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-
- <div class="SECT1">
- <h1 class="SECT1"><a name="ACTIONS-FILE" id="ACTIONS-FILE">8. Actions
- Files</a></h1>
-
- <p>The actions files are used to define what <span class=
- "emphasis"><i class="EMPHASIS">actions</i></span> <span class=
- "APPLICATION">Privoxy</span> takes for which URLs, and thus determines
- how ad images, cookies and various other aspects of HTTP content and
- transactions are handled, and on which sites (or even parts thereof).
- There are a number of such actions, with a wide range of functionality.
- Each action does something a little different. These actions give us a
- veritable arsenal of tools with which to exert our control, preferences
- and independence. Actions can be combined so that their effects are
- aggregated when applied against a given set of URLs.</p>
-
- <p>There are three action files included with <span class=
- "APPLICATION">Privoxy</span> with differing purposes:</p>
-
- <ul>
- <li>
- <p><tt class="FILENAME">match-all.action</tt> - is used to define
- which <span class="QUOTE">"actions"</span> relating to
- banner-blocking, images, pop-ups, content modification, cookie
- handling etc should be applied by default. It should be the first
- actions file loaded</p>
- </li>
-
- <li>
- <p><tt class="FILENAME">default.action</tt> - defines many exceptions
- (both positive and negative) from the default set of actions that's
- configured in <tt class="FILENAME">match-all.action</tt>. It is a set
- of rules that should work reasonably well as-is for most users. This
- file is only supposed to be edited by the developers. It should be
- the second actions file loaded.</p>
- </li>
-
- <li>
- <p><tt class="FILENAME">user.action</tt> - is intended to be for
- local site preferences and exceptions. As an example, if your ISP or
- your bank has specific requirements, and need special handling, this
- kind of thing should go here. This file will not be upgraded.</p>
- </li>
-
- <li>
- <p><span class="GUIBUTTON">Edit</span> <span class="GUIBUTTON">Set to
- Cautious</span> <span class="GUIBUTTON">Set to Medium</span>
- <span class="GUIBUTTON">Set to Advanced</span></p>
-
- <p>These have increasing levels of aggressiveness <span class=
- "emphasis"><i class="EMPHASIS">and have no influence on your browsing
- unless you select them explicitly in the editor</i></span>. A default
- installation should be pre-set to <tt class="LITERAL">Cautious</tt>.
- New users should try this for a while before adjusting the settings
- to more aggressive levels. The more aggressive the settings, then the
- more likelihood there is of problems such as sites not working as
- they should.</p>
-
- <p>The <span class="GUIBUTTON">Edit</span> button allows you to turn
- each action on/off individually for fine-tuning. The <span class=
- "GUIBUTTON">Cautious</span> button changes the actions list to
- low/safe settings which will activate ad blocking and a minimal set
- of <span class="APPLICATION">Privoxy</span>'s features, and
- subsequently there will be less of a chance for accidental problems.
- The <span class="GUIBUTTON">Medium</span> button sets the list to a
- medium level of other features and a low level set of privacy
- features. The <span class="GUIBUTTON">Advanced</span> button sets the
- list to a high level of ad blocking and medium level of privacy. See
- the chart below. The latter three buttons over-ride any changes via
- with the <span class="GUIBUTTON">Edit</span> button. More fine-tuning
- can be done in the lower sections of this internal page.</p>
-
- <p>While the actions file editor allows to enable these settings in
- all actions files, they are only supposed to be enabled in the first
- one to make sure you don't unintentionally overrule earlier
- rules.</p>
-
- <p>The default profiles, and their associated actions, as pre-defined
- in <tt class="FILENAME">default.action</tt> are:</p>
-
- <div class="TABLE">
- <a name="AEN2793" id="AEN2793"></a>
-
- <p><b>Table 1. Default Configurations</b></p>
-
- <table border="1" frame="border" rules="all" class="CALSTABLE">
- <col width="1*" title="C1">
- <col width="1*" title="C2">
- <col width="1*" title="C3">
- <col width="1*" title="C4">
-
- <thead>
- <tr>
- <th>Feature</th>
-
- <th>Cautious</th>
-
- <th>Medium</th>
-
- <th>Advanced</th>
- </tr>
- </thead>
-
- <tbody>
- <tr>
- <td>Ad-blocking Aggressiveness</td>
-
- <td>medium</td>
-
- <td>high</td>
-
- <td>high</td>
- </tr>
-
- <tr>
- <td>Ad-filtering by size</td>
-
- <td>no</td>
-
- <td>yes</td>
-
- <td>yes</td>
- </tr>
-
- <tr>
- <td>Ad-filtering by link</td>
-
- <td>no</td>
-
- <td>no</td>
-
- <td>yes</td>
- </tr>
-
- <tr>
- <td>Pop-up killing</td>
-
- <td>blocks only</td>
-
- <td>blocks only</td>
-
- <td>blocks only</td>
- </tr>
-
- <tr>
- <td>Privacy Features</td>
-
- <td>low</td>
-
- <td>medium</td>
-
- <td>medium/high</td>
- </tr>
-
- <tr>
- <td>Cookie handling</td>
-
- <td>none</td>
-
- <td>session-only</td>
-
- <td>kill</td>
- </tr>
-
- <tr>
- <td>Referer forging</td>
-
- <td>no</td>
-
- <td>yes</td>
-
- <td>yes</td>
- </tr>
-
- <tr>
- <td>GIF de-animation</td>
-
- <td>no</td>
-
- <td>yes</td>
-
- <td>yes</td>
- </tr>
-
- <tr>
- <td>Fast redirects</td>
-
- <td>no</td>
-
- <td>no</td>
-
- <td>yes</td>
- </tr>
-
- <tr>
- <td>HTML taming</td>
-
- <td>no</td>
-
- <td>no</td>
-
- <td>yes</td>
- </tr>
-
- <tr>
- <td>JavaScript taming</td>
-
- <td>no</td>
-
- <td>no</td>
-
- <td>yes</td>
- </tr>
-
- <tr>
- <td>Web-bug killing</td>
-
- <td>no</td>
-
- <td>yes</td>
-
- <td>yes</td>
- </tr>
-
- <tr>
- <td>Image tag reordering</td>
-
- <td>no</td>
-
- <td>yes</td>
-
- <td>yes</td>
- </tr>
- </tbody>
- </table>
- </div>
- </li>
- </ul>
-
- <p>The list of actions files to be used are defined in the main
- configuration file, and are processed in the order they are defined (e.g.
- <tt class="FILENAME">default.action</tt> is typically processed before
- <tt class="FILENAME">user.action</tt>). The content of these can all be
- viewed and edited from <a href="http://config.privoxy.org/show-status"
- target="_top">http://config.privoxy.org/show-status</a>. The over-riding
- principle when applying actions, is that the last action that matches a
- given URL wins. The broadest, most general rules go first (defined in
- <tt class="FILENAME">default.action</tt>), followed by any exceptions
- (typically also in <tt class="FILENAME">default.action</tt>), which are
- then followed lastly by any local preferences (typically in <span class=
- "emphasis"><i class="EMPHASIS">user</i></span><tt class=
- "FILENAME">.action</tt>). Generally, <tt class=
- "FILENAME">user.action</tt> has the last word.</p>
-
- <p>An actions file typically has multiple sections. If you want to use
- <span class="QUOTE">"aliases"</span> in an actions file, you have to
- place the (optional) <a href="actions-file.html#ALIASES">alias
- section</a> at the top of that file. Then comes the default set of rules
- which will apply universally to all sites and pages (be <span class=
- "emphasis"><i class="EMPHASIS">very careful</i></span> with using such a
- universal set in <tt class="FILENAME">user.action</tt> or any other
- actions file after <tt class="FILENAME">default.action</tt>, because it
- will override the result from consulting any previous file). And then
- below that, exceptions to the defined universal policies. You can regard
- <tt class="FILENAME">user.action</tt> as an appendix to <tt class=
- "FILENAME">default.action</tt>, with the advantage that it is a separate
- file, which makes preserving your personal settings across <span class=
- "APPLICATION">Privoxy</span> upgrades easier.</p>
-
- <p>Actions can be used to block anything you want, including ads,
- banners, or just some obnoxious URL whose content you would rather not
- see. Cookies can be accepted or rejected, or accepted only during the
- current browser session (i.e. not written to disk), content can be
- modified, some JavaScripts tamed, user-tracking fooled, and much more.
- See below for a <a href="actions-file.html#ACTIONS">complete list of
- actions</a>.</p>
-
- <div class="SECT2">
- <h2 class="SECT2"><a name="RIGHT-MIX" id="RIGHT-MIX">8.1. Finding the
- Right Mix</a></h2>
-
- <p>Note that some <a href="actions-file.html#ACTIONS">actions</a>, like
- cookie suppression or script disabling, may render some sites unusable
- that rely on these techniques to work properly. Finding the right mix
- of actions is not always easy and certainly a matter of personal taste.
- And, things can always change, requiring refinements in the
- configuration. In general, it can be said that the more <span class=
- "QUOTE">"aggressive"</span> your default settings (in the top section
- of the actions file) are, the more exceptions for <span class=
- "QUOTE">"trusted"</span> sites you will have to make later. If, for
- example, you want to crunch all cookies per default, you'll have to
- make exceptions from that rule for sites that you regularly use and
- that require cookies for actually useful purposes, like maybe your
- bank, favorite shop, or newspaper.</p>
-
- <p>We have tried to provide you with reasonable rules to start from in
- the distribution actions files. But there is no general rule of thumb
- on these things. There just are too many variables, and sites are
- constantly changing. Sooner or later you will want to change the rules
- (and read this chapter again :).</p>
- </div>
-
- <div class="SECT2">
- <h2 class="SECT2"><a name="HOW-TO-EDIT" id="HOW-TO-EDIT">8.2. How to
- Edit</a></h2>
-
- <p>The easiest way to edit the actions files is with a browser by using
- our browser-based editor, which can be reached from <a href=
- "http://config.privoxy.org/show-status" target=
- "_top">http://config.privoxy.org/show-status</a>. Note: the config file
- option <a href=
- "config.html#ENABLE-EDIT-ACTIONS">enable-edit-actions</a> must be
- enabled for this to work. The editor allows both fine-grained control
- over every single feature on a per-URL basis, and easy choosing from
- wholesale sets of defaults like <span class="QUOTE">"Cautious"</span>,
- <span class="QUOTE">"Medium"</span> or <span class=
- "QUOTE">"Advanced"</span>. Warning: the <span class=
- "QUOTE">"Advanced"</span> setting is more aggressive, and will be more
- likely to cause problems for some sites. Experienced users only!</p>
-
- <p>If you prefer plain text editing to GUIs, you can of course also
- directly edit the the actions files with your favorite text editor.
- Look at <tt class="FILENAME">default.action</tt> which is richly
- commented with many good examples.</p>
- </div>
-
- <div class="SECT2">
- <h2 class="SECT2"><a name="ACTIONS-APPLY" id="ACTIONS-APPLY">8.3. How
- Actions are Applied to Requests</a></h2>
-
- <p>Actions files are divided into sections. There are special sections,
- like the <span class="QUOTE">"<a href=
- "actions-file.html#ALIASES">alias</a>"</span> sections which will be
- discussed later. For now let's concentrate on regular sections: They
- have a heading line (often split up to multiple lines for readability)
- which consist of a list of actions, separated by whitespace and
- enclosed in curly braces. Below that, there is a list of URL and tag
- patterns, each on a separate line.</p>
-
- <p>To determine which actions apply to a request, the URL of the
- request is compared to all URL patterns in each <span class=
- "QUOTE">"action file"</span>. Every time it matches, the list of
- applicable actions for the request is incrementally updated, using the
- heading of the section in which the pattern is located. The same is
- done again for tags and tag patterns later on.</p>
-
- <p>If multiple applying sections set the same action differently, the
- last match wins. If not, the effects are aggregated. E.g. a URL might
- match a regular section with a heading line of <tt class="LITERAL">{
- +<a href="actions-file.html#HANDLE-AS-IMAGE">handle-as-image</a>
- }</tt>, then later another one with just <tt class="LITERAL">{
- +<a href="actions-file.html#BLOCK">block</a> }</tt>, resulting in
- <span class="emphasis"><i class="EMPHASIS">both</i></span> actions to
- apply. And there may well be cases where you will want to combine
- actions together. Such a section then might look like:</p>
-
- <table border="0" bgcolor="#E0E0E0" width="100%">
+ <head>
+ <title>
+ Actions Files
+ </title>
+ <meta name="GENERATOR" content=
+ "Modular DocBook HTML Stylesheet Version 1.79">
+ <link rel="HOME" title="Privoxy 3.0.26 User Manual" href="index.html">
+ <link rel="PREVIOUS" title="The Main Configuration File" href=
+ "config.html">
+ <link rel="NEXT" title="Filter Files" href="filter-file.html">
+ <link rel="STYLESHEET" type="text/css" href="../p_doc.css">
+ <meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
+ <link rel="STYLESHEET" type="text/css" href="p_doc.css">
+ </head>
+ <body class="SECT1" bgcolor="#EEEEEE" text="#000000" link="#0000FF" vlink=
+ "#840084" alink="#0000FF">
+ <div class="NAVHEADER">
+ <table summary="Header navigation table" width="100%" border="0"
+ cellpadding="0" cellspacing="0">
<tr>
- <td>
- <pre class="SCREEN">
- { +<tt class="LITERAL">handle-as-image</tt> +<tt class=
-"LITERAL">block{Banner ads.}</tt> }
- # Block these as if they were images. Send no block page.
- banners.example.com
- media.example.com/.*banners
- .example.com/images/ads/
-</pre>
- </td>
+ <th colspan="3" align="center">
+ Privoxy 3.0.26 User Manual
+ </th>
</tr>
- </table>
-
- <p>You can trace this process for URL patterns and any given URL by
- visiting <a href="http://config.privoxy.org/show-url-info" target=
- "_top">http://config.privoxy.org/show-url-info</a>.</p>
-
- <p>Examples and more detail on this is provided in the Appendix,
- <a href="appendix.html#ACTIONSANAT">Troubleshooting: Anatomy of an
- Action</a> section.</p>
- </div>
-
- <div class="SECT2">
- <h2 class="SECT2"><a name="AF-PATTERNS" id="AF-PATTERNS">8.4.
- Patterns</a></h2>
-
- <p>As mentioned, <span class="APPLICATION">Privoxy</span> uses
- <span class="QUOTE">"patterns"</span> to determine what <span class=
- "emphasis"><i class="EMPHASIS">actions</i></span> might apply to which
- sites and pages your browser attempts to access. These <span class=
- "QUOTE">"patterns"</span> use wild card type <span class=
- "emphasis"><i class="EMPHASIS">pattern</i></span> matching to achieve a
- high degree of flexibility. This allows one expression to be expanded
- and potentially match against many similar patterns.</p>
-
- <p>Generally, an URL pattern has the form <tt class=
- "LITERAL"><host><port>/<path></tt>, where the
- <tt class="LITERAL"><host></tt>, the <tt class=
- "LITERAL"><port></tt> and the <tt class=
- "LITERAL"><path></tt> are optional. (This is why the special
- <tt class="LITERAL">/</tt> pattern matches all URLs). Note that the
- protocol portion of the URL pattern (e.g. <tt class=
- "LITERAL">http://</tt>) should <span class="emphasis"><i class=
- "EMPHASIS">not</i></span> be included in the pattern. This is assumed
- already!</p>
-
- <p>The pattern matching syntax is different for the host and path parts
- of the URL. The host part uses a simple globbing type matching
- technique, while the path part uses more flexible <a href=
- "http://en.wikipedia.org/wiki/Regular_expressions" target=
- "_top"><span class="QUOTE">"Regular Expressions"</span></a> (POSIX
- 1003.2).</p>
-
- <p>The port part of a pattern is a decimal port number preceded by a
- colon (<tt class="LITERAL">:</tt>). If the host part contains a
- numerical IPv6 address, it has to be put into angle brackets
- (<tt class="LITERAL"><</tt>, <tt class="LITERAL">></tt>).</p>
-
- <div class="VARIABLELIST">
- <dl>
- <dt><tt class="LITERAL">www.example.com/</tt></dt>
-
- <dd>
- <p>is a host-only pattern and will match any request to
- <tt class="LITERAL">www.example.com</tt>, regardless of which
- document on that server is requested. So ALL pages in this domain
- would be covered by the scope of this action. Note that a simple
- <tt class="LITERAL">example.com</tt> is different and would NOT
- match.</p>
- </dd>
-
- <dt><tt class="LITERAL">www.example.com</tt></dt>
-
- <dd>
- <p>means exactly the same. For host-only patterns, the trailing
- <tt class="LITERAL">/</tt> may be omitted.</p>
- </dd>
-
- <dt><tt class="LITERAL">www.example.com/index.html</tt></dt>
-
- <dd>
- <p>matches all the documents on <tt class=
- "LITERAL">www.example.com</tt> whose name starts with <tt class=
- "LITERAL">/index.html</tt>.</p>
- </dd>
-
- <dt><tt class="LITERAL">www.example.com/index.html$</tt></dt>
-
- <dd>
- <p>matches only the single document <tt class=
- "LITERAL">/index.html</tt> on <tt class=
- "LITERAL">www.example.com</tt>.</p>
- </dd>
-
- <dt><tt class="LITERAL">/index.html$</tt></dt>
-
- <dd>
- <p>matches the document <tt class="LITERAL">/index.html</tt>,
- regardless of the domain, i.e. on <span class=
- "emphasis"><i class="EMPHASIS">any</i></span> web server
- anywhere.</p>
- </dd>
-
- <dt><tt class="LITERAL">/</tt></dt>
-
- <dd>
- <p>Matches any URL because there's no requirement for either the
- domain or the path to match anything.</p>
- </dd>
-
- <dt><tt class="LITERAL">:8000/</tt></dt>
-
- <dd>
- <p>Matches any URL pointing to TCP port 8000.</p>
- </dd>
-
- <dt><tt class="LITERAL">10.0.0.1/</tt></dt>
-
- <dd>
- <p>Matches any URL with the host address <tt class=
- "LITERAL">10.0.0.1</tt>. (Note that the real URL uses plain
- brackets, not angle brackets.)</p>
- </dd>
-
- <dt><tt class="LITERAL"><2001:db8::1>/</tt></dt>
-
- <dd>
- <p>Matches any URL with the host address <tt class=
- "LITERAL">2001:db8::1</tt>. (Note that the real URL uses plain
- brackets, not angle brackets.)</p>
- </dd>
-
- <dt><tt class="LITERAL">index.html</tt></dt>
-
- <dd>
- <p>matches nothing, since it would be interpreted as a domain
- name and there is no top-level domain called <tt class=
- "LITERAL">.html</tt>. So its a mistake.</p>
- </dd>
- </dl>
- </div>
-
- <div class="SECT3">
- <h3 class="SECT3"><a name="HOST-PATTERN" id="HOST-PATTERN">8.4.1. The
- Host Pattern</a></h3>
-
- <p>The matching of the host part offers some flexible options: if the
- host pattern starts or ends with a dot, it becomes unanchored at that
- end. The host pattern is often referred to as domain pattern as it is
- usually used to match domain names and not IP addresses. For
- example:</p>
-
- <div class="VARIABLELIST">
- <dl>
- <dt><tt class="LITERAL">.example.com</tt></dt>
-
- <dd>
- <p>matches any domain with first-level domain <tt class=
- "LITERAL">com</tt> and second-level domain <tt class=
- "LITERAL">example</tt>. For example <tt class=
- "LITERAL">www.example.com</tt>, <tt class=
- "LITERAL">example.com</tt> and <tt class=
- "LITERAL">foo.bar.baz.example.com</tt>. Note that it wouldn't
- match if the second-level domain was <tt class=
- "LITERAL">another-example</tt>.</p>
- </dd>
-
- <dt><tt class="LITERAL">www.</tt></dt>
-
- <dd>
- <p>matches any domain that <span class="emphasis"><i class=
- "EMPHASIS">STARTS</i></span> with <tt class="LITERAL">www.</tt>
- (It also matches the domain <tt class="LITERAL">www</tt> but
- most of the time that doesn't matter.)</p>
- </dd>
-
- <dt><tt class="LITERAL">.example.</tt></dt>
-
- <dd>
- <p>matches any domain that <span class="emphasis"><i class=
- "EMPHASIS">CONTAINS</i></span> <tt class=
- "LITERAL">.example.</tt>. And, by the way, also included would
- be any files or documents that exist within that domain since
- no path limitations are specified. (Correctly speaking: It
- matches any FQDN that contains <tt class="LITERAL">example</tt>
- as a domain.) This might be <tt class=
- "LITERAL">www.example.com</tt>, <tt class=
- "LITERAL">news.example.de</tt>, or <tt class=
- "LITERAL">www.example.net/cgi/testing.pl</tt> for instance. All
- these cases are matched.</p>
- </dd>
- </dl>
- </div>
-
- <p>Additionally, there are wild-cards that you can use in the domain
- names themselves. These work similarly to shell globbing type
- wild-cards: <span class="QUOTE">"*"</span> represents zero or more
- arbitrary characters (this is equivalent to the <a href=
- "http://en.wikipedia.org/wiki/Regular_expressions" target=
- "_top"><span class="QUOTE">"Regular Expression"</span></a> based
- syntax of <span class="QUOTE">".*"</span>), <span class=
- "QUOTE">"?"</span> represents any single character (this is
- equivalent to the regular expression syntax of a simple <span class=
- "QUOTE">"."</span>), and you can define <span class=
- "QUOTE">"character classes"</span> in square brackets which is
- similar to the same regular expression technique. All of this can be
- freely mixed:</p>
-
- <div class="VARIABLELIST">
- <dl>
- <dt><tt class="LITERAL">ad*.example.com</tt></dt>
-
- <dd>
- <p>matches <span class="QUOTE">"adserver.example.com"</span>,
- <span class="QUOTE">"ads.example.com"</span>, etc but not
- <span class="QUOTE">"sfads.example.com"</span></p>
- </dd>
-
- <dt><tt class="LITERAL">*ad*.example.com</tt></dt>
-
- <dd>
- <p>matches all of the above, and then some.</p>
- </dd>
-
- <dt><tt class="LITERAL">.?pix.com</tt></dt>
-
- <dd>
- <p>matches <tt class="LITERAL">www.ipix.com</tt>, <tt class=
- "LITERAL">pictures.epix.com</tt>, <tt class=
- "LITERAL">a.b.c.d.e.upix.com</tt> etc.</p>
- </dd>
-
- <dt><tt class="LITERAL">www[1-9a-ez].example.c*</tt></dt>
-
- <dd>
- <p>matches <tt class="LITERAL">www1.example.com</tt>,
- <tt class="LITERAL">www4.example.cc</tt>, <tt class=
- "LITERAL">wwwd.example.cy</tt>, <tt class=
- "LITERAL">wwwz.example.com</tt> etc., but <span class=
- "emphasis"><i class="EMPHASIS">not</i></span> <tt class=
- "LITERAL">wwww.example.com</tt>.</p>
- </dd>
- </dl>
- </div>
-
- <p>While flexible, this is not the sophistication of full regular
- expression based syntax.</p>
- </div>
-
- <div class="SECT3">
- <h3 class="SECT3"><a name="PATH-PATTERN" id="PATH-PATTERN">8.4.2. The
- Path Pattern</a></h3>
-
- <p><span class="APPLICATION">Privoxy</span> uses <span class=
- "QUOTE">"modern"</span> POSIX 1003.2 <a href=
- "http://en.wikipedia.org/wiki/Regular_expressions" target=
- "_top"><span class="QUOTE">"Regular Expressions"</span></a> for
- matching the path portion (after the slash), and is thus more
- flexible.</p>
-
- <p>There is an <a href="appendix.html#REGEX">Appendix</a> with a
- brief quick-start into regular expressions, you also might want to
- have a look at your operating system's documentation on regular
- expressions (try <tt class="LITERAL">man re_format</tt>).</p>
-
- <p>Note that the path pattern is automatically left-anchored at the
- <span class="QUOTE">"/"</span>, i.e. it matches as if it would start
- with a <span class="QUOTE">"^"</span> (regular expression speak for
- the beginning of a line).</p>
-
- <p>Please also note that matching in the path is <span class=
- "emphasis"><i class="EMPHASIS">CASE INSENSITIVE</i></span> by
- default, but you can switch to case sensitive at any point in the
- pattern by using the <span class="QUOTE">"(?-i)"</span> switch:
- <tt class="LITERAL">www.example.com/(?-i)PaTtErN.*</tt> will match
- only documents whose path starts with <tt class=
- "LITERAL">PaTtErN</tt> in <span class="emphasis"><i class=
- "EMPHASIS">exactly</i></span> this capitalization.</p>
-
- <div class="VARIABLELIST">
- <dl>
- <dt><tt class="LITERAL">.example.com/.*</tt></dt>
-
- <dd>
- <p>Is equivalent to just <span class=
- "QUOTE">".example.com"</span>, since any documents within that
- domain are matched with or without the <span class=
- "QUOTE">".*"</span> regular expression. This is redundant</p>
- </dd>
-
- <dt><tt class="LITERAL">.example.com/.*/index.html$</tt></dt>
-
- <dd>
- <p>Will match any page in the domain of <span class=
- "QUOTE">"example.com"</span> that is named <span class=
- "QUOTE">"index.html"</span>, and that is part of some path. For
- example, it matches <span class=
- "QUOTE">"www.example.com/testing/index.html"</span> but NOT
- <span class="QUOTE">"www.example.com/index.html"</span> because
- the regular expression called for at least two <span class=
- "QUOTE">"/'s"</span>, thus the path requirement. It also would
- match <span class=
- "QUOTE">"www.example.com/testing/index_html"</span>, because of
- the special meta-character <span class="QUOTE">"."</span>.</p>
- </dd>
-
- <dt><tt class="LITERAL">.example.com/(.*/)?index\.html$</tt></dt>
-
- <dd>
- <p>This regular expression is conditional so it will match any
- page named <span class="QUOTE">"index.html"</span> regardless
- of path which in this case can have one or more <span class=
- "QUOTE">"/'s"</span>. And this one must contain exactly
- <span class="QUOTE">".html"</span> (but does not have to end
- with that!).</p>
- </dd>
-
- <dt><tt class=
- "LITERAL">.example.com/(.*/)(ads|banners?|junk)</tt></dt>
-
- <dd>
- <p>This regular expression will match any path of <span class=
- "QUOTE">"example.com"</span> that contains any of the words
- <span class="QUOTE">"ads"</span>, <span class=
- "QUOTE">"banner"</span>, <span class="QUOTE">"banners"</span>
- (because of the <span class="QUOTE">"?"</span>) or <span class=
- "QUOTE">"junk"</span>. The path does not have to end in these
- words, just contain them.</p>
- </dd>
-
- <dt><tt class=
- "LITERAL">.example.com/(.*/)(ads|banners?|junk)/.*\.(jpe?g|gif|png)$</tt></dt>
-
- <dd>
- <p>This is very much the same as above, except now it must end
- in either <span class="QUOTE">".jpg"</span>, <span class=
- "QUOTE">".jpeg"</span>, <span class="QUOTE">".gif"</span> or
- <span class="QUOTE">".png"</span>. So this one is limited to
- common image formats.</p>
- </dd>
- </dl>
- </div>
-
- <p>There are many, many good examples to be found in <tt class=
- "FILENAME">default.action</tt>, and more tutorials below in <a href=
- "appendix.html#REGEX">Appendix on regular expressions</a>.</p>
- </div>
-
- <div class="SECT3">
- <h3 class="SECT3"><a name="TAG-PATTERN" id="TAG-PATTERN">8.4.3. The
- Request Tag Pattern</a></h3>
-
- <p>Request tag patterns are used to change the applying actions based
- on the request's tags. Tags can be created based on HTTP headers with
- either the <a href=
- "actions-file.html#CLIENT-HEADER-TAGGER">client-header-tagger</a> or
- the <a href=
- "actions-file.html#SERVER-HEADER-TAGGER">server-header-tagger</a>
- action.</p>
-
- <p>Request tag patterns have to start with <span class=
- "QUOTE">"TAG:"</span>, so <span class="APPLICATION">Privoxy</span>
- can tell them apart from other patterns. Everything after the colon
- including white space, is interpreted as a regular expression with
- path pattern syntax, except that tag patterns aren't left-anchored
- automatically (<span class="APPLICATION">Privoxy</span> doesn't
- silently add a <span class="QUOTE">"^"</span>, you have to do it
- yourself if you need it).</p>
-
- <p>To match all requests that are tagged with <span class=
- "QUOTE">"foo"</span> your pattern line should be <span class=
- "QUOTE">"TAG:^foo$"</span>, <span class="QUOTE">"TAG:foo"</span>
- would work as well, but it would also match requests whose tags
- contain <span class="QUOTE">"foo"</span> somewhere. <span class=
- "QUOTE">"TAG: foo"</span> wouldn't work as it requires white
- space.</p>
-
- <p>Sections can contain URL and request tag patterns at the same
- time, but request tag patterns are checked after the URL patterns and
- thus always overrule them, even if they are located before the URL
- patterns.</p>
-
- <p>Once a new request tag is added, Privoxy checks right away if it's
- matched by one of the request tag patterns and updates the action
- settings accordingly. As a result request tags can be used to
- activate other tagger actions, as long as these other taggers look
- for headers that haven't already be parsed.</p>
-
- <p>For example you could tag client requests which use the <tt class=
- "LITERAL">POST</tt> method, then use this tag to activate another
- tagger that adds a tag if cookies are sent, and then use a block
- action based on the cookie tag. This allows the outcome of one
- action, to be input into a subsequent action. However if you'd
- reverse the position of the described taggers, and activated the
- method tagger based on the cookie tagger, no method tags would be
- created. The method tagger would look for the request line, but at
- the time the cookie tag is created, the request line has already been
- parsed.</p>
-
- <p>While this is a limitation you should be aware of, this kind of
- indirection is seldom needed anyway and even the example doesn't make
- too much sense.</p>
- </div>
-
- <div class="SECT3">
- <h3 class="SECT3"><a name="NEGATIVE-TAG-PATTERNS" id=
- "NEGATIVE-TAG-PATTERNS">8.4.4. The Negative Request Tag
- Patterns</a></h3>
-
- <p>To match requests that do not have a certain request tag, specify
- a negative tag pattern by prefixing the tag pattern line with either
- <span class="QUOTE">"NO-REQUEST-TAG:"</span> or <span class=
- "QUOTE">"NO-RESPONSE-TAG:"</span> instead of <span class=
- "QUOTE">"TAG:"</span>.</p>
-
- <p>Negative request tag patterns created with <span class=
- "QUOTE">"NO-REQUEST-TAG:"</span> are checked after all client headers
- are scanned, the ones created with <span class=
- "QUOTE">"NO-RESPONSE-TAG:"</span> are checked after all server
- headers are scanned. In both cases all the created tags are
- considered.</p>
- </div>
-
- <div class="SECT3">
- <h3 class="SECT3"><a name="CLIENT-TAG-PATTERN" id=
- "CLIENT-TAG-PATTERN">8.4.5. The Client Tag Pattern</a></h3>
-
- <div class="WARNING">
- <table class="WARNING" border="1" width="100%">
- <tr>
- <td align="center"><b>Warning</b></td>
- </tr>
-
- <tr>
- <td align="left">
- <p>This is an experimental feature. The syntax is likely to
- change in future versions.</p>
- </td>
- </tr>
- </table>
- </div>
-
- <p>Client tag patterns are not set based on HTTP headers but based on
- the client's IP address. Users can enable them themselves, but the
- Privoxy admin controls which tags are available and what their effect
- is.</p>
-
- <p>After a client-specific tag has been defined with the <a href=
- "config.html#CLIENT-SPECIFIC-TAG">client-specific-tag</a>, directive,
- action sections can be activated based on the tag by using a
- CLIENT-TAG pattern. The CLIENT-TAG pattern is evaluated at the same
- priority as URL patterns, as a result the last matching pattern wins.
- Tags that are created based on client or server headers are evaluated
- later on and can overrule CLIENT-TAG and URL patterns!</p>
-
- <p>The tag is set for all requests that come from clients that
- requested it to be set. Note that "clients" are differentiated by IP
- address, if the IP address changes the tag has to be requested
- again.</p>
-
- <p>Clients can request tags to be set by using the CGI interface
- <a href="http://config.privoxy.org/client-tags" target=
- "_top">http://config.privoxy.org/client-tags</a>.</p>
-
- <p>Example:</p>
-
- <table border="0" bgcolor="#E0E0E0" width="100%">
- <tr>
- <td>
- <pre class="SCREEN">
-# If the admin defined the client-specific-tag circumvent-blocks,
-# and the request comes from a client that previously requested
-# the tag to be set, overrule all previous +block actions that
-# are enabled based on URL to CLIENT-TAG patterns.
-{-block}
-CLIENT-TAG:^circumvent-blocks$
-
-# This section is not overruled because it's located after
-# the previous one.
-{+block{Nobody is supposed to request this.}}
-example.org/blocked-example-page
-</pre>
- </td>
- </tr>
- </table>
- </div>
- </div>
-
- <div class="SECT2">
- <h2 class="SECT2"><a name="ACTIONS" id="ACTIONS">8.5. Actions</a></h2>
-
- <p>All actions are disabled by default, until they are explicitly
- enabled somewhere in an actions file. Actions are turned on if preceded
- with a <span class="QUOTE">"+"</span>, and turned off if preceded with
- a <span class="QUOTE">"-"</span>. So a <tt class="LITERAL">+action</tt>
- means <span class="QUOTE">"do that action"</span>, e.g. <tt class=
- "LITERAL">+block</tt> means <span class="QUOTE">"please block URLs that
- match the following patterns"</span>, and <tt class=
- "LITERAL">-block</tt> means <span class="QUOTE">"don't block URLs that
- match the following patterns, even if <tt class="LITERAL">+block</tt>
- previously applied."</span></p>
-
- <p>Again, actions are invoked by placing them on a line, enclosed in
- curly braces and separated by whitespace, like in <tt class=
- "LITERAL">{+some-action -some-other-action{some-parameter}}</tt>,
- followed by a list of URL patterns, one per line, to which they apply.
- Together, the actions line and the following pattern lines make up a
- section of the actions file.</p>
-
- <p>Actions fall into three categories:</p>
-
- <ul>
- <li>
- <p>Boolean, i.e the action can only be <span class=
- "QUOTE">"enabled"</span> or <span class="QUOTE">"disabled"</span>.
- Syntax:</p>
-
- <table border="0" bgcolor="#E0E0E0" width="90%">
- <tr>
- <td>
- <pre class="SCREEN">
- +<tt class="REPLACEABLE"><i>name</i></tt> # enable action <tt class=
-"REPLACEABLE"><i>name</i></tt>
- -<tt class=
-"REPLACEABLE"><i>name</i></tt> # disable action <tt class="REPLACEABLE"><i>name</i></tt>
-</pre>
- </td>
- </tr>
- </table>
-
- <p>Example: <tt class="LITERAL">+handle-as-image</tt></p>
- </li>
-
- <li>
- <p>Parameterized, where some value is required in order to enable
- this type of action. Syntax:</p>
-
- <table border="0" bgcolor="#E0E0E0" width="90%">
- <tr>
- <td>
- <pre class="SCREEN">
- +<tt class="REPLACEABLE"><i>name</i></tt>{<tt class=
-"REPLACEABLE"><i>param</i></tt>} # enable action and set parameter to <tt class="REPLACEABLE"><i>param</i></tt>,
- # overwriting parameter from previous match if necessary
- -<tt class=
-"REPLACEABLE"><i>name</i></tt> # disable action. The parameter can be omitted
-</pre>
- </td>
- </tr>
- </table>
-
- <p>Note that if the URL matches multiple positive forms of a
- parameterized action, the last match wins, i.e. the params from
- earlier matches are simply ignored.</p>
-
- <p>Example: <tt class="LITERAL">+hide-user-agent{Mozilla/5.0 (X11;
- U; FreeBSD i386; en-US; rv:1.8.1.4) Gecko/20070602
- Firefox/2.0.0.4}</tt></p>
- </li>
-
- <li>
- <p>Multi-value. These look exactly like parameterized actions, but
- they behave differently: If the action applies multiple times to
- the same URL, but with different parameters, <span class=
- "emphasis"><i class="EMPHASIS">all</i></span> the parameters from
- <span class="emphasis"><i class="EMPHASIS">all</i></span> matches
- are remembered. This is used for actions that can be executed for
- the same request repeatedly, like adding multiple headers, or
- filtering through multiple filters. Syntax:</p>
-
- <table border="0" bgcolor="#E0E0E0" width="90%">
- <tr>
- <td>
- <pre class="SCREEN">
- +<tt class="REPLACEABLE"><i>name</i></tt>{<tt class=
-"REPLACEABLE"><i>param</i></tt>} # enable action and add <tt class=
-"REPLACEABLE"><i>param</i></tt> to the list of parameters
- -<tt class="REPLACEABLE"><i>name</i></tt>{<tt class=
-"REPLACEABLE"><i>param</i></tt>} # remove the parameter <tt class=
-"REPLACEABLE"><i>param</i></tt> from the list of parameters
- # If it was the last one left, disable the action.
- <tt class=
-"REPLACEABLE"><i>-name</i></tt> # disable this action completely and remove all parameters from the list
-</pre>
- </td>
- </tr>
- </table>
-
- <p>Examples: <tt class="LITERAL">+add-header{X-Fun-Header: Some
- text}</tt> and <tt class=
- "LITERAL">+filter{html-annoyances}</tt></p>
- </li>
- </ul>
-
- <p>If nothing is specified in any actions file, no <span class=
- "QUOTE">"actions"</span> are taken. So in this case <span class=
- "APPLICATION">Privoxy</span> would just be a normal, non-blocking,
- non-filtering proxy. You must specifically enable the privacy and
- blocking features you need (although the provided default actions files
- will give a good starting point).</p>
-
- <p>Later defined action sections always over-ride earlier ones of the
- same type. So exceptions to any rules you make, should come in the
- latter part of the file (or in a file that is processed later when
- using multiple actions files such as <tt class=
- "FILENAME">user.action</tt>). For multi-valued actions, the actions are
- applied in the order they are specified. Actions files are processed in
- the order they are defined in <tt class="FILENAME">config</tt> (the
- default installation has three actions files). It also quite possible
- for any given URL to match more than one <span class=
- "QUOTE">"pattern"</span> (because of wildcards and regular
- expressions), and thus to trigger more than one set of actions! Last
- match wins.</p>
-
- <p>The list of valid <span class="APPLICATION">Privoxy</span> actions
- are:</p>
-
- <div class="SECT3">
- <h4 class="SECT3"><a name="ADD-HEADER" id="ADD-HEADER">8.5.1.
- add-header</a></h4>
-
- <div class="VARIABLELIST">
- <dl>
- <dt>Typical use:</dt>
-
- <dd>
- <p>Confuse log analysis, custom applications</p>
- </dd>
-
- <dt>Effect:</dt>
-
- <dd>
- <p>Sends a user defined HTTP header to the web server.</p>
- </dd>
-
- <dt>Type:</dt>
-
- <dd>
- <p>Multi-value.</p>
- </dd>
-
- <dt>Parameter:</dt>
-
- <dd>
- <p>Any string value is possible. Validity of the defined HTTP
- headers is not checked. It is recommended that you use the
- <span class="QUOTE">"<tt class="LITERAL">X-</tt>"</span> prefix
- for custom headers.</p>
- </dd>
-
- <dt>Notes:</dt>
-
- <dd>
- <p>This action may be specified multiple times, in order to
- define multiple headers. This is rarely needed for the typical
- user. If you don't know what <span class="QUOTE">"HTTP
- headers"</span> are, you definitely don't need to worry about
- this one.</p>
-
- <p>Headers added by this action are not modified by other
- actions.</p>
- </dd>
-
- <dt>Example usage:</dt>
-
- <dd>
- <table border="0" bgcolor="#E0E0E0" width="90%">
- <tr>
- <td>
- <pre class="SCREEN">
-# Add a DNT ("Do not track") header to all requests,
-# event to those that already have one.
-#
-# This is just an example, not a recommendation.
-#
-# There is no reason to believe that user-tracking websites care
-# about the DNT header and depending on the User-Agent, adding the
-# header may make user-tracking easier.
-{+add-header{DNT: 1}}
-/
-</pre>
- </td>
- </tr>
- </table>
- </dd>
- </dl>
- </div>
- </div>
-
- <div class="SECT3">
- <h4 class="SECT3"><a name="BLOCK" id="BLOCK">8.5.2. block</a></h4>
-
- <div class="VARIABLELIST">
- <dl>
- <dt>Typical use:</dt>
-
- <dd>
- <p>Block ads or other unwanted content</p>
- </dd>
-
- <dt>Effect:</dt>
-
- <dd>
- <p>Requests for URLs to which this action applies are blocked,
- i.e. the requests are trapped by <span class=
- "APPLICATION">Privoxy</span> and the requested URL is never
- retrieved, but is answered locally with a substitute page or
- image, as determined by the <tt class="LITERAL"><a href=
- "actions-file.html#HANDLE-AS-IMAGE">handle-as-image</a></tt>,
- <tt class="LITERAL"><a href=
- "actions-file.html#SET-IMAGE-BLOCKER">set-image-blocker</a></tt>,
- and <tt class="LITERAL"><a href=
- "actions-file.html#HANDLE-AS-EMPTY-DOCUMENT">handle-as-empty-document</a></tt>
- actions.</p>
- </dd>
-
- <dt>Type:</dt>
-
- <dd>
- <p>Parameterized.</p>
- </dd>
-
- <dt>Parameter:</dt>
-
- <dd>
- <p>A block reason that should be given to the user.</p>
- </dd>
-
- <dt>Notes:</dt>
-
- <dd>
- <p><span class="APPLICATION">Privoxy</span> sends a special
- <span class="QUOTE">"BLOCKED"</span> page for requests to
- blocked pages. This page contains the block reason given as
- parameter, a link to find out why the block action applies, and
- a click-through to the blocked content (the latter only if the
- force feature is available and enabled).</p>
-
- <p>A very important exception occurs if <span class=
- "emphasis"><i class="EMPHASIS">both</i></span> <tt class=
- "LITERAL">block</tt> and <tt class="LITERAL"><a href=
- "actions-file.html#HANDLE-AS-IMAGE">handle-as-image</a></tt>,
- apply to the same request: it will then be replaced by an
- image. If <tt class="LITERAL"><a href=
- "actions-file.html#SET-IMAGE-BLOCKER">set-image-blocker</a></tt>
- (see below) also applies, the type of image will be determined
- by its parameter, if not, the standard checkerboard pattern is
- sent.</p>
-
- <p>It is important to understand this process, in order to
- understand how <span class="APPLICATION">Privoxy</span> deals
- with ads and other unwanted content. Blocking is a core
- feature, and one upon which various other features depend.</p>
-
- <p>The <tt class="LITERAL"><a href=
- "actions-file.html#FILTER">filter</a></tt> action can perform a
- very similar task, by <span class="QUOTE">"blocking"</span>
- 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.</p>
- </dd>
-
- <dt>Example usage (section):</dt>
-
- <dd>
- <table border="0" bgcolor="#E0E0E0" width="90%">
- <tr>
- <td>
- <pre class="SCREEN">
-{+block{No nasty stuff for you.}}
-# Block and replace with "blocked" page
- .nasty-stuff.example.com
-
-{+block{Doubleclick banners.} +handle-as-image}
-# Block and replace with image
- .ad.doubleclick.net
- .ads.r.us/banners/
-
-{+block{Layered ads.} +handle-as-empty-document}
-# Block and then ignore
- adserver.example.net/.*\.js$
-</pre>
- </td>
- </tr>
- </table>
- </dd>
- </dl>
- </div>
- </div>
-
- <div class="SECT3">
- <h4 class="SECT3"><a name="CHANGE-X-FORWARDED-FOR" id=
- "CHANGE-X-FORWARDED-FOR">8.5.3. change-x-forwarded-for</a></h4>
-
- <div class="VARIABLELIST">
- <dl>
- <dt>Typical use:</dt>
-
- <dd>
- <p>Improve privacy by not forwarding the source of the request
- in the HTTP headers.</p>
- </dd>
-
- <dt>Effect:</dt>
-
- <dd>
- <p>Deletes the <span class="QUOTE">"X-Forwarded-For:"</span>
- HTTP header from the client request, or adds a new one.</p>
- </dd>
-
- <dt>Type:</dt>
-
- <dd>
- <p>Parameterized.</p>
- </dd>
-
- <dt>Parameter:</dt>
-
- <dd>
- <ul>
- <li>
- <p><span class="QUOTE">"block"</span> to delete the
- header.</p>
- </li>
-
- <li>
- <p><span class="QUOTE">"add"</span> to create the header
- (or append the client's IP address to an already existing
- one).</p>
- </li>
- </ul>
- </dd>
-
- <dt>Notes:</dt>
-
- <dd>
- <p>It is safe and recommended to use <tt class=
- "LITERAL">block</tt>.</p>
-
- <p>Forwarding the source address of the request may make sense
- in some multi-user setups but is also a privacy risk.</p>
- </dd>
-
- <dt>Example usage:</dt>
-
- <dd>
- <table border="0" bgcolor="#E0E0E0" width="90%">
- <tr>
- <td>
- <pre class="SCREEN">
-+change-x-forwarded-for{block}
-</pre>
- </td>
- </tr>
- </table>
- </dd>
- </dl>
- </div>
- </div>
-
- <div class="SECT3">
- <h4 class="SECT3"><a name="CLIENT-HEADER-FILTER" id=
- "CLIENT-HEADER-FILTER">8.5.4. client-header-filter</a></h4>
-
- <div class="VARIABLELIST">
- <dl>
- <dt>Typical use:</dt>
-
- <dd>
- <p>Rewrite or remove single client headers.</p>
- </dd>
-
- <dt>Effect:</dt>
-
- <dd>
- <p>All client headers to which this action applies are filtered
- on-the-fly through the specified regular expression based
- substitutions.</p>
- </dd>
-
- <dt>Type:</dt>
-
- <dd>
- <p>Multi-value.</p>
- </dd>
-
- <dt>Parameter:</dt>
-
- <dd>
- <p>The name of a client-header filter, as defined in one of the
- <a href="filter-file.html">filter files</a>.</p>
- </dd>
-
- <dt>Notes:</dt>
-
- <dd>
- <p>Client-header filters are applied to each header on its own,
- not to all at once. This makes it easier to diagnose problems,
- but on the downside you can't write filters that only change
- header x if header y's value is z. You can do that by using
- tags though.</p>
-
- <p>Client-header filters are executed after the other header
- actions have finished and use their output as input.</p>
-
- <p>If the request URI gets changed, <span class=
- "APPLICATION">Privoxy</span> will detect that and use the new
- one. This can be used to rewrite the request destination behind
- the client's back, for example to specify a Tor exit relay for
- certain requests.</p>
-
- <p>Please refer to the <a href="filter-file.html">filter file
- chapter</a> to learn which client-header filters are available
- by default, and how to create your own.</p>
- </dd>
-
- <dt>Example usage (section):</dt>
-
- <dd>
- <table border="0" bgcolor="#E0E0E0" width="90%">
- <tr>
- <td>
- <pre class="SCREEN">
-# Hide Tor exit notation in Host and Referer Headers
-{+client-header-filter{hide-tor-exit-notation}}
-/
-
-</pre>
- </td>
- </tr>
- </table>
- </dd>
- </dl>
- </div>
- </div>
-
- <div class="SECT3">
- <h4 class="SECT3"><a name="CLIENT-HEADER-TAGGER" id=
- "CLIENT-HEADER-TAGGER">8.5.5. client-header-tagger</a></h4>
-
- <div class="VARIABLELIST">
- <dl>
- <dt>Typical use:</dt>
-
- <dd>
- <p>Block requests based on their headers.</p>
- </dd>
-
- <dt>Effect:</dt>
-
- <dd>
- <p>Client headers to which this action applies are filtered
- on-the-fly through the specified regular expression based
- substitutions, the result is used as tag.</p>
- </dd>
-
- <dt>Type:</dt>
-
- <dd>
- <p>Multi-value.</p>
- </dd>
-
- <dt>Parameter:</dt>
-
- <dd>
- <p>The name of a client-header tagger, as defined in one of the
- <a href="filter-file.html">filter files</a>.</p>
- </dd>
-
- <dt>Notes:</dt>
-
- <dd>
- <p>Client-header taggers are applied to each header on its own,
- and as the header isn't modified, each tagger <span class=
- "QUOTE">"sees"</span> the original.</p>
-
- <p>Client-header taggers are the first actions that are
- executed and their tags can be used to control every other
- action.</p>
- </dd>
-
- <dt>Example usage (section):</dt>
-
- <dd>
- <table border="0" bgcolor="#E0E0E0" width="90%">
- <tr>
- <td>
- <pre class="SCREEN">
-# Tag every request with the User-Agent header
-{+client-header-tagger{user-agent}}
-/
-
-# Tagging itself doesn't change the action
-# settings, sections with TAG patterns do:
-#
-# If it's a download agent, use a different forwarding proxy,
-# show the real User-Agent and make sure resume works.
-{+forward-override{forward-socks5 10.0.0.2:2222 .} \
- -hide-if-modified-since \
- -overwrite-last-modified \
- -hide-user-agent \
- -filter \
- -deanimate-gifs \
-}
-TAG:^User-Agent: NetBSD-ftp/
-TAG:^User-Agent: Novell ZYPP Installer
-TAG:^User-Agent: RPM APT-HTTP/
-TAG:^User-Agent: fetch libfetch/
-TAG:^User-Agent: Ubuntu APT-HTTP/
-TAG:^User-Agent: MPlayer/
-
-</pre>
- </td>
- </tr>
- </table>
-
- <table border="0" bgcolor="#E0E0E0" width="90%">
- <tr>
- <td>
- <pre class="SCREEN">
-# Tag all requests with the Range header set
-{+client-header-tagger{range-requests}}
-/
-
-# Disable filtering for the tagged requests.
-#
-# With filtering enabled Privoxy would remove the Range headers
-# to be able to filter the whole response. The downside is that
-# it prevents clients from resuming downloads or skipping over
-# parts of multimedia files.
-{-filter -deanimate-gifs}
-TAG:^RANGE-REQUEST$
-
-</pre>
- </td>
- </tr>
- </table>
- </dd>
- </dl>
- </div>
- </div>
-
- <div class="SECT3">
- <h4 class="SECT3"><a name="CONTENT-TYPE-OVERWRITE" id=
- "CONTENT-TYPE-OVERWRITE">8.5.6. content-type-overwrite</a></h4>
-
- <div class="VARIABLELIST">
- <dl>
- <dt>Typical use:</dt>
-
- <dd>
- <p>Stop useless download menus from popping up, or change the
- browser's rendering mode</p>
- </dd>
-
- <dt>Effect:</dt>
-
- <dd>
- <p>Replaces the <span class="QUOTE">"Content-Type:"</span> HTTP
- server header.</p>
- </dd>
-
- <dt>Type:</dt>
-
- <dd>
- <p>Parameterized.</p>
- </dd>
-
- <dt>Parameter:</dt>
-
- <dd>
- <p>Any string.</p>
- </dd>
-
- <dt>Notes:</dt>
-
- <dd>
- <p>The <span class="QUOTE">"Content-Type:"</span> HTTP server
- header is used by the browser to decide what to do with the
- document. The value of this header can cause the browser to
- open a download menu instead of displaying the document by
- itself, even if the document's format is supported by the
- browser.</p>
-
- <p>The declared content type can also affect which rendering
- mode the browser chooses. If XHTML is delivered as <span class=
- "QUOTE">"text/html"</span>, many browsers treat it as yet
- another broken HTML document. If it is send as <span class=
- "QUOTE">"application/xml"</span>, browsers with XHTML support
- will only display it, if the syntax is correct.</p>
-
- <p>If you see a web site that proudly uses XHTML buttons, but
- sets <span class="QUOTE">"Content-Type: text/html"</span>, you
- can use <span class="APPLICATION">Privoxy</span> to overwrite
- it with <span class="QUOTE">"application/xml"</span> and
- validate the web master's claim inside your XHTML-supporting
- browser. If the syntax is incorrect, the browser will complain
- loudly.</p>
-
- <p>You can also go the opposite direction: if your browser
- prints error messages instead of rendering a document falsely
- declared as XHTML, you can overwrite the content type with
- <span class="QUOTE">"text/html"</span> and have it rendered as
- broken HTML document.</p>
-
- <p>By default <tt class="LITERAL">content-type-overwrite</tt>
- only replaces <span class="QUOTE">"Content-Type:"</span>
- headers that look like some kind of text. If you want to
- overwrite it unconditionally, you have to combine it with
- <tt class="LITERAL"><a href=
- "actions-file.html#FORCE-TEXT-MODE">force-text-mode</a></tt>.
- This limitation exists for a reason, think twice before
- circumventing it.</p>
-
- <p>Most of the time it's easier to replace this action with a
- custom <tt class="LITERAL"><a href=
- "actions-file.html#SERVER-HEADER-FILTER">server-header
- filter</a></tt>. It allows you to activate it for every
- document of a certain site and it will still only replace the
- content types you aimed at.</p>
-
- <p>Of course you can apply <tt class=
- "LITERAL">content-type-overwrite</tt> to a whole site and then
- make URL based exceptions, but it's a lot more work to get the
- same precision.</p>
- </dd>
-
- <dt>Example usage (sections):</dt>
-
- <dd>
- <table border="0" bgcolor="#E0E0E0" width="90%">
- <tr>
- <td>
- <pre class="SCREEN">
-# Check if www.example.net/ really uses valid XHTML
-{ +content-type-overwrite{application/xml} }
-www.example.net/
-
-# but leave the content type unmodified if the URL looks like a style sheet
-{-content-type-overwrite}
-www.example.net/.*\.css$
-www.example.net/.*style
-</pre>
- </td>
- </tr>
- </table>
- </dd>
- </dl>
- </div>
- </div>
-
- <div class="SECT3">
- <h4 class="SECT3"><a name="CRUNCH-CLIENT-HEADER" id=
- "CRUNCH-CLIENT-HEADER">8.5.7. crunch-client-header</a></h4>
-
- <div class="VARIABLELIST">
- <dl>
- <dt>Typical use:</dt>
-
- <dd>
- <p>Remove a client header <span class=
- "APPLICATION">Privoxy</span> has no dedicated action for.</p>
- </dd>
-
- <dt>Effect:</dt>
-
- <dd>
- <p>Deletes every header sent by the client that contains the
- string the user supplied as parameter.</p>
- </dd>
-
- <dt>Type:</dt>
-
- <dd>
- <p>Parameterized.</p>
- </dd>
-
- <dt>Parameter:</dt>
-
- <dd>
- <p>Any string.</p>
- </dd>
-
- <dt>Notes:</dt>
-
- <dd>
- <p>This action allows you to block client headers for which no
- dedicated <span class="APPLICATION">Privoxy</span> action
- exists. <span class="APPLICATION">Privoxy</span> will remove
- every client header that contains the string you supplied as
- parameter.</p>
-
- <p>Regular expressions are <span class="emphasis"><i class=
- "EMPHASIS">not supported</i></span> and you can't use this
- action to block different headers in the same request, unless
- they contain the same string.</p>
-
- <p><tt class="LITERAL">crunch-client-header</tt> is only meant
- for quick tests. If you have to block several different
- headers, or only want to modify parts of them, you should use a
- <tt class="LITERAL"><a href=
- "actions-file.html#CLIENT-HEADER-FILTER">client-header
- filter</a></tt>.</p>
-
- <div class="WARNING">
- <table class="WARNING" border="1" width="90%">
- <tr>
- <td align="center"><b>Warning</b></td>
- </tr>
-
- <tr>
- <td align="left">
- <p>Don't block any header without understanding the
- consequences.</p>
- </td>
- </tr>
- </table>
- </div>
- </dd>
-
- <dt>Example usage (section):</dt>
-
- <dd>
- <table border="0" bgcolor="#E0E0E0" width="90%">
- <tr>
- <td>
- <pre class="SCREEN">
-# Block the non-existent "Privacy-Violation:" client header
-{ +crunch-client-header{Privacy-Violation:} }
-/
-
-</pre>
- </td>
- </tr>
- </table>
- </dd>
- </dl>
- </div>
- </div>
-
- <div class="SECT3">
- <h4 class="SECT3"><a name="CRUNCH-IF-NONE-MATCH" id=
- "CRUNCH-IF-NONE-MATCH">8.5.8. crunch-if-none-match</a></h4>
-
- <div class="VARIABLELIST">
- <dl>
- <dt>Typical use:</dt>
-
- <dd>
- <p>Prevent yet another way to track the user's steps between
- sessions.</p>
- </dd>
-
- <dt>Effect:</dt>
-
- <dd>
- <p>Deletes the <span class="QUOTE">"If-None-Match:"</span> HTTP
- client header.</p>
- </dd>
-
- <dt>Type:</dt>
-
- <dd>
- <p>Boolean.</p>
- </dd>
-
- <dt>Parameter:</dt>
-
- <dd>
- <p>N/A</p>
- </dd>
-
- <dt>Notes:</dt>
-
- <dd>
- <p>Removing the <span class="QUOTE">"If-None-Match:"</span>
- HTTP client header is useful for filter testing, where you want
- to force a real reload instead of getting status code
- <span class="QUOTE">"304"</span> which would cause the browser
- to use a cached copy of the page.</p>
-
- <p>It is also useful to make sure the header isn't used as a
- cookie replacement (unlikely but possible).</p>
-
- <p>Blocking the <span class="QUOTE">"If-None-Match:"</span>
- header shouldn't cause any caching problems, as long as the
- <span class="QUOTE">"If-Modified-Since:"</span> header isn't
- blocked or missing as well.</p>
-
- <p>It is recommended to use this action together with
- <tt class="LITERAL"><a href=
- "actions-file.html#HIDE-IF-MODIFIED-SINCE">hide-if-modified-since</a></tt>
- and <tt class="LITERAL"><a href=
- "actions-file.html#OVERWRITE-LAST-MODIFIED">overwrite-last-modified</a></tt>.</p>
- </dd>
-
- <dt>Example usage (section):</dt>
-
- <dd>
- <table border="0" bgcolor="#E0E0E0" width="90%">
- <tr>
- <td>
- <pre class="SCREEN">
-# Let the browser revalidate cached documents but don't
-# allow the server to use the revalidation headers for user tracking.
-{+hide-if-modified-since{-60} \
- +overwrite-last-modified{randomize} \
- +crunch-if-none-match}
-/
-</pre>
- </td>
- </tr>
- </table>
- </dd>
- </dl>
- </div>
- </div>
-
- <div class="SECT3">
- <h4 class="SECT3"><a name="CRUNCH-INCOMING-COOKIES" id=
- "CRUNCH-INCOMING-COOKIES">8.5.9. crunch-incoming-cookies</a></h4>
-
- <div class="VARIABLELIST">
- <dl>
- <dt>Typical use:</dt>
-
- <dd>
- <p>Prevent the web server from setting HTTP cookies on your
- system</p>
- </dd>
-
- <dt>Effect:</dt>
-
- <dd>
- <p>Deletes any <span class="QUOTE">"Set-Cookie:"</span> HTTP
- headers from server replies.</p>
- </dd>
-
- <dt>Type:</dt>
-
- <dd>
- <p>Boolean.</p>
- </dd>
-
- <dt>Parameter:</dt>
-
- <dd>
- <p>N/A</p>
- </dd>
-
- <dt>Notes:</dt>
-
- <dd>
- <p>This action is only concerned with <span class=
- "emphasis"><i class="EMPHASIS">incoming</i></span> HTTP
- cookies. For <span class="emphasis"><i class=
- "EMPHASIS">outgoing</i></span> HTTP cookies, use <tt class=
- "LITERAL"><a href=
- "actions-file.html#CRUNCH-OUTGOING-COOKIES">crunch-outgoing-cookies</a></tt>.
- Use <span class="emphasis"><i class="EMPHASIS">both</i></span>
- to disable HTTP cookies completely.</p>
-
- <p>It makes <span class="emphasis"><i class="EMPHASIS">no sense
- at all</i></span> to use this action in conjunction with the
- <tt class="LITERAL"><a href=
- "actions-file.html#SESSION-COOKIES-ONLY">session-cookies-only</a></tt>
- action, since it would prevent the session cookies from being
- set. See also <tt class="LITERAL"><a href=
- "actions-file.html#FILTER-CONTENT-COOKIES">filter-content-cookies</a></tt>.</p>
- </dd>
-
- <dt>Example usage:</dt>
-
- <dd>
- <table border="0" bgcolor="#E0E0E0" width="90%">
- <tr>
- <td>
- <pre class="SCREEN">
-+crunch-incoming-cookies
-</pre>
- </td>
- </tr>
- </table>
- </dd>
- </dl>
- </div>
- </div>
-
- <div class="SECT3">
- <h4 class="SECT3"><a name="CRUNCH-SERVER-HEADER" id=
- "CRUNCH-SERVER-HEADER">8.5.10. crunch-server-header</a></h4>
-
- <div class="VARIABLELIST">
- <dl>
- <dt>Typical use:</dt>
-
- <dd>
- <p>Remove a server header <span class=
- "APPLICATION">Privoxy</span> has no dedicated action for.</p>
- </dd>
-
- <dt>Effect:</dt>
-
- <dd>
- <p>Deletes every header sent by the server that contains the
- string the user supplied as parameter.</p>
- </dd>
-
- <dt>Type:</dt>
-
- <dd>
- <p>Parameterized.</p>
- </dd>
-
- <dt>Parameter:</dt>
-
- <dd>
- <p>Any string.</p>
- </dd>
-
- <dt>Notes:</dt>
-
- <dd>
- <p>This action allows you to block server headers for which no
- dedicated <span class="APPLICATION">Privoxy</span> action
- exists. <span class="APPLICATION">Privoxy</span> will remove
- every server header that contains the string you supplied as
- parameter.</p>
-
- <p>Regular expressions are <span class="emphasis"><i class=
- "EMPHASIS">not supported</i></span> and you can't use this
- action to block different headers in the same request, unless
- they contain the same string.</p>
-
- <p><tt class="LITERAL">crunch-server-header</tt> is only meant
- for quick tests. If you have to block several different
- headers, or only want to modify parts of them, you should use a
- custom <tt class="LITERAL"><a href=
- "actions-file.html#SERVER-HEADER-FILTER">server-header
- filter</a></tt>.</p>
-
- <div class="WARNING">
- <table class="WARNING" border="1" width="90%">
- <tr>
- <td align="center"><b>Warning</b></td>
- </tr>
-
- <tr>
- <td align="left">
- <p>Don't block any header without understanding the
- consequences.</p>
- </td>
- </tr>
- </table>
- </div>
- </dd>
-
- <dt>Example usage (section):</dt>
-
- <dd>
- <table border="0" bgcolor="#E0E0E0" width="90%">
- <tr>
- <td>
- <pre class="SCREEN">
-# Crunch server headers that try to prevent caching
-{ +crunch-server-header{no-cache} }
-/
-</pre>
- </td>
- </tr>
- </table>
- </dd>
- </dl>
- </div>
- </div>
-
- <div class="SECT3">
- <h4 class="SECT3"><a name="CRUNCH-OUTGOING-COOKIES" id=
- "CRUNCH-OUTGOING-COOKIES">8.5.11. crunch-outgoing-cookies</a></h4>
-
- <div class="VARIABLELIST">
- <dl>
- <dt>Typical use:</dt>
-
- <dd>
- <p>Prevent the web server from reading any HTTP cookies from
- your system</p>
- </dd>
-
- <dt>Effect:</dt>
-
- <dd>
- <p>Deletes any <span class="QUOTE">"Cookie:"</span> HTTP
- headers from client requests.</p>
- </dd>
-
- <dt>Type:</dt>
-
- <dd>
- <p>Boolean.</p>
- </dd>
-
- <dt>Parameter:</dt>
-
- <dd>
- <p>N/A</p>
- </dd>
-
- <dt>Notes:</dt>
-
- <dd>
- <p>This action is only concerned with <span class=
- "emphasis"><i class="EMPHASIS">outgoing</i></span> HTTP
- cookies. For <span class="emphasis"><i class=
- "EMPHASIS">incoming</i></span> HTTP cookies, use <tt class=
- "LITERAL"><a href=
- "actions-file.html#CRUNCH-INCOMING-COOKIES">crunch-incoming-cookies</a></tt>.
- Use <span class="emphasis"><i class="EMPHASIS">both</i></span>
- to disable HTTP cookies completely.</p>
-
- <p>It makes <span class="emphasis"><i class="EMPHASIS">no sense
- at all</i></span> to use this action in conjunction with the
- <tt class="LITERAL"><a href=
- "actions-file.html#SESSION-COOKIES-ONLY">session-cookies-only</a></tt>
- action, since it would prevent the session cookies from being
- read.</p>
- </dd>
-
- <dt>Example usage:</dt>
-
- <dd>
- <table border="0" bgcolor="#E0E0E0" width="90%">
- <tr>
- <td>
- <pre class="SCREEN">
-+crunch-outgoing-cookies
-</pre>
- </td>
- </tr>
- </table>
- </dd>
- </dl>
- </div>
- </div>
-
- <div class="SECT3">
- <h4 class="SECT3"><a name="DEANIMATE-GIFS" id=
- "DEANIMATE-GIFS">8.5.12. deanimate-gifs</a></h4>
-
- <div class="VARIABLELIST">
- <dl>
- <dt>Typical use:</dt>
-
- <dd>
- <p>Stop those annoying, distracting animated GIF images.</p>
- </dd>
-
- <dt>Effect:</dt>
-
- <dd>
- <p>De-animate GIF animations, i.e. reduce them to their first
- or last image.</p>
- </dd>
-
- <dt>Type:</dt>
-
- <dd>
- <p>Parameterized.</p>
- </dd>
-
- <dt>Parameter:</dt>
-
- <dd>
- <p><span class="QUOTE">"last"</span> or <span class=
- "QUOTE">"first"</span></p>
- </dd>
-
- <dt>Notes:</dt>
-
- <dd>
- <p>This will also shrink the images considerably (in bytes, not
- pixels!). If the option <span class="QUOTE">"first"</span> is
- given, the first frame of the animation is used as the
- replacement. If <span class="QUOTE">"last"</span> 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).</p>
-
- <p>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.</p>
- </dd>
-
- <dt>Example usage:</dt>
-
- <dd>
- <table border="0" bgcolor="#E0E0E0" width="90%">
- <tr>
- <td>
- <pre class="SCREEN">
-+deanimate-gifs{last}
-</pre>
- </td>
- </tr>
- </table>
- </dd>
- </dl>
- </div>
- </div>
-
- <div class="SECT3">
- <h4 class="SECT3"><a name="DOWNGRADE-HTTP-VERSION" id=
- "DOWNGRADE-HTTP-VERSION">8.5.13. downgrade-http-version</a></h4>
-
- <div class="VARIABLELIST">
- <dl>
- <dt>Typical use:</dt>
-
- <dd>
- <p>Work around (very rare) problems with HTTP/1.1</p>
- </dd>
-
- <dt>Effect:</dt>
-
- <dd>
- <p>Downgrades HTTP/1.1 client requests and server replies to
- HTTP/1.0.</p>
- </dd>
-
- <dt>Type:</dt>
-
- <dd>
- <p>Boolean.</p>
- </dd>
-
- <dt>Parameter:</dt>
-
- <dd>
- <p>N/A</p>
- </dd>
-
- <dt>Notes:</dt>
-
- <dd>
- <p>This is a left-over from the time when <span class=
- "APPLICATION">Privoxy</span> 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.</p>
-
- <p>Note that enabling this action is only a workaround. It
- should not be enabled for sites that work without it. While it
- shouldn't break any pages, it has an (usually negative)
- performance impact.</p>
-
- <p>If you come across a site where enabling this action helps,
- please report it, so the cause of the problem can be analyzed.
- If the problem turns out to be caused by a bug in <span class=
- "APPLICATION">Privoxy</span> it should be fixed so the
- following release works without the work around.</p>
- </dd>
-
- <dt>Example usage (section):</dt>
-
- <dd>
- <table border="0" bgcolor="#E0E0E0" width="90%">
- <tr>
- <td>
- <pre class="SCREEN">
-{+downgrade-http-version}
-problem-host.example.com
-</pre>
- </td>
- </tr>
- </table>
- </dd>
- </dl>
- </div>
- </div>
-
- <div class="SECT3">
- <h4 class="SECT3"><a name="EXTERNAL-FILTER" id=
- "EXTERNAL-FILTER">8.5.14. external-filter</a></h4>
-
- <div class="VARIABLELIST">
- <dl>
- <dt>Typical use:</dt>
-
- <dd>
- <p>Modify content using a programming language of your
- choice.</p>
- </dd>
-
- <dt>Effect:</dt>
-
- <dd>
- <p>All instances of text-based type, most notably HTML and
- JavaScript, to which this action applies, can be filtered
- on-the-fly through the specified external filter. By default
- plain text documents are exempted from filtering, because web
- servers often use the <tt class="LITERAL">text/plain</tt> MIME
- type for all files whose type they don't know.)</p>
- </dd>
-
- <dt>Type:</dt>
-
- <dd>
- <p>Multi-value.</p>
- </dd>
-
- <dt>Parameter:</dt>
-
- <dd>
- <p>The name of an external content filter, as defined in the
- <a href="filter-file.html">filter file</a>. External filters
- can be defined in one or more files as defined by the
- <tt class="LITERAL"><a href=
- "config.html#FILTERFILE">filterfile</a></tt> option in the
- <a href="config.html">config file</a>.</p>
-
- <p>When used in its negative form, and without parameters,
- <span class="emphasis"><i class="EMPHASIS">all</i></span>
- filtering with external filters is completely disabled.</p>
- </dd>
-
- <dt>Notes:</dt>
-
- <dd>
- <p>External filters are scripts or programs that can modify the
- content in case common <tt class="LITERAL"><a href=
- "actions-file.html#FILTER">filters</a></tt> aren't powerful
- enough. With the exception that this action doesn't use
- pcrs-based filters, the notes in the <tt class=
- "LITERAL"><a href="actions-file.html#FILTER">filter</a></tt>
- section apply.</p>
-
- <div class="WARNING">
- <table class="WARNING" border="1" width="90%">
- <tr>
- <td align="center"><b>Warning</b></td>
- </tr>
-
- <tr>
- <td align="left">
- <p>Currently external filters are executed with
- <span class="APPLICATION">Privoxy</span>'s privileges.
- Only use external filters you understand and trust.</p>
- </td>
- </tr>
- </table>
- </div>
-
- <p>This feature is experimental, the <tt class=
- "LITERAL"><a href=
- "filter-file.html#EXTERNAL-FILTER-SYNTAX">syntax</a></tt> may
- change in the future.</p>
- </dd>
-
- <dt>Example usage:</dt>
-
- <dd>
- <table border="0" bgcolor="#E0E0E0" width="90%">
- <tr>
- <td>
- <pre class="SCREEN">
-+external-filter{fancy-filter}
-</pre>
- </td>
- </tr>
- </table>
- </dd>
- </dl>
- </div>
- </div>
-
- <div class="SECT3">
- <h4 class="SECT3"><a name="FAST-REDIRECTS" id=
- "FAST-REDIRECTS">8.5.15. fast-redirects</a></h4>
-
- <div class="VARIABLELIST">
- <dl>
- <dt>Typical use:</dt>
-
- <dd>
- <p>Fool some click-tracking scripts and speed up indirect
- links.</p>
- </dd>
-
- <dt>Effect:</dt>
-
- <dd>
- <p>Detects redirection URLs and redirects the browser without
- contacting the redirection server first.</p>
- </dd>
-
- <dt>Type:</dt>
-
- <dd>
- <p>Parameterized.</p>
- </dd>
-
- <dt>Parameter:</dt>
-
- <dd>
- <ul>
- <li>
- <p><span class="QUOTE">"simple-check"</span> to just search
- for the string <span class="QUOTE">"http://"</span> to
- detect redirection URLs.</p>
- </li>
-
- <li>
- <p><span class="QUOTE">"check-decoded-url"</span> to decode
- URLs (if necessary) before searching for redirection
- URLs.</p>
- </li>
- </ul>
- </dd>
-
- <dt>Notes:</dt>
-
- <dd>
- <p>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: <span class=
- "QUOTE">"http://www.example.org/click-tracker.cgi?target=http%3a//www.example.net/"</span>.</p>
-
- <p>Sometimes, there are even multiple consecutive redirects
- encoded in the URL. These redirections via scripts make your
- web browsing more traceable, since the server from which you
- follow such a link can see where you go to. Apart from that,
- valuable bandwidth and time is wasted, while your browser asks
- the server for one redirect after the other. Plus, it feeds the
- advertisers.</p>
-
- <p>This feature is currently not very smart and is scheduled
- for improvement. If it is enabled by default, you will have to
- create some exceptions to this action. It can lead to failures
- in several ways:</p>
-
- <p>Not every URLs with other URLs as parameters is evil. Some
- sites offer a real service that requires this information to
- work. For example a validation service needs to know, which
- document to validate. <tt class="LITERAL">fast-redirects</tt>
- assumes that every URL parameter that looks like another URL is
- a redirection target, and will always redirect to the last one.
- Most of the time the assumption is correct, but if it isn't,
- the user gets redirected anyway.</p>
-
- <p>Another failure occurs if the URL contains other parameters
- after the URL parameter. The URL: <span class=
- "QUOTE">"http://www.example.org/?redirect=http%3a//www.example.net/&foo=bar"</span>.
- contains the redirection URL <span class=
- "QUOTE">"http://www.example.net/"</span>, followed by another
- parameter. <tt class="LITERAL">fast-redirects</tt> doesn't know
- that and will cause a redirect to <span class=
- "QUOTE">"http://www.example.net/&foo=bar"</span>. Depending
- on the target server configuration, the parameter will be
- silently ignored or lead to a <span class="QUOTE">"page not
- found"</span> error. You can prevent this problem by first
- using the <tt class="LITERAL"><a href=
- "actions-file.html#REDIRECT">redirect</a></tt> action to remove
- the last part of the URL, but it requires a little effort.</p>
-
- <p>To detect a redirection URL, <tt class=
- "LITERAL">fast-redirects</tt> only looks for the string
- <span class="QUOTE">"http://"</span>, either in plain text
- (invalid but often used) or encoded as <span class=
- "QUOTE">"http%3a//"</span>. Some sites use their own URL
- encoding scheme, encrypt the address of the target server or
- replace it with a database id. In theses cases <tt class=
- "LITERAL">fast-redirects</tt> is fooled and the request reaches
- the redirection server where it probably gets logged.</p>
- </dd>
-
- <dt>Example usage:</dt>
-
- <dd>
- <table border="0" bgcolor="#E0E0E0" width="90%">
- <tr>
- <td>
- <pre class="SCREEN">
- { +fast-redirects{simple-check} }
- one.example.com
-
- { +fast-redirects{check-decoded-url} }
- another.example.com/testing
-</pre>
- </td>
- </tr>
- </table>
- </dd>
- </dl>
- </div>
- </div>
-
- <div class="SECT3">
- <h4 class="SECT3"><a name="FILTER" id="FILTER">8.5.16.
- filter</a></h4>
-
- <div class="VARIABLELIST">
- <dl>
- <dt>Typical use:</dt>
-
- <dd>
- <p>Get rid of HTML and JavaScript annoyances, banner
- advertisements (by size), do fun text replacements, add
- personalized effects, etc.</p>
- </dd>
-
- <dt>Effect:</dt>
-
- <dd>
- <p>All instances of text-based type, most notably HTML and
- JavaScript, to which this action applies, can be filtered
- on-the-fly through the specified regular expression based
- substitutions. (Note: as of version 3.0.3 plain text documents
- are exempted from filtering, because web servers often use the
- <tt class="LITERAL">text/plain</tt> MIME type for all files
- whose type they don't know.)</p>
- </dd>
-
- <dt>Type:</dt>
-
- <dd>
- <p>Multi-value.</p>
- </dd>
-
- <dt>Parameter:</dt>
-
- <dd>
- <p>The name of a content filter, as defined in the <a href=
- "filter-file.html">filter file</a>. Filters can be defined in
- one or more files as defined by the <tt class=
- "LITERAL"><a href="config.html#FILTERFILE">filterfile</a></tt>
- option in the <a href="config.html">config file</a>. <tt class=
- "FILENAME">default.filter</tt> is the collection of filters
- supplied by the developers. Locally defined filters should go
- in their own file, such as <tt class=
- "FILENAME">user.filter</tt>.</p>
-
- <p>When used in its negative form, and without parameters,
- <span class="emphasis"><i class="EMPHASIS">all</i></span>
- filtering is completely disabled.</p>
- </dd>
-
- <dt>Notes:</dt>
-
- <dd>
- <p>For your convenience, there are a number of pre-defined
- filters available in the distribution filter file that you can
- use. See the examples below for a list.</p>
-
- <p>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. (The total time until
- the page is completely rendered doesn't change much, but it may
- be perceived as slower since the page is not incrementally
- displayed.) This effect will be more noticeable on slower
- connections.</p>
-
- <p><span class="QUOTE">"Rolling your own"</span> filters
- requires a knowledge of <a href=
- "http://en.wikipedia.org/wiki/Regular_expressions" target=
- "_top"><span class="QUOTE">"Regular Expressions"</span></a> and
- <a href="http://en.wikipedia.org/wiki/Html" target=
- "_top"><span class="QUOTE">"HTML"</span></a>. This is very
- powerful feature, and potentially very intrusive. Filters
- should be used with caution, and where an equivalent
- <span class="QUOTE">"action"</span> is not available.</p>
-
- <p>The amount of data that can be filtered is limited to the
- <tt class="LITERAL"><a href=
- "config.html#BUFFER-LIMIT">buffer-limit</a></tt> option in the
- main <a href="config.html">config file</a>. The default is 4096
- KB (4 Megs). Once this limit is exceeded, the buffered data,
- and all pending data, is passed through unfiltered.</p>
-
- <p>Inappropriate MIME types, such as zipped files, are not
- filtered at all. (Again, only text-based types except plain
- text). Encrypted SSL data (from HTTPS servers) cannot be
- filtered either, since this would violate the integrity of the
- secure transaction. In some situations it might be necessary to
- protect certain text, like source code, from filtering by
- defining appropriate <tt class="LITERAL">-filter</tt>
- exceptions.</p>
-
- <p>Compressed content can't be filtered either, but if
- <span class="APPLICATION">Privoxy</span> is compiled with zlib
- support and a supported compression algorithm is used (gzip or
- deflate), <span class="APPLICATION">Privoxy</span> can first
- decompress the content and then filter it.</p>
-
- <p>If you use a <span class="APPLICATION">Privoxy</span>
- version without zlib support, but want filtering to work on as
- much documents as possible, even those that would normally be
- sent compressed, you must use the <tt class="LITERAL"><a href=
- "actions-file.html#PREVENT-COMPRESSION">prevent-compression</a></tt>
- action in conjunction with <tt class="LITERAL">filter</tt>.</p>
-
- <p>Content filtering can achieve some of the same effects as
- the <tt class="LITERAL"><a href=
- "actions-file.html#BLOCK">block</a></tt> action, i.e. it can be
- used to block ads and banners. But the mechanism works quite
- differently. One effective use, is to block ad banners based on
- their size (see below), since many of these seem to be somewhat
- standardized.</p>
-
- <p><a href="contact.html">Feedback</a> with suggestions for new
- or improved filters is particularly welcome!</p>
-
- <p>The below list has only the names and a one-line description
- of each predefined filter. There are <a href=
- "filter-file.html#PREDEFINED-FILTERS">more verbose
- explanations</a> of what these filters do in the <a href=
- "filter-file.html">filter file chapter</a>.</p>
- </dd>
-
- <dt>Example usage (with filters from the distribution <tt class=
- "FILENAME">default.filter</tt> file). See <a href=
- "filter-file.html#PREDEFINED-FILTERS">the Predefined Filters
- section</a> for more explanation on each:</dt>
-
- <dd>
- <p><a name="FILTER-JS-ANNOYANCES" id=
- "FILTER-JS-ANNOYANCES"></a></p>
-
- <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td width="10%" align="left" valign="bottom">
+ <a href="config.html" accesskey="P">Prev</a>
+ </td>
+ <td width="80%" align="center" valign="bottom">
+ </td>
+ <td width="10%" align="right" valign="bottom">
+ <a href="filter-file.html" accesskey="N">Next</a>
+ </td>
+ </tr>
+ </table>
+ <hr align="LEFT" width="100%">
+ </div>
+ <div class="SECT1">
+ <h1 class="SECT1">
+ <a name="ACTIONS-FILE">8. Actions Files</a>
+ </h1>
+ <p>
+ The actions files are used to define what <span class="emphasis"><i
+ class="EMPHASIS">actions</i></span> <span class=
+ "APPLICATION">Privoxy</span> takes for which URLs, and thus
+ determines how ad images, cookies and various other aspects of HTTP
+ content and transactions are handled, and on which sites (or even
+ parts thereof). There are a number of such actions, with a wide range
+ of functionality. Each action does something a little different.
+ These actions give us a veritable arsenal of tools with which to
+ exert our control, preferences and independence. Actions can be
+ combined so that their effects are aggregated when applied against a
+ given set of URLs.
+ </p>
+ <p>
+ There are three action files included with <span class=
+ "APPLICATION">Privoxy</span> with differing purposes:
+ </p>
+ <p>
+ </p>
+ <ul>
+ <li>
+ <p>
+ <tt class="FILENAME">match-all.action</tt> - is used to define
+ which <span class="QUOTE">"actions"</span> relating to
+ banner-blocking, images, pop-ups, content modification, cookie
+ handling etc should be applied by default. It should be the first
+ actions file loaded
+ </p>
+ </li>
+ <li>
+ <p>
+ <tt class="FILENAME">default.action</tt> - defines many
+ exceptions (both positive and negative) from the default set of
+ actions that's configured in <tt class=
+ "FILENAME">match-all.action</tt>. It is a set of rules that
+ should work reasonably well as-is for most users. This file is
+ only supposed to be edited by the developers. It should be the
+ second actions file loaded.
+ </p>
+ </li>
+ <li>
+ <p>
+ <tt class="FILENAME">user.action</tt> - is intended to be for
+ local site preferences and exceptions. As an example, if your ISP
+ or your bank has specific requirements, and need special
+ handling, this kind of thing should go here. This file will not
+ be upgraded.
+ </p>
+ </li>
+ <li>
+ <p>
+ <span class="GUIBUTTON">Edit</span> <span class="GUIBUTTON">Set
+ to Cautious</span> <span class="GUIBUTTON">Set to Medium</span>
+ <span class="GUIBUTTON">Set to Advanced</span>
+ </p>
+ <p>
+ These have increasing levels of aggressiveness <span class=
+ "emphasis"><i class="EMPHASIS">and have no influence on your
+ browsing unless you select them explicitly in the
+ editor</i></span>. A default installation should be pre-set to
+ <tt class="LITERAL">Cautious</tt>. New users should try this for
+ a while before adjusting the settings to more aggressive levels.
+ The more aggressive the settings, then the more likelihood there
+ is of problems such as sites not working as they should.
+ </p>
+ <p>
+ The <span class="GUIBUTTON">Edit</span> button allows you to turn
+ each action on/off individually for fine-tuning. The <span class=
+ "GUIBUTTON">Cautious</span> button changes the actions list to
+ low/safe settings which will activate ad blocking and a minimal
+ set of <span class="APPLICATION">Privoxy</span>'s features, and
+ subsequently there will be less of a chance for accidental
+ problems. The <span class="GUIBUTTON">Medium</span> button sets
+ the list to a medium level of other features and a low level set
+ of privacy features. The <span class="GUIBUTTON">Advanced</span>
+ button sets the list to a high level of ad blocking and medium
+ level of privacy. See the chart below. The latter three buttons
+ over-ride any changes via with the <span class=
+ "GUIBUTTON">Edit</span> button. More fine-tuning can be done in
+ the lower sections of this internal page.
+ </p>
+ <p>
+ While the actions file editor allows to enable these settings in
+ all actions files, they are only supposed to be enabled in the
+ first one to make sure you don't unintentionally overrule earlier
+ rules.
+ </p>
+ <p>
+ The default profiles, and their associated actions, as
+ pre-defined in <tt class="FILENAME">default.action</tt> are:
+ </p>
+ <p>
+ </p>
+ <div class="TABLE">
+ <a name="AEN2791"></a>
+ <p>
+ <b>Table 1. Default Configurations</b>
+ </p>
+ <table border="1" frame="border" rules="all" class="CALSTABLE">
+ <col width="1*" title="C1">
+ <col width="1*" title="C2">
+ <col width="1*" title="C3">
+ <col width="1*" title="C4">
+ <thead>
+ <tr>
+ <th>
+ Feature
+ </th>
+ <th>
+ Cautious
+ </th>
+ <th>
+ Medium
+ </th>
+ <th>
+ Advanced
+ </th>
+ </tr>
+ </thead>
+ <tbody>
<tr>
<td>
- <pre class="SCREEN">
-+filter{js-annoyances} # Get rid of particularly annoying JavaScript abuse.
-</pre>
+ Ad-blocking Aggressiveness
+ </td>
+ <td>
+ medium
+ </td>
+ <td>
+ high
+ </td>
+ <td>
+ high
</td>
</tr>
- </table>
-
- <p><a name="FILTER-JS-EVENTS" id="FILTER-JS-EVENTS"></a></p>
-
- <table border="0" bgcolor="#E0E0E0" width="90%">
<tr>
<td>
- <pre class="SCREEN">
-+filter{js-events} # Kill JavaScript event bindings and timers (Radically destructive! Only for extra nasty sites).
-</pre>
+ Ad-filtering by size
+ </td>
+ <td>
+ no
+ </td>
+ <td>
+ yes
+ </td>
+ <td>
+ yes
</td>
</tr>
- </table>
-
- <p><a name="FILTER-HTML-ANNOYANCES" id=
- "FILTER-HTML-ANNOYANCES"></a></p>
-
- <table border="0" bgcolor="#E0E0E0" width="90%">
<tr>
<td>
- <pre class="SCREEN">
-+filter{html-annoyances} # Get rid of particularly annoying HTML abuse.
-</pre>
+ Ad-filtering by link
+ </td>
+ <td>
+ no
+ </td>
+ <td>
+ no
+ </td>
+ <td>
+ yes
</td>
</tr>
- </table>
-
- <p><a name="FILTER-CONTENT-COOKIES" id=
- "FILTER-CONTENT-COOKIES"></a></p>
-
- <table border="0" bgcolor="#E0E0E0" width="90%">
<tr>
<td>
- <pre class="SCREEN">
-+filter{content-cookies} # Kill cookies that come in the HTML or JS content.
-</pre>
+ Pop-up killing
+ </td>
+ <td>
+ blocks only
+ </td>
+ <td>
+ blocks only
+ </td>
+ <td>
+ blocks only
</td>
</tr>
- </table>
-
- <p><a name="FILTER-REFRESH-TAGS" id=
- "FILTER-REFRESH-TAGS"></a></p>
-
- <table border="0" bgcolor="#E0E0E0" width="90%">
<tr>
<td>
- <pre class="SCREEN">
-+filter{refresh-tags} # Kill automatic refresh tags if refresh time is larger than 9 seconds.
-</pre>
+ Privacy Features
+ </td>
+ <td>
+ low
+ </td>
+ <td>
+ medium
+ </td>
+ <td>
+ medium/high
</td>
</tr>
- </table>
-
- <p><a name="FILTER-UNSOLICITED-POPUPS" id=
- "FILTER-UNSOLICITED-POPUPS"></a></p>
-
- <table border="0" bgcolor="#E0E0E0" width="90%">
<tr>
<td>
- <pre class="SCREEN">
-+filter{unsolicited-popups} # Disable only unsolicited pop-up windows.
-</pre>
+ Cookie handling
+ </td>
+ <td>
+ none
+ </td>
+ <td>
+ session-only
+ </td>
+ <td>
+ kill
</td>
</tr>
- </table>
-
- <p><a name="FILTER-ALL-POPUPS" id="FILTER-ALL-POPUPS"></a></p>
-
- <table border="0" bgcolor="#E0E0E0" width="90%">
<tr>
<td>
- <pre class="SCREEN">
-+filter{all-popups} # Kill all popups in JavaScript and HTML.
-</pre>
+ Referer forging
+ </td>
+ <td>
+ no
+ </td>
+ <td>
+ yes
+ </td>
+ <td>
+ yes
</td>
</tr>
- </table>
-
- <p><a name="FILTER-IMG-REORDER" id=
- "FILTER-IMG-REORDER"></a></p>
-
- <table border="0" bgcolor="#E0E0E0" width="90%">
<tr>
<td>
- <pre class="SCREEN">
-+filter{img-reorder} # Reorder attributes in <img> tags to make the banners-by-* filters more effective.
-</pre>
+ GIF de-animation
+ </td>
+ <td>
+ no
+ </td>
+ <td>
+ yes
+ </td>
+ <td>
+ yes
</td>
</tr>
- </table>
-
- <p><a name="FILTER-BANNERS-BY-SIZE" id=
- "FILTER-BANNERS-BY-SIZE"></a></p>
-
- <table border="0" bgcolor="#E0E0E0" width="90%">
<tr>
<td>
- <pre class="SCREEN">
-+filter{banners-by-size} # Kill banners by size.
-</pre>
+ Fast redirects
+ </td>
+ <td>
+ no
+ </td>
+ <td>
+ no
+ </td>
+ <td>
+ yes
</td>
</tr>
- </table>
-
- <p><a name="FILTER-BANNERS-BY-LINK" id=
- "FILTER-BANNERS-BY-LINK"></a></p>
-
- <table border="0" bgcolor="#E0E0E0" width="90%">
<tr>
<td>
- <pre class="SCREEN">
-+filter{banners-by-link} # Kill banners by their links to known clicktrackers.
-</pre>
+ HTML taming
+ </td>
+ <td>
+ no
+ </td>
+ <td>
+ no
+ </td>
+ <td>
+ yes
</td>
</tr>
- </table>
-
- <p><a name="FILTER-WEBBUGS" id="FILTER-WEBBUGS"></a></p>
-
- <table border="0" bgcolor="#E0E0E0" width="90%">
<tr>
<td>
- <pre class="SCREEN">
-+filter{webbugs} # Squish WebBugs (1x1 invisible GIFs used for user tracking).
-</pre>
+ JavaScript taming
+ </td>
+ <td>
+ no
+ </td>
+ <td>
+ no
+ </td>
+ <td>
+ yes
</td>
</tr>
- </table>
-
- <p><a name="FILTER-TINY-TEXTFORMS" id=
- "FILTER-TINY-TEXTFORMS"></a></p>
-
- <table border="0" bgcolor="#E0E0E0" width="90%">
<tr>
<td>
- <pre class="SCREEN">
-+filter{tiny-textforms} # Extend those tiny textareas up to 40x80 and kill the hard wrap.
-</pre>
+ Web-bug killing
+ </td>
+ <td>
+ no
+ </td>
+ <td>
+ yes
+ </td>
+ <td>
+ yes
</td>
</tr>
- </table>
-
- <p><a name="FILTER-JUMPING-WINDOWS" id=
- "FILTER-JUMPING-WINDOWS"></a></p>
-
- <table border="0" bgcolor="#E0E0E0" width="90%">
<tr>
<td>
- <pre class="SCREEN">
-+filter{jumping-windows} # Prevent windows from resizing and moving themselves.
+ Image tag reordering
+ </td>
+ <td>
+ no
+ </td>
+ <td>
+ yes
+ </td>
+ <td>
+ yes
+ </td>
+ </tr>
+ </tbody>
+ </table>
+ </div>
+ </li>
+ </ul>
+
+ <p>
+ The list of actions files to be used are defined in the main
+ configuration file, and are processed in the order they are defined
+ (e.g. <tt class="FILENAME">default.action</tt> is typically processed
+ before <tt class="FILENAME">user.action</tt>). The content of these
+ can all be viewed and edited from <a href=
+ "http://config.privoxy.org/show-status" target=
+ "_top">http://config.privoxy.org/show-status</a>. The over-riding
+ principle when applying actions, is that the last action that matches
+ a given URL wins. The broadest, most general rules go first (defined
+ in <tt class="FILENAME">default.action</tt>), followed by any
+ exceptions (typically also in <tt class=
+ "FILENAME">default.action</tt>), which are then followed lastly by
+ any local preferences (typically in <span class="emphasis"><i class=
+ "EMPHASIS">user</i></span><tt class="FILENAME">.action</tt>).
+ Generally, <tt class="FILENAME">user.action</tt> has the last word.
+ </p>
+ <p>
+ An actions file typically has multiple sections. If you want to use
+ <span class="QUOTE">"aliases"</span> in an actions file, you have to
+ place the (optional) <a href="actions-file.html#ALIASES">alias
+ section</a> at the top of that file. Then comes the default set of
+ rules which will apply universally to all sites and pages (be <span
+ class="emphasis"><i class="EMPHASIS">very careful</i></span> with
+ using such a universal set in <tt class="FILENAME">user.action</tt>
+ or any other actions file after <tt class=
+ "FILENAME">default.action</tt>, because it will override the result
+ from consulting any previous file). And then below that, exceptions
+ to the defined universal policies. You can regard <tt class=
+ "FILENAME">user.action</tt> as an appendix to <tt class=
+ "FILENAME">default.action</tt>, with the advantage that it is a
+ separate file, which makes preserving your personal settings across
+ <span class="APPLICATION">Privoxy</span> upgrades easier.
+ </p>
+ <p>
+ Actions can be used to block anything you want, including ads,
+ banners, or just some obnoxious URL whose content you would rather
+ not see. Cookies can be accepted or rejected, or accepted only during
+ the current browser session (i.e. not written to disk), content can
+ be modified, some JavaScripts tamed, user-tracking fooled, and much
+ more. See below for a <a href="actions-file.html#ACTIONS">complete
+ list of actions</a>.
+ </p>
+ <div class="SECT2">
+ <h2 class="SECT2">
+ <a name="RIGHT-MIX">8.1. Finding the Right Mix</a>
+ </h2>
+ <p>
+ Note that some <a href="actions-file.html#ACTIONS">actions</a>,
+ like cookie suppression or script disabling, may render some sites
+ unusable that rely on these techniques to work properly. Finding
+ the right mix of actions is not always easy and certainly a matter
+ of personal taste. And, things can always change, requiring
+ refinements in the configuration. In general, it can be said that
+ the more <span class="QUOTE">"aggressive"</span> your default
+ settings (in the top section of the actions file) are, the more
+ exceptions for <span class="QUOTE">"trusted"</span> sites you will
+ have to make later. If, for example, you want to crunch all cookies
+ per default, you'll have to make exceptions from that rule for
+ sites that you regularly use and that require cookies for actually
+ useful purposes, like maybe your bank, favorite shop, or newspaper.
+ </p>
+ <p>
+ We have tried to provide you with reasonable rules to start from in
+ the distribution actions files. But there is no general rule of
+ thumb on these things. There just are too many variables, and sites
+ are constantly changing. Sooner or later you will want to change
+ the rules (and read this chapter again :).
+ </p>
+ </div>
+ <div class="SECT2">
+ <h2 class="SECT2">
+ <a name="HOW-TO-EDIT">8.2. How to Edit</a>
+ </h2>
+ <p>
+ The easiest way to edit the actions files is with a browser by
+ using our browser-based editor, which can be reached from <a href=
+ "http://config.privoxy.org/show-status" target=
+ "_top">http://config.privoxy.org/show-status</a>. Note: the config
+ file option <a href=
+ "config.html#ENABLE-EDIT-ACTIONS">enable-edit-actions</a> must be
+ enabled for this to work. The editor allows both fine-grained
+ control over every single feature on a per-URL basis, and easy
+ choosing from wholesale sets of defaults like <span class=
+ "QUOTE">"Cautious"</span>, <span class="QUOTE">"Medium"</span> or
+ <span class="QUOTE">"Advanced"</span>. Warning: the <span class=
+ "QUOTE">"Advanced"</span> setting is more aggressive, and will be
+ more likely to cause problems for some sites. Experienced users
+ only!
+ </p>
+ <p>
+ If you prefer plain text editing to GUIs, you can of course also
+ directly edit the the actions files with your favorite text editor.
+ Look at <tt class="FILENAME">default.action</tt> which is richly
+ commented with many good examples.
+ </p>
+ </div>
+ <div class="SECT2">
+ <h2 class="SECT2">
+ <a name="ACTIONS-APPLY">8.3. How Actions are Applied to
+ Requests</a>
+ </h2>
+ <p>
+ Actions files are divided into sections. There are special
+ sections, like the <span class="QUOTE">"<a href=
+ "actions-file.html#ALIASES">alias</a>"</span> sections which will
+ be discussed later. For now let's concentrate on regular sections:
+ They have a heading line (often split up to multiple lines for
+ readability) which consist of a list of actions, separated by
+ whitespace and enclosed in curly braces. Below that, there is a
+ list of URL and tag patterns, each on a separate line.
+ </p>
+ <p>
+ To determine which actions apply to a request, the URL of the
+ request is compared to all URL patterns in each <span class=
+ "QUOTE">"action file"</span>. Every time it matches, the list of
+ applicable actions for the request is incrementally updated, using
+ the heading of the section in which the pattern is located. The
+ same is done again for tags and tag patterns later on.
+ </p>
+ <p>
+ If multiple applying sections set the same action differently, the
+ last match wins. If not, the effects are aggregated. E.g. a URL
+ might match a regular section with a heading line of <tt class=
+ "LITERAL">{ +<a href=
+ "actions-file.html#HANDLE-AS-IMAGE">handle-as-image</a> }</tt>,
+ then later another one with just <tt class="LITERAL">{ +<a href=
+ "actions-file.html#BLOCK">block</a> }</tt>, resulting in <span
+ class="emphasis"><i class="EMPHASIS">both</i></span> actions to
+ apply. And there may well be cases where you will want to combine
+ actions together. Such a section then might look like:
+ </p>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="100%">
+ <tr>
+ <td>
+<pre class="SCREEN">
+ { +<tt class="LITERAL">handle-as-image</tt> +<tt class=
+"LITERAL">block{Banner ads.}</tt> }
+ # Block these as if they were images. Send no block page.
+ banners.example.com
+ media.example.com/.*banners
+ .example.com/images/ads/
+</pre>
+ </td>
+ </tr>
+ </table>
+
+ <p>
+ You can trace this process for URL patterns and any given URL by
+ visiting <a href="http://config.privoxy.org/show-url-info" target=
+ "_top">http://config.privoxy.org/show-url-info</a>.
+ </p>
+ <p>
+ Examples and more detail on this is provided in the Appendix, <a
+ href="appendix.html#ACTIONSANAT">Troubleshooting: Anatomy of an
+ Action</a> section.
+ </p>
+ </div>
+ <div class="SECT2">
+ <h2 class="SECT2">
+ <a name="AF-PATTERNS">8.4. Patterns</a>
+ </h2>
+ <p>
+ As mentioned, <span class="APPLICATION">Privoxy</span> uses <span
+ class="QUOTE">"patterns"</span> to determine what <span class=
+ "emphasis"><i class="EMPHASIS">actions</i></span> might apply to
+ which sites and pages your browser attempts to access. These <span
+ class="QUOTE">"patterns"</span> use wild card type <span class=
+ "emphasis"><i class="EMPHASIS">pattern</i></span> matching to
+ achieve a high degree of flexibility. This allows one expression to
+ be expanded and potentially match against many similar patterns.
+ </p>
+ <p>
+ Generally, an URL pattern has the form <tt class=
+ "LITERAL"><host><port>/<path></tt>, where the <tt
+ class="LITERAL"><host></tt>, the <tt class=
+ "LITERAL"><port></tt> and the <tt class=
+ "LITERAL"><path></tt> are optional. (This is why the special
+ <tt class="LITERAL">/</tt> pattern matches all URLs). Note that the
+ protocol portion of the URL pattern (e.g. <tt class=
+ "LITERAL">http://</tt>) should <span class="emphasis"><i class=
+ "EMPHASIS">not</i></span> be included in the pattern. This is
+ assumed already!
+ </p>
+ <p>
+ The pattern matching syntax is different for the host and path
+ parts of the URL. The host part uses a simple globbing type
+ matching technique, while the path part uses more flexible <a href=
+ "http://en.wikipedia.org/wiki/Regular_expressions" target=
+ "_top"><span class="QUOTE">"Regular Expressions"</span></a> (POSIX
+ 1003.2).
+ </p>
+ <p>
+ The port part of a pattern is a decimal port number preceded by a
+ colon (<tt class="LITERAL">:</tt>). If the host part contains a
+ numerical IPv6 address, it has to be put into angle brackets (<tt
+ class="LITERAL"><</tt>, <tt class="LITERAL">></tt>).
+ </p>
+ <div class="VARIABLELIST">
+ <dl>
+ <dt>
+ <tt class="LITERAL">www.example.com/</tt>
+ </dt>
+ <dd>
+ <p>
+ is a host-only pattern and will match any request to <tt
+ class="LITERAL">www.example.com</tt>, regardless of which
+ document on that server is requested. So ALL pages in this
+ domain would be covered by the scope of this action. Note
+ that a simple <tt class="LITERAL">example.com</tt> is
+ different and would NOT match.
+ </p>
+ </dd>
+ <dt>
+ <tt class="LITERAL">www.example.com</tt>
+ </dt>
+ <dd>
+ <p>
+ means exactly the same. For host-only patterns, the trailing
+ <tt class="LITERAL">/</tt> may be omitted.
+ </p>
+ </dd>
+ <dt>
+ <tt class="LITERAL">www.example.com/index.html</tt>
+ </dt>
+ <dd>
+ <p>
+ matches all the documents on <tt class=
+ "LITERAL">www.example.com</tt> whose name starts with <tt
+ class="LITERAL">/index.html</tt>.
+ </p>
+ </dd>
+ <dt>
+ <tt class="LITERAL">www.example.com/index.html$</tt>
+ </dt>
+ <dd>
+ <p>
+ matches only the single document <tt class=
+ "LITERAL">/index.html</tt> on <tt class=
+ "LITERAL">www.example.com</tt>.
+ </p>
+ </dd>
+ <dt>
+ <tt class="LITERAL">/index.html$</tt>
+ </dt>
+ <dd>
+ <p>
+ matches the document <tt class="LITERAL">/index.html</tt>,
+ regardless of the domain, i.e. on <span class="emphasis"><i
+ class="EMPHASIS">any</i></span> web server anywhere.
+ </p>
+ </dd>
+ <dt>
+ <tt class="LITERAL">/</tt>
+ </dt>
+ <dd>
+ <p>
+ Matches any URL because there's no requirement for either the
+ domain or the path to match anything.
+ </p>
+ </dd>
+ <dt>
+ <tt class="LITERAL">:8000/</tt>
+ </dt>
+ <dd>
+ <p>
+ Matches any URL pointing to TCP port 8000.
+ </p>
+ </dd>
+ <dt>
+ <tt class="LITERAL">10.0.0.1/</tt>
+ </dt>
+ <dd>
+ <p>
+ Matches any URL with the host address <tt class=
+ "LITERAL">10.0.0.1</tt>. (Note that the real URL uses plain
+ brackets, not angle brackets.)
+ </p>
+ </dd>
+ <dt>
+ <tt class="LITERAL"><2001:db8::1>/</tt>
+ </dt>
+ <dd>
+ <p>
+ Matches any URL with the host address <tt class=
+ "LITERAL">2001:db8::1</tt>. (Note that the real URL uses
+ plain brackets, not angle brackets.)
+ </p>
+ </dd>
+ <dt>
+ <tt class="LITERAL">index.html</tt>
+ </dt>
+ <dd>
+ <p>
+ matches nothing, since it would be interpreted as a domain
+ name and there is no top-level domain called <tt class=
+ "LITERAL">.html</tt>. So its a mistake.
+ </p>
+ </dd>
+ </dl>
+ </div>
+ <div class="SECT3">
+ <h3 class="SECT3">
+ <a name="HOST-PATTERN">8.4.1. The Host Pattern</a>
+ </h3>
+ <p>
+ The matching of the host part offers some flexible options: if
+ the host pattern starts or ends with a dot, it becomes unanchored
+ at that end. The host pattern is often referred to as domain
+ pattern as it is usually used to match domain names and not IP
+ addresses. For example:
+ </p>
+ <div class="VARIABLELIST">
+ <dl>
+ <dt>
+ <tt class="LITERAL">.example.com</tt>
+ </dt>
+ <dd>
+ <p>
+ matches any domain with first-level domain <tt class=
+ "LITERAL">com</tt> and second-level domain <tt class=
+ "LITERAL">example</tt>. For example <tt class=
+ "LITERAL">www.example.com</tt>, <tt class=
+ "LITERAL">example.com</tt> and <tt class=
+ "LITERAL">foo.bar.baz.example.com</tt>. Note that it
+ wouldn't match if the second-level domain was <tt class=
+ "LITERAL">another-example</tt>.
+ </p>
+ </dd>
+ <dt>
+ <tt class="LITERAL">www.</tt>
+ </dt>
+ <dd>
+ <p>
+ matches any domain that <span class="emphasis"><i class=
+ "EMPHASIS">STARTS</i></span> with <tt class=
+ "LITERAL">www.</tt> (It also matches the domain <tt class=
+ "LITERAL">www</tt> but most of the time that doesn't
+ matter.)
+ </p>
+ </dd>
+ <dt>
+ <tt class="LITERAL">.example.</tt>
+ </dt>
+ <dd>
+ <p>
+ matches any domain that <span class="emphasis"><i class=
+ "EMPHASIS">CONTAINS</i></span> <tt class=
+ "LITERAL">.example.</tt>. And, by the way, also included
+ would be any files or documents that exist within that
+ domain since no path limitations are specified. (Correctly
+ speaking: It matches any FQDN that contains <tt class=
+ "LITERAL">example</tt> as a domain.) This might be <tt
+ class="LITERAL">www.example.com</tt>, <tt class=
+ "LITERAL">news.example.de</tt>, or <tt class=
+ "LITERAL">www.example.net/cgi/testing.pl</tt> for instance.
+ All these cases are matched.
+ </p>
+ </dd>
+ </dl>
+ </div>
+ <p>
+ Additionally, there are wild-cards that you can use in the domain
+ names themselves. These work similarly to shell globbing type
+ wild-cards: <span class="QUOTE">"*"</span> represents zero or
+ more arbitrary characters (this is equivalent to the <a href=
+ "http://en.wikipedia.org/wiki/Regular_expressions" target=
+ "_top"><span class="QUOTE">"Regular Expression"</span></a> based
+ syntax of <span class="QUOTE">".*"</span>), <span class=
+ "QUOTE">"?"</span> represents any single character (this is
+ equivalent to the regular expression syntax of a simple <span
+ class="QUOTE">"."</span>), and you can define <span class=
+ "QUOTE">"character classes"</span> in square brackets which is
+ similar to the same regular expression technique. All of this can
+ be freely mixed:
+ </p>
+ <div class="VARIABLELIST">
+ <dl>
+ <dt>
+ <tt class="LITERAL">ad*.example.com</tt>
+ </dt>
+ <dd>
+ <p>
+ matches <span class="QUOTE">"adserver.example.com"</span>,
+ <span class="QUOTE">"ads.example.com"</span>, etc but not
+ <span class="QUOTE">"sfads.example.com"</span>
+ </p>
+ </dd>
+ <dt>
+ <tt class="LITERAL">*ad*.example.com</tt>
+ </dt>
+ <dd>
+ <p>
+ matches all of the above, and then some.
+ </p>
+ </dd>
+ <dt>
+ <tt class="LITERAL">.?pix.com</tt>
+ </dt>
+ <dd>
+ <p>
+ matches <tt class="LITERAL">www.ipix.com</tt>, <tt class=
+ "LITERAL">pictures.epix.com</tt>, <tt class=
+ "LITERAL">a.b.c.d.e.upix.com</tt> etc.
+ </p>
+ </dd>
+ <dt>
+ <tt class="LITERAL">www[1-9a-ez].example.c*</tt>
+ </dt>
+ <dd>
+ <p>
+ matches <tt class="LITERAL">www1.example.com</tt>, <tt
+ class="LITERAL">www4.example.cc</tt>, <tt class=
+ "LITERAL">wwwd.example.cy</tt>, <tt class=
+ "LITERAL">wwwz.example.com</tt> etc., but <span class=
+ "emphasis"><i class="EMPHASIS">not</i></span> <tt class=
+ "LITERAL">wwww.example.com</tt>.
+ </p>
+ </dd>
+ </dl>
+ </div>
+ <p>
+ While flexible, this is not the sophistication of full regular
+ expression based syntax.
+ </p>
+ </div>
+ <div class="SECT3">
+ <h3 class="SECT3">
+ <a name="PATH-PATTERN">8.4.2. The Path Pattern</a>
+ </h3>
+ <p>
+ <span class="APPLICATION">Privoxy</span> uses <span class=
+ "QUOTE">"modern"</span> POSIX 1003.2 <a href=
+ "http://en.wikipedia.org/wiki/Regular_expressions" target=
+ "_top"><span class="QUOTE">"Regular Expressions"</span></a> for
+ matching the path portion (after the slash), and is thus more
+ flexible.
+ </p>
+ <p>
+ There is an <a href="appendix.html#REGEX">Appendix</a> with a
+ brief quick-start into regular expressions, you also might want
+ to have a look at your operating system's documentation on
+ regular expressions (try <tt class="LITERAL">man re_format</tt>).
+ </p>
+ <p>
+ Note that the path pattern is automatically left-anchored at the
+ <span class="QUOTE">"/"</span>, i.e. it matches as if it would
+ start with a <span class="QUOTE">"^"</span> (regular expression
+ speak for the beginning of a line).
+ </p>
+ <p>
+ Please also note that matching in the path is <span class=
+ "emphasis"><i class="EMPHASIS">CASE INSENSITIVE</i></span> by
+ default, but you can switch to case sensitive at any point in the
+ pattern by using the <span class="QUOTE">"(?-i)"</span> switch:
+ <tt class="LITERAL">www.example.com/(?-i)PaTtErN.*</tt> will
+ match only documents whose path starts with <tt class=
+ "LITERAL">PaTtErN</tt> in <span class="emphasis"><i class=
+ "EMPHASIS">exactly</i></span> this capitalization.
+ </p>
+ <div class="VARIABLELIST">
+ <dl>
+ <dt>
+ <tt class="LITERAL">.example.com/.*</tt>
+ </dt>
+ <dd>
+ <p>
+ Is equivalent to just <span class=
+ "QUOTE">".example.com"</span>, since any documents within
+ that domain are matched with or without the <span class=
+ "QUOTE">".*"</span> regular expression. This is redundant
+ </p>
+ </dd>
+ <dt>
+ <tt class="LITERAL">.example.com/.*/index.html$</tt>
+ </dt>
+ <dd>
+ <p>
+ Will match any page in the domain of <span class=
+ "QUOTE">"example.com"</span> that is named <span class=
+ "QUOTE">"index.html"</span>, and that is part of some path.
+ For example, it matches <span class=
+ "QUOTE">"www.example.com/testing/index.html"</span> but NOT
+ <span class="QUOTE">"www.example.com/index.html"</span>
+ because the regular expression called for at least two
+ <span class="QUOTE">"/'s"</span>, thus the path
+ requirement. It also would match <span class=
+ "QUOTE">"www.example.com/testing/index_html"</span>,
+ because of the special meta-character <span class=
+ "QUOTE">"."</span>.
+ </p>
+ </dd>
+ <dt>
+ <tt class="LITERAL">.example.com/(.*/)?index\.html$</tt>
+ </dt>
+ <dd>
+ <p>
+ This regular expression is conditional so it will match any
+ page named <span class="QUOTE">"index.html"</span>
+ regardless of path which in this case can have one or more
+ <span class="QUOTE">"/'s"</span>. And this one must contain
+ exactly <span class="QUOTE">".html"</span> (but does not
+ have to end with that!).
+ </p>
+ </dd>
+ <dt>
+ <tt class=
+ "LITERAL">.example.com/(.*/)(ads|banners?|junk)</tt>
+ </dt>
+ <dd>
+ <p>
+ This regular expression will match any path of <span class=
+ "QUOTE">"example.com"</span> that contains any of the words
+ <span class="QUOTE">"ads"</span>, <span class=
+ "QUOTE">"banner"</span>, <span class=
+ "QUOTE">"banners"</span> (because of the <span class=
+ "QUOTE">"?"</span>) or <span class="QUOTE">"junk"</span>.
+ The path does not have to end in these words, just contain
+ them.
+ </p>
+ </dd>
+ <dt>
+ <tt class=
+ "LITERAL">.example.com/(.*/)(ads|banners?|junk)/.*\.(jpe?g|gif|png)$</tt>
+ </dt>
+ <dd>
+ <p>
+ This is very much the same as above, except now it must end
+ in either <span class="QUOTE">".jpg"</span>, <span class=
+ "QUOTE">".jpeg"</span>, <span class="QUOTE">".gif"</span>
+ or <span class="QUOTE">".png"</span>. So this one is
+ limited to common image formats.
+ </p>
+ </dd>
+ </dl>
+ </div>
+ <p>
+ There are many, many good examples to be found in <tt class=
+ "FILENAME">default.action</tt>, and more tutorials below in <a
+ href="appendix.html#REGEX">Appendix on regular expressions</a>.
+ </p>
+ </div>
+ <div class="SECT3">
+ <h3 class="SECT3">
+ <a name="TAG-PATTERN">8.4.3. The Request Tag Pattern</a>
+ </h3>
+ <p>
+ Request tag patterns are used to change the applying actions
+ based on the request's tags. Tags can be created based on HTTP
+ headers with either the <a href=
+ "actions-file.html#CLIENT-HEADER-TAGGER">client-header-tagger</a>
+ or the <a href=
+ "actions-file.html#SERVER-HEADER-TAGGER">server-header-tagger</a>
+ action.
+ </p>
+ <p>
+ Request tag patterns have to start with <span class=
+ "QUOTE">"TAG:"</span>, so <span class=
+ "APPLICATION">Privoxy</span> can tell them apart from other
+ patterns. Everything after the colon including white space, is
+ interpreted as a regular expression with path pattern syntax,
+ except that tag patterns aren't left-anchored automatically
+ (<span class="APPLICATION">Privoxy</span> doesn't silently add a
+ <span class="QUOTE">"^"</span>, you have to do it yourself if you
+ need it).
+ </p>
+ <p>
+ To match all requests that are tagged with <span class=
+ "QUOTE">"foo"</span> your pattern line should be <span class=
+ "QUOTE">"TAG:^foo$"</span>, <span class="QUOTE">"TAG:foo"</span>
+ would work as well, but it would also match requests whose tags
+ contain <span class="QUOTE">"foo"</span> somewhere. <span class=
+ "QUOTE">"TAG: foo"</span> wouldn't work as it requires white
+ space.
+ </p>
+ <p>
+ Sections can contain URL and request tag patterns at the same
+ time, but request tag patterns are checked after the URL patterns
+ and thus always overrule them, even if they are located before
+ the URL patterns.
+ </p>
+ <p>
+ Once a new request tag is added, Privoxy checks right away if
+ it's matched by one of the request tag patterns and updates the
+ action settings accordingly. As a result request tags can be used
+ to activate other tagger actions, as long as these other taggers
+ look for headers that haven't already be parsed.
+ </p>
+ <p>
+ For example you could tag client requests which use the <tt
+ class="LITERAL">POST</tt> method, then use this tag to activate
+ another tagger that adds a tag if cookies are sent, and then use
+ a block action based on the cookie tag. This allows the outcome
+ of one action, to be input into a subsequent action. However if
+ you'd reverse the position of the described taggers, and
+ activated the method tagger based on the cookie tagger, no method
+ tags would be created. The method tagger would look for the
+ request line, but at the time the cookie tag is created, the
+ request line has already been parsed.
+ </p>
+ <p>
+ While this is a limitation you should be aware of, this kind of
+ indirection is seldom needed anyway and even the example doesn't
+ make too much sense.
+ </p>
+ </div>
+ <div class="SECT3">
+ <h3 class="SECT3">
+ <a name="NEGATIVE-TAG-PATTERNS">8.4.4. The Negative Request Tag
+ Patterns</a>
+ </h3>
+ <p>
+ To match requests that do not have a certain request tag, specify
+ a negative tag pattern by prefixing the tag pattern line with
+ either <span class="QUOTE">"NO-REQUEST-TAG:"</span> or <span
+ class="QUOTE">"NO-RESPONSE-TAG:"</span> instead of <span class=
+ "QUOTE">"TAG:"</span>.
+ </p>
+ <p>
+ Negative request tag patterns created with <span class=
+ "QUOTE">"NO-REQUEST-TAG:"</span> are checked after all client
+ headers are scanned, the ones created with <span class=
+ "QUOTE">"NO-RESPONSE-TAG:"</span> are checked after all server
+ headers are scanned. In both cases all the created tags are
+ considered.
+ </p>
+ </div>
+ <div class="SECT3">
+ <h3 class="SECT3">
+ <a name="CLIENT-TAG-PATTERN">8.4.5. The Client Tag Pattern</a>
+ </h3>
+ <div class="WARNING">
+ <table class="WARNING" border="1" width="100%">
+ <tr>
+ <td align="CENTER">
+ <b>Warning</b>
+ </td>
+ </tr>
+ <tr>
+ <td align="LEFT">
+ <p>
+ This is an experimental feature. The syntax is likely to
+ change in future versions.
+ </p>
+ </td>
+ </tr>
+ </table>
+ </div>
+ <p>
+ Client tag patterns are not set based on HTTP headers but based
+ on the client's IP address. Users can enable them themselves, but
+ the Privoxy admin controls which tags are available and what
+ their effect is.
+ </p>
+ <p>
+ After a client-specific tag has been defined with the <a href=
+ "config.html#CLIENT-SPECIFIC-TAG">client-specific-tag</a>,
+ directive, action sections can be activated based on the tag by
+ using a CLIENT-TAG pattern. The CLIENT-TAG pattern is evaluated
+ at the same priority as URL patterns, as a result the last
+ matching pattern wins. Tags that are created based on client or
+ server headers are evaluated later on and can overrule CLIENT-TAG
+ and URL patterns!
+ </p>
+ <p>
+ The tag is set for all requests that come from clients that
+ requested it to be set. Note that "clients" are differentiated by
+ IP address, if the IP address changes the tag has to be requested
+ again.
+ </p>
+ <p>
+ Clients can request tags to be set by using the CGI interface <a
+ href="http://config.privoxy.org/client-tags" target=
+ "_top">http://config.privoxy.org/client-tags</a>.
+ </p>
+ <p>
+ Example:
+ </p>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="100%">
+ <tr>
+ <td>
+<pre class="SCREEN">
+# If the admin defined the client-specific-tag circumvent-blocks,
+# and the request comes from a client that previously requested
+# the tag to be set, overrule all previous +block actions that
+# are enabled based on URL to CLIENT-TAG patterns.
+{-block}
+CLIENT-TAG:^circumvent-blocks$
+
+# This section is not overruled because it's located after
+# the previous one.
+{+block{Nobody is supposed to request this.}}
+example.org/blocked-example-page
+</pre>
+ </td>
+ </tr>
+ </table>
+ </div>
+ </div>
+ <div class="SECT2">
+ <h2 class="SECT2">
+ <a name="ACTIONS">8.5. Actions</a>
+ </h2>
+ <p>
+ All actions are disabled by default, until they are explicitly
+ enabled somewhere in an actions file. Actions are turned on if
+ preceded with a <span class="QUOTE">"+"</span>, and turned off if
+ preceded with a <span class="QUOTE">"-"</span>. So a <tt class=
+ "LITERAL">+action</tt> means <span class="QUOTE">"do that
+ action"</span>, e.g. <tt class="LITERAL">+block</tt> means <span
+ class="QUOTE">"please block URLs that match the following
+ patterns"</span>, and <tt class="LITERAL">-block</tt> means <span
+ class="QUOTE">"don't block URLs that match the following patterns,
+ even if <tt class="LITERAL">+block</tt> previously
+ applied."</span>
+ </p>
+ <p>
+ Again, actions are invoked by placing them on a line, enclosed in
+ curly braces and separated by whitespace, like in <tt class=
+ "LITERAL">{+some-action -some-other-action{some-parameter}}</tt>,
+ followed by a list of URL patterns, one per line, to which they
+ apply. Together, the actions line and the following pattern lines
+ make up a section of the actions file.
+ </p>
+ <p>
+ Actions fall into three categories:
+ </p>
+ <p>
+ </p>
+ <ul>
+ <li>
+ <p>
+ Boolean, i.e the action can only be <span class=
+ "QUOTE">"enabled"</span> or <span class=
+ "QUOTE">"disabled"</span>. Syntax:
+ </p>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
+ +<tt class="REPLACEABLE"><i>name</i></tt> # enable action <tt class=
+"REPLACEABLE"><i>name</i></tt>
+ -<tt class="REPLACEABLE"><i>name</i></tt> # disable action <tt
+class="REPLACEABLE"><i>name</i></tt>
+</pre>
+ </td>
+ </tr>
+ </table>
+
+ <p>
+ Example: <tt class="LITERAL">+handle-as-image</tt>
+ </p>
+ </li>
+ <li>
+ <p>
+ Parameterized, where some value is required in order to enable
+ this type of action. Syntax:
+ </p>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
+ +<tt class="REPLACEABLE"><i>name</i></tt>{<tt class=
+"REPLACEABLE"><i>param</i></tt>} # enable action and set parameter to <tt
+class="REPLACEABLE"><i>param</i></tt>,
+ # overwriting parameter from previous match if necessary
+ -<tt class=
+"REPLACEABLE"><i>name</i></tt> # disable action. The parameter can be omitted
+</pre>
+ </td>
+ </tr>
+ </table>
+
+ <p>
+ Note that if the URL matches multiple positive forms of a
+ parameterized action, the last match wins, i.e. the params from
+ earlier matches are simply ignored.
+ </p>
+ <p>
+ Example: <tt class="LITERAL">+hide-user-agent{Mozilla/5.0 (X11;
+ U; FreeBSD i386; en-US; rv:1.8.1.4) Gecko/20070602
+ Firefox/2.0.0.4}</tt>
+ </p>
+ </li>
+ <li>
+ <p>
+ Multi-value. These look exactly like parameterized actions, but
+ they behave differently: If the action applies multiple times
+ to the same URL, but with different parameters, <span class=
+ "emphasis"><i class="EMPHASIS">all</i></span> the parameters
+ from <span class="emphasis"><i class="EMPHASIS">all</i></span>
+ matches are remembered. This is used for actions that can be
+ executed for the same request repeatedly, like adding multiple
+ headers, or filtering through multiple filters. Syntax:
+ </p>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
+ +<tt class="REPLACEABLE"><i>name</i></tt>{<tt class=
+"REPLACEABLE"><i>param</i></tt>} # enable action and add <tt class=
+"REPLACEABLE"><i>param</i></tt> to the list of parameters
+ -<tt class="REPLACEABLE"><i>name</i></tt>{<tt class=
+"REPLACEABLE"><i>param</i></tt>} # remove the parameter <tt class=
+"REPLACEABLE"><i>param</i></tt> from the list of parameters
+ # If it was the last one left, disable the action.
+ <tt class=
+"REPLACEABLE"><i>-name</i></tt> # disable this action completely and remove all parameters from the list
+</pre>
+ </td>
+ </tr>
+ </table>
+
+ <p>
+ Examples: <tt class="LITERAL">+add-header{X-Fun-Header: Some
+ text}</tt> and <tt class=
+ "LITERAL">+filter{html-annoyances}</tt>
+ </p>
+ </li>
+ </ul>
+
+ <p>
+ If nothing is specified in any actions file, no <span class=
+ "QUOTE">"actions"</span> are taken. So in this case <span class=
+ "APPLICATION">Privoxy</span> would just be a normal, non-blocking,
+ non-filtering proxy. You must specifically enable the privacy and
+ blocking features you need (although the provided default actions
+ files will give a good starting point).
+ </p>
+ <p>
+ Later defined action sections always over-ride earlier ones of the
+ same type. So exceptions to any rules you make, should come in the
+ latter part of the file (or in a file that is processed later when
+ using multiple actions files such as <tt class=
+ "FILENAME">user.action</tt>). For multi-valued actions, the actions
+ are applied in the order they are specified. Actions files are
+ processed in the order they are defined in <tt class=
+ "FILENAME">config</tt> (the default installation has three actions
+ files). It also quite possible for any given URL to match more than
+ one <span class="QUOTE">"pattern"</span> (because of wildcards and
+ regular expressions), and thus to trigger more than one set of
+ actions! Last match wins.
+ </p>
+ <p>
+ The list of valid <span class="APPLICATION">Privoxy</span> actions
+ are:
+ </p>
+ <div class="SECT3">
+ <h4 class="SECT3">
+ <a name="ADD-HEADER">8.5.1. add-header</a>
+ </h4>
+ <div class="VARIABLELIST">
+ <dl>
+ <dt>
+ Typical use:
+ </dt>
+ <dd>
+ <p>
+ Confuse log analysis, custom applications
+ </p>
+ </dd>
+ <dt>
+ Effect:
+ </dt>
+ <dd>
+ <p>
+ Sends a user defined HTTP header to the web server.
+ </p>
+ </dd>
+ <dt>
+ Type:
+ </dt>
+ <dd>
+ <p>
+ Multi-value.
+ </p>
+ </dd>
+ <dt>
+ Parameter:
+ </dt>
+ <dd>
+ <p>
+ Any string value is possible. Validity of the defined HTTP
+ headers is not checked. It is recommended that you use the
+ <span class="QUOTE">"<tt class="LITERAL">X-</tt>"</span>
+ prefix for custom headers.
+ </p>
+ </dd>
+ <dt>
+ Notes:
+ </dt>
+ <dd>
+ <p>
+ This action may be specified multiple times, in order to
+ define multiple headers. This is rarely needed for the
+ typical user. If you don't know what <span class=
+ "QUOTE">"HTTP headers"</span> are, you definitely don't
+ need to worry about this one.
+ </p>
+ <p>
+ Headers added by this action are not modified by other
+ actions.
+ </p>
+ </dd>
+ <dt>
+ Example usage:
+ </dt>
+ <dd>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
+# Add a DNT ("Do not track") header to all requests,
+# event to those that already have one.
+#
+# This is just an example, not a recommendation.
+#
+# There is no reason to believe that user-tracking websites care
+# about the DNT header and depending on the User-Agent, adding the
+# header may make user-tracking easier.
+{+add-header{DNT: 1}}
+/
+</pre>
+ </td>
+ </tr>
+ </table>
+ </dd>
+ </dl>
+ </div>
+ </div>
+ <div class="SECT3">
+ <h4 class="SECT3">
+ <a name="BLOCK">8.5.2. block</a>
+ </h4>
+ <div class="VARIABLELIST">
+ <dl>
+ <dt>
+ Typical use:
+ </dt>
+ <dd>
+ <p>
+ Block ads or other unwanted content
+ </p>
+ </dd>
+ <dt>
+ Effect:
+ </dt>
+ <dd>
+ <p>
+ Requests for URLs to which this action applies are blocked,
+ i.e. the requests are trapped by <span class=
+ "APPLICATION">Privoxy</span> and the requested URL is never
+ retrieved, but is answered locally with a substitute page
+ or image, as determined by the <tt class="LITERAL"><a href=
+ "actions-file.html#HANDLE-AS-IMAGE">handle-as-image</a></tt>,
+ <tt class="LITERAL"><a href=
+ "actions-file.html#SET-IMAGE-BLOCKER">set-image-blocker</a></tt>,
+ and <tt class="LITERAL"><a href=
+ "actions-file.html#HANDLE-AS-EMPTY-DOCUMENT">handle-as-empty-document</a></tt>
+ actions.
+ </p>
+ </dd>
+ <dt>
+ Type:
+ </dt>
+ <dd>
+ <p>
+ Parameterized.
+ </p>
+ </dd>
+ <dt>
+ Parameter:
+ </dt>
+ <dd>
+ <p>
+ A block reason that should be given to the user.
+ </p>
+ </dd>
+ <dt>
+ Notes:
+ </dt>
+ <dd>
+ <p>
+ <span class="APPLICATION">Privoxy</span> sends a special
+ <span class="QUOTE">"BLOCKED"</span> page for requests to
+ blocked pages. This page contains the block reason given as
+ parameter, a link to find out why the block action applies,
+ and a click-through to the blocked content (the latter only
+ if the force feature is available and enabled).
+ </p>
+ <p>
+ A very important exception occurs if <span class=
+ "emphasis"><i class="EMPHASIS">both</i></span> <tt class=
+ "LITERAL">block</tt> and <tt class="LITERAL"><a href=
+ "actions-file.html#HANDLE-AS-IMAGE">handle-as-image</a></tt>,
+ apply to the same request: it will then be replaced by an
+ image. If <tt class="LITERAL"><a href=
+ "actions-file.html#SET-IMAGE-BLOCKER">set-image-blocker</a></tt>
+ (see below) also applies, the type of image will be
+ determined by its parameter, if not, the standard
+ checkerboard pattern is sent.
+ </p>
+ <p>
+ It is important to understand this process, in order to
+ understand how <span class="APPLICATION">Privoxy</span>
+ deals with ads and other unwanted content. Blocking is a
+ core feature, and one upon which various other features
+ depend.
+ </p>
+ <p>
+ The <tt class="LITERAL"><a href=
+ "actions-file.html#FILTER">filter</a></tt> action can
+ perform a very similar task, by <span class=
+ "QUOTE">"blocking"</span> 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.
+ </p>
+ </dd>
+ <dt>
+ Example usage (section):
+ </dt>
+ <dd>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
+{+block{No nasty stuff for you.}}
+# Block and replace with "blocked" page
+ .nasty-stuff.example.com
+
+{+block{Doubleclick banners.} +handle-as-image}
+# Block and replace with image
+ .ad.doubleclick.net
+ .ads.r.us/banners/
+
+{+block{Layered ads.} +handle-as-empty-document}
+# Block and then ignore
+ adserver.example.net/.*\.js$
+</pre>
+ </td>
+ </tr>
+ </table>
+ </dd>
+ </dl>
+ </div>
+ </div>
+ <div class="SECT3">
+ <h4 class="SECT3">
+ <a name="CHANGE-X-FORWARDED-FOR">8.5.3.
+ change-x-forwarded-for</a>
+ </h4>
+ <div class="VARIABLELIST">
+ <dl>
+ <dt>
+ Typical use:
+ </dt>
+ <dd>
+ <p>
+ Improve privacy by not forwarding the source of the request
+ in the HTTP headers.
+ </p>
+ </dd>
+ <dt>
+ Effect:
+ </dt>
+ <dd>
+ <p>
+ Deletes the <span class="QUOTE">"X-Forwarded-For:"</span>
+ HTTP header from the client request, or adds a new one.
+ </p>
+ </dd>
+ <dt>
+ Type:
+ </dt>
+ <dd>
+ <p>
+ Parameterized.
+ </p>
+ </dd>
+ <dt>
+ Parameter:
+ </dt>
+ <dd>
+ <ul>
+ <li>
+ <p>
+ <span class="QUOTE">"block"</span> to delete the
+ header.
+ </p>
+ </li>
+ <li>
+ <p>
+ <span class="QUOTE">"add"</span> to create the header
+ (or append the client's IP address to an already
+ existing one).
+ </p>
+ </li>
+ </ul>
+ </dd>
+ <dt>
+ Notes:
+ </dt>
+ <dd>
+ <p>
+ It is safe and recommended to use <tt class=
+ "LITERAL">block</tt>.
+ </p>
+ <p>
+ Forwarding the source address of the request may make sense
+ in some multi-user setups but is also a privacy risk.
+ </p>
+ </dd>
+ <dt>
+ Example usage:
+ </dt>
+ <dd>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
++change-x-forwarded-for{block}
</pre>
- </td>
- </tr>
- </table>
-
- <p><a name="FILTER-FRAMESET-BORDERS" id=
- "FILTER-FRAMESET-BORDERS"></a></p>
+ </td>
+ </tr>
+ </table>
+ </dd>
+ </dl>
+ </div>
+ </div>
+ <div class="SECT3">
+ <h4 class="SECT3">
+ <a name="CLIENT-HEADER-FILTER">8.5.4. client-header-filter</a>
+ </h4>
+ <div class="VARIABLELIST">
+ <dl>
+ <dt>
+ Typical use:
+ </dt>
+ <dd>
+ <p>
+ Rewrite or remove single client headers.
+ </p>
+ </dd>
+ <dt>
+ Effect:
+ </dt>
+ <dd>
+ <p>
+ All client headers to which this action applies are
+ filtered on-the-fly through the specified regular
+ expression based substitutions.
+ </p>
+ </dd>
+ <dt>
+ Type:
+ </dt>
+ <dd>
+ <p>
+ Multi-value.
+ </p>
+ </dd>
+ <dt>
+ Parameter:
+ </dt>
+ <dd>
+ <p>
+ The name of a client-header filter, as defined in one of
+ the <a href="filter-file.html">filter files</a>.
+ </p>
+ </dd>
+ <dt>
+ Notes:
+ </dt>
+ <dd>
+ <p>
+ Client-header filters are applied to each header on its
+ own, not to all at once. This makes it easier to diagnose
+ problems, but on the downside you can't write filters that
+ only change header x if header y's value is z. You can do
+ that by using tags though.
+ </p>
+ <p>
+ Client-header filters are executed after the other header
+ actions have finished and use their output as input.
+ </p>
+ <p>
+ If the request URI gets changed, <span class=
+ "APPLICATION">Privoxy</span> will detect that and use the
+ new one. This can be used to rewrite the request
+ destination behind the client's back, for example to
+ specify a Tor exit relay for certain requests.
+ </p>
+ <p>
+ Please refer to the <a href="filter-file.html">filter file
+ chapter</a> to learn which client-header filters are
+ available by default, and how to create your own.
+ </p>
+ </dd>
+ <dt>
+ Example usage (section):
+ </dt>
+ <dd>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
+# Hide Tor exit notation in Host and Referer Headers
+{+client-header-filter{hide-tor-exit-notation}}
+/
- <table border="0" bgcolor="#E0E0E0" width="90%">
- <tr>
- <td>
- <pre class="SCREEN">
-+filter{frameset-borders} # Give frames a border and make them resizable.
</pre>
- </td>
- </tr>
- </table>
+ </td>
+ </tr>
+ </table>
+ </dd>
+ </dl>
+ </div>
+ </div>
+ <div class="SECT3">
+ <h4 class="SECT3">
+ <a name="CLIENT-HEADER-TAGGER">8.5.5. client-header-tagger</a>
+ </h4>
+ <div class="VARIABLELIST">
+ <dl>
+ <dt>
+ Typical use:
+ </dt>
+ <dd>
+ <p>
+ Block requests based on their headers.
+ </p>
+ </dd>
+ <dt>
+ Effect:
+ </dt>
+ <dd>
+ <p>
+ Client headers to which this action applies are filtered
+ on-the-fly through the specified regular expression based
+ substitutions, the result is used as tag.
+ </p>
+ </dd>
+ <dt>
+ Type:
+ </dt>
+ <dd>
+ <p>
+ Multi-value.
+ </p>
+ </dd>
+ <dt>
+ Parameter:
+ </dt>
+ <dd>
+ <p>
+ The name of a client-header tagger, as defined in one of
+ the <a href="filter-file.html">filter files</a>.
+ </p>
+ </dd>
+ <dt>
+ Notes:
+ </dt>
+ <dd>
+ <p>
+ Client-header taggers are applied to each header on its
+ own, and as the header isn't modified, each tagger <span
+ class="QUOTE">"sees"</span> the original.
+ </p>
+ <p>
+ Client-header taggers are the first actions that are
+ executed and their tags can be used to control every other
+ action.
+ </p>
+ </dd>
+ <dt>
+ Example usage (section):
+ </dt>
+ <dd>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
+# Tag every request with the User-Agent header
+{+client-header-tagger{user-agent}}
+/
- <p><a name="FILTER-IFRAMES" id="FILTER-IFRAMES"></a></p>
+# Tagging itself doesn't change the action
+# settings, sections with TAG patterns do:
+#
+# If it's a download agent, use a different forwarding proxy,
+# show the real User-Agent and make sure resume works.
+{+forward-override{forward-socks5 10.0.0.2:2222 .} \
+ -hide-if-modified-since \
+ -overwrite-last-modified \
+ -hide-user-agent \
+ -filter \
+ -deanimate-gifs \
+}
+TAG:^User-Agent: NetBSD-ftp/
+TAG:^User-Agent: Novell ZYPP Installer
+TAG:^User-Agent: RPM APT-HTTP/
+TAG:^User-Agent: fetch libfetch/
+TAG:^User-Agent: Ubuntu APT-HTTP/
+TAG:^User-Agent: MPlayer/
- <table border="0" bgcolor="#E0E0E0" width="90%">
- <tr>
- <td>
- <pre class="SCREEN">
-+filter{iframes} # Removes all detected iframes. Should only be enabled for individual sites.
</pre>
- </td>
- </tr>
- </table>
-
- <p><a name="FILTER-DEMORONIZER" id=
- "FILTER-DEMORONIZER"></a></p>
+ </td>
+ </tr>
+ </table>
- <table border="0" bgcolor="#E0E0E0" width="90%">
- <tr>
- <td>
- <pre class="SCREEN">
-+filter{demoronizer} # Fix MS's non-standard use of standard charsets.
-</pre>
- </td>
- </tr>
- </table>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
+# Tag all requests with the Range header set
+{+client-header-tagger{range-requests}}
+/
- <p><a name="FILTER-SHOCKWAVE-FLASH" id=
- "FILTER-SHOCKWAVE-FLASH"></a></p>
+# Disable filtering for the tagged requests.
+#
+# With filtering enabled Privoxy would remove the Range headers
+# to be able to filter the whole response. The downside is that
+# it prevents clients from resuming downloads or skipping over
+# parts of multimedia files.
+{-filter -deanimate-gifs}
+TAG:^RANGE-REQUEST$
- <table border="0" bgcolor="#E0E0E0" width="90%">
- <tr>
- <td>
- <pre class="SCREEN">
-+filter{shockwave-flash} # Kill embedded Shockwave Flash objects.
</pre>
- </td>
- </tr>
- </table>
-
- <p><a name="FILTER-QUICKTIME-KIOSKMODE" id=
- "FILTER-QUICKTIME-KIOSKMODE"></a></p>
+ </td>
+ </tr>
+ </table>
+ </dd>
+ </dl>
+ </div>
+ </div>
+ <div class="SECT3">
+ <h4 class="SECT3">
+ <a name="CONTENT-TYPE-OVERWRITE">8.5.6.
+ content-type-overwrite</a>
+ </h4>
+ <div class="VARIABLELIST">
+ <dl>
+ <dt>
+ Typical use:
+ </dt>
+ <dd>
+ <p>
+ Stop useless download menus from popping up, or change the
+ browser's rendering mode
+ </p>
+ </dd>
+ <dt>
+ Effect:
+ </dt>
+ <dd>
+ <p>
+ Replaces the <span class="QUOTE">"Content-Type:"</span>
+ HTTP server header.
+ </p>
+ </dd>
+ <dt>
+ Type:
+ </dt>
+ <dd>
+ <p>
+ Parameterized.
+ </p>
+ </dd>
+ <dt>
+ Parameter:
+ </dt>
+ <dd>
+ <p>
+ Any string.
+ </p>
+ </dd>
+ <dt>
+ Notes:
+ </dt>
+ <dd>
+ <p>
+ The <span class="QUOTE">"Content-Type:"</span> HTTP server
+ header is used by the browser to decide what to do with the
+ document. The value of this header can cause the browser to
+ open a download menu instead of displaying the document by
+ itself, even if the document's format is supported by the
+ browser.
+ </p>
+ <p>
+ The declared content type can also affect which rendering
+ mode the browser chooses. If XHTML is delivered as <span
+ class="QUOTE">"text/html"</span>, many browsers treat it as
+ yet another broken HTML document. If it is send as <span
+ class="QUOTE">"application/xml"</span>, browsers with XHTML
+ support will only display it, if the syntax is correct.
+ </p>
+ <p>
+ If you see a web site that proudly uses XHTML buttons, but
+ sets <span class="QUOTE">"Content-Type: text/html"</span>,
+ you can use <span class="APPLICATION">Privoxy</span> to
+ overwrite it with <span class=
+ "QUOTE">"application/xml"</span> and validate the web
+ master's claim inside your XHTML-supporting browser. If the
+ syntax is incorrect, the browser will complain loudly.
+ </p>
+ <p>
+ You can also go the opposite direction: if your browser
+ prints error messages instead of rendering a document
+ falsely declared as XHTML, you can overwrite the content
+ type with <span class="QUOTE">"text/html"</span> and have
+ it rendered as broken HTML document.
+ </p>
+ <p>
+ By default <tt class="LITERAL">content-type-overwrite</tt>
+ only replaces <span class="QUOTE">"Content-Type:"</span>
+ headers that look like some kind of text. If you want to
+ overwrite it unconditionally, you have to combine it with
+ <tt class="LITERAL"><a href=
+ "actions-file.html#FORCE-TEXT-MODE">force-text-mode</a></tt>.
+ This limitation exists for a reason, think twice before
+ circumventing it.
+ </p>
+ <p>
+ Most of the time it's easier to replace this action with a
+ custom <tt class="LITERAL"><a href=
+ "actions-file.html#SERVER-HEADER-FILTER">server-header
+ filter</a></tt>. It allows you to activate it for every
+ document of a certain site and it will still only replace
+ the content types you aimed at.
+ </p>
+ <p>
+ Of course you can apply <tt class=
+ "LITERAL">content-type-overwrite</tt> to a whole site and
+ then make URL based exceptions, but it's a lot more work to
+ get the same precision.
+ </p>
+ </dd>
+ <dt>
+ Example usage (sections):
+ </dt>
+ <dd>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
+# Check if www.example.net/ really uses valid XHTML
+{ +content-type-overwrite{application/xml} }
+www.example.net/
- <table border="0" bgcolor="#E0E0E0" width="90%">
- <tr>
- <td>
- <pre class="SCREEN">
-+filter{quicktime-kioskmode} # Make Quicktime movies saveable.
+# but leave the content type unmodified if the URL looks like a style sheet
+{-content-type-overwrite}
+www.example.net/.*\.css$
+www.example.net/.*style
</pre>
- </td>
- </tr>
- </table>
-
- <p><a name="FILTER-FUN" id="FILTER-FUN"></a></p>
+ </td>
+ </tr>
+ </table>
+ </dd>
+ </dl>
+ </div>
+ </div>
+ <div class="SECT3">
+ <h4 class="SECT3">
+ <a name="CRUNCH-CLIENT-HEADER">8.5.7. crunch-client-header</a>
+ </h4>
+ <div class="VARIABLELIST">
+ <dl>
+ <dt>
+ Typical use:
+ </dt>
+ <dd>
+ <p>
+ Remove a client header <span class=
+ "APPLICATION">Privoxy</span> has no dedicated action for.
+ </p>
+ </dd>
+ <dt>
+ Effect:
+ </dt>
+ <dd>
+ <p>
+ Deletes every header sent by the client that contains the
+ string the user supplied as parameter.
+ </p>
+ </dd>
+ <dt>
+ Type:
+ </dt>
+ <dd>
+ <p>
+ Parameterized.
+ </p>
+ </dd>
+ <dt>
+ Parameter:
+ </dt>
+ <dd>
+ <p>
+ Any string.
+ </p>
+ </dd>
+ <dt>
+ Notes:
+ </dt>
+ <dd>
+ <p>
+ This action allows you to block client headers for which no
+ dedicated <span class="APPLICATION">Privoxy</span> action
+ exists. <span class="APPLICATION">Privoxy</span> will
+ remove every client header that contains the string you
+ supplied as parameter.
+ </p>
+ <p>
+ Regular expressions are <span class="emphasis"><i class=
+ "EMPHASIS">not supported</i></span> and you can't use this
+ action to block different headers in the same request,
+ unless they contain the same string.
+ </p>
+ <p>
+ <tt class="LITERAL">crunch-client-header</tt> is only meant
+ for quick tests. If you have to block several different
+ headers, or only want to modify parts of them, you should
+ use a <tt class="LITERAL"><a href=
+ "actions-file.html#CLIENT-HEADER-FILTER">client-header
+ filter</a></tt>.
+ </p>
+ <div class="WARNING">
+ <table class="WARNING" border="1" width="90%">
+ <tr>
+ <td align="CENTER">
+ <b>Warning</b>
+ </td>
+ </tr>
+ <tr>
+ <td align="LEFT">
+ <p>
+ Don't block any header without understanding the
+ consequences.
+ </p>
+ </td>
+ </tr>
+ </table>
+ </div>
+ </dd>
+ <dt>
+ Example usage (section):
+ </dt>
+ <dd>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
+# Block the non-existent "Privacy-Violation:" client header
+{ +crunch-client-header{Privacy-Violation:} }
+/
- <table border="0" bgcolor="#E0E0E0" width="90%">
- <tr>
- <td>
- <pre class="SCREEN">
-+filter{fun} # Text replacements for subversive browsing fun!
</pre>
- </td>
- </tr>
- </table>
-
- <p><a name="FILTER-CRUDE-PARENTAL" id=
- "FILTER-CRUDE-PARENTAL"></a></p>
-
- <table border="0" bgcolor="#E0E0E0" width="90%">
- <tr>
- <td>
- <pre class="SCREEN">
-+filter{crude-parental} # Crude parental filtering. Note that this filter doesn't work reliably.
+ </td>
+ </tr>
+ </table>
+ </dd>
+ </dl>
+ </div>
+ </div>
+ <div class="SECT3">
+ <h4 class="SECT3">
+ <a name="CRUNCH-IF-NONE-MATCH">8.5.8. crunch-if-none-match</a>
+ </h4>
+ <div class="VARIABLELIST">
+ <dl>
+ <dt>
+ Typical use:
+ </dt>
+ <dd>
+ <p>
+ Prevent yet another way to track the user's steps between
+ sessions.
+ </p>
+ </dd>
+ <dt>
+ Effect:
+ </dt>
+ <dd>
+ <p>
+ Deletes the <span class="QUOTE">"If-None-Match:"</span>
+ HTTP client header.
+ </p>
+ </dd>
+ <dt>
+ Type:
+ </dt>
+ <dd>
+ <p>
+ Boolean.
+ </p>
+ </dd>
+ <dt>
+ Parameter:
+ </dt>
+ <dd>
+ <p>
+ N/A
+ </p>
+ </dd>
+ <dt>
+ Notes:
+ </dt>
+ <dd>
+ <p>
+ Removing the <span class="QUOTE">"If-None-Match:"</span>
+ HTTP client header is useful for filter testing, where you
+ want to force a real reload instead of getting status code
+ <span class="QUOTE">"304"</span> which would cause the
+ browser to use a cached copy of the page.
+ </p>
+ <p>
+ It is also useful to make sure the header isn't used as a
+ cookie replacement (unlikely but possible).
+ </p>
+ <p>
+ Blocking the <span class="QUOTE">"If-None-Match:"</span>
+ header shouldn't cause any caching problems, as long as the
+ <span class="QUOTE">"If-Modified-Since:"</span> header
+ isn't blocked or missing as well.
+ </p>
+ <p>
+ It is recommended to use this action together with <tt
+ class="LITERAL"><a href=
+ "actions-file.html#HIDE-IF-MODIFIED-SINCE">hide-if-modified-since</a></tt>
+ and <tt class="LITERAL"><a href=
+ "actions-file.html#OVERWRITE-LAST-MODIFIED">overwrite-last-modified</a></tt>.
+ </p>
+ </dd>
+ <dt>
+ Example usage (section):
+ </dt>
+ <dd>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
+# Let the browser revalidate cached documents but don't
+# allow the server to use the revalidation headers for user tracking.
+{+hide-if-modified-since{-60} \
+ +overwrite-last-modified{randomize} \
+ +crunch-if-none-match}
+/
</pre>
- </td>
- </tr>
- </table>
-
- <p><a name="FILTER-IE-EXPLOITS" id=
- "FILTER-IE-EXPLOITS"></a></p>
-
- <table border="0" bgcolor="#E0E0E0" width="90%">
- <tr>
- <td>
- <pre class="SCREEN">
-+filter{ie-exploits} # Disable some known Internet Explorer bug exploits.
+ </td>
+ </tr>
+ </table>
+ </dd>
+ </dl>
+ </div>
+ </div>
+ <div class="SECT3">
+ <h4 class="SECT3">
+ <a name="CRUNCH-INCOMING-COOKIES">8.5.9.
+ crunch-incoming-cookies</a>
+ </h4>
+ <div class="VARIABLELIST">
+ <dl>
+ <dt>
+ Typical use:
+ </dt>
+ <dd>
+ <p>
+ Prevent the web server from setting HTTP cookies on your
+ system
+ </p>
+ </dd>
+ <dt>
+ Effect:
+ </dt>
+ <dd>
+ <p>
+ Deletes any <span class="QUOTE">"Set-Cookie:"</span> HTTP
+ headers from server replies.
+ </p>
+ </dd>
+ <dt>
+ Type:
+ </dt>
+ <dd>
+ <p>
+ Boolean.
+ </p>
+ </dd>
+ <dt>
+ Parameter:
+ </dt>
+ <dd>
+ <p>
+ N/A
+ </p>
+ </dd>
+ <dt>
+ Notes:
+ </dt>
+ <dd>
+ <p>
+ This action is only concerned with <span class=
+ "emphasis"><i class="EMPHASIS">incoming</i></span> HTTP
+ cookies. For <span class="emphasis"><i class=
+ "EMPHASIS">outgoing</i></span> HTTP cookies, use <tt class=
+ "LITERAL"><a href=
+ "actions-file.html#CRUNCH-OUTGOING-COOKIES">crunch-outgoing-cookies</a></tt>.
+ Use <span class="emphasis"><i class=
+ "EMPHASIS">both</i></span> to disable HTTP cookies
+ completely.
+ </p>
+ <p>
+ It makes <span class="emphasis"><i class="EMPHASIS">no
+ sense at all</i></span> to use this action in conjunction
+ with the <tt class="LITERAL"><a href=
+ "actions-file.html#SESSION-COOKIES-ONLY">session-cookies-only</a></tt>
+ action, since it would prevent the session cookies from
+ being set. See also <tt class="LITERAL"><a href=
+ "actions-file.html#FILTER-CONTENT-COOKIES">filter-content-cookies</a></tt>.
+ </p>
+ </dd>
+ <dt>
+ Example usage:
+ </dt>
+ <dd>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
++crunch-incoming-cookies
</pre>
- </td>
- </tr>
- </table>
-
- <p><a name="FILTER-SITE-SPECIFICS" id=
- "FILTER-SITE-SPECIFICS"></a></p>
-
- <table border="0" bgcolor="#E0E0E0" width="90%">
- <tr>
- <td>
- <pre class="SCREEN">
-+filter{site-specifics} # Cure for site-specific problems. Don't apply generally!
+ </td>
+ </tr>
+ </table>
+ </dd>
+ </dl>
+ </div>
+ </div>
+ <div class="SECT3">
+ <h4 class="SECT3">
+ <a name="CRUNCH-SERVER-HEADER">8.5.10. crunch-server-header</a>
+ </h4>
+ <div class="VARIABLELIST">
+ <dl>
+ <dt>
+ Typical use:
+ </dt>
+ <dd>
+ <p>
+ Remove a server header <span class=
+ "APPLICATION">Privoxy</span> has no dedicated action for.
+ </p>
+ </dd>
+ <dt>
+ Effect:
+ </dt>
+ <dd>
+ <p>
+ Deletes every header sent by the server that contains the
+ string the user supplied as parameter.
+ </p>
+ </dd>
+ <dt>
+ Type:
+ </dt>
+ <dd>
+ <p>
+ Parameterized.
+ </p>
+ </dd>
+ <dt>
+ Parameter:
+ </dt>
+ <dd>
+ <p>
+ Any string.
+ </p>
+ </dd>
+ <dt>
+ Notes:
+ </dt>
+ <dd>
+ <p>
+ This action allows you to block server headers for which no
+ dedicated <span class="APPLICATION">Privoxy</span> action
+ exists. <span class="APPLICATION">Privoxy</span> will
+ remove every server header that contains the string you
+ supplied as parameter.
+ </p>
+ <p>
+ Regular expressions are <span class="emphasis"><i class=
+ "EMPHASIS">not supported</i></span> and you can't use this
+ action to block different headers in the same request,
+ unless they contain the same string.
+ </p>
+ <p>
+ <tt class="LITERAL">crunch-server-header</tt> is only meant
+ for quick tests. If you have to block several different
+ headers, or only want to modify parts of them, you should
+ use a custom <tt class="LITERAL"><a href=
+ "actions-file.html#SERVER-HEADER-FILTER">server-header
+ filter</a></tt>.
+ </p>
+ <div class="WARNING">
+ <table class="WARNING" border="1" width="90%">
+ <tr>
+ <td align="CENTER">
+ <b>Warning</b>
+ </td>
+ </tr>
+ <tr>
+ <td align="LEFT">
+ <p>
+ Don't block any header without understanding the
+ consequences.
+ </p>
+ </td>
+ </tr>
+ </table>
+ </div>
+ </dd>
+ <dt>
+ Example usage (section):
+ </dt>
+ <dd>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
+# Crunch server headers that try to prevent caching
+{ +crunch-server-header{no-cache} }
+/
</pre>
- </td>
- </tr>
- </table>
-
- <p><a name="FILTER-NO-PING" id="FILTER-NO-PING"></a></p>
-
- <table border="0" bgcolor="#E0E0E0" width="90%">
- <tr>
- <td>
- <pre class="SCREEN">
-+filter{no-ping} # Removes non-standard ping attributes in <a> and <area> tags.
+ </td>
+ </tr>
+ </table>
+ </dd>
+ </dl>
+ </div>
+ </div>
+ <div class="SECT3">
+ <h4 class="SECT3">
+ <a name="CRUNCH-OUTGOING-COOKIES">8.5.11.
+ crunch-outgoing-cookies</a>
+ </h4>
+ <div class="VARIABLELIST">
+ <dl>
+ <dt>
+ Typical use:
+ </dt>
+ <dd>
+ <p>
+ Prevent the web server from reading any HTTP cookies from
+ your system
+ </p>
+ </dd>
+ <dt>
+ Effect:
+ </dt>
+ <dd>
+ <p>
+ Deletes any <span class="QUOTE">"Cookie:"</span> HTTP
+ headers from client requests.
+ </p>
+ </dd>
+ <dt>
+ Type:
+ </dt>
+ <dd>
+ <p>
+ Boolean.
+ </p>
+ </dd>
+ <dt>
+ Parameter:
+ </dt>
+ <dd>
+ <p>
+ N/A
+ </p>
+ </dd>
+ <dt>
+ Notes:
+ </dt>
+ <dd>
+ <p>
+ This action is only concerned with <span class=
+ "emphasis"><i class="EMPHASIS">outgoing</i></span> HTTP
+ cookies. For <span class="emphasis"><i class=
+ "EMPHASIS">incoming</i></span> HTTP cookies, use <tt class=
+ "LITERAL"><a href=
+ "actions-file.html#CRUNCH-INCOMING-COOKIES">crunch-incoming-cookies</a></tt>.
+ Use <span class="emphasis"><i class=
+ "EMPHASIS">both</i></span> to disable HTTP cookies
+ completely.
+ </p>
+ <p>
+ It makes <span class="emphasis"><i class="EMPHASIS">no
+ sense at all</i></span> to use this action in conjunction
+ with the <tt class="LITERAL"><a href=
+ "actions-file.html#SESSION-COOKIES-ONLY">session-cookies-only</a></tt>
+ action, since it would prevent the session cookies from
+ being read.
+ </p>
+ </dd>
+ <dt>
+ Example usage:
+ </dt>
+ <dd>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
++crunch-outgoing-cookies
</pre>
- </td>
- </tr>
- </table>
-
- <p><a name="FILTER-GOOGLE" id="FILTER-GOOGLE"></a></p>
-
- <table border="0" bgcolor="#E0E0E0" width="90%">
- <tr>
- <td>
- <pre class="SCREEN">
-+filter{google} # CSS-based block for Google text ads. Also removes a width limitation and the toolbar advertisement.
+ </td>
+ </tr>
+ </table>
+ </dd>
+ </dl>
+ </div>
+ </div>
+ <div class="SECT3">
+ <h4 class="SECT3">
+ <a name="DEANIMATE-GIFS">8.5.12. deanimate-gifs</a>
+ </h4>
+ <div class="VARIABLELIST">
+ <dl>
+ <dt>
+ Typical use:
+ </dt>
+ <dd>
+ <p>
+ Stop those annoying, distracting animated GIF images.
+ </p>
+ </dd>
+ <dt>
+ Effect:
+ </dt>
+ <dd>
+ <p>
+ De-animate GIF animations, i.e. reduce them to their first
+ or last image.
+ </p>
+ </dd>
+ <dt>
+ Type:
+ </dt>
+ <dd>
+ <p>
+ Parameterized.
+ </p>
+ </dd>
+ <dt>
+ Parameter:
+ </dt>
+ <dd>
+ <p>
+ <span class="QUOTE">"last"</span> or <span class=
+ "QUOTE">"first"</span>
+ </p>
+ </dd>
+ <dt>
+ Notes:
+ </dt>
+ <dd>
+ <p>
+ This will also shrink the images considerably (in bytes,
+ not pixels!). If the option <span class=
+ "QUOTE">"first"</span> is given, the first frame of the
+ animation is used as the replacement. If <span class=
+ "QUOTE">"last"</span> 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).
+ </p>
+ <p>
+ 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.
+ </p>
+ </dd>
+ <dt>
+ Example usage:
+ </dt>
+ <dd>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
++deanimate-gifs{last}
</pre>
- </td>
- </tr>
- </table>
-
- <p><a name="FILTER-YAHOO" id="FILTER-YAHOO"></a></p>
-
- <table border="0" bgcolor="#E0E0E0" width="90%">
- <tr>
- <td>
- <pre class="SCREEN">
-+filter{yahoo} # CSS-based block for Yahoo text ads. Also removes a width limitation.
+ </td>
+ </tr>
+ </table>
+ </dd>
+ </dl>
+ </div>
+ </div>
+ <div class="SECT3">
+ <h4 class="SECT3">
+ <a name="DOWNGRADE-HTTP-VERSION">8.5.13.
+ downgrade-http-version</a>
+ </h4>
+ <div class="VARIABLELIST">
+ <dl>
+ <dt>
+ Typical use:
+ </dt>
+ <dd>
+ <p>
+ Work around (very rare) problems with HTTP/1.1
+ </p>
+ </dd>
+ <dt>
+ Effect:
+ </dt>
+ <dd>
+ <p>
+ Downgrades HTTP/1.1 client requests and server replies to
+ HTTP/1.0.
+ </p>
+ </dd>
+ <dt>
+ Type:
+ </dt>
+ <dd>
+ <p>
+ Boolean.
+ </p>
+ </dd>
+ <dt>
+ Parameter:
+ </dt>
+ <dd>
+ <p>
+ N/A
+ </p>
+ </dd>
+ <dt>
+ Notes:
+ </dt>
+ <dd>
+ <p>
+ This is a left-over from the time when <span class=
+ "APPLICATION">Privoxy</span> 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.
+ </p>
+ <p>
+ Note that enabling this action is only a workaround. It
+ should not be enabled for sites that work without it. While
+ it shouldn't break any pages, it has an (usually negative)
+ performance impact.
+ </p>
+ <p>
+ If you come across a site where enabling this action helps,
+ please report it, so the cause of the problem can be
+ analyzed. If the problem turns out to be caused by a bug in
+ <span class="APPLICATION">Privoxy</span> it should be fixed
+ so the following release works without the work around.
+ </p>
+ </dd>
+ <dt>
+ Example usage (section):
+ </dt>
+ <dd>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
+{+downgrade-http-version}
+problem-host.example.com
</pre>
- </td>
- </tr>
- </table>
-
- <p><a name="FILTER-MSN" id="FILTER-MSN"></a></p>
-
- <table border="0" bgcolor="#E0E0E0" width="90%">
- <tr>
- <td>
- <pre class="SCREEN">
-+filter{msn} # CSS-based block for MSN text ads. Also removes tracking URLs and a width limitation.
+ </td>
+ </tr>
+ </table>
+ </dd>
+ </dl>
+ </div>
+ </div>
+ <div class="SECT3">
+ <h4 class="SECT3">
+ <a name="EXTERNAL-FILTER">8.5.14. external-filter</a>
+ </h4>
+ <div class="VARIABLELIST">
+ <dl>
+ <dt>
+ Typical use:
+ </dt>
+ <dd>
+ <p>
+ Modify content using a programming language of your choice.
+ </p>
+ </dd>
+ <dt>
+ Effect:
+ </dt>
+ <dd>
+ <p>
+ All instances of text-based type, most notably HTML and
+ JavaScript, to which this action applies, can be filtered
+ on-the-fly through the specified external filter. By
+ default plain text documents are exempted from filtering,
+ because web servers often use the <tt class=
+ "LITERAL">text/plain</tt> MIME type for all files whose
+ type they don't know.)
+ </p>
+ </dd>
+ <dt>
+ Type:
+ </dt>
+ <dd>
+ <p>
+ Multi-value.
+ </p>
+ </dd>
+ <dt>
+ Parameter:
+ </dt>
+ <dd>
+ <p>
+ The name of an external content filter, as defined in the
+ <a href="filter-file.html">filter file</a>. External
+ filters can be defined in one or more files as defined by
+ the <tt class="LITERAL"><a href=
+ "config.html#FILTERFILE">filterfile</a></tt> option in the
+ <a href="config.html">config file</a>.
+ </p>
+ <p>
+ When used in its negative form, and without parameters,
+ <span class="emphasis"><i class="EMPHASIS">all</i></span>
+ filtering with external filters is completely disabled.
+ </p>
+ </dd>
+ <dt>
+ Notes:
+ </dt>
+ <dd>
+ <p>
+ External filters are scripts or programs that can modify
+ the content in case common <tt class="LITERAL"><a href=
+ "actions-file.html#FILTER">filters</a></tt> aren't powerful
+ enough. With the exception that this action doesn't use
+ pcrs-based filters, the notes in the <tt class="LITERAL"><a
+ href="actions-file.html#FILTER">filter</a></tt> section
+ apply.
+ </p>
+ <div class="WARNING">
+ <table class="WARNING" border="1" width="90%">
+ <tr>
+ <td align="CENTER">
+ <b>Warning</b>
+ </td>
+ </tr>
+ <tr>
+ <td align="LEFT">
+ <p>
+ Currently external filters are executed with <span
+ class="APPLICATION">Privoxy</span>'s privileges.
+ Only use external filters you understand and trust.
+ </p>
+ </td>
+ </tr>
+ </table>
+ </div>
+ <p>
+ This feature is experimental, the <tt class="LITERAL"><a
+ href=
+ "filter-file.html#EXTERNAL-FILTER-SYNTAX">syntax</a></tt>
+ may change in the future.
+ </p>
+ </dd>
+ <dt>
+ Example usage:
+ </dt>
+ <dd>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
++external-filter{fancy-filter}
</pre>
- </td>
- </tr>
- </table>
-
- <p><a name="FILTER-BLOGSPOT" id="FILTER-BLOGSPOT"></a></p>
+ </td>
+ </tr>
+ </table>
+ </dd>
+ </dl>
+ </div>
+ </div>
+ <div class="SECT3">
+ <h4 class="SECT3">
+ <a name="FAST-REDIRECTS">8.5.15. fast-redirects</a>
+ </h4>
+ <div class="VARIABLELIST">
+ <dl>
+ <dt>
+ Typical use:
+ </dt>
+ <dd>
+ <p>
+ Fool some click-tracking scripts and speed up indirect
+ links.
+ </p>
+ </dd>
+ <dt>
+ Effect:
+ </dt>
+ <dd>
+ <p>
+ Detects redirection URLs and redirects the browser without
+ contacting the redirection server first.
+ </p>
+ </dd>
+ <dt>
+ Type:
+ </dt>
+ <dd>
+ <p>
+ Parameterized.
+ </p>
+ </dd>
+ <dt>
+ Parameter:
+ </dt>
+ <dd>
+ <ul>
+ <li>
+ <p>
+ <span class="QUOTE">"simple-check"</span> to just
+ search for the string <span class=
+ "QUOTE">"http://"</span> to detect redirection URLs.
+ </p>
+ </li>
+ <li>
+ <p>
+ <span class="QUOTE">"check-decoded-url"</span> to
+ decode URLs (if necessary) before searching for
+ redirection URLs.
+ </p>
+ </li>
+ </ul>
+ </dd>
+ <dt>
+ Notes:
+ </dt>
+ <dd>
+ <p>
+ 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: <span class=
+ "QUOTE">"http://www.example.org/click-tracker.cgi?target=http%3a//www.example.net/"</span>.
+ </p>
+ <p>
+ Sometimes, there are even multiple consecutive redirects
+ encoded in the URL. These redirections via scripts make
+ your web browsing more traceable, since the server from
+ which you follow such a link can see where you go to. Apart
+ from that, valuable bandwidth and time is wasted, while
+ your browser asks the server for one redirect after the
+ other. Plus, it feeds the advertisers.
+ </p>
+ <p>
+ This feature is currently not very smart and is scheduled
+ for improvement. If it is enabled by default, you will have
+ to create some exceptions to this action. It can lead to
+ failures in several ways:
+ </p>
+ <p>
+ Not every URLs with other URLs as parameters is evil. Some
+ sites offer a real service that requires this information
+ to work. For example a validation service needs to know,
+ which document to validate. <tt class=
+ "LITERAL">fast-redirects</tt> assumes that every URL
+ parameter that looks like another URL is a redirection
+ target, and will always redirect to the last one. Most of
+ the time the assumption is correct, but if it isn't, the
+ user gets redirected anyway.
+ </p>
+ <p>
+ Another failure occurs if the URL contains other parameters
+ after the URL parameter. The URL: <span class=
+ "QUOTE">"http://www.example.org/?redirect=http%3a//www.example.net/&foo=bar"</span>.
+ contains the redirection URL <span class=
+ "QUOTE">"http://www.example.net/"</span>, followed by
+ another parameter. <tt class="LITERAL">fast-redirects</tt>
+ doesn't know that and will cause a redirect to <span class=
+ "QUOTE">"http://www.example.net/&foo=bar"</span>.
+ Depending on the target server configuration, the parameter
+ will be silently ignored or lead to a <span class=
+ "QUOTE">"page not found"</span> error. You can prevent this
+ problem by first using the <tt class="LITERAL"><a href=
+ "actions-file.html#REDIRECT">redirect</a></tt> action to
+ remove the last part of the URL, but it requires a little
+ effort.
+ </p>
+ <p>
+ To detect a redirection URL, <tt class=
+ "LITERAL">fast-redirects</tt> only looks for the string
+ <span class="QUOTE">"http://"</span>, either in plain text
+ (invalid but often used) or encoded as <span class=
+ "QUOTE">"http%3a//"</span>. Some sites use their own URL
+ encoding scheme, encrypt the address of the target server
+ or replace it with a database id. In theses cases <tt
+ class="LITERAL">fast-redirects</tt> is fooled and the
+ request reaches the redirection server where it probably
+ gets logged.
+ </p>
+ </dd>
+ <dt>
+ Example usage:
+ </dt>
+ <dd>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
+ { +fast-redirects{simple-check} }
+ one.example.com
- <table border="0" bgcolor="#E0E0E0" width="90%">
- <tr>
- <td>
- <pre class="SCREEN">
-+filter{blogspot} # Cleans up some Blogspot blogs. Read the fine print before using this.
+ { +fast-redirects{check-decoded-url} }
+ another.example.com/testing
</pre>
- </td>
- </tr>
- </table>
- </dd>
- </dl>
+ </td>
+ </tr>
+ </table>
+ </dd>
+ </dl>
+ </div>
</div>
- </div>
-
- <div class="SECT3">
- <h4 class="SECT3"><a name="FORCE-TEXT-MODE" id=
- "FORCE-TEXT-MODE">8.5.17. force-text-mode</a></h4>
-
- <div class="VARIABLELIST">
- <dl>
- <dt>Typical use:</dt>
-
- <dd>
- <p>Force <span class="APPLICATION">Privoxy</span> to treat a
- document as if it was in some kind of <span class=
- "emphasis"><i class="EMPHASIS">text</i></span> format.</p>
- </dd>
-
- <dt>Effect:</dt>
-
- <dd>
- <p>Declares a document as text, even if the <span class=
- "QUOTE">"Content-Type:"</span> isn't detected as such.</p>
- </dd>
-
- <dt>Type:</dt>
-
- <dd>
- <p>Boolean.</p>
- </dd>
-
- <dt>Parameter:</dt>
-
- <dd>
- <p>N/A</p>
- </dd>
-
- <dt>Notes:</dt>
+ <div class="SECT3">
+ <h4 class="SECT3">
+ <a name="FILTER">8.5.16. filter</a>
+ </h4>
+ <div class="VARIABLELIST">
+ <dl>
+ <dt>
+ Typical use:
+ </dt>
+ <dd>
+ <p>
+ Get rid of HTML and JavaScript annoyances, banner
+ advertisements (by size), do fun text replacements, add
+ personalized effects, etc.
+ </p>
+ </dd>
+ <dt>
+ Effect:
+ </dt>
+ <dd>
+ <p>
+ All instances of text-based type, most notably HTML and
+ JavaScript, to which this action applies, can be filtered
+ on-the-fly through the specified regular expression based
+ substitutions. (Note: as of version 3.0.3 plain text
+ documents are exempted from filtering, because web servers
+ often use the <tt class="LITERAL">text/plain</tt> MIME type
+ for all files whose type they don't know.)
+ </p>
+ </dd>
+ <dt>
+ Type:
+ </dt>
+ <dd>
+ <p>
+ Multi-value.
+ </p>
+ </dd>
+ <dt>
+ Parameter:
+ </dt>
+ <dd>
+ <p>
+ The name of a content filter, as defined in the <a href=
+ "filter-file.html">filter file</a>. Filters can be defined
+ in one or more files as defined by the <tt class=
+ "LITERAL"><a href=
+ "config.html#FILTERFILE">filterfile</a></tt> option in the
+ <a href="config.html">config file</a>. <tt class=
+ "FILENAME">default.filter</tt> is the collection of filters
+ supplied by the developers. Locally defined filters should
+ go in their own file, such as <tt class=
+ "FILENAME">user.filter</tt>.
+ </p>
+ <p>
+ When used in its negative form, and without parameters,
+ <span class="emphasis"><i class="EMPHASIS">all</i></span>
+ filtering is completely disabled.
+ </p>
+ </dd>
+ <dt>
+ Notes:
+ </dt>
+ <dd>
+ <p>
+ For your convenience, there are a number of pre-defined
+ filters available in the distribution filter file that you
+ can use. See the examples below for a list.
+ </p>
+ <p>
+ 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. (The
+ total time until the page is completely rendered doesn't
+ change much, but it may be perceived as slower since the
+ page is not incrementally displayed.) This effect will be
+ more noticeable on slower connections.
+ </p>
+ <p>
+ <span class="QUOTE">"Rolling your own"</span> filters
+ requires a knowledge of <a href=
+ "http://en.wikipedia.org/wiki/Regular_expressions" target=
+ "_top"><span class="QUOTE">"Regular Expressions"</span></a>
+ and <a href="http://en.wikipedia.org/wiki/Html" target=
+ "_top"><span class="QUOTE">"HTML"</span></a>. This is very
+ powerful feature, and potentially very intrusive. Filters
+ should be used with caution, and where an equivalent <span
+ class="QUOTE">"action"</span> is not available.
+ </p>
+ <p>
+ The amount of data that can be filtered is limited to the
+ <tt class="LITERAL"><a href=
+ "config.html#BUFFER-LIMIT">buffer-limit</a></tt> option in
+ the main <a href="config.html">config file</a>. The default
+ is 4096 KB (4 Megs). Once this limit is exceeded, the
+ buffered data, and all pending data, is passed through
+ unfiltered.
+ </p>
+ <p>
+ Inappropriate MIME types, such as zipped files, are not
+ filtered at all. (Again, only text-based types except plain
+ text). Encrypted SSL data (from HTTPS servers) cannot be
+ filtered either, since this would violate the integrity of
+ the secure transaction. In some situations it might be
+ necessary to protect certain text, like source code, from
+ filtering by defining appropriate <tt class=
+ "LITERAL">-filter</tt> exceptions.
+ </p>
+ <p>
+ Compressed content can't be filtered either, but if <span
+ class="APPLICATION">Privoxy</span> is compiled with zlib
+ support and a supported compression algorithm is used (gzip
+ or deflate), <span class="APPLICATION">Privoxy</span> can
+ first decompress the content and then filter it.
+ </p>
+ <p>
+ If you use a <span class="APPLICATION">Privoxy</span>
+ version without zlib support, but want filtering to work on
+ as much documents as possible, even those that would
+ normally be sent compressed, you must use the <tt class=
+ "LITERAL"><a href=
+ "actions-file.html#PREVENT-COMPRESSION">prevent-compression</a></tt>
+ action in conjunction with <tt class="LITERAL">filter</tt>.
+ </p>
+ <p>
+ Content filtering can achieve some of the same effects as
+ the <tt class="LITERAL"><a href=
+ "actions-file.html#BLOCK">block</a></tt> action, i.e. it
+ can be used to block ads and banners. But the mechanism
+ works quite differently. One effective use, is to block ad
+ banners based on their size (see below), since many of
+ these seem to be somewhat standardized.
+ </p>
+ <p>
+ <a href="contact.html">Feedback</a> with suggestions for
+ new or improved filters is particularly welcome!
+ </p>
+ <p>
+ The below list has only the names and a one-line
+ description of each predefined filter. There are <a href=
+ "filter-file.html#PREDEFINED-FILTERS">more verbose
+ explanations</a> of what these filters do in the <a href=
+ "filter-file.html">filter file chapter</a>.
+ </p>
+ </dd>
+ <dt>
+ Example usage (with filters from the distribution <tt class=
+ "FILENAME">default.filter</tt> file). See <a href=
+ "filter-file.html#PREDEFINED-FILTERS">the Predefined Filters
+ section</a> for more explanation on each:
+ </dt>
+ <dd>
+ <p>
+ <a name="FILTER-JS-ANNOYANCES"></a>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
++filter{js-annoyances} # Get rid of particularly annoying JavaScript abuse.
+</pre>
+ </td>
+ </tr>
+ </table>
- <dd>
- <p>As explained <tt class="LITERAL"><a href=
- "actions-file.html#FILTER">above</a></tt>, <span class=
- "APPLICATION">Privoxy</span> tries to only filter files that
- are in some kind of text format. The same restrictions apply to
- <tt class="LITERAL"><a href=
- "actions-file.html#CONTENT-TYPE-OVERWRITE">content-type-overwrite</a></tt>.
- <tt class="LITERAL">force-text-mode</tt> declares a document as
- text, without looking at the <span class=
- "QUOTE">"Content-Type:"</span> first.</p>
+ <p>
+ <a name="FILTER-JS-EVENTS"></a>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
++filter{js-events} # Kill JavaScript event bindings and timers (Radically destructive! Only for extra nasty sites).
+</pre>
+ </td>
+ </tr>
+ </table>
- <div class="WARNING">
- <table class="WARNING" border="1" width="90%">
+ <p>
+ <a name="FILTER-HTML-ANNOYANCES"></a>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
<tr>
- <td align="center"><b>Warning</b></td>
+ <td>
+<pre class="SCREEN">
++filter{html-annoyances} # Get rid of particularly annoying HTML abuse.
+</pre>
+ </td>
</tr>
+ </table>
+ <p>
+ <a name="FILTER-CONTENT-COOKIES"></a>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
<tr>
- <td align="left">
- <p>Think twice before activating this action. Filtering
- binary data with regular expressions can cause file
- damage.</p>
+ <td>
+<pre class="SCREEN">
++filter{content-cookies} # Kill cookies that come in the HTML or JS content.
+</pre>
</td>
</tr>
</table>
- </div>
- </dd>
-
- <dt>Example usage:</dt>
-
- <dd>
- <table border="0" bgcolor="#E0E0E0" width="90%">
- <tr>
- <td>
- <pre class="SCREEN">
-+force-text-mode
+ <p>
+ <a name="FILTER-REFRESH-TAGS"></a>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
++filter{refresh-tags} # Kill automatic refresh tags if refresh time is larger than 9 seconds.
</pre>
- </td>
- </tr>
- </table>
- </dd>
- </dl>
- </div>
- </div>
-
- <div class="SECT3">
- <h4 class="SECT3"><a name="FORWARD-OVERRIDE" id=
- "FORWARD-OVERRIDE">8.5.18. forward-override</a></h4>
-
- <div class="VARIABLELIST">
- <dl>
- <dt>Typical use:</dt>
+ </td>
+ </tr>
+ </table>
- <dd>
- <p>Change the forwarding settings based on User-Agent or
- request origin</p>
- </dd>
+ <p>
+ <a name="FILTER-UNSOLICITED-POPUPS"></a>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
++filter{unsolicited-popups} # Disable only unsolicited pop-up windows.
+</pre>
+ </td>
+ </tr>
+ </table>
- <dt>Effect:</dt>
+ <p>
+ <a name="FILTER-ALL-POPUPS"></a>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
++filter{all-popups} # Kill all popups in JavaScript and HTML.
+</pre>
+ </td>
+ </tr>
+ </table>
- <dd>
- <p>Overrules the forward directives in the configuration
- file.</p>
- </dd>
+ <p>
+ <a name="FILTER-IMG-REORDER"></a>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
++filter{img-reorder} # Reorder attributes in <img> tags to make the banners-by-* filters more effective.
+</pre>
+ </td>
+ </tr>
+ </table>
- <dt>Type:</dt>
+ <p>
+ <a name="FILTER-BANNERS-BY-SIZE"></a>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
++filter{banners-by-size} # Kill banners by size.
+</pre>
+ </td>
+ </tr>
+ </table>
- <dd>
- <p>Parameterized.</p>
- </dd>
+ <p>
+ <a name="FILTER-BANNERS-BY-LINK"></a>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
++filter{banners-by-link} # Kill banners by their links to known clicktrackers.
+</pre>
+ </td>
+ </tr>
+ </table>
- <dt>Parameter:</dt>
+ <p>
+ <a name="FILTER-WEBBUGS"></a>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
++filter{webbugs} # Squish WebBugs (1x1 invisible GIFs used for user tracking).
+</pre>
+ </td>
+ </tr>
+ </table>
- <dd>
- <ul>
- <li>
- <p><span class="QUOTE">"forward ."</span> to use a direct
- connection without any additional proxies.</p>
- </li>
+ <p>
+ <a name="FILTER-TINY-TEXTFORMS"></a>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
++filter{tiny-textforms} # Extend those tiny textareas up to 40x80 and kill the hard wrap.
+</pre>
+ </td>
+ </tr>
+ </table>
- <li>
- <p><span class="QUOTE">"forward 127.0.0.1:8123"</span> to
- use the HTTP proxy listening at 127.0.0.1 port 8123.</p>
- </li>
+ <p>
+ <a name="FILTER-JUMPING-WINDOWS"></a>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
++filter{jumping-windows} # Prevent windows from resizing and moving themselves.
+</pre>
+ </td>
+ </tr>
+ </table>
- <li>
- <p><span class="QUOTE">"forward-socks4a 127.0.0.1:9050
- ."</span> to use the socks4a proxy listening at 127.0.0.1
- port 9050. Replace <span class=
- "QUOTE">"forward-socks4a"</span> with <span class=
- "QUOTE">"forward-socks4"</span> to use a socks4 connection
- (with local DNS resolution) instead, use <span class=
- "QUOTE">"forward-socks5"</span> for socks5 connections
- (with remote DNS resolution).</p>
- </li>
+ <p>
+ <a name="FILTER-FRAMESET-BORDERS"></a>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
++filter{frameset-borders} # Give frames a border and make them resizable.
+</pre>
+ </td>
+ </tr>
+ </table>
- <li>
- <p><span class="QUOTE">"forward-socks4a 127.0.0.1:9050
- proxy.example.org:8000"</span> to use the socks4a proxy
- listening at 127.0.0.1 port 9050 to reach the HTTP proxy
- listening at proxy.example.org port 8000. Replace
- <span class="QUOTE">"forward-socks4a"</span> with
- <span class="QUOTE">"forward-socks4"</span> to use a socks4
- connection (with local DNS resolution) instead, use
- <span class="QUOTE">"forward-socks5"</span> for socks5
- connections (with remote DNS resolution).</p>
- </li>
+ <p>
+ <a name="FILTER-IFRAMES"></a>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
++filter{iframes} # Removes all detected iframes. Should only be enabled for individual sites.
+</pre>
+ </td>
+ </tr>
+ </table>
- <li>
- <p><span class="QUOTE">"forward-webserver
- 127.0.0.1:80"</span> to use the HTTP server listening at
- 127.0.0.1 port 80 without adjusting the request
- headers.</p>
+ <p>
+ <a name="FILTER-DEMORONIZER"></a>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
++filter{demoronizer} # Fix MS's non-standard use of standard charsets.
+</pre>
+ </td>
+ </tr>
+ </table>
- <p>This makes it more convenient to use Privoxy to make
- existing websites available as onion services as well.</p>
+ <p>
+ <a name="FILTER-SHOCKWAVE-FLASH"></a>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
++filter{shockwave-flash} # Kill embedded Shockwave Flash objects.
+</pre>
+ </td>
+ </tr>
+ </table>
- <p>Many websites serve content with hardcoded URLs and
- can't be easily adjusted to change the domain based on the
- one used by the client.</p>
+ <p>
+ <a name="FILTER-QUICKTIME-KIOSKMODE"></a>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
++filter{quicktime-kioskmode} # Make Quicktime movies saveable.
+</pre>
+ </td>
+ </tr>
+ </table>
- <p>Putting Privoxy between Tor and the webserver (or an
- stunnel that forwards to the webserver) allows to rewrite
- headers and content to make client and server happy at the
- same time.</p>
+ <p>
+ <a name="FILTER-FUN"></a>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
++filter{fun} # Text replacements for subversive browsing fun!
+</pre>
+ </td>
+ </tr>
+ </table>
- <p>Using Privoxy for webservers that are only reachable
- through onion addresses and whose location is supposed to
- be secret is not recommended and should not be necessary
- anyway.</p>
- </li>
- </ul>
- </dd>
+ <p>
+ <a name="FILTER-CRUDE-PARENTAL"></a>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
++filter{crude-parental} # Crude parental filtering. Note that this filter doesn't work reliably.
+</pre>
+ </td>
+ </tr>
+ </table>
- <dt>Notes:</dt>
+ <p>
+ <a name="FILTER-IE-EXPLOITS"></a>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
++filter{ie-exploits} # Disable some known Internet Explorer bug exploits.
+</pre>
+ </td>
+ </tr>
+ </table>
- <dd>
- <p>This action takes parameters similar to the <a href=
- "config.html#FORWARDING">forward</a> directives in the
- configuration file, but without the URL pattern. It can be used
- as replacement, but normally it's only used in cases where
- matching based on the request URL isn't sufficient.</p>
+ <p>
+ <a name="FILTER-SITE-SPECIFICS"></a>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
++filter{site-specifics} # Cure for site-specific problems. Don't apply generally!
+</pre>
+ </td>
+ </tr>
+ </table>
- <div class="WARNING">
- <table class="WARNING" border="1" width="90%">
+ <p>
+ <a name="FILTER-NO-PING"></a>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
<tr>
- <td align="center"><b>Warning</b></td>
+ <td>
+<pre class="SCREEN">
++filter{no-ping} # Removes non-standard ping attributes in <a> and <area> tags.
+</pre>
+ </td>
</tr>
+ </table>
+ <p>
+ <a name="FILTER-GOOGLE"></a>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
<tr>
- <td align="left">
- <p>Please read the description for the <a href=
- "config.html#FORWARDING">forward</a> directives before
- using this action. Forwarding to the wrong people will
- reduce your privacy and increase the chances of
- man-in-the-middle attacks.</p>
+ <td>
+<pre class="SCREEN">
++filter{google} # CSS-based block for Google text ads. Also removes a width limitation and the toolbar advertisement.
+</pre>
+ </td>
+ </tr>
+ </table>
- <p>If the ports are missing or invalid, default values
- will be used. This might change in the future and you
- shouldn't rely on it. Otherwise incorrect syntax causes
- Privoxy to exit. Due to design limitations, invalid
- parameter syntax isn't detected until the action is
- used the first time.</p>
+ <p>
+ <a name="FILTER-YAHOO"></a>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
++filter{yahoo} # CSS-based block for Yahoo text ads. Also removes a width limitation.
+</pre>
+ </td>
+ </tr>
+ </table>
- <p>Use the <a href=
- "http://config.privoxy.org/show-url-info" target=
- "_top">show-url-info CGI page</a> to verify that your
- forward settings do what you thought the do.</p>
+ <p>
+ <a name="FILTER-MSN"></a>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
++filter{msn} # CSS-based block for MSN text ads. Also removes tracking URLs and a width limitation.
+</pre>
</td>
</tr>
</table>
- </div>
- </dd>
- <dt>Example usage:</dt>
+ <p>
+ <a name="FILTER-BLOGSPOT"></a>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
++filter{blogspot} # Cleans up some Blogspot blogs. Read the fine print before using this.
+</pre>
+ </td>
+ </tr>
+ </table>
+ </dd>
+ </dl>
+ </div>
+ </div>
+ <div class="SECT3">
+ <h4 class="SECT3">
+ <a name="FORCE-TEXT-MODE">8.5.17. force-text-mode</a>
+ </h4>
+ <div class="VARIABLELIST">
+ <dl>
+ <dt>
+ Typical use:
+ </dt>
+ <dd>
+ <p>
+ Force <span class="APPLICATION">Privoxy</span> to treat a
+ document as if it was in some kind of <span class=
+ "emphasis"><i class="EMPHASIS">text</i></span> format.
+ </p>
+ </dd>
+ <dt>
+ Effect:
+ </dt>
+ <dd>
+ <p>
+ Declares a document as text, even if the <span class=
+ "QUOTE">"Content-Type:"</span> isn't detected as such.
+ </p>
+ </dd>
+ <dt>
+ Type:
+ </dt>
+ <dd>
+ <p>
+ Boolean.
+ </p>
+ </dd>
+ <dt>
+ Parameter:
+ </dt>
+ <dd>
+ <p>
+ N/A
+ </p>
+ </dd>
+ <dt>
+ Notes:
+ </dt>
+ <dd>
+ <p>
+ As explained <tt class="LITERAL"><a href=
+ "actions-file.html#FILTER">above</a></tt>, <span class=
+ "APPLICATION">Privoxy</span> tries to only filter files
+ that are in some kind of text format. The same restrictions
+ apply to <tt class="LITERAL"><a href=
+ "actions-file.html#CONTENT-TYPE-OVERWRITE">content-type-overwrite</a></tt>.
+ <tt class="LITERAL">force-text-mode</tt> declares a
+ document as text, without looking at the <span class=
+ "QUOTE">"Content-Type:"</span> first.
+ </p>
+ <div class="WARNING">
+ <table class="WARNING" border="1" width="90%">
+ <tr>
+ <td align="CENTER">
+ <b>Warning</b>
+ </td>
+ </tr>
+ <tr>
+ <td align="LEFT">
+ <p>
+ Think twice before activating this action.
+ Filtering binary data with regular expressions can
+ cause file damage.
+ </p>
+ </td>
+ </tr>
+ </table>
+ </div>
+ </dd>
+ <dt>
+ Example usage:
+ </dt>
+ <dd>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
++force-text-mode
- <dd>
- <table border="0" bgcolor="#E0E0E0" width="90%">
- <tr>
- <td>
- <pre class="SCREEN">
+</pre>
+ </td>
+ </tr>
+ </table>
+ </dd>
+ </dl>
+ </div>
+ </div>
+ <div class="SECT3">
+ <h4 class="SECT3">
+ <a name="FORWARD-OVERRIDE">8.5.18. forward-override</a>
+ </h4>
+ <div class="VARIABLELIST">
+ <dl>
+ <dt>
+ Typical use:
+ </dt>
+ <dd>
+ <p>
+ Change the forwarding settings based on User-Agent or
+ request origin
+ </p>
+ </dd>
+ <dt>
+ Effect:
+ </dt>
+ <dd>
+ <p>
+ Overrules the forward directives in the configuration file.
+ </p>
+ </dd>
+ <dt>
+ Type:
+ </dt>
+ <dd>
+ <p>
+ Parameterized.
+ </p>
+ </dd>
+ <dt>
+ Parameter:
+ </dt>
+ <dd>
+ <ul>
+ <li>
+ <p>
+ <span class="QUOTE">"forward ."</span> to use a direct
+ connection without any additional proxies.
+ </p>
+ </li>
+ <li>
+ <p>
+ <span class="QUOTE">"forward 127.0.0.1:8123"</span> to
+ use the HTTP proxy listening at 127.0.0.1 port 8123.
+ </p>
+ </li>
+ <li>
+ <p>
+ <span class="QUOTE">"forward-socks4a 127.0.0.1:9050
+ ."</span> to use the socks4a proxy listening at
+ 127.0.0.1 port 9050. Replace <span class=
+ "QUOTE">"forward-socks4a"</span> with <span class=
+ "QUOTE">"forward-socks4"</span> to use a socks4
+ connection (with local DNS resolution) instead, use
+ <span class="QUOTE">"forward-socks5"</span> for socks5
+ connections (with remote DNS resolution).
+ </p>
+ </li>
+ <li>
+ <p>
+ <span class="QUOTE">"forward-socks4a 127.0.0.1:9050
+ proxy.example.org:8000"</span> to use the socks4a proxy
+ listening at 127.0.0.1 port 9050 to reach the HTTP
+ proxy listening at proxy.example.org port 8000. Replace
+ <span class="QUOTE">"forward-socks4a"</span> with <span
+ class="QUOTE">"forward-socks4"</span> to use a socks4
+ connection (with local DNS resolution) instead, use
+ <span class="QUOTE">"forward-socks5"</span> for socks5
+ connections (with remote DNS resolution).
+ </p>
+ </li>
+ <li>
+ <p>
+ <span class="QUOTE">"forward-webserver
+ 127.0.0.1:80"</span> to use the HTTP server listening
+ at 127.0.0.1 port 80 without adjusting the request
+ headers.
+ </p>
+ <p>
+ This makes it more convenient to use Privoxy to make
+ existing websites available as onion services as well.
+ </p>
+ <p>
+ Many websites serve content with hardcoded URLs and
+ can't be easily adjusted to change the domain based on
+ the one used by the client.
+ </p>
+ <p>
+ Putting Privoxy between Tor and the webserver (or an
+ stunnel that forwards to the webserver) allows to
+ rewrite headers and content to make client and server
+ happy at the same time.
+ </p>
+ <p>
+ Using Privoxy for webservers that are only reachable
+ through onion addresses and whose location is supposed
+ to be secret is not recommended and should not be
+ necessary anyway.
+ </p>
+ </li>
+ </ul>
+ </dd>
+ <dt>
+ Notes:
+ </dt>
+ <dd>
+ <p>
+ This action takes parameters similar to the <a href=
+ "config.html#FORWARDING">forward</a> directives in the
+ configuration file, but without the URL pattern. It can be
+ used as replacement, but normally it's only used in cases
+ where matching based on the request URL isn't sufficient.
+ </p>
+ <div class="WARNING">
+ <table class="WARNING" border="1" width="90%">
+ <tr>
+ <td align="CENTER">
+ <b>Warning</b>
+ </td>
+ </tr>
+ <tr>
+ <td align="LEFT">
+ <p>
+ Please read the description for the <a href=
+ "config.html#FORWARDING">forward</a> directives
+ before using this action. Forwarding to the wrong
+ people will reduce your privacy and increase the
+ chances of man-in-the-middle attacks.
+ </p>
+ <p>
+ If the ports are missing or invalid, default values
+ will be used. This might change in the future and
+ you shouldn't rely on it. Otherwise incorrect
+ syntax causes Privoxy to exit. Due to design
+ limitations, invalid parameter syntax isn't
+ detected until the action is used the first time.
+ </p>
+ <p>
+ Use the <a href=
+ "http://config.privoxy.org/show-url-info" target=
+ "_top">show-url-info CGI page</a> to verify that
+ your forward settings do what you thought the do.
+ </p>
+ </td>
+ </tr>
+ </table>
+ </div>
+ </dd>
+ <dt>
+ Example usage:
+ </dt>
+ <dd>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
# Use an ssh tunnel for requests previously tagged as
# <span class="QUOTE">"User-Agent: fetch libfetch/2.0"</span> and make sure
# resuming downloads continues to work.
TAG:^User-Agent: fetch libfetch/2\.0$
</pre>
- </td>
- </tr>
- </table>
- </dd>
- </dl>
+ </td>
+ </tr>
+ </table>
+ </dd>
+ </dl>
+ </div>
</div>
- </div>
-
- <div class="SECT3">
- <h4 class="SECT3"><a name="HANDLE-AS-EMPTY-DOCUMENT" id=
- "HANDLE-AS-EMPTY-DOCUMENT">8.5.19. handle-as-empty-document</a></h4>
-
- <div class="VARIABLELIST">
- <dl>
- <dt>Typical use:</dt>
-
- <dd>
- <p>Mark URLs that should be replaced by empty documents
- <span class="emphasis"><i class="EMPHASIS">if they get
- blocked</i></span></p>
- </dd>
-
- <dt>Effect:</dt>
-
- <dd>
- <p>This action alone doesn't do anything noticeable. It just
- marks URLs. If the <tt class="LITERAL"><a href=
- "actions-file.html#BLOCK">block</a></tt> action <span class=
- "emphasis"><i class="EMPHASIS">also applies</i></span>, the
- presence or absence of this mark decides whether an HTML
- <span class="QUOTE">"BLOCKED"</span> page, or an empty document
- will be sent to the client as a substitute for the blocked
- content. The <span class="emphasis"><i class=
- "EMPHASIS">empty</i></span> document isn't literally empty, but
- actually contains a single space.</p>
- </dd>
-
- <dt>Type:</dt>
-
- <dd>
- <p>Boolean.</p>
- </dd>
-
- <dt>Parameter:</dt>
-
- <dd>
- <p>N/A</p>
- </dd>
-
- <dt>Notes:</dt>
-
- <dd>
- <p>Some browsers complain about syntax errors if JavaScript
- documents are blocked with <span class=
- "APPLICATION">Privoxy's</span> default HTML page; this option
- can be used to silence them. And of course this action can also
- be used to eliminate the <span class=
- "APPLICATION">Privoxy</span> BLOCKED message in frames.</p>
-
- <p>The content type for the empty document can be specified
- with <tt class="LITERAL"><a href=
- "actions-file.html#CONTENT-TYPE-OVERWRITE">content-type-overwrite{}</a></tt>,
- but usually this isn't necessary.</p>
- </dd>
-
- <dt>Example usage:</dt>
-
- <dd>
- <table border="0" bgcolor="#E0E0E0" width="90%">
- <tr>
- <td>
- <pre class="SCREEN">
+ <div class="SECT3">
+ <h4 class="SECT3">
+ <a name="HANDLE-AS-EMPTY-DOCUMENT">8.5.19.
+ handle-as-empty-document</a>
+ </h4>
+ <div class="VARIABLELIST">
+ <dl>
+ <dt>
+ Typical use:
+ </dt>
+ <dd>
+ <p>
+ Mark URLs that should be replaced by empty documents <span
+ class="emphasis"><i class="EMPHASIS">if they get
+ blocked</i></span>
+ </p>
+ </dd>
+ <dt>
+ Effect:
+ </dt>
+ <dd>
+ <p>
+ This action alone doesn't do anything noticeable. It just
+ marks URLs. If the <tt class="LITERAL"><a href=
+ "actions-file.html#BLOCK">block</a></tt> action <span
+ class="emphasis"><i class="EMPHASIS">also
+ applies</i></span>, the presence or absence of this mark
+ decides whether an HTML <span class=
+ "QUOTE">"BLOCKED"</span> page, or an empty document will be
+ sent to the client as a substitute for the blocked content.
+ The <span class="emphasis"><i class=
+ "EMPHASIS">empty</i></span> document isn't literally empty,
+ but actually contains a single space.
+ </p>
+ </dd>
+ <dt>
+ Type:
+ </dt>
+ <dd>
+ <p>
+ Boolean.
+ </p>
+ </dd>
+ <dt>
+ Parameter:
+ </dt>
+ <dd>
+ <p>
+ N/A
+ </p>
+ </dd>
+ <dt>
+ Notes:
+ </dt>
+ <dd>
+ <p>
+ Some browsers complain about syntax errors if JavaScript
+ documents are blocked with <span class=
+ "APPLICATION">Privoxy's</span> default HTML page; this
+ option can be used to silence them. And of course this
+ action can also be used to eliminate the <span class=
+ "APPLICATION">Privoxy</span> BLOCKED message in frames.
+ </p>
+ <p>
+ The content type for the empty document can be specified
+ with <tt class="LITERAL"><a href=
+ "actions-file.html#CONTENT-TYPE-OVERWRITE">content-type-overwrite{}</a></tt>,
+ but usually this isn't necessary.
+ </p>
+ </dd>
+ <dt>
+ Example usage:
+ </dt>
+ <dd>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
# Block all documents on example.org that end with ".js",
# but send an empty document instead of the usual HTML message.
{+block{Blocked JavaScript} +handle-as-empty-document}
example.org/.*\.js$
</pre>
- </td>
- </tr>
- </table>
- </dd>
- </dl>
- </div>
- </div>
-
- <div class="SECT3">
- <h4 class="SECT3"><a name="HANDLE-AS-IMAGE" id=
- "HANDLE-AS-IMAGE">8.5.20. handle-as-image</a></h4>
-
- <div class="VARIABLELIST">
- <dl>
- <dt>Typical use:</dt>
-
- <dd>
- <p>Mark URLs as belonging to images (so they'll be replaced by
- images <span class="emphasis"><i class="EMPHASIS">if they do
- get blocked</i></span>, rather than HTML pages)</p>
- </dd>
-
- <dt>Effect:</dt>
-
- <dd>
- <p>This action alone doesn't do anything noticeable. It just
- marks URLs as images. If the <tt class="LITERAL"><a href=
- "actions-file.html#BLOCK">block</a></tt> action <span class=
- "emphasis"><i class="EMPHASIS">also applies</i></span>, the
- presence or absence of this mark decides whether an HTML
- <span class="QUOTE">"blocked"</span> page, or a replacement
- image (as determined by the <tt class="LITERAL"><a href=
- "actions-file.html#SET-IMAGE-BLOCKER">set-image-blocker</a></tt>
- action) will be sent to the client as a substitute for the
- blocked content.</p>
- </dd>
-
- <dt>Type:</dt>
-
- <dd>
- <p>Boolean.</p>
- </dd>
-
- <dt>Parameter:</dt>
-
- <dd>
- <p>N/A</p>
- </dd>
-
- <dt>Notes:</dt>
-
- <dd>
- <p>The below generic example section is actually part of
- <tt class="FILENAME">default.action</tt>. It marks all URLs
- with well-known image file name extensions as images and should
- be left intact.</p>
-
- <p>Users will probably only want to use the handle-as-image
- action in conjunction with <tt class="LITERAL"><a href=
- "actions-file.html#BLOCK">block</a></tt>, to block sources of
- banners, whose URLs don't reflect the file type, like in the
- second example section.</p>
-
- <p>Note that you cannot treat HTML pages as images in most
- cases. For instance, (in-line) ad frames require an HTML page
- to be sent, or they won't display properly. Forcing <tt class=
- "LITERAL">handle-as-image</tt> in this situation will not
- replace the ad frame with an image, but lead to error
- messages.</p>
- </dd>
-
- <dt>Example usage (sections):</dt>
-
- <dd>
- <table border="0" bgcolor="#E0E0E0" width="90%">
- <tr>
- <td>
- <pre class="SCREEN">
+ </td>
+ </tr>
+ </table>
+ </dd>
+ </dl>
+ </div>
+ </div>
+ <div class="SECT3">
+ <h4 class="SECT3">
+ <a name="HANDLE-AS-IMAGE">8.5.20. handle-as-image</a>
+ </h4>
+ <div class="VARIABLELIST">
+ <dl>
+ <dt>
+ Typical use:
+ </dt>
+ <dd>
+ <p>
+ Mark URLs as belonging to images (so they'll be replaced by
+ images <span class="emphasis"><i class="EMPHASIS">if they
+ do get blocked</i></span>, rather than HTML pages)
+ </p>
+ </dd>
+ <dt>
+ Effect:
+ </dt>
+ <dd>
+ <p>
+ This action alone doesn't do anything noticeable. It just
+ marks URLs as images. If the <tt class="LITERAL"><a href=
+ "actions-file.html#BLOCK">block</a></tt> action <span
+ class="emphasis"><i class="EMPHASIS">also
+ applies</i></span>, the presence or absence of this mark
+ decides whether an HTML <span class=
+ "QUOTE">"blocked"</span> page, or a replacement image (as
+ determined by the <tt class="LITERAL"><a href=
+ "actions-file.html#SET-IMAGE-BLOCKER">set-image-blocker</a></tt>
+ action) will be sent to the client as a substitute for the
+ blocked content.
+ </p>
+ </dd>
+ <dt>
+ Type:
+ </dt>
+ <dd>
+ <p>
+ Boolean.
+ </p>
+ </dd>
+ <dt>
+ Parameter:
+ </dt>
+ <dd>
+ <p>
+ N/A
+ </p>
+ </dd>
+ <dt>
+ Notes:
+ </dt>
+ <dd>
+ <p>
+ The below generic example section is actually part of <tt
+ class="FILENAME">default.action</tt>. It marks all URLs
+ with well-known image file name extensions as images and
+ should be left intact.
+ </p>
+ <p>
+ Users will probably only want to use the handle-as-image
+ action in conjunction with <tt class="LITERAL"><a href=
+ "actions-file.html#BLOCK">block</a></tt>, to block sources
+ of banners, whose URLs don't reflect the file type, like in
+ the second example section.
+ </p>
+ <p>
+ Note that you cannot treat HTML pages as images in most
+ cases. For instance, (in-line) ad frames require an HTML
+ page to be sent, or they won't display properly. Forcing
+ <tt class="LITERAL">handle-as-image</tt> in this situation
+ will not replace the ad frame with an image, but lead to
+ error messages.
+ </p>
+ </dd>
+ <dt>
+ Example usage (sections):
+ </dt>
+ <dd>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
# Generic image extensions:
#
{+handle-as-image}
{+block{Nasty banners.} +handle-as-image}
nasty-banner-server.example.com/junk.cgi\?output=trash
</pre>
- </td>
- </tr>
- </table>
- </dd>
- </dl>
+ </td>
+ </tr>
+ </table>
+ </dd>
+ </dl>
+ </div>
</div>
- </div>
-
- <div class="SECT3">
- <h4 class="SECT3"><a name="HIDE-ACCEPT-LANGUAGE" id=
- "HIDE-ACCEPT-LANGUAGE">8.5.21. hide-accept-language</a></h4>
-
- <div class="VARIABLELIST">
- <dl>
- <dt>Typical use:</dt>
-
- <dd>
- <p>Pretend to use different language settings.</p>
- </dd>
-
- <dt>Effect:</dt>
-
- <dd>
- <p>Deletes or replaces the <span class=
- "QUOTE">"Accept-Language:"</span> HTTP header in client
- requests.</p>
- </dd>
-
- <dt>Type:</dt>
-
- <dd>
- <p>Parameterized.</p>
- </dd>
-
- <dt>Parameter:</dt>
-
- <dd>
- <p>Keyword: <span class="QUOTE">"block"</span>, or any user
- defined value.</p>
- </dd>
-
- <dt>Notes:</dt>
-
- <dd>
- <p>Faking the browser's language settings can be useful to make
- a foreign User-Agent set with <tt class="LITERAL"><a href=
- "actions-file.html#HIDE-USER-AGENT">hide-user-agent</a></tt>
- more believable.</p>
-
- <p>However some sites with content in different languages check
- the <span class="QUOTE">"Accept-Language:"</span> to decide
- which one to take by default. Sometimes it isn't possible to
- later switch to another language without changing the
- <span class="QUOTE">"Accept-Language:"</span> header first.</p>
-
- <p>Therefore it's a good idea to either only change the
- <span class="QUOTE">"Accept-Language:"</span> header to
- languages you understand, or to languages that aren't wide
- spread.</p>
-
- <p>Before setting the <span class=
- "QUOTE">"Accept-Language:"</span> header to a rare language,
- you should consider that it helps to make your requests unique
- and thus easier to trace. If you don't plan to change this
- header frequently, you should stick to a common language.</p>
- </dd>
-
- <dt>Example usage (section):</dt>
-
- <dd>
- <table border="0" bgcolor="#E0E0E0" width="90%">
- <tr>
- <td>
- <pre class="SCREEN">
+ <div class="SECT3">
+ <h4 class="SECT3">
+ <a name="HIDE-ACCEPT-LANGUAGE">8.5.21. hide-accept-language</a>
+ </h4>
+ <div class="VARIABLELIST">
+ <dl>
+ <dt>
+ Typical use:
+ </dt>
+ <dd>
+ <p>
+ Pretend to use different language settings.
+ </p>
+ </dd>
+ <dt>
+ Effect:
+ </dt>
+ <dd>
+ <p>
+ Deletes or replaces the <span class=
+ "QUOTE">"Accept-Language:"</span> HTTP header in client
+ requests.
+ </p>
+ </dd>
+ <dt>
+ Type:
+ </dt>
+ <dd>
+ <p>
+ Parameterized.
+ </p>
+ </dd>
+ <dt>
+ Parameter:
+ </dt>
+ <dd>
+ <p>
+ Keyword: <span class="QUOTE">"block"</span>, or any user
+ defined value.
+ </p>
+ </dd>
+ <dt>
+ Notes:
+ </dt>
+ <dd>
+ <p>
+ Faking the browser's language settings can be useful to
+ make a foreign User-Agent set with <tt class="LITERAL"><a
+ href=
+ "actions-file.html#HIDE-USER-AGENT">hide-user-agent</a></tt>
+ more believable.
+ </p>
+ <p>
+ However some sites with content in different languages
+ check the <span class="QUOTE">"Accept-Language:"</span> to
+ decide which one to take by default. Sometimes it isn't
+ possible to later switch to another language without
+ changing the <span class="QUOTE">"Accept-Language:"</span>
+ header first.
+ </p>
+ <p>
+ Therefore it's a good idea to either only change the <span
+ class="QUOTE">"Accept-Language:"</span> header to languages
+ you understand, or to languages that aren't wide spread.
+ </p>
+ <p>
+ Before setting the <span class=
+ "QUOTE">"Accept-Language:"</span> header to a rare
+ language, you should consider that it helps to make your
+ requests unique and thus easier to trace. If you don't plan
+ to change this header frequently, you should stick to a
+ common language.
+ </p>
+ </dd>
+ <dt>
+ Example usage (section):
+ </dt>
+ <dd>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
# Pretend to use Canadian language settings.
{+hide-accept-language{en-ca} \
+hide-user-agent{Mozilla/5.0 (X11; U; OpenBSD i386; en-CA; rv:1.8.0.4) Gecko/20060628 Firefox/1.5.0.4} \
}
/
</pre>
- </td>
- </tr>
- </table>
- </dd>
- </dl>
+ </td>
+ </tr>
+ </table>
+ </dd>
+ </dl>
+ </div>
</div>
- </div>
-
- <div class="SECT3">
- <h4 class="SECT3"><a name="HIDE-CONTENT-DISPOSITION" id=
- "HIDE-CONTENT-DISPOSITION">8.5.22. hide-content-disposition</a></h4>
-
- <div class="VARIABLELIST">
- <dl>
- <dt>Typical use:</dt>
-
- <dd>
- <p>Prevent download menus for content you prefer to view inside
- the browser.</p>
- </dd>
-
- <dt>Effect:</dt>
-
- <dd>
- <p>Deletes or replaces the <span class=
- "QUOTE">"Content-Disposition:"</span> HTTP header set by some
- servers.</p>
- </dd>
-
- <dt>Type:</dt>
-
- <dd>
- <p>Parameterized.</p>
- </dd>
-
- <dt>Parameter:</dt>
-
- <dd>
- <p>Keyword: <span class="QUOTE">"block"</span>, or any user
- defined value.</p>
- </dd>
-
- <dt>Notes:</dt>
-
- <dd>
- <p>Some servers set the <span class=
- "QUOTE">"Content-Disposition:"</span> HTTP header for documents
- they assume you want to save locally before viewing them. The
- <span class="QUOTE">"Content-Disposition:"</span> header
- contains the file name the browser is supposed to use by
- default.</p>
-
- <p>In most browsers that understand this header, it makes it
- impossible to <span class="emphasis"><i class="EMPHASIS">just
- view</i></span> the document, without downloading it first,
- even if it's just a simple text file or an image.</p>
-
- <p>Removing the <span class=
- "QUOTE">"Content-Disposition:"</span> header helps to prevent
- this annoyance, but some browsers additionally check the
- <span class="QUOTE">"Content-Type:"</span> header, before they
- decide if they can display a document without saving it first.
- In these cases, you have to change this header as well, before
- the browser stops displaying download menus.</p>
-
- <p>It is also possible to change the server's file name
- suggestion to another one, but in most cases it isn't worth the
- time to set it up.</p>
-
- <p>This action will probably be removed in the future, use
- server-header filters instead.</p>
- </dd>
-
- <dt>Example usage:</dt>
-
- <dd>
- <table border="0" bgcolor="#E0E0E0" width="90%">
- <tr>
- <td>
- <pre class="SCREEN">
+ <div class="SECT3">
+ <h4 class="SECT3">
+ <a name="HIDE-CONTENT-DISPOSITION">8.5.22.
+ hide-content-disposition</a>
+ </h4>
+ <div class="VARIABLELIST">
+ <dl>
+ <dt>
+ Typical use:
+ </dt>
+ <dd>
+ <p>
+ Prevent download menus for content you prefer to view
+ inside the browser.
+ </p>
+ </dd>
+ <dt>
+ Effect:
+ </dt>
+ <dd>
+ <p>
+ Deletes or replaces the <span class=
+ "QUOTE">"Content-Disposition:"</span> HTTP header set by
+ some servers.
+ </p>
+ </dd>
+ <dt>
+ Type:
+ </dt>
+ <dd>
+ <p>
+ Parameterized.
+ </p>
+ </dd>
+ <dt>
+ Parameter:
+ </dt>
+ <dd>
+ <p>
+ Keyword: <span class="QUOTE">"block"</span>, or any user
+ defined value.
+ </p>
+ </dd>
+ <dt>
+ Notes:
+ </dt>
+ <dd>
+ <p>
+ Some servers set the <span class=
+ "QUOTE">"Content-Disposition:"</span> HTTP header for
+ documents they assume you want to save locally before
+ viewing them. The <span class=
+ "QUOTE">"Content-Disposition:"</span> header contains the
+ file name the browser is supposed to use by default.
+ </p>
+ <p>
+ In most browsers that understand this header, it makes it
+ impossible to <span class="emphasis"><i class=
+ "EMPHASIS">just view</i></span> the document, without
+ downloading it first, even if it's just a simple text file
+ or an image.
+ </p>
+ <p>
+ Removing the <span class=
+ "QUOTE">"Content-Disposition:"</span> header helps to
+ prevent this annoyance, but some browsers additionally
+ check the <span class="QUOTE">"Content-Type:"</span>
+ header, before they decide if they can display a document
+ without saving it first. In these cases, you have to change
+ this header as well, before the browser stops displaying
+ download menus.
+ </p>
+ <p>
+ It is also possible to change the server's file name
+ suggestion to another one, but in most cases it isn't worth
+ the time to set it up.
+ </p>
+ <p>
+ This action will probably be removed in the future, use
+ server-header filters instead.
+ </p>
+ </dd>
+ <dt>
+ Example usage:
+ </dt>
+ <dd>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
# Disarm the download link in Sourceforge's patch tracker
{ -filter \
+content-type-overwrite{text/plain}\
+hide-content-disposition{block} }
.sourceforge.net/tracker/download\.php
</pre>
- </td>
- </tr>
- </table>
- </dd>
- </dl>
+ </td>
+ </tr>
+ </table>
+ </dd>
+ </dl>
+ </div>
</div>
- </div>
-
- <div class="SECT3">
- <h4 class="SECT3"><a name="HIDE-IF-MODIFIED-SINCE" id=
- "HIDE-IF-MODIFIED-SINCE">8.5.23. hide-if-modified-since</a></h4>
-
- <div class="VARIABLELIST">
- <dl>
- <dt>Typical use:</dt>
-
- <dd>
- <p>Prevent yet another way to track the user's steps between
- sessions.</p>
- </dd>
-
- <dt>Effect:</dt>
-
- <dd>
- <p>Deletes the <span class="QUOTE">"If-Modified-Since:"</span>
- HTTP client header or modifies its value.</p>
- </dd>
-
- <dt>Type:</dt>
-
- <dd>
- <p>Parameterized.</p>
- </dd>
-
- <dt>Parameter:</dt>
-
- <dd>
- <p>Keyword: <span class="QUOTE">"block"</span>, or a user
- defined value that specifies a range of hours.</p>
- </dd>
-
- <dt>Notes:</dt>
-
- <dd>
- <p>Removing this header is useful for filter testing, where you
- want to force a real reload instead of getting status code
- <span class="QUOTE">"304"</span>, which would cause the browser
- to use a cached copy of the page.</p>
-
- <p>Instead of removing the header, <tt class=
- "LITERAL">hide-if-modified-since</tt> can also add or subtract
- a random amount of time to/from the header's value. You specify
- a range of minutes where the random factor should be chosen
- from and <span class="APPLICATION">Privoxy</span> does the
- rest. A negative value means subtracting, a positive value
- adding.</p>
-
- <p>Randomizing the value of the <span class=
- "QUOTE">"If-Modified-Since:"</span> makes it less likely that
- the server can use the time as a cookie replacement, but you
- will run into caching problems if the random range is too
- high.</p>
-
- <p>It is a good idea to only use a small negative value and let
- <tt class="LITERAL"><a href=
- "actions-file.html#OVERWRITE-LAST-MODIFIED">overwrite-last-modified</a></tt>
- handle the greater changes.</p>
-
- <p>It is also recommended to use this action together with
- <tt class="LITERAL"><a href=
- "actions-file.html#CRUNCH-IF-NONE-MATCH">crunch-if-none-match</a></tt>,
- otherwise it's more or less pointless.</p>
- </dd>
-
- <dt>Example usage (section):</dt>
-
- <dd>
- <table border="0" bgcolor="#E0E0E0" width="90%">
- <tr>
- <td>
- <pre class="SCREEN">
+ <div class="SECT3">
+ <h4 class="SECT3">
+ <a name="HIDE-IF-MODIFIED-SINCE">8.5.23.
+ hide-if-modified-since</a>
+ </h4>
+ <div class="VARIABLELIST">
+ <dl>
+ <dt>
+ Typical use:
+ </dt>
+ <dd>
+ <p>
+ Prevent yet another way to track the user's steps between
+ sessions.
+ </p>
+ </dd>
+ <dt>
+ Effect:
+ </dt>
+ <dd>
+ <p>
+ Deletes the <span class="QUOTE">"If-Modified-Since:"</span>
+ HTTP client header or modifies its value.
+ </p>
+ </dd>
+ <dt>
+ Type:
+ </dt>
+ <dd>
+ <p>
+ Parameterized.
+ </p>
+ </dd>
+ <dt>
+ Parameter:
+ </dt>
+ <dd>
+ <p>
+ Keyword: <span class="QUOTE">"block"</span>, or a user
+ defined value that specifies a range of hours.
+ </p>
+ </dd>
+ <dt>
+ Notes:
+ </dt>
+ <dd>
+ <p>
+ Removing this header is useful for filter testing, where
+ you want to force a real reload instead of getting status
+ code <span class="QUOTE">"304"</span>, which would cause
+ the browser to use a cached copy of the page.
+ </p>
+ <p>
+ Instead of removing the header, <tt class=
+ "LITERAL">hide-if-modified-since</tt> can also add or
+ subtract a random amount of time to/from the header's
+ value. You specify a range of minutes where the random
+ factor should be chosen from and <span class=
+ "APPLICATION">Privoxy</span> does the rest. A negative
+ value means subtracting, a positive value adding.
+ </p>
+ <p>
+ Randomizing the value of the <span class=
+ "QUOTE">"If-Modified-Since:"</span> makes it less likely
+ that the server can use the time as a cookie replacement,
+ but you will run into caching problems if the random range
+ is too high.
+ </p>
+ <p>
+ It is a good idea to only use a small negative value and
+ let <tt class="LITERAL"><a href=
+ "actions-file.html#OVERWRITE-LAST-MODIFIED">overwrite-last-modified</a></tt>
+ handle the greater changes.
+ </p>
+ <p>
+ It is also recommended to use this action together with <tt
+ class="LITERAL"><a href=
+ "actions-file.html#CRUNCH-IF-NONE-MATCH">crunch-if-none-match</a></tt>,
+ otherwise it's more or less pointless.
+ </p>
+ </dd>
+ <dt>
+ Example usage (section):
+ </dt>
+ <dd>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
# Let the browser revalidate but make tracking based on the time less likely.
{+hide-if-modified-since{-60} \
+overwrite-last-modified{randomize} \
+crunch-if-none-match}
/
</pre>
- </td>
- </tr>
- </table>
- </dd>
- </dl>
+ </td>
+ </tr>
+ </table>
+ </dd>
+ </dl>
+ </div>
</div>
- </div>
-
- <div class="SECT3">
- <h4 class="SECT3"><a name="HIDE-FROM-HEADER" id=
- "HIDE-FROM-HEADER">8.5.24. hide-from-header</a></h4>
-
- <div class="VARIABLELIST">
- <dl>
- <dt>Typical use:</dt>
-
- <dd>
- <p>Keep your (old and ill) browser from telling web servers
- your email address</p>
- </dd>
-
- <dt>Effect:</dt>
-
- <dd>
- <p>Deletes any existing <span class="QUOTE">"From:"</span> HTTP
- header, or replaces it with the specified string.</p>
- </dd>
-
- <dt>Type:</dt>
-
- <dd>
- <p>Parameterized.</p>
- </dd>
-
- <dt>Parameter:</dt>
-
- <dd>
- <p>Keyword: <span class="QUOTE">"block"</span>, or any user
- defined value.</p>
- </dd>
-
- <dt>Notes:</dt>
-
- <dd>
- <p>The keyword <span class="QUOTE">"block"</span> will
- completely remove the header (not to be confused with the
- <tt class="LITERAL"><a href=
- "actions-file.html#BLOCK">block</a></tt> action).</p>
-
- <p>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.</p>
-
- <p>This action is rarely needed, as modern web browsers don't
- send <span class="QUOTE">"From:"</span> headers anymore.</p>
- </dd>
-
- <dt>Example usage:</dt>
-
- <dd>
- <table border="0" bgcolor="#E0E0E0" width="90%">
- <tr>
- <td>
- <pre class="SCREEN">
+ <div class="SECT3">
+ <h4 class="SECT3">
+ <a name="HIDE-FROM-HEADER">8.5.24. hide-from-header</a>
+ </h4>
+ <div class="VARIABLELIST">
+ <dl>
+ <dt>
+ Typical use:
+ </dt>
+ <dd>
+ <p>
+ Keep your (old and ill) browser from telling web servers
+ your email address
+ </p>
+ </dd>
+ <dt>
+ Effect:
+ </dt>
+ <dd>
+ <p>
+ Deletes any existing <span class="QUOTE">"From:"</span>
+ HTTP header, or replaces it with the specified string.
+ </p>
+ </dd>
+ <dt>
+ Type:
+ </dt>
+ <dd>
+ <p>
+ Parameterized.
+ </p>
+ </dd>
+ <dt>
+ Parameter:
+ </dt>
+ <dd>
+ <p>
+ Keyword: <span class="QUOTE">"block"</span>, or any user
+ defined value.
+ </p>
+ </dd>
+ <dt>
+ Notes:
+ </dt>
+ <dd>
+ <p>
+ The keyword <span class="QUOTE">"block"</span> will
+ completely remove the header (not to be confused with the
+ <tt class="LITERAL"><a href=
+ "actions-file.html#BLOCK">block</a></tt> action).
+ </p>
+ <p>
+ 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.
+ </p>
+ <p>
+ This action is rarely needed, as modern web browsers don't
+ send <span class="QUOTE">"From:"</span> headers anymore.
+ </p>
+ </dd>
+ <dt>
+ Example usage:
+ </dt>
+ <dd>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
+hide-from-header{block}
</pre>
- </td>
- </tr>
- </table>or
-
- <table border="0" bgcolor="#E0E0E0" width="90%">
- <tr>
- <td>
- <pre class="SCREEN">
+ </td>
+ </tr>
+ </table>
+ or
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
+hide-from-header{spam-me-senseless@sittingduck.example.com}
</pre>
- </td>
- </tr>
- </table>
- </dd>
- </dl>
+ </td>
+ </tr>
+ </table>
+ </dd>
+ </dl>
+ </div>
</div>
- </div>
-
- <div class="SECT3">
- <h4 class="SECT3"><a name="HIDE-REFERRER" id="HIDE-REFERRER">8.5.25.
- hide-referrer</a></h4><a name="HIDE-REFERER" id="HIDE-REFERER"></a>
-
- <div class="VARIABLELIST">
- <dl>
- <dt>Typical use:</dt>
-
- <dd>
- <p>Conceal which link you followed to get to a particular
- site</p>
- </dd>
-
- <dt>Effect:</dt>
-
- <dd>
- <p>Deletes the <span class="QUOTE">"Referer:"</span> (sic) HTTP
- header from the client request, or replaces it with a forged
- one.</p>
- </dd>
-
- <dt>Type:</dt>
-
- <dd>
- <p>Parameterized.</p>
- </dd>
-
- <dt>Parameter:</dt>
-
- <dd>
- <ul>
- <li>
- <p><span class="QUOTE">"conditional-block"</span> to delete
- the header completely if the host has changed.</p>
- </li>
-
- <li>
- <p><span class="QUOTE">"conditional-forge"</span> to forge
- the header if the host has changed.</p>
- </li>
-
- <li>
- <p><span class="QUOTE">"block"</span> to delete the header
- unconditionally.</p>
- </li>
-
- <li>
- <p><span class="QUOTE">"forge"</span> to pretend to be
- coming from the homepage of the server we are talking
- to.</p>
- </li>
-
- <li>
- <p>Any other string to set a user defined referrer.</p>
- </li>
- </ul>
- </dd>
-
- <dt>Notes:</dt>
-
- <dd>
- <p><tt class="LITERAL">conditional-block</tt> is the only
- parameter, that isn't easily detected in the server's log file.
- If it blocks the referrer, the request will look like the
- visitor used a bookmark or typed in the address directly.</p>
-
- <p>Leaving the referrer unmodified for requests on the same
- host allows the server owner to see the visitor's <span class=
- "QUOTE">"click path"</span>, but in most cases she could also
- get that information by comparing other parts of the log file:
- for example the User-Agent if it isn't a very common one, or
- the user's IP address if it doesn't change between different
- requests.</p>
-
- <p>Always blocking the referrer, or using a custom one, can
- lead to failures on servers that check the referrer before they
- answer any requests, in an attempt to prevent their content
- from being embedded or linked to elsewhere.</p>
-
- <p>Both <tt class="LITERAL">conditional-block</tt> and
- <tt class="LITERAL">forge</tt> will work with referrer checks,
- as long as content and valid referring page are on the same
- host. Most of the time that's the case.</p>
-
- <p><tt class="LITERAL">hide-referer</tt> is an alternate
- spelling of <tt class="LITERAL">hide-referrer</tt> and the two
- can be can be freely substituted with each other. (<span class=
- "QUOTE">"referrer"</span> is the correct English spelling,
- however the HTTP specification has a bug - it requires it to be
- spelled as <span class="QUOTE">"referer"</span>.)</p>
- </dd>
-
- <dt>Example usage:</dt>
-
- <dd>
- <table border="0" bgcolor="#E0E0E0" width="90%">
- <tr>
- <td>
- <pre class="SCREEN">
+ <div class="SECT3">
+ <h4 class="SECT3">
+ <a name="HIDE-REFERRER">8.5.25. hide-referrer</a>
+ </h4>
+ <a name="HIDE-REFERER"></a>
+ <div class="VARIABLELIST">
+ <dl>
+ <dt>
+ Typical use:
+ </dt>
+ <dd>
+ <p>
+ Conceal which link you followed to get to a particular site
+ </p>
+ </dd>
+ <dt>
+ Effect:
+ </dt>
+ <dd>
+ <p>
+ Deletes the <span class="QUOTE">"Referer:"</span> (sic)
+ HTTP header from the client request, or replaces it with a
+ forged one.
+ </p>
+ </dd>
+ <dt>
+ Type:
+ </dt>
+ <dd>
+ <p>
+ Parameterized.
+ </p>
+ </dd>
+ <dt>
+ Parameter:
+ </dt>
+ <dd>
+ <ul>
+ <li>
+ <p>
+ <span class="QUOTE">"conditional-block"</span> to
+ delete the header completely if the host has changed.
+ </p>
+ </li>
+ <li>
+ <p>
+ <span class="QUOTE">"conditional-forge"</span> to forge
+ the header if the host has changed.
+ </p>
+ </li>
+ <li>
+ <p>
+ <span class="QUOTE">"block"</span> to delete the header
+ unconditionally.
+ </p>
+ </li>
+ <li>
+ <p>
+ <span class="QUOTE">"forge"</span> to pretend to be
+ coming from the homepage of the server we are talking
+ to.
+ </p>
+ </li>
+ <li>
+ <p>
+ Any other string to set a user defined referrer.
+ </p>
+ </li>
+ </ul>
+ </dd>
+ <dt>
+ Notes:
+ </dt>
+ <dd>
+ <p>
+ <tt class="LITERAL">conditional-block</tt> is the only
+ parameter, that isn't easily detected in the server's log
+ file. If it blocks the referrer, the request will look like
+ the visitor used a bookmark or typed in the address
+ directly.
+ </p>
+ <p>
+ Leaving the referrer unmodified for requests on the same
+ host allows the server owner to see the visitor's <span
+ class="QUOTE">"click path"</span>, but in most cases she
+ could also get that information by comparing other parts of
+ the log file: for example the User-Agent if it isn't a very
+ common one, or the user's IP address if it doesn't change
+ between different requests.
+ </p>
+ <p>
+ Always blocking the referrer, or using a custom one, can
+ lead to failures on servers that check the referrer before
+ they answer any requests, in an attempt to prevent their
+ content from being embedded or linked to elsewhere.
+ </p>
+ <p>
+ Both <tt class="LITERAL">conditional-block</tt> and <tt
+ class="LITERAL">forge</tt> will work with referrer checks,
+ as long as content and valid referring page are on the same
+ host. Most of the time that's the case.
+ </p>
+ <p>
+ <tt class="LITERAL">hide-referer</tt> is an alternate
+ spelling of <tt class="LITERAL">hide-referrer</tt> and the
+ two can be can be freely substituted with each other.
+ (<span class="QUOTE">"referrer"</span> is the correct
+ English spelling, however the HTTP specification has a bug
+ - it requires it to be spelled as <span class=
+ "QUOTE">"referer"</span>.)
+ </p>
+ </dd>
+ <dt>
+ Example usage:
+ </dt>
+ <dd>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
+hide-referrer{forge}
</pre>
- </td>
- </tr>
- </table>or
-
- <table border="0" bgcolor="#E0E0E0" width="90%">
- <tr>
- <td>
- <pre class="SCREEN">
-+hide-referrer{http://www.yahoo.com/}
-</pre>
- </td>
- </tr>
- </table>
- </dd>
- </dl>
- </div>
- </div>
-
- <div class="SECT3">
- <h4 class="SECT3"><a name="HIDE-USER-AGENT" id=
- "HIDE-USER-AGENT">8.5.26. hide-user-agent</a></h4>
-
- <div class="VARIABLELIST">
- <dl>
- <dt>Typical use:</dt>
-
- <dd>
- <p>Try to conceal your type of browser and client operating
- system</p>
- </dd>
-
- <dt>Effect:</dt>
-
- <dd>
- <p>Replaces the value of the <span class=
- "QUOTE">"User-Agent:"</span> HTTP header in client requests
- with the specified value.</p>
- </dd>
-
- <dt>Type:</dt>
-
- <dd>
- <p>Parameterized.</p>
- </dd>
-
- <dt>Parameter:</dt>
-
- <dd>
- <p>Any user-defined string.</p>
- </dd>
-
- <dt>Notes:</dt>
-
- <dd>
- <div class="WARNING">
- <table class="WARNING" border="1" width="90%">
- <tr>
- <td align="center"><b>Warning</b></td>
+ </td>
</tr>
-
+ </table>
+ or
+ <table border="0" bgcolor="#E0E0E0" width="90%">
<tr>
- <td align="left">
- <p>This can lead to problems on web sites that depend
- on looking at this header in order to customize their
- content for different browsers (which, by the way, is
- <span class="emphasis"><i class=
- "EMPHASIS">NOT</i></span> the right thing to do: good
- web sites work browser-independently).</p>
+ <td>
+<pre class="SCREEN">
++hide-referrer{http://www.yahoo.com/}
+</pre>
</td>
</tr>
</table>
- </div>
-
- <p>Using this action in multi-user setups or wherever different
- types of browsers will access the same <span class=
- "APPLICATION">Privoxy</span> is <span class=
- "emphasis"><i class="EMPHASIS">not recommended</i></span>. 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).</p>
-
- <p>More information on known user-agent strings can be found at
- <a href="http://www.user-agents.org/" target=
- "_top">http://www.user-agents.org/</a> and <a href=
- "http://en.wikipedia.org/wiki/User_agent" target=
- "_top">http://en.wikipedia.org/wiki/User_agent</a>.</p>
- </dd>
-
- <dt>Example usage:</dt>
-
- <dd>
- <table border="0" bgcolor="#E0E0E0" width="90%">
- <tr>
- <td>
- <pre class="SCREEN">
+ </dd>
+ </dl>
+ </div>
+ </div>
+ <div class="SECT3">
+ <h4 class="SECT3">
+ <a name="HIDE-USER-AGENT">8.5.26. hide-user-agent</a>
+ </h4>
+ <div class="VARIABLELIST">
+ <dl>
+ <dt>
+ Typical use:
+ </dt>
+ <dd>
+ <p>
+ Try to conceal your type of browser and client operating
+ system
+ </p>
+ </dd>
+ <dt>
+ Effect:
+ </dt>
+ <dd>
+ <p>
+ Replaces the value of the <span class=
+ "QUOTE">"User-Agent:"</span> HTTP header in client requests
+ with the specified value.
+ </p>
+ </dd>
+ <dt>
+ Type:
+ </dt>
+ <dd>
+ <p>
+ Parameterized.
+ </p>
+ </dd>
+ <dt>
+ Parameter:
+ </dt>
+ <dd>
+ <p>
+ Any user-defined string.
+ </p>
+ </dd>
+ <dt>
+ Notes:
+ </dt>
+ <dd>
+ <div class="WARNING">
+ <table class="WARNING" border="1" width="90%">
+ <tr>
+ <td align="CENTER">
+ <b>Warning</b>
+ </td>
+ </tr>
+ <tr>
+ <td align="LEFT">
+ <p>
+ This can lead to problems on web sites that depend
+ on looking at this header in order to customize
+ their content for different browsers (which, by the
+ way, is <span class="emphasis"><i class=
+ "EMPHASIS">NOT</i></span> the right thing to do:
+ good web sites work browser-independently).
+ </p>
+ </td>
+ </tr>
+ </table>
+ </div>
+ <p>
+ Using this action in multi-user setups or wherever
+ different types of browsers will access the same <span
+ class="APPLICATION">Privoxy</span> is <span class=
+ "emphasis"><i class="EMPHASIS">not recommended</i></span>.
+ 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).
+ </p>
+ <p>
+ More information on known user-agent strings can be found
+ at <a href="http://www.user-agents.org/" target=
+ "_top">http://www.user-agents.org/</a> and <a href=
+ "http://en.wikipedia.org/wiki/User_agent" target=
+ "_top">http://en.wikipedia.org/wiki/User_agent</a>.
+ </p>
+ </dd>
+ <dt>
+ Example usage:
+ </dt>
+ <dd>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
+hide-user-agent{Netscape 6.1 (X11; I; Linux 2.4.18 i686)}
</pre>
- </td>
- </tr>
- </table>
- </dd>
- </dl>
+ </td>
+ </tr>
+ </table>
+ </dd>
+ </dl>
+ </div>
</div>
- </div>
-
- <div class="SECT3">
- <h4 class="SECT3"><a name="LIMIT-CONNECT" id="LIMIT-CONNECT">8.5.27.
- limit-connect</a></h4>
-
- <div class="VARIABLELIST">
- <dl>
- <dt>Typical use:</dt>
-
- <dd>
- <p>Prevent abuse of <span class="APPLICATION">Privoxy</span> as
- a TCP proxy relay or disable SSL for untrusted sites</p>
- </dd>
-
- <dt>Effect:</dt>
-
- <dd>
- <p>Specifies to which ports HTTP CONNECT requests are
- allowable.</p>
- </dd>
-
- <dt>Type:</dt>
-
- <dd>
- <p>Parameterized.</p>
- </dd>
-
- <dt>Parameter:</dt>
-
- <dd>
- <p>A comma-separated list of ports or port ranges (the latter
- using dashes, with the minimum defaulting to 0 and the maximum
- to 65K).</p>
- </dd>
-
- <dt>Notes:</dt>
-
- <dd>
- <p>By default, i.e. if no <tt class=
- "LITERAL">limit-connect</tt> action applies, <span class=
- "APPLICATION">Privoxy</span> allows HTTP CONNECT requests to
- all ports. Use <tt class="LITERAL">limit-connect</tt> if
- fine-grained control is desired for some or all
- destinations.</p>
-
- <p>The CONNECT methods exists in HTTP to allow access to secure
- websites (<span class="QUOTE">"https://"</span> 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 means
- CONNECT-enabled proxies can be used as TCP relays very
- easily.</p>
-
- <p><span class="APPLICATION">Privoxy</span> relays HTTPS
- traffic without seeing the decoded content. Websites can
- leverage this limitation to circumvent <span class=
- "APPLICATION">Privoxy</span>'s filters. By specifying an
- invalid port range you can disable HTTPS entirely.</p>
- </dd>
-
- <dt>Example usages:</dt>
-
- <dd>
- <table border="0" bgcolor="#E0E0E0" width="90%">
- <tr>
- <td>
- <pre class="SCREEN">
+ <div class="SECT3">
+ <h4 class="SECT3">
+ <a name="LIMIT-CONNECT">8.5.27. limit-connect</a>
+ </h4>
+ <div class="VARIABLELIST">
+ <dl>
+ <dt>
+ Typical use:
+ </dt>
+ <dd>
+ <p>
+ Prevent abuse of <span class="APPLICATION">Privoxy</span>
+ as a TCP proxy relay or disable SSL for untrusted sites
+ </p>
+ </dd>
+ <dt>
+ Effect:
+ </dt>
+ <dd>
+ <p>
+ Specifies to which ports HTTP CONNECT requests are
+ allowable.
+ </p>
+ </dd>
+ <dt>
+ Type:
+ </dt>
+ <dd>
+ <p>
+ Parameterized.
+ </p>
+ </dd>
+ <dt>
+ Parameter:
+ </dt>
+ <dd>
+ <p>
+ A comma-separated list of ports or port ranges (the latter
+ using dashes, with the minimum defaulting to 0 and the
+ maximum to 65K).
+ </p>
+ </dd>
+ <dt>
+ Notes:
+ </dt>
+ <dd>
+ <p>
+ By default, i.e. if no <tt class=
+ "LITERAL">limit-connect</tt> action applies, <span class=
+ "APPLICATION">Privoxy</span> allows HTTP CONNECT requests
+ to all ports. Use <tt class="LITERAL">limit-connect</tt> if
+ fine-grained control is desired for some or all
+ destinations.
+ </p>
+ <p>
+ The CONNECT methods exists in HTTP to allow access to
+ secure websites (<span class="QUOTE">"https://"</span>
+ 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 means CONNECT-enabled proxies can be
+ used as TCP relays very easily.
+ </p>
+ <p>
+ <span class="APPLICATION">Privoxy</span> relays HTTPS
+ traffic without seeing the decoded content. Websites can
+ leverage this limitation to circumvent <span class=
+ "APPLICATION">Privoxy</span>'s filters. By specifying an
+ invalid port range you can disable HTTPS entirely.
+ </p>
+ </dd>
+ <dt>
+ Example usages:
+ </dt>
+ <dd>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
+limit-connect{443} # Port 443 is OK.
+limit-connect{80,443} # Ports 80 and 443 are OK.
+limit-connect{-3, 7, 20-100, 500-} # Ports less than 3, 7, 20 to 100 and above 500 are OK.
+limit-connect{-} # All ports are OK
+limit-connect{,} # No HTTPS/SSL traffic is allowed
</pre>
- </td>
- </tr>
- </table>
- </dd>
- </dl>
+ </td>
+ </tr>
+ </table>
+ </dd>
+ </dl>
+ </div>
</div>
- </div>
-
- <div class="SECT3">
- <h4 class="SECT3"><a name="LIMIT-COOKIE-LIFETIME" id=
- "LIMIT-COOKIE-LIFETIME">8.5.28. limit-cookie-lifetime</a></h4>
-
- <div class="VARIABLELIST">
- <dl>
- <dt>Typical use:</dt>
-
- <dd>
- <p>Limit the lifetime of HTTP cookies to a couple of minutes or
- hours.</p>
- </dd>
-
- <dt>Effect:</dt>
-
- <dd>
- <p>Overwrites the expires field in Set-Cookie server headers if
- it's above the specified limit.</p>
- </dd>
-
- <dt>Type:</dt>
-
- <dd>
- <p>Parameterized.</p>
- </dd>
-
- <dt>Parameter:</dt>
-
- <dd>
- <p>The lifetime limit in minutes, or 0.</p>
- </dd>
-
- <dt>Notes:</dt>
-
- <dd>
- <p>This action reduces the lifetime of HTTP cookies coming from
- the server to the specified number of minutes, starting from
- the time the cookie passes Privoxy.</p>
-
- <p>Cookies with a lifetime below the limit are not modified.
- The lifetime of session cookies is set to the specified
- limit.</p>
-
- <p>The effect of this action depends on the server.</p>
-
- <p>In case of servers which refresh their cookies with each
- response (or at least frequently), the lifetime limit set by
- this action is updated as well. Thus, a session associated with
- the cookie continues to work with this action enabled, as long
- as a new request is made before the last limit set is
- reached.</p>
-
- <p>However, some servers send their cookies once, with a
- lifetime of several years (the year 2037 is a popular choice),
- and do not refresh them until a certain event in the future,
- for example the user logging out. In this case this action may
- limit the absolute lifetime of the session, even if requests
- are made frequently.</p>
-
- <p>If the parameter is <span class="QUOTE">"0"</span>, this
- action behaves like <tt class="LITERAL"><a href=
- "actions-file.html#SESSION-COOKIES-ONLY">session-cookies-only</a></tt>.</p>
- </dd>
-
- <dt>Example usages:</dt>
-
- <dd>
- <table border="0" bgcolor="#E0E0E0" width="90%">
- <tr>
- <td>
- <pre class="SCREEN">
+ <div class="SECT3">
+ <h4 class="SECT3">
+ <a name="LIMIT-COOKIE-LIFETIME">8.5.28. limit-cookie-lifetime</a>
+ </h4>
+ <div class="VARIABLELIST">
+ <dl>
+ <dt>
+ Typical use:
+ </dt>
+ <dd>
+ <p>
+ Limit the lifetime of HTTP cookies to a couple of minutes
+ or hours.
+ </p>
+ </dd>
+ <dt>
+ Effect:
+ </dt>
+ <dd>
+ <p>
+ Overwrites the expires field in Set-Cookie server headers
+ if it's above the specified limit.
+ </p>
+ </dd>
+ <dt>
+ Type:
+ </dt>
+ <dd>
+ <p>
+ Parameterized.
+ </p>
+ </dd>
+ <dt>
+ Parameter:
+ </dt>
+ <dd>
+ <p>
+ The lifetime limit in minutes, or 0.
+ </p>
+ </dd>
+ <dt>
+ Notes:
+ </dt>
+ <dd>
+ <p>
+ This action reduces the lifetime of HTTP cookies coming
+ from the server to the specified number of minutes,
+ starting from the time the cookie passes Privoxy.
+ </p>
+ <p>
+ Cookies with a lifetime below the limit are not modified.
+ The lifetime of session cookies is set to the specified
+ limit.
+ </p>
+ <p>
+ The effect of this action depends on the server.
+ </p>
+ <p>
+ In case of servers which refresh their cookies with each
+ response (or at least frequently), the lifetime limit set
+ by this action is updated as well. Thus, a session
+ associated with the cookie continues to work with this
+ action enabled, as long as a new request is made before the
+ last limit set is reached.
+ </p>
+ <p>
+ However, some servers send their cookies once, with a
+ lifetime of several years (the year 2037 is a popular
+ choice), and do not refresh them until a certain event in
+ the future, for example the user logging out. In this case
+ this action may limit the absolute lifetime of the session,
+ even if requests are made frequently.
+ </p>
+ <p>
+ If the parameter is <span class="QUOTE">"0"</span>, this
+ action behaves like <tt class="LITERAL"><a href=
+ "actions-file.html#SESSION-COOKIES-ONLY">session-cookies-only</a></tt>.
+ </p>
+ </dd>
+ <dt>
+ Example usages:
+ </dt>
+ <dd>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
+limit-cookie-lifetime{60}
</pre>
- </td>
- </tr>
- </table>
- </dd>
- </dl>
+ </td>
+ </tr>
+ </table>
+ </dd>
+ </dl>
+ </div>
</div>
- </div>
-
- <div class="SECT3">
- <h4 class="SECT3"><a name="PREVENT-COMPRESSION" id=
- "PREVENT-COMPRESSION">8.5.29. prevent-compression</a></h4>
-
- <div class="VARIABLELIST">
- <dl>
- <dt>Typical use:</dt>
-
- <dd>
- <p>Ensure that servers send the content uncompressed, so it can
- be passed through <tt class="LITERAL"><a href=
- "actions-file.html#FILTER">filter</a></tt>s.</p>
- </dd>
-
- <dt>Effect:</dt>
-
- <dd>
- <p>Removes the Accept-Encoding header which can be used to ask
- for compressed transfer.</p>
- </dd>
-
- <dt>Type:</dt>
-
- <dd>
- <p>Boolean.</p>
- </dd>
-
- <dt>Parameter:</dt>
-
- <dd>
- <p>N/A</p>
- </dd>
-
- <dt>Notes:</dt>
-
- <dd>
- <p>More and more websites send their content compressed by
- default, which is generally a good idea and saves bandwidth.
- But the <tt class="LITERAL"><a href=
- "actions-file.html#FILTER">filter</a></tt> and <tt class=
- "LITERAL"><a href=
- "actions-file.html#DEANIMATE-GIFS">deanimate-gifs</a></tt>
- actions need access to the uncompressed data.</p>
-
- <p>When compiled with zlib support (available since
- <span class="APPLICATION">Privoxy</span> 3.0.7), content that
- should be filtered is decompressed on-the-fly and you don't
- have to worry about this action. If you are using an older
- <span class="APPLICATION">Privoxy</span> version, or one that
- hasn't been compiled with zlib support, this action can be used
- to convince the server to send the content uncompressed.</p>
-
- <p>Most text-based instances compress very well, the size is
- seldom decreased by less than 50%, for markup-heavy instances
- like news feeds saving more than 90% of the original size isn't
- unusual.</p>
-
- <p>Not using compression will therefore slow down the transfer,
- and you should only enable this action if you really need it.
- As of <span class="APPLICATION">Privoxy</span> 3.0.7 it's
- disabled in all predefined action settings.</p>
-
- <p>Note that some (rare) ill-configured sites don't handle
- requests for uncompressed documents correctly. Broken PHP
- applications tend to send an empty document body, some IIS
- versions only send the beginning of the content. If you enable
- <tt class="LITERAL">prevent-compression</tt> per default, you
- might want to add exceptions for those sites. See the example
- for how to do that.</p>
- </dd>
-
- <dt>Example usage (sections):</dt>
-
- <dd>
- <table border="0" bgcolor="#E0E0E0" width="90%">
- <tr>
- <td>
- <pre class="SCREEN">
+ <div class="SECT3">
+ <h4 class="SECT3">
+ <a name="PREVENT-COMPRESSION">8.5.29. prevent-compression</a>
+ </h4>
+ <div class="VARIABLELIST">
+ <dl>
+ <dt>
+ Typical use:
+ </dt>
+ <dd>
+ <p>
+ Ensure that servers send the content uncompressed, so it
+ can be passed through <tt class="LITERAL"><a href=
+ "actions-file.html#FILTER">filter</a></tt>s.
+ </p>
+ </dd>
+ <dt>
+ Effect:
+ </dt>
+ <dd>
+ <p>
+ Removes the Accept-Encoding header which can be used to ask
+ for compressed transfer.
+ </p>
+ </dd>
+ <dt>
+ Type:
+ </dt>
+ <dd>
+ <p>
+ Boolean.
+ </p>
+ </dd>
+ <dt>
+ Parameter:
+ </dt>
+ <dd>
+ <p>
+ N/A
+ </p>
+ </dd>
+ <dt>
+ Notes:
+ </dt>
+ <dd>
+ <p>
+ More and more websites send their content compressed by
+ default, which is generally a good idea and saves
+ bandwidth. But the <tt class="LITERAL"><a href=
+ "actions-file.html#FILTER">filter</a></tt> and <tt class=
+ "LITERAL"><a href=
+ "actions-file.html#DEANIMATE-GIFS">deanimate-gifs</a></tt>
+ actions need access to the uncompressed data.
+ </p>
+ <p>
+ When compiled with zlib support (available since <span
+ class="APPLICATION">Privoxy</span> 3.0.7), content that
+ should be filtered is decompressed on-the-fly and you don't
+ have to worry about this action. If you are using an older
+ <span class="APPLICATION">Privoxy</span> version, or one
+ that hasn't been compiled with zlib support, this action
+ can be used to convince the server to send the content
+ uncompressed.
+ </p>
+ <p>
+ Most text-based instances compress very well, the size is
+ seldom decreased by less than 50%, for markup-heavy
+ instances like news feeds saving more than 90% of the
+ original size isn't unusual.
+ </p>
+ <p>
+ Not using compression will therefore slow down the
+ transfer, and you should only enable this action if you
+ really need it. As of <span class=
+ "APPLICATION">Privoxy</span> 3.0.7 it's disabled in all
+ predefined action settings.
+ </p>
+ <p>
+ Note that some (rare) ill-configured sites don't handle
+ requests for uncompressed documents correctly. Broken PHP
+ applications tend to send an empty document body, some IIS
+ versions only send the beginning of the content. If you
+ enable <tt class="LITERAL">prevent-compression</tt> per
+ default, you might want to add exceptions for those sites.
+ See the example for how to do that.
+ </p>
+ </dd>
+ <dt>
+ Example usage (sections):
+ </dt>
+ <dd>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
# Selectively turn off compression, and enable a filter
#
{ +filter{tiny-textforms} +prevent-compression }
{ -prevent-compression }
.compusa.com/
</pre>
- </td>
- </tr>
- </table>
- </dd>
- </dl>
+ </td>
+ </tr>
+ </table>
+ </dd>
+ </dl>
+ </div>
</div>
- </div>
-
- <div class="SECT3">
- <h4 class="SECT3"><a name="OVERWRITE-LAST-MODIFIED" id=
- "OVERWRITE-LAST-MODIFIED">8.5.30. overwrite-last-modified</a></h4>
-
- <div class="VARIABLELIST">
- <dl>
- <dt>Typical use:</dt>
-
- <dd>
- <p>Prevent yet another way to track the user's steps between
- sessions.</p>
- </dd>
-
- <dt>Effect:</dt>
-
- <dd>
- <p>Deletes the <span class="QUOTE">"Last-Modified:"</span> HTTP
- server header or modifies its value.</p>
- </dd>
-
- <dt>Type:</dt>
-
- <dd>
- <p>Parameterized.</p>
- </dd>
-
- <dt>Parameter:</dt>
-
- <dd>
- <p>One of the keywords: <span class="QUOTE">"block"</span>,
- <span class="QUOTE">"reset-to-request-time"</span> and
- <span class="QUOTE">"randomize"</span></p>
- </dd>
-
- <dt>Notes:</dt>
-
- <dd>
- <p>Removing the <span class="QUOTE">"Last-Modified:"</span>
- header is useful for filter testing, where you want to force a
- real reload instead of getting status code <span class=
- "QUOTE">"304"</span>, which would cause the browser to reuse
- the old version of the page.</p>
-
- <p>The <span class="QUOTE">"randomize"</span> option overwrites
- the value of the <span class="QUOTE">"Last-Modified:"</span>
- header with a randomly chosen time between the original value
- and the current time. In theory the server could send each
- document with a different <span class=
- "QUOTE">"Last-Modified:"</span> header to track visits without
- using cookies. <span class="QUOTE">"Randomize"</span> makes it
- impossible and the browser can still revalidate cached
- documents.</p>
-
- <p><span class="QUOTE">"reset-to-request-time"</span>
- overwrites the value of the <span class=
- "QUOTE">"Last-Modified:"</span> header with the current time.
- You could use this option together with <tt class=
- "LITERAL"><a href=
- "actions-file.html#HIDE-IF-MODIFIED-SINCE">hide-if-modified-since</a></tt>
- to further customize your random range.</p>
-
- <p>The preferred parameter here is <span class=
- "QUOTE">"randomize"</span>. It is safe to use, as long as the
- time settings are more or less correct. If the server sets the
- <span class="QUOTE">"Last-Modified:"</span> header to the time
- of the request, the random range becomes zero and the value
- stays the same. Therefore you should later randomize it a
- second time with <tt class="LITERAL"><a href=
- "actions-file.html#HIDE-IF-MODIFIED-SINCE">hided-if-modified-since</a></tt>,
- just to be sure.</p>
-
- <p>It is also recommended to use this action together with
- <tt class="LITERAL"><a href=
- "actions-file.html#CRUNCH-IF-NONE-MATCH">crunch-if-none-match</a></tt>.</p>
- </dd>
-
- <dt>Example usage:</dt>
-
- <dd>
- <table border="0" bgcolor="#E0E0E0" width="90%">
- <tr>
- <td>
- <pre class="SCREEN">
+ <div class="SECT3">
+ <h4 class="SECT3">
+ <a name="OVERWRITE-LAST-MODIFIED">8.5.30.
+ overwrite-last-modified</a>
+ </h4>
+ <div class="VARIABLELIST">
+ <dl>
+ <dt>
+ Typical use:
+ </dt>
+ <dd>
+ <p>
+ Prevent yet another way to track the user's steps between
+ sessions.
+ </p>
+ </dd>
+ <dt>
+ Effect:
+ </dt>
+ <dd>
+ <p>
+ Deletes the <span class="QUOTE">"Last-Modified:"</span>
+ HTTP server header or modifies its value.
+ </p>
+ </dd>
+ <dt>
+ Type:
+ </dt>
+ <dd>
+ <p>
+ Parameterized.
+ </p>
+ </dd>
+ <dt>
+ Parameter:
+ </dt>
+ <dd>
+ <p>
+ One of the keywords: <span class="QUOTE">"block"</span>,
+ <span class="QUOTE">"reset-to-request-time"</span> and
+ <span class="QUOTE">"randomize"</span>
+ </p>
+ </dd>
+ <dt>
+ Notes:
+ </dt>
+ <dd>
+ <p>
+ Removing the <span class="QUOTE">"Last-Modified:"</span>
+ header is useful for filter testing, where you want to
+ force a real reload instead of getting status code <span
+ class="QUOTE">"304"</span>, which would cause the browser
+ to reuse the old version of the page.
+ </p>
+ <p>
+ The <span class="QUOTE">"randomize"</span> option
+ overwrites the value of the <span class=
+ "QUOTE">"Last-Modified:"</span> header with a randomly
+ chosen time between the original value and the current
+ time. In theory the server could send each document with a
+ different <span class="QUOTE">"Last-Modified:"</span>
+ header to track visits without using cookies. <span class=
+ "QUOTE">"Randomize"</span> makes it impossible and the
+ browser can still revalidate cached documents.
+ </p>
+ <p>
+ <span class="QUOTE">"reset-to-request-time"</span>
+ overwrites the value of the <span class=
+ "QUOTE">"Last-Modified:"</span> header with the current
+ time. You could use this option together with <tt class=
+ "LITERAL"><a href=
+ "actions-file.html#HIDE-IF-MODIFIED-SINCE">hide-if-modified-since</a></tt>
+ to further customize your random range.
+ </p>
+ <p>
+ The preferred parameter here is <span class=
+ "QUOTE">"randomize"</span>. It is safe to use, as long as
+ the time settings are more or less correct. If the server
+ sets the <span class="QUOTE">"Last-Modified:"</span> header
+ to the time of the request, the random range becomes zero
+ and the value stays the same. Therefore you should later
+ randomize it a second time with <tt class="LITERAL"><a
+ href=
+ "actions-file.html#HIDE-IF-MODIFIED-SINCE">hided-if-modified-since</a></tt>,
+ just to be sure.
+ </p>
+ <p>
+ It is also recommended to use this action together with <tt
+ class="LITERAL"><a href=
+ "actions-file.html#CRUNCH-IF-NONE-MATCH">crunch-if-none-match</a></tt>.
+ </p>
+ </dd>
+ <dt>
+ Example usage:
+ </dt>
+ <dd>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
# Let the browser revalidate without being tracked across sessions
{ +hide-if-modified-since{-60} \
+overwrite-last-modified{randomize} \
+crunch-if-none-match}
/
</pre>
- </td>
- </tr>
- </table>
- </dd>
- </dl>
+ </td>
+ </tr>
+ </table>
+ </dd>
+ </dl>
+ </div>
</div>
- </div>
-
- <div class="SECT3">
- <h4 class="SECT3"><a name="REDIRECT" id="REDIRECT">8.5.31.
- redirect</a></h4>
-
- <div class="VARIABLELIST">
- <dl>
- <dt>Typical use:</dt>
-
- <dd>
- <p>Redirect requests to other sites.</p>
- </dd>
-
- <dt>Effect:</dt>
-
- <dd>
- <p>Convinces the browser that the requested document has been
- moved to another location and the browser should get it from
- there.</p>
- </dd>
-
- <dt>Type:</dt>
-
- <dd>
- <p>Parameterized</p>
- </dd>
-
- <dt>Parameter:</dt>
-
- <dd>
- <p>An absolute URL or a single pcrs command.</p>
- </dd>
-
- <dt>Notes:</dt>
-
- <dd>
- <p>Requests to which this action applies are answered with a
- HTTP redirect to URLs of your choosing. The new URL is either
- provided as parameter, or derived by applying a single pcrs
- command to the original URL.</p>
-
- <p>The syntax for pcrs commands is documented in the <a href=
- "filter-file.html">filter file</a> section.</p>
-
- <p>Requests can't be blocked and redirected at the same time,
- applying this action together with <tt class="LITERAL"><a href=
- "actions-file.html#BLOCK">block</a></tt> is a configuration
- error. Currently the request is blocked and an error message
- logged, the behavior may change in the future and result in
- Privoxy rejecting the action file.</p>
-
- <p>This action can be combined with <tt class=
- "LITERAL"><a href="actions-file.html#FAST-REDIRECTS">fast-redirects{check-decoded-url}</a></tt>
- to redirect to a decoded version of a rewritten URL.</p>
-
- <p>Use this action carefully, make sure not to create
- redirection loops and be aware that using your own redirects
- might make it possible to fingerprint your requests.</p>
-
- <p>In case of problems with your redirects, or simply to watch
- them working, enable <a href="config.html#DEBUG">debug
- 128</a>.</p>
- </dd>
-
- <dt>Example usages:</dt>
-
- <dd>
- <table border="0" bgcolor="#E0E0E0" width="90%">
- <tr>
- <td>
- <pre class="SCREEN">
+ <div class="SECT3">
+ <h4 class="SECT3">
+ <a name="REDIRECT">8.5.31. redirect</a>
+ </h4>
+ <div class="VARIABLELIST">
+ <dl>
+ <dt>
+ Typical use:
+ </dt>
+ <dd>
+ <p>
+ Redirect requests to other sites.
+ </p>
+ </dd>
+ <dt>
+ Effect:
+ </dt>
+ <dd>
+ <p>
+ Convinces the browser that the requested document has been
+ moved to another location and the browser should get it
+ from there.
+ </p>
+ </dd>
+ <dt>
+ Type:
+ </dt>
+ <dd>
+ <p>
+ Parameterized
+ </p>
+ </dd>
+ <dt>
+ Parameter:
+ </dt>
+ <dd>
+ <p>
+ An absolute URL or a single pcrs command.
+ </p>
+ </dd>
+ <dt>
+ Notes:
+ </dt>
+ <dd>
+ <p>
+ Requests to which this action applies are answered with a
+ HTTP redirect to URLs of your choosing. The new URL is
+ either provided as parameter, or derived by applying a
+ single pcrs command to the original URL.
+ </p>
+ <p>
+ The syntax for pcrs commands is documented in the <a href=
+ "filter-file.html">filter file</a> section.
+ </p>
+ <p>
+ Requests can't be blocked and redirected at the same time,
+ applying this action together with <tt class="LITERAL"><a
+ href="actions-file.html#BLOCK">block</a></tt> is a
+ configuration error. Currently the request is blocked and
+ an error message logged, the behavior may change in the
+ future and result in Privoxy rejecting the action file.
+ </p>
+ <p>
+ This action can be combined with <tt class="LITERAL"><a
+ href=
+ "actions-file.html#FAST-REDIRECTS">fast-redirects{check-decoded-url}</a></tt>
+ to redirect to a decoded version of a rewritten URL.
+ </p>
+ <p>
+ Use this action carefully, make sure not to create
+ redirection loops and be aware that using your own
+ redirects might make it possible to fingerprint your
+ requests.
+ </p>
+ <p>
+ In case of problems with your redirects, or simply to watch
+ them working, enable <a href="config.html#DEBUG">debug
+ 128</a>.
+ </p>
+ </dd>
+ <dt>
+ Example usages:
+ </dt>
+ <dd>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
# Replace example.com's style sheet with another one
{ +redirect{http://localhost/css-replacements/example.com.css} }
example.com/stylesheet\.css
# Redirect remote requests for this manual
# to the local version delivered by Privoxy
-{+redirect{s@^http://www@http://config@}}
-www.privoxy.org/user-manual/
-</pre>
- </td>
- </tr>
- </table>
- </dd>
- </dl>
- </div>
- </div>
-
- <div class="SECT3">
- <h4 class="SECT3"><a name="SERVER-HEADER-FILTER" id=
- "SERVER-HEADER-FILTER">8.5.32. server-header-filter</a></h4>
-
- <div class="VARIABLELIST">
- <dl>
- <dt>Typical use:</dt>
-
- <dd>
- <p>Rewrite or remove single server headers.</p>
- </dd>
-
- <dt>Effect:</dt>
-
- <dd>
- <p>All server headers to which this action applies are filtered
- on-the-fly through the specified regular expression based
- substitutions.</p>
- </dd>
-
- <dt>Type:</dt>
-
- <dd>
- <p>Multi-value.</p>
- </dd>
-
- <dt>Parameter:</dt>
-
- <dd>
- <p>The name of a server-header filter, as defined in one of the
- <a href="filter-file.html">filter files</a>.</p>
- </dd>
-
- <dt>Notes:</dt>
-
- <dd>
- <p>Server-header filters are applied to each header on its own,
- not to all at once. This makes it easier to diagnose problems,
- but on the downside you can't write filters that only change
- header x if header y's value is z. You can do that by using
- tags though.</p>
-
- <p>Server-header filters are executed after the other header
- actions have finished and use their output as input.</p>
-
- <p>Please refer to the <a href="filter-file.html">filter file
- chapter</a> to learn which server-header filters are available
- by default, and how to create your own.</p>
- </dd>
-
- <dt>Example usage (section):</dt>
-
- <dd>
- <table border="0" bgcolor="#E0E0E0" width="90%">
- <tr>
- <td>
- <pre class="SCREEN">
+{+redirect{s@^http://www@http://config@}}
+www.privoxy.org/user-manual/
+</pre>
+ </td>
+ </tr>
+ </table>
+ </dd>
+ </dl>
+ </div>
+ </div>
+ <div class="SECT3">
+ <h4 class="SECT3">
+ <a name="SERVER-HEADER-FILTER">8.5.32. server-header-filter</a>
+ </h4>
+ <div class="VARIABLELIST">
+ <dl>
+ <dt>
+ Typical use:
+ </dt>
+ <dd>
+ <p>
+ Rewrite or remove single server headers.
+ </p>
+ </dd>
+ <dt>
+ Effect:
+ </dt>
+ <dd>
+ <p>
+ All server headers to which this action applies are
+ filtered on-the-fly through the specified regular
+ expression based substitutions.
+ </p>
+ </dd>
+ <dt>
+ Type:
+ </dt>
+ <dd>
+ <p>
+ Multi-value.
+ </p>
+ </dd>
+ <dt>
+ Parameter:
+ </dt>
+ <dd>
+ <p>
+ The name of a server-header filter, as defined in one of
+ the <a href="filter-file.html">filter files</a>.
+ </p>
+ </dd>
+ <dt>
+ Notes:
+ </dt>
+ <dd>
+ <p>
+ Server-header filters are applied to each header on its
+ own, not to all at once. This makes it easier to diagnose
+ problems, but on the downside you can't write filters that
+ only change header x if header y's value is z. You can do
+ that by using tags though.
+ </p>
+ <p>
+ Server-header filters are executed after the other header
+ actions have finished and use their output as input.
+ </p>
+ <p>
+ Please refer to the <a href="filter-file.html">filter file
+ chapter</a> to learn which server-header filters are
+ available by default, and how to create your own.
+ </p>
+ </dd>
+ <dt>
+ Example usage (section):
+ </dt>
+ <dd>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
{+server-header-filter{html-to-xml}}
example.org/xml-instance-that-is-delivered-as-html
example.org/instance-that-is-delivered-as-xml-but-is-not
</pre>
- </td>
- </tr>
- </table>
- </dd>
- </dl>
+ </td>
+ </tr>
+ </table>
+ </dd>
+ </dl>
+ </div>
</div>
- </div>
-
- <div class="SECT3">
- <h4 class="SECT3"><a name="SERVER-HEADER-TAGGER" id=
- "SERVER-HEADER-TAGGER">8.5.33. server-header-tagger</a></h4>
-
- <div class="VARIABLELIST">
- <dl>
- <dt>Typical use:</dt>
-
- <dd>
- <p>Enable or disable filters based on the Content-Type
- header.</p>
- </dd>
-
- <dt>Effect:</dt>
-
- <dd>
- <p>Server headers to which this action applies are filtered
- on-the-fly through the specified regular expression based
- substitutions, the result is used as tag.</p>
- </dd>
-
- <dt>Type:</dt>
-
- <dd>
- <p>Multi-value.</p>
- </dd>
-
- <dt>Parameter:</dt>
-
- <dd>
- <p>The name of a server-header tagger, as defined in one of the
- <a href="filter-file.html">filter files</a>.</p>
- </dd>
-
- <dt>Notes:</dt>
-
- <dd>
- <p>Server-header taggers are applied to each header on its own,
- and as the header isn't modified, each tagger <span class=
- "QUOTE">"sees"</span> the original.</p>
-
- <p>Server-header taggers are executed before all other header
- actions that modify server headers. Their tags can be used to
- control all of the other server-header actions, the content
- filters and the crunch actions (<a href=
- "actions-file.html#REDIRECT">redirect</a> and <a href=
- "actions-file.html#BLOCK">block</a>).</p>
-
- <p>Obviously crunching based on tags created by server-header
- taggers doesn't prevent the request from showing up in the
- server's log file.</p>
- </dd>
-
- <dt>Example usage (section):</dt>
-
- <dd>
- <table border="0" bgcolor="#E0E0E0" width="90%">
- <tr>
- <td>
- <pre class="SCREEN">
+ <div class="SECT3">
+ <h4 class="SECT3">
+ <a name="SERVER-HEADER-TAGGER">8.5.33. server-header-tagger</a>
+ </h4>
+ <div class="VARIABLELIST">
+ <dl>
+ <dt>
+ Typical use:
+ </dt>
+ <dd>
+ <p>
+ Enable or disable filters based on the Content-Type header.
+ </p>
+ </dd>
+ <dt>
+ Effect:
+ </dt>
+ <dd>
+ <p>
+ Server headers to which this action applies are filtered
+ on-the-fly through the specified regular expression based
+ substitutions, the result is used as tag.
+ </p>
+ </dd>
+ <dt>
+ Type:
+ </dt>
+ <dd>
+ <p>
+ Multi-value.
+ </p>
+ </dd>
+ <dt>
+ Parameter:
+ </dt>
+ <dd>
+ <p>
+ The name of a server-header tagger, as defined in one of
+ the <a href="filter-file.html">filter files</a>.
+ </p>
+ </dd>
+ <dt>
+ Notes:
+ </dt>
+ <dd>
+ <p>
+ Server-header taggers are applied to each header on its
+ own, and as the header isn't modified, each tagger <span
+ class="QUOTE">"sees"</span> the original.
+ </p>
+ <p>
+ Server-header taggers are executed before all other header
+ actions that modify server headers. Their tags can be used
+ to control all of the other server-header actions, the
+ content filters and the crunch actions (<a href=
+ "actions-file.html#REDIRECT">redirect</a> and <a href=
+ "actions-file.html#BLOCK">block</a>).
+ </p>
+ <p>
+ Obviously crunching based on tags created by server-header
+ taggers doesn't prevent the request from showing up in the
+ server's log file.
+ </p>
+ </dd>
+ <dt>
+ Example usage (section):
+ </dt>
+ <dd>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
# Tag every request with the content type declared by the server
{+server-header-tagger{content-type}}
/
TAG:^image/
</pre>
- </td>
- </tr>
- </table>
- </dd>
- </dl>
+ </td>
+ </tr>
+ </table>
+ </dd>
+ </dl>
+ </div>
</div>
- </div>
-
- <div class="SECT3">
- <h4 class="SECT3"><a name="SESSION-COOKIES-ONLY" id=
- "SESSION-COOKIES-ONLY">8.5.34. session-cookies-only</a></h4>
-
- <div class="VARIABLELIST">
- <dl>
- <dt>Typical use:</dt>
-
- <dd>
- <p>Allow only temporary <span class="QUOTE">"session"</span>
- cookies (for the current browser session <span class=
- "emphasis"><i class="EMPHASIS">only</i></span>).</p>
- </dd>
-
- <dt>Effect:</dt>
-
- <dd>
- <p>Deletes the <span class="QUOTE">"expires"</span> field from
- <span class="QUOTE">"Set-Cookie:"</span> server headers. Most
- browsers will not store such cookies permanently and forget
- them in between sessions.</p>
- </dd>
-
- <dt>Type:</dt>
-
- <dd>
- <p>Boolean.</p>
- </dd>
-
- <dt>Parameter:</dt>
-
- <dd>
- <p>N/A</p>
- </dd>
-
- <dt>Notes:</dt>
-
- <dd>
- <p>This is less strict than <tt class="LITERAL"><a href=
- "actions-file.html#CRUNCH-INCOMING-COOKIES">crunch-incoming-cookies</a></tt>
- / <tt class="LITERAL"><a href=
- "actions-file.html#CRUNCH-OUTGOING-COOKIES">crunch-outgoing-cookies</a></tt>
- and allows you to browse websites that insist or rely on
- setting cookies, without compromising your privacy too
- badly.</p>
-
- <p>Most browsers will not permanently store cookies that have
- been processed by <tt class="LITERAL">session-cookies-only</tt>
- 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.</p>
-
- <p>It makes <span class="emphasis"><i class="EMPHASIS">no sense
- at all</i></span> to use <tt class=
- "LITERAL">session-cookies-only</tt> together with <tt class=
- "LITERAL"><a href=
- "actions-file.html#CRUNCH-INCOMING-COOKIES">crunch-incoming-cookies</a></tt>
- or <tt class="LITERAL"><a href=
- "actions-file.html#CRUNCH-OUTGOING-COOKIES">crunch-outgoing-cookies</a></tt>.
- If you do, cookies will be plainly killed.</p>
-
- <p>Note that it is up to the browser how it handles such
- cookies without an <span class="QUOTE">"expires"</span> field.
- If you use an exotic browser, you might want to try it out to
- be sure.</p>
-
- <p>This setting also has no effect on cookies that may have
- been stored previously by the browser before starting
- <span class="APPLICATION">Privoxy</span>. These would have to
- be removed manually.</p>
-
- <p><span class="APPLICATION">Privoxy</span> also uses the
- <a href=
- "actions-file.html#FILTER-CONTENT-COOKIES">content-cookies
- filter</a> to block some types of cookies. Content cookies are
- not effected by <tt class=
- "LITERAL">session-cookies-only</tt>.</p>
- </dd>
-
- <dt>Example usage:</dt>
-
- <dd>
- <table border="0" bgcolor="#E0E0E0" width="90%">
- <tr>
- <td>
- <pre class="SCREEN">
+ <div class="SECT3">
+ <h4 class="SECT3">
+ <a name="SESSION-COOKIES-ONLY">8.5.34. session-cookies-only</a>
+ </h4>
+ <div class="VARIABLELIST">
+ <dl>
+ <dt>
+ Typical use:
+ </dt>
+ <dd>
+ <p>
+ Allow only temporary <span class="QUOTE">"session"</span>
+ cookies (for the current browser session <span class=
+ "emphasis"><i class="EMPHASIS">only</i></span>).
+ </p>
+ </dd>
+ <dt>
+ Effect:
+ </dt>
+ <dd>
+ <p>
+ Deletes the <span class="QUOTE">"expires"</span> field from
+ <span class="QUOTE">"Set-Cookie:"</span> server headers.
+ Most browsers will not store such cookies permanently and
+ forget them in between sessions.
+ </p>
+ </dd>
+ <dt>
+ Type:
+ </dt>
+ <dd>
+ <p>
+ Boolean.
+ </p>
+ </dd>
+ <dt>
+ Parameter:
+ </dt>
+ <dd>
+ <p>
+ N/A
+ </p>
+ </dd>
+ <dt>
+ Notes:
+ </dt>
+ <dd>
+ <p>
+ This is less strict than <tt class="LITERAL"><a href=
+ "actions-file.html#CRUNCH-INCOMING-COOKIES">crunch-incoming-cookies</a></tt>
+ / <tt class="LITERAL"><a href=
+ "actions-file.html#CRUNCH-OUTGOING-COOKIES">crunch-outgoing-cookies</a></tt>
+ and allows you to browse websites that insist or rely on
+ setting cookies, without compromising your privacy too
+ badly.
+ </p>
+ <p>
+ Most browsers will not permanently store cookies that have
+ been processed by <tt class=
+ "LITERAL">session-cookies-only</tt> 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.
+ </p>
+ <p>
+ It makes <span class="emphasis"><i class="EMPHASIS">no
+ sense at all</i></span> to use <tt class=
+ "LITERAL">session-cookies-only</tt> together with <tt
+ class="LITERAL"><a href=
+ "actions-file.html#CRUNCH-INCOMING-COOKIES">crunch-incoming-cookies</a></tt>
+ or <tt class="LITERAL"><a href=
+ "actions-file.html#CRUNCH-OUTGOING-COOKIES">crunch-outgoing-cookies</a></tt>.
+ If you do, cookies will be plainly killed.
+ </p>
+ <p>
+ Note that it is up to the browser how it handles such
+ cookies without an <span class="QUOTE">"expires"</span>
+ field. If you use an exotic browser, you might want to try
+ it out to be sure.
+ </p>
+ <p>
+ This setting also has no effect on cookies that may have
+ been stored previously by the browser before starting <span
+ class="APPLICATION">Privoxy</span>. These would have to be
+ removed manually.
+ </p>
+ <p>
+ <span class="APPLICATION">Privoxy</span> also uses the <a
+ href=
+ "actions-file.html#FILTER-CONTENT-COOKIES">content-cookies
+ filter</a> to block some types of cookies. Content cookies
+ are not effected by <tt class=
+ "LITERAL">session-cookies-only</tt>.
+ </p>
+ </dd>
+ <dt>
+ Example usage:
+ </dt>
+ <dd>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
+session-cookies-only
</pre>
- </td>
- </tr>
- </table>
- </dd>
- </dl>
+ </td>
+ </tr>
+ </table>
+ </dd>
+ </dl>
+ </div>
</div>
- </div>
-
- <div class="SECT3">
- <h4 class="SECT3"><a name="SET-IMAGE-BLOCKER" id=
- "SET-IMAGE-BLOCKER">8.5.35. set-image-blocker</a></h4>
-
- <div class="VARIABLELIST">
- <dl>
- <dt>Typical use:</dt>
-
- <dd>
- <p>Choose the replacement for blocked images</p>
- </dd>
-
- <dt>Effect:</dt>
-
- <dd>
- <p>This action alone doesn't do anything noticeable. If
- <span class="emphasis"><i class="EMPHASIS">both</i></span>
- <tt class="LITERAL"><a href=
- "actions-file.html#BLOCK">block</a></tt> <span class=
- "emphasis"><i class="EMPHASIS">and</i></span> <tt class=
- "LITERAL"><a href=
- "actions-file.html#HANDLE-AS-IMAGE">handle-as-image</a></tt>
- <span class="emphasis"><i class="EMPHASIS">also</i></span>
- apply, i.e. if the request is to be blocked as an image,
- <span class="emphasis"><i class="EMPHASIS">then</i></span> the
- parameter of this action decides what will be sent as a
- replacement.</p>
- </dd>
-
- <dt>Type:</dt>
-
- <dd>
- <p>Parameterized.</p>
- </dd>
-
- <dt>Parameter:</dt>
-
- <dd>
- <ul>
- <li>
- <p><span class="QUOTE">"pattern"</span> to send a built-in
- checkerboard pattern image. The image is visually decent,
- scales very well, and makes it obvious where banners were
- busted.</p>
- </li>
-
- <li>
- <p><span class="QUOTE">"blank"</span> to send a built-in
- transparent image. This makes banners disappear completely,
- but makes it hard to detect where <span class=
- "APPLICATION">Privoxy</span> has blocked images on a given
- page and complicates troubleshooting if <span class=
- "APPLICATION">Privoxy</span> has blocked innocent images,
- like navigation icons.</p>
- </li>
-
- <li>
- <p><span class="QUOTE">"<tt class=
- "REPLACEABLE"><i>target-url</i></tt>"</span> to send a
- redirect to <tt class="REPLACEABLE"><i>target-url</i></tt>.
- You can redirect to any image anywhere, even in your local
- filesystem via <span class="QUOTE">"file:///"</span> URL.
- (But note that not all browsers support redirecting to a
- local file system).</p>
-
- <p>A good application of redirects is to use special
- <span class="APPLICATION">Privoxy</span>-built-in URLs,
- which send the built-in images, as <tt class=
- "REPLACEABLE"><i>target-url</i></tt>. This has the same
- visual effect as specifying <span class=
+ <div class="SECT3">
+ <h4 class="SECT3">
+ <a name="SET-IMAGE-BLOCKER">8.5.35. set-image-blocker</a>
+ </h4>
+ <div class="VARIABLELIST">
+ <dl>
+ <dt>
+ Typical use:
+ </dt>
+ <dd>
+ <p>
+ Choose the replacement for blocked images
+ </p>
+ </dd>
+ <dt>
+ Effect:
+ </dt>
+ <dd>
+ <p>
+ This action alone doesn't do anything noticeable. If <span
+ class="emphasis"><i class="EMPHASIS">both</i></span> <tt
+ class="LITERAL"><a href=
+ "actions-file.html#BLOCK">block</a></tt> <span class=
+ "emphasis"><i class="EMPHASIS">and</i></span> <tt class=
+ "LITERAL"><a href=
+ "actions-file.html#HANDLE-AS-IMAGE">handle-as-image</a></tt>
+ <span class="emphasis"><i class="EMPHASIS">also</i></span>
+ apply, i.e. if the request is to be blocked as an image,
+ <span class="emphasis"><i class="EMPHASIS">then</i></span>
+ the parameter of this action decides what will be sent as a
+ replacement.
+ </p>
+ </dd>
+ <dt>
+ Type:
+ </dt>
+ <dd>
+ <p>
+ Parameterized.
+ </p>
+ </dd>
+ <dt>
+ Parameter:
+ </dt>
+ <dd>
+ <ul>
+ <li>
+ <p>
+ <span class="QUOTE">"pattern"</span> to send a built-in
+ checkerboard pattern image. The image is visually
+ decent, scales very well, and makes it obvious where
+ banners were busted.
+ </p>
+ </li>
+ <li>
+ <p>
+ <span class="QUOTE">"blank"</span> to send a built-in
+ transparent image. This makes banners disappear
+ completely, but makes it hard to detect where <span
+ class="APPLICATION">Privoxy</span> has blocked images
+ on a given page and complicates troubleshooting if
+ <span class="APPLICATION">Privoxy</span> has blocked
+ innocent images, like navigation icons.
+ </p>
+ </li>
+ <li>
+ <p>
+ <span class="QUOTE">"<tt class=
+ "REPLACEABLE"><i>target-url</i></tt>"</span> to send a
+ redirect to <tt class=
+ "REPLACEABLE"><i>target-url</i></tt>. You can redirect
+ to any image anywhere, even in your local filesystem
+ via <span class="QUOTE">"file:///"</span> URL. (But
+ note that not all browsers support redirecting to a
+ local file system).
+ </p>
+ <p>
+ A good application of redirects is to use special <span
+ class="APPLICATION">Privoxy</span>-built-in URLs, which
+ send the built-in images, as <tt class=
+ "REPLACEABLE"><i>target-url</i></tt>. This has the same
+ visual effect as specifying <span class=
+ "QUOTE">"blank"</span> or <span class=
+ "QUOTE">"pattern"</span> in the first place, but
+ enables your browser to cache the replacement image,
+ instead of requesting it over and over again.
+ </p>
+ </li>
+ </ul>
+ </dd>
+ <dt>
+ Notes:
+ </dt>
+ <dd>
+ <p>
+ The URLs for the built-in images are <span class=
+ "QUOTE">"http://config.privoxy.org/send-banner?type=<tt
+ class="REPLACEABLE"><i>type</i></tt>"</span>, where <tt
+ class="REPLACEABLE"><i>type</i></tt> is either <span class=
"QUOTE">"blank"</span> or <span class=
- "QUOTE">"pattern"</span> in the first place, but enables
- your browser to cache the replacement image, instead of
- requesting it over and over again.</p>
- </li>
- </ul>
- </dd>
-
- <dt>Notes:</dt>
-
- <dd>
- <p>The URLs for the built-in images are <span class=
- "QUOTE">"http://config.privoxy.org/send-banner?type=<tt class=
- "REPLACEABLE"><i>type</i></tt>"</span>, where <tt class=
- "REPLACEABLE"><i>type</i></tt> is either <span class=
- "QUOTE">"blank"</span> or <span class=
- "QUOTE">"pattern"</span>.</p>
-
- <p>There is a third (advanced) type, called <span class=
- "QUOTE">"auto"</span>. It is <span class="emphasis"><i class=
- "EMPHASIS">NOT</i></span> to be used in <tt class=
- "LITERAL">set-image-blocker</tt>, but meant for use from
- <a href="filter-file.html">filters</a>. Auto will select the
- type of image that would have applied to the referring page,
- had it been an image.</p>
- </dd>
-
- <dt>Example usage:</dt>
-
- <dd>
- <p>Built-in pattern:</p>
-
- <table border="0" bgcolor="#E0E0E0" width="90%">
- <tr>
- <td>
- <pre class="SCREEN">
+ "QUOTE">"pattern"</span>.
+ </p>
+ <p>
+ There is a third (advanced) type, called <span class=
+ "QUOTE">"auto"</span>. It is <span class="emphasis"><i
+ class="EMPHASIS">NOT</i></span> to be used in <tt class=
+ "LITERAL">set-image-blocker</tt>, but meant for use from <a
+ href="filter-file.html">filters</a>. Auto will select the
+ type of image that would have applied to the referring
+ page, had it been an image.
+ </p>
+ </dd>
+ <dt>
+ Example usage:
+ </dt>
+ <dd>
+ <p>
+ Built-in pattern:
+ </p>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
+set-image-blocker{pattern}
</pre>
- </td>
- </tr>
- </table>
-
- <p>Redirect to the BSD daemon:</p>
+ </td>
+ </tr>
+ </table>
- <table border="0" bgcolor="#E0E0E0" width="90%">
- <tr>
- <td>
- <pre class="SCREEN">
+ <p>
+ Redirect to the BSD daemon:
+ </p>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
+set-image-blocker{http://www.freebsd.org/gifs/dae_up3.gif}
</pre>
- </td>
- </tr>
- </table>
-
- <p>Redirect to the built-in pattern for better caching:</p>
+ </td>
+ </tr>
+ </table>
- <table border="0" bgcolor="#E0E0E0" width="90%">
- <tr>
- <td>
- <pre class="SCREEN">
+ <p>
+ Redirect to the built-in pattern for better caching:
+ </p>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="90%">
+ <tr>
+ <td>
+<pre class="SCREEN">
+set-image-blocker{http://config.privoxy.org/send-banner?type=pattern}
</pre>
- </td>
- </tr>
- </table>
- </dd>
- </dl>
+ </td>
+ </tr>
+ </table>
+ </dd>
+ </dl>
+ </div>
+ </div>
+ <div class="SECT3">
+ <h3 class="SECT3">
+ <a name="SUMMARY">8.5.36. Summary</a>
+ </h3>
+ <p>
+ Note that many of these actions have the potential to cause a
+ page to misbehave, possibly even not to display at all. There are
+ many ways a site designer may choose to design his site, and what
+ HTTP header content, and other criteria, he may depend on. There
+ is no way to have hard and fast rules for all sites. See the <a
+ href="appendix.html#ACTIONSANAT">Appendix</a> for a brief example
+ on troubleshooting actions.
+ </p>
</div>
</div>
-
- <div class="SECT3">
- <h3 class="SECT3"><a name="SUMMARY" id="SUMMARY">8.5.36.
- Summary</a></h3>
-
- <p>Note that many of these actions have the potential to cause a page
- to misbehave, possibly even not to display at all. There are many
- ways a site designer may choose to design his site, and what HTTP
- header content, and other criteria, he may depend on. There is no way
- to have hard and fast rules for all sites. See the <a href=
- "appendix.html#ACTIONSANAT">Appendix</a> for a brief example on
- troubleshooting actions.</p>
- </div>
- </div>
-
- <div class="SECT2">
- <h2 class="SECT2"><a name="ALIASES" id="ALIASES">8.6. Aliases</a></h2>
-
- <p>Custom <span class="QUOTE">"actions"</span>, known to <span class=
- "APPLICATION">Privoxy</span> as <span class="QUOTE">"aliases"</span>,
- 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, <span class="QUOTE">"="</span>,
- <span class="QUOTE">"{"</span> and <span class="QUOTE">"}"</span>, but
- we <span class="emphasis"><i class="EMPHASIS">strongly
- recommend</i></span> that you only use <span class="QUOTE">"a"</span>
- to <span class="QUOTE">"z"</span>, <span class="QUOTE">"0"</span> to
- <span class="QUOTE">"9"</span>, <span class="QUOTE">"+"</span>, and
- <span class="QUOTE">"-"</span>. Alias names are not case sensitive, and
- are not required to start with a <span class="QUOTE">"+"</span> or
- <span class="QUOTE">"-"</span> sign, since they are merely textually
- expanded.</p>
-
- <p>Aliases can be used throughout the actions file, but they
- <span class="emphasis"><i class="EMPHASIS">must be defined in a special
- section at the top of the file!</i></span> 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.</p>
-
- <p>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 <span class="QUOTE">"shop"</span>, you can
- later change your policy on shops in <span class="emphasis"><i class=
- "EMPHASIS">one</i></span> place, and your changes will take effect
- everywhere in the actions file where the <span class=
- "QUOTE">"shop"</span> alias is used. Calling aliases by their purpose
- also makes your actions files more readable.</p>
-
- <p>Currently, there is one big drawback to using aliases, though:
- <span class="APPLICATION">Privoxy</span>'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.</p>
-
- <p>Now let's define some aliases...</p>
-
- <table border="0" bgcolor="#E0E0E0" width="100%">
- <tr>
- <td>
- <pre class="SCREEN">
+ <div class="SECT2">
+ <h2 class="SECT2">
+ <a name="ALIASES">8.6. Aliases</a>
+ </h2>
+ <p>
+ Custom <span class="QUOTE">"actions"</span>, known to <span class=
+ "APPLICATION">Privoxy</span> as <span class=
+ "QUOTE">"aliases"</span>, 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, <span class="QUOTE">"="</span>, <span class=
+ "QUOTE">"{"</span> and <span class="QUOTE">"}"</span>, but we <span
+ class="emphasis"><i class="EMPHASIS">strongly recommend</i></span>
+ that you only use <span class="QUOTE">"a"</span> to <span class=
+ "QUOTE">"z"</span>, <span class="QUOTE">"0"</span> to <span class=
+ "QUOTE">"9"</span>, <span class="QUOTE">"+"</span>, and <span
+ class="QUOTE">"-"</span>. Alias names are not case sensitive, and
+ are not required to start with a <span class="QUOTE">"+"</span> or
+ <span class="QUOTE">"-"</span> sign, since they are merely
+ textually expanded.
+ </p>
+ <p>
+ Aliases can be used throughout the actions file, but they <span
+ class="emphasis"><i class="EMPHASIS">must be defined in a special
+ section at the top of the file!</i></span> 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.
+ </p>
+ <p>
+ 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 <span class=
+ "QUOTE">"shop"</span>, you can later change your policy on shops in
+ <span class="emphasis"><i class="EMPHASIS">one</i></span> place,
+ and your changes will take effect everywhere in the actions file
+ where the <span class="QUOTE">"shop"</span> alias is used. Calling
+ aliases by their purpose also makes your actions files more
+ readable.
+ </p>
+ <p>
+ Currently, there is one big drawback to using aliases, though:
+ <span class="APPLICATION">Privoxy</span>'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.
+ </p>
+ <p>
+ Now let's define some aliases...
+ </p>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="100%">
+ <tr>
+ <td>
+<pre class="SCREEN">
# Useful custom aliases we can use later.
#
# Note the (required!) section header line and that this section
# (Note that some already use other aliases!)
#
+crunch-all-cookies = +<a href=
-"actions-file.html#CRUNCH-INCOMING-COOKIES">crunch-incoming-cookies</a> +<a href="actions-file.html#CRUNCH-OUTGOING-COOKIES">crunch-outgoing-cookies</a>
+"actions-file.html#CRUNCH-INCOMING-COOKIES">crunch-incoming-cookies</a> +<a
+href="actions-file.html#CRUNCH-OUTGOING-COOKIES">crunch-outgoing-cookies</a>
-crunch-all-cookies = -<a href=
-"actions-file.html#CRUNCH-INCOMING-COOKIES">crunch-incoming-cookies</a> -<a href="actions-file.html#CRUNCH-OUTGOING-COOKIES">crunch-outgoing-cookies</a>
+"actions-file.html#CRUNCH-INCOMING-COOKIES">crunch-incoming-cookies</a> -<a
+href="actions-file.html#CRUNCH-OUTGOING-COOKIES">crunch-outgoing-cookies</a>
+block-as-image = +block{Blocked image.} +handle-as-image
allow-all-cookies = -crunch-all-cookies -<a href=
"actions-file.html#SESSION-COOKIES-ONLY">session-cookies-only</a> -<a href=
c0 = +crunch-all-cookies
c1 = -crunch-all-cookies
</pre>
- </td>
- </tr>
- </table>
-
- <p>...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 <span class="QUOTE">"/"</span>
- pattern):</p>
+ </td>
+ </tr>
+ </table>
- <table border="0" bgcolor="#E0E0E0" width="100%">
- <tr>
- <td>
- <pre class="SCREEN">
+ <p>
+ ...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 <span class=
+ "QUOTE">"/"</span> pattern):
+ </p>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="100%">
+ <tr>
+ <td>
+<pre class="SCREEN">
# These sites are either very complex or very keen on
# user data and require minimal interference to work:
#
.dabs.com
.overclockers.co.uk
</pre>
- </td>
- </tr>
- </table>
-
- <p>Aliases like <span class="QUOTE">"shop"</span> and <span class=
- "QUOTE">"fragile"</span> are typically used for <span class=
- "QUOTE">"problem"</span> sites that require more than one action to be
- disabled in order to function properly.</p>
- </div>
-
- <div class="SECT2">
- <h2 class="SECT2"><a name="ACT-EXAMPLES" id="ACT-EXAMPLES">8.7. Actions
- Files Tutorial</a></h2>
-
- <p>The above chapters have shown <a href="actions-file.html">which
- actions files there are and how they are organized</a>, how actions are
- <a href="actions-file.html#ACTIONS">specified</a> and <a href=
- "actions-file.html#ACTIONS-APPLY">applied to URLs</a>, how <a href=
- "actions-file.html#AF-PATTERNS">patterns</a> work, and how to define
- and use <a href="actions-file.html#ALIASES">aliases</a>. Now, let's
- look at an example <tt class="FILENAME">match-all.action</tt>,
- <tt class="FILENAME">default.action</tt> and <tt class=
- "FILENAME">user.action</tt> file and see how all these pieces come
- together:</p>
-
- <div class="SECT3">
- <h3 class="SECT3"><a name="MATCH-ALL" id="MATCH-ALL">8.7.1.
- match-all.action</a></h3>
-
- <p>Remember <span class="emphasis"><i class="EMPHASIS">all actions
- are disabled when matching starts</i></span>, so we have to
- explicitly enable the ones we want.</p>
-
- <p>While the <tt class="FILENAME">match-all.action</tt> file only
- contains a single section, it is probably the most important one. It
- has only one pattern, <span class="QUOTE">"<tt class=
- "LITERAL">/</tt>"</span>, but this pattern <a href=
- "actions-file.html#AF-PATTERNS">matches all URLs</a>. Therefore, the
- set of actions used in this <span class="QUOTE">"default"</span>
- section <span class="emphasis"><i class="EMPHASIS">will be applied to
- all requests as a start</i></span>. It can be partly or wholly
- overridden by other actions files like <tt class=
- "FILENAME">default.action</tt> and <tt class=
- "FILENAME">user.action</tt>, but it will still be largely responsible
- for your overall browsing experience.</p>
-
- <p>Again, at the start of matching, all actions are disabled, so
- there is no need to disable any actions here. (Remember: a
- <span class="QUOTE">"+"</span> preceding the action name enables the
- action, a <span class="QUOTE">"-"</span> disables!). Also note how
- this long line has been made more readable by splitting it into
- multiple lines with line continuation.</p>
+ </td>
+ </tr>
+ </table>
- <table border="0" bgcolor="#E0E0E0" width="100%">
- <tr>
- <td>
- <pre class="SCREEN">
+ <p>
+ Aliases like <span class="QUOTE">"shop"</span> and <span class=
+ "QUOTE">"fragile"</span> are typically used for <span class=
+ "QUOTE">"problem"</span> sites that require more than one action to
+ be disabled in order to function properly.
+ </p>
+ </div>
+ <div class="SECT2">
+ <h2 class="SECT2">
+ <a name="ACT-EXAMPLES">8.7. Actions Files Tutorial</a>
+ </h2>
+ <p>
+ The above chapters have shown <a href="actions-file.html">which
+ actions files there are and how they are organized</a>, how actions
+ are <a href="actions-file.html#ACTIONS">specified</a> and <a href=
+ "actions-file.html#ACTIONS-APPLY">applied to URLs</a>, how <a href=
+ "actions-file.html#AF-PATTERNS">patterns</a> work, and how to
+ define and use <a href="actions-file.html#ALIASES">aliases</a>.
+ Now, let's look at an example <tt class=
+ "FILENAME">match-all.action</tt>, <tt class=
+ "FILENAME">default.action</tt> and <tt class=
+ "FILENAME">user.action</tt> file and see how all these pieces come
+ together:
+ </p>
+ <div class="SECT3">
+ <h3 class="SECT3">
+ <a name="MATCH-ALL">8.7.1. match-all.action</a>
+ </h3>
+ <p>
+ Remember <span class="emphasis"><i class="EMPHASIS">all actions
+ are disabled when matching starts</i></span>, so we have to
+ explicitly enable the ones we want.
+ </p>
+ <p>
+ While the <tt class="FILENAME">match-all.action</tt> file only
+ contains a single section, it is probably the most important one.
+ It has only one pattern, <span class="QUOTE">"<tt class=
+ "LITERAL">/</tt>"</span>, but this pattern <a href=
+ "actions-file.html#AF-PATTERNS">matches all URLs</a>. Therefore,
+ the set of actions used in this <span class=
+ "QUOTE">"default"</span> section <span class="emphasis"><i class=
+ "EMPHASIS">will be applied to all requests as a start</i></span>.
+ It can be partly or wholly overridden by other actions files like
+ <tt class="FILENAME">default.action</tt> and <tt class=
+ "FILENAME">user.action</tt>, but it will still be largely
+ responsible for your overall browsing experience.
+ </p>
+ <p>
+ Again, at the start of matching, all actions are disabled, so
+ there is no need to disable any actions here. (Remember: a <span
+ class="QUOTE">"+"</span> preceding the action name enables the
+ action, a <span class="QUOTE">"-"</span> disables!). Also note
+ how this long line has been made more readable by splitting it
+ into multiple lines with line continuation.
+ </p>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="100%">
+ <tr>
+ <td>
+<pre class="SCREEN">
{ \
+<a href=
"actions-file.html#CHANGE-X-FORWARDED-FOR">change-x-forwarded-for{block}</a> \
"actions-file.html#SET-IMAGE-BLOCKER">set-image-blocker{pattern}</a> \
}
/ # Match all URLs
-
</pre>
- </td>
- </tr>
- </table>
-
- <p>The default behavior is now set.</p>
- </div>
-
- <div class="SECT3">
- <h3 class="SECT3"><a name="DEFAULT-ACTION" id="DEFAULT-ACTION">8.7.2.
- default.action</a></h3>
-
- <p>If you aren't a developer, there's no need for you to edit the
- <tt class="FILENAME">default.action</tt> file. It is maintained by
- the <span class="APPLICATION">Privoxy</span> developers and if you
- disagree with some of the sections, you should overrule them in your
- <tt class="FILENAME">user.action</tt>.</p>
-
- <p>Understanding the <tt class="FILENAME">default.action</tt> file
- can help you with your <tt class="FILENAME">user.action</tt>,
- though.</p>
-
- <p>The first section in this file is a special section for internal
- use that prevents older <span class="APPLICATION">Privoxy</span>
- versions from reading the file:</p>
+ </td>
+ </tr>
+ </table>
- <table border="0" bgcolor="#E0E0E0" width="100%">
- <tr>
- <td>
- <pre class="SCREEN">
+ <p>
+ The default behavior is now set.
+ </p>
+ </div>
+ <div class="SECT3">
+ <h3 class="SECT3">
+ <a name="DEFAULT-ACTION">8.7.2. default.action</a>
+ </h3>
+ <p>
+ If you aren't a developer, there's no need for you to edit the
+ <tt class="FILENAME">default.action</tt> file. It is maintained
+ by the <span class="APPLICATION">Privoxy</span> developers and if
+ you disagree with some of the sections, you should overrule them
+ in your <tt class="FILENAME">user.action</tt>.
+ </p>
+ <p>
+ Understanding the <tt class="FILENAME">default.action</tt> file
+ can help you with your <tt class="FILENAME">user.action</tt>,
+ though.
+ </p>
+ <p>
+ The first section in this file is a special section for internal
+ use that prevents older <span class="APPLICATION">Privoxy</span>
+ versions from reading the file:
+ </p>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="100%">
+ <tr>
+ <td>
+<pre class="SCREEN">
##########################################################################
# Settings -- Don't change! For internal Privoxy use ONLY.
##########################################################################
{{settings}}
for-privoxy-version=3.0.11
</pre>
- </td>
- </tr>
- </table>
-
- <p>After that comes the (optional) alias section. We'll use the
- example section from the above <a href=
- "actions-file.html#ALIASES">chapter on aliases</a>, that also
- explains why and how aliases are used:</p>
+ </td>
+ </tr>
+ </table>
- <table border="0" bgcolor="#E0E0E0" width="100%">
- <tr>
- <td>
- <pre class="SCREEN">
+ <p>
+ After that comes the (optional) alias section. We'll use the
+ example section from the above <a href=
+ "actions-file.html#ALIASES">chapter on aliases</a>, that also
+ explains why and how aliases are used:
+ </p>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="100%">
+ <tr>
+ <td>
+<pre class="SCREEN">
##########################################################################
# Aliases
##########################################################################
# (Note that some already use other aliases!)
#
+crunch-all-cookies = +<a href=
-"actions-file.html#CRUNCH-INCOMING-COOKIES">crunch-incoming-cookies</a> +<a href="actions-file.html#CRUNCH-OUTGOING-COOKIES">crunch-outgoing-cookies</a>
+"actions-file.html#CRUNCH-INCOMING-COOKIES">crunch-incoming-cookies</a> +<a
+href="actions-file.html#CRUNCH-OUTGOING-COOKIES">crunch-outgoing-cookies</a>
-crunch-all-cookies = -<a href=
-"actions-file.html#CRUNCH-INCOMING-COOKIES">crunch-incoming-cookies</a> -<a href="actions-file.html#CRUNCH-OUTGOING-COOKIES">crunch-outgoing-cookies</a>
+"actions-file.html#CRUNCH-INCOMING-COOKIES">crunch-incoming-cookies</a> -<a
+href="actions-file.html#CRUNCH-OUTGOING-COOKIES">crunch-outgoing-cookies</a>
+block-as-image = +block{Blocked image.} +handle-as-image
mercy-for-cookies = -crunch-all-cookies -<a href=
"actions-file.html#SESSION-COOKIES-ONLY">session-cookies-only</a> -<a href=
shop = -crunch-all-cookies -<a href=
"actions-file.html#FILTER-ALL-POPUPS">filter{all-popups}</a>
</pre>
- </td>
- </tr>
- </table>
-
- <p>The first of our specialized sections is concerned with
- <span class="QUOTE">"fragile"</span> 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 <tt class="LITERAL">fragile</tt> alias instead of stating
- the list of actions explicitly:</p>
+ </td>
+ </tr>
+ </table>
- <table border="0" bgcolor="#E0E0E0" width="100%">
- <tr>
- <td>
- <pre class="SCREEN">
+ <p>
+ The first of our specialized sections is concerned with <span
+ class="QUOTE">"fragile"</span> 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 <tt class="LITERAL">fragile</tt> alias
+ instead of stating the list of actions explicitly:
+ </p>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="100%">
+ <tr>
+ <td>
+<pre class="SCREEN">
##########################################################################
# Exceptions for sites that'll break under the default action set:
##########################################################################
.windowsupdate.microsoft.com
mail.google.com
</pre>
- </td>
- </tr>
- </table>
-
- <p>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:</p>
+ </td>
+ </tr>
+ </table>
- <table border="0" bgcolor="#E0E0E0" width="100%">
- <tr>
- <td>
- <pre class="SCREEN">
+ <p>
+ 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:
+ </p>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="100%">
+ <tr>
+ <td>
+<pre class="SCREEN">
# Shopping sites:
#
{ shop }
.jungle.com
.scan.co.uk
</pre>
- </td>
- </tr>
- </table>
-
- <p>The <tt class="LITERAL"><a href=
- "actions-file.html#FAST-REDIRECTS">fast-redirects</a></tt> action,
- which may have been enabled in <tt class=
- "FILENAME">match-all.action</tt>, breaks some sites. So disable it
- for popular sites where we know it misbehaves:</p>
+ </td>
+ </tr>
+ </table>
- <table border="0" bgcolor="#E0E0E0" width="100%">
- <tr>
- <td>
- <pre class="SCREEN">
+ <p>
+ The <tt class="LITERAL"><a href=
+ "actions-file.html#FAST-REDIRECTS">fast-redirects</a></tt>
+ action, which may have been enabled in <tt class=
+ "FILENAME">match-all.action</tt>, breaks some sites. So disable
+ it for popular sites where we know it misbehaves:
+ </p>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="100%">
+ <tr>
+ <td>
+<pre class="SCREEN">
{ -<a href="actions-file.html#FAST-REDIRECTS">fast-redirects</a> }
login.yahoo.com
edit.*.yahoo.com
.altavista.com/trans.*urltext=http
.nytimes.com
</pre>
- </td>
- </tr>
- </table>
-
- <p>It is important that <span class="APPLICATION">Privoxy</span>
- knows which URLs belong to images, so that <span class=
- "emphasis"><i class="EMPHASIS">if</i></span> 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 information about you. We can mark any URL as an image
- with the <tt class="LITERAL"><a href=
- "actions-file.html#HANDLE-AS-IMAGE">handle-as-image</a></tt> action,
- and marking all URLs that end in a known image file extension is a
- good start:</p>
+ </td>
+ </tr>
+ </table>
- <table border="0" bgcolor="#E0E0E0" width="100%">
- <tr>
- <td>
- <pre class="SCREEN">
+ <p>
+ It is important that <span class="APPLICATION">Privoxy</span>
+ knows which URLs belong to images, so that <span class=
+ "emphasis"><i class="EMPHASIS">if</i></span> 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 information about
+ you. We can mark any URL as an image with the <tt class=
+ "LITERAL"><a href=
+ "actions-file.html#HANDLE-AS-IMAGE">handle-as-image</a></tt>
+ action, and marking all URLs that end in a known image file
+ extension is a good start:
+ </p>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="100%">
+ <tr>
+ <td>
+<pre class="SCREEN">
##########################################################################
# Images:
##########################################################################
{ +<a href="actions-file.html#HANDLE-AS-IMAGE">handle-as-image</a> }
/.*\.(gif|jpe?g|png|bmp|ico)$
</pre>
- </td>
- </tr>
- </table>
-
- <p>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 <span class=
- "emphasis"><i class="EMPHASIS">and</i></span> mark them as images in
- one go, with the help of our <tt class="LITERAL">+block-as-image</tt>
- alias defined above. (We could of course just as well use <tt class=
- "LITERAL">+<a href="actions-file.html#BLOCK">block</a> +<a href=
- "actions-file.html#HANDLE-AS-IMAGE">handle-as-image</a></tt> here.)
- Remember that the type of the replacement image is chosen by the
- <tt class="LITERAL"><a href=
- "actions-file.html#SET-IMAGE-BLOCKER">set-image-blocker</a></tt>
- action. Since all URLs have matched the default section with its
- <tt class="LITERAL">+<a href=
- "actions-file.html#SET-IMAGE-BLOCKER">set-image-blocker</a>{pattern}</tt>
- action before, it still applies and needn't be repeated:</p>
+ </td>
+ </tr>
+ </table>
- <table border="0" bgcolor="#E0E0E0" width="100%">
- <tr>
- <td>
- <pre class="SCREEN">
+ <p>
+ 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 <span class=
+ "emphasis"><i class="EMPHASIS">and</i></span> mark them as images
+ in one go, with the help of our <tt class=
+ "LITERAL">+block-as-image</tt> alias defined above. (We could of
+ course just as well use <tt class="LITERAL">+<a href=
+ "actions-file.html#BLOCK">block</a> +<a href=
+ "actions-file.html#HANDLE-AS-IMAGE">handle-as-image</a></tt>
+ here.) Remember that the type of the replacement image is chosen
+ by the <tt class="LITERAL"><a href=
+ "actions-file.html#SET-IMAGE-BLOCKER">set-image-blocker</a></tt>
+ action. Since all URLs have matched the default section with its
+ <tt class="LITERAL">+<a href=
+ "actions-file.html#SET-IMAGE-BLOCKER">set-image-blocker</a>{pattern}</tt>
+ action before, it still applies and needn't be repeated:
+ </p>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="100%">
+ <tr>
+ <td>
+<pre class="SCREEN">
# Known ad generators:
#
{ +block-as-image }
bs*.gsanet.com
.qkimg.net
</pre>
- </td>
- </tr>
- </table>
-
- <p>One of the most important jobs of <span class=
- "APPLICATION">Privoxy</span> is to block banners. Many of these can
- be <span class="QUOTE">"blocked"</span> by the <tt class=
- "LITERAL"><a href=
- "actions-file.html#FILTER">filter</a>{banners-by-size}</tt> 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 <tt class="LITERAL"><a href=
- "actions-file.html#BLOCK">block</a></tt> action to them.</p>
-
- <p>First comes many 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:</p>
+ </td>
+ </tr>
+ </table>
- <table border="0" bgcolor="#E0E0E0" width="100%">
- <tr>
- <td>
- <pre class="SCREEN">
+ <p>
+ One of the most important jobs of <span class=
+ "APPLICATION">Privoxy</span> is to block banners. Many of these
+ can be <span class="QUOTE">"blocked"</span> by the <tt class=
+ "LITERAL"><a href=
+ "actions-file.html#FILTER">filter</a>{banners-by-size}</tt>
+ 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 <tt class="LITERAL"><a href=
+ "actions-file.html#BLOCK">block</a></tt> action to them.
+ </p>
+ <p>
+ First comes many 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:
+ </p>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="100%">
+ <tr>
+ <td>
+<pre class="SCREEN">
##########################################################################
# Block these fine banners:
##########################################################################
#
.hitbox.com
</pre>
- </td>
- </tr>
- </table>
-
- <p>It's quite remarkable how many advertisers actually call their
- banner servers ads.<tt class="REPLACEABLE"><i>company</i></tt>.com,
- or call the directory in which the banners are stored simply
- <span class="QUOTE">"banners"</span>. So the above generic patterns
- are surprisingly effective.</p>
-
- <p>But being very generic, they necessarily also catch URLs that we
- don't want to block. The pattern <tt class="LITERAL">.*ads.</tt> e.g.
- catches <span class="QUOTE">"nasty-<span class="emphasis"><i class=
- "EMPHASIS">ads</i></span>.nasty-corp.com"</span> as intended, but
- also <span class="QUOTE">"downlo<span class="emphasis"><i class=
- "EMPHASIS">ads</i></span>.sourcefroge.net"</span> or <span class=
- "QUOTE">"<span class="emphasis"><i class=
- "EMPHASIS">ads</i></span>l.some-provider.net."</span> So here come
- some well-known exceptions to the <tt class="LITERAL">+<a href=
- "actions-file.html#BLOCK">block</a></tt> section above.</p>
-
- <p>Note that these are exceptions to exceptions from the default!
- Consider the URL <span class=
- "QUOTE">"downloads.sourcefroge.net"</span>: Initially, all actions
- are deactivated, so it wouldn't get blocked. Then comes the defaults
- section, which matches the URL, but just deactivates the <tt class=
- "LITERAL"><a href="actions-file.html#BLOCK">block</a></tt> action
- once again. Then it matches <tt class="LITERAL">.*ads.</tt>, an
- exception to the general non-blocking policy, and suddenly <tt class=
- "LITERAL"><a href="actions-file.html#BLOCK">+block</a></tt> applies.
- And now, it'll match <tt class="LITERAL">.*loads.</tt>, where
- <tt class="LITERAL"><a href="actions-file.html#BLOCK">-block</a></tt>
- applies, so (unless it matches <span class="emphasis"><i class=
- "EMPHASIS">again</i></span> further down) it ends up with no
- <tt class="LITERAL"><a href="actions-file.html#BLOCK">block</a></tt>
- action applying.</p>
+ </td>
+ </tr>
+ </table>
- <table border="0" bgcolor="#E0E0E0" width="100%">
- <tr>
- <td>
- <pre class="SCREEN">
+ <p>
+ It's quite remarkable how many advertisers actually call their
+ banner servers ads.<tt class=
+ "REPLACEABLE"><i>company</i></tt>.com, or call the directory in
+ which the banners are stored simply <span class=
+ "QUOTE">"banners"</span>. So the above generic patterns are
+ surprisingly effective.
+ </p>
+ <p>
+ But being very generic, they necessarily also catch URLs that we
+ don't want to block. The pattern <tt class="LITERAL">.*ads.</tt>
+ e.g. catches <span class="QUOTE">"nasty-<span class="emphasis"><i
+ class="EMPHASIS">ads</i></span>.nasty-corp.com"</span> as
+ intended, but also <span class="QUOTE">"downlo<span class=
+ "emphasis"><i class=
+ "EMPHASIS">ads</i></span>.sourcefroge.net"</span> or <span class=
+ "QUOTE">"<span class="emphasis"><i class=
+ "EMPHASIS">ads</i></span>l.some-provider.net."</span> So here
+ come some well-known exceptions to the <tt class="LITERAL">+<a
+ href="actions-file.html#BLOCK">block</a></tt> section above.
+ </p>
+ <p>
+ Note that these are exceptions to exceptions from the default!
+ Consider the URL <span class=
+ "QUOTE">"downloads.sourcefroge.net"</span>: Initially, all
+ actions are deactivated, so it wouldn't get blocked. Then comes
+ the defaults section, which matches the URL, but just deactivates
+ the <tt class="LITERAL"><a href=
+ "actions-file.html#BLOCK">block</a></tt> action once again. Then
+ it matches <tt class="LITERAL">.*ads.</tt>, an exception to the
+ general non-blocking policy, and suddenly <tt class="LITERAL"><a
+ href="actions-file.html#BLOCK">+block</a></tt> applies. And now,
+ it'll match <tt class="LITERAL">.*loads.</tt>, where <tt class=
+ "LITERAL"><a href="actions-file.html#BLOCK">-block</a></tt>
+ applies, so (unless it matches <span class="emphasis"><i class=
+ "EMPHASIS">again</i></span> further down) it ends up with no <tt
+ class="LITERAL"><a href="actions-file.html#BLOCK">block</a></tt>
+ action applying.
+ </p>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="100%">
+ <tr>
+ <td>
+<pre class="SCREEN">
##########################################################################
# Save some innocent victims of the above generic block patterns:
##########################################################################
www.globalintersec.com/adv # (adv = advanced)
www.ugu.com/sui/ugu/adv
</pre>
- </td>
- </tr>
- </table>
-
- <p>Filtering source code can have nasty side effects, so make an
- exception for our friends at sourceforge.net, and all paths with
- <span class="QUOTE">"cvs"</span> in them. Note that <tt class=
- "LITERAL">-<a href="actions-file.html#FILTER">filter</a></tt>
- disables <span class="emphasis"><i class="EMPHASIS">all</i></span>
- filters in one fell swoop!</p>
+ </td>
+ </tr>
+ </table>
- <table border="0" bgcolor="#E0E0E0" width="100%">
- <tr>
- <td>
- <pre class="SCREEN">
+ <p>
+ Filtering source code can have nasty side effects, so make an
+ exception for our friends at sourceforge.net, and all paths with
+ <span class="QUOTE">"cvs"</span> in them. Note that <tt class=
+ "LITERAL">-<a href="actions-file.html#FILTER">filter</a></tt>
+ disables <span class="emphasis"><i class=
+ "EMPHASIS">all</i></span> filters in one fell swoop!
+ </p>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="100%">
+ <tr>
+ <td>
+<pre class="SCREEN">
# Don't filter code!
#
{ -<a href="actions-file.html#FILTER">filter</a> }
wiki.
.sourceforge.net
</pre>
- </td>
- </tr>
- </table>
-
- <p>The actual <tt class="FILENAME">default.action</tt> is of course
- much more comprehensive, but we hope this example made clear how it
- works.</p>
- </div>
-
- <div class="SECT3">
- <h3 class="SECT3"><a name="USER-ACTION" id="USER-ACTION">8.7.3.
- user.action</a></h3>
-
- <p>So far we are painting with a broad brush by setting general
- policies, which would be a reasonable starting point for many people.
- Now, you might want to be more specific and have customized rules
- that are more suitable to your personal habits and preferences. These
- would be for narrowly defined situations like your ISP or your bank,
- and should be placed in <tt class="FILENAME">user.action</tt>, which
- is parsed after all other actions files and hence has the last word,
- over-riding any previously defined actions. <tt class=
- "FILENAME">user.action</tt> is also a <span class=
- "emphasis"><i class="EMPHASIS">safe</i></span> place for your
- personal settings, since <tt class="FILENAME">default.action</tt> is
- actively maintained by the <span class="APPLICATION">Privoxy</span>
- developers and you'll probably want to install updated versions from
- time to time.</p>
-
- <p>So let's look at a few examples of things that one might typically
- do in <tt class="FILENAME">user.action</tt>:</p>
+ </td>
+ </tr>
+ </table>
- <table border="0" bgcolor="#E0E0E0" width="100%">
- <tr>
- <td>
- <pre class="SCREEN">
+ <p>
+ The actual <tt class="FILENAME">default.action</tt> is of course
+ much more comprehensive, but we hope this example made clear how
+ it works.
+ </p>
+ </div>
+ <div class="SECT3">
+ <h3 class="SECT3">
+ <a name="USER-ACTION">8.7.3. user.action</a>
+ </h3>
+ <p>
+ So far we are painting with a broad brush by setting general
+ policies, which would be a reasonable starting point for many
+ people. Now, you might want to be more specific and have
+ customized rules that are more suitable to your personal habits
+ and preferences. These would be for narrowly defined situations
+ like your ISP or your bank, and should be placed in <tt class=
+ "FILENAME">user.action</tt>, which is parsed after all other
+ actions files and hence has the last word, over-riding any
+ previously defined actions. <tt class="FILENAME">user.action</tt>
+ is also a <span class="emphasis"><i class=
+ "EMPHASIS">safe</i></span> place for your personal settings,
+ since <tt class="FILENAME">default.action</tt> is actively
+ maintained by the <span class="APPLICATION">Privoxy</span>
+ developers and you'll probably want to install updated versions
+ from time to time.
+ </p>
+ <p>
+ So let's look at a few examples of things that one might
+ typically do in <tt class="FILENAME">user.action</tt>:
+ </p>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="100%">
+ <tr>
+ <td>
+<pre class="SCREEN">
# My user.action file. <fred@example.com>
</pre>
- </td>
- </tr>
- </table>
-
- <p>As <a href="actions-file.html#ALIASES">aliases</a> are local to
- the actions file that they are defined in, you can't use the ones
- from <tt class="FILENAME">default.action</tt>, unless you repeat them
- here:</p>
+ </td>
+ </tr>
+ </table>
- <table border="0" bgcolor="#E0E0E0" width="100%">
- <tr>
- <td>
- <pre class="SCREEN">
+ <p>
+ As <a href="actions-file.html#ALIASES">aliases</a> are local to
+ the actions file that they are defined in, you can't use the ones
+ from <tt class="FILENAME">default.action</tt>, unless you repeat
+ them here:
+ </p>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="100%">
+ <tr>
+ <td>
+<pre class="SCREEN">
# Aliases are local to the file they are defined in.
# (Re-)define aliases for this file:
#
# Alias for specific file types that are text, but might have conflicting
# MIME types. We want the browser to force these to be text documents.
handle-as-text = -<a href="actions-file.html#FILTER">filter</a> +-<a href=
-"actions-file.html#CONTENT-TYPE-OVERWRITE">content-type-overwrite{text/plain}</a> +-<a href="actions-file.html#FORCE-TEXT-MODE">force-text-mode</a> -<a href="actions-file.html#HIDE-CONTENT-DISPOSITION">hide-content-disposition</a>
+"actions-file.html#CONTENT-TYPE-OVERWRITE">content-type-overwrite{text/plain}</a> +-<a
+ href="actions-file.html#FORCE-TEXT-MODE">force-text-mode</a> -<a href=
+"actions-file.html#HIDE-CONTENT-DISPOSITION">hide-content-disposition</a>
</pre>
- </td>
- </tr>
- </table>
-
- <p>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 <tt class=
- "LITERAL">allow-all-cookies</tt> alias defined above does exactly
- that, i.e. it disables crunching of cookies in any direction, and the
- processing of cookies to make them only temporary.</p>
-
- <table border="0" bgcolor="#E0E0E0" width="100%">
- <tr>
- <td>
- <pre class="SCREEN">
+ </td>
+ </tr>
+ </table>
+ <br>
+
+ <p>
+ 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 <tt class=
+ "LITERAL">allow-all-cookies</tt> alias defined above does exactly
+ that, i.e. it disables crunching of cookies in any direction, and
+ the processing of cookies to make them only temporary.
+ </p>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="100%">
+ <tr>
+ <td>
+<pre class="SCREEN">
{ allow-all-cookies }
sourceforge.net
.yahoo.com
.msdn.microsoft.com
.redhat.com
</pre>
- </td>
- </tr>
- </table>
-
- <p>Your bank is allergic to some filter, but you don't know which, so
- you disable them all:</p>
+ </td>
+ </tr>
+ </table>
- <table border="0" bgcolor="#E0E0E0" width="100%">
- <tr>
- <td>
- <pre class="SCREEN">
+ <p>
+ Your bank is allergic to some filter, but you don't know which,
+ so you disable them all:
+ </p>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="100%">
+ <tr>
+ <td>
+<pre class="SCREEN">
{ -<a href="actions-file.html#FILTER">filter</a> }
.your-home-banking-site.com
</pre>
- </td>
- </tr>
- </table>
-
- <p>Some file types you may not want to filter for various
- reasons:</p>
+ </td>
+ </tr>
+ </table>
- <table border="0" bgcolor="#E0E0E0" width="100%">
- <tr>
- <td>
- <pre class="SCREEN">
+ <p>
+ Some file types you may not want to filter for various reasons:
+ </p>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="100%">
+ <tr>
+ <td>
+<pre class="SCREEN">
# Technical documentation is likely to contain strings that might
# erroneously get altered by the JavaScript-oriented filters:
#
#
stupid-server.example.com/
</pre>
- </td>
- </tr>
- </table>
-
- <p>Example of a simple <a href="actions-file.html#BLOCK">block</a>
- action. Say you've seen an ad on your favourite page on example.com
- that you want to get rid of. You have right-clicked the image,
- selected <span class="QUOTE">"copy image location"</span> and pasted
- the URL below while removing the leading http://, into a <tt class=
- "LITERAL">{ +block{} }</tt> section. Note that <tt class="LITERAL">{
- +handle-as-image }</tt> need not be specified, since all URLs ending
- in <tt class="LITERAL">.gif</tt> will be tagged as images by the
- general rules as set in default.action anyway:</p>
+ </td>
+ </tr>
+ </table>
- <table border="0" bgcolor="#E0E0E0" width="100%">
- <tr>
- <td>
- <pre class="SCREEN">
+ <p>
+ Example of a simple <a href="actions-file.html#BLOCK">block</a>
+ action. Say you've seen an ad on your favourite page on
+ example.com that you want to get rid of. You have right-clicked
+ the image, selected <span class="QUOTE">"copy image
+ location"</span> and pasted the URL below while removing the
+ leading http://, into a <tt class="LITERAL">{ +block{} }</tt>
+ section. Note that <tt class="LITERAL">{ +handle-as-image }</tt>
+ need not be specified, since all URLs ending in <tt class=
+ "LITERAL">.gif</tt> will be tagged as images by the general rules
+ as set in default.action anyway:
+ </p>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="100%">
+ <tr>
+ <td>
+<pre class="SCREEN">
{ +<a href="actions-file.html#BLOCK">block</a>{Nasty ads.} }
www.example.com/nasty-ads/sponsor\.gif
another.example.net/more/junk/here/
</pre>
- </td>
- </tr>
- </table>
-
- <p>The URLs of dynamically generated banners, especially from large
- banner farms, often don't use the well-known image file name
- extensions, which makes it impossible for <span class=
- "APPLICATION">Privoxy</span> to guess the file type just by looking
- at the URL. You can use the <tt class="LITERAL">+block-as-image</tt>
- alias defined above for these cases. Note that objects which match
- this rule but then turn out NOT to be an image are typically rendered
- as a <span class="QUOTE">"broken image"</span> icon by the browser.
- Use cautiously.</p>
+ </td>
+ </tr>
+ </table>
- <table border="0" bgcolor="#E0E0E0" width="100%">
- <tr>
- <td>
- <pre class="SCREEN">
+ <p>
+ The URLs of dynamically generated banners, especially from large
+ banner farms, often don't use the well-known image file name
+ extensions, which makes it impossible for <span class=
+ "APPLICATION">Privoxy</span> to guess the file type just by
+ looking at the URL. You can use the <tt class=
+ "LITERAL">+block-as-image</tt> alias defined above for these
+ cases. Note that objects which match this rule but then turn out
+ NOT to be an image are typically rendered as a <span class=
+ "QUOTE">"broken image"</span> icon by the browser. Use
+ cautiously.
+ </p>
+ <p>
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="100%">
+ <tr>
+ <td>
+<pre class="SCREEN">
{ +block-as-image }
.doubleclick.net
.fastclick.net
/Realmedia/ads/
ar.atwola.com/
</pre>
- </td>
- </tr>
- </table>
-
- <p>Now you noticed that the default configuration breaks Forbes
- Magazine, but you were too lazy to find out which action is the
- culprit, and you were again too lazy to give <a href=
- "contact.html">feedback</a>, so you just used the <tt class=
- "LITERAL">fragile</tt> alias on the site, and -- <span class=
- "emphasis"><i class="EMPHASIS">whoa!</i></span> -- it worked. The
- <tt class="LITERAL">fragile</tt> aliases disables those actions that
- are most likely to break a site. Also, good for testing purposes to
- see if it is <span class="APPLICATION">Privoxy</span> that is causing
- the problem or not. We later find other regular sites that misbehave,
- and add those to our personalized list of troublemakers:</p>
+ </td>
+ </tr>
+ </table>
- <table border="0" bgcolor="#E0E0E0" width="100%">
- <tr>
- <td>
- <pre class="SCREEN">
+ <p>
+ Now you noticed that the default configuration breaks Forbes
+ Magazine, but you were too lazy to find out which action is the
+ culprit, and you were again too lazy to give <a href=
+ "contact.html">feedback</a>, so you just used the <tt class=
+ "LITERAL">fragile</tt> alias on the site, and -- <span class=
+ "emphasis"><i class="EMPHASIS">whoa!</i></span> -- it worked. The
+ <tt class="LITERAL">fragile</tt> aliases disables those actions
+ that are most likely to break a site. Also, good for testing
+ purposes to see if it is <span class="APPLICATION">Privoxy</span>
+ that is causing the problem or not. We later find other regular
+ sites that misbehave, and add those to our personalized list of
+ troublemakers:
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="100%">
+ <tr>
+ <td>
+<pre class="SCREEN">
{ fragile }
.forbes.com
webmail.example.com
.mybank.com
</pre>
- </td>
- </tr>
- </table>
-
- <p>You like the <span class="QUOTE">"fun"</span> text replacements in
- <tt class="FILENAME">default.filter</tt>, but it is disabled in the
- distributed actions file. So you'd like to turn it on in your
- private, update-safe config, once and for all:</p>
+ </td>
+ </tr>
+ </table>
- <table border="0" bgcolor="#E0E0E0" width="100%">
- <tr>
- <td>
- <pre class="SCREEN">
+ <p>
+ You like the <span class="QUOTE">"fun"</span> text replacements
+ in <tt class="FILENAME">default.filter</tt>, but it is disabled
+ in the distributed actions file. So you'd like to turn it on in
+ your private, update-safe config, once and for all:
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="100%">
+ <tr>
+ <td>
+<pre class="SCREEN">
{ +<a href="actions-file.html#FILTER-FUN">filter{fun}</a> }
/ # For ALL sites!
</pre>
- </td>
- </tr>
- </table>
-
- <p>Note that the above is not really a good idea: There are
- exceptions to the filters in <tt class="FILENAME">default.action</tt>
- for things that really shouldn't be filtered, like code on
- CVS->Web interfaces. Since <tt class="FILENAME">user.action</tt>
- has the last word, these exceptions won't be valid for the
- <span class="QUOTE">"fun"</span> filtering specified here.</p>
-
- <p>You might also worry about how your favourite free websites are
- funded, and find that they rely on displaying banner advertisements
- to survive. So you might want to specifically allow banners for those
- sites that you feel provide value to you:</p>
+ </td>
+ </tr>
+ </table>
- <table border="0" bgcolor="#E0E0E0" width="100%">
- <tr>
- <td>
- <pre class="SCREEN">
+ <p>
+ Note that the above is not really a good idea: There are
+ exceptions to the filters in <tt class=
+ "FILENAME">default.action</tt> for things that really shouldn't
+ be filtered, like code on CVS->Web interfaces. Since <tt
+ class="FILENAME">user.action</tt> has the last word, these
+ exceptions won't be valid for the <span class=
+ "QUOTE">"fun"</span> filtering specified here.
+ </p>
+ <p>
+ You might also worry about how your favourite free websites are
+ funded, and find that they rely on displaying banner
+ advertisements to survive. So you might want to specifically
+ allow banners for those sites that you feel provide value to you:
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="100%">
+ <tr>
+ <td>
+<pre class="SCREEN">
{ allow-ads }
.sourceforge.net
.slashdot.org
.osdn.net
</pre>
- </td>
- </tr>
- </table>
-
- <p>Note that <tt class="LITERAL">allow-ads</tt> has been aliased to
- <tt class="LITERAL">-<a href=
- "actions-file.html#BLOCK">block</a></tt>, <tt class=
- "LITERAL">-<a href=
- "actions-file.html#FILTER-BANNERS-BY-SIZE">filter{banners-by-size}</a></tt>,
- and <tt class="LITERAL">-<a href=
- "actions-file.html#FILTER-BANNERS-BY-LINK">filter{banners-by-link}</a></tt>
- above.</p>
-
- <p>Invoke another alias here to force an over-ride of the MIME type
- <tt class="LITERAL">application/x-sh</tt> which typically would open
- a download type dialog. In my case, I want to look at the shell
- script, and then I can save it should I choose to.</p>
+ </td>
+ </tr>
+ </table>
- <table border="0" bgcolor="#E0E0E0" width="100%">
- <tr>
- <td>
- <pre class="SCREEN">
+ <p>
+ Note that <tt class="LITERAL">allow-ads</tt> has been aliased to
+ <tt class="LITERAL">-<a href=
+ "actions-file.html#BLOCK">block</a></tt>, <tt class="LITERAL">-<a
+ href=
+ "actions-file.html#FILTER-BANNERS-BY-SIZE">filter{banners-by-size}</a></tt>,
+ and <tt class="LITERAL">-<a href=
+ "actions-file.html#FILTER-BANNERS-BY-LINK">filter{banners-by-link}</a></tt>
+ above.
+ </p>
+ <p>
+ Invoke another alias here to force an over-ride of the MIME type
+ <tt class="LITERAL">application/x-sh</tt> which typically would
+ open a download type dialog. In my case, I want to look at the
+ shell script, and then I can save it should I choose to.
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="100%">
+ <tr>
+ <td>
+<pre class="SCREEN">
{ handle-as-text }
/.*\.sh$
</pre>
- </td>
- </tr>
- </table>
-
- <p><tt class="FILENAME">user.action</tt> is generally the best place
- to define exceptions and additions to the default policies of
- <tt class="FILENAME">default.action</tt>. Some actions are safe to
- have their default policies set here though. So let's set a default
- policy to have a <span class="QUOTE">"blank"</span> image as opposed
- to the checkerboard pattern for <span class="emphasis"><i class=
- "EMPHASIS">ALL</i></span> sites. <span class="QUOTE">"/"</span> of
- course matches all URL paths and patterns:</p>
+ </td>
+ </tr>
+ </table>
- <table border="0" bgcolor="#E0E0E0" width="100%">
- <tr>
- <td>
- <pre class="SCREEN">
+ <p>
+ <tt class="FILENAME">user.action</tt> is generally the best place
+ to define exceptions and additions to the default policies of <tt
+ class="FILENAME">default.action</tt>. Some actions are safe to
+ have their default policies set here though. So let's set a
+ default policy to have a <span class="QUOTE">"blank"</span> image
+ as opposed to the checkerboard pattern for <span class=
+ "emphasis"><i class="EMPHASIS">ALL</i></span> sites. <span class=
+ "QUOTE">"/"</span> of course matches all URL paths and patterns:
+ </p>
+ <table border="0" bgcolor="#E0E0E0" width="100%">
+ <tr>
+ <td>
+<pre class="SCREEN">
{ +<a href=
"actions-file.html#SET-IMAGE-BLOCKER">set-image-blocker{blank}</a> }
/ # ALL sites
</pre>
- </td>
- </tr>
- </table>
+ </td>
+ </tr>
+ </table>
+ </div>
</div>
</div>
- </div>
-
- <div class="NAVFOOTER">
- <hr align="left" width="100%">
-
- <table summary="Footer navigation table" width="100%" border="0"
- cellpadding="0" cellspacing="0">
- <tr>
- <td width="33%" align="left" valign="top"><a href="config.html"
- accesskey="P">Prev</a></td>
-
- <td width="34%" align="center" valign="top"><a href="index.html"
- accesskey="H">Home</a></td>
-
- <td width="33%" align="right" valign="top"><a href="filter-file.html"
- accesskey="N">Next</a></td>
- </tr>
-
- <tr>
- <td width="33%" align="left" valign="top">The Main Configuration
- File</td>
-
- <td width="34%" align="center" valign="top"> </td>
-
- <td width="33%" align="right" valign="top">Filter Files</td>
- </tr>
- </table>
- </div>
-</body>
+ <div class="NAVFOOTER">
+ <hr align="LEFT" width="100%">
+ <table summary="Footer navigation table" width="100%" border="0"
+ cellpadding="0" cellspacing="0">
+ <tr>
+ <td width="33%" align="left" valign="top">
+ <a href="config.html" accesskey="P">Prev</a>
+ </td>
+ <td width="34%" align="center" valign="top">
+ <a href="index.html" accesskey="H">Home</a>
+ </td>
+ <td width="33%" align="right" valign="top">
+ <a href="filter-file.html" accesskey="N">Next</a>
+ </td>
+ </tr>
+ <tr>
+ <td width="33%" align="left" valign="top">
+ The Main Configuration File
+ </td>
+ <td width="34%" align="center" valign="top">
+
+ </td>
+ <td width="33%" align="right" valign="top">
+ Filter Files
+ </td>
+ </tr>
+ </table>
+ </div>
+ </body>
</html>
+