Purpose : Used with other docs and files only.
- $Id: p-config.sgml,v 2.121 2016/05/03 13:22:13 fabiankeil Exp $
+ $Id: p-config.sgml,v 2.127 2017/06/26 12:14:38 fabiankeil Exp $
- Copyright (C) 2001-2016 Privoxy Developers https://www.privoxy.org/
+ Copyright (C) 2001-2017 Privoxy Developers https://www.privoxy.org/
See LICENSE.
========================================================================
Sample Configuration File for Privoxy &p-version;
</title>
<para>
- $Id: p-config.sgml,v 2.121 2016/05/03 13:22:13 fabiankeil Exp $
+ $Id: p-config.sgml,v 2.127 2017/06/26 12:14:38 fabiankeil Exp $
</para>
<para>
-Copyright (C) 2001-2016 Privoxy Developers https://www.privoxy.org/
+Copyright (C) 2001-2017 Privoxy Developers https://www.privoxy.org/
</para>
<para>
<![%config-file;[<literallayout>@@enable-proxy-authentication-forwarding 0</literallayout>]]>
</sect3>
+<!-- ~~~~~ New section ~~~~~ -->
+<sect3 renderas="sect4" id="trusted-cgi-referer"><title>trusted-cgi-referer</title>
+<variablelist>
+ <varlistentry>
+ <term>Specifies:</term>
+ <listitem>
+ <para>
+ A trusted website or webpage whose links can be followed to reach sensitive CGI pages
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>Type of value:</term>
+ <listitem>
+ <para>URL or URL prefix</para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>Default value:</term>
+ <listitem>
+ <para>Unset</para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>Effect if unset:</term>
+ <listitem>
+ <para>
+ No external pages are considered trusted referers.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>Notes:</term>
+ <listitem>
+ <para>
+ Before &my-app; accepts configuration changes through CGI pages like
+ <link linkend="client-specific-tag">client-tags</link> or the
+ <link linkend="enable-remote-toggle">remote toggle</link>, it checks
+ the Referer header to see if the request comes from a trusted source.
+ </para>
+ <para>
+ By default only the webinterface domains
+ <ulink url="http://config.privoxy.org/">config.privoxy.org</ulink>
+ and
+ <ulink url="http://p.p/">p.p</ulink>
+ are considered trustworthy.
+ Requests originating from other domains are rejected to prevent
+ third-parties from modifiying Privoxy's state by e.g. embedding
+ images that result in CGI requests.
+ </para>
+ <para>
+ In some environments it may be desirable to embed links to CGI pages
+ on external pages, for example on an Intranet homepage the Privoxy admin
+ controls.
+ </para>
+ <para>
+ The <quote>trusted-cgi-referer</quote> option can be used to add that page,
+ or the whole domain, as trusted source so the resulting requests aren't
+ rejected.
+ Requests are accepted if the specified trusted-cgi-refer is the prefix
+ of the Referer.
+ </para>
+ <warning>
+ <para>
+ Declaring pages the admin doesn't control trustworthy may allow
+ malicious third parties to modify Privoxy's internal state against
+ the user's wishes and without the user's knowledge.
+ </para>
+ </warning>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<![%config-file;[<literallayout>@@trusted-cgi-referer http://www.example.org/local-privoxy-control-page</literallayout>]]>
+</sect3>
+
</sect2>
<!-- ~ End section ~ -->
</sect3>
+<sect3 renderas="sect4" id="listen-backlog"><title>listen-backlog</title>
+<variablelist>
+ <varlistentry>
+ <term>Specifies:</term>
+ <listitem>
+ <para>
+ Connection queue length requested from the operating system.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>Type of value:</term>
+ <listitem>
+ <para>
+ <replaceable>Number.</replaceable>
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>Default value:</term>
+ <listitem>
+ <para>128</para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>Effect if unset:</term>
+ <listitem>
+ <para>
+ A connection queue length of 128 is requested from the operating system.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>Notes:</term>
+ <listitem>
+ <para>
+ Under high load incoming connection may queue up before Privoxy
+ gets around to serve them. The queue length is limitted by the
+ operating system. Once the queue is full, additional connections
+ are dropped before Privoxy can accept and serve them.
+ </para>
+ <para>
+ Increasing the queue length allows Privoxy to accept more
+ incomming connections that arrive roughly at the same time.
+ </para>
+ <para>
+ Note that Privoxy can only request a certain queue length,
+ whether or not the requested length is actually used depends
+ on the operating system which may use a different length instead.
+ </para>
+ <para>
+ On many operating systems a limit of -1 can be specified to
+ instruct the operating system to use the maximum queue length
+ allowed. Check the listen man page to see if your platform allows this.
+ </para>
+ <para>
+ On some platforms you can use "netstat -Lan -p tcp" to see the effective
+ queue length.
+ </para>
+ <para>
+ Effectively using a value above 128 usually requires changing
+ the system configuration as well. On FreeBSD-based system the
+ limit is controlled by the kern.ipc.soacceptqueue sysctl.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>Examples:</term>
+ <listitem>
+ <para>
+ listen-backlog 4096
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+<![%config-file;[<literallayout>@@#listen-backlog -1</literallayout>]]>
+</sect3>
+
+
+<sect3 renderas="sect4" id="enable-accept-filter"><title>enable-accept-filter</title>
+<variablelist>
+ <varlistentry>
+ <term>Specifies:</term>
+ <listitem>
+ <para>
+ Whether or not Privoxy should use an accept filter
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>Type of value:</term>
+ <listitem>
+ <para>
+ <replaceable>0 or 1</replaceable>
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>Default value:</term>
+ <listitem>
+ <para>0</para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>Effect if unset:</term>
+ <listitem>
+ <para>
+ No accept filter is enabled.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>Notes:</term>
+ <listitem>
+ <para>
+ Accept filters reduce the number of context switches by not
+ passing sockets for new connections to Privoxy until a complete
+ HTTP request is available.
+ </para>
+ <para>
+ As a result, Privoxy can process the whole request right away
+ without having to wait for additional data first.
+ </para>
+ <para>
+ For this option to work, Privoxy has to be compiled with
+ FEATURE_ACCEPT_FILTER and the operating system has to support
+ it (which may require loading a kernel module).
+ </para>
+ <para>
+ Currently accept filters are only supported on FreeBSD-based
+ systems. Check the
+ <ulink url="https://www.freebsd.org/cgi/man.cgi?query=accf_http">accf_http(9)
+ man page</ulink>
+ to learn how to enable the support in the operating system.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>Examples:</term>
+ <listitem>
+ <para>
+ enable-accept-filter 1
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+<![%config-file;[<literallayout>@@#enable-accept-filter 1</literallayout>]]>
+</sect3>
+
+
<sect3 renderas="sect4" id="handle-as-empty-doc-returns-ok"><title>handle-as-empty-doc-returns-ok</title>
<variablelist>
<varlistentry>
</variablelist>
</sect3>
-</sect2>
+<!-- ~ End section ~ -->
+
+<sect3 renderas="sect4" id="trust-x-forwarded-for"><title>trust-x-forwarded-for</title>
+<variablelist>
+ <varlistentry>
+ <term>Specifies:</term>
+ <listitem>
+ <para>
+ Whether or not Privoxy should use IP addresses specified with the X-Forwarded-For header
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>Type of value:</term>
+ <listitem>
+ <para>
+ <replaceable>0 or one</replaceable>
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>Default value:</term>
+ <listitem>
+ <para>0</para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>Notes:</term>
+ <listitem>
+ <warning>
+ <para>
+ This is an experimental feature. The syntax is likely to change
+ in future versions.
+ </para>
+ </warning>
+ <para>
+ If clients reach Privoxy through another proxy, for example a load
+ balancer, Privoxy can't tell the client's IP address from the connection.
+ If multiple clients use the same proxy, they will share the same
+ client tag settings which is usually not desired.
+ </para>
+ <para>
+ This option lets Privoxy use the X-Forwarded-For header value as
+ client IP address. If the proxy sets the header, multiple clients
+ using the same proxy do not share the same client tag settings.
+ </para>
+ <para>
+ This option should only be enabled if Privoxy can only be reached
+ through a proxy and if the proxy can be trusted to set the header
+ correctly. It is recommended that ACL are used to make sure only
+ trusted systems can reach Privoxy.
+ </para>
+ <para>
+ If access to Privoxy isn't limited to trusted systems, this option
+ would allow malicious clients to change the client tags for other
+ clients or increase Privoxy's memory requirements by registering
+ lots of client tag settings for clients that don't exist.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>Examples:</term>
+ <listitem>
+ <para>
+ <screen>
+ # Allow systems that can reach Privoxy to provide the client
+ # IP address with a X-Forwarded-For header.
+ trust-x-forwarded-for 1
+ </screen>
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</sect3>
<!-- ~ End section ~ -->
+<!-- ~~~~~ New section ~~~~~ -->
+
+<sect3 renderas="sect4" id="receive-buffer-size"><title>receive-buffer-size</title>
+<variablelist>
+ <varlistentry>
+ <term>Specifies:</term>
+ <listitem>
+ <para>
+ The size of the buffer Privoxy uses to receive data from the server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>Type of value:</term>
+ <listitem>
+ <para>
+ <replaceable>Size in bytes</replaceable>
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>Default value:</term>
+ <listitem>
+ <para>5000</para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>Notes:</term>
+ <listitem>
+ <para>
+ Increasing the receive-buffer-size increases Privoxy's memory usage but
+ can lower the number of context switches and thereby reduce the
+ cpu usage and potentially increase the throughput.
+ </para>
+ <para>
+ This is mostly relevant for fast network connections and
+ large downloads that don't require filtering.
+ </para>
+ <para>
+ Reducing the buffer size reduces the amount of memory Privoxy
+ needs to handle the request but increases the number of systemcalls
+ and may reduce the throughput.
+ </para>
+ <para>
+ A dtrace command like:
+ <quote>sudo dtrace -n 'syscall::read:return /execname == "privoxy"/ { @[execname] = llquantize(arg0, 10, 0, 5, 20); @m = max(arg0)}'</quote>
+ can be used to properly tune the receive-buffer-size.
+ On systems without dtrace, strace or truss may be used as
+ less convenient alternatives.
+ </para>
+ <para>
+ If the buffer is too large it will increase Privoxy's memory
+ footprint without any benefit. As the memory is (currently)
+ cleared before using it, a buffer that is too large can
+ actually reduce the throughput.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>Examples:</term>
+ <listitem>
+ <para>
+ <screen>
+ # Increase the receive buffer size
+ receive-buffer-size 32768
+ </screen>
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</sect3>
+
+<!-- ~ End section ~ -->
+
+</sect2>
<!-- ~~~~~ New section ~~~~~ -->
projects / privoxy.git / blobdiff