<!entity p-authors SYSTEM "p-authors.sgml">
<!entity config SYSTEM "p-config.sgml">
<!entity changelog SYSTEM "changelog.sgml">
-<!entity p-version "3.0.21">
-<!entity p-status "stable">
+<!entity p-version "3.0.25">
+<!entity p-status "UNRELEASED">
<!entity % p-authors-formal "INCLUDE"> <!-- include additional text, etc -->
-<!entity % p-not-stable "IGNORE">
-<!entity % p-stable "INCLUDE">
+<!entity % p-not-stable "INCLUDE">
+<!entity % p-stable "IGNORE">
<!entity % p-text "IGNORE"> <!-- define we are not a text only doc -->
<!entity % p-doc "INCLUDE"> <!-- and we are a formal doc -->
<!entity % p-readme "IGNORE">
This file belongs into
ijbswa.sourceforge.net:/home/groups/i/ij/ijbswa/htdocs/
- $Id: user-manual.sgml,v 2.176 2013/11/24 14:27:09 fabiankeil Exp $
+ $Id: user-manual.sgml,v 2.206 2016/03/17 10:43:07 fabiankeil Exp $
- Copyright (C) 2001-2013 Privoxy Developers http://www.privoxy.org/
+ Copyright (C) 2001-2014 Privoxy Developers http://www.privoxy.org/
See LICENSE.
========================================================================
<subscript>
<!-- Completely the wrong markup, but very little is allowed -->
<!-- in this part of an article. FIXME -->
- <link linkend="copyright">Copyright</link> &my-copy; 2001-2013 by
+ <link linkend="copyright">Copyright</link> &my-copy; 2001-2014 by
<ulink url="http://www.privoxy.org/">Privoxy Developers</ulink>
</subscript>
</pubdate>
-<pubdate>$Id: user-manual.sgml,v 2.176 2013/11/24 14:27:09 fabiankeil Exp $</pubdate>
+<pubdate>$Id: user-manual.sgml,v 2.206 2016/03/17 10:43:07 fabiankeil Exp $</pubdate>
<!--
</para>
</listitem>
-<!--
- Did anyone test these lately?
- fk 2007-11-10
- <listitem>
- <para>
- For easy access to &my-app;'s most important controls, drag the provided
- <link linkend="bookmarklets">Bookmarklets</link> into your browser's
- personal toolbar.
- </para>
- </listitem>
--->
-
<listitem>
<para>
Please see the section <link linkend="contact">Contacting the
</para>
</sect2>
+<sect2 id="start-freebsd">
+<title>FreeBSD and ElectroBSD</title>
+<para>
+ To start <application>Privoxy</application> upon booting, add
+ "privoxy_enable='YES'" to <filename>/etc/rc.conf</filename>.
+ <application>Privoxy</application> will use
+ <filename>/usr/local/etc/privoxy/config</filename> as its main
+ configuration file.
+</para>
+<para>
+ If you installed <application>Privoxy</application> into a jail, the
+ paths above are relative to the jail root.
+</para>
+<para>
+ To start <application>Privoxy</application> manually, run:
+</para>
+<para>
+ <screen>
+ # service privoxy onestart
+</screen>
+</para>
+</sect2>
+
<sect2 id="start-windows">
<title>Windows</title>
<para>
</sect2>
<sect2 id="start-unices">
-<title>Solaris, NetBSD, FreeBSD, HP-UX and others</title>
+<title>Generic instructions for Unix derivates (Solaris, NetBSD, HP-UX etc.)</title>
<para>
Example Unix startup command:
</para>
<para>
<screen>
- # /usr/sbin/privoxy /etc/privoxy/config
+ # /usr/sbin/privoxy --user privoxy /etc/privoxy/config
</screen>
</para>
+<para>
+ Note that if you installed <application>Privoxy</application> through
+ a package manager, the package will probably contain a platform-specific
+ script or configuration file to start <application>Privoxy</application>
+ upon boot.
+</para>
</sect2>
<sect2 id="start-os2">
<sect2 id="start-macosx">
<title>Mac OS X</title>
<para>
- After downloading the privoxy software, unzip the downloaded file by
- double-clicking on the zip file icon. Then, double-click on the
- installer package icon and follow the installation process.
-</para>
-<para>
- The privoxy service will automatically start after a successful
- installation. In addition, the privoxy service will automatically
- start every time your computer starts up.
-</para>
-<para>
- To prevent the privoxy service from automatically starting when your
- computer starts up, remove or rename the folder named
- /Library/StartupItems/Privoxy.
-</para>
-<para>
- A simple application named Privoxy Utility has been created which
- enables administrators to easily start and stop the privoxy service.
+ The privoxy service will automatically start after a successful installation
+ (and thereafter every time your computer starts up) however you will need to
+ configure your web browser(s) to use it. To do so, configure them to use a
+ proxy for HTTP and HTTPS at the address 127.0.0.1:8118.
</para>
<para>
- In addition, the Privoxy Utility presents a simple way for
- administrators to edit the various privoxy config files. A method
- to uninstall the software is also available.
+ To prevent the privoxy service from automatically starting when your computer
+ starts up, remove or rename the file <literal>/Library/LaunchDaemons/org.ijbswa.privoxy.plist</literal>
+ (on OS X 10.5 and higher) or the folder named
+ <literal>/Library/StartupItems/Privoxy</literal> (on OS X 10.4 'Tiger').
</para>
<para>
- An administrator username and password must be supplied in order for
- the Privoxy Utility to perform any of the tasks.
+ To manually start or stop the privoxy service, use the scripts startPrivoxy.sh
+ and stopPrivoxy.sh supplied in /Applications/Privoxy. They must be run from an
+ administrator account, using sudo.
</para>
</sect2>
<!-- ~~~~~ New section ~~~~~ -->
-<sect2>
+<sect2 id="control-with-webbrowser">
<title>Controlling Privoxy with Your Web Browser</title>
<para>
<application>Privoxy</application>'s user interface can be reached through the special
it as a test to see whether it is <application>Privoxy</application>
causing the problem or not. <application>Privoxy</application> continues
to run as a proxy in this case, but all manipulation is disabled, i.e.
- <application>Privoxy</application> acts like a normal forwarding proxy. There
- is even a toggle <link linkend="bookmarklets">Bookmarklet</link> offered, so
- that you can toggle <application>Privoxy</application> with one click from
- your browser.
+ <application>Privoxy</application> acts like a normal forwarding proxy.
</para>
<para>
</para>
<!-- ~~~~~ New section ~~~~~ -->
-<sect2>
+<sect2 id="right-mix">
<title>Finding the Right Mix</title>
<para>
Note that some <link linkend="actions">actions</link>, like cookie suppression
</sect2>
<!-- ~~~~~ New section ~~~~~ -->
-<sect2>
+<sect2 id="how-to-edit">
<title>How to Edit</title>
<para>
The easiest way to edit the actions files is with a browser by
<para>
Generally, an URL pattern has the form
- <literal><domain><port>/<path></literal>, where the
- <literal><domain></literal>, the <literal><port></literal>
+ <literal><host><port>/<path></literal>, where the
+ <literal><host></literal>, the <literal><port></literal>
and the <literal><path></literal> are optional. (This is why the special
<literal>/</literal> pattern matches all URLs). Note that the protocol
portion of the URL pattern (e.g. <literal>http://</literal>) should
<emphasis>not</emphasis> be included in the pattern. This is assumed already!
</para>
<para>
- The pattern matching syntax is different for the domain and path parts of
- the URL. The domain part uses a simple globbing type matching technique,
+ 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
<ulink url="http://en.wikipedia.org/wiki/Regular_expressions"><quote>Regular
Expressions</quote></ulink> (POSIX 1003.2).
</para>
<para>
The port part of a pattern is a decimal port number preceded by a colon
- (<literal>:</literal>). If the domain part contains a numerical IPv6 address,
+ (<literal>:</literal>). If the host part contains a numerical IPv6 address,
it has to be put into angle brackets
(<literal><</literal>, <literal>></literal>).
</para>
<term><literal>www.example.com/</literal></term>
<listitem>
<para>
- is a domain-only pattern and will match any request to <literal>www.example.com</literal>,
+ is a host-only pattern and will match any request to <literal>www.example.com</literal>,
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 <literal>example.com</literal> is different and would NOT match.
<term><literal>www.example.com</literal></term>
<listitem>
<para>
- means exactly the same. For domain-only patterns, the trailing <literal>/</literal> may
+ means exactly the same. For host-only patterns, the trailing <literal>/</literal> may
be omitted.
</para>
</listitem>
</para>
</listitem>
</varlistentry>
+ <varlistentry>
+ <term><literal>10.0.0.1/</literal></term>
+ <listitem>
+ <para>
+ Matches any URL with the host address <literal>10.0.0.1</literal>.
+ (Note that the real URL uses plain brackets, not angle brackets.)
+ </para>
+ </listitem>
+ </varlistentry>
<varlistentry>
<term><literal><2001:db8::1>/</literal></term>
<listitem>
<!-- ~~~~~ New section ~~~~~ -->
-<sect3><title>The Domain Pattern</title>
+<sect3 id="host-pattern"><title>The Host Pattern</title>
<para>
- The matching of the domain part offers some flexible options: if the
- domain starts or ends with a dot, it becomes unanchored at that end.
+ 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:
</para>
<!-- ~~~~~ New section ~~~~~ -->
-<sect3><title>The Path Pattern</title>
+<sect3 id="path-pattern"><title>The Path Pattern</title>
<para>
<application>Privoxy</application> uses <quote>modern</quote> POSIX 1003.2
<!-- ~~~~~ New section ~~~~~ -->
-<sect3 id="tag-pattern"><title>The Tag Pattern</title>
+<sect3 id="tag-pattern"><title>The Request Tag Pattern</title>
<para>
- Tag patterns are used to change the applying actions based on the
- request's tags. Tags can be created with either the
- <link linkend="CLIENT-HEADER-TAGGER">client-header-tagger</link>
+ 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 <link linkend="CLIENT-HEADER-TAGGER">client-header-tagger</link>
or the <link linkend="SERVER-HEADER-TAGGER">server-header-tagger</link> action.
</para>
<para>
- Tag patterns have to start with <quote>TAG:</quote>, so &my-app;
- can tell them apart from URL patterns. Everything after the colon
+ Request tag patterns have to start with <quote>TAG:</quote>, so &my-app;
+ 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 (&my-app; doesn't silently add a <quote>^</quote>,
</para>
<para>
- Sections can contain URL and tag patterns at the same time,
- but tag patterns are checked after the URL patterns and thus
+ 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.
</para>
<para>
- Once a new tag is added, Privoxy checks right away if it's matched by one
- of the tag patterns and updates the action settings accordingly. As a result
- tags can be used to activate other tagger actions, as long as these other
+ 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.
</para>
</sect3>
<!-- ~~~~~ New section ~~~~~ -->
-<sect3 id="negative-tag-patterns"><title>The Negative Tag Patterns</title>
+<sect3 id="negative-tag-patterns"><title>The Negative Request Tag Patterns</title>
<para>
- To match requests that do not have a certain tag, specify a negative tag pattern
+ To match requests that do not have a certain request tag, specify a negative tag pattern
by prefixing the tag pattern line with either <quote>NO-REQUEST-TAG:</quote>
or <quote>NO-RESPONSE-TAG:</quote> instead of <quote>TAG:</quote>.
</para>
<para>
- Negative tag patterns created with <quote>NO-REQUEST-TAG:</quote> are checked
+ Negative request tag patterns created with <quote>NO-REQUEST-TAG:</quote> are checked
after all client headers are scanned, the ones created with <quote>NO-RESPONSE-TAG:</quote>
are checked after all server headers are scanned. In both cases all the created
tags are considered.
</para>
+<!-- ~~~~~ New section ~~~~~ -->
+<sect3 id="client-tag-pattern"><title>The Client Tag Pattern</title>
+
+<!-- XXX: This section contains duplicates content from the
+ client-specific-tag documentation. -->
+
+<warning>
+<para>
+ This is an experimental feature. The syntax is likely to change in future versions.
+</para>
+</warning>
+
+<para>
+ 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.
+</para>
+
+<para>
+ After a client-specific tag has been defined with the
+ <link linkend="client-specific-tag">client-specific-tag</link>,
+ 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!
+</para>
+<para>
+ 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.
+</para>
+<para>
+ Clients can request tags to be set by using the CGI interface <ulink
+ url="http://config.privoxy.org/show-client-tags">http://config.privoxy.org/show-client-tags</ulink>.
+</para>
+
+<para>
+ Example:
+</para>
+
+<para>
+ <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</screen>
+</para>
</sect2>
<term>Example usage:</term>
<listitem>
<para>
- <screen>+add-header{X-User-Tracking: sucks}</screen>
+ <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}}
+/</screen>
</para>
</listitem>
</varlistentry>
<term>Type:</term>
<!-- boolean, parameterized, Multi-value -->
<listitem>
- <para>Parameterized.</para>
+ <para>Multi-value.</para>
</listitem>
</varlistentry>
<term>Type:</term>
<!-- boolean, parameterized, Multi-value -->
<listitem>
- <para>Parameterized.</para>
+ <para>Multi-value.</para>
</listitem>
</varlistentry>
</variablelist>
</sect3>
+<!-- ~~~~~ New section ~~~~~ -->
+<sect3 renderas="sect4" id="external-filter">
+<title>external-filter</title>
+
+<variablelist>
+ <varlistentry>
+ <term>Typical use:</term>
+ <listitem>
+ <para>Modify content using a programming language of your choice.</para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>Effect:</term>
+ <listitem>
+ <para>
+ 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 <literal>text/plain</literal> MIME type for all files
+ whose type they don't know.)
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>Type:</term>
+ <!-- boolean, parameterized, Multi-value -->
+ <listitem>
+ <para>Multi-value.</para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>Parameter:</term>
+ <listitem>
+ <para>
+ The name of an external content filter, as defined in the
+ <link linkend="filter-file">filter file</link>.
+ External filters can be defined in one or more files as defined by the
+ <literal><link linkend="filterfile">filterfile</link></literal>
+ option in the <link linkend="config">config file</link>.
+ </para>
+ <para>
+ When used in its negative form,
+ and without parameters, <emphasis>all</emphasis> filtering with external
+ filters is completely disabled.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>Notes:</term>
+ <listitem>
+ <para>
+ External filters are scripts or programs that can modify the content in
+ case common <literal><link linkend="filter">filters</link></literal>
+ aren't powerful enough. With the exception that this action doesn't
+ use pcrs-based filters, the notes in the
+ <literal><link linkend="filter">filter</link></literal> section apply.
+ </para>
+ <warning>
+ <para>
+ Currently external filters are executed with &my-app;'s privileges.
+ Only use external filters you understand and trust.
+ </para>
+ </warning>
+ <para>
+ This feature is experimental, the <literal><link
+ linkend="external-filter-syntax">syntax</link></literal>
+ may change in the future.
+ </para>
+
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>Example usage:</term>
+ <listitem>
+ <para>
+ <screen>+external-filter{fancy-filter}</screen>
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</sect3>
+
<!-- ~~~~~ New section ~~~~~ -->
<sect3 renderas="sect4" id="fast-redirects">
<title>fast-redirects</title>
<term>Type:</term>
<!-- boolean, parameterized, Multi-value -->
<listitem>
- <para>Parameterized.</para>
+ <para>Multi-value.</para>
</listitem>
</varlistentry>
<term>Type:</term>
<!-- Boolean, Parameterized, Multi-value -->
<listitem>
- <para>Multi-value.</para>
+ <para>Parameterized.</para>
</listitem>
</varlistentry>
for socks5 connections (with remote DNS resolution).
</para>
</listitem>
+ <listitem>
+ <para>
+ <quote>forward-webserver 127.0.0.1:80</quote> to use the HTTP
+ server listening at 127.0.0.1 port 80 without adjusting the
+ request headers.
+ </para>
+ <para>
+ This makes it more convenient to use Privoxy to make
+ existing websites available as onion services as well.
+ </para>
+ <para>
+ 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.
+ </para>
+ <para>
+ 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.
+ </para>
+ <para>
+ 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.
+ </para>
+ </listitem>
</itemizedlist>
</listitem>
</varlistentry>
<para>
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.
+ to exit. Due to design limitations, invalid parameter syntax isn't detected until the
+ action is used the first time.
</para>
<para>
Use the <ulink url="http://config.privoxy.org/show-url-info">show-url-info CGI page</ulink>
<listitem>
<para>
<screen>
-# Always use direct connections for requests previously tagged as
+# Use an ssh tunnel for requests previously tagged as
# <quote>User-Agent: fetch libfetch/2.0</quote> and make sure
# resuming downloads continues to work.
+#
# This way you can continue to use Tor for your normal browsing,
# without overloading the Tor network with your FreeBSD ports updates
# or downloads of bigger files like ISOs.
+#
# Note that HTTP headers are easy to fake and therefore their
# values are as (un)trustworthy as your clients and users.
-{+forward-override{forward .} \
+{+forward-override{forward-socks5 10.0.0.2:2222 .} \
-hide-if-modified-since \
-overwrite-last-modified \
}
<link linkend="filter-file">filter file</link> section.
</para>
<para>
- This action will be ignored if you use it together with
- <literal><link linkend="block">block</link></literal>.
- It can be combined with
+ Requests can't be blocked and redirected at the same time,
+ applying this action together with
+ <literal><link linkend="block">block</link></literal>
+ 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.
+ </para>
+ <para>
+ This action can be combined with
<literal><link linkend="fast-redirects">fast-redirects{check-decoded-url}</link></literal>
to redirect to a decoded version of a rewritten URL.
</para>
{+redirect{s@^http://[^/]*/results\.aspx\?q=([^&]*).*@http://search.yahoo.com/search?p=$1@}}
search.msn.com//results\.aspx\?q=
+# Redirect http://example.com/&bla=fasel&toChange=foo (and any other value but "bar")
+# to http://example.com/&bla=fasel&toChange=bar
+#
+# The URL pattern makes sure that the following request isn't redirected again.
+{+redirect{s@toChange=[^&]+@toChange=bar@}}
+example.com/.*toChange=(?!bar)
+
+# Add a shortcut to look up illumos bugs
+{+redirect{s@^http://i([0-9]+)/.*@https://www.illumos.org/issues/$1@}}
+# Redirected URL = http://i4974/
+# Redirect Destination = https://www.illumos.org/issues/4974
+i[0-9][0-9][0-9][0-9]*/
+
# Redirect remote requests for this manual
# to the local version delivered by Privoxy
{+redirect{s@^http://www@http://config@}}
<term>Type:</term>
<!-- boolean, parameterized, Multi-value -->
<listitem>
- <para>Parameterized.</para>
+ <para>Multi-value.</para>
</listitem>
</varlistentry>
<term>Type:</term>
<!-- boolean, parameterized, Multi-value -->
<listitem>
- <para>Parameterized.</para>
+ <para>Multi-value.</para>
</listitem>
</varlistentry>
# Tag every request with the content type declared by the server
{+server-header-tagger{content-type}}
/
+
+# If the response has a tag starting with 'image/' enable an external
+# filter that only applies to images.
+#
+# Note that the filter is not available by default, it's just a
+# <literal><link linkend="external-filter-syntax">silly example</link></literal>.
+{+external-filter{rotate-image} +force-text-mode}
+TAG:^image/
</screen>
</para>
</listitem>
<!-- ~~~~~ New section ~~~~~ -->
-<sect3>
+<sect3 id="summary">
<title>Summary</title>
<para>
Note that many of these actions have the potential to cause a page to
and <filename>user.action</filename> file and see how all these pieces come together:
</para>
-<sect3>
+<sect3 id="match-all">
<title>match-all.action</title>
<para>
Remember <emphasis>all actions are disabled when matching starts</emphasis>,
</para>
</sect3>
-<sect3>
+<sect3 id="default-action">
<title>default.action</title>
<para>
</sect3>
-<sect3><title>user.action</title>
+<sect3 id="user-action"><title>user.action</title>
<para>
So far we are painting with a broad brush by setting general policies,
</para>
<para>
- &my-app; supports three different filter actions:
+ &my-app; supports three different pcrs-based filter actions:
<literal><link linkend="filter">filter</link></literal> to
rewrite the content that is send to the client,
<literal><link linkend="client-header-filter">client-header-filter</link></literal>
applying actions through sections with <link linkend="tag-pattern">tag-patterns</link>.
</para>
+<para>
+ Finally &my-app; supports the
+ <literal><link linkend="external-filter">external-filter</link></literal> action
+ to enable <literal><link linkend="external-filter-syntax">external filters</link></literal>
+ written in proper programming languages.
+</para>
+
<para>
Multiple filter files can be defined through the <literal> <link
in a syntax that imitates <ulink url="http://www.perl.org/">Perl</ulink>'s
<literal>s///</literal> operator. If you are familiar with Perl, you
will find this to be quite intuitive, and may want to look at the
- PCRS documentation for the subtle differences to Perl behaviour. Most
- notably, the non-standard option letter <literal>U</literal> is supported,
- which turns the default to ungreedy matching.
+ PCRS documentation for the subtle differences to Perl behaviour.
+</para>
+
+<para>
+ Most notably, the non-standard option letter <literal>U</literal> is supported,
+ which turns the default to ungreedy matching (add <literal>?</literal> to
+ quantifiers to turn them greedy again).
+</para>
+
+<para>
+ The non-standard option letter <literal>D</literal> (dynamic) allows
+ to use the variables $host, $origin (the IP address the request came from),
+ $path and $url. They will be replaced with the value they refer to before
+ the filter is executed.
+</para>
+
+<para>
+ Note that '$' is a bad choice for a delimiter in a dynamic filter as you
+ might end up with unintended variables if you use a variable name
+ directly after the delimiter. Variables will be resolved without
+ escaping anything, therefore you also have to be careful not to chose
+ delimiters that appear in the replacement text. For example '<' should
+ be save, while '?' will sooner or later cause conflicts with $url.
+</para>
+
+<para>
+ The non-standard option letter <literal>T</literal> (trivial) prevents
+ parsing for backreferences in the substitute. Use it if you want to include
+ text like '$&' in your substitute without quoting.
</para>
<para>
<!-- ~~~~~~~~ New section Header ~~~~~~~~~ -->
-<sect2><title>Filter File Tutorial</title>
+<sect2 id="filter-file-tut"><title>Filter File Tutorial</title>
<para>
Now, let's complete our <quote>foo</quote> content filter. We have already defined
the heading, but the jobs are still missing. Since all it does is to replace
</variablelist>
</sect2>
+
+<!-- ~~~~~~~~ New section Header ~~~~~~~~~ -->
+<sect2 id="external-filter-syntax"><title>External filter syntax</title>
+<para>
+ External filters are scripts or programs that can modify the content in
+ case common <literal><link linkend="filter">filters</link></literal>
+ aren't powerful enough.
+</para>
+<para>
+ External filters can be written in any language the platform &my-app; runs
+ on supports.
+</para>
+<para>
+ They are controlled with the
+ <literal><link linkend="external-filter">external-filter</link></literal> action
+ and have to be defined in the <literal><link linkend="filterfile">filterfile</link></literal>
+ first.
+</para>
+<para>
+ The header looks like any other filter, but instead of pcrs jobs, external
+ filters contain a single job which can be a program or a shell script (which
+ may call other scripts or programs).
+</para>
+<para>
+ External filters read the content from STDIN and write the rewritten
+ content to STDOUT. The environment variables PRIVOXY_URL, PRIVOXY_PATH,
+ PRIVOXY_HOST, PRIVOXY_ORIGIN can be used to get some details about the
+ client request.
+</para>
+<para>
+ &my-app; will temporary store the content to filter in the
+ <literal><link linkend="temporary-directory">temporary-directory</link></literal>.
+</para>
+<para>
+ <screen>
+EXTERNAL-FILTER: cat Pointless example filter that doesn't actually modify the content
+/bin/cat
+
+# Incorrect reimplementation of the filter above in POSIX shell.
+#
+# Note that it's a single job that spans multiple lines, the line
+# breaks are not passed to the shell, thus the semicolons are required.
+#
+# If the script isn't trivial, it is recommended to put it into an external file.
+#
+# In general, writing external filters entirely in POSIX shell is not
+# considered a good idea.
+EXTERNAL-FILTER: cat2 Pointless example filter that despite its name may actually modify the content
+while read line; \
+do \
+ echo "$line"; \
+done
+
+EXTERNAL-FILTER: rotate-image Rotate an image by 180 degree. Test filter with limited value.
+/usr/local/bin/convert - -rotate 180 -
+
+EXTERNAL-FILTER: citation-needed Adds a "[citation needed]" tag to an image. The coordinates may need adjustment.
+/usr/local/bin/convert - -pointsize 16 -fill white -annotate +17+418 "[citation needed]" -
+</screen>
+</para>
+
+<warning>
+ <para>
+ Currently external filters are executed with &my-app;'s privileges!
+ Only use external filters you understand and trust.
+ </para>
+</warning>
+<para>
+ External filters are experimental and the syntax may change in the future.
+</para>
+</sect2>
+
</sect1>
<!-- ~ End section ~ -->
<!-- ~~~~~ New section ~~~~~ -->
-<sect2>
+<sect2 id="internal-pages">
<title>Privoxy's Internal Pages</title>
<para>
</itemizedlist>
</para>
-<para>
- These may be bookmarked for quick reference. See next.
-
-</para>
-
-<sect3 id="bookmarklets">
-<title>Bookmarklets</title>
-<para>
- Below are some <quote>bookmarklets</quote> to allow you to easily access a
- <quote>mini</quote> version of some of <application>Privoxy's</application>
- special pages. They are designed for MS Internet Explorer, but should work
- equally well in Netscape, Mozilla, and other browsers which support
- JavaScript. They are designed to run directly from your bookmarks - not by
- clicking the links below (although that should work for testing).
-</para>
-<para>
- To save them, right-click the link and choose <quote>Add to Favorites</quote>
- (IE) or <quote>Add Bookmark</quote> (Netscape). You will get a warning that
- the bookmark <quote>may not be safe</quote> - just click OK. Then you can run the
- Bookmarklet directly from your favorites/bookmarks. For even faster access,
- you can put them on the <quote>Links</quote> bar (IE) or the <quote>Personal
- Toolbar</quote> (Netscape), and run them with a single click.
-</para>
-
-<para>
- <itemizedlist>
-
- <listitem>
- <para>
- <ulink
- url="javascript:void(window.open('http://config.privoxy.org/toggle?mini=y&set=enabled','ijbstatus','width=250,height=100,resizable=yes,scrollbars=no,toolbar=no,location=no,directories=no,status=no,menubar=no,copyhistory=no').focus());">Privoxy - Enable</ulink>
- </para>
- </listitem>
-
- <listitem>
- <para>
- <ulink
- url="javascript:void(window.open('http://config.privoxy.org/toggle?mini=y&set=disabled','ijbstatus','width=250,height=100,resizable=yes,scrollbars=no,toolbar=no,location=no,directories=no,status=no,menubar=no,copyhistory=no').focus());">Privoxy - Disable</ulink>
- </para>
- </listitem>
-
- <listitem>
- <para>
- <ulink
- url="javascript:void(window.open('http://config.privoxy.org/toggle?mini=y&set=toggle','ijbstatus','width=250,height=100,resizable=yes,scrollbars=no,toolbar=no,location=no,directories=no,status=no,menubar=no,copyhistory=no').focus());">Privoxy - Toggle Privoxy</ulink> (Toggles between enabled and disabled)
- </para>
- </listitem>
-
- <listitem>
- <para>
- <ulink
- url="javascript:void(window.open('http://config.privoxy.org/toggle?mini=y','ijbstatus','width=250,height=2,resizable=yes,scrollbars=no,toolbar=no,location=no,directories=no,status=no,menubar=no,copyhistory=no').focus());">Privoxy- View Status</ulink>
- </para>
- </listitem>
-<!--
- <listitem>
- <para>
- <ulink url="javascript:w=Math.floor(screen.width/2);h=Math.floor(screen.height*0.9);void(window.open('http://www.privoxy.org/actions/index.php?url='+escape(location.href),'Feedback','screenx='+w+',width='+w+',height='+h+',scrollbars=yes,toolbar=no,location=no,directories=no,status=no,menubar=no,copyhistory=no').focus());">Privoxy - Submit Actions File Feedback</ulink>
- </para>
- </listitem>
- -->
- <listitem>
- <para>
- <ulink url="javascript:void(window.open('http://config.privoxy.org/show-url-info?url='+escape(location.href),'Why').focus());">Privoxy - Why?</ulink>
- </para>
- </listitem>
- </itemizedlist>
-</para>
-
-<para>
- Credit: The site which gave us the general idea for these bookmarklets is
- <ulink url="http://www.bookmarklets.com/">www.bookmarklets.com</ulink>. They
- have more information about bookmarklets.
-</para>
-
-
-</sect3>
-
</sect2>
<para>
One quick test to see if <application>Privoxy</application> is causing a problem
or not, is to disable it temporarily. This should be the first troubleshooting
- step. See <link linkend="bookmarklets">the Bookmarklets</link> section on a quick
- and easy way to do this (be sure to flush caches afterward!). Looking at the
+ step (be sure to flush caches afterward!). Looking at the
logs is a good idea too. (Note that both the toggle feature and logging are
enabled via <filename>config</filename> file settings, and may need to be
turned <quote>on</quote>.)
projects / privoxy.git / blobdiff