1 Privoxy 3.0.5 User Manual
3 Copyright © 2001 - 2006 by Privoxy Developers
5 $Id: user-manual.sgml,v 2.22 2006/09/22 01:27:55 hal9 Exp $
7 The Privoxy User Manual gives users information on how to install, configure
10 Privoxy is a web proxy with advanced filtering capabilities for protecting
11 privacy, modifying web page data, managing cookies, controlling access, and
12 removing ads, banners, pop-ups and other obnoxious Internet junk. Privoxy has a
13 very flexible configuration and can be customized to suit individual needs and
14 tastes. Privoxy has application for both stand-alone systems and multi-user
17 Privoxy is based on Internet Junkbuster (tm).
19 You can find the latest version of the Privoxy User Manual at http://
20 www.privoxy.org/user-manual/. Please see the Contact section on how to contact
23 -------------------------------------------------------------------------------
34 2.1.1. Red Hat, SuSE and Conectiva RPMs
37 2.1.4. Solaris, NetBSD, FreeBSD, HP-UX
43 2.2. Building from Source
44 2.3. Keeping your Installation Up-to-Date
46 3. What's New in this Release
48 3.1. Note to Upgraders
50 4. Quickstart to Using Privoxy
52 4.1. Quickstart to Ad Blocking
56 5.1. Red Hat, Fedora and Conectiva
60 5.5. Solaris, NetBSD, FreeBSD, HP-UX and others
65 5.10. Command Line Options
67 6. Privoxy Configuration
69 6.1. Controlling Privoxy with Your Web Browser
70 6.2. Configuration Files Overview
72 7. The Main Configuration File
74 7.1. Local Set-up Documentation
81 7.2. Configuration and Log File Locations
94 7.3.2. single-threaded
96 7.4. Access Control and Security
100 7.4.3. enable-remote-toggle
101 7.4.4. enable-remote-http-toggle
102 7.4.5. enable-edit-actions
103 7.4.6. ACLs: permit-access and deny-access
109 7.5.2. forward-socks4 and forward-socks4a
110 7.5.3. Advanced Forwarding Examples
111 7.5.4. forwarded-connect-retries
113 7.6. Windows GUI Options
117 8.1. Finding the Right Mix
119 8.3. How Actions are Applied to URLs
122 8.4.1. The Domain Pattern
123 8.4.2. The Path Pattern
129 8.5.3. content-type-overwrite
130 8.5.4. crunch-client-header
131 8.5.5. crunch-if-none-match
132 8.5.6. crunch-incoming-cookies
133 8.5.7. crunch-server-header
134 8.5.8. crunch-outgoing-cookies
135 8.5.9. deanimate-gifs
136 8.5.10. downgrade-http-version
137 8.5.11. fast-redirects
139 8.5.13. filter-client-headers
140 8.5.14. filter-server-headers
141 8.5.15. force-text-mode
142 8.5.16. handle-as-empty-document
143 8.5.17. handle-as-image
144 8.5.18. hide-accept-language
145 8.5.19. hide-content-disposition
146 8.5.20. hide-if-modified-since
147 8.5.21. hide-forwarded-for-headers
148 8.5.22. hide-from-header
149 8.5.23. hide-referrer
150 8.5.24. hide-user-agent
151 8.5.25. inspect-jpegs
153 8.5.27. limit-connect
154 8.5.28. prevent-compression
155 8.5.29. overwrite-last-modified
157 8.5.31. send-vanilla-wafer
159 8.5.33. session-cookies-only
160 8.5.34. set-image-blocker
161 8.5.35. treat-forbidden-connects-like-blocks
165 8.7. Actions Files Tutorial
167 8.7.1. default.action
172 9.1. Filter File Tutorial
173 9.2. The Pre-defined Filters
175 10. Privoxy's Template Files
176 11. Contacting the Developers, Bug Reporting and Feature Requests
179 11.2. Reporting Problems
181 11.2.1. Reporting Ads or Other Configuration Problems
182 11.2.2. Reporting Bugs
184 11.3. Request New Features
187 12. Privoxy Copyright, License and History
196 14.1. Regular Expressions
197 14.2. Privoxy's Internal Pages
201 14.3. Chain of Events
202 14.4. Troubleshooting: Anatomy of an Action
206 This documentation is included with the current BETA version of Privoxy,
207 v.3.0.5, and is mostly complete at this point. The most up to date reference
208 for the time being is still the comments in the source files and in the
209 individual configuration files. Development of a new version is currently
210 nearing completion, and includes significant changes and enhancements over
213 Since this is a BETA version, not all new features are well tested. This
214 documentation may be slightly out of sync as a result (especially with CVS
215 sources). And there may be bugs, though hopefully not many!
217 -------------------------------------------------------------------------------
221 In addition to the core features of ad blocking and cookie management, Privoxy
222 provides many supplemental features, some of them currently under development,
223 that give the end-user more control, more privacy and more freedom:
225 * Integrated browser based configuration and control utility at http://
226 config.privoxy.org/ (shortcut: http://p.p/). Browser-based tracing of rule
227 and filter effects. Remote toggling.
229 * Web page content filtering (removes banners based on size, invisible
230 "web-bugs", JavaScript and HTML annoyances, pop-up windows, etc.)
232 * Modularized configuration that allows for standard settings and user
233 settings to reside in separate files, so that installing updated actions
234 files won't overwrite individual user settings.
236 * HTTP/1.1 compliant (but not all optional 1.1 features are supported).
238 * Support for Perl Compatible Regular Expressions in the configuration files,
239 and generally a more sophisticated and flexible configuration syntax over
242 * Improved cookie management features (e.g. session based cookies).
246 * Bypass many click-tracking scripts (avoids script redirection).
248 * Multi-threaded (POSIX and native threads).
250 * User-customizable HTML templates for all proxy-generated pages (e.g.
253 * Auto-detection and re-reading of config file changes.
255 * Improved signal handling, and a true daemon mode (Unix).
257 * Every feature now controllable on a per-site or per-location basis,
258 configuration more powerful and versatile over-all.
260 * Many smaller new features added, limitations and bugs removed, and security
263 -------------------------------------------------------------------------------
267 Privoxy is available both in convenient pre-compiled packages for a wide range
268 of operating systems, and as raw source code. For most users, we recommend
269 using the packages, which can be downloaded from our Privoxy Project Page.
271 Note: On some platforms, the installer may remove previously installed
272 versions, if found. (See below for your platform). In any case be sure to
273 backup your old configuration if it is valuable to you. See the note to
274 upgraders section below.
276 -------------------------------------------------------------------------------
280 How to install the binary packages depends on your operating system:
282 -------------------------------------------------------------------------------
284 2.1.1. Red Hat, SuSE and Conectiva RPMs
286 RPMs can be installed with rpm -Uvh privoxy-3.0.5-1.rpm, and will use /etc/
287 privoxy for the location of configuration files.
289 Note that on Red Hat, Privoxy will not be automatically started on system boot.
290 You will need to enable that using chkconfig, ntsysv, or similar methods.
292 If you have problems with failed dependencies, try rebuilding the SRC RPM: rpm
293 --rebuild privoxy-3.0.5-1.src.rpm. This will use your locally installed
294 libraries and RPM version.
296 Also note that if you have a Junkbuster RPM installed on your system, you need
297 to remove it first, because the packages conflict. Otherwise, RPM will try to
298 remove Junkbuster automatically if found, before installing Privoxy.
300 -------------------------------------------------------------------------------
304 DEBs can be installed with apt-get install privoxy, and will use /etc/privoxy
305 for the location of configuration files.
307 -------------------------------------------------------------------------------
311 Just double-click the installer, which will guide you through the installation
312 process. You will find the configuration files in the same directory as you
313 installed Privoxy in.
315 Version 3.0.4 introduced full Windows service functionality. On Windows only,
316 the Privoxy program has two new command line arguments to install and uninstall
317 Privoxy as a service.
321 --install[:service_name]
323 --uninstall[:service_name]
325 After invoking Privoxy with --install, you will need to bring up the Windows
326 service console to assign the user you want Privoxy to run under, and whether
327 or not you want it to run whenever the system starts. You can start the Windows
328 services console with the following command: services.msc. If you do not take
329 the manual step of modifying Privoxy's service settings, it will not start.
330 Note too that you will need to give Privoxy a user account that actually
331 exists, or it will not be permitted to write to its log and configuration
334 -------------------------------------------------------------------------------
336 2.1.4. Solaris, NetBSD, FreeBSD, HP-UX
338 Create a new directory, cd to it, then unzip and untar the archive. For the
339 most part, you'll have to figure out where things go.
341 -------------------------------------------------------------------------------
345 First, make sure that no previous installations of Junkbuster and / or Privoxy
346 are left on your system. Check that no Junkbuster or Privoxy objects are in
349 Then, just double-click the WarpIN self-installing archive, which will guide
350 you through the installation process. A shadow of the Privoxy executable will
351 be placed in your startup folder so it will start automatically whenever OS/2
354 The directory you choose to install Privoxy into will contain all of the
357 -------------------------------------------------------------------------------
361 Unzip the downloaded file (you can either double-click on the file from the
362 finder, or from the desktop if you downloaded it there). Then, double-click on
363 the package installer icon named Privoxy.pkg and follow the installation
364 process. Privoxy will be installed in the folder /Library/Privoxy. It will
365 start automatically whenever you start up. To prevent it from starting
366 automatically, remove or rename the folder /Library/StartupItems/Privoxy.
368 To start Privoxy by hand, double-click on StartPrivoxy.command in the /Library/
369 Privoxy folder. Or, type this command in the Terminal:
371 /Library/Privoxy/StartPrivoxy.command
374 You will be prompted for the administrator password.
376 -------------------------------------------------------------------------------
380 Copy and then unpack the lha archive to a suitable location. All necessary
381 files will be installed into Privoxy directory, including all configuration and
382 log files. To uninstall, just remove this directory.
384 -------------------------------------------------------------------------------
388 Gentoo source packages (Ebuilds) for Privoxy are contained in the Gentoo
389 Portage Tree (they are not on the download page, but there is a Gentoo section,
390 where you can see when a new Privoxy Version is added to the Portage Tree).
392 Before installing Privoxy under Gentoo just do first emerge rsync to get the
393 latest changes from the Portage tree. With emerge privoxy you install the
396 Configuration files are in /etc/privoxy, the documentation is in /usr/share/doc
397 /privoxy-3.0.5 and the Log directory is in /var/log/privoxy.
399 -------------------------------------------------------------------------------
401 2.2. Building from Source
403 The most convenient way to obtain the Privoxy sources is to download the source
404 tarball from our project page.
406 If you like to live on the bleeding edge and are not afraid of using possibly
407 unstable development versions, you can check out the up-to-the-minute version
408 directly from the CVS repository.
410 To build Privoxy from source, autoconf, GNU make (gmake), and, of course, a C
411 compiler like gcc are required.
413 When building from a source tarball, first unpack the source:
415 tar xzvf privoxy-3.0.5-beta-src* [.tgz or .tar.gz]
416 cd privoxy-3.0.5-beta
418 For retrieving the current CVS sources, you'll need a CVS client installed.
419 Note that sources from CVS are typicially development quality, and may not be
420 stable, or well tested. To download CVS source, check the Sourceforge
421 documentation, which might give commands like:
423 cvs -d:pserver:anonymous@ijbswa.cvs.sourceforge.net:/cvsroot/ijbswa login
424 cvs -z3 -d:pserver:anonymous@ijbswa.cvs.sourceforge.net:/cvsroot/ijbswa co current
427 This will create a directory named current/, which will contain the source
430 You can also check out any Privoxy "branch", just exchange the current name
431 with the wanted branch name (Example: v_3_0_branch for the 3.0 cvs tree).
433 It is also strongly recommended to not run Privoxy as root, and instead it is
434 suggested to create a "privoxy" user and group for this purpose. See your local
435 documentation for the correct command line to do this.
437 /etc/passwd might then look like:
439 privoxy:*:7777:7777:privoxy proxy:/no/home:/no/shell
441 And then /etc/group, like:
445 Some binary packages may do this for you.
447 Then, to build from either unpacked tarball or CVS source:
451 ./configure # (--help to see options)
452 make # (the make from GNU, sometimes called gmake)
454 make -n install # (to see where all the files will go)
455 make -s install # (to really install, -s to silence output)
457 If you have GNU make, you can have the first four steps automatically done for
462 in the freshly downloaded or unpacked source directory.
464 WARNING: If installing as root, the install will fail unless a non-root user or
465 group is specified, or a privoxy user and group already exist on the system. If
466 a non-root user is specified, and no group, then the installation will try to
467 also use a group of the same name as "user". If a group is specified (and no
468 user), then the support files will be installed as writable by that group, and
469 owned by the user running the installation.
471 configure accepts --with-user and --with-group options for setting user and
472 group ownership of the configuration files (which need to be writable by the
473 daemon). The specified user must already exist. When starting Privoxy, it
474 should be run as this same user to insure write access to configuration and log
477 Alternately, you can specify user and group on the make command line, but be
478 sure both already exist:
480 make -s install USER=privoxy GROUP=privoxy
482 The default installation path for make install is /usr/local. This may of
483 course be customized with the various ./configure path options. If you are
484 doing a root install to anywhere else besides /usr/local, be sure to set the
485 appropriate paths with the correct configure options (./configure --help).
487 If you do install to /usr/local, the install will use sysconfdir=$prefix/etc/
488 privoxy by default. All other destinations, and the direct usage of
489 --sysconfdir flag behave like normal, i.e. will not add the extra privoxy
490 directory. This is for a safer install, as there may already exist another
491 program that uses a file with the "config" name, and thus makes /usr/local/etc
494 If installing to /usr/local, the docs will go by default to $prefix/share/doc.
495 But if this directory doesn't exist, it will then try $prefix/doc and install
496 there before creating a new $prefix/share/doc just for Privoxy.
498 Again, if the installs goes to /usr/local, the localstatedir (ie: var/) will
499 default to /var instead of $prefix/var so the logs will go to /var/log/privoxy
500 /, and the pid file will be created in /var/run/privoxy.pid.
502 make install will attempt to set the correct values in config (main
503 configuration file). You may want to check this to make sure all values are
504 correct. If appropriate, an init script will be installed, but it is up to the
505 user to determine how and where to start Privoxy. The init script should be
506 checked for correct paths and values, if anything other than a default install
509 If install finds previous versions of any local configuration files, these will
510 not be overwritten, and the new ones will be installed with a "new" extension.
511 default.action, default.filter, and standard.action will be overwritten. You
512 will then need to manually update the other installed configuration files as
513 needed. All template files will be overwritten. If you have customized, local
514 templates, you should save these first. If a previous version of Privoxy is
515 already running, you will have to restart it manually.
517 For more detailed instructions on how to build Redhat RPMs, Windows
518 self-extracting installers, building on platforms with special requirements
519 etc, please consult the developer manual.
521 -------------------------------------------------------------------------------
523 2.3. Keeping your Installation Up-to-Date
525 As user feedback comes in and development continues, we will make updated
526 versions of both the main actions file (as a separate package) and the software
527 itself (including the actions file) available for download.
529 If you wish to receive an email notification whenever we release updates of
530 Privoxy or the actions file, subscribe to our announce mailing list,
531 ijbswa-announce@lists.sourceforge.net.
533 In order not to lose your personal changes and adjustments when updating to the
534 latest default.action file we strongly recommend that you use user.action and
535 user.filter for your local customizations of Privoxy. See the Chapter on
536 actions files for details.
538 -------------------------------------------------------------------------------
540 3. What's New in this Release
542 There are many improvements and new features in Privoxy 3.0.5 :
544 * Multiple filter files can now be specified in config. This allows for
545 locally defined filters that can be maintained separately from the filters
546 as supplied by the developers, i.e. default.filter.
548 * There are a number of new actions:
550 + content-type-overwrite
552 + crunch-client-header
554 + crunch-if-none-match
556 + crunch-server-header
558 + filter-client-headers
560 + filter-server-headers
564 + handle-as-empty-document
566 + hide-accept-language
568 + hide-content-disposition
570 + hide-if-modified-since
574 + overwrite-last-modified
578 + treat-forbidden-connects-like-blocks
580 In addition, fast-redirects has been significantly improved with enhanced
583 And hide-referrer has a new option, conditional block.
585 * MS-Windows versions can now be installed and started as a Windows service.
587 * config has two new options: enable-remote-http-toggle, and
588 forwarded-connect-retries.
590 And there is improved handling of the user-manual option, for placing
591 documentation and help files on the local system.
593 * Actions files problems and suggestions are now being directed to: http://
594 sourceforge.net/tracker/?group_id=11118&atid=460288. Please use this to
595 report such configuration related problems as missed ads, sites that don't
596 function properly due to one action or another, innocent images being
599 * In addition, there are numerous bug fixes and significant enhancements,
600 including error pages should no longer be cached if the problem is fixed,
601 much better DNS error handling, and various logging improvements.
603 * The default actions setting is now Cautious. Previous releases had a
604 default setting of Medium. Experienced users may want to adjust this, as it
605 is fairly conservative by Privoxy standards and past practices. See http://
606 config.privoxy.org/edit-actions-list?f=default. New users should try the
607 default settings for a while before turning up the volume.
609 -------------------------------------------------------------------------------
611 3.1. Note to Upgraders
613 A quick list of things to be aware of before upgrading from earlier versions of
616 * Some installers may remove earlier versions completely, including
617 configuration files. Save any important configuration files!
619 * On the other hand, other installers may not overwrite any existing
620 configuration files, thinking you will want to do that. You may want to
621 manually check your saved files against the newer versions to see if the
622 improvements have merit, or whether there are new options that you may want
623 to consider. There are a number of new features, but most won't be
624 available unless these features are incorporated into your configuration
627 * See the full documentation on fast-redirects which has changed syntax, and
628 will require adjustments to local configs, such as user.action. You must
629 reference the new syntax:
631 { +fast-redirects{check-decoded-url} }
636 * The jarfile, cookie logger, is off by default now.
638 * What constitutes a "default" configuration has changed, and you may want to
639 review which actions are "on" by default. This is primarily a matter of
640 emphasis, but some features you may have been used to, may now be "off" by
641 default. There are also a number of new actions you may want to consider,
642 most of which are not incorporated into the default settings as yet (see
645 * Some installers may not automatically start Privoxy after installation.
647 -------------------------------------------------------------------------------
649 4. Quickstart to Using Privoxy
651 * Install Privoxy. See the Installation Section below for platform specific
654 * Advanced users and those who want to offer Privoxy service to more than
655 just their local machine should check the main config file, especially the
656 security-relevant options. These are off by default.
658 * Start Privoxy, if the installation program has not done this already (may
659 vary according to platform). See the section Starting Privoxy.
661 * Set your browser to use Privoxy as HTTP and HTTPS (SSL) proxy by setting
662 the proxy configuration for address of 127.0.0.1 and port 8118. DO NOT
663 activate proxying for FTP or any protocols besides HTTP and HTTPS (SSL)! It
666 * Flush your browser's disk and memory caches, to remove any cached ad
667 images. If using Privoxy to manage cookies, you should remove any currently
670 * A default installation should provide a reasonable starting point for most.
671 There will undoubtedly be occasions where you will want to adjust the
672 configuration, but that can be dealt with as the need arises. Little to no
673 initial configuration is required in most cases.
675 See the Configuration section for more configuration options, and how to
676 customize your installation. You might also want to look at the next
677 section for a quick introduction to how Privoxy blocks ads and banners.
679 * If you experience ads that slip through, innocent images that are blocked,
680 or otherwise feel the need to fine-tune Privoxy's behavior, take a look at
681 the actions files. As a quick start, you might find the richly commented
682 examples helpful. You can also view and edit the actions files through the
683 web-based user interface. The Appendix "Troubleshooting: Anatomy of an
684 Action" has hints how to understand and debug actions that "misbehave".
686 * For easy access to Privoxy's most important controls, drag the provided
687 Bookmarklets into your browser's personal toolbar.
689 * Please see the section Contacting the Developers on how to report bugs,
690 problems with websites or to get help.
692 * Now enjoy surfing with enhanced control, comfort and privacy!
694 -------------------------------------------------------------------------------
696 4.1. Quickstart to Ad Blocking
698 Ad blocking is but one of Privoxy's array of features. Many of these features
699 are for the technically minded advanced user. But, ad and banner blocking is
700 surely common ground for everybody.
702 This section will provide a quick summary of ad blocking so you can get up to
703 speed quickly without having to read the more extensive information provided
704 below, though this is highly recommended.
706 First a bit of a warning ... blocking ads is much like blocking SPAM: the more
707 aggressive you are about it, the more likely you are to block things that were
708 not intended. So there is a trade off here. If you want extreme ad free
709 browsing, be prepared to deal with more "problem" sites, and to spend more time
710 adjusting the configuration to solve these unintended consequences. In short,
711 there is not an easy way to eliminate all ads. Either take the easy way and
712 settle for most ads blocked with the default configuration, or jump in and
713 tweak it for your personal surfing habits and preferences.
715 Secondly, a brief explanation of Privoxy's "actions". "Actions" in this
716 context, are the directives we use to tell Privoxy to perform some task
717 relating to HTTP transactions (i.e. web browsing). We tell Privoxy to take some
718 "action". Each action has a unique name and function. While there are many
719 potential actions in Privoxy's arsenal, only a few are used for ad blocking.
720 Actions, and action configuration files, are explained in depth below.
722 Actions are specified in Privoxy's configuration, followed by one or more URLs
723 to which the action should apply. URLs can actually be URL type patterns that
724 use wildcards so they can apply potentially to a range of similar URLs. The
725 actions, together with the URL patterns are called a section.
727 When you connect to a website, the full URL will either match one or more of
728 the sections as defined in Privoxy's configuration, or not. If so, then Privoxy
729 will perform the respective actions. If not, then nothing special happens.
730 Furthermore, web pages may contain embedded, secondary URLs that your web
731 browser will use to load additional components of the page, as it parses the
732 original page's HTML content. An ad image for instance, is just an URL embedded
733 in the page somewhere. The image itself may be on the same server, or a server
734 somewhere else on the Internet. Complex web pages will have many such embedded
737 The actions we need to know about for ad blocking are: block, handle-as-image,
738 and set-image-blocker:
740 * block - this action stops any contact between your browser and any URL
741 patterns that match this action's configuration. It can be used for
742 blocking ads, but also anything that is determined to be unwanted. By
743 itself, it simply stops any communication with the remote server and sends
744 Privoxy's own built-in BLOCKED page instead to let you now what has
747 * handle-as-image - tells Privoxy to treat this URL as an image. Privoxy's
748 default configuration already does this for all common image types (e.g.
749 GIF), but there are many situations where this is not so easy to determine.
750 So we'll force it in these cases. This is particularly important for ad
751 blocking, since only if we know that it's an image of some kind, can we
752 replace it with an image of our choosing, instead of the Privoxy BLOCKED
753 page (which would only result in a "broken image" icon). There are some
754 limitations to this though. For instance, you can't just brute-force an
755 image substitution for an entire HTML page in most situations.
757 * set-image-blocker - tells Privoxy what to display in place of an ad image
758 that has hit a block rule. For this to come into play, the URL must match a
759 block action somewhere in the configuration, and, it must also match an
760 handle-as-image action.
762 The configuration options on what to display instead of the ad are:
764 pattern - a checkerboard pattern, so that an ad replacement is obvious.
767 blank - A very small empty GIF image is displayed. This is the so-called
768 "invisible" configuration option.
770 http://<URL> - A redirect to any image anywhere of the user's choosing
773 The quickest way to adjust any of these settings is with your browser through
774 the special Privoxy editor at http://config.privoxy.org/show-status (shortcut:
775 http://p.p/show-status). This is an internal page, and does not require
776 Internet access. Select the appropriate "actions" file, and click "Edit". It is
777 best to put personal or local preferences in user.action since this is not
778 meant to be overwritten during upgrades, and will over-ride the settings in
779 other files. Here you can insert new "actions", and URLs for ad blocking or
780 other purposes, and make other adjustments to the configuration. Privoxy will
781 detect these changes automatically.
783 A quick and simple step by step example:
785 * Right click on the ad image to be blocked, then select "Copy Link Location"
786 from the pop-up menu.
788 * Set your browser to http://config.privoxy.org/show-status
790 * Find user.action in the top section, and click on "Edit":
792 Figure 1. Actions Files in Use
796 * You should have a section with only block listed under "Actions:". If not,
797 click a "Insert new section below" button, and in the new section that just
798 appeared, click the Edit button right under the word "Actions:". This will
799 bring up a list of all actions. Find block near the top, and click in the
800 "Enabled" column, then "Submit" just below the list.
802 * Now, in the block actions section, click the "Add" button, and paste the
803 URL the browser got from "Copy Link Location". Remove the http:// at the
804 beginning of the URL. Then, click "Submit" (or "OK" if in a pop-up window).
806 * Now go back to the original page, and press SHIFT-Reload (or flush all
807 browser caches). The image should be gone now.
809 This is a very crude and simple example. There might be good reasons to use a
810 wildcard pattern match to include potentially similar images from the same
811 site. For a more extensive explanation of "patterns", and the entire actions
812 concept, see the Actions section.
814 For advanced users who want to hand edit their config files, you might want to
815 now go to the Actions Files Tutorial. The ideas explained therein also apply to
816 the web-based editor.
818 -------------------------------------------------------------------------------
822 Before launching Privoxy for the first time, you will want to configure your
823 browser(s) to use Privoxy as a HTTP and HTTPS (SSL) proxy. The default is
824 127.0.0.1 (or localhost) for the proxy address, and port 8118 (earlier versions
825 used port 8000). This is the one configuration step that must be done!
827 Please note that Privoxy can only proxy HTTP and HTTPS traffic. It will not
828 work with FTP or other protocols.
830 Figure 2. Proxy Configuration Showing Mozilla/Netscape HTTP and HTTPS (SSL)
835 With Firefox, this can be set under:
837 Tools -> Options -> General -> Connection Settings -> Manual Proxy
841 With Netscape (and Mozilla), this can be set under:
843 Edit -> Preferences -> Advanced -> Proxies -> HTTP Proxy
846 For Internet Explorer v.5-6:
848 Tools -> Internet Options -> Connections -> LAN Settings
850 Then, check "Use Proxy" and fill in the appropriate info (Address: 127.0.0.1,
851 Port: 8118). Include HTTPS (SSL), if you want HTTPS proxy support too
852 (sometimes labeled "Secure"). Make sure any checkboxes like "Use the same proxy
853 server for all protocols" is UNCHECKED. You want only HTTP and HTTPS (SSL)!
855 Figure 3. Proxy Configuration Showing Internet Explorer HTTP and HTTPS (Secure)
860 After doing this, flush your browser's disk and memory caches to force a
861 re-reading of all pages and to get rid of any ads that may be cached. Remove
862 any cookies, if you want Privoxy to manage that. You are now ready to start
863 enjoying the benefits of using Privoxy!
865 Privoxy itself is typically started by specifying the main configuration file
866 to be used on the command line. If no configuration file is specified on the
867 command line, Privoxy will look for a file named config in the current
868 directory. Except on Win32 where it will try config.txt.
870 -------------------------------------------------------------------------------
872 5.1. Red Hat, Fedora and Conectiva
874 A default Red Hat installation may not start Privoxy upon boot. It will use the
875 file /etc/privoxy/config as its main configuration file.
877 # /etc/rc.d/init.d/privoxy start
881 # service privoxy start
883 -------------------------------------------------------------------------------
887 We use a script. Note that Debian typically starts Privoxy upon booting per
888 default. It will use the file /etc/privoxy/config as its main configuration
891 # /etc/init.d/privoxy start
893 -------------------------------------------------------------------------------
897 We use a script. It will use the file /etc/privoxy/config as its main
898 configuration file. Note that SuSE starts Privoxy upon booting your PC.
902 -------------------------------------------------------------------------------
906 Click on the Privoxy Icon to start Privoxy. If no configuration file is
907 specified on the command line, Privoxy will look for a file named config.txt.
908 Note that Windows will automatically start Privoxy when the system starts if
909 you chose that option when installing.
911 Privoxy can run with full Windows service functionality. On Windows only, the
912 Privoxy program has two new command line arguments to install and uninstall
913 Privoxy as a service. See the Windows Installation instructions for details.
915 -------------------------------------------------------------------------------
917 5.5. Solaris, NetBSD, FreeBSD, HP-UX and others
919 Example Unix startup command:
921 # /usr/sbin/privoxy /etc/privoxy/config
923 -------------------------------------------------------------------------------
927 During installation, Privoxy is configured to start automatically when the
928 system restarts. You can start it manually by double-clicking on the Privoxy
929 icon in the Privoxy folder.
931 -------------------------------------------------------------------------------
935 During installation, Privoxy is configured to start automatically when the
936 system restarts. To start Privoxy manually, double-click on the
937 StartPrivoxy.command icon in the /Library/Privoxy folder. Or, type this command
940 /Library/Privoxy/StartPrivoxy.command
943 You will be prompted for the administrator password.
945 -------------------------------------------------------------------------------
949 Start Privoxy (with RUN <>NIL:) in your startnet script (AmiTCP), in s:
950 user-startup (RoadShow), as startup program in your startup script (Genesis),
951 or as startup action (Miami and MiamiDx). Privoxy will automatically quit when
952 you quit your TCP/IP stack (just ignore the harmless warning your TCP/IP stack
953 may display that Privoxy is still running).
955 -------------------------------------------------------------------------------
959 A script is again used. It will use the file /etc/privoxy/config as its main
962 /etc/init.d/privoxy start
965 Note that Privoxy is not automatically started at boot time by default. You can
966 change this with the rc-update command.
968 rc-update add privoxy default
971 -------------------------------------------------------------------------------
973 5.10. Command Line Options
975 Privoxy may be invoked with the following command-line options:
979 Print version info and exit. Unix only.
983 Print short usage info and exit. Unix only.
987 Don't become a daemon, i.e. don't fork and become process group leader, and
988 don't detach from controlling tty. Unix only.
992 On startup, write the process ID to FILE. Delete the FILE on exit. Failure
993 to create or delete the FILE is non-fatal. If no FILE option is given, no
994 PID file will be used. Unix only.
996 * --user USER[.GROUP]
998 After (optionally) writing the PID file, assume the user ID of USER, and if
999 included the GID of GROUP. Exit if the privileges are not sufficient to do
1004 Before changing to the user ID given in the --user option, chroot to that
1005 user's home directory, i.e. make the kernel pretend to the Privoxy process
1006 that the directory tree starts there. If set up carefully, this can limit
1007 the impact of possible vulnerabilities in Privoxy to the files contained in
1008 that hierarchy. Unix only.
1012 If no configfile is included on the command line, Privoxy will look for a
1013 file named "config" in the current directory (except on Win32 where it will
1014 look for "config.txt" instead). Specify full path to avoid confusion. If no
1015 config file is found, Privoxy will fail to start.
1017 On MS Windows only there are two additional command-line options to allow
1018 Privoxy to install and run as a service. See the Window Installation section
1021 -------------------------------------------------------------------------------
1023 6. Privoxy Configuration
1025 All Privoxy configuration is stored in text files. These files can be edited
1026 with a text editor. Many important aspects of Privoxy can also be controlled
1027 easily with a web browser.
1029 -------------------------------------------------------------------------------
1031 6.1. Controlling Privoxy with Your Web Browser
1033 Privoxy's user interface can be reached through the special URL http://
1034 config.privoxy.org/ (shortcut: http://p.p/), which is a built-in page and works
1035 without Internet access. You will see the following section:
1038 ? View & change the current configuration
1039 ? View the source code version numbers
1040 ? View the request headers.
1041 ? Look up which actions apply to a URL and why
1042 ? Toggle Privoxy on or off
1046 This should be self-explanatory. Note the first item leads to an editor for the
1047 actions files, which is where the ad, banner, cookie, and URL blocking magic is
1048 configured as well as other advanced features of Privoxy. This is an easy way
1049 to adjust various aspects of Privoxy configuration. The actions file, and other
1050 configuration files, are explained in detail below.
1052 "Toggle Privoxy On or Off" is handy for sites that might have problems with
1053 your current actions and filters. You can in fact use it as a test to see
1054 whether it is Privoxy causing the problem or not. Privoxy continues to run as a
1055 proxy in this case, but all manipulation is disabled, i.e. Privoxy acts like a
1056 normal forwarding proxy. There is even a toggle Bookmarklet offered, so that
1057 you can toggle Privoxy with one click from your browser.
1059 -------------------------------------------------------------------------------
1061 6.2. Configuration Files Overview
1063 For Unix, *BSD and Linux, all configuration files are located in /etc/privoxy/
1064 by default. For MS Windows, OS/2, and AmigaOS these are all in the same
1065 directory as the Privoxy executable. The name and number of configuration files
1066 has changed from previous versions, and is subject to change as development
1069 The installed defaults provide a reasonable starting point, though some
1070 settings may be aggressive by some standards. For the time being, the principle
1071 configuration files are:
1073 * The main configuration file is named config on Linux, Unix, BSD, OS/2, and
1074 AmigaOS and config.txt on Windows. This is a required file.
1076 * default.action (the main actions file) is used to define which "actions"
1077 relating to banner-blocking, images, pop-ups, content modification, cookie
1078 handling etc should be applied by default. It also defines many exceptions
1079 (both positive and negative) from this default set of actions that enable
1080 Privoxy to selectively eliminate the junk, and only the junk, on as many
1081 websites as possible.
1083 Multiple actions files may be defined in config. These are processed in the
1084 order they are defined. Local customizations and locally preferred
1085 exceptions to the default policies as defined in default.action (which you
1086 will most probably want to define sooner or later) are probably best
1087 applied in user.action, where you can preserve them across upgrades.
1088 standard.action is for Privoxy's internal use.
1090 There is also a web based editor that can be accessed from http://
1091 config.privoxy.org/show-status (Shortcut: http://p.p/show-status) for the
1092 various actions files.
1094 * "Filter files" (the filter file) can be used to re-write the raw page
1095 content, including viewable text as well as embedded HTML and JavaScript,
1096 and whatever else lurks on any given web page. The filtering jobs are only
1097 pre-defined here; whether to apply them or not is up to the actions files.
1098 default.filter includes various filters made available for use by the
1099 developers. Some are much more intrusive than others, and all should be
1100 used with caution. You may define additional filter files in config as you
1101 can with actions files. We suggest user.filter for any locally defined
1102 filters or customizations.
1104 The syntax of all configuration files has remained the same throughout the 3.x
1105 series. There have been enhancements, but no changes that would preclude the
1106 use of any configuration file from one version to the next. (There is one
1107 exception: +fast-redirects which has enhanced syntax and will require updating
1108 any local configs from earlier versions.)
1110 All files use the "#" character to denote a comment (the rest of the line will
1111 be ignored) and understand line continuation through placing a backslash ("\")
1112 as the very last character in a line. If the # is preceded by a backslash, it
1113 looses its special function. Placing a # in front of an otherwise valid
1114 configuration line to prevent it from being interpreted is called "commenting
1115 out" that line. Blank lines are ignored.
1117 The actions files and filter files can use Perl style regular expressions for
1118 maximum flexibility.
1120 After making any changes, there is no need to restart Privoxy in order for the
1121 changes to take effect. Privoxy detects such changes automatically. Note,
1122 however, that it may take one or two additional requests for the change to take
1123 effect. When changing the listening address of Privoxy, these "wake up"
1124 requests must obviously be sent to the old listening address.
1126 While under development, the configuration content is subject to change. The
1127 below documentation may not be accurate by the time you read this. Also, what
1128 constitutes a "default" setting, may change, so please check all your
1129 configuration files on important issues.
1131 -------------------------------------------------------------------------------
1133 7. The Main Configuration File
1135 Again, the main configuration file is named config on Linux/Unix/BSD and OS/2,
1136 and config.txt on Windows. Configuration lines consist of an initial keyword
1137 followed by a list of values, all separated by whitespace (any number of spaces
1138 or tabs). For example:
1140 confdir /etc/privoxy
1142 Assigns the value /etc/privoxy to the option confdir and thus indicates that
1143 the configuration directory is named "/etc/privoxy/".
1145 All options in the config file except for confdir and logdir are optional.
1146 Watch out in the below description for what happens if you leave them unset.
1148 The main config file controls all aspects of Privoxy's operation that are not
1149 location dependent (i.e. they apply universally, no matter where you may be
1152 -------------------------------------------------------------------------------
1154 7.1. Local Set-up Documentation
1156 If you intend to operate Privoxy for more users than just yourself, it might be
1157 a good idea to let them know how to reach you, what you block and why you do
1158 that, your policies, etc.
1160 -------------------------------------------------------------------------------
1166 Location of the Privoxy User Manual.
1170 A fully qualified URI
1178 http://www.privoxy.org/version/user-manual/ will be used, where version is
1179 the Privoxy version.
1183 The User Manual URI is the single best source of information on Privoxy,
1184 and is used for help links from some of the internal CGI pages. The manual
1185 itself is normally packaged with the binary distributions, so you probably
1186 want to set this to a locally installed copy.
1190 The best all purpose solution is simply to put the full local PATH to where
1191 the User Manual is located:
1193 user-manual /usr/share/doc/privoxy/user-manual
1195 The User Manual is then available to anyone with access to the proxy, by
1196 following the built-in URL: http://config.privoxy.org/user-manual/ (or the
1197 shortcut: http://p.p/user-manual/).
1199 If the documentation is not on the local system, it can be accessed from a
1202 user-manual http://example.com/privoxy/user-manual/
1204 +-----------------------------------------------------------------+
1206 |-----------------------------------------------------------------|
1207 |If set, this option should be the first option in the config |
1208 |file, because it is used while the config file is being read on |
1210 +-----------------------------------------------------------------+
1212 -------------------------------------------------------------------------------
1214 7.1.2. trust-info-url
1218 A URL to be displayed in the error page that users will see if access to an
1219 untrusted page is denied.
1227 Two example URL are provided
1231 No links are displayed on the "untrusted" error page.
1235 The value of this option only matters if the experimental trust mechanism
1236 has been activated. (See trustfile above.)
1238 If you use the trust mechanism, it is a good idea to write up some on-line
1239 documentation about your trust policy and to specify the URL(s) here. Use
1240 multiple times for multiple URLs.
1242 The URL(s) should be added to the trustfile as well, so users don't end up
1243 locked out from the information on why they were locked out in the first
1246 -------------------------------------------------------------------------------
1248 7.1.3. admin-address
1252 An email address to reach the proxy administrator.
1264 No email address is displayed on error pages and the CGI user interface.
1268 If both admin-address and proxy-info-url are unset, the whole "Local
1269 Privoxy Support" box on all generated pages will not be shown.
1271 -------------------------------------------------------------------------------
1273 7.1.4. proxy-info-url
1277 A URL to documentation about the local Privoxy setup, configuration or
1290 No link to local documentation is displayed on error pages and the CGI user
1295 If both admin-address and proxy-info-url are unset, the whole "Local
1296 Privoxy Support" box on all generated pages will not be shown.
1298 This URL shouldn't be blocked ;-)
1300 -------------------------------------------------------------------------------
1302 7.2. Configuration and Log File Locations
1304 Privoxy can (and normally does) use a number of other files for additional
1305 configuration, help and logging. This section of the configuration file tells
1306 Privoxy where to find those other files.
1308 The user running Privoxy, must have read permission for all configuration
1309 files, and write permission to any files that would be modified, such as log
1310 files and actions files.
1312 -------------------------------------------------------------------------------
1318 The directory where the other configuration files are located
1326 /etc/privoxy (Unix) or Privoxy installation dir (Windows)
1334 No trailing "/", please
1336 -------------------------------------------------------------------------------
1342 The directory where all logging takes place (i.e. where logfile and jarfile
1351 /var/log/privoxy (Unix) or Privoxy installation dir (Windows)
1359 No trailing "/", please
1361 -------------------------------------------------------------------------------
1367 The actions file(s) to use
1371 File name, relative to confdir, without the .action suffix
1375 standard # Internal purposes, no editing recommended
1377 default # Main actions file
1379 user # User customizations
1383 No actions are taken at all. Simple neutral proxying.
1387 Multiple actionsfile lines are permitted, and are in fact recommended!
1389 The default values include standard.action, which is used for internal
1390 purposes and should be loaded, default.action, which is the "main" actions
1391 file maintained by the developers, and user.action, where you can make your
1394 Actions files are where all the per site and per URL configuration is done
1395 for ad blocking, cookie management, privacy considerations, etc. There is
1396 no point in using Privoxy without at least one actions file.
1398 -------------------------------------------------------------------------------
1404 The filter file(s) to use
1408 File name, relative to confdir
1412 default.filter (Unix) or default.filter.txt (Windows)
1416 No textual content filtering takes place, i.e. all +filter{name} actions in
1417 the actions files are turned neutral.
1421 Multiple filterfile lines are permitted.
1423 The filter files contain content modification rules that use regular
1424 expressions. These rules permit powerful changes on the content of Web
1425 pages, and optionally the headers as well, e.g., you could disable your
1426 favorite JavaScript annoyances, re-write the actual displayed text, or just
1427 have some fun playing buzzword bingo with web pages.
1429 The +filter{name} actions rely on the relevant filter (name) to be defined
1432 A pre-defined filter file called default.filter that contains a number of
1433 useful filters for common problems is included in the distribution. See the
1434 section on the filter action for a list.
1436 It is recommended to place any locally adapted filters into a separate
1437 file, such as user.filter.
1439 -------------------------------------------------------------------------------
1449 File name, relative to logdir
1453 logfile (Unix) or privoxy.log (Windows)
1457 No log file is used, all log messages go to the console (STDERR).
1461 The logfile is where all logging and error messages are written. The level
1462 of detail and number of messages are set with the debug option (see below).
1463 The logfile can be useful for tracking down a problem with Privoxy (e.g.,
1464 it's not blocking an ad you think it should block) but in most cases you
1465 probably will never look at it.
1467 Your logfile will grow indefinitely, and you will probably want to
1468 periodically remove it. On Unix systems, you can do this with a cron job
1469 (see "man cron"). For Red Hat, a logrotate script has been included.
1471 On SuSE Linux systems, you can place a line like "/var/log/privoxy.* +1024k
1472 644 nobody.nogroup" in /etc/logfiles, with the effect that cron.daily will
1473 automatically archive, gzip, and empty the log, when it exceeds 1M size.
1475 Any log files must be writable by whatever user Privoxy is being run as
1476 (default on UNIX, user id is "privoxy").
1478 -------------------------------------------------------------------------------
1484 The file to store intercepted cookies in
1488 File name, relative to logdir
1492 Unset (commented out). When activated: jarfile (Unix) or privoxy.jar
1497 Intercepted cookies are not stored in a dedicated log file.
1501 The jarfile may grow to ridiculous sizes over time.
1503 If debug 8 (show header parsing) is enabled, cookies are written to the
1504 logfile with the rest of the headers.
1506 -------------------------------------------------------------------------------
1512 The name of the trust file to use
1516 File name, relative to confdir
1520 Unset (commented out). When activated: trust (Unix) or trust.txt (Windows)
1524 The entire trust mechanism is disabled.
1528 The trust mechanism is an experimental feature for building white-lists and
1529 should be used with care. It is NOT recommended for the casual user.
1531 If you specify a trust file, Privoxy will only allow access to sites that
1532 are specified in the trustfile. Sites can be listed in one of two ways:
1534 Prepending a ~ character limits access to this site only (and any sub-paths
1535 within this site), e.g. ~www.example.com allows access to ~www.example.com/
1536 features/news.html, etc.
1538 Or, you can designate sites as trusted referrers, by prepending the name
1539 with a + character. The effect is that access to untrusted sites will be
1540 granted -- but only if a link from this trusted referrer was used to get
1541 there. The link target will then be added to the "trustfile" so that
1542 future, direct accesses will be granted. Sites added via this mechanism do
1543 not become trusted referrers themselves (i.e. they are added with a ~
1544 designation). There is a limit of 512 such entries, after which new entries
1547 If you use the + operator in the trust file, it may grow considerably over
1550 It is recommended that Privoxy be compiled with the --disable-force,
1551 --disable-toggle and --disable-editor options, if this feature is to be
1554 Possible applications include limiting Internet access for children.
1556 -------------------------------------------------------------------------------
1560 These options are mainly useful when tracing a problem. Note that you might
1561 also want to invoke Privoxy with the --no-daemon command line option when
1564 -------------------------------------------------------------------------------
1570 Key values that determine what information gets logged to the logfile.
1578 12289 (i.e.: URLs plus informational and warning messages)
1582 Nothing gets logged.
1586 The available debug levels are:
1588 debug 1 # show each GET/POST/CONNECT request
1589 debug 2 # show each connection status
1590 debug 4 # show I/O status
1591 debug 8 # show header parsing
1592 debug 16 # log all data into the logfile
1593 debug 32 # debug force feature
1594 debug 64 # debug regular expression filter
1595 debug 128 # debug fast redirects
1596 debug 256 # debug GIF de-animation
1597 debug 512 # Common Log Format
1598 debug 1024 # debug kill pop-ups
1599 debug 2048 # CGI user interface
1600 debug 4096 # Startup banner and warnings.
1601 debug 8192 # Non-fatal errors
1603 To select multiple debug levels, you can either add them or use multiple
1606 A debug level of 1 is informative because it will show you each request as
1607 it happens. 1, 4096 and 8192 are highly recommended so that you will notice
1608 when things go wrong. The other levels are probably only of interest if you
1609 are hunting down a specific problem. They can produce a hell of an output
1612 The reporting of fatal errors (i.e. ones which crash Privoxy) is always on
1613 and cannot be disabled.
1615 If you want to use CLF (Common Log Format), you should set "debug 512" ONLY
1616 and not enable anything else.
1618 -------------------------------------------------------------------------------
1620 7.3.2. single-threaded
1624 Whether to run only one server thread
1636 Multi-threaded (or, where unavailable: forked) operation, i.e. the ability
1637 to serve multiple requests simultaneously.
1641 This option is only there for debug purposes and you should never need to
1642 use it. It will drastically reduce performance.
1644 -------------------------------------------------------------------------------
1646 7.4. Access Control and Security
1648 This section of the config file controls the security-relevant aspects of
1649 Privoxy's configuration.
1651 -------------------------------------------------------------------------------
1653 7.4.1. listen-address
1657 The IP address and TCP port on which Privoxy will listen for client
1670 Bind to 127.0.0.1 (localhost), port 8118. This is suitable and recommended
1671 for home users who run Privoxy on the same machine as their browser.
1675 You will need to configure your browser(s) to this proxy address and port.
1677 If you already have another service running on port 8118, or if you want to
1678 serve requests from other machines (e.g. on your local network) as well,
1679 you will need to override the default.
1681 If you leave out the IP address, Privoxy will bind to all interfaces
1682 (addresses) on your machine and may become reachable from the Internet. In
1683 that case, consider using access control lists (ACL's, see below), and/or a
1686 If you open Privoxy to untrusted users, you will also want to turn off the
1687 enable-edit-actions and enable-remote-toggle options!
1691 Suppose you are running Privoxy on a machine which has the address
1692 192.168.0.1 on your local private network (192.168.0.0) and has another
1693 outside connection with a different address. You want it to serve requests
1696 listen-address 192.168.0.1:8118
1698 -------------------------------------------------------------------------------
1704 Initial state of "toggle" status
1716 Act as if toggled on
1720 If set to 0, Privoxy will start in "toggled off" mode, i.e. behave like a
1721 normal, content-neutral proxy where all ad blocking, filtering, etc are
1722 disabled. See enable-remote-toggle below. This is not really useful
1723 anymore, since toggling is much easier via the web interface than via
1724 editing the conf file.
1726 The windows version will only display the toggle icon in the system tray if
1727 this option is present.
1729 -------------------------------------------------------------------------------
1731 7.4.3. enable-remote-toggle
1735 Whether or not the web-based toggle feature may be used
1747 The web-based toggle feature is disabled.
1751 When toggled off, Privoxy acts like a normal, content-neutral proxy, i.e.
1752 it acts as if none of the actions applied to any URL.
1754 For the time being, access to the toggle feature can not be controlled
1755 separately by "ACLs" or HTTP authentication, so that everybody who can
1756 access Privoxy (see "ACLs" and listen-address above) can toggle it for all
1757 users. So this option is not recommended for multi-user environments with
1760 Note that you must have compiled Privoxy with support for this feature,
1761 otherwise this option has no effect.
1763 -------------------------------------------------------------------------------
1765 7.4.4. enable-remote-http-toggle
1769 Whether or not Privoxy recognizes special HTTP headers to change its
1782 Privoxy ignores special HTTP headers.
1786 When toggled on, the client can change Privoxy's behaviour by setting
1787 special HTTP headers. Currently the only supported special header is
1788 "X-Filter: No", to disable filtering for the ongoing request, even if it is
1789 enabled in one of the action files.
1791 If you are using Privoxy in a multi-user environment or with untrustworthy
1792 clients and want to enforce filtering, you will have to disable this
1793 option, otherwise you can ignore it.
1795 -------------------------------------------------------------------------------
1797 7.4.5. enable-edit-actions
1801 Whether or not the web-based actions file editor may be used
1813 The web-based actions file editor is disabled.
1817 For the time being, access to the editor can not be controlled separately
1818 by "ACLs" or HTTP authentication, so that everybody who can access Privoxy
1819 (see "ACLs" and listen-address above) can modify its configuration for all
1820 users. So this option is not recommended for multi-user environments with
1823 Note that you must have compiled Privoxy with support for this feature,
1824 otherwise this option has no effect.
1826 -------------------------------------------------------------------------------
1828 7.4.6. ACLs: permit-access and deny-access
1832 Who can access what.
1836 src_addr[/src_masklen] [dst_addr[/dst_masklen]]
1838 Where src_addr and dst_addr are IP addresses in dotted decimal notation or
1839 valid DNS names, and src_masklen and dst_masklen are subnet masks in CIDR
1840 notation, i.e. integer values from 2 to 30 representing the length (in
1841 bits) of the network address. The masks and the whole destination part are
1850 Don't restrict access further than implied by listen-address
1854 Access controls are included at the request of ISPs and systems
1855 administrators, and are not usually needed by individual users. For a
1856 typical home user, it will normally suffice to ensure that Privoxy only
1857 listens on the localhost (127.0.0.1) or internal (home) network address by
1858 means of the listen-address option.
1860 Please see the warnings in the FAQ that this proxy is not intended to be a
1861 substitute for a firewall or to encourage anyone to defer addressing basic
1862 security weaknesses.
1864 Multiple ACL lines are OK. If any ACLs are specified, then the Privoxy
1865 talks only to IP addresses that match at least one permit-access line and
1866 don't match any subsequent deny-access line. In other words, the last match
1867 wins, with the default being deny-access.
1869 If Privoxy is using a forwarder (see forward below) for a particular
1870 destination URL, the dst_addr that is examined is the address of the
1871 forwarder and NOT the address of the ultimate target. This is necessary
1872 because it may be impossible for the local Privoxy to determine the IP
1873 address of the ultimate target (that's often what gateways are used for).
1875 You should prefer using IP addresses over DNS names, because the address
1876 lookups take time. All DNS names must resolve! You can not use domain
1877 patterns like "*.org" or partial domain names. If a DNS name resolves to
1878 multiple IP addresses, only the first one is used.
1880 Denying access to particular sites by ACL may have undesired side effects
1881 if the site in question is hosted on a machine which also hosts other
1886 Explicitly define the default behavior if no ACL and listen-address are
1887 set: "localhost" is OK. The absence of a dst_addr implies that all
1888 destination addresses are OK:
1890 permit-access localhost
1892 Allow any host on the same class C subnet as www.privoxy.org access to
1893 nothing but www.example.com:
1895 permit-access www.privoxy.org/24 www.example.com/32
1897 Allow access from any host on the 26-bit subnet 192.168.45.64 to anywhere,
1898 with the exception that 192.168.45.73 may not access
1899 www.dirty-stuff.example.com:
1901 permit-access 192.168.45.64/26
1902 deny-access 192.168.45.73 www.dirty-stuff.example.com
1904 -------------------------------------------------------------------------------
1910 Maximum size of the buffer for content filtering.
1922 Use a 4MB (4096 KB) limit.
1926 For content filtering, i.e. the +filter and +deanimate-gif actions, it is
1927 necessary that Privoxy buffers the entire document body. This can be
1928 potentially dangerous, since a server could just keep sending data
1929 indefinitely and wait for your RAM to exhaust -- with nasty consequences.
1932 When a document buffer size reaches the buffer-limit, it is flushed to the
1933 client unfiltered and no further attempt to filter the rest of the document
1934 is made. Remember that there may be multiple threads running, which might
1935 require up to buffer-limit Kbytes each, unless you have enabled
1936 "single-threaded" above.
1938 -------------------------------------------------------------------------------
1942 This feature allows routing of HTTP requests through a chain of multiple
1943 proxies. It can be used to better protect privacy and confidentiality when
1944 accessing specific domains by routing requests to those domains through an
1945 anonymous public proxy. Or to use a caching proxy to speed up browsing. Or
1946 chaining to a parent proxy may be necessary because the machine that Privoxy
1947 runs on has no direct Internet access.
1949 Also specified here are SOCKS proxies. Privoxy supports the SOCKS 4 and SOCKS
1952 -------------------------------------------------------------------------------
1958 To which parent HTTP proxy specific requests should be routed.
1962 target_pattern http_parent[:port]
1964 where target_pattern is a URL pattern that specifies to which requests
1965 (i.e. URLs) this forward rule shall apply. Use / to denote "all URLs".
1966 http_parent[:port] is the DNS name or IP address of the parent HTTP proxy
1967 through which the requests should be forwarded, optionally followed by its
1968 listening port (default: 8080). Use a single dot (.) to denote "no
1977 Don't use parent HTTP proxies.
1981 If http_parent is ".", then requests are not forwarded to another HTTP
1982 proxy but are made directly to the web servers.
1984 Multiple lines are OK, they are checked in sequence, and the last match
1989 Everything goes to an example anonymizing proxy, except SSL on port 443
1990 (which it doesn't handle):
1992 forward / anon-proxy.example.org:8080
1995 Everything goes to our example ISP's caching proxy, except for requests to
1998 forward / caching-proxy.example-isp.net:8000
1999 forward .example-isp.net .
2001 -------------------------------------------------------------------------------
2003 7.5.2. forward-socks4 and forward-socks4a
2007 Through which SOCKS proxy (and to which parent HTTP proxy) specific
2008 requests should be routed.
2012 target_pattern socks_proxy[:port] http_parent[:port]
2014 where target_pattern is a URL pattern that specifies to which requests
2015 (i.e. URLs) this forward rule shall apply. Use / to denote "all URLs".
2016 http_parent and socks_proxy are IP addresses in dotted decimal notation or
2017 valid DNS names (http_parent may be "." to denote "no HTTP forwarding"),
2018 and the optional port parameters are TCP ports, i.e. integer values from 1
2027 Don't use SOCKS proxies.
2031 Multiple lines are OK, they are checked in sequence, and the last match
2034 The difference between forward-socks4 and forward-socks4a is that in the
2035 SOCKS 4A protocol, the DNS resolution of the target hostname happens on the
2036 SOCKS server, while in SOCKS 4 it happens locally.
2038 If http_parent is ".", then requests are not forwarded to another HTTP
2039 proxy but are made (HTTP-wise) directly to the web servers, albeit through
2044 From the company example.com, direct connections are made to all "internal"
2045 domains, but everything outbound goes through their ISP's proxy by way of
2046 example.com's corporate SOCKS 4A gateway to the Internet.
2048 forward-socks4a / socks-gw.example.com:1080 www-cache.example-isp.net:8080
2049 forward .example.com .
2051 A rule that uses a SOCKS 4 gateway for all destinations but no HTTP parent
2054 forward-socks4 / socks-gw.example.com:1080 .
2056 To chain Privoxy and Tor, both running on the same system, you should use
2059 forward-socks4 / 127.0.0.1:9050 .
2061 The public Tor network can't be used to reach your local network, therefore
2062 it's a good idea to make some exceptions:
2064 forward 192.168.*.*/ .
2066 forward 127.*.*.*/ .
2068 Unencrypted connections to systems in these address ranges will be as (un)
2069 secure as the local network is, but the alternative is that you can't reach
2072 If you also want to be able to reach servers in your local network by using
2073 their names, you will need additional exceptions that look like this:
2075 forward localhost/ .
2077 -------------------------------------------------------------------------------
2079 7.5.3. Advanced Forwarding Examples
2081 If you have links to multiple ISPs that provide various special content only to
2082 their subscribers, you can configure multiple Privoxies which have connections
2083 to the respective ISPs to act as forwarders to each other, so that your users
2084 can see the internal content of all ISPs.
2086 Assume that host-a has a PPP connection to isp-a.net. And host-b has a PPP
2087 connection to isp-b.net. Both run Privoxy. Their forwarding configuration can
2093 forward .isp-b.net host-b:8118
2098 forward .isp-a.net host-a:8118
2100 Now, your users can set their browser's proxy to use either host-a or host-b
2101 and be able to browse the internal content of both isp-a and isp-b.
2103 If you intend to chain Privoxy and squid locally, then chain as browser ->
2104 squid -> privoxy is the recommended way.
2106 Assuming that Privoxy and squid run on the same box, your squid configuration
2107 could then look like this:
2109 # Define Privoxy as parent proxy (without ICP)
2110 cache_peer 127.0.0.1 parent 8118 7 no-query
2112 # Define ACL for protocol FTP
2115 # Do not forward FTP requests to Privoxy
2116 always_direct allow ftp
2118 # Forward all the rest to Privoxy
2119 never_direct allow all
2121 You would then need to change your browser's proxy settings to squid's address
2122 and port. Squid normally uses port 3128. If unsure consult http_port in
2125 You could just as well decide to only forward requests for Windows executables
2126 through a virus-scanning parent proxy, say, on antivir.example.com, port 8010:
2129 forward /.*\.(exe|com|dll|zip)$ antivir.example.com:8010
2131 -------------------------------------------------------------------------------
2133 7.5.4. forwarded-connect-retries
2137 How often Privoxy retries if a forwarded connection request fails.
2149 Forwarded connections are treated like direct connections and no retry
2154 forwarded-connect-retries is mainly interesting for socks4a connections,
2155 where Privoxy can't detect why the connections failed. The connection might
2156 have failed because of a DNS timeout in which case a retry makes sense, but
2157 it might also have failed because the server doesn't exist or isn't
2158 reachable. In this case the retry will just delay the appearance of
2159 Privoxy's error message.
2161 Only use this option, if you are getting many forwarding related error
2162 messages, that go away when you try again manually. Start with a small
2163 value and check Privoxy's logfile from time to time, to see how many
2164 retries are usually needed.
2168 forwarded-connect-retries 1
2170 -------------------------------------------------------------------------------
2172 7.6. Windows GUI Options
2174 Privoxy has a number of options specific to the Windows GUI interface:
2176 If "activity-animation" is set to 1, the Privoxy icon will animate when
2177 "Privoxy" is active. To turn off, set to 0.
2179 activity-animation 1
2182 If "log-messages" is set to 1, Privoxy will log messages to the console window:
2187 If "log-buffer-size" is set to 1, the size of the log buffer, i.e. the amount
2188 of memory used for the log messages displayed in the console window, will be
2189 limited to "log-max-lines" (see below).
2191 Warning: Setting this to 0 will result in the buffer to grow infinitely and eat
2197 log-max-lines is the maximum number of lines held in the log buffer. See above.
2202 If "log-highlight-messages" is set to 1, Privoxy will highlight portions of the
2203 log messages with a bold-faced font:
2205 log-highlight-messages 1
2208 The font used in the console window:
2210 log-font-name Comic Sans MS
2213 Font size used in the console window:
2218 "show-on-task-bar" controls whether or not Privoxy will appear as a button on
2219 the Task bar when minimized:
2224 If "close-button-minimizes" is set to 1, the Windows close button will minimize
2225 Privoxy instead of closing the program (close with the exit option on the File
2228 close-button-minimizes 1
2231 The "hide-console" option is specific to the MS-Win console version of Privoxy.
2232 If this option is used, Privoxy will disconnect from and hide the command
2238 -------------------------------------------------------------------------------
2242 The actions files are used to define what actions Privoxy takes for which URLs,
2243 and thus determines how ad images, cookies and various other aspects of HTTP
2244 content and transactions are handled, and on which sites (or even parts
2245 thereof). There are a number of such actions, with a wide range of
2246 functionality. Each action does something a little different. These actions
2247 give us a veritable arsenal of tools with which to exert our control,
2248 preferences and independence. Actions can be combined so that their effects are
2249 aggregated when applied against a given set of URLs.
2251 There are three action files included with Privoxy with differing purposes:
2253 * default.action - is the primary action file that sets the initial values
2254 for all actions. It is intended to provide a base level of functionality
2255 for Privoxy's array of features. So it is a set of broad rules that should
2256 work reasonably well as-is for most users. This is the file that the
2257 developers are keeping updated, and making available to users. The user's
2258 preferences as set in standard.action, e.g. either Cautious (the default),
2259 Medium, or Advanced (see below).
2261 * user.action - is intended to be for local site preferences and exceptions.
2262 As an example, if your ISP or your bank has specific requirements, and need
2263 special handling, this kind of thing should go here. This file will not be
2266 * standard.action - is used by the web based editor at http://
2267 config.privoxy.org/edit-actions-list?f=default, to set various pre-defined
2268 sets of rules for the default actions section in default.action.
2270 Edit Set to Cautious Set to Medium Set to Advanced
2272 These have increasing levels of aggressiveness and have no influence on
2273 your browsing unless you select them explicitly in the editor. A default
2274 installation should be pre-set to Cautious (versions prior to 3.0.5 were
2275 set to Medium). New users should try this for a while before adjusting the
2276 settings to more aggressive levels.
2278 The Edit button allows you to turn each action on/off individually for
2279 fine-tuning. The Cautious button changes the actions list to low/safe
2280 settings which will activate a minimal set of Privoxy's features, and
2281 subsequently there will be less of a chance for accidental problems. The
2282 Medium button sets the list to a medium level of ad blocking and a low
2283 level set of privacy features. The Advanced button sets the list to a high
2284 level of ad blocking and medium level of privacy. See the chart below. The
2285 latter three buttons over-ride any changes via with the Edit button. More
2286 fine-tuning can be done in the lower sections of this internal page.
2288 It is not recommend to edit the standard.action file itself.
2290 The default profiles, and their associated actions, as pre-defined in
2291 standard.action are:
2293 Table 1. Default Configurations
2295 +-------------------------------------------------------------------------+
2296 |Feature |Cautious |Medium |Advanced |
2297 |------------------+-----------------+------------------+-----------------|
2298 |Ad-blocking |medium |high |high |
2299 |Aggressiveness | | | |
2300 |------------------+-----------------+------------------+-----------------|
2301 |Ad-filtering by |no |yes |yes |
2303 |------------------+-----------------+------------------+-----------------|
2304 |Ad-filtering by |no |no |yes |
2306 |------------------+-----------------+------------------+-----------------|
2307 |Pop-up killing |blocks only |blocks only |all |
2308 |------------------+-----------------+------------------+-----------------|
2309 |Privacy Features |low |medium |medium/high |
2310 |------------------+-----------------+------------------+-----------------|
2311 |Cookie handling |none |session-only |kill |
2312 |------------------+-----------------+------------------+-----------------|
2313 |Referer forging |no |yes |yes |
2314 |------------------+-----------------+------------------+-----------------|
2315 |GIF de-animation |no |yes |yes |
2316 |------------------+-----------------+------------------+-----------------|
2317 |Fast redirects |no |no |yes |
2318 |------------------+-----------------+------------------+-----------------|
2319 |HTML taming |no |yes |yes |
2320 |------------------+-----------------+------------------+-----------------|
2321 |JavaScript taming |no |yes |yes |
2322 |------------------+-----------------+------------------+-----------------|
2323 |Web-bug killing |no |yes |yes |
2324 |------------------+-----------------+------------------+-----------------|
2325 |Image tag |no |no |yes |
2327 +-------------------------------------------------------------------------+
2329 The list of actions files to be used are defined in the main configuration
2330 file, and are processed in the order they are defined (e.g. default.action is
2331 typically process before user.action). The content of these can all be viewed
2332 and edited from http://config.privoxy.org/show-status. The over-riding
2333 principle when applying actions, is that the last action that matches a given
2334 URL, wins. The broadest, most general rules go first (defined in
2335 default.action), followed by any exceptions (typically also in default.action),
2336 which are then followed lastly by any local preferences (typically in
2337 user.action). Generally, user.action has the last word.
2339 An actions file typically has multiple sections. If you want to use "aliases"
2340 in an actions file, you have to place the (optional) alias section at the top
2341 of that file. Then comes the default set of rules which will apply universally
2342 to all sites and pages (be very careful with using such a universal set in
2343 user.action or any other actions file after default.action, because it will
2344 override the result from consulting any previous file). And then below that,
2345 exceptions to the defined universal policies. You can regard user.action as an
2346 appendix to default.action, with the advantage that is a separate file, which
2347 makes preserving your personal settings across Privoxy upgrades easier.
2349 Actions can be used to block anything you want, including ads, banners, or just
2350 some obnoxious URL that you would rather not see. Cookies can be accepted or
2351 rejected, or accepted only during the current browser session (i.e. not written
2352 to disk), content can be modified, JavaScripts tamed, user-tracking fooled, and
2353 much more. See below for a complete list of actions.
2355 -------------------------------------------------------------------------------
2357 8.1. Finding the Right Mix
2359 Note that some actions, like cookie suppression or script disabling, may render
2360 some sites unusable that rely on these techniques to work properly. Finding the
2361 right mix of actions is not always easy and certainly a matter of personal
2362 taste. And, things can always change, requiring refinements in the
2363 configuration. In general, it can be said that the more "aggressive" your
2364 default settings (in the top section of the actions file) are, the more
2365 exceptions for "trusted" sites you will have to make later. If, for example,
2366 you want to crunch all cookies per default, you'll have to make exceptions from
2367 that rule for sites that you regularly use and that require cookies for
2368 actually useful purposes, like maybe your bank, favorite shop, or newspaper.
2370 We have tried to provide you with reasonable rules to start from in the
2371 distribution actions files. But there is no general rule of thumb on these
2372 things. There just are too many variables, and sites are constantly changing.
2373 Sooner or later you will want to change the rules (and read this chapter again
2376 -------------------------------------------------------------------------------
2380 The easiest way to edit the actions files is with a browser by using our
2381 browser-based editor, which can be reached from http://config.privoxy.org/
2382 show-status. The editor allows both fine-grained control over every single
2383 feature on a per-URL basis, and easy choosing from wholesale sets of defaults
2384 like "Cautious", "Medium" or "Advanced". Warning: the "Advanced" setting is
2385 more aggressive, and will be more likely to cause problems for some sites.
2386 Experienced users only!
2388 If you prefer plain text editing to GUIs, you can of course also directly edit
2389 the the actions files with your favorite text editor. Look at default.action
2390 which is richly commented with many good examples.
2392 -------------------------------------------------------------------------------
2394 8.3. How Actions are Applied to URLs
2396 Actions files are divided into sections. There are special sections, like the "
2397 alias" sections which will be discussed later. For now let's concentrate on
2398 regular sections: They have a heading line (often split up to multiple lines
2399 for readability) which consist of a list of actions, separated by whitespace
2400 and enclosed in curly braces. Below that, there is a list of URL patterns, each
2403 To determine which actions apply to a request, the URL of the request is
2404 compared to all patterns in each "action file" file. Every time it matches, the
2405 list of applicable actions for the URL is incrementally updated, using the
2406 heading of the section in which the pattern is located. If multiple matches for
2407 the same URL set the same action differently, the last match wins. If not, the
2408 effects are aggregated. E.g. a URL might match a regular section with a heading
2409 line of { +handle-as-image }, then later another one with just { +block },
2410 resulting in both actions to apply. And there may well be cases where you will
2411 want to combine actions together. Such a section then might look like:
2413 { +handle-as-image +block }
2414 # Block these as if they were images. Send no block page.
2416 media.example.com/.*banners
2417 .example.com/images/ads/
2419 You can trace this process for any given URL by visiting http://
2420 config.privoxy.org/show-url-info.
2422 Examples and more detail on this is provided in the Appendix, Troubleshooting:
2423 Anatomy of an Action section.
2425 -------------------------------------------------------------------------------
2429 As mentioned, Privoxy uses "patterns" to determine what actions might apply to
2430 which sites and pages your browser attempts to access. These "patterns" use
2431 wild card type pattern matching to achieve a high degree of flexibility. This
2432 allows one expression to be expanded and potentially match against many similar
2435 Generally, a Privoxy pattern has the form <domain>/<path>, where both the
2436 <domain> and <path> are optional. (This is why the special / pattern matches
2437 all URLs). Note that the protocol portion of the URL pattern (e.g. http://)
2438 should not be included in the pattern. This is assumed already!
2440 The pattern matching syntax is different for the domain and path parts of the
2441 URL. The domain part uses a simple globbing type matching technique, while the
2442 path part uses a more flexible "Regular Expressions (PCRE)" based syntax.
2446 is a domain-only pattern and will match any request to www.example.com,
2447 regardless of which document on that server is requested. So ALL pages in
2448 this domain would be covered by the scope of this action. Note that a
2449 simple example.com is different and would NOT match.
2453 means exactly the same. For domain-only patterns, the trailing / may be
2456 www.example.com/index.html
2458 matches only the single document /index.html on www.example.com.
2462 matches the document /index.html, regardless of the domain, i.e. on any web
2467 matches nothing, since it would be interpreted as a domain name and there
2468 is no top-level domain called .html. So its a mistake.
2470 -------------------------------------------------------------------------------
2472 8.4.1. The Domain Pattern
2474 The matching of the domain part offers some flexible options: if the domain
2475 starts or ends with a dot, it becomes unanchored at that end. For example:
2479 matches any domain that ENDS in .example.com
2483 matches any domain that STARTS with www.
2487 matches any domain that CONTAINS .example.. And, by the way, also included
2488 would be any files or documents that exist within that domain since no path
2489 limitations are specified. (Correctly speaking: It matches any FQDN that
2490 contains example as a domain.) This might be www.example.com,
2491 news.example.de, or www.example.net/cgi/testing.pl for instance. All these
2494 Additionally, there are wild-cards that you can use in the domain names
2495 themselves. These work similarly to shell globbing type wild-cards: "*"
2496 represents zero or more arbitrary characters (this is equivalent to the
2497 "Regular Expression" based syntax of ".*"), "?" represents any single character
2498 (this is equivalent to the regular expression syntax of a simple "."), and you
2499 can define "character classes" in square brackets which is similar to the same
2500 regular expression technique. All of this can be freely mixed:
2504 matches "adserver.example.com", "ads.example.com", etc but not
2509 matches all of the above, and then some.
2513 matches www.ipix.com, pictures.epix.com, a.b.c.d.e.upix.com etc.
2515 www[1-9a-ez].example.c*
2517 matches www1.example.com, www4.example.cc, wwwd.example.cy,
2518 wwwz.example.com etc., but not wwww.example.com.
2520 While flexibile, this is not the sophistication of full regular expression
2523 -------------------------------------------------------------------------------
2525 8.4.2. The Path Pattern
2527 Privoxy uses Perl compatible (PCRE) "Regular Expression" based syntax (through
2528 the PCRE library) for matching the path portion (after the slash), and is thus
2531 There is an Appendix with a brief quick-start into regular expressions, and
2532 full (very technical) documentation on PCRE regex syntax is available on-line
2533 at http://www.pcre.org/man.txt. You might also find the Perl man page on
2534 regular expressions (man perlre) useful, which is available on-line at http://
2535 perldoc.perl.org/perlre.html.
2537 Note that the path pattern is automatically left-anchored at the "/", i.e. it
2538 matches as if it would start with a "^" (regular expression speak for the
2539 beginning of a line).
2541 Please also note that matching in the path is CASE INSENSITIVE by default, but
2542 you can switch to case sensitive at any point in the pattern by using the "(?
2543 -i)" switch: www.example.com/(?-i)PaTtErN.* will match only documents whose
2544 path starts with PaTtErN in exactly this capitalization.
2548 Is equivalent to just ".example.com", since any documents within that
2549 domain are matched with or without the ".*" regular expression. This is
2552 .example.com/.*/index.html
2554 Will match any page in the domain of "example.com" that is named
2555 "index.html", and that is part of some path. For example, it matches
2556 "www.example.com/testing/index.html" but NOT "www.example.com/index.html"
2557 because the regular expression called for at least two "/'s", thus the path
2558 requirement. It also would match "www.example.com/testing/index_html",
2559 because of the special meta-character ".".
2561 .example.com/(.*/)?index\.html
2563 This regular expression is conditional so it will match any page named
2564 "index.html" regardless of path which in this case can have one or more "/
2565 's". And this one must contain exactly ".html" (but does not have to end
2568 .example.com/(.*/)(ads|banners?|junk)
2570 This regular expression will match any path of "example.com" that contains
2571 any of the words "ads", "banner", "banners" (because of the "?") or "junk".
2572 The path does not have to end in these words, just contain them.
2574 .example.com/(.*/)(ads|banners?|junk)/.*\.(jpe?g|gif|png)$
2576 This is very much the same as above, except now it must end in either
2577 ".jpg", ".jpeg", ".gif" or ".png". So this one is limited to common image
2580 There are many, many good examples to be found in default.action, and more
2581 tutorials below in Appendix on regular expressions.
2583 -------------------------------------------------------------------------------
2587 All actions are disabled by default, until they are explicitly enabled
2588 somewhere in an actions file. Actions are turned on if preceded with a "+", and
2589 turned off if preceded with a "-". So a +action means "do that action", e.g.
2590 +block means "please block URLs that match the following patterns", and -block
2591 means "don't block URLs that match the following patterns, even if +block
2592 previously applied."
2594 Again, actions are invoked by placing them on a line, enclosed in curly braces
2595 and separated by whitespace, like in {+some-action -some-other-action
2596 {some-parameter}}, followed by a list of URL patterns, one per line, to which
2597 they apply. Together, the actions line and the following pattern lines make up
2598 a section of the actions file.
2600 Actions fall into three categories:
2602 * Boolean, i.e the action can only be "enabled" or "disabled". Syntax:
2604 +name # enable action name
2605 -name # disable action name
2609 * Parameterized, where some value is required in order to enable this type of
2612 +name{param} # enable action and set parameter to param,
2613 # overwriting parameter from previous match if necessary
2614 -name # disable action. The parameter can be omitted
2616 Note that if the URL matches multiple positive forms of a parameterized
2617 action, the last match wins, i.e. the params from earlier matches are
2620 Example: +hide-user-agent{ Mozilla 1.0 }
2622 * Multi-value. These look exactly like parameterized actions, but they behave
2623 differently: If the action applies multiple times to the same URL, but with
2624 different parameters, all the parameters from all matches are remembered.
2625 This is used for actions that can be executed for the same request
2626 repeatedly, like adding multiple headers, or filtering through multiple
2629 +name{param} # enable action and add param to the list of parameters
2630 -name{param} # remove the parameter param from the list of parameters
2631 # If it was the last one left, disable the action.
2632 -name # disable this action completely and remove all parameters from the list
2634 Examples: +add-header{X-Fun-Header: Some text} and +filter{html-annoyances}
2636 If nothing is specified in any actions file, no "actions" are taken. So in this
2637 case Privoxy would just be a normal, non-blocking, non-anonymizing proxy. You
2638 must specifically enable the privacy and blocking features you need (although
2639 the provided default actions files will give a good starting point).
2641 Later defined actions always over-ride earlier ones. So exceptions to any rules
2642 you make, should come in the latter part of the file (or in a file that is
2643 processed later when using multiple actions files such as user.action). For
2644 multi-valued actions, the actions are applied in the order they are specified.
2645 Actions files are processed in the order they are defined in config (the
2646 default installation has three actions files). It also quite possible for any
2647 given URL pattern to match more than one pattern and thus more than one set of
2648 actions! Last match wins.
2650 The list of valid Privoxy actions are:
2652 -------------------------------------------------------------------------------
2658 Confuse log analysis, custom applications
2662 Sends a user defined HTTP header to the web server.
2670 Any string value is possible. Validity of the defined HTTP headers is not
2671 checked. It is recommended that you use the "X-" prefix for custom headers.
2675 This action may be specified multiple times, in order to define multiple
2676 headers. This is rarely needed for the typical user. If you don't know what
2677 "HTTP headers" are, you definitely don't need to worry about this one.
2681 +add-header{X-User-Tracking: sucks}
2683 -------------------------------------------------------------------------------
2689 Block ads or other unwanted content
2693 Requests for URLs to which this action applies are blocked, i.e. the
2694 requests are trapped by Privoxy and the requested URL is never retrieved,
2695 but is answered locally with a substitute page or image, as determined by
2696 the handle-as-image, set-image-blocker, and handle-as-empty-document
2709 Privoxy sends a special "BLOCKED" page for requests to blocked pages. This
2710 page contains links to find out why the request was blocked, and a
2711 click-through to the blocked content (the latter only if compiled with the
2712 force feature enabled). The "BLOCKED" page adapts to the available screen
2713 space -- it displays full-blown if space allows, or miniaturized and
2714 text-only if loaded into a small frame or window. If you are using Privoxy
2715 right now, you can take a look at the "BLOCKED" page.
2717 A very important exception occurs if both block and handle-as-image, apply
2718 to the same request: it will then be replaced by an image. If
2719 set-image-blocker (see below) also applies, the type of image will be
2720 determined by its parameter, if not, the standard checkerboard pattern is
2723 It is important to understand this process, in order to understand how
2724 Privoxy deals with ads and other unwanted content. Blocking is a core
2725 feature, and one upon which various other features depend.
2727 The filter action can perform a very similar task, by "blocking" banner
2728 images and other content through rewriting the relevant URLs in the
2729 document's HTML source, so they don't get requested in the first place.
2730 Note that this is a totally different technique, and it's easy to confuse
2733 Example usage (section):
2736 # Block and replace with "blocked" page
2737 .nasty-stuff.example.com
2739 {+block +handle-as-image}
2740 # Block and replace with image
2744 {+block +handle-as-empty-document}
2745 # Block and then ignore
2746 adserver.exampleclick.net/.*\.js$
2748 -------------------------------------------------------------------------------
2750 8.5.3. content-type-overwrite
2754 Stop useless download menus from popping up, or change the browser's
2759 Replaces the "Content-Type:" HTTP server header.
2771 The "Content-Type:" HTTP server header is used by the browser to decide
2772 what to do with the document. The value of this header can cause the
2773 browser to open a download menu instead of displaying the document by
2774 itself, even if the document's format is supported by the browser.
2776 The declared content type can also affect which rendering mode the browser
2777 chooses. If XHTML is delivered as "text/html", many browsers treat it as
2778 yet another broken HTML document. If it is send as "application/xml",
2779 browsers with XHTML support will only display it, if the syntax is correct.
2781 If you see a web site that proudly uses XHTML buttons, but sets
2782 "Content-Type: text/html", you can use Privoxy to overwrite it with
2783 "application/xml" and validate the web master's claim inside your
2784 XHTML-supporting browser. If the syntax is incorrect, the browser will
2787 You can also go the opposite direction: if your browser prints error
2788 messages instead of rendering a document falsely declared as XHTML, you can
2789 overwrite the content type with "text/html" and have it rendered as broken
2792 By default content-type-overwrite only replaces "Content-Type:" headers
2793 that look like some kind of text. If you want to overwrite it
2794 unconditionally, you have to combine it with force-text-mode. This
2795 limitation exists for a reason, think twice before circumventing it.
2797 Most of the time it's easier to enable filter-server-headers and replace
2798 this action with a custom regular expression. It allows you to activate it
2799 for every document of a certain site and it will still only replace the
2800 content types you aimed at.
2802 Of course you can apply content-type-overwrite to a whole site and then
2803 make URL based exceptions, but it's a lot more work to get the same
2806 Example usage (sections):
2808 # Check if www.example.net/ really uses valid XHTML
2809 {+content-type-overwrite {application/xml}}
2812 # but leave the content type unmodified if the URL looks like a style sheet
2813 {-content-type-overwrite}
2814 www.example.net/*.\.css$
2815 www.example.net/*.style
2817 -------------------------------------------------------------------------------
2819 8.5.4. crunch-client-header
2823 Remove a client header Privoxy has no dedicated action for.
2827 Deletes every header sent by the client that contains the string the user
2828 supplied as parameter.
2840 This action allows you to block client headers for which no dedicated
2841 Privoxy action exists. Privoxy will remove every client header that
2842 contains the string you supplied as parameter.
2844 Regular expressions are not supported and you can't use this action to
2845 block different headers in the same request, unless they contain the same
2848 crunch-client-header is only meant for quick tests. If you have to block
2849 several different headers, or only want to modify parts of them, you should
2850 enable filter-client-headers and create your own filter.
2852 +-----------------------------------------------------------------+
2854 |-----------------------------------------------------------------|
2855 |Don't block any header without understanding the consequences. |
2856 +-----------------------------------------------------------------+
2857 Example usage (section):
2859 # Block the non-existent "Privacy-Violation:" client header
2860 {+crunch-client-header {Privacy-Violation:}}
2864 -------------------------------------------------------------------------------
2866 8.5.5. crunch-if-none-match
2870 Prevent yet another way to track the user's steps between sessions.
2874 Deletes the "If-None-Match:" HTTP client header.
2886 Removing the "If-None-Match:" HTTP client header is useful for filter
2887 testing, where you want to force a real reload instead of getting status
2888 code "304" which would cause the browser to use a cached copy of the page.
2890 It is also useful to make sure the header isn't used as a cookie
2893 Blocking the "If-None-Match:" header shouldn't cause any caching problems,
2894 as long as the "If-Modified-Since:" header isn't blocked as well.
2896 It is recommended to use this action together with hide-if-modified-since
2897 and overwrite-last-modified.
2899 Example usage (section):
2901 # Let the browser revalidate cached documents without being tracked across sessions
2902 {+hide-if-modified-since {-60} \
2903 +overwrite-last-modified {randomize} \
2904 +crunch-if-none-match}
2907 -------------------------------------------------------------------------------
2909 8.5.6. crunch-incoming-cookies
2913 Prevent the web server from setting any cookies on your system
2917 Deletes any "Set-Cookie:" HTTP headers from server replies.
2929 This action is only concerned with incoming cookies. For outgoing cookies,
2930 use crunch-outgoing-cookies. Use both to disable cookies completely.
2932 It makes no sense at all to use this action in conjunction with the
2933 session-cookies-only action, since it would prevent the session cookies
2934 from being set. See also filter-content-cookies.
2938 +crunch-incoming-cookies
2940 -------------------------------------------------------------------------------
2942 8.5.7. crunch-server-header
2946 Remove a server header Privoxy has no dedicated action for.
2950 Deletes every header sent by the server that contains the string the user
2951 supplied as parameter.
2963 This action allows you to block server headers for which no dedicated
2964 Privoxy action exists. Privoxy will remove every server header that
2965 contains the string you supplied as parameter.
2967 Regular expressions are not supported and you can't use this action to
2968 block different headers in the same request, unless they contain the same
2971 crunch-server-header is only meant for quick tests. If you have to block
2972 several different headers, or only want to modify parts of them, you should
2973 enable filter-server-headers and create your own filter.
2975 +-----------------------------------------------------------------+
2977 |-----------------------------------------------------------------|
2978 |Don't block any header without understanding the consequences. |
2979 +-----------------------------------------------------------------+
2980 Example usage (section):
2982 # Crunch server headers that try to prevent caching
2983 {+crunch-server-header {no-cache}}
2986 -------------------------------------------------------------------------------
2988 8.5.8. crunch-outgoing-cookies
2992 Prevent the web server from reading any cookies from your system
2996 Deletes any "Cookie:" HTTP headers from client requests.
3008 This action is only concerned with outgoing cookies. For incoming cookies,
3009 use crunch-incoming-cookies. Use both to disable cookies completely.
3011 It makes no sense at all to use this action in conjunction with the
3012 session-cookies-only action, since it would prevent the session cookies
3017 +crunch-outgoing-cookies
3019 -------------------------------------------------------------------------------
3021 8.5.9. deanimate-gifs
3025 Stop those annoying, distracting animated GIF images.
3029 De-animate GIF animations, i.e. reduce them to their first or last image.
3041 This will also shrink the images considerably (in bytes, not pixels!). If
3042 the option "first" is given, the first frame of the animation is used as
3043 the replacement. If "last" is given, the last frame of the animation is
3044 used instead, which probably makes more sense for most banner animations,
3045 but also has the risk of not showing the entire last frame (if it is only a
3046 delta to an earlier frame).
3048 You can safely use this action with patterns that will also match non-GIF
3049 objects, because no attempt will be made at anything that doesn't look like
3054 +deanimate-gifs{last}
3056 -------------------------------------------------------------------------------
3058 8.5.10. downgrade-http-version
3062 Work around (very rare) problems with HTTP/1.1
3066 Downgrades HTTP/1.1 client requests and server replies to HTTP/1.0.
3078 This is a left-over from the time when Privoxy didn't support important
3079 HTTP/1.1 features well. It is left here for the unlikely case that you
3080 experience HTTP/1.1 related problems with some server out there. Not all
3081 (optional) HTTP/1.1 features are supported yet, so there is a chance you
3082 might need this action.
3084 Example usage (section):
3086 {+downgrade-http-version}
3087 problem-host.example.com
3089 -------------------------------------------------------------------------------
3091 8.5.11. fast-redirects
3095 Fool some click-tracking scripts and speed up indirect links.
3099 Detects redirection URLs and redirects the browser without contacting the
3100 redirection server first.
3108 + "simple-check" to just search for the string "http://" to detect
3111 + "check-decoded-url" to decode URLs (if necessary) before searching for
3116 Many sites, like yahoo.com, don't just link to other sites. Instead, they
3117 will link to some script on their own servers, giving the destination as a
3118 parameter, which will then redirect you to the final target. URLs resulting
3119 from this scheme typically look like: "http://www.example.org/
3120 click-tracker.cgi?target=http%3a//www.example.net/".
3122 Sometimes, there are even multiple consecutive redirects encoded in the
3123 URL. These redirections via scripts make your web browsing more traceable,
3124 since the server from which you follow such a link can see where you go to.
3125 Apart from that, valuable bandwidth and time is wasted, while your browser
3126 asks the server for one redirect after the other. Plus, it feeds the
3129 This feature is currently not very smart and is scheduled for improvement.
3130 If it is enabled by default, you will have to create some exceptions to
3131 this action. It can lead to failures in several ways:
3133 Not every URLs with other URLs as parameters is evil. Some sites offer a
3134 real service that requires this information to work. For example a
3135 validation service needs to know, which document to validate.
3136 fast-redirects assumes that every URL parameter that looks like another URL
3137 is a redirection target, and will always redirect to the last one. Most of
3138 the time the assumption is correct, but if it isn't, the user gets
3141 Another failure occurs if the URL contains other parameters after the URL
3142 parameter. The URL: "http://www.example.org/?redirect=http%3a//
3143 www.example.net/&foo=bar". contains the redirection URL "http://
3144 www.example.net/", followed by another parameter. fast-redirects doesn't
3145 know that and will cause a redirect to "http://www.example.net/&foo=bar".
3146 Depending on the target server configuration, the parameter will be
3147 silently ignored or lead to a "page not found" error. It is possible to fix
3148 these redirected requests with filter-client-headers but it requires a
3151 To detect a redirection URL, fast-redirects only looks for the string
3152 "http://", either in plain text (invalid but often used) or encoded as
3153 "http%3a//". Some sites use their own URL encoding scheme, encrypt the
3154 address of the target server or replace it with a database id. In theses
3155 cases fast-redirects is fooled and the request reaches the redirection
3156 server where it probably gets logged.
3160 { +fast-redirects{simple-check} }
3163 { +fast-redirects{check-decoded-url} }
3164 another.example.com/testing
3166 -------------------------------------------------------------------------------
3172 Get rid of HTML and JavaScript annoyances, banner advertisements (by size),
3173 do fun text replacements, etc.
3177 All files of text-based type, most notably HTML and JavaScript, to which
3178 this action applies, are filtered on-the-fly through the specified regular
3179 expression based substitutions. (Note: as of version 3.0.3 plain text
3180 documents are exempted from filtering, because web servers often use the
3181 text/plain MIME type for all files whose type they don't know.) By default,
3182 filtering works only on the raw document content itself (that which can be
3183 seen with View Source), not the headers.
3191 The name of a filter, as defined in the filter file. Filters can be defined
3192 in one or more files as defined by the filterfile option in the config file
3193 . default.filter is the collection of filters supplied by the developers.
3194 Locally defined filters should go in their own file, such as user.filter.
3196 When used in its negative form, and without parameters, all filtering is
3197 completely disabled.
3201 For your convenience, there are a number of pre-defined filters available
3202 in the distribution filter file that you can use. See the examples below
3205 Filtering requires buffering the page content, which may appear to slow
3206 down page rendering since nothing is displayed until all content has passed
3207 the filters. (It does not really take longer, but seems that way since the
3208 page is not incrementally displayed.) This effect will be more noticeable
3209 on slower connections.
3211 "Rolling your own" filters requires a knowledge of "Regular Expressions"
3212 and "HTML". This is very powerful feature, and potentially very intrusive.
3215 The amount of data that can be filtered is limited to the buffer-limit
3216 option in the main config file. The default is 4096 KB (4 Megs). Once this
3217 limit is exceeded, the buffered data, and all pending data, is passed
3220 Inappropriate MIME types, such as zipped files, are not filtered at all.
3221 (Again, only text-based types except plain text). Encrypted SSL data (from
3222 HTTPS servers) cannot be filtered either, since this would violate the
3223 integrity of the secure transaction. In some situations it might be
3224 necessary to protect certain text, like source code, from filtering by
3225 defining appropriate -filter exceptions.
3227 At this time, Privoxy cannot uncompress compressed documents. If you want
3228 filtering to work on all documents, even those that would normally be sent
3229 compressed, use the prevent-compression action in conjunction with filter.
3231 Filtering can achieve some of the same effects as the block action, i.e. it
3232 can be used to block ads and banners. But the mechanism works quite
3233 differently. One effective use, is to block ad banners based on their size
3234 (see below), since many of these seem to be somewhat standardized.
3236 Feedback with suggestions for new or improved filters is particularly
3239 The below list has only the names and a one-line description of each
3240 predefined filter. There are more verbose explanations of what these
3241 filters do in the filter file chapter.
3243 Example usage (with filters from the distribution default.filter file). See the
3244 Predefined Filters section for more explanation on each:
3246 +filter{js-annoyances} # Get rid of particularly annoying JavaScript abuse
3248 +filter{js-events} # Kill all JS event bindings (Radically destructive! Only for extra nasty sites)
3250 +filter{html-annoyances} # Get rid of particularly annoying HTML abuse
3252 +filter{content-cookies} # Kill cookies that come in the HTML or JS content
3254 +filter{refresh-tags} # Kill automatic refresh tags (for dial-on-demand setups)
3256 +filter{unsolicited-popups} # Disable only unsolicited pop-up windows
3258 +filter{all-popups} # Kill all popups in JavaScript and HTML
3260 +filter{img-reorder} # Reorder attributes in <img> tags to make the banners-by-* filters more effective
3262 +filter{banners-by-size} # Kill banners by size
3264 +filter{banners-by-link} # Kill banners by their links to known clicktrackers
3266 +filter{webbugs} # Squish WebBugs (1x1 invisible GIFs used for user tracking)
3268 +filter{tiny-textforms} # Extend those tiny textareas up to 40x80 and kill the hard wrap
3270 +filter{jumping-windows} # Prevent windows from resizing and moving themselves
3272 +filter{frameset-borders} # Give frames a border and make them resizeable
3274 +filter{demoronizer} # Fix MS's non-standard use of standard charsets
3276 +filter{shockwave-flash} # Kill embedded Shockwave Flash objects
3278 +filter{quicktime-kioskmode} # Make Quicktime movies savable
3280 +filter{fun} # Text replacements for subversive browsing fun!
3282 +filter{crude-parental} # Crude parental filtering (demo only)
3284 +filter{ie-exploits} # Disable some known Internet Explorer bug exploits
3286 -------------------------------------------------------------------------------
3288 8.5.13. filter-client-headers
3292 To apply filtering to the client's (browser's) headers
3296 By default, Privoxy's filters only apply to the document content itself.
3297 This will extend those filters to include the client's headers as well.
3309 Regular expressions can be used to filter headers as well. Check your
3310 filters closely before activating this action, as it can easily lead to
3313 These filters are applied to each header on its own, not to them all at
3314 once. This makes it easier to diagnose problems, but on the downside you
3315 can't write filters that only change header x if header y's value is z.
3317 The filters are used after the other header actions have finished and can
3318 use their output as input.
3320 Whenever possible one should specify ^, $, the whole header name and the
3321 colon, to make sure the filter doesn't cause havoc to other headers or the
3322 page itself. For example if you want to transform Galeon User-Agents to
3323 Firefox User-Agents you shouldn't use:
3325 s@Galeon/\d\.\d\.\d @@
3329 s@^(User-Agent:.*) Galeon/\d\.\d\.\d (Firefox/\d\.\d\.\d\.\d)$@$1 $2@
3331 Example usage (section):
3333 {+filter-client-headers +filter{test_filter}}
3334 problem-host.example.com
3337 -------------------------------------------------------------------------------
3339 8.5.14. filter-server-headers
3343 To apply filtering to the server's headers
3347 By default, Privoxy's filters only apply to the document content itself.
3348 This will extend those filters to include the server's headers as well.
3360 Similar to filter-client-headers, but works on the server instead. To
3361 filter both server and client, use both.
3363 As with filter-client-headers, check your filters before activating this
3364 action, as it can easily lead to broken requests.
3366 These filters are applied to each header on its own, not to them all at
3367 once. This makes it easier to diagnose problems, but on the downside you
3368 can't write filters that only change header x if header y's value is z.
3370 The filters are used after the other header actions have finished and can
3371 use their output as input.
3373 Remember too, whenever possible one should specify ^, $, the whole header
3374 name and the colon, to make sure the filter doesn't cause havoc to other
3375 headers or the page itself. See above for example.
3377 Example usage (section):
3379 {+filter-server-headers +filter{test_filter}}
3380 problem-host.example.com
3383 -------------------------------------------------------------------------------
3385 8.5.15. force-text-mode
3389 Force Privoxy to treat a document as if it was in some kind of text format.
3393 Declares a document as text, even if the "Content-Type:" isn't detected as
3406 As explained above, Privoxy tries to only filter files that are in some
3407 kind of text format. The same restrictions apply to content-type-overwrite.
3408 force-text-mode declares a document as text, without looking at the
3409 "Content-Type:" first.
3411 +-----------------------------------------------------------------+
3413 |-----------------------------------------------------------------|
3414 |Think twice before activating this action. Filtering binary data |
3415 |with regular expressions can cause file damage. |
3416 +-----------------------------------------------------------------+
3422 -------------------------------------------------------------------------------
3424 8.5.16. handle-as-empty-document
3428 Mark URLs that should be replaced by empty documents if they get blocked
3432 This action alone doesn't do anything noticeable. It just marks URLs. If
3433 the block action also applies, the presence or absence of this mark decides
3434 whether an HTML "blocked" page, or an empty document will be sent to the
3435 client as a substitute for the blocked content. The empty document isn't
3436 literally empty, but actually contains a single space.
3448 Some browsers complain about syntax errors if JavaScript documents are
3449 blocked with Privoxy's default HTML page; this option can be used to
3452 The content type for the empty document can be specified with
3453 content-type-overwrite{}, but usually this isn't necessary.
3457 # Block all documents on example.org that end with ".js",
3458 # but send an empty document instead of the usual HTML message.
3459 {+block +handle-as-empty-document}
3463 -------------------------------------------------------------------------------
3465 8.5.17. handle-as-image
3469 Mark URLs as belonging to images (so they'll be replaced by images if they
3470 do get blocked, rather than HTML pages)
3474 This action alone doesn't do anything noticeable. It just marks URLs as
3475 images. If the block action also applies, the presence or absence of this
3476 mark decides whether an HTML "blocked" page, or a replacement image (as
3477 determined by the set-image-blocker action) will be sent to the client as a
3478 substitute for the blocked content.
3490 The below generic example section is actually part of default.action. It
3491 marks all URLs with well-known image file name extensions as images and
3492 should be left intact.
3494 Users will probably only want to use the handle-as-image action in
3495 conjunction with block, to block sources of banners, whose URLs don't
3496 reflect the file type, like in the second example section.
3498 Note that you cannot treat HTML pages as images in most cases. For
3499 instance, (in-line) ad frames require an HTML page to be sent, or they
3500 won't display properly. Forcing handle-as-image in this situation will not
3501 replace the ad frame with an image, but lead to error messages.
3503 Example usage (sections):
3505 # Generic image extensions:
3508 /.*\.(gif|jpg|jpeg|png|bmp|ico)$
3510 # These don't look like images, but they're banners and should be
3511 # blocked as images:
3513 {+block +handle-as-image}
3514 some.nasty-banner-server.com/junk.cgi?output=trash
3516 # Banner source! Who cares if they also have non-image content?
3519 -------------------------------------------------------------------------------
3521 8.5.18. hide-accept-language
3525 Pretend to use different language settings.
3529 Deletes or replaces the "Accept-Language:" HTTP header in client requests.
3537 Keyword: "block", or any user defined value.
3541 Faking the browser's language settings can be useful to make a foreign
3542 User-Agent set with hide-user-agent more believable.
3544 However some sites with content in different languages check the
3545 "Accept-Language:" to decide which one to take by default. Sometimes it
3546 isn't possible to later switch to another language without changing the
3547 "Accept-Language:" header first.
3549 Therefore it's a good idea to either only change the "Accept-Language:"
3550 header to languages you understand, or to languages that aren't wide
3553 Before setting the "Accept-Language:" header to a rare language, you should
3554 consider that it helps to make your requests unique and thus easier to
3555 trace. If you don't plan to change this header frequently, you should stick
3556 to a common language.
3558 Example usage (section):
3560 # Pretend to use Canadian language settings.
3561 {+hide-accept-language{en-ca} \
3562 +hide-user-agent{Mozilla/5.0 (X11; U; OpenBSD i386; en-CA; rv:1.8.0.4) Gecko/20060628 Firefox/1.5.0.4} \
3566 -------------------------------------------------------------------------------
3568 8.5.19. hide-content-disposition
3572 Prevent download menus for content you prefer to view inside the browser.
3576 Deletes or replaces the "Content-Disposition:" HTTP header set by some
3585 Keyword: "block", or any user defined value.
3589 Some servers set the "Content-Disposition:" HTTP header for documents they
3590 assume you want to save locally before viewing them. The
3591 "Content-Disposition:" header contains the file name the browser is
3592 supposed to use by default.
3594 In most browsers that understand this header, it makes it impossible to
3595 just view the document, without downloading it first, even if it's just a
3596 simple text file or an image.
3598 Removing the "Content-Disposition:" header helps to prevent this annoyance,
3599 but some browsers additionally check the "Content-Type:" header, before
3600 they decide if they can display a document without saving it first. In
3601 these cases, you have to change this header as well, before the browser
3602 stops displaying download menus.
3604 It is also possible to change the server's file name suggestion to another
3605 one, but in most cases it isn't worth the time to set it up.
3609 # Disarm the download link in Sourceforge's patch tracker
3611 +content-type-overwrite {text/plain}\
3612 +hide-content-disposition {block} }
3613 .sourceforge.net/tracker/download.php
3615 -------------------------------------------------------------------------------
3617 8.5.20. hide-if-modified-since
3621 Prevent yet another way to track the user's steps between sessions.
3625 Deletes the "If-Modified-Since:" HTTP client header or modifies its value.
3633 Keyword: "block", or a user defined value that specifies a range of hours.
3637 Removing this header is useful for filter testing, where you want to force
3638 a real reload instead of getting status code "304", which would cause the
3639 browser to use a cached copy of the page.
3641 Instead of removing the header, hide-if-modified-since can also add or
3642 subtract a random amount of time to/from the header's value. You specify a
3643 range of minutes where the random factor should be chosen from and Privoxy
3644 does the rest. A negative value means subtracting, a positive value adding.
3646 Randomizing the value of the "If-Modified-Since:" makes sure it isn't used
3647 as a cookie replacement, but you will run into caching problems if the
3648 random range is too high.
3650 It is a good idea to only use a small negative value and let
3651 overwrite-last-modified handle the greater changes.
3653 It is also recommended to use this action together with
3654 crunch-if-none-match.
3656 Example usage (section):
3658 # Let the browser revalidate without being tracked across sessions
3659 {+hide-if-modified-since {-60}\
3660 +overwrite-last-modified {randomize}\
3661 +crunch-if-none-match}
3664 -------------------------------------------------------------------------------
3666 8.5.21. hide-forwarded-for-headers
3670 Improve privacy by hiding the true source of the request
3674 Deletes any existing "X-Forwarded-for:" HTTP header from client requests,
3675 and prevents adding a new one.
3687 It is fairly safe to leave this on.
3689 This action is scheduled for improvement: It should be able to generate
3690 forged "X-Forwarded-for:" headers using random IP addresses from a
3691 specified network, to make successive requests from the same client look
3692 like requests from a pool of different users sharing the same proxy.
3696 +hide-forwarded-for-headers
3698 -------------------------------------------------------------------------------
3700 8.5.22. hide-from-header
3704 Keep your (old and ill) browser from telling web servers your email address
3708 Deletes any existing "From:" HTTP header, or replaces it with the specified
3717 Keyword: "block", or any user defined value.
3721 The keyword "block" will completely remove the header (not to be confused
3722 with the block action).
3724 Alternately, you can specify any value you prefer to be sent to the web
3725 server. If you do, it is a matter of fairness not to use any address that
3726 is actually used by a real person.
3728 This action is rarely needed, as modern web browsers don't send "From:"
3733 +hide-from-header{block}
3737 +hide-from-header{spam-me-senseless@sittingduck.example.com}
3739 -------------------------------------------------------------------------------
3741 8.5.23. hide-referrer
3745 Conceal which link you followed to get to a particular site
3749 Deletes the "Referer:" (sic) HTTP header from the client request, or
3750 replaces it with a forged one.
3758 + "conditional-block" to delete the header completely if the host has
3761 + "block" to delete the header unconditionally.
3763 + "forge" to pretend to be coming from the homepage of the server we are
3766 + Any other string to set a user defined referrer.
3770 conditional-block is the only parameter, that isn't easily detected in the
3771 server's log file. If it blocks the referrer, the request will look like
3772 the visitor used a bookmark or typed in the address directly.
3774 Leaving the referrer unmodified for requests on the same host allows the
3775 server owner to see the visitor's "click path", but in most cases she could
3776 also get that information by comparing other parts of the log file: for
3777 example the User-Agent if it isn't a very common one, or the user's IP
3778 address if it doesn't change between different requests.
3780 Always blocking the referrer, or using a custom one, can lead to failures
3781 on servers that check the referrer before they answer any requests, in an
3782 attempt to prevent their valuable content from being embedded or linked to
3785 Both conditional-block and forge will work with referrer checks, as long as
3786 content and valid referring page are on the same host. Most of the time
3789 hide-referer is an alternate spelling of hide-referrer and the two can be
3790 can be freely substituted with each other. ("referrer" is the correct
3791 English spelling, however the HTTP specification has a bug - it requires it
3792 to be spelled as "referer".)
3796 +hide-referrer{forge}
3800 +hide-referrer{http://www.yahoo.com/}
3802 -------------------------------------------------------------------------------
3804 8.5.24. hide-user-agent
3808 Conceal your type of browser and client operating system
3812 Replaces the value of the "User-Agent:" HTTP header in client requests with
3813 the specified value.
3821 Any user-defined string.
3825 +-----------------------------------------------------------------+
3827 |-----------------------------------------------------------------|
3828 |This can lead to problems on web sites that depend on looking at |
3829 |this header in order to customize their content for different |
3830 |browsers (which, by the way, is NOT the right thing to do: good |
3831 |web sites work browser-independently). |
3832 +-----------------------------------------------------------------+
3834 Using this action in multi-user setups or wherever different types of
3835 browsers will access the same Privoxy is not recommended. In single-user,
3836 single-browser setups, you might use it to delete your OS version
3837 information from the headers, because it is an invitation to exploit known
3838 bugs for your OS. It is also occasionally useful to forge this in order to
3839 access sites that won't let you in otherwise (though there may be a good
3840 reason in some cases). Example of this: some MSN sites will not let Mozilla
3841 enter, yet forging to a Netscape 6.1 user-agent works just fine. (Must be
3842 just a silly MS goof, I'm sure :-).
3844 This action is scheduled for improvement.
3848 +hide-user-agent{Netscape 6.1 (X11; I; Linux 2.4.18 i686)}
3850 -------------------------------------------------------------------------------
3852 8.5.25. inspect-jpegs
3856 To protect against the MS buffer over-run in JPEG processing
3860 Protect against a known exploit
3872 See Microsoft Security Bulletin MS04-028. JPEG images are one of the most
3873 common image types found across the Internet. The exploit as described can
3874 allow execution of code on the target system, giving an attacker access to
3875 the system in question by merely planting an altered JPEG image, which
3876 would have no obvious indications of what lurks inside. This action
3877 prevents unwanted intrusion.
3883 -------------------------------------------------------------------------------
3889 Eliminate those annoying pop-up windows (deprecated)
3893 While loading the document, replace JavaScript code that opens pop-up
3894 windows with (syntactically neutral) dummy code on the fly.
3906 This action is basically a built-in, hardwired special-purpose filter
3907 action, but there are important differences: For kill-popups, the document
3908 need not be buffered, so it can be incrementally rendered while
3909 downloading. But kill-popups doesn't catch as many pop-ups as filter
3910 {all-popups} does and is not as smart as filter{unsolicited-popups} is.
3912 Think of it as a fast and efficient replacement for a filter that you can
3913 use if you don't want any filtering at all. Note that it doesn't make sense
3914 to combine it with any filter action, since as soon as one filter applies,
3915 the whole document needs to be buffered anyway, which destroys the
3916 advantage of the kill-popups action over its filter equivalent.
3918 Killing all pop-ups unconditionally is problematic. Many shops and banks
3919 rely on pop-ups to display forms, shopping carts etc, and the filter
3920 {unsolicited-popups} does a fairly good job of catching only the unwanted
3923 If the only kind of pop-ups that you want to kill are exit consoles (those
3924 really nasty windows that appear when you close an other one), you might
3925 want to use filter{js-annoyances} instead.
3931 -------------------------------------------------------------------------------
3933 8.5.27. limit-connect
3937 Prevent abuse of Privoxy as a TCP proxy relay or disable SSL for untrusted
3942 Specifies to which ports HTTP CONNECT requests are allowable.
3950 A comma-separated list of ports or port ranges (the latter using dashes,
3951 with the minimum defaulting to 0 and the maximum to 65K).
3955 By default, i.e. if no limit-connect action applies, Privoxy only allows
3956 HTTP CONNECT requests to port 443 (the standard, secure HTTPS port). Use
3957 limit-connect if more fine-grained control is desired for some or all
3960 The CONNECT methods exists in HTTP to allow access to secure websites
3961 ("https://" URLs) through proxies. It works very simply: the proxy connects
3962 to the server on the specified port, and then short-circuits its
3963 connections to the client and to the remote server. This can be a big
3964 security hole, since CONNECT-enabled proxies can be abused as TCP relays
3967 Privoxy relays HTTPS traffic without seeing the decoded content. Websites
3968 can leverage this limitation to circumvent Privoxy's filters. By specifying
3969 an invalid port range you can disable HTTPS entirely. If you plan to
3970 disable SSL by default, consider enabling
3971 treat-forbidden-connects-like-blocks as well, to be able to quickly create
3976 +limit-connect{443} # This is the default and need not be specified.
3977 +limit-connect{80,443} # Ports 80 and 443 are OK.
3978 +limit-connect{-3, 7, 20-100, 500-} # Ports less than 3, 7, 20 to 100 and above 500 are OK.
3979 +limit-connect{-} # All ports are OK
3980 +limit-connect{,} # No HTTPS/SSL traffic is allowed
3982 -------------------------------------------------------------------------------
3984 8.5.28. prevent-compression
3988 Ensure that servers send the content uncompressed, so it can be passed
3993 Removes the Accept-Encoding header which can be used to ask for compressed
4006 More and more websites send their content compressed by default, which is
4007 generally a good idea and saves bandwidth. But for the filter,
4008 deanimate-gifs and kill-popups actions to work, Privoxy needs access to the
4009 uncompressed data. Unfortunately, Privoxy can't yet(!) uncompress, filter,
4010 and re-compress the content on the fly. So if you want to ensure that all
4011 websites, including those that normally compress, can be filtered, you need
4014 This will slow down transfers from those websites, though. If you use any
4015 of the above-mentioned actions, you will typically want to use
4016 prevent-compression in conjunction with them.
4018 Note that some (rare) ill-configured sites don't handle requests for
4019 uncompressed documents correctly (they send an empty document body). If you
4020 use prevent-compression per default, you'll have to add exceptions for
4021 those sites. See the example for how to do that.
4023 Example usage (sections):
4027 {+prevent-compression}
4030 # Make exceptions for ill sites:
4032 {-prevent-compression}
4034 www.pclinuxonline.com
4036 -------------------------------------------------------------------------------
4038 8.5.29. overwrite-last-modified
4042 Prevent yet another way to track the user's steps between sessions.
4046 Deletes the "Last-Modified:" HTTP server header or modifies its value.
4054 One of the keywords: "block", "reset-to-request-time" and "randomize"
4058 Removing the "Last-Modified:" header is useful for filter testing, where
4059 you want to force a real reload instead of getting status code "304", which
4060 would cause the browser to reuse the old version of the page.
4062 The "randomize" option overwrites the value of the "Last-Modified:" header
4063 with a randomly chosen time between the original value and the current
4064 time. In theory the server could send each document with a different
4065 "Last-Modified:" header to track visits without using cookies. "Randomize"
4066 makes it impossible and the browser can still revalidate cached documents.
4068 "reset-to-request-time" overwrites the value of the "Last-Modified:" header
4069 with the current time. You could use this option together with
4070 hided-if-modified-since to further customize your random range.
4072 The preferred parameter here is "randomize". It is safe to use, as long as
4073 the time settings are more or less correct. If the server sets the
4074 "Last-Modified:" header to the time of the request, the random range
4075 becomes zero and the value stays the same. Therefore you should later
4076 randomize it a second time with hided-if-modified-since, just to be sure.
4078 It is also recommended to use this action together with
4079 crunch-if-none-match.
4083 # Let the browser revalidate without being tracked across sessions
4084 {+hide-if-modified-since {-60}\
4085 +overwrite-last-modified {randomize}\
4086 +crunch-if-none-match}
4089 -------------------------------------------------------------------------------
4095 Redirect requests to other sites.
4099 Convinces the browser that the requested document has been moved to another
4100 location and the browser should get it from there.
4112 This action is useful to replace whole documents with ones of your
4113 choosing. This can be used to enforce safe surfing, or just as a simple
4116 You can do the same by combining the actions block, handle-as-image and
4117 set-image-blocker{URL}. It doesn't sound right for non-image documents, and
4118 that's why this action was created.
4120 This action will be ignored if you use it together with block.
4124 # Replace example.com's style sheet with another one
4125 { +redirect{http://localhost/css-replacements/example.com.css} }
4126 example.com/stylesheet.css
4128 # Create a short, easy to remember nickname for a favorite site
4129 { +redirect{http://www.privoxy.org/user-manual/actions-file.html} }
4132 -------------------------------------------------------------------------------
4134 8.5.31. send-vanilla-wafer
4138 Feed log analysis scripts with useless data.
4142 Sends a cookie with each request stating that you do not accept any
4143 copyright on cookies sent to you, and asking the site operator not to track
4156 The vanilla wafer is a (relatively) unique header and could conceivably be
4159 This action is rarely used and not enabled in the default configuration.
4165 -------------------------------------------------------------------------------
4171 Send custom cookies or feed log analysis scripts with even more useless
4176 Sends a custom, user-defined cookie with each request.
4184 A string of the form "name=value".
4188 Being multi-valued, multiple instances of this action can apply to the same
4189 request, resulting in multiple cookies being sent.
4191 This action is rarely used and not enabled in the default configuration.
4193 Example usage (section):
4195 {+send-wafer{UsingPrivoxy=true}}
4196 my-internal-testing-server.void
4198 -------------------------------------------------------------------------------
4200 8.5.33. session-cookies-only
4204 Allow only temporary "session" cookies (for the current browser session
4209 Deletes the "expires" field from "Set-Cookie:" server headers. Most
4210 browsers will not store such cookies permanently and forget them in between
4223 This is less strict than crunch-incoming-cookies / crunch-outgoing-cookies
4224 and allows you to browse websites that insist or rely on setting cookies,
4225 without compromising your privacy too badly.
4227 Most browsers will not permanently store cookies that have been processed
4228 by session-cookies-only and will forget about them between sessions. This
4229 makes profiling cookies useless, but won't break sites which require
4230 cookies so that you can log in for transactions. This is generally turned
4231 on for all sites, and is the recommended setting.
4233 It makes no sense at all to use session-cookies-only together with
4234 crunch-incoming-cookies or crunch-outgoing-cookies. If you do, cookies will
4237 Note that it is up to the browser how it handles such cookies without an
4238 "expires" field. If you use an exotic browser, you might want to try it out
4241 This setting also has no effect on cookies that may have been stored
4242 previously by the browser before starting Privoxy. These would have to be
4245 Privoxy also uses the content-cookies filter to block some types of
4246 cookies. Content cookies are not effected by session-cookies-only.
4250 +session-cookies-only
4252 -------------------------------------------------------------------------------
4254 8.5.34. set-image-blocker
4258 Choose the replacement for blocked images
4262 This action alone doesn't do anything noticeable. If both block and
4263 handle-as-image also apply, i.e. if the request is to be blocked as an
4264 image, then the parameter of this action decides what will be sent as a
4273 + "pattern" to send a built-in checkerboard pattern image. The image is
4274 visually decent, scales very well, and makes it obvious where banners
4277 + "blank" to send a built-in transparent image. This makes banners
4278 disappear completely, but makes it hard to detect where Privoxy has
4279 blocked images on a given page and complicates troubleshooting if
4280 Privoxy has blocked innocent images, like navigation icons.
4282 + "target-url" to send a redirect to target-url. You can redirect to any
4283 image anywhere, even in your local filesystem via "file:///" URL. (But
4284 note that not all browsers support redirecting to a local file system).
4286 A good application of redirects is to use special Privoxy-built-in
4287 URLs, which send the built-in images, as target-url. This has the same
4288 visual effect as specifying "blank" or "pattern" in the first place,
4289 but enables your browser to cache the replacement image, instead of
4290 requesting it over and over again.
4294 The URLs for the built-in images are "http://config.privoxy.org/
4295 send-banner?type=type", where type is either "blank" or "pattern".
4297 There is a third (advanced) type, called "auto". It is NOT to be used in
4298 set-image-blocker, but meant for use from filters. Auto will select the
4299 type of image that would have applied to the referring page, had it been an
4306 +set-image-blocker{pattern}
4308 Redirect to the BSD devil:
4310 +set-image-blocker{http://www.freebsd.org/gifs/dae_up3.gif}
4312 Redirect to the built-in pattern for better caching:
4314 +set-image-blocker{http://config.privoxy.org/send-banner?type=pattern}
4316 -------------------------------------------------------------------------------
4318 8.5.35. treat-forbidden-connects-like-blocks
4322 Block forbidden connects with an easy to find error message.
4326 If this action is enabled, Privoxy no longer makes a difference between
4327 forbidden connects and ordinary blocks.
4339 By default Privoxy answers forbidden "Connect" requests with a short error
4340 message inside the headers. If the browser doesn't display headers (most
4341 don't), you just see an empty page.
4343 With this action enabled, Privoxy displays the message that is used for
4344 ordinary blocks instead. If you decide to make an exception for the page in
4345 question, you can do so by following the "See why" link.
4347 For "Connect" requests the clients tell Privoxy which host they are
4348 interested in, but not which document they plan to get later. As a result,
4349 the "Go there anyway" link becomes rather useless: it lets the client
4350 request the home page of the forbidden host through unencrypted HTTP, still
4351 using the port of the last request.
4353 If you previously configured Privoxy to do the request through a SSL
4354 tunnel, everything will work. Most likely you haven't and the server will
4355 respond with an error message because it is expecting HTTPS (SSL).
4359 +treat-forbidden-connects-like-blocks
4361 -------------------------------------------------------------------------------
4365 Note that many of these actions have the potential to cause a page to
4366 misbehave, possibly even not to display at all. There are many ways a site
4367 designer may choose to design his site, and what HTTP header content, and other
4368 criteria, he may depend on. There is no way to have hard and fast rules for all
4369 sites. See the Appendix for a brief example on troubleshooting actions.
4371 -------------------------------------------------------------------------------
4375 Custom "actions", known to Privoxy as "aliases", can be defined by combining
4376 other actions. These can in turn be invoked just like the built-in actions.
4377 Currently, an alias name can contain any character except space, tab, "=", "{"
4378 and "}", but we strongly recommend that you only use "a" to "z", "0" to "9",
4379 "+", and "-". Alias names are not case sensitive, and are not required to start
4380 with a "+" or "-" sign, since they are merely textually expanded.
4382 Aliases can be used throughout the actions file, but they must be defined in a
4383 special section at the top of the file! And there can only be one such section
4384 per actions file. Each actions file may have its own alias section, and the
4385 aliases defined in it are only visible within that file.
4387 There are two main reasons to use aliases: One is to save typing for frequently
4388 used combinations of actions, the other one is a gain in flexibility: If you
4389 decide once how you want to handle shops by defining an alias called "shop",
4390 you can later change your policy on shops in one place, and your changes will
4391 take effect everywhere in the actions file where the "shop" alias is used.
4392 Calling aliases by their purpose also makes your actions files more readable.
4394 Currently, there is one big drawback to using aliases, though: Privoxy's
4395 built-in web-based action file editor honors aliases when reading the actions
4396 files, but it expands them before writing. So the effects of your aliases are
4397 of course preserved, but the aliases themselves are lost when you edit sections
4398 that use aliases with it. This is likely to change in future versions of
4401 Now let's define some aliases...
4403 # Useful custom aliases we can use later.
4405 # Note the (required!) section header line and that this section
4406 # must be at the top of the actions file!
4410 # These aliases just save typing later:
4411 # (Note that some already use other aliases!)
4413 +crunch-all-cookies = +crunch-incoming-cookies +crunch-outgoing-cookies
4414 -crunch-all-cookies = -crunch-incoming-cookies -crunch-outgoing-cookies
4415 +block-as-image = +block +handle-as-image
4416 mercy-for-cookies = -crunch-all-cookies -session-cookies-only -filter{content-cookies}
4418 # These aliases define combinations of actions
4419 # that are useful for certain types of sites:
4421 fragile = -block -filter -crunch-all-cookies -fast-redirects -hide-referrer -kill-popups
4422 shop = -crunch-all-cookies -filter{all-popups} -kill-popups
4424 # Short names for other aliases, for really lazy people ;-)
4426 c0 = +crunch-all-cookies
4427 c1 = -crunch-all-cookies
4429 ...and put them to use. These sections would appear in the lower part of an
4430 actions file and define exceptions to the default actions (as specified further
4431 up for the "/" pattern):
4433 # These sites are either very complex or very keen on
4434 # user data and require minimal interference to work:
4437 .office.microsoft.com
4438 .windowsupdate.microsoft.com
4442 # Allow cookies (for setting and retrieving your customer data)
4446 .worldpay.com # for quietpc.com
4449 # These shops require pop-ups:
4451 {shop -kill-popups -filter{all-popups}}
4455 Aliases like "shop" and "fragile" are often used for "problem" sites that
4456 require some actions to be disabled in order to function properly.
4458 -------------------------------------------------------------------------------
4460 8.7. Actions Files Tutorial
4462 The above chapters have shown which actions files there are and how they are
4463 organized, how actions are specified and applied to URLs, how patterns work,
4464 and how to define and use aliases. Now, let's look at an example default.action
4465 and user.action file and see how all these pieces come together:
4467 -------------------------------------------------------------------------------
4469 8.7.1. default.action
4471 Every config file should start with a short comment stating its purpose:
4473 # Sample default.action file <ijbswa-developers@lists.sourceforge.net>
4475 Then, since this is the default.action file, the first section is a special
4476 section for internal use that you needn't change or worry about:
4478 ##########################################################################
4479 # Settings -- Don't change! For internal Privoxy use ONLY.
4480 ##########################################################################
4483 for-privoxy-version=3.0
4485 After that comes the (optional) alias section. We'll use the example section
4486 from the above chapter on aliases, that also explains why and how aliases are
4489 ##########################################################################
4491 ##########################################################################
4494 # These aliases just save typing later:
4495 # (Note that some already use other aliases!)
4497 +crunch-all-cookies = +crunch-incoming-cookies +crunch-outgoing-cookies
4498 -crunch-all-cookies = -crunch-incoming-cookies -crunch-outgoing-cookies
4499 +block-as-image = +block +handle-as-image
4500 mercy-for-cookies = -crunch-all-cookies -session-cookies-only -filter{content-cookies}
4502 # These aliases define combinations of actions
4503 # that are useful for certain types of sites:
4505 fragile = -block -filter -crunch-all-cookies -fast-redirects -hide-referrer -kill-popups
4506 shop = -crunch-all-cookies -filter{all-popups} -kill-popups
4508 Now come the regular sections, i.e. sets of actions, accompanied by URL
4509 patterns to which they apply. Remember all actions are disabled when matching
4510 starts, so we have to explicitly enable the ones we want.
4512 The first regular section is probably the most important. It has only one
4513 pattern, "/", but this pattern matches all URLs. Therefore, the set of actions
4514 used in this "default" section will be applied to all requests as a start. It
4515 can be partly or wholly overridden by later matches further down this file, or
4516 in user.action, but it will still be largely responsible for your overall
4517 browsing experience.
4519 Again, at the start of matching, all actions are disabled, so there is no real
4520 need to disable any actions here, but we will do that nonetheless, to have a
4521 complete listing for your reference. (Remember: a "+" preceding the action name
4522 enables the action, a "-" disables!). Also note how this long line has been
4523 made more readable by splitting it into multiple lines with line continuation.
4525 ##########################################################################
4526 # "Defaults" section:
4527 ##########################################################################
4531 -content-type-overwrite \
4532 -crunch-client-header \
4533 -crunch-if-none-match \
4534 -crunch-incoming-cookies \
4535 -crunch-server-header \
4536 -crunch-outgoing-cookies \
4538 -downgrade-http-version \
4539 +fast-redirects{check-decoded-url} \
4540 +filter{js-annoyances} \
4541 -filter{js-events} \
4542 +filter{html-annoyances} \
4543 -filter{content-cookies} \
4544 +filter{refresh-tags} \
4545 +filter{unsolicited-popups} \
4546 -filter{all-popups} \
4547 +filter{img-reorder} \
4548 +filter{banners-by-size} \
4549 -filter{banners-by-link} \
4551 -filter{tiny-textforms} \
4552 +filter{jumping-windows} \
4553 -filter{frameset-borders} \
4554 -filter{demoronizer} \
4555 -filter{shockwave-flash} \
4556 -filter{quicktime-kioskmode} \
4558 -filter{crude-parental} \
4559 +filter{ie-exploits} \
4560 -filter-client-headers \
4561 -filter-server-headers \
4563 -handle-as-empty-document \
4565 -hide-accept-language \
4566 -hide-content-disposition \
4567 -hide-if-modified-since \
4568 +hide-forwarded-for-headers \
4569 +hide-from-header{block} \
4570 +hide-referrer{forge} \
4575 +prevent-compression \
4576 -overwrite-last-modified \
4578 -send-vanilla-wafer \
4580 +session-cookies-only \
4581 +set-image-blocker{pattern} \
4582 -treat-forbidden-connects-like-blocks \
4584 / # forward slash will match *all* potential URL patterns.
4586 The default behavior is now set. Note that some actions, like not hiding the
4587 user agent, are part of a "general policy" that applies universally and won't
4588 get any exceptions defined later. Other choices, like not blocking (which is
4589 understandably the default!) need exceptions, i.e. we need to specify
4590 explicitly what we want to block in later sections.
4592 The first of our specialized sections is concerned with "fragile" sites, i.e.
4593 sites that require minimum interference, because they are either very complex
4594 or very keen on tracking you (and have mechanisms in place that make them
4595 unusable for people who avoid being tracked). We will simply use our
4596 pre-defined fragile alias instead of stating the list of actions explicitly:
4598 ##########################################################################
4599 # Exceptions for sites that'll break under the default action set:
4600 ##########################################################################
4602 # "Fragile" Use a minimum set of actions for these sites (see alias above):
4605 .office.microsoft.com # surprise, surprise!
4606 .windowsupdate.microsoft.com
4608 Shopping sites are not as fragile, but they typically require cookies to log
4609 in, and pop-up windows for shopping carts or item details. Again, we'll use a
4616 .worldpay.com # for quietpc.com
4620 The fast-redirects action, which we enabled per default above, breaks some
4621 sites. So disable it for popular sites where we know it misbehaves:
4627 .altavista.com/.*(like|url|link):http
4628 .altavista.com/trans.*urltext=http
4631 It is important that Privoxy knows which URLs belong to images, so that if they
4632 are to be blocked, a substitute image can be sent, rather than an HTML page.
4633 Contacting the remote site to find out is not an option, since it would destroy
4634 the loading time advantage of banner blocking, and it would feed the
4635 advertisers (in terms of money and information). We can mark any URL as an
4636 image with the handle-as-image action, and marking all URLs that end in a known
4637 image file extension is a good start:
4639 ##########################################################################
4641 ##########################################################################
4643 # Define which file types will be treated as images, in case they get
4644 # blocked further down this file:
4646 { +handle-as-image }
4647 /.*\.(gif|jpe?g|png|bmp|ico)$
4649 And then there are known banner sources. They often use scripts to generate the
4650 banners, so it won't be visible from the URL that the request is for an image.
4651 Hence we block them and mark them as images in one go, with the help of our
4652 +block-as-image alias defined above. (We could of course just as well use +
4653 block +handle-as-image here.) Remember that the type of the replacement image
4654 is chosen by the set-image-blocker action. Since all URLs have matched the
4655 default section with its +set-image-blocker{pattern} action before, it still
4656 applies and needn't be repeated:
4658 # Known ad generators:
4663 .ad.*.doubleclick.net
4664 .a.yimg.com/(?:(?!/i/).)*$
4665 .a[0-9].yimg.com/(?:(?!/i/).)*$
4670 One of the most important jobs of Privoxy is to block banners. A huge bunch of
4671 them can be "blocked" by the filter{banners-by-size} action, which we enabled
4672 above, and which deletes the references to banner images from the pages while
4673 they are loaded, so the browser doesn't request them anymore, and hence they
4674 don't need to be blocked here. But this naturally doesn't catch all banners,
4675 and some people choose not to use filters, so we need a comprehensive list of
4676 patterns for banner URLs here, and apply the block action to them.
4678 First comes a bunch of generic patterns, which do most of the work, by matching
4679 typical domain and path name components of banners. Then comes a list of
4680 individual patterns for specific sites, which is omitted here to keep the
4683 ##########################################################################
4684 # Block these fine banners:
4685 ##########################################################################
4694 /.*count(er)?\.(pl|cgi|exe|dll|asp|php[34]?)
4695 /(?:.*/)?(publicite|werbung|rekla(ma|me|am)|annonse|maino(kset|nta|s)?)/
4697 # Site-specific patterns (abbreviated):
4701 You wouldn't believe how many advertisers actually call their banner servers
4702 ads.company.com, or call the directory in which the banners are stored simply
4703 "banners". So the above generic patterns are surprisingly effective.
4705 But being very generic, they necessarily also catch URLs that we don't want to
4706 block. The pattern .*ads. e.g. catches "nasty-ads.nasty-corp.com" as intended,
4707 but also "downloads.sourcefroge.net" or "adsl.some-provider.net." So here come
4708 some well-known exceptions to the +block section above.
4710 Note that these are exceptions to exceptions from the default! Consider the URL
4711 "downloads.sourcefroge.net": Initially, all actions are deactivated, so it
4712 wouldn't get blocked. Then comes the defaults section, which matches the URL,
4713 but just deactivates the block action once again. Then it matches .*ads., an
4714 exception to the general non-blocking policy, and suddenly +block applies. And
4715 now, it'll match .*loads., where -block applies, so (unless it matches again
4716 further down) it ends up with no block action applying.
4718 ##########################################################################
4719 # Save some innocent victims of the above generic block patterns:
4720 ##########################################################################
4725 adv[io]*. # (for advogato.org and advice.*)
4726 adsl. # (has nothing to do with ads)
4727 ad[ud]*. # (adult.* and add.*)
4728 .edu # (universities don't host banners (yet!))
4729 .*loads. # (downloads, uploads etc)
4737 www.globalintersec.com/adv # (adv = advanced)
4738 www.ugu.com/sui/ugu/adv
4740 Filtering source code can have nasty side effects, so make an exception for our
4741 friends at sourceforge.net, and all paths with "cvs" in them. Note that -filter
4742 disables all filters in one fell swoop!
4744 # Don't filter code!
4750 The actual default.action is of course much more comprehensive, but we hope
4751 this example made clear how it works.
4753 -------------------------------------------------------------------------------
4757 So far we are painting with a broad brush by setting general policies, which
4758 would be a reasonable starting point for many people. Now, you might want to be
4759 more specific and have customized rules that are more suitable to your personal
4760 habits and preferences. These would be for narrowly defined situations like
4761 your ISP or your bank, and should be placed in user.action, which is parsed
4762 after all other actions files and hence has the last word, over-riding any
4763 previously defined actions. user.action is also a safe place for your personal
4764 settings, since default.action is actively maintained by the Privoxy developers
4765 and you'll probably want to install updated versions from time to time.
4767 So let's look at a few examples of things that one might typically do in
4770 # My user.action file. <fred@foobar.com>
4772 As aliases are local to the actions file that they are defined in, you can't
4773 use the ones from default.action, unless you repeat them here:
4775 # Aliases are local to the file they are defined in.
4776 # (Re-)define aliases for this file:
4780 # These aliases just save typing later, and the alias names should
4781 # be self explanatory.
4783 +crunch-all-cookies = +crunch-incoming-cookies +crunch-outgoing-cookies
4784 -crunch-all-cookies = -crunch-incoming-cookies -crunch-outgoing-cookies
4785 allow-all-cookies = -crunch-all-cookies -session-cookies-only
4786 allow-popups = -filter{all-popups} -kill-popups
4787 +block-as-image = +block +handle-as-image
4788 -block-as-image = -block
4790 # These aliases define combinations of actions that are useful for
4791 # certain types of sites:
4793 fragile = -block -crunch-all-cookies -filter -fast-redirects -hide-referrer -kill-popups
4794 shop = -crunch-all-cookies allow-popups
4796 # Allow ads for selected useful free sites:
4798 allow-ads = -block -filter{banners-by-size} -filter{banners-by-link}
4800 # Alias for specific file types that are text, but might have conflicting
4801 # MIME types. We want the browser to force these to be text documents.
4802 handle-as-text = -filter +-content-type-overwrite{text/plain} +-force-text-mode -hide-content-disposition
4806 Say you have accounts on some sites that you visit regularly, and you don't
4807 want to have to log in manually each time. So you'd like to allow persistent
4808 cookies for these sites. The allow-all-cookies alias defined above does exactly
4809 that, i.e. it disables crunching of cookies in any direction, and the
4810 processing of cookies to make them only temporary.
4812 { allow-all-cookies }
4818 Your bank is allergic to some filter, but you don't know which, so you disable
4822 .your-home-banking-site.com
4824 Some file types you may not want to filter for various reasons:
4826 # Technical documentation is likely to contain strings that might
4827 # erroneously get altered by the JavaScript-oriented filters:
4832 # And this stupid host sends streaming video with a wrong MIME type,
4833 # so that Privoxy thinks it is getting HTML and starts filtering:
4835 stupid-server.example.com/
4837 Example of a simple block action. Say you've seen an ad on your favourite page
4838 on example.com that you want to get rid of. You have right-clicked the image,
4839 selected "copy image location" and pasted the URL below while removing the
4840 leading http://, into a { +block } section. Note that { +handle-as-image } need
4841 not be specified, since all URLs ending in .gif will be tagged as images by the
4842 general rules as set in default.action anyway:
4845 www.example.com/nasty-ads/sponsor.gif
4846 another.popular.site.net/more/junk/here/
4848 The URLs of dynamically generated banners, especially from large banner farms,
4849 often don't use the well-known image file name extensions, which makes it
4850 impossible for Privoxy to guess the file type just by looking at the URL. You
4851 can use the +block-as-image alias defined above for these cases. Note that
4852 objects which match this rule but then turn out NOT to be an image are
4853 typically rendered as a "broken image" icon by the browser. Use cautiously.
4861 Now you noticed that the default configuration breaks Forbes Magazine, but you
4862 were too lazy to find out which action is the culprit, and you were again too
4863 lazy to give feedback, so you just used the fragile alias on the site, and --
4864 whoa! -- it worked. The fragile aliases disables those actions that are most
4865 likely to break a site. Also, good for testing purposes to see if it is Privoxy
4866 that is causing the problem or not. We later find other regular sites that
4867 misbehave, and add those to our personalized list of troublemakers:
4874 You like the "fun" text replacements in default.filter, but it is disabled in
4875 the distributed actions file. (My colleagues on the team just don't have a
4876 sense of humour, that's why! ;-). So you'd like to turn it on in your private,
4877 update-safe config, once and for all:
4882 Note that the above is not really a good idea: There are exceptions to the
4883 filters in default.action for things that really shouldn't be filtered, like
4884 code on CVS->Web interfaces. Since user.action has the last word, these
4885 exceptions won't be valid for the "fun" filtering specified here.
4887 You might also worry about how your favourite free websites are funded, and
4888 find that they rely on displaying banner advertisements to survive. So you
4889 might want to specifically allow banners for those sites that you feel provide
4897 Note that allow-ads has been aliased to -block, -filter{banners-by-size}, and -
4898 filter{banners-by-link} above.
4900 Invoke another alias here to force an over-ride of the MIME type application/
4901 x-sh which typically would open a download type dialog. In my case, I want to
4902 look at the shell script, and then I can save it should I choose to.
4907 user.action is generally the best place to define exceptions and additions to
4908 the default policies of default.action. Some actions are safe to have their
4909 default policies set here though. So let's set a default policy to have a
4910 "blank" image as opposed to the checkerboard pattern for ALL sites. "/" of
4911 course matches all URL paths and patterns:
4913 { +set-image-blocker{blank} }
4916 -------------------------------------------------------------------------------
4920 On-the-fly text substitutions that can be invoked through the filter action
4921 need to be defined in a "filter file". Once defined, they can then be invoked
4922 as an "action". Multiple filter files can be defined through the filterfile
4923 config directive. The filters as supplied by the developers will be found in
4924 default.filter. It is recommended that any locally defined or modified filters
4925 go in a separately defined file such as user.filter.
4927 Typical reasons for doing these kinds of substitutions are to eliminate common
4928 annoyances in HTML and JavaScript, such as pop-up windows, exit consoles,
4929 crippled windows without navigation tools, the infamous <BLINK> tag etc, to
4930 suppress images with certain width and height attributes (standard banner sizes
4931 or web-bugs), or just to have fun. The possibilities are endless.
4933 Filtering works on any text-based document type, including HTML, JavaScript,
4934 CSS etc. (all text/* MIME types, except text/plain). Substitutions are made at
4935 the source level, so if you want to "roll your own" filters, you should first
4936 be familiar with HTML syntax, and, of course, regular expressions. By default,
4937 filters are only applied to the raw document content, but can be extended to
4938 the HTTP headers with the supplemental actions: filter-client-headers and
4939 filter-server-headers.
4941 Just like the actions files, the filter file is organized in sections, which
4942 are called filters here. Each filter consists of a heading line, that starts
4943 with the keyword FILTER:, followed by the filter's name, and a short (one line)
4944 description of what it does. Below that line come the jobs, i.e. lines that
4945 define the actual text substitutions. By convention, the name of a filter
4946 should describe what the filter eliminates. The comment is used in the
4947 web-based user interface.
4949 Once a filter called name has been defined in the filter file, it can be
4950 invoked by using an action of the form +filter{name} in any actions file.
4952 A filter header line for a filter called "foo" could look like this:
4954 FILTER: foo Replace all "foo" with "bar"
4956 Below that line, and up to the next header line, come the jobs that define what
4957 text replacements the filter executes. They are specified in a syntax that
4958 imitates Perl's s/// operator. If you are familiar with Perl, you will find
4959 this to be quite intuitive, and may want to look at the PCRS documentation for
4960 the subtle differences to Perl behaviour. Most notably, the non-standard option
4961 letter U is supported, which turns the default to ungreedy matching.
4963 If you are new to "Regular Expressions", you might want to take a look at the
4964 Appendix on regular expressions, and see the Perl manual for the s///
4965 operator's syntax and Perl-style regular expressions in general. The below
4966 examples might also help to get you started.
4968 -------------------------------------------------------------------------------
4970 9.1. Filter File Tutorial
4972 Now, let's complete our "foo" filter. We have already defined the heading, but
4973 the jobs are still missing. Since all it does is to replace "foo" with "bar",
4974 there is only one (trivial) job needed:
4978 But wait! Didn't the comment say that all occurrences of "foo" should be
4979 replaced? Our current job will only take care of the first "foo" on each page.
4980 For global substitution, we'll need to add the g option:
4984 Our complete filter now looks like this:
4986 FILTER: foo Replace all "foo" with "bar"
4989 Let's look at some real filters for more interesting examples. Here you see a
4990 filter that protects against some common annoyances that arise from JavaScript
4991 abuse. Let's look at its jobs one after the other:
4993 FILTER: js-annoyances Get rid of particularly annoying JavaScript abuse
4995 # Get rid of JavaScript referrer tracking. Test page: http://www.randomoddness.com/untitled.htm
4997 s|(<script.*)document\.referrer(.*</script>)|$1"Not Your Business!"$2|Usg
4999 Following the header line and a comment, you see the job. Note that it uses |
5000 as the delimiter instead of /, because the pattern contains a forward slash,
5001 which would otherwise have to be escaped by a backslash (\).
5003 Now, let's examine the pattern: it starts with the text <script.* enclosed in
5004 parentheses. Since the dot matches any character, and * means: "Match an
5005 arbitrary number of the element left of myself", this matches "<script",
5006 followed by any text, i.e. it matches the whole page, from the start of the
5009 That's more than we want, but the pattern continues: document\.referrer matches
5010 only the exact string "document.referrer". The dot needed to be escaped, i.e.
5011 preceded by a backslash, to take away its special meaning as a joker, and make
5012 it just a regular dot. So far, the meaning is: Match from the start of the
5013 first <script> tag in a the page, up to, and including, the text
5014 "document.referrer", if both are present in the page (and appear in that
5017 But there's still more pattern to go. The next element, again enclosed in
5018 parentheses, is .*</script>. You already know what .* means, so the whole
5019 pattern translates to: Match from the start of the first <script> tag in a page
5020 to the end of the last <script> tag, provided that the text "document.referrer"
5021 appears somewhere in between.
5023 This is still not the whole story, since we have ignored the options and the
5024 parentheses: The portions of the page matched by sub-patterns that are enclosed
5025 in parentheses, will be remembered and be available through the variables $1,
5026 $2, ... in the substitute. The U option switches to ungreedy matching, which
5027 means that the first .* in the pattern will only "eat up" all text in between "
5028 <script" and the first occurrence of "document.referrer", and that the second .
5029 * will only span the text up to the first "</script>" tag. Furthermore, the s
5030 option says that the match may span multiple lines in the page, and the g
5031 option again means that the substitution is global.
5033 So, to summarize, the pattern means: Match all scripts that contain the text
5034 "document.referrer". Remember the parts of the script from (and including) the
5035 start tag up to (and excluding) the string "document.referrer" as $1, and the
5036 part following that string, up to and including the closing tag, as $2.
5038 Now the pattern is deciphered, but wasn't this about substituting things? So
5039 lets look at the substitute: $1"Not Your Business!"$2 is easy to read: The text
5040 remembered as $1, followed by "Not Your Business!" (including the quotation
5041 marks!), followed by the text remembered as $2. This produces an exact copy of
5042 the original string, with the middle part (the "document.referrer") replaced by
5043 "Not Your Business!".
5045 The whole job now reads: Replace "document.referrer" by "Not Your Business!"
5046 wherever it appears inside a <script> tag. Note that this job won't break
5047 JavaScript syntax, since both the original and the replacement are
5048 syntactically valid string objects. The script just won't have access to the
5049 referrer information anymore.
5051 We'll show you two other jobs from the JavaScript taming department, but this
5052 time only point out the constructs of special interest:
5054 # The status bar is for displaying link targets, not pointless blahblah
5056 s/window\.status\s*=\s*(['"]).*?\1/dUmMy=1/ig
5058 \s stands for whitespace characters (space, tab, newline, carriage return, form
5059 feed), so that \s* means: "zero or more whitespace". The ? in .*? makes this
5060 matching of arbitrary text ungreedy. (Note that the U option is not set). The
5061 ['"] construct means: "a single or a double quote". Finally, \1 is a
5062 back-reference to the first parenthesis just like $1 above, with the difference
5063 that in the pattern, a backslash indicates a back-reference, whereas in the
5064 substitute, it's the dollar.
5066 So what does this job do? It replaces assignments of single- or double-quoted
5067 strings to the "window.status" object with a dummy assignment (using a variable
5068 name that is hopefully odd enough not to conflict with real variables in
5069 scripts). Thus, it catches many cases where e.g. pointless descriptions are
5070 displayed in the status bar instead of the link target when you move your mouse
5073 # Kill OnUnload popups. Yummy. Test: http://www.zdnet.com/zdsubs/yahoo/tree/yfs.html
5075 s/(<body [^>]*)onunload(.*>)/$1never$2/iU
5077 Including the OnUnload event binding in the HTML DOM was a CRIME. When I close
5078 a browser window, I want it to close and die. Basta. This job replaces the
5079 "onunload" attribute in "<body>" tags with the dummy word never. Note that the
5080 i option makes the pattern matching case-insensitive. Also note that ungreedy
5081 matching alone doesn't always guarantee a minimal match: In the first
5082 parenthesis, we had to use [^>]* instead of .* to prevent the match from
5083 exceeding the <body> tag if it doesn't contain "OnUnload", but the page's
5086 The last example is from the fun department:
5088 FILTER: fun Fun text replacements
5090 # Spice the daily news:
5092 s/microsoft(?!\.com)/MicroSuck/ig
5094 Note the (?!\.com) part (a so-called negative lookahead) in the job's pattern,
5095 which means: Don't match, if the string ".com" appears directly following
5096 "microsoft" in the page. This prevents links to microsoft.com from being
5097 trashed, while still replacing the word everywhere else.
5099 # Buzzword Bingo (example for extended regex syntax)
5101 s* industry[ -]leading \
5103 | customer[ -]focused \
5104 | market[ -]driven \
5105 | award[ -]winning # Comments are OK, too! \
5106 | high[ -]performance \
5107 | solutions[ -]based \
5111 *<font color="red"><b>BINGO!</b></font> \
5114 The x option in this job turns on extended syntax, and allows for e.g. the
5115 liberal use of (non-interpreted!) whitespace for nicer formatting.
5119 -------------------------------------------------------------------------------
5121 9.2. The Pre-defined Filters
5123 The distribution default.filter file contains a selection of pre-defined
5124 filters for your convenience:
5128 The purpose of this filter is to get rid of particularly annoying
5129 JavaScript abuse. To that end, it
5131 + replaces JavaScript references to the browser's referrer information
5132 with the string "Not Your Business!". This compliments the
5133 hide-referrer action on the content level.
5135 + removes the bindings to the DOM's unload event which we feel has no
5136 right to exist and is responsible for most "exit consoles", i.e. nasty
5137 windows that pop up when you close another one.
5139 + removes code that causes new windows to be opened with undesired
5140 properties, such as being full-screen, non-resizeable, without
5141 location, status or menu bar etc.
5145 This is a very radical measure. It removes virtually all JavaScript event
5146 bindings, which means that scripts can not react to user actions such as
5147 mouse movements or clicks, window resizing etc, anymore.
5149 We strongly discourage using this filter as a default since it breaks many
5150 legitimate scripts. It is meant for use only on extra-nasty sites (should
5151 you really need to go there).
5155 This filter will undo many common instances of HTML based abuse.
5157 The BLINK and MARQUEE tags are neutralized (yeah baby!), and browser
5158 windows will be created as resizeable (as of course they should be!), and
5159 will have location, scroll and menu bars -- even if specified otherwise.
5163 Most cookies are set in the HTTP dialog, where they can be intercepted by
5164 the crunch-incoming-cookies and crunch-outgoing-cookies actions. But web
5165 sites increasingly make use of HTML meta tags and JavaScript to sneak
5166 cookies to the browser on the content level.
5168 This filter disables HTML and JavaScript code that reads or sets cookies.
5169 Use it wherever you would also use the cookie crunch actions.
5173 Disable any refresh tags if the interval is greater than nine seconds (so
5174 that redirections done via refresh tags are not destroyed). This is useful
5175 for dial-on-demand setups, or for those who find this HTML feature
5180 This filter attempts to prevent only "unsolicited" pop-up windows from
5181 opening, yet still allow pop-up windows that the user has explicitly chosen
5182 to open. It was added in version 3.0.1, as an improvement over earlier such
5185 Technical note: The filter works by redefining the window.open JavaScript
5186 function to a dummy function during the loading and rendering phase of each
5187 HTML page access, and restoring the function afterward.
5191 Attempt to prevent all pop-up windows from opening. Note this should be
5192 used with more discretion than the above, since it is more likely to break
5193 some sites that require pop-ups for normal usage. Use with caution.
5197 This is a helper filter that has no value if used alone. It makes the
5198 banners-by-size and banners-by-link (see below) filters more effective and
5199 should be enabled together with them.
5203 This filter removes image tags purely based on what size they are.
5204 Fortunately for us, many ads and banner images tend to conform to certain
5205 standardized sizes, which makes this filter quite effective for ad
5208 Occasionally this filter will cause false positives on images that are not
5209 ads, but just happen to be of one of the standard banner sizes.
5213 This is an experimental filter that attempts to kill any banners if their
5214 URLs seem to point to known or suspected click trackers. It is currently
5215 not of much value and is not recommended for use by default.
5219 Webbugs are small, invisible images (technically 1X1 GIF images), that are
5220 used to track users across websites, and collect information on them. As an
5221 HTML page is loaded by the browser, an embedded image tag causes the
5222 browser to contact a third-party site, disclosing the tracking information
5223 through the requested URL and/or cookies for that third-party domain,
5224 without the use ever becoming aware of the interaction with the third-party
5225 site. HTML-ized spam also uses a similar technique to verify email
5228 This filter removes the HTML code that loads such "webbugs".
5232 A rather special-purpose filter that can be used to enlarge textareas
5233 (those multi-line text boxes in web forms) and turn off hard word wrap in
5234 them. It was written for the sourceforge.net tracker system where such
5235 boxes are a nuisance, but it can be handy on other sites, too.
5237 It is not recommended to use this filter as a default.
5241 Many consider windows that move, or resize themselves to be abusive. This
5242 filter neutralizes the related JavaScript code. Note that some sites might
5243 not display or behave as intended when using this filter.
5247 Some web designers seem to assume that everyone in the world will view
5248 their web sites using the same browser brand and version, screen resolution
5249 etc, because only that assumption could explain why they'd use static frame
5250 sizes, yet prevent their frames from being resized by the user, should they
5251 be too small to show their whole content.
5253 This filter removes the related HTML code. It should only be applied to
5254 sites which need it.
5258 Many Microsoft products that generate HTML use non-standard extensions
5259 (read: violations) of the ISO 8859-1 aka Latin-1 character set. This can
5260 cause those HTML documents to display with errors on standard-compliant
5263 This filter translates the MS-only characters into Latin-1 equivalents. It
5264 is not necessary when using MS products, and will cause corruption of all
5265 documents that use 8-bit character sets other than Latin-1. It's mostly
5266 worthwhile for Europeans on non-MS platforms, if weird garbage characters
5267 sometimes appear on some pages, or user agents that don't correct for this
5272 A filter for shockwave haters. As the name suggests, this filter strips
5273 code out of web pages that is used to embed shockwave flash objects.
5277 Change HTML code that embeds Quicktime objects so that kioskmode, which
5278 prevents saving, is disabled.
5282 Text replacements for subversive browsing fun. Make fun of your favorite
5283 Monopolist or play buzzword bingo.
5287 A demonstration-only filter that shows how Privoxy can be used to delete
5288 web content on a keyword basis.
5292 A collection of text replacements to disable malicious HTML and JavaScript
5293 code that exploits known security holes in Internet Explorer.
5295 Presently, it only protects against Nimda and a cross-site scripting bug,
5296 and would need active maintenance to provide more substantial protection.
5300 Some web sites have very specific problems, the cure for which doesn't
5301 apply anywhere else, or could even cause damage on other sites.
5303 This is a collection of such site-specific cures which should only be
5304 applied to the sites they were intended for, which is what the supplied
5305 default.action file does. Users shouldn't need to change anything regarding
5308 -------------------------------------------------------------------------------
5310 10. Privoxy's Template Files
5312 All Privoxy built-in pages, i.e. error pages such as the "404 - No Such Domain"
5313 error page, the "BLOCKED" page and all pages of its web-based user interface,
5314 are generated from templates. (Privoxy must be running for the above links to
5317 These templates are stored in a subdirectory of the configuration directory
5318 called templates. On Unixish platforms, this is typically /etc/privoxy/
5321 The templates are basically normal HTML files, but with place-holders (called
5322 symbols or exports), which Privoxy fills at run time. You can edit the
5323 templates with a normal text editor, should you want to customize them. (Not
5324 recommended for the casual user). Note that just like in configuration files,
5325 lines starting with # are ignored when the templates are filled in.
5327 The place-holders are of the form @name@, and you will find a list of available
5328 symbols, which vary from template to template, in the comments at the start of
5329 each file. Note that these comments are not always accurate, and that it's
5330 probably best to look at the existing HTML code to find out which symbols are
5331 supported and what they are filled in with.
5333 A special application of this substitution mechanism is to make whole blocks of
5334 HTML code disappear when a specific symbol is set. We use this for many
5335 purposes, one of them being to include the beta warning in all our user
5336 interface (CGI) pages when Privoxy is in an alpha or beta development stage:
5338 <!-- @if-unstable-start -->
5340 ... beta warning HTML code goes here ...
5342 <!-- if-unstable-end@ -->
5344 If the "unstable" symbol is set, everything in between and including
5345 @if-unstable-start and if-unstable-end@ will disappear, leaving nothing but an
5350 There's also an if-then-else construct and an #include mechanism, but you'll
5351 sure find out if you are inclined to edit the templates ;-)
5353 All templates refer to a style located at http://config.privoxy.org/
5354 send-stylesheet. This is, of course, locally served by Privoxy and the source
5355 for it can be found and edited in the cgi-style.css template.
5357 -------------------------------------------------------------------------------
5359 11. Contacting the Developers, Bug Reporting and Feature Requests
5361 We value your feedback. In fact, we rely on it to improve Privoxy and its
5362 configuration. However, please note the following hints, so we can provide you
5363 with the best support:
5365 -------------------------------------------------------------------------------
5369 For casual users, our support forum at SourceForge is probably best suited:
5370 http://sourceforge.net/tracker/?group_id=11118&atid=211118
5372 All users are of course welcome to discuss their issues on the users mailing
5373 list, where the developers also hang around.
5375 -------------------------------------------------------------------------------
5377 11.2. Reporting Problems
5379 "Problems" for our purposes, come in two forms:
5381 * Configuration issues, such as ads that slip through, or sites that don't
5382 function properly due to one Privoxy "action" or another being turned "on".
5384 * "Bugs" in the programming code that makes up Privoxy, such as that might
5387 -------------------------------------------------------------------------------
5389 11.2.1. Reporting Ads or Other Configuration Problems
5391 Please send feedback on ads that slipped through, innocent images that were
5392 blocked, sites that don't work properly, and other configuration related
5393 problem of default.action file, to http://sourceforge.net/tracker/?group_id=
5394 11118&atid=460288, the Actions File Tracker.
5396 New, improved default.action files may occasionally be made available based on
5397 your feedback. These will be announced on the ijbswa-announce list and
5398 available from our the files section of our project page.
5400 -------------------------------------------------------------------------------
5402 11.2.2. Reporting Bugs
5404 Please report all bugs only through our bug tracker: http://sourceforge.net/
5405 tracker/?group_id=11118&atid=111118.
5407 Before doing so, please make sure that the bug has not already been submitted
5408 and observe the additional hints at the top of the submit form. If already
5409 submitted, please feel free to add any info to the original report that might
5410 help to solve the issue.
5412 Please try to verify that it is a Privoxy bug, and not a browser or site bug
5413 first. If unsure, try toggling off Privoxy, and see if the problem persists. If
5414 you are using your own custom configuration, please try the stock configs to
5415 see if the problem is configuration related.
5417 If not using the latest version, the bug may have been found and fixed in the
5418 meantime. We would appreciate if you could take the time to upgrade to the
5419 latest version (or even the latest CVS snapshot) and verify your bug.
5421 Please be sure to provide the following information:
5423 * The exact Privoxy version of the proxy software (if you got the source from
5424 CVS, please also provide the source code revisions as shown in http://
5425 config.privoxy.org/show-version).
5427 * The operating system and versions you run Privoxy on, (e.g. Windows XP
5428 SP2), if you are using some kind of Unix flavour, sending the output of
5429 "uname -a" should do.
5431 * The name, platform, and version of the browser you were using (e.g.
5432 Internet Explorer v5.5 for Mac).
5434 * The URL where the problem occurred, or some way for us to duplicate the
5435 problem (e.g. http://somesite.example.com/?somethingelse=123).
5437 * Whether your version of Privoxy is one supplied by the developers of
5438 Privoxy via SourceForge, or somewhere else.
5440 * Whether you are using Privoxy in tandem with another proxy such as Tor. If
5441 so, please try disabling the other proxy.
5443 * Whether you are using a personal firewall product. If so, does Privoxy work
5446 * Any other pertinent information to help identify the problem such as config
5447 or log file excerpts (yes, you should have log file entries for each action
5450 * Please provide your SF login, or email address, in case we need to contact
5453 The appendix of the Privoxy User Manual also has helpful information on
5454 understanding actions, and action debugging.
5456 -------------------------------------------------------------------------------
5458 11.3. Request New Features
5460 You are welcome to submit ideas on new features or other proposals for
5461 improvement through our feature request tracker at http://sourceforge.net/
5462 tracker/?atid=361118&group_id=11118.
5464 -------------------------------------------------------------------------------
5468 For any other issues, feel free to use the mailing lists. Technically
5469 interested users and people who wish to contribute to the project are also
5470 welcome on the developers list! You can find an overview of all Privoxy-related
5471 mailing lists, including list archives, at: http://sourceforge.net/mail/?
5474 -------------------------------------------------------------------------------
5476 12. Privoxy Copyright, License and History
5478 Copyright © 2001 - 2006 by Privoxy Developers <
5479 ijbswa-developers@lists.sourceforge.net>
5481 Some source code is based on code Copyright © 1997 by Anonymous Coders and
5482 Junkbusters, Inc. and licensed under the GNU General Public License.
5484 -------------------------------------------------------------------------------
5488 Privoxy is free software; you can redistribute it and/or modify it under the
5489 terms of the GNU General Public License, version 2, as published by the Free
5490 Software Foundation.
5492 This program is distributed in the hope that it will be useful, but WITHOUT ANY
5493 WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
5494 PARTICULAR PURPOSE. See the GNU General Public License for more details, which
5495 is available from the Free Software Foundation, Inc, 51 Franklin Street, Fifth
5496 Floor, Boston, MA 02110-1301, USA
5498 You should have received a copy of the GNU General Public License along with
5499 this program; if not, write to the
5502 Foundation, Inc. 51 Franklin Street, Fifth Floor
5503 Boston, MA 02110-1301
5506 -------------------------------------------------------------------------------
5510 Along time ago, there was the Internet Junkbuster, by Anonymous Coders and
5511 Junkbusters Corporation. This saved many users a lot of pain in the early days
5512 of web advertising and user tracking.
5514 But the web, its protocols and standards, and with it, the techniques for
5515 forcing ads on users, give up autonomy over their browsing, and for tracking
5516 them, keeps evolving. Unfortunately, the Internet Junkbuster did not. Version
5517 2.0.2, published in 1998, was (and is) the last official release available from
5518 Junkbusters Corporation. Fortunately, it had been released under the GNU GPL,
5519 which allowed further development by others.
5521 So Stefan Waldherr started maintaining an improved version of the software, to
5522 which eventually a number of people contributed patches. It could already
5523 replace banners with a transparent image, and had a first version of pop-up
5524 killing, but it was still very closely based on the original, with all its
5525 limitations, such as the lack of HTTP/1.1 support, flexible per-site
5526 configuration, or content modification. The last release from this effort was
5527 version 2.0.2-10, published in 2000.
5529 Then, some developers picked up the thread, and started turning the software
5530 inside out, upside down, and then reassembled it, adding many new features
5533 The result of this is Privoxy, whose first stable version, 3.0, was released
5536 -------------------------------------------------------------------------------
5540 Current Privoxy Team:
5542 Fabian Keil, developer
5543 David Schmidt, developer
5550 Former Privoxy Team Members:
5574 Thanks to the many people who have tested Privoxy, reported bugs, made
5575 suggestions or contributed in some way. These include (in alphabetical order):
5602 Privoxy is based in part on code originally developed by:
5607 -------------------------------------------------------------------------------
5611 Other references and sites of interest to Privoxy users:
5613 http://www.privoxy.org/, the Privoxy Home page.
5615 http://www.privoxy.org/faq/, the Privoxy FAQ.
5617 http://sourceforge.net/projects/ijbswa/, the Project Page for Privoxy on
5620 http://config.privoxy.org/, the web-based user interface. Privoxy must be
5621 running for this to work. Shortcut: http://p.p/
5623 http://sourceforge.net/tracker/?group_id=11118&atid=460288, to submit "misses"
5624 and other configuration related suggestions to the developers.
5626 http://www.junkbusters.com/ht/en/cookies.html, an explanation how cookies are
5627 used to track web users.
5629 http://www.junkbusters.com/ijb.html, the original Internet Junkbuster.
5631 http://privacy.net/, a useful site to check what information about you is
5632 leaked while you browse the web.
5634 http://www.squid-cache.org/, a very popular caching proxy, which is often used
5635 together with Privoxy.
5637 http://tor.eff.org/, Tor can help anonymize web browsing, web publishing,
5638 instant messaging, IRC, SSH, and other applications.
5640 http://www.privoxy.org/developer-manual/, the Privoxy developer manual.
5642 -------------------------------------------------------------------------------
5646 14.1. Regular Expressions
5648 Privoxy uses Perl-style "regular expressions" in its actions files and filter
5649 file, through the PCRE and PCRS libraries.
5651 If you are reading this, you probably don't understand what "regular
5652 expressions" are, or what they can do. So this will be a very brief
5653 introduction only. A full explanation would require a book ;-)
5655 Regular expressions provide a language to describe patterns that can be run
5656 against strings of characters (letter, numbers, etc), to see if they match the
5657 string or not. The patterns are themselves (sometimes complex) strings of
5658 literal characters, combined with wild-cards, and other special characters,
5659 called meta-characters. The "meta-characters" have special meanings and are
5660 used to build complex patterns to be matched against. Perl Compatible Regular
5661 Expressions are an especially convenient "dialect" of the regular expression
5664 To make a simple analogy, we do something similar when we use wild-card
5665 characters when listing files with the dir command in DOS. *.* matches all
5666 filenames. The "special" character here is the asterisk which matches any and
5667 all characters. We can be more specific and use ? to match just individual
5668 characters. So "dir file?.text" would match "file1.txt", "file2.txt", etc. We
5669 are pattern matching, using a similar technique to "regular expressions"!
5671 Regular expressions do essentially the same thing, but are much, much more
5672 powerful. There are many more "special characters" and ways of building complex
5673 patterns however. Let's look at a few of the common ones, and then some
5676 . - Matches any single character, e.g. "a", "A", "4", ":", or "@".
5678 ? - The preceding character or expression is matched ZERO or ONE times. Either/
5681 + - The preceding character or expression is matched ONE or MORE times.
5683 * - The preceding character or expression is matched ZERO or MORE times.
5685 \ - The "escape" character denotes that the following character should be taken
5686 literally. This is used where one of the special characters (e.g. ".") needs to
5687 be taken literally and not as a special meta-character. Example: "example
5688 \.com", makes sure the period is recognized only as a period (and not expanded
5689 to its meta-character meaning of any single character).
5691 [ ] - Characters enclosed in brackets will be matched if any of the enclosed
5692 characters are encountered. For instance, "[0-9]" matches any numeric digit
5693 (zero through nine). As an example, we can combine this with "+" to match any
5694 digit one of more times: "[0-9]+".
5696 ( ) - parentheses are used to group a sub-expression, or multiple
5699 | - The "bar" character works like an "or" conditional statement. A match is
5700 successful if the sub-expression on either side of "|" matches. As an example:
5701 "/(this|that) example/" uses grouping and the bar character and would match
5702 either "this example" or "that example", and nothing else.
5704 These are just some of the ones you are likely to use when matching URLs with
5705 Privoxy, and is a long way from a definitive list. This is enough to get us
5706 started with a few simple examples which may be more illuminating:
5708 /.*/banners/.* - A simple example that uses the common combination of "." and "
5709 *" to denote any character, zero or more times. In other words, any string at
5710 all. So we start with a literal forward slash, then our regular expression
5711 pattern (".*") another literal forward slash, the string "banners", another
5712 forward slash, and lastly another ".*". We are building a directory path here.
5713 This will match any file with the path that has a directory named "banners" in
5714 it. The ".*" matches any characters, and this could conceivably be more forward
5715 slashes, so it might expand into a much longer looking path. For example, this
5716 could match: "/eye/hate/spammers/banners/annoy_me_please.gif", or just "/
5717 banners/annoying.html", or almost an infinite number of other possible
5718 combinations, just so it has "banners" in the path somewhere.
5720 And now something a little more complex:
5722 /.*/adv((er)?ts?|ertis(ing|ements?))?/ - We have several literal forward
5723 slashes again ("/"), so we are building another expression that is a file path
5724 statement. We have another ".*", so we are matching against any conceivable
5725 sub-path, just so it matches our expression. The only true literal that must
5726 match our pattern is adv, together with the forward slashes. What comes after
5727 the "adv" string is the interesting part.
5729 Remember the "?" means the preceding expression (either a literal character or
5730 anything grouped with "(...)" in this case) can exist or not, since this means
5731 either zero or one match. So "((er)?ts?|ertis(ing|ements?))" is optional, as
5732 are the individual sub-expressions: "(er)", "(ing|ements?)", and the "s". The "
5733 |" means "or". We have two of those. For instance, "(ing|ements?)", can expand
5734 to match either "ing" OR "ements?". What is being done here, is an attempt at
5735 matching as many variations of "advertisement", and similar, as possible. So
5736 this would expand to match just "adv", or "advert", or "adverts", or
5737 "advertising", or "advertisement", or "advertisements". You get the idea. But
5738 it would not match "advertizements" (with a "z"). We could fix that by changing
5739 our regular expression to: "/.*/adv((er)?ts?|erti(s|z)(ing|ements?))?/", which
5740 would then match either spelling.
5742 /.*/advert[0-9]+\.(gif|jpe?g) - Again another path statement with forward
5743 slashes. Anything in the square brackets "[ ]" can be matched. This is using
5744 "0-9" as a shorthand expression to mean any digit one through nine. It is the
5745 same as saying "0123456789". So any digit matches. The "+" means one or more of
5746 the preceding expression must be included. The preceding expression here is
5747 what is in the square brackets -- in this case, any digit one through nine.
5748 Then, at the end, we have a grouping: "(gif|jpe?g)". This includes a "|", so
5749 this needs to match the expression on either side of that bar character also. A
5750 simple "gif" on one side, and the other side will in turn match either "jpeg"
5751 or "jpg", since the "?" means the letter "e" is optional and can be matched
5752 once or not at all. So we are building an expression here to match image GIF or
5753 JPEG type image file. It must include the literal string "advert", then one or
5754 more digits, and a "." (which is now a literal, and not a special character,
5755 since it is escaped with "\"), and lastly either "gif", or "jpeg", or "jpg".
5756 Some possible matches would include: "//advert1.jpg", "/nasty/ads/
5757 advert1234.gif", "/banners/from/hell/advert99.jpg". It would not match
5758 "advert1.gif" (no leading slash), or "/adverts232.jpg" (the expression does not
5759 include an "s"), or "/advert1.jsp" ("jsp" is not in the expression anywhere).
5761 We are barely scratching the surface of regular expressions here so that you
5762 can understand the default Privoxy configuration files, and maybe use this
5763 knowledge to customize your own installation. There is much, much more that can
5764 be done with regular expressions. Now that you know enough to get started, you
5765 can learn more on your own :/
5767 More reading on Perl Compatible Regular expressions: http://perldoc.perl.org/
5770 For information on regular expression based substitutions and their
5771 applications in filters, please see the filter file tutorial in this manual.
5773 -------------------------------------------------------------------------------
5775 14.2. Privoxy's Internal Pages
5777 Since Privoxy proxies each requested web page, it is easy for Privoxy to trap
5778 certain special URLs. In this way, we can talk directly to Privoxy, and see how
5779 it is configured, see how our rules are being applied, change these rules and
5780 other configuration options, and even turn Privoxy's filtering off, all with a
5783 The URLs listed below are the special ones that allow direct access to Privoxy.
5784 Of course, Privoxy must be running to access these. If not, you will get a
5785 friendly error message. Internet access is not necessary either.
5787 * Privoxy main page:
5789 http://config.privoxy.org/
5791 There is a shortcut: http://p.p/ (But it doesn't provide a fall-back to a
5792 real page, in case the request is not sent through Privoxy)
5794 * Show information about the current configuration, including viewing and
5795 editing of actions files:
5797 http://config.privoxy.org/show-status
5799 * Show the source code version numbers:
5801 http://config.privoxy.org/show-version
5803 * Show the browser's request headers:
5805 http://config.privoxy.org/show-request
5807 * Show which actions apply to a URL and why:
5809 http://config.privoxy.org/show-url-info
5811 * Toggle Privoxy on or off. In this case, "Privoxy" continues to run, but
5812 only as a pass-through proxy, with no actions taking place:
5814 http://config.privoxy.org/toggle
5816 Short cuts. Turn off, then on:
5818 http://config.privoxy.org/toggle?set=disable
5820 http://config.privoxy.org/toggle?set=enable
5822 These may be bookmarked for quick reference. See next.
5824 -------------------------------------------------------------------------------
5826 14.2.1. Bookmarklets
5828 Below are some "bookmarklets" to allow you to easily access a "mini" version of
5829 some of Privoxy's special pages. They are designed for MS Internet Explorer,
5830 but should work equally well in Netscape, Mozilla, and other browsers which
5831 support JavaScript. They are designed to run directly from your bookmarks - not
5832 by clicking the links below (although that should work for testing).
5834 To save them, right-click the link and choose "Add to Favorites" (IE) or "Add
5835 Bookmark" (Netscape). You will get a warning that the bookmark "may not be
5836 safe" - just click OK. Then you can run the Bookmarklet directly from your
5837 favorites/bookmarks. For even faster access, you can put them on the "Links"
5838 bar (IE) or the "Personal Toolbar" (Netscape), and run them with a single
5845 * Privoxy - Toggle Privoxy (Toggles between enabled and disabled)
5847 * Privoxy- View Status
5851 Credit: The site which gave us the general idea for these bookmarklets is
5852 www.bookmarklets.com. They have more information about bookmarklets.
5854 -------------------------------------------------------------------------------
5856 14.3. Chain of Events
5858 Let's take a quick look at the basic sequence of events when a web page is
5859 requested by your browser and Privoxy is on duty:
5861 * First, your web browser requests a web page. The browser knows to send the
5862 request to Privoxy, which will in turn, relay the request to the remote web
5863 server after passing the following tests:
5865 * Privoxy traps any request for its own internal CGI pages (e.g http://p.p/)
5866 and sends the CGI page back to the browser.
5868 * Next, Privoxy checks to see if the URL matches any "+block" patterns. If
5869 so, the URL is then blocked, and the remote web server will not be
5870 contacted. "+handle-as-image" is then checked and if it does not match, an
5871 HTML "BLOCKED" page is sent back. Otherwise, if it does match, an image is
5872 returned. The type of image depends on the setting of "+set-image-blocker"
5873 (blank, checkerboard pattern, or an HTTP redirect to an image elsewhere).
5875 * Untrusted URLs are blocked. If URLs are being added to the trust file, then
5878 * If the URL pattern matches the "+fast-redirects" action, it is then
5879 processed. Unwanted parts of the requested URL are stripped.
5881 * Now the rest of the client browser's request headers are processed. If any
5882 of these match any of the relevant actions (e.g. "+hide-user-agent", etc.),
5883 headers are suppressed or forged as determined by these actions and their
5886 * Now the web server starts sending its response back (i.e. typically a web
5887 page and related data).
5889 * First, the server headers are read and processed to determine, among other
5890 things, the MIME type (document type) and encoding. The headers are then
5891 filtered as determined by the "+crunch-incoming-cookies",
5892 "+session-cookies-only", and "+downgrade-http-version" actions.
5894 * If the "+kill-popups" action applies, and it is an HTML or JavaScript
5895 document, the popup-code in the response is filtered on-the-fly as it is
5898 * If a "+filter" or "+deanimate-gifs" action applies (and the document type
5899 fits the action), the rest of the page is read into memory (up to a
5900 configurable limit). Then the filter rules (from default.filter and any
5901 other filter files) are processed against the buffered content. Filters are
5902 applied in the order they are specified in one of the filter files.
5903 Animated GIFs, if present, are reduced to either the first or last frame,
5904 depending on the action setting.The entire page, which is now filtered, is
5905 then sent by Privoxy back to your browser.
5907 If neither "+filter" or "+deanimate-gifs" matches, then Privoxy passes the
5908 raw data through to the client browser as it becomes available.
5910 * As the browser receives the now (possibly filtered) page content, it reads
5911 and then requests any URLs that may be embedded within the page source,
5912 e.g. ad images, stylesheets, JavaScript, other HTML documents (e.g.
5913 frames), sounds, etc. For each of these objects, the browser issues a new
5914 request. And each such request is in turn processed as above. Note that a
5915 complex web page may have many such embedded URLs.
5917 -------------------------------------------------------------------------------
5919 14.4. Troubleshooting: Anatomy of an Action
5921 The way Privoxy applies actions and filters to any given URL can be complex,
5922 and not always so easy to understand what is happening. And sometimes we need
5923 to be able to see just what Privoxy is doing. Especially, if something Privoxy
5924 is doing is causing us a problem inadvertently. It can be a little daunting to
5925 look at the actions and filters files themselves, since they tend to be filled
5926 with regular expressions whose consequences are not always so obvious.
5928 One quick test to see if Privoxy is causing a problem or not, is to disable it
5929 temporarily. This should be the first troubleshooting step. See the
5930 Bookmarklets section on a quick and easy way to do this (be sure to flush
5931 caches afterward!). Looking at the logs is a good idea too.
5933 Another easy troubleshooting step to try is if you have done any customization
5934 of your installation, revert back to the installed defaults and see if that
5935 helps. There are times the developers get complaints about one thing or
5936 another, and the problem is more related to a customized configuration issue.
5938 Privoxy also provides the http://config.privoxy.org/show-url-info page that can
5939 show us very specifically how actions are being applied to any given URL. This
5940 is a big help for troubleshooting.
5942 First, enter one URL (or partial URL) at the prompt, and then Privoxy will tell
5943 us how the current configuration will handle it. This will not help with
5944 filtering effects (i.e. the "+filter" action) from one of the filter files
5945 since this is handled very differently and not so easy to trap! It also will
5946 not tell you about any other URLs that may be embedded within the URL you are
5947 testing. For instance, images such as ads are expressed as URLs within the raw
5948 page source of HTML pages. So you will only get info for the actual URL that is
5949 pasted into the prompt area -- not any sub-URLs. If you want to know about
5950 embedded URLs like ads, you will have to dig those out of the HTML source. Use
5951 your browser's "View Page Source" option for this. Or right click on the ad,
5954 Let's try an example, google.com, and look at it one section at a time in a
5955 sample configuration (your real configuration may vary):
5957 Matches for http://google.com:
5959 In file: default.action [ View ] [ Edit ]
5963 -content-type-overwrite
5964 -crunch-client-header
5965 -crunch-if-none-match
5966 -crunch-incoming-cookies
5967 -crunch-outgoing-cookies
5968 -crunch-server-header
5969 +deanimate-gifs {last}
5970 -downgrade-http-version
5971 +fast-redirects {check-decoded-url}
5973 -filter {content-cookies}
5974 -filter {all-popups}
5975 -filter {banners-by-link}
5976 -filter {tiny-textforms}
5977 -filter {frameset-borders}
5978 -filter {demoronizer}
5979 -filter {shockwave-flash}
5980 -filter {quicktime-kioskmode}
5982 -filter {crude-parental}
5983 -filter {site-specifics}
5984 +filter {js-annoyances}
5985 +filter {html-annoyances}
5986 +filter {refresh-tags}
5987 +filter {unsolicited-popups}
5988 +filter {img-reorder}
5989 +filter {banners-by-size}
5991 +filter {jumping-windows}
5992 +filter {ie-exploits}
5993 -filter-client-headers
5994 -filter-server-headers
5996 -handle-as-empty-document
5998 -hide-accept-language
5999 -hide-content-disposition
6000 +hide-forwarded-for-headers
6001 +hide-from-header {block}
6002 -hide-if-modified-since
6003 +hide-referrer {forge}
6008 -overwrite-last-modified
6009 +prevent-compression
6013 +session-cookies-only
6014 +set-image-blocker {pattern}
6015 -treat-forbidden-connects-like-blocks }
6018 { -session-cookies-only }
6024 In file: user.action [ View ] [ Edit ]
6025 (no matches in this file)
6027 This is telling us how we have defined our "actions", and which ones match for
6028 our test case, "google.com". Displayed is all the actions that are available to
6029 us. Remember, the + sign denotes "on". - denotes "off". So some are "on" here,
6030 but many are "off". Each example we try may provide a slightly different end
6031 result, depending on our configuration directives.
6033 The first listing is for our default.action file. The large, multi-line
6034 listing, is how the actions are set to match for all URLs, i.e. our default
6035 settings. If you look at your "actions" file, this would be the section just
6036 below the "aliases" section near the top. This will apply to all URLs as
6037 signified by the single forward slash at the end of the listing -- " / ".
6039 But we have defined additional actions that would be exceptions to these
6040 general rules, and then we list specific URLs (or patterns) that these
6041 exceptions would apply to. Last match wins. Just below this then are two
6042 explicit matches for ".google.com". The first is negating our previous cookie
6043 setting, which was for "+session-cookies-only" (i.e. not persistent). So we
6044 will allow persistent cookies for google, at least that is how it is in this
6045 example. The second turns off any "+fast-redirects" action, allowing this to
6046 take place unmolested. Note that there is a leading dot here -- ".google.com".
6047 This will match any hosts and sub-domains, in the google.com domain also, such
6048 as "www.google.com" or "mail.google.com". But it would not match
6049 "www.google.de"! So, apparently, we have these two actions defined as
6050 exceptions to the general rules at the top somewhere in the lower part of our
6051 default.action file, and "google.com" is referenced somewhere in these latter
6054 Then, for our user.action file, we again have no hits. So there is nothing
6055 google-specific that we might have added to our own, local configuration. If
6056 there was, those actions would over-rule any actions from previously processed
6057 files, such as default.action. user.action typically has the last word. This is
6058 the best place to put hard and fast exceptions,
6060 And finally we pull it all together in the bottom section and summarize how
6061 Privoxy is applying all its "actions" to "google.com":
6067 -content-type-overwrite
6068 -crunch-client-header
6069 -crunch-if-none-match
6070 -crunch-incoming-cookies
6071 -crunch-outgoing-cookies
6072 -crunch-server-header
6073 +deanimate-gifs {last}
6074 -downgrade-http-version
6076 +filter {js-annoyances}
6077 +filter {html-annoyances}
6078 +filter {refresh-tags}
6079 +filter {unsolicited-popups}
6080 +filter {img-reorder}
6081 +filter {banners-by-size}
6083 +filter {jumping-windows}
6084 +filter {ie-exploits}
6085 -filter-client-headers
6086 -filter-server-headers
6088 -handle-as-empty-document
6090 -hide-accept-language
6091 -hide-content-disposition
6092 +hide-forwarded-for-headers
6093 +hide-from-header {block}
6094 -hide-if-modified-since
6095 +hide-referrer {forge}
6100 -overwrite-last-modified
6101 +prevent-compression
6105 -session-cookies-only
6106 +set-image-blocker {pattern}
6107 -treat-forbidden-connects-like-blocks
6109 Notice the only difference here to the previous listing, is to "fast-redirects"
6110 and "session-cookies-only", which are activated specifically for this site in
6111 our configuration, and thus show in the "Final Results".
6113 Now another example, "ad.doubleclick.net":
6121 { +block +handle-as-image }
6122 .[a-vx-z]*.doubleclick.net
6124 We'll just show the interesting part here - the explicit matches. It is matched
6125 three different times. Two "+block" sections, and a "+block +handle-as-image",
6126 which is the expanded form of one of our aliases that had been defined as:
6127 "+block-as-image". ("Aliases" are defined in the first section of the actions
6128 file and typically used to combine more than one action.)
6130 Any one of these would have done the trick and blocked this as an unwanted
6131 image. This is unnecessarily redundant since the last case effectively would
6132 also cover the first. No point in taking chances with these guys though ;-)
6133 Note that if you want an ad or obnoxious URL to be invisible, it should be
6134 defined as "ad.doubleclick.net" is done here -- as both a "+block" and an
6135 "+handle-as-image". The custom alias "+block-as-image" just simplifies the
6136 process and make it more readable.
6138 One last example. Let's try "http://www.example.net/adsl/HOWTO/". This one is
6139 giving us problems. We are getting a blank page. Hmmm ...
6141 Matches for http://www.example.net/adsl/HOWTO/:
6143 In file: default.action [ View ] [ Edit ]
6147 -content-type-overwrite
6148 -crunch-client-header
6149 -crunch-if-none-match
6150 -crunch-incoming-cookies
6151 -crunch-outgoing-cookies
6152 -crunch-server-header
6154 -downgrade-http-version
6155 +fast-redirects{check-decoded-url}
6156 +filter{html-annoyances}
6157 +filter{js-annoyances}
6158 +filter{kill-popups}
6161 +filter{banners-by-size}
6164 -filter-client-headers
6165 -filter-server-headers
6167 -handle-as-empty-document
6169 -hide-accept-language
6170 -hide-content-disposition
6171 +hide-forwarded-for-headers
6172 +hide-from-header{block}
6173 +hide-referer{forge}
6177 -overwrite-last-modified
6178 +prevent-compression
6182 +session-cookies-only
6183 +set-image-blocker{blank}
6184 -treat-forbidden-connects-like-blocks }
6187 { +block +handle-as-image }
6190 Ooops, the "/adsl/" is matching "/ads" in our configuration! But we did not
6191 want this at all! Now we see why we get the blank page. It is actually
6192 triggering two different actions here, and the effects are aggregated so that
6193 the URL is blocked, and Privoxy is told to treat the block as if it were an
6194 image. But this is, of course, all wrong. We could now add a new action below
6195 this (or better in our own user.action file) that explicitly un blocks ( "
6196 {-block}") paths with "adsl" in them (remember, last match in the configuration
6197 wins). There are various ways to handle such exceptions. Example:
6202 Now the page displays ;-) Remember to flush your browser's caches when making
6203 these kinds of changes to your configuration to insure that you get a freshly
6204 delivered page! Or, try using Shift+Reload.
6206 But now what about a situation where we get no explicit matches like we did
6209 { +block +handle-as-image }
6212 That actually was very helpful and pointed us quickly to where the problem was.
6213 If you don't get this kind of match, then it means one of the default rules in
6214 the first section of default.action is causing the problem. This would require
6215 some guesswork, and maybe a little trial and error to isolate the offending
6216 rule. One likely cause would be one of the "+filter" actions. These tend to be
6217 harder to troubleshoot. Try adding the URL for the site to one of aliases that
6222 .worldpay.com # for quietpc.com
6227 "{ shop }" is an "alias" that expands to "{ -filter -session-cookies-only }".
6228 Or you could do your own exception to negate filtering:
6231 # Disable ALL filter actions for sites in this section
6236 This would turn off all filtering for these sites. This is best put in
6237 user.action, for local site exceptions. Note that when a simple domain pattern
6238 is used by itself (without the subsequent path portion), all sub-pages within
6239 that domain are included automatcially in the scope of the action.
6241 Images that are inexplicably being blocked, may well be hitting the "+filter
6242 {banners-by-size}" rule, which assumes that images of certain sizes are ad
6243 banners (works well most of the time since these tend to be standardized).
6245 "{ fragile }" is an alias that disables most actions that are the most likely
6246 to cause trouble. This can be used as a last resort for problem sites.
6249 # Handle with care: easy to break
6253 Remember to flush caches! Note that the mail.google reference lacks the TLD
6254 portion (e.g. ".com". This will effectively match any TLD with google in it,
6255 such as mail.google.de, just as an example.
6257 If this still does not work, you will have to go through the remaining actions
6258 one by one to find which one(s) is causing the problem.