X-Git-Url: http://www.privoxy.org/gitweb/?p=privoxy.git;a=blobdiff_plain;f=doc%2Fwebserver%2Fuser-manual%2Fconfig.html;h=5cad65b767b7b00502457d2d1143b20a64bd0b2f;hp=5675b745ef8097297e1c889781e051395f0e22cf;hb=42c361793c45b0d5fc0c116707ca12b2f60f4c52;hpb=2da7c5e4fb2bd663ff7118bbabd2f0f4b3ea98dc diff --git a/doc/webserver/user-manual/config.html b/doc/webserver/user-manual/config.html index 5675b745..5cad65b7 100644 --- a/doc/webserver/user-manual/config.html +++ b/doc/webserver/user-manual/config.html @@ -1,4612 +1,4282 @@ - -The Main Configuration File - -
Privoxy 3.0.13 User Manual
PrevNext

7. The Main Configuration File

Again, the main configuration file is named config on - Linux/Unix/BSD and OS/2, and config.txt on Windows. - Configuration lines consist of an initial keyword followed by a list of - values, all separated by whitespace (any number of spaces or tabs). For - example:

  confdir /etc/privoxy

-

Assigns the value /etc/privoxy to the option - confdir and thus indicates that the configuration - directory is named "/etc/privoxy/".

All options in the config file except for confdir and - logdir are optional. Watch out in the below description - for what happens if you leave them unset.

The main config file controls all aspects of Privoxy's - operation that are not location dependent (i.e. they apply universally, no matter - where you may be surfing). Like the filter and action files, the config file is - a plain text file and can be modified with a text editor like emacs, vim or - notepad.exe.

7.1. Local Set-up Documentation

If you intend to operate Privoxy for more users - than just yourself, it might be a good idea to let them know how to reach - you, what you block and why you do that, your policies, etc. -

7.1.1. user-manual

Specifies:

Location of the Privoxy User Manual. -

Type of value:

A fully qualified URI

Default value:

Unset

Effect if unset:

http://www.privoxy.org/version/user-manual/ - will be used, where version is the Privoxy version. -

Notes:

The User Manual URI is the single best source of information on - Privoxy, and is used for help links from some - of the internal CGI pages. The manual itself is normally packaged with the - binary distributions, so you probably want to set this to a locally - installed copy. -

Examples: -

The best all purpose solution is simply to put the full local - PATH to where the User Manual is - located: -

  user-manual  /usr/share/doc/privoxy/user-manual
-

The User Manual is then available to anyone with access to - Privoxy, by following the built-in URL: - http://config.privoxy.org/user-manual/ - (or the shortcut: http://p.p/user-manual/). -

If the documentation is not on the local system, it can be accessed - from a remote server, as: -

  user-manual  http://example.com/privoxy/user-manual/
-

Warning

If set, this option should be the first option in the config - file, because it is used while the config file is being read - on start-up. -

7.1.2. trust-info-url

Specifies:

A URL to be displayed in the error page that users will see if access to an untrusted page is denied. -

Type of value:

URL

Default value:

Unset

Effect if unset:

No links are displayed on the "untrusted" error page. -

Notes:

The value of this option only matters if the experimental trust mechanism has been - activated. (See trustfile below.) -

If you use the trust mechanism, it is a good idea to write up some on-line - documentation about your trust policy and to specify the URL(s) here. - Use multiple times for multiple URLs. -

The URL(s) should be added to the trustfile as well, so users don't end up - locked out from the information on why they were locked out in the first place! -

7.1.3. admin-address

Specifies:

An email address to reach the Privoxy administrator. -

Type of value:

Email address

Default value:

Unset

Effect if unset:

No email address is displayed on error pages and the CGI user interface. -

Notes:

If both admin-address and proxy-info-url - are unset, the whole "Local Privoxy Support" box on all generated pages will - not be shown. -

7.1.4. proxy-info-url

Specifies:

A URL to documentation about the local Privoxy setup, - configuration or policies. -

Type of value:

URL

Default value:

Unset

Effect if unset:

No link to local documentation is displayed on error pages and the CGI user interface. -

Notes:

If both admin-address and proxy-info-url - are unset, the whole "Local Privoxy Support" box on all generated pages will - not be shown. -

This URL shouldn't be blocked ;-) -

7.2. Configuration and Log File Locations

Privoxy can (and normally does) use a number of - other files for additional configuration, help and logging. - This section of the configuration file tells Privoxy - where to find those other files.

The user running Privoxy, must have read - permission for all configuration files, and write permission to any files - that would be modified, such as log files and actions files.

7.2.1. confdir

Specifies:

The directory where the other configuration files are located.

Type of value:

Path name

Default value:

/etc/privoxy (Unix) or Privoxy installation dir (Windows)

Effect if unset:

Mandatory

Notes:

No trailing "/", please. -

7.2.2. templdir

Specifies:

An alternative directory where the templates are loaded from.

Type of value:

Path name

Default value:

unset

Effect if unset:

The templates are assumed to be located in confdir/template.

Notes:

Privoxy's original templates are usually - overwritten with each update. Use this option to relocate customized - templates that should be kept. As template variables might change - between updates, you shouldn't expect templates to work with - Privoxy releases other than the one - they were part of, though. -

7.2.3. logdir

Specifies:

The directory where all logging takes place - (i.e. where the logfile is located). -

Type of value:

Path name

Default value:

/var/log/privoxy (Unix) or Privoxy installation dir (Windows)

Effect if unset:

Mandatory

Notes:

No trailing "/", please. -

7.2.4. actionsfile

Specifies:

The actions file(s) to use -

Type of value:

Complete file name, relative to confdir

Default values:

  match-all.action # Actions that are applied to all sites and maybe overruled later on.

-

  default.action   # Main actions file

-

  user.action      # User customizations

-

Effect if unset:

No actions are taken at all. More or less neutral proxying. -

Notes:

Multiple actionsfile lines are permitted, and are in fact recommended! -

- The default values are default.action, which is the - "main" actions file maintained by the developers, and - user.action, where you can make your personal additions. -

- Actions files contain all the per site and per URL configuration for - ad blocking, cookie management, privacy considerations, etc. - There is no point in using Privoxy without at - least one actions file. -

Note that since Privoxy 3.0.7, the complete filename, including the ".action" - extension has to be specified. The syntax change was necessary to be consistent - with the other file options and to allow previously forbidden characters. -

7.2.5. filterfile

Specifies:

The filter file(s) to use -

Type of value:

File name, relative to confdir

Default value:

default.filter (Unix) or default.filter.txt (Windows)

Effect if unset:

No textual content filtering takes place, i.e. all - +filter{name} - actions in the actions files are turned neutral. -

Notes:

Multiple filterfile lines are permitted. -

The filter files contain content modification - rules that use regular expressions. These rules permit - powerful changes on the content of Web pages, and optionally the headers - as well, e.g., you could try to disable your favorite JavaScript annoyances, - re-write the actual displayed text, or just have some fun - playing buzzword bingo with web pages. -

The - +filter{name} - actions rely on the relevant filter (name) - to be defined in a filter file! -

A pre-defined filter file called default.filter that contains - a number of useful filters for common problems is included in the distribution. - See the section on the filter - action for a list. -

It is recommended to place any locally adapted filters into a separate - file, such as user.filter. -

7.2.6. logfile

Specifies:

The log file to use -

Type of value:

File name, relative to logdir

Default value:

Unset (commented out). When activated: logfile (Unix) or privoxy.log (Windows).

Effect if unset:

No logfile is written. -

Notes:

The logfile is where all logging and error messages are written. The level - of detail and number of messages are set with the debug - option (see below). The logfile can be useful for tracking down a problem with - Privoxy (e.g., it's not blocking an ad you - think it should block) and it can help you to monitor what your browser - is doing. -

Depending on the debug options below, the logfile may be a privacy risk - if third parties can get access to it. As most users will never look - at it, Privoxy 3.0.7 and later only log fatal - errors by default. -

For most troubleshooting purposes, you will have to change that, - please refer to the debugging section for details. -

Your logfile will grow indefinitely, and you will probably want to - periodically remove it. On Unix systems, you can do this with a cron job - (see "man cron"). For Red Hat based Linux distributions, a - logrotate script has been included. -

Any log files must be writable by whatever user Privoxy - is being run as (on Unix, default user id is "privoxy"). -

7.2.7. trustfile

Specifies:

The name of the trust file to use -

Type of value:

File name, relative to confdir

Default value:

Unset (commented out). When activated: trust (Unix) or trust.txt (Windows)

Effect if unset:

The entire trust mechanism is disabled. -

Notes:

The trust mechanism is an experimental feature for building white-lists and should - be used with care. It is NOT recommended for the casual user. -

If you specify a trust file, Privoxy will only allow - access to sites that are specified in the trustfile. Sites can be listed - in one of two ways: -

Prepending a ~ character limits access to this site - only (and any sub-paths within this site), e.g. - ~www.example.com allows access to - ~www.example.com/features/news.html, etc. -

Or, you can designate sites as trusted referrers, by - prepending the name with a + character. The effect is that - access to untrusted sites will be granted -- but only if a link from this - trusted referrer was used to get there. The link target will then be added - to the "trustfile" so that future, direct accesses will be - granted. Sites added via this mechanism do not become trusted referrers - themselves (i.e. they are added with a ~ designation). - There is a limit of 512 such entries, after which new entries will not be - made. -

If you use the + operator in the trust file, it may grow - considerably over time. -

It is recommended that Privoxy be compiled with - the --disable-force, --disable-toggle and - --disable-editor options, if this feature is to be - used. -

Possible applications include limiting Internet access for children. -

7.3. Debugging

These options are mainly useful when tracing a problem. - Note that you might also want to invoke - Privoxy with the --no-daemon - command line option when debugging. -

7.3.1. debug

Specifies:

Key values that determine what information gets logged. -

Type of value:

Integer values

Default value:

0 (i.e.: only fatal errors (that cause Privoxy to exit) are logged)

Effect if unset:

Default value is used (see above). -

Notes:

The available debug levels are: -

+ +
  debug     1 # Log the destination for each request Privoxy let through. See also debug 1024.
+
+
+  
+    
+      The Main Configuration File
+    
+    
+    
+    
+    
+    
+    
+    
+  
+  
+    
+    
+

+ 7. The Main Configuration File +

+

+ By default, the main configuration file is named config, with the exception of Windows, where it is + named config.txt. Configuration lines + consist of an initial keyword followed by a list of values, all + separated by whitespace (any number of spaces or tabs). For example: +

+

+

+

+   confdir /etc/privoxy +

+ +

+ Assigns the value /etc/privoxy to the option + confdir and thus indicates that the + configuration directory is named "/etc/privoxy/". +

+

+ All options in the config file except for confdir and logdir are + optional. Watch out in the below description for what happens if you + leave them unset. +

+

+ The main config file controls all aspects of Privoxy's operation that are not location + dependent (i.e. they apply universally, no matter where you may be + surfing). Like the filter and action files, the config file is a + plain text file and can be modified with a text editor like emacs, + vim or notepad.exe. +

+
+

+ 7.1. Local Set-up Documentation +

+

+ If you intend to operate Privoxy + for more users than just yourself, it might be a good idea to let + them know how to reach you, what you block and why you do that, + your policies, etc. +

+
+

+ 7.1.1. user-manual +

+
+
+
+ Specifies: +
+
+

+ Location of the Privoxy + User Manual. +

+
+
+ Type of value: +
+
+

+ A fully qualified URI +

+
+
+ Default value: +
+
+

+ Unset +

+
+
+ Effect if unset: +
+
+

+ https://www.privoxy.org/version/user-manual/ will be + used, where version is + the Privoxy version. +

+
+
+ Notes: +
+
+

+ The User Manual URI is the single best source of + information on Privoxy, + and is used for help links from some of the internal CGI + pages. The manual itself is normally packaged with the + binary distributions, so you probably want to set this to a + locally installed copy. +

+

+ Examples: +

+

+ The best all purpose solution is simply to put the full + local PATH to where the User Manual is located: +

+

+

+ + + + +
+
+  user-manual  /usr/share/doc/privoxy/user-manual
+
+
+ +

+ The User Manual is then available to anyone with access to + Privoxy, by following the + built-in URL: http://config.privoxy.org/user-manual/ (or + the shortcut: http://p.p/user-manual/). +

+

+ If the documentation is not on the local system, it can be + accessed from a remote server, as: +

+

+

+ + + + +
+
+  user-manual  http://example.com/privoxy/user-manual/
+
+
+ +
+ + + + + + + +
+ Warning +
+

+ If set, this option should be the first option in + the config file, because it is used + while the config file is being read on start-up. +

+
+
+
+
+
+
+
+

+ 7.1.2. trust-info-url +

+
+
+
+ Specifies: +
+
+

+ A URL to be displayed in the error page that users will see + if access to an untrusted page is denied. +

+
+
+ Type of value: +
+
+

+ URL +

+
+
+ Default value: +
+
+

+ Unset +

+
+
+ Effect if unset: +
+
+

+ No links are displayed on the "untrusted" error page. +

+
+
+ Notes: +
+
+

+ The value of this option only matters if the experimental + trust mechanism has been activated. (See trustfile below.) +

+

+ If you use the trust mechanism, it is a good idea to write + up some on-line documentation about your trust policy and + to specify the URL(s) here. Use multiple times for multiple + URLs. +

+

+ The URL(s) should be added to the trustfile as well, so + users don't end up locked out from the information on why + they were locked out in the first place! +

+
+
+
+
+
+

+ 7.1.3. admin-address +

+
+
+
+ Specifies: +
+
+

+ An email address to reach the Privoxy administrator. +

+
+
+ Type of value: +
+
+

+ Email address +

+
+
+ Default value: +
+
+

+ Unset +

+
+
+ Effect if unset: +
+
+

+ No email address is displayed on error pages and the CGI + user interface. +

+
+
+ Notes: +
+
+

+ If both admin-address and proxy-info-url are unset, the whole + "Local Privoxy Support" box on all generated pages will not + be shown. +

+
+
+
+
+
+

+ 7.1.4. proxy-info-url +

+
+
+
+ Specifies: +
+
+

+ A URL to documentation about the local Privoxy setup, configuration or + policies. +

+
+
+ Type of value: +
+
+

+ URL +

+
+
+ Default value: +
+
+

+ Unset +

+
+
+ Effect if unset: +
+
+

+ No link to local documentation is displayed on error pages + and the CGI user interface. +

+
+
+ Notes: +
+
+

+ If both admin-address and proxy-info-url are unset, the whole + "Local Privoxy Support" box on all generated pages will not + be shown. +

+

+ This URL shouldn't be blocked ;-) +

+
+
+
+
+
+
+

+ 7.2. Configuration and Log File + Locations +

+

+ Privoxy can (and normally does) + use a number of other files for additional configuration, help and + logging. This section of the configuration file tells Privoxy where to find those other files. +

+

+ The user running Privoxy, must + have read permission for all configuration files, and write + permission to any files that would be modified, such as log files + and actions files. +

+
+

+ 7.2.1. confdir +

+
+
+
+ Specifies: +
+
+

+ The directory where the other configuration files are + located. +

+
+
+ Type of value: +
+
+

+ Path name +

+
+
+ Default value: +
+
+

+ /etc/privoxy (Unix) or Privoxy installation dir (Windows) +

+
+
+ Effect if unset: +
+
+

+ Mandatory +

+
+
+ Notes: +
+
+

+ No trailing "/", please. +

+
+
+
+
+
+

+ 7.2.2. templdir +

+
+
+
+ Specifies: +
+
+

+ An alternative directory where the templates are loaded + from. +

+
+
+ Type of value: +
+
+

+ Path name +

+
+
+ Default value: +
+
+

+ unset +

+
+
+ Effect if unset: +
+
+

+ The templates are assumed to be located in + confdir/template. +

+
+
+ Notes: +
+
+

+ Privoxy's original + templates are usually overwritten with each update. Use + this option to relocate customized templates that should be + kept. As template variables might change between updates, + you shouldn't expect templates to work with Privoxy releases other than the one + they were part of, though. +

+
+
+
+
+
+

+ 7.2.3. temporary-directory +

+
+
+
+ Specifies: +
+
+

+ A directory where Privoxy can create temporary files. +

+
+
+ Type of value: +
+
+

+ Path name +

+
+
+ Default value: +
+
+

+ unset +

+
+
+ Effect if unset: +
+
+

+ No temporary files are created, external filters don't + work. +

+
+
+ Notes: +
+
+

+ To execute external + filters, Privoxy + has to create temporary files. This directive specifies the + directory the temporary files should be written to. +

+

+ It should be a directory only Privoxy (and trusted users) can + access. +

+
+
+
+
+
+

+ 7.2.4. logdir +

+
+
+
+ Specifies: +
+
+

+ The directory where all logging takes place (i.e. where the + logfile is located). +

+
+
+ Type of value: +
+
+

+ Path name +

+
+
+ Default value: +
+
+

+ /var/log/privoxy (Unix) or Privoxy installation dir (Windows) +

+
+
+ Effect if unset: +
+
+

+ Mandatory +

+
+
+ Notes: +
+
+

+ No trailing "/", please. +

+
+
+
+
+
+

+ 7.2.5. actionsfile +

+ +
+
+
+ Specifies: +
+
+

+ The actions file(s) to use +

+
+
+ Type of value: +
+
+

+ Complete file name, relative to confdir +

+
+
+ Default values: +
+
+ + + + + + + + + + + + +
+

+   match-all.action # Actions that are applied to all sites and maybe overruled later on. +

+
+

+   default.action   # Main actions file +

+
+

+   user.action      # User customizations +

+
+
+
+ Effect if unset: +
+
+

+ No actions are taken at all. More or less neutral proxying. +

+
+
+ Notes: +
+
+

+ Multiple actionsfile lines are + permitted, and are in fact recommended! +

+

+ The default values are default.action, which is the "main" actions file maintained by the + developers, and user.action, + where you can make your personal additions. +

+

+ Actions files contain all the per site and per URL + configuration for ad blocking, cookie management, privacy + considerations, etc. +

+
+
+
+
+
+

+ 7.2.6. filterfile +

+ +
+
+
+ Specifies: +
+
+

+ The filter file(s) to use +

+
+
+ Type of value: +
+
+

+ File name, relative to confdir +

+
+
+ Default value: +
+
+

+ default.filter (Unix) or default.filter.txt (Windows) +

+
+
+ Effect if unset: +
+
+

+ No textual content filtering takes place, i.e. all +filter{name} actions in the actions + files are turned neutral. +

+
+
+ Notes: +
+
+

+ Multiple filterfile lines are + permitted. +

+

+ The filter files contain + content modification rules that use regular expressions. These rules + permit powerful changes on the content of Web pages, and + optionally the headers as well, e.g., you could try to + disable your favorite JavaScript annoyances, re-write the + actual displayed text, or just have some fun playing + buzzword bingo with web pages. +

+

+ The +filter{name} actions rely on the + relevant filter (name) + to be defined in a filter file! +

+

+ A pre-defined filter file called default.filter that contains a number of + useful filters for common problems is included in the + distribution. See the section on the filter action for + a list. +

+

+ It is recommended to place any locally adapted filters into + a separate file, such as user.filter. +

+
+
+
+
+
+

+ 7.2.7. logfile +

+
+
+
+ Specifies: +
+
+

+ The log file to use +

+
+
+ Type of value: +
+
+

+ File name, relative to logdir +

+
+
+ Default value: +
+
+

+ Unset (commented + out). When activated: logfile (Unix) or + privoxy.log (Windows). +

+
+
+ Effect if unset: +
+
+

+ No logfile is written. +

+
+
+ Notes: +
+
+

+ The logfile is where all logging and error messages are + written. The level of detail and number of messages are set + with the debug option (see below). + The logfile can be useful for tracking down a problem with + Privoxy (e.g., it's not + blocking an ad you think it should block) and it can help + you to monitor what your browser is doing. +

+

+ Depending on the debug options below, the logfile may be a + privacy risk if third parties can get access to it. As most + users will never look at it, Privoxy only logs fatal errors by + default. +

+

+ For most troubleshooting purposes, you will have to change + that, please refer to the debugging section for details. +

+

+ Any log files must be writable by whatever user Privoxy is being run as (on + Unix, default user id is "privoxy"). +

+

+ To prevent the logfile from growing indefinitely, it is + recommended to periodically rotate or shorten it. Many + operating systems support log rotation out of the box, some + require additional software to do it. For details, please + refer to the documentation for your operating system. +

+
+
+
+
+
+

+ 7.2.8. trustfile +

+
+
+
+ Specifies: +
+
+

+ The name of the trust file to use +

+
+
+ Type of value: +
+
+

+ File name, relative to confdir +

+
+
+ Default value: +
+
+

+ Unset (commented + out). When activated: trust (Unix) or trust.txt + (Windows) +

+
+
+ Effect if unset: +
+
+

+ The entire trust mechanism is disabled. +

+
+
+ Notes: +
+
+

+ The trust mechanism is an experimental feature for building + white-lists and should be used with care. It is NOT + recommended for the casual user. +

+

+ If you specify a trust file, Privoxy will only allow access to + sites that are specified in the trustfile. Sites can be + listed in one of two ways: +

+

+ Prepending a ~ character limits + access to this site only (and any sub-paths within this + site), e.g. ~www.example.com + allows access to ~www.example.com/features/news.html, etc. +

+

+ Or, you can designate sites as trusted referrers, by + prepending the name with a + + character. The effect is that access to untrusted sites + will be granted -- but only if a link from this trusted + referrer was used to get there. The link target will then + be added to the "trustfile" so + that future, direct accesses will be granted. Sites added + via this mechanism do not become trusted referrers + themselves (i.e. they are added with a ~ designation). There is a limit of 512 such + entries, after which new entries will not be made. +

+

+ If you use the + operator in the + trust file, it may grow considerably over time. +

+

+ It is recommended that Privoxy be compiled with the --disable-force, --disable-toggle and --disable-editor options, if this feature is + to be used. +

+

+ Possible applications include limiting Internet access for + children. +

+
+
+
+
+
+
+

+ 7.3. Debugging +

+

+ These options are mainly useful when tracing a problem. Note that + you might also want to invoke Privoxy with the --no-daemon command line option when debugging. +

+
+

+ 7.3.1. debug +

+
+
+
+ Specifies: +
+
+

+ Key values that determine what information gets logged. +

+
+
+ Type of value: +
+
+

+ Integer values +

+
+
+ Default value: +
+
+

+ 0 (i.e.: only fatal errors (that cause Privoxy to exit) are + logged) +

+
+
+ Effect if unset: +
+
+

+ Default value is used (see above). +

+
+
+ Notes: +
+
+

+ The available debug levels are: +

+

+

+ + +
+
+  debug     1 # Log the destination for each request Privoxy let through. See also debug 1024.
   debug     2 # show each connection status
   debug     4 # show I/O status
   debug     8 # show header parsing
-  debug    16 # log all data written to the network into the logfile
+  debug    16 # log all data written to the network
   debug    32 # debug force feature
   debug    64 # debug regular expression filters
   debug   128 # debug redirects
   debug   256 # debug GIF de-animation
   debug   512 # Common Log Format
-  debug  1024 # Log the destination for requests Privoxy didn't let through, and the reason why.
+  debug  1024 # Log the destination for requests Privoxy didn't let through, and the reason why.
   debug  2048 # CGI user interface
   debug  4096 # Startup banner and warnings.
-  debug  8192 # Non-fatal errors
-

To select multiple debug levels, you can either add them or use - multiple debug lines. -

A debug level of 1 is informative because it will show you each request - as it happens. 1, 1024, 4096 and 8192 are recommended - so that you will notice when things go wrong. The other levels are - probably only of interest if you are hunting down a specific problem. - They can produce a hell of an output (especially 16). - -

Privoxy used to ship with the debug levels recommended above enabled by - default, but due to privacy concerns 3.0.7 and later are configured to - only log fatal errors. -

If you are used to the more verbose settings, simply enable the debug lines - below again. -

If you want to use pure CLF (Common Log Format), you should set "debug - 512" ONLY and not enable anything else. -

Privoxy has a hard-coded limit for the - length of log messages. If it's reached, messages are logged truncated - and marked with "... [too long, truncated]". -

Please don't file any support requests without trying to reproduce - the problem with increased debug level first. Once you read the log - messages, you may even be able to solve the problem on your own. -

7.3.2. single-threaded

Specifies:

Whether to run only one server thread. -

Type of value:

None

Default value:

Unset

Effect if unset:

Multi-threaded (or, where unavailable: forked) operation, i.e. the ability to - serve multiple requests simultaneously. -

Notes:

This option is only there for debugging purposes. - It will drastically reduce performance. -

7.3.3. hostname

Specifies:

The hostname shown on the CGI pages. -

Type of value:

Text

Default value:

Unset

Effect if unset:

The hostname provided by the operating system is used. -

Notes:

On some misconfigured systems resolving the hostname fails or - takes too much time and slows Privoxy down. Setting a fixed hostname - works around the problem. -

In other circumstances it might be desirable to show a hostname - other than the one returned by the operating system. For example - if the system has several different hostnames and you don't want - to use the first one. -

Note that Privoxy does not validate the specified hostname value. -

7.4. Access Control and Security

This section of the config file controls the security-relevant aspects - of Privoxy's configuration. -

7.4.1. listen-address

Specifies:

The IP address and TCP port on which Privoxy will - listen for client requests. -

Type of value:

[IP-Address]:Port

Default value:

127.0.0.1:8118

Effect if unset:

Bind to 127.0.0.1 (IPv4 localhost), port 8118. This is suitable and - recommended for home users who run Privoxy on - the same machine as their browser. -

Notes:

You will need to configure your browser(s) to this proxy address and port. -

If you already have another service running on port 8118, or if you want to - serve requests from other machines (e.g. on your local network) as well, you - will need to override the default. -

IPv6 addresses containing colons have to be quoted by brackets. -

If you leave out the IP address, Privoxy will - bind to all IPv4 interfaces (addresses) on your machine and may become reachable - from the Internet. In that case, consider using access control lists (ACL's, see below), and/or - a firewall. If the hostname is localhost, Privoxy - will explicitly try to bind to an IPv4 address. For other hostnames it depends - on the operating system which IP version will be used. -

If you open Privoxy to untrusted users, you will - also want to make sure that the following actions are disabled: enable-edit-actions and - enable-remote-toggle -

Example:

Suppose you are running Privoxy on - a machine which has the address 192.168.0.1 on your local private network - (192.168.0.0) and has another outside connection with a different address. - You want it to serve requests from inside only: -

  listen-address  192.168.0.1:8118
-

Suppose you are running Privoxy on an - IPv6-capable machine and you want it to listen on the IPv6 address - of the loopback device: -

  listen-address [::1]:8118
-

7.4.2. toggle

Specifies:

Initial state of "toggle" status -

Type of value:

1 or 0

Default value:

1

Effect if unset:

Act as if toggled on -

Notes:

If set to 0, Privoxy will start in - "toggled off" mode, i.e. mostly behave like a normal, - content-neutral proxy with both ad blocking and content filtering - disabled. See enable-remote-toggle below. -

The windows version will only display the toggle icon in the system tray - if this option is present. -

7.4.3. enable-remote-toggle

Specifies:

Whether or not the web-based toggle - feature may be used -

Type of value:

0 or 1

Default value:

0

Effect if unset:

The web-based toggle feature is disabled. -

Notes:

When toggled off, Privoxy mostly acts like a normal, - content-neutral proxy, i.e. doesn't block ads or filter content. -

Access to the toggle feature can not be - controlled separately by "ACLs" or HTTP authentication, - so that everybody who can access Privoxy (see - "ACLs" and listen-address above) can - toggle it for all users. So this option is not recommended - for multi-user environments with untrusted users. -

Note that malicious client side code (e.g Java) is also - capable of using this option. -

As a lot of Privoxy users don't read - documentation, this feature is disabled by default. -

Note that you must have compiled Privoxy with - support for this feature, otherwise this option has no effect. -

7.4.4. enable-remote-http-toggle

Specifies:

Whether or not Privoxy recognizes special HTTP headers to change its behaviour. -

Type of value:

0 or 1

Default value:

0

Effect if unset:

Privoxy ignores special HTTP headers. -

Notes:

When toggled on, the client can change Privoxy's - behaviour by setting special HTTP headers. Currently the only supported - special header is "X-Filter: No", to disable filtering for - the ongoing request, even if it is enabled in one of the action files. -

This feature is disabled by default. If you are using - Privoxy in a environment with trusted clients, - you may enable this feature at your discretion. Note that malicious client - side code (e.g Java) is also capable of using this feature. -

This option will be removed in future releases as it has been obsoleted - by the more general header taggers. -

7.4.5. enable-edit-actions

Specifies:

Whether or not the web-based actions - file editor may be used -

Type of value:

0 or 1

Default value:

0

Effect if unset:

The web-based actions file editor is disabled. -

Notes:

Access to the editor can not be - controlled separately by "ACLs" or HTTP authentication, - so that everybody who can access Privoxy (see - "ACLs" and listen-address above) can - modify its configuration for all users. -

This option is not recommended for environments - with untrusted users and as a lot of Privoxy - users don't read documentation, this feature is disabled by default. -

Note that malicious client side code (e.g Java) is also - capable of using the actions editor and you shouldn't enable - this options unless you understand the consequences and are - sure your browser is configured correctly. -

Note that you must have compiled Privoxy with - support for this feature, otherwise this option has no effect. -

7.4.6. enforce-blocks

Specifies:

Whether the user is allowed to ignore blocks and can "go there anyway". -

Type of value:

0 or 1 -

Default value:

0

Effect if unset:

Blocks are not enforced. -

Notes:

Privoxy is mainly used to block and filter - requests as a service to the user, for example to block ads and other - junk that clogs the pipes. Privoxy's configuration - isn't perfect and sometimes innocent pages are blocked. In this situation it - makes sense to allow the user to enforce the request and have - Privoxy ignore the block. -

In the default configuration Privoxy's - "Blocked" page contains a "go there anyway" - link to adds a special string (the force prefix) to the request URL. - If that link is used, Privoxy will - detect the force prefix, remove it again and let the request pass. -

Of course Privoxy can also be used to enforce - a network policy. In that case the user obviously should not be able to - bypass any blocks, and that's what the "enforce-blocks" - option is for. If it's enabled, Privoxy hides - the "go there anyway" link. If the user adds the force - prefix by hand, it will not be accepted and the circumvention attempt - is logged. -

Examples:

enforce-blocks 1 -

7.4.7. ACLs: permit-access and deny-access

Specifies:

Who can access what. -

Type of value:

src_addr[:port][/src_masklen] - [dst_addr[:port][/dst_masklen]] -

Where src_addr and - dst_addr are IPv4 addresses in dotted decimal notation or valid - DNS names, port is a port - number, and src_masklen and - dst_masklen are subnet masks in CIDR notation, i.e. integer - values from 2 to 30 representing the length (in bits) of the network address. The masks and the whole - destination part are optional. -

If your system implements - RFC 3493, then - src_addr and dst_addr can be IPv6 addresses delimeted by - brackets, port can be a number - or a service name, and - src_masklen and - dst_masklen can be a number - from 0 to 128. -

Default value:

Unset

If no port is specified, - any port will match. If no src_masklen or - src_masklen is given, the complete IP - address has to match (i.e. 32 bits for IPv4 and 128 bits for IPv6). -

Effect if unset:

Don't restrict access further than implied by listen-address -

Notes:

Access controls are included at the request of ISPs and systems - administrators, and are not usually needed by individual users. - For a typical home user, it will normally suffice to ensure that - Privoxy only listens on the localhost - (127.0.0.1) or internal (home) network address by means of the - listen-address - option. -

Please see the warnings in the FAQ that Privoxy - is not intended to be a substitute for a firewall or to encourage anyone - to defer addressing basic security weaknesses. -

Multiple ACL lines are OK. - If any ACLs are specified, Privoxy only talks - to IP addresses that match at least one permit-access line - and don't match any subsequent deny-access line. In other words, the - last match wins, with the default being deny-access. -

If Privoxy is using a forwarder (see forward below) - for a particular destination URL, the dst_addr - that is examined is the address of the forwarder and NOT the address - of the ultimate target. This is necessary because it may be impossible for the local - Privoxy to determine the IP address of the - ultimate target (that's often what gateways are used for). -

You should prefer using IP addresses over DNS names, because the address lookups take - time. All DNS names must resolve! You can not use domain patterns - like "*.org" or partial domain names. If a DNS name resolves to multiple - IP addresses, only the first one is used. -

Some systems allows IPv4 client to connect to IPv6 server socket. - Then the client's IPv4 address will be translated by system into - IPv6 address space with special prefix ::ffff:0:0/96 (so called IPv4 - mapped IPv6 address). Privoxy can handle it - and maps such ACL addresses automatically. -

Denying access to particular sites by ACL may have undesired side effects - if the site in question is hosted on a machine which also hosts other sites - (most sites are). -

Examples:

Explicitly define the default behavior if no ACL and - listen-address are set: "localhost" - is OK. The absence of a dst_addr implies that - all destination addresses are OK: -

  permit-access  localhost
-

Allow any host on the same class C subnet as www.privoxy.org access to - nothing but www.example.com (or other domains hosted on the same system): -

  permit-access  www.privoxy.org/24 www.example.com/32
-

Allow access from any host on the 26-bit subnet 192.168.45.64 to anywhere, - with the exception that 192.168.45.73 may not access the IP address behind - www.dirty-stuff.example.com: -

  permit-access  192.168.45.64/26
-  deny-access    192.168.45.73    www.dirty-stuff.example.com
-

Allow access from the IPv4 network 192.0.2.0/24 even if listening on - an IPv6 wild card address (not supported on all platforms): -

  permit-access  192.0.2.0/24
-

This is equivalent to the following line even if listening on an - IPv4 address (not supported on all platforms): -

  permit-access  [::ffff:192.0.2.0]/120
-

7.4.8. buffer-limit

Specifies:

Maximum size of the buffer for content filtering. -

Type of value:

Size in Kbytes

Default value:

4096

Effect if unset:

Use a 4MB (4096 KB) limit. -

Notes:

For content filtering, i.e. the +filter and - +deanimate-gif actions, it is necessary that - Privoxy buffers the entire document body. - This can be potentially dangerous, since a server could just keep sending - data indefinitely and wait for your RAM to exhaust -- with nasty consequences. - Hence this option. -

When a document buffer size reaches the buffer-limit, it is - flushed to the client unfiltered and no further attempt to - filter the rest of the document is made. Remember that there may be multiple threads - running, which might require up to buffer-limit Kbytes - each, unless you have enabled "single-threaded" - above. -

7.5. Forwarding

This feature allows routing of HTTP requests through a chain of - multiple proxies.

Forwarding can be used to chain Privoxy with a caching proxy to speed - up browsing. Using a parent proxy may also be necessary if the machine - that Privoxy runs on has no direct Internet access.

Note that parent proxies can severely decrease your privacy level. - For example a parent proxy could add your IP address to the request - headers and if it's a caching proxy it may add the "Etag" - header to revalidation requests again, even though you configured Privoxy - to remove it. It may also ignore Privoxy's header time randomization and use the - original values which could be used by the server as cookie replacement - to track your steps between visits.

Also specified here are SOCKS proxies. Privoxy - supports the SOCKS 4 and SOCKS 4A protocols.

7.5.1. forward

Specifies:

To which parent HTTP proxy specific requests should be routed. -

Type of value:

target_pattern - http_parent[:port] -

where target_pattern is a URL pattern - that specifies to which requests (i.e. URLs) this forward rule shall apply. Use / to - denote "all URLs". - http_parent[:port] - is the DNS name or IP address of the parent HTTP proxy through which the requests should be forwarded, - optionally followed by its listening port (default: 8000). - Use a single dot (.) to denote "no forwarding". -

Default value:

Unset

Effect if unset:

Don't use parent HTTP proxies. -

Notes:

If http_parent is ".", then requests are not - forwarded to another HTTP proxy but are made directly to the web servers. -

http_parent can be a - numerical IPv6 address (if - RFC 3493 is - implemented). To prevent clashes with the port delimiter, the whole IP - address has to be put into brackets. On the other hand a target_pattern containing an IPv6 address - has to be put into angle brackets (normal brackets are reserved for - regular expressions already). -

Multiple lines are OK, they are checked in sequence, and the last match wins. -

Examples:

Everything goes to an example parent proxy, except SSL on port 443 (which it doesn't handle): -

  forward   /      parent-proxy.example.org:8080
-  forward   :443   .
-

Everything goes to our example ISP's caching proxy, except for requests - to that ISP's sites: -

  forward   /                  caching-proxy.isp.example.net:8000
-  forward   .isp.example.net   .
-

Parent proxy specified by an IPv6 address: -

  foward   /                   [2001:DB8::1]:8000
-

Suppose your parent proxy doesn't support IPv6: -

+ +
  forward  /                        parent-proxy.example.org:8000
+  debug  8192 # Non-fatal errors
+  debug 32768 # log all data read from the network
+  debug 65536 # Log the applying actions
+
+
+ +

+ To select multiple debug levels, you can either add them or + use multiple debug lines. +

+

+ A debug level of 1 is informative because it will show you + each request as it happens. 1, 1024, 4096 and 8192 are + recommended so that you will notice when things + go wrong. The other levels are probably only of interest if + you are hunting down a specific problem. They can produce a + hell of an output (especially 16). +

+

+ If you are used to the more verbose settings, simply enable + the debug lines below again. +

+

+ If you want to use pure CLF (Common Log Format), you should + set "debug 512" ONLY and not + enable anything else. +

+

+ Privoxy has a hard-coded + limit for the length of log messages. If it's reached, + messages are logged truncated and marked with "... [too long, truncated]". +

+

+ Please don't file any support requests without trying to + reproduce the problem with increased debug level first. + Once you read the log messages, you may even be able to + solve the problem on your own. +

+
+
+
+
+
+

+ 7.3.2. single-threaded +

+
+
+
+ Specifies: +
+
+

+ Whether to run only one server thread. +

+
+
+ Type of value: +
+
+

+ 1 or + 0 +

+
+
+ Default value: +
+
+

+ 0 +

+
+
+ Effect if unset: +
+
+

+ Multi-threaded (or, where unavailable: forked) operation, + i.e. the ability to serve multiple requests simultaneously. +

+
+
+ Notes: +
+
+

+ This option is only there for debugging purposes. It will drastically + reduce performance. +

+
+
+
+
+
+

+ 7.3.3. hostname +

+
+
+
+ Specifies: +
+
+

+ The hostname shown on the CGI pages. +

+
+
+ Type of value: +
+
+

+ Text +

+
+
+ Default value: +
+
+

+ Unset +

+
+
+ Effect if unset: +
+
+

+ The hostname provided by the operating system is used. +

+
+
+ Notes: +
+
+

+ On some misconfigured systems resolving the hostname fails + or takes too much time and slows Privoxy down. Setting a + fixed hostname works around the problem. +

+

+ In other circumstances it might be desirable to show a + hostname other than the one returned by the operating + system. For example if the system has several different + hostnames and you don't want to use the first one. +

+

+ Note that Privoxy does not validate the specified hostname + value. +

+
+
+
+
+
+
+

+ 7.4. Access Control and Security +

+

+ This section of the config file controls the security-relevant + aspects of Privoxy's + configuration. +

+
+

+ 7.4.1. listen-address +

+
+
+
+ Specifies: +
+
+

+ The address and TCP port on which Privoxy will listen for client + requests. +

+
+
+ Type of value: +
+
+

+ [IP-Address]:Port +

+

+ [Hostname]:Port +

+
+
+ Default value: +
+
+

+ 127.0.0.1:8118 +

+
+
+ Effect if unset: +
+
+

+ Bind to 127.0.0.1 (IPv4 localhost), port 8118. This is + suitable and recommended for home users who run Privoxy on the same machine as + their browser. +

+
+
+ Notes: +
+
+

+ You will need to configure your browser(s) to this proxy + address and port. +

+

+ If you already have another service running on port 8118, + or if you want to serve requests from other machines (e.g. + on your local network) as well, you will need to override + the default. +

+

+ You can use this statement multiple times to make Privoxy listen on more ports or + more IP addresses. Suitable if + your operating system does not support sharing IPv6 and IPv4 + protocols on the same socket. +

+

+ If a hostname is used instead of an IP address, Privoxy will try to resolve it + to an IP address and if there are multiple, use the first + one returned. +

+

+ If the address for the hostname isn't already known on the + system (for example because it's in /etc/hostname), this + may result in DNS traffic. +

+

+ If the specified address isn't available on the system, or + if the hostname can't be resolved, Privoxy will fail to start. +

+

+ IPv6 addresses containing colons have to be quoted by + brackets. They can only be used if Privoxy has been compiled with IPv6 + support. If you aren't sure if your version supports it, + have a look at http://config.privoxy.org/show-status. +

+

+ Some operating systems will prefer IPv6 to IPv4 addresses + even if the system has no IPv6 connectivity which is + usually not expected by the user. Some even rely on DNS to + resolve localhost which mean the "localhost" address used + may not actually be local. +

+

+ It is therefore recommended to explicitly configure the + intended IP address instead of relying on the operating + system, unless there's a strong reason not to. +

+

+ If you leave out the address, Privoxy will bind to all IPv4 + interfaces (addresses) on your machine and may become + reachable from the Internet and/or the local network. Be + aware that some GNU/Linux distributions modify that + behaviour without updating the documentation. Check for + non-standard patches if your Privoxy version behaves differently. +

+

+ If you configure Privoxy + to be reachable from the network, consider using access control lists (ACL's, see + below), and/or a firewall. +

+

+ If you open Privoxy to + untrusted users, you will also want to make sure that the + following actions are disabled: enable-edit-actions + and enable-remote-toggle +

+
+
+ Example: +
+
+

+ Suppose you are running Privoxy on a machine which has the + address 192.168.0.1 on your local private network + (192.168.0.0) and has another outside connection with a + different address. You want it to serve requests from + inside only: +

+

+

+ + + + +
+
+  listen-address  192.168.0.1:8118
+
+
+ +

+ Suppose you are running Privoxy on an IPv6-capable machine and + you want it to listen on the IPv6 address of the loopback + device: +

+

+

+ + + + +
+
+  listen-address [::1]:8118
+
+
+
+
+
+
+
+

+ 7.4.2. toggle +

+
+
+
+ Specifies: +
+
+

+ Initial state of "toggle" status +

+
+
+ Type of value: +
+
+

+ 1 or 0 +

+
+
+ Default value: +
+
+

+ 1 +

+
+
+ Effect if unset: +
+
+

+ Act as if toggled on +

+
+
+ Notes: +
+
+

+ If set to 0, Privoxy will + start in "toggled off" mode, + i.e. mostly behave like a normal, content-neutral proxy + with both ad blocking and content filtering disabled. See + enable-remote-toggle below. +

+
+
+
+
+
+

+ 7.4.3. enable-remote-toggle +

+
+
+
+ Specifies: +
+
+

+ Whether or not the web-based + toggle feature may be used +

+
+
+ Type of value: +
+
+

+ 0 or 1 +

+
+
+ Default value: +
+
+

+ 0 +

+
+
+ Effect if unset: +
+
+

+ The web-based toggle feature is disabled. +

+
+
+ Notes: +
+
+

+ When toggled off, Privoxy + mostly acts like a normal, content-neutral proxy, i.e. + doesn't block ads or filter content. +

+

+ Access to the toggle feature can not be controlled separately by + "ACLs" or HTTP authentication, + so that everybody who can access Privoxy (see "ACLs" and listen-address above) can toggle it for all + users. So this option is not recommended for multi-user + environments with untrusted users. +

+

+ Note that malicious client side code (e.g Java) is also + capable of using this option. +

+

+ As a lot of Privoxy users + don't read documentation, this feature is disabled by + default. +

+

+ Note that you must have compiled Privoxy with support for this feature, + otherwise this option has no effect. +

+
+
+
+
+
+

+ 7.4.4. + enable-remote-http-toggle +

+
+
+
+ Specifies: +
+
+

+ Whether or not Privoxy recognizes special HTTP headers to + change its behaviour. +

+
+
+ Type of value: +
+
+

+ 0 or 1 +

+
+
+ Default value: +
+
+

+ 0 +

+
+
+ Effect if unset: +
+
+

+ Privoxy ignores special HTTP headers. +

+
+
+ Notes: +
+
+

+ When toggled on, the client can change Privoxy's behaviour by setting special + HTTP headers. Currently the only supported special header + is "X-Filter: No", to disable + filtering for the ongoing request, even if it is enabled in + one of the action files. +

+

+ This feature is disabled by default. If you are using Privoxy in a environment with + trusted clients, you may enable this feature at your + discretion. Note that malicious client side code (e.g Java) + is also capable of using this feature. +

+

+ This option will be removed in future releases as it has + been obsoleted by the more general header taggers. +

+
+
+
+
+
+

+ 7.4.5. enable-edit-actions +

+
+
+
+ Specifies: +
+
+

+ Whether or not the web-based actions file editor may be used +

+
+
+ Type of value: +
+
+

+ 0 or 1 +

+
+
+ Default value: +
+
+

+ 0 +

+
+
+ Effect if unset: +
+
+

+ The web-based actions file editor is disabled. +

+
+
+ Notes: +
+
+

+ Access to the editor can not be controlled separately by "ACLs" or HTTP authentication, so that + everybody who can access Privoxy (see "ACLs" and listen-address above) can modify its + configuration for all users. +

+

+ This option is not recommended for environments with + untrusted users and as a lot of Privoxy users don't read + documentation, this feature is disabled by default. +

+

+ Note that malicious client side code (e.g Java) is also + capable of using the actions editor and you shouldn't + enable this options unless you understand the consequences + and are sure your browser is configured correctly. +

+

+ Note that you must have compiled Privoxy with support for this feature, + otherwise this option has no effect. +

+
+
+
+
+
+

+ 7.4.6. enforce-blocks +

+
+
+
+ Specifies: +
+
+

+ Whether the user is allowed to ignore blocks and can "go there anyway". +

+
+
+ Type of value: +
+
+

+ 0 or 1 +

+
+
+ Default value: +
+
+

+ 0 +

+
+
+ Effect if unset: +
+
+

+ Blocks are not enforced. +

+
+
+ Notes: +
+
+

+ Privoxy is mainly used to + block and filter requests as a service to the user, for + example to block ads and other junk that clogs the pipes. + Privoxy's configuration + isn't perfect and sometimes innocent pages are blocked. In + this situation it makes sense to allow the user to enforce + the request and have Privoxy ignore the block. +

+

+ In the default configuration Privoxy's "Blocked" page contains a "go there anyway" link to adds a special + string (the force prefix) to the request URL. If that link + is used, Privoxy will + detect the force prefix, remove it again and let the + request pass. +

+

+ Of course Privoxy can also + be used to enforce a network policy. In that case the user + obviously should not be able to bypass any blocks, and + that's what the "enforce-blocks" + option is for. If it's enabled, Privoxy hides the "go there anyway" link. If the user adds the + force prefix by hand, it will not be accepted and the + circumvention attempt is logged. +

+
+
+ Examples: +
+
+

+ enforce-blocks 1 +

+
+
+
+
+
+

+ 7.4.7. ACLs: permit-access and deny-access +

+ +
+
+
+ Specifies: +
+
+

+ Who can access what. +

+
+
+ Type of value: +
+
+

+ src_addr[:port][/src_masklen] [dst_addr[:port][/dst_masklen]] +

+

+ Where src_addr and dst_addr are IPv4 addresses + in dotted decimal notation or valid DNS names, port is a port number, and src_masklen and dst_masklen are subnet masks in + CIDR notation, i.e. integer values from 2 to 30 + representing the length (in bits) of the network address. + The masks and the whole destination part are optional. +

+

+ If your system implements RFC + 3493, then src_addr + and dst_addr can be + IPv6 addresses delimeted by brackets, port can be a number or a service + name, and src_masklen + and dst_masklen can be + a number from 0 to 128. +

+
+
+ Default value: +
+
+

+ Unset +

+

+ If no port is + specified, any port will match. If no src_masklen or src_masklen is given, the + complete IP address has to match (i.e. 32 bits for IPv4 and + 128 bits for IPv6). +

+
+
+ Effect if unset: +
+
+

+ Don't restrict access further than implied by listen-address +

+
+
+ Notes: +
+
+

+ Access controls are included at the request of ISPs and + systems administrators, and are not usually needed by individual + users. For a typical home user, it will normally + suffice to ensure that Privoxy only listens on the localhost + (127.0.0.1) or internal (home) network address by means of + the listen-address option. +

+

+ Please see the warnings in the FAQ that Privoxy is not intended to be a + substitute for a firewall or to encourage anyone to defer + addressing basic security weaknesses. +

+

+ Multiple ACL lines are OK. If any ACLs are specified, Privoxy only talks to IP + addresses that match at least one permit-access line and don't match any + subsequent deny-access line. In + other words, the last match wins, with the default being + deny-access. +

+

+ If Privoxy is using a + forwarder (see forward below) for + a particular destination URL, the dst_addr that is examined is the + address of the forwarder and NOT the address of the ultimate + target. This is necessary because it may be impossible for + the local Privoxy to + determine the IP address of the ultimate target (that's + often what gateways are used for). +

+

+ You should prefer using IP addresses over DNS names, + because the address lookups take time. All DNS names must + resolve! You can not use domain patterns like "*.org" or partial domain names. If a + DNS name resolves to multiple IP addresses, only the first + one is used. +

+

+ Some systems allow IPv4 clients to connect to IPv6 server + sockets. Then the client's IPv4 address will be translated + by the system into IPv6 address space with special prefix + ::ffff:0:0/96 (so called IPv4 mapped IPv6 address). Privoxy can handle it and maps + such ACL addresses automatically. +

+

+ Denying access to particular sites by ACL may have + undesired side effects if the site in question is hosted on + a machine which also hosts other sites (most sites are). +

+
+
+ Examples: +
+
+

+ Explicitly define the default behavior if no ACL and listen-address are set: "localhost" is OK. The absence of a dst_addr implies that all + destination addresses are OK: +

+

+

+ + + + +
+
+  permit-access  localhost
+
+
+ +

+ Allow any host on the same class C subnet as + www.privoxy.org access to nothing but www.example.com (or + other domains hosted on the same system): +

+

+

+ + + + +
+
+  permit-access  www.privoxy.org/24 www.example.com/32
+
+
+ +

+ Allow access from any host on the 26-bit subnet + 192.168.45.64 to anywhere, with the exception that + 192.168.45.73 may not access the IP address behind + www.dirty-stuff.example.com: +

+

+

+ + + + +
+
+  permit-access  192.168.45.64/26
+  deny-access    192.168.45.73    www.dirty-stuff.example.com
+
+
+ +

+ Allow access from the IPv4 network 192.0.2.0/24 even if + listening on an IPv6 wild card address (not supported on + all platforms): +

+

+

+ + + + +
+
+  permit-access  192.0.2.0/24
+
+
+ +

+ This is equivalent to the following line even if listening + on an IPv4 address (not supported on all platforms): +

+

+

+ + + + +
+
+  permit-access  [::ffff:192.0.2.0]/120
+
+
+
+
+
+
+
+

+ 7.4.8. buffer-limit +

+
+
+
+ Specifies: +
+
+

+ Maximum size of the buffer for content filtering. +

+
+
+ Type of value: +
+
+

+ Size in Kbytes +

+
+
+ Default value: +
+
+

+ 4096 +

+
+
+ Effect if unset: +
+
+

+ Use a 4MB (4096 KB) limit. +

+
+
+ Notes: +
+
+

+ For content filtering, i.e. the +filter and +deanimate-gif actions, it is necessary that + Privoxy buffers the entire + document body. This can be potentially dangerous, since a + server could just keep sending data indefinitely and wait + for your RAM to exhaust -- with nasty consequences. Hence + this option. +

+

+ When a document buffer size reaches the buffer-limit, it is flushed to the client + unfiltered and no further attempt to filter the rest of the + document is made. Remember that there may be multiple + threads running, which might require up to buffer-limit Kbytes each, unless you + have enabled "single-threaded" + above. +

+
+
+
+
+
+

+ 7.4.9. + enable-proxy-authentication-forwarding +

+
+
+
+ Specifies: +
+
+

+ Whether or not proxy authentication through Privoxy should work. +

+
+
+ Type of value: +
+
+

+ 0 or 1 +

+
+
+ Default value: +
+
+

+ 0 +

+
+
+ Effect if unset: +
+
+

+ Proxy authentication headers are removed. +

+
+
+ Notes: +
+
+

+ Privoxy itself does not support proxy authentication, but + can allow clients to authenticate against Privoxy's parent + proxy. +

+

+ By default Privoxy (3.0.21 and later) don't do that and + remove Proxy-Authorization headers in requests and + Proxy-Authenticate headers in responses to make it harder + for malicious sites to trick inexperienced users into + providing login information. +

+

+ If this option is enabled the headers are forwarded. +

+

+ Enabling this option is not recommended if there is no parent + proxy that requires authentication or if the local network + between Privoxy and the parent proxy isn't trustworthy. If + proxy authentication is only required for some requests, it + is recommended to use a client header filter to remove the + authentication headers for requests where they aren't + needed. +

+
+
+
+
+
+
+

+ 7.5. Forwarding +

+

+ This feature allows routing of HTTP requests through a chain of + multiple proxies. +

+

+ Forwarding can be used to chain Privoxy with a caching proxy to + speed up browsing. Using a parent proxy may also be necessary if + the machine that Privoxy runs on + has no direct Internet access. +

+

+ Note that parent proxies can severely decrease your privacy level. + For example a parent proxy could add your IP address to the request + headers and if it's a caching proxy it may add the "Etag" header to revalidation requests again, even + though you configured Privoxy to remove it. It may also ignore + Privoxy's header time randomization and use the original values + which could be used by the server as cookie replacement to track + your steps between visits. +

+

+ Also specified here are SOCKS proxies. Privoxy supports the SOCKS 4 and SOCKS 4A + protocols. +

+
+

+ 7.5.1. forward +

+
+
+
+ Specifies: +
+
+

+ To which parent HTTP proxy specific requests should be + routed. +

+
+
+ Type of value: +
+
+

+ target_pattern http_parent[:port] +

+

+ where target_pattern is + a URL pattern + that specifies to which requests (i.e. URLs) this forward + rule shall apply. Use / to denote + "all URLs". http_parent[:port] is the DNS name or IP + address of the parent HTTP proxy through which the requests + should be forwarded, optionally followed by its listening + port (default: 8000). Use a single dot (.) to denote "no + forwarding". +

+
+
+ Default value: +
+
+

+ Unset +

+
+
+ Effect if unset: +
+
+

+ Don't use parent HTTP proxies. +

+
+
+ Notes: +
+
+

+ If http_parent is ".", then requests are not forwarded + to another HTTP proxy but are made directly to the web + servers. +

+

+ http_parent can be a + numerical IPv6 address (if RFC + 3493 is implemented). To prevent clashes with the port + delimiter, the whole IP address has to be put into + brackets. On the other hand a target_pattern containing an IPv6 + address has to be put into angle brackets (normal brackets + are reserved for regular expressions already). +

+

+ Multiple lines are OK, they are checked in sequence, and + the last match wins. +

+
+
+ Examples: +
+
+

+ Everything goes to an example parent proxy, except SSL on + port 443 (which it doesn't handle): +

+

+

+ + + + +
+
+  forward   /      parent-proxy.example.org:8080
+  forward   :443   .
+
+
+ +

+ Everything goes to our example ISP's caching proxy, except + for requests to that ISP's sites: +

+

+

+ + + + +
+
+  forward   /                  caching-proxy.isp.example.net:8000
+  forward   .isp.example.net   .
+
+
+ +

+ Parent proxy specified by an IPv6 address: +

+

+

+ + + + +
+
+  forward   /                   [2001:DB8::1]:8000
+
+
+ +

+ Suppose your parent proxy doesn't support IPv6: +

+

+

+ + +
+
+  forward  /                        parent-proxy.example.org:8000
   forward  ipv6-server.example.org  .
-  forward  <[2-3][0-9a-f][0-9a-f][0-9a-f]:*>   .
-

7.5.2. forward-socks4, forward-socks4a and forward-socks5

Specifies:

Through which SOCKS proxy (and optionally to which parent HTTP proxy) specific requests should be routed. -

Type of value:

target_pattern - socks_proxy[:port] - http_parent[:port] -

where target_pattern is a - URL pattern that specifies to which - requests (i.e. URLs) this forward rule shall apply. Use / to - denote "all URLs". http_parent - and socks_proxy - are IP addresses in dotted decimal notation or valid DNS names - (http_parent - may be "." to denote "no HTTP forwarding"), and the optional - port parameters are TCP ports, - i.e. integer values from 1 to 65535 -

Default value:

Unset

Effect if unset:

Don't use SOCKS proxies. -

Notes:

Multiple lines are OK, they are checked in sequence, and the last match wins. -

The difference between forward-socks4 and forward-socks4a - is that in the SOCKS 4A protocol, the DNS resolution of the target hostname happens on the SOCKS - server, while in SOCKS 4 it happens locally. -

With forward-socks5 the DNS resolution will happen on the remote server as well. -

socks_proxy and - http_parent can be a - numerical IPv6 address (if - RFC 3493 is - implemented). To prevent clashes with the port delimiter, the whole IP - address has to be put into brackets. On the other hand a target_pattern containing an IPv6 address - has to be put into angle brackets (normal brackets are reserved for - regular expressions already). -

If http_parent is ".", then requests are not - forwarded to another HTTP proxy but are made (HTTP-wise) directly to the web servers, albeit through - a SOCKS proxy. -

Examples:

From the company example.com, direct connections are made to all - "internal" domains, but everything outbound goes through - their ISP's proxy by way of example.com's corporate SOCKS 4A gateway to - the Internet. -

  forward-socks4a   /              socks-gw.example.com:1080  www-cache.isp.example.net:8080
-  forward           .example.com   .
-

A rule that uses a SOCKS 4 gateway for all destinations but no HTTP parent looks like this: -

  forward-socks4   /               socks-gw.example.com:1080  .
-

To chain Privoxy and Tor, both running on the same system, you would use - something like: -

  forward-socks5   /               127.0.0.1:9050 .
-

The public Tor network can't be used to - reach your local network, if you need to access local servers you - therefore might want to make some exceptions: -

+ +
  forward         192.168.*.*/     .
+  forward  <[2-3][0-9a-f][0-9a-f][0-9a-f]:*>   .
+
+
+

+
+
+
+
+

+ 7.5.2. forward-socks4, forward-socks4a, + forward-socks5 and forward-socks5t +

+ +
+
+
+ Specifies: +
+
+

+ Through which SOCKS proxy (and optionally to which parent + HTTP proxy) specific requests should be routed. +

+
+
+ Type of value: +
+
+

+ target_pattern socks_proxy[:port] http_parent[:port] +

+

+ where target_pattern is + a URL pattern + that specifies to which requests (i.e. URLs) this forward + rule shall apply. Use / to denote + "all URLs". http_parent and socks_proxy are IP addresses in + dotted decimal notation or valid DNS names (http_parent may be "." to denote "no HTTP + forwarding"), and the optional port parameters are TCP ports, + i.e. integer values from 1 to 65535 +

+
+
+ Default value: +
+
+

+ Unset +

+
+
+ Effect if unset: +
+
+

+ Don't use SOCKS proxies. +

+
+
+ Notes: +
+
+

+ Multiple lines are OK, they are checked in sequence, and + the last match wins. +

+

+ The difference between forward-socks4 and forward-socks4a is that in the SOCKS 4A + protocol, the DNS resolution of the target hostname happens + on the SOCKS server, while in SOCKS 4 it happens locally. +

+

+ With forward-socks5 the DNS + resolution will happen on the remote server as well. +

+

+ forward-socks5t works like vanilla + forward-socks5 but lets Privoxy additionally use + Tor-specific SOCKS extensions. Currently the only supported + SOCKS extension is optimistic data which can reduce the + latency for the first request made on a newly created + connection. +

+

+ socks_proxy and http_parent can be a + numerical IPv6 address (if RFC + 3493 is implemented). To prevent clashes with the port + delimiter, the whole IP address has to be put into + brackets. On the other hand a target_pattern containing an IPv6 + address has to be put into angle brackets (normal brackets + are reserved for regular expressions already). +

+

+ If http_parent is ".", then requests are not forwarded + to another HTTP proxy but are made (HTTP-wise) directly to + the web servers, albeit through a SOCKS proxy. +

+
+
+ Examples: +
+
+

+ From the company example.com, direct connections are made + to all "internal" domains, but + everything outbound goes through their ISP's proxy by way + of example.com's corporate SOCKS 4A gateway to the + Internet. +

+

+

+ + + + +
+
+  forward-socks4a   /              socks-gw.example.com:1080  www-cache.isp.example.net:8080
+  forward           .example.com   .
+
+
+ +

+ A rule that uses a SOCKS 4 gateway for all destinations but + no HTTP parent looks like this: +

+

+

+ + + + +
+
+  forward-socks4   /               socks-gw.example.com:1080  .
+
+
+ +

+ To chain Privoxy and Tor, both running on the same system, + you would use something like: +

+

+

+ + + + +
+
+  forward-socks5t   /               127.0.0.1:9050 .
+
+
+ +

+ Note that if you got Tor through one of the bundles, you + may have to change the port from 9050 to 9150 (or even + another one). For details, please check the documentation + on the Tor + website. +

+

+ The public Tor network + can't be used to reach your local network, if you need to + access local servers you therefore might want to make some + exceptions: +

+

+

+ + +
+
+  forward         192.168.*.*/     .
   forward            10.*.*.*/     .
-  forward           127.*.*.*/     .
-

Unencrypted connections to systems in these address ranges will - be as (un)secure as the local network is, but the alternative is that you - can't reach the local network through Privoxy - at all. Of course this may actually be desired and there is no reason - to make these exceptions if you aren't sure you need them. -

If you also want to be able to reach servers in your local network by - using their names, you will need additional exceptions that look like - this: -

 forward           localhost/     .
-

7.5.3. Advanced Forwarding Examples

If you have links to multiple ISPs that provide various special content - only to their subscribers, you can configure multiple Privoxies - which have connections to the respective ISPs to act as forwarders to each other, so that - your users can see the internal content of all ISPs.

Assume that host-a has a PPP connection to isp-a.example.net. And host-b has a PPP connection to - isp-b.example.org. Both run Privoxy. Their forwarding - configuration can look like this:

host-a:

  forward    /           .
-  forward    .isp-b.example.net  host-b:8118

host-b:

  forward    /           .
-  forward    .isp-a.example.org  host-a:8118

Now, your users can set their browser's proxy to use either - host-a or host-b and be able to browse the internal content - of both isp-a and isp-b.

If you intend to chain Privoxy and - squid locally, then chaining as - browser -> squid -> privoxy is the recommended way.

Assuming that Privoxy and squid - run on the same box, your squid configuration could then look like this:

+ +
  # Define Privoxy as parent proxy (without ICP) 
-  cache_peer 127.0.0.1 parent 8118 7 no-query 
+  forward           127.*.*.*/     .
+
+
+ +

+ Unencrypted connections to systems in these address ranges + will be as (un)secure as the local network is, but the + alternative is that you can't reach the local network + through Privoxy at all. Of + course this may actually be desired and there is no reason + to make these exceptions if you aren't sure you need them. +

+

+ If you also want to be able to reach servers in your local + network by using their names, you will need additional + exceptions that look like this: +

+

+

+ + + + +
+
+ forward           localhost/     .
+
+
+ + +
+
+
+

+ 7.5.3. Advanced Forwarding + Examples +

+

+ If you have links to multiple ISPs that provide various special + content only to their subscribers, you can configure multiple + Privoxies which have connections + to the respective ISPs to act as forwarders to each other, so + that your + users can see the internal content of all ISPs. +

+

+ Assume that host-a has a PPP connection to isp-a.example.net. And + host-b has a PPP connection to isp-b.example.org. Both run Privoxy. Their forwarding + configuration can look like this: +

+

+ host-a: +

+

+

+ + + + +
+
+  forward    /           .
+  forward    .isp-b.example.net  host-b:8118
+
+
+ +

+ host-b: +

+

+

+ + + + +
+
+  forward    /           .
+  forward    .isp-a.example.org  host-a:8118
+
+
+ +

+ Now, your users can set their browser's proxy to use either + host-a or host-b and be able to browse the internal content of + both isp-a and isp-b. +

+

+ If you intend to chain Privoxy + and squid locally, then chaining + as browser -> squid -> privoxy is + the recommended way. +

+

+ Assuming that Privoxy and squid run on the same box, your squid configuration could then look + like this: +

+

+

+ + +
+
+  # Define Privoxy as parent proxy (without ICP)
+  cache_peer 127.0.0.1 parent 8118 7 no-query
 
-  # Define ACL for protocol FTP 
-  acl ftp proto FTP 
+  # Define ACL for protocol FTP
+  acl ftp proto FTP
 
   # Do not forward FTP requests to Privoxy
-  always_direct allow ftp 
+  always_direct allow ftp
 
   # Forward all the rest to Privoxy
-  never_direct allow all

You would then need to change your browser's proxy settings to squid's address and port. - Squid normally uses port 3128. If unsure consult http_port in squid.conf.

You could just as well decide to only forward requests you suspect - of leading to Windows executables through a virus-scanning parent proxy, - say, on antivir.example.com, port 8010:

  forward   /                          .
-  forward   /.*\.(exe|com|dll|zip)$    antivir.example.com:8010

7.5.4. forwarded-connect-retries

Specifies:

How often Privoxy retries if a forwarded connection request fails. -

Type of value:

Number of retries. -

Default value:

0

Effect if unset:

Connections forwarded through other proxies are treated like direct connections and no retry attempts are made. -

Notes:

forwarded-connect-retries is mainly interesting - for socks4a connections, where Privoxy can't detect why the connections failed. - The connection might have failed because of a DNS timeout in which case a retry makes sense, - but it might also have failed because the server doesn't exist or isn't reachable. In this - case the retry will just delay the appearance of Privoxy's error message. -

Note that in the context of this option, "forwarded connections" includes all connections - that Privoxy forwards through other proxies. This option is not limited to the HTTP CONNECT method. -

Only use this option, if you are getting lots of forwarding-related error messages - that go away when you try again manually. Start with a small value and check Privoxy's - logfile from time to time, to see how many retries are usually needed. -

Examples:

forwarded-connect-retries 1 -

7.6. Miscellaneous

7.6.1. accept-intercepted-requests

Specifies:

Whether intercepted requests should be treated as valid. -

Type of value:

0 or 1 -

Default value:

0

Effect if unset:

Only proxy requests are accepted, intercepted requests are treated as invalid. -

Notes:

If you don't trust your clients and want to force them - to use Privoxy, enable this - option and configure your packet filter to redirect outgoing - HTTP connections into Privoxy. -

Make sure that Privoxy's own requests - aren't redirected as well. Additionally take care that - Privoxy can't intentionally connect - to itself, otherwise you could run into redirection loops if - Privoxy's listening port is reachable - by the outside or an attacker has access to the pages you visit. -

Examples:

accept-intercepted-requests 1 -

7.6.2. allow-cgi-request-crunching

Specifies:

Whether requests to Privoxy's CGI pages can be blocked or redirected. -

Type of value:

0 or 1 -

Default value:

0

Effect if unset:

Privoxy ignores block and redirect actions for its CGI pages. -

Notes:

By default Privoxy ignores block or redirect actions - for its CGI pages. Intercepting these requests can be useful in multi-user - setups to implement fine-grained access control, but it can also render the complete - web interface useless and make debugging problems painful if done without care. -

Don't enable this option unless you're sure that you really need it. -

Examples:

allow-cgi-request-crunching 1 -

7.6.3. split-large-forms

Specifies:

Whether the CGI interface should stay compatible with broken HTTP clients. -

Type of value:

0 or 1 -

Default value:

0

Effect if unset:

The CGI form generate long GET URLs. -

Notes:

Privoxy's CGI forms can lead to - rather long URLs. This isn't a problem as far as the HTTP - standard is concerned, but it can confuse clients with arbitrary - URL length limitations. -

Enabling split-large-forms causes Privoxy - to divide big forms into smaller ones to keep the URL length down. - It makes editing a lot less convenient and you can no longer - submit all changes at once, but at least it works around this - browser bug. -

If you don't notice any editing problems, there is no reason - to enable this option, but if one of the submit buttons appears - to be broken, you should give it a try. -

Examples:

split-large-forms 1 -

7.6.4. keep-alive-timeout

Specifies:

Number of seconds after which an open connection will no longer be reused. -

Type of value:

Time in seconds. -

Default value:

None

Effect if unset:

Connections are not kept alive. -

Notes:

This option allows clients to keep the connection to Privoxy - alive. If the server supports it, Privoxy will keep - the connection to the server alive as well. Under certain - circumstances this may result in speed-ups. -

By default, Privoxy will close the connection to the server if - the client connection gets closed, or if the specified timeout - has been reached without a new request coming in. This behaviour - can be changed with the connection-sharing option. -

This option has no effect if Privoxy - has been compiled without keep-alive support. -

Examples:

keep-alive-timeout 300 -

7.6.5. connection-sharing

Specifies:

Whether or not outgoing connections that have been kept alive - should be shared between different incoming connections. -

Type of value:

0 or 1 -

Default value:

None

Effect if unset:

Connections are not shared. -

Notes:

This option has no effect if Privoxy - has been compiled without keep-alive support, or if it's disabled. -

Notes:

Note that reusing connections doesn't necessary cause speedups. - There are also a few privacy implications you should be aware of. -

If this option is effective, outgoing connections are shared between - clients (if there are more than one) and closing the browser that initiated - the outgoing connection does no longer affect the connection between Privoxy - and the server unless the client's request hasn't been completed yet. -

If the outgoing connection is idle, it will not be closed until either - Privoxy's or the server's timeout is reached. - While it's open, the server knows that the system running Privoxy is still - there. -

If there are more than one client (maybe even belonging to multiple users), - they will be able to reuse each others connections. This is potentially - dangerous in case of authentication schemes like NTLM where only the - connection is authenticated, instead of requiring authentication for - each request. -

If there is only a single client, and if said client can keep connections - alive on its own, enabling this option has next to no effect. If the client - doesn't support connection keep-alive, enabling this option may make sense - as it allows Privoxy to keep outgoing connections alive even if the client - itself doesn't support it. -

You should also be aware that enabling this option increases the likelihood - of getting the "No server or forwarder data" error message, especially if you - are using a slow connection to the Internet. -

This option should only be used by experienced users who - understand the risks and can weight them against the benefits. -

Examples:

connection-sharing 1 -

7.6.6. socket-timeout

Specifies:

Number of seconds after which a socket times out if - no data is received. -

Type of value:

Time in seconds. -

Default value:

None

Effect if unset:

A default value of 300 seconds is used. -

Notes:

For SOCKS requests the timeout currently doesn't start until - the SOCKS server accepted the request. This will be fixed in - the next release. -

Examples:

socket-timeout 300 -

7.6.7. max-client-connections

Specifies:

Maximum number of client connections that will be served. -

Type of value:

Positive number. -

Default value:

None

Effect if unset:

Connections are served until a resource limit is reached. -

Notes:

Privoxy creates one thread (or process) for every incoming client - connection that isn't rejected based on the access control settings. -

If the system is powerful enough, Privoxy can theoretically deal with - several hundred (or thousand) connections at the same time, but some - operating systems enforce resource limits by shutting down offending - processes and their default limits may be below the ones Privoxy would - require under heavy load. -

Configuring Privoxy to enforce a connection limit below the thread - or process limit used by the operating system makes sure this doesn't - happen. Simply increasing the operating system's limit would work too, - but if Privoxy isn't the only application running on the system, - you may actually want to limit the resources used by Privoxy. -

If Privoxy is only used by a single trusted user, limiting the - number of client connections is probably unnecessary. If there - are multiple possibly untrusted users you probably still want to - additionally use a packet filter to limit the maximal number of - incoming connections per client. Otherwise a malicious user could - intentionally create a high number of connections to prevent other - users from using Privoxy. -

Obviously using this option only makes sense if you choose a limit - below the one enforced by the operating system. -

Examples:

max-client-connections 256 -

7.7. Windows GUI Options

Privoxy has a number of options specific to the - Windows GUI interface:

If "activity-animation" is set to 1, the - Privoxy icon will animate when - "Privoxy" is active. To turn off, set to 0.

  activity-animation 1
-   

-

If "log-messages" is set to 1, - Privoxy will log messages to the console - window:

  log-messages 1
-   

-

- If "log-buffer-size" is set to 1, the size of the log buffer, - i.e. the amount of memory used for the log messages displayed in the - console window, will be limited to "log-max-lines" (see below).

Warning: Setting this to 0 will result in the buffer to grow infinitely and - eat up all your memory!

  log-buffer-size 1
-   

-

log-max-lines is the maximum number of lines held - in the log buffer. See above.

  log-max-lines 200
-   

-

If "log-highlight-messages" is set to 1, - Privoxy will highlight portions of the log - messages with a bold-faced font:

  log-highlight-messages 1
-   

-

The font used in the console window:

  log-font-name Comic Sans MS
-   

-

Font size used in the console window:

  log-font-size 8
-   

-

- "show-on-task-bar" controls whether or not - Privoxy will appear as a button on the Task bar - when minimized:

  show-on-task-bar 0
-   

-

If "close-button-minimizes" is set to 1, the Windows close - button will minimize Privoxy instead of closing - the program (close with the exit option on the File menu).

  close-button-minimizes 1
-   

-

The "hide-console" option is specific to the MS-Win console - version of Privoxy. If this option is used, - Privoxy will disconnect from and hide the - command console.

  #hide-console
-   

-


PrevHomeNext
Privoxy Configuration Actions Files
+ never_direct allow all +
+
+ +

+ You would then need to change your browser's proxy settings to + squid's address and port. Squid + normally uses port 3128. If unsure consult http_port in squid.conf. +

+

+ You could just as well decide to only forward requests you + suspect of leading to Windows executables through a + virus-scanning parent proxy, say, on antivir.example.com, port 8010: +

+

+

+ + + + +
+
+  forward   /                          .
+  forward   /.*\.(exe|com|dll|zip)$    antivir.example.com:8010
+
+
+
+
+

+ 7.5.4. + forwarded-connect-retries +

+
+
+
+ Specifies: +
+
+

+ How often Privoxy retries if a forwarded connection request + fails. +

+
+
+ Type of value: +
+
+

+ Number of retries. +

+
+
+ Default value: +
+
+

+ 0 +

+
+
+ Effect if unset: +
+
+

+ Connections forwarded through other proxies are treated + like direct connections and no retry attempts are made. +

+
+
+ Notes: +
+
+

+ forwarded-connect-retries is + mainly interesting for socks4a connections, where Privoxy can't detect why the + connections failed. The connection might have failed + because of a DNS timeout in which case a retry makes sense, + but it might also have failed because the server doesn't + exist or isn't reachable. In this case the retry will just + delay the appearance of Privoxy's error message. +

+

+ Note that in the context of this option, "forwarded connections" includes all + connections that Privoxy forwards through other proxies. + This option is not limited to the HTTP CONNECT method. +

+

+ Only use this option, if you are getting lots of + forwarding-related error messages that go away when you try + again manually. Start with a small value and check + Privoxy's logfile from time to time, to see how many + retries are usually needed. +

+
+
+ Examples: +
+
+

+ forwarded-connect-retries 1 +

+
+
+
+
+
+
+

+ 7.6. Miscellaneous +

+
+

+ 7.6.1. + accept-intercepted-requests +

+
+
+
+ Specifies: +
+
+

+ Whether intercepted requests should be treated as valid. +

+
+
+ Type of value: +
+
+

+ 0 or 1 +

+
+
+ Default value: +
+
+

+ 0 +

+
+
+ Effect if unset: +
+
+

+ Only proxy requests are accepted, intercepted requests are + treated as invalid. +

+
+
+ Notes: +
+
+

+ If you don't trust your clients and want to force them to + use Privoxy, enable this + option and configure your packet filter to redirect + outgoing HTTP connections into Privoxy. +

+

+ Note that intercepting encrypted connections (HTTPS) isn't + supported. +

+

+ Make sure that Privoxy's + own requests aren't redirected as well. Additionally take + care that Privoxy can't + intentionally connect to itself, otherwise you could run + into redirection loops if Privoxy's listening port is reachable + by the outside or an attacker has access to the pages you + visit. +

+

+ If you are running Privoxy as intercepting proxy without + being able to intercept all client requests you may want to + adjust the CGI templates to make sure they don't reference + content from config.privoxy.org. +

+
+
+ Examples: +
+
+

+ accept-intercepted-requests 1 +

+
+
+
+
+
+

+ 7.6.2. + allow-cgi-request-crunching +

+
+
+
+ Specifies: +
+
+

+ Whether requests to Privoxy's CGI pages can be blocked or + redirected. +

+
+
+ Type of value: +
+
+

+ 0 or 1 +

+
+
+ Default value: +
+
+

+ 0 +

+
+
+ Effect if unset: +
+
+

+ Privoxy ignores block and + redirect actions for its CGI pages. +

+
+
+ Notes: +
+
+

+ By default Privoxy ignores + block or redirect actions for its CGI pages. Intercepting + these requests can be useful in multi-user setups to + implement fine-grained access control, but it can also + render the complete web interface useless and make + debugging problems painful if done without care. +

+

+ Don't enable this option unless you're sure that you really + need it. +

+
+
+ Examples: +
+
+

+ allow-cgi-request-crunching 1 +

+
+
+
+
+
+

+ 7.6.3. split-large-forms +

+
+
+
+ Specifies: +
+
+

+ Whether the CGI interface should stay compatible with + broken HTTP clients. +

+
+
+ Type of value: +
+
+

+ 0 or 1 +

+
+
+ Default value: +
+
+

+ 0 +

+
+
+ Effect if unset: +
+
+

+ The CGI form generate long GET URLs. +

+
+
+ Notes: +
+
+

+ Privoxy's CGI forms can + lead to rather long URLs. This isn't a problem as far as + the HTTP standard is concerned, but it can confuse clients + with arbitrary URL length limitations. +

+

+ Enabling split-large-forms causes Privoxy to divide big forms into + smaller ones to keep the URL length down. It makes editing + a lot less convenient and you can no longer submit all + changes at once, but at least it works around this browser + bug. +

+

+ If you don't notice any editing problems, there is no + reason to enable this option, but if one of the submit + buttons appears to be broken, you should give it a try. +

+
+
+ Examples: +
+
+

+ split-large-forms 1 +

+
+
+
+
+
+

+ 7.6.4. keep-alive-timeout +

+
+
+
+ Specifies: +
+
+

+ Number of seconds after which an open connection will no + longer be reused. +

+
+
+ Type of value: +
+
+

+ Time in seconds. +

+
+
+ Default value: +
+
+

+ None +

+
+
+ Effect if unset: +
+
+

+ Connections are not kept alive. +

+
+
+ Notes: +
+
+

+ This option allows clients to keep the connection to Privoxy alive. If the server + supports it, Privoxy will + keep the connection to the server alive as well. Under + certain circumstances this may result in speed-ups. +

+

+ By default, Privoxy will + close the connection to the server if the client connection + gets closed, or if the specified timeout has been reached + without a new request coming in. This behaviour can be + changed with the connection-sharing option. +

+

+ This option has no effect if Privoxy has been compiled without + keep-alive support. +

+

+ Note that a timeout of five seconds as used in the default + configuration file significantly decreases the number of + connections that will be reused. The value is used because + some browsers limit the number of connections they open to + a single host and apply the same limit to proxies. This can + result in a single website "grabbing" all the connections the browser + allows, which means connections to other websites can't be + opened until the connections currently in use time out. +

+

+ Several users have reported this as a Privoxy bug, so the + default value has been reduced. Consider increasing it to + 300 seconds or even more if you think your browser can + handle it. If your browser appears to be hanging, it + probably can't. +

+
+
+ Examples: +
+
+

+ keep-alive-timeout 300 +

+
+
+
+
+
+

+ 7.6.5. tolerate-pipelining +

+
+
+
+ Specifies: +
+
+

+ Whether or not pipelined requests should be served. +

+
+
+ Type of value: +
+
+

+ 0 or 1. +

+
+
+ Default value: +
+
+

+ None +

+
+
+ Effect if unset: +
+
+

+ If Privoxy receives more than one request at once, it + terminates the client connection after serving the first + one. +

+
+
+ Notes: +
+
+

+ Privoxy currently doesn't + pipeline outgoing requests, thus allowing pipelining on the + client connection is not guaranteed to improve the + performance. +

+

+ By default Privoxy tries + to discourage clients from pipelining by discarding + aggressively pipelined requests, which forces the client to + resend them through a new connection. +

+

+ This option lets Privoxy + tolerate pipelining. Whether or not that improves + performance mainly depends on the client configuration. +

+

+ If you are seeing problems with pages not properly loading, + disabling this option could work around the problem. +

+
+
+ Examples: +
+
+

+ tolerate-pipelining 1 +

+
+
+
+
+
+

+ 7.6.6. + default-server-timeout +

+
+
+
+ Specifies: +
+
+

+ Assumed server-side keep-alive timeout if not specified by + the server. +

+
+
+ Type of value: +
+
+

+ Time in seconds. +

+
+
+ Default value: +
+
+

+ None +

+
+
+ Effect if unset: +
+
+

+ Connections for which the server didn't specify the + keep-alive timeout are not reused. +

+
+
+ Notes: +
+
+

+ Enabling this option significantly increases the number of + connections that are reused, provided the keep-alive-timeout + option is also enabled. +

+

+ While it also increases the number of connections problems + when Privoxy tries to + reuse a connection that already has been closed on the + server side, or is closed while Privoxy is trying to reuse it, this + should only be a problem if it happens for the first + request sent by the client. If it happens for requests on + reused client connections, Privoxy will simply close the + connection and the client is supposed to retry the request + without bothering the user. +

+

+ Enabling this option is therefore only recommended if the + connection-sharing option is disabled. +

+

+ It is an error to specify a value larger than the keep-alive-timeout + value. +

+

+ This option has no effect if Privoxy has been compiled without + keep-alive support. +

+
+
+ Examples: +
+
+

+ default-server-timeout 60 +

+
+
+
+
+
+

+ 7.6.7. connection-sharing +

+
+
+
+ Specifies: +
+
+

+ Whether or not outgoing connections that have been kept + alive should be shared between different incoming + connections. +

+
+
+ Type of value: +
+
+

+ 0 or 1 +

+
+
+ Default value: +
+
+

+ None +

+
+
+ Effect if unset: +
+
+

+ Connections are not shared. +

+
+
+ Notes: +
+
+

+ This option has no effect if Privoxy has been compiled without + keep-alive support, or if it's disabled. +

+
+
+ Notes: +
+
+

+ Note that reusing connections doesn't necessary cause + speedups. There are also a few privacy implications you + should be aware of. +

+

+ If this option is effective, outgoing connections are + shared between clients (if there are more than one) and + closing the browser that initiated the outgoing connection + does no longer affect the connection between Privoxy and the server unless the + client's request hasn't been completed yet. +

+

+ If the outgoing connection is idle, it will not be closed + until either Privoxy's or + the server's timeout is reached. While it's open, the + server knows that the system running Privoxy is still there. +

+

+ If there are more than one client (maybe even belonging to + multiple users), they will be able to reuse each others + connections. This is potentially dangerous in case of + authentication schemes like NTLM where only the connection + is authenticated, instead of requiring authentication for + each request. +

+

+ If there is only a single client, and if said client can + keep connections alive on its own, enabling this option has + next to no effect. If the client doesn't support connection + keep-alive, enabling this option may make sense as it + allows Privoxy to keep + outgoing connections alive even if the client itself + doesn't support it. +

+

+ You should also be aware that enabling this option + increases the likelihood of getting the "No server or + forwarder data" error message, especially if you are using + a slow connection to the Internet. +

+

+ This option should only be used by experienced users who + understand the risks and can weight them against the + benefits. +

+
+
+ Examples: +
+
+

+ connection-sharing 1 +

+
+
+
+
+
+

+ 7.6.8. socket-timeout +

+
+
+
+ Specifies: +
+
+

+ Number of seconds after which a socket times out if no data + is received. +

+
+
+ Type of value: +
+
+

+ Time in seconds. +

+
+
+ Default value: +
+
+

+ None +

+
+
+ Effect if unset: +
+
+

+ A default value of 300 seconds is used. +

+
+
+ Notes: +
+
+

+ The default is quite high and you probably want to reduce + it. If you aren't using an occasionally slow proxy like + Tor, reducing it to a few seconds should be fine. +

+
+
+ Examples: +
+
+

+ socket-timeout 300 +

+
+
+
+
+
+

+ 7.6.9. + max-client-connections +

+
+
+
+ Specifies: +
+
+

+ Maximum number of client connections that will be served. +

+
+
+ Type of value: +
+
+

+ Positive number. +

+
+
+ Default value: +
+
+

+ 128 +

+
+
+ Effect if unset: +
+
+

+ Connections are served until a resource limit is reached. +

+
+
+ Notes: +
+
+

+ Privoxy creates one thread + (or process) for every incoming client connection that + isn't rejected based on the access control settings. +

+

+ If the system is powerful enough, Privoxy can theoretically deal with + several hundred (or thousand) connections at the same time, + but some operating systems enforce resource limits by + shutting down offending processes and their default limits + may be below the ones Privoxy would require under heavy + load. +

+

+ Configuring Privoxy to + enforce a connection limit below the thread or process + limit used by the operating system makes sure this doesn't + happen. Simply increasing the operating system's limit + would work too, but if Privoxy isn't the only application + running on the system, you may actually want to limit the + resources used by Privoxy. +

+

+ If Privoxy is only used by + a single trusted user, limiting the number of client + connections is probably unnecessary. If there are multiple + possibly untrusted users you probably still want to + additionally use a packet filter to limit the maximal + number of incoming connections per client. Otherwise a + malicious user could intentionally create a high number of + connections to prevent other users from using Privoxy. +

+

+ Obviously using this option only makes sense if you choose + a limit below the one enforced by the operating system. +

+

+ One most POSIX-compliant systems Privoxy can't properly deal with more + than FD_SETSIZE file descriptors at the same time and has + to reject connections if the limit is reached. This will + likely change in a future version, but currently this limit + can't be increased without recompiling Privoxy with a different FD_SETSIZE + limit. +

+
+
+ Examples: +
+
+

+ max-client-connections 256 +

+
+
+
+
+
+

+ 7.6.10. + handle-as-empty-doc-returns-ok +

+
+
+
+ Specifies: +
+
+

+ The status code Privoxy returns for pages blocked with +handle-as-empty-document. +

+
+
+ Type of value: +
+
+

+ 0 or 1 +

+
+
+ Default value: +
+
+

+ 0 +

+
+
+ Effect if unset: +
+
+

+ Privoxy returns a status 403(forbidden) for all blocked + pages. +

+
+
+ Effect if set: +
+
+

+ Privoxy returns a status 200(OK) for pages blocked with + +handle-as-empty-document and a status 403(Forbidden) for + all other blocked pages. +

+
+
+ Notes: +
+
+

+ This directive was added as a work-around for Firefox bug + 492459: "Websites are no longer + rendered if SSL requests for JavaScripts are blocked by a + proxy." (https://bugzilla.mozilla.org/show_bug.cgi?id=492459), + the bug has been fixed for quite some time, but this + directive is also useful to make it harder for websites to + detect whether or not resources are being blocked. +

+
+
+
+
+
+

+ 7.6.11. enable-compression +

+
+
+
+ Specifies: +
+
+

+ Whether or not buffered content is compressed before + delivery. +

+
+
+ Type of value: +
+
+

+ 0 or 1 +

+
+
+ Default value: +
+
+

+ 0 +

+
+
+ Effect if unset: +
+
+

+ Privoxy does not compress buffered content. +

+
+
+ Effect if set: +
+
+

+ Privoxy compresses buffered content before delivering it to + the client, provided the client supports it. +

+
+
+ Notes: +
+
+

+ This directive is only supported if Privoxy has been + compiled with FEATURE_COMPRESSION, which should not to be + confused with FEATURE_ZLIB. +

+

+ Compressing buffered content is mainly useful if Privoxy + and the client are running on different systems. If they + are running on the same system, enabling compression is + likely to slow things down. If you didn't measure + otherwise, you should assume that it does and keep this + option disabled. +

+

+ Privoxy will not compress buffered content below a certain + length. +

+
+
+
+
+
+

+ 7.6.12. compression-level +

+
+
+
+ Specifies: +
+
+

+ The compression level that is passed to the zlib library + when compressing buffered content. +

+
+
+ Type of value: +
+
+

+ Positive number ranging from 0 + to 9. +

+
+
+ Default value: +
+
+

+ 1 +

+
+
+ Notes: +
+
+

+ Compressing the data more takes usually longer than + compressing it less or not compressing it at all. Which + level is best depends on the connection between Privoxy and + the client. If you can't be bothered to benchmark it for + yourself, you should stick with the default and keep + compression disabled. +

+

+ If compression is disabled, the compression level is + irrelevant. +

+
+
+ Examples: +
+
+

+

+ + + + +
+
+    # Best speed (compared to the other levels)
+    compression-level 1
+    # Best compression
+    compression-level 9
+    # No compression. Only useful for testing as the added header
+    # slightly increases the amount of data that has to be sent.
+    # If your benchmark shows that using this compression level
+    # is superior to using no compression at all, the benchmark
+    # is likely to be flawed.
+    compression-level 0
+
+
+
+
+
+
+
+
+

+ 7.6.13. client-header-order +

+
+
+
+ Specifies: +
+
+

+ The order in which client headers are sorted before + forwarding them. +

+
+
+ Type of value: +
+
+

+ Client header names delimited by + spaces or tabs +

+
+
+ Default value: +
+
+

+ None +

+
+
+ Notes: +
+
+

+ By default Privoxy leaves + the client headers in the order they were sent by the + client. Headers are modified in-place, new headers are + added at the end of the already existing headers. +

+

+ The header order can be used to fingerprint client requests + independently of other headers like the User-Agent. +

+

+ This directive allows to sort the headers differently to + better mimic a different User-Agent. Client headers will be + emitted in the order given, headers whose name isn't + explicitly specified are added at the end. +

+

+ Note that sorting headers in an uncommon way will make + fingerprinting actually easier. Encrypted headers are not + affected by this directive. +

+
+
+
+
+
+

+ 7.6.14. client-specific-tag +

+
+
+
+ Specifies: +
+
+

+ The name of a tag that will always be set for clients that + requested it through the webinterface. +

+
+
+ Type of value: +
+
+

+ Tag name followed by a + description that will be shown in the webinterface +

+
+
+ Default value: +
+
+

+ None +

+
+
+ Notes: +
+
+
+ + + + + + + +
+ Warning +
+

+ This is an experimental feature. The syntax is + likely to change in future versions. +

+
+
+

+ Client-specific tags allow Privoxy admins to create + different profiles and let the users chose which one they + want without impacting other users. +

+

+ One use case is allowing users to circumvent certain blocks + without having to allow them to circumvent all blocks. This + is not possible with the enable-remote-toggle + feature because it would bluntly disable all blocks for + all users and also affect other actions like filters. It + also is set globally which renders it useless in most + multi-user setups. +

+

+ After a client-specific tag has been defined with the + client-specific-tag 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! +

+

+ 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. +

+

+ Clients can request tags to be set by using the CGI + interface http://config.privoxy.org/client-tags. + The specific tag description is only used on the web page + and should be phrased in away that the user understand the + effect of the tag. +

+
+
+ Examples: +
+
+

+

+ + + + +
+
+    # Define a couple of tags, the described effect requires action sections
+    # that are enabled based on CLIENT-TAG patterns.
+    client-specific-tag circumvent-blocks Overrule blocks but do not affect other actions
+    disable-content-filters Disable content-filters but do not affect other actions
+
+
+
+
+
+
+
+
+

+ 7.6.15. client-tag-lifetime +

+
+
+
+ Specifies: +
+
+

+ How long a temporarily enabled tag remains enabled. +

+
+
+ Type of value: +
+
+

+ Time in seconds. +

+
+
+ Default value: +
+
+

+ 60 +

+
+
+ Notes: +
+
+
+ + + + + + + +
+ Warning +
+

+ This is an experimental feature. The syntax is + likely to change in future versions. +

+
+
+

+ In case of some tags users may not want to enable them + permanently, but only for a short amount of time, for + example to circumvent a block that is the result of an + overly-broad URL pattern. +

+

+ The CGI interface http://config.privoxy.org/client-tags therefore + provides a "enable this tag temporarily" option. If it is + used, the tag will be set until the client-tag-lifetime is + over. +

+
+
+ Examples: +
+
+

+

+ + + + +
+
+      # Increase the time to life for temporarily enabled tags to 3 minutes
+      client-tag-lifetime 180
+
+
+
+
+
+
+
+
+

+ 7.6.16. trust-x-forwarded-for +

+
+
+
+ Specifies: +
+
+

+ Whether or not Privoxy should use IP addresses specified + with the X-Forwarded-For header +

+
+
+ Type of value: +
+
+

+ 0 or one +

+
+
+ Default value: +
+
+

+ 0 +

+
+
+ Notes: +
+
+
+ + + + + + + +
+ Warning +
+

+ This is an experimental feature. The syntax is + likely to change in future versions. +

+
+
+

+ 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. +

+

+ 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. +

+

+ 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. +

+

+ 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. +

+
+
+ Examples: +
+
+

+

+ + + + +
+
+      # Allow systems that can reach Privoxy to provide the client
+      # IP address with a X-Forwarded-For header.
+      trust-x-forwarded-for 1
+
+
+
+
+
+
+
+
+
+

+ 7.7. Windows GUI Options +

+

+ Privoxy has a number of options + specific to the Windows GUI interface: +

+ +

+ If "activity-animation" is set to 1, the + Privoxy icon will animate when + "Privoxy" is active. To turn off, set to + 0. +

+

+

+

+   activity-animation 1
+    
+

+ +

+ If "log-messages" is set to 1, Privoxy copies log messages to the + console window. The log detail depends on the debug directive. +

+

+

+

+   log-messages 1
+    
+

+ +

+ If "log-buffer-size" is set to 1, the + size of the log buffer, i.e. the amount of memory used for the log + messages displayed in the console window, will be limited to "log-max-lines" (see below). +

+

+ Warning: Setting this to 0 will result in the buffer to grow + infinitely and eat up all your memory! +

+

+

+

+   log-buffer-size 1
+    
+

+ +

+ log-max-lines is the maximum + number of lines held in the log buffer. See above. +

+

+

+

+   log-max-lines 200
+    
+

+ +

+ If "log-highlight-messages" is set to 1, + Privoxy will highlight portions of + the log messages with a bold-faced font: +

+

+

+

+   log-highlight-messages 1
+    
+

+ +

+ The font used in the console window: +

+

+

+

+   log-font-name Comic Sans MS
+    
+

+ +

+ Font size used in the console window: +

+

+

+

+   log-font-size 8
+    
+

+ +

+ "show-on-task-bar" controls whether or + not Privoxy will appear as a + button on the Task bar when minimized: +

+

+

+

+   show-on-task-bar 0
+    
+

+ +

+ If "close-button-minimizes" is set to 1, + the Windows close button will minimize Privoxy instead of closing the program (close + with the exit option on the File menu). +

+

+

+

+   close-button-minimizes 1
+    
+

+ +

+ The "hide-console" option is specific to + the MS-Win console version of Privoxy. If this option is used, Privoxy will disconnect from and hide the + command console. +

+

+

+

+   #hide-console
+    
+

+
+
+ + + +