X-Git-Url: http://www.privoxy.org/gitweb/?p=privoxy.git;a=blobdiff_plain;f=doc%2Fsource%2Fuser-manual.sgml;h=e2a2a7d1515734ef349e870656c317eceaf44e53;hp=3ca6386286661be4de6f0aeef0d1bbea9f3151a2;hb=9e40214d04af75ee0765d4c77145c222d67c3849;hpb=97c15a26185bd3c99025010fd123849545f48cc1 diff --git a/doc/source/user-manual.sgml b/doc/source/user-manual.sgml index 3ca63862..e2a2a7d1 100644 --- a/doc/source/user-manual.sgml +++ b/doc/source/user-manual.sgml @@ -9,8 +9,10 @@ + + @@ -18,6 +20,8 @@ + + ]> + + Copyright &my-copy; 2001, 2002 by + Privoxy Developers + + +$Id: user-manual.sgml,v 1.116 2002/05/17 03:23:46 hal9 Exp $ - + + @@ -98,7 +98,7 @@ Hal. The user manual gives users information on how to install, configure and use Privoxy. - + &p-intro; @@ -109,7 +109,7 @@ Hal. url="http://www.privoxy.org/user-manual/">http://www.privoxy.org/user-manual/. Please see the Contact section on how to contact the developers. - + @@ -173,12 +173,11 @@ Hal. 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 backup your old configuration - if it is valuable to you. See the - note to upgraders section - below. + will need to remove it. On some platforms, this may be done for you as part + of their installation procedure. (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. @@ -188,7 +187,7 @@ How to install the binary packages depends on your operating system: -Red Hat and SuSE RPMs +Red Hat, SuSE RPMs and Conectiva RPMs can be installed with rpm -Uvh privoxy-&p-version;-1.rpm, @@ -326,8 +325,6 @@ automatically start Privoxy in the boot process. &buildsource; - - @@ -347,13 +344,13 @@ automatically start Privoxy in the boot process. and Privoxy configurations will need to be ported. The functionalities of the old blockfile, cookiefile and imagelist - are now combined into the actions - files. + are now combined into the actions + files. default.action, is the main actions file. Local exceptions should best be put into user.action. - A filter file (typically + 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. @@ -397,10 +394,10 @@ automatically start Privoxy in the boot process. - The primary configuration file for cookie management, ad and banner + The primary configuration files 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 + configuration are 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. @@ -425,61 +422,87 @@ automatically start Privoxy in the boot process. - If upgrading, please back up any configuration files. See - the Note to Upgraders Section. - + If upgrading, from versions before 2.9.16, please back up any configuration + files. See the Note to Upgraders Section. + + Install Privoxy. See the Installation Section for platform specific + linkend="installation">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. - 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. + 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 + 127.0.0.1 and port 8118. + (Junkbuster and earlier versions of + Privoxy used port 8000.) See the section Starting Privoxy below + for more details on this. - 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. - + - 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. + + + See the Configuration section for more + configuration options, and how to customize your installation. + next section for a quick + introduction to how Privoxy blocks ads and + banners.]]> - + - If you experience problems with sites that misbehave, see - the Anatomy of an Action section in the - Appendix. + If you experience ads that slipped through, innocent images that are + blocked, or otherwise feel the need to fine-tune + Privoxy's behaviour, 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 Anatomy of an + Action has hints how to debug actions that + misbehave. - + Please see the section Contacting the @@ -488,11 +511,153 @@ automatically start Privoxy in the boot process. + + + Now enjoy surfing with enhanced comfort and privacy! + + + + + +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 blocking is surely common ground for everybody. + + + This section will provide a quick overview 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 recommeneded. + + + 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 a few + 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. + + + Secondly, a quick note on 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. + + + When you connect to a website, the full path of the URL will either match one + of actions as defined in Privoxy's configuration, + or not. If so, then Privoxy will perform the + action accordingly. If not, then nothing special happens. Futhermore, web + pages may contain embedded, secondary URLs that your web browser will + display as it parses the original page's HTML content. An ad image for + instance, is just a 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. If this is the only action that + matches for a particular URL, then Privoxy will + display its own BLOCKED page to let you now what has happened. + + + + + + handle-as-image - + forces Privoxy to treat this URL as if it were + an image. Privoxy knows about common image + types (e.g. GIF), but there are many situations where this does not apply. + So we'll force it. This is particularly important for ad blocking, since + once we can treat it as an image, we can make more intelligent decisisions + on how to handle it. There are some limitations to this though. For + instance, you can't just force an image substituion 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 either be of a known image type, or + match an handle-as-image + action. + + + The configuration options on what to display instead of the ad are: + + + +    pattern - a checkboard 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 URL of the + user's choosing. + + + + + + + + +]]> + + + + Starting <application>Privoxy</application> @@ -500,8 +665,8 @@ automatically start Privoxy in the boot process. 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! + 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! @@ -511,7 +676,7 @@ automatically start Privoxy in the boot process. 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. + 127.0.0.1, Port: 8118). Include if HTTPS proxy support too. @@ -530,7 +695,7 @@ automatically start Privoxy in the boot process. -RedHat and Debian +RedHat, Conectiva and Debian 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 @@ -904,7 +1069,7 @@ must find a better place for this paragraph 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 + default.action (which you 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 @@ -1142,7 +1307,7 @@ actionsfile - Default value: + Default values: @@ -1195,7 +1360,7 @@ actionsfile Specifies: - The filter file to use + The filter file to use @@ -1216,7 +1381,7 @@ actionsfile No textual content filtering takes place, i.e. all - +filter{name} + +filter{name} actions in the actions files are turned neutral. @@ -1225,13 +1390,25 @@ actionsfile 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 + The 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. + + The + +filter{name} + actions rely on the relevant filter (name) + to be defined in the filter file! + + + A pre-defined filter file called default.filter that contains + a bunch of handy filters for common problems is included in the distribution. + See the section on the filter + action for a list. + @@ -1410,8 +1587,8 @@ actionsfile 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. + 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. user-manual @@ -1450,7 +1627,7 @@ actionsfile 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 + The manual itself is normally packaged with the binary distributions, so you probably 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. @@ -1516,7 +1693,7 @@ actionsfile The value of this option only matters if the experimental trust mechanism has been - activated. (See trustfile above.) + activated. (See trustfile above.) If you use the trust mechanism, it is a good idea to write up some on-line @@ -1646,7 +1823,8 @@ actionsfile Specifies: - Key values that determine what information gets logged. + Key values that determine what information gets logged to the + logfile. @@ -1796,14 +1974,14 @@ actionsfile 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 for + 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. @@ -1884,10 +2062,11 @@ actionsfile 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. + 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 @@ -2059,8 +2238,10 @@ ACLs: permit-access and deny-access 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. + Privoxy only 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 @@ -2670,16 +2851,6 @@ forward-socks4 and forward-socks4a - - - 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 @@ -2699,6 +2870,16 @@ forward-socks4 and forward-socks4a thing should go here. This file will not be upgraded. + + + 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. + + @@ -2777,7 +2958,7 @@ forward-socks4 and forward-socks4a - + How Actions are Applied to URLs Actions files are divided into sections. There are special sections, @@ -2812,7 +2993,7 @@ forward-socks4 and forward-socks4a - + Patterns Generally, a pattern has the form <domain>/<path>, @@ -3128,46 +3309,44 @@ forward-socks4 and forward-socks4a -<emphasis>+add-header</emphasis> +<emphasis>add-header</emphasis> - 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: + + + Multi-value. + + + + + Parameter: - Any value is possible. Validity of the defined HTTP headers is not checked. + 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. - - Example usage: - - - {+add-header{X-User-Tracking: sucks}} - .example.com - - - Notes: @@ -3179,177 +3358,215 @@ forward-socks4 and forward-socks4a + + + Example usage: + + + +add-header{X-User-Tracking: sucks} + + + -<emphasis>+block</emphasis> +<emphasis>block</emphasis> - Type: - + Typical use: - Boolean. + Block ads or other obnoxious 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. + as determined by the handle-as-image + and set-image-blocker 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!). + 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 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. + 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. - 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. + 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 + + + + + - - -<emphasis>+deanimate-gifs</emphasis> + +<emphasis>crunch-incoming-cookies</emphasis> - Type: - + Typical use: - Parameterized. + + Prevent the web server from setting any cookies on your system + - Typical uses: + Effect: - To stop those annoying, distracting animated GIF images. + Deletes any Set-Cookie: HTTP headers from server replies. - Possible values: + Type: + + + Boolean. + + + + + Parameter: - last or first + N/A - Example usage: + Notes: - - {+deanimate-gifs{last}} - .example.com - + + 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. + - Notes: + Example usage: - 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). + +crunch-incoming-cookies - + - -<emphasis>+downgrade-http-version</emphasis> + +<emphasis>crunch-outgoing-cookies</emphasis> - Type: - + Typical use: - Boolean. + + Prevent the web server from reading any cookies from your system + - Typical uses: + Effect: - +downgrade-http-version will downgrade HTTP/1.1 client requests to - HTTP/1.0 and downgrade the responses as well. + Deletes any Cookie: HTTP headers from client requests. - Possible values: + Type: + + + Boolean. + + + + + Parameter: N/A @@ -3358,23 +3575,27 @@ forward-socks4 and forward-socks4a - Example usage: + Notes: - - {+downgrade-http-version} - .example.com - + + 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. + - Notes: + Example usage: - 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. + +crunch-outgoing-cookies @@ -3382,463 +3603,467 @@ forward-socks4 and forward-socks4a + - -<emphasis>+fast-redirects</emphasis> + +<emphasis>deanimate-gifs</emphasis> - Type: - + Typical use: - Boolean. + Stop those annoying, distracting animated GIF images. - Typical uses: + Effect: - 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). + De-animate GIF animations, i.e. reduce them to their first or last image. - Possible values: + Type: + + + Parameterized. + + + + + Parameter: - N/A + last or first - Example usage: + Notes: - - {+fast-redirects} - .example.com - + + 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. + - Notes: + Example usage: - - 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. - - - 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. - - - This is a normally on feature, and often requires exceptions - for sites that are sensitive to defeating this mechanism. - + + +deanimate-gifs{last} + - - - -<emphasis>+filter</emphasis> + +<emphasis>downgrade-http-version</emphasis> - Type: - + Typical use: - Parameterized. + Work around (very rare) problems with HTTP/1.1 - Typical uses: + Effect: - 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. + Downgrades HTTP/1.1 client requests and server replies to HTTP/1.0. - Possible values: + Type: + + + Boolean. + + + + + Parameter: - +filter must include the name of one of the section identifiers - from default.filter (or whatever - filterfile is specified in config). + N/A - - Example usage (from the current default.filter): + + Notes: - - - - +filter{html-annoyances}: Get rid of particularly annoying HTML abuse. - - - - - - +filter{js-annoyances}: Get rid of particularly annoying JavaScript abuse - - - - - - +filter{content-cookies}: Kill cookies that come in the HTML or JS content - - - - - - +filter{popups}: Kill all popups in JS and HTML - - - - - - +filter{frameset-borders}: Give frames a border and make them resizable - - - - - - +filter{webbugs}: Squish WebBugs (1x1 invisible GIFs used for user tracking) - - - - - - +filter{refresh-tags}: Kill automatic refresh tags (for dial-on-demand setups) - - - - - - +filter{fun}: Text replacements for subversive browsing fun! - - - - - - +filter{nimda}: Remove Nimda (virus) code. - - - - - - +filter{banners-by-size}: Kill banners by size (very efficient!) - - - - - - +filter{shockwave-flash}: Kill embedded Shockwave Flash objects - - - - - - +filter{crude-parental}: Kill all web pages that contain the words "sex" or "warez" - - + + 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. + - Notes: + Example usage (section): - - 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. - - - Filtering requires buffering the page content, which may appear to - slow down page rendering since nothing is displayed until all content has - passed the filters. (It does not really take longer, but seems that way - since the 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. - + + {+downgrade-http-version} +problem-host.example.com + - - -<emphasis>+hide-forwarded-for-headers</emphasis> + +<emphasis>fast-redirects</emphasis> - Type: - + Typical use: - Boolean. + Fool some click-tracking scripts and speed up indirect links - Typical uses: + Effect: - Block any existing X-Forwarded-for HTTP header, and do not add a new one. + Cut off all but the last valid URL from requests. - Possible values: + Type: + - - N/A - + Boolean. - + - Example usage: + Parameter: - - {+hide-forwarded-for-headers} - .example.com - + + N/A + Notes: + + 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://some.place/click-tracker.cgi?target=http://some.where.else. + + + 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. + - It is fairly safe to leave this on. It does not seem to break many sites. + This feature is currently not very smart and is scheduled for improvement. + It is likely to break some sites. You should expect to need possibly + many exceptions to this action, if it is enabled by default in + default.action. Some sites just don't work without + it. + + Example usage: + + + {+fast-redirects} + + + + - -<emphasis>+hide-from-header</emphasis> + +<emphasis>filter</emphasis> - Type: - + Typical use: - Parameterized. + Get rid of HTML and JavaScript annoyances, banner advertisements (by size), do fun text replacements, etc. - Typical uses: + Effect: - To block the browser from sending your email address in a From: - header. + Text documents, including HTML and JavaScript, to which this action applies, are filtered on-the-fly + through the specified regular expression based substitutions. - Possible values: + Type: + + + Parameterized. + + + + + Parameter: - Keyword: block, or any user defined value. + The name of a filter, as defined in the filter file + (typically default.filter, set by the + filterfile + option in the config file) - Example usage: + Notes: - - {+hide-from-header{block}} - .example.com - + + For your convenience, there are a bunch of pre-defined filters available + in the distribution filter file that you can use. See the example below for + a list. + + + This is potentially a very powerful feature! But rolling your own + filters requires a knowledge of regular expressions and HTML. + + + Filtering requires buffering the page content, which may appear to + slow down page rendering since nothing is displayed until all content has + passed the filters. (It does not really take longer, but seems that way + since the page is not incrementally displayed.) This effect will be more + noticeable on slower connections. + + + At this time, Privoxy cannot (yet!) 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 effects as the + block + action, i.e. it can be used to block ads and banners. + + + Feedback with suggestions for new or improved filters is particularly + welcome! + - Notes: + Example usage (with filters from the distribution default.filter file): - 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. + + +filter{html-annoyances} # Get rid of particularly annoying HTML abuse. + + + + +filter{js-annoyances} # Get rid of particularly annoying JavaScript abuse + + + + +filter{banners-by-size} # Kill banners by size (very efficient!) + + + + +filter{content-cookies} # Kill cookies that come sneaking in the HTML or JS content + + + + +filter{popups} # Kill all popups in JS and HTML + + + + +filter{webbugs} # Squish WebBugs (1x1 invisible GIFs used for user tracking) + + + + +filter{fun} # Text replacements for subversive browsing fun! + + + + +filter{frameset-borders} # Give frames a border and make them resizeable + + + + +filter{refresh-tags} # Kill automatic refresh tags (for dial-on-demand setups) + + + + +filter{nimda} # Remove Nimda (virus) code. + + + + +filter{shockwave-flash} # Kill embedded Shockwave Flash objects + + + + +filter{crude-parental} # Kill all web pages that contain the words "sex" or "warez" - - -<emphasis>+hide-referer</emphasis> - + +<emphasis>handle-as-image</emphasis> + - Type: - + Typical use: - Parameterized. + Mark URLs as belonging to images (so they'll be replaced by images if they get blocked) - Typical uses: + Effect: - Don't send the Referer: (sic) HTTP header to the web site. - Or, alternately send a forged header instead. + 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. - Possible values: + Type: + - - 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. - + Boolean. - + - Example usage: + Parameter: - - {+hide-referer{forge}} - .example.com - + + N/A + - + Notes: - forge is the preferred option here, since some servers will - not send images back otherwise. + 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, (inline) 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. - - +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.) - - - - - - - - - - -<emphasis>+hide-user-agent</emphasis> - - - - Type: - - - Parameterized. - Typical uses: + Example usage (sections): - To change the User-Agent: header so web servers can't tell - your browser type. Who's business is it anyway? - - - + # Generic image extensions: +# +{+handle-as-image} +/.*\.(gif|jpg|jpeg|png|bmp|ico)$ - - Possible values: - - - Any user defined string. +# 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 + - + + + + + + +<emphasis>hide-forwarded-for-headers</emphasis> + + - Example usage: + Typical use: - - {+hide-user-agent{Netscape 6.1 (X11; I; Linux 2.4.18 i686)}} - .msn.com - + Improve privacy by hiding the true source of the request - Notes: + Effect: - 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. + Deletes any existing X-Forwarded-for: HTTP header from client requests, + and prevents adding a new one. - - - - - -<emphasis>+handle-as-image</emphasis> - - Type: @@ -3848,18 +4073,7 @@ forward-socks4 and forward-socks4a - Typical uses: - - - To define what Privoxy should treat - automatically as an image, and is an important ingredient of how - ads are handled. - - - - - - Possible values: + Parameter: N/A @@ -3867,402 +4081,471 @@ forward-socks4 and forward-socks4a - - Example usage: - - - {+handle-as-image} - /.*\.(gif|jpg|jpeg|png|bmp|ico) - - - - Notes: - This only has meaning if the URL (or pattern) also is - +blocked, 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.) + It is fairly safe to leave this on. - There is little reason to change the default definition for this action. + 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-forwarded-for-headers + + + - -<emphasis>+set-image-blocker</emphasis> + +<emphasis>hide-from-header</emphasis> - Type: - + Typical use: - Parameterized. + Keep your (old and ill) browser from telling web servers your email address - Typical uses: + Effect: - Decide what to do with URLs that end up tagged with both - +block - and +handle-as-image, - e.g an advertisement. + Deletes any existing From: HTTP header, or replaces it with the + specified string. - Possible values: + Type: + + + Parameterized. + + + + + Parameter: - 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. + Keyword: block, or any user defined value. - Example usage: + Notes: - - {+set-image-blocker{blank}} - .example.com - + + 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. + + + This action is rarely needed, as modern web browsers don't send + From: headers anymore. + - Notes: + Example usage: - 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. + +hide-from-header{block} or + +hide-from-header{spam-me-senseless@sittingduck.example.com} - - - -<emphasis>+limit-connect</emphasis> + + +<emphasis>hide-referrer</emphasis> + - Type: - + Typical use: - Parameterized. + Conceal which link you followed to get to a particular site - Typical uses: + Effect: - 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. + Deletes the Referer: (sic) HTTP header from the client request, + or replaces it with a forged one. - Possible values: + Type: + - - Any valid port number, or port number range. - + Parameterized. - + - Example usages: + Parameter: - - - - - +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. - + + + block to delete the header completely. + + + 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: - 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. - - - 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). - - - If you don't know what any of this means, there probably is no reason to - change this one. + forge is the preferred option here, since some servers will + not send images back otherwise, in an attempt to prevent their valuable + content from being embedded elsewhere (and hence, without being surrounded + by their banners). + + + 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-referrer{forge} or + +hide-referrer{http://www.yahoo.com/} + + + + - -<emphasis>+prevent-compression</emphasis> + +<emphasis>hide-user-agent</emphasis> - Type: - + Typical use: - Boolean. + Conceal your type of browser and client operating system - Typical uses: + Effect: - Prevent the specified websites from compressing HTTP data. + Replaces the value of the User-Agent: HTTP header + in client requests with the specified value. - Possible values: + Type: + + + Parameterized. + + + + + Parameter: - N/A + Any user-defined string. - Example usage: + Notes: - - {+prevent-compression} - .example.com - - + + + This breaks many web sites that depend on looking at this header in order + to customize their content for different browsers (which, by the + way, is NOT a smart way to do + that!). + + + + 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. + + - Notes: + Example usage: - 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. + +hide-user-agent{Netscape 6.1 (X11; I; Linux 2.4.18 i686)} - + - -<emphasis>+session-cookies-only</emphasis> + +<emphasis>kill-popups<anchor id="kill-popup"></emphasis> - Type: - + Typical use: - Boolean. + Eliminate those annoying pop-up windows - Typical uses: + Effect: - Allow cookies for the current browser session only. + While loading the document, replace JavaScript code that opens + pop-up windows with (syntactically neutral) dummy code on the fly. - 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. + This action is easily confused with the built-in, hardwired 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{popups} + does. + + + 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 is a dangerous business. Many shops and banks rely on + pop-ups to display forms, shopping carts etc, and killing only the unwanted pop-ups + would require artificial intelligence in Privoxy. + 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: + + +kill-popups + + - -<emphasis>+prevent-reading-cookies</emphasis> + +<emphasis>limit-connect</emphasis> - Type: - + Typical use: - Boolean. + Prevent abuse of Privoxy as a TCP proxy relay - Typical uses: + Effect: - Explicitly prevent the web server from reading any cookies on your - system. + Specifies to which ports HTTP CONNECT requests are allowable. - Possible values: + Type: + - - N/A - + Parameterized. - + - Example usage: + Parameter: - - {+prevent-reading-cookies} - .example.com - + + 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: - 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). + 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. - 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. - + 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. + + + If you don't know what any of this means, there probably is no reason to + change this one, since the default is already very restrictive. + + + Example usages: + + + + + + +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 (gaping security hole!) + + + - - -<emphasis>+prevent-setting-cookies</emphasis> + +<emphasis>prevent-compression</emphasis> - Type: - + Typical use: - Boolean. + + Ensure that servers send the content uncompressed, so it can be + passed through filters + - Typical uses: + Effect: - Explicitly block the web server from storing cookies on your - system. + Adds a header to the request that asks for uncompressed transfer. - Possible values: + Type: + + + Boolean. + + + + + Parameter: N/A @@ -4271,21 +4554,45 @@ forward-socks4 and forward-socks4a - Example usage: + Notes: - - {+prevent-setting-cookies} - .example.com - + + 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. + - Notes: + Example usage (sections): - Often used in conjunction with +prevent-reading-cookies to - disable cookies completely (see above). + # Set default: +# +{+prevent-compression} +/ # Match all sites + +# Make exceptions for ill sites: +# +{-prevent-compression} +www.debianhelp.org +www.pclinuxonline.com @@ -4295,29 +4602,40 @@ forward-socks4 and forward-socks4a - -<emphasis>+kill-popups<anchor id="kill-popups"></emphasis> + +<emphasis>send-vanilla-wafer</emphasis> + - Type: - + Typical use: - Boolean. + + Feed log analysis scripts with useless data. + - Typical uses: + Effect: - Stop those annoying JavaScript pop-up windows! + 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: + + + Boolean. + + + + + Parameter: + N/A @@ -4325,31 +4643,23 @@ forward-socks4 and forward-socks4a - Example usage: + Notes: - - {+kill-popups} - .example.com - + + 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. + - Notes: + Example usage: - +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}. - - @@ -4358,100 +4668,219 @@ forward-socks4 and forward-socks4a - -<emphasis>+send-vanilla-wafer</emphasis> + +<emphasis>send-wafer</emphasis> - Type: - + Typical use: - Boolean. + + Send custom cookies or feed log analysis scripts with even more useless data. + - Typical uses: + Effect: - 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. + Sends a custom, user-defined cookie with each request. - Possible values: + Type: + + + Multi-value. + + + + + Parameter: - N/A + A string of the form name=value. - Example usage: + Notes: - - {+send-vanilla-wafer} - .example.com - + + Being multi-valued, multiple instances of this action can apply to the same request, + resulting in multiple cookies being sent. + + + This action is rarely used and not enabled in the default configuration. + - - Notes: + Example usage (section): - 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. + {+send-wafer{UsingPrivoxy=true}} +my-internal-testing-server.void - - -<emphasis>+send-wafer</emphasis> + +<emphasis>session-cookies-only</emphasis> - Type: - + Typical use: - Multi-value. + + Allow only temporary session cookies (for the current browser session only). + - Typical uses: + Effect: - This allows you to send an arbitrary, user definable cookie. + Deletes the expires field from Set-Cookie: server headers. + Most browsers will not store such cookies permanently and forget them in between sessions. + + Type: + + + Boolean. + + + - Possible values: + Parameter: - User specified cookie name and corresponding value. + N/A + + Notes: + + + 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. + + + 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. + + + 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. + + + 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. + + + + Example usage: - - {+send-wafer{name=value}} - .example.com - + + +session-cookies-only + + + + + + + + + +<emphasis>set-image-blocker</emphasis> + + + + 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: + + + Parameterized. + + + + + Parameter: + + + + + 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). + + + 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. + + + @@ -4459,12 +4888,41 @@ forward-socks4 and forward-socks4a Notes: - This can be specified multiple times in order to add as many cookies as you - like. + The URLs for the built-in images are http://config.privoxy.org/send-banner?type=type, where type is + either blank or pattern. + + + 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: + + + Built-in pattern: + + + +set-image-blocker{pattern} + + + 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} + + + @@ -4481,514 +4939,989 @@ forward-socks4 and forward-socks4a linkend="ACTIONSANAT">Appendix for a brief example on troubleshooting actions. - + + + + + +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 + + # These aliases define combinations of actions + # that are useful for certain types of sites: + # + fragile = -block -crunch-all-cookies -filter -fast-redirects -hide-referer -kill-popups + shop = -crunch-all-cookies -filter{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{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. + + + + + +Actions Files Tutorial + + 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: + + +default.action + + +Every config file should start with a short comment stating its purpose: + + + + # Sample default.action file <developers@privoxy.org> + + + +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: + + + + +########################################################################## +# 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 + +# These aliases define combinations of actions +# that are useful for certain types of sites: +# +fragile = -block -crunch-all-cookies -filter -fast-redirects -hide-referer -kill-popups +shop = mercy-for-cookies -filter{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 \ + -crunch-incoming-cookies \ + -crunch-outgoing-cookies \ + +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-parental} \ + -handle-as-image \ + +hide-forwarded-for-headers \ + +hide-from-header{block} \ + +hide-referrer{forge} \ + -hide-user-agent \ + -kill-popups \ + -limit-connect \ + +prevent-compression \ + -send-vanilla-wafer \ + -send-wafer \ + +session-cookies-only \ + +set-image-blocker{pattern} \ + } + / # 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. + We will also want to make exceptions from our general pop-up-killing, + and use our defined aliases for that. + + + + 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 + + + + Then, there are sites which rely on pop-up windows (yuck!) to work. + Since we made pop-up-killing our default above, we need to make exceptions + now. Mozilla users, who + can turn on smart handling of unwanted pop-ups in their browsers, can + safely choose + -filter{popups} (and + -kill-popups) above + and hence don't need this section. Anyway, disabling an already disabled + action doesn't hurt, so we'll define our exceptions regardless of what was + chosen in the defaults section: + + + + +# These sites require pop-ups too :( +# +{ -kill-popups -filter{popups} } +.dabs.com +.overclockers.co.uk +.deutsche-bank-24.de + + + + 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 are already 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 + + + + 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! + + + + +# Don't filter code! +# +{ -filter } +/.*cvs +.sourceforge.net + + + + The actual default.action is of course more + comprehensive, but we hope this example made clear how it works. + + + + +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'd maybe 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: + + + + - - -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. + +# My user.action file. <fred@foobar.com> - 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. + 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: - 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. + +# (Re-)define aliases for this file: +# +{{alias}} +-crunch-all-cookies = -crunch-incoming-cookies -crunch-outgoing-cookies +mercy-for-cookies = -crunch-all-cookies -session-cookies-only +fragile = -block -crunch-all-cookies -filter -fast-redirects -hide-referer -kill-popups +shop = mercy-for-cookies -filter{popups} -kill-popups +allow-ads = -block -filter{banners-by-size} # (see below) + - - - -# Sample default.action file <developers@privoxy.org> + 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 + mercy-for-cookies alias defined above does exactly + that, i.e. it disables crunching of cookies in any direction, and + processing of cookies to make them temporary. + -# Settings -- Don't change! For internal Privoxy use ONLY. -{{settings}} -for-privoxy-version=3.0 + + +{ mercy-for-cookies } +sunsolve.sun.com +slashdot.org +.yahoo.com +.msdn.microsoft.com +.redhat.com + + + Your bank needs popups and is allergic to some filter, but you don't + know which, so you disable them all: + -########################################################################## -# 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. -########################################################################## + + +{ -filter -kill-popups } +.your-home-banking-site.com + + + + While browsing the web with Privoxy you + noticed some ads that sneaked through, but you were too lazy to + report them through our fine and easy feedback + system, so you have added them here: + -# 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 + + +{ +block } +www.a-popular-site.com/some/unobvious/path +another.popular.site.net/more/junk/here/ + -# Alias to both block and treat as if an image for ad blocking -# purposes. - +imageblock = +block +handle-as-image + + Note that, assuming the banners in the above example have regular image + extensions (most do), + +handle-as-image + need not be specified, since all URLs ending in these extensions will + already have been tagged as images in the relevant section of + default.action by now. + -# Fragile sites should have the minimum changes: - fragile = -block -deanimate-gifs -fast-redirects -filter -hide-referer \ - -prevent-cookies -kill-popups + + Then 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: + -# Shops should be allowed to set persistent cookies - shop = -filter -prevent-cookies -session-cookies-only + + +{ fragile } +.forbes.com + + + 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: + -########################################################################## -# 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. + + +{ +filter{fun} } +/ # For ALL sites! + -########################################################################## -# Default behavior is now set. Now we will define some exceptions to our -# default action policies. -########################################################################## + + 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. + -# 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 + + Finally, you might think 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: + + + +{ allow-ads } +.sourceforge.net +.slashdot.org +.osdn.net + -# 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 + + Note that allow-ads has been aliased to + -block + -filter{banners-by-size} + above. + + + + -# 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 + + +The Filter File -# 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 - - - + + All text substitutions that can be invoked through the + filter action + must first be defined in the filter file, which is typically + called default.filter and which can be + selected through the + filterfile config + option. - 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. + Typical reasons for doing such 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. - Now a few examples of some things that one might do with a - user.action file. + Filtering works on any text-based document type, including plain + text, HTML, JavaScript, CSS etc. (all text/* + MIME types). Substitutions are made at the source level, so if + you want to roll your own filters, you should be + familiar with HTML syntax. - - - - - -# 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 + 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: + -# This site is delicate, and requires kid-glove -# treatment. - { fragile } - .forbes.com - - - + + 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 man page + 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. + + - - -Aliases +Filter File 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. + 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: - Now let's define a few aliases: + s/foo/bar/ - - - - # 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 - - # 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. - - - + 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: - 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): + s/foo/bar/g - - - - # These sites are very complex and require - # minimal interference. - {fragile} - .office.microsoft.com - .windowsupdate.microsoft.com - .nytimes.com - - # Shopping sites - but we still want to block ads. - {shop} - .quietpc.com - .worldpay.com # for quietpc.com - .scan.co.uk - - # These shops require pop-ups also - {shop -kill-popups} - .dabs.com - .overclockers.co.uk - - - + Our complete filter now looks like this: - - The shop and fragile aliases are often used for - problem sites that require most actions to be disabled - in order to function properly. - + 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 (\). + - -The Filter File - 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. + 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. - 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. + 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). - 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. + 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 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: + 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. - Stop web pages from displaying annoying messages in the status bar by - deleting such references: + 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. - - - - FILTER: html-annoyances + 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!". + - # 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 + + 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. + - # The <BLINK> tag was a crime! - # - s*<blink>|</blink>**ig + + We'll show you two other jobs from the JavaScript taming department, but + this time only point out the constructs of special interest: + - # Is this evil? - # - #s/framespacing="?(no|0)"?//ig - #s/margin(height|width)=[0-9]*//gi - - - + + +# The status bar is for displaying link targets, not pointless blahblah +# +s/window\.status\s*=\s*['"].*?['"]/dUmMy=1/ig - Just for kicks, replace any occurrence of Microsoft with - MicroSuck, and have a little fun with topical buzzwords: + \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. - - - - FILTER: fun + 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. + - s/microsoft(?!.com)/MicroSuck/ig + + +# Kill OnUnload popups. Yummy. Test: http://www.zdnet.com/zdsubs/yahoo/tree/yfs.html +# +s/(<body .*)onunload(.*>)/$1never$2/iU + - # Buzzword Bingo: - # - s/industry-leading|cutting-edge|award-winning/<font color=red><b>BINGO!</b></font>/ig - - - + + 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. - Kill those pesky little web-bugs: + The last example is from the fun department: - - - - # webbugs: Squish WebBugs (1x1 invisible GIFs used for user tracking) - FILTER: webbugs + +FILTER: fun Fun text replacements - s/<img\s+[^>]*?(width|height)\s*=\s*['"]?1\D[^>]*?(width|height)\s*=\s*['"]?1(\D[^>]*?)?>/<!-- Squished WebBug -->/sig - - - +# Spice the daily news: +# +s/microsoft(?!\.com)/MicroSuck/ig - - - -The <emphasis>+filter</emphasis> Action - 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: + 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 messed, while + still replacing the word everywhere else. - - +filter{html-annoyances} - + + +# Buzzword Bingo (example for extended regex syntax) +# +s* industry[ -]leading \ +| cutting[ -]edge \ +| award[ -]winning # Comments are OK, too! \ +| high[ -]performance \ +| solutions[ -]based \ +| unmatched \ +| unparalleled \ +| unrivalled \ +*<font color="red"><b>BINGO!</b></font> \ +*igx + - 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 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? + - @@ -5000,23 +5933,82 @@ for-privoxy-version=3.0 Templates - 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). + 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 + in 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: + + + + <!-- --> + + - 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. + 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 ;-) + + + 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. + @@ -5034,16 +6026,15 @@ Requests + + -Copyright, License and History +<application>Privoxy</application> Copyright, License and History -Copyright ©right; - - License @@ -5061,8 +6052,18 @@ Requests &history; + +Authors + + &p-authors; + + + + + + See Also @@ -5080,30 +6081,29 @@ Requests 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 ;-) + 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. @@ -5190,14 +6190,6 @@ Requests - - - 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 @@ -5287,16 +6279,6 @@ Requests 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 @@ -5311,6 +6293,11 @@ Requests http://www.perldoc.com/perl5.6/pod/perlre.html + + For information on regular expression based substititions and their applications + in filters, please see the filter file tutorial + in this manual. + @@ -5353,9 +6340,9 @@ Requests - 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 fallback to a real page, in case the request is not + sent through Privoxy) @@ -5489,17 +6476,15 @@ Requests - Privoxy - Submit Filter Feedback + Privoxy - Submit Actions File Feedback - - - 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. @@ -5537,14 +6522,14 @@ Requests Next, Privoxy checks to see if the URL - matches any +block patterns. If + matches any +block patterns. If so, the URL is then blocked, and the remote web server will not be contacted. - +handle-as-image + +handle-as-image is then checked and if it does not match, an HTML BLOCKED page is sent back. Otherwise, if it does match, - an image is returned. The type of image depends on the setting of +set-image-blocker + an image is returned. The type of image depends on the setting of +set-image-blocker (blank, checkerboard pattern, or an HTTP redirect to an image elsewhere). @@ -5556,16 +6541,16 @@ Requests - If the URL pattern matches the +fast-redirects action, + If the URL pattern matches the +fast-redirects action, it is then processed. Unwanted parts of the requested URL are stripped. Now the rest of the client browser's request headers are processed. If any - of these match any of the relevant actions (e.g. +hide-user-agent, + of these match any of the relevant actions (e.g. +hide-user-agent, etc.), headers are suppressed or forged as determined by these actions and their parameters. @@ -5581,24 +6566,24 @@ Requests 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, - +session-cookies-only, - and +downgrade-http-version + +crunch-incoming-cookies, + +session-cookies-only, + and +downgrade-http-version actions. - If the +kill-popups + If the +kill-popups action applies, and it is an HTML or JavaScript document, the popup-code in the response is filtered on-the-fly as it is received. - If a +filter - or +deanimate-gifs + 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 @@ -5609,9 +6594,9 @@ Requests Privoxy back to your browser. - If neither +filter - or +deanimate-gifs + If neither +filter + or +deanimate-gifs matches, then Privoxy passes the raw data through to the client browser as it becomes available. @@ -5639,16 +6624,15 @@ Requests The way Privoxy applies - actions - and filters + 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. + regular expressions whose consequences are not + always so obvious. @@ -5669,8 +6653,8 @@ Requests 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 + help with filtering effects (i.e. the +filter action) from the default.filter file 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 @@ -5702,8 +6686,8 @@ Requests +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 } + +prevent-compression +session-cookies-only -crunch-outgoing-cookies + -crunch-incoming-cookies -kill-popups -send-vanilla-wafer -send-wafer } / { -session-cookies-only } @@ -5719,7 +6703,7 @@ Requests This tells us how we have defined our - actions, and + 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 @@ -5736,12 +6720,12 @@ Requests 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 + 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 + +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 @@ -5772,8 +6756,8 @@ Requests +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 + +prevent-compression -session-cookies-only -crunch-outgoing-cookies + -crunch-incoming-cookies -kill-popups -send-vanilla-wafer -send-wafer @@ -5804,8 +6788,8 @@ Requests 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 + +imageblock. (Aliases are defined in the first section of the actions file and typically used to combine more than one action.) @@ -5816,11 +6800,11 @@ Requests 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 + is done here -- as both a +block and an - +handle-as-image. + +handle-as-image. The custom alias +imageblock just simplifies the process and make it more readable. @@ -5840,8 +6824,8 @@ Requests +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 } + +prevent-compression +session-cookies-only -crunch-incoming-cookies + -crunch-outgoing-cookies +kill-popups -send-vanilla-wafer -send-wafer } / { +block +handle-as-image } @@ -5956,6 +6940,46 @@ Requests Temple Place - Suite 330, Boston, MA 02111-1307, USA. $Log: user-manual.sgml,v $ + Revision 1.116 2002/05/17 03:23:46 hal9 + Fixing merge conflict in Quickstart section. + + Revision 1.115 2002/05/16 16:25:00 oes + Extended the Filter File chapter & minor fixes + + Revision 1.114 2002/05/16 09:42:50 oes + More ulink->link, added some hints to Quickstart section + + Revision 1.113 2002/05/15 21:07:25 oes + Extended and further commented the example actions files + + Revision 1.112 2002/05/15 03:57:14 hal9 + Spell check. A few minor edits here and there for better syntax and + clarification. + + Revision 1.111 2002/05/14 23:01:36 oes + Fixing the fixes + + Revision 1.110 2002/05/14 19:10:45 oes + Restored alphabetical order of actions + + Revision 1.109 2002/05/14 17:23:11 oes + Renamed the prevent-*-cookies actions, extended aliases section and moved it before the example AFs + + Revision 1.108 2002/05/14 15:29:12 oes + Completed proofreading the actions chapter + + Revision 1.107 2002/05/12 03:20:41 hal9 + Small clarifications for 127.0.0.1 vs localhost for listen-address since this + apparently an important distinction for some OS's. + + Revision 1.106 2002/05/10 01:48:20 hal9 + This is mostly proposed copyright/licensing additions and changes. Docs + are still GPL, but licensing and copyright are more visible. Also, copyright + changed in doc header comments (eliminate references to JB except FAQ). + + Revision 1.105 2002/05/05 20:26:02 hal9 + Sorting out license vs copyright in these docs. + Revision 1.104 2002/05/04 08:44:45 swa bumped version