-Privoxy User Manual
+Privoxy 3.0.5 User Manual
-By: Privoxy Developers
+Copyright © 2001 - 2006 by Privoxy Developers
-$Id: user-manual.sgml,v 1.102 2002/05/03 17:46:00 oes Exp $
+$Id: user-manual.sgml,v 2.22 2006/09/22 01:27:55 hal9 Exp $
-The user manual gives users information on how to install, configure and use
-Privoxy.
+The Privoxy User Manual gives users information on how to install, configure
+and use Privoxy.
Privoxy is a web proxy with advanced filtering capabilities for protecting
-privacy, filtering web page content, managing cookies, controlling access, and
+privacy, modifying web page data, managing cookies, controlling access, and
removing ads, banners, pop-ups and other obnoxious Internet junk. Privoxy has a
very flexible configuration and can be customized to suit individual needs and
tastes. Privoxy has application for both stand-alone systems and multi-user
Privoxy is based on Internet Junkbuster (tm).
-You can find the latest version of the user manual at http://www.privoxy.org/
-user-manual/. Please see the Contact section on how to contact the developers.
+You can find the latest version of the Privoxy User Manual at http://
+www.privoxy.org/user-manual/. Please see the Contact section on how to contact
+the developers.
-------------------------------------------------------------------------------
2.1. Binary Packages
- 2.1.1. Red Hat and SuSE RPMs
+ 2.1.1. Red Hat, SuSE and Conectiva RPMs
2.1.2. Debian
2.1.3. Windows
2.1.4. Solaris, NetBSD, FreeBSD, HP-UX
2.1.5. OS/2
- 2.1.6. Max OSX
+ 2.1.6. Mac OSX
2.1.7. AmigaOS
+ 2.1.8. Gentoo
2.2. Building from Source
+ 2.3. Keeping your Installation Up-to-Date
+
+3. What's New in this Release
+
+ 3.1. Note to Upgraders
-3. Note to Upgraders
4. Quickstart to Using Privoxy
+
+ 4.1. Quickstart to Ad Blocking
+
5. Starting Privoxy
- 5.1. RedHat and Debian
- 5.2. SuSE
- 5.3. Windows
- 5.4. Solaris, NetBSD, FreeBSD, HP-UX and others
- 5.5. OS/2
- 5.6. MAX OSX
- 5.7. AmigaOS
- 5.8. Command Line Options
+ 5.1. Red Hat, Fedora and Conectiva
+ 5.2. Debian
+ 5.3. SuSE
+ 5.4. Windows
+ 5.5. Solaris, NetBSD, FreeBSD, HP-UX and others
+ 5.6. OS/2
+ 5.7. Mac OSX
+ 5.8. AmigaOS
+ 5.9. Gentoo
+ 5.10. Command Line Options
6. Privoxy Configuration
7. The Main Configuration File
- 7.1. Configuration and Log File Locations
+ 7.1. Local Set-up Documentation
- 7.1.1. confdir
- 7.1.2. logdir
- 7.1.3. actionsfile
- 7.1.4. filterfile
- 7.1.5. logfile
- 7.1.6. jarfile
- 7.1.7. trustfile
+ 7.1.1. user-manual
+ 7.1.2. trust-info-url
+ 7.1.3. admin-address
+ 7.1.4. proxy-info-url
- 7.2. Local Set-up Documentation
+ 7.2. Configuration and Log File Locations
- 7.2.1. user-manual
- 7.2.2. trust-info-url
- 7.2.3. admin-address
- 7.2.4. proxy-info-url
+ 7.2.1. confdir
+ 7.2.2. logdir
+ 7.2.3. actionsfile
+ 7.2.4. filterfile
+ 7.2.5. logfile
+ 7.2.6. jarfile
+ 7.2.7. trustfile
7.3. Debugging
7.4.1. listen-address
7.4.2. toggle
7.4.3. enable-remote-toggle
- 7.4.4. enable-edit-actions
- 7.4.5. ACLs: permit-access and deny-access
- 7.4.6. buffer-limit
+ 7.4.4. enable-remote-http-toggle
+ 7.4.5. enable-edit-actions
+ 7.4.6. ACLs: permit-access and deny-access
+ 7.4.7. buffer-limit
7.5. Forwarding
7.5.1. forward
7.5.2. forward-socks4 and forward-socks4a
7.5.3. Advanced Forwarding Examples
+ 7.5.4. forwarded-connect-retries
7.6. Windows GUI Options
8.5. Actions
- 8.5.1. +add-header
- 8.5.2. +block
- 8.5.3. +deanimate-gifs
- 8.5.4. +downgrade-http-version
- 8.5.5. +fast-redirects
- 8.5.6. +filter
- 8.5.7. +hide-forwarded-for-headers
- 8.5.8. +hide-from-header
- 8.5.9. +hide-referer
- 8.5.10. +hide-user-agent
- 8.5.11. +handle-as-image
- 8.5.12. +set-image-blocker
- 8.5.13. +limit-connect
- 8.5.14. +prevent-compression
- 8.5.15. +session-cookies-only
- 8.5.16. +prevent-reading-cookies
- 8.5.17. +prevent-setting-cookies
- 8.5.18. +kill-popups
- 8.5.19. +send-vanilla-wafer
- 8.5.20. +send-wafer
- 8.5.21. Summary
- 8.5.22. Sample Actions Files
+ 8.5.1. add-header
+ 8.5.2. block
+ 8.5.3. content-type-overwrite
+ 8.5.4. crunch-client-header
+ 8.5.5. crunch-if-none-match
+ 8.5.6. crunch-incoming-cookies
+ 8.5.7. crunch-server-header
+ 8.5.8. crunch-outgoing-cookies
+ 8.5.9. deanimate-gifs
+ 8.5.10. downgrade-http-version
+ 8.5.11. fast-redirects
+ 8.5.12. filter
+ 8.5.13. filter-client-headers
+ 8.5.14. filter-server-headers
+ 8.5.15. force-text-mode
+ 8.5.16. handle-as-empty-document
+ 8.5.17. handle-as-image
+ 8.5.18. hide-accept-language
+ 8.5.19. hide-content-disposition
+ 8.5.20. hide-if-modified-since
+ 8.5.21. hide-forwarded-for-headers
+ 8.5.22. hide-from-header
+ 8.5.23. hide-referrer
+ 8.5.24. hide-user-agent
+ 8.5.25. inspect-jpegs
+ 8.5.26. kill-popups
+ 8.5.27. limit-connect
+ 8.5.28. prevent-compression
+ 8.5.29. overwrite-last-modified
+ 8.5.30. redirect
+ 8.5.31. send-vanilla-wafer
+ 8.5.32. send-wafer
+ 8.5.33. session-cookies-only
+ 8.5.34. set-image-blocker
+ 8.5.35. treat-forbidden-connects-like-blocks
+ 8.5.36. Summary
8.6. Aliases
+ 8.7. Actions Files Tutorial
+
+ 8.7.1. default.action
+ 8.7.2. user.action
+
+9. Filter Files
-9. The Filter File
-
- 9.1. The +filter Action
+ 9.1. Filter File Tutorial
+ 9.2. The Pre-defined Filters
-10. Templates
+10. Privoxy's Template Files
11. Contacting the Developers, Bug Reporting and Feature Requests
11.1. Get Support
- 11.2. Report bugs
- 11.3. Request new features
- 11.4. Report ads or other filter problems
- 11.5. Other
+ 11.2. Reporting Problems
+
+ 11.2.1. Reporting Ads or Other Configuration Problems
+ 11.2.2. Reporting Bugs
+
+ 11.3. Request New Features
+ 11.4. Other
-12. Copyright and History
+12. Privoxy Copyright, License and History
- 12.1. Copyright
+ 12.1. License
12.2. History
+ 12.3. Authors
13. See Also
14. Appendix
14.2.1. Bookmarklets
14.3. Chain of Events
- 14.4. Anatomy of an Action
+ 14.4. Troubleshooting: Anatomy of an Action
1. Introduction
-This documentation is included with the current beta version of Privoxy,
-v.2.9.14, and is mostly complete at this point. The most up to date reference
+This documentation is included with the current BETA version of Privoxy,
+v.3.0.5, and is mostly complete at this point. The most up to date reference
for the time being is still the comments in the source files and in the
-individual configuration files. Development of version 3.0 is currently nearing
-completion, and includes many significant changes and enhancements over earlier
-versions. The target release date for stable v3.0 is "soon" ;-).
+individual configuration files. Development of a new version is currently
+nearing completion, and includes significant changes and enhancements over
+earlier versions. .
-Since this is a beta version, not all new features are well tested. This
+Since this is a BETA version, not all new features are well tested. This
documentation may be slightly out of sync as a result (especially with CVS
sources). And there may be bugs, though hopefully not many!
1.1. Features
-In addition to Internet Junkbuster's traditional features of ad and banner
-blocking and cookie management, Privoxy provides new features, some of them
-currently under development:
+In addition to the core features of ad blocking and cookie management, Privoxy
+provides many supplemental features, some of them currently under development,
+that give the end-user more control, more privacy and more freedom:
* Integrated browser based configuration and control utility at http://
config.privoxy.org/ (shortcut: http://p.p/). Browser-based tracing of rule
* Modularized configuration that allows for standard settings and user
settings to reside in separate files, so that installing updated actions
- files won't overwrite idividual user settings.
+ files won't overwrite individual user settings.
* HTTP/1.1 compliant (but not all optional 1.1 features are supported).
of operating systems, and as raw source code. For most users, we recommend
using the packages, which can be downloaded from our Privoxy Project Page.
-Note: If you have a previous Junkbuster or Privoxy installation on your system,
-you will need to remove it. Some platforms do this for you as part of their
-installation procedure. (See below for your platform). In any case be sure to
+Note: On some platforms, the installer may remove previously installed
+versions, if found. (See below for your platform). In any case be sure to
backup your old configuration if it is valuable to you. See the note to
upgraders section below.
-------------------------------------------------------------------------------
-2.1.1. Red Hat and SuSE RPMs
+2.1.1. Red Hat, SuSE and Conectiva RPMs
-RPMs can be installed with rpm -Uvh privoxy-2.9.14-1.rpm, and will use /etc/
+RPMs can be installed with rpm -Uvh privoxy-3.0.5-1.rpm, and will use /etc/
privoxy for the location of configuration files.
Note that on Red Hat, Privoxy will not be automatically started on system boot.
-You will need to enable that using chkconfig, ntsysv, or similar methods. Note
-that SuSE will automatically start Privoxy in the boot process.
+You will need to enable that using chkconfig, ntsysv, or similar methods.
If you have problems with failed dependencies, try rebuilding the SRC RPM: rpm
---rebuild privoxy-2.9.14-1.src.rpm;. This will use your locally installed
+--rebuild privoxy-3.0.5-1.src.rpm. This will use your locally installed
libraries and RPM version.
Also note that if you have a Junkbuster RPM installed on your system, you need
to remove it first, because the packages conflict. Otherwise, RPM will try to
-remove Junkbuster automatically, before installing Privoxy.
+remove Junkbuster automatically if found, before installing Privoxy.
-------------------------------------------------------------------------------
2.1.2. Debian
-FIXME.
+DEBs can be installed with apt-get install privoxy, and will use /etc/privoxy
+for the location of configuration files.
-------------------------------------------------------------------------------
Just double-click the installer, which will guide you through the installation
process. You will find the configuration files in the same directory as you
-installed Privoxy in. We do not use the registry of Windows.
+installed Privoxy in.
+
+Version 3.0.4 introduced full Windows service functionality. On Windows only,
+the Privoxy program has two new command line arguments to install and uninstall
+Privoxy as a service.
+
+Arguments:
+
+ --install[:service_name]
+
+ --uninstall[:service_name]
+
+After invoking Privoxy with --install, you will need to bring up the Windows
+service console to assign the user you want Privoxy to run under, and whether
+or not you want it to run whenever the system starts. You can start the Windows
+services console with the following command: services.msc. If you do not take
+the manual step of modifying Privoxy's service settings, it will not start.
+Note too that you will need to give Privoxy a user account that actually
+exists, or it will not be permitted to write to its log and configuration
+files.
-------------------------------------------------------------------------------
2.1.4. Solaris, NetBSD, FreeBSD, HP-UX
Create a new directory, cd to it, then unzip and untar the archive. For the
-most part, you'll have to figure out where things go. FIXME.
+most part, you'll have to figure out where things go.
-------------------------------------------------------------------------------
2.1.5. OS/2
First, make sure that no previous installations of Junkbuster and / or Privoxy
-are left on your system. You can do this by
+are left on your system. Check that no Junkbuster or Privoxy objects are in
+your startup folder.
Then, just double-click the WarpIN self-installing archive, which will guide
you through the installation process. A shadow of the Privoxy executable will
-------------------------------------------------------------------------------
-2.1.6. Max OSX
+2.1.6. Mac OSX
-Unzip the downloaded package (you can either double-click on the file in the
-finder, or on the desktop if you downloaded it there). Then, double-click on
-the package installer icon and follow the installation process. Privoxy will be
-installed in the subdirectory /Applications/Privoxy.app. Privoxy will set
-itself up to start automatically on system bring-up via /System/Library/
-StartupItems/Privoxy.
+Unzip the downloaded file (you can either double-click on the file from the
+finder, or from the desktop if you downloaded it there). Then, double-click on
+the package installer icon named Privoxy.pkg and follow the installation
+process. Privoxy will be installed in the folder /Library/Privoxy. It will
+start automatically whenever you start up. To prevent it from starting
+automatically, remove or rename the folder /Library/StartupItems/Privoxy.
+
+To start Privoxy by hand, double-click on StartPrivoxy.command in the /Library/
+Privoxy folder. Or, type this command in the Terminal:
+
+ /Library/Privoxy/StartPrivoxy.command
+
+
+You will be prompted for the administrator password.
-------------------------------------------------------------------------------
files will be installed into Privoxy directory, including all configuration and
log files. To uninstall, just remove this directory.
-Start Privoxy (with RUN <>NIL:) in your startnet script (AmiTCP), in s:
-user-startup (RoadShow), as startup program in your startup script (Genesis),
-or as startup action (Miami and MiamiDx). Privoxy will automatically quit when
-you quit your TCP/IP stack (just ignore the harmless warning your TCP/IP stack
-may display that Privoxy is still running).
+-------------------------------------------------------------------------------
+
+2.1.8. Gentoo
+
+Gentoo source packages (Ebuilds) for Privoxy are contained in the Gentoo
+Portage Tree (they are not on the download page, but there is a Gentoo section,
+where you can see when a new Privoxy Version is added to the Portage Tree).
+
+Before installing Privoxy under Gentoo just do first emerge rsync to get the
+latest changes from the Portage tree. With emerge privoxy you install the
+latest version.
+
+Configuration files are in /etc/privoxy, the documentation is in /usr/share/doc
+/privoxy-3.0.5 and the Log directory is in /var/log/privoxy.
-------------------------------------------------------------------------------
If you like to live on the bleeding edge and are not afraid of using possibly
unstable development versions, you can check out the up-to-the-minute version
-directly from the CVS repository or simply download the nightly CVS tarball.
+directly from the CVS repository.
To build Privoxy from source, autoconf, GNU make (gmake), and, of course, a C
compiler like gcc are required.
-When building from a source tarball (either release version or nightly CVS
-tarball), first unpack the source:
+When building from a source tarball, first unpack the source:
- tar xzvf privoxy-2.9.14-beta-src* [.tgz or .tar.gz]
- cd privoxy-2.9.14-beta
+ tar xzvf privoxy-3.0.5-beta-src* [.tgz or .tar.gz]
+ cd privoxy-3.0.5-beta
-For retrieving the current CVS sources, you'll need CVS installed. Note that
-sources from CVS are development quality, and may not be stable, or well
-tested. To download CVS source:
+For retrieving the current CVS sources, you'll need a CVS client installed.
+Note that sources from CVS are typicially development quality, and may not be
+stable, or well tested. To download CVS source, check the Sourceforge
+documentation, which might give commands like:
- cvs -d:pserver:anonymous@cvs.ijbswa.sourceforge.net:/cvsroot/ijbswa login
- cvs -z3 -d:pserver:anonymous@cvs.ijbswa.sourceforge.net:/cvsroot/ijbswa co current
+ cvs -d:pserver:anonymous@ijbswa.cvs.sourceforge.net:/cvsroot/ijbswa login
+ cvs -z3 -d:pserver:anonymous@ijbswa.cvs.sourceforge.net:/cvsroot/ijbswa co current
cd current
This will create a directory named current/, which will contain the source
tree.
-Then, in either case, to build from unpacked tarball or CVS source:
+You can also check out any Privoxy "branch", just exchange the current name
+with the wanted branch name (Example: v_3_0_branch for the 3.0 cvs tree).
+
+It is also strongly recommended to not run Privoxy as root, and instead it is
+suggested to create a "privoxy" user and group for this purpose. See your local
+documentation for the correct command line to do this.
+
+/etc/passwd might then look like:
+
+ privoxy:*:7777:7777:privoxy proxy:/no/home:/no/shell
+
+And then /etc/group, like:
+
+ privoxy:*:7777:
+
+Some binary packages may do this for you.
+
+Then, to build from either unpacked tarball or CVS source:
autoheader
autoconf
./configure # (--help to see options)
- make # (the make from gnu, gmake for *BSD)
+ make # (the make from GNU, sometimes called gmake)
su
make -n install # (to see where all the files will go)
- make install # (to really install)
+ make -s install # (to really install, -s to silence output)
-If you have gnu make, you can have the first four steps automatically done for
+If you have GNU make, you can have the first four steps automatically done for
you by just typing:
make
in the freshly downloaded or unpacked source directory.
-For more detailed instructions on how to build Redhat and SuSE RPMs, Windows
+WARNING: If installing as root, the install will fail unless a non-root user or
+group is specified, or a privoxy user and group already exist on the system. If
+a non-root user is specified, and no group, then the installation will try to
+also use a group of the same name as "user". If a group is specified (and no
+user), then the support files will be installed as writable by that group, and
+owned by the user running the installation.
+
+configure accepts --with-user and --with-group options for setting user and
+group ownership of the configuration files (which need to be writable by the
+daemon). The specified user must already exist. When starting Privoxy, it
+should be run as this same user to insure write access to configuration and log
+files.
+
+Alternately, you can specify user and group on the make command line, but be
+sure both already exist:
+
+ make -s install USER=privoxy GROUP=privoxy
+
+The default installation path for make install is /usr/local. This may of
+course be customized with the various ./configure path options. If you are
+doing a root install to anywhere else besides /usr/local, be sure to set the
+appropriate paths with the correct configure options (./configure --help).
+
+If you do install to /usr/local, the install will use sysconfdir=$prefix/etc/
+privoxy by default. All other destinations, and the direct usage of
+--sysconfdir flag behave like normal, i.e. will not add the extra privoxy
+directory. This is for a safer install, as there may already exist another
+program that uses a file with the "config" name, and thus makes /usr/local/etc
+cleaner.
+
+If installing to /usr/local, the docs will go by default to $prefix/share/doc.
+But if this directory doesn't exist, it will then try $prefix/doc and install
+there before creating a new $prefix/share/doc just for Privoxy.
+
+Again, if the installs goes to /usr/local, the localstatedir (ie: var/) will
+default to /var instead of $prefix/var so the logs will go to /var/log/privoxy
+/, and the pid file will be created in /var/run/privoxy.pid.
+
+make install will attempt to set the correct values in config (main
+configuration file). You may want to check this to make sure all values are
+correct. If appropriate, an init script will be installed, but it is up to the
+user to determine how and where to start Privoxy. The init script should be
+checked for correct paths and values, if anything other than a default install
+is done.
+
+If install finds previous versions of any local configuration files, these will
+not be overwritten, and the new ones will be installed with a "new" extension.
+default.action, default.filter, and standard.action will be overwritten. You
+will then need to manually update the other installed configuration files as
+needed. All template files will be overwritten. If you have customized, local
+templates, you should save these first. If a previous version of Privoxy is
+already running, you will have to restart it manually.
+
+For more detailed instructions on how to build Redhat RPMs, Windows
self-extracting installers, building on platforms with special requirements
etc, please consult the developer manual.
-------------------------------------------------------------------------------
-3. Note to Upgraders
+2.3. Keeping your Installation Up-to-Date
-There are very significant changes from earlier Junkbuster versions to the
-current Privoxy. The number, names, syntax, and purposes of configuration files
-have substantially changed. Junkbuster 2.0.x configuration files will not
-migrate, Junkbuster 2.9.x and Privoxy configurations will need to be ported.
-The functionalities of the old blockfile, cookiefile and imagelist are now
-combined into the "actions files". default.action, is the main actions file.
-Local exceptions should best be put into user.action.
+As user feedback comes in and development continues, we will make updated
+versions of both the main actions file (as a separate package) and the software
+itself (including the actions file) available for download.
-A "filter file" (typically default.filter) is new as of Privoxy 2.9.x, and
-provides some of the new sophistication (explained below). config is much the
-same as before.
+If you wish to receive an email notification whenever we release updates of
+Privoxy or the actions file, subscribe to our announce mailing list,
+ijbswa-announce@lists.sourceforge.net.
-If upgrading from a 2.0.x version, you will have to use the new config files,
-and possibly adapt any personal rules from your older files. When porting
-personal rules over from the old blockfile to the new actions files, please
-note that even the pattern syntax has changed. If upgrading from 2.9.x
-development versions, it is still recommended to use the new configuration
-files.
+In order not to lose your personal changes and adjustments when updating to the
+latest default.action file we strongly recommend that you use user.action and
+user.filter for your local customizations of Privoxy. See the Chapter on
+actions files for details.
+
+-------------------------------------------------------------------------------
+
+3. What's New in this Release
+
+There are many improvements and new features in Privoxy 3.0.5 :
+
+ * Multiple filter files can now be specified in config. This allows for
+ locally defined filters that can be maintained separately from the filters
+ as supplied by the developers, i.e. default.filter.
+
+ * There are a number of new actions:
+
+ + content-type-overwrite
+
+ + crunch-client-header
+
+ + crunch-if-none-match
+
+ + crunch-server-header
+
+ + filter-client-headers
+
+ + filter-server-headers
+
+ + force-text-mode
+
+ + handle-as-empty-document
+
+ + hide-accept-language
+
+ + hide-content-disposition
+
+ + hide-if-modified-since
+
+ + inspect-jpegs
+
+ + overwrite-last-modified
+
+ + redirect
+
+ + treat-forbidden-connects-like-blocks
+
+ In addition, fast-redirects has been significantly improved with enhanced
+ syntax.
+
+ And hide-referrer has a new option, conditional block.
+
+ * MS-Windows versions can now be installed and started as a Windows service.
+
+ * config has two new options: enable-remote-http-toggle, and
+ forwarded-connect-retries.
+
+ And there is improved handling of the user-manual option, for placing
+ documentation and help files on the local system.
+
+ * Actions files problems and suggestions are now being directed to: http://
+ sourceforge.net/tracker/?group_id=11118&atid=460288. Please use this to
+ report such configuration related problems as missed ads, sites that don't
+ function properly due to one action or another, innocent images being
+ blocked, etc.
+
+ * In addition, there are numerous bug fixes and significant enhancements,
+ including error pages should no longer be cached if the problem is fixed,
+ much better DNS error handling, and various logging improvements.
+
+ * The default actions setting is now Cautious. Previous releases had a
+ default setting of Medium. Experienced users may want to adjust this, as it
+ is fairly conservative by Privoxy standards and past practices. See http://
+ config.privoxy.org/edit-actions-list?f=default. New users should try the
+ default settings for a while before turning up the volume.
+
+-------------------------------------------------------------------------------
+
+3.1. Note to Upgraders
-A quick list of things to be aware of before upgrading:
+A quick list of things to be aware of before upgrading from earlier versions of
+Privoxy:
- * The default listening port is now 8118 due to a conflict with another
- service (NAS).
+ * Some installers may remove earlier versions completely, including
+ configuration files. Save any important configuration files!
- * Some installers may remove earlier versions completely. Save any important
- configuration files!
+ * On the other hand, other installers may not overwrite any existing
+ configuration files, thinking you will want to do that. You may want to
+ manually check your saved files against the newer versions to see if the
+ improvements have merit, or whether there are new options that you may want
+ to consider. There are a number of new features, but most won't be
+ available unless these features are incorporated into your configuration
+ somehow.
- * Privoxy is controllable with a web browser at the special URL: http://
- config.privoxy.org/ (Shortcut: http://p.p/). Many aspects of configuration
- can be done here, including temporarily disabling Privoxy.
+ * See the full documentation on fast-redirects which has changed syntax, and
+ will require adjustments to local configs, such as user.action. You must
+ reference the new syntax:
- * The primary configuration file for cookie management, ad and banner
- blocking, and many other aspects of Privoxy configuration is in the actions
- files. It is strongly recommended to become familiar with the new actions
- concept below, before modifying these files. Locally defined rules should
- go into user.action.
+ { +fast-redirects{check-decoded-url} }
+ .example.com
+ mybank.com
+ .google.
+
+ * The jarfile, cookie logger, is off by default now.
+
+ * What constitutes a "default" configuration has changed, and you may want to
+ review which actions are "on" by default. This is primarily a matter of
+ emphasis, but some features you may have been used to, may now be "off" by
+ default. There are also a number of new actions you may want to consider,
+ most of which are not incorporated into the default settings as yet (see
+ above).
* Some installers may not automatically start Privoxy after installation.
4. Quickstart to Using Privoxy
- * If upgrading, please back up any configuration files. See the Note to
- Upgraders Section.
-
- * Install Privoxy. See the Installation Section for platform specific
+ * Install Privoxy. See the Installation Section below for platform specific
information.
- * Start Privoxy, if the installation program has not done this already. See
- the section Starting Privoxy.
+ * Advanced users and those who want to offer Privoxy service to more than
+ just their local machine should check the main config file, especially the
+ security-relevant options. These are off by default.
+
+ * Start Privoxy, if the installation program has not done this already (may
+ vary according to platform). See the section Starting Privoxy.
- * Set your browser to use Privoxy as HTTP and HTTPS proxy by setting the
- proxy configuration for address of localhost and port 8118. (Junkbuster and
- earlier versions of Privoxy used port 8000.) See the section Starting
- Privoxy.
+ * Set your browser to use Privoxy as HTTP and HTTPS (SSL) proxy by setting
+ the proxy configuration for address of 127.0.0.1 and port 8118. DO NOT
+ activate proxying for FTP or any protocols besides HTTP and HTTPS (SSL)! It
+ won't work!
- * Flush your browser's caches, to remove any cached ad images.
+ * Flush your browser's disk and memory caches, to remove any cached ad
+ images. If using Privoxy to manage cookies, you should remove any currently
+ stored cookies too.
- * Enjoy surfing with enhanced comfort and privacy. You may want to customize
- the user.action file to personalize your new browsing experience. See the
- Configuration section for more configuration options, and how to further
- customize your installation.
+ * A default installation should provide a reasonable starting point for most.
+ There will undoubtedly be occasions where you will want to adjust the
+ configuration, but that can be dealt with as the need arises. Little to no
+ initial configuration is required in most cases.
- * If you experience problems with sites that "misbehave", see the Anatomy of
- an Action section in the Appendix.
+ See the Configuration section for more configuration options, and how to
+ customize your installation. You might also want to look at the next
+ section for a quick introduction to how Privoxy blocks ads and banners.
- * Please see the section Contacting the Developers on how to report bugs or
+ * If you experience ads that slip through, innocent images that are blocked,
+ or otherwise feel the need to fine-tune Privoxy's behavior, take a look at
+ the actions files. As a quick start, you might find the richly commented
+ examples helpful. You can also view and edit the actions files through the
+ web-based user interface. The Appendix "Troubleshooting: Anatomy of an
+ Action" has hints how to understand and debug actions that "misbehave".
+
+ * For easy access to Privoxy's most important controls, drag the provided
+ Bookmarklets into your browser's personal toolbar.
+
+ * Please see the section Contacting the Developers on how to report bugs,
problems with websites or to get help.
+ * Now enjoy surfing with enhanced control, comfort and privacy!
+
+-------------------------------------------------------------------------------
+
+4.1. Quickstart to Ad Blocking
+
+Ad blocking is but one of Privoxy's array of features. Many of these features
+are for the technically minded advanced user. But, ad and banner blocking is
+surely common ground for everybody.
+
+This section will provide a quick summary of ad blocking so you can get up to
+speed quickly without having to read the more extensive information provided
+below, though this is highly recommended.
+
+First a bit of a warning ... blocking ads is much like blocking SPAM: the more
+aggressive you are about it, the more likely you are to block things that were
+not intended. So there is a trade off here. If you want extreme ad free
+browsing, be prepared to deal with more "problem" sites, and to spend more time
+adjusting the configuration to solve these unintended consequences. In short,
+there is not an easy way to eliminate all ads. Either take the easy way and
+settle for most ads blocked with the default configuration, or jump in and
+tweak it for your personal surfing habits and preferences.
+
+Secondly, a brief explanation of Privoxy's "actions". "Actions" in this
+context, are the directives we use to tell Privoxy to perform some task
+relating to HTTP transactions (i.e. web browsing). We tell Privoxy to take some
+"action". Each action has a unique name and function. While there are many
+potential actions in Privoxy's arsenal, only a few are used for ad blocking.
+Actions, and action configuration files, are explained in depth below.
+
+Actions are specified in Privoxy's configuration, followed by one or more URLs
+to which the action should apply. URLs can actually be URL type patterns that
+use wildcards so they can apply potentially to a range of similar URLs. The
+actions, together with the URL patterns are called a section.
+
+When you connect to a website, the full URL will either match one or more of
+the sections as defined in Privoxy's configuration, or not. If so, then Privoxy
+will perform the respective actions. If not, then nothing special happens.
+Furthermore, web pages may contain embedded, secondary URLs that your web
+browser will use to load additional components of the page, as it parses the
+original page's HTML content. An ad image for instance, is just an URL embedded
+in the page somewhere. The image itself may be on the same server, or a server
+somewhere else on the Internet. Complex web pages will have many such embedded
+URLs.
+
+The actions we need to know about for ad blocking are: block, handle-as-image,
+and set-image-blocker:
+
+ * block - this action stops any contact between your browser and any URL
+ patterns that match this action's configuration. It can be used for
+ blocking ads, but also anything that is determined to be unwanted. By
+ itself, it simply stops any communication with the remote server and sends
+ Privoxy's own built-in BLOCKED page instead to let you now what has
+ happened.
+
+ * handle-as-image - tells Privoxy to treat this URL as an image. Privoxy's
+ default configuration already does this for all common image types (e.g.
+ GIF), but there are many situations where this is not so easy to determine.
+ So we'll force it in these cases. This is particularly important for ad
+ blocking, since only if we know that it's an image of some kind, can we
+ replace it with an image of our choosing, instead of the Privoxy BLOCKED
+ page (which would only result in a "broken image" icon). There are some
+ limitations to this though. For instance, you can't just brute-force an
+ image substitution for an entire HTML page in most situations.
+
+ * set-image-blocker - tells Privoxy what to display in place of an ad image
+ that has hit a block rule. For this to come into play, the URL must match a
+ block action somewhere in the configuration, and, it must also match an
+ handle-as-image action.
+
+ The configuration options on what to display instead of the ad are:
+
+ pattern - a checkerboard pattern, so that an ad replacement is obvious.
+ This is the default.
+
+ blank - A very small empty GIF image is displayed. This is the so-called
+ "invisible" configuration option.
+
+ http://<URL> - A redirect to any image anywhere of the user's choosing
+ (advanced usage).
+
+The quickest way to adjust any of these settings is with your browser through
+the special Privoxy editor at http://config.privoxy.org/show-status (shortcut:
+http://p.p/show-status). This is an internal page, and does not require
+Internet access. Select the appropriate "actions" file, and click "Edit". It is
+best to put personal or local preferences in user.action since this is not
+meant to be overwritten during upgrades, and will over-ride the settings in
+other files. Here you can insert new "actions", and URLs for ad blocking or
+other purposes, and make other adjustments to the configuration. Privoxy will
+detect these changes automatically.
+
+A quick and simple step by step example:
+
+ * Right click on the ad image to be blocked, then select "Copy Link Location"
+ from the pop-up menu.
+
+ * Set your browser to http://config.privoxy.org/show-status
+
+ * Find user.action in the top section, and click on "Edit":
+
+ Figure 1. Actions Files in Use
+
+ [files-in-u]
+
+ * You should have a section with only block listed under "Actions:". If not,
+ click a "Insert new section below" button, and in the new section that just
+ appeared, click the Edit button right under the word "Actions:". This will
+ bring up a list of all actions. Find block near the top, and click in the
+ "Enabled" column, then "Submit" just below the list.
+
+ * Now, in the block actions section, click the "Add" button, and paste the
+ URL the browser got from "Copy Link Location". Remove the http:// at the
+ beginning of the URL. Then, click "Submit" (or "OK" if in a pop-up window).
+
+ * Now go back to the original page, and press SHIFT-Reload (or flush all
+ browser caches). The image should be gone now.
+
+This is a very crude and simple example. There might be good reasons to use a
+wildcard pattern match to include potentially similar images from the same
+site. For a more extensive explanation of "patterns", and the entire actions
+concept, see the Actions section.
+
+For advanced users who want to hand edit their config files, you might want to
+now go to the Actions Files Tutorial. The ideas explained therein also apply to
+the web-based editor.
+
-------------------------------------------------------------------------------
5. Starting Privoxy
Before launching Privoxy for the first time, you will want to configure your
-browser(s) to use Privoxy as a HTTP and HTTPS proxy. The default is localhost
-for the proxy address, and port 8118 (earlier versions used port 8000). This is
-the one configuration step that must be done!
+browser(s) to use Privoxy as a HTTP and HTTPS (SSL) proxy. The default is
+127.0.0.1 (or localhost) for the proxy address, and port 8118 (earlier versions
+used port 8000). This is the one configuration step that must be done!
+
+Please note that Privoxy can only proxy HTTP and HTTPS traffic. It will not
+work with FTP or other protocols.
+
+Figure 2. Proxy Configuration Showing Mozilla/Netscape HTTP and HTTPS (SSL)
+Settings
+
+[proxy_setu]
+
+With Firefox, this can be set under:
+
+ Tools -> Options -> General -> Connection Settings -> Manual Proxy
+Configuration
+
-With Netscape (and Mozilla), this can be set under Edit -> Preferences ->
-Advanced -> Proxies -> HTTP Proxy. For Internet Explorer: Tools -> Internet
-Properties -> Connections -> LAN Setting. Then, check "Use Proxy" and fill in
-the appropriate info (Address: localhost, Port: 8118). Include if HTTPS proxy
-support too.
+With Netscape (and Mozilla), this can be set under:
+
+ Edit -> Preferences -> Advanced -> Proxies -> HTTP Proxy
+
+
+For Internet Explorer v.5-6:
+
+ Tools -> Internet Options -> Connections -> LAN Settings
+
+Then, check "Use Proxy" and fill in the appropriate info (Address: 127.0.0.1,
+Port: 8118). Include HTTPS (SSL), if you want HTTPS proxy support too
+(sometimes labeled "Secure"). Make sure any checkboxes like "Use the same proxy
+server for all protocols" is UNCHECKED. You want only HTTP and HTTPS (SSL)!
+
+Figure 3. Proxy Configuration Showing Internet Explorer HTTP and HTTPS (Secure)
+Settings
+
+[proxy2]
After doing this, flush your browser's disk and memory caches to force a
-re-reading of all pages and to get rid of any ads that may be cached. You are
-now ready to start enjoying the benefits of using Privoxy!
+re-reading of all pages and to get rid of any ads that may be cached. Remove
+any cookies, if you want Privoxy to manage that. You are now ready to start
+enjoying the benefits of using Privoxy!
-Privoxy is typically started by specifying the main configuration file to be
-used on the command line. If no configuration file is specified on the command
-line, Privoxy will look for a file named config in the current directory.
-Except on Win32 where it will try config.txt.
+Privoxy itself is typically started by specifying the main configuration file
+to be used on the command line. If no configuration file is specified on the
+command line, Privoxy will look for a file named config in the current
+directory. Except on Win32 where it will try config.txt.
-------------------------------------------------------------------------------
-5.1. RedHat and Debian
+5.1. Red Hat, Fedora and Conectiva
-We use a script. Note that RedHat does not start Privoxy upon booting per
-default. It will use the file /etc/privoxy/config as its main configuration
-file. FIXME: Debian??
+A default Red Hat installation may not start Privoxy upon boot. It will use the
+file /etc/privoxy/config as its main configuration file.
# /etc/rc.d/init.d/privoxy start
+Or ...
+
+ # service privoxy start
+
+-------------------------------------------------------------------------------
+
+5.2. Debian
+
+We use a script. Note that Debian typically starts Privoxy upon booting per
+default. It will use the file /etc/privoxy/config as its main configuration
+file.
+
+ # /etc/init.d/privoxy start
+
-------------------------------------------------------------------------------
-5.2. SuSE
+5.3. SuSE
We use a script. It will use the file /etc/privoxy/config as its main
configuration file. Note that SuSE starts Privoxy upon booting your PC.
-------------------------------------------------------------------------------
-5.3. Windows
+5.4. Windows
Click on the Privoxy Icon to start Privoxy. If no configuration file is
specified on the command line, Privoxy will look for a file named config.txt.
-Note that Windows will automatically start Privoxy upon booting you PC.
+Note that Windows will automatically start Privoxy when the system starts if
+you chose that option when installing.
+
+Privoxy can run with full Windows service functionality. On Windows only, the
+Privoxy program has two new command line arguments to install and uninstall
+Privoxy as a service. See the Windows Installation instructions for details.
-------------------------------------------------------------------------------
-5.4. Solaris, NetBSD, FreeBSD, HP-UX and others
+5.5. Solaris, NetBSD, FreeBSD, HP-UX and others
Example Unix startup command:
-------------------------------------------------------------------------------
-5.5. OS/2
+5.6. OS/2
+
+During installation, Privoxy is configured to start automatically when the
+system restarts. You can start it manually by double-clicking on the Privoxy
+icon in the Privoxy folder.
+
+-------------------------------------------------------------------------------
+
+5.7. Mac OSX
+
+During installation, Privoxy is configured to start automatically when the
+system restarts. To start Privoxy manually, double-click on the
+StartPrivoxy.command icon in the /Library/Privoxy folder. Or, type this command
+in the Terminal:
+
+ /Library/Privoxy/StartPrivoxy.command
+
-FIXME.
+You will be prompted for the administrator password.
-------------------------------------------------------------------------------
-5.6. MAX OSX
+5.8. AmigaOS
-FIXME.
+Start Privoxy (with RUN <>NIL:) in your startnet script (AmiTCP), in s:
+user-startup (RoadShow), as startup program in your startup script (Genesis),
+or as startup action (Miami and MiamiDx). Privoxy will automatically quit when
+you quit your TCP/IP stack (just ignore the harmless warning your TCP/IP stack
+may display that Privoxy is still running).
-------------------------------------------------------------------------------
-5.7. AmigaOS
+5.9. Gentoo
+
+A script is again used. It will use the file /etc/privoxy/config as its main
+configuration file.
+
+ /etc/init.d/privoxy start
+
+
+Note that Privoxy is not automatically started at boot time by default. You can
+change this with the rc-update command.
-FIXME.
+ rc-update add privoxy default
+
-------------------------------------------------------------------------------
-5.8. Command Line Options
+5.10. Command Line Options
Privoxy may be invoked with the following command-line options:
included the GID of GROUP. Exit if the privileges are not sufficient to do
so. Unix only.
+ * --chroot
+
+ Before changing to the user ID given in the --user option, chroot to that
+ user's home directory, i.e. make the kernel pretend to the Privoxy process
+ that the directory tree starts there. If set up carefully, this can limit
+ the impact of possible vulnerabilities in Privoxy to the files contained in
+ that hierarchy. Unix only.
+
* configfile
If no configfile is included on the command line, Privoxy will look for a
look for "config.txt" instead). Specify full path to avoid confusion. If no
config file is found, Privoxy will fail to start.
+On MS Windows only there are two additional command-line options to allow
+Privoxy to install and run as a service. See the Window Installation section
+for details.
+
-------------------------------------------------------------------------------
6. Privoxy Configuration
config.privoxy.org/ (shortcut: http://p.p/), which is a built-in page and works
without Internet access. You will see the following section:
- Privoxy Menu
+ Privoxy Menu
? View & change the current configuration
? View the source code version numbers
? View the request headers.
? Look up which actions apply to a URL and why
? Toggle Privoxy on or off
+ ? Documentation
This should be self-explanatory. Note the first item leads to an editor for the
Multiple actions files may be defined in config. These are processed in the
order they are defined. Local customizations and locally preferred
exceptions to the default policies as defined in default.action (which you
- will most propably want to define sooner or later) are probably best
+ will most probably want to define sooner or later) are probably best
applied in user.action, where you can preserve them across upgrades.
standard.action is for Privoxy's internal use.
config.privoxy.org/show-status (Shortcut: http://p.p/show-status) for the
various actions files.
- * default.filter (the filter file) can be used to re-write the raw page
+ * "Filter files" (the filter file) can be used to re-write the raw page
content, including viewable text as well as embedded HTML and JavaScript,
and whatever else lurks on any given web page. The filtering jobs are only
pre-defined here; whether to apply them or not is up to the actions files.
-
+ default.filter includes various filters made available for use by the
+ developers. Some are much more intrusive than others, and all should be
+ used with caution. You may define additional filter files in config as you
+ can with actions files. We suggest user.filter for any locally defined
+ filters or customizations.
+
+The syntax of all configuration files has remained the same throughout the 3.x
+series. There have been enhancements, but no changes that would preclude the
+use of any configuration file from one version to the next. (There is one
+exception: +fast-redirects which has enhanced syntax and will require updating
+any local configs from earlier versions.)
+
All files use the "#" character to denote a comment (the rest of the line will
be ignored) and understand line continuation through placing a backslash ("\")
as the very last character in a line. If the # is preceded by a backslash, it
looses its special function. Placing a # in front of an otherwise valid
configuration line to prevent it from being interpreted is called "commenting
-out" that line.
+out" that line. Blank lines are ignored.
-The actions files and default.filter can use Perl style regular expressions for
+The actions files and filter files can use Perl style regular expressions for
maximum flexibility.
After making any changes, there is no need to restart Privoxy in order for the
-------------------------------------------------------------------------------
-7.1. Configuration and Log File Locations
+7.1. Local Set-up Documentation
+
+If you intend to operate Privoxy for more users than just yourself, it might be
+a good idea to let them know how to reach you, what you block and why you do
+that, your policies, etc.
+
+-------------------------------------------------------------------------------
+
+7.1.1. user-manual
+
+Specifies:
+
+ Location of the Privoxy User Manual.
+
+Type of value:
+
+ A fully qualified URI
+
+Default value:
+
+ Unset
+
+Effect if unset:
+
+ http://www.privoxy.org/version/user-manual/ will be used, where version is
+ the Privoxy version.
+
+Notes:
+
+ The User Manual URI is the single best source of information on Privoxy,
+ and is used for help links from some of the internal CGI pages. The manual
+ itself is normally packaged with the binary distributions, so you probably
+ want to set this to a locally installed copy.
+
+ Examples:
+
+ The best all purpose solution is simply to put the full local PATH to where
+ the User Manual is located:
+
+ user-manual /usr/share/doc/privoxy/user-manual
+
+ The User Manual is then available to anyone with access to the proxy, by
+ following the built-in URL: http://config.privoxy.org/user-manual/ (or the
+ shortcut: http://p.p/user-manual/).
+
+ If the documentation is not on the local system, it can be accessed from a
+ remote server, as:
+
+ user-manual http://example.com/privoxy/user-manual/
+
+ +-----------------------------------------------------------------+
+ | Warning |
+ |-----------------------------------------------------------------|
+ |If set, this option should be the first option in the config |
+ |file, because it is used while the config file is being read on |
+ |start-up. |
+ +-----------------------------------------------------------------+
+
+-------------------------------------------------------------------------------
+
+7.1.2. trust-info-url
+
+Specifies:
+
+ A URL to be displayed in the error page that users will see if access to an
+ untrusted page is denied.
+
+Type of value:
+
+ URL
+
+Default value:
+
+ Two example URL are provided
+
+Effect if unset:
+
+ No links are displayed on the "untrusted" error page.
+
+Notes:
+
+ The value of this option only matters if the experimental trust mechanism
+ has been activated. (See trustfile above.)
+
+ If you use the trust mechanism, it is a good idea to write up some on-line
+ documentation about your trust policy and to specify the URL(s) here. Use
+ multiple times for multiple URLs.
+
+ The URL(s) should be added to the trustfile as well, so users don't end up
+ locked out from the information on why they were locked out in the first
+ place!
+
+-------------------------------------------------------------------------------
+
+7.1.3. admin-address
+
+Specifies:
+
+ An email address to reach the proxy administrator.
+
+Type of value:
+
+ Email address
+
+Default value:
+
+ Unset
+
+Effect if unset:
+
+ No email address is displayed on error pages and the CGI user interface.
+
+Notes:
+
+ If both admin-address and proxy-info-url are unset, the whole "Local
+ Privoxy Support" box on all generated pages will not be shown.
+
+-------------------------------------------------------------------------------
+
+7.1.4. proxy-info-url
+
+Specifies:
+
+ A URL to documentation about the local Privoxy setup, configuration or
+ policies.
+
+Type of value:
+
+ URL
+
+Default value:
+
+ Unset
+
+Effect if unset:
+
+ No link to local documentation is displayed on error pages and the CGI user
+ interface.
+
+Notes:
+
+ If both admin-address and proxy-info-url are unset, the whole "Local
+ Privoxy Support" box on all generated pages will not be shown.
+
+ This URL shouldn't be blocked ;-)
+
+-------------------------------------------------------------------------------
+
+7.2. Configuration and Log File Locations
Privoxy can (and normally does) use a number of other files for additional
configuration, help and logging. This section of the configuration file tells
The user running Privoxy, must have read permission for all configuration
files, and write permission to any files that would be modified, such as log
-files.
+files and actions files.
-------------------------------------------------------------------------------
-7.1.1. confdir
+7.2.1. confdir
Specifies:
No trailing "/", please
- When development goes modular and multi-user, the blocker, filter, and
- per-user config will be stored in subdirectories of "confdir". For now, the
- configuration directory structure is flat, except for confdir/templates,
- where the HTML templates for CGI output reside (e.g. Privoxy's 404 error
- page).
-
-------------------------------------------------------------------------------
-7.1.2. logdir
+7.2.2. logdir
Specifies:
-------------------------------------------------------------------------------
-7.1.3. actionsfile
+7.2.3. actionsfile
Specifies:
File name, relative to confdir, without the .action suffix
-Default value:
+Default values:
standard # Internal purposes, no editing recommended
-------------------------------------------------------------------------------
-7.1.4. filterfile
+7.2.4. filterfile
Specifies:
- The filter file to use
+ The filter file(s) to use
Type of value:
Notes:
- The "default.filter" file contains content modification rules that use
- "regular expressions". These rules permit powerful changes on the content
- of Web pages, e.g., you could disable your favorite JavaScript annoyances,
- re-write the actual displayed text, or just have some fun replacing
- "Microsoft" with "MicroSuck" wherever it appears on a Web page.
+ Multiple filterfile lines are permitted.
+
+ The filter files contain content modification rules that use regular
+ expressions. These rules permit powerful changes on the content of Web
+ pages, and optionally the headers as well, e.g., you could disable your
+ favorite JavaScript annoyances, re-write the actual displayed text, or just
+ have some fun playing buzzword bingo with web pages.
+
+ The +filter{name} actions rely on the relevant filter (name) to be defined
+ in a filter file!
+
+ A pre-defined filter file called default.filter that contains a number of
+ useful filters for common problems is included in the distribution. See the
+ section on the filter action for a list.
+
+ It is recommended to place any locally adapted filters into a separate
+ file, such as user.filter.
-------------------------------------------------------------------------------
-7.1.5. logfile
+7.2.5. logfile
Specifies:
Effect if unset:
- No log file is used, all log messages go to the console (stderr).
+ No log file is used, all log messages go to the console (STDERR).
Notes:
- The windows version will additionally log to the console.
-
The logfile is where all logging and error messages are written. The level
of detail and number of messages are set with the debug option (see below).
The logfile can be useful for tracking down a problem with Privoxy (e.g.,
-------------------------------------------------------------------------------
-7.1.6. jarfile
+7.2.6. jarfile
Specifies:
Default value:
- jarfile (Unix) or privoxy.jar (Windows)
+ Unset (commented out). When activated: jarfile (Unix) or privoxy.jar
+ (Windows)
Effect if unset:
- Intercepted cookies are not stored at all.
+ Intercepted cookies are not stored in a dedicated log file.
Notes:
The jarfile may grow to ridiculous sizes over time.
+ If debug 8 (show header parsing) is enabled, cookies are written to the
+ logfile with the rest of the headers.
+
-------------------------------------------------------------------------------
-7.1.7. trustfile
+7.2.7. trustfile
Specifies:
- The trust file to use
+ The name of the trust file to use
Type of value:
Effect if unset:
- The whole trust mechanism is turned off.
+ The entire trust mechanism is disabled.
Notes:
should be used with care. It is NOT recommended for the casual user.
If you specify a trust file, Privoxy will only allow access to sites that
- are named in the trustfile. You can also mark sites as trusted referrers
- (with +), with the effect that access to untrusted sites will be granted,
- if a link from a trusted referrer was used. The link target will then be
- added to the "trustfile". Possible applications include limiting Internet
- access for children.
-
- If you use + operator in the trust file, it may grow considerably over
+ are specified in the trustfile. Sites can be listed in one of two ways:
+
+ Prepending a ~ character limits access to this site only (and any sub-paths
+ within this site), e.g. ~www.example.com allows access to ~www.example.com/
+ features/news.html, etc.
+
+ Or, you can designate sites as trusted referrers, by prepending the name
+ with a + character. The effect is that access to untrusted sites will be
+ granted -- but only if a link from this trusted referrer was used to get
+ there. The link target will then be added to the "trustfile" so that
+ future, direct accesses will be granted. Sites added via this mechanism do
+ not become trusted referrers themselves (i.e. they are added with a ~
+ designation). There is a limit of 512 such entries, after which new entries
+ will not be made.
+
+ If you use the + operator in the trust file, it may grow considerably over
time.
--------------------------------------------------------------------------------
-
-7.2. Local Set-up Documentation
-
-If you intend to operate Privoxy for more users that just yourself, it might be
-a good idea to let them know how to reach you, what you block and why you do
-that, your policies etc.
-
--------------------------------------------------------------------------------
-
-7.2.1. user-manual
-
-Specifies:
-
- Location of the Privoxy User Manual.
-
-Type of value:
-
- A fully qualified URI
-
-Default value:
-
- Unset
-
-Effect if unset:
-
- http://www.privoxy.org/version/user-manual/ will be used, where version is
- the Privoxy version.
-
-Notes:
-
- The User Manual URI is used for help links from some of the internal CGI
- pages. The manual itself is normally packaged with the binary
- distributions, so you propably want to set this to a locally installed
- copy. For multi-user setups, you could provide a copy on a local webserver
- for all your users and use the corresponding URL here.
-
- Examples:
-
- Unix, in local filesystem:
-
- user-manual file:///usr/share/doc/privoxy-2.9.14/user-manual/
-
- Any platform, on local webserver (called "local-webserver"):
-
- user-manual http://local-webserver/privoxy-user-manual/
-
- +-----------------------------------------------------------------+
- | Warning |
- |-----------------------------------------------------------------|
- |If set, this option should be the first option in the config |
- |file, because it is used while the config file is being read. |
- +-----------------------------------------------------------------+
-
--------------------------------------------------------------------------------
-
-7.2.2. trust-info-url
-
-Specifies:
-
- A URL to be displayed in the error page that users will see if access to an
- untrusted page is denied.
-
-Type of value:
-
- URL
-
-Default value:
-
- Two example URL are provided
-
-Effect if unset:
-
- No links are displayed on the "untrusted" error page.
-
-Notes:
-
- The value of this option only matters if the experimental trust mechanism
- has been activated. (See trustfile above.)
-
- If you use the trust mechanism, it is a good idea to write up some on-line
- documentation about your trust policy and to specify the URL(s) here. Use
- multiple times for multiple URLs.
-
- The URL(s) should be added to the trustfile as well, so users don't end up
- locked out from the information on why they were locked out in the first
- place!
-
--------------------------------------------------------------------------------
-
-7.2.3. admin-address
-
-Specifies:
-
- An email address to reach the proxy administrator.
-
-Type of value:
-
- Email address
-
-Default value:
-
- Unset
-
-Effect if unset:
-
- No email address is displayed on error pages and the CGI user interface.
-
-Notes:
-
- If both admin-address and proxy-info-url are unset, the whole "Local
- Privoxy Support" box on all generated pages will not be shown.
-
--------------------------------------------------------------------------------
-
-7.2.4. proxy-info-url
-
-Specifies:
-
- A URL to documentation about the local Privoxy setup, configuration or
- policies.
-
-Type of value:
-
- URL
-
-Default value:
-
- Unset
-
-Effect if unset:
-
- No link to local documentation is displayed on error pages and the CGI user
- interface.
-
-Notes:
-
- If both admin-address and proxy-info-url are unset, the whole "Local
- Privoxy Support" box on all generated pages will not be shown.
+ It is recommended that Privoxy be compiled with the --disable-force,
+ --disable-toggle and --disable-editor options, if this feature is to be
+ used.
- This URL shouldn't be blocked ;-)
+ Possible applications include limiting Internet access for children.
-------------------------------------------------------------------------------
Specifies:
- Key values that determine what information gets logged.
+ Key values that determine what information gets logged to the logfile.
Type of value:
debug 256 # debug GIF de-animation
debug 512 # Common Log Format
debug 1024 # debug kill pop-ups
+ debug 2048 # CGI user interface
debug 4096 # Startup banner and warnings.
debug 8192 # Non-fatal errors
Default value:
- localhost:8118
+ 127.0.0.1:8118
Effect if unset:
- Bind to localhost (127.0.0.1), port 8118. This is suitable and recommended
+ Bind to 127.0.0.1 (localhost), port 8118. This is suitable and recommended
for home users who run Privoxy on the same machine as their browser.
Notes:
If you leave out the IP address, Privoxy will bind to all interfaces
(addresses) on your machine and may become reachable from the Internet. In
- that case, consider using access control lists (ACL's) (see "ACLs" below),
- or a firewall.
+ that case, consider using access control lists (ACL's, see below), and/or a
+ firewall.
+
+ If you open Privoxy to untrusted users, you will also want to turn off the
+ enable-edit-actions and enable-remote-toggle options!
Example:
Notes:
If set to 0, Privoxy will start in "toggled off" mode, i.e. behave like a
- normal, content-neutral proxy. See enable-remote-toggle below. This is not
- really useful anymore, since toggling is much easier via the web interface
- than via editing the conf file.
+ normal, content-neutral proxy where all ad blocking, filtering, etc are
+ disabled. See enable-remote-toggle below. This is not really useful
+ anymore, since toggling is much easier via the web interface than via
+ editing the conf file.
The windows version will only display the toggle icon in the system tray if
this option is present.
-------------------------------------------------------------------------------
-7.4.4. enable-edit-actions
+7.4.4. enable-remote-http-toggle
+
+Specifies:
+
+ Whether or not Privoxy recognizes special HTTP headers to change its
+ behaviour.
+
+Type of value:
+
+ 0 or 1
+
+Default value:
+
+ 1
+
+Effect if unset:
+
+ Privoxy ignores special HTTP headers.
+
+Notes:
+
+ When toggled on, the client can change Privoxy's behaviour by setting
+ special HTTP headers. Currently the only supported special header is
+ "X-Filter: No", to disable filtering for the ongoing request, even if it is
+ enabled in one of the action files.
+
+ If you are using Privoxy in a multi-user environment or with untrustworthy
+ clients and want to enforce filtering, you will have to disable this
+ option, otherwise you can ignore it.
+
+-------------------------------------------------------------------------------
+
+7.4.5. enable-edit-actions
Specifies:
-------------------------------------------------------------------------------
-7.4.5. ACLs: permit-access and deny-access
+7.4.6. ACLs: permit-access and deny-access
Specifies:
Access controls are included at the request of ISPs and systems
administrators, and are not usually needed by individual users. For a
typical home user, it will normally suffice to ensure that Privoxy only
- listens on the localhost or internal (home) network address by means of the
- listen-address option.
+ listens on the localhost (127.0.0.1) or internal (home) network address by
+ means of the listen-address option.
Please see the warnings in the FAQ that this proxy is not intended to be a
substitute for a firewall or to encourage anyone to defer addressing basic
-------------------------------------------------------------------------------
-7.4.6. buffer-limit
+7.4.7. buffer-limit
Specifies:
This feature allows routing of HTTP requests through a chain of multiple
proxies. It can be used to better protect privacy and confidentiality when
accessing specific domains by routing requests to those domains through an
-anonymous public proxy (see e.g. http://www.multiproxy.org/anon_list.htm) Or to
-use a caching proxy to speed up browsing. Or chaining to a parent proxy may be
-necessary because the machine that Privoxy runs on has no direct Internet
-access.
+anonymous public proxy. Or to use a caching proxy to speed up browsing. Or
+chaining to a parent proxy may be necessary because the machine that Privoxy
+runs on has no direct Internet access.
Also specified here are SOCKS proxies. Privoxy supports the SOCKS 4 and SOCKS
4A protocols.
Type of value:
- target_domain[:port] http_parent[/port]
+ target_pattern http_parent[:port]
- Where target_domain is a domain name pattern (see the chapter on domain
- matching in the default.action file), http_parent is the address of the
- parent HTTP proxy as an IP addresses in dotted decimal notation or as a
- valid DNS name (or "." to denote "no forwarding", and the optional port
- parameters are TCP ports, i.e. integer values from 1 to 64535
+ where target_pattern is a URL pattern that specifies to which requests
+ (i.e. URLs) this forward rule shall apply. Use / to denote "all URLs".
+ http_parent[:port] is the DNS name or IP address of the parent HTTP proxy
+ through which the requests should be forwarded, optionally followed by its
+ listening port (default: 8080). Use a single dot (.) to denote "no
+ forwarding".
Default value:
Everything goes to an example anonymizing proxy, except SSL on port 443
(which it doesn't handle):
- forward .* anon-proxy.example.org:8080
+ forward / anon-proxy.example.org:8080
forward :443 .
Everything goes to our example ISP's caching proxy, except for requests to
that ISP's sites:
- forward .*. caching-proxy.example-isp.net:8000
+ forward / caching-proxy.example-isp.net:8000
forward .example-isp.net .
-------------------------------------------------------------------------------
Type of value:
- target_domain[:port] socks_proxy[/port] http_parent[/port]
+ target_pattern socks_proxy[:port] http_parent[:port]
- Where target_domain is a domain name pattern (see the chapter on domain
- matching in the default.action file), http_parent and socks_proxy are IP
- addresses in dotted decimal notation or valid DNS names (http_parent may be
- "." to denote "no HTTP forwarding"), and the optional port parameters are
- TCP ports, i.e. integer values from 1 to 64535
+ where target_pattern is a URL pattern that specifies to which requests
+ (i.e. URLs) this forward rule shall apply. Use / to denote "all URLs".
+ http_parent and socks_proxy are IP addresses in dotted decimal notation or
+ valid DNS names (http_parent may be "." to denote "no HTTP forwarding"),
+ and the optional port parameters are TCP ports, i.e. integer values from 1
+ to 64535
Default value:
domains, but everything outbound goes through their ISP's proxy by way of
example.com's corporate SOCKS 4A gateway to the Internet.
- forward-socks4a .*. socks-gw.example.com:1080 www-cache.example-isp.net:8080
+ forward-socks4a / socks-gw.example.com:1080 www-cache.example-isp.net:8080
forward .example.com .
A rule that uses a SOCKS 4 gateway for all destinations but no HTTP parent
looks like this:
- forward-socks4 .*. socks-gw.example.com:1080 .
+ forward-socks4 / socks-gw.example.com:1080 .
+
+ To chain Privoxy and Tor, both running on the same system, you should use
+ the rule:
+
+ forward-socks4 / 127.0.0.1:9050 .
+
+ The public Tor network can't be used to reach your local network, therefore
+ it's a good idea to make some exceptions:
+
+ forward 192.168.*.*/ .
+ forward 10.*.*.*/ .
+ forward 127.*.*.*/ .
+
+ Unencrypted connections to systems in these address ranges will be as (un)
+ secure as the local network is, but the alternative is that you can't reach
+ the network at all.
+
+ If you also want to be able to reach servers in your local network by using
+ their names, you will need additional exceptions that look like this:
+
+ forward localhost/ .
-------------------------------------------------------------------------------
host-a:
- forward .*. .
+ forward / .
forward .isp-b.net host-b:8118
host-b:
- forward .*. .
+ forward / .
forward .isp-a.net host-a:8118
Now, your users can set their browser's proxy to use either host-a or host-b
and port. Squid normally uses port 3128. If unsure consult http_port in
squid.conf.
+You could just as well decide to only forward requests for Windows executables
+through a virus-scanning parent proxy, say, on antivir.example.com, port 8010:
+
+ forward / .
+ forward /.*\.(exe|com|dll|zip)$ antivir.example.com:8010
+
+-------------------------------------------------------------------------------
+
+7.5.4. forwarded-connect-retries
+
+Specifies:
+
+ How often Privoxy retries if a forwarded connection request fails.
+
+Type of value:
+
+ Number of retries.
+
+Default value:
+
+ 0
+
+Effect if unset:
+
+ Forwarded connections are treated like direct connections and no retry
+ attempts are made.
+
+Notes:
+
+ forwarded-connect-retries is mainly interesting for socks4a connections,
+ where Privoxy can't detect why the connections failed. The connection might
+ have failed because of a DNS timeout in which case a retry makes sense, but
+ it might also have failed because the server doesn't exist or isn't
+ reachable. In this case the retry will just delay the appearance of
+ Privoxy's error message.
+
+ Only use this option, if you are getting many forwarding related error
+ messages, that go away when you try again manually. Start with a small
+ value and check Privoxy's logfile from time to time, to see how many
+ retries are usually needed.
+
+Examples:
+
+ forwarded-connect-retries 1
+
-------------------------------------------------------------------------------
7.6. Windows GUI Options
8. Actions Files
The actions files are used to define what actions Privoxy takes for which URLs,
-and thus determine how ad images, cookies and various other aspects of HTTP
+and thus determines how ad images, cookies and various other aspects of HTTP
content and transactions are handled, and on which sites (or even parts
-thereof). There are three such files included with Privoxy (as of version
-2.9.15), with differing purposes:
+thereof). There are a number of such actions, with a wide range of
+functionality. Each action does something a little different. These actions
+give us a veritable arsenal of tools with which to exert our control,
+preferences and independence. Actions can be combined so that their effects are
+aggregated when applied against a given set of URLs.
+
+There are three action files included with Privoxy with differing purposes:
- * standard.action - is used by the web based editor, to set various
- pre-defined sets of rules for the default actions section in
- default.action. These have increasing levels of aggressiveness and have no
- influence on your browsing unless you select them explicitly in the editor.
- It is not recommend to edit this file.
-
* default.action - is the primary action file that sets the initial values
for all actions. It is intended to provide a base level of functionality
for Privoxy's array of features. So it is a set of broad rules that should
- work reasonably well for users everywhere. This is the file that the
- developers are keeping updated, and making available to users.
+ work reasonably well as-is for most users. This is the file that the
+ developers are keeping updated, and making available to users. The user's
+ preferences as set in standard.action, e.g. either Cautious (the default),
+ Medium, or Advanced (see below).
* user.action - is intended to be for local site preferences and exceptions.
As an example, if your ISP or your bank has specific requirements, and need
special handling, this kind of thing should go here. This file will not be
upgraded.
+ * standard.action - is used by the web based editor at http://
+ config.privoxy.org/edit-actions-list?f=default, to set various pre-defined
+ sets of rules for the default actions section in default.action.
+
+ Edit Set to Cautious Set to Medium Set to Advanced
+
+ These have increasing levels of aggressiveness and have no influence on
+ your browsing unless you select them explicitly in the editor. A default
+ installation should be pre-set to Cautious (versions prior to 3.0.5 were
+ set to Medium). New users should try this for a while before adjusting the
+ settings to more aggressive levels.
+
+ The Edit button allows you to turn each action on/off individually for
+ fine-tuning. The Cautious button changes the actions list to low/safe
+ settings which will activate a minimal set of Privoxy's features, and
+ subsequently there will be less of a chance for accidental problems. The
+ Medium button sets the list to a medium level of ad blocking and a low
+ level set of privacy features. The Advanced button sets the list to a high
+ level of ad blocking and medium level of privacy. See the chart below. The
+ latter three buttons over-ride any changes via with the Edit button. More
+ fine-tuning can be done in the lower sections of this internal page.
+
+ It is not recommend to edit the standard.action file itself.
+
+ The default profiles, and their associated actions, as pre-defined in
+ standard.action are:
+
+ Table 1. Default Configurations
+
+ +-------------------------------------------------------------------------+
+ |Feature |Cautious |Medium |Advanced |
+ |------------------+-----------------+------------------+-----------------|
+ |Ad-blocking |medium |high |high |
+ |Aggressiveness | | | |
+ |------------------+-----------------+------------------+-----------------|
+ |Ad-filtering by |no |yes |yes |
+ |size | | | |
+ |------------------+-----------------+------------------+-----------------|
+ |Ad-filtering by |no |no |yes |
+ |link | | | |
+ |------------------+-----------------+------------------+-----------------|
+ |Pop-up killing |blocks only |blocks only |all |
+ |------------------+-----------------+------------------+-----------------|
+ |Privacy Features |low |medium |medium/high |
+ |------------------+-----------------+------------------+-----------------|
+ |Cookie handling |none |session-only |kill |
+ |------------------+-----------------+------------------+-----------------|
+ |Referer forging |no |yes |yes |
+ |------------------+-----------------+------------------+-----------------|
+ |GIF de-animation |no |yes |yes |
+ |------------------+-----------------+------------------+-----------------|
+ |Fast redirects |no |no |yes |
+ |------------------+-----------------+------------------+-----------------|
+ |HTML taming |no |yes |yes |
+ |------------------+-----------------+------------------+-----------------|
+ |JavaScript taming |no |yes |yes |
+ |------------------+-----------------+------------------+-----------------|
+ |Web-bug killing |no |yes |yes |
+ |------------------+-----------------+------------------+-----------------|
+ |Image tag |no |no |yes |
+ |reordering | | | |
+ +-------------------------------------------------------------------------+
+
The list of actions files to be used are defined in the main configuration
-file, and are processed in the order they are defined. The content of these can
-all be viewed and edited from http://config.privoxy.org/show-status.
+file, and are processed in the order they are defined (e.g. default.action is
+typically process before user.action). The content of these can all be viewed
+and edited from http://config.privoxy.org/show-status. The over-riding
+principle when applying actions, is that the last action that matches a given
+URL, wins. The broadest, most general rules go first (defined in
+default.action), followed by any exceptions (typically also in default.action),
+which are then followed lastly by any local preferences (typically in
+user.action). Generally, user.action has the last word.
An actions file typically has multiple sections. If you want to use "aliases"
in an actions file, you have to place the (optional) alias section at the top
Note that some actions, like cookie suppression or script disabling, may render
some sites unusable that rely on these techniques to work properly. Finding the
right mix of actions is not always easy and certainly a matter of personal
-taste. In general, it can be said that the more "aggressive" your default
-settings (in the top section of the actions file) are, the more exceptions for
-"trusted" sites you will have to make later. If, for example, you want to kill
-popup windows per default, you'll have to make exceptions from that rule for
-sites that you regularly use and that require popups for actually useful
-content, like maybe your bank, favorite shop, or newspaper.
+taste. And, things can always change, requiring refinements in the
+configuration. In general, it can be said that the more "aggressive" your
+default settings (in the top section of the actions file) are, the more
+exceptions for "trusted" sites you will have to make later. If, for example,
+you want to crunch all cookies per default, you'll have to make exceptions from
+that rule for sites that you regularly use and that require cookies for
+actually useful purposes, like maybe your bank, favorite shop, or newspaper.
We have tried to provide you with reasonable rules to start from in the
distribution actions files. But there is no general rule of thumb on these
browser-based editor, which can be reached from http://config.privoxy.org/
show-status. The editor allows both fine-grained control over every single
feature on a per-URL basis, and easy choosing from wholesale sets of defaults
-like "Cautious", "Medium" or "Advanced".
+like "Cautious", "Medium" or "Advanced". Warning: the "Advanced" setting is
+more aggressive, and will be more likely to cause problems for some sites.
+Experienced users only!
If you prefer plain text editing to GUIs, you can of course also directly edit
-the the actions files. Look at default.action which is richly commented.
+the the actions files with your favorite text editor. Look at default.action
+which is richly commented with many good examples.
-------------------------------------------------------------------------------
on a separate line.
To determine which actions apply to a request, the URL of the request is
-compared to all patterns in each action file file. Every time it matches, the
+compared to all patterns in each "action file" file. Every time it matches, the
list of applicable actions for the URL is incrementally updated, using the
heading of the section in which the pattern is located. If multiple matches for
the same URL set the same action differently, the last match wins. If not, the
-effects are aggregated (e.g. a URL might match both the "+handle-as-image" and
-"+block" actions).
+effects are aggregated. E.g. a URL might match a regular section with a heading
+line of { +handle-as-image }, then later another one with just { +block },
+resulting in both actions to apply. And there may well be cases where you will
+want to combine actions together. Such a section then might look like:
+
+ { +handle-as-image +block }
+ # Block these as if they were images. Send no block page.
+ banners.example.com
+ media.example.com/.*banners
+ .example.com/images/ads/
You can trace this process for any given URL by visiting http://
config.privoxy.org/show-url-info.
-More detail on this is provided in the Appendix, Anatomy of an Action.
+Examples and more detail on this is provided in the Appendix, Troubleshooting:
+Anatomy of an Action section.
-------------------------------------------------------------------------------
8.4. Patterns
-Generally, a pattern has the form <domain>/<path>, where both the <domain> and
-<path> are optional. (This is why the pattern / matches all URLs).
+As mentioned, Privoxy uses "patterns" to determine what actions might apply to
+which sites and pages your browser attempts to access. These "patterns" use
+wild card type pattern matching to achieve a high degree of flexibility. This
+allows one expression to be expanded and potentially match against many similar
+patterns.
+
+Generally, a Privoxy pattern has the form <domain>/<path>, where both the
+<domain> and <path> are optional. (This is why the special / pattern matches
+all URLs). Note that the protocol portion of the URL pattern (e.g. http://)
+should not be included in the pattern. This is assumed already!
+
+The pattern matching syntax is different for the domain and path parts of the
+URL. The domain part uses a simple globbing type matching technique, while the
+path part uses a more flexible "Regular Expressions (PCRE)" based syntax.
www.example.com/
is a domain-only pattern and will match any request to www.example.com,
- regardless of which document on that server is requested.
+ regardless of which document on that server is requested. So ALL pages in
+ this domain would be covered by the scope of this action. Note that a
+ simple example.com is different and would NOT match.
www.example.com
/index.html
matches the document /index.html, regardless of the domain, i.e. on any web
- server.
+ server anywhere.
index.html
matches nothing, since it would be interpreted as a domain name and there
- is no top-level domain called .html.
+ is no top-level domain called .html. So its a mistake.
-------------------------------------------------------------------------------
.example.
- matches any domain that CONTAINS .example. (Correctly speaking: It matches
- any FQDN that contains example as a domain.)
+ matches any domain that CONTAINS .example.. And, by the way, also included
+ would be any files or documents that exist within that domain since no path
+ limitations are specified. (Correctly speaking: It matches any FQDN that
+ contains example as a domain.) This might be www.example.com,
+ news.example.de, or www.example.net/cgi/testing.pl for instance. All these
+ cases are matched.
Additionally, there are wild-cards that you can use in the domain names
-themselves. They work pretty similar to shell wild-cards: "*" stands for zero
-or more arbitrary characters, "?" stands for any single character, you can
-define character classes in square brackets and all of that can be freely
-mixed:
+themselves. These work similarly to shell globbing type wild-cards: "*"
+represents zero or more arbitrary characters (this is equivalent to the
+"Regular Expression" based syntax of ".*"), "?" represents any single character
+(this is equivalent to the regular expression syntax of a simple "."), and you
+can define "character classes" in square brackets which is similar to the same
+regular expression technique. All of this can be freely mixed:
ad*.example.com
matches www1.example.com, www4.example.cc, wwwd.example.cy,
wwwz.example.com etc., but not wwww.example.com.
+While flexibile, this is not the sophistication of full regular expression
+based syntax.
+
-------------------------------------------------------------------------------
8.4.2. The Path Pattern
-Privoxy uses Perl compatible regular expressions (through the PCRE library) for
-matching the path.
+Privoxy uses Perl compatible (PCRE) "Regular Expression" based syntax (through
+the PCRE library) for matching the path portion (after the slash), and is thus
+more flexible.
There is an Appendix with a brief quick-start into regular expressions, and
full (very technical) documentation on PCRE regex syntax is available on-line
at http://www.pcre.org/man.txt. You might also find the Perl man page on
regular expressions (man perlre) useful, which is available on-line at http://
-www.perldoc.com/perl5.6/pod/perlre.html.
+perldoc.perl.org/perlre.html.
Note that the path pattern is automatically left-anchored at the "/", i.e. it
matches as if it would start with a "^" (regular expression speak for the
beginning of a line).
-Please also note that matching in the path is case INSENSITIVE by default, but
+Please also note that matching in the path is CASE INSENSITIVE by default, but
you can switch to case sensitive at any point in the pattern by using the "(?
-i)" switch: www.example.com/(?-i)PaTtErN.* will match only documents whose
path starts with PaTtErN in exactly this capitalization.
+.example.com/.*
+
+ Is equivalent to just ".example.com", since any documents within that
+ domain are matched with or without the ".*" regular expression. This is
+ redundant
+
+.example.com/.*/index.html
+
+ Will match any page in the domain of "example.com" that is named
+ "index.html", and that is part of some path. For example, it matches
+ "www.example.com/testing/index.html" but NOT "www.example.com/index.html"
+ because the regular expression called for at least two "/'s", thus the path
+ requirement. It also would match "www.example.com/testing/index_html",
+ because of the special meta-character ".".
+
+.example.com/(.*/)?index\.html
+
+ This regular expression is conditional so it will match any page named
+ "index.html" regardless of path which in this case can have one or more "/
+ 's". And this one must contain exactly ".html" (but does not have to end
+ with that!).
+
+.example.com/(.*/)(ads|banners?|junk)
+
+ This regular expression will match any path of "example.com" that contains
+ any of the words "ads", "banner", "banners" (because of the "?") or "junk".
+ The path does not have to end in these words, just contain them.
+
+.example.com/(.*/)(ads|banners?|junk)/.*\.(jpe?g|gif|png)$
+
+ This is very much the same as above, except now it must end in either
+ ".jpg", ".jpeg", ".gif" or ".png". So this one is limited to common image
+ formats.
+
+There are many, many good examples to be found in default.action, and more
+tutorials below in Appendix on regular expressions.
+
-------------------------------------------------------------------------------
8.5. Actions
they apply. Together, the actions line and the following pattern lines make up
a section of the actions file.
-There are three classes of actions:
+Actions fall into three categories:
* Boolean, i.e the action can only be "enabled" or "disabled". Syntax:
Later defined actions always over-ride earlier ones. So exceptions to any rules
you make, should come in the latter part of the file (or in a file that is
-processed later when using multiple actions files). For multi-valued actions,
-the actions are applied in the order they are specified. Actions files are
-processed in the order they are defined in config (the default installation has
-three actions files). It also quite possible for any given URL pattern to match
-more than one pattern and thus more than one set of actions!
+processed later when using multiple actions files such as user.action). For
+multi-valued actions, the actions are applied in the order they are specified.
+Actions files are processed in the order they are defined in config (the
+default installation has three actions files). It also quite possible for any
+given URL pattern to match more than one pattern and thus more than one set of
+actions! Last match wins.
The list of valid Privoxy actions are:
-------------------------------------------------------------------------------
-8.5.1. +add-header
+8.5.1. add-header
-Type:
+Typical use:
- Multi-value.
+ Confuse log analysis, custom applications
-Purpose and typical uses:
+Effect:
- Send a user defined HTTP header to the web server. Can be used to confuse
- log analysis.
+ Sends a user defined HTTP header to the web server.
-Possible values:
+Type:
- Any value is possible. Validity of the defined HTTP headers is not checked.
- It is recommended that you use the "X-" prefix for custom headers.
+ Multi-value.
-Example usage:
+Parameter:
- {+add-header{X-User-Tracking: sucks}}
- .example.com
+ Any string value is possible. Validity of the defined HTTP headers is not
+ checked. It is recommended that you use the "X-" prefix for custom headers.
Notes:
headers. This is rarely needed for the typical user. If you don't know what
"HTTP headers" are, you definitely don't need to worry about this one.
+Example usage:
+
+ +add-header{X-User-Tracking: sucks}
+
-------------------------------------------------------------------------------
-8.5.2. +block
+8.5.2. block
-Type:
+Typical use:
- Boolean.
+ Block ads or other unwanted content
-Purpose and typical uses:
+Effect:
Requests for URLs to which this action applies are blocked, i.e. the
- requests are not forwarded to the remote server, but answered locally with
- a substitute page or image, as determined by the handle-as-image and
- set-image-blocker actions. It is typically used to block ads or other
- obnoxious content.
+ requests are trapped by Privoxy and the requested URL is never retrieved,
+ but is answered locally with a substitute page or image, as determined by
+ the handle-as-image, set-image-blocker, and handle-as-empty-document
+ actions.
-Possible values:
+Type:
- N/A
+ Boolean.
-Example usage:
+Parameter:
- {+block}
- .banners.example.com
- .ads.r.us
-
+ N/A
Notes:
- If a URL matches one of the blocked patterns, Privoxy will intercept the
- URL and display its special "BLOCKED" page instead. If there is sufficient
- space, a large red banner will appear with a friendly message about why the
- page was blocked, and a way to go there anyway. If there is insufficient
- space a smaller "BLOCKED" page will appear without the red banner. Click
- here to view the default blocked HTML page (Privoxy must be running for
- this to work as intended!).
-
- A very important exception is if the URL matches both "+block" and
- "+handle-as-image", then it will be handled by "+set-image-blocker" (see
- below). It is important to understand this process, in order to understand
- how Privoxy is able to deal with ads and other objectionable content.
-
- The "+filter" action can also perform some of the same functionality as
- "+block", but by virtue of very different programming techniques, and is
- most often used for different reasons.
+ Privoxy sends a special "BLOCKED" page for requests to blocked pages. This
+ page contains links to find out why the request was blocked, and a
+ click-through to the blocked content (the latter only if compiled with the
+ force feature enabled). The "BLOCKED" page adapts to the available screen
+ space -- it displays full-blown if space allows, or miniaturized and
+ text-only if loaded into a small frame or window. If you are using Privoxy
+ right now, you can take a look at the "BLOCKED" page.
+
+ A very important exception occurs if both block and handle-as-image, apply
+ to the same request: it will then be replaced by an image. If
+ set-image-blocker (see below) also applies, the type of image will be
+ determined by its parameter, if not, the standard checkerboard pattern is
+ sent.
+
+ It is important to understand this process, in order to understand how
+ Privoxy deals with ads and other unwanted content. Blocking is a core
+ feature, and one upon which various other features depend.
+
+ The filter action can perform a very similar task, by "blocking" banner
+ images and other content through rewriting the relevant URLs in the
+ document's HTML source, so they don't get requested in the first place.
+ Note that this is a totally different technique, and it's easy to confuse
+ the two.
+
+Example usage (section):
+
+ {+block}
+ # Block and replace with "blocked" page
+ .nasty-stuff.example.com
+
+ {+block +handle-as-image}
+ # Block and replace with image
+ .ad.doubleclick.net
+ .ads.r.us/banners/
+
+ {+block +handle-as-empty-document}
+ # Block and then ignore
+ adserver.exampleclick.net/.*\.js$
-------------------------------------------------------------------------------
-8.5.3. +deanimate-gifs
+8.5.3. content-type-overwrite
-Type:
+Typical use:
- Parameterized.
+ Stop useless download menus from popping up, or change the browser's
+ rendering mode
-Typical uses:
+Effect:
- To stop those annoying, distracting animated GIF images.
+ Replaces the "Content-Type:" HTTP server header.
-Possible values:
+Type:
- "last" or "first"
+ Parameterized.
-Example usage:
+Parameter:
- {+deanimate-gifs{last}}
- .example.com
-
+ Any string.
Notes:
- De-animate all animated GIF images, i.e. reduce them to their last frame.
- This will also shrink the images considerably (in bytes, not pixels!). If
- the option "first" is given, the first frame of the animation is used as
- the replacement. If "last" is given, the last frame of the animation is
- used instead, which probably makes more sense for most banner animations,
- but also has the risk of not showing the entire last frame (if it is only a
- delta to an earlier frame).
+ The "Content-Type:" HTTP server header is used by the browser to decide
+ what to do with the document. The value of this header can cause the
+ browser to open a download menu instead of displaying the document by
+ itself, even if the document's format is supported by the browser.
+
+ The declared content type can also affect which rendering mode the browser
+ chooses. If XHTML is delivered as "text/html", many browsers treat it as
+ yet another broken HTML document. If it is send as "application/xml",
+ browsers with XHTML support will only display it, if the syntax is correct.
+
+ If you see a web site that proudly uses XHTML buttons, but sets
+ "Content-Type: text/html", you can use Privoxy to overwrite it with
+ "application/xml" and validate the web master's claim inside your
+ XHTML-supporting browser. If the syntax is incorrect, the browser will
+ complain loudly.
+
+ You can also go the opposite direction: if your browser prints error
+ messages instead of rendering a document falsely declared as XHTML, you can
+ overwrite the content type with "text/html" and have it rendered as broken
+ HTML document.
+
+ By default content-type-overwrite only replaces "Content-Type:" headers
+ that look like some kind of text. If you want to overwrite it
+ unconditionally, you have to combine it with force-text-mode. This
+ limitation exists for a reason, think twice before circumventing it.
+
+ Most of the time it's easier to enable filter-server-headers and replace
+ this action with a custom regular expression. It allows you to activate it
+ for every document of a certain site and it will still only replace the
+ content types you aimed at.
+
+ Of course you can apply content-type-overwrite to a whole site and then
+ make URL based exceptions, but it's a lot more work to get the same
+ precision.
+
+Example usage (sections):
+
+ # Check if www.example.net/ really uses valid XHTML
+ {+content-type-overwrite {application/xml}}
+ www.example.net/
+
+ # but leave the content type unmodified if the URL looks like a style sheet
+ {-content-type-overwrite}
+ www.example.net/*.\.css$
+ www.example.net/*.style
-------------------------------------------------------------------------------
-8.5.4. +downgrade-http-version
+8.5.4. crunch-client-header
-Type:
+Typical use:
- Boolean.
+ Remove a client header Privoxy has no dedicated action for.
-Typical uses:
+Effect:
- "+downgrade-http-version" will downgrade HTTP/1.1 client requests to HTTP/
- 1.0 and downgrade the responses as well.
+ Deletes every header sent by the client that contains the string the user
+ supplied as parameter.
-Possible values:
+Type:
- N/A
+ Parameterized.
-Example usage:
+Parameter:
- {+downgrade-http-version}
- .example.com
-
+ Any string.
Notes:
- Use this action for servers that use HTTP/1.1 protocol features that
- Privoxy doesn't handle well yet. HTTP/1.1 is only partially implemented.
- Default is not to downgrade requests. This is an infrequently needed
- action, and is used to help with rare problem sites only.
+ This action allows you to block client headers for which no dedicated
+ Privoxy action exists. Privoxy will remove every client header that
+ contains the string you supplied as parameter.
+
+ Regular expressions are not supported and you can't use this action to
+ block different headers in the same request, unless they contain the same
+ string.
+
+ crunch-client-header is only meant for quick tests. If you have to block
+ several different headers, or only want to modify parts of them, you should
+ enable filter-client-headers and create your own filter.
+
+ +-----------------------------------------------------------------+
+ | Warning |
+ |-----------------------------------------------------------------|
+ |Don't block any header without understanding the consequences. |
+ +-----------------------------------------------------------------+
+Example usage (section):
+
+ # Block the non-existent "Privacy-Violation:" client header
+ {+crunch-client-header {Privacy-Violation:}}
+ /
+
-------------------------------------------------------------------------------
-8.5.5. +fast-redirects
+8.5.5. crunch-if-none-match
+Typical use:
+
+ Prevent yet another way to track the user's steps between sessions.
+
+Effect:
+
+ Deletes the "If-None-Match:" HTTP client header.
+
Type:
Boolean.
-Typical uses:
+Parameter:
- The "+fast-redirects" action enables interception of "redirect" requests
- from one server to another, which are used to track users.Privoxy can cut
- off all but the last valid URL in a redirect request and send a local
- redirect back to your browser without contacting the intermediate site(s).
+ N/A
-Possible values:
+Notes:
- N/A
+ Removing the "If-None-Match:" HTTP client header is useful for filter
+ testing, where you want to force a real reload instead of getting status
+ code "304" which would cause the browser to use a cached copy of the page.
-Example usage:
+ It is also useful to make sure the header isn't used as a cookie
+ replacement.
- {+fast-redirects}
- .example.com
-
+ Blocking the "If-None-Match:" header shouldn't cause any caching problems,
+ as long as the "If-Modified-Since:" header isn't blocked as well.
-Notes:
+ It is recommended to use this action together with hide-if-modified-since
+ and overwrite-last-modified.
- Many sites, like yahoo.com, don't just link to other sites. Instead, they
- will link to some script on their own server, giving the destination as a
- parameter, which will then redirect you to the final target. URLs resulting
- from this scheme typically look like: http://some.place/some_script?http://
- some.where-else.
+Example usage (section):
- Sometimes, there are even multiple consecutive redirects encoded in the
- URL. These redirections via scripts make your web browsing more traceable,
- since the server from which you follow such a link can see where you go to.
- Apart from that, valuable bandwidth and time is wasted, while your browser
- ask the server for one redirect after the other. Plus, it feeds the
- advertisers.
+ # Let the browser revalidate cached documents without being tracked across sessions
+ {+hide-if-modified-since {-60} \
+ +overwrite-last-modified {randomize} \
+ +crunch-if-none-match}
+ /
+
+-------------------------------------------------------------------------------
+
+8.5.6. crunch-incoming-cookies
+
+Typical use:
+
+ Prevent the web server from setting any cookies on your system
+
+Effect:
+
+ Deletes any "Set-Cookie:" HTTP headers from server replies.
- This is a normally "on" feature, and often requires exceptions for sites
- that are sensitive to defeating this mechanism.
+Type:
+
+ Boolean.
+
+Parameter:
+
+ N/A
+
+Notes:
+
+ This action is only concerned with incoming cookies. For outgoing cookies,
+ use crunch-outgoing-cookies. Use both to disable cookies completely.
+
+ It makes no sense at all to use this action in conjunction with the
+ session-cookies-only action, since it would prevent the session cookies
+ from being set. See also filter-content-cookies.
+
+Example usage:
+
+ +crunch-incoming-cookies
-------------------------------------------------------------------------------
-8.5.6. +filter
+8.5.7. crunch-server-header
+Typical use:
+
+ Remove a server header Privoxy has no dedicated action for.
+
+Effect:
+
+ Deletes every header sent by the server that contains the string the user
+ supplied as parameter.
+
Type:
Parameterized.
-Typical uses:
+Parameter:
+
+ Any string.
+
+Notes:
+
+ This action allows you to block server headers for which no dedicated
+ Privoxy action exists. Privoxy will remove every server header that
+ contains the string you supplied as parameter.
+
+ Regular expressions are not supported and you can't use this action to
+ block different headers in the same request, unless they contain the same
+ string.
+
+ crunch-server-header is only meant for quick tests. If you have to block
+ several different headers, or only want to modify parts of them, you should
+ enable filter-server-headers and create your own filter.
+
+ +-----------------------------------------------------------------+
+ | Warning |
+ |-----------------------------------------------------------------|
+ |Don't block any header without understanding the consequences. |
+ +-----------------------------------------------------------------+
+Example usage (section):
+
+ # Crunch server headers that try to prevent caching
+ {+crunch-server-header {no-cache}}
+ /
+
+-------------------------------------------------------------------------------
+
+8.5.8. crunch-outgoing-cookies
+
+Typical use:
+
+ Prevent the web server from reading any cookies from your system
+
+Effect:
+
+ Deletes any "Cookie:" HTTP headers from client requests.
+
+Type:
+
+ Boolean.
+
+Parameter:
+
+ N/A
+
+Notes:
+
+ This action is only concerned with outgoing cookies. For incoming cookies,
+ use crunch-incoming-cookies. Use both to disable cookies completely.
+
+ It makes no sense at all to use this action in conjunction with the
+ session-cookies-only action, since it would prevent the session cookies
+ from being read.
+
+Example usage:
+
+ +crunch-outgoing-cookies
+
+-------------------------------------------------------------------------------
+
+8.5.9. deanimate-gifs
+
+Typical use:
+
+ Stop those annoying, distracting animated GIF images.
+
+Effect:
+
+ De-animate GIF animations, i.e. reduce them to their first or last image.
+
+Type:
+
+ Parameterized.
+
+Parameter:
+
+ "last" or "first"
+
+Notes:
+
+ This will also shrink the images considerably (in bytes, not pixels!). If
+ the option "first" is given, the first frame of the animation is used as
+ the replacement. If "last" is given, the last frame of the animation is
+ used instead, which probably makes more sense for most banner animations,
+ but also has the risk of not showing the entire last frame (if it is only a
+ delta to an earlier frame).
+
+ You can safely use this action with patterns that will also match non-GIF
+ objects, because no attempt will be made at anything that doesn't look like
+ a GIF.
+
+Example usage:
+
+ +deanimate-gifs{last}
+
+-------------------------------------------------------------------------------
+
+8.5.10. downgrade-http-version
+
+Typical use:
+
+ Work around (very rare) problems with HTTP/1.1
+
+Effect:
+
+ Downgrades HTTP/1.1 client requests and server replies to HTTP/1.0.
+
+Type:
+
+ Boolean.
+
+Parameter:
+
+ N/A
+
+Notes:
+
+ This is a left-over from the time when Privoxy didn't support important
+ HTTP/1.1 features well. It is left here for the unlikely case that you
+ experience HTTP/1.1 related problems with some server out there. Not all
+ (optional) HTTP/1.1 features are supported yet, so there is a chance you
+ might need this action.
- Apply page filtering as defined by named sections of the default.filter
- file to the specified site(s). "Filtering" can be any modification of the
- raw page content, including re-writing or deletion of content.
+Example usage (section):
-Possible values:
+ {+downgrade-http-version}
+ problem-host.example.com
- "+filter" must include the name of one of the section identifiers from
- default.filter (or whatever filterfile is specified in config).
+-------------------------------------------------------------------------------
+
+8.5.11. fast-redirects
+
+Typical use:
-Example usage (from the current default.filter):
+ Fool some click-tracking scripts and speed up indirect links.
- +filter{html-annoyances}: Get rid of particularly annoying HTML abuse.
+Effect:
- +filter{js-annoyances}: Get rid of particularly annoying JavaScript abuse
+ Detects redirection URLs and redirects the browser without contacting the
+ redirection server first.
- +filter{content-cookies}: Kill cookies that come in the HTML or JS content
+Type:
- +filter{popups}: Kill all popups in JS and HTML
+ Parameterized.
- +filter{frameset-borders}: Give frames a border and make them resizable
+Parameter:
- +filter{webbugs}: Squish WebBugs (1x1 invisible GIFs used for user
- tracking)
+ + "simple-check" to just search for the string "http://" to detect
+ redirection URLs.
+
+ + "check-decoded-url" to decode URLs (if necessary) before searching for
+ redirection URLs.
+
+Notes:
- +filter{refresh-tags}: Kill automatic refresh tags (for dial-on-demand
- setups)
+ Many sites, like yahoo.com, don't just link to other sites. Instead, they
+ will link to some script on their own servers, giving the destination as a
+ parameter, which will then redirect you to the final target. URLs resulting
+ from this scheme typically look like: "http://www.example.org/
+ click-tracker.cgi?target=http%3a//www.example.net/".
- +filter{fun}: Text replacements for subversive browsing fun!
+ Sometimes, there are even multiple consecutive redirects encoded in the
+ URL. These redirections via scripts make your web browsing more traceable,
+ since the server from which you follow such a link can see where you go to.
+ Apart from that, valuable bandwidth and time is wasted, while your browser
+ asks the server for one redirect after the other. Plus, it feeds the
+ advertisers.
+
+ This feature is currently not very smart and is scheduled for improvement.
+ If it is enabled by default, you will have to create some exceptions to
+ this action. It can lead to failures in several ways:
+
+ Not every URLs with other URLs as parameters is evil. Some sites offer a
+ real service that requires this information to work. For example a
+ validation service needs to know, which document to validate.
+ fast-redirects assumes that every URL parameter that looks like another URL
+ is a redirection target, and will always redirect to the last one. Most of
+ the time the assumption is correct, but if it isn't, the user gets
+ redirected anyway.
+
+ Another failure occurs if the URL contains other parameters after the URL
+ parameter. The URL: "http://www.example.org/?redirect=http%3a//
+ www.example.net/&foo=bar". contains the redirection URL "http://
+ www.example.net/", followed by another parameter. fast-redirects doesn't
+ know that and will cause a redirect to "http://www.example.net/&foo=bar".
+ Depending on the target server configuration, the parameter will be
+ silently ignored or lead to a "page not found" error. It is possible to fix
+ these redirected requests with filter-client-headers but it requires a
+ little effort.
+
+ To detect a redirection URL, fast-redirects only looks for the string
+ "http://", either in plain text (invalid but often used) or encoded as
+ "http%3a//". Some sites use their own URL encoding scheme, encrypt the
+ address of the target server or replace it with a database id. In theses
+ cases fast-redirects is fooled and the request reaches the redirection
+ server where it probably gets logged.
+
+Example usage:
- +filter{nimda}: Remove Nimda (virus) code.
+ { +fast-redirects{simple-check} }
+ .example.com
+
+ { +fast-redirects{check-decoded-url} }
+ another.example.com/testing
- +filter{banners-by-size}: Kill banners by size (very efficient!)
+-------------------------------------------------------------------------------
+
+8.5.12. filter
+
+Typical use:
- +filter{shockwave-flash}: Kill embedded Shockwave Flash objects
+ Get rid of HTML and JavaScript annoyances, banner advertisements (by size),
+ do fun text replacements, etc.
+
+Effect:
+
+ All files of text-based type, most notably HTML and JavaScript, to which
+ this action applies, are filtered on-the-fly through the specified regular
+ expression based substitutions. (Note: as of version 3.0.3 plain text
+ documents are exempted from filtering, because web servers often use the
+ text/plain MIME type for all files whose type they don't know.) By default,
+ filtering works only on the raw document content itself (that which can be
+ seen with View Source), not the headers.
+
+Type:
+
+ Parameterized.
- +filter{crude-parental}: Kill all web pages that contain the words "sex" or
- "warez"
+Parameter:
+
+ The name of a filter, as defined in the filter file. Filters can be defined
+ in one or more files as defined by the filterfile option in the config file
+ . default.filter is the collection of filters supplied by the developers.
+ Locally defined filters should go in their own file, such as user.filter.
+
+ When used in its negative form, and without parameters, all filtering is
+ completely disabled.
Notes:
- This is potentially a very powerful feature! And requires a knowledge of
- regular expressions if you want to "roll your own". Filtering operates on a
- line by line basis throughout the entire page.
+ For your convenience, there are a number of pre-defined filters available
+ in the distribution filter file that you can use. See the examples below
+ for a list.
Filtering requires buffering the page content, which may appear to slow
down page rendering since nothing is displayed until all content has passed
page is not incrementally displayed.) This effect will be more noticeable
on slower connections.
- Filtering can achieve some of the effects as the "+block" action, i.e. it
- can be used to block ads and banners. In the overall scheme of things,
- filtering is one of the first things "Privoxy" does with a web page. So
- other most other actions are applied to the already "filtered" page.
+ "Rolling your own" filters requires a knowledge of "Regular Expressions"
+ and "HTML". This is very powerful feature, and potentially very intrusive.
+ Use with caution.
+
+ The amount of data that can be filtered is limited to the buffer-limit
+ option in the main config file. The default is 4096 KB (4 Megs). Once this
+ limit is exceeded, the buffered data, and all pending data, is passed
+ through unfiltered.
+
+ Inappropriate MIME types, such as zipped files, are not filtered at all.
+ (Again, only text-based types except plain text). Encrypted SSL data (from
+ HTTPS servers) cannot be filtered either, since this would violate the
+ integrity of the secure transaction. In some situations it might be
+ necessary to protect certain text, like source code, from filtering by
+ defining appropriate -filter exceptions.
+
+ At this time, Privoxy cannot uncompress compressed documents. If you want
+ filtering to work on all documents, even those that would normally be sent
+ compressed, use the prevent-compression action in conjunction with filter.
+
+ Filtering can achieve some of the same effects as the block action, i.e. it
+ can be used to block ads and banners. But the mechanism works quite
+ differently. One effective use, is to block ad banners based on their size
+ (see below), since many of these seem to be somewhat standardized.
+
+ Feedback with suggestions for new or improved filters is particularly
+ welcome!
+
+ The below list has only the names and a one-line description of each
+ predefined filter. There are more verbose explanations of what these
+ filters do in the filter file chapter.
+
+Example usage (with filters from the distribution default.filter file). See the
+ Predefined Filters section for more explanation on each:
+
+ +filter{js-annoyances} # Get rid of particularly annoying JavaScript abuse
+
+ +filter{js-events} # Kill all JS event bindings (Radically destructive! Only for extra nasty sites)
+
+ +filter{html-annoyances} # Get rid of particularly annoying HTML abuse
+
+ +filter{content-cookies} # Kill cookies that come in the HTML or JS content
+
+ +filter{refresh-tags} # Kill automatic refresh tags (for dial-on-demand setups)
+
+ +filter{unsolicited-popups} # Disable only unsolicited pop-up windows
+
+ +filter{all-popups} # Kill all popups in JavaScript and HTML
+
+ +filter{img-reorder} # Reorder attributes in <img> tags to make the banners-by-* filters more effective
+
+ +filter{banners-by-size} # Kill banners by size
+
+ +filter{banners-by-link} # Kill banners by their links to known clicktrackers
+
+ +filter{webbugs} # Squish WebBugs (1x1 invisible GIFs used for user tracking)
+
+ +filter{tiny-textforms} # Extend those tiny textareas up to 40x80 and kill the hard wrap
+
+ +filter{jumping-windows} # Prevent windows from resizing and moving themselves
+
+ +filter{frameset-borders} # Give frames a border and make them resizeable
+
+ +filter{demoronizer} # Fix MS's non-standard use of standard charsets
+
+ +filter{shockwave-flash} # Kill embedded Shockwave Flash objects
+
+ +filter{quicktime-kioskmode} # Make Quicktime movies savable
+
+ +filter{fun} # Text replacements for subversive browsing fun!
+
+ +filter{crude-parental} # Crude parental filtering (demo only)
+
+ +filter{ie-exploits} # Disable some known Internet Explorer bug exploits
+
+-------------------------------------------------------------------------------
+
+8.5.13. filter-client-headers
+
+Typical use:
+
+ To apply filtering to the client's (browser's) headers
+
+Effect:
+
+ By default, Privoxy's filters only apply to the document content itself.
+ This will extend those filters to include the client's headers as well.
+
+Type:
+
+ Boolean.
+
+Parameter:
+
+ N/A
+
+Notes:
+
+ Regular expressions can be used to filter headers as well. Check your
+ filters closely before activating this action, as it can easily lead to
+ broken requests.
+
+ These filters are applied to each header on its own, not to them all at
+ once. This makes it easier to diagnose problems, but on the downside you
+ can't write filters that only change header x if header y's value is z.
+
+ The filters are used after the other header actions have finished and can
+ use their output as input.
+
+ Whenever possible one should specify ^, $, the whole header name and the
+ colon, to make sure the filter doesn't cause havoc to other headers or the
+ page itself. For example if you want to transform Galeon User-Agents to
+ Firefox User-Agents you shouldn't use:
+
+ s@Galeon/\d\.\d\.\d @@
+
+ but:
+
+ s@^(User-Agent:.*) Galeon/\d\.\d\.\d (Firefox/\d\.\d\.\d\.\d)$@$1 $2@
+
+Example usage (section):
+
+ {+filter-client-headers +filter{test_filter}}
+ problem-host.example.com
+
+
+-------------------------------------------------------------------------------
+
+8.5.14. filter-server-headers
+
+Typical use:
+
+ To apply filtering to the server's headers
+
+Effect:
+
+ By default, Privoxy's filters only apply to the document content itself.
+ This will extend those filters to include the server's headers as well.
+
+Type:
+
+ Boolean.
+
+Parameter:
+
+ N/A
+
+Notes:
+
+ Similar to filter-client-headers, but works on the server instead. To
+ filter both server and client, use both.
+
+ As with filter-client-headers, check your filters before activating this
+ action, as it can easily lead to broken requests.
+
+ These filters are applied to each header on its own, not to them all at
+ once. This makes it easier to diagnose problems, but on the downside you
+ can't write filters that only change header x if header y's value is z.
+
+ The filters are used after the other header actions have finished and can
+ use their output as input.
+
+ Remember too, whenever possible one should specify ^, $, the whole header
+ name and the colon, to make sure the filter doesn't cause havoc to other
+ headers or the page itself. See above for example.
+
+Example usage (section):
+
+ {+filter-server-headers +filter{test_filter}}
+ problem-host.example.com
+
-------------------------------------------------------------------------------
-8.5.7. +hide-forwarded-for-headers
+8.5.15. force-text-mode
+Typical use:
+
+ Force Privoxy to treat a document as if it was in some kind of text format.
+
+Effect:
+
+ Declares a document as text, even if the "Content-Type:" isn't detected as
+ such.
+
Type:
Boolean.
-Typical uses:
+Parameter:
+
+ N/A
+
+Notes:
+
+ As explained above, Privoxy tries to only filter files that are in some
+ kind of text format. The same restrictions apply to content-type-overwrite.
+ force-text-mode declares a document as text, without looking at the
+ "Content-Type:" first.
- Block any existing X-Forwarded-for HTTP header, and do not add a new one.
+ +-----------------------------------------------------------------+
+ | Warning |
+ |-----------------------------------------------------------------|
+ |Think twice before activating this action. Filtering binary data |
+ |with regular expressions can cause file damage. |
+ +-----------------------------------------------------------------+
+Example usage:
-Possible values:
+ +force-text-mode
+
+
+-------------------------------------------------------------------------------
+
+8.5.16. handle-as-empty-document
+
+Typical use:
+
+ Mark URLs that should be replaced by empty documents if they get blocked
+
+Effect:
+
+ This action alone doesn't do anything noticeable. It just marks URLs. If
+ the block action also applies, the presence or absence of this mark decides
+ whether an HTML "blocked" page, or an empty document will be sent to the
+ client as a substitute for the blocked content. The empty document isn't
+ literally empty, but actually contains a single space.
+
+Type:
+
+ Boolean.
+
+Parameter:
N/A
+Notes:
+
+ Some browsers complain about syntax errors if JavaScript documents are
+ blocked with Privoxy's default HTML page; this option can be used to
+ silence them.
+
+ The content type for the empty document can be specified with
+ content-type-overwrite{}, but usually this isn't necessary.
+
Example usage:
- {+hide-forwarded-for-headers}
- .example.com
-
+ # Block all documents on example.org that end with ".js",
+ # but send an empty document instead of the usual HTML message.
+ {+block +handle-as-empty-document}
+ example.org/.*\.js$
+
+
+-------------------------------------------------------------------------------
+
+8.5.17. handle-as-image
+
+Typical use:
+
+ Mark URLs as belonging to images (so they'll be replaced by images if they
+ do get blocked, rather than HTML pages)
+
+Effect:
+
+ This action alone doesn't do anything noticeable. It just marks URLs as
+ images. If the block action also applies, the presence or absence of this
+ mark decides whether an HTML "blocked" page, or a replacement image (as
+ determined by the set-image-blocker action) will be sent to the client as a
+ substitute for the blocked content.
+
+Type:
+
+ Boolean.
+
+Parameter:
+
+ N/A
Notes:
- It is fairly safe to leave this on. It does not seem to break many sites.
+ The below generic example section is actually part of default.action. It
+ marks all URLs with well-known image file name extensions as images and
+ should be left intact.
+
+ Users will probably only want to use the handle-as-image action in
+ conjunction with block, to block sources of banners, whose URLs don't
+ reflect the file type, like in the second example section.
+
+ Note that you cannot treat HTML pages as images in most cases. For
+ instance, (in-line) ad frames require an HTML page to be sent, or they
+ won't display properly. Forcing handle-as-image in this situation will not
+ replace the ad frame with an image, but lead to error messages.
+
+Example usage (sections):
+
+ # Generic image extensions:
+ #
+ {+handle-as-image}
+ /.*\.(gif|jpg|jpeg|png|bmp|ico)$
+
+ # These don't look like images, but they're banners and should be
+ # blocked as images:
+ #
+ {+block +handle-as-image}
+ some.nasty-banner-server.com/junk.cgi?output=trash
+
+ # Banner source! Who cares if they also have non-image content?
+ ad.doubleclick.net
-------------------------------------------------------------------------------
-8.5.8. +hide-from-header
+8.5.18. hide-accept-language
+Typical use:
+
+ Pretend to use different language settings.
+
+Effect:
+
+ Deletes or replaces the "Accept-Language:" HTTP header in client requests.
+
Type:
Parameterized.
-Typical uses:
+Parameter:
+
+ Keyword: "block", or any user defined value.
+
+Notes:
+
+ Faking the browser's language settings can be useful to make a foreign
+ User-Agent set with hide-user-agent more believable.
+
+ However some sites with content in different languages check the
+ "Accept-Language:" to decide which one to take by default. Sometimes it
+ isn't possible to later switch to another language without changing the
+ "Accept-Language:" header first.
- To block the browser from sending your email address in a "From:" header.
+ Therefore it's a good idea to either only change the "Accept-Language:"
+ header to languages you understand, or to languages that aren't wide
+ spread.
-Possible values:
+ Before setting the "Accept-Language:" header to a rare language, you should
+ consider that it helps to make your requests unique and thus easier to
+ trace. If you don't plan to change this header frequently, you should stick
+ to a common language.
+
+Example usage (section):
+
+ # Pretend to use Canadian language settings.
+ {+hide-accept-language{en-ca} \
+ +hide-user-agent{Mozilla/5.0 (X11; U; OpenBSD i386; en-CA; rv:1.8.0.4) Gecko/20060628 Firefox/1.5.0.4} \
+ }
+ /
+
+-------------------------------------------------------------------------------
+
+8.5.19. hide-content-disposition
+
+Typical use:
+
+ Prevent download menus for content you prefer to view inside the browser.
+
+Effect:
+
+ Deletes or replaces the "Content-Disposition:" HTTP header set by some
+ servers.
+
+Type:
+
+ Parameterized.
+
+Parameter:
Keyword: "block", or any user defined value.
+Notes:
+
+ Some servers set the "Content-Disposition:" HTTP header for documents they
+ assume you want to save locally before viewing them. The
+ "Content-Disposition:" header contains the file name the browser is
+ supposed to use by default.
+
+ In most browsers that understand this header, it makes it impossible to
+ just view the document, without downloading it first, even if it's just a
+ simple text file or an image.
+
+ Removing the "Content-Disposition:" header helps to prevent this annoyance,
+ but some browsers additionally check the "Content-Type:" header, before
+ they decide if they can display a document without saving it first. In
+ these cases, you have to change this header as well, before the browser
+ stops displaying download menus.
+
+ It is also possible to change the server's file name suggestion to another
+ one, but in most cases it isn't worth the time to set it up.
+
Example usage:
- {+hide-from-header{block}}
- .example.com
-
+ # Disarm the download link in Sourceforge's patch tracker
+ {-filter\
+ +content-type-overwrite {text/plain}\
+ +hide-content-disposition {block} }
+ .sourceforge.net/tracker/download.php
+
+-------------------------------------------------------------------------------
+
+8.5.20. hide-if-modified-since
+
+Typical use:
+
+ Prevent yet another way to track the user's steps between sessions.
+
+Effect:
+
+ Deletes the "If-Modified-Since:" HTTP client header or modifies its value.
+
+Type:
+
+ Parameterized.
+
+Parameter:
+
+ Keyword: "block", or a user defined value that specifies a range of hours.
Notes:
- The keyword "block" will completely remove the header (not to be confused
- with the "+block" action). Alternately, you can specify any value you
- prefer to send to the web server.
+ Removing this header is useful for filter testing, where you want to force
+ a real reload instead of getting status code "304", which would cause the
+ browser to use a cached copy of the page.
+
+ Instead of removing the header, hide-if-modified-since can also add or
+ subtract a random amount of time to/from the header's value. You specify a
+ range of minutes where the random factor should be chosen from and Privoxy
+ does the rest. A negative value means subtracting, a positive value adding.
+
+ Randomizing the value of the "If-Modified-Since:" makes sure it isn't used
+ as a cookie replacement, but you will run into caching problems if the
+ random range is too high.
+
+ It is a good idea to only use a small negative value and let
+ overwrite-last-modified handle the greater changes.
+
+ It is also recommended to use this action together with
+ crunch-if-none-match.
+
+Example usage (section):
+
+ # Let the browser revalidate without being tracked across sessions
+ {+hide-if-modified-since {-60}\
+ +overwrite-last-modified {randomize}\
+ +crunch-if-none-match}
+ /
-------------------------------------------------------------------------------
-8.5.9. +hide-referer
+8.5.21. hide-forwarded-for-headers
+Typical use:
+
+ Improve privacy by hiding the true source of the request
+
+Effect:
+
+ Deletes any existing "X-Forwarded-for:" HTTP header from client requests,
+ and prevents adding a new one.
+
Type:
- Parameterized.
+ Boolean.
-Typical uses:
+Parameter:
- Don't send the "Referer:" (sic) HTTP header to the web site. Or,
- alternately send a forged header instead.
+ N/A
+
+Notes:
-Possible values:
+ It is fairly safe to leave this on.
- Prevent the header from being sent with the keyword, "block". Or, "forge" a
- URL to one from the same server as the request. Or, set to user defined
- value of your choice.
+ This action is scheduled for improvement: It should be able to generate
+ forged "X-Forwarded-for:" headers using random IP addresses from a
+ specified network, to make successive requests from the same client look
+ like requests from a pool of different users sharing the same proxy.
Example usage:
- {+hide-referer{forge}}
- .example.com
-
+ +hide-forwarded-for-headers
+
+-------------------------------------------------------------------------------
+
+8.5.22. hide-from-header
+
+Typical use:
+
+ Keep your (old and ill) browser from telling web servers your email address
+
+Effect:
+
+ Deletes any existing "From:" HTTP header, or replaces it with the specified
+ string.
+
+Type:
+
+ Parameterized.
+
+Parameter:
+
+ Keyword: "block", or any user defined value.
Notes:
- "forge" is the preferred option here, since some servers will not send
- images back otherwise.
+ The keyword "block" will completely remove the header (not to be confused
+ with the block action).
+
+ Alternately, you can specify any value you prefer to be sent to the web
+ server. If you do, it is a matter of fairness not to use any address that
+ is actually used by a real person.
- "+hide-referrer" is an alternate spelling of "+hide-referer". It has the
- exact same parameters, and can be freely mixed with, "+hide-referer".
- ("referrer" is the correct English spelling, however the HTTP specification
- has a bug - it requires it to be spelled as "referer".)
+ This action is rarely needed, as modern web browsers don't send "From:"
+ headers anymore.
+
+Example usage:
+
+ +hide-from-header{block}
+
+ or
+
+ +hide-from-header{spam-me-senseless@sittingduck.example.com}
-------------------------------------------------------------------------------
-8.5.10. +hide-user-agent
+8.5.23. hide-referrer
+Typical use:
+
+ Conceal which link you followed to get to a particular site
+
+Effect:
+
+ Deletes the "Referer:" (sic) HTTP header from the client request, or
+ replaces it with a forged one.
+
Type:
Parameterized.
-Typical uses:
+Parameter:
- To change the "User-Agent:" header so web servers can't tell your browser
- type. Who's business is it anyway?
+ + "conditional-block" to delete the header completely if the host has
+ changed.
+
+ + "block" to delete the header unconditionally.
+
+ + "forge" to pretend to be coming from the homepage of the server we are
+ talking to.
+
+ + Any other string to set a user defined referrer.
+
+Notes:
-Possible values:
+ conditional-block is the only parameter, that isn't easily detected in the
+ server's log file. If it blocks the referrer, the request will look like
+ the visitor used a bookmark or typed in the address directly.
- Any user defined string.
+ Leaving the referrer unmodified for requests on the same host allows the
+ server owner to see the visitor's "click path", but in most cases she could
+ also get that information by comparing other parts of the log file: for
+ example the User-Agent if it isn't a very common one, or the user's IP
+ address if it doesn't change between different requests.
+
+ Always blocking the referrer, or using a custom one, can lead to failures
+ on servers that check the referrer before they answer any requests, in an
+ attempt to prevent their valuable content from being embedded or linked to
+ elsewhere.
+
+ Both conditional-block and forge will work with referrer checks, as long as
+ content and valid referring page are on the same host. Most of the time
+ that's the case.
+
+ hide-referer is an alternate spelling of hide-referrer and the two can be
+ can be freely substituted with each other. ("referrer" is the correct
+ English spelling, however the HTTP specification has a bug - it requires it
+ to be spelled as "referer".)
Example usage:
- {+hide-user-agent{Netscape 6.1 (X11; I; Linux 2.4.18 i686)}}
- .msn.com
-
+ +hide-referrer{forge}
+
+ or
+
+ +hide-referrer{http://www.yahoo.com/}
+
+-------------------------------------------------------------------------------
+
+8.5.24. hide-user-agent
+
+Typical use:
+
+ Conceal your type of browser and client operating system
+
+Effect:
+
+ Replaces the value of the "User-Agent:" HTTP header in client requests with
+ the specified value.
+
+Type:
+
+ Parameterized.
+
+Parameter:
+
+ Any user-defined string.
Notes:
- Warning! This breaks many web sites that depend on this in order to
- determine how the target browser will respond to various requests. Use with
- caution.
+ +-----------------------------------------------------------------+
+ | Warning |
+ |-----------------------------------------------------------------|
+ |This can lead to problems on web sites that depend on looking at |
+ |this header in order to customize their content for different |
+ |browsers (which, by the way, is NOT the right thing to do: good |
+ |web sites work browser-independently). |
+ +-----------------------------------------------------------------+
+
+ Using this action in multi-user setups or wherever different types of
+ browsers will access the same Privoxy is not recommended. In single-user,
+ single-browser setups, you might use it to delete your OS version
+ information from the headers, because it is an invitation to exploit known
+ bugs for your OS. It is also occasionally useful to forge this in order to
+ access sites that won't let you in otherwise (though there may be a good
+ reason in some cases). Example of this: some MSN sites will not let Mozilla
+ enter, yet forging to a Netscape 6.1 user-agent works just fine. (Must be
+ just a silly MS goof, I'm sure :-).
+
+ This action is scheduled for improvement.
+
+Example usage:
+
+ +hide-user-agent{Netscape 6.1 (X11; I; Linux 2.4.18 i686)}
-------------------------------------------------------------------------------
-8.5.11. +handle-as-image
+8.5.25. inspect-jpegs
+Typical use:
+
+ To protect against the MS buffer over-run in JPEG processing
+
+Effect:
+
+ Protect against a known exploit
+
Type:
Boolean.
-Typical uses:
+Parameter:
- To define what Privoxy should treat automatically as an image, and is an
- important ingredient of how ads are handled.
+ N/A
-Possible values:
+Notes:
- N/A
+ See Microsoft Security Bulletin MS04-028. JPEG images are one of the most
+ common image types found across the Internet. The exploit as described can
+ allow execution of code on the target system, giving an attacker access to
+ the system in question by merely planting an altered JPEG image, which
+ would have no obvious indications of what lurks inside. This action
+ prevents unwanted intrusion.
Example usage:
- {+handle-as-image}
- /.*\.(gif|jpg|jpeg|png|bmp|ico)
-
+ +inspect-jpegs
+
+-------------------------------------------------------------------------------
+
+8.5.26. kill-popups
+
+Typical use:
+
+ Eliminate those annoying pop-up windows (deprecated)
+
+Effect:
+
+ While loading the document, replace JavaScript code that opens pop-up
+ windows with (syntactically neutral) dummy code on the fly.
+
+Type:
+
+ Boolean.
+
+Parameter:
+
+ N/A
Notes:
- This only has meaning if the URL (or pattern) also is "+block"ed, in which
- case a user definable image can be sent rather than a HTML page. This is
- integral to the whole concept of ad blocking: the URL must match both a
- "+block" rule, and "+handle-as-image". (See "+set-image-blocker" below for
- control over what will actually be displayed by the browser.)
+ This action is basically a built-in, hardwired special-purpose filter
+ action, but there are important differences: For kill-popups, the document
+ need not be buffered, so it can be incrementally rendered while
+ downloading. But kill-popups doesn't catch as many pop-ups as filter
+ {all-popups} does and is not as smart as filter{unsolicited-popups} is.
+
+ Think of it as a fast and efficient replacement for a filter that you can
+ use if you don't want any filtering at all. Note that it doesn't make sense
+ to combine it with any filter action, since as soon as one filter applies,
+ the whole document needs to be buffered anyway, which destroys the
+ advantage of the kill-popups action over its filter equivalent.
+
+ Killing all pop-ups unconditionally is problematic. Many shops and banks
+ rely on pop-ups to display forms, shopping carts etc, and the filter
+ {unsolicited-popups} does a fairly good job of catching only the unwanted
+ ones.
+
+ If the only kind of pop-ups that you want to kill are exit consoles (those
+ really nasty windows that appear when you close an other one), you might
+ want to use filter{js-annoyances} instead.
+
+Example usage:
- There is little reason to change the default definition for this action.
+ +kill-popups
-------------------------------------------------------------------------------
-8.5.12. +set-image-blocker
+8.5.27. limit-connect
+Typical use:
+
+ Prevent abuse of Privoxy as a TCP proxy relay or disable SSL for untrusted
+ sites
+
+Effect:
+
+ Specifies to which ports HTTP CONNECT requests are allowable.
+
Type:
Parameterized.
-Typical uses:
+Parameter:
+
+ A comma-separated list of ports or port ranges (the latter using dashes,
+ with the minimum defaulting to 0 and the maximum to 65K).
+
+Notes:
+
+ By default, i.e. if no limit-connect action applies, Privoxy only allows
+ HTTP CONNECT requests to port 443 (the standard, secure HTTPS port). Use
+ limit-connect if more fine-grained control is desired for some or all
+ destinations.
+
+ The CONNECT methods exists in HTTP to allow access to secure websites
+ ("https://" URLs) through proxies. It works very simply: the proxy connects
+ to the server on the specified port, and then short-circuits its
+ connections to the client and to the remote server. This can be a big
+ security hole, since CONNECT-enabled proxies can be abused as TCP relays
+ very easily.
+
+ Privoxy relays HTTPS traffic without seeing the decoded content. Websites
+ can leverage this limitation to circumvent Privoxy's filters. By specifying
+ an invalid port range you can disable HTTPS entirely. If you plan to
+ disable SSL by default, consider enabling
+ treat-forbidden-connects-like-blocks as well, to be able to quickly create
+ exceptions.
+
+Example usages:
- Decide what to do with URLs that end up tagged with both "+block" and
- "+handle-as-image", e.g an advertisement.
+ +limit-connect{443} # This is the default and need not be specified.
+ +limit-connect{80,443} # Ports 80 and 443 are OK.
+ +limit-connect{-3, 7, 20-100, 500-} # Ports less than 3, 7, 20 to 100 and above 500 are OK.
+ +limit-connect{-} # All ports are OK
+ +limit-connect{,} # No HTTPS/SSL traffic is allowed
-Possible values:
+-------------------------------------------------------------------------------
+
+8.5.28. prevent-compression
+
+Typical use:
- There are four available options: "-set-image-blocker" will send a HTML
- "blocked" page, usually resulting in a "broken image" icon.
- "+set-image-blocker{blank}" will send a 1x1 transparent GIF image.
- "+set-image-blocker{pattern}" will send a checkerboard type pattern (the
- default). And finally, "+set-image-blocker{http://xyz.com}" will send a
- HTTP temporary redirect to the specified image. This has the advantage of
- the icon being being cached by the browser, which will speed up the
- display.
+ Ensure that servers send the content uncompressed, so it can be passed
+ through filters.
+
+Effect:
+
+ Removes the Accept-Encoding header which can be used to ask for compressed
+ transfer.
+
+Type:
+
+ Boolean.
-Example usage:
+Parameter:
- {+set-image-blocker{blank}}
- .example.com
-
+ N/A
Notes:
- If you want invisible ads, they need to meet criteria as matching both
- images and blocked actions. And then, "image-blocker" should be set to
- "blank" for invisibility. Note you cannot treat HTML pages as images in
- most cases. For instance, frames require an HTML page to display. So a
- frame that is an ad, typically cannot be treated as an image. Forcing an
- "image" in this situation just will not work reliably.
+ More and more websites send their content compressed by default, which is
+ generally a good idea and saves bandwidth. But for the filter,
+ deanimate-gifs and kill-popups actions to work, Privoxy needs access to the
+ uncompressed data. Unfortunately, Privoxy can't yet(!) uncompress, filter,
+ and re-compress the content on the fly. So if you want to ensure that all
+ websites, including those that normally compress, can be filtered, you need
+ to use this action.
+
+ This will slow down transfers from those websites, though. If you use any
+ of the above-mentioned actions, you will typically want to use
+ prevent-compression in conjunction with them.
+
+ Note that some (rare) ill-configured sites don't handle requests for
+ uncompressed documents correctly (they send an empty document body). If you
+ use prevent-compression per default, you'll have to add exceptions for
+ those sites. See the example for how to do that.
+
+Example usage (sections):
+
+ # Set default:
+ #
+ {+prevent-compression}
+ / # Match all sites
+
+ # Make exceptions for ill sites:
+ #
+ {-prevent-compression}
+ www.debianhelp.org
+ www.pclinuxonline.com
-------------------------------------------------------------------------------
-8.5.13. +limit-connect
+8.5.29. overwrite-last-modified
+Typical use:
+
+ Prevent yet another way to track the user's steps between sessions.
+
+Effect:
+
+ Deletes the "Last-Modified:" HTTP server header or modifies its value.
+
Type:
Parameterized.
-Typical uses:
+Parameter:
- By default, Privoxy only allows HTTP CONNECT requests to port 443 (the
- standard, secure HTTPS port). Use "+limit-connect" to disable this
- altogether, or to allow more ports.
+ One of the keywords: "block", "reset-to-request-time" and "randomize"
-Possible values:
+Notes:
- Any valid port number, or port number range.
+ Removing the "Last-Modified:" header is useful for filter testing, where
+ you want to force a real reload instead of getting status code "304", which
+ would cause the browser to reuse the old version of the page.
-Example usages:
+ The "randomize" option overwrites the value of the "Last-Modified:" header
+ with a randomly chosen time between the original value and the current
+ time. In theory the server could send each document with a different
+ "Last-Modified:" header to track visits without using cookies. "Randomize"
+ makes it impossible and the browser can still revalidate cached documents.
- +limit-connect{443} #
- This is the default and need not be specified.
- +limit-connect{80,443} # Ports 80 and 443 are OK.
- +limit-connect{-3, 7, 20-100, 500-} #
- Port less than 3, 7, 20 to 100 and above 500 are OK.
-
+ "reset-to-request-time" overwrites the value of the "Last-Modified:" header
+ with the current time. You could use this option together with
+ hided-if-modified-since to further customize your random range.
-Notes:
+ The preferred parameter here is "randomize". It is safe to use, as long as
+ the time settings are more or less correct. If the server sets the
+ "Last-Modified:" header to the time of the request, the random range
+ becomes zero and the value stays the same. Therefore you should later
+ randomize it a second time with hided-if-modified-since, just to be sure.
- The CONNECT methods exists in HTTP to allow access to secure websites
- (https:// URLs) through proxies. It works very simply: the proxy connects
- to the server on the specified port, and then short-circuits its
- connections to the client and to the remote proxy. This can be a big
- security hole, since CONNECT-enabled proxies can be abused as TCP relays
- very easily.
+ It is also recommended to use this action together with
+ crunch-if-none-match.
- If you want to allow CONNECT for more ports than this, or want to forbid
- CONNECT altogether, you can specify a comma separated list of ports and
- port ranges (the latter using dashes, with the minimum defaulting to 0 and
- max to 65K).
+Example usage:
- If you don't know what any of this means, there probably is no reason to
- change this one.
+ # Let the browser revalidate without being tracked across sessions
+ {+hide-if-modified-since {-60}\
+ +overwrite-last-modified {randomize}\
+ +crunch-if-none-match}
+ /
-------------------------------------------------------------------------------
-8.5.14. +prevent-compression
+8.5.30. redirect
-Type:
+Typical use:
- Boolean.
+ Redirect requests to other sites.
-Typical uses:
+Effect:
- Prevent the specified websites from compressing HTTP data.
+ Convinces the browser that the requested document has been moved to another
+ location and the browser should get it from there.
-Possible values:
+Type:
- N/A
+ Parameterized
-Example usage:
+Parameter:
- {+prevent-compression}
- .example.com
-
+ Any URL.
Notes:
- Some websites do this, which can be a problem for Privoxy, since "+filter",
- "+kill-popups" and "+gif-deanimate" will not work on compressed data. This
- will slow down connections to those websites, though. Default typically is
- to turn "prevent-compression" on.
+ This action is useful to replace whole documents with ones of your
+ choosing. This can be used to enforce safe surfing, or just as a simple
+ convenience.
+
+ You can do the same by combining the actions block, handle-as-image and
+ set-image-blocker{URL}. It doesn't sound right for non-image documents, and
+ that's why this action was created.
+
+ This action will be ignored if you use it together with block.
+
+Example usages:
+
+ # Replace example.com's style sheet with another one
+ { +redirect{http://localhost/css-replacements/example.com.css} }
+ example.com/stylesheet.css
+
+ # Create a short, easy to remember nickname for a favorite site
+ { +redirect{http://www.privoxy.org/user-manual/actions-file.html} }
+ a
-------------------------------------------------------------------------------
-8.5.15. +session-cookies-only
+8.5.31. send-vanilla-wafer
-Type:
+Typical use:
- Boolean.
+ Feed log analysis scripts with useless data.
-Typical uses:
+Effect:
- Allow cookies for the current browser session only.
+ Sends a cookie with each request stating that you do not accept any
+ copyright on cookies sent to you, and asking the site operator not to track
+ you.
-Possible values:
+Type:
- N/A
+ Boolean.
-Example usage (disabling):
+Parameter:
- {-session-cookies-only}
- .example.com
-
+ N/A
Notes:
- If websites set cookies, "+session-cookies-only" will make sure they are
- erased when you exit and restart your web browser. This makes profiling
- cookies useless, but won't break sites which require cookies so that you
- can log in for transactions. This is generally turned on for all sites, and
- is the recommended setting.
+ The vanilla wafer is a (relatively) unique header and could conceivably be
+ used to track you.
+
+ This action is rarely used and not enabled in the default configuration.
+
+Example usage:
- "+prevent-*-cookies" actions should be turned off as well (see below), for
- "+session-cookies-only" to work. Or, else no cookies will get through at
- all. For, "persistent" cookies that survive across browser sessions, see
- below as well.
+ +send-vanilla-wafer
-------------------------------------------------------------------------------
-8.5.16. +prevent-reading-cookies
+8.5.32. send-wafer
-Type:
+Typical use:
- Boolean.
+ Send custom cookies or feed log analysis scripts with even more useless
+ data.
-Typical uses:
+Effect:
- Explicitly prevent the web server from reading any cookies on your system.
+ Sends a custom, user-defined cookie with each request.
-Possible values:
+Type:
- N/A
+ Multi-value.
-Example usage:
+Parameter:
- {+prevent-reading-cookies}
- .example.com
-
+ A string of the form "name=value".
Notes:
- Often used in conjunction with "+prevent-setting-cookies" to disable
- cookies completely. Note that "+session-cookies-only" requires these to
- both be disabled (or else it never gets any cookies to cache).
+ Being multi-valued, multiple instances of this action can apply to the same
+ request, resulting in multiple cookies being sent.
- For "persistent" cookies to work (i.e. they survive across browser sessions
- and reboots), all three cookie settings should be "off" for the specified
- sites.
+ This action is rarely used and not enabled in the default configuration.
+
+Example usage (section):
+
+ {+send-wafer{UsingPrivoxy=true}}
+ my-internal-testing-server.void
-------------------------------------------------------------------------------
-8.5.17. +prevent-setting-cookies
+8.5.33. session-cookies-only
-Type:
+Typical use:
- Boolean.
+ Allow only temporary "session" cookies (for the current browser session
+ only).
-Typical uses:
+Effect:
- Explicitly block the web server from storing cookies on your system.
+ Deletes the "expires" field from "Set-Cookie:" server headers. Most
+ browsers will not store such cookies permanently and forget them in between
+ sessions.
-Possible values:
+Type:
- N/A
+ Boolean.
-Example usage:
+Parameter:
- {+prevent-setting-cookies}
- .example.com
-
+ N/A
Notes:
- Often used in conjunction with "+prevent-reading-cookies" to disable
- cookies completely (see above).
-
--------------------------------------------------------------------------------
-
-8.5.18. +kill-popups
-
-Type:
+ This is less strict than crunch-incoming-cookies / crunch-outgoing-cookies
+ and allows you to browse websites that insist or rely on setting cookies,
+ without compromising your privacy too badly.
- Boolean.
+ Most browsers will not permanently store cookies that have been processed
+ by session-cookies-only and will forget about them between sessions. This
+ makes profiling cookies useless, but won't break sites which require
+ cookies so that you can log in for transactions. This is generally turned
+ on for all sites, and is the recommended setting.
-Typical uses:
+ It makes no sense at all to use session-cookies-only together with
+ crunch-incoming-cookies or crunch-outgoing-cookies. If you do, cookies will
+ be plainly killed.
- Stop those annoying JavaScript pop-up windows!
+ Note that it is up to the browser how it handles such cookies without an
+ "expires" field. If you use an exotic browser, you might want to try it out
+ to be sure.
-Possible values:
+ This setting also has no effect on cookies that may have been stored
+ previously by the browser before starting Privoxy. These would have to be
+ removed manually.
- N/A
+ Privoxy also uses the content-cookies filter to block some types of
+ cookies. Content cookies are not effected by session-cookies-only.
Example usage:
- {+kill-popups}
- .example.com
-
-
-Notes:
-
- "+kill-popups" uses a built in filter to disable pop-ups that use the
- window.open() function, etc. This is one of the first actions processed by
- Privoxy as it contacts the remote web server. This action is not always
- 100% reliable, and is supplemented by "+filter{popups}".
+ +session-cookies-only
-------------------------------------------------------------------------------
-8.5.19. +send-vanilla-wafer
+8.5.34. set-image-blocker
+Typical use:
+
+ Choose the replacement for blocked images
+
+Effect:
+
+ This action alone doesn't do anything noticeable. If both block and
+ handle-as-image also apply, i.e. if the request is to be blocked as an
+ image, then the parameter of this action decides what will be sent as a
+ replacement.
+
Type:
- Boolean.
+ Parameterized.
-Typical uses:
+Parameter:
- Sends a cookie for every site stating that you do not accept any copyright
- on cookies sent to you, and asking them not to track you.
+ + "pattern" to send a built-in checkerboard pattern image. The image is
+ visually decent, scales very well, and makes it obvious where banners
+ were busted.
+
+ + "blank" to send a built-in transparent image. This makes banners
+ disappear completely, but makes it hard to detect where Privoxy has
+ blocked images on a given page and complicates troubleshooting if
+ Privoxy has blocked innocent images, like navigation icons.
+
+ + "target-url" to send a redirect to target-url. You can redirect to any
+ image anywhere, even in your local filesystem via "file:///" URL. (But
+ note that not all browsers support redirecting to a local file system).
+
+ A good application of redirects is to use special Privoxy-built-in
+ URLs, which send the built-in images, as target-url. This has the same
+ visual effect as specifying "blank" or "pattern" in the first place,
+ but enables your browser to cache the replacement image, instead of
+ requesting it over and over again.
+
+Notes:
-Possible values:
+ The URLs for the built-in images are "http://config.privoxy.org/
+ send-banner?type=type", where type is either "blank" or "pattern".
- N/A
+ There is a third (advanced) type, called "auto". It is NOT to be used in
+ set-image-blocker, but meant for use from filters. Auto will select the
+ type of image that would have applied to the referring page, had it been an
+ image.
Example usage:
- {+send-vanilla-wafer}
- .example.com
-
+ Built-in pattern:
-Notes:
+ +set-image-blocker{pattern}
- This action only applies if you are using a jarfile for saving cookies. Of
- course, this is a (relatively) unique header and could conceivably be used
- to track you.
+ Redirect to the BSD devil:
+
+ +set-image-blocker{http://www.freebsd.org/gifs/dae_up3.gif}
+
+ Redirect to the built-in pattern for better caching:
+
+ +set-image-blocker{http://config.privoxy.org/send-banner?type=pattern}
-------------------------------------------------------------------------------
-8.5.20. +send-wafer
+8.5.35. treat-forbidden-connects-like-blocks
-Type:
+Typical use:
- Multi-value.
+ Block forbidden connects with an easy to find error message.
-Typical uses:
+Effect:
- This allows you to send an arbitrary, user definable cookie.
+ If this action is enabled, Privoxy no longer makes a difference between
+ forbidden connects and ordinary blocks.
-Possible values:
+Type:
- User specified cookie name and corresponding value.
+ Boolean
-Example usage:
+Parameter:
- {+send-wafer{name=value}}
- .example.com
-
+ N/A
Notes:
- This can be specified multiple times in order to add as many cookies as you
- like.
+ By default Privoxy answers forbidden "Connect" requests with a short error
+ message inside the headers. If the browser doesn't display headers (most
+ don't), you just see an empty page.
+
+ With this action enabled, Privoxy displays the message that is used for
+ ordinary blocks instead. If you decide to make an exception for the page in
+ question, you can do so by following the "See why" link.
+
+ For "Connect" requests the clients tell Privoxy which host they are
+ interested in, but not which document they plan to get later. As a result,
+ the "Go there anyway" link becomes rather useless: it lets the client
+ request the home page of the forbidden host through unencrypted HTTP, still
+ using the port of the last request.
+
+ If you previously configured Privoxy to do the request through a SSL
+ tunnel, everything will work. Most likely you haven't and the server will
+ respond with an error message because it is expecting HTTPS (SSL).
+
+Example usage:
+
+ +treat-forbidden-connects-like-blocks
-------------------------------------------------------------------------------
-8.5.21. Summary
+8.5.36. Summary
Note that many of these actions have the potential to cause a page to
misbehave, possibly even not to display at all. There are many ways a site
-------------------------------------------------------------------------------
-8.5.22. Sample Actions Files
-
-Remember that the meaning of any of the above references is reversed by
-preceding the action with a "-", in place of the "+". Also, that some actions
-are turned on in the default section of the actions file, and require little to
-no additional configuration. These are just "on".
-
-But, other actions that are turned on in the default section do typically
-require exceptions to be listed in the latter sections of one of our actions
-file. For instance, by default no URLs are "blocked" (i.e. in the default
-definitions of default.action). We need exceptions to this in order to enable
-ad blocking in the lower sections. But we need to be very selective about what
-we do block. Thus, the default is "off" for blocking.
-
-Below is a liberally commented sample default.action file to demonstrate how
-all the pieces come together. And to show how exceptions to the default
-policies can be handled. This is followed by a brief user.action with similar
-examples.
-
-# Sample default.action file <developers@privoxy.org>
-
-# Settings -- Don't change! For internal Privoxy use ONLY.
-{{settings}}
-for-privoxy-version=3.0
-
-
-##########################################################################
-# Aliases must be defined *before* they are used. These are
-# easier to remember, and can combine several actions into one. Once
-# defined they can be used just like any built-in action -- but within
-# this file only! Aliases do not require a + or - sign.
-##########################################################################
-
-# Some useful aliases.
-# Alias to turn off cookie handling, ie allow all cookies unmolested.
- -prevent-cookies = -prevent-setting-cookies -prevent-reading-cookies \
- -session-cookies-only
-
-# Alias to both block and treat as if an image for ad blocking
-# purposes.
- +imageblock = +block +handle-as-image
-
-# Fragile sites should have the minimum changes:
- fragile = -block -deanimate-gifs -fast-redirects -filter -hide-referer \
- -prevent-cookies -kill-popups
-
-# Shops should be allowed to set persistent cookies
- shop = -filter -prevent-cookies -session-cookies-only
-
-
-##########################################################################
-# Begin default action settings. Anything in this section will match
-# all URLs -- UNLESS we have exceptions that also match, defined below this
-# section. We will show all potential actions here whether they are on
-# or off. We could omit any disabled action if we wanted, since all
-# actions are 'off' by default anyway. Shown for completeness only.
-# Actions are enabled if preceded by a '+', otherwise they are disabled
-# (unless an alias has been defined without this).
-##########################################################################
- { \
- -add-header \
- -block \
- -deanimate-gifs \
- -downgrade-http-version \
- +fast-redirects \
- +filter{html-annoyances} \
- +filter{js-annoyances} \
- -filter{content-cookies} \
- -filter{popups} \
- +filter{webbugs} \
- -filter{refresh-tags} \
- -filter{fun} \
- +filter{nimda} \
- +filter{banners-by-size} \
- -filter{shockwave-flash} \
- -filter{crude-prental} \
- +hide-forwarded-for-headers \
- +hide-from-header{block} \
- -hide-referrer \
- -hide-user-agent \
- -handle-as-image \
- +set-image-blocker{pattern} \
- -limit-connect \
- +prevent-compression \
- -session-cookies-only \
- -prevent-reading-cookies \
- -prevent-setting-cookies \
- -kill-popups \
- -send-vanilla-wafer \
- -send-wafer \
- }
- / # forward slash will match *all* potential URL patterns.
-
-##########################################################################
-# Default behavior is now set. Now we will define some exceptions to our
-# default action policies.
-##########################################################################
-
-# These sites are very complex and require very minimal interference.
-# We'll disable most actions with our 'fragile' alias:
- { fragile }
- .office.microsoft.com # surprise, surprise!
- .windowsupdate.microsoft.com
-
-
-# Shopping sites - not as fragile but require some special
-# handling. We still want to block ads, and we will allow
-# persistant cookies via the 'shop' alias:
- { shop }
- .quietpc.com
- .worldpay.com # for quietpc.com
- .jungle.com
- .scan.co.uk
-
-
-# These sites require pop-ups too :( We'll combine our 'shop'
-# alias with two other actions into one rule to allow all popups.
- { shop -kill-popups -filter{popups} }
- .dabs.com
- .overclockers.co.uk
-
-
-# The 'Fast-redirects' action breaks some sites. Disable this action
-# for these known sensitive sites:
- { -fast-redirects }
- login.yahoo.com
- edit.europe.yahoo.com
- .google.com
- .altavista.com/.*(like|url|link):http
- .altavista.com/trans.*urltext=http
- .nytimes.com
-
-
-# Define which file types will be treated as images. Important
-# for ad blocking.
- { +handle-as-image }
- /.*\.(gif|jpe?g|png|bmp|ico)
-
-
-# Now lets list some domains that are known ad generators. And
-# our alias that we use here will block these as well as force
-# them to be treated as images. This combination of actions is
-# important for ad blocking. What the browser will show instead is
-# determined by the setting of "+set-image-blocker"
- { +imageblock }
- ar.atwola.com
- .ad.doubleclick.net
- .a.yimg.com/(?:(?!/i/).)*$
- .a[0-9].yimg.com/(?:(?!/i/).)*$
- bs*.gsanet.com
- bs*.einets.com
- .qkimg.net
- ad.*.doubleclick.net
-
-
-# These will just simply be blocked. They will generate the BLOCKED
-# banner page, if matched. Heavy use of wildcards and regular
-# expressions in this example. Enable block action:
- { +block }
- ad*.
- .*ads.
- banner?.
- count*.
- /.*count(er)?\.(pl|cgi|exe|dll|asp|php[34]?)
- /(?:.*/)?(publicite|werbung|rekla(ma|me|am)|annonse|maino(kset|nta|s)?)/
- .hitbox.com
-
-
-# The above block section will probably inadvertantly catch some
-# sites we DO NOT want blocked via the wildcards and regular expressions.
-# Now let's set exceptions to the exceptions so the good guys get better
-# treatment. Disable block action:
- { -block }
- advogato.org
- adsl.
- ad[ud]*.
- advice.
-# Let's just trust all .edu top level domains.
- .edu
- www.ugu.com/sui/ugu/adv
-# We'll need to access to path names containing 'download'
- .*downloads.
- /downloads/
-# 'adv' is for globalintersec and means advanced, not advertisement
- www.globalintersec.com/adv
-
-
-# Don't filter *anything* from our friends at sourceforge.
-# Notice we don't have to name the individual filter
-# identifiers -- we just turn them all off in one fell swoop.
-# Disable all filters for this one site:
- { -filter }
- .sourceforge.net
-
-
-So far we are painting with a broad brush by setting general policies. The
-above would be a reasonable starting point for many situations. Now, we want to
-be more specific and have customized rules that are more suitable to our
-personal habits and preferences. These would be for narrowly defined situations
-like your ISP or your bank, and should be placed in user.action, which is
-parsed after all other actions files and should not be clobbered by upgrades.
-So any settings here, will have the last word and over-ride any previously
-defined actions.
-
-Now a few examples of some things that one might do with a user.action file.
-
-# Sample user.action file.
-
-# Any aliases you want to use need to be re-defined here.
-# Alias to turn off cookie handling, ie allow all cookies unmolested.
- -prevent-cookies = -prevent-setting-cookies -prevent-reading-cookies \
- -session-cookies-only
-
-# Fragile sites should have the minimum changes:
- fragile = -block -deanimate-gifs -fast-redirects -filter -hide-referer \
- -prevent-cookies -kill-popups
-
-# Allow persistent cookies for a few regular sites that we
-# trust via our above alias. These will be saved from one browser session
-# to the next. We are explicity turning off any and all cookie handling,
-# even though the prevent-*-cookie settings were disabled in our above
-# default.action anyway. So cookies from these domains will come through
-# unmolested.
- { -prevent-cookies }
- .sun.com
- .yahoo.com
- .msdn.microsoft.com
- .redhat.com
-
-
-# My ISP uses obnoxious self promoting images on many pages.
-# Nuke them :) Note that "+handle-as-image" need not be specified,
-# since all URLs ending in .gif will be tagged as images by the
-# general rules in default.action anyway.
- { +block }
- www.my-isp-example.com/logo[0-9].gif
-
-
-# Say the site where you do your homebanking needs to open
-# popup windows, but you have chosen to kill popups by
-# default. This will allow it for your-example-bank.com:
-#
- { -filter{popups} -kill-popups }
- .my-example-bank.com
-
-
-# This site is delicate, and requires kid-glove
-# treatment.
- { fragile }
- .forbes.com
-
+8.6. Aliases
+
+Custom "actions", known to Privoxy as "aliases", can be defined by combining
+other actions. These can in turn be invoked just like the built-in actions.
+Currently, an alias name can contain any character except space, tab, "=", "{"
+and "}", but we strongly recommend that you only use "a" to "z", "0" to "9",
+"+", and "-". Alias names are not case sensitive, and are not required to start
+with a "+" or "-" sign, since they are merely textually expanded.
+
+Aliases can be used throughout the actions file, but they must be defined in a
+special section at the top of the file! And there can only be one such section
+per actions file. Each actions file may have its own alias section, and the
+aliases defined in it are only visible within that file.
+
+There are two main reasons to use aliases: One is to save typing for frequently
+used combinations of actions, the other one is a gain in flexibility: If you
+decide once how you want to handle shops by defining an alias called "shop",
+you can later change your policy on shops in one place, and your changes will
+take effect everywhere in the actions file where the "shop" alias is used.
+Calling aliases by their purpose also makes your actions files more readable.
+
+Currently, there is one big drawback to using aliases, though: Privoxy's
+built-in web-based action file editor honors aliases when reading the actions
+files, but it expands them before writing. So the effects of your aliases are
+of course preserved, but the aliases themselves are lost when you edit sections
+that use aliases with it. This is likely to change in future versions of
+Privoxy.
+
+Now let's define some aliases...
+
+ # Useful custom aliases we can use later.
+ #
+ # Note the (required!) section header line and that this section
+ # must be at the top of the actions file!
+ #
+ {{alias}}
+
+ # These aliases just save typing later:
+ # (Note that some already use other aliases!)
+ #
+ +crunch-all-cookies = +crunch-incoming-cookies +crunch-outgoing-cookies
+ -crunch-all-cookies = -crunch-incoming-cookies -crunch-outgoing-cookies
+ +block-as-image = +block +handle-as-image
+ mercy-for-cookies = -crunch-all-cookies -session-cookies-only -filter{content-cookies}
+
+ # These aliases define combinations of actions
+ # that are useful for certain types of sites:
+ #
+ fragile = -block -filter -crunch-all-cookies -fast-redirects -hide-referrer -kill-popups
+ shop = -crunch-all-cookies -filter{all-popups} -kill-popups
+
+ # Short names for other aliases, for really lazy people ;-)
+ #
+ c0 = +crunch-all-cookies
+ c1 = -crunch-all-cookies
+
+...and put them to use. These sections would appear in the lower part of an
+actions file and define exceptions to the default actions (as specified further
+up for the "/" pattern):
+
+ # These sites are either very complex or very keen on
+ # user data and require minimal interference to work:
+ #
+ {fragile}
+ .office.microsoft.com
+ .windowsupdate.microsoft.com
+ .nytimes.com
+
+ # Shopping sites:
+ # Allow cookies (for setting and retrieving your customer data)
+ #
+ {shop}
+ .quietpc.com
+ .worldpay.com # for quietpc.com
+ .scan.co.uk
+
+ # These shops require pop-ups:
+ #
+ {shop -kill-popups -filter{all-popups}}
+ .dabs.com
+ .overclockers.co.uk
+
+Aliases like "shop" and "fragile" are often used for "problem" sites that
+require some actions to be disabled in order to function properly.
-------------------------------------------------------------------------------
-8.6. Aliases
+8.7. Actions Files Tutorial
-Custom "actions", known to Privoxy as "aliases", can be defined by combining
-other "actions". These can in turn be invoked just like the built-in "actions".
-Currently, an alias can contain any character except space, tab, "=", "{" or "}
-". But please use only "a"- "z", "0"-"9", "+", and "-". Alias names are not
-case sensitive, and must be defined before other actions in the actions file!
-And there can only be one set of "aliases" defined per file. Each actions file
-may have its own aliases, but they are only visible within that file. Aliases
-do not requir a "+" or "-" sign in front, since they are merely expanded.
+The above chapters have shown which actions files there are and how they are
+organized, how actions are specified and applied to URLs, how patterns work,
+and how to define and use aliases. Now, let's look at an example default.action
+and user.action file and see how all these pieces come together:
-Now let's define a few aliases:
+-------------------------------------------------------------------------------
- # Useful custom aliases we can use later. These must come first!
- {{alias}}
- +prevent-cookies = +prevent-setting-cookies +prevent-reading-cookies
- -prevent-cookies = -prevent-setting-cookies -prevent-reading-cookies
- fragile =
- -block -prevent-cookies -filter -fast-redirects -hide-referer -kill-popups
- shop = -prevent-cookies -filter -fast-redirects
- +imageblock = +block +handle-as-image
+8.7.1. default.action
- # Aliases defined from other aliases, for people who don't like to type
- # too much: ;-)
- c0 = +prevent-cookies
- c1 = -prevent-cookies
- #... etc. Customize to your heart's content.
-
+Every config file should start with a short comment stating its purpose:
-Some examples using our "shop" and "fragile" aliases from above. These would
-appear in the lower sections of an actions file as exceptions to the default
-actions (as defined in the upper section):
+# Sample default.action file <ijbswa-developers@lists.sourceforge.net>
- # These sites are very complex and require
- # minimal interference.
- {fragile}
- .office.microsoft.com
- .windowsupdate.microsoft.com
- .nytimes.com
+Then, since this is the default.action file, the first section is a special
+section for internal use that you needn't change or worry about:
- # Shopping sites - but we still want to block ads.
- {shop}
- .quietpc.com
- .worldpay.com # for quietpc.com
- .scan.co.uk
+##########################################################################
+# Settings -- Don't change! For internal Privoxy use ONLY.
+##########################################################################
+
+{{settings}}
+for-privoxy-version=3.0
+
+After that comes the (optional) alias section. We'll use the example section
+from the above chapter on aliases, that also explains why and how aliases are
+used:
+
+##########################################################################
+# Aliases
+##########################################################################
+{{alias}}
+
+ # These aliases just save typing later:
+ # (Note that some already use other aliases!)
+ #
+ +crunch-all-cookies = +crunch-incoming-cookies +crunch-outgoing-cookies
+ -crunch-all-cookies = -crunch-incoming-cookies -crunch-outgoing-cookies
+ +block-as-image = +block +handle-as-image
+ mercy-for-cookies = -crunch-all-cookies -session-cookies-only -filter{content-cookies}
+
+ # These aliases define combinations of actions
+ # that are useful for certain types of sites:
+ #
+ fragile = -block -filter -crunch-all-cookies -fast-redirects -hide-referrer -kill-popups
+ shop = -crunch-all-cookies -filter{all-popups} -kill-popups
+
+Now come the regular sections, i.e. sets of actions, accompanied by URL
+patterns to which they apply. Remember all actions are disabled when matching
+starts, so we have to explicitly enable the ones we want.
+
+The first regular section is probably the most important. It has only one
+pattern, "/", but this pattern matches all URLs. Therefore, the set of actions
+used in this "default" section will be applied to all requests as a start. It
+can be partly or wholly overridden by later matches further down this file, or
+in user.action, but it will still be largely responsible for your overall
+browsing experience.
+
+Again, at the start of matching, all actions are disabled, so there is no real
+need to disable any actions here, but we will do that nonetheless, to have a
+complete listing for your reference. (Remember: a "+" preceding the action name
+enables the action, a "-" disables!). Also note how this long line has been
+made more readable by splitting it into multiple lines with line continuation.
+
+##########################################################################
+# "Defaults" section:
+##########################################################################
+ { \
+ -add-header \
+ -block \
+ -content-type-overwrite \
+ -crunch-client-header \
+ -crunch-if-none-match \
+ -crunch-incoming-cookies \
+ -crunch-server-header \
+ -crunch-outgoing-cookies \
+ +deanimate-gifs \
+ -downgrade-http-version \
+ +fast-redirects{check-decoded-url} \
+ +filter{js-annoyances} \
+ -filter{js-events} \
+ +filter{html-annoyances} \
+ -filter{content-cookies} \
+ +filter{refresh-tags} \
+ +filter{unsolicited-popups} \
+ -filter{all-popups} \
+ +filter{img-reorder} \
+ +filter{banners-by-size} \
+ -filter{banners-by-link} \
+ +filter{webbugs} \
+ -filter{tiny-textforms} \
+ +filter{jumping-windows} \
+ -filter{frameset-borders} \
+ -filter{demoronizer} \
+ -filter{shockwave-flash} \
+ -filter{quicktime-kioskmode} \
+ -filter{fun} \
+ -filter{crude-parental} \
+ +filter{ie-exploits} \
+ -filter-client-headers \
+ -filter-server-headers \
+ -force-text-mode \
+ -handle-as-empty-document \
+ -handle-as-image \
+ -hide-accept-language \
+ -hide-content-disposition \
+ -hide-if-modified-since \
+ +hide-forwarded-for-headers \
+ +hide-from-header{block} \
+ +hide-referrer{forge} \
+ -hide-user-agent \
+ -inspect-jpegs \
+ -kill-popups \
+ -limit-connect \
+ +prevent-compression \
+ -overwrite-last-modified \
+ -redirect \
+ -send-vanilla-wafer \
+ -send-wafer \
+ +session-cookies-only \
+ +set-image-blocker{pattern} \
+ -treat-forbidden-connects-like-blocks \
+ }
+ / # forward slash will match *all* potential URL patterns.
+
+The default behavior is now set. Note that some actions, like not hiding the
+user agent, are part of a "general policy" that applies universally and won't
+get any exceptions defined later. Other choices, like not blocking (which is
+understandably the default!) need exceptions, i.e. we need to specify
+explicitly what we want to block in later sections.
+
+The first of our specialized sections is concerned with "fragile" sites, i.e.
+sites that require minimum interference, because they are either very complex
+or very keen on tracking you (and have mechanisms in place that make them
+unusable for people who avoid being tracked). We will simply use our
+pre-defined fragile alias instead of stating the list of actions explicitly:
+
+##########################################################################
+# Exceptions for sites that'll break under the default action set:
+##########################################################################
+
+# "Fragile" Use a minimum set of actions for these sites (see alias above):
+#
+{ fragile }
+.office.microsoft.com # surprise, surprise!
+.windowsupdate.microsoft.com
+
+Shopping sites are not as fragile, but they typically require cookies to log
+in, and pop-up windows for shopping carts or item details. Again, we'll use a
+pre-defined alias:
+
+# Shopping sites:
+#
+{ shop }
+.quietpc.com
+.worldpay.com # for quietpc.com
+.jungle.com
+.scan.co.uk
+
+The fast-redirects action, which we enabled per default above, breaks some
+sites. So disable it for popular sites where we know it misbehaves:
+
+{ -fast-redirects }
+login.yahoo.com
+edit.*.yahoo.com
+.google.com
+.altavista.com/.*(like|url|link):http
+.altavista.com/trans.*urltext=http
+.nytimes.com
+
+It is important that Privoxy knows which URLs belong to images, so that if they
+are to be blocked, a substitute image can be sent, rather than an HTML page.
+Contacting the remote site to find out is not an option, since it would destroy
+the loading time advantage of banner blocking, and it would feed the
+advertisers (in terms of money and information). We can mark any URL as an
+image with the handle-as-image action, and marking all URLs that end in a known
+image file extension is a good start:
+
+##########################################################################
+# Images:
+##########################################################################
+
+# Define which file types will be treated as images, in case they get
+# blocked further down this file:
+#
+{ +handle-as-image }
+/.*\.(gif|jpe?g|png|bmp|ico)$
+
+And then there are known banner sources. They often use scripts to generate the
+banners, so it won't be visible from the URL that the request is for an image.
+Hence we block them and mark them as images in one go, with the help of our
++block-as-image alias defined above. (We could of course just as well use +
+block +handle-as-image here.) Remember that the type of the replacement image
+is chosen by the set-image-blocker action. Since all URLs have matched the
+default section with its +set-image-blocker{pattern} action before, it still
+applies and needn't be repeated:
+
+# Known ad generators:
+#
+{ +block-as-image }
+ar.atwola.com
+.ad.doubleclick.net
+.ad.*.doubleclick.net
+.a.yimg.com/(?:(?!/i/).)*$
+.a[0-9].yimg.com/(?:(?!/i/).)*$
+bs*.gsanet.com
+bs*.einets.com
+.qkimg.net
+
+One of the most important jobs of Privoxy is to block banners. A huge bunch of
+them can be "blocked" by the filter{banners-by-size} action, which we enabled
+above, and which deletes the references to banner images from the pages while
+they are loaded, so the browser doesn't request them anymore, and hence they
+don't need to be blocked here. But this naturally doesn't catch all banners,
+and some people choose not to use filters, so we need a comprehensive list of
+patterns for banner URLs here, and apply the block action to them.
+
+First comes a bunch of generic patterns, which do most of the work, by matching
+typical domain and path name components of banners. Then comes a list of
+individual patterns for specific sites, which is omitted here to keep the
+example short:
+
+##########################################################################
+# Block these fine banners:
+##########################################################################
+{ +block }
+
+# Generic patterns:
+#
+ad*.
+.*ads.
+banner?.
+count*.
+/.*count(er)?\.(pl|cgi|exe|dll|asp|php[34]?)
+/(?:.*/)?(publicite|werbung|rekla(ma|me|am)|annonse|maino(kset|nta|s)?)/
+
+# Site-specific patterns (abbreviated):
+#
+.hitbox.com
+
+You wouldn't believe how many advertisers actually call their banner servers
+ads.company.com, or call the directory in which the banners are stored simply
+"banners". So the above generic patterns are surprisingly effective.
+
+But being very generic, they necessarily also catch URLs that we don't want to
+block. The pattern .*ads. e.g. catches "nasty-ads.nasty-corp.com" as intended,
+but also "downloads.sourcefroge.net" or "adsl.some-provider.net." So here come
+some well-known exceptions to the +block section above.
+
+Note that these are exceptions to exceptions from the default! Consider the URL
+"downloads.sourcefroge.net": Initially, all actions are deactivated, so it
+wouldn't get blocked. Then comes the defaults section, which matches the URL,
+but just deactivates the block action once again. Then it matches .*ads., an
+exception to the general non-blocking policy, and suddenly +block applies. And
+now, it'll match .*loads., where -block applies, so (unless it matches again
+further down) it ends up with no block action applying.
+
+##########################################################################
+# Save some innocent victims of the above generic block patterns:
+##########################################################################
+
+# By domain:
+#
+{ -block }
+adv[io]*. # (for advogato.org and advice.*)
+adsl. # (has nothing to do with ads)
+ad[ud]*. # (adult.* and add.*)
+.edu # (universities don't host banners (yet!))
+.*loads. # (downloads, uploads etc)
+
+# By path:
+#
+/.*loads/
+
+# Site-specific:
+#
+www.globalintersec.com/adv # (adv = advanced)
+www.ugu.com/sui/ugu/adv
- # These shops require pop-ups also
- {shop -kill-popups}
- .dabs.com
- .overclockers.co.uk
-
+Filtering source code can have nasty side effects, so make an exception for our
+friends at sourceforge.net, and all paths with "cvs" in them. Note that -filter
+disables all filters in one fell swoop!
-The "shop" and "fragile" aliases are often used for "problem" sites that
-require most actions to be disabled in order to function properly.
+# Don't filter code!
+#
+{ -filter }
+/.*cvs
+.sourceforge.net
+
+The actual default.action is of course much more comprehensive, but we hope
+this example made clear how it works.
-------------------------------------------------------------------------------
-9. The Filter File
+8.7.2. user.action
+
+So far we are painting with a broad brush by setting general policies, which
+would be a reasonable starting point for many people. Now, you might want to be
+more specific and have customized rules that are more suitable to your personal
+habits and preferences. These would be for narrowly defined situations like
+your ISP or your bank, and should be placed in user.action, which is parsed
+after all other actions files and hence has the last word, over-riding any
+previously defined actions. user.action is also a safe place for your personal
+settings, since default.action is actively maintained by the Privoxy developers
+and you'll probably want to install updated versions from time to time.
+
+So let's look at a few examples of things that one might typically do in
+user.action:
+
+# My user.action file. <fred@foobar.com>
+
+As aliases are local to the actions file that they are defined in, you can't
+use the ones from default.action, unless you repeat them here:
+
+# Aliases are local to the file they are defined in.
+# (Re-)define aliases for this file:
+#
+{{alias}}
+#
+# These aliases just save typing later, and the alias names should
+# be self explanatory.
+#
++crunch-all-cookies = +crunch-incoming-cookies +crunch-outgoing-cookies
+-crunch-all-cookies = -crunch-incoming-cookies -crunch-outgoing-cookies
+ allow-all-cookies = -crunch-all-cookies -session-cookies-only
+ allow-popups = -filter{all-popups} -kill-popups
++block-as-image = +block +handle-as-image
+-block-as-image = -block
+
+# These aliases define combinations of actions that are useful for
+# certain types of sites:
+#
+fragile = -block -crunch-all-cookies -filter -fast-redirects -hide-referrer -kill-popups
+shop = -crunch-all-cookies allow-popups
+
+# Allow ads for selected useful free sites:
+#
+allow-ads = -block -filter{banners-by-size} -filter{banners-by-link}
+
+# Alias for specific file types that are text, but might have conflicting
+# MIME types. We want the browser to force these to be text documents.
+handle-as-text = -filter +-content-type-overwrite{text/plain} +-force-text-mode -hide-content-disposition
+
+
-Any web page can be dynamically modified with the filter file. This
-modification can be removal, or re-writing, of any web page content, including
-tags and non-visible content. The default filter file is oddly enough
-default.filter, located in the config directory.
+Say you have accounts on some sites that you visit regularly, and you don't
+want to have to log in manually each time. So you'd like to allow persistent
+cookies for these sites. The allow-all-cookies alias defined above does exactly
+that, i.e. it disables crunching of cookies in any direction, and the
+processing of cookies to make them only temporary.
-This is potentially a very powerful feature, and requires knowledge of both
-"regular expression" and HTML in order create custom filters. But, there are a
-number of useful filters included with Privoxy for many common situations.
+{ allow-all-cookies }
+ sourceforge.net
+ .yahoo.com
+ .msdn.microsoft.com
+ .redhat.com
-The included example file is divided into sections. Each section begins with
-the FILTER keyword, followed by the identifier for that section, e.g. "FILTER:
-webbugs". Each section performs a similar type of filtering, such as
-"html-annoyances".
+Your bank is allergic to some filter, but you don't know which, so you disable
+them all:
-This file uses regular expressions to alter or remove any string in the target
-page. The expressions can only operate on one line at a time. Some examples
-from the included default default.filter:
+{ -filter }
+ .your-home-banking-site.com
-Stop web pages from displaying annoying messages in the status bar by deleting
-such references:
+Some file types you may not want to filter for various reasons:
- FILTER: html-annoyances
+# Technical documentation is likely to contain strings that might
+# erroneously get altered by the JavaScript-oriented filters:
+#
+.tldp.org
+/(.*/)?selfhtml/
+
+# And this stupid host sends streaming video with a wrong MIME type,
+# so that Privoxy thinks it is getting HTML and starts filtering:
+#
+stupid-server.example.com/
+
+Example of a simple block action. Say you've seen an ad on your favourite page
+on example.com that you want to get rid of. You have right-clicked the image,
+selected "copy image location" and pasted the URL below while removing the
+leading http://, into a { +block } section. Note that { +handle-as-image } need
+not be specified, since all URLs ending in .gif will be tagged as images by the
+general rules as set in default.action anyway:
+
+{ +block }
+ www.example.com/nasty-ads/sponsor.gif
+ another.popular.site.net/more/junk/here/
+
+The URLs of dynamically generated banners, especially from large banner farms,
+often don't use the well-known image file name extensions, which makes it
+impossible for Privoxy to guess the file type just by looking at the URL. You
+can use the +block-as-image alias defined above for these cases. Note that
+objects which match this rule but then turn out NOT to be an image are
+typically rendered as a "broken image" icon by the browser. Use cautiously.
+
+{ +block-as-image }
+ .doubleclick.net
+ .fastclick.net
+ /Realmedia/ads/
+ ar.atwola.com/
+
+Now you noticed that the default configuration breaks Forbes Magazine, but you
+were too lazy to find out which action is the culprit, and you were again too
+lazy to give feedback, so you just used the fragile alias on the site, and --
+whoa! -- it worked. The fragile aliases disables those actions that are most
+likely to break a site. Also, good for testing purposes to see if it is Privoxy
+that is causing the problem or not. We later find other regular sites that
+misbehave, and add those to our personalized list of troublemakers:
+
+{ fragile }
+ .forbes.com
+ mail.example.com
+ .mybank.com
- # New browser windows should be resizeable and have a location and status
- # bar. Make it so.
- #
- s/resizable="?(no|0)"?/resizable=1/ig s/noresize/yesresize/ig
- s/location="?(no|0)"?/location=1/ig s/status="?(no|0)"?/status=1/ig
- s/scrolling="?(no|0|Auto)"?/scrolling=1/ig
- s/menubar="?(no|0)"?/menubar=1/ig
+You like the "fun" text replacements in default.filter, but it is disabled in
+the distributed actions file. (My colleagues on the team just don't have a
+sense of humour, that's why! ;-). So you'd like to turn it on in your private,
+update-safe config, once and for all:
- # The <BLINK> tag was a crime!
- #
- s*<blink>|</blink>**ig
+{ +filter{fun} }
+ / # For ALL sites!
- # Is this evil?
- #
- #s/framespacing="?(no|0)"?//ig
- #s/margin(height|width)=[0-9]*//gi
-
+Note that the above is not really a good idea: There are exceptions to the
+filters in default.action for things that really shouldn't be filtered, like
+code on CVS->Web interfaces. Since user.action has the last word, these
+exceptions won't be valid for the "fun" filtering specified here.
-Just for kicks, replace any occurrence of "Microsoft" with "MicroSuck", and
-have a little fun with topical buzzwords:
+You might also worry about how your favourite free websites are funded, and
+find that they rely on displaying banner advertisements to survive. So you
+might want to specifically allow banners for those sites that you feel provide
+value to you:
- FILTER: fun
+{ allow-ads }
+ .sourceforge.net
+ .slashdot.org
+ .osdn.net
- s/microsoft(?!.com)/MicroSuck/ig
+Note that allow-ads has been aliased to -block, -filter{banners-by-size}, and -
+filter{banners-by-link} above.
- # Buzzword Bingo:
- #
- s/industry-leading|cutting-edge|award-winning/<font color=red><b>BINGO!</b></
-font>/ig
-
+Invoke another alias here to force an over-ride of the MIME type application/
+x-sh which typically would open a download type dialog. In my case, I want to
+look at the shell script, and then I can save it should I choose to.
-Kill those pesky little web-bugs:
+{ handle-as-text }
+ /.*\.sh$
- # webbugs: Squish WebBugs (1x1 invisible GIFs used for user tracking)
- FILTER: webbugs
+user.action is generally the best place to define exceptions and additions to
+the default policies of default.action. Some actions are safe to have their
+default policies set here though. So let's set a default policy to have a
+"blank" image as opposed to the checkerboard pattern for ALL sites. "/" of
+course matches all URL paths and patterns:
- s/<img\s+[^>]*?(width|height)\s*=\s*['"]?1\D[^>]*?(width|height)\s*=\s*['"]?1
-(\D[^>]*?)?>/<!-- Squished WebBug -->/sig
-
+{ +set-image-blocker{blank} }
+/ # ALL sites
-------------------------------------------------------------------------------
-9.1. The +filter Action
+9. Filter Files
+
+On-the-fly text substitutions that can be invoked through the filter action
+need to be defined in a "filter file". Once defined, they can then be invoked
+as an "action". Multiple filter files can be defined through the filterfile
+config directive. The filters as supplied by the developers will be found in
+default.filter. It is recommended that any locally defined or modified filters
+go in a separately defined file such as user.filter.
+
+Typical reasons for doing these kinds of substitutions are to eliminate common
+annoyances in HTML and JavaScript, such as pop-up windows, exit consoles,
+crippled windows without navigation tools, the infamous <BLINK> tag etc, to
+suppress images with certain width and height attributes (standard banner sizes
+or web-bugs), or just to have fun. The possibilities are endless.
+
+Filtering works on any text-based document type, including HTML, JavaScript,
+CSS etc. (all text/* MIME types, except text/plain). Substitutions are made at
+the source level, so if you want to "roll your own" filters, you should first
+be familiar with HTML syntax, and, of course, regular expressions. By default,
+filters are only applied to the raw document content, but can be extended to
+the HTTP headers with the supplemental actions: filter-client-headers and
+filter-server-headers.
+
+Just like the actions files, the filter file is organized in sections, which
+are called filters here. Each filter consists of a heading line, that starts
+with the keyword FILTER:, followed by the filter's name, and a short (one line)
+description of what it does. Below that line come the jobs, i.e. lines that
+define the actual text substitutions. By convention, the name of a filter
+should describe what the filter eliminates. The comment is used in the
+web-based user interface.
+
+Once a filter called name has been defined in the filter file, it can be
+invoked by using an action of the form +filter{name} in any actions file.
+
+A filter header line for a filter called "foo" could look like this:
+
+FILTER: foo Replace all "foo" with "bar"
+
+Below that line, and up to the next header line, come the jobs that define what
+text replacements the filter executes. They are specified in a syntax that
+imitates Perl's s/// operator. If you are familiar with Perl, you will find
+this to be quite intuitive, and may want to look at the PCRS documentation for
+the subtle differences to Perl behaviour. Most notably, the non-standard option
+letter U is supported, which turns the default to ungreedy matching.
+
+If you are new to "Regular Expressions", you might want to take a look at the
+Appendix on regular expressions, and see the Perl manual for the s///
+operator's syntax and Perl-style regular expressions in general. The below
+examples might also help to get you started.
-Filters are enabled with the "+filter" action from within one of the actions
-files. "+filter" requires one parameter, which should match one of the section
-identifiers in the filter file itself. Example:
+-------------------------------------------------------------------------------
- +filter{html-annoyances}
+9.1. Filter File Tutorial
+
+Now, let's complete our "foo" filter. We have already defined the heading, but
+the jobs are still missing. Since all it does is to replace "foo" with "bar",
+there is only one (trivial) job needed:
+
+s/foo/bar/
+
+But wait! Didn't the comment say that all occurrences of "foo" should be
+replaced? Our current job will only take care of the first "foo" on each page.
+For global substitution, we'll need to add the g option:
+
+s/foo/bar/g
+
+Our complete filter now looks like this:
+
+FILTER: foo Replace all "foo" with "bar"
+s/foo/bar/g
+
+Let's look at some real filters for more interesting examples. Here you see a
+filter that protects against some common annoyances that arise from JavaScript
+abuse. Let's look at its jobs one after the other:
+
+FILTER: js-annoyances Get rid of particularly annoying JavaScript abuse
+
+# Get rid of JavaScript referrer tracking. Test page: http://www.randomoddness.com/untitled.htm
+#
+s|(<script.*)document\.referrer(.*</script>)|$1"Not Your Business!"$2|Usg
+
+Following the header line and a comment, you see the job. Note that it uses |
+as the delimiter instead of /, because the pattern contains a forward slash,
+which would otherwise have to be escaped by a backslash (\).
+
+Now, let's examine the pattern: it starts with the text <script.* enclosed in
+parentheses. Since the dot matches any character, and * means: "Match an
+arbitrary number of the element left of myself", this matches "<script",
+followed by any text, i.e. it matches the whole page, from the start of the
+first <script> tag.
+
+That's more than we want, but the pattern continues: document\.referrer matches
+only the exact string "document.referrer". The dot needed to be escaped, i.e.
+preceded by a backslash, to take away its special meaning as a joker, and make
+it just a regular dot. So far, the meaning is: Match from the start of the
+first <script> tag in a the page, up to, and including, the text
+"document.referrer", if both are present in the page (and appear in that
+order).
+
+But there's still more pattern to go. The next element, again enclosed in
+parentheses, is .*</script>. You already know what .* means, so the whole
+pattern translates to: Match from the start of the first <script> tag in a page
+to the end of the last <script> tag, provided that the text "document.referrer"
+appears somewhere in between.
+
+This is still not the whole story, since we have ignored the options and the
+parentheses: The portions of the page matched by sub-patterns that are enclosed
+in parentheses, will be remembered and be available through the variables $1,
+$2, ... in the substitute. The U option switches to ungreedy matching, which
+means that the first .* in the pattern will only "eat up" all text in between "
+<script" and the first occurrence of "document.referrer", and that the second .
+* will only span the text up to the first "</script>" tag. Furthermore, the s
+option says that the match may span multiple lines in the page, and the g
+option again means that the substitution is global.
+
+So, to summarize, the pattern means: Match all scripts that contain the text
+"document.referrer". Remember the parts of the script from (and including) the
+start tag up to (and excluding) the string "document.referrer" as $1, and the
+part following that string, up to and including the closing tag, as $2.
+
+Now the pattern is deciphered, but wasn't this about substituting things? So
+lets look at the substitute: $1"Not Your Business!"$2 is easy to read: The text
+remembered as $1, followed by "Not Your Business!" (including the quotation
+marks!), followed by the text remembered as $2. This produces an exact copy of
+the original string, with the middle part (the "document.referrer") replaced by
+"Not Your Business!".
+
+The whole job now reads: Replace "document.referrer" by "Not Your Business!"
+wherever it appears inside a <script> tag. Note that this job won't break
+JavaScript syntax, since both the original and the replacement are
+syntactically valid string objects. The script just won't have access to the
+referrer information anymore.
+
+We'll show you two other jobs from the JavaScript taming department, but this
+time only point out the constructs of special interest:
+
+# The status bar is for displaying link targets, not pointless blahblah
+#
+s/window\.status\s*=\s*(['"]).*?\1/dUmMy=1/ig
+
+\s stands for whitespace characters (space, tab, newline, carriage return, form
+feed), so that \s* means: "zero or more whitespace". The ? in .*? makes this
+matching of arbitrary text ungreedy. (Note that the U option is not set). The
+['"] construct means: "a single or a double quote". Finally, \1 is a
+back-reference to the first parenthesis just like $1 above, with the difference
+that in the pattern, a backslash indicates a back-reference, whereas in the
+substitute, it's the dollar.
+
+So what does this job do? It replaces assignments of single- or double-quoted
+strings to the "window.status" object with a dummy assignment (using a variable
+name that is hopefully odd enough not to conflict with real variables in
+scripts). Thus, it catches many cases where e.g. pointless descriptions are
+displayed in the status bar instead of the link target when you move your mouse
+over links.
+
+# Kill OnUnload popups. Yummy. Test: http://www.zdnet.com/zdsubs/yahoo/tree/yfs.html
+#
+s/(<body [^>]*)onunload(.*>)/$1never$2/iU
+
+Including the OnUnload event binding in the HTML DOM was a CRIME. When I close
+a browser window, I want it to close and die. Basta. This job replaces the
+"onunload" attribute in "<body>" tags with the dummy word never. Note that the
+i option makes the pattern matching case-insensitive. Also note that ungreedy
+matching alone doesn't always guarantee a minimal match: In the first
+parenthesis, we had to use [^>]* instead of .* to prevent the match from
+exceeding the <body> tag if it doesn't contain "OnUnload", but the page's
+content does.
+
+The last example is from the fun department:
+
+FILTER: fun Fun text replacements
+
+# Spice the daily news:
+#
+s/microsoft(?!\.com)/MicroSuck/ig
+
+Note the (?!\.com) part (a so-called negative lookahead) in the job's pattern,
+which means: Don't match, if the string ".com" appears directly following
+"microsoft" in the page. This prevents links to microsoft.com from being
+trashed, while still replacing the word everywhere else.
+
+# Buzzword Bingo (example for extended regex syntax)
+#
+s* industry[ -]leading \
+| cutting[ -]edge \
+| customer[ -]focused \
+| market[ -]driven \
+| award[ -]winning # Comments are OK, too! \
+| high[ -]performance \
+| solutions[ -]based \
+| unmatched \
+| unparalleled \
+| unrivalled \
+*<font color="red"><b>BINGO!</b></font> \
+*igx
+
+The x option in this job turns on extended syntax, and allows for e.g. the
+liberal use of (non-interpreted!) whitespace for nicer formatting.
+
+You get the idea?
+
+-------------------------------------------------------------------------------
+
+9.2. The Pre-defined Filters
-This would activate that particular filter. Similarly, "+filter" can be turned
-off for selected sites as: "-filter{html-annoyances}". Remember too, all
-actions are off by default, unless they are explicity enabled in one of the
-actions files.
+The distribution default.filter file contains a selection of pre-defined
+filters for your convenience:
+js-annoyances
+
+ The purpose of this filter is to get rid of particularly annoying
+ JavaScript abuse. To that end, it
+
+ + replaces JavaScript references to the browser's referrer information
+ with the string "Not Your Business!". This compliments the
+ hide-referrer action on the content level.
+
+ + removes the bindings to the DOM's unload event which we feel has no
+ right to exist and is responsible for most "exit consoles", i.e. nasty
+ windows that pop up when you close another one.
+
+ + removes code that causes new windows to be opened with undesired
+ properties, such as being full-screen, non-resizeable, without
+ location, status or menu bar etc.
+
+js-events
+
+ This is a very radical measure. It removes virtually all JavaScript event
+ bindings, which means that scripts can not react to user actions such as
+ mouse movements or clicks, window resizing etc, anymore.
+
+ We strongly discourage using this filter as a default since it breaks many
+ legitimate scripts. It is meant for use only on extra-nasty sites (should
+ you really need to go there).
+
+html-annoyances
+
+ This filter will undo many common instances of HTML based abuse.
+
+ The BLINK and MARQUEE tags are neutralized (yeah baby!), and browser
+ windows will be created as resizeable (as of course they should be!), and
+ will have location, scroll and menu bars -- even if specified otherwise.
+
+content-cookies
+
+ Most cookies are set in the HTTP dialog, where they can be intercepted by
+ the crunch-incoming-cookies and crunch-outgoing-cookies actions. But web
+ sites increasingly make use of HTML meta tags and JavaScript to sneak
+ cookies to the browser on the content level.
+
+ This filter disables HTML and JavaScript code that reads or sets cookies.
+ Use it wherever you would also use the cookie crunch actions.
+
+refresh tags
+
+ Disable any refresh tags if the interval is greater than nine seconds (so
+ that redirections done via refresh tags are not destroyed). This is useful
+ for dial-on-demand setups, or for those who find this HTML feature
+ annoying.
+
+unsolicited-popups
+
+ This filter attempts to prevent only "unsolicited" pop-up windows from
+ opening, yet still allow pop-up windows that the user has explicitly chosen
+ to open. It was added in version 3.0.1, as an improvement over earlier such
+ filters.
+
+ Technical note: The filter works by redefining the window.open JavaScript
+ function to a dummy function during the loading and rendering phase of each
+ HTML page access, and restoring the function afterward.
+
+all-popups
+
+ Attempt to prevent all pop-up windows from opening. Note this should be
+ used with more discretion than the above, since it is more likely to break
+ some sites that require pop-ups for normal usage. Use with caution.
+
+img-reorder
+
+ This is a helper filter that has no value if used alone. It makes the
+ banners-by-size and banners-by-link (see below) filters more effective and
+ should be enabled together with them.
+
+banners-by-size
+
+ This filter removes image tags purely based on what size they are.
+ Fortunately for us, many ads and banner images tend to conform to certain
+ standardized sizes, which makes this filter quite effective for ad
+ stripping purposes.
+
+ Occasionally this filter will cause false positives on images that are not
+ ads, but just happen to be of one of the standard banner sizes.
+
+banners-by-link
+
+ This is an experimental filter that attempts to kill any banners if their
+ URLs seem to point to known or suspected click trackers. It is currently
+ not of much value and is not recommended for use by default.
+
+webbugs
+
+ Webbugs are small, invisible images (technically 1X1 GIF images), that are
+ used to track users across websites, and collect information on them. As an
+ HTML page is loaded by the browser, an embedded image tag causes the
+ browser to contact a third-party site, disclosing the tracking information
+ through the requested URL and/or cookies for that third-party domain,
+ without the use ever becoming aware of the interaction with the third-party
+ site. HTML-ized spam also uses a similar technique to verify email
+ addresses.
+
+ This filter removes the HTML code that loads such "webbugs".
+
+tiny-textforms
+
+ A rather special-purpose filter that can be used to enlarge textareas
+ (those multi-line text boxes in web forms) and turn off hard word wrap in
+ them. It was written for the sourceforge.net tracker system where such
+ boxes are a nuisance, but it can be handy on other sites, too.
+
+ It is not recommended to use this filter as a default.
+
+jumping-windows
+
+ Many consider windows that move, or resize themselves to be abusive. This
+ filter neutralizes the related JavaScript code. Note that some sites might
+ not display or behave as intended when using this filter.
+
+frameset-borders
+
+ Some web designers seem to assume that everyone in the world will view
+ their web sites using the same browser brand and version, screen resolution
+ etc, because only that assumption could explain why they'd use static frame
+ sizes, yet prevent their frames from being resized by the user, should they
+ be too small to show their whole content.
+
+ This filter removes the related HTML code. It should only be applied to
+ sites which need it.
+
+demoronizer
+
+ Many Microsoft products that generate HTML use non-standard extensions
+ (read: violations) of the ISO 8859-1 aka Latin-1 character set. This can
+ cause those HTML documents to display with errors on standard-compliant
+ platforms.
+
+ This filter translates the MS-only characters into Latin-1 equivalents. It
+ is not necessary when using MS products, and will cause corruption of all
+ documents that use 8-bit character sets other than Latin-1. It's mostly
+ worthwhile for Europeans on non-MS platforms, if weird garbage characters
+ sometimes appear on some pages, or user agents that don't correct for this
+ on the fly.
+
+shockwave-flash
+
+ A filter for shockwave haters. As the name suggests, this filter strips
+ code out of web pages that is used to embed shockwave flash objects.
+
+quicktime-kioskmode
+
+ Change HTML code that embeds Quicktime objects so that kioskmode, which
+ prevents saving, is disabled.
+
+fun
+
+ Text replacements for subversive browsing fun. Make fun of your favorite
+ Monopolist or play buzzword bingo.
+
+crude-parental
+
+ A demonstration-only filter that shows how Privoxy can be used to delete
+ web content on a keyword basis.
+
+ie-exploits
+
+ A collection of text replacements to disable malicious HTML and JavaScript
+ code that exploits known security holes in Internet Explorer.
+
+ Presently, it only protects against Nimda and a cross-site scripting bug,
+ and would need active maintenance to provide more substantial protection.
+
+site-specifics
+
+ Some web sites have very specific problems, the cure for which doesn't
+ apply anywhere else, or could even cause damage on other sites.
+
+ This is a collection of such site-specific cures which should only be
+ applied to the sites they were intended for, which is what the supplied
+ default.action file does. Users shouldn't need to change anything regarding
+ this filter.
+
-------------------------------------------------------------------------------
-10. Templates
+10. Privoxy's Template Files
+
+All Privoxy built-in pages, i.e. error pages such as the "404 - No Such Domain"
+error page, the "BLOCKED" page and all pages of its web-based user interface,
+are generated from templates. (Privoxy must be running for the above links to
+work as intended.)
+
+These templates are stored in a subdirectory of the configuration directory
+called templates. On Unixish platforms, this is typically /etc/privoxy/
+templates/.
+
+The templates are basically normal HTML files, but with place-holders (called
+symbols or exports), which Privoxy fills at run time. You can edit the
+templates with a normal text editor, should you want to customize them. (Not
+recommended for the casual user). Note that just like in configuration files,
+lines starting with # are ignored when the templates are filled in.
+
+The place-holders are of the form @name@, and you will find a list of available
+symbols, which vary from template to template, in the comments at the start of
+each file. Note that these comments are not always accurate, and that it's
+probably best to look at the existing HTML code to find out which symbols are
+supported and what they are filled in with.
+
+A special application of this substitution mechanism is to make whole blocks of
+HTML code disappear when a specific symbol is set. We use this for many
+purposes, one of them being to include the beta warning in all our user
+interface (CGI) pages when Privoxy is in an alpha or beta development stage:
+
+<!-- @if-unstable-start -->
+
+ ... beta warning HTML code goes here ...
+
+<!-- if-unstable-end@ -->
+
+If the "unstable" symbol is set, everything in between and including
+@if-unstable-start and if-unstable-end@ will disappear, leaving nothing but an
+empty comment:
+
+<!-- -->
-When Privoxy displays one of its internal pages, such as a 404 Not Found error
-page (Privoxy must be running for link to work as intended), it uses the
-appropriate template. On Linux, BSD, and Unix, these are located in /etc/
-privoxy/templates by default. These may be customized, if desired.
-cgi-style.css is used to control the HTML attributes (fonts, etc).
+There's also an if-then-else construct and an #include mechanism, but you'll
+sure find out if you are inclined to edit the templates ;-)
-The default Blocked (Privoxy needs to be running for page to display) banner
-page with the bright red top banner, is called just "blocked". This may be
-customized or replaced with something else if desired.
+All templates refer to a style located at http://config.privoxy.org/
+send-stylesheet. This is, of course, locally served by Privoxy and the source
+for it can be found and edited in the cgi-style.css template.
-------------------------------------------------------------------------------
11. Contacting the Developers, Bug Reporting and Feature Requests
-We value your feedback. However, to provide you with the best support, please
-note the following sections.
+We value your feedback. In fact, we rely on it to improve Privoxy and its
+configuration. However, please note the following hints, so we can provide you
+with the best support:
-------------------------------------------------------------------------------
11.1. Get Support
-To get support, use the Sourceforge Support Forum:
+For casual users, our support forum at SourceForge is probably best suited:
+http://sourceforge.net/tracker/?group_id=11118&atid=211118
- http://sourceforge.net/tracker/?group_id=11118&atid=211118
+All users are of course welcome to discuss their issues on the users mailing
+list, where the developers also hang around.
-------------------------------------------------------------------------------
-11.2. Report bugs
+11.2. Reporting Problems
-To submit bugs, use the Sourceforge Bug Forum:
+"Problems" for our purposes, come in two forms:
- http://sourceforge.net/tracker/?group_id=11118&atid=111118.
+ * Configuration issues, such as ads that slip through, or sites that don't
+ function properly due to one Privoxy "action" or another being turned "on".
+
+ * "Bugs" in the programming code that makes up Privoxy, such as that might
+ cause a crash.
+
+-------------------------------------------------------------------------------
+
+11.2.1. Reporting Ads or Other Configuration Problems
-Make sure that the bug has not already been submitted. Please try to verify
-that it is a Privoxy bug, and not a browser or site bug first. If you are using
-your own custom configuration, please try the stock configs to see if the
-problem is a configuration related bug. And if not using the latest development
-snapshot, please try the latest one. Or even better, CVS sources. Please be
-sure to include the Privoxy version, platform, browser, any pertinent log data,
-any other relevant details (please be specific) and, if possible, some way to
-reproduce the bug.
+Please send feedback on ads that slipped through, innocent images that were
+blocked, sites that don't work properly, and other configuration related
+problem of default.action file, to http://sourceforge.net/tracker/?group_id=
+11118&atid=460288, the Actions File Tracker.
+
+New, improved default.action files may occasionally be made available based on
+your feedback. These will be announced on the ijbswa-announce list and
+available from our the files section of our project page.
-------------------------------------------------------------------------------
-11.3. Request new features
+11.2.2. Reporting Bugs
-To submit ideas on new features, use the Sourceforge feature request forum:
+Please report all bugs only through our bug tracker: http://sourceforge.net/
+tracker/?group_id=11118&atid=111118.
- http://sourceforge.net/tracker/?atid=361118&group_id=11118&func=browse.
+Before doing so, please make sure that the bug has not already been submitted
+and observe the additional hints at the top of the submit form. If already
+submitted, please feel free to add any info to the original report that might
+help to solve the issue.
--------------------------------------------------------------------------------
+Please try to verify that it is a Privoxy bug, and not a browser or site bug
+first. If unsure, try toggling off Privoxy, and see if the problem persists. If
+you are using your own custom configuration, please try the stock configs to
+see if the problem is configuration related.
-11.4. Report ads or other filter problems
+If not using the latest version, the bug may have been found and fixed in the
+meantime. We would appreciate if you could take the time to upgrade to the
+latest version (or even the latest CVS snapshot) and verify your bug.
-You can also send feedback on websites that Privoxy has problems with. Please
-bookmark the following link: "Privoxy - Submit Filter Feedback". Once you surf
-to a page with problems, use the bookmark to send us feedback. We will look
-into the issue as soon as possible.
+Please be sure to provide the following information:
-New, improved default.action files will occasionally be made available based on
-your feedback. These will be announced on the ijbswa-announce list.
+ * The exact Privoxy version of the proxy software (if you got the source from
+ CVS, please also provide the source code revisions as shown in http://
+ config.privoxy.org/show-version).
+
+ * The operating system and versions you run Privoxy on, (e.g. Windows XP
+ SP2), if you are using some kind of Unix flavour, sending the output of
+ "uname -a" should do.
+
+ * The name, platform, and version of the browser you were using (e.g.
+ Internet Explorer v5.5 for Mac).
+
+ * The URL where the problem occurred, or some way for us to duplicate the
+ problem (e.g. http://somesite.example.com/?somethingelse=123).
+
+ * Whether your version of Privoxy is one supplied by the developers of
+ Privoxy via SourceForge, or somewhere else.
+
+ * Whether you are using Privoxy in tandem with another proxy such as Tor. If
+ so, please try disabling the other proxy.
+
+ * Whether you are using a personal firewall product. If so, does Privoxy work
+ without it?
+
+ * Any other pertinent information to help identify the problem such as config
+ or log file excerpts (yes, you should have log file entries for each action
+ taken).
+
+ * Please provide your SF login, or email address, in case we need to contact
+ you.
+
+The appendix of the Privoxy User Manual also has helpful information on
+understanding actions, and action debugging.
-------------------------------------------------------------------------------
-11.5. Other
+11.3. Request New Features
-For any other issues, feel free to use the mailing lists:
-
- http://sourceforge.net/mail/?group_id=11118.
+You are welcome to submit ideas on new features or other proposals for
+improvement through our feature request tracker at http://sourceforge.net/
+tracker/?atid=361118&group_id=11118.
-Anyone interested in actively participating in development and related
-discussions can also join the appropriate mailing list. Archives are available,
-too. See the page on Sourceforge.
+-------------------------------------------------------------------------------
+
+11.4. Other
+
+For any other issues, feel free to use the mailing lists. Technically
+interested users and people who wish to contribute to the project are also
+welcome on the developers list! You can find an overview of all Privoxy-related
+mailing lists, including list archives, at: http://sourceforge.net/mail/?
+group_id=11118.
-------------------------------------------------------------------------------
-12. Copyright and History
+12. Privoxy Copyright, License and History
+
+Copyright © 2001 - 2006 by Privoxy Developers <
+ijbswa-developers@lists.sourceforge.net>
-12.1. Copyright
+Some source code is based on code Copyright © 1997 by Anonymous Coders and
+Junkbusters, Inc. and licensed under the GNU General Public License.
+
+-------------------------------------------------------------------------------
+
+12.1. License
Privoxy is free software; you can redistribute it and/or modify it under the
-terms of the GNU General Public License as published by the Free Software
-Foundation; either version 2 of the License, or (at your option) any later
-version.
+terms of the GNU General Public License, version 2, as published by the Free
+Software Foundation.
This program is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
PARTICULAR PURPOSE. See the GNU General Public License for more details, which
-is available from the Free Software Foundation, Inc, 59 Temple Place - Suite
-330, Boston, MA 02111-1307, USA.
+is available from the Free Software Foundation, Inc, 51 Franklin Street, Fifth
+Floor, Boston, MA 02110-1301, USA
You should have received a copy of the GNU General Public License along with
-this program; if not, write to the Free Software Foundation, Inc., 59 Temple
-Place, Suite 330, Boston, MA 02111-1307 USA.
+this program; if not, write to the
+
+ Free Software
+ Foundation, Inc. 51 Franklin Street, Fifth Floor
+ Boston, MA 02110-1301
+ USA
-------------------------------------------------------------------------------
12.2. History
-Privoxy is evolved, and derived from, the Internet Junkbuster, with many
-improvments and enhancements over the original.
+Along time ago, there was the Internet Junkbuster, by Anonymous Coders and
+Junkbusters Corporation. This saved many users a lot of pain in the early days
+of web advertising and user tracking.
+
+But the web, its protocols and standards, and with it, the techniques for
+forcing ads on users, give up autonomy over their browsing, and for tracking
+them, keeps evolving. Unfortunately, the Internet Junkbuster did not. Version
+2.0.2, published in 1998, was (and is) the last official release available from
+Junkbusters Corporation. Fortunately, it had been released under the GNU GPL,
+which allowed further development by others.
+
+So Stefan Waldherr started maintaining an improved version of the software, to
+which eventually a number of people contributed patches. It could already
+replace banners with a transparent image, and had a first version of pop-up
+killing, but it was still very closely based on the original, with all its
+limitations, such as the lack of HTTP/1.1 support, flexible per-site
+configuration, or content modification. The last release from this effort was
+version 2.0.2-10, published in 2000.
+
+Then, some developers picked up the thread, and started turning the software
+inside out, upside down, and then reassembled it, adding many new features
+along the way.
+
+The result of this is Privoxy, whose first stable version, 3.0, was released
+August, 2002.
+
+-------------------------------------------------------------------------------
+
+12.3. Authors
+
+Current Privoxy Team:
-Junkbuster was originally written by Anonymous Coders and Junkbusters
-Corporation, and was released as free open-source software under the GNU GPL.
-Stefan Waldherr made many improvements, and started the SourceForge project
-Privoxy to rekindle development. There are now several active developers
-contributing. The last stable release of Junkbuster was v2.0.2, which has now
-grown whiskers ;-).
+ Fabian Keil, developer
+ David Schmidt, developer
+
+ Hal Burgiss
+ Ian Cummings
+ Félix Rauch
+ Roland Rosenfeld
+
+Former Privoxy Team Members:
+
+ Johny Agotnes
+ Rodrigo Barbosa
+ Moritz Barsnick
+ Brian Dessent
+ Jon Foster
+ Karsten Hopp
+ Alexander Lazic
+ Daniel Leite
+ Gábor Lipták
+ Adam Lock
+ Guy Laroche
+ Mark Martinec
+ Andreas Oesterhelt
+ Haroon Rafique
+ Georg Sauthoff
+ Thomas Steudten
+ Joerg Strohmayer
+ Rodney Stromlund
+ Sviatoslav Sviridov
+ Sarantis Paskalis
+ Stefan Waldherr
+
+Thanks to the many people who have tested Privoxy, reported bugs, made
+suggestions or contributed in some way. These include (in alphabetical order):
+
+ Ken Arromdee
+ Devin Bayer
+ Reiner Buehl
+ Andrew J. Caines
+ Clifford Caoile
+ Michael T. Davis
+ Mattes Dolak
+ Ulrich Drepper
+ Peter E
+ Aaron Hamid
+ Magnus Holmgren
+ Don Libes
+ Paul Lieverse
+ Jindrich Makovicka
+ David Mediavilla
+ Oliver Stoeneberg
+ Roberto Ragusa
+ Maynard Riley
+ Bart Schelstraete
+ Bobby G. Vinyard
+ Darren Wiebe
+ Jörg Weinmann
+ Oliver Yeoh
+ Jamie Zawinski
+
+Privoxy is based in part on code originally developed by:
+
+ Junkbusters Corp.
+ Anonymous Coders
-------------------------------------------------------------------------------
Other references and sites of interest to Privoxy users:
-http://www.privoxy.org/, The Privoxy Home page.
+http://www.privoxy.org/, the Privoxy Home page.
-http://sourceforge.net/projects/ijbswa, the Project Page for Privoxy on
-Sourceforge.
+http://www.privoxy.org/faq/, the Privoxy FAQ.
-http://p.p/, access Privoxy from your browser. Alternately, http://
-config.privoxy.org may work in some situations where the first does not.
+http://sourceforge.net/projects/ijbswa/, the Project Page for Privoxy on
+SourceForge.
-http://p.p/, and select "Privoxy - Submit Filter Feedback" to submit "misses"
-to the developers.
+http://config.privoxy.org/, the web-based user interface. Privoxy must be
+running for this to work. Shortcut: http://p.p/
-http://www.junkbusters.com/ht/en/cookies.html
+http://sourceforge.net/tracker/?group_id=11118&atid=460288, to submit "misses"
+and other configuration related suggestions to the developers.
-http://www.waldherr.org/junkbuster/
+http://www.junkbusters.com/ht/en/cookies.html, an explanation how cookies are
+used to track web users.
-http://privacy.net/analyze/
+http://www.junkbusters.com/ijb.html, the original Internet Junkbuster.
-http://www.squid-cache.org/
+http://privacy.net/, a useful site to check what information about you is
+leaked while you browse the web.
-
+http://www.squid-cache.org/, a very popular caching proxy, which is often used
+together with Privoxy.
+
+http://tor.eff.org/, Tor can help anonymize web browsing, web publishing,
+instant messaging, IRC, SSH, and other applications.
+
+http://www.privoxy.org/developer-manual/, the Privoxy developer manual.
-------------------------------------------------------------------------------
14.1. Regular Expressions
-Privoxy can use "regular expressions" in various config files. Assuming support
-for "pcre" (Perl Compatible Regular Expressions) is compiled in, which is the
-default. Such configuration directives do not require regular expressions, but
-they can be used to increase flexibility by matching a pattern with wild-cards
-against URLs.
+Privoxy uses Perl-style "regular expressions" in its actions files and filter
+file, through the PCRE and PCRS libraries.
If you are reading this, you probably don't understand what "regular
expressions" are, or what they can do. So this will be a very brief
introduction only. A full explanation would require a book ;-)
-"Regular expressions" is a way of matching one character expression against
-another to see if it matches or not. One of the "expressions" is a literal
-string of readable characters (letter, numbers, etc), and the other is a
-complex string of literal characters combined with wild-cards, and other
-special characters, called meta-characters. The "meta-characters" have special
-meanings and are used to build the complex pattern to be matched against. Perl
-Compatible Regular Expressions is an enhanced form of the regular expression
-language with backward compatibility.
+Regular expressions provide a language to describe patterns that can be run
+against strings of characters (letter, numbers, etc), to see if they match the
+string or not. The patterns are themselves (sometimes complex) strings of
+literal characters, combined with wild-cards, and other special characters,
+called meta-characters. The "meta-characters" have special meanings and are
+used to build complex patterns to be matched against. Perl Compatible Regular
+Expressions are an especially convenient "dialect" of the regular expression
+language.
To make a simple analogy, we do something similar when we use wild-card
characters when listing files with the dir command in DOS. *.* matches all
\.com", makes sure the period is recognized only as a period (and not expanded
to its meta-character meaning of any single character).
-[] - Characters enclosed in brackets will be matched if any of the enclosed
+[ ] - Characters enclosed in brackets will be matched if any of the enclosed
characters are encountered. For instance, "[0-9]" matches any numeric digit
(zero through nine). As an example, we can combine this with "+" to match any
digit one of more times: "[0-9]+".
-() - parentheses are used to group a sub-expression, or multiple
+( ) - parentheses are used to group a sub-expression, or multiple
sub-expressions.
| - The "bar" character works like an "or" conditional statement. A match is
"/(this|that) example/" uses grouping and the bar character and would match
either "this example" or "that example", and nothing else.
-s/string1/string2/g - This is used to rewrite strings of text. "string1" is
-replaced by "string2" in this example. There must of course be a match on
-"string1" first.
-
These are just some of the ones you are likely to use when matching URLs with
Privoxy, and is a long way from a definitive list. This is enough to get us
started with a few simple examples which may be more illuminating:
banners/annoying.html", or almost an infinite number of other possible
combinations, just so it has "banners" in the path somewhere.
-A now something a little more complex:
+And now something a little more complex:
/.*/adv((er)?ts?|ertis(ing|ements?))?/ - We have several literal forward
slashes again ("/"), so we are building another expression that is a file path
would then match either spelling.
/.*/advert[0-9]+\.(gif|jpe?g) - Again another path statement with forward
-slashes. Anything in the square brackets "[]" can be matched. This is using
+slashes. Anything in the square brackets "[ ]" can be matched. This is using
"0-9" as a shorthand expression to mean any digit one through nine. It is the
same as saying "0123456789". So any digit matches. The "+" means one or more of
the preceding expression must be included. The preceding expression here is
"advert1.gif" (no leading slash), or "/adverts232.jpg" (the expression does not
include an "s"), or "/advert1.jsp" ("jsp" is not in the expression anywhere).
-s/microsoft(?!.com)/MicroSuck/i - This is a substitution. "MicroSuck" will
-replace any occurrence of "microsoft". The "i" at the end of the expression
-means ignore case. The "(?!.com)" means the match should fail if "microsoft" is
-followed by ".com". In other words, this acts like a "NOT" modifier. In case
-this is a hyperlink, we don't want to break it ;-).
-
We are barely scratching the surface of regular expressions here so that you
can understand the default Privoxy configuration files, and maybe use this
knowledge to customize your own installation. There is much, much more that can
be done with regular expressions. Now that you know enough to get started, you
can learn more on your own :/
-More reading on Perl Compatible Regular expressions: http://www.perldoc.com/
-perl5.6/pod/perlre.html
+More reading on Perl Compatible Regular expressions: http://perldoc.perl.org/
+perlre.html
+
+For information on regular expression based substitutions and their
+applications in filters, please see the filter file tutorial in this manual.
-------------------------------------------------------------------------------
http://config.privoxy.org/
- Alternately, this may be reached at http://p.p/, but this variation may not
- work as reliably as the above in some configurations.
+ There is a shortcut: http://p.p/ (But it doesn't provide a fall-back to a
+ real page, in case the request is not sent through Privoxy)
* Show information about the current configuration, including viewing and
editing of actions files:
* Privoxy- View Status
- * Privoxy - Submit Filter Feedback
+ * Privoxy - Why?
-Credit: The site which gave me the general idea for these bookmarklets is
+Credit: The site which gave us the general idea for these bookmarklets is
www.bookmarklets.com. They have more information about bookmarklets.
-------------------------------------------------------------------------------
* First, the server headers are read and processed to determine, among other
things, the MIME type (document type) and encoding. The headers are then
- filtered as deterimed by the "+prevent-setting-cookies",
+ filtered as determined by the "+crunch-incoming-cookies",
"+session-cookies-only", and "+downgrade-http-version" actions.
* If the "+kill-popups" action applies, and it is an HTML or JavaScript
* If a "+filter" or "+deanimate-gifs" action applies (and the document type
fits the action), the rest of the page is read into memory (up to a
- configurable limit). Then the filter rules (from default.filter) are
- processed against the buffered content. Filters are applied in the order
- they are specified in the default.filter file. Animated GIFs, if present,
- are reduced to either the first or last frame, depending on the action
- setting.The entire page, which is now filtered, is then sent by Privoxy
- back to your browser.
+ configurable limit). Then the filter rules (from default.filter and any
+ other filter files) are processed against the buffered content. Filters are
+ applied in the order they are specified in one of the filter files.
+ Animated GIFs, if present, are reduced to either the first or last frame,
+ depending on the action setting.The entire page, which is now filtered, is
+ then sent by Privoxy back to your browser.
If neither "+filter" or "+deanimate-gifs" matches, then Privoxy passes the
raw data through to the client browser as it becomes available.
- * As the browser receives the now (probably filtered) page content, it reads
+ * As the browser receives the now (possibly filtered) page content, it reads
and then requests any URLs that may be embedded within the page source,
e.g. ad images, stylesheets, JavaScript, other HTML documents (e.g.
frames), sounds, etc. For each of these objects, the browser issues a new
-------------------------------------------------------------------------------
-14.4. Anatomy of an Action
+14.4. Troubleshooting: Anatomy of an Action
-The way Privoxy applies "actions" and "filters" to any given URL can be
-complex, and not always so easy to understand what is happening. And sometimes
-we need to be able to see just what Privoxy is doing. Especially, if something
-Privoxy is doing is causing us a problem inadvertently. It can be a little
-daunting to look at the actions and filters files themselves, since they tend
-to be filled with "regular expressions" whose consequences are not always so
-obvious.
+The way Privoxy applies actions and filters to any given URL can be complex,
+and not always so easy to understand what is happening. And sometimes we need
+to be able to see just what Privoxy is doing. Especially, if something Privoxy
+is doing is causing us a problem inadvertently. It can be a little daunting to
+look at the actions and filters files themselves, since they tend to be filled
+with regular expressions whose consequences are not always so obvious.
One quick test to see if Privoxy is causing a problem or not, is to disable it
temporarily. This should be the first troubleshooting step. See the
Bookmarklets section on a quick and easy way to do this (be sure to flush
-caches afterward!).
+caches afterward!). Looking at the logs is a good idea too.
+
+Another easy troubleshooting step to try is if you have done any customization
+of your installation, revert back to the installed defaults and see if that
+helps. There are times the developers get complaints about one thing or
+another, and the problem is more related to a customized configuration issue.
Privoxy also provides the http://config.privoxy.org/show-url-info page that can
show us very specifically how actions are being applied to any given URL. This
First, enter one URL (or partial URL) at the prompt, and then Privoxy will tell
us how the current configuration will handle it. This will not help with
-filtering effects (i.e. the "+filter" action) from the default.filter file
+filtering effects (i.e. the "+filter" action) from one of the filter files
since this is handled very differently and not so easy to trap! It also will
not tell you about any other URLs that may be embedded within the URL you are
testing. For instance, images such as ads are expressed as URLs within the raw
your browser's "View Page Source" option for this. Or right click on the ad,
and grab the URL.
-Let's try an example, google.com, and look at it one section at a time:
-
- Matches for http://google.com:
-
---- File standard ---
-(no matches in this file)
-
---- File default ---
-
-{ -add-header -block +deanimate-gifs{last} -downgrade-http-version +fast-redirects
- -filter{popups} -filter{fun} -filter{shockwave-flash} -filter{crude-parental}
- +filter{html-annoyances} +filter{js-annoyances} +filter{content-cookies}
- +filter{webbugs} +filter{refresh-tags} +filter{nimda} +filter{banners-by-size}
- +hide-forwarded-for-headers +hide-from-header{block} +hide-referer{forge}
- -hide-user-agent -handle-as-image +set-image-blocker{pattern} -limit-connect
- +prevent-compression +session-cookies-only -prevent-reading-cookies
- -prevent-setting-cookies -kill-popups -send-vanilla-wafer -send-wafer }
-/
-
- { -session-cookies-only }
- .google.com
-
- { -fast-redirects }
- .google.com
-
---- File user ---
-(no matches in this file)
-
-This tells us how we have defined our "actions", and which ones match for our
-example, "google.com". The first listing is any matches for the standard.action
-file. No hits at all here on "standard". Then next is "default", or our
-default.action file. The large, multi-line listing, is how the actions are set
-to match for all URLs, i.e. our default settings. If you look at your "actions"
-file, this would be the section just below the "aliases" section near the top.
-This will apply to all URLs as signified by the single forward slash at the end
-of the listing -- "/".
-
-But we can define additional actions that would be exceptions to these general
-rules, and then list specific URLs (or patterns) that these exceptions would
-apply to. Last match wins. Just below this then are two explicit matches for
-".google.com". The first is negating our previous cookie setting, which was for
-"+session-cookies-only" (i.e. not persistent). So we will allow persistent
-cookies for google. The second turns off any "+fast-redirects" action, allowing
-this to take place unmolested. Note that there is a leading dot here --
-".google.com". This will match any hosts and sub-domains, in the google.com
-domain also, such as "www.google.com". So, apparently, we have these two
-actions defined somewhere in the lower part of our default.action file, and
-"google.com" is referenced somewhere in these latter sections.
-
-Then, for our user.action file, we again have no hits.
+Let's try an example, google.com, and look at it one section at a time in a
+sample configuration (your real configuration may vary):
+
+ Matches for http://google.com:
+
+ In file: default.action [ View ] [ Edit ]
+
+ {-add-header
+ -block
+ -content-type-overwrite
+ -crunch-client-header
+ -crunch-if-none-match
+ -crunch-incoming-cookies
+ -crunch-outgoing-cookies
+ -crunch-server-header
+ +deanimate-gifs {last}
+ -downgrade-http-version
+ +fast-redirects {check-decoded-url}
+ -filter {js-events}
+ -filter {content-cookies}
+ -filter {all-popups}
+ -filter {banners-by-link}
+ -filter {tiny-textforms}
+ -filter {frameset-borders}
+ -filter {demoronizer}
+ -filter {shockwave-flash}
+ -filter {quicktime-kioskmode}
+ -filter {fun}
+ -filter {crude-parental}
+ -filter {site-specifics}
+ +filter {js-annoyances}
+ +filter {html-annoyances}
+ +filter {refresh-tags}
+ +filter {unsolicited-popups}
+ +filter {img-reorder}
+ +filter {banners-by-size}
+ +filter {webbugs}
+ +filter {jumping-windows}
+ +filter {ie-exploits}
+ -filter-client-headers
+ -filter-server-headers
+ -force-text-mode
+ -handle-as-empty-document
+ -handle-as-image
+ -hide-accept-language
+ -hide-content-disposition
+ +hide-forwarded-for-headers
+ +hide-from-header {block}
+ -hide-if-modified-since
+ +hide-referrer {forge}
+ -hide-user-agent
+ -inspect-jpegs
+ -kill-popups
+ -limit-connect
+ -overwrite-last-modified
+ +prevent-compression
+ -redirect
+ -send-vanilla-wafer
+ -send-wafer
+ +session-cookies-only
+ +set-image-blocker {pattern}
+ -treat-forbidden-connects-like-blocks }
+/
+
+ { -session-cookies-only }
+ .google.com
+
+ { -fast-redirects }
+ .google.com
+
+In file: user.action [ View ] [ Edit ]
+(no matches in this file)
+
+This is telling us how we have defined our "actions", and which ones match for
+our test case, "google.com". Displayed is all the actions that are available to
+us. Remember, the + sign denotes "on". - denotes "off". So some are "on" here,
+but many are "off". Each example we try may provide a slightly different end
+result, depending on our configuration directives.
+
+The first listing is for our default.action file. The large, multi-line
+listing, is how the actions are set to match for all URLs, i.e. our default
+settings. If you look at your "actions" file, this would be the section just
+below the "aliases" section near the top. This will apply to all URLs as
+signified by the single forward slash at the end of the listing -- " / ".
+
+But we have defined additional actions that would be exceptions to these
+general rules, and then we list specific URLs (or patterns) that these
+exceptions would apply to. Last match wins. Just below this then are two
+explicit matches for ".google.com". The first is negating our previous cookie
+setting, which was for "+session-cookies-only" (i.e. not persistent). So we
+will allow persistent cookies for google, at least that is how it is in this
+example. The second turns off any "+fast-redirects" action, allowing this to
+take place unmolested. Note that there is a leading dot here -- ".google.com".
+This will match any hosts and sub-domains, in the google.com domain also, such
+as "www.google.com" or "mail.google.com". But it would not match
+"www.google.de"! So, apparently, we have these two actions defined as
+exceptions to the general rules at the top somewhere in the lower part of our
+default.action file, and "google.com" is referenced somewhere in these latter
+sections.
+
+Then, for our user.action file, we again have no hits. So there is nothing
+google-specific that we might have added to our own, local configuration. If
+there was, those actions would over-rule any actions from previously processed
+files, such as default.action. user.action typically has the last word. This is
+the best place to put hard and fast exceptions,
And finally we pull it all together in the bottom section and summarize how
Privoxy is applying all its "actions" to "google.com":
- Final results:
- -add-header -block +deanimate-gifs{last} -downgrade-http-version -fast-redirects
- -filter{popups} -filter{fun} -filter{shockwave-flash} -filter{crude-parental}
- +filter{html-annoyances} +filter{js-annoyances} +filter{content-cookies}
- +filter{webbugs} +filter{refresh-tags} +filter{nimda} +filter{banners-by-size}
- +hide-forwarded-for-headers +hide-from-header{block} +hide-referer{forge}
- -hide-user-agent -handle-as-image +set-image-blocker{pattern} -limit-connect
- +prevent-compression -session-cookies-only -prevent-reading-cookies
- -prevent-setting-cookies -kill-popups -send-vanilla-wafer -send-wafer
+ Final results:
+
+ -add-header
+ -block
+ -content-type-overwrite
+ -crunch-client-header
+ -crunch-if-none-match
+ -crunch-incoming-cookies
+ -crunch-outgoing-cookies
+ -crunch-server-header
+ +deanimate-gifs {last}
+ -downgrade-http-version
+ -fast-redirects
+ +filter {js-annoyances}
+ +filter {html-annoyances}
+ +filter {refresh-tags}
+ +filter {unsolicited-popups}
+ +filter {img-reorder}
+ +filter {banners-by-size}
+ +filter {webbugs}
+ +filter {jumping-windows}
+ +filter {ie-exploits}
+ -filter-client-headers
+ -filter-server-headers
+ -force-text-mode
+ -handle-as-empty-document
+ -handle-as-image
+ -hide-accept-language
+ -hide-content-disposition
+ +hide-forwarded-for-headers
+ +hide-from-header {block}
+ -hide-if-modified-since
+ +hide-referrer {forge}
+ -hide-user-agent
+ -inspect-jpegs
+ -kill-popups
+ -limit-connect
+ -overwrite-last-modified
+ +prevent-compression
+ -redirect
+ -send-vanilla-wafer
+ -send-wafer
+ -session-cookies-only
+ +set-image-blocker {pattern}
+ -treat-forbidden-connects-like-blocks
Notice the only difference here to the previous listing, is to "fast-redirects"
-and "session-cookies-only".
+and "session-cookies-only", which are activated specifically for this site in
+our configuration, and thus show in the "Final Results".
Now another example, "ad.doubleclick.net":
- { +block +handle-as-image }
- .ad.doubleclick.net
-
- { +block +handle-as-image }
+ { +block }
ad*.
+ { +block }
+ .ad.
+
{ +block +handle-as-image }
- .doubleclick.net
+ .[a-vx-z]*.doubleclick.net
-We'll just show the interesting part here, the explicit matches. It is matched
-three different times. Each as an "+block +handle-as-image", which is the
-expanded form of one of our aliases that had been defined as: "+imageblock". (
-"Aliases" are defined in the first section of the actions file and typically
-used to combine more than one action.)
+We'll just show the interesting part here - the explicit matches. It is matched
+three different times. Two "+block" sections, and a "+block +handle-as-image",
+which is the expanded form of one of our aliases that had been defined as:
+"+block-as-image". ("Aliases" are defined in the first section of the actions
+file and typically used to combine more than one action.)
Any one of these would have done the trick and blocked this as an unwanted
image. This is unnecessarily redundant since the last case effectively would
also cover the first. No point in taking chances with these guys though ;-)
Note that if you want an ad or obnoxious URL to be invisible, it should be
defined as "ad.doubleclick.net" is done here -- as both a "+block" and an
-"+handle-as-image". The custom alias "+imageblock" just simplifies the process
-and make it more readable.
-
-One last example. Let's try "http://www.rhapsodyk.net/adsl/HOWTO/". This one is
-giving us problems. We are getting a blank page. Hmmm...
-
- Matches for http://www.rhapsodyk.net/adsl/HOWTO/:
-
- { -add-header -block +deanimate-gifs -downgrade-http-version +fast-redirects
- +filter{html-annoyances} +filter{js-annoyances} +filter{kill-popups}
- +filter{webbugs} +filter{nimda} +filter{banners-by-size} +filter{hal}
- +filter{fun} +hide-forwarded-for-headers +hide-from-header{block}
- +hide-referer{forge} -hide-user-agent -handle-as-image +set-image-blocker{blank}
- +prevent-compression +session-cookies-only -prevent-setting-cookies
- -prevent-reading-cookies +kill-popups -send-vanilla-wafer -send-wafer }
- /
-
- { +block +handle-as-image }
- /ads
-
-Ooops, the "/adsl/" is matching "/ads"! But we did not want this at all! Now we
-see why we get the blank page. We could now add a new action below this that
-explicitly does not block ("{-block}") paths with "adsl". There are various
-ways to handle such exceptions. Example:
+"+handle-as-image". The custom alias "+block-as-image" just simplifies the
+process and make it more readable.
+
+One last example. Let's try "http://www.example.net/adsl/HOWTO/". This one is
+giving us problems. We are getting a blank page. Hmmm ...
+
+ Matches for http://www.example.net/adsl/HOWTO/:
+
+ In file: default.action [ View ] [ Edit ]
+
+ {-add-header
+ -block
+ -content-type-overwrite
+ -crunch-client-header
+ -crunch-if-none-match
+ -crunch-incoming-cookies
+ -crunch-outgoing-cookies
+ -crunch-server-header
+ +deanimate-gifs
+ -downgrade-http-version
+ +fast-redirects{check-decoded-url}
+ +filter{html-annoyances}
+ +filter{js-annoyances}
+ +filter{kill-popups}
+ +filter{webbugs}
+ +filter{nimda}
+ +filter{banners-by-size}
+ +filter{hal}
+ +filter{fun}
+ -filter-client-headers
+ -filter-server-headers
+ -force-text-mode
+ -handle-as-empty-document
+ -handle-as-image
+ -hide-accept-language
+ -hide-content-disposition
+ +hide-forwarded-for-headers
+ +hide-from-header{block}
+ +hide-referer{forge}
+ -hide-user-agent
+ -inspect-jpegs
+ +kill-popups
+ -overwrite-last-modified
+ +prevent-compression
+ -redirect
+ -send-vanilla-wafer
+ -send-wafer
+ +session-cookies-only
+ +set-image-blocker{blank}
+ -treat-forbidden-connects-like-blocks }
+ /
+
+ { +block +handle-as-image }
+ /ads
+
+Ooops, the "/adsl/" is matching "/ads" in our configuration! But we did not
+want this at all! Now we see why we get the blank page. It is actually
+triggering two different actions here, and the effects are aggregated so that
+the URL is blocked, and Privoxy is told to treat the block as if it were an
+image. But this is, of course, all wrong. We could now add a new action below
+this (or better in our own user.action file) that explicitly un blocks ( "
+{-block}") paths with "adsl" in them (remember, last match in the configuration
+wins). There are various ways to handle such exceptions. Example:
{ -block }
/adsl
-Now the page displays ;-) Be sure to flush your browser's caches when making
-such changes. Or, try using Shift+Reload.
+Now the page displays ;-) Remember to flush your browser's caches when making
+these kinds of changes to your configuration to insure that you get a freshly
+delivered page! Or, try using Shift+Reload.
But now what about a situation where we get no explicit matches like we did
with:
{ +block +handle-as-image }
/ads
-That actually was very telling and pointed us quickly to where the problem was.
+That actually was very helpful and pointed us quickly to where the problem was.
If you don't get this kind of match, then it means one of the default rules in
-the first section is causing the problem. This would require some guesswork,
-and maybe a little trial and error to isolate the offending rule. One likely
-cause would be one of the "{+filter}" actions. Try adding the URL for the site
-to one of aliases that turn off "+filter":
+the first section of default.action is causing the problem. This would require
+some guesswork, and maybe a little trial and error to isolate the offending
+rule. One likely cause would be one of the "+filter" actions. These tend to be
+harder to troubleshoot. Try adding the URL for the site to one of aliases that
+turn off "+filter":
- {shop}
+ { shop }
.quietpc.com
.worldpay.com # for quietpc.com
.jungle.com
.scan.co.uk
.forbes.com
-"{shop}" is an "alias" that expands to "{ -filter -session-cookies-only }". Or
-you could do your own exception to negate filtering:
+"{ shop }" is an "alias" that expands to "{ -filter -session-cookies-only }".
+Or you could do your own exception to negate filtering:
- {-filter}
+ { -filter }
+ # Disable ALL filter actions for sites in this section
.forbes.com
+ developer.ibm.com
+ localhost
+
+This would turn off all filtering for these sites. This is best put in
+user.action, for local site exceptions. Note that when a simple domain pattern
+is used by itself (without the subsequent path portion), all sub-pages within
+that domain are included automatcially in the scope of the action.
+
+Images that are inexplicably being blocked, may well be hitting the "+filter
+{banners-by-size}" rule, which assumes that images of certain sizes are ad
+banners (works well most of the time since these tend to be standardized).
+
+"{ fragile }" is an alias that disables most actions that are the most likely
+to cause trouble. This can be used as a last resort for problem sites.
+
+ { fragile }
+ # Handle with care: easy to break
+ mail.google.
+ mybank.example.com
-This would probably be most appropriately put in user.action, for local site
-exceptions.
+Remember to flush caches! Note that the mail.google reference lacks the TLD
+portion (e.g. ".com". This will effectively match any TLD with google in it,
+such as mail.google.de, just as an example.
-"{fragile}" is an alias that disables most actions. This can be used as a last
-resort for problem sites. Remember to flush caches! If this still does not
-work, you will have to go through the remaining actions one by one to find
-which one(s) is causing the problem.
+If this still does not work, you will have to go through the remaining actions
+one by one to find which one(s) is causing the problem.
projects / privoxy.git / blobdiff