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.
]]>
@@TITLE@@
Sample Configuration File for Privoxy &p-version;
Copyright (C) 2001-2021 Privoxy Developers https://www.privoxy.org/
##################################################################
#
Table of Contents #
#
I. INTRODUCTION #
II. FORMAT OF THE CONFIGURATION FILE #
#
1. LOCAL SET-UP DOCUMENTATION #
2. CONFIGURATION AND LOG FILE LOCATIONS #
3. DEBUGGING #
4. ACCESS CONTROL AND SECURITY #
5. FORWARDING #
6. MISCELLANEOUS #
7. HTTPS INSPECTION (EXPERIMENTAL) #
8. WINDOWS GUI OPTIONS #
#
##################################################################
I. INTRODUCTION
===============
This file holds Privoxy's main configuration. Privoxy detects
configuration changes automatically, so you don't have to restart it
unless you want to load a different configuration file.
The configuration will be reloaded with the first request after the
change was done, this request itself will still use the old configuration,
though. In other words: it takes two requests before you see the result of
your changes. Requests that are dropped due to ACL don't trigger reloads.
When starting Privoxy on Unix systems, give the location of this
file as last argument. On Windows systems, Privoxy will look for
this file with the name 'config.txt' in the current working directory
of the Privoxy process.
II. FORMAT OF THE CONFIGURATION FILE
====================================
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,
actionsfile default.action
Indicates that the actionsfile is named 'default.action'.
The '#' indicates a comment. Any part of a line following a '#' is
ignored, except if the '#' is preceded by a '\'.
Thus, by placing a # at the start of an existing configuration line,
you can make it a comment and it will be treated as if it weren't there.
This is called "commenting out" an option and can be useful. Removing
the # again is called "uncommenting".
Note that commenting out an option and leaving it at its default
are two completely different things! Most options behave very
differently when unset. See the "Effect if unset" explanation
in each option's description for details.
Long lines can be continued on the next line by using a `\' as
the last character.
]]>
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.
user-manualSpecifies:
Location of the Privoxy User Manual.
Type of value:A fully qualified URIDefault value:UnsetEffect 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/
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.
]]>
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.
]]>
@@#user-manual https://www.privoxy.org/user-manual/]]>
trust-info-urlSpecifies:
A URL to be displayed in the error page that users will see if access to an untrusted page is denied.
Type of value:URLDefault value:UnsetEffect 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!
@@#trust-info-url http://www.example.com/why_we_block.html]]>
@@#trust-info-url http://www.example.com/what_we_allow.html]]>
admin-addressSpecifies:
An email address to reach the Privoxy administrator.
Type of value:Email addressDefault value:UnsetEffect 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.
@@#admin-address privoxy-admin@example.com]]>
proxy-info-urlSpecifies:
A URL to documentation about the local Privoxy setup,
configuration or policies.
Type of value:URLDefault value:UnsetEffect 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 ;-)
@@#proxy-info-url http://www.example.com/proxy-service.html]]>
Configuration and Log File LocationsPrivoxy 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.
confdirSpecifies:The directory where the other configuration files are located.Type of value:Path nameDefault value:/etc/privoxy (Unix) orPrivoxy installation dir (Windows) Effect if unset:MandatoryNotes:
No trailing /, please.
@@confdir .]]>
templdirSpecifies:An alternative directory where the templates are loaded from.Type of value:Path nameDefault value:unsetEffect 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.
@@#templdir .]]>
temporary-directorySpecifies:A directory where Privoxy can create temporary files.Type of value:Path nameDefault value:unsetEffect 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.
@@#temporary-directory .]]>
logdirSpecifies:
The directory where all logging takes place
(i.e. where the logfile is located).
Type of value:Path nameDefault value:/var/log/privoxy (Unix) orPrivoxy installation dir (Windows) Effect if unset:MandatoryNotes:
No trailing /, please.
@@logdir .]]>
actionsfile
Specifies:
The actions file(s) to use
Type of value:Complete file name, relative to confdirDefault values: match-all.action # Actions that are applied to all sites and maybe overruled later on. default.action # Main actions file user.action # User customizationsEffect 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.
@@actionsfile match-all.action # Actions that are applied to all sites and maybe overruled later on.]]>
@@actionsfile default.action # Main actions file]]>
@@actionsfile user.action # User customizations]]>
@@#actionsfile regression-tests.action # Tests for privoxy-regression-test]]>
filterfileSpecifies:
The filter file(s) to use
Type of value:File name, relative to confdirDefault 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.
@@filterfile default.filter]]>
@@filterfile user.filter # User customizations]]>
logfileSpecifies:
The log file to use
Type of value:File name, relative to logdirDefault 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.
@@logfile logfile]]>
trustfileSpecifies:
The name of the trust file to use
Type of value:File name, relative to confdirDefault 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.
@@#trustfile trust]]>
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.
debugSpecifies:
Key values that determine what information gets logged.
Type of value:Integer valuesDefault 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. See also debug 1024.
debug 2 # show each connection status
debug 4 # show tagging-related messages
debug 8 # show header parsing
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 &my-app; didn't let through, and the reason why.
debug 2048 # CGI user interface
debug 4096 # Startup banner and warnings.
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 lot of 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
512ONLY 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.
@@#debug 1 # Log the destination for each request. See also debug 1024.]]>
@@#debug 1024 # Log the destination for requests &my-app; didn't let through, and the reason why.]]>
@@#debug 4096 # Startup banner and warnings]]>
@@#debug 8192 # Non-fatal errors]]>
single-threadedSpecifies:
Whether to run only one server thread.
Type of value:1 or 0Default value:0Effect 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.
@@#single-threaded 1]]>
hostnameSpecifies:
The hostname shown on the CGI pages.
Type of value:TextDefault value:UnsetEffect 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.
@@#hostname hostname.example.org]]>
Access Control and Security
This section of the config file controls the security-relevant aspects
of Privoxy's configuration.
listen-addressSpecifies:
The address and TCP port on which Privoxy will
listen for client requests.
Type of value:[IP-Address]:Port[Hostname]:PortDefault value:127.0.0.1:8118Effect 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.
On GNU/Linux, and other platforms that can listen on not yet assigned IP
addresses, Privoxy will start and will listen on the specified
address whenever the IP address is assigned to the system
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 should
also make sure that the following actions are disabled: enable-edit-actions and
enable-remote-toggleExample:
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
@@listen-address 127.0.0.1:8118]]>
toggleSpecifies:
Initial state of "toggle" status
Type of value:1 or 0Default value:1Effect 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.
@@toggle 1]]>
enable-remote-toggleSpecifies:
Whether or not the web-based toggle
feature may be used
Type of value:0 or 1Default value:0Effect 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.
@@enable-remote-toggle 0]]>
enable-remote-http-toggleSpecifies:
Whether or not Privoxy recognizes special HTTP headers to change its behaviour.
Type of value:0 or 1Default value:0Effect 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.
@@enable-remote-http-toggle 0]]>
enable-edit-actionsSpecifies:
Whether or not the web-based actions
file editor may be used
Type of value:0 or 1Default value:0Effect 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.
@@enable-edit-actions 0]]>
enforce-blocksSpecifies:
Whether the user is allowed to ignore blocks and can go there anyway.
Type of value:0 or 1Default value:0Effect 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'sBlocked 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.
Example:
enforce-blocks 1
@@enforce-blocks 0]]>
ACLs: permit-access and deny-accessSpecifies:
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 delimited 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-addressNotes:
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
buffer-limitSpecifies:
Maximum size of the buffer for content filtering.
Type of value:Size in KbytesDefault value:4096Effect 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.
@@buffer-limit 4096]]>
enable-proxy-authentication-forwardingSpecifies:
Whether or not proxy authentication through &my-app; should work.
Type of value:0 or 1Default value:0Effect 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.
@@enable-proxy-authentication-forwarding 0]]>
trusted-cgi-refererSpecifies:
A trusted website or webpage whose links can be followed to reach sensitive CGI pages
Type of value:URL or URL prefixDefault value:UnsetEffect if unset:
No external pages are considered trusted referers.
Notes:
Before &my-app; accepts configuration changes through CGI pages like
client-tags or the
remote toggle, it checks
the Referer header to see if the request comes from a trusted source.
By default only the webinterface domains
config.privoxy.org
and
p.p
are considered trustworthy.
Requests originating from other domains are rejected to prevent
third-parties from modifiying Privoxy's state by e.g. embedding
images that result in CGI requests.
In some environments it may be desirable to embed links to CGI pages
on external pages, for example on an Intranet homepage the Privoxy admin
controls.
The trusted-cgi-referer option can be used to add that page,
or the whole domain, as trusted source so the resulting requests aren't
rejected.
Requests are accepted if the specified trusted-cgi-refer is the prefix
of the Referer.
If the trusted source is supposed to access the CGI pages via
JavaScript the cors-allowed-origin
option can be used.
Declaring pages the admin doesn't control trustworthy may allow
malicious third parties to modify Privoxy's internal state against
the user's wishes and without the user's knowledge.
@@#trusted-cgi-referer http://www.example.org/local-privoxy-control-page]]>
cors-allowed-originSpecifies:
A trusted website which can access &my-app;'s CGI pages through JavaScript.
Type of value:URLDefault value:UnsetEffect if unset:
No external sites get access via cross-origin resource sharing.
Notes:
Modern browsers by default prevent cross-origin requests made
via JavaScript to &my-app;'s CGI interface even if &my-app;
would trust the referer because it's white listed via the
trusted-cgi-referer
directive.
Cross-origin resource sharing (CORS) is a mechanism to allow
cross-origin requests.
The cors-allowed-origin option can be used to specify
a domain that is allowed to make requests to Privoxy CGI interface
via JavaScript. It is used in combination with the
trusted-cgi-referer
directive.
Declaring domains the admin doesn't control trustworthy may allow
malicious third parties to modify Privoxy's internal state against
the user's wishes and without the user's knowledge.
@@#cors-allowed-origin http://www.example.org/]]>
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.
forwardSpecifies:
To which parent HTTP proxy specific requests should be routed.
Type of value:target_patternhttp_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:UnsetEffect 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]:*> .
forward-socks4, forward-socks4a, forward-socks5 and forward-socks5tSpecifies:
Through which SOCKS proxy (and optionally to which parent HTTP proxy) specific requests should be routed.
Type of value:target_pattern
[user:pass@]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. user and
pass can be used for SOCKS5 authentication if required.
Default value:UnsetEffect 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 &my-app; 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 connect SOCKS5 proxy which requires username/password authentication:
forward-socks5 / user:pass@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/ .
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
# Do not forward FTP requests to Privoxy
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
]]>
forwarded-connect-retriesSpecifies:
How often Privoxy retries if a forwarded connection request fails.
Type of value:Number of retries.Default value:0Effect 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.
Example:
forwarded-connect-retries 1
@@forwarded-connect-retries 0]]>
Miscellaneousaccept-intercepted-requestsSpecifies:
Whether intercepted requests should be treated as valid.
Type of value:0 or 1Default value:0Effect 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.
Example:
accept-intercepted-requests 1
@@accept-intercepted-requests 0]]>
allow-cgi-request-crunchingSpecifies:
Whether requests to Privoxy's CGI pages can be blocked or redirected.
Type of value:0 or 1Default value:0Effect 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.
Example:
allow-cgi-request-crunching 1
@@allow-cgi-request-crunching 0]]>
split-large-formsSpecifies:
Whether the CGI interface should stay compatible with broken HTTP clients.
Type of value:0 or 1Default value:0Effect 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.
Example:
split-large-forms 1
@@split-large-forms 0]]>
keep-alive-timeoutSpecifies:
Number of seconds after which an open connection will no longer be reused.
Type of value:Time in seconds.Default value:NoneEffect if unset:
Connections are not kept alive.
Notes:
This option allows clients to keep the connection to &my-app;
alive. If the server supports it, &my-app; will keep
the connection to the server alive as well. Under certain
circumstances this may result in speed-ups.
By default, &my-app; 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.
Example:
keep-alive-timeout 300
@@keep-alive-timeout 5]]>
tolerate-pipeliningSpecifies:
Whether or not pipelined requests should be served.
Type of value:0 or 1.Default value:NoneEffect if unset:
If Privoxy receives more than one request at once, it terminates the
client connection after serving the first one.
Notes:
&my-app; currently doesn't pipeline outgoing requests,
thus allowing pipelining on the client connection is not
guaranteed to improve the performance.
By default &my-app; 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 &my-app; 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.
Example:
tolerate-pipelining 1
@@tolerate-pipelining 1]]>
default-server-timeoutSpecifies:
Assumed server-side keep-alive timeout if not specified by the server.
Type of value:Time in seconds.Default value:NoneEffect 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 &my-app; tries to reuse a connection that already has
been closed on the server side, or is closed while &my-app;
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, &my-app; 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.
Example:
default-server-timeout 60
@@#default-server-timeout 5]]>
connection-sharingSpecifies:
Whether or not outgoing connections that have been kept alive
should be shared between different incoming connections.
Type of value:0 or 1Default value:NoneEffect 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 enabled, outgoing connections are shared between
clients (if there are more than one) and closing the browser that initiated
the outgoing connection does not affect the connection between &my-app;
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 &my-app; 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 &my-app; 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.
Example:
connection-sharing 1
@@#connection-sharing 1]]>
socket-timeoutSpecifies:
Number of seconds after which a socket times out if
no data is received.
Type of value:Time in seconds.Default value:NoneEffect 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.
When a TLS library is being used to read or write data from a socket with
https-inspection
enabled the socket-timeout currently isn't applied and the timeout
used depends on the library (which may not even use a timeout).
Example:
socket-timeout 300
@@socket-timeout 300]]>
max-client-connectionsSpecifies:
Maximum number of client connections that will be served.
Type of value:Positive number.Default value:128Notes:
Connections are served until a resource limit is reached.
&my-app; 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, &my-app; 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 &my-app; would
require under heavy load.
Configuring &my-app; 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 &my-app; isn't the only application running on the system,
you may actually want to limit the resources used by &my-app;.
If &my-app; 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 &my-app;.
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 &my-app; can't properly deal with
more than FD_SETSIZE file descriptors if &my-app; has been configured
to use select() and has to reject connections if the limit is reached.
When using select() this limit therefore can't be increased without
recompiling &my-app; with a different FD_SETSIZE limit unless &my-app;
is running on Windows with _WIN32 defined.
When &my-app; has been configured to use poll() the FD_SETSIZE limit
does not apply.
Example:
max-client-connections 256
@@#max-client-connections 256]]>
listen-backlogSpecifies:
Connection queue length requested from the operating system.
Type of value:Number.Default value:128Effect if unset:
A connection queue length of 128 is requested from the operating system.
Notes:
Under high load incoming connection may queue up before Privoxy
gets around to serve them. The queue length is limited by the
operating system. Once the queue is full, additional connections
are dropped before Privoxy can accept and serve them.
Increasing the queue length allows Privoxy to accept more
incoming connections that arrive roughly at the same time.
Note that Privoxy can only request a certain queue length,
whether or not the requested length is actually used depends
on the operating system which may use a different length instead.
On many operating systems a limit of -1 can be specified to
instruct the operating system to use the maximum queue length
allowed. Check the listen man page to see if your platform allows this.
On some platforms you can use "netstat -Lan -p tcp" to see the effective
queue length.
Effectively using a value above 128 usually requires changing
the system configuration as well. On FreeBSD-based system the
limit is controlled by the kern.ipc.soacceptqueue sysctl.
Example:
listen-backlog 4096
@@#listen-backlog -1]]>
enable-accept-filterSpecifies:
Whether or not Privoxy should use an accept filter
Type of value:0 or 1Default value:0Effect if unset:
No accept filter is enabled.
Notes:
Accept filters reduce the number of context switches by not
passing sockets for new connections to Privoxy until a complete
HTTP request is available.
As a result, Privoxy can process the whole request right away
without having to wait for additional data first.
For this option to work, Privoxy has to be compiled with
FEATURE_ACCEPT_FILTER and the operating system has to support
it (which may require loading a kernel module).
Currently accept filters are only supported on FreeBSD-based
systems. Check the
accf_http(9)
man page
to learn how to enable the support in the operating system.
Example:
enable-accept-filter 1
@@#enable-accept-filter 1]]>
handle-as-empty-doc-returns-okSpecifies:
The status code Privoxy returns for pages blocked with
+handle-as-empty-document.
Type of value:0 or 1Default value:0Effect 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.
@@#handle-as-empty-doc-returns-ok 1]]>
enable-compressionSpecifies:
Whether or not buffered content is compressed before delivery.
Type of value:0 or 1Default value:0Effect 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.
@@#enable-compression 1]]>
compression-levelSpecifies:
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:1Notes:
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
@@#compression-level 1]]>
client-header-orderSpecifies:
The order in which client headers are sorted before forwarding them.
Type of value:Client header names delimited by spaces or tabsDefault value:NoneNotes:
By default &my-app; 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 unless
https-inspection
is enabled.
@@#client-header-order Host \
User-Agent \
Accept \
Accept-Language \
Accept-Encoding \
Proxy-Connection \
Referer \
Cookie \
DNT \
Connection \
Pragma \
Upgrade-Insecure-Requests \
If-Modified-Since \
Cache-Control \
Content-Length \
Origin \
Content-Type
]]>
client-specific-tagSpecifies:
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 webinterfaceDefault value:NoneNotes:
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 understands 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
client-specific-tag disable-content-filters Disable content-filters but do not affect other actions
client-specific-tag overrule-redirects Overrule redirect sections
client-specific-tag allow-cookies Do not crunch cookies in either direction
client-specific-tag change-tor-socks-port Change forward-socks5 settings to use a different Tor socks port (and circuits)
client-specific-tag no-https-inspection Disable HTTPS inspection
client-specific-tag no-tls-verification Don't verify certificates when http-inspection is enabled
client-tag-lifetimeSpecifies:
How long a temporarily enabled tag remains enabled.
Type of value:Time in seconds.Default value:60Notes:
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.
Example:
# Increase the time to life for temporarily enabled tags to 3 minutes
client-tag-lifetime 180
trust-x-forwarded-forSpecifies:
Whether or not Privoxy should use IP addresses specified with the X-Forwarded-For header
Type of value:0 or oneDefault value:0Notes:
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.
Example:
# Allow systems that can reach Privoxy to provide the client
# IP address with a X-Forwarded-For header.
trust-x-forwarded-for 1
receive-buffer-sizeSpecifies:
The size of the buffer Privoxy uses to receive data from the server.
Type of value:Size in bytesDefault value:5000Notes:
Increasing the receive-buffer-size increases Privoxy's memory usage but
can lower the number of context switches and thereby reduce the
cpu usage and potentially increase the throughput.
This is mostly relevant for fast network connections and
large downloads that don't require filtering.
Reducing the buffer size reduces the amount of memory Privoxy
needs to handle the request but increases the number of systemcalls
and may reduce the throughput.
A dtrace command like:
sudo dtrace -n 'syscall::read:return /execname == "privoxy"/ { @[execname] = llquantize(arg0, 10, 0, 5, 20); @m = max(arg0)}'
can be used to properly tune the receive-buffer-size.
On systems without dtrace, strace or truss may be used as
less convenient alternatives.
If the buffer is too large it will increase Privoxy's memory
footprint without any benefit. As the memory is (currently)
cleared before using it, a buffer that is too large can
actually reduce the throughput.
Example:
# Increase the receive buffer size
receive-buffer-size 32768
HTTPS Inspection (Experimental)
HTTPS inspection allows to filter encrypted requests and responses.
This is only supported when Privoxy
has been built with FEATURE_HTTPS_INSPECTION.
If you aren't sure if your version supports it, have a look at
http://config.privoxy.org/show-status.
ca-directorySpecifies:
Directory with the CA key, the CA certificate and the trusted CAs file.
Type of value:
Text
Default value:Empty stringEffect if unset:
Default value is used.
Notes:
This directive specifies the directory where the
CA key, the CA certificate and the trusted CAs file
are located.
The permissions should only let &my-app; and the &my-app;
admin access the directory.
Example:
ca-directory /usr/local/etc/privoxy/CA
@@#ca-directory /usr/local/etc/privoxy/CA]]>
ca-cert-fileSpecifies:
The CA certificate file in ".crt" format.
Type of value:
Text
Default value:cacert.crtEffect if unset:
Default value is used.
Notes:
This directive specifies the name of the CA certificate file
in ".crt" format.
The file is used by &my-app; to generate website certificates
when https inspection is enabled with the
https-inspection
action.
&my-app; clients should import the certificate so that they
can validate the generated certificates.
The file can be generated with:
openssl req -new -x509 -extensions v3_ca -keyout cakey.pem -out cacert.crt -days 3650Example:
ca-cert-file root.crt
@@#ca-cert-file cacert.crt]]>
ca-key-fileSpecifies:
The CA key file in ".pem" format.
Type of value:
Text
Default value:cacert.pemEffect if unset:
Default value is used.
Notes:
This directive specifies the name of the CA key file in ".pem" format.
The ca-cert-file section contains
a command to generate it.
The CA key is used by &my-app; to sign generated certificates.
Access to the key should be limited to Privoxy.
Example:
ca-key-file cakey.pem
@@#ca-key-file cakey.pem]]>
ca-passwordSpecifies:
The password for the CA keyfile.
Type of value:
Text
Default value:Empty stringEffect if unset:
Default value is used.
Notes:
This directive specifies the password for the CA keyfile
that is used when Privoxy generates certificates for intercepted
requests.
Note that the password is shown on the CGI page so don't
reuse an important one.
Example:
ca-password blafasel
@@#ca-password swordfish]]>
certificate-directorySpecifies:
Directory to save generated keys and certificates.
Type of value:
Text
Default value:./certsEffect if unset:
Default value is used.
Notes:
This directive specifies the directory where generated
TLS/SSL keys and certificates are saved when https inspection
is enabled with the
https-inspection
action.
The keys and certificates currently have to be deleted manually
when changing the ca-cert-file
and the ca-cert-key.
The permissions should only let &my-app; and the &my-app;
admin access the directory.
&my-app; currently does not garbage-collect obsolete keys
and certificates and does not keep track of how may keys
and certificates exist.
&my-app; admins should monitor the size of the directory
and/or make sure there is sufficient space available.
A cron job to limit the number of keys and certificates
to a certain number may be worth considering.
Example:
certificate-directory /usr/local/var/privoxy/certs
@@#certificate-directory /usr/local/var/privoxy/certs]]>
cipher-listSpecifies:
A list of ciphers to use in TLS handshakes
Type of value:
Text
Default value:NoneEffect if unset:
A default value is inherited from the TLS library.
Notes:
This directive allows to specify a non-default list of ciphers to use
in TLS handshakes with clients and servers.
Ciphers are separated by colons. Which ciphers are supported
depends on the TLS library. When using OpenSSL, unsupported ciphers
are skipped. When using MbedTLS they are rejected.
Specifying an unusual cipher list makes fingerprinting easier.
Note that the default list provided by the TLS library may
be unusual when compared to the one used by modern browsers
as well.
Examples:
# Explicitly set a couple of ciphers with names used by MbedTLS
cipher-list cipher-list TLS-ECDHE-RSA-WITH-CHACHA20-POLY1305-SHA256:\
TLS-ECDHE-ECDSA-WITH-CHACHA20-POLY1305-SHA256:\
TLS-DHE-RSA-WITH-CHACHA20-POLY1305-SHA256:\
TLS-ECDHE-ECDSA-WITH-AES-128-GCM-SHA256:\
TLS-ECDHE-ECDSA-WITH-AES-256-GCM-SHA384:\
TLS-ECDHE-ECDSA-WITH-AES-256-CCM:\
TLS-ECDHE-ECDSA-WITH-AES-256-CCM-8:\
TLS-ECDHE-ECDSA-WITH-AES-128-CCM:\
TLS-ECDHE-ECDSA-WITH-AES-128-CCM-8:\
TLS-ECDHE-ECDSA-WITH-CAMELLIA-128-GCM-SHA256:\
TLS-ECDHE-ECDSA-WITH-CAMELLIA-256-GCM-SHA384:\
TLS-ECDHE-RSA-WITH-AES-128-GCM-SHA256:\
TLS-ECDHE-RSA-WITH-AES-256-GCM-SHA384:\
TLS-ECDHE-RSA-WITH-CAMELLIA-128-GCM-SHA256:\
TLS-ECDHE-RSA-WITH-CAMELLIA-256-GCM-SHA384:\
TLS-DHE-RSA-WITH-AES-256-GCM-SHA384:\
TLS-DHE-RSA-WITH-AES-128-GCM-SHA256:\
TLS-DHE-RSA-WITH-AES-256-CCM:\
TLS-DHE-RSA-WITH-AES-256-CCM-8:\
TLS-DHE-RSA-WITH-AES-128-CCM:\
TLS-DHE-RSA-WITH-AES-128-CCM-8:\
TLS-DHE-RSA-WITH-CAMELLIA-128-GCM-SHA256:\
TLS-DHE-RSA-WITH-CAMELLIA-256-GCM-SHA384:\
TLS-ECDH-RSA-WITH-AES-128-GCM-SHA256:\
TLS-ECDH-RSA-WITH-AES-256-GCM-SHA384:\
TLS-ECDH-RSA-WITH-CAMELLIA-128-GCM-SHA256:\
TLS-ECDH-RSA-WITH-CAMELLIA-256-GCM-SHA384:\
TLS-ECDH-ECDSA-WITH-AES-128-GCM-SHA256:\
TLS-ECDH-ECDSA-WITH-AES-256-GCM-SHA384:\
TLS-ECDH-ECDSA-WITH-CAMELLIA-128-GCM-SHA256:\
TLS-ECDH-ECDSA-WITH-CAMELLIA-256-GCM-SHA384
# Explicitly set a couple of ciphers with names used by OpenSSL
cipher-list ECDHE-RSA-AES256-GCM-SHA384:\
ECDHE-ECDSA-AES256-GCM-SHA384:\
DH-DSS-AES256-GCM-SHA384:\
DHE-DSS-AES256-GCM-SHA384:\
DH-RSA-AES256-GCM-SHA384:\
DHE-RSA-AES256-GCM-SHA384:\
ECDH-RSA-AES256-GCM-SHA384:\
ECDH-ECDSA-AES256-GCM-SHA384:\
ECDHE-RSA-AES128-GCM-SHA256:\
ECDHE-ECDSA-AES128-GCM-SHA256:\
DH-DSS-AES128-GCM-SHA256:\
DHE-DSS-AES128-GCM-SHA256:\
DH-RSA-AES128-GCM-SHA256:\
DHE-RSA-AES128-GCM-SHA256:\
ECDH-RSA-AES128-GCM-SHA256:\
ECDH-ECDSA-AES128-GCM-SHA256:\
ECDHE-RSA-AES256-GCM-SHA384:\
AES128-SHA
# Use keywords instead of explicitly naming the ciphers (Does not work with MbedTLS)
cipher-list ALL:!EXPORT:!EXPORT40:!EXPORT56:!aNULL:!LOW:!RC4:@STRENGTH
trusted-cas-fileSpecifies:
The trusted CAs file in ".pem" format.
Type of value:
File name relative to ca-directory
Default value:trustedCAs.pemEffect if unset:
Default value is used.
Notes:
This directive specifies the trusted CAs file that is used when validating
certificates for intercepted TLS/SSL requests.
An example file can be downloaded from
https://curl.se/ca/cacert.pem.
If you want to create the file yourself, please see:
https://curl.se/docs/caextract.html.
Example:
trusted-cas-file trusted_cas_file.pem
@@#trusted-cas-file trustedCAs.pem]]>
Windows GUI OptionsPrivoxy 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]]>
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]]>
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-buffer-size 1
]]>
@@]]>
log-max-lines is the maximum number of lines held
in the log buffer. See above.
@@#log-max-lines 200]]>
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]]>
log-highlight-messages 1
]]>
@@]]>
The font used in the console window:
@@#log-font-name Comic Sans MS]]>
log-font-name Comic Sans MS
]]>
@@]]>
Font size used in the console window:
@@#log-font-size 8]]>
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]]>
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]]>
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]]>
#hide-console
]]>
]]>