opening, yet still allow pop-up windows that the user
7296 has explicitly chosen to open. It was added in version 3.0.1,
7297 as an improvement over earlier such filters.
7300 Technical note: The filter works by redefining the window.open JavaScript
7301 function to a dummy function, <literal>PrivoxyWindowOpen()</literal>,
7302 during the loading and rendering phase of each HTML page access, and
7303 restoring the function afterward.
7306 This is recommended only for browsers that cannot perform this function
7307 reliably themselves. And be aware that some sites require such windows
7308 in order to function normally. Use with caution.
7314 <term><emphasis>all-popups</emphasis></term>
7317 Attempt to prevent <emphasis>all</emphasis> pop-up windows from opening.
7318 Note this should be used with even more discretion than the above, since
7319 it is more likely to break some sites that require pop-ups for normal
7320 usage. Use with caution.
7326 <term><emphasis>img-reorder</emphasis></term>
7329 This is a helper filter that has no value if used alone. It makes the
7330 <literal>banners-by-size</literal> and <literal>banners-by-link</literal>
7331 (see below) filters more effective and should be enabled together with them.
7337 <term><emphasis>banners-by-size</emphasis></term>
7340 This filter removes image tags purely based on what size they are. Fortunately
7341 for us, many ads and banner images tend to conform to certain standardized
7342 sizes, which makes this filter quite effective for ad stripping purposes.
7345 Occasionally this filter will cause false positives on images that are not ads,
7346 but just happen to be of one of the standard banner sizes.
7349 Recommended only for those who require extreme ad blocking. The default
7350 block rules should catch 95+% of all ads <emphasis>without</emphasis> this filter enabled.
7356 <term><emphasis>banners-by-link</emphasis></term>
7359 This is an experimental filter that attempts to kill any banners if
7360 their URLs seem to point to known or suspected click trackers. It is currently
7361 not of much value and is not recommended for use by default.
7367 <term><emphasis>webbugs</emphasis></term>
7370 Webbugs are small, invisible images (technically 1X1 GIF images), that
7371 are used to track users across websites, and collect information on them.
7372 As an HTML page is loaded by the browser, an embedded image tag causes the
7373 browser to contact a third-party site, disclosing the tracking information
7374 through the requested URL and/or cookies for that third-party domain, without
7375 the user ever becoming aware of the interaction with the third-party site.
7376 HTML-ized spam also uses a similar technique to verify email addresses.
7379 This filter removes the HTML code that loads such <quote>webbugs</quote>.
7385 <term><emphasis>tiny-textforms</emphasis></term>
7388 A rather special-purpose filter that can be used to enlarge textareas (those
7389 multi-line text boxes in web forms) and turn off hard word wrap in them.
7390 It was written for the sourceforge.net tracker system where such boxes are
7391 a nuisance, but it can be handy on other sites, too.
7394 It is not recommended to use this filter as a default.
7400 <term><emphasis>jumping-windows</emphasis></term>
7403 Many consider windows that move, or resize themselves to be abusive. This filter
7404 neutralizes the related JavaScript code. Note that some sites might not display
7405 or behave as intended when using this filter. Use with caution.
7411 <term><emphasis>frameset-borders</emphasis></term>
7414 Some web designers seem to assume that everyone in the world will view their
7415 web sites using the same browser brand and version, screen resolution etc,
7416 because only that assumption could explain why they'd use static frame sizes,
7417 yet prevent their frames from being resized by the user, should they be too
7418 small to show their whole content.
7421 This filter removes the related HTML code. It should only be applied to sites
7428 <term><emphasis>demoronizer</emphasis></term>
7431 Many Microsoft products that generate HTML use non-standard extensions (read:
7432 violations) of the ISO 8859-1 aka Latin-1 character set. This can cause those
7433 HTML documents to display with errors on standard-compliant platforms.
7436 This filter translates the MS-only characters into Latin-1 equivalents.
7437 It is not necessary when using MS products, and will cause corruption of
7438 all documents that use 8-bit character sets other than Latin-1. It's mostly
7439 worthwhile for Europeans on non-MS platforms, if weird garbage characters
7440 sometimes appear on some pages, or user agents that don't correct for this on
7443 My version of Mozilla (ancient) shows litte square boxes for quote
7444 characters, and apostrophes on moronized pages. So many pages have this, I
7445 can read them fine now. HB 08/27/06
7452 <term><emphasis>shockwave-flash</emphasis></term>
7455 A filter for shockwave haters. As the name suggests, this filter strips code
7456 out of web pages that is used to embed shockwave flash objects.
7464 <term><emphasis>quicktime-kioskmode</emphasis></term>
7467 Change HTML code that embeds Quicktime objects so that kioskmode, which
7468 prevents saving, is disabled.
7474 <term><emphasis>fun</emphasis></term>
7477 Text replacements for subversive browsing fun. Make fun of your favorite
7478 Monopolist or play buzzword bingo.
7484 <term><emphasis>crude-parental</emphasis></term>
7487 A demonstration-only filter that shows how <application>Privoxy</application>
7488 can be used to delete web content on a keyword basis.
7494 <term><emphasis>ie-exploits</emphasis></term>
7497 An experimental collection of text replacements to disable malicious HTML and JavaScript
7498 code that exploits known security holes in Internet Explorer.
7501 Presently, it only protects against Nimda and a cross-site scripting bug, and
7502 would need active maintenance to provide more substantial protection.
7508 <term><emphasis>site-specifics</emphasis></term>
7511 Some web sites have very specific problems, the cure for which doesn't apply
7512 anywhere else, or could even cause damage on other sites.
7515 This is a collection of such site-specific cures which should only be applied
7516 to the sites they were intended for, which is what the supplied
7517 <filename>default.action</filename> file does. Users shouldn't need to change
7518 anything regarding this filter.
7524 <term><emphasis>google</emphasis></term>
7527 A CSS based block for Google text ads. Also removes a width limitation
7528 and the toolbar advertisement.
7534 <term><emphasis>yahoo</emphasis></term>
7537 Another CSS based block, this time for Yahoo text ads. And removes
7538 a width limitation as well.
7544 <term><emphasis>msn</emphasis></term>
7547 Another CSS based block, this time for MSN text ads. And removes
7548 tracking URLs, as well as a width limitation.
7554 <term><emphasis>blogspot</emphasis></term>
7557 Cleans up some Blogspot blogs. Read the fine print before using this one!
7560 This filter also intentionally removes some navigation stuff and sets the
7561 page width to 100%. As a result, some rounded <quote>corners</quote> would
7562 appear to early or not at all and as fixing this would require a browser
7563 that understands background-size (CSS3), they are removed instead.
7569 <term><emphasis>xml-to-html</emphasis></term>
7572 Server-header filter to change the Content-Type from xml to html.
7578 <term><emphasis>html-to-xml</emphasis></term>
7581 Server-header filter to change the Content-Type from html to xml.
7587 <term><emphasis>no-ping</emphasis></term>
7590 Removes the non-standard <literal>ping</literal> attribute from
7591 anchor and area HTML tags.
7597 <term><emphasis>hide-tor-exit-notation</emphasis></term>
7600 Client-header filter to remove the <command>Tor</command> exit node notation
7601 found in Host and Referer headers.
7604 If &my-app; and <command>Tor</command> are chained and &my-app;
7605 is configured to use socks4a, one can use <quote>http://www.example.org.foobar.exit/</quote>
7606 to access the host <quote>www.example.org</quote> through the
7607 <command>Tor</command> exit node <quote>foobar</quote>.
7610 As the HTTP client isn't aware of this notation, it treats the
7611 whole string <quote>www.example.org.foobar.exit</quote> as host and uses it
7612 for the <quote>Host</quote> and <quote>Referer</quote> headers. From the
7613 server's point of view the resulting headers are invalid and can cause problems.
7616 An invalid <quote>Referer</quote> header can trigger <quote>hot-linking</quote>
7617 protections, an invalid <quote>Host</quote> header will make it impossible for
7618 the server to find the right vhost (several domains hosted on the same IP address).
7621 This client-header filter removes the <quote>foo.exit</quote> part in those headers
7622 to prevent the mentioned problems. Note that it only modifies
7623 the HTTP headers, it doesn't make it impossible for the server
7624 to detect your <command>Tor</command> exit node based on the IP address
7625 the request is coming from.
7632 <term><emphasis> </emphasis></term>
7646 <!-- ~ End section ~ -->
7650 <!-- ~~~~~ New section ~~~~~ -->
7652 <sect1 id="templates">
7653 <title>Privoxy's Template Files</title>
7655 All <application>Privoxy</application> built-in pages, i.e. error pages such as the
7656 <ulink url="http://show-the-404-error.page"><quote>404 - No Such Domain</quote>
7657 error page</ulink>, the <ulink
7658 url="http://ads.bannerserver.example.com/nasty-ads/sponsor.html"><quote>BLOCKED</quote>
7660 and all pages of its <ulink url="http://config.privoxy.org/">web-based
7661 user interface</ulink>, are generated from <emphasis>templates</emphasis>.
7662 (<application>Privoxy</application> must be running for the above links to work as
7667 These templates are stored in a subdirectory of the <link linkend="confdir">configuration
7668 directory</link> called <filename>templates</filename>. On Unixish platforms,
7670 <ulink url="file:///etc/privoxy/templates/"><filename>/etc/privoxy/templates/</filename></ulink>.
7674 The templates are basically normal HTML files, but with place-holders (called symbols
7675 or exports), which <application>Privoxy</application> fills at run time. It
7676 is possible to edit the templates with a normal text editor, should you want
7677 to customize them. (<emphasis>Not recommended for the casual
7678 user</emphasis>). Should you create your own custom templates, you should use
7679 the <filename>config</filename> setting <link linkend="templdir">templdir</link>
7680 to specify an alternate location, so your templates do not get overwritten
7684 Note that just like in configuration files, lines starting
7685 with <literal>#</literal> are ignored when the templates are filled in.
7689 The place-holders are of the form <literal>@name@</literal>, and you will
7690 find a list of available symbols, which vary from template to template,
7691 in the comments at the start of each file. Note that these comments are not
7692 always accurate, and that it's probably best to look at the existing HTML
7693 code to find out which symbols are supported and what they are filled in with.
7697 A special application of this substitution mechanism is to make whole
7698 blocks of HTML code disappear when a specific symbol is set. We use this
7699 for many purposes, one of them being to include the beta warning in all
7700 our user interface (CGI) pages when <application>Privoxy</application>
7701 is in an alpha or beta development stage:
7706 <!-- @if-unstable-start -->
7708 ... beta warning HTML code goes here ...
7710 <!-- if-unstable-end@ --></screen>
7714 If the "unstable" symbol is set, everything in between and including
7715 <literal>@if-unstable-start</literal> and <literal>if-unstable-end@</literal>
7716 will disappear, leaving nothing but an empty comment:
7720 <screen><!-- --></screen>
7724 There's also an if-then-else construct and an <literal>#include</literal>
7725 mechanism, but you'll sure find out if you are inclined to edit the
7730 All templates refer to a style located at
7731 <ulink url="http://config.privoxy.org/send-stylesheet"><literal>http://config.privoxy.org/send-stylesheet</literal></ulink>.
7732 This is, of course, locally served by <application>Privoxy</application>
7733 and the source for it can be found and edited in the
7734 <filename>cgi-style.css</filename> template.
7739 <!-- ~ End section ~ -->
7743 <!-- ~~~~~ New section ~~~~~ -->
7745 <sect1 id="contact"><title>Contacting the Developers, Bug Reporting and Feature
7748 <!-- Include contacting.sgml boilerplate: -->
7750 <!-- end boilerplate -->
7754 <!-- ~ End section ~ -->
7757 <!-- ~~~~~ New section ~~~~~ -->
7758 <sect1 id="copyright"><title>Privoxy Copyright, License and History</title>
7760 <!-- Include copyright.sgml: -->
7762 <!-- end copyright -->
7764 <!-- ~~~~~ New section ~~~~~ -->
7765 <sect2><title>License</title>
7766 <!-- Include copyright.sgml: -->
7768 <!-- end copyright -->
7770 <!-- ~ End section ~ -->
7773 <!-- ~~~~~ New section ~~~~~ -->
7775 <sect2 id="history"><title>History</title>
7776 <!-- Include history.sgml: -->
7778 <!-- end history -->
7781 <sect2 id="authors"><title>Authors</title>
7782 <!-- Include p-authors.sgml: -->
7784 <!-- end authors -->
7789 <!-- ~ End section ~ -->
7792 <!-- ~~~~~ New section ~~~~~ -->
7793 <sect1 id="seealso"><title>See Also</title>
7794 <!-- Include seealso.sgml: -->
7796 <!-- end seealso -->
7801 <!-- ~~~~~ New section ~~~~~ -->
7802 <sect1 id="appendix"><title>Appendix</title>
7805 <!-- ~~~~~ New section ~~~~~ -->
7807 <title>Regular Expressions</title>
7809 <application>Privoxy</application> uses Perl-style <quote>regular
7810 expressions</quote> in its <link linkend="actions-file">actions
7811 files</link> and <link linkend="filter-file">filter file</link>,
7812 through the <ulink url="http://www.pcre.org/">PCRE</ulink> and
7815 <ulink url="http://www.oesterhelt.org/pcrs/">PCRS</ulink> libraries.
7817 <application>PCRS</application> libraries.
7821 If you are reading this, you probably don't understand what <quote>regular
7822 expressions</quote> are, or what they can do. So this will be a very brief
7823 introduction only. A full explanation would require a <ulink
7824 url="http://www.oreilly.com/catalog/regex/">book</ulink> ;-)
7828 Regular expressions provide a language to describe patterns that can be
7829 run against strings of characters (letter, numbers, etc), to see if they
7830 match the string or not. The patterns are themselves (sometimes complex)
7831 strings of literal characters, combined with wild-cards, and other special
7832 characters, called meta-characters. The <quote>meta-characters</quote> have
7833 special meanings and are used to build complex patterns to be matched against.
7834 Perl Compatible Regular Expressions are an especially convenient
7835 <quote>dialect</quote> of the regular expression language.
7839 To make a simple analogy, we do something similar when we use wild-card
7840 characters when listing files with the <command>dir</command> command in DOS.
7841 <literal>*.*</literal> matches all filenames. The <quote>special</quote>
7842 character here is the asterisk which matches any and all characters. We can be
7843 more specific and use <literal>?</literal> to match just individual
7844 characters. So <quote>dir file?.text</quote> would match
7845 <quote>file1.txt</quote>, <quote>file2.txt</quote>, etc. We are pattern
7846 matching, using a similar technique to <quote>regular expressions</quote>!
7850 Regular expressions do essentially the same thing, but are much, much more
7851 powerful. There are many more <quote>special characters</quote> and ways of
7852 building complex patterns however. Let's look at a few of the common ones,
7853 and then some examples:
7858 <emphasis>.</emphasis> - Matches any single character, e.g. <quote>a</quote>,
7859 <quote>A</quote>, <quote>4</quote>, <quote>:</quote>, or <quote>@</quote>.
7861 </simplelist></para>
7865 <emphasis>?</emphasis> - The preceding character or expression is matched ZERO or ONE
7868 </simplelist></para>
7872 <emphasis>+</emphasis> - The preceding character or expression is matched ONE or MORE
7875 </simplelist></para>
7879 <emphasis>*</emphasis> - The preceding character or expression is matched ZERO or MORE
7882 </simplelist></para>
7886 <emphasis>\</emphasis> - The <quote>escape</quote> character denotes that
7887 the following character should be taken literally. This is used where one of the
7888 special characters (e.g. <quote>.</quote>) needs to be taken literally and
7889 not as a special meta-character. Example: <quote>example\.com</quote>, makes
7890 sure the period is recognized only as a period (and not expanded to its
7891 meta-character meaning of any single character).
7893 </simplelist></para>
7897 <emphasis>[ ]</emphasis> - Characters enclosed in brackets will be matched if
7898 any of the enclosed characters are encountered. For instance, <quote>[0-9]</quote>
7899 matches any numeric digit (zero through nine). As an example, we can combine
7900 this with <quote>+</quote> to match any digit one of more times: <quote>[0-9]+</quote>.
7902 </simplelist></para>
7906 <emphasis>( )</emphasis> - parentheses are used to group a sub-expression,
7907 or multiple sub-expressions.
7909 </simplelist></para>
7913 <emphasis>|</emphasis> - The <quote>bar</quote> character works like an
7914 <quote>or</quote> conditional statement. A match is successful if the
7915 sub-expression on either side of <quote>|</quote> matches. As an example:
7916 <quote>/(this|that) example/</quote> uses grouping and the bar character
7917 and would match either <quote>this example</quote> or <quote>that
7918 example</quote>, and nothing else.
7920 </simplelist></para>
7923 These are just some of the ones you are likely to use when matching URLs with
7924 <application>Privoxy</application>, and is a long way from a definitive
7925 list. This is enough to get us started with a few simple examples which may
7926 be more illuminating:
7930 <emphasis><literal>/.*/banners/.*</literal></emphasis> - A simple example
7931 that uses the common combination of <quote>.</quote> and <quote>*</quote> to
7932 denote any character, zero or more times. In other words, any string at all.
7933 So we start with a literal forward slash, then our regular expression pattern
7934 (<quote>.*</quote>) another literal forward slash, the string
7935 <quote>banners</quote>, another forward slash, and lastly another
7936 <quote>.*</quote>. We are building
7937 a directory path here. This will match any file with the path that has a
7938 directory named <quote>banners</quote> in it. The <quote>.*</quote> matches
7939 any characters, and this could conceivably be more forward slashes, so it
7940 might expand into a much longer looking path. For example, this could match:
7941 <quote>/eye/hate/spammers/banners/annoy_me_please.gif</quote>, or just
7942 <quote>/banners/annoying.html</quote>, or almost an infinite number of other
7943 possible combinations, just so it has <quote>banners</quote> in the path
7948 And now something a little more complex:
7952 <emphasis><literal>/.*/adv((er)?ts?|ertis(ing|ements?))?/</literal></emphasis> -
7953 We have several literal forward slashes again (<quote>/</quote>), so we are
7954 building another expression that is a file path statement. We have another
7955 <quote>.*</quote>, so we are matching against any conceivable sub-path, just so
7956 it matches our expression. The only true literal that <emphasis>must
7957 match</emphasis> our pattern is <application>adv</application>, together with
7958 the forward slashes. What comes after the <quote>adv</quote> string is the
7963 Remember the <quote>?</quote> means the preceding expression (either a
7964 literal character or anything grouped with <quote>(...)</quote> in this case)
7965 can exist or not, since this means either zero or one match. So
7966 <quote>((er)?ts?|ertis(ing|ements?))</quote> is optional, as are the
7967 individual sub-expressions: <quote>(er)</quote>,
7968 <quote>(ing|ements?)</quote>, and the <quote>s</quote>. The <quote>|</quote>
7969 means <quote>or</quote>. We have two of those. For instance,
7970 <quote>(ing|ements?)</quote>, can expand to match either <quote>ing</quote>
7971 <emphasis>OR</emphasis> <quote>ements?</quote>. What is being done here, is an
7972 attempt at matching as many variations of <quote>advertisement</quote>, and
7973 similar, as possible. So this would expand to match just <quote>adv</quote>,
7974 or <quote>advert</quote>, or <quote>adverts</quote>, or
7975 <quote>advertising</quote>, or <quote>advertisement</quote>, or
7976 <quote>advertisements</quote>. You get the idea. But it would not match
7977 <quote>advertizements</quote> (with a <quote>z</quote>). We could fix that by
7978 changing our regular expression to:
7979 <quote>/.*/adv((er)?ts?|erti(s|z)(ing|ements?))?/</quote>, which would then match
7984 <emphasis><literal>/.*/advert[0-9]+\.(gif|jpe?g)</literal></emphasis> - Again
7985 another path statement with forward slashes. Anything in the square brackets
7986 <quote>[ ]</quote> can be matched. This is using <quote>0-9</quote> as a
7987 shorthand expression to mean any digit one through nine. It is the same as
7988 saying <quote>0123456789</quote>. So any digit matches. The <quote>+</quote>
7989 means one or more of the preceding expression must be included. The preceding
7990 expression here is what is in the square brackets -- in this case, any digit
7991 one through nine. Then, at the end, we have a grouping: <quote>(gif|jpe?g)</quote>.
7992 This includes a <quote>|</quote>, so this needs to match the expression on
7993 either side of that bar character also. A simple <quote>gif</quote> on one side, and the other
7994 side will in turn match either <quote>jpeg</quote> or <quote>jpg</quote>,
7995 since the <quote>?</quote> means the letter <quote>e</quote> is optional and
7996 can be matched once or not at all. So we are building an expression here to
7997 match image GIF or JPEG type image file. It must include the literal
7998 string <quote>advert</quote>, then one or more digits, and a <quote>.</quote>
7999 (which is now a literal, and not a special character, since it is escaped
8000 with <quote>\</quote>), and lastly either <quote>gif</quote>, or
8001 <quote>jpeg</quote>, or <quote>jpg</quote>. Some possible matches would
8002 include: <quote>//advert1.jpg</quote>,
8003 <quote>/nasty/ads/advert1234.gif</quote>,
8004 <quote>/banners/from/hell/advert99.jpg</quote>. It would not match
8005 <quote>advert1.gif</quote> (no leading slash), or
8006 <quote>/adverts232.jpg</quote> (the expression does not include an
8007 <quote>s</quote>), or <quote>/advert1.jsp</quote> (<quote>jsp</quote> is not
8008 in the expression anywhere).
8012 We are barely scratching the surface of regular expressions here so that you
8013 can understand the default <application>Privoxy</application>
8014 configuration files, and maybe use this knowledge to customize your own
8015 installation. There is much, much more that can be done with regular
8016 expressions. Now that you know enough to get started, you can learn more on
8021 More reading on Perl Compatible Regular expressions:
8022 <ulink url="http://perldoc.perl.org/perlre.html">http://perldoc.perl.org/perlre.html</ulink>
8026 For information on regular expression based substitutions and their applications
8027 in filters, please see the <link linkend="filter-file">filter file tutorial</link>
8032 <!-- ~ End section ~ -->
8035 <!-- ~~~~~ New section ~~~~~ -->
8037 <title>Privoxy's Internal Pages</title>
8040 Since <application>Privoxy</application> proxies each requested
8041 web page, it is easy for <application>Privoxy</application> to
8042 trap certain special URLs. In this way, we can talk directly to
8043 <application>Privoxy</application>, and see how it is
8044 configured, see how our rules are being applied, change these
8045 rules and other configuration options, and even turn
8046 <application>Privoxy's</application> filtering off, all with
8052 The URLs listed below are the special ones that allow direct access
8053 to <application>Privoxy</application>. Of course,
8054 <application>Privoxy</application> must be running to access these. If
8055 not, you will get a friendly error message. Internet access is not
8068 <ulink url="http://config.privoxy.org/">http://config.privoxy.org/</ulink>
8072 There is a shortcut: <ulink url="http://p.p/">http://p.p/</ulink> (But it
8073 doesn't provide a fall-back to a real page, in case the request is not
8074 sent through <application>Privoxy</application>)
8080 Show information about the current configuration, including viewing and
8081 editing of actions files:
8085 <ulink url="http://config.privoxy.org/show-status">http://config.privoxy.org/show-status</ulink>
8092 Show the source code version numbers:
8096 <ulink url="http://config.privoxy.org/show-version">http://config.privoxy.org/show-version</ulink>
8103 Show the browser's request headers:
8107 <ulink url="http://config.privoxy.org/show-request">http://config.privoxy.org/show-request</ulink>
8114 Show which actions apply to a URL and why:
8118 <ulink url="http://config.privoxy.org/show-url-info">http://config.privoxy.org/show-url-info</ulink>
8125 Toggle Privoxy on or off. This feature can be turned off/on in the main
8126 <filename>config</filename> file. When toggled <quote>off</quote>, <quote>Privoxy</quote>
8127 continues to run, but only as a pass-through proxy, with no actions taking
8132 <ulink url="http://config.privoxy.org/toggle">http://config.privoxy.org/toggle</ulink>
8136 Short cuts. Turn off, then on:
8140 <ulink url="http://config.privoxy.org/toggle?set=disable">http://config.privoxy.org/toggle?set=disable</ulink>
8145 <ulink url="http://config.privoxy.org/toggle?set=enable">http://config.privoxy.org/toggle?set=enable</ulink>
8154 These may be bookmarked for quick reference. See next.
8158 <sect3 id="bookmarklets">
8159 <title>Bookmarklets</title>
8161 Below are some <quote>bookmarklets</quote> to allow you to easily access a
8162 <quote>mini</quote> version of some of <application>Privoxy's</application>
8163 special pages. They are designed for MS Internet Explorer, but should work
8164 equally well in Netscape, Mozilla, and other browsers which support
8165 JavaScript. They are designed to run directly from your bookmarks - not by
8166 clicking the links below (although that should work for testing).
8169 To save them, right-click the link and choose <quote>Add to Favorites</quote>
8170 (IE) or <quote>Add Bookmark</quote> (Netscape). You will get a warning that
8171 the bookmark <quote>may not be safe</quote> - just click OK. Then you can run the
8172 Bookmarklet directly from your favorites/bookmarks. For even faster access,
8173 you can put them on the <quote>Links</quote> bar (IE) or the <quote>Personal
8174 Toolbar</quote> (Netscape), and run them with a single click.
8183 url="javascript:void(window.open('http://config.privoxy.org/toggle?mini=y&set=enabled','ijbstatus','width=250,height=100,resizable=yes,scrollbars=no,toolbar=no,location=no,directories=no,status=no,menubar=no,copyhistory=no').focus());">Privoxy - Enable</ulink>
8190 url="javascript:void(window.open('http://config.privoxy.org/toggle?mini=y&set=disabled','ijbstatus','width=250,height=100,resizable=yes,scrollbars=no,toolbar=no,location=no,directories=no,status=no,menubar=no,copyhistory=no').focus());">Privoxy - Disable</ulink>
8197 url="javascript:void(window.open('http://config.privoxy.org/toggle?mini=y&set=toggle','ijbstatus','width=250,height=100,resizable=yes,scrollbars=no,toolbar=no,location=no,directories=no,status=no,menubar=no,copyhistory=no').focus());">Privoxy - Toggle Privoxy</ulink> (Toggles between enabled and disabled)
8204 url="javascript:void(window.open('http://config.privoxy.org/toggle?mini=y','ijbstatus','width=250,height=2,resizable=yes,scrollbars=no,toolbar=no,location=no,directories=no,status=no,menubar=no,copyhistory=no').focus());">Privoxy- View Status</ulink>
8210 <ulink url="javascript:w=Math.floor(screen.width/2);h=Math.floor(screen.height*0.9);void(window.open('http://www.privoxy.org/actions/index.php?url='+escape(location.href),'Feedback','screenx='+w+',width='+w+',height='+h+',scrollbars=yes,toolbar=no,location=no,directories=no,status=no,menubar=no,copyhistory=no').focus());">Privoxy - Submit Actions File Feedback</ulink>
8216 <ulink url="javascript:void(window.open('http://config.privoxy.org/show-url-info?url='+escape(location.href),'Why').focus());">Privoxy - Why?</ulink>
8223 Credit: The site which gave us the general idea for these bookmarklets is
8224 <ulink url="http://www.bookmarklets.com/">www.bookmarklets.com</ulink>. They
8225 have more information about bookmarklets.
8234 <!-- ~~~~~ New section ~~~~~ -->
8236 <title>Chain of Events</title>
8238 Let's take a quick look at how some of <application>Privoxy's</application>
8239 core features are triggered, and the ensuing sequence of events when a web
8240 page is requested by your browser:
8247 First, your web browser requests a web page. The browser knows to send
8248 the request to <application>Privoxy</application>, which will in turn,
8249 relay the request to the remote web server after passing the following
8255 <application>Privoxy</application> traps any request for its own internal CGI
8256 pages (e.g <ulink url="http://p.p/">http://p.p/</ulink>) and sends the CGI page back to the browser.
8261 Next, <application>Privoxy</application> checks to see if the URL
8263 linkend="BLOCK"><quote>+block</quote></link> patterns. If
8264 so, the URL is then blocked, and the remote web server will not be contacted.
8265 <link linkend="HANDLE-AS-IMAGE"><quote>+handle-as-image</quote></link>
8267 <link linkend="HANDLE-AS-EMPTY-DOCUMENT"><quote>+handle-as-empty-document</quote></link>
8268 are then checked, and if there is no match, an
8269 HTML <quote>BLOCKED</quote> page is sent back to the browser. Otherwise, if
8270 it does match, an image is returned for the former, and an empty text
8271 document for the latter. The type of image would depend on the setting of
8272 <link linkend="SET-IMAGE-BLOCKER"><quote>+set-image-blocker</quote></link>
8273 (blank, checkerboard pattern, or an HTTP redirect to an image elsewhere).
8278 Untrusted URLs are blocked. If URLs are being added to the
8279 <filename>trust</filename> file, then that is done.
8284 If the URL pattern matches the <link
8285 linkend="FAST-REDIRECTS"><quote>+fast-redirects</quote></link> action,
8286 it is then processed. Unwanted parts of the requested URL are stripped.
8291 Now the rest of the client browser's request headers are processed. If any
8292 of these match any of the relevant actions (e.g. <link
8293 linkend="HIDE-USER-AGENT"><quote>+hide-user-agent</quote></link>,
8294 etc.), headers are suppressed or forged as determined by these actions and
8300 Now the web server starts sending its response back (i.e. typically a web
8306 First, the server headers are read and processed to determine, among other
8307 things, the MIME type (document type) and encoding. The headers are then
8308 filtered as determined by the
8309 <link linkend="CRUNCH-INCOMING-COOKIES"><quote>+crunch-incoming-cookies</quote></link>,
8310 <link linkend="SESSION-COOKIES-ONLY"><quote>+session-cookies-only</quote></link>,
8311 and <link linkend="DOWNGRADE-HTTP-VERSION"><quote>+downgrade-http-version</quote></link>
8317 If the <link linkend="KILL-POPUPS"><quote>+kill-popups</quote></link>
8318 action applies, and it is an HTML or JavaScript document, the popup-code in the
8319 response is filtered on-the-fly as it is received.
8324 If any <link linkend="FILTER"><quote>+filter</quote></link> action
8326 linkend="DEANIMATE-GIFS"><quote>+deanimate-gifs</quote></link>
8327 action applies (and the document type fits the action), the rest of the page is
8328 read into memory (up to a configurable limit). Then the filter rules (from
8329 <filename>default.filter</filename> and any other filter files) are
8330 processed against the buffered content. Filters are applied in the order
8331 they are specified in one of the filter files. Animated GIFs, if present,
8332 are reduced to either the first or last frame, depending on the action
8333 setting.The entire page, which is now filtered, is then sent by
8334 <application>Privoxy</application> back to your browser.
8337 If neither a <link linkend="FILTER"><quote>+filter</quote></link> action
8339 linkend="DEANIMATE-GIFS"><quote>+deanimate-gifs</quote></link>
8340 matches, then <application>Privoxy</application> passes the raw data through
8341 to the client browser as it becomes available.
8346 As the browser receives the now (possibly filtered) page content, it
8347 reads and then requests any URLs that may be embedded within the page
8348 source, e.g. ad images, stylesheets, JavaScript, other HTML documents (e.g.
8349 frames), sounds, etc. For each of these objects, the browser issues a
8350 separate request (this is easily viewable in <application>Privoxy's</application>
8351 logs). And each such request is in turn processed just as above. Note that a
8352 complex web page will have many, many such embedded URLs. If these
8353 secondary requests are to a different server, then quite possibly a very
8354 differing set of actions is triggered.
8361 NOTE: This is somewhat of a simplistic overview of what happens with each URL
8362 request. For the sake of brevity and simplicity, we have focused on
8363 <application>Privoxy's</application> core features only.
8369 <!-- ~~~~~ New section ~~~~~ -->
8370 <sect2 id="actionsanat">
8371 <title>Troubleshooting: Anatomy of an Action</title>
8374 The way <application>Privoxy</application> applies
8375 <link linkend="ACTIONS">actions</link> and <link linkend="FILTER">filters</link>
8376 to any given URL can be complex, and not always so
8377 easy to understand what is happening. And sometimes we need to be able to
8378 <emphasis>see</emphasis> just what <application>Privoxy</application> is
8379 doing. Especially, if something <application>Privoxy</application> is doing
8380 is causing us a problem inadvertently. It can be a little daunting to look at
8381 the actions and filters files themselves, since they tend to be filled with
8382 <link linkend="regex">regular expressions</link> whose consequences are not
8387 One quick test to see if <application>Privoxy</application> is causing a problem
8388 or not, is to disable it temporarily. This should be the first troubleshooting
8389 step. See <link linkend="bookmarklets">the Bookmarklets</link> section on a quick
8390 and easy way to do this (be sure to flush caches afterward!). Looking at the
8391 logs is a good idea too. (Note that both the toggle feature and logging are
8392 enabled via <filename>config</filename> file settings, and may need to be
8393 turned <quote>on</quote>.)
8396 Another easy troubleshooting step to try is if you have done any
8397 customization of your installation, revert back to the installed
8398 defaults and see if that helps. There are times the developers get complaints
8399 about one thing or another, and the problem is more related to a customized
8400 configuration issue.
8404 <application>Privoxy</application> also provides the
8405 <ulink url="http://config.privoxy.org/show-url-info">http://config.privoxy.org/show-url-info</ulink>
8406 page that can show us very specifically how <application>actions</application>
8407 are being applied to any given URL. This is a big help for troubleshooting.
8411 First, enter one URL (or partial URL) at the prompt, and then
8412 <application>Privoxy</application> will tell us
8413 how the current configuration will handle it. This will not
8414 help with filtering effects (i.e. the <link
8415 linkend="FILTER"><quote>+filter</quote></link> action) from
8416 one of the filter files since this is handled very
8417 differently and not so easy to trap! It also will not tell you about any other
8418 URLs that may be embedded within the URL you are testing. For instance, images
8419 such as ads are expressed as URLs within the raw page source of HTML pages. So
8420 you will only get info for the actual URL that is pasted into the prompt area
8421 -- not any sub-URLs. If you want to know about embedded URLs like ads, you
8422 will have to dig those out of the HTML source. Use your browser's <quote>View
8423 Page Source</quote> option for this. Or right click on the ad, and grab the
8428 Let's try an example, <ulink url="http://google.com">google.com</ulink>,
8429 and look at it one section at a time in a sample configuration (your real
8430 configuration may vary):
8435 Matches for http://www.google.com:
8437 In file: default.action <guibutton>[ View ]</guibutton> <guibutton>[ Edit ]</guibutton>
8439 {+deanimate-gifs {last}
8440 +fast-redirects {check-decoded-url}
8441 +filter {refresh-tags}
8442 +filter {img-reorder}
8443 +filter {banners-by-size}
8445 +filter {jumping-windows}
8446 +filter {ie-exploits}
8447 +hide-forwarded-for-headers
8448 +hide-from-header {block}
8449 +hide-referrer {forge}
8450 +session-cookies-only
8451 +set-image-blocker {pattern}
8454 { -session-cookies-only }
8460 In file: user.action <guibutton>[ View ]</guibutton> <guibutton>[ Edit ]</guibutton>
8461 (no matches in this file)
8466 This is telling us how we have defined our
8467 <link linkend="ACTIONS"><quote>actions</quote></link>, and
8468 which ones match for our test case, <quote>google.com</quote>.
8469 Displayed is all the actions that are available to us. Remember,
8470 the <literal>+</literal> sign denotes <quote>on</quote>. <literal>-</literal>
8471 denotes <quote>off</quote>. So some are <quote>on</quote> here, but many
8472 are <quote>off</quote>. Each example we try may provide a slightly different
8473 end result, depending on our configuration directives.
8477 is for our <filename>default.action</filename> file. The large, multi-line
8478 listing, is how the actions are set to match for all URLs, i.e. our default
8479 settings. If you look at your <quote>actions</quote> file, this would be the
8480 section just below the <quote>aliases</quote> section near the top. This
8481 will apply to all URLs as signified by the single forward slash at the end
8482 of the listing -- <quote> / </quote>.
8486 But we have defined additional actions that would be exceptions to these general
8487 rules, and then we list specific URLs (or patterns) that these exceptions
8488 would apply to. Last match wins. Just below this then are two explicit
8489 matches for <quote>.google.com</quote>. The first is negating our previous
8490 cookie setting, which was for <link
8491 linkend="SESSION-COOKIES-ONLY"><quote>+session-cookies-only</quote></link>
8492 (i.e. not persistent). So we will allow persistent cookies for google, at
8493 least that is how it is in this example. The second turns
8494 <emphasis>off</emphasis> any <link
8495 linkend="FAST-REDIRECTS"><quote>+fast-redirects</quote></link>
8496 action, allowing this to take place unmolested. Note that there is a leading
8497 dot here -- <quote>.google.com</quote>. This will match any hosts and
8498 sub-domains, in the google.com domain also, such as
8499 <quote>www.google.com</quote> or <quote>mail.google.com</quote>. But it would not
8500 match <quote>www.google.de</quote>! So, apparently, we have these two actions
8501 defined as exceptions to the general rules at the top somewhere in the lower
8502 part of our <filename>default.action</filename> file, and
8503 <quote>google.com</quote> is referenced somewhere in these latter sections.
8507 Then, for our <filename>user.action</filename> file, we again have no hits.
8508 So there is nothing google-specific that we might have added to our own, local
8509 configuration. If there was, those actions would over-rule any actions from
8510 previously processed files, such as <filename>default.action</filename>.
8511 <filename>user.action</filename> typically has the last word. This is the
8512 best place to put hard and fast exceptions,
8516 And finally we pull it all together in the bottom section and summarize how
8517 <application>Privoxy</application> is applying all its <quote>actions</quote>
8518 to <quote>google.com</quote>:
8529 -client-header-filter{hide-tor-exit-notation}
8530 -content-type-overwrite
8531 -crunch-client-header
8532 -crunch-if-none-match
8533 -crunch-incoming-cookies
8534 -crunch-outgoing-cookies
8535 -crunch-server-header
8536 +deanimate-gifs {last}
8537 -downgrade-http-version
8540 -filter {content-cookies}
8541 -filter {all-popups}
8542 -filter {banners-by-link}
8543 -filter {tiny-textforms}
8544 -filter {frameset-borders}
8545 -filter {demoronizer}
8546 -filter {shockwave-flash}
8547 -filter {quicktime-kioskmode}
8549 -filter {crude-parental}
8550 -filter {site-specifics}
8551 -filter {js-annoyances}
8552 -filter {html-annoyances}
8553 +filter {refresh-tags}
8554 -filter {unsolicited-popups}
8555 +filter {img-reorder}
8556 +filter {banners-by-size}
8558 +filter {jumping-windows}
8559 +filter {ie-exploits}
8566 -handle-as-empty-document
8568 -hide-accept-language
8569 -hide-content-disposition
8570 +hide-forwarded-for-headers
8571 +hide-from-header {block}
8572 -hide-if-modified-since
8573 +hide-referrer {forge}
8578 -overwrite-last-modified
8579 -prevent-compression
8583 -server-header-filter{xml-to-html}
8584 -server-header-filter{html-to-xml}
8585 -session-cookies-only
8586 +set-image-blocker {pattern} </screen>
8590 Notice the only difference here to the previous listing, is to
8591 <quote>fast-redirects</quote> and <quote>session-cookies-only</quote>,
8592 which are activated specifically for this site in our configuration,
8593 and thus show in the <quote>Final Results</quote>.
8597 Now another example, <quote>ad.doubleclick.net</quote>:
8603 { +block{Domains starts with "ad"} }
8606 { +block{Domain contains "ad"} }
8609 { +block{Doubleclick banner server} +handle-as-image }
8610 .[a-vx-z]*.doubleclick.net
8615 We'll just show the interesting part here - the explicit matches. It is
8616 matched three different times. Two <quote>+block{}</quote> sections,
8617 and a <quote>+block{} +handle-as-image</quote>,
8618 which is the expanded form of one of our aliases that had been defined as:
8619 <quote>+block-as-image</quote>. (<link
8620 linkend="ALIASES"><quote>Aliases</quote></link> are defined in
8621 the first section of the actions file and typically used to combine more
8626 Any one of these would have done the trick and blocked this as an unwanted
8627 image. This is unnecessarily redundant since the last case effectively
8628 would also cover the first. No point in taking chances with these guys
8629 though ;-) Note that if you want an ad or obnoxious
8630 URL to be invisible, it should be defined as <quote>ad.doubleclick.net</quote>
8631 is done here -- as both a <link
8632 linkend="BLOCK"><quote>+block{}</quote></link>
8633 <emphasis>and</emphasis> an
8634 <link linkend="HANDLE-AS-IMAGE"><quote>+handle-as-image</quote></link>.
8635 The custom alias <quote><literal>+block-as-image</literal></quote> just
8636 simplifies the process and make it more readable.
8640 One last example. Let's try <quote>http://www.example.net/adsl/HOWTO/</quote>.
8641 This one is giving us problems. We are getting a blank page. Hmmm ...
8647 Matches for http://www.example.net/adsl/HOWTO/:
8649 In file: default.action <guibutton>[ View ]</guibutton> <guibutton>[ Edit ]</guibutton>
8653 -client-header-filter{hide-tor-exit-notation}
8654 -content-type-overwrite
8655 -crunch-client-header
8656 -crunch-if-none-match
8657 -crunch-incoming-cookies
8658 -crunch-outgoing-cookies
8659 -crunch-server-header
8661 -downgrade-http-version
8662 +fast-redirects {check-decoded-url}
8664 -filter {content-cookies}
8665 -filter {all-popups}
8666 -filter {banners-by-link}
8667 -filter {tiny-textforms}
8668 -filter {frameset-borders}
8669 -filter {demoronizer}
8670 -filter {shockwave-flash}
8671 -filter {quicktime-kioskmode}
8673 -filter {crude-parental}
8674 -filter {site-specifics}
8675 -filter {js-annoyances}
8676 -filter {html-annoyances}
8677 +filter {refresh-tags}
8678 -filter {unsolicited-popups}
8679 +filter {img-reorder}
8680 +filter {banners-by-size}
8682 +filter {jumping-windows}
8683 +filter {ie-exploits}
8690 -handle-as-empty-document
8692 -hide-accept-language
8693 -hide-content-disposition
8694 +hide-forwarded-for-headers
8695 +hide-from-header{block}
8696 +hide-referer{forge}
8700 -overwrite-last-modified
8701 +prevent-compression
8705 -server-header-filter{xml-to-html}
8706 -server-header-filter{html-to-xml}
8707 +session-cookies-only
8708 +set-image-blocker{blank} }
8711 { +block{Path contains "ads".} +handle-as-image }
8717 Ooops, the <quote>/adsl/</quote> is matching <quote>/ads</quote> in our
8718 configuration! But we did not want this at all! Now we see why we get the
8719 blank page. It is actually triggering two different actions here, and
8720 the effects are aggregated so that the URL is blocked, and &my-app; is told
8721 to treat the block as if it were an image. But this is, of course, all wrong.
8722 We could now add a new action below this (or better in our own
8723 <filename>user.action</filename> file) that explicitly
8724 <emphasis>un</emphasis> blocks (
8725 <link linkend="BLOCK"><quote>{-block}</quote></link>) paths with
8726 <quote>adsl</quote> in them (remember, last match in the configuration
8727 wins). There are various ways to handle such exceptions. Example:
8739 Now the page displays ;-)
8740 Remember to flush your browser's caches when making these kinds of changes to
8741 your configuration to insure that you get a freshly delivered page! Or, try
8742 using <literal>Shift+Reload</literal>.
8746 But now what about a situation where we get no explicit matches like
8753 { +block{Path starts with "ads".} +handle-as-image }
8759 That actually was very helpful and pointed us quickly to where the problem
8760 was. If you don't get this kind of match, then it means one of the default
8761 rules in the first section of <filename>default.action</filename> is causing
8762 the problem. This would require some guesswork, and maybe a little trial and
8763 error to isolate the offending rule. One likely cause would be one of the
8764 <link linkend="FILTER"><quote>+filter</quote></link> actions.
8765 These tend to be harder to troubleshoot.
8766 Try adding the URL for the site to one of aliases that turn off
8767 <link linkend="FILTER"><quote>+filter</quote></link>:
8775 .worldpay.com # for quietpc.com
8783 <quote><literal>{ shop }</literal></quote> is an <quote>alias</quote> that expands to
8784 <quote><literal>{ -filter -session-cookies-only }</literal></quote>.
8785 Or you could do your own exception to negate filtering:
8793 # Disable ALL filter actions for sites in this section
8801 This would turn off all filtering for these sites. This is best
8802 put in <filename>user.action</filename>, for local site
8803 exceptions. Note that when a simple domain pattern is used by itself (without
8804 the subsequent path portion), all sub-pages within that domain are included
8805 automatically in the scope of the action.
8809 Images that are inexplicably being blocked, may well be hitting the
8810 <link linkend="FILTER-BANNERS-BY-SIZE"><quote>+filter{banners-by-size}</quote></link>
8812 that images of certain sizes are ad banners (works well
8813 <emphasis>most of the time</emphasis> since these tend to be standardized).
8817 <quote><literal>{ fragile }</literal></quote> is an alias that disables most
8818 actions that are the most likely to cause trouble. This can be used as a
8819 last resort for problem sites.
8825 # Handle with care: easy to break
8827 mybank.example.com</screen>
8832 <emphasis>Remember to flush caches!</emphasis> Note that the
8833 <literal>mail.google</literal> reference lacks the TLD portion (e.g.
8834 <quote>.com</quote>). This will effectively match any TLD with
8835 <literal>google</literal> in it, such as <literal>mail.google.de.</literal>,
8839 If this still does not work, you will have to go through the remaining
8840 actions one by one to find which one(s) is causing the problem.
8849 This program is free software; you can redistribute it
8850 and/or modify it under the terms of the GNU General
8851 Public License as published by the Free Software
8852 Foundation; either version 2 of the License, or (at
8853 your option) any later version.
8855 This program is distributed in the hope that it will
8856 be useful, but WITHOUT ANY WARRANTY; without even the
8857 implied warranty of MERCHANTABILITY or FITNESS FOR A
8858 PARTICULAR PURPOSE. See the GNU General Public
8859 License for more details.
8861 The GNU General Public License should be included with
8862 this file. If not, you can view it at
8863 http://www.gnu.org/copyleft/gpl.html
8864 or write to the Free Software Foundation, Inc.,
8865 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
8868 $Log: user-manual.sgml,v $
8869 Revision 2.65 2008/03/04 18:30:40 fabiankeil
8870 Remove the treat-forbidden-connects-like-blocks action. We now
8871 use the "blocked" page for forbidden CONNECT requests by default.
8873 Revision 2.64 2008/03/01 14:10:28 fabiankeil
8874 Use new block syntax. Still needs some polishing.
8876 Revision 2.63 2008/02/22 05:50:37 markm68k
8879 Revision 2.62 2008/02/11 11:52:23 hal9
8880 Fix entity ... s/&/&
8882 Revision 2.61 2008/02/11 03:41:47 markm68k
8883 more updates for mac os x
8885 Revision 2.60 2008/02/11 03:40:25 markm68k
8886 more updates for mac os x
8888 Revision 2.59 2008/02/11 00:52:34 markm68k
8889 reflect new changes for mac os x
8891 Revision 2.58 2008/02/03 21:37:40 hal9
8892 Apply patch from Mark: s/OSX/OS X/
8894 Revision 2.57 2008/02/03 19:10:14 fabiankeil
8895 Mention forward-socks5.
8897 Revision 2.56 2008/01/31 19:11:35 fabiankeil
8898 Let the +client-header-filter{hide-tor-exit-notation} example apply
8899 to all requests as "tainted" Referers aren't limited to exit TLDs.
8901 Revision 2.55 2008/01/19 21:26:37 hal9
8902 Add IE7 to configuration section per Gerry.
8904 Revision 2.54 2008/01/19 17:52:39 hal9
8905 Re-commit to fix various minor issues for new release.
8907 Revision 2.53 2008/01/19 15:03:05 hal9
8908 Doc sources tagged for 3.0.8 release.
8910 Revision 2.52 2008/01/17 01:49:51 hal9
8911 Change copyright notice for docs s/2007/2008/. All these will be rebuilt soon
8914 Revision 2.51 2007/12/23 16:48:24 fabiankeil
8915 Use more precise example descriptions for the mysterious domain patterns.
8917 Revision 2.50 2007/12/08 12:44:36 fabiankeil
8918 - Remove already commented out pre-3.0.7 changes.
8919 - Update the "new log defaults" paragraph.
8921 Revision 2.49 2007/12/06 18:21:55 fabiankeil
8922 Update hide-forwarded-for-headers description.
8924 Revision 2.48 2007/11/24 19:07:17 fabiankeil
8925 - Mention request rewriting.
8926 - Enable the conditional-forge paragraph.
8929 Revision 2.47 2007/11/18 14:59:47 fabiankeil
8930 A few "Note to Upgraders" updates.
8932 Revision 2.46 2007/11/17 17:24:44 fabiankeil
8933 - Use new action defaults.
8934 - Minor fixes and rewordings.
8936 Revision 2.45 2007/11/16 11:48:46 hal9
8937 Fix one typo, and add a couple of small refinements.
8939 Revision 2.44 2007/11/15 03:30:20 hal9
8940 Results of spell check.
8942 Revision 2.43 2007/11/14 18:45:39 fabiankeil
8943 - Mention some more contributors in the "New in this Release" list.
8946 Revision 2.42 2007/11/12 03:32:40 hal9
8947 Updates for "What's New" and "Notes to Upgraders". Various other changes in
8948 preparation for new release. User Manual is almost ready.
8950 Revision 2.41 2007/11/11 16:32:11 hal9
8951 This is primarily syncing What's New and Note to Upgraders sections with the many
8952 new features and changes (gleaned from memory but mostly from ChangeLog).
8954 Revision 2.40 2007/11/10 17:10:59 fabiankeil
8955 In the first third of the file, mention several times that
8956 the action editor is disabled by default in 3.0.7 beta and later.
8958 Revision 2.39 2007/11/05 02:34:49 hal9
8959 Various changes in preparation for the upcoming release. Much yet to be done.
8961 Revision 2.38 2007/09/22 16:01:42 fabiankeil
8962 Update embedded show-url-info output.
8964 Revision 2.37 2007/08/27 16:09:55 fabiankeil
8965 Fix pre-chroot-nslookup description which I failed to
8966 copy and paste properly. Reported by Stephen Gildea.
8968 Revision 2.36 2007/08/26 16:47:14 fabiankeil
8969 Add Stephen Gildea's pre-chroot-nslookup patch [#1276666],
8970 extensive comments moved to user manual.
8972 Revision 2.35 2007/08/26 14:59:49 fabiankeil
8973 Minor rewordings and fixes.
8975 Revision 2.34 2007/08/05 15:19:50 fabiankeil
8976 - Don't claim HTTP/1.1 compliance.
8977 - Use $ in some of the path pattern examples.
8978 - Use a hide-user-agent example argument without
8979 leading and trailing space.
8980 - Make it clear that the cookie actions work with
8982 - Rephrase the inspect-jpegs text to underline
8983 that it's only meant to protect against a single
8986 Revision 2.33 2007/07/27 10:57:35 hal9
8987 Add references for user-agent strings for hide-user-agenet
8989 Revision 2.32 2007/06/07 12:36:22 fabiankeil
8990 Apply Roland's 29_usermanual.dpatch to fix a bunch
8991 of syntax errors I collected over the last months.
8993 Revision 2.31 2007/06/02 14:01:37 fabiankeil
8994 Start to document forward-override{}.
8996 Revision 2.30 2007/04/25 15:10:36 fabiankeil
8997 - Describe installation for FreeBSD.
8998 - Start to document taggers and tag patterns.
8999 - Don't confuse devils and daemons.
9001 Revision 2.29 2007/04/05 11:47:51 fabiankeil
9002 Some updates regarding header filtering,
9003 handling of compressed content and redirect's
9004 support for pcrs commands.
9006 Revision 2.28 2006/12/10 23:42:48 hal9
9007 Fix various typos reported by Adam P. Thanks.
9009 Revision 2.27 2006/11/14 01:57:47 hal9
9010 Dump all docs prior to 3.0.6 release. Various minor changes to faq and user
9013 Revision 2.26 2006/10/24 11:16:44 hal9
9016 Revision 2.25 2006/10/18 10:50:33 hal9
9017 Add note that since filters are off in Cautious, compression is ON. Turn off
9018 compression to make filters work on all sites.
9020 Revision 2.24 2006/10/03 11:13:54 hal9
9021 More references to the new filters. Include html this time around.
9023 Revision 2.23 2006/10/02 22:43:53 hal9
9024 Contains new filter definitions from Fabian, and few other miscellaneous
9027 Revision 2.22 2006/09/22 01:27:55 hal9
9028 Final commit of probably various minor changes here and there. Unless
9029 something changes this should be ready for pending release.
9031 Revision 2.21 2006/09/20 03:21:36 david__schmidt
9032 Just the tiniest tweak. Wafer thin!
9034 Revision 2.20 2006/09/10 14:53:54 hal9
9035 Results of spell check. User manual has some updates to standard.actions file
9038 Revision 2.19 2006/09/08 12:19:02 fabiankeil
9039 Adjust hide-if-modified-since example values
9040 to reflect the recent changes.
9042 Revision 2.18 2006/09/08 02:38:57 hal9
9044 -Fix a number of broken links.
9045 -Migrate the new Windows service command line options, and reference as
9047 -Rebuild so that can be used with the new "user-manual" config capabilities.
9050 Revision 2.17 2006/09/05 13:25:12 david__schmidt
9051 Add Windows service invocation stuff (duplicated) in FAQ and in user manual under Windows startup. One probably ought to reference the other.
9053 Revision 2.16 2006/09/02 12:49:37 hal9
9054 Various small updates for new actions, filterfiles, etc.
9056 Revision 2.15 2006/08/30 11:15:22 hal9
9057 More work on the new actions, especially filter-*-headers, and What's New
9058 section. User Manual is close to final form for 3.0.4 release. Some tinkering
9059 and proof reading left to do.
9061 Revision 2.14 2006/08/29 10:59:36 hal9
9062 Add a "Whats New in this release" Section. Further work on multiple filter
9063 files, and assorted other minor changes.
9065 Revision 2.13 2006/08/22 11:04:59 hal9
9066 Silence warnings and errors. This should build now. New filters were only
9067 stubbed in. More to be done.
9069 Revision 2.12 2006/08/14 08:40:39 fabiankeil
9070 Documented new actions that were part of
9071 the "minor Privoxy improvements".
9073 Revision 2.11 2006/07/18 14:48:51 david__schmidt
9074 Reorganizing the repository: swapping out what was HEAD (the old 3.1 branch)
9075 with what was really the latest development (the v_3_0_branch branch)
9077 Revision 1.123.2.43 2005/05/23 09:59:10 hal9
9080 Revision 1.123.2.42 2004/12/04 14:39:57 hal9
9081 Fix two minor typos per bug SF report.
9083 Revision 1.123.2.41 2004/03/23 12:58:42 oes
9086 Revision 1.123.2.40 2004/02/27 12:48:49 hal9
9087 Add comment re: redirecting to local file system for set-image-blocker may
9088 is dependent on browser.
9090 Revision 1.123.2.39 2004/01/30 22:31:40 oes
9091 Added a hint re bookmarklets to Quickstart section
9093 Revision 1.123.2.38 2004/01/30 16:47:51 oes
9094 Some minor clarifications
9096 Revision 1.123.2.37 2004/01/29 22:36:11 hal9
9097 Updates for no longer filtering text/plain, and demoronizer default settings,
9098 and copyright notice dates.
9100 Revision 1.123.2.36 2003/12/10 02:26:26 hal9
9101 Changed the demoronizer filter description.
9103 Revision 1.123.2.35 2003/11/06 13:36:37 oes
9104 Updated link to nightly CVS tarball
9106 Revision 1.123.2.34 2003/06/26 23:50:16 hal9
9107 Add a small bit on filtering and problems re: source code being corrupted.
9109 Revision 1.123.2.33 2003/05/08 18:17:33 roro
9110 Use apt-get instead of dpkg to install Debian package, which is more
9111 solid, uses the correct and most recent Debian version automatically.
9113 Revision 1.123.2.32 2003/04/11 03:13:57 hal9
9114 Add small note about only one filterfile (as opposed to multiple actions
9117 Revision 1.123.2.31 2003/03/26 02:03:43 oes
9118 Updated hard-coded copyright dates
9120 Revision 1.123.2.30 2003/03/24 12:58:56 hal9
9121 Add new section on Predefined Filters.
9123 Revision 1.123.2.29 2003/03/20 02:45:29 hal9
9124 More problems with \-\-chroot causing markup problems :(
9126 Revision 1.123.2.28 2003/03/19 00:35:24 hal9
9127 Manual edit of revision log because 'chroot' (even inside a comment) was
9128 causing Docbook to hang here (due to double hyphen and the processor thinking
9131 Revision 1.123.2.27 2003/03/18 19:37:14 oes
9132 s/Advanced|Radical/Adventuresome/g to avoid complaints re fun filter
9134 Revision 1.123.2.26 2003/03/17 16:50:53 oes
9135 Added documentation for new chroot option
9137 Revision 1.123.2.25 2003/03/15 18:36:55 oes
9138 Adapted to the new filters
9140 Revision 1.123.2.24 2002/11/17 06:41:06 hal9
9141 Move default profiles table from FAQ to U-M, and other minor related changes.
9144 Revision 1.123.2.23 2002/10/21 02:32:01 hal9
9145 Updates to the user.action examples section. A few new ones.
9147 Revision 1.123.2.22 2002/10/12 00:51:53 hal9
9148 Add demoronizer to filter section.
9150 Revision 1.123.2.21 2002/10/10 04:09:35 hal9
9151 s/Advanced/Radical/ and added very brief note.
9153 Revision 1.123.2.20 2002/10/10 03:49:21 hal9
9154 Add notes to session-cookies-only and Quickstart about pre-existing
9155 cookies. Also, note content-cookies work differently.
9157 Revision 1.123.2.19 2002/09/26 01:25:36 hal9
9158 More explanation on Privoxy patterns, more on content-cookies and SSL.
9160 Revision 1.123.2.18 2002/08/22 23:47:58 hal9
9161 Add 'Documentation' to Privoxy Menu shot in Configuration section to match
9164 Revision 1.123.2.17 2002/08/18 01:13:05 hal9
9165 Spell checked (only one typo this time!).
9167 Revision 1.123.2.16 2002/08/09 19:20:54 david__schmidt
9168 Update to Mac OS X startup script name
9170 Revision 1.123.2.15 2002/08/07 17:32:11 oes
9171 Converted some internal links from ulink to link for PDF creation; no content changed
9173 Revision 1.123.2.14 2002/08/06 09:16:13 oes
9174 Nits re: actions file download
9176 Revision 1.123.2.13 2002/08/02 18:23:19 g_sauthoff
9177 Just 2 small corrections to the Gentoo sections
9179 Revision 1.123.2.12 2002/08/02 18:17:21 g_sauthoff
9180 Added 2 Gentoo sections
9182 Revision 1.123.2.11 2002/07/26 15:20:31 oes
9183 - Added version info to title
9184 - Added info on new filters
9185 - Revised parts of the filter file tutorial
9186 - Added info on where to get updated actions files
9188 Revision 1.123.2.10 2002/07/25 21:42:29 hal9
9189 Add brief notes on not proxying non-HTTP protocols.
9191 Revision 1.123.2.9 2002/07/11 03:40:28 david__schmidt
9193 Updated Mac OS X sections due to installation location change
9195 Revision 1.123.2.8 2002/06/09 16:36:32 hal9
9196 Clarifications on filtering and MIME. Hardcode 'latest release' in index.html.
9198 Revision 1.123.2.7 2002/06/09 00:29:34 hal9
9199 Touch ups on filtering, in actions section and Anatomy.
9201 Revision 1.123.2.6 2002/06/06 23:11:03 hal9
9202 Fix broken link. Linkchecked all docs.
9204 Revision 1.123.2.5 2002/05/29 02:01:02 hal9
9205 This is break out of the entire config section from u-m, so it can
9206 eventually be used to generate the comments, etc in the main config file
9207 so that these are in sync with each other.
9209 Revision 1.123.2.4 2002/05/27 03:28:45 hal9
9210 Ooops missed something from David.
9212 Revision 1.123.2.3 2002/05/27 03:23:17 hal9
9213 Fix FIXMEs for OS2 and Mac OS X startup. Fix Redhat typos (should be Red Hat).
9214 That's a wrap, I think.
9216 Revision 1.123.2.2 2002/05/26 19:02:09 hal9
9217 Move Amiga stuff around to take of FIXME in start up section.
9219 Revision 1.123.2.1 2002/05/26 17:04:25 hal9
9220 -Spellcheck, very minor edits, and sync across branches
9222 Revision 1.123 2002/05/24 23:19:23 hal9
9223 Include new image (Proxy setup). More fun with guibutton.
9224 Minor corrections/clarifications here and there.
9226 Revision 1.122 2002/05/24 13:24:08 oes
9227 Added Bookmarklet for one-click pre-filled access to show-url-info
9229 Revision 1.121 2002/05/23 23:20:17 oes
9230 - Changed more (all?) references to actions to the
9231 <literal><link> style.
9232 - Small fixes in the actions chapter
9233 - Small clarifications in the quickstart to ad blocking
9234 - Removed <emphasis> from <title>s since the new doc CSS
9235 renders them red (bad in TOC).
9237 Revision 1.120 2002/05/23 19:16:43 roro
9238 Correct Debian specials (installation and startup).
9240 Revision 1.119 2002/05/22 17:17:05 oes
9243 Revision 1.118 2002/05/21 04:54:55 hal9
9244 -New Section: Quickstart to Ad Blocking
9245 -Reformat Actions Anatomy to match new CGI layout
9247 Revision 1.117 2002/05/17 13:56:16 oes
9248 - Reworked & extended Templates chapter
9249 - Small changes to Regex appendix
9250 - #included authors.sgml into (C) and hist chapter
9252 Revision 1.116 2002/05/17 03:23:46 hal9
9253 Fixing merge conflict in Quickstart section.
9255 Revision 1.115 2002/05/16 16:25:00 oes
9256 Extended the Filter File chapter & minor fixes
9258 Revision 1.114 2002/05/16 09:42:50 oes
9259 More ulink->link, added some hints to Quickstart section
9261 Revision 1.113 2002/05/15 21:07:25 oes
9262 Extended and further commented the example actions files
9264 Revision 1.112 2002/05/15 03:57:14 hal9
9265 Spell check. A few minor edits here and there for better syntax and
9268 Revision 1.111 2002/05/14 23:01:36 oes
9271 Revision 1.110 2002/05/14 19:10:45 oes
9272 Restored alphabetical order of actions
9274 Revision 1.109 2002/05/14 17:23:11 oes
9275 Renamed the prevent-*-cookies actions, extended aliases section and moved it before the example AFs
9277 Revision 1.108 2002/05/14 15:29:12 oes
9278 Completed proofreading the actions chapter
9280 Revision 1.107 2002/05/12 03:20:41 hal9
9281 Small clarifications for 127.0.0.1 vs localhost for listen-address since this
9282 apparently an important distinction for some OS's.
9284 Revision 1.106 2002/05/10 01:48:20 hal9
9285 This is mostly proposed copyright/licensing additions and changes. Docs
9286 are still GPL, but licensing and copyright are more visible. Also, copyright
9287 changed in doc header comments (eliminate references to JB except FAQ).
9289 Revision 1.105 2002/05/05 20:26:02 hal9
9290 Sorting out license vs copyright in these docs.
9292 Revision 1.104 2002/05/04 08:44:45 swa
9295 Revision 1.103 2002/05/04 00:40:53 hal9
9296 -Remove the TOC first page kludge. It's fixed proper now in ldp.dsl.in.
9297 -Some minor additions to Quickstart.
9299 Revision 1.102 2002/05/03 17:46:00 oes
9300 Further proofread & reactivated short build instructions
9302 Revision 1.101 2002/05/03 03:58:30 hal9
9303 Move the user-manual config directive to top of section. Add note about
9304 Privoxy needing read permissions for configs, and write for logs.
9306 Revision 1.100 2002/04/29 03:05:55 hal9
9307 Add clarification on differences of new actions files.
9309 Revision 1.99 2002/04/28 16:59:05 swa
9310 more structure in starting section
9312 Revision 1.98 2002/04/28 05:43:59 hal9
9313 This is the break up of configuration.html into multiple files. This
9314 will probably break links elsewhere :(
9316 Revision 1.97 2002/04/27 21:04:42 hal9
9317 -Rewrite of Actions File example.
9318 -Add section for user-manual directive in config.
9320 Revision 1.96 2002/04/27 05:32:00 hal9
9321 -Add short section to Filter Files to tie in with +filter action.
9322 -Start rewrite of examples in Actions Examples (not finished).
9324 Revision 1.95 2002/04/26 17:23:29 swa
9325 bookmarks cleaned, changed structure of user manual, screen and programlisting cleanups, and numerous other changes that I forgot
9327 Revision 1.94 2002/04/26 05:24:36 hal9
9328 -Add most of Andreas suggestions to Chain of Events section.
9329 -A few other minor corrections and touch up.
9331 Revision 1.92 2002/04/25 18:55:13 hal9
9332 More catchups on new actions files, and new actions names.
9333 Other assorted cleanups, and minor modifications.
9335 Revision 1.91 2002/04/24 02:39:31 hal9
9336 Add 'Chain of Events' section.
9338 Revision 1.90 2002/04/23 21:41:25 hal9
9339 Linuxconf is deprecated on RH, substitute chkconfig.
9341 Revision 1.89 2002/04/23 21:05:28 oes
9342 Added hint for startup on Red Hat
9344 Revision 1.88 2002/04/23 05:37:54 hal9
9345 Add AmigaOS install stuff.
9347 Revision 1.87 2002/04/23 02:53:15 david__schmidt
9348 Updated Mac OS X installation section
9349 Added a few English tweaks here an there
9351 Revision 1.86 2002/04/21 01:46:32 hal9
9352 Re-write actions section.
9354 Revision 1.85 2002/04/18 21:23:23 hal9
9355 Fix ugly typo (mine).
9357 Revision 1.84 2002/04/18 21:17:13 hal9
9358 Spell Redhat correctly (ie Red Hat). A few minor grammar corrections.
9360 Revision 1.83 2002/04/18 18:21:12 oes
9361 Added RPM install detail
9363 Revision 1.82 2002/04/18 12:04:50 oes
9366 Revision 1.81 2002/04/18 11:50:24 oes
9367 Extended Install section - needs fixing by packagers
9369 Revision 1.80 2002/04/18 10:45:19 oes
9370 Moved text to buildsource.sgml, renamed some filters, details
9372 Revision 1.79 2002/04/18 03:18:06 hal9
9373 Spellcheck, and minor touchups.
9375 Revision 1.78 2002/04/17 18:04:16 oes
9378 Revision 1.77 2002/04/17 13:51:23 oes
9379 Proofreading, part one
9381 Revision 1.76 2002/04/16 04:25:51 hal9
9382 -Added 'Note to Upgraders' and re-ordered the 'Quickstart' section.
9383 -Note about proxy may need requests to re-read config files.
9385 Revision 1.75 2002/04/12 02:08:48 david__schmidt
9386 Remove OS/2 building info... it is already in the developer-manual
9388 Revision 1.74 2002/04/11 00:54:38 hal9
9389 Add small section on submitting actions.
9391 Revision 1.73 2002/04/10 18:45:15 swa
9394 Revision 1.72 2002/04/10 04:06:19 hal9
9395 Added actions feedback to Bookmarklets section
9397 Revision 1.71 2002/04/08 22:59:26 hal9
9398 Version update. Spell chkconfig correctly :)
9400 Revision 1.70 2002/04/08 20:53:56 swa
9403 Revision 1.69 2002/04/06 05:07:29 hal9
9404 -Add privoxy-man-page.sgml, for man page.
9405 -Add authors.sgml for AUTHORS (and p-authors.sgml)
9406 -Reworked various aspects of various docs.
9407 -Added additional comments to sub-docs.
9409 Revision 1.68 2002/04/04 18:46:47 swa
9410 consistent look. reuse of copyright, history et. al.
9412 Revision 1.67 2002/04/04 17:27:57 swa
9413 more single file to be included at multiple points. make maintaining easier
9415 Revision 1.66 2002/04/04 06:48:37 hal9
9416 Structural changes to allow for conditional inclusion/exclusion of content
9417 based on entity toggles, e.g. 'entity % p-not-stable "INCLUDE"'. And
9418 definition of internal entities, e.g. 'entity p-version "2.9.13"' that will
9419 eventually be set by Makefile.
9420 More boilerplate text for use across multiple docs.
9422 Revision 1.65 2002/04/03 19:52:07 swa
9423 enhance squid section due to user suggestion
9425 Revision 1.64 2002/04/03 03:53:43 hal9
9426 A few minor bug fixes, and touch ups. Ready for review.
9428 Revision 1.63 2002/04/01 16:24:49 hal9
9429 Define entities to include boilerplate text. See doc/source/*.
9431 Revision 1.62 2002/03/30 04:15:53 hal9
9432 - Fix privoxy.org/config links.
9433 - Paste in Bookmarklets from Toggle page.
9434 - Move Quickstart nearer top, and minor rework.
9436 Revision 1.61 2002/03/29 01:31:08 hal9
9439 Revision 1.60 2002/03/27 01:57:34 hal9
9440 Added more to Anatomy section.
9442 Revision 1.59 2002/03/27 00:54:33 hal9
9443 Touch up intro for new name.
9445 Revision 1.58 2002/03/26 22:29:55 swa
9446 we have a new homepage!
9448 Revision 1.57 2002/03/24 20:33:30 hal9
9449 A few minor catch ups with name change.
9451 Revision 1.56 2002/03/24 16:17:06 swa
9452 configure needs to be generated.
9454 Revision 1.55 2002/03/24 16:08:08 swa
9455 we are too lazy to make a block-built
9456 privoxy logo. hence removed the option.
9458 Revision 1.54 2002/03/24 15:46:20 swa
9459 name change related issue.
9461 Revision 1.53 2002/03/24 11:51:00 swa
9462 name change. changed filenames.
9464 Revision 1.52 2002/03/24 11:01:06 swa
9467 Revision 1.51 2002/03/23 15:13:11 swa
9468 renamed every reference to the old name with foobar.
9469 fixed "application foobar application" tag, fixed
9470 "the foobar" with "foobar". left junkbustser in cvs
9471 comments and remarks to history untouched.
9473 Revision 1.50 2002/03/23 05:06:21 hal9
9476 Revision 1.49 2002/03/21 17:01:05 hal9
9477 New section in Appendix.
9479 Revision 1.48 2002/03/12 06:33:01 hal9
9480 Catching up to Andreas and re_filterfile changes.
9482 Revision 1.47 2002/03/11 13:13:27 swa
9483 correct feedback channels
9485 Revision 1.46 2002/03/10 00:51:08 hal9
9486 Added section on JB internal pages in Appendix.
9488 Revision 1.45 2002/03/09 17:43:53 swa
9491 Revision 1.44 2002/03/09 17:08:48 hal9
9492 New section on Jon's actions file editor, and move some stuff around.
9494 Revision 1.43 2002/03/08 00:47:32 hal9
9495 Added imageblock{pattern}.
9497 Revision 1.42 2002/03/07 18:16:55 swa
9500 Revision 1.41 2002/03/07 16:46:43 hal9
9501 Fix a few markup problems for jade.
9503 Revision 1.40 2002/03/07 16:28:39 swa
9504 provide correct feedback channels
9506 Revision 1.39 2002/03/06 16:19:28 hal9
9507 Note on perceived filtering slowdown per FR.
9509 Revision 1.38 2002/03/05 23:55:14 hal9
9510 Stupid I did it again. Double hyphen in comment breaks jade.
9512 Revision 1.37 2002/03/05 23:53:49 hal9
9513 jade barfs on '- -' embedded in comments. - -user option broke it.
9515 Revision 1.36 2002/03/05 22:53:28 hal9
9516 Add new - - user option.
9518 Revision 1.35 2002/03/05 00:17:27 hal9
9519 Added section on command line options.
9521 Revision 1.34 2002/03/04 19:32:07 oes
9522 Changed default port to 8118
9524 Revision 1.33 2002/03/03 19:46:13 hal9
9525 Emphasis on where/how to report bugs, etc
9527 Revision 1.32 2002/03/03 09:26:06 joergs
9528 AmigaOS changes, config is now loaded from PROGDIR: instead of
9529 AmiTCP:db/junkbuster/ if no configuration file is specified on the
9532 Revision 1.31 2002/03/02 22:45:52 david__schmidt
9535 Revision 1.30 2002/03/02 22:00:14 hal9
9536 Updated 'New Features' list. Ran through spell-checker.
9538 Revision 1.29 2002/03/02 20:34:07 david__schmidt
9539 Update OS/2 build section
9541 Revision 1.28 2002/02/24 14:34:24 jongfoster
9542 Formatting changes. Now changing the doctype to DocBook XML 4.1
9543 will work - no other changes are needed.
9545 Revision 1.27 2002/01/11 14:14:32 hal9
9546 Added a very short section on Templates
9548 Revision 1.26 2002/01/09 20:02:50 hal9
9549 Fix bug re: auto-detect config file changes.
9551 Revision 1.25 2002/01/09 18:20:30 hal9
9552 Touch ups for *.action files.
9554 Revision 1.24 2001/12/02 01:13:42 hal9
9557 Revision 1.23 2001/12/02 00:20:41 hal9
9558 Updates for recent changes.
9560 Revision 1.22 2001/11/05 23:57:51 hal9
9561 Minor update for startup now daemon mode.
9563 Revision 1.21 2001/10/31 21:11:03 hal9
9564 Correct 2 minor errors
9566 Revision 1.18 2001/10/24 18:45:26 hal9
9567 *** empty log message ***
9569 Revision 1.17 2001/10/24 17:10:55 hal9
9570 Catching up with Jon's recent work, and a few other things.
9572 Revision 1.16 2001/10/21 17:19:21 swa
9573 wrong url in documentation
9575 Revision 1.15 2001/10/14 23:46:24 hal9
9576 Various minor changes. Fleshed out SEE ALSO section.
9578 Revision 1.13 2001/10/10 17:28:33 hal9
9581 Revision 1.12 2001/09/28 02:57:04 hal9
9584 Revision 1.11 2001/09/28 02:25:20 hal9
9587 Revision 1.9 2001/09/27 23:50:29 hal9
9588 A few changes. A short section on regular expression in appendix.
9590 Revision 1.8 2001/09/25 00:34:59 hal9
9591 Some additions, and re-arranging.
9593 Revision 1.7 2001/09/24 14:31:36 hal9
9596 Revision 1.6 2001/09/24 14:10:32 hal9
9597 Including David's OS/2 installation instructions.
9599 Revision 1.2 2001/09/13 15:27:40 swa
9602 Revision 1.1 2001/09/12 15:36:41 swa
9603 source files for junkbuster documentation
9605 Revision 1.3 2001/09/10 17:43:59 swa
9606 first proposal of a structure.
9608 Revision 1.2 2001/06/13 14:28:31 swa
9609 docs should have an author.
9611 Revision 1.1 2001/06/13 14:20:37 swa
9612 first import of project's documentation for the webserver.