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 2.60 2008/02/11 03:40:25 markm68k 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 2.60 2008/02/11 03:40:25 markm68k 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, download and install the
317 <ulink url="https://sourceforge.net/project/showfiles.php?group_id=11118&package_id=29783">Privoxy Utility</ulink> for Mac OS X.
318 This application controls the privoxy service (e.g. starting and
319 stopping the service as well as uninstalling the software).
323 <!-- ~~~~~ New section ~~~~~ -->
324 <sect3 id="installation-amiga"><title>AmigaOS</title>
326 Copy and then unpack the <filename>lha</filename> archive to a suitable location.
327 All necessary files will be installed into <application>Privoxy</application>
328 directory, including all configuration and log files. To uninstall, just
329 remove this directory.
333 <!-- ~~~~~ New section ~~~~~ -->
334 <sect3 id="installation-tbz"><title>FreeBSD</title>
337 Privoxy is part of FreeBSD's Ports Collection, you can build and install
338 it with <literal>cd /usr/ports/www/privoxy; make install clean</literal>.
341 If you don't use the ports, you can fetch and install
342 the package with <literal>pkg_add -r privoxy</literal>.
345 The port skeleton and the package can also be downloaded from the
346 <ulink url="https://sourceforge.net/project/showfiles.php?group_id=11118">File Release
347 Page</ulink>, but there's no reason to use them unless you're interested in the
348 beta releases which are only available there.
352 <!-- ~~~~~ New section ~~~~~ -->
353 <sect3 id="installattion-gentoo"><title>Gentoo</title>
355 Gentoo source packages (Ebuilds) for <application>Privoxy</application> are
356 contained in the Gentoo Portage Tree (they are not on the download page,
357 but there is a Gentoo section, where you can see when a new
358 <application>Privoxy</application> Version is added to the Portage Tree).
361 Before installing <application>Privoxy</application> under Gentoo just do
362 first <literal>emerge rsync</literal> to get the latest changes from the
363 Portage tree. With <literal>emerge privoxy</literal> you install the latest
367 Configuration files are in <filename>/etc/privoxy</filename>, the
368 documentation is in <filename>/usr/share/doc/privoxy-&p-version;</filename>
369 and the Log directory is in <filename>/var/log/privoxy</filename>.
375 <!-- ~~~~~ New section ~~~~~ -->
376 <sect2 id="installation-source"><title>Building from Source</title>
379 The most convenient way to obtain the <application>Privoxy</application> sources
380 is to download the source tarball from our
381 <ulink url="http://sourceforge.net/project/showfiles.php?group_id=11118&package_id=10571">project download
386 If you like to live on the bleeding edge and are not afraid of using
387 possibly unstable development versions, you can check out the up-to-the-minute
388 version directly from <ulink url="http://sourceforge.net/cvs/?group_id=11118">the
389 CVS repository</ulink>.
391 deprecated...out of business.
392 or simply download <ulink
393 url="http://cvs.sourceforge.net/cvstarballs/ijbswa-cvsroot.tar.bz2">the nightly CVS
398 <!-- include buildsource.sgml boilerplate: -->
400 <!-- end boilerplate -->
403 <!-- ~~~~~ New section ~~~~~ -->
404 <sect2 id="installation-keepupdated"><title>Keeping your Installation Up-to-Date</title>
406 As user feedback comes in and development continues, we will make updated versions
407 of both the main <link linkend="actions-file">actions file</link> (as a <ulink
408 url="http://sourceforge.net/project/showfiles.php?group_id=11118&release_id=103670">separate
409 package</ulink>) and the software itself (including the actions file) available for
414 If you wish to receive an email notification whenever we release updates of
415 <application>Privoxy</application> or the actions file, <ulink
416 url="http://lists.sourceforge.net/lists/listinfo/ijbswa-announce/">subscribe
417 to our announce mailing list</ulink>, ijbswa-announce@lists.sourceforge.net.
421 In order not to lose your personal changes and adjustments when updating
422 to the latest <literal>default.action</literal> file we <emphasis>strongly
423 recommend</emphasis> that you use <literal>user.action</literal> and
424 <literal>user.filter</literal> for your local
425 customizations of <application>Privoxy</application>. See the <link
426 linkend="actions-file">Chapter on actions files</link> for details.
434 <!-- ~ End section ~ -->
436 <!-- ~~~~~ New section ~~~~~ -->
437 <sect1 id="whatsnew">
438 <title>What's New in this Release</title>
440 There are many improvements and new features since <application>Privoxy 3.0.6</application>, the last stable release:
447 Two new actions <link
448 linkend="server-header-tagger">server-header-tagger</link>
450 linkend="client-header-tagger">client-header-tagger</link>
451 that can be used to create arbitrary <quote>tags</quote>
452 based on client and server headers.
453 These <quote>tags</quote> can then subsequently be used
454 to control the other actions used for the current request,
455 greatly increasing &my-app;'s flexibility and selectivity. See <link
456 linkend="tag-pattern">tag patterns</link> for more information on tags.
462 Header filtering is done with dedicated header filters now. As a result
463 the actions <quote>filter-client-headers</quote> and <quote>filter-server-headers</quote>
464 that were introduced with <application>Privoxy 3.0.5</application> to apply
465 content filters to the headers have been removed.
466 See the new actions <link
467 linkend="server-header-filter">server-header-filter</link>
469 linkend="client-header-filter">client-header-filter</link> for details.
474 There are four new options for the main <filename>config</filename> file:
481 linkend="allow-cgi-request-crunching">allow-cgi-request-crunching</link>
482 which allows requests for Privoxy's internal CGI pages to be
483 blocked, redirected or (un)trusted like ordinary requests.
489 linkend="split-large-forms">split-large-forms</link>
490 that will work around a browser bug that caused IE6 and IE7 to
491 ignore the Submit button on the Privoxy's edit-actions-for-url CGI
498 linkend="accept-intercepted-requests">accept-intercepted-requests</link>
499 which allows to combine Privoxy with any packet filter to create an
500 intercepting proxy for HTTP/1.1 requests (and for HTTP/1.0 requests
501 with Host header set). This means clients can be forced to use
502 &my-app; even if their proxy settings are configured differently.
508 linkend="templdir">templdir</link>
509 to designate an alternate location for &my-app;'s
510 locally customized CGI templates so that
511 these are not overwritten during upgrades.
519 A new command line option <literal>--pre-chroot-nslookup hostname</literal> to
520 initialize the resolver library before chroot'ing. On some systems this
521 reduces the number of files that must be copied into the chroot tree.
522 (Patch provided by Stephen Gildea)
529 linkend="forward-override">forward-override</link> action
530 allows changing of the forwarding settings through the actions files.
531 Combined with tags, this allows to choose the forwarder based on
532 client headers like the <literal>User-Agent</literal>, or the request origin.
539 linkend="redirect">redirect</link> action can now use regular
540 expression substitutions against the original URL.
546 <application>zlib</application> support is now available as a compile
547 time option to filter compressed content. Patch provided by Wil Mahan.
552 Improve various filters, and add new ones.
559 Include support for RFC 3253 so that <filename>Subversion</filename> works
560 with &my-app;. Patch provided by Petr Kadlec.
566 Logging can be completely turned off by not specifying a logfile directive.
573 A number of improvements to Privoxy's internal CGI pages, including the
574 use of favicons for error and control pages.
580 Many bugfixes, memory leaks addressed, code improvements, and logging
588 For a more detailed list of changes please have a look at the ChangeLog.
591 <!-- ~~~~~ New section ~~~~~ -->
593 <sect2 id="upgradersnote">
594 <title>Note to Upgraders</title>
597 A quick list of things to be aware of before upgrading from earlier
598 versions of <application>Privoxy</application>:
606 The recommended way to upgrade &my-app; is to backup your old
607 configuration files, install the new ones, verify that &my-app;
608 is working correctly and finally merge back your changes using
609 <application>diff</application> and maybe <application>patch</application>.
612 There are a number of new features in each &my-app; release and
613 most of them have to be explicitly enabled in the configuration
614 files. Old configuration files obviously don't do that and due
615 to syntax changes using old configuration files with a new
616 &my-app; isn't always possible anyway.
621 Note that some installers remove earlier versions completely,
622 including configuration files, therefore you should really save
623 any important configuration files!
628 On the other hand, other installers don't overwrite existing configuration
629 files, thinking you will want to do that yourself.
634 <filename>standard.action</filename> now only includes the enabled actions.
635 Not all actions as before.
640 In the default configuration only fatal errors are logged now.
641 You can change that in the <link linkend="DEBUG">debug section</link>
642 of the configuration file. You may also want to enable more verbose
643 logging until you verified that the new &my-app; version is working
650 Three other config file settings are now off by default:
651 <link linkend="enable-remote-toggle">enable-remote-toggle</link>,
652 <link linkend="enable-remote-http-toggle">enable-remote-http-toggle</link>,
653 and <link linkend="enable-edit-actions">enable-edit-actions</link>.
654 If you use or want these, you will need to explicitly enable them, and
655 be aware of the security issues involved.
661 The <quote>filter-client-headers</quote> and
662 <quote>filter-server-headers</quote> actions that were introduced with
663 <application>Privoxy 3.0.5</application> to apply content filters to
664 the headers have been removed and replaced with new actions.
666 linkend="whatsnew">What's New section</link> above.
674 What constitutes a <quote>default</quote> configuration has changed,
675 and you may want to review which actions are <quote>on</quote> by
676 default. This is primarily a matter of emphasis, but some features
677 you may have been used to, may now be <quote>off</quote> by default.
678 There are also a number of new actions and filters you may want to
679 consider, most of which are not fully incorporated into the default
680 settings as yet (see above).
687 The default actions setting is now <literal>Cautious</literal>. Previous
688 releases had a default setting of <literal>Medium</literal>. Experienced
689 users may want to adjust this, as it is fairly conservative by &my-app;
690 standards and past practices. See <ulink
691 url="http://config.privoxy.org/edit-actions-list?f=default">
692 http://config.privoxy.org/edit-actions-list?f=default</ulink>. New users
693 should try the default settings for a while before turning up the volume.
699 The default setting has filtering turned <emphasis>off</emphasis>, which
700 subsequently means that compression is <emphasis>on</emphasis>. Remember
701 that filtering does not work on compressed pages, so if you use, or want to
702 use, filtering, you will need to force compression off. Example:
706 { +<link linkend="filter">filter</link>{google} +<link linkend="prevent-compression">prevent-compression</link> }
710 Or if you use a number of filters, or filter many sites, you may just want
711 to turn off compression for all sites in
712 <filename>default.action</filename> (or
713 <filename>user.action</filename>).
720 Also, <link linkend="SESSION-COOKIES-ONLY">session-cookies-only</link> is
721 off by default now. If you've liked this feature in the past, you may want
722 to turn it back on in <filename>user.action</filename> now.
729 Some installers may not automatically start
730 <application>Privoxy</application> after installation.
741 <!-- ~~~~~ New section ~~~~~ -->
742 <sect1 id="quickstart"><title>Quickstart to Using Privoxy</title>
748 Install <application>Privoxy</application>. See the <link
749 linkend="installation">Installation Section</link> below for platform specific
756 Advanced users and those who want to offer <application>Privoxy</application>
757 service to more than just their local machine should check the <link
758 linkend="config">main config file</link>, especially the <link
759 linkend="access-control">security-relevant</link> options. These are
766 Start <application>Privoxy</application>, if the installation program has
767 not done this already (may vary according to platform). See the section
768 <link linkend="startup">Starting <application>Privoxy</application></link>.
774 Set your browser to use <application>Privoxy</application> as HTTP and
775 HTTPS (SSL) <ulink url="http://en.wikipedia.org/wiki/Proxy_server">proxy</ulink>
776 by setting the proxy configuration for address of
777 <literal>127.0.0.1</literal> and port <literal>8118</literal>.
778 <emphasis>DO NOT</emphasis> activate proxying for <literal>FTP</literal> or
779 any protocols besides HTTP and HTTPS (SSL) unless you intend to prevent your
780 browser from using these protocols.
786 Flush your browser's disk and memory caches, to remove any cached ad images.
787 If using <application>Privoxy</application> to manage
788 <ulink url="http://en.wikipedia.org/wiki/Browser_cookie">cookies</ulink>,
789 you should remove any currently stored cookies too.
795 A default installation should provide a reasonable starting point for
796 most. There will undoubtedly be occasions where you will want to adjust the
797 configuration, but that can be dealt with as the need arises. Little
798 to no initial configuration is required in most cases, you may want
800 <ulink url="config.html#ENABLE-EDIT-ACTIONS">web-based action editor</ulink> though.
801 Be sure to read the warnings first.
804 See the <link linkend="configuration">Configuration section</link> for more
805 configuration options, and how to customize your installation.
806 You might also want to look at the <link
807 linkend="quickstart-ad-blocking">next section</link> for a quick
808 introduction to how <application>Privoxy</application> blocks ads and
815 If you experience ads that slip through, innocent images that are
816 blocked, or otherwise feel the need to fine-tune
817 <application>Privoxy's</application> behavior, take a look at the <link
818 linkend="actions-file">actions files</link>. As a quick start, you might
819 find the <link linkend="act-examples">richly commented examples</link>
820 helpful. You can also view and edit the actions files through the <ulink
821 url="http://config.privoxy.org">web-based user interface</ulink>. The
822 Appendix <quote><link linkend="actionsanat">Troubleshooting: Anatomy of an
823 Action</link></quote> has hints on how to understand and debug actions that
824 <quote>misbehave</quote>.
829 Did anyone test these lately?
833 For easy access to &my-app;'s most important controls, drag the provided
834 <link linkend="bookmarklets">Bookmarklets</link> into your browser's
842 Please see the section <link linkend="contact">Contacting the
843 Developers</link> on how to report bugs, problems with websites or to get
850 Now enjoy surfing with enhanced control, comfort and privacy!
858 <!-- ~~~~~ New section ~~~~~ -->
860 <sect2 id="quickstart-ad-blocking">
861 <title>Quickstart to Ad Blocking</title>
863 NOTE: This section is deliberately redundant for those that don't
864 want to read the whole thing (which is getting lengthy).
867 Ad blocking is but one of <application>Privoxy's</application>
868 array of features. Many of these features are for the technically minded advanced
869 user. But, ad and banner blocking is surely common ground for everybody.
872 This section will provide a quick summary of ad blocking so
873 you can get up to speed quickly without having to read the more extensive
874 information provided below, though this is highly recommended.
877 First a bit of a warning ... blocking ads is much like blocking SPAM: the
878 more aggressive you are about it, the more likely you are to block
879 things that were not intended. And the more likely that some things
880 may not work as intended. So there is a trade off here. If you want
881 extreme ad free browsing, be prepared to deal with more
882 <quote>problem</quote> sites, and to spend more time adjusting the
883 configuration to solve these unintended consequences. In short, there is
884 not an easy way to eliminate <emphasis>all</emphasis> ads. Either take
885 the easy way and settle for <emphasis>most</emphasis> ads blocked with the
886 default configuration, or jump in and tweak it for your personal surfing
887 habits and preferences.
890 Secondly, a brief explanation of <application>Privoxy's </application>
891 <quote>actions</quote>. <quote>Actions</quote> in this context, are
892 the directives we use to tell <application>Privoxy</application> to perform
893 some task relating to HTTP transactions (i.e. web browsing). We tell
894 <application>Privoxy</application> to take some <quote>action</quote>. Each
895 action has a unique name and function. While there are many potential
896 <application>actions</application> in <application>Privoxy's</application>
897 arsenal, only a few are used for ad blocking. <link
898 linkend="actions">Actions</link>, and <link linkend="actions-file">action
899 configuration files</link>, are explained in depth below.
902 Actions are specified in <application>Privoxy's</application> configuration,
903 followed by one or more URLs to which the action should apply. URLs
904 can actually be URL type <link linkend="af-patterns">patterns</link> that use
905 wildcards so they can apply potentially to a range of similar URLs. The
906 actions, together with the URL patterns are called a section.
909 When you connect to a website, the full URL will either match one or more
910 of the sections as defined in <application>Privoxy's</application> configuration,
911 or not. If so, then <application>Privoxy</application> will perform the
912 respective actions. If not, then nothing special happens. Furthermore, web
913 pages may contain embedded, secondary URLs that your web browser will
914 use to load additional components of the page, as it parses the
915 original page's HTML content. An ad image for instance, is just an URL
916 embedded in the page somewhere. The image itself may be on the same server,
917 or a server somewhere else on the Internet. Complex web pages will have many
918 such embedded URLs. &my-app; can deal with each URL individually, so, for
919 instance, the main page text is not touched, but images from such-and-such
924 The most important actions for basic ad blocking are: <literal><link
925 linkend="block">block</link></literal>, <literal><link
926 linkend="handle-as-image">handle-as-image</link></literal>,
928 linkend="handle-as-empty-document">handle-as-empty-document</link></literal>,and
929 <literal><link linkend="set-image-blocker">set-image-blocker</link></literal>:
937 <literal><link linkend="block">block</link></literal> - this is perhaps
938 the single most used action, and is particularly important for ad blocking.
939 This action stops any contact between your browser and any URL patterns
940 that match this action's configuration. It can be used for blocking ads,
941 but also anything that is determined to be unwanted. By itself, it simply
942 stops any communication with the remote server and sends
943 <application>Privoxy</application>'s own built-in BLOCKED page instead to
944 let you now what has happened (with some exceptions, see below).
950 <literal><link linkend="handle-as-image">handle-as-image</link></literal> -
951 tells <application>Privoxy</application> to treat this URL as an image.
952 <application>Privoxy</application>'s default configuration already does this
953 for all common image types (e.g. GIF), but there are many situations where this
954 is not so easy to determine. So we'll force it in these cases. This is particularly
955 important for ad blocking, since only if we know that it's an image of
956 some kind, can we replace it with an image of our choosing, instead of the
957 <application>Privoxy</application> BLOCKED page (which would only result in
958 a <quote>broken image</quote> icon). There are some limitations to this
959 though. For instance, you can't just brute-force an image substitution for
960 an entire HTML page in most situations.
966 <literal><link linkend="handle-as-empty-document">handle-as-empty-document</link></literal> -
967 sends an empty document instead of <application>Privoxy's</application>
968 normal BLOCKED HTML page. This is useful for file types that are neither
969 HTML nor images, such as blocking JavaScript files.
976 linkend="set-image-blocker">set-image-blocker</link></literal> - tells
977 <application>Privoxy</application> what to display in place of an ad image that
978 has hit a block rule. For this to come into play, the URL must match a
979 <literal><link linkend="block">block</link></literal> action somewhere in the
980 configuration, <emphasis>and</emphasis>, it must also match an
981 <literal><link linkend="handle-as-image">handle-as-image</link></literal> action.
984 The configuration options on what to display instead of the ad are:
988 <emphasis>pattern</emphasis> - a checkerboard pattern, so that an ad
989 replacement is obvious. This is the default.
994 <emphasis>blank</emphasis> - A very small empty GIF image is displayed.
995 This is the so-called <quote>invisible</quote> configuration option.
1000 <emphasis>http://<URL></emphasis> - A redirect to any image anywhere
1001 of the user's choosing (advanced usage).
1010 Advanced users will eventually want to explore &my-app;
1011 <literal><link linkend="filter">filters</link></literal> as well. Filters
1012 are very different from <literal><link
1013 linkend="block">blocks</link></literal>.
1014 A <quote>block</quote> blocks a site, page, or unwanted contented. Filters
1015 are a way of filtering or modifying what is actually on the page. An example
1016 filter usage: a text replacement of <quote>no-no</quote> for
1017 <quote>nasty-word</quote>. That is a very simple example. This process can be
1018 used for ad blocking, but it is more in the realm of advanced usage and has
1019 some pitfalls to be wary off.
1023 The quickest way to adjust any of these settings is with your browser through
1024 the special <application>Privoxy</application> editor at <ulink
1025 url="http://config.privoxy.org/show-status">http://config.privoxy.org/show-status</ulink>
1026 (shortcut: <ulink url="http://p.p/">http://p.p/show-status</ulink>). This
1027 is an internal page, and does not require Internet access.
1031 Note that as of <application>Privoxy</application> 3.0.7 beta the
1032 action editor is disabled by default. Check the
1033 <ulink url="config.html#ENABLE-EDIT-ACTIONS">enable-edit-actions
1034 section in the configuration file</ulink> to learn why and in which
1035 cases it's safe to enable again.
1039 If you decided to enable the action editor, select the appropriate
1040 <quote>actions</quote> file, and click
1041 <quote><guibutton>Edit</guibutton></quote>. It is best to put personal or
1042 local preferences in <filename>user.action</filename> since this is not
1043 meant to be overwritten during upgrades, and will over-ride the settings in
1044 other files. Here you can insert new <quote>actions</quote>, and URLs for ad
1045 blocking or other purposes, and make other adjustments to the configuration.
1046 <application>Privoxy</application> will detect these changes automatically.
1050 A quick and simple step by step example:
1058 Right click on the ad image to be blocked, then select
1059 <quote><guimenuitem>Copy Link Location</guimenuitem></quote> from the
1067 url="http://config.privoxy.org/show-status">http://config.privoxy.org/show-status</ulink>
1072 Find <filename>user.action</filename> in the top section, and click
1073 on <quote><guibutton>Edit</guibutton></quote>:
1076 <!-- image of editor and actions files selections -->
1078 <figure pgwide="0" float="0"><title>Actions Files in Use</title>
1081 <imagedata fileref="files-in-use.jpg" format="jpg">
1084 <phrase>[ Screenshot of Actions Files in Use ]</phrase>
1093 You should have a section with only
1094 <literal><link linkend="block">block</link></literal> listed under
1095 <quote>Actions:</quote>.
1096 If not, click a <quote><guibutton>Insert new section below</guibutton></quote>
1097 button, and in the new section that just appeared, click the
1098 <guibutton>Edit</guibutton> button right under the word <quote>Actions:</quote>.
1099 This will bring up a list of all actions. Find
1100 <literal><link linkend="block">block</link></literal> near the top, and click
1101 in the <quote>Enabled</quote> column, then <quote><guibutton>Submit</guibutton></quote>
1102 just below the list.
1107 Now, in the <literal><link linkend="block">block</link></literal> actions section,
1108 click the <quote><guibutton>Add</guibutton></quote> button, and paste the URL the
1109 browser got from <quote><guimenuitem>Copy Link Location</guimenuitem></quote>.
1110 Remove the <literal>http://</literal> at the beginning of the URL. Then, click
1111 <quote><guibutton>Submit</guibutton></quote> (or
1112 <quote><guibutton>OK</guibutton></quote> if in a pop-up window).
1117 Now go back to the original page, and press <keycap>SHIFT-Reload</keycap>
1118 (or flush all browser caches). The image should be gone now.
1126 This is a very crude and simple example. There might be good reasons to use a
1127 wildcard pattern match to include potentially similar images from the same
1128 site. For a more extensive explanation of <quote>patterns</quote>, and
1129 the entire actions concept, see <link linkend="actions-file">the Actions
1134 For advanced users who want to hand edit their config files, you might want
1135 to now go to the <link linkend="act-examples">Actions Files Tutorial</link>.
1136 The ideas explained therein also apply to the web-based editor.
1139 There are also various
1140 <link linkend="filter">filters</link> that can be used for ad blocking
1141 (filters are a special subset of actions). These
1142 fall into the <quote>advanced</quote> usage category, and are explained in
1143 depth in later sections.
1150 <!-- ~ End section ~ -->
1153 <!-- ~~~~~ New section ~~~~~ -->
1154 <sect1 id="startup">
1155 <title>Starting Privoxy</title>
1157 Before launching <application>Privoxy</application> for the first time, you
1158 will want to configure your browser(s) to use
1159 <application>Privoxy</application> as a HTTP and HTTPS (SSL)
1160 <ulink url="http://en.wikipedia.org/wiki/Proxy_server">proxy</ulink>. The default is
1161 127.0.0.1 (or localhost) for the proxy address, and port 8118 (earlier versions
1162 used port 8000). This is the one configuration step <emphasis>that must be done
1166 Please note that <application>Privoxy</application> can only proxy HTTP and
1167 HTTPS traffic. It will not work with FTP or other protocols.
1170 <!-- image of Mozilla Proxy configuration -->
1172 <figure pgwide="0" float="0"><title>Proxy Configuration Showing
1173 Mozilla/Netscape HTTP and HTTPS (SSL) Settings</title>
1176 <imagedata fileref="proxy_setup.jpg" format="jpg">
1179 <phrase>[ Screenshot of Mozilla Proxy Configuration ]</phrase>
1187 With <application>Firefox</application>, this is typically set under:
1191 <guibutton>Tools</guibutton> -> <guibutton>Options</guibutton> -> <guibutton>Advanced</guibutton> -> <guibutton>Network</guibutton> -><guibutton>Connection</guibutton> -> <guibutton>Settings</guibutton>
1196 Or optionally on some platforms:
1200 <guibutton>Edit</guibutton> -> <guibutton>Preferences</guibutton> -> <guibutton>General</guibutton> -> <guibutton>Connection Settings</guibutton> -> <guibutton>Manual Proxy Configuration</guibutton>
1206 With <application>Netscape</application> (and
1207 <application>Mozilla</application>), this can be set under:
1212 <!-- Mix ascii and gui art, something for everybody -->
1213 <!-- spacing on this is tricky -->
1214 <guibutton>Edit</guibutton> -> <guibutton>Preferences</guibutton> -> <guibutton>Advanced</guibutton> -> <guibutton>Proxies</guibutton> -> <guibutton>HTTP Proxy</guibutton>
1219 For <application>Internet Explorer v.5-7</application>:
1223 <guibutton>Tools</guibutton> -> <guibutton>Internet Options</guibutton> -> <guibutton>Connections</guibutton> -> <guibutton>LAN Settings</guibutton>
1227 Then, check <quote>Use Proxy</quote> and fill in the appropriate info
1228 (Address: 127.0.0.1, Port: 8118). Include HTTPS (SSL), if you want HTTPS
1229 proxy support too (sometimes labeled <quote>Secure</quote>). Make sure any
1230 checkboxes like <quote>Use the same proxy server for all protocols</quote> is
1231 <emphasis>UNCHECKED</emphasis>. You want only HTTP and HTTPS (SSL)!
1234 <!-- image of IE Proxy configuration -->
1236 <figure pgwide="0" float="0"><title>Proxy Configuration Showing
1237 Internet Explorer HTTP and HTTPS (Secure) Settings</title>
1240 <imagedata fileref="proxy2.jpg" format="jpg">
1243 <phrase>[ Screenshot of IE Proxy Configuration ]</phrase>
1251 After doing this, flush your browser's disk and memory caches to force a
1252 re-reading of all pages and to get rid of any ads that may be cached. Remove
1253 any <ulink url="http://en.wikipedia.org/wiki/Browser_cookie">cookies</ulink>,
1254 if you want <application>Privoxy</application> to manage that. You are now
1255 ready to start enjoying the benefits of using
1256 <application>Privoxy</application>!
1260 <application>Privoxy</application> itself is typically started by specifying the
1261 main configuration file to be used on the command line. If no configuration
1262 file is specified on the command line, <application>Privoxy</application>
1263 will look for a file named <filename>config</filename> in the current
1264 directory. Except on Win32 where it will try <filename>config.txt</filename>.
1267 <sect2 id="start-redhat">
1268 <title>Red Hat and Fedora</title>
1270 A default Red Hat installation may not start &my-app; upon boot. It will use
1271 the file <filename>/etc/privoxy/config</filename> as its main configuration
1276 # /etc/rc.d/init.d/privoxy start
1284 # service privoxy start
1289 <sect2 id="start-debian">
1290 <title>Debian</title>
1292 We use a script. Note that Debian typically starts &my-app; upon booting per
1293 default. It will use the file
1294 <filename>/etc/privoxy/config</filename> as its main configuration
1299 # /etc/init.d/privoxy start
1304 <sect2 id="start-windows">
1305 <title>Windows</title>
1307 Click on the &my-app; Icon to start <application>Privoxy</application>. If no configuration file is
1308 specified on the command line, <application>Privoxy</application> will look
1309 for a file named <filename>config.txt</filename>. Note that Windows will
1310 automatically start &my-app; when the system starts if you chose that option
1314 <application>Privoxy</application> can run with full Windows service functionality.
1315 On Windows only, the &my-app; program has two new command line arguments
1316 to install and uninstall &my-app; as a service. See the
1317 <link linkend="installation-pack-win">Windows Installation
1318 instructions</link> for details.
1322 <sect2 id="start-unices">
1323 <title>Solaris, NetBSD, FreeBSD, HP-UX and others</title>
1325 Example Unix startup command:
1329 # /usr/sbin/privoxy /etc/privoxy/config
1334 <sect2 id="start-os2">
1337 During installation, <application>Privoxy</application> is configured to
1338 start automatically when the system restarts. You can start it manually by
1339 double-clicking on the <application>Privoxy</application> icon in the
1340 <application>Privoxy</application> folder.
1344 <sect2 id="start-macosx">
1345 <title>Mac OS X</title>
1347 During installation, <application>Privoxy</application> is configured to
1348 start automatically when the system restarts. To start &my-app; manually,
1349 double-click on the <literal>StartPrivoxy.command</literal> icon in the
1350 <literal>/Library/Privoxy</literal> folder. Or, type this command
1355 /Library/Privoxy/StartPrivoxy.command
1359 You will be prompted for the administrator password.
1364 <sect2 id="start-amigaos">
1365 <title>AmigaOS</title>
1367 Start <application>Privoxy</application> (with RUN <>NIL:) in your
1368 <filename>startnet</filename> script (AmiTCP), in
1369 <filename>s:user-startup</filename> (RoadShow), as startup program in your
1370 startup script (Genesis), or as startup action (Miami and MiamiDx).
1371 <application>Privoxy</application> will automatically quit when you quit your
1372 TCP/IP stack (just ignore the harmless warning your TCP/IP stack may display that
1373 <application>Privoxy</application> is still running).
1377 <sect2 id="start-gentoo">
1378 <title>Gentoo</title>
1380 A script is again used. It will use the file <filename>/etc/privoxy/config
1381 </filename> as its main configuration file.
1385 /etc/init.d/privoxy start
1389 Note that <application>Privoxy</application> is not automatically started at
1390 boot time by default. You can change this with the <literal>rc-update</literal>
1395 rc-update add privoxy default
1403 See the section <link linkend="cmdoptions">Command line options</link> for
1407 must find a better place for this paragraph
1410 The included default configuration files should give a reasonable starting
1411 point. Most of the per site configuration is done in the
1412 <ulink url="actions-file.html"><quote>actions</quote></ulink> files. These are
1413 where various cookie actions are defined, ad and banner blocking, and other
1414 aspects of <application>Privoxy</application> configuration. There are several
1415 such files included, with varying levels of aggressiveness.
1419 You will probably want to keep an eye out for sites for which you may prefer
1420 persistent cookies, and add these to your actions configuration as needed. By
1421 default, most of these will be accepted only during the current browser
1422 session (aka <quote>session cookies</quote>), unless you add them to the
1423 configuration. If you want the browser to handle this instead, you will need
1424 to edit <filename>user.action</filename> (or through the web based interface)
1425 and disable this feature. If you use more than one browser, it would make
1426 more sense to let <application>Privoxy</application> handle this. In which
1427 case, the browser(s) should be set to accept all cookies.
1431 Another feature where you will probably want to define exceptions for trusted
1432 sites is the popup-killing (through the <ulink
1433 url="actions-file.html#KILL-POPUPS"><quote>+kill-popups</quote></ulink> and
1435 url="actions-file.html#FILTER-POPUPS"><quote>+filter{popups}</quote></ulink>
1436 actions), because your favorite shopping, banking, or leisure site may need
1437 popups (explained below).
1441 <application>Privoxy</application> does not support all of the optional HTTP/1.1
1442 features yet. In the unlikely event that you experience inexplicable problems
1443 with browsers that use HTTP/1.1 per default
1444 (like <application>Mozilla</application> or recent versions of I.E.), you might
1445 try to force HTTP/1.0 compatibility. For Mozilla, look under <literal>Edit ->
1446 Preferences -> Debug -> Networking</literal>.
1447 Alternatively, set the <quote>+downgrade-http-version</quote> config option in
1448 <filename>default.action</filename> which will downgrade your browser's HTTP
1449 requests from HTTP/1.1 to HTTP/1.0 before processing them.
1453 After running <application>Privoxy</application> for a while, you can
1454 start to fine tune the configuration to suit your personal, or site,
1455 preferences and requirements. There are many, many aspects that can
1456 be customized. <quote>Actions</quote>
1457 can be adjusted by pointing your browser to
1458 <ulink url="http://config.privoxy.org/">http://config.privoxy.org/</ulink>
1459 (shortcut: <ulink url="http://p.p/">http://p.p/</ulink>),
1460 and then follow the link to <quote>View & Change the Current Configuration</quote>.
1461 (This is an internal page and does not require Internet access.)
1465 In fact, various aspects of <application>Privoxy</application>
1466 configuration can be viewed from this page, including
1467 current configuration parameters, source code version numbers,
1468 the browser's request headers, and <quote>actions</quote> that apply
1469 to a given URL. In addition to the actions file
1470 editor mentioned above, <application>Privoxy</application> can also
1471 be turned <quote>on</quote> and <quote>off</quote> (toggled) from this page.
1475 If you encounter problems, try loading the page without
1476 <application>Privoxy</application>. If that helps, enter the URL where
1477 you have the problems into <ulink url="http://p.p/show-url-info">the browser
1478 based rule tracing utility</ulink>. See which rules apply and why, and
1479 then try turning them off for that site one after the other, until the problem
1480 is gone. When you have found the culprit, you might want to turn the rest on
1485 If the above paragraph sounds gibberish to you, you might want to <link
1486 linkend="actions-file">read more about the actions concept</link>
1487 or even dive deep into the <link linkend="actionsanat">Appendix
1492 If you can't get rid of the problem at all, think you've found a bug in
1493 Privoxy, want to propose a new feature or smarter rules, please see the
1494 section <link linkend="contact"><quote>Contacting the
1495 Developers</quote></link> below.
1500 <!-- ~~~~~ New section ~~~~~ -->
1501 <sect2 id="cmdoptions">
1502 <title>Command Line Options</title>
1504 <application>Privoxy</application> may be invoked with the following
1505 command-line options:
1513 <emphasis>--version</emphasis>
1516 Print version info and exit. Unix only.
1521 <emphasis>--help</emphasis>
1524 Print short usage info and exit. Unix only.
1529 <emphasis>--no-daemon</emphasis>
1532 Don't become a daemon, i.e. don't fork and become process group
1533 leader, and don't detach from controlling tty. Unix only.
1538 <emphasis>--pidfile FILE</emphasis>
1541 On startup, write the process ID to <emphasis>FILE</emphasis>. Delete the
1542 <emphasis>FILE</emphasis> on exit. Failure to create or delete the
1543 <emphasis>FILE</emphasis> is non-fatal. If no <emphasis>FILE</emphasis>
1544 option is given, no PID file will be used. Unix only.
1549 <emphasis>--user USER[.GROUP]</emphasis>
1552 After (optionally) writing the PID file, assume the user ID of
1553 <emphasis>USER</emphasis>, and if included the GID of GROUP. Exit if the
1554 privileges are not sufficient to do so. Unix only.
1559 <emphasis>--chroot</emphasis>
1562 Before changing to the user ID given in the <emphasis>--user</emphasis> option,
1563 chroot to that user's home directory, i.e. make the kernel pretend to the &my-app;
1564 process that the directory tree starts there. If set up carefully, this can limit
1565 the impact of possible vulnerabilities in &my-app; to the files contained in that hierarchy.
1571 <emphasis>--pre-chroot-nslookup hostname</emphasis>
1574 Specifies a hostname to look up before doing a chroot. On some systems, initializing the
1575 resolver library involves reading config files from /etc and/or loading additional shared
1576 libraries from /lib. On these systems, doing a hostname lookup before the chroot reduces
1577 the number of files that must be copied into the chroot tree.
1580 For fastest startup speed, a good value is a hostname that is not in /etc/hosts but that
1581 your local name server (listed in /etc/resolv.conf) can resolve without recursion
1582 (that is, without having to ask any other name servers). The hostname need not exist,
1583 but if it doesn't, an error message (which can be ignored) will be output.
1589 <emphasis>configfile</emphasis>
1592 If no <emphasis>configfile</emphasis> is included on the command line,
1593 <application>Privoxy</application> will look for a file named
1594 <quote>config</quote> in the current directory (except on Win32
1595 where it will look for <quote>config.txt</quote> instead). Specify
1596 full path to avoid confusion. If no config file is found,
1597 <application>Privoxy</application> will fail to start.
1605 On <application>MS Windows</application> only there are two additional
1606 command-line options to allow <application>Privoxy</application> to install and
1607 run as a <emphasis>service</emphasis>. See the
1608 <link linkend="installation-pack-win">Window Installation section</link>
1616 <!-- ~ End section ~ -->
1619 <!-- ~~~~~ New section ~~~~~ -->
1620 <sect1 id="configuration"><title>Privoxy Configuration</title>
1622 All <application>Privoxy</application> configuration is stored
1623 in text files. These files can be edited with a text editor.
1624 Many important aspects of <application>Privoxy</application> can
1625 also be controlled easily with a web browser.
1629 <!-- ~~~~~ New section ~~~~~ -->
1632 <title>Controlling Privoxy with Your Web Browser</title>
1634 <application>Privoxy</application>'s user interface can be reached through the special
1635 URL <ulink url="http://config.privoxy.org/">http://config.privoxy.org/</ulink>
1636 (shortcut: <ulink url="http://p.p/">http://p.p/</ulink>),
1637 which is a built-in page and works without Internet access.
1638 You will see the following section:
1642 <!-- Needs to be put in a table and colorized -->
1645 <bridgehead renderas="sect2"> Privoxy Menu</bridgehead>
1649 ▪ <ulink url="http://config.privoxy.org/show-status">View & change the current configuration</ulink>
1652 ▪ <ulink url="http://config.privoxy.org/show-version">View the source code version numbers</ulink>
1655 ▪ <ulink url="http://config.privoxy.org/show-request">View the request headers.</ulink>
1658 ▪ <ulink url="http://config.privoxy.org/show-url-info">Look up which actions apply to a URL and why</ulink>
1661 ▪ <ulink url="http://config.privoxy.org/toggle">Toggle Privoxy on or off</ulink>
1664 ▪ <ulink url="http://www.privoxy.org/
1665 &p-version;/user-manual/">Documentation</ulink>
1673 This should be self-explanatory. Note the first item leads to an editor for the
1674 <link linkend="actions-file">actions files</link>, which is where the ad, banner,
1675 cookie, and URL blocking magic is configured as well as other advanced features of
1676 <application>Privoxy</application>. This is an easy way to adjust various
1677 aspects of <application>Privoxy</application> configuration. The actions
1678 file, and other configuration files, are explained in detail below.
1682 <quote>Toggle Privoxy On or Off</quote> is handy for sites that might
1683 have problems with your current actions and filters. You can in fact use
1684 it as a test to see whether it is <application>Privoxy</application>
1685 causing the problem or not. <application>Privoxy</application> continues
1686 to run as a proxy in this case, but all manipulation is disabled, i.e.
1687 <application>Privoxy</application> acts like a normal forwarding proxy. There
1688 is even a toggle <link linkend="bookmarklets">Bookmarklet</link> offered, so
1689 that you can toggle <application>Privoxy</application> with one click from
1694 Note that several of the features described above are disabled by default
1695 in <application>Privoxy</application> 3.0.7 beta and later.
1697 <ulink url="config.html">configuration file</ulink> to learn why
1698 and in which cases it's safe to enable them again.
1703 <!-- ~ End section ~ -->
1708 <!-- ~~~~~ New section ~~~~~ -->
1710 <sect2 id="confoverview">
1711 <title>Configuration Files Overview</title>
1713 For Unix, *BSD and Linux, all configuration files are located in
1714 <filename>/etc/privoxy/</filename> by default. For MS Windows, OS/2, and
1715 AmigaOS these are all in the same directory as the
1716 <application>Privoxy</application> executable. <![%p-not-stable;[ The name
1717 and number of configuration files has changed from previous versions, and is
1718 subject to change as development progresses.]]>
1722 The installed defaults provide a reasonable starting point, though
1723 some settings may be aggressive by some standards. For the time being, the
1724 principle configuration files are:
1732 The <link linkend="config">main configuration file</link> is named <filename>config</filename>
1733 on Linux, Unix, BSD, OS/2, and AmigaOS and <filename>config.txt</filename>
1734 on Windows. This is a required file.
1740 <filename>default.action</filename> (the main <link linkend="actions-file">actions file</link>)
1741 is used to define which <quote>actions</quote> relating to banner-blocking, images, pop-ups,
1742 content modification, cookie handling etc should be applied by default. It also defines many
1743 exceptions (both positive and negative) from this default set of actions that enable
1744 <application>Privoxy</application> to selectively eliminate the junk, and only the junk, on
1745 as many websites as possible.
1748 Multiple actions files may be defined in <filename>config</filename>. These
1749 are processed in the order they are defined. Local customizations and locally
1750 preferred exceptions to the default policies as defined in
1751 <filename>default.action</filename> (which you will most probably want
1752 to define sooner or later) are probably best applied in
1753 <filename>user.action</filename>, where you can preserve them across
1754 upgrades. <filename>standard.action</filename> is only for
1755 <application>Privoxy's</application> internal use.
1758 There is also a web based editor that can be accessed from
1760 url="http://config.privoxy.org/show-status">http://config.privoxy.org/show-status</ulink>
1762 url="http://p.p/show-status">http://p.p/show-status</ulink>) for the
1763 various actions files.
1769 <quote>Filter files</quote> (the <link linkend="filter-file">filter
1770 file</link>) can be used to re-write the raw page content, including
1771 viewable text as well as embedded HTML and JavaScript, and whatever else
1772 lurks on any given web page. The filtering jobs are only pre-defined here;
1773 whether to apply them or not is up to the actions files.
1774 <filename>default.filter</filename> includes various filters made
1775 available for use by the developers. Some are much more intrusive than
1776 others, and all should be used with caution. You may define additional
1777 filter files in <filename>config</filename> as you can with
1778 actions files. We suggest <filename>user.filter</filename> for any
1779 locally defined filters or customizations.
1787 The syntax of the configuration and filter files may change between different
1788 Privoxy versions, unfortunately some enhancements cost backwards compatibility.
1789 <!-- Add link to documentation-->
1793 All files use the <quote><literal>#</literal></quote> character to denote a
1794 comment (the rest of the line will be ignored) and understand line continuation
1795 through placing a backslash ("<literal>\</literal>") as the very last character
1796 in a line. If the <literal>#</literal> is preceded by a backslash, it looses
1797 its special function. Placing a <literal>#</literal> in front of an otherwise
1798 valid configuration line to prevent it from being interpreted is called "commenting
1799 out" that line. Blank lines are ignored.
1803 The actions files and filter files
1804 can use Perl style <link linkend="regex">regular expressions</link> for
1805 maximum flexibility.
1809 After making any changes, there is no need to restart
1810 <application>Privoxy</application> in order for the changes to take
1811 effect. <application>Privoxy</application> detects such changes
1812 automatically. Note, however, that it may take one or two additional
1813 requests for the change to take effect. When changing the listening address
1814 of <application>Privoxy</application>, these <quote>wake up</quote> requests
1815 must obviously be sent to the <emphasis>old</emphasis> listening address.
1820 While under development, the configuration content is subject to change.
1821 The below documentation may not be accurate by the time you read this.
1822 Also, what constitutes a <quote>default</quote> setting, may change, so
1823 please check all your configuration files on important issues.
1829 <!-- ~ End section ~ -->
1832 <!-- ~~~~~~~~ New section Header ~~~~~~~~~ -->
1834 <!-- **************************************************** -->
1835 <!-- Include config.sgml here -->
1836 <!-- This is where the entire config file is detailed. -->
1838 <!-- end include -->
1841 <!-- ~ End section ~ -->
1845 <!-- ~~~~~~~~ New section Header ~~~~~~~~~ -->
1847 <sect1 id="actions-file"><title>Actions Files</title>
1850 The actions files are used to define what <emphasis>actions</emphasis>
1851 <application>Privoxy</application> takes for which URLs, and thus determines
1852 how ad images, cookies and various other aspects of HTTP content and
1853 transactions are handled, and on which sites (or even parts thereof).
1854 There are a number of such actions, with a wide range of functionality.
1855 Each action does something a little different.
1856 These actions give us a veritable arsenal of tools with which to exert
1857 our control, preferences and independence. Actions can be combined so that
1858 their effects are aggregated when applied against a given set of URLs.
1862 are three action files included with <application>Privoxy</application> with
1870 <filename>default.action</filename> - is the primary action file
1871 that sets the initial values for all actions. It is intended to
1872 provide a base level of functionality for
1873 <application>Privoxy's</application> array of features. So it is
1874 a set of broad rules that should work reasonably well as-is for most users.
1875 This is the file that the developers are keeping updated, and <link
1876 linkend="installation-keepupdated">making available to users</link>.
1877 The user's preferences as set in <filename>standard.action</filename>,
1878 e.g. either <literal>Cautious</literal> (the default),
1879 <literal>Medium</literal>, or <literal>Advanced</literal> (see
1885 <filename>user.action</filename> - is intended to be for local site
1886 preferences and exceptions. As an example, if your ISP or your bank
1887 has specific requirements, and need special handling, this kind of
1888 thing should go here. This file will not be upgraded.
1893 <filename>standard.action</filename> - is used only by the web based editor
1894 at <ulink url="http://config.privoxy.org/edit-actions-list?f=default">
1895 http://config.privoxy.org/edit-actions-list?f=default</ulink>,
1896 to set various pre-defined sets of rules for the default actions section
1897 in <filename>default.action</filename>.
1900 <guibutton>Edit</guibutton> <guibutton>Set to Cautious</guibutton> <guibutton>Set to Medium</guibutton> <guibutton>Set to Advanced</guibutton>
1903 These have increasing levels of aggressiveness <emphasis>and have no
1904 influence on your browsing unless you select them explicitly in the
1905 editor</emphasis>. A default installation should be pre-set to
1906 <literal>Cautious</literal> (versions prior to 3.0.5 were set to
1907 <literal>Medium</literal>). New users should try this for a while before
1908 adjusting the settings to more aggressive levels. The more aggressive
1909 the settings, then the more likelihood there is of problems such as sites
1910 not working as they should.
1913 The <guibutton>Edit</guibutton> button allows you to turn each
1914 action on/off individually for fine-tuning. The <guibutton>Cautious</guibutton>
1915 button changes the actions list to low/safe settings which will activate
1916 ad blocking and a minimal set of &my-app;'s features, and subsequently
1917 there will be less of a chance for accidental problems. The
1918 <guibutton>Medium</guibutton> button sets the list to a medium level of
1919 other features and a low level set of privacy features. The
1920 <guibutton>Advanced</guibutton> button sets the list to a high level of
1921 ad blocking and medium level of privacy. See the chart below. The latter
1922 three buttons over-ride any changes via with the
1923 <guibutton>Edit</guibutton> button. More fine-tuning can be done in the
1924 lower sections of this internal page.
1927 It is not recommend to edit the <filename>standard.action</filename> file
1931 The default profiles, and their associated actions, as pre-defined in
1932 <filename>standard.action</filename> are<!-- different than this table which is out of date -->:
1935 <table frame=all><title>Default Configurations</title>
1936 <tgroup cols=4 align=left colsep=1 rowsep=1>
1937 <colspec colname=c1>
1938 <colspec colname=c2>
1939 <colspec colname=c3>
1940 <colspec colname=c4>
1943 <entry>Feature</entry>
1944 <entry>Cautious</entry>
1945 <entry>Medium</entry>
1946 <entry>Advanced</entry>
1951 <!-- <entry>f1</entry> -->
1952 <!-- <entry>f2</entry> -->
1953 <!-- <entry>f3</entry> -->
1954 <!-- <entry>f4</entry> -->
1960 <entry>Ad-blocking Aggressiveness</entry>
1961 <entry>medium</entry>
1967 <entry>Ad-filtering by size</entry>
1974 <entry>Ad-filtering by link</entry>
1980 <entry>Pop-up killing</entry>
1981 <entry>blocks only</entry>
1982 <entry>blocks only</entry>
1983 <entry>blocks only</entry>
1987 <entry>Privacy Features</entry>
1989 <entry>medium</entry>
1990 <entry>medium/high</entry>
1994 <entry>Cookie handling</entry>
1996 <entry>session-only</entry>
2001 <entry>Referer forging</entry>
2009 <entry>GIF de-animation</entry>
2017 <entry>Fast redirects</entry>
2024 <entry>HTML taming</entry>
2031 <entry>JavaScript taming</entry>
2038 <entry>Web-bug killing</entry>
2045 <entry>Image tag reordering</entry>
2061 The list of actions files to be used are defined in the main configuration
2062 file, and are processed in the order they are defined (e.g.
2063 <filename>default.action</filename> is typically processed before
2064 <filename>user.action</filename>). The content of these can all be viewed and
2066 url="http://config.privoxy.org/show-status">http://config.privoxy.org/show-status</ulink>.
2067 The over-riding principle when applying actions, is that the last action that
2068 matches a given URL wins. The broadest, most general rules go first
2069 (defined in <filename>default.action</filename>),
2070 followed by any exceptions (typically also in
2071 <filename>default.action</filename>), which are then followed lastly by any
2072 local preferences (typically in <emphasis>user</emphasis><filename>.action</filename>).
2073 Generally, <filename>user.action</filename> has the last word.
2077 An actions file typically has multiple sections. If you want to use
2078 <quote>aliases</quote> in an actions file, you have to place the (optional)
2079 <link linkend="aliases">alias section</link> at the top of that file.
2080 Then comes the default set of rules which will apply universally to all
2081 sites and pages (be <emphasis>very careful</emphasis> with using such a
2082 universal set in <filename>user.action</filename> or any other actions file after
2083 <filename>default.action</filename>, because it will override the result
2084 from consulting any previous file). And then below that,
2085 exceptions to the defined universal policies. You can regard
2086 <filename>user.action</filename> as an appendix to <filename>default.action</filename>,
2087 with the advantage that it is a separate file, which makes preserving your
2088 personal settings across <application>Privoxy</application> upgrades easier.
2092 Actions can be used to block anything you want, including ads, banners, or
2093 just some obnoxious URL whose content you would rather not see. Cookies can be accepted
2094 or rejected, or accepted only during the current browser session (i.e. not
2095 written to disk), content can be modified, some JavaScripts tamed, user-tracking
2096 fooled, and much more. See below for a <link linkend="actions">complete list
2100 <!-- ~~~~~ New section ~~~~~ -->
2102 <title>Finding the Right Mix</title>
2104 Note that some <link linkend="actions">actions</link>, like cookie suppression
2105 or script disabling, may render some sites unusable that rely on these
2106 techniques to work properly. Finding the right mix of actions is not always easy and
2107 certainly a matter of personal taste. And, things can always change, requiring
2108 refinements in the configuration. In general, it can be said that the more
2109 <quote>aggressive</quote> your default settings (in the top section of the
2110 actions file) are, the more exceptions for <quote>trusted</quote> sites you
2111 will have to make later. If, for example, you want to crunch all cookies per
2112 default, you'll have to make exceptions from that rule for sites that you
2113 regularly use and that require cookies for actually useful purposes, like maybe
2114 your bank, favorite shop, or newspaper.
2118 We have tried to provide you with reasonable rules to start from in the
2119 distribution actions files. But there is no general rule of thumb on these
2120 things. There just are too many variables, and sites are constantly changing.
2121 Sooner or later you will want to change the rules (and read this chapter again :).
2125 <!-- ~~~~~ New section ~~~~~ -->
2127 <title>How to Edit</title>
2129 The easiest way to edit the actions files is with a browser by
2130 using our browser-based editor, which can be reached from <ulink
2131 url="http://config.privoxy.org/show-status">http://config.privoxy.org/show-status</ulink>.
2132 Note: the config file option <link
2133 linkend="enable-edit-actions">enable-edit-actions</link> must be enabled for
2134 this to work. The editor allows both fine-grained control over every single
2135 feature on a per-URL basis, and easy choosing from wholesale sets of defaults
2136 like <quote>Cautious</quote>, <quote>Medium</quote> or
2137 <quote>Advanced</quote>. Warning: the <quote>Advanced</quote> setting is more
2138 aggressive, and will be more likely to cause problems for some sites.
2139 Experienced users only!
2143 If you prefer plain text editing to GUIs, you can of course also directly edit the
2144 the actions files with your favorite text editor. Look at
2145 <filename>default.action</filename> which is richly commented with many
2151 <sect2 id="actions-apply">
2152 <title>How Actions are Applied to Requests</title>
2154 Actions files are divided into sections. There are special sections,
2155 like the <quote><link linkend="aliases">alias</link></quote> sections which will
2156 be discussed later. For now let's concentrate on regular sections: They have a
2157 heading line (often split up to multiple lines for readability) which consist
2158 of a list of actions, separated by whitespace and enclosed in curly braces.
2159 Below that, there is a list of URL and tag patterns, each on a separate line.
2163 To determine which actions apply to a request, the URL of the request is
2164 compared to all URL patterns in each <quote>action file</quote>.
2165 Every time it matches, the list of applicable actions for the request is
2166 incrementally updated, using the heading of the section in which the
2167 pattern is located. The same is done again for tags and tag patterns later on.
2171 If multiple applying sections set the same action differently,
2172 the last match wins. If not, the effects are aggregated.
2173 E.g. a URL might match a regular section with a heading line of <literal>{
2174 +<link linkend="handle-as-image">handle-as-image</link> }</literal>,
2175 then later another one with just <literal>{
2176 +<link linkend="block">block</link> }</literal>, resulting
2177 in <emphasis>both</emphasis> actions to apply. And there may well be
2178 cases where you will want to combine actions together. Such a section then
2184 { +<literal>handle-as-image</literal> +<literal>block</literal> }
2185 # Block these as if they were images. Send no block page.
2187 media.example.com/.*banners
2188 .example.com/images/ads/</screen>
2192 You can trace this process for URL patterns and any given URL by visiting <ulink
2193 url="http://config.privoxy.org/show-url-info">http://config.privoxy.org/show-url-info</ulink>.
2197 Examples and more detail on this is provided in the Appendix, <link linkend="ACTIONSANAT">
2198 Troubleshooting: Anatomy of an Action</link> section.
2202 <!-- ~~~~~ New section ~~~~~ -->
2203 <sect2 id="af-patterns">
2204 <title>Patterns</title>
2206 As mentioned, <application>Privoxy</application> uses <quote>patterns</quote>
2207 to determine what <emphasis>actions</emphasis> might apply to which sites and
2208 pages your browser attempts to access. These <quote>patterns</quote> use wild
2209 card type <emphasis>pattern</emphasis> matching to achieve a high degree of
2210 flexibility. This allows one expression to be expanded and potentially match
2211 against many similar patterns.
2215 Generally, an URL pattern has the form
2216 <literal><domain>/<path></literal>, where both the
2217 <literal><domain></literal> and <literal><path></literal> are
2218 optional. (This is why the special <literal>/</literal> pattern matches all
2219 URLs). Note that the protocol portion of the URL pattern (e.g.
2220 <literal>http://</literal>) should <emphasis>not</emphasis> be included in
2221 the pattern. This is assumed already!
2224 The pattern matching syntax is different for the domain and path parts of
2225 the URL. The domain part uses a simple globbing type matching technique,
2226 while the path part uses a more flexible
2227 <ulink url="http://en.wikipedia.org/wiki/Regular_expressions"><quote>Regular
2228 Expressions (PCRE)</quote></ulink> based syntax.
2233 <term><literal>www.example.com/</literal></term>
2236 is a domain-only pattern and will match any request to <literal>www.example.com</literal>,
2237 regardless of which document on that server is requested. So ALL pages in
2238 this domain would be covered by the scope of this action. Note that a
2239 simple <literal>example.com</literal> is different and would NOT match.
2244 <term><literal>www.example.com</literal></term>
2247 means exactly the same. For domain-only patterns, the trailing <literal>/</literal> may
2253 <term><literal>www.example.com/index.html$</literal></term>
2256 matches all the documents on <literal>www.example.com</literal>
2257 whose name starts with <literal>/index.html</literal>.
2262 <term><literal>www.example.com/index.html$</literal></term>
2265 matches only the single document <literal>/index.html</literal>
2266 on <literal>www.example.com</literal>.
2271 <term><literal>/index.html$</literal></term>
2274 matches the document <literal>/index.html</literal>, regardless of the domain,
2275 i.e. on <emphasis>any</emphasis> web server anywhere.
2280 <term><literal>index.html</literal></term>
2283 matches nothing, since it would be interpreted as a domain name and
2284 there is no top-level domain called <literal>.html</literal>. So its
2292 <!-- ~~~~~ New section ~~~~~ -->
2293 <sect3><title>The Domain Pattern</title>
2296 The matching of the domain part offers some flexible options: if the
2297 domain starts or ends with a dot, it becomes unanchored at that end.
2303 <term><literal>.example.com</literal></term>
2306 matches any domain with first-level domain <literal>com</literal>
2307 and second-level domain <literal>example</literal>.
2308 For example <literal>www.example.com</literal>,
2309 <literal>example.com</literal> and <literal>foo.bar.baz.example.com</literal>.
2310 Note that it wouldn't match if the second-level domain was <literal>another-example</literal>.
2315 <term><literal>www.</literal></term>
2318 matches any domain that <emphasis>STARTS</emphasis> with
2319 <literal>www.</literal> (It also matches the domain
2320 <literal>www</literal> but most of the time that doesn't matter.)
2325 <term><literal>.example.</literal></term>
2328 matches any domain that <emphasis>CONTAINS</emphasis> <literal>.example.</literal>.
2329 And, by the way, also included would be any files or documents that exist
2330 within that domain since no path limitations are specified. (Correctly
2331 speaking: It matches any FQDN that contains <literal>example</literal> as
2332 a domain.) This might be <literal>www.example.com</literal>,
2333 <literal>news.example.de</literal>, or
2334 <literal>www.example.net/cgi/testing.pl</literal> for instance. All these
2342 Additionally, there are wild-cards that you can use in the domain names
2343 themselves. These work similarly to shell globbing type wild-cards:
2344 <quote>*</quote> represents zero or more arbitrary characters (this is
2346 <ulink url="http://en.wikipedia.org/wiki/Regular_expressions"><quote>Regular
2347 Expression</quote></ulink> based syntax of <quote>.*</quote>),
2348 <quote>?</quote> represents any single character (this is equivalent to the
2349 regular expression syntax of a simple <quote>.</quote>), and you can define
2350 <quote>character classes</quote> in square brackets which is similar to
2351 the same regular expression technique. All of this can be freely mixed:
2356 <term><literal>ad*.example.com</literal></term>
2359 matches <quote>adserver.example.com</quote>,
2360 <quote>ads.example.com</quote>, etc but not <quote>sfads.example.com</quote>
2365 <term><literal>*ad*.example.com</literal></term>
2368 matches all of the above, and then some.
2373 <term><literal>.?pix.com</literal></term>
2376 matches <literal>www.ipix.com</literal>,
2377 <literal>pictures.epix.com</literal>, <literal>a.b.c.d.e.upix.com</literal> etc.
2382 <term><literal>www[1-9a-ez].example.c*</literal></term>
2385 matches <literal>www1.example.com</literal>,
2386 <literal>www4.example.cc</literal>, <literal>wwwd.example.cy</literal>,
2387 <literal>wwwz.example.com</literal> etc., but <emphasis>not</emphasis>
2388 <literal>wwww.example.com</literal>.
2395 While flexible, this is not the sophistication of full regular expression based syntax.
2400 <!-- ~ End section ~ -->
2403 <!-- ~~~~~ New section ~~~~~ -->
2404 <sect3><title>The Path Pattern</title>
2407 <application>Privoxy</application> uses Perl compatible (PCRE)
2408 <ulink url="http://en.wikipedia.org/wiki/Regular_expressions"><quote>Regular
2409 Expression</quote></ulink> based syntax
2410 (through the <ulink url="http://www.pcre.org/">PCRE</ulink> library) for
2411 matching the path portion (after the slash), and is thus more flexible.
2415 There is an <link linkend="regex">Appendix</link> with a brief quick-start into regular
2416 expressions, and full (very technical) documentation on PCRE regex syntax is available on-line
2417 at <ulink url="http://www.pcre.org/man.txt">http://www.pcre.org/man.txt</ulink>.
2418 You might also find the Perl man page on regular expressions (<literal>man perlre</literal>)
2419 useful, which is available on-line at <ulink
2420 url="http://perldoc.perl.org/perlre.html">http://perldoc.perl.org/perlre.html</ulink>.
2424 Note that the path pattern is automatically left-anchored at the <quote>/</quote>,
2425 i.e. it matches as if it would start with a <quote>^</quote> (regular expression speak
2426 for the beginning of a line).
2430 Please also note that matching in the path is <emphasis>CASE INSENSITIVE</emphasis>
2431 by default, but you can switch to case sensitive at any point in the pattern by using the
2432 <quote>(?-i)</quote> switch: <literal>www.example.com/(?-i)PaTtErN.*</literal> will match
2433 only documents whose path starts with <literal>PaTtErN</literal> in
2434 <emphasis>exactly</emphasis> this capitalization.
2439 <term><literal>.example.com/.*</literal></term>
2442 Is equivalent to just <quote>.example.com</quote>, since any documents
2443 within that domain are matched with or without the <quote>.*</quote>
2444 regular expression. This is redundant
2449 <term><literal>.example.com/.*/index.html$</literal></term>
2452 Will match any page in the domain of <quote>example.com</quote> that is
2453 named <quote>index.html</quote>, and that is part of some path. For
2454 example, it matches <quote>www.example.com/testing/index.html</quote> but
2455 NOT <quote>www.example.com/index.html</quote> because the regular
2456 expression called for at least two <quote>/'s</quote>, thus the path
2457 requirement. It also would match
2458 <quote>www.example.com/testing/index_html</quote>, because of the
2459 special meta-character <quote>.</quote>.
2464 <term><literal>.example.com/(.*/)?index\.html$</literal></term>
2467 This regular expression is conditional so it will match any page
2468 named <quote>index.html</quote> regardless of path which in this case can
2469 have one or more <quote>/'s</quote>. And this one must contain exactly
2470 <quote>.html</quote> (but does not have to end with that!).
2475 <term><literal>.example.com/(.*/)(ads|banners?|junk)</literal></term>
2478 This regular expression will match any path of <quote>example.com</quote>
2479 that contains any of the words <quote>ads</quote>, <quote>banner</quote>,
2480 <quote>banners</quote> (because of the <quote>?</quote>) or <quote>junk</quote>.
2481 The path does not have to end in these words, just contain them.
2486 <term><literal>.example.com/(.*/)(ads|banners?|junk)/.*\.(jpe?g|gif|png)$</literal></term>
2489 This is very much the same as above, except now it must end in either
2490 <quote>.jpg</quote>, <quote>.jpeg</quote>, <quote>.gif</quote> or <quote>.png</quote>. So this
2491 one is limited to common image formats.
2498 There are many, many good examples to be found in <filename>default.action</filename>,
2499 and more tutorials below in <link linkend="regex">Appendix on regular expressions</link>.
2504 <!-- ~ End section ~ -->
2507 <!-- ~~~~~ New section ~~~~~ -->
2508 <sect3 id="tag-pattern"><title>The Tag Pattern</title>
2511 Tag patterns are used to change the applying actions based on the
2512 request's tags. Tags can be created with either the
2513 <link linkend="CLIENT-HEADER-TAGGER">client-header-tagger</link>
2514 or the <link linkend="SERVER-HEADER-TAGGER">server-header-tagger</link> action.
2518 Tag patterns have to start with <quote>TAG:</quote>, so &my-app;
2519 can tell them apart from URL patterns. Everything after the colon
2520 including white space, is interpreted as a regular expression with
2521 path pattern syntax, except that tag patterns aren't left-anchored
2522 automatically (&my-app; doesn't silently add a <quote>^</quote>,
2523 you have to do it yourself if you need it).
2527 To match all requests that are tagged with <quote>foo</quote>
2528 your pattern line should be <quote>TAG:^foo$</quote>,
2529 <quote>TAG:foo</quote> would work as well, but it would also
2530 match requests whose tags contain <quote>foo</quote> somewhere.
2531 <quote>TAG: foo</quote> wouldn't work as it requires white space.
2535 Sections can contain URL and tag patterns at the same time,
2536 but tag patterns are checked after the URL patterns and thus
2537 always overrule them, even if they are located before the URL patterns.
2541 Once a new tag is added, Privoxy checks right away if it's matched by one
2542 of the tag patterns and updates the action settings accordingly. As a result
2543 tags can be used to activate other tagger actions, as long as these other
2544 taggers look for headers that haven't already be parsed.
2548 For example you could tag client requests which use the
2549 <literal>POST</literal> method,
2550 then use this tag to activate another tagger that adds a tag if cookies
2551 are sent, and then use a block action based on the cookie tag. This allows
2552 the outcome of one action, to be input into a subsequent action. However if
2553 you'd reverse the position of the described taggers, and activated the
2554 method tagger based on the cookie tagger, no method tags would be created.
2555 The method tagger would look for the request line, but at the time
2556 the cookie tag is created, the request line has already been parsed.
2560 While this is a limitation you should be aware of, this kind of
2561 indirection is seldom needed anyway and even the example doesn't
2562 make too much sense.
2569 <!-- ~ End section ~ -->
2572 <!-- ~~~~~ New section ~~~~~ -->
2574 <sect2 id="actions">
2575 <title>Actions</title>
2577 All actions are disabled by default, until they are explicitly enabled
2578 somewhere in an actions file. Actions are turned on if preceded with a
2579 <quote>+</quote>, and turned off if preceded with a <quote>-</quote>. So a
2580 <literal>+action</literal> means <quote>do that action</quote>, e.g.
2581 <literal>+block</literal> means <quote>please block URLs that match the
2582 following patterns</quote>, and <literal>-block</literal> means <quote>don't
2583 block URLs that match the following patterns, even if <literal>+block</literal>
2584 previously applied.</quote>
2589 Again, actions are invoked by placing them on a line, enclosed in curly braces and
2590 separated by whitespace, like in
2591 <literal>{+some-action -some-other-action{some-parameter}}</literal>,
2592 followed by a list of URL patterns, one per line, to which they apply.
2593 Together, the actions line and the following pattern lines make up a section
2594 of the actions file.
2598 Actions fall into three categories:
2605 Boolean, i.e the action can only be <quote>enabled</quote> or
2606 <quote>disabled</quote>. Syntax:
2610 +<replaceable class="function">name</replaceable> # enable action <replaceable class="parameter">name</replaceable>
2611 -<replaceable class="function">name</replaceable> # disable action <replaceable class="parameter">name</replaceable></screen>
2614 Example: <literal>+block</literal>
2621 Parameterized, where some value is required in order to enable this type of action.
2626 +<replaceable class="function">name</replaceable>{<replaceable class="parameter">param</replaceable>} # enable action and set parameter to <replaceable class="parameter">param</replaceable>,
2627 # overwriting parameter from previous match if necessary
2628 -<replaceable class="function">name</replaceable> # disable action. The parameter can be omitted</screen>
2631 Note that if the URL matches multiple positive forms of a parameterized action,
2632 the last match wins, i.e. the params from earlier matches are simply ignored.
2635 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>
2641 Multi-value. These look exactly like parameterized actions,
2642 but they behave differently: If the action applies multiple times to the
2643 same URL, but with different parameters, <emphasis>all</emphasis> the parameters
2644 from <emphasis>all</emphasis> matches are remembered. This is used for actions
2645 that can be executed for the same request repeatedly, like adding multiple
2646 headers, or filtering through multiple filters. Syntax:
2650 +<replaceable class="function">name</replaceable>{<replaceable class="parameter">param</replaceable>} # enable action and add <replaceable class="parameter">param</replaceable> to the list of parameters
2651 -<replaceable class="function">name</replaceable>{<replaceable class="parameter">param</replaceable>} # remove the parameter <replaceable class="parameter">param</replaceable> from the list of parameters
2652 # If it was the last one left, disable the action.
2653 <replaceable class="parameter">-name</replaceable> # disable this action completely and remove all parameters from the list</screen>
2656 Examples: <literal>+add-header{X-Fun-Header: Some text}</literal> and
2657 <literal>+filter{html-annoyances}</literal>
2665 If nothing is specified in any actions file, no <quote>actions</quote> are
2666 taken. So in this case <application>Privoxy</application> would just be a
2667 normal, non-blocking, non-filtering proxy. You must specifically enable the
2668 privacy and blocking features you need (although the provided default actions
2669 files will give a good starting point).
2673 Later defined action sections always over-ride earlier ones of the same type.
2674 So exceptions to any rules you make, should come in the latter part of the file (or
2675 in a file that is processed later when using multiple actions files such
2676 as <filename>user.action</filename>). For multi-valued actions, the actions
2677 are applied in the order they are specified. Actions files are processed in
2678 the order they are defined in <filename>config</filename> (the default
2679 installation has three actions files). It also quite possible for any given
2680 URL to match more than one <quote>pattern</quote> (because of wildcards and
2681 regular expressions), and thus to trigger more than one set of actions! Last
2685 <!-- start actions listing -->
2687 The list of valid <application>Privoxy</application> actions are:
2691 <!-- ********************************************************** -->
2692 <!-- Please note the below defined actions use id's that are -->
2693 <!-- probably linked from other places, so please don't change. -->
2695 <!-- ********************************************************** -->
2698 <!-- ~~~~~ New section ~~~~~ -->
2700 <sect3 renderas="sect4" id="add-header">
2701 <title>add-header</title>
2705 <term>Typical use:</term>
2707 <para>Confuse log analysis, custom applications</para>
2712 <term>Effect:</term>
2715 Sends a user defined HTTP header to the web server.
2722 <!-- boolean, parameterized, Multi-value -->
2724 <para>Multi-value.</para>
2729 <term>Parameter:</term>
2732 Any string value is possible. Validity of the defined HTTP headers is not checked.
2733 It is recommended that you use the <quote><literal>X-</literal></quote> prefix
2743 This action may be specified multiple times, in order to define multiple
2744 headers. This is rarely needed for the typical user. If you don't know what
2745 <quote>HTTP headers</quote> are, you definitely don't need to worry about this
2752 <term>Example usage:</term>
2755 <screen>+add-header{X-User-Tracking: sucks}</screen>
2763 <!-- ~~~~~ New section ~~~~~ -->
2764 <sect3 renderas="sect4" id="block">
2765 <title>block</title>
2769 <term>Typical use:</term>
2771 <para>Block ads or other unwanted content</para>
2776 <term>Effect:</term>
2779 Requests for URLs to which this action applies are blocked, i.e. the
2780 requests are trapped by &my-app; and the requested URL is never retrieved,
2781 but is answered locally with a substitute page or image, as determined by
2783 linkend="handle-as-image">handle-as-image</link></literal>,
2785 linkend="set-image-blocker">set-image-blocker</link></literal>, and
2787 linkend="handle-as-empty-document">handle-as-empty-document</link></literal> actions.
2795 <!-- boolean, parameterized, Multi-value -->
2797 <para>Boolean.</para>
2802 <term>Parameter:</term>
2812 <application>Privoxy</application> sends a special <quote>BLOCKED</quote> page
2813 for requests to blocked pages. This page contains links to find out why the request
2814 was blocked, and a click-through to the blocked content (the latter only if compiled with the
2815 force feature enabled). The <quote>BLOCKED</quote> page adapts to the available
2816 screen space -- it displays full-blown if space allows, or miniaturized and text-only
2817 if loaded into a small frame or window. If you are using <application>Privoxy</application>
2818 right now, you can take a look at the
2819 <ulink url="http://ads.bannerserver.example.com/nasty-ads/sponsor.html"><quote>BLOCKED</quote>
2823 A very important exception occurs if <emphasis>both</emphasis>
2824 <literal>block</literal> and <literal><link linkend="handle-as-image">handle-as-image</link></literal>,
2825 apply to the same request: it will then be replaced by an image. If
2826 <literal><link linkend="set-image-blocker">set-image-blocker</link></literal>
2827 (see below) also applies, the type of image will be determined by its parameter,
2828 if not, the standard checkerboard pattern is sent.
2831 It is important to understand this process, in order
2832 to understand how <application>Privoxy</application> deals with
2833 ads and other unwanted content. Blocking is a core feature, and one
2834 upon which various other features depend.
2837 The <literal><link linkend="filter">filter</link></literal>
2838 action can perform a very similar task, by <quote>blocking</quote>
2839 banner images and other content through rewriting the relevant URLs in the
2840 document's HTML source, so they don't get requested in the first place.
2841 Note that this is a totally different technique, and it's easy to confuse the two.
2847 <term>Example usage (section):</term>
2851 # Block and replace with "blocked" page
2852 .nasty-stuff.example.com
2854 {+block +handle-as-image}
2855 # Block and replace with image
2859 {+block +handle-as-empty-document}
2860 # Block and then ignore
2861 adserver.exampleclick.net/.*\.js$</screen>
2871 <!-- ~~~~~ New section ~~~~~ -->
2872 <sect3 renderas="sect4" id="client-header-filter">
2873 <title>client-header-filter</title>
2877 <term>Typical use:</term>
2880 Rewrite or remove single client headers.
2886 <term>Effect:</term>
2889 All client headers to which this action applies are filtered on-the-fly through
2890 the specified regular expression based substitutions.
2897 <!-- boolean, parameterized, Multi-value -->
2899 <para>Parameterized.</para>
2904 <term>Parameter:</term>
2907 The name of a client-header filter, as defined in one of the
2908 <link linkend="filter-file">filter files</link>.
2917 Client-header filters are applied to each header on its own, not to
2918 all at once. This makes it easier to diagnose problems, but on the downside
2919 you can't write filters that only change header x if header y's value is z.
2920 You can do that by using tags though.
2923 Client-header filters are executed after the other header actions have finished
2924 and use their output as input.
2927 If the request URL gets changed, &my-app; will detect that and use the new
2928 one. This can be used to rewrite the request destination behind the client's
2929 back, for example to specify a Tor exit relay for certain requests.
2932 Please refer to the <link linkend="filter-file">filter file chapter</link>
2933 to learn which client-header filters are available by default, and how to
2941 <term>Example usage (section):</term>
2945 # Hide Tor exit notation in Host and Referer Headers
2946 {+client-header-filter{hide-tor-exit-notation}}
2957 <!-- ~~~~~ New section ~~~~~ -->
2958 <sect3 renderas="sect4" id="client-header-tagger">
2959 <title>client-header-tagger</title>
2963 <term>Typical use:</term>
2966 Block requests based on their headers.
2972 <term>Effect:</term>
2975 Client headers to which this action applies are filtered on-the-fly through
2976 the specified regular expression based substitutions, the result is used as
2984 <!-- boolean, parameterized, Multi-value -->
2986 <para>Parameterized.</para>
2991 <term>Parameter:</term>
2994 The name of a client-header tagger, as defined in one of the
2995 <link linkend="filter-file">filter files</link>.
3004 Client-header taggers are applied to each header on its own,
3005 and as the header isn't modified, each tagger <quote>sees</quote>
3009 Client-header taggers are the first actions that are executed
3010 and their tags can be used to control every other action.
3016 <term>Example usage (section):</term>
3020 # Tag every request with the User-Agent header
3021 {+client-header-tagger{user-agent}}
3032 <!-- ~~~~~ New section ~~~~~ -->
3033 <sect3 renderas="sect4" id="content-type-overwrite">
3034 <title>content-type-overwrite</title>
3038 <term>Typical use:</term>
3040 <para>Stop useless download menus from popping up, or change the browser's rendering mode</para>
3045 <term>Effect:</term>
3048 Replaces the <quote>Content-Type:</quote> HTTP server header.
3055 <!-- Boolean, Parameterized, Multi-value -->
3057 <para>Parameterized.</para>
3062 <term>Parameter:</term>
3074 The <quote>Content-Type:</quote> HTTP server header is used by the
3075 browser to decide what to do with the document. The value of this
3076 header can cause the browser to open a download menu instead of
3077 displaying the document by itself, even if the document's format is
3078 supported by the browser.
3081 The declared content type can also affect which rendering mode
3082 the browser chooses. If XHTML is delivered as <quote>text/html</quote>,
3083 many browsers treat it as yet another broken HTML document.
3084 If it is send as <quote>application/xml</quote>, browsers with
3085 XHTML support will only display it, if the syntax is correct.
3088 If you see a web site that proudly uses XHTML buttons, but sets
3089 <quote>Content-Type: text/html</quote>, you can use &my-app;
3090 to overwrite it with <quote>application/xml</quote> and validate
3091 the web master's claim inside your XHTML-supporting browser.
3092 If the syntax is incorrect, the browser will complain loudly.
3095 You can also go the opposite direction: if your browser prints
3096 error messages instead of rendering a document falsely declared
3097 as XHTML, you can overwrite the content type with
3098 <quote>text/html</quote> and have it rendered as broken HTML document.
3101 By default <literal>content-type-overwrite</literal> only replaces
3102 <quote>Content-Type:</quote> headers that look like some kind of text.
3103 If you want to overwrite it unconditionally, you have to combine it with
3104 <literal><link linkend="force-text-mode">force-text-mode</link></literal>.
3105 This limitation exists for a reason, think twice before circumventing it.
3108 Most of the time it's easier to replace this action with a custom
3109 <literal><link linkend="server-header-filter">server-header filter</link></literal>.
3110 It allows you to activate it for every document of a certain site and it will still
3111 only replace the content types you aimed at.
3114 Of course you can apply <literal>content-type-overwrite</literal>
3115 to a whole site and then make URL based exceptions, but it's a lot
3116 more work to get the same precision.
3122 <term>Example usage (sections):</term>
3125 <screen># Check if www.example.net/ really uses valid XHTML
3126 { +content-type-overwrite{application/xml} }
3129 # but leave the content type unmodified if the URL looks like a style sheet
3130 {-content-type-overwrite}
3131 www.example.net/.*\.css$
3132 www.example.net/.*style
3141 <!-- ~~~~~ New section ~~~~~ -->
3142 <sect3 renderas="sect4" id="crunch-client-header">
3146 <title>crunch-client-header</title>
3150 <term>Typical use:</term>
3152 <para>Remove a client header <application>Privoxy</application> has no dedicated action for.</para>
3157 <term>Effect:</term>
3160 Deletes every header sent by the client that contains the string the user supplied as parameter.
3167 <!-- Boolean, Parameterized, Multi-value -->
3169 <para>Parameterized.</para>
3174 <term>Parameter:</term>
3186 This action allows you to block client headers for which no dedicated
3187 <application>Privoxy</application> action exists.
3188 <application>Privoxy</application> will remove every client header that
3189 contains the string you supplied as parameter.
3192 Regular expressions are <emphasis>not supported</emphasis> and you can't
3193 use this action to block different headers in the same request, unless
3194 they contain the same string.
3197 <literal>crunch-client-header</literal> is only meant for quick tests.
3198 If you have to block several different headers, or only want to modify
3199 parts of them, you should use a
3200 <literal><link linkend="client-header-filter">client-header filter</link></literal>.
3204 Don't block any header without understanding the consequences.
3211 <term>Example usage (section):</term>
3214 <screen># Block the non-existent "Privacy-Violation:" client header
3215 { +crunch-client-header{Privacy-Violation:} }
3225 <!-- ~~~~~ New section ~~~~~ -->
3226 <sect3 renderas="sect4" id="crunch-if-none-match">
3227 <title>crunch-if-none-match</title>
3233 <term>Typical use:</term>
3235 <para>Prevent yet another way to track the user's steps between sessions.</para>
3240 <term>Effect:</term>
3243 Deletes the <quote>If-None-Match:</quote> HTTP client header.
3250 <!-- Boolean, Parameterized, Multi-value -->
3252 <para>Boolean.</para>
3257 <term>Parameter:</term>
3269 Removing the <quote>If-None-Match:</quote> HTTP client header
3270 is useful for filter testing, where you want to force a real
3271 reload instead of getting status code <quote>304</quote> which
3272 would cause the browser to use a cached copy of the page.
3275 It is also useful to make sure the header isn't used as a cookie
3276 replacement (unlikely but possible).
3279 Blocking the <quote>If-None-Match:</quote> header shouldn't cause any
3280 caching problems, as long as the <quote>If-Modified-Since:</quote> header
3281 isn't blocked or missing as well.
3284 It is recommended to use this action together with
3285 <literal><link linkend="hide-if-modified-since">hide-if-modified-since</link></literal>
3287 <literal><link linkend="overwrite-last-modified">overwrite-last-modified</link></literal>.
3293 <term>Example usage (section):</term>
3296 <screen># Let the browser revalidate cached documents but don't
3297 # allow the server to use the revalidation headers for user tracking.
3298 {+hide-if-modified-since{-60} \
3299 +overwrite-last-modified{randomize} \
3300 +crunch-if-none-match}
3309 <!-- ~~~~~ New section ~~~~~ -->
3310 <sect3 renderas="sect4" id="crunch-incoming-cookies">
3311 <title>crunch-incoming-cookies</title>
3315 <term>Typical use:</term>
3318 Prevent the web server from setting HTTP cookies on your system
3324 <term>Effect:</term>
3327 Deletes any <quote>Set-Cookie:</quote> HTTP headers from server replies.
3334 <!-- Boolean, Parameterized, Multi-value -->
3336 <para>Boolean.</para>
3341 <term>Parameter:</term>
3353 This action is only concerned with <emphasis>incoming</emphasis> HTTP cookies. For
3354 <emphasis>outgoing</emphasis> HTTP cookies, use
3355 <literal><link linkend="crunch-outgoing-cookies">crunch-outgoing-cookies</link></literal>.
3356 Use <emphasis>both</emphasis> to disable HTTP cookies completely.
3359 It makes <emphasis>no sense at all</emphasis> to use this action in conjunction
3360 with the <literal><link linkend="session-cookies-only">session-cookies-only</link></literal> action,
3361 since it would prevent the session cookies from being set. See also
3362 <literal><link linkend="filter-content-cookies">filter-content-cookies</link></literal>.
3368 <term>Example usage:</term>
3371 <screen>+crunch-incoming-cookies</screen>
3379 <!-- ~~~~~ New section ~~~~~ -->
3380 <sect3 renderas="sect4" id="crunch-server-header">
3381 <title>crunch-server-header</title>
3387 <term>Typical use:</term>
3389 <para>Remove a server header <application>Privoxy</application> has no dedicated action for.</para>
3394 <term>Effect:</term>
3397 Deletes every header sent by the server that contains the string the user supplied as parameter.
3404 <!-- Boolean, Parameterized, Multi-value -->
3406 <para>Parameterized.</para>
3411 <term>Parameter:</term>
3423 This action allows you to block server headers for which no dedicated
3424 <application>Privoxy</application> action exists. <application>Privoxy</application>
3425 will remove every server header that contains the string you supplied as parameter.
3428 Regular expressions are <emphasis>not supported</emphasis> and you can't
3429 use this action to block different headers in the same request, unless
3430 they contain the same string.
3433 <literal>crunch-server-header</literal> is only meant for quick tests.
3434 If you have to block several different headers, or only want to modify
3435 parts of them, you should use a custom
3436 <literal><link linkend="server-header-filter">server-header filter</link></literal>.
3440 Don't block any header without understanding the consequences.
3447 <term>Example usage (section):</term>
3450 <screen># Crunch server headers that try to prevent caching
3451 { +crunch-server-header{no-cache} }
3460 <!-- ~~~~~ New section ~~~~~ -->
3461 <sect3 renderas="sect4" id="crunch-outgoing-cookies">
3462 <title>crunch-outgoing-cookies</title>
3466 <term>Typical use:</term>
3469 Prevent the web server from reading any HTTP cookies from your system
3475 <term>Effect:</term>
3478 Deletes any <quote>Cookie:</quote> HTTP headers from client requests.
3485 <!-- Boolean, Parameterized, Multi-value -->
3487 <para>Boolean.</para>
3492 <term>Parameter:</term>
3504 This action is only concerned with <emphasis>outgoing</emphasis> HTTP cookies. For
3505 <emphasis>incoming</emphasis> HTTP cookies, use
3506 <literal><link linkend="crunch-incoming-cookies">crunch-incoming-cookies</link></literal>.
3507 Use <emphasis>both</emphasis> to disable HTTP cookies completely.
3510 It makes <emphasis>no sense at all</emphasis> to use this action in conjunction
3511 with the <literal><link linkend="session-cookies-only">session-cookies-only</link></literal> action,
3512 since it would prevent the session cookies from being read.
3518 <term>Example usage:</term>
3521 <screen>+crunch-outgoing-cookies</screen>
3530 <!-- ~~~~~ New section ~~~~~ -->
3531 <sect3 renderas="sect4" id="deanimate-gifs">
3532 <title>deanimate-gifs</title>
3536 <term>Typical use:</term>
3538 <para>Stop those annoying, distracting animated GIF images.</para>
3543 <term>Effect:</term>
3546 De-animate GIF animations, i.e. reduce them to their first or last image.
3553 <!-- boolean, parameterized, Multi-value -->
3555 <para>Parameterized.</para>
3560 <term>Parameter:</term>
3563 <quote>last</quote> or <quote>first</quote>
3572 This will also shrink the images considerably (in bytes, not pixels!). If
3573 the option <quote>first</quote> is given, the first frame of the animation
3574 is used as the replacement. If <quote>last</quote> is given, the last
3575 frame of the animation is used instead, which probably makes more sense for
3576 most banner animations, but also has the risk of not showing the entire
3577 last frame (if it is only a delta to an earlier frame).
3580 You can safely use this action with patterns that will also match non-GIF
3581 objects, because no attempt will be made at anything that doesn't look like
3588 <term>Example usage:</term>
3591 <screen>+deanimate-gifs{last}</screen>
3598 <!-- ~~~~~ New section ~~~~~ -->
3599 <sect3 renderas="sect4" id="downgrade-http-version">
3600 <title>downgrade-http-version</title>
3604 <term>Typical use:</term>
3606 <para>Work around (very rare) problems with HTTP/1.1</para>
3611 <term>Effect:</term>
3614 Downgrades HTTP/1.1 client requests and server replies to HTTP/1.0.
3621 <!-- boolean, parameterized, Multi-value -->
3623 <para>Boolean.</para>
3628 <term>Parameter:</term>
3640 This is a left-over from the time when <application>Privoxy</application>
3641 didn't support important HTTP/1.1 features well. It is left here for the
3642 unlikely case that you experience HTTP/1.1 related problems with some server
3643 out there. Not all HTTP/1.1 features and requirements are supported yet,
3644 so there is a chance you might need this action.
3650 <term>Example usage (section):</term>
3653 <screen>{+downgrade-http-version}
3654 problem-host.example.com</screen>
3662 <!-- ~~~~~ New section ~~~~~ -->
3663 <sect3 renderas="sect4" id="fast-redirects">
3664 <title>fast-redirects</title>
3668 <term>Typical use:</term>
3670 <para>Fool some click-tracking scripts and speed up indirect links.</para>
3675 <term>Effect:</term>
3678 Detects redirection URLs and redirects the browser without contacting
3679 the redirection server first.
3686 <!-- boolean, parameterized, Multi-value -->
3688 <para>Parameterized.</para>
3693 <term>Parameter:</term>
3698 <quote>simple-check</quote> to just search for the string <quote>http://</quote>
3699 to detect redirection URLs.
3704 <quote>check-decoded-url</quote> to decode URLs (if necessary) before searching
3705 for redirection URLs.
3716 Many sites, like yahoo.com, don't just link to other sites. Instead, they
3717 will link to some script on their own servers, giving the destination as a
3718 parameter, which will then redirect you to the final target. URLs
3719 resulting from this scheme typically look like:
3720 <quote>http://www.example.org/click-tracker.cgi?target=http%3a//www.example.net/</quote>.
3723 Sometimes, there are even multiple consecutive redirects encoded in the
3724 URL. These redirections via scripts make your web browsing more traceable,
3725 since the server from which you follow such a link can see where you go
3726 to. Apart from that, valuable bandwidth and time is wasted, while your
3727 browser asks the server for one redirect after the other. Plus, it feeds
3731 This feature is currently not very smart and is scheduled for improvement.
3732 If it is enabled by default, you will have to create some exceptions to
3733 this action. It can lead to failures in several ways:
3736 Not every URLs with other URLs as parameters is evil.
3737 Some sites offer a real service that requires this information to work.
3738 For example a validation service needs to know, which document to validate.
3739 <literal>fast-redirects</literal> assumes that every URL parameter that
3740 looks like another URL is a redirection target, and will always redirect to
3741 the last one. Most of the time the assumption is correct, but if it isn't,
3742 the user gets redirected anyway.
3745 Another failure occurs if the URL contains other parameters after the URL parameter.
3747 <quote>http://www.example.org/?redirect=http%3a//www.example.net/&foo=bar</quote>.
3748 contains the redirection URL <quote>http://www.example.net/</quote>,
3749 followed by another parameter. <literal>fast-redirects</literal> doesn't know that
3750 and will cause a redirect to <quote>http://www.example.net/&foo=bar</quote>.
3751 Depending on the target server configuration, the parameter will be silently ignored
3752 or lead to a <quote>page not found</quote> error. You can prevent this problem by
3753 first using the <literal><link linkend="redirect">redirect</link></literal> action
3754 to remove the last part of the URL, but it requires a little effort.
3757 To detect a redirection URL, <literal>fast-redirects</literal> only
3758 looks for the string <quote>http://</quote>, either in plain text
3759 (invalid but often used) or encoded as <quote>http%3a//</quote>.
3760 Some sites use their own URL encoding scheme, encrypt the address
3761 of the target server or replace it with a database id. In theses cases
3762 <literal>fast-redirects</literal> is fooled and the request reaches the
3763 redirection server where it probably gets logged.
3769 <term>Example usage:</term>
3773 { +fast-redirects{simple-check} }
3776 { +fast-redirects{check-decoded-url} }
3777 another.example.com/testing</screen>
3786 <!-- ~~~~~ New section ~~~~~ -->
3787 <sect3 renderas="sect4" id="filter">
3788 <title>filter</title>
3792 <term>Typical use:</term>
3794 <para>Get rid of HTML and JavaScript annoyances, banner advertisements (by size),
3795 do fun text replacements, add personalized effects, etc.</para>
3800 <term>Effect:</term>
3803 All instances of text-based type, most notably HTML and JavaScript, to which
3804 this action applies, can be filtered on-the-fly through the specified regular
3805 expression based substitutions. (Note: as of version 3.0.3 plain text documents
3806 are exempted from filtering, because web servers often use the
3807 <literal>text/plain</literal> MIME type for all files whose type they don't know.)
3814 <!-- boolean, parameterized, Multi-value -->
3816 <para>Parameterized.</para>
3821 <term>Parameter:</term>
3824 The name of a content filter, as defined in the <link linkend="filter-file">filter file</link>.
3825 Filters can be defined in one or more files as defined by the
3826 <literal><link linkend="filterfile">filterfile</link></literal>
3827 option in the <link linkend="config">config file</link>.
3828 <filename>default.filter</filename> is the collection of filters
3829 supplied by the developers. Locally defined filters should go
3830 in their own file, such as <filename>user.filter</filename>.
3833 When used in its negative form,
3834 and without parameters, <emphasis>all</emphasis> filtering is completely disabled.
3843 For your convenience, there are a number of pre-defined filters available
3844 in the distribution filter file that you can use. See the examples below for
3848 Filtering requires buffering the page content, which may appear to
3849 slow down page rendering since nothing is displayed until all content has
3850 passed the filters. (It does not really take longer, but seems that way
3851 since the page is not incrementally displayed.) This effect will be more
3852 noticeable on slower connections.
3855 <quote>Rolling your own</quote>
3856 filters requires a knowledge of
3857 <ulink url="http://en.wikipedia.org/wiki/Regular_expressions"><quote>Regular
3858 Expressions</quote></ulink> and
3859 <ulink url="http://en.wikipedia.org/wiki/Html"><quote>HTML</quote></ulink>.
3860 This is very powerful feature, and potentially very intrusive.
3861 Filters should be used with caution, and where an equivalent
3862 <quote>action</quote> is not available.
3865 The amount of data that can be filtered is limited to the
3866 <literal><link linkend="buffer-limit">buffer-limit</link></literal>
3867 option in the main <link linkend="config">config file</link>. The
3868 default is 4096 KB (4 Megs). Once this limit is exceeded, the buffered
3869 data, and all pending data, is passed through unfiltered.
3872 Inappropriate MIME types, such as zipped files, are not filtered at all.
3873 (Again, only text-based types except plain text). Encrypted SSL data
3874 (from HTTPS servers) cannot be filtered either, since this would violate
3875 the integrity of the secure transaction. In some situations it might
3876 be necessary to protect certain text, like source code, from filtering
3877 by defining appropriate <literal>-filter</literal> exceptions.
3880 Compressed content can't be filtered either, unless &my-app;
3881 is compiled with zlib support (requires at least &my-app; 3.0.7),
3882 in which case &my-app; will decompress the content before filtering
3886 If you use a &my-app; version without zlib support, but want filtering to work on
3887 as much documents as possible, even those that would normally be sent compressed,
3888 you must use the <literal><link linkend="prevent-compression">prevent-compression</link></literal>
3889 action in conjunction with <literal>filter</literal>.
3892 Content filtering can achieve some of the same effects as the
3893 <literal><link linkend="block">block</link></literal>
3894 action, i.e. it can be used to block ads and banners. But the mechanism
3895 works quite differently. One effective use, is to block ad banners
3896 based on their size (see below), since many of these seem to be somewhat
3900 <link linkend="contact">Feedback</link> with suggestions for new or
3901 improved filters is particularly welcome!
3904 The below list has only the names and a one-line description of each
3905 predefined filter. There are <link linkend="predefined-filters">more
3906 verbose explanations</link> of what these filters do in the <link
3907 linkend="filter-file">filter file chapter</link>.
3913 <term>Example usage (with filters from the distribution <filename>default.filter</filename> file).
3914 See <link linkend="PREDEFINED-FILTERS">the Predefined Filters section</link> for
3915 more explanation on each:</term>
3918 <anchor id="filter-js-annoyances">
3919 <screen>+filter{js-annoyances} # Get rid of particularly annoying JavaScript abuse</screen>
3922 <anchor id="filter-js-events">
3923 <screen>+filter{js-events} # Kill all JS event bindings (Radically destructive! Only for extra nasty sites)</screen>
3926 <anchor id="filter-html-annoyances">
3927 <screen>+filter{html-annoyances} # Get rid of particularly annoying HTML abuse</screen>
3930 <anchor id="filter-content-cookies">
3931 <screen>+filter{content-cookies} # Kill cookies that come in the HTML or JS content</screen>
3934 <anchor id="filter-refresh-tags">
3935 <screen>+filter{refresh-tags} # Kill automatic refresh tags (for dial-on-demand setups)</screen>
3938 <anchor id="filter-unsolicited-popups">
3939 <screen>+filter{unsolicited-popups} # Disable only unsolicited pop-up windows. Useful if your browser lacks this ability.</screen>
3942 <anchor id="filter-all-popups">
3943 <screen>+filter{all-popups} # Kill all popups in JavaScript and HTML. Useful if your browser lacks this ability.</screen>
3946 <anchor id="filter-img-reorder">
3947 <screen>+filter{img-reorder} # Reorder attributes in <img> tags to make the banners-by-* filters more effective</screen>
3950 <anchor id="filter-banners-by-size">
3951 <screen>+filter{banners-by-size} # Kill banners by size</screen>
3954 <anchor id="filter-banners-by-link">
3955 <screen>+filter{banners-by-link} # Kill banners by their links to known clicktrackers</screen>
3958 <anchor id="filter-webbugs">
3959 <screen>+filter{webbugs} # Squish WebBugs (1x1 invisible GIFs used for user tracking)</screen>
3962 <anchor id="filter-tiny-textforms">
3963 <screen>+filter{tiny-textforms} # Extend those tiny textareas up to 40x80 and kill the hard wrap</screen>
3966 <anchor id="filter-jumping-windows">
3967 <screen>+filter{jumping-windows} # Prevent windows from resizing and moving themselves</screen>
3970 <anchor id="filter-frameset-borders">
3971 <screen>+filter{frameset-borders} # Give frames a border and make them resizeable</screen>
3974 <anchor id="filter-demoronizer">
3975 <screen>+filter{demoronizer} # Fix MS's non-standard use of standard charsets</screen>
3978 <anchor id="filter-shockwave-flash">
3979 <screen>+filter{shockwave-flash} # Kill embedded Shockwave Flash objects</screen>
3982 <anchor id="filter-quicktime-kioskmode">
3983 <screen>+filter{quicktime-kioskmode} # Make Quicktime movies savable</screen>
3986 <anchor id="filter-fun">
3987 <screen>+filter{fun} # Text replacements for subversive browsing fun!</screen>
3990 <anchor id="filter-crude-parental">
3991 <screen>+filter{crude-parental} # Crude parental filtering (demo only)</screen>
3994 <anchor id="filter-ie-exploits">
3995 <screen>+filter{ie-exploits} # Disable a known Internet Explorer bug exploits</screen>
3998 <anchor id="filter-site-specifics">
3999 <screen>+filter{site-specifics} # Custom filters for specific site related problems</screen>
4002 <anchor id="filter-google">
4003 <screen>+filter{google} # Removes text ads and other Google specific improvements</screen>
4006 <anchor id="filter-yahoo">
4007 <screen>+filter{yahoo} # Removes text ads and other Yahoo specific improvements</screen>
4010 <anchor id="filter-msn">
4011 <screen>+filter{msn} # Removes text ads and other MSN specific improvements</screen>
4014 <anchor id="filter-blogspot">
4015 <screen>+filter{blogspot} # Cleans up Blogspot blogs</screen>
4018 <anchor id="filter-no-ping">
4019 <screen>+filter{no-ping} # Removes non-standard ping attributes from anchor and area tags</screen>
4027 <!-- ~~~~~ New section ~~~~~ -->
4028 <sect3 renderas="sect4" id="force-text-mode">
4029 <title>force-text-mode</title>
4035 <term>Typical use:</term>
4037 <para>Force <application>Privoxy</application> to treat a document as if it was in some kind of <emphasis>text</emphasis> format. </para>
4042 <term>Effect:</term>
4045 Declares a document as text, even if the <quote>Content-Type:</quote> isn't detected as such.
4052 <!-- Boolean, Parameterized, Multi-value -->
4054 <para>Boolean.</para>
4059 <term>Parameter:</term>
4071 As explained <literal><link linkend="filter">above</link></literal>,
4072 <application>Privoxy</application> tries to only filter files that are
4073 in some kind of text format. The same restrictions apply to
4074 <literal><link linkend="content-type-overwrite">content-type-overwrite</link></literal>.
4075 <literal>force-text-mode</literal> declares a document as text,
4076 without looking at the <quote>Content-Type:</quote> first.
4080 Think twice before activating this action. Filtering binary data
4081 with regular expressions can cause file damage.
4088 <term>Example usage:</term>
4101 <!-- ~~~~~ New section ~~~~~ -->
4102 <sect3 renderas="sect4" id="forward-override">
4103 <title>forward-override</title>
4109 <term>Typical use:</term>
4111 <para>Change the forwarding settings based on User-Agent or request origin</para>
4116 <term>Effect:</term>
4119 Overrules the forward directives in the configuration file.
4126 <!-- Boolean, Parameterized, Multi-value -->
4128 <para>Multi-value.</para>
4133 <term>Parameter:</term>
4137 <para><quote>forward .</quote> to use a direct connection without any additional proxies.</para>
4141 <quote>forward 127.0.0.1:8123</quote> to use the HTTP proxy listening at 127.0.0.1 port 8123.
4146 <quote>forward-socks4a 127.0.0.1:9050 .</quote> to use the socks4a proxy listening at
4147 127.0.0.1 port 9050. Replace <quote>forward-socks4a</quote> with <quote>forward-socks4</quote>
4148 to use a socks4 connection (with local DNS resolution) instead, use <quote>forward-socks5</quote>
4149 for socks5 connections (with remote DNS resolution).
4154 <quote>forward-socks4a 127.0.0.1:9050 proxy.example.org:8000</quote> to use the socks4a proxy
4155 listening at 127.0.0.1 port 9050 to reach the HTTP proxy listening at proxy.example.org port 8000.
4156 Replace <quote>forward-socks4a</quote> with <quote>forward-socks4</quote> to use a socks4 connection
4157 (with local DNS resolution) instead, use <quote>forward-socks5</quote>
4158 for socks5 connections (with remote DNS resolution).
4169 This action takes parameters similar to the
4170 <link linkend="forwarding">forward</link> directives in the configuration
4171 file, but without the URL pattern. It can be used as replacement, but normally it's only
4172 used in cases where matching based on the request URL isn't sufficient.
4176 Please read the description for the <link linkend="forwarding">forward</link> directives before
4177 using this action. Forwarding to the wrong people will reduce your privacy and increase the
4178 chances of man-in-the-middle attacks.
4181 If the ports are missing or invalid, default values will be used. This might change
4182 in the future and you shouldn't rely on it. Otherwise incorrect syntax causes Privoxy
4186 Use the <ulink url="http://config.privoxy.org/show-url-info">show-url-info CGI page</ulink>
4187 to verify that your forward settings do what you thought the do.
4194 <term>Example usage:</term>
4198 # Always use direct connections for requests previously tagged as
4199 # <quote>User-Agent: fetch libfetch/2.0</quote> and make sure
4200 # resuming downloads continues to work.
4201 # This way you can continue to use Tor for your normal browsing,
4202 # without overloading the Tor network with your FreeBSD ports updates
4203 # or downloads of bigger files like ISOs.
4204 # Note that HTTP headers are easy to fake and therefore their
4205 # values are as (un)trustworthy as your clients and users.
4206 {+forward-override{forward .} \
4207 -hide-if-modified-since \
4208 -overwrite-last-modified \
4210 TAG:^User-Agent: fetch libfetch/2\.0$
4219 <!-- ~~~~~ New section ~~~~~ -->
4220 <sect3 renderas="sect4" id="handle-as-empty-document">
4221 <title>handle-as-empty-document</title>
4227 <term>Typical use:</term>
4229 <para>Mark URLs that should be replaced by empty documents <emphasis>if they get blocked</emphasis></para>
4234 <term>Effect:</term>
4237 This action alone doesn't do anything noticeable. It just marks URLs.
4238 If the <literal><link linkend="block">block</link></literal> action <emphasis>also applies</emphasis>,
4239 the presence or absence of this mark decides whether an HTML <quote>BLOCKED</quote>
4240 page, or an empty document will be sent to the client as a substitute for the blocked content.
4241 The <emphasis>empty</emphasis> document isn't literally empty, but actually contains a single space.
4248 <!-- Boolean, Parameterized, Multi-value -->
4250 <para>Boolean.</para>
4255 <term>Parameter:</term>
4267 Some browsers complain about syntax errors if JavaScript documents
4268 are blocked with <application>Privoxy's</application>
4269 default HTML page; this option can be used to silence them.
4270 And of course this action can also be used to eliminate the &my-app;
4271 BLOCKED message in frames.
4274 The content type for the empty document can be specified with
4275 <literal><link linkend="content-type-overwrite">content-type-overwrite{}</link></literal>,
4276 but usually this isn't necessary.
4282 <term>Example usage:</term>
4285 <screen># Block all documents on example.org that end with ".js",
4286 # but send an empty document instead of the usual HTML message.
4287 {+block +handle-as-empty-document}
4297 <!-- ~~~~~ New section ~~~~~ -->
4298 <sect3 renderas="sect4" id="handle-as-image">
4299 <title>handle-as-image</title>
4303 <term>Typical use:</term>
4305 <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>
4310 <term>Effect:</term>
4313 This action alone doesn't do anything noticeable. It just marks URLs as images.
4314 If the <literal><link linkend="block">block</link></literal> action <emphasis>also applies</emphasis>,
4315 the presence or absence of this mark decides whether an HTML <quote>blocked</quote>
4316 page, or a replacement image (as determined by the <literal><link
4317 linkend="set-image-blocker">set-image-blocker</link></literal> action) will be sent to the
4318 client as a substitute for the blocked content.
4325 <!-- Boolean, Parameterized, Multi-value -->
4327 <para>Boolean.</para>
4332 <term>Parameter:</term>
4344 The below generic example section is actually part of <filename>default.action</filename>.
4345 It marks all URLs with well-known image file name extensions as images and should
4349 Users will probably only want to use the handle-as-image action in conjunction with
4350 <literal><link linkend="block">block</link></literal>, to block sources of banners, whose URLs don't
4351 reflect the file type, like in the second example section.
4354 Note that you cannot treat HTML pages as images in most cases. For instance, (in-line) ad
4355 frames require an HTML page to be sent, or they won't display properly.
4356 Forcing <literal>handle-as-image</literal> in this situation will not replace the
4357 ad frame with an image, but lead to error messages.
4363 <term>Example usage (sections):</term>
4366 <screen># Generic image extensions:
4369 /.*\.(gif|jpg|jpeg|png|bmp|ico)$
4371 # These don't look like images, but they're banners and should be
4372 # blocked as images:
4374 {+block +handle-as-image}
4375 some.nasty-banner-server.com/junk.cgi\?output=trash
4377 # Banner source! Who cares if they also have non-image content?
4387 <!-- ~~~~~ New section ~~~~~ -->
4388 <sect3 renderas="sect4" id="hide-accept-language">
4389 <title>hide-accept-language</title>
4395 <term>Typical use:</term>
4397 <para>Pretend to use different language settings.</para>
4402 <term>Effect:</term>
4405 Deletes or replaces the <quote>Accept-Language:</quote> HTTP header in client requests.
4412 <!-- Boolean, Parameterized, Multi-value -->
4414 <para>Parameterized.</para>
4419 <term>Parameter:</term>
4422 Keyword: <quote>block</quote>, or any user defined value.
4431 Faking the browser's language settings can be useful to make a
4432 foreign User-Agent set with
4433 <literal><link linkend="hide-user-agent">hide-user-agent</link></literal>
4437 However some sites with content in different languages check the
4438 <quote>Accept-Language:</quote> to decide which one to take by default.
4439 Sometimes it isn't possible to later switch to another language without
4440 changing the <quote>Accept-Language:</quote> header first.
4443 Therefore it's a good idea to either only change the
4444 <quote>Accept-Language:</quote> header to languages you understand,
4445 or to languages that aren't wide spread.
4448 Before setting the <quote>Accept-Language:</quote> header
4449 to a rare language, you should consider that it helps to
4450 make your requests unique and thus easier to trace.
4451 If you don't plan to change this header frequently,
4452 you should stick to a common language.
4458 <term>Example usage (section):</term>
4461 <screen># Pretend to use Canadian language settings.
4462 {+hide-accept-language{en-ca} \
4463 +hide-user-agent{Mozilla/5.0 (X11; U; OpenBSD i386; en-CA; rv:1.8.0.4) Gecko/20060628 Firefox/1.5.0.4} \
4473 <!-- ~~~~~ New section ~~~~~ -->
4474 <sect3 renderas="sect4" id="hide-content-disposition">
4475 <title>hide-content-disposition</title>
4481 <term>Typical use:</term>
4483 <para>Prevent download menus for content you prefer to view inside the browser.</para>
4488 <term>Effect:</term>
4491 Deletes or replaces the <quote>Content-Disposition:</quote> HTTP header set by some servers.
4498 <!-- Boolean, Parameterized, Multi-value -->
4500 <para>Parameterized.</para>
4505 <term>Parameter:</term>
4508 Keyword: <quote>block</quote>, or any user defined value.
4517 Some servers set the <quote>Content-Disposition:</quote> HTTP header for
4518 documents they assume you want to save locally before viewing them.
4519 The <quote>Content-Disposition:</quote> header contains the file name
4520 the browser is supposed to use by default.
4523 In most browsers that understand this header, it makes it impossible to
4524 <emphasis>just view</emphasis> the document, without downloading it first,
4525 even if it's just a simple text file or an image.
4528 Removing the <quote>Content-Disposition:</quote> header helps
4529 to prevent this annoyance, but some browsers additionally check the
4530 <quote>Content-Type:</quote> header, before they decide if they can
4531 display a document without saving it first. In these cases, you have
4532 to change this header as well, before the browser stops displaying
4536 It is also possible to change the server's file name suggestion
4537 to another one, but in most cases it isn't worth the time to set
4541 This action will probably be removed in the future,
4542 use server-header filters instead.
4548 <term>Example usage:</term>
4551 <screen># Disarm the download link in Sourceforge's patch tracker
4553 +content-type-overwrite{text/plain}\
4554 +hide-content-disposition{block} }
4555 .sourceforge.net/tracker/download\.php</screen>
4563 <!-- ~~~~~ New section ~~~~~ -->
4564 <sect3 renderas="sect4" id="hide-if-modified-since">
4565 <title>hide-if-modified-since</title>
4571 <term>Typical use:</term>
4573 <para>Prevent yet another way to track the user's steps between sessions.</para>
4578 <term>Effect:</term>
4581 Deletes the <quote>If-Modified-Since:</quote> HTTP client header or modifies its value.
4588 <!-- Boolean, Parameterized, Multi-value -->
4590 <para>Parameterized.</para>
4595 <term>Parameter:</term>
4598 Keyword: <quote>block</quote>, or a user defined value that specifies a range of hours.
4607 Removing this header is useful for filter testing, where you want to force a real
4608 reload instead of getting status code <quote>304</quote>, which would cause the
4609 browser to use a cached copy of the page.
4612 Instead of removing the header, <literal>hide-if-modified-since</literal> can
4613 also add or subtract a random amount of time to/from the header's value.
4614 You specify a range of minutes where the random factor should be chosen from and
4615 <application>Privoxy</application> does the rest. A negative value means
4616 subtracting, a positive value adding.
4619 Randomizing the value of the <quote>If-Modified-Since:</quote> makes
4620 it less likely that the server can use the time as a cookie replacement,
4621 but you will run into caching problems if the random range is too high.
4624 It is a good idea to only use a small negative value and let
4625 <literal><link linkend="overwrite-last-modified">overwrite-last-modified</link></literal>
4626 handle the greater changes.
4629 It is also recommended to use this action together with
4630 <literal><link linkend="crunch-if-none-match">crunch-if-none-match</link></literal>,
4631 otherwise it's more or less pointless.
4637 <term>Example usage (section):</term>
4640 <screen># Let the browser revalidate but make tracking based on the time less likely.
4641 {+hide-if-modified-since{-60} \
4642 +overwrite-last-modified{randomize} \
4643 +crunch-if-none-match}
4652 <!-- ~~~~~ New section ~~~~~ -->
4653 <sect3 renderas="sect4" id="hide-forwarded-for-headers">
4654 <title>hide-forwarded-for-headers</title>
4657 <term>Typical use:</term>
4659 <para>Improve privacy by not forwarding the source of the request in the HTTP headers.</para>
4664 <term>Effect:</term>
4667 Deletes any existing <quote>X-Forwarded-for:</quote> HTTP header from client requests.
4674 <!-- Boolean, Parameterized, Multi-value -->
4676 <para>Boolean.</para>
4681 <term>Parameter:</term>
4693 It is safe and recommended to leave this on.
4699 <term>Example usage:</term>
4702 <screen>+hide-forwarded-for-headers</screen>
4710 <!-- ~~~~~ New section ~~~~~ -->
4711 <sect3 renderas="sect4" id="hide-from-header">
4712 <title>hide-from-header</title>
4716 <term>Typical use:</term>
4718 <para>Keep your (old and ill) browser from telling web servers your email address</para>
4723 <term>Effect:</term>
4726 Deletes any existing <quote>From:</quote> HTTP header, or replaces it with the
4734 <!-- Boolean, Parameterized, Multi-value -->
4736 <para>Parameterized.</para>
4741 <term>Parameter:</term>
4744 Keyword: <quote>block</quote>, or any user defined value.
4753 The keyword <quote>block</quote> will completely remove the header
4754 (not to be confused with the <literal><link linkend="block">block</link></literal>
4758 Alternately, you can specify any value you prefer to be sent to the web
4759 server. If you do, it is a matter of fairness not to use any address that
4760 is actually used by a real person.
4763 This action is rarely needed, as modern web browsers don't send
4764 <quote>From:</quote> headers anymore.
4770 <term>Example usage:</term>
4773 <screen>+hide-from-header{block}</screen> or
4774 <screen>+hide-from-header{spam-me-senseless@sittingduck.example.com}</screen>
4782 <!-- ~~~~~ New section ~~~~~ -->
4783 <sect3 renderas="sect4" id="hide-referrer">
4784 <title>hide-referrer</title>
4785 <anchor id="hide-referer">
4788 <term>Typical use:</term>
4790 <para>Conceal which link you followed to get to a particular site</para>
4795 <term>Effect:</term>
4798 Deletes the <quote>Referer:</quote> (sic) HTTP header from the client request,
4799 or replaces it with a forged one.
4806 <!-- Boolean, Parameterized, Multi-value -->
4808 <para>Parameterized.</para>
4813 <term>Parameter:</term>
4817 <para><quote>conditional-block</quote> to delete the header completely if the host has changed.</para>
4820 <para><quote>conditional-forge</quote> to forge the header if the host has changed.</para>
4823 <para><quote>block</quote> to delete the header unconditionally.</para>
4826 <para><quote>forge</quote> to pretend to be coming from the homepage of the server we are talking to.</para>
4829 <para>Any other string to set a user defined referrer.</para>
4839 <literal>conditional-block</literal> is the only parameter,
4840 that isn't easily detected in the server's log file. If it blocks the
4841 referrer, the request will look like the visitor used a bookmark or
4842 typed in the address directly.
4845 Leaving the referrer unmodified for requests on the same host
4846 allows the server owner to see the visitor's <quote>click path</quote>,
4847 but in most cases she could also get that information by comparing
4848 other parts of the log file: for example the User-Agent if it isn't
4849 a very common one, or the user's IP address if it doesn't change between
4853 Always blocking the referrer, or using a custom one, can lead to
4854 failures on servers that check the referrer before they answer any
4855 requests, in an attempt to prevent their content from being
4856 embedded or linked to elsewhere.
4859 Both <literal>conditional-block</literal> and <literal>forge</literal>
4860 will work with referrer checks, as long as content and valid referring page
4861 are on the same host. Most of the time that's the case.
4864 <literal>hide-referer</literal> is an alternate spelling of
4865 <literal>hide-referrer</literal> and the two can be can be freely
4866 substituted with each other. (<quote>referrer</quote> is the
4867 correct English spelling, however the HTTP specification has a bug - it
4868 requires it to be spelled as <quote>referer</quote>.)
4874 <term>Example usage:</term>
4877 <screen>+hide-referrer{forge}</screen> or
4878 <screen>+hide-referrer{http://www.yahoo.com/}</screen>
4886 <!-- ~~~~~ New section ~~~~~ -->
4887 <sect3 renderas="sect4" id="hide-user-agent">
4888 <title>hide-user-agent</title>
4892 <term>Typical use:</term>
4894 <para>Try to conceal your type of browser and client operating system</para>
4899 <term>Effect:</term>
4902 Replaces the value of the <quote>User-Agent:</quote> HTTP header
4903 in client requests with the specified value.
4910 <!-- Boolean, Parameterized, Multi-value -->
4912 <para>Parameterized.</para>
4917 <term>Parameter:</term>
4920 Any user-defined string.
4930 This can lead to problems on web sites that depend on looking at this header in
4931 order to customize their content for different browsers (which, by the
4932 way, is <emphasis>NOT</emphasis> the right thing to do: good web sites
4933 work browser-independently).
4937 Using this action in multi-user setups or wherever different types of
4938 browsers will access the same <application>Privoxy</application> is
4939 <emphasis>not recommended</emphasis>. In single-user, single-browser
4940 setups, you might use it to delete your OS version information from
4941 the headers, because it is an invitation to exploit known bugs for your
4942 OS. It is also occasionally useful to forge this in order to access
4943 sites that won't let you in otherwise (though there may be a good
4944 reason in some cases). Example of this: some MSN sites will not
4945 let <application>Mozilla</application> enter, yet forging to a
4946 <application>Netscape 6.1</application> user-agent works just fine.
4947 (Must be just a silly MS goof, I'm sure :-).
4950 More information on known user-agent strings can be found at
4951 <ulink url="http://www.user-agents.org/">http://www.user-agents.org/</ulink>
4953 <ulink url="http://en.wikipedia.org/wiki/User_agent">http://en.wikipedia.org/wiki/User_agent</ulink>.
4959 <term>Example usage:</term>
4962 <screen>+hide-user-agent{Netscape 6.1 (X11; I; Linux 2.4.18 i686)}</screen>
4970 <!-- ~~~~~ New section ~~~~~ -->
4971 <sect3 renderas="sect4" id="inspect-jpegs">
4972 <title>inspect-jpegs</title>
4975 <term>Typical use:</term>
4977 <para>Try to protect against a MS buffer over-run in JPEG processing</para>
4982 <term>Effect:</term>
4985 Protect against a known exploit
4992 <!-- Boolean, Parameterized, Multi-value -->
4994 <para>Boolean.</para>
4999 <term>Parameter:</term>
5011 See Microsoft Security Bulletin MS04-028. JPEG images are one of the most
5012 common image types found across the Internet. The exploit as described can
5013 allow execution of code on the target system, giving an attacker access
5014 to the system in question by merely planting an altered JPEG image, which
5015 would have no obvious indications of what lurks inside. This action
5016 tries to prevent this exploit if delivered through unencrypted HTTP.
5019 Note that the exploit mentioned is several years old
5020 and it's unlikely that your client is still vulnerable
5021 against it. This action may be removed in one of the
5029 <term>Example usage:</term>
5031 <para><screen>+inspect-jpegs</screen></para>
5038 <!-- ~~~~~ New section ~~~~~ -->
5039 <sect3 renderas="sect4" id="kill-popups">
5040 <title>kill-popups<anchor id="kill-popup"></title>
5044 <term>Typical use:</term>
5046 <para>Eliminate those annoying pop-up windows (deprecated)</para>
5051 <term>Effect:</term>
5054 While loading the document, replace JavaScript code that opens
5055 pop-up windows with (syntactically neutral) dummy code on the fly.
5062 <!-- Boolean, Parameterized, Multi-value -->
5064 <para>Boolean.</para>
5069 <term>Parameter:</term>
5081 This action is basically a built-in, hardwired special-purpose filter
5082 action, but there are important differences: For <literal>kill-popups</literal>,
5083 the document need not be buffered, so it can be incrementally rendered while
5084 downloading. But <literal>kill-popups</literal> doesn't catch as many pop-ups as
5086 linkend="FILTER-ALL-POPUPS">filter{<replaceable>all-popups</replaceable>}</link></literal>
5087 does and is not as smart as <literal><link
5088 linkend="FILTER-UNSOLICITED-POPUPS">filter{<replaceable>unsolicited-popups</replaceable>}</link>
5092 Think of it as a fast and efficient replacement for a filter that you
5093 can use if you don't want any filtering at all. Note that it doesn't make
5094 sense to combine it with any <literal><link linkend="filter">filter</link></literal> action,
5095 since as soon as one <literal><link linkend="filter">filter</link></literal> applies,
5096 the whole document needs to be buffered anyway, which destroys the advantage of
5097 the <literal>kill-popups</literal> action over its filter equivalent.
5100 Killing all pop-ups unconditionally is problematic. Many shops and banks rely on
5101 pop-ups to display forms, shopping carts etc, and the <literal><link
5102 linkend="FILTER-UNSOLICITED-POPUPS">filter{<replaceable>unsolicited-popups</replaceable>}</link>
5103 </literal> does a better job of catching only the unwanted ones.
5106 If the only kind of pop-ups that you want to kill are exit consoles (those
5107 <emphasis>really nasty</emphasis> windows that appear when you close an other
5108 one), you might want to use
5110 linkend="filter">filter</link>{<replaceable>js-annoyances</replaceable>}</literal>
5114 This action is most appropriate for browsers that don't have any controls
5115 for unwanted pop-ups. Not recommended for general usage.
5118 This action doesn't work very reliable and may be removed in future releases.
5124 <term>Example usage:</term>
5126 <para><screen>+kill-popups</screen></para>
5133 <!-- ~~~~~ New section ~~~~~ -->
5134 <sect3 renderas="sect4" id="limit-connect">
5135 <title>limit-connect</title>
5139 <term>Typical use:</term>
5141 <para>Prevent abuse of <application>Privoxy</application> as a TCP proxy relay or disable SSL for untrusted sites</para>
5146 <term>Effect:</term>
5149 Specifies to which ports HTTP CONNECT requests are allowable.
5156 <!-- Boolean, Parameterized, Multi-value -->
5158 <para>Parameterized.</para>
5163 <term>Parameter:</term>
5166 A comma-separated list of ports or port ranges (the latter using dashes, with the minimum
5167 defaulting to 0 and the maximum to 65K).
5176 By default, i.e. if no <literal>limit-connect</literal> action applies,
5177 <application>Privoxy</application> only allows HTTP CONNECT
5178 requests to port 443 (the standard, secure HTTPS port). Use
5179 <literal>limit-connect</literal> if more fine-grained control is desired
5180 for some or all destinations.
5183 The CONNECT methods exists in HTTP to allow access to secure websites
5184 (<quote>https://</quote> URLs) through proxies. It works very simply:
5185 the proxy connects to the server on the specified port, and then
5186 short-circuits its connections to the client and to the remote server.
5187 This means CONNECT-enabled proxies can be used as TCP relays very easily.
5190 <application>Privoxy</application> relays HTTPS traffic without seeing
5191 the decoded content. Websites can leverage this limitation to circumvent &my-app;'s
5192 filters. By specifying an invalid port range you can disable HTTPS entirely.
5193 If you plan to disable SSL by default, consider enabling
5194 <literal><link linkend="treat-forbidden-connects-like-blocks ">treat-forbidden-connects-like-blocks</link></literal>
5195 as well, to be able to quickly create exceptions.
5201 <term>Example usages:</term>
5203 <!-- I had trouble getting the spacing to look right in my browser -->
5204 <!-- I probably have the wrong font setup, bollocks. -->
5205 <!-- Apparently the emphasis tag uses a proportional font no matter what -->
5207 <screen>+limit-connect{443} # This is the default and need not be specified.
5208 +limit-connect{80,443} # Ports 80 and 443 are OK.
5209 +limit-connect{-3, 7, 20-100, 500-} # Ports less than 3, 7, 20 to 100 and above 500 are OK.
5210 +limit-connect{-} # All ports are OK
5211 +limit-connect{,} # No HTTPS/SSL traffic is allowed</screen>
5218 <!-- ~~~~~ New section ~~~~~ -->
5219 <sect3 renderas="sect4" id="prevent-compression">
5220 <title>prevent-compression</title>
5224 <term>Typical use:</term>
5227 Ensure that servers send the content uncompressed, so it can be
5228 passed through <literal><link linkend="filter">filter</link></literal>s.
5234 <term>Effect:</term>
5237 Removes the Accept-Encoding header which can be used to ask for compressed transfer.
5244 <!-- Boolean, Parameterized, Multi-value -->
5246 <para>Boolean.</para>
5251 <term>Parameter:</term>
5263 More and more websites send their content compressed by default, which
5264 is generally a good idea and saves bandwidth. But the <literal><link
5265 linkend="filter">filter</link></literal>, <literal><link linkend="deanimate-gifs">deanimate-gifs</link></literal>
5266 and <literal><link linkend="kill-popups">kill-popups</link></literal> actions need
5267 access to the uncompressed data.
5270 When compiled with zlib support (available since &my-app; 3.0.7), content that should be
5271 filtered is decompressed on-the-fly and you don't have to worry about this action.
5272 If you are using an older &my-app; version, or one that hasn't been compiled with zlib
5273 support, this action can be used to convince the server to send the content uncompressed.
5276 Most text-based instances compress very well, the size is seldom decreased by less than 50%,
5277 for markup-heavy instances like news feeds saving more than 90% of the original size isn't
5281 Not using compression will therefore slow down the transfer, and you should only
5282 enable this action if you really need it. As of &my-app; 3.0.7 it's disabled in all
5283 predefined action settings.
5286 Note that some (rare) ill-configured sites don't handle requests for uncompressed
5287 documents correctly. Broken PHP applications tend to send an empty document body,
5288 some IIS versions only send the beginning of the content. If you enable
5289 <literal>prevent-compression</literal> per default, you might want to add
5290 exceptions for those sites. See the example for how to do that.
5296 <term>Example usage (sections):</term>
5300 # Selectively turn off compression, and enable a filter
5302 { +filter{tiny-textforms} +prevent-compression }
5303 # Match only these sites
5308 # Or instead, we could set a universal default:
5310 { +prevent-compression }
5313 # Then maybe make exceptions for broken sites:
5315 { -prevent-compression }
5316 .compusa.com/</screen>
5325 <!-- ~~~~~ New section ~~~~~ -->
5326 <sect3 renderas="sect4" id="overwrite-last-modified">
5327 <title>overwrite-last-modified</title>
5333 <term>Typical use:</term>
5335 <para>Prevent yet another way to track the user's steps between sessions.</para>
5340 <term>Effect:</term>
5343 Deletes the <quote>Last-Modified:</quote> HTTP server header or modifies its value.
5350 <!-- Boolean, Parameterized, Multi-value -->
5352 <para>Parameterized.</para>
5357 <term>Parameter:</term>
5360 One of the keywords: <quote>block</quote>, <quote>reset-to-request-time</quote>
5361 and <quote>randomize</quote>
5370 Removing the <quote>Last-Modified:</quote> header is useful for filter
5371 testing, where you want to force a real reload instead of getting status
5372 code <quote>304</quote>, which would cause the browser to reuse the old
5373 version of the page.
5376 The <quote>randomize</quote> option overwrites the value of the
5377 <quote>Last-Modified:</quote> header with a randomly chosen time
5378 between the original value and the current time. In theory the server
5379 could send each document with a different <quote>Last-Modified:</quote>
5380 header to track visits without using cookies. <quote>Randomize</quote>
5381 makes it impossible and the browser can still revalidate cached documents.
5384 <quote>reset-to-request-time</quote> overwrites the value of the
5385 <quote>Last-Modified:</quote> header with the current time. You could use
5386 this option together with
5387 <literal><link linkend="hide-if-modified-since">hided-if-modified-since</link></literal>
5388 to further customize your random range.
5391 The preferred parameter here is <quote>randomize</quote>. It is safe
5392 to use, as long as the time settings are more or less correct.
5393 If the server sets the <quote>Last-Modified:</quote> header to the time
5394 of the request, the random range becomes zero and the value stays the same.
5395 Therefore you should later randomize it a second time with
5396 <literal><link linkend="hide-if-modified-since">hided-if-modified-since</link></literal>,
5400 It is also recommended to use this action together with
5401 <literal><link linkend="crunch-if-none-match">crunch-if-none-match</link></literal>.
5407 <term>Example usage:</term>
5410 <screen># Let the browser revalidate without being tracked across sessions
5411 { +hide-if-modified-since{-60} \
5412 +overwrite-last-modified{randomize} \
5413 +crunch-if-none-match}
5422 <!-- ~~~~~ New section ~~~~~ -->
5423 <sect3 renderas="sect4" id="redirect">
5424 <title>redirect</title>
5430 <term>Typical use:</term>
5433 Redirect requests to other sites.
5439 <term>Effect:</term>
5442 Convinces the browser that the requested document has been moved
5443 to another location and the browser should get it from there.
5450 <!-- Boolean, Parameterized, Multi-value -->
5452 <para>Parameterized</para>
5457 <term>Parameter:</term>
5460 An absolute URL or a single pcrs command.
5469 Requests to which this action applies are answered with a
5470 HTTP redirect to URLs of your choosing. The new URL is
5471 either provided as parameter, or derived by applying a
5472 single pcrs command to the original URL.
5475 This action will be ignored if you use it together with
5476 <literal><link linkend="block">block</link></literal>.
5477 It can be combined with
5478 <literal><link linkend="fast-redirects">fast-redirects{check-decoded-url}</link></literal>
5479 to redirect to a decoded version of a rewritten URL.
5482 Use this action carefully, make sure not to create redirection loops
5483 and be aware that using your own redirects might make it
5484 possible to fingerprint your requests.
5490 <term>Example usages:</term>
5493 <screen># Replace example.com's style sheet with another one
5494 { +redirect{http://localhost/css-replacements/example.com.css} }
5495 example.com/stylesheet\.css
5497 # Create a short, easy to remember nickname for a favorite site
5498 # (relies on the browser accept and forward invalid URLs to &my-app;)
5499 { +redirect{http://www.privoxy.org/user-manual/actions-file.html} }
5502 # Always use the expanded view for Undeadly.org articles
5503 # (Note the $ at the end of the URL pattern to make sure
5504 # the request for the rewritten URL isn't redirected as well)
5505 {+redirect{s@$@&mode=expanded@}}
5506 undeadly.org/cgi\?action=article&sid=\d*$</screen>
5515 <!-- ~~~~~ New section ~~~~~ -->
5516 <sect3 renderas="sect4" id="send-vanilla-wafer">
5517 <title>send-vanilla-wafer</title>
5521 <term>Typical use:</term>
5524 Feed log analysis scripts with useless data.
5530 <term>Effect:</term>
5533 Sends a cookie with each request stating that you do not accept any copyright
5534 on cookies sent to you, and asking the site operator not to track you.
5541 <!-- Boolean, Parameterized, Multi-value -->
5543 <para>Boolean.</para>
5548 <term>Parameter:</term>
5560 The vanilla wafer is a (relatively) unique header and could conceivably be used to track you.
5563 This action is rarely used and not enabled in the default configuration.
5569 <term>Example usage:</term>
5572 <screen>+send-vanilla-wafer</screen>
5581 <!-- ~~~~~ New section ~~~~~ -->
5582 <sect3 renderas="sect4" id="send-wafer">
5583 <title>send-wafer</title>
5587 <term>Typical use:</term>
5590 Send custom cookies or feed log analysis scripts with even more useless data.
5596 <term>Effect:</term>
5599 Sends a custom, user-defined cookie with each request.
5606 <!-- Boolean, Parameterized, Multi-value -->
5608 <para>Multi-value.</para>
5613 <term>Parameter:</term>
5616 A string of the form <quote><replaceable class="option">name</replaceable>=<replaceable
5617 class="parameter">value</replaceable></quote>.
5626 Being multi-valued, multiple instances of this action can apply to the same request,
5627 resulting in multiple cookies being sent.
5630 This action is rarely used and not enabled in the default configuration.
5635 <term>Example usage (section):</term>
5638 <screen>{+send-wafer{UsingPrivoxy=true}}
5639 my-internal-testing-server.void</screen>
5647 <!-- ~~~~~ New section ~~~~~ -->
5648 <sect3 renderas="sect4" id="server-header-filter">
5649 <title>server-header-filter</title>
5653 <term>Typical use:</term>
5656 Rewrite or remove single server headers.
5662 <term>Effect:</term>
5665 All server headers to which this action applies are filtered on-the-fly
5666 through the specified regular expression based substitutions.
5673 <!-- boolean, parameterized, Multi-value -->
5675 <para>Parameterized.</para>
5680 <term>Parameter:</term>
5683 The name of a server-header filter, as defined in one of the
5684 <link linkend="filter-file">filter files</link>.
5693 Server-header filters are applied to each header on its own, not to
5694 all at once. This makes it easier to diagnose problems, but on the downside
5695 you can't write filters that only change header x if header y's value is z.
5696 You can do that by using tags though.
5699 Server-header filters are executed after the other header actions have finished
5700 and use their output as input.
5703 Please refer to the <link linkend="filter-file">filter file chapter</link>
5704 to learn which server-header filters are available by default, and how to
5711 <term>Example usage (section):</term>
5715 {+server-header-filter{html-to-xml}}
5716 example.org/xml-instance-that-is-delivered-as-html
5718 {+server-header-filter{xml-to-html}}
5719 example.org/instance-that-is-delivered-as-xml-but-is-not
5729 <!-- ~~~~~ New section ~~~~~ -->
5730 <sect3 renderas="sect4" id="server-header-tagger">
5731 <title>server-header-tagger</title>
5735 <term>Typical use:</term>
5738 Enable or disable filters based on the Content-Type header.
5744 <term>Effect:</term>
5747 Server headers to which this action applies are filtered on-the-fly through
5748 the specified regular expression based substitutions, the result is used as
5756 <!-- boolean, parameterized, Multi-value -->
5758 <para>Parameterized.</para>
5763 <term>Parameter:</term>
5766 The name of a server-header tagger, as defined in one of the
5767 <link linkend="filter-file">filter files</link>.
5776 Server-header taggers are applied to each header on its own,
5777 and as the header isn't modified, each tagger <quote>sees</quote>
5781 Server-header taggers are executed before all other header actions
5782 that modify server headers. Their tags can be used to control
5783 all of the other server-header actions, the content filters
5784 and the crunch actions (<link linkend="redirect">redirect</link>
5785 and <link linkend="block">block</link>).
5788 Obviously crunching based on tags created by server-header taggers
5789 doesn't prevent the request from showing up in the server's log file.
5796 <term>Example usage (section):</term>
5800 # Tag every request with the content type declared by the server
5801 {+server-header-tagger{content-type}}
5812 <!-- ~~~~~ New section ~~~~~ -->
5813 <sect3 renderas="sect4" id="session-cookies-only">
5814 <title>session-cookies-only</title>
5818 <term>Typical use:</term>
5821 Allow only temporary <quote>session</quote> cookies (for the current
5822 browser session <emphasis>only</emphasis>).
5828 <term>Effect:</term>
5831 Deletes the <quote>expires</quote> field from <quote>Set-Cookie:</quote>
5832 server headers. Most browsers will not store such cookies permanently and
5833 forget them in between sessions.
5840 <!-- Boolean, Parameterized, Multi-value -->
5842 <para>Boolean.</para>
5847 <term>Parameter:</term>
5859 This is less strict than <literal><link linkend="crunch-incoming-cookies">crunch-incoming-cookies</link></literal> /
5860 <literal><link linkend="crunch-outgoing-cookies">crunch-outgoing-cookies</link></literal> and allows you to browse
5861 websites that insist or rely on setting cookies, without compromising your privacy too badly.
5864 Most browsers will not permanently store cookies that have been processed by
5865 <literal>session-cookies-only</literal> and will forget about them between sessions.
5866 This makes profiling cookies useless, but won't break sites which require cookies so
5867 that you can log in for transactions. This is generally turned on for all
5868 sites, and is the recommended setting.
5871 It makes <emphasis>no sense at all</emphasis> to use <literal>session-cookies-only</literal>
5872 together with <literal><link linkend="crunch-incoming-cookies">crunch-incoming-cookies</link></literal> or
5873 <literal><link linkend="crunch-outgoing-cookies">crunch-outgoing-cookies</link></literal>. If you do, cookies
5874 will be plainly killed.
5877 Note that it is up to the browser how it handles such cookies without an <quote>expires</quote>
5878 field. If you use an exotic browser, you might want to try it out to be sure.
5881 This setting also has no effect on cookies that may have been stored
5882 previously by the browser before starting <application>Privoxy</application>.
5883 These would have to be removed manually.
5886 <application>Privoxy</application> also uses
5887 the <link linkend="filter-content-cookies">content-cookies filter</link>
5888 to block some types of cookies. Content cookies are not effected by
5889 <literal>session-cookies-only</literal>.
5895 <term>Example usage:</term>
5898 <screen>+session-cookies-only</screen>
5906 <!-- ~~~~~ New section ~~~~~ -->
5907 <sect3 renderas="sect4" id="set-image-blocker">
5908 <title>set-image-blocker</title>
5912 <term>Typical use:</term>
5914 <para>Choose the replacement for blocked images</para>
5919 <term>Effect:</term>
5922 This action alone doesn't do anything noticeable. If <emphasis>both</emphasis>
5923 <literal><link linkend="block">block</link></literal> <emphasis>and</emphasis> <literal><link
5924 linkend="handle-as-image">handle-as-image</link></literal> <emphasis>also</emphasis>
5925 apply, i.e. if the request is to be blocked as an image,
5926 <emphasis>then</emphasis> the parameter of this action decides what will be
5927 sent as a replacement.
5934 <!-- Boolean, Parameterized, Multi-value -->
5936 <para>Parameterized.</para>
5941 <term>Parameter:</term>
5946 <quote>pattern</quote> to send a built-in checkerboard pattern image. The image is visually
5947 decent, scales very well, and makes it obvious where banners were busted.
5952 <quote>blank</quote> to send a built-in transparent image. This makes banners disappear
5953 completely, but makes it hard to detect where <application>Privoxy</application> has blocked
5954 images on a given page and complicates troubleshooting if <application>Privoxy</application>
5955 has blocked innocent images, like navigation icons.
5960 <quote><replaceable class="parameter">target-url</replaceable></quote> to
5961 send a redirect to <replaceable class="parameter">target-url</replaceable>. You can redirect
5962 to any image anywhere, even in your local filesystem via <quote>file:///</quote> URL.
5963 (But note that not all browsers support redirecting to a local file system).
5966 A good application of redirects is to use special <application>Privoxy</application>-built-in
5967 URLs, which send the built-in images, as <replaceable class="parameter">target-url</replaceable>.
5968 This has the same visual effect as specifying <quote>blank</quote> or <quote>pattern</quote> in
5969 the first place, but enables your browser to cache the replacement image, instead of requesting
5970 it over and over again.
5981 The URLs for the built-in images are <quote>http://config.privoxy.org/send-banner?type=<replaceable
5982 class="parameter">type</replaceable></quote>, where <replaceable class="parameter">type</replaceable> is
5983 either <quote>blank</quote> or <quote>pattern</quote>.
5986 There is a third (advanced) type, called <quote>auto</quote>. It is <emphasis>NOT</emphasis> to be
5987 used in <literal>set-image-blocker</literal>, but meant for use from <link linkend="filter-file">filters</link>.
5988 Auto will select the type of image that would have applied to the referring page, had it been an image.
5994 <term>Example usage:</term>
6000 <screen>+set-image-blocker{pattern}</screen>
6003 Redirect to the BSD daemon:
6006 <screen>+set-image-blocker{http://www.freebsd.org/gifs/dae_up3.gif}</screen>
6009 Redirect to the built-in pattern for better caching:
6012 <screen>+set-image-blocker{http://config.privoxy.org/send-banner?type=pattern}</screen>
6020 <!-- ~~~~~ New section ~~~~~ -->
6021 <sect3 renderas="sect4" id="treat-forbidden-connects-like-blocks">
6022 <title>treat-forbidden-connects-like-blocks</title>
6028 <term>Typical use:</term>
6030 <para>Block forbidden connects with an easy to find error message.</para>
6035 <term>Effect:</term>
6038 If this action is enabled, <application>Privoxy</application> no longer
6039 makes a difference between forbidden connects and ordinary blocks.
6046 <!-- Boolean, Parameterized, Multi-value -->
6048 <para>Boolean</para>
6053 <term>Parameter:</term>
6063 By default <application>Privoxy</application> answers
6064 <link linkend="limit-connect">forbidden <quote>Connect</quote> requests</link>
6065 with a short error message inside the headers. If the browser doesn't display
6066 headers (most don't), you just see an empty page.
6069 With this action enabled, <application>Privoxy</application> displays
6070 the message that is used for ordinary blocks instead. If you decide
6071 to make an exception for the page in question, you can do so by
6072 following the <quote>See why</quote> link.
6075 For <quote>Connect</quote> requests the clients tell
6076 <application>Privoxy</application> which host they are interested
6077 in, but not which document they plan to get later. As a result, the
6078 <quote>Go there anyway</quote> wouldn't work and is therefore suppressed.
6084 <term>Example usage:</term>
6087 <screen>+treat-forbidden-connects-like-blocks</screen>
6095 <!-- ~~~~~ New section ~~~~~ -->
6097 <title>Summary</title>
6099 Note that many of these actions have the potential to cause a page to
6100 misbehave, possibly even not to display at all. There are many ways
6101 a site designer may choose to design his site, and what HTTP header
6102 content, and other criteria, he may depend on. There is no way to have hard
6103 and fast rules for all sites. See the <link
6104 linkend="ACTIONSANAT">Appendix</link> for a brief example on troubleshooting
6110 <!-- ~~~~~ New section ~~~~~ -->
6111 <sect2 id="aliases">
6112 <title>Aliases</title>
6114 Custom <quote>actions</quote>, known to <application>Privoxy</application>
6115 as <quote>aliases</quote>, can be defined by combining other actions.
6116 These can in turn be invoked just like the built-in actions.
6117 Currently, an alias name can contain any character except space, tab,
6119 <quote>{</quote> and <quote>}</quote>, but we <emphasis>strongly
6120 recommend</emphasis> that you only use <quote>a</quote> to <quote>z</quote>,
6121 <quote>0</quote> to <quote>9</quote>, <quote>+</quote>, and <quote>-</quote>.
6122 Alias names are not case sensitive, and are not required to start with a
6123 <quote>+</quote> or <quote>-</quote> sign, since they are merely textually
6127 Aliases can be used throughout the actions file, but they <emphasis>must be
6128 defined in a special section at the top of the file!</emphasis>
6129 And there can only be one such section per actions file. Each actions file may
6130 have its own alias section, and the aliases defined in it are only visible
6134 There are two main reasons to use aliases: One is to save typing for frequently
6135 used combinations of actions, the other one is a gain in flexibility: If you
6136 decide once how you want to handle shops by defining an alias called
6137 <quote>shop</quote>, you can later change your policy on shops in
6138 <emphasis>one</emphasis> place, and your changes will take effect everywhere
6139 in the actions file where the <quote>shop</quote> alias is used. Calling aliases
6140 by their purpose also makes your actions files more readable.
6143 Currently, there is one big drawback to using aliases, though:
6144 <application>Privoxy</application>'s built-in web-based action file
6145 editor honors aliases when reading the actions files, but it expands
6146 them before writing. So the effects of your aliases are of course preserved,
6147 but the aliases themselves are lost when you edit sections that use aliases
6152 Now let's define some aliases...
6157 # Useful custom aliases we can use later.
6159 # Note the (required!) section header line and that this section
6160 # must be at the top of the actions file!
6164 # These aliases just save typing later:
6165 # (Note that some already use other aliases!)
6167 +crunch-all-cookies = +<link linkend="CRUNCH-INCOMING-COOKIES">crunch-incoming-cookies</link> +<link linkend="CRUNCH-OUTGOING-COOKIES">crunch-outgoing-cookies</link>
6168 -crunch-all-cookies = -<link linkend="CRUNCH-INCOMING-COOKIES">crunch-incoming-cookies</link> -<link linkend="CRUNCH-OUTGOING-COOKIES">crunch-outgoing-cookies</link>
6169 +block-as-image = +block +handle-as-image
6170 allow-all-cookies = -crunch-all-cookies -<link linkend="SESSION-COOKIES-ONLY">session-cookies-only</link> -<link linkend="FILTER-CONTENT-COOKIES">filter{content-cookies}</link>
6172 # These aliases define combinations of actions
6173 # that are useful for certain types of sites:
6175 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>
6177 shop = -crunch-all-cookies -<link linkend="FILTER-ALL-POPUPS">filter{all-popups}</link> -<link linkend="KILL-POPUPS">kill-popups</link>
6179 # Short names for other aliases, for really lazy people ;-)
6181 c0 = +crunch-all-cookies
6182 c1 = -crunch-all-cookies</screen>
6186 ...and put them to use. These sections would appear in the lower part of an
6187 actions file and define exceptions to the default actions (as specified further
6188 up for the <quote>/</quote> pattern):
6193 # These sites are either very complex or very keen on
6194 # user data and require minimal interference to work:
6197 .office.microsoft.com
6198 .windowsupdate.microsoft.com
6199 # Gmail is really mail.google.com, not gmail.com
6203 # Allow cookies (for setting and retrieving your customer data)
6207 .worldpay.com # for quietpc.com
6210 # These shops require pop-ups:
6212 {-kill-popups -filter{all-popups} -filter{unsolicited-popups}}
6214 .overclockers.co.uk</screen>
6218 Aliases like <quote>shop</quote> and <quote>fragile</quote> are typically used for
6219 <quote>problem</quote> sites that require more than one action to be disabled
6220 in order to function properly.
6226 <!-- ~~~~~ New section ~~~~~ -->
6227 <sect2 id="act-examples">
6228 <title>Actions Files Tutorial</title>
6230 The above chapters have shown <link linkend="actions-file">which actions files
6231 there are and how they are organized</link>, how actions are <link
6232 linkend="actions">specified</link> and <link linkend="actions-apply">applied
6233 to URLs</link>, how <link linkend="af-patterns">patterns</link> work, and how to
6234 define and use <link linkend="aliases">aliases</link>. Now, let's look at an
6235 example <filename>default.action</filename> and <filename>user.action</filename>
6236 file and see how all these pieces come together:
6239 <sect3><title>default.action</title>
6242 Every config file should start with a short comment stating its purpose:
6246 <screen># Sample default.action file <ijbswa-developers@lists.sourceforge.net></screen>
6250 Then, since this is the <filename>default.action</filename> file, the
6251 first section is a special section for internal use that you needn't
6252 change or worry about:
6257 ##########################################################################
6258 # Settings -- Don't change! For internal Privoxy use ONLY.
6259 ##########################################################################
6262 for-privoxy-version=3.0</screen>
6266 After that comes the (optional) alias section. We'll use the example
6267 section from the above <link linkend="aliases">chapter on aliases</link>,
6268 that also explains why and how aliases are used:
6273 ##########################################################################
6275 ##########################################################################
6278 # These aliases just save typing later:
6279 # (Note that some already use other aliases!)
6281 +crunch-all-cookies = +<link linkend="CRUNCH-INCOMING-COOKIES">crunch-incoming-cookies</link> +<link linkend="CRUNCH-OUTGOING-COOKIES">crunch-outgoing-cookies</link>
6282 -crunch-all-cookies = -<link linkend="CRUNCH-INCOMING-COOKIES">crunch-incoming-cookies</link> -<link linkend="CRUNCH-OUTGOING-COOKIES">crunch-outgoing-cookies</link>
6283 +block-as-image = +block +handle-as-image
6284 mercy-for-cookies = -crunch-all-cookies -<link linkend="SESSION-COOKIES-ONLY">session-cookies-only</link> -<link linkend="FILTER-CONTENT-COOKIES">filter{content-cookies}</link>
6286 # These aliases define combinations of actions
6287 # that are useful for certain types of sites:
6289 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>
6290 shop = -crunch-all-cookies -<link linkend="FILTER-ALL-POPUPS">filter{all-popups}</link> -<link linkend="KILL-POPUPS">kill-popups</link></screen>
6294 Now come the regular sections, i.e. sets of actions, accompanied
6295 by URL patterns to which they apply. Remember <emphasis>all actions
6296 are disabled when matching starts</emphasis>, so we have to explicitly
6297 enable the ones we want.
6301 The first regular section is probably the most important. It has only
6302 one pattern, <quote><literal>/</literal></quote>, but this pattern
6303 <link linkend="af-patterns">matches all URLs</link>. Therefore, the
6304 set of actions used in this <quote>default</quote> section <emphasis>will
6305 be applied to all requests as a start</emphasis>. It can be partly or
6306 wholly overridden by later matches further down this file, or in user.action,
6307 but it will still be largely responsible for your overall browsing
6312 Again, at the start of matching, all actions are disabled, so there is
6313 no need to disable any actions here. (Remember: a <quote>+</quote>
6314 preceding the action name enables the action, a <quote>-</quote> disables!).
6315 Also note how this long line has been made more readable by splitting it into
6316 multiple lines with line continuation.
6321 ##########################################################################
6322 # "Defaults" section:
6323 ##########################################################################
6325 +<link linkend="DEANIMATE-GIFS">deanimate-gifs</link> \
6326 +<link linkend="FILTER-HTML-ANNOYANCES">filter{html-annoyances}</link> \
6327 +<link linkend="FILTER-REFRESH-TAGS">filter{refresh-tags}</link> \
6328 +<link linkend="FILTER-WEBBUGS">filter{webbugs}</link> \
6329 +<link linkend="FILTER-IE-EXPLOITS">filter{ie-exploits}</link> \
6330 +<link linkend="HIDE-FORWARDED-FOR-HEADERS">hide-forwarded-for-headers</link> \
6331 +<link linkend="HIDE-FROM-HEADER">hide-from-header{block}</link> \
6332 +<link linkend="HIDE-REFERER">hide-referrer{forge}</link> \
6333 +<link linkend="PREVENT-COMPRESSION">prevent-compression</link> \
6334 +<link linkend="SESSION-COOKIES-ONLY">session-cookies-only</link> \
6335 +<link linkend="SET-IMAGE-BLOCKER">set-image-blocker{pattern}</link> \
6337 / # forward slash will match *all* potential URL patterns.</screen>
6341 The default behavior is now set.
6343 This needs rewording, but it can wait for now.
6346 Note that some actions, like not hiding
6347 the user agent, are part of a <quote>general policy</quote> that applies
6348 universally and won't get any exceptions defined later. Other choices,
6349 like not blocking (which is <emphasis>understandably</emphasis> the
6350 default!) need exceptions, i.e. we need to specify explicitly what we
6351 want to block in later sections.
6356 The first of our specialized sections is concerned with <quote>fragile</quote>
6357 sites, i.e. sites that require minimum interference, because they are either
6358 very complex or very keen on tracking you (and have mechanisms in place that
6359 make them unusable for people who avoid being tracked). We will simply use
6360 our pre-defined <literal>fragile</literal> alias instead of stating the list
6361 of actions explicitly:
6366 ##########################################################################
6367 # Exceptions for sites that'll break under the default action set:
6368 ##########################################################################
6370 # "Fragile" Use a minimum set of actions for these sites (see alias above):
6373 .office.microsoft.com # surprise, surprise!
6374 .windowsupdate.microsoft.com
6375 mail.google.com</screen>
6379 Shopping sites are not as fragile, but they typically
6380 require cookies to log in, and pop-up windows for shopping
6381 carts or item details. Again, we'll use a pre-defined alias:
6390 .worldpay.com # for quietpc.com
6392 .scan.co.uk</screen>
6395 <!-- No longer needed BEGIN OF COMMENTED OUT BLOCK
6398 Then, there are sites which rely on pop-up windows (yuck!) to work.
6399 Since we made pop-up-killing our default above, we need to make exceptions
6400 now. <ulink url="http://www.mozilla.org/">Mozilla</ulink> users, who
6401 can turn on smart handling of unwanted pop-ups in their browsers, can
6403 -<literal><link linkend="FILTER-ALL-POPUPS">filter{popups}</link></literal> (and
6404 -<literal><link linkend="KILL-POPUPS">kill-popups</link></literal>) above
6405 and hence don't need this section. Anyway, disabling an already disabled
6406 action doesn't hurt, so we'll define our exceptions regardless of what was
6407 chosen in the defaults section:
6412 # These sites require pop-ups too :(
6414 { -<link linkend="KILL-POPUPS">kill-popups</link> -<link linkend="FILTER-ALL-POPUPS">filter{popups}</link> }
6417 .deutsche-bank-24.de</screen>
6420 END OF COMMENTED OUT BLOCK -->
6423 The <literal><link linkend="FAST-REDIRECTS">fast-redirects</link></literal>
6424 action, which we enabled per default above, breaks some sites. So disable
6425 it for popular sites where we know it misbehaves:
6430 { -<link linkend="FAST-REDIRECTS">fast-redirects</link> }
6434 .altavista.com/.*(like|url|link):http
6435 .altavista.com/trans.*urltext=http
6436 .nytimes.com</screen>
6440 It is important that <application>Privoxy</application> knows which
6441 URLs belong to images, so that <emphasis>if</emphasis> they are to
6442 be blocked, a substitute image can be sent, rather than an HTML page.
6443 Contacting the remote site to find out is not an option, since it
6444 would destroy the loading time advantage of banner blocking, and it
6445 would feed the advertisers (in terms of money <emphasis>and</emphasis>
6446 information). We can mark any URL as an image with the <literal><link
6447 linkend="handle-as-image">handle-as-image</link></literal> action,
6448 and marking all URLs that end in a known image file extension is a
6454 ##########################################################################
6456 ##########################################################################
6458 # Define which file types will be treated as images, in case they get
6459 # blocked further down this file:
6461 { +<link linkend="HANDLE-AS-IMAGE">handle-as-image</link> }
6462 /.*\.(gif|jpe?g|png|bmp|ico)$</screen>
6466 And then there are known banner sources. They often use scripts to
6467 generate the banners, so it won't be visible from the URL that the
6468 request is for an image. Hence we block them <emphasis>and</emphasis>
6469 mark them as images in one go, with the help of our
6470 <literal>+block-as-image</literal> alias defined above. (We could of
6471 course just as well use <literal>+<link linkend="block">block</link>
6472 +<link linkend="handle-as-image">handle-as-image</link></literal> here.)
6473 Remember that the type of the replacement image is chosen by the
6474 <literal><link linkend="set-image-blocker">set-image-blocker</link></literal>
6475 action. Since all URLs have matched the default section with its
6476 <literal>+<link linkend="set-image-blocker">set-image-blocker</link>{pattern}</literal>
6477 action before, it still applies and needn't be repeated:
6482 # Known ad generators:
6487 .ad.*.doubleclick.net
6488 .a.yimg.com/(?:(?!/i/).)*$
6489 .a[0-9].yimg.com/(?:(?!/i/).)*$
6495 One of the most important jobs of <application>Privoxy</application>
6496 is to block banners. Many of these can be <quote>blocked</quote>
6497 by the <literal><link linkend="filter">filter</link>{banners-by-size}</literal>
6498 action, which we enabled above, and which deletes the references to banner
6499 images from the pages while they are loaded, so the browser doesn't request
6500 them anymore, and hence they don't need to be blocked here. But this naturally
6501 doesn't catch all banners, and some people choose not to use filters, so we
6502 need a comprehensive list of patterns for banner URLs here, and apply the
6503 <literal><link linkend="block">block</link></literal> action to them.
6506 First comes many generic patterns, which do most of the work, by
6507 matching typical domain and path name components of banners. Then comes
6508 a list of individual patterns for specific sites, which is omitted here
6509 to keep the example short:
6514 ##########################################################################
6515 # Block these fine banners:
6516 ##########################################################################
6517 { <link linkend="BLOCK">+block</link> }
6525 /.*count(er)?\.(pl|cgi|exe|dll|asp|php[34]?)
6526 /(?:.*/)?(publicite|werbung|rekla(ma|me|am)|annonse|maino(kset|nta|s)?)/
6528 # Site-specific patterns (abbreviated):
6530 .hitbox.com</screen>
6534 It's quite remarkable how many advertisers actually call their banner
6535 servers ads.<replaceable>company</replaceable>.com, or call the directory
6536 in which the banners are stored simply <quote>banners</quote>. So the above
6537 generic patterns are surprisingly effective.
6540 But being very generic, they necessarily also catch URLs that we don't want
6541 to block. The pattern <literal>.*ads.</literal> e.g. catches
6542 <quote>nasty-<emphasis>ads</emphasis>.nasty-corp.com</quote> as intended,
6543 but also <quote>downlo<emphasis>ads</emphasis>.sourcefroge.net</quote> or
6544 <quote><emphasis>ads</emphasis>l.some-provider.net.</quote> So here come some
6545 well-known exceptions to the <literal>+<link linkend="BLOCK">block</link></literal>
6549 Note that these are exceptions to exceptions from the default! Consider the URL
6550 <quote>downloads.sourcefroge.net</quote>: Initially, all actions are deactivated,
6551 so it wouldn't get blocked. Then comes the defaults section, which matches the
6552 URL, but just deactivates the <literal><link linkend="BLOCK">block</link></literal>
6553 action once again. Then it matches <literal>.*ads.</literal>, an exception to the
6554 general non-blocking policy, and suddenly
6555 <literal><link linkend="BLOCK">+block</link></literal> applies. And now, it'll match
6556 <literal>.*loads.</literal>, where <literal><link linkend="BLOCK">-block</link></literal>
6557 applies, so (unless it matches <emphasis>again</emphasis> further down) it ends up
6558 with no <literal><link linkend="BLOCK">block</link></literal> action applying.
6563 ##########################################################################
6564 # Save some innocent victims of the above generic block patterns:
6565 ##########################################################################
6569 { -<link linkend="BLOCK">block</link> }
6570 adv[io]*. # (for advogato.org and advice.*)
6571 adsl. # (has nothing to do with ads)
6572 adobe. # (has nothing to do with ads either)
6573 ad[ud]*. # (adult.* and add.*)
6574 .edu # (universities don't host banners (yet!))
6575 .*loads. # (downloads, uploads etc)
6583 www.globalintersec.com/adv # (adv = advanced)
6584 www.ugu.com/sui/ugu/adv</screen>
6588 Filtering source code can have nasty side effects,
6589 so make an exception for our friends at sourceforge.net,
6590 and all paths with <quote>cvs</quote> in them. Note that
6591 <literal>-<link linkend="FILTER">filter</link></literal>
6592 disables <emphasis>all</emphasis> filters in one fell swoop!
6597 # Don't filter code!
6599 { -<link linkend="FILTER">filter</link> }
6604 .sourceforge.net</screen>
6608 The actual <filename>default.action</filename> is of course much more
6609 comprehensive, but we hope this example made clear how it works.
6614 <sect3><title>user.action</title>
6617 So far we are painting with a broad brush by setting general policies,
6618 which would be a reasonable starting point for many people. Now,
6619 you might want to be more specific and have customized rules that
6620 are more suitable to your personal habits and preferences. These would
6621 be for narrowly defined situations like your ISP or your bank, and should
6622 be placed in <filename>user.action</filename>, which is parsed after all other
6623 actions files and hence has the last word, over-riding any previously
6624 defined actions. <filename>user.action</filename> is also a
6625 <emphasis>safe</emphasis> place for your personal settings, since
6626 <filename>default.action</filename> is actively maintained by the
6627 <application>Privoxy</application> developers and you'll probably want
6628 to install updated versions from time to time.
6632 So let's look at a few examples of things that one might typically do in
6633 <filename>user.action</filename>:
6637 <!-- brief sample user.action here -->
6641 # My user.action file. <fred@example.com></screen>
6645 As <link linkend="aliases">aliases</link> are local to the actions
6646 file that they are defined in, you can't use the ones from
6647 <filename>default.action</filename>, unless you repeat them here:
6652 # Aliases are local to the file they are defined in.
6653 # (Re-)define aliases for this file:
6657 # These aliases just save typing later, and the alias names should
6658 # be self explanatory.
6660 +crunch-all-cookies = +crunch-incoming-cookies +crunch-outgoing-cookies
6661 -crunch-all-cookies = -crunch-incoming-cookies -crunch-outgoing-cookies
6662 allow-all-cookies = -crunch-all-cookies -session-cookies-only
6663 allow-popups = -filter{all-popups} -kill-popups
6664 +block-as-image = +block +handle-as-image
6665 -block-as-image = -block
6667 # These aliases define combinations of actions that are useful for
6668 # certain types of sites:
6670 fragile = -block -crunch-all-cookies -filter -fast-redirects -hide-referrer -kill-popups
6671 shop = -crunch-all-cookies allow-popups
6673 # Allow ads for selected useful free sites:
6675 allow-ads = -block -filter{banners-by-size} -filter{banners-by-link}
6677 # Alias for specific file types that are text, but might have conflicting
6678 # MIME types. We want the browser to force these to be text documents.
6679 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>
6684 Say you have accounts on some sites that you visit regularly, and
6685 you don't want to have to log in manually each time. So you'd like
6686 to allow persistent cookies for these sites. The
6687 <literal>allow-all-cookies</literal> alias defined above does exactly
6688 that, i.e. it disables crunching of cookies in any direction, and the
6689 processing of cookies to make them only temporary.
6694 { allow-all-cookies }
6698 .redhat.com</screen>
6702 Your bank is allergic to some filter, but you don't know which, so you disable them all:
6707 { -<link linkend="FILTER">filter</link> }
6708 .your-home-banking-site.com</screen>
6712 Some file types you may not want to filter for various reasons:
6717 # Technical documentation is likely to contain strings that might
6718 # erroneously get altered by the JavaScript-oriented filters:
6723 # And this stupid host sends streaming video with a wrong MIME type,
6724 # so that Privoxy thinks it is getting HTML and starts filtering:
6726 stupid-server.example.com/</screen>
6730 Example of a simple <link linkend="BLOCK">block</link> action. Say you've
6731 seen an ad on your favourite page on example.com that you want to get rid of.
6732 You have right-clicked the image, selected <quote>copy image location</quote>
6733 and pasted the URL below while removing the leading http://, into a
6734 <literal>{ +block }</literal> section. Note that <literal>{ +handle-as-image
6735 }</literal> need not be specified, since all URLs ending in
6736 <literal>.gif</literal> will be tagged as images by the general rules as set
6737 in default.action anyway:
6742 { +<link linkend="BLOCK">block</link> }
6743 www.example.com/nasty-ads/sponsor\.gif
6744 another.example.net/more/junk/here/</screen>
6748 The URLs of dynamically generated banners, especially from large banner
6749 farms, often don't use the well-known image file name extensions, which
6750 makes it impossible for <application>Privoxy</application> to guess
6751 the file type just by looking at the URL.
6752 You can use the <literal>+block-as-image</literal> alias defined above for
6754 Note that objects which match this rule but then turn out NOT to be an
6755 image are typically rendered as a <quote>broken image</quote> icon by the
6756 browser. Use cautiously.
6765 ar.atwola.com/</screen>
6769 Now you noticed that the default configuration breaks Forbes Magazine,
6770 but you were too lazy to find out which action is the culprit, and you
6771 were again too lazy to give <link linkend="contact">feedback</link>, so
6772 you just used the <literal>fragile</literal> alias on the site, and
6773 -- <emphasis>whoa!</emphasis> -- it worked. The <literal>fragile</literal>
6774 aliases disables those actions that are most likely to break a site. Also,
6775 good for testing purposes to see if it is <application>Privoxy</application>
6776 that is causing the problem or not. We later find other regular sites
6777 that misbehave, and add those to our personalized list of troublemakers:
6785 .mybank.com</screen>
6789 You like the <quote>fun</quote> text replacements in <filename>default.filter</filename>,
6790 but it is disabled in the distributed actions file.
6791 So you'd like to turn it on in your private,
6792 update-safe config, once and for all:
6797 { +<link linkend="filter-fun">filter{fun}</link> }
6798 / # For ALL sites!</screen>
6802 Note that the above is not really a good idea: There are exceptions
6803 to the filters in <filename>default.action</filename> for things that
6804 really shouldn't be filtered, like code on CVS->Web interfaces. Since
6805 <filename>user.action</filename> has the last word, these exceptions
6806 won't be valid for the <quote>fun</quote> filtering specified here.
6810 You might also worry about how your favourite free websites are
6811 funded, and find that they rely on displaying banner advertisements
6812 to survive. So you might want to specifically allow banners for those
6813 sites that you feel provide value to you:
6825 Note that <literal>allow-ads</literal> has been aliased to
6826 <literal>-<link linkend="block">block</link></literal>,
6827 <literal>-<link linkend="filter-banners-by-size">filter{banners-by-size}</link></literal>, and
6828 <literal>-<link linkend="filter-banners-by-link">filter{banners-by-link}</link></literal> above.
6832 Invoke another alias here to force an over-ride of the MIME type <literal>
6833 application/x-sh</literal> which typically would open a download type
6834 dialog. In my case, I want to look at the shell script, and then I can save
6835 it should I choose to.
6845 <filename>user.action</filename> is generally the best place to define
6846 exceptions and additions to the default policies of
6847 <filename>default.action</filename>. Some actions are safe to have their
6848 default policies set here though. So let's set a default policy to have a
6849 <quote>blank</quote> image as opposed to the checkerboard pattern for
6850 <emphasis>ALL</emphasis> sites. <quote>/</quote> of course matches all URL
6856 { +<link linkend="set-image-blocker">set-image-blocker{blank}</link> }
6857 / # ALL sites</screen>
6863 <!-- ~ End section ~ -->
6867 <!-- ~ End section ~ -->
6869 <!-- ~~~~~~~~ New section Header ~~~~~~~~~ -->
6871 <sect1 id="filter-file">
6872 <title>Filter Files</title>
6875 On-the-fly text substitutions need
6876 to be defined in a <quote>filter file</quote>. Once defined, they
6877 can then be invoked as an <quote>action</quote>.
6881 &my-app; supports three different filter actions:
6882 <literal><link linkend="filter">filter</link></literal> to
6883 rewrite the content that is send to the client,
6884 <literal><link linkend="client-header-filter">client-header-filter</link></literal>
6885 to rewrite headers that are send by the client, and
6886 <literal><link linkend="server-header-filter">server-header-filter</link></literal>
6887 to rewrite headers that are send by the server.
6891 &my-app; also supports two tagger actions:
6892 <literal><link linkend="client-header-tagger">client-header-tagger</link></literal>
6894 <literal><link linkend="server-header-tagger">server-header-tagger</link></literal>.
6895 Taggers and filters use the same syntax in the filter files, the difference
6896 is that taggers don't modify the text they are filtering, but use a rewritten
6897 version of the filtered text as tag. The tags can then be used to change the
6898 applying actions through sections with <link linkend="tag-pattern">tag-patterns</link>.
6903 Multiple filter files can be defined through the <literal> <link
6904 linkend="filterfile">filterfile</link></literal> config directive. The filters
6905 as supplied by the developers are located in
6906 <filename>default.filter</filename>. It is recommended that any locally
6907 defined or modified filters go in a separately defined file such as
6908 <filename>user.filter</filename>.
6912 Common tasks for content filters are to eliminate common annoyances in
6913 HTML and JavaScript, such as pop-up windows,
6914 exit consoles, crippled windows without navigation tools, the
6915 infamous <BLINK> tag etc, to suppress images with certain
6916 width and height attributes (standard banner sizes or web-bugs),
6917 or just to have fun.
6921 Enabled content filters are applied to any content whose
6922 <quote>Content Type</quote> header is recognised as a sign
6923 of text-based content, with the exception of <literal>text/plain</literal>.
6924 Use the <link linkend="FORCE-TEXT-MODE">force-text-mode</link> action
6925 to also filter other content.
6929 Substitutions are made at the source level, so if you want to <quote>roll
6930 your own</quote> filters, you should first be familiar with HTML syntax,
6931 and, of course, regular expressions.
6935 Just like the <link linkend="actions-file">actions files</link>, the
6936 filter file is organized in sections, which are called <emphasis>filters</emphasis>
6937 here. Each filter consists of a heading line, that starts with one of the
6938 <emphasis>keywords</emphasis> <literal>FILTER:</literal>,
6939 <literal>CLIENT-HEADER-FILTER:</literal> or <literal>SERVER-HEADER-FILTER:</literal>
6940 followed by the filter's <emphasis>name</emphasis>, and a short (one line)
6941 <emphasis>description</emphasis> of what it does. Below that line
6942 come the <emphasis>jobs</emphasis>, i.e. lines that define the actual
6943 text substitutions. By convention, the name of a filter
6944 should describe what the filter <emphasis>eliminates</emphasis>. The
6945 comment is used in the <ulink url="http://config.privoxy.org/">web-based
6946 user interface</ulink>.
6950 Once a filter called <replaceable>name</replaceable> has been defined
6951 in the filter file, it can be invoked by using an action of the form
6952 +<literal><link linkend="filter">filter</link>{<replaceable>name</replaceable>}</literal>
6953 in any <link linkend="actions-file">actions file</link>.
6957 Filter definitions start with a header line that contains the filter
6958 type, the filter name and the filter description.
6959 A content filter header line for a filter called <quote>foo</quote> could look
6964 <screen>FILTER: foo Replace all "foo" with "bar"</screen>
6968 Below that line, and up to the next header line, come the jobs that
6969 define what text replacements the filter executes. They are specified
6970 in a syntax that imitates <ulink url="http://www.perl.org/">Perl</ulink>'s
6971 <literal>s///</literal> operator. If you are familiar with Perl, you
6972 will find this to be quite intuitive, and may want to look at the
6973 PCRS documentation for the subtle differences to Perl behaviour. Most
6974 notably, the non-standard option letter <literal>U</literal> is supported,
6975 which turns the default to ungreedy matching.
6980 <ulink url="http://en.wikipedia.org/wiki/Regular_expressions"><quote>Regular
6981 Expressions</quote></ulink>, you might want to take a look at
6982 the <link linkend="regex">Appendix on regular expressions</link>, and
6983 see the <ulink url="http://perldoc.perl.org/perlre.html">Perl
6985 <ulink url="http://perldoc.perl.org/perlop.html">the
6986 <literal>s///</literal> operator's syntax</ulink> and <ulink
6987 url="http://perldoc.perl.org/perlre.html">Perl-style regular
6988 expressions</ulink> in general.
6989 The below examples might also help to get you started.
6993 <!-- ~~~~~~~~ New section Header ~~~~~~~~~ -->
6995 <sect2><title>Filter File Tutorial</title>
6997 Now, let's complete our <quote>foo</quote> content filter. We have already defined
6998 the heading, but the jobs are still missing. Since all it does is to replace
6999 <quote>foo</quote> with <quote>bar</quote>, there is only one (trivial) job
7004 <screen>s/foo/bar/</screen>
7008 But wait! Didn't the comment say that <emphasis>all</emphasis> occurrences
7009 of <quote>foo</quote> should be replaced? Our current job will only take
7010 care of the first <quote>foo</quote> on each page. For global substitution,
7011 we'll need to add the <literal>g</literal> option:
7015 <screen>s/foo/bar/g</screen>
7019 Our complete filter now looks like this:
7022 <screen>FILTER: foo Replace all "foo" with "bar"
7023 s/foo/bar/g</screen>
7027 Let's look at some real filters for more interesting examples. Here you see
7028 a filter that protects against some common annoyances that arise from JavaScript
7029 abuse. Let's look at its jobs one after the other:
7035 FILTER: js-annoyances Get rid of particularly annoying JavaScript abuse
7037 # Get rid of JavaScript referrer tracking. Test page: http://www.randomoddness.com/untitled.htm
7039 s|(<script.*)document\.referrer(.*</script>)|$1"Not Your Business!"$2|Usg</screen>
7043 Following the header line and a comment, you see the job. Note that it uses
7044 <literal>|</literal> as the delimiter instead of <literal>/</literal>, because
7045 the pattern contains a forward slash, which would otherwise have to be escaped
7046 by a backslash (<literal>\</literal>).
7050 Now, let's examine the pattern: it starts with the text <literal><script.*</literal>
7051 enclosed in parentheses. Since the dot matches any character, and <literal>*</literal>
7052 means: <quote>Match an arbitrary number of the element left of myself</quote>, this
7053 matches <quote><script</quote>, followed by <emphasis>any</emphasis> text, i.e.
7054 it matches the whole page, from the start of the first <script> tag.
7058 That's more than we want, but the pattern continues: <literal>document\.referrer</literal>
7059 matches only the exact string <quote>document.referrer</quote>. The dot needed to
7060 be <emphasis>escaped</emphasis>, i.e. preceded by a backslash, to take away its
7061 special meaning as a joker, and make it just a regular dot. So far, the meaning is:
7062 Match from the start of the first <script> tag in a the page, up to, and including,
7063 the text <quote>document.referrer</quote>, if <emphasis>both</emphasis> are present
7064 in the page (and appear in that order).
7068 But there's still more pattern to go. The next element, again enclosed in parentheses,
7069 is <literal>.*</script></literal>. You already know what <literal>.*</literal>
7070 means, so the whole pattern translates to: Match from the start of the first <script>
7071 tag in a page to the end of the last <script> tag, provided that the text
7072 <quote>document.referrer</quote> appears somewhere in between.
7076 This is still not the whole story, since we have ignored the options and the parentheses:
7077 The portions of the page matched by sub-patterns that are enclosed in parentheses, will be
7078 remembered and be available through the variables <literal>$1, $2, ...</literal> in
7079 the substitute. The <literal>U</literal> option switches to ungreedy matching, which means
7080 that the first <literal>.*</literal> in the pattern will only <quote>eat up</quote> all
7081 text in between <quote><script</quote> and the <emphasis>first</emphasis> occurrence
7082 of <quote>document.referrer</quote>, and that the second <literal>.*</literal> will
7083 only span the text up to the <emphasis>first</emphasis> <quote></script></quote>
7084 tag. Furthermore, the <literal>s</literal> option says that the match may span
7085 multiple lines in the page, and the <literal>g</literal> option again means that the
7086 substitution is global.
7090 So, to summarize, the pattern means: Match all scripts that contain the text
7091 <quote>document.referrer</quote>. Remember the parts of the script from
7092 (and including) the start tag up to (and excluding) the string
7093 <quote>document.referrer</quote> as <literal>$1</literal>, and the part following
7094 that string, up to and including the closing tag, as <literal>$2</literal>.
7098 Now the pattern is deciphered, but wasn't this about substituting things? So
7099 lets look at the substitute: <literal>$1"Not Your Business!"$2</literal> is
7100 easy to read: The text remembered as <literal>$1</literal>, followed by
7101 <literal>"Not Your Business!"</literal> (<emphasis>including</emphasis>
7102 the quotation marks!), followed by the text remembered as <literal>$2</literal>.
7103 This produces an exact copy of the original string, with the middle part
7104 (the <quote>document.referrer</quote>) replaced by <literal>"Not Your
7105 Business!"</literal>.
7109 The whole job now reads: Replace <quote>document.referrer</quote> by
7110 <literal>"Not Your Business!"</literal> wherever it appears inside a
7111 <script> tag. Note that this job won't break JavaScript syntax,
7112 since both the original and the replacement are syntactically valid
7113 string objects. The script just won't have access to the referrer
7114 information anymore.
7118 We'll show you two other jobs from the JavaScript taming department, but
7119 this time only point out the constructs of special interest:
7124 # The status bar is for displaying link targets, not pointless blahblah
7126 s/window\.status\s*=\s*(['"]).*?\1/dUmMy=1/ig</screen>
7130 <literal>\s</literal> stands for whitespace characters (space, tab, newline,
7131 carriage return, form feed), so that <literal>\s*</literal> means: <quote>zero
7132 or more whitespace</quote>. The <literal>?</literal> in <literal>.*?</literal>
7133 makes this matching of arbitrary text ungreedy. (Note that the <literal>U</literal>
7134 option is not set). The <literal>['"]</literal> construct means: <quote>a single
7135 <emphasis>or</emphasis> a double quote</quote>. Finally, <literal>\1</literal> is
7136 a back-reference to the first parenthesis just like <literal>$1</literal> above,
7137 with the difference that in the <emphasis>pattern</emphasis>, a backslash indicates
7138 a back-reference, whereas in the <emphasis>substitute</emphasis>, it's the dollar.
7142 So what does this job do? It replaces assignments of single- or double-quoted
7143 strings to the <quote>window.status</quote> object with a dummy assignment
7144 (using a variable name that is hopefully odd enough not to conflict with
7145 real variables in scripts). Thus, it catches many cases where e.g. pointless
7146 descriptions are displayed in the status bar instead of the link target when
7147 you move your mouse over links.
7152 # Kill OnUnload popups. Yummy. Test: http://www.zdnet.com/zdsubs/yahoo/tree/yfs.html
7154 s/(<body [^>]*)onunload(.*>)/$1never$2/iU</screen>
7159 <ulink url="http://www.w3.org/TR/2000/REC-DOM-Level-2-Events-20001113/events.html#Events-eventgroupings-htmlevents">OnUnload
7160 event binding</ulink> in the HTML DOM was a <emphasis>CRIME</emphasis>.
7161 When I close a browser window, I want it to close and die. Basta.
7162 This job replaces the <quote>onunload</quote> attribute in
7163 <quote><body></quote> tags with the dummy word <literal>never</literal>.
7164 Note that the <literal>i</literal> option makes the pattern matching
7165 case-insensitive. Also note that ungreedy matching alone doesn't always guarantee
7166 a minimal match: In the first parenthesis, we had to use <literal>[^>]*</literal>
7167 instead of <literal>.*</literal> to prevent the match from exceeding the
7168 <body> tag if it doesn't contain <quote>OnUnload</quote>, but the page's
7173 The last example is from the fun department:
7178 FILTER: fun Fun text replacements
7180 # Spice the daily news:
7182 s/microsoft(?!\.com)/MicroSuck/ig</screen>
7186 Note the <literal>(?!\.com)</literal> part (a so-called negative lookahead)
7187 in the job's pattern, which means: Don't match, if the string
7188 <quote>.com</quote> appears directly following <quote>microsoft</quote>
7189 in the page. This prevents links to microsoft.com from being trashed, while
7190 still replacing the word everywhere else.
7195 # Buzzword Bingo (example for extended regex syntax)
7197 s* industry[ -]leading \
7199 | customer[ -]focused \
7200 | market[ -]driven \
7201 | award[ -]winning # Comments are OK, too! \
7202 | high[ -]performance \
7203 | solutions[ -]based \
7207 *<font color="red"><b>BINGO!</b></font> \
7212 The <literal>x</literal> option in this job turns on extended syntax, and allows for
7213 e.g. the liberal use of (non-interpreted!) whitespace for nicer formatting.
7221 <!-- ~~~~~~~~ New section Header ~~~~~~~~~ -->
7223 <sect2 id="predefined-filters"><title>The Pre-defined Filters</title>
7227 Note each filter is also listed in the +filter action section above. Please
7228 keep these listings in sync.
7233 The distribution <filename>default.filter</filename> file contains a selection of
7234 pre-defined filters for your convenience:
7239 <term><emphasis>js-annoyances</emphasis></term>
7242 The purpose of this filter is to get rid of particularly annoying JavaScript abuse.
7247 replaces JavaScript references to the browser's referrer information
7248 with the string "Not Your Business!". This compliments the <literal><link
7249 linkend="hide-referrer">hide-referrer</link></literal> action on the content level.
7254 removes the bindings to the DOM's
7255 <ulink url="http://www.w3.org/TR/2000/REC-DOM-Level-2-Events-20001113/events.html#Events-eventgroupings-htmlevents">unload
7256 event</ulink> which we feel has no right to exist and is responsible for most <quote>exit consoles</quote>, i.e.
7257 nasty windows that pop up when you close another one.
7262 removes code that causes new windows to be opened with undesired properties, such as being
7263 full-screen, non-resizeable, without location, status or menu bar etc.
7269 Use with caution. This is an aggressive filter, and can break sites that
7270 rely heavily on JavaScript.
7276 <term><emphasis>js-events</emphasis></term>
7279 This is a very radical measure. It removes virtually all JavaScript event bindings, which
7280 means that scripts can not react to user actions such as mouse movements or clicks, window
7281 resizing etc, anymore. Use with caution!
7284 We <emphasis>strongly discourage</emphasis> using this filter as a default since it breaks
7285 many legitimate scripts. It is meant for use only on extra-nasty sites (should you really
7292 <term><emphasis>html-annoyances</emphasis></term>
7295 This filter will undo many common instances of HTML based abuse.
7298 The <literal>BLINK</literal> and <literal>MARQUEE</literal> tags
7299 are neutralized (yeah baby!), and browser windows will be created as
7300 resizeable (as of course they should be!), and will have location,
7301 scroll and menu bars -- even if specified otherwise.
7307 <term><emphasis>content-cookies</emphasis></term>
7310 Most cookies are set in the HTTP dialog, where they can be intercepted
7312 <literal><link linkend="crunch-incoming-cookies">crunch-incoming-cookies</link></literal>
7313 and <literal><link linkend="crunch-outgoing-cookies">crunch-outgoing-cookies</link></literal>
7314 actions. But web sites increasingly make use of HTML meta tags and JavaScript
7315 to sneak cookies to the browser on the content level.
7318 This filter disables most HTML and JavaScript code that reads or sets
7319 cookies. It cannot detect all clever uses of these types of code, so it
7320 should not be relied on as an absolute fix. Use it wherever you would also
7321 use the cookie crunch actions.
7327 <term><emphasis>refresh tags</emphasis></term>
7330 Disable any refresh tags if the interval is greater than nine seconds (so
7331 that redirections done via refresh tags are not destroyed). This is useful
7332 for dial-on-demand setups, or for those who find this HTML feature
7339 <term><emphasis>unsolicited-popups</emphasis></term>
7342 This filter attempts to prevent only <quote>unsolicited</quote> pop-up
7343 windows from opening, yet still allow pop-up windows that the user
7344 has explicitly chosen to open. It was added in version 3.0.1,
7345 as an improvement over earlier such filters.
7348 Technical note: The filter works by redefining the window.open JavaScript
7349 function to a dummy function, <literal>PrivoxyWindowOpen()</literal>,
7350 during the loading and rendering phase of each HTML page access, and
7351 restoring the function afterward.
7354 This is recommended only for browsers that cannot perform this function
7355 reliably themselves. And be aware that some sites require such windows
7356 in order to function normally. Use with caution.
7362 <term><emphasis>all-popups</emphasis></term>
7365 Attempt to prevent <emphasis>all</emphasis> pop-up windows from opening.
7366 Note this should be used with even more discretion than the above, since
7367 it is more likely to break some sites that require pop-ups for normal
7368 usage. Use with caution.
7374 <term><emphasis>img-reorder</emphasis></term>
7377 This is a helper filter that has no value if used alone. It makes the
7378 <literal>banners-by-size</literal> and <literal>banners-by-link</literal>
7379 (see below) filters more effective and should be enabled together with them.
7385 <term><emphasis>banners-by-size</emphasis></term>
7388 This filter removes image tags purely based on what size they are. Fortunately
7389 for us, many ads and banner images tend to conform to certain standardized
7390 sizes, which makes this filter quite effective for ad stripping purposes.
7393 Occasionally this filter will cause false positives on images that are not ads,
7394 but just happen to be of one of the standard banner sizes.
7397 Recommended only for those who require extreme ad blocking. The default
7398 block rules should catch 95+% of all ads <emphasis>without</emphasis> this filter enabled.
7404 <term><emphasis>banners-by-link</emphasis></term>
7407 This is an experimental filter that attempts to kill any banners if
7408 their URLs seem to point to known or suspected click trackers. It is currently
7409 not of much value and is not recommended for use by default.
7415 <term><emphasis>webbugs</emphasis></term>
7418 Webbugs are small, invisible images (technically 1X1 GIF images), that
7419 are used to track users across websites, and collect information on them.
7420 As an HTML page is loaded by the browser, an embedded image tag causes the
7421 browser to contact a third-party site, disclosing the tracking information
7422 through the requested URL and/or cookies for that third-party domain, without
7423 the user ever becoming aware of the interaction with the third-party site.
7424 HTML-ized spam also uses a similar technique to verify email addresses.
7427 This filter removes the HTML code that loads such <quote>webbugs</quote>.
7433 <term><emphasis>tiny-textforms</emphasis></term>
7436 A rather special-purpose filter that can be used to enlarge textareas (those
7437 multi-line text boxes in web forms) and turn off hard word wrap in them.
7438 It was written for the sourceforge.net tracker system where such boxes are
7439 a nuisance, but it can be handy on other sites, too.
7442 It is not recommended to use this filter as a default.
7448 <term><emphasis>jumping-windows</emphasis></term>
7451 Many consider windows that move, or resize themselves to be abusive. This filter
7452 neutralizes the related JavaScript code. Note that some sites might not display
7453 or behave as intended when using this filter. Use with caution.
7459 <term><emphasis>frameset-borders</emphasis></term>
7462 Some web designers seem to assume that everyone in the world will view their
7463 web sites using the same browser brand and version, screen resolution etc,
7464 because only that assumption could explain why they'd use static frame sizes,
7465 yet prevent their frames from being resized by the user, should they be too
7466 small to show their whole content.
7469 This filter removes the related HTML code. It should only be applied to sites
7476 <term><emphasis>demoronizer</emphasis></term>
7479 Many Microsoft products that generate HTML use non-standard extensions (read:
7480 violations) of the ISO 8859-1 aka Latin-1 character set. This can cause those
7481 HTML documents to display with errors on standard-compliant platforms.
7484 This filter translates the MS-only characters into Latin-1 equivalents.
7485 It is not necessary when using MS products, and will cause corruption of
7486 all documents that use 8-bit character sets other than Latin-1. It's mostly
7487 worthwhile for Europeans on non-MS platforms, if weird garbage characters
7488 sometimes appear on some pages, or user agents that don't correct for this on
7491 My version of Mozilla (ancient) shows litte square boxes for quote
7492 characters, and apostrophes on moronized pages. So many pages have this, I
7493 can read them fine now. HB 08/27/06
7500 <term><emphasis>shockwave-flash</emphasis></term>
7503 A filter for shockwave haters. As the name suggests, this filter strips code
7504 out of web pages that is used to embed shockwave flash objects.
7512 <term><emphasis>quicktime-kioskmode</emphasis></term>
7515 Change HTML code that embeds Quicktime objects so that kioskmode, which
7516 prevents saving, is disabled.
7522 <term><emphasis>fun</emphasis></term>
7525 Text replacements for subversive browsing fun. Make fun of your favorite
7526 Monopolist or play buzzword bingo.
7532 <term><emphasis>crude-parental</emphasis></term>
7535 A demonstration-only filter that shows how <application>Privoxy</application>
7536 can be used to delete web content on a keyword basis.
7542 <term><emphasis>ie-exploits</emphasis></term>
7545 An experimental collection of text replacements to disable malicious HTML and JavaScript
7546 code that exploits known security holes in Internet Explorer.
7549 Presently, it only protects against Nimda and a cross-site scripting bug, and
7550 would need active maintenance to provide more substantial protection.
7556 <term><emphasis>site-specifics</emphasis></term>
7559 Some web sites have very specific problems, the cure for which doesn't apply
7560 anywhere else, or could even cause damage on other sites.
7563 This is a collection of such site-specific cures which should only be applied
7564 to the sites they were intended for, which is what the supplied
7565 <filename>default.action</filename> file does. Users shouldn't need to change
7566 anything regarding this filter.
7572 <term><emphasis>google</emphasis></term>
7575 A CSS based block for Google text ads. Also removes a width limitation
7576 and the toolbar advertisement.
7582 <term><emphasis>yahoo</emphasis></term>
7585 Another CSS based block, this time for Yahoo text ads. And removes
7586 a width limitation as well.
7592 <term><emphasis>msn</emphasis></term>
7595 Another CSS based block, this time for MSN text ads. And removes
7596 tracking URLs, as well as a width limitation.
7602 <term><emphasis>blogspot</emphasis></term>
7605 Cleans up some Blogspot blogs. Read the fine print before using this one!
7608 This filter also intentionally removes some navigation stuff and sets the
7609 page width to 100%. As a result, some rounded <quote>corners</quote> would
7610 appear to early or not at all and as fixing this would require a browser
7611 that understands background-size (CSS3), they are removed instead.
7617 <term><emphasis>xml-to-html</emphasis></term>
7620 Server-header filter to change the Content-Type from xml to html.
7626 <term><emphasis>html-to-xml</emphasis></term>
7629 Server-header filter to change the Content-Type from html to xml.
7635 <term><emphasis>no-ping</emphasis></term>
7638 Removes the non-standard <literal>ping</literal> attribute from
7639 anchor and area HTML tags.
7645 <term><emphasis>hide-tor-exit-notation</emphasis></term>
7648 Client-header filter to remove the <command>Tor</command> exit node notation
7649 found in Host and Referer headers.
7652 If &my-app; and <command>Tor</command> are chained and &my-app;
7653 is configured to use socks4a, one can use <quote>http://www.example.org.foobar.exit/</quote>
7654 to access the host <quote>www.example.org</quote> through the
7655 <command>Tor</command> exit node <quote>foobar</quote>.
7658 As the HTTP client isn't aware of this notation, it treats the
7659 whole string <quote>www.example.org.foobar.exit</quote> as host and uses it
7660 for the <quote>Host</quote> and <quote>Referer</quote> headers. From the
7661 server's point of view the resulting headers are invalid and can cause problems.
7664 An invalid <quote>Referer</quote> header can trigger <quote>hot-linking</quote>
7665 protections, an invalid <quote>Host</quote> header will make it impossible for
7666 the server to find the right vhost (several domains hosted on the same IP address).
7669 This client-header filter removes the <quote>foo.exit</quote> part in those headers
7670 to prevent the mentioned problems. Note that it only modifies
7671 the HTTP headers, it doesn't make it impossible for the server
7672 to detect your <command>Tor</command> exit node based on the IP address
7673 the request is coming from.
7680 <term><emphasis> </emphasis></term>
7694 <!-- ~ End section ~ -->
7698 <!-- ~~~~~ New section ~~~~~ -->
7700 <sect1 id="templates">
7701 <title>Privoxy's Template Files</title>
7703 All <application>Privoxy</application> built-in pages, i.e. error pages such as the
7704 <ulink url="http://show-the-404-error.page"><quote>404 - No Such Domain</quote>
7705 error page</ulink>, the <ulink
7706 url="http://ads.bannerserver.example.com/nasty-ads/sponsor.html"><quote>BLOCKED</quote>
7708 and all pages of its <ulink url="http://config.privoxy.org/">web-based
7709 user interface</ulink>, are generated from <emphasis>templates</emphasis>.
7710 (<application>Privoxy</application> must be running for the above links to work as
7715 These templates are stored in a subdirectory of the <link linkend="confdir">configuration
7716 directory</link> called <filename>templates</filename>. On Unixish platforms,
7718 <ulink url="file:///etc/privoxy/templates/"><filename>/etc/privoxy/templates/</filename></ulink>.
7722 The templates are basically normal HTML files, but with place-holders (called symbols
7723 or exports), which <application>Privoxy</application> fills at run time. It
7724 is possible to edit the templates with a normal text editor, should you want
7725 to customize them. (<emphasis>Not recommended for the casual
7726 user</emphasis>). Should you create your own custom templates, you should use
7727 the <filename>config</filename> setting <link linkend="templdir">templdir</link>
7728 to specify an alternate location, so your templates do not get overwritten
7732 Note that just like in configuration files, lines starting
7733 with <literal>#</literal> are ignored when the templates are filled in.
7737 The place-holders are of the form <literal>@name@</literal>, and you will
7738 find a list of available symbols, which vary from template to template,
7739 in the comments at the start of each file. Note that these comments are not
7740 always accurate, and that it's probably best to look at the existing HTML
7741 code to find out which symbols are supported and what they are filled in with.
7745 A special application of this substitution mechanism is to make whole
7746 blocks of HTML code disappear when a specific symbol is set. We use this
7747 for many purposes, one of them being to include the beta warning in all
7748 our user interface (CGI) pages when <application>Privoxy</application>
7749 is in an alpha or beta development stage:
7754 <!-- @if-unstable-start -->
7756 ... beta warning HTML code goes here ...
7758 <!-- if-unstable-end@ --></screen>
7762 If the "unstable" symbol is set, everything in between and including
7763 <literal>@if-unstable-start</literal> and <literal>if-unstable-end@</literal>
7764 will disappear, leaving nothing but an empty comment:
7768 <screen><!-- --></screen>
7772 There's also an if-then-else construct and an <literal>#include</literal>
7773 mechanism, but you'll sure find out if you are inclined to edit the
7778 All templates refer to a style located at
7779 <ulink url="http://config.privoxy.org/send-stylesheet"><literal>http://config.privoxy.org/send-stylesheet</literal></ulink>.
7780 This is, of course, locally served by <application>Privoxy</application>
7781 and the source for it can be found and edited in the
7782 <filename>cgi-style.css</filename> template.
7787 <!-- ~ End section ~ -->
7791 <!-- ~~~~~ New section ~~~~~ -->
7793 <sect1 id="contact"><title>Contacting the Developers, Bug Reporting and Feature
7796 <!-- Include contacting.sgml boilerplate: -->
7798 <!-- end boilerplate -->
7802 <!-- ~ End section ~ -->
7805 <!-- ~~~~~ New section ~~~~~ -->
7806 <sect1 id="copyright"><title>Privoxy Copyright, License and History</title>
7808 <!-- Include copyright.sgml: -->
7810 <!-- end copyright -->
7812 <!-- ~~~~~ New section ~~~~~ -->
7813 <sect2><title>License</title>
7814 <!-- Include copyright.sgml: -->
7816 <!-- end copyright -->
7818 <!-- ~ End section ~ -->
7821 <!-- ~~~~~ New section ~~~~~ -->
7823 <sect2 id="history"><title>History</title>
7824 <!-- Include history.sgml: -->
7826 <!-- end history -->
7829 <sect2 id="authors"><title>Authors</title>
7830 <!-- Include p-authors.sgml: -->
7832 <!-- end authors -->
7837 <!-- ~ End section ~ -->
7840 <!-- ~~~~~ New section ~~~~~ -->
7841 <sect1 id="seealso"><title>See Also</title>
7842 <!-- Include seealso.sgml: -->
7844 <!-- end seealso -->
7849 <!-- ~~~~~ New section ~~~~~ -->
7850 <sect1 id="appendix"><title>Appendix</title>
7853 <!-- ~~~~~ New section ~~~~~ -->
7855 <title>Regular Expressions</title>
7857 <application>Privoxy</application> uses Perl-style <quote>regular
7858 expressions</quote> in its <link linkend="actions-file">actions
7859 files</link> and <link linkend="filter-file">filter file</link>,
7860 through the <ulink url="http://www.pcre.org/">PCRE</ulink> and
7863 <ulink url="http://www.oesterhelt.org/pcrs/">PCRS</ulink> libraries.
7865 <application>PCRS</application> libraries.
7869 If you are reading this, you probably don't understand what <quote>regular
7870 expressions</quote> are, or what they can do. So this will be a very brief
7871 introduction only. A full explanation would require a <ulink
7872 url="http://www.oreilly.com/catalog/regex/">book</ulink> ;-)
7876 Regular expressions provide a language to describe patterns that can be
7877 run against strings of characters (letter, numbers, etc), to see if they
7878 match the string or not. The patterns are themselves (sometimes complex)
7879 strings of literal characters, combined with wild-cards, and other special
7880 characters, called meta-characters. The <quote>meta-characters</quote> have
7881 special meanings and are used to build complex patterns to be matched against.
7882 Perl Compatible Regular Expressions are an especially convenient
7883 <quote>dialect</quote> of the regular expression language.
7887 To make a simple analogy, we do something similar when we use wild-card
7888 characters when listing files with the <command>dir</command> command in DOS.
7889 <literal>*.*</literal> matches all filenames. The <quote>special</quote>
7890 character here is the asterisk which matches any and all characters. We can be
7891 more specific and use <literal>?</literal> to match just individual
7892 characters. So <quote>dir file?.text</quote> would match
7893 <quote>file1.txt</quote>, <quote>file2.txt</quote>, etc. We are pattern
7894 matching, using a similar technique to <quote>regular expressions</quote>!
7898 Regular expressions do essentially the same thing, but are much, much more
7899 powerful. There are many more <quote>special characters</quote> and ways of
7900 building complex patterns however. Let's look at a few of the common ones,
7901 and then some examples:
7906 <emphasis>.</emphasis> - Matches any single character, e.g. <quote>a</quote>,
7907 <quote>A</quote>, <quote>4</quote>, <quote>:</quote>, or <quote>@</quote>.
7909 </simplelist></para>
7913 <emphasis>?</emphasis> - The preceding character or expression is matched ZERO or ONE
7916 </simplelist></para>
7920 <emphasis>+</emphasis> - The preceding character or expression is matched ONE or MORE
7923 </simplelist></para>
7927 <emphasis>*</emphasis> - The preceding character or expression is matched ZERO or MORE
7930 </simplelist></para>
7934 <emphasis>\</emphasis> - The <quote>escape</quote> character denotes that
7935 the following character should be taken literally. This is used where one of the
7936 special characters (e.g. <quote>.</quote>) needs to be taken literally and
7937 not as a special meta-character. Example: <quote>example\.com</quote>, makes
7938 sure the period is recognized only as a period (and not expanded to its
7939 meta-character meaning of any single character).
7941 </simplelist></para>
7945 <emphasis>[ ]</emphasis> - Characters enclosed in brackets will be matched if
7946 any of the enclosed characters are encountered. For instance, <quote>[0-9]</quote>
7947 matches any numeric digit (zero through nine). As an example, we can combine
7948 this with <quote>+</quote> to match any digit one of more times: <quote>[0-9]+</quote>.
7950 </simplelist></para>
7954 <emphasis>( )</emphasis> - parentheses are used to group a sub-expression,
7955 or multiple sub-expressions.
7957 </simplelist></para>
7961 <emphasis>|</emphasis> - The <quote>bar</quote> character works like an
7962 <quote>or</quote> conditional statement. A match is successful if the
7963 sub-expression on either side of <quote>|</quote> matches. As an example:
7964 <quote>/(this|that) example/</quote> uses grouping and the bar character
7965 and would match either <quote>this example</quote> or <quote>that
7966 example</quote>, and nothing else.
7968 </simplelist></para>
7971 These are just some of the ones you are likely to use when matching URLs with
7972 <application>Privoxy</application>, and is a long way from a definitive
7973 list. This is enough to get us started with a few simple examples which may
7974 be more illuminating:
7978 <emphasis><literal>/.*/banners/.*</literal></emphasis> - A simple example
7979 that uses the common combination of <quote>.</quote> and <quote>*</quote> to
7980 denote any character, zero or more times. In other words, any string at all.
7981 So we start with a literal forward slash, then our regular expression pattern
7982 (<quote>.*</quote>) another literal forward slash, the string
7983 <quote>banners</quote>, another forward slash, and lastly another
7984 <quote>.*</quote>. We are building
7985 a directory path here. This will match any file with the path that has a
7986 directory named <quote>banners</quote> in it. The <quote>.*</quote> matches
7987 any characters, and this could conceivably be more forward slashes, so it
7988 might expand into a much longer looking path. For example, this could match:
7989 <quote>/eye/hate/spammers/banners/annoy_me_please.gif</quote>, or just
7990 <quote>/banners/annoying.html</quote>, or almost an infinite number of other
7991 possible combinations, just so it has <quote>banners</quote> in the path
7996 And now something a little more complex:
8000 <emphasis><literal>/.*/adv((er)?ts?|ertis(ing|ements?))?/</literal></emphasis> -
8001 We have several literal forward slashes again (<quote>/</quote>), so we are
8002 building another expression that is a file path statement. We have another
8003 <quote>.*</quote>, so we are matching against any conceivable sub-path, just so
8004 it matches our expression. The only true literal that <emphasis>must
8005 match</emphasis> our pattern is <application>adv</application>, together with
8006 the forward slashes. What comes after the <quote>adv</quote> string is the
8011 Remember the <quote>?</quote> means the preceding expression (either a
8012 literal character or anything grouped with <quote>(...)</quote> in this case)
8013 can exist or not, since this means either zero or one match. So
8014 <quote>((er)?ts?|ertis(ing|ements?))</quote> is optional, as are the
8015 individual sub-expressions: <quote>(er)</quote>,
8016 <quote>(ing|ements?)</quote>, and the <quote>s</quote>. The <quote>|</quote>
8017 means <quote>or</quote>. We have two of those. For instance,
8018 <quote>(ing|ements?)</quote>, can expand to match either <quote>ing</quote>
8019 <emphasis>OR</emphasis> <quote>ements?</quote>. What is being done here, is an
8020 attempt at matching as many variations of <quote>advertisement</quote>, and
8021 similar, as possible. So this would expand to match just <quote>adv</quote>,
8022 or <quote>advert</quote>, or <quote>adverts</quote>, or
8023 <quote>advertising</quote>, or <quote>advertisement</quote>, or
8024 <quote>advertisements</quote>. You get the idea. But it would not match
8025 <quote>advertizements</quote> (with a <quote>z</quote>). We could fix that by
8026 changing our regular expression to:
8027 <quote>/.*/adv((er)?ts?|erti(s|z)(ing|ements?))?/</quote>, which would then match
8032 <emphasis><literal>/.*/advert[0-9]+\.(gif|jpe?g)</literal></emphasis> - Again
8033 another path statement with forward slashes. Anything in the square brackets
8034 <quote>[ ]</quote> can be matched. This is using <quote>0-9</quote> as a
8035 shorthand expression to mean any digit one through nine. It is the same as
8036 saying <quote>0123456789</quote>. So any digit matches. The <quote>+</quote>
8037 means one or more of the preceding expression must be included. The preceding
8038 expression here is what is in the square brackets -- in this case, any digit
8039 one through nine. Then, at the end, we have a grouping: <quote>(gif|jpe?g)</quote>.
8040 This includes a <quote>|</quote>, so this needs to match the expression on
8041 either side of that bar character also. A simple <quote>gif</quote> on one side, and the other
8042 side will in turn match either <quote>jpeg</quote> or <quote>jpg</quote>,
8043 since the <quote>?</quote> means the letter <quote>e</quote> is optional and
8044 can be matched once or not at all. So we are building an expression here to
8045 match image GIF or JPEG type image file. It must include the literal
8046 string <quote>advert</quote>, then one or more digits, and a <quote>.</quote>
8047 (which is now a literal, and not a special character, since it is escaped
8048 with <quote>\</quote>), and lastly either <quote>gif</quote>, or
8049 <quote>jpeg</quote>, or <quote>jpg</quote>. Some possible matches would
8050 include: <quote>//advert1.jpg</quote>,
8051 <quote>/nasty/ads/advert1234.gif</quote>,
8052 <quote>/banners/from/hell/advert99.jpg</quote>. It would not match
8053 <quote>advert1.gif</quote> (no leading slash), or
8054 <quote>/adverts232.jpg</quote> (the expression does not include an
8055 <quote>s</quote>), or <quote>/advert1.jsp</quote> (<quote>jsp</quote> is not
8056 in the expression anywhere).
8060 We are barely scratching the surface of regular expressions here so that you
8061 can understand the default <application>Privoxy</application>
8062 configuration files, and maybe use this knowledge to customize your own
8063 installation. There is much, much more that can be done with regular
8064 expressions. Now that you know enough to get started, you can learn more on
8069 More reading on Perl Compatible Regular expressions:
8070 <ulink url="http://perldoc.perl.org/perlre.html">http://perldoc.perl.org/perlre.html</ulink>
8074 For information on regular expression based substitutions and their applications
8075 in filters, please see the <link linkend="filter-file">filter file tutorial</link>
8080 <!-- ~ End section ~ -->
8083 <!-- ~~~~~ New section ~~~~~ -->
8085 <title>Privoxy's Internal Pages</title>
8088 Since <application>Privoxy</application> proxies each requested
8089 web page, it is easy for <application>Privoxy</application> to
8090 trap certain special URLs. In this way, we can talk directly to
8091 <application>Privoxy</application>, and see how it is
8092 configured, see how our rules are being applied, change these
8093 rules and other configuration options, and even turn
8094 <application>Privoxy's</application> filtering off, all with
8100 The URLs listed below are the special ones that allow direct access
8101 to <application>Privoxy</application>. Of course,
8102 <application>Privoxy</application> must be running to access these. If
8103 not, you will get a friendly error message. Internet access is not
8116 <ulink url="http://config.privoxy.org/">http://config.privoxy.org/</ulink>
8120 There is a shortcut: <ulink url="http://p.p/">http://p.p/</ulink> (But it
8121 doesn't provide a fall-back to a real page, in case the request is not
8122 sent through <application>Privoxy</application>)
8128 Show information about the current configuration, including viewing and
8129 editing of actions files:
8133 <ulink url="http://config.privoxy.org/show-status">http://config.privoxy.org/show-status</ulink>
8140 Show the source code version numbers:
8144 <ulink url="http://config.privoxy.org/show-version">http://config.privoxy.org/show-version</ulink>
8151 Show the browser's request headers:
8155 <ulink url="http://config.privoxy.org/show-request">http://config.privoxy.org/show-request</ulink>
8162 Show which actions apply to a URL and why:
8166 <ulink url="http://config.privoxy.org/show-url-info">http://config.privoxy.org/show-url-info</ulink>
8173 Toggle Privoxy on or off. This feature can be turned off/on in the main
8174 <filename>config</filename> file. When toggled <quote>off</quote>, <quote>Privoxy</quote>
8175 continues to run, but only as a pass-through proxy, with no actions taking
8180 <ulink url="http://config.privoxy.org/toggle">http://config.privoxy.org/toggle</ulink>
8184 Short cuts. Turn off, then on:
8188 <ulink url="http://config.privoxy.org/toggle?set=disable">http://config.privoxy.org/toggle?set=disable</ulink>
8193 <ulink url="http://config.privoxy.org/toggle?set=enable">http://config.privoxy.org/toggle?set=enable</ulink>
8202 These may be bookmarked for quick reference. See next.
8206 <sect3 id="bookmarklets">
8207 <title>Bookmarklets</title>
8209 Below are some <quote>bookmarklets</quote> to allow you to easily access a
8210 <quote>mini</quote> version of some of <application>Privoxy's</application>
8211 special pages. They are designed for MS Internet Explorer, but should work
8212 equally well in Netscape, Mozilla, and other browsers which support
8213 JavaScript. They are designed to run directly from your bookmarks - not by
8214 clicking the links below (although that should work for testing).
8217 To save them, right-click the link and choose <quote>Add to Favorites</quote>
8218 (IE) or <quote>Add Bookmark</quote> (Netscape). You will get a warning that
8219 the bookmark <quote>may not be safe</quote> - just click OK. Then you can run the
8220 Bookmarklet directly from your favorites/bookmarks. For even faster access,
8221 you can put them on the <quote>Links</quote> bar (IE) or the <quote>Personal
8222 Toolbar</quote> (Netscape), and run them with a single click.
8231 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>
8238 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>
8245 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)
8252 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>
8258 <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>
8264 <ulink url="javascript:void(window.open('http://config.privoxy.org/show-url-info?url='+escape(location.href),'Why').focus());">Privoxy - Why?</ulink>
8271 Credit: The site which gave us the general idea for these bookmarklets is
8272 <ulink url="http://www.bookmarklets.com/">www.bookmarklets.com</ulink>. They
8273 have more information about bookmarklets.
8282 <!-- ~~~~~ New section ~~~~~ -->
8284 <title>Chain of Events</title>
8286 Let's take a quick look at how some of <application>Privoxy's</application>
8287 core features are triggered, and the ensuing sequence of events when a web
8288 page is requested by your browser:
8295 First, your web browser requests a web page. The browser knows to send
8296 the request to <application>Privoxy</application>, which will in turn,
8297 relay the request to the remote web server after passing the following
8303 <application>Privoxy</application> traps any request for its own internal CGI
8304 pages (e.g <ulink url="http://p.p/">http://p.p/</ulink>) and sends the CGI page back to the browser.
8309 Next, <application>Privoxy</application> checks to see if the URL
8311 linkend="BLOCK"><quote>+block</quote></link> patterns. If
8312 so, the URL is then blocked, and the remote web server will not be contacted.
8313 <link linkend="HANDLE-AS-IMAGE"><quote>+handle-as-image</quote></link>
8315 <link linkend="HANDLE-AS-EMPTY-DOCUMENT"><quote>+handle-as-empty-document</quote></link>
8316 are then checked, and if there is no match, an
8317 HTML <quote>BLOCKED</quote> page is sent back to the browser. Otherwise, if
8318 it does match, an image is returned for the former, and an empty text
8319 document for the latter. The type of image would depend on the setting of
8320 <link linkend="SET-IMAGE-BLOCKER"><quote>+set-image-blocker</quote></link>
8321 (blank, checkerboard pattern, or an HTTP redirect to an image elsewhere).
8326 Untrusted URLs are blocked. If URLs are being added to the
8327 <filename>trust</filename> file, then that is done.
8332 If the URL pattern matches the <link
8333 linkend="FAST-REDIRECTS"><quote>+fast-redirects</quote></link> action,
8334 it is then processed. Unwanted parts of the requested URL are stripped.
8339 Now the rest of the client browser's request headers are processed. If any
8340 of these match any of the relevant actions (e.g. <link
8341 linkend="HIDE-USER-AGENT"><quote>+hide-user-agent</quote></link>,
8342 etc.), headers are suppressed or forged as determined by these actions and
8348 Now the web server starts sending its response back (i.e. typically a web
8354 First, the server headers are read and processed to determine, among other
8355 things, the MIME type (document type) and encoding. The headers are then
8356 filtered as determined by the
8357 <link linkend="CRUNCH-INCOMING-COOKIES"><quote>+crunch-incoming-cookies</quote></link>,
8358 <link linkend="SESSION-COOKIES-ONLY"><quote>+session-cookies-only</quote></link>,
8359 and <link linkend="DOWNGRADE-HTTP-VERSION"><quote>+downgrade-http-version</quote></link>
8365 If the <link linkend="KILL-POPUPS"><quote>+kill-popups</quote></link>
8366 action applies, and it is an HTML or JavaScript document, the popup-code in the
8367 response is filtered on-the-fly as it is received.
8372 If any <link linkend="FILTER"><quote>+filter</quote></link> action
8374 linkend="DEANIMATE-GIFS"><quote>+deanimate-gifs</quote></link>
8375 action applies (and the document type fits the action), the rest of the page is
8376 read into memory (up to a configurable limit). Then the filter rules (from
8377 <filename>default.filter</filename> and any other filter files) are
8378 processed against the buffered content. Filters are applied in the order
8379 they are specified in one of the filter files. Animated GIFs, if present,
8380 are reduced to either the first or last frame, depending on the action
8381 setting.The entire page, which is now filtered, is then sent by
8382 <application>Privoxy</application> back to your browser.
8385 If neither a <link linkend="FILTER"><quote>+filter</quote></link> action
8387 linkend="DEANIMATE-GIFS"><quote>+deanimate-gifs</quote></link>
8388 matches, then <application>Privoxy</application> passes the raw data through
8389 to the client browser as it becomes available.
8394 As the browser receives the now (possibly filtered) page content, it
8395 reads and then requests any URLs that may be embedded within the page
8396 source, e.g. ad images, stylesheets, JavaScript, other HTML documents (e.g.
8397 frames), sounds, etc. For each of these objects, the browser issues a
8398 separate request (this is easily viewable in <application>Privoxy's</application>
8399 logs). And each such request is in turn processed just as above. Note that a
8400 complex web page will have many, many such embedded URLs. If these
8401 secondary requests are to a different server, then quite possibly a very
8402 differing set of actions is triggered.
8409 NOTE: This is somewhat of a simplistic overview of what happens with each URL
8410 request. For the sake of brevity and simplicity, we have focused on
8411 <application>Privoxy's</application> core features only.
8417 <!-- ~~~~~ New section ~~~~~ -->
8418 <sect2 id="actionsanat">
8419 <title>Troubleshooting: Anatomy of an Action</title>
8422 The way <application>Privoxy</application> applies
8423 <link linkend="ACTIONS">actions</link> and <link linkend="FILTER">filters</link>
8424 to any given URL can be complex, and not always so
8425 easy to understand what is happening. And sometimes we need to be able to
8426 <emphasis>see</emphasis> just what <application>Privoxy</application> is
8427 doing. Especially, if something <application>Privoxy</application> is doing
8428 is causing us a problem inadvertently. It can be a little daunting to look at
8429 the actions and filters files themselves, since they tend to be filled with
8430 <link linkend="regex">regular expressions</link> whose consequences are not
8435 One quick test to see if <application>Privoxy</application> is causing a problem
8436 or not, is to disable it temporarily. This should be the first troubleshooting
8437 step. See <link linkend="bookmarklets">the Bookmarklets</link> section on a quick
8438 and easy way to do this (be sure to flush caches afterward!). Looking at the
8439 logs is a good idea too. (Note that both the toggle feature and logging are
8440 enabled via <filename>config</filename> file settings, and may need to be
8441 turned <quote>on</quote>.)
8444 Another easy troubleshooting step to try is if you have done any
8445 customization of your installation, revert back to the installed
8446 defaults and see if that helps. There are times the developers get complaints
8447 about one thing or another, and the problem is more related to a customized
8448 configuration issue.
8452 <application>Privoxy</application> also provides the
8453 <ulink url="http://config.privoxy.org/show-url-info">http://config.privoxy.org/show-url-info</ulink>
8454 page that can show us very specifically how <application>actions</application>
8455 are being applied to any given URL. This is a big help for troubleshooting.
8459 First, enter one URL (or partial URL) at the prompt, and then
8460 <application>Privoxy</application> will tell us
8461 how the current configuration will handle it. This will not
8462 help with filtering effects (i.e. the <link
8463 linkend="FILTER"><quote>+filter</quote></link> action) from
8464 one of the filter files since this is handled very
8465 differently and not so easy to trap! It also will not tell you about any other
8466 URLs that may be embedded within the URL you are testing. For instance, images
8467 such as ads are expressed as URLs within the raw page source of HTML pages. So
8468 you will only get info for the actual URL that is pasted into the prompt area
8469 -- not any sub-URLs. If you want to know about embedded URLs like ads, you
8470 will have to dig those out of the HTML source. Use your browser's <quote>View
8471 Page Source</quote> option for this. Or right click on the ad, and grab the
8476 Let's try an example, <ulink url="http://google.com">google.com</ulink>,
8477 and look at it one section at a time in a sample configuration (your real
8478 configuration may vary):
8483 Matches for http://www.google.com:
8485 In file: default.action <guibutton>[ View ]</guibutton> <guibutton>[ Edit ]</guibutton>
8487 {+deanimate-gifs {last}
8488 +fast-redirects {check-decoded-url}
8489 +filter {refresh-tags}
8490 +filter {img-reorder}
8491 +filter {banners-by-size}
8493 +filter {jumping-windows}
8494 +filter {ie-exploits}
8495 +hide-forwarded-for-headers
8496 +hide-from-header {block}
8497 +hide-referrer {forge}
8498 +session-cookies-only
8499 +set-image-blocker {pattern}
8502 { -session-cookies-only }
8508 In file: user.action <guibutton>[ View ]</guibutton> <guibutton>[ Edit ]</guibutton>
8509 (no matches in this file)
8514 This is telling us how we have defined our
8515 <link linkend="ACTIONS"><quote>actions</quote></link>, and
8516 which ones match for our test case, <quote>google.com</quote>.
8517 Displayed is all the actions that are available to us. Remember,
8518 the <literal>+</literal> sign denotes <quote>on</quote>. <literal>-</literal>
8519 denotes <quote>off</quote>. So some are <quote>on</quote> here, but many
8520 are <quote>off</quote>. Each example we try may provide a slightly different
8521 end result, depending on our configuration directives.
8525 is for our <filename>default.action</filename> file. The large, multi-line
8526 listing, is how the actions are set to match for all URLs, i.e. our default
8527 settings. If you look at your <quote>actions</quote> file, this would be the
8528 section just below the <quote>aliases</quote> section near the top. This
8529 will apply to all URLs as signified by the single forward slash at the end
8530 of the listing -- <quote> / </quote>.
8534 But we have defined additional actions that would be exceptions to these general
8535 rules, and then we list specific URLs (or patterns) that these exceptions
8536 would apply to. Last match wins. Just below this then are two explicit
8537 matches for <quote>.google.com</quote>. The first is negating our previous
8538 cookie setting, which was for <link
8539 linkend="SESSION-COOKIES-ONLY"><quote>+session-cookies-only</quote></link>
8540 (i.e. not persistent). So we will allow persistent cookies for google, at
8541 least that is how it is in this example. The second turns
8542 <emphasis>off</emphasis> any <link
8543 linkend="FAST-REDIRECTS"><quote>+fast-redirects</quote></link>
8544 action, allowing this to take place unmolested. Note that there is a leading
8545 dot here -- <quote>.google.com</quote>. This will match any hosts and
8546 sub-domains, in the google.com domain also, such as
8547 <quote>www.google.com</quote> or <quote>mail.google.com</quote>. But it would not
8548 match <quote>www.google.de</quote>! So, apparently, we have these two actions
8549 defined as exceptions to the general rules at the top somewhere in the lower
8550 part of our <filename>default.action</filename> file, and
8551 <quote>google.com</quote> is referenced somewhere in these latter sections.
8555 Then, for our <filename>user.action</filename> file, we again have no hits.
8556 So there is nothing google-specific that we might have added to our own, local
8557 configuration. If there was, those actions would over-rule any actions from
8558 previously processed files, such as <filename>default.action</filename>.
8559 <filename>user.action</filename> typically has the last word. This is the
8560 best place to put hard and fast exceptions,
8564 And finally we pull it all together in the bottom section and summarize how
8565 <application>Privoxy</application> is applying all its <quote>actions</quote>
8566 to <quote>google.com</quote>:
8577 -client-header-filter{hide-tor-exit-notation}
8578 -content-type-overwrite
8579 -crunch-client-header
8580 -crunch-if-none-match
8581 -crunch-incoming-cookies
8582 -crunch-outgoing-cookies
8583 -crunch-server-header
8584 +deanimate-gifs {last}
8585 -downgrade-http-version
8588 -filter {content-cookies}
8589 -filter {all-popups}
8590 -filter {banners-by-link}
8591 -filter {tiny-textforms}
8592 -filter {frameset-borders}
8593 -filter {demoronizer}
8594 -filter {shockwave-flash}
8595 -filter {quicktime-kioskmode}
8597 -filter {crude-parental}
8598 -filter {site-specifics}
8599 -filter {js-annoyances}
8600 -filter {html-annoyances}
8601 +filter {refresh-tags}
8602 -filter {unsolicited-popups}
8603 +filter {img-reorder}
8604 +filter {banners-by-size}
8606 +filter {jumping-windows}
8607 +filter {ie-exploits}
8614 -handle-as-empty-document
8616 -hide-accept-language
8617 -hide-content-disposition
8618 +hide-forwarded-for-headers
8619 +hide-from-header {block}
8620 -hide-if-modified-since
8621 +hide-referrer {forge}
8626 -overwrite-last-modified
8627 -prevent-compression
8631 -server-header-filter{xml-to-html}
8632 -server-header-filter{html-to-xml}
8633 -session-cookies-only
8634 +set-image-blocker {pattern}
8635 -treat-forbidden-connects-like-blocks </screen>
8639 Notice the only difference here to the previous listing, is to
8640 <quote>fast-redirects</quote> and <quote>session-cookies-only</quote>,
8641 which are activated specifically for this site in our configuration,
8642 and thus show in the <quote>Final Results</quote>.
8646 Now another example, <quote>ad.doubleclick.net</quote>:
8658 { +block +handle-as-image }
8659 .[a-vx-z]*.doubleclick.net
8664 We'll just show the interesting part here - the explicit matches. It is
8665 matched three different times. Two <quote>+block</quote> sections,
8666 and a <quote>+block +handle-as-image</quote>,
8667 which is the expanded form of one of our aliases that had been defined as:
8668 <quote>+block-as-image</quote>. (<link
8669 linkend="ALIASES"><quote>Aliases</quote></link> are defined in
8670 the first section of the actions file and typically used to combine more
8675 Any one of these would have done the trick and blocked this as an unwanted
8676 image. This is unnecessarily redundant since the last case effectively
8677 would also cover the first. No point in taking chances with these guys
8678 though ;-) Note that if you want an ad or obnoxious
8679 URL to be invisible, it should be defined as <quote>ad.doubleclick.net</quote>
8680 is done here -- as both a <link
8681 linkend="BLOCK"><quote>+block</quote></link>
8682 <emphasis>and</emphasis> an
8683 <link linkend="HANDLE-AS-IMAGE"><quote>+handle-as-image</quote></link>.
8684 The custom alias <quote><literal>+block-as-image</literal></quote> just
8685 simplifies the process and make it more readable.
8689 One last example. Let's try <quote>http://www.example.net/adsl/HOWTO/</quote>.
8690 This one is giving us problems. We are getting a blank page. Hmmm ...
8696 Matches for http://www.example.net/adsl/HOWTO/:
8698 In file: default.action <guibutton>[ View ]</guibutton> <guibutton>[ Edit ]</guibutton>
8702 -client-header-filter{hide-tor-exit-notation}
8703 -content-type-overwrite
8704 -crunch-client-header
8705 -crunch-if-none-match
8706 -crunch-incoming-cookies
8707 -crunch-outgoing-cookies
8708 -crunch-server-header
8710 -downgrade-http-version
8711 +fast-redirects {check-decoded-url}
8713 -filter {content-cookies}
8714 -filter {all-popups}
8715 -filter {banners-by-link}
8716 -filter {tiny-textforms}
8717 -filter {frameset-borders}
8718 -filter {demoronizer}
8719 -filter {shockwave-flash}
8720 -filter {quicktime-kioskmode}
8722 -filter {crude-parental}
8723 -filter {site-specifics}
8724 -filter {js-annoyances}
8725 -filter {html-annoyances}
8726 +filter {refresh-tags}
8727 -filter {unsolicited-popups}
8728 +filter {img-reorder}
8729 +filter {banners-by-size}
8731 +filter {jumping-windows}
8732 +filter {ie-exploits}
8739 -handle-as-empty-document
8741 -hide-accept-language
8742 -hide-content-disposition
8743 +hide-forwarded-for-headers
8744 +hide-from-header{block}
8745 +hide-referer{forge}
8749 -overwrite-last-modified
8750 +prevent-compression
8754 -server-header-filter{xml-to-html}
8755 -server-header-filter{html-to-xml}
8756 +session-cookies-only
8757 +set-image-blocker{blank}
8758 -treat-forbidden-connects-like-blocks }
8761 { +block +handle-as-image }
8767 Ooops, the <quote>/adsl/</quote> is matching <quote>/ads</quote> in our
8768 configuration! But we did not want this at all! Now we see why we get the
8769 blank page. It is actually triggering two different actions here, and
8770 the effects are aggregated so that the URL is blocked, and &my-app; is told
8771 to treat the block as if it were an image. But this is, of course, all wrong.
8772 We could now add a new action below this (or better in our own
8773 <filename>user.action</filename> file) that explicitly
8774 <emphasis>un</emphasis> blocks (
8775 <link linkend="BLOCK"><quote>{-block}</quote></link>) paths with
8776 <quote>adsl</quote> in them (remember, last match in the configuration
8777 wins). There are various ways to handle such exceptions. Example:
8789 Now the page displays ;-)
8790 Remember to flush your browser's caches when making these kinds of changes to
8791 your configuration to insure that you get a freshly delivered page! Or, try
8792 using <literal>Shift+Reload</literal>.
8796 But now what about a situation where we get no explicit matches like
8803 { +block +handle-as-image }
8809 That actually was very helpful and pointed us quickly to where the problem
8810 was. If you don't get this kind of match, then it means one of the default
8811 rules in the first section of <filename>default.action</filename> is causing
8812 the problem. This would require some guesswork, and maybe a little trial and
8813 error to isolate the offending rule. One likely cause would be one of the
8814 <link linkend="FILTER"><quote>+filter</quote></link> actions.
8815 These tend to be harder to troubleshoot.
8816 Try adding the URL for the site to one of aliases that turn off
8817 <link linkend="FILTER"><quote>+filter</quote></link>:
8825 .worldpay.com # for quietpc.com
8833 <quote><literal>{ shop }</literal></quote> is an <quote>alias</quote> that expands to
8834 <quote><literal>{ -filter -session-cookies-only }</literal></quote>.
8835 Or you could do your own exception to negate filtering:
8843 # Disable ALL filter actions for sites in this section
8851 This would turn off all filtering for these sites. This is best
8852 put in <filename>user.action</filename>, for local site
8853 exceptions. Note that when a simple domain pattern is used by itself (without
8854 the subsequent path portion), all sub-pages within that domain are included
8855 automatically in the scope of the action.
8859 Images that are inexplicably being blocked, may well be hitting the
8860 <link linkend="FILTER-BANNERS-BY-SIZE"><quote>+filter{banners-by-size}</quote></link>
8862 that images of certain sizes are ad banners (works well
8863 <emphasis>most of the time</emphasis> since these tend to be standardized).
8867 <quote><literal>{ fragile }</literal></quote> is an alias that disables most
8868 actions that are the most likely to cause trouble. This can be used as a
8869 last resort for problem sites.
8875 # Handle with care: easy to break
8877 mybank.example.com</screen>
8882 <emphasis>Remember to flush caches!</emphasis> Note that the
8883 <literal>mail.google</literal> reference lacks the TLD portion (e.g.
8884 <quote>.com</quote>). This will effectively match any TLD with
8885 <literal>google</literal> in it, such as <literal>mail.google.de.</literal>,
8889 If this still does not work, you will have to go through the remaining
8890 actions one by one to find which one(s) is causing the problem.
8899 This program is free software; you can redistribute it
8900 and/or modify it under the terms of the GNU General
8901 Public License as published by the Free Software
8902 Foundation; either version 2 of the License, or (at
8903 your option) any later version.
8905 This program is distributed in the hope that it will
8906 be useful, but WITHOUT ANY WARRANTY; without even the
8907 implied warranty of MERCHANTABILITY or FITNESS FOR A
8908 PARTICULAR PURPOSE. See the GNU General Public
8909 License for more details.
8911 The GNU General Public License should be included with
8912 this file. If not, you can view it at
8913 http://www.gnu.org/copyleft/gpl.html
8914 or write to the Free Software Foundation, Inc.,
8915 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
8918 $Log: user-manual.sgml,v $
8919 Revision 2.60 2008/02/11 03:40:25 markm68k
8920 more updates for mac os x
8922 Revision 2.59 2008/02/11 00:52:34 markm68k
8923 reflect new changes for mac os x
8925 Revision 2.58 2008/02/03 21:37:40 hal9
8926 Apply patch from Mark: s/OSX/OS X/
8928 Revision 2.57 2008/02/03 19:10:14 fabiankeil
8929 Mention forward-socks5.
8931 Revision 2.56 2008/01/31 19:11:35 fabiankeil
8932 Let the +client-header-filter{hide-tor-exit-notation} example apply
8933 to all requests as "tainted" Referers aren't limited to exit TLDs.
8935 Revision 2.55 2008/01/19 21:26:37 hal9
8936 Add IE7 to configuration section per Gerry.
8938 Revision 2.54 2008/01/19 17:52:39 hal9
8939 Re-commit to fix various minor issues for new release.
8941 Revision 2.53 2008/01/19 15:03:05 hal9
8942 Doc sources tagged for 3.0.8 release.
8944 Revision 2.52 2008/01/17 01:49:51 hal9
8945 Change copyright notice for docs s/2007/2008/. All these will be rebuilt soon
8948 Revision 2.51 2007/12/23 16:48:24 fabiankeil
8949 Use more precise example descriptions for the mysterious domain patterns.
8951 Revision 2.50 2007/12/08 12:44:36 fabiankeil
8952 - Remove already commented out pre-3.0.7 changes.
8953 - Update the "new log defaults" paragraph.
8955 Revision 2.49 2007/12/06 18:21:55 fabiankeil
8956 Update hide-forwarded-for-headers description.
8958 Revision 2.48 2007/11/24 19:07:17 fabiankeil
8959 - Mention request rewriting.
8960 - Enable the conditional-forge paragraph.
8963 Revision 2.47 2007/11/18 14:59:47 fabiankeil
8964 A few "Note to Upgraders" updates.
8966 Revision 2.46 2007/11/17 17:24:44 fabiankeil
8967 - Use new action defaults.
8968 - Minor fixes and rewordings.
8970 Revision 2.45 2007/11/16 11:48:46 hal9
8971 Fix one typo, and add a couple of small refinements.
8973 Revision 2.44 2007/11/15 03:30:20 hal9
8974 Results of spell check.
8976 Revision 2.43 2007/11/14 18:45:39 fabiankeil
8977 - Mention some more contributors in the "New in this Release" list.
8980 Revision 2.42 2007/11/12 03:32:40 hal9
8981 Updates for "What's New" and "Notes to Upgraders". Various other changes in
8982 preparation for new release. User Manual is almost ready.
8984 Revision 2.41 2007/11/11 16:32:11 hal9
8985 This is primarily syncing What's New and Note to Upgraders sections with the many
8986 new features and changes (gleaned from memory but mostly from ChangeLog).
8988 Revision 2.40 2007/11/10 17:10:59 fabiankeil
8989 In the first third of the file, mention several times that
8990 the action editor is disabled by default in 3.0.7 beta and later.
8992 Revision 2.39 2007/11/05 02:34:49 hal9
8993 Various changes in preparation for the upcoming release. Much yet to be done.
8995 Revision 2.38 2007/09/22 16:01:42 fabiankeil
8996 Update embedded show-url-info output.
8998 Revision 2.37 2007/08/27 16:09:55 fabiankeil
8999 Fix pre-chroot-nslookup description which I failed to
9000 copy and paste properly. Reported by Stephen Gildea.
9002 Revision 2.36 2007/08/26 16:47:14 fabiankeil
9003 Add Stephen Gildea's pre-chroot-nslookup patch [#1276666],
9004 extensive comments moved to user manual.
9006 Revision 2.35 2007/08/26 14:59:49 fabiankeil
9007 Minor rewordings and fixes.
9009 Revision 2.34 2007/08/05 15:19:50 fabiankeil
9010 - Don't claim HTTP/1.1 compliance.
9011 - Use $ in some of the path pattern examples.
9012 - Use a hide-user-agent example argument without
9013 leading and trailing space.
9014 - Make it clear that the cookie actions work with
9016 - Rephrase the inspect-jpegs text to underline
9017 that it's only meant to protect against a single
9020 Revision 2.33 2007/07/27 10:57:35 hal9
9021 Add references for user-agent strings for hide-user-agenet
9023 Revision 2.32 2007/06/07 12:36:22 fabiankeil
9024 Apply Roland's 29_usermanual.dpatch to fix a bunch
9025 of syntax errors I collected over the last months.
9027 Revision 2.31 2007/06/02 14:01:37 fabiankeil
9028 Start to document forward-override{}.
9030 Revision 2.30 2007/04/25 15:10:36 fabiankeil
9031 - Describe installation for FreeBSD.
9032 - Start to document taggers and tag patterns.
9033 - Don't confuse devils and daemons.
9035 Revision 2.29 2007/04/05 11:47:51 fabiankeil
9036 Some updates regarding header filtering,
9037 handling of compressed content and redirect's
9038 support for pcrs commands.
9040 Revision 2.28 2006/12/10 23:42:48 hal9
9041 Fix various typos reported by Adam P. Thanks.
9043 Revision 2.27 2006/11/14 01:57:47 hal9
9044 Dump all docs prior to 3.0.6 release. Various minor changes to faq and user
9047 Revision 2.26 2006/10/24 11:16:44 hal9
9050 Revision 2.25 2006/10/18 10:50:33 hal9
9051 Add note that since filters are off in Cautious, compression is ON. Turn off
9052 compression to make filters work on all sites.
9054 Revision 2.24 2006/10/03 11:13:54 hal9
9055 More references to the new filters. Include html this time around.
9057 Revision 2.23 2006/10/02 22:43:53 hal9
9058 Contains new filter definitions from Fabian, and few other miscellaneous
9061 Revision 2.22 2006/09/22 01:27:55 hal9
9062 Final commit of probably various minor changes here and there. Unless
9063 something changes this should be ready for pending release.
9065 Revision 2.21 2006/09/20 03:21:36 david__schmidt
9066 Just the tiniest tweak. Wafer thin!
9068 Revision 2.20 2006/09/10 14:53:54 hal9
9069 Results of spell check. User manual has some updates to standard.actions file
9072 Revision 2.19 2006/09/08 12:19:02 fabiankeil
9073 Adjust hide-if-modified-since example values
9074 to reflect the recent changes.
9076 Revision 2.18 2006/09/08 02:38:57 hal9
9078 -Fix a number of broken links.
9079 -Migrate the new Windows service command line options, and reference as
9081 -Rebuild so that can be used with the new "user-manual" config capabilities.
9084 Revision 2.17 2006/09/05 13:25:12 david__schmidt
9085 Add Windows service invocation stuff (duplicated) in FAQ and in user manual under Windows startup. One probably ought to reference the other.
9087 Revision 2.16 2006/09/02 12:49:37 hal9
9088 Various small updates for new actions, filterfiles, etc.
9090 Revision 2.15 2006/08/30 11:15:22 hal9
9091 More work on the new actions, especially filter-*-headers, and What's New
9092 section. User Manual is close to final form for 3.0.4 release. Some tinkering
9093 and proof reading left to do.
9095 Revision 2.14 2006/08/29 10:59:36 hal9
9096 Add a "Whats New in this release" Section. Further work on multiple filter
9097 files, and assorted other minor changes.
9099 Revision 2.13 2006/08/22 11:04:59 hal9
9100 Silence warnings and errors. This should build now. New filters were only
9101 stubbed in. More to be done.
9103 Revision 2.12 2006/08/14 08:40:39 fabiankeil
9104 Documented new actions that were part of
9105 the "minor Privoxy improvements".
9107 Revision 2.11 2006/07/18 14:48:51 david__schmidt
9108 Reorganizing the repository: swapping out what was HEAD (the old 3.1 branch)
9109 with what was really the latest development (the v_3_0_branch branch)
9111 Revision 1.123.2.43 2005/05/23 09:59:10 hal9
9114 Revision 1.123.2.42 2004/12/04 14:39:57 hal9
9115 Fix two minor typos per bug SF report.
9117 Revision 1.123.2.41 2004/03/23 12:58:42 oes
9120 Revision 1.123.2.40 2004/02/27 12:48:49 hal9
9121 Add comment re: redirecting to local file system for set-image-blocker may
9122 is dependent on browser.
9124 Revision 1.123.2.39 2004/01/30 22:31:40 oes
9125 Added a hint re bookmarklets to Quickstart section
9127 Revision 1.123.2.38 2004/01/30 16:47:51 oes
9128 Some minor clarifications
9130 Revision 1.123.2.37 2004/01/29 22:36:11 hal9
9131 Updates for no longer filtering text/plain, and demoronizer default settings,
9132 and copyright notice dates.
9134 Revision 1.123.2.36 2003/12/10 02:26:26 hal9
9135 Changed the demoronizer filter description.
9137 Revision 1.123.2.35 2003/11/06 13:36:37 oes
9138 Updated link to nightly CVS tarball
9140 Revision 1.123.2.34 2003/06/26 23:50:16 hal9
9141 Add a small bit on filtering and problems re: source code being corrupted.
9143 Revision 1.123.2.33 2003/05/08 18:17:33 roro
9144 Use apt-get instead of dpkg to install Debian package, which is more
9145 solid, uses the correct and most recent Debian version automatically.
9147 Revision 1.123.2.32 2003/04/11 03:13:57 hal9
9148 Add small note about only one filterfile (as opposed to multiple actions
9151 Revision 1.123.2.31 2003/03/26 02:03:43 oes
9152 Updated hard-coded copyright dates
9154 Revision 1.123.2.30 2003/03/24 12:58:56 hal9
9155 Add new section on Predefined Filters.
9157 Revision 1.123.2.29 2003/03/20 02:45:29 hal9
9158 More problems with \-\-chroot causing markup problems :(
9160 Revision 1.123.2.28 2003/03/19 00:35:24 hal9
9161 Manual edit of revision log because 'chroot' (even inside a comment) was
9162 causing Docbook to hang here (due to double hyphen and the processor thinking
9165 Revision 1.123.2.27 2003/03/18 19:37:14 oes
9166 s/Advanced|Radical/Adventuresome/g to avoid complaints re fun filter
9168 Revision 1.123.2.26 2003/03/17 16:50:53 oes
9169 Added documentation for new chroot option
9171 Revision 1.123.2.25 2003/03/15 18:36:55 oes
9172 Adapted to the new filters
9174 Revision 1.123.2.24 2002/11/17 06:41:06 hal9
9175 Move default profiles table from FAQ to U-M, and other minor related changes.
9178 Revision 1.123.2.23 2002/10/21 02:32:01 hal9
9179 Updates to the user.action examples section. A few new ones.
9181 Revision 1.123.2.22 2002/10/12 00:51:53 hal9
9182 Add demoronizer to filter section.
9184 Revision 1.123.2.21 2002/10/10 04:09:35 hal9
9185 s/Advanced/Radical/ and added very brief note.
9187 Revision 1.123.2.20 2002/10/10 03:49:21 hal9
9188 Add notes to session-cookies-only and Quickstart about pre-existing
9189 cookies. Also, note content-cookies work differently.
9191 Revision 1.123.2.19 2002/09/26 01:25:36 hal9
9192 More explanation on Privoxy patterns, more on content-cookies and SSL.
9194 Revision 1.123.2.18 2002/08/22 23:47:58 hal9
9195 Add 'Documentation' to Privoxy Menu shot in Configuration section to match
9198 Revision 1.123.2.17 2002/08/18 01:13:05 hal9
9199 Spell checked (only one typo this time!).
9201 Revision 1.123.2.16 2002/08/09 19:20:54 david__schmidt
9202 Update to Mac OS X startup script name
9204 Revision 1.123.2.15 2002/08/07 17:32:11 oes
9205 Converted some internal links from ulink to link for PDF creation; no content changed
9207 Revision 1.123.2.14 2002/08/06 09:16:13 oes
9208 Nits re: actions file download
9210 Revision 1.123.2.13 2002/08/02 18:23:19 g_sauthoff
9211 Just 2 small corrections to the Gentoo sections
9213 Revision 1.123.2.12 2002/08/02 18:17:21 g_sauthoff
9214 Added 2 Gentoo sections
9216 Revision 1.123.2.11 2002/07/26 15:20:31 oes
9217 - Added version info to title
9218 - Added info on new filters
9219 - Revised parts of the filter file tutorial
9220 - Added info on where to get updated actions files
9222 Revision 1.123.2.10 2002/07/25 21:42:29 hal9
9223 Add brief notes on not proxying non-HTTP protocols.
9225 Revision 1.123.2.9 2002/07/11 03:40:28 david__schmidt
9227 Updated Mac OS X sections due to installation location change
9229 Revision 1.123.2.8 2002/06/09 16:36:32 hal9
9230 Clarifications on filtering and MIME. Hardcode 'latest release' in index.html.
9232 Revision 1.123.2.7 2002/06/09 00:29:34 hal9
9233 Touch ups on filtering, in actions section and Anatomy.
9235 Revision 1.123.2.6 2002/06/06 23:11:03 hal9
9236 Fix broken link. Linkchecked all docs.
9238 Revision 1.123.2.5 2002/05/29 02:01:02 hal9
9239 This is break out of the entire config section from u-m, so it can
9240 eventually be used to generate the comments, etc in the main config file
9241 so that these are in sync with each other.
9243 Revision 1.123.2.4 2002/05/27 03:28:45 hal9
9244 Ooops missed something from David.
9246 Revision 1.123.2.3 2002/05/27 03:23:17 hal9
9247 Fix FIXMEs for OS2 and Mac OS X startup. Fix Redhat typos (should be Red Hat).
9248 That's a wrap, I think.
9250 Revision 1.123.2.2 2002/05/26 19:02:09 hal9
9251 Move Amiga stuff around to take of FIXME in start up section.
9253 Revision 1.123.2.1 2002/05/26 17:04:25 hal9
9254 -Spellcheck, very minor edits, and sync across branches
9256 Revision 1.123 2002/05/24 23:19:23 hal9
9257 Include new image (Proxy setup). More fun with guibutton.
9258 Minor corrections/clarifications here and there.
9260 Revision 1.122 2002/05/24 13:24:08 oes
9261 Added Bookmarklet for one-click pre-filled access to show-url-info
9263 Revision 1.121 2002/05/23 23:20:17 oes
9264 - Changed more (all?) references to actions to the
9265 <literal><link> style.
9266 - Small fixes in the actions chapter
9267 - Small clarifications in the quickstart to ad blocking
9268 - Removed <emphasis> from <title>s since the new doc CSS
9269 renders them red (bad in TOC).
9271 Revision 1.120 2002/05/23 19:16:43 roro
9272 Correct Debian specials (installation and startup).
9274 Revision 1.119 2002/05/22 17:17:05 oes
9277 Revision 1.118 2002/05/21 04:54:55 hal9
9278 -New Section: Quickstart to Ad Blocking
9279 -Reformat Actions Anatomy to match new CGI layout
9281 Revision 1.117 2002/05/17 13:56:16 oes
9282 - Reworked & extended Templates chapter
9283 - Small changes to Regex appendix
9284 - #included authors.sgml into (C) and hist chapter
9286 Revision 1.116 2002/05/17 03:23:46 hal9
9287 Fixing merge conflict in Quickstart section.
9289 Revision 1.115 2002/05/16 16:25:00 oes
9290 Extended the Filter File chapter & minor fixes
9292 Revision 1.114 2002/05/16 09:42:50 oes
9293 More ulink->link, added some hints to Quickstart section
9295 Revision 1.113 2002/05/15 21:07:25 oes
9296 Extended and further commented the example actions files
9298 Revision 1.112 2002/05/15 03:57:14 hal9
9299 Spell check. A few minor edits here and there for better syntax and
9302 Revision 1.111 2002/05/14 23:01:36 oes
9305 Revision 1.110 2002/05/14 19:10:45 oes
9306 Restored alphabetical order of actions
9308 Revision 1.109 2002/05/14 17:23:11 oes
9309 Renamed the prevent-*-cookies actions, extended aliases section and moved it before the example AFs
9311 Revision 1.108 2002/05/14 15:29:12 oes
9312 Completed proofreading the actions chapter
9314 Revision 1.107 2002/05/12 03:20:41 hal9
9315 Small clarifications for 127.0.0.1 vs localhost for listen-address since this
9316 apparently an important distinction for some OS's.
9318 Revision 1.106 2002/05/10 01:48:20 hal9
9319 This is mostly proposed copyright/licensing additions and changes. Docs
9320 are still GPL, but licensing and copyright are more visible. Also, copyright
9321 changed in doc header comments (eliminate references to JB except FAQ).
9323 Revision 1.105 2002/05/05 20:26:02 hal9
9324 Sorting out license vs copyright in these docs.
9326 Revision 1.104 2002/05/04 08:44:45 swa
9329 Revision 1.103 2002/05/04 00:40:53 hal9
9330 -Remove the TOC first page kludge. It's fixed proper now in ldp.dsl.in.
9331 -Some minor additions to Quickstart.
9333 Revision 1.102 2002/05/03 17:46:00 oes
9334 Further proofread & reactivated short build instructions
9336 Revision 1.101 2002/05/03 03:58:30 hal9
9337 Move the user-manual config directive to top of section. Add note about
9338 Privoxy needing read permissions for configs, and write for logs.
9340 Revision 1.100 2002/04/29 03:05:55 hal9
9341 Add clarification on differences of new actions files.
9343 Revision 1.99 2002/04/28 16:59:05 swa
9344 more structure in starting section
9346 Revision 1.98 2002/04/28 05:43:59 hal9
9347 This is the break up of configuration.html into multiple files. This
9348 will probably break links elsewhere :(
9350 Revision 1.97 2002/04/27 21:04:42 hal9
9351 -Rewrite of Actions File example.
9352 -Add section for user-manual directive in config.
9354 Revision 1.96 2002/04/27 05:32:00 hal9
9355 -Add short section to Filter Files to tie in with +filter action.
9356 -Start rewrite of examples in Actions Examples (not finished).
9358 Revision 1.95 2002/04/26 17:23:29 swa
9359 bookmarks cleaned, changed structure of user manual, screen and programlisting cleanups, and numerous other changes that I forgot
9361 Revision 1.94 2002/04/26 05:24:36 hal9
9362 -Add most of Andreas suggestions to Chain of Events section.
9363 -A few other minor corrections and touch up.
9365 Revision 1.92 2002/04/25 18:55:13 hal9
9366 More catchups on new actions files, and new actions names.
9367 Other assorted cleanups, and minor modifications.
9369 Revision 1.91 2002/04/24 02:39:31 hal9
9370 Add 'Chain of Events' section.
9372 Revision 1.90 2002/04/23 21:41:25 hal9
9373 Linuxconf is deprecated on RH, substitute chkconfig.
9375 Revision 1.89 2002/04/23 21:05:28 oes
9376 Added hint for startup on Red Hat
9378 Revision 1.88 2002/04/23 05:37:54 hal9
9379 Add AmigaOS install stuff.
9381 Revision 1.87 2002/04/23 02:53:15 david__schmidt
9382 Updated Mac OS X installation section
9383 Added a few English tweaks here an there
9385 Revision 1.86 2002/04/21 01:46:32 hal9
9386 Re-write actions section.
9388 Revision 1.85 2002/04/18 21:23:23 hal9
9389 Fix ugly typo (mine).
9391 Revision 1.84 2002/04/18 21:17:13 hal9
9392 Spell Redhat correctly (ie Red Hat). A few minor grammar corrections.
9394 Revision 1.83 2002/04/18 18:21:12 oes
9395 Added RPM install detail
9397 Revision 1.82 2002/04/18 12:04:50 oes
9400 Revision 1.81 2002/04/18 11:50:24 oes
9401 Extended Install section - needs fixing by packagers
9403 Revision 1.80 2002/04/18 10:45:19 oes
9404 Moved text to buildsource.sgml, renamed some filters, details
9406 Revision 1.79 2002/04/18 03:18:06 hal9
9407 Spellcheck, and minor touchups.
9409 Revision 1.78 2002/04/17 18:04:16 oes
9412 Revision 1.77 2002/04/17 13:51:23 oes
9413 Proofreading, part one
9415 Revision 1.76 2002/04/16 04:25:51 hal9
9416 -Added 'Note to Upgraders' and re-ordered the 'Quickstart' section.
9417 -Note about proxy may need requests to re-read config files.
9419 Revision 1.75 2002/04/12 02:08:48 david__schmidt
9420 Remove OS/2 building info... it is already in the developer-manual
9422 Revision 1.74 2002/04/11 00:54:38 hal9
9423 Add small section on submitting actions.
9425 Revision 1.73 2002/04/10 18:45:15 swa
9428 Revision 1.72 2002/04/10 04:06:19 hal9
9429 Added actions feedback to Bookmarklets section
9431 Revision 1.71 2002/04/08 22:59:26 hal9
9432 Version update. Spell chkconfig correctly :)
9434 Revision 1.70 2002/04/08 20:53:56 swa
9437 Revision 1.69 2002/04/06 05:07:29 hal9
9438 -Add privoxy-man-page.sgml, for man page.
9439 -Add authors.sgml for AUTHORS (and p-authors.sgml)
9440 -Reworked various aspects of various docs.
9441 -Added additional comments to sub-docs.
9443 Revision 1.68 2002/04/04 18:46:47 swa
9444 consistent look. reuse of copyright, history et. al.
9446 Revision 1.67 2002/04/04 17:27:57 swa
9447 more single file to be included at multiple points. make maintaining easier
9449 Revision 1.66 2002/04/04 06:48:37 hal9
9450 Structural changes to allow for conditional inclusion/exclusion of content
9451 based on entity toggles, e.g. 'entity % p-not-stable "INCLUDE"'. And
9452 definition of internal entities, e.g. 'entity p-version "2.9.13"' that will
9453 eventually be set by Makefile.
9454 More boilerplate text for use across multiple docs.
9456 Revision 1.65 2002/04/03 19:52:07 swa
9457 enhance squid section due to user suggestion
9459 Revision 1.64 2002/04/03 03:53:43 hal9
9460 A few minor bug fixes, and touch ups. Ready for review.
9462 Revision 1.63 2002/04/01 16:24:49 hal9
9463 Define entities to include boilerplate text. See doc/source/*.
9465 Revision 1.62 2002/03/30 04:15:53 hal9
9466 - Fix privoxy.org/config links.
9467 - Paste in Bookmarklets from Toggle page.
9468 - Move Quickstart nearer top, and minor rework.
9470 Revision 1.61 2002/03/29 01:31:08 hal9
9473 Revision 1.60 2002/03/27 01:57:34 hal9
9474 Added more to Anatomy section.
9476 Revision 1.59 2002/03/27 00:54:33 hal9
9477 Touch up intro for new name.
9479 Revision 1.58 2002/03/26 22:29:55 swa
9480 we have a new homepage!
9482 Revision 1.57 2002/03/24 20:33:30 hal9
9483 A few minor catch ups with name change.
9485 Revision 1.56 2002/03/24 16:17:06 swa
9486 configure needs to be generated.
9488 Revision 1.55 2002/03/24 16:08:08 swa
9489 we are too lazy to make a block-built
9490 privoxy logo. hence removed the option.
9492 Revision 1.54 2002/03/24 15:46:20 swa
9493 name change related issue.
9495 Revision 1.53 2002/03/24 11:51:00 swa
9496 name change. changed filenames.
9498 Revision 1.52 2002/03/24 11:01:06 swa
9501 Revision 1.51 2002/03/23 15:13:11 swa
9502 renamed every reference to the old name with foobar.
9503 fixed "application foobar application" tag, fixed
9504 "the foobar" with "foobar". left junkbustser in cvs
9505 comments and remarks to history untouched.
9507 Revision 1.50 2002/03/23 05:06:21 hal9
9510 Revision 1.49 2002/03/21 17:01:05 hal9
9511 New section in Appendix.
9513 Revision 1.48 2002/03/12 06:33:01 hal9
9514 Catching up to Andreas and re_filterfile changes.
9516 Revision 1.47 2002/03/11 13:13:27 swa
9517 correct feedback channels
9519 Revision 1.46 2002/03/10 00:51:08 hal9
9520 Added section on JB internal pages in Appendix.
9522 Revision 1.45 2002/03/09 17:43:53 swa
9525 Revision 1.44 2002/03/09 17:08:48 hal9
9526 New section on Jon's actions file editor, and move some stuff around.
9528 Revision 1.43 2002/03/08 00:47:32 hal9
9529 Added imageblock{pattern}.
9531 Revision 1.42 2002/03/07 18:16:55 swa
9534 Revision 1.41 2002/03/07 16:46:43 hal9
9535 Fix a few markup problems for jade.
9537 Revision 1.40 2002/03/07 16:28:39 swa
9538 provide correct feedback channels
9540 Revision 1.39 2002/03/06 16:19:28 hal9
9541 Note on perceived filtering slowdown per FR.
9543 Revision 1.38 2002/03/05 23:55:14 hal9
9544 Stupid I did it again. Double hyphen in comment breaks jade.
9546 Revision 1.37 2002/03/05 23:53:49 hal9
9547 jade barfs on '- -' embedded in comments. - -user option broke it.
9549 Revision 1.36 2002/03/05 22:53:28 hal9
9550 Add new - - user option.
9552 Revision 1.35 2002/03/05 00:17:27 hal9
9553 Added section on command line options.
9555 Revision 1.34 2002/03/04 19:32:07 oes
9556 Changed default port to 8118
9558 Revision 1.33 2002/03/03 19:46:13 hal9
9559 Emphasis on where/how to report bugs, etc
9561 Revision 1.32 2002/03/03 09:26:06 joergs
9562 AmigaOS changes, config is now loaded from PROGDIR: instead of
9563 AmiTCP:db/junkbuster/ if no configuration file is specified on the
9566 Revision 1.31 2002/03/02 22:45:52 david__schmidt
9569 Revision 1.30 2002/03/02 22:00:14 hal9
9570 Updated 'New Features' list. Ran through spell-checker.
9572 Revision 1.29 2002/03/02 20:34:07 david__schmidt
9573 Update OS/2 build section
9575 Revision 1.28 2002/02/24 14:34:24 jongfoster
9576 Formatting changes. Now changing the doctype to DocBook XML 4.1
9577 will work - no other changes are needed.
9579 Revision 1.27 2002/01/11 14:14:32 hal9
9580 Added a very short section on Templates
9582 Revision 1.26 2002/01/09 20:02:50 hal9
9583 Fix bug re: auto-detect config file changes.
9585 Revision 1.25 2002/01/09 18:20:30 hal9
9586 Touch ups for *.action files.
9588 Revision 1.24 2001/12/02 01:13:42 hal9
9591 Revision 1.23 2001/12/02 00:20:41 hal9
9592 Updates for recent changes.
9594 Revision 1.22 2001/11/05 23:57:51 hal9
9595 Minor update for startup now daemon mode.
9597 Revision 1.21 2001/10/31 21:11:03 hal9
9598 Correct 2 minor errors
9600 Revision 1.18 2001/10/24 18:45:26 hal9
9601 *** empty log message ***
9603 Revision 1.17 2001/10/24 17:10:55 hal9
9604 Catching up with Jon's recent work, and a few other things.
9606 Revision 1.16 2001/10/21 17:19:21 swa
9607 wrong url in documentation
9609 Revision 1.15 2001/10/14 23:46:24 hal9
9610 Various minor changes. Fleshed out SEE ALSO section.
9612 Revision 1.13 2001/10/10 17:28:33 hal9
9615 Revision 1.12 2001/09/28 02:57:04 hal9
9618 Revision 1.11 2001/09/28 02:25:20 hal9
9621 Revision 1.9 2001/09/27 23:50:29 hal9
9622 A few changes. A short section on regular expression in appendix.
9624 Revision 1.8 2001/09/25 00:34:59 hal9
9625 Some additions, and re-arranging.
9627 Revision 1.7 2001/09/24 14:31:36 hal9
9630 Revision 1.6 2001/09/24 14:10:32 hal9
9631 Including David's OS/2 installation instructions.
9633 Revision 1.2 2001/09/13 15:27:40 swa
9636 Revision 1.1 2001/09/12 15:36:41 swa
9637 source files for junkbuster documentation
9639 Revision 1.3 2001/09/10 17:43:59 swa
9640 first proposal of a structure.
9642 Revision 1.2 2001/06/13 14:28:31 swa
9643 docs should have an author.
9645 Revision 1.1 2001/06/13 14:20:37 swa
9646 first import of project's documentation for the webserver.