X-Git-Url: http://www.privoxy.org/gitweb/?a=blobdiff_plain;ds=sidebyside;f=doc%2Fwebserver%2Fuser-manual%2Factions-file.html;h=f5a98de2db7cf46c68cb935f1385b2153e27a6dc;hb=0f3edd93a652011049e2bfc9b67947f92e236ef8;hp=cbffcee712ef30e84850927870b542f02ef159db;hpb=6d810395712f0337682205c4ea304009c86c128f;p=privoxy.git diff --git a/doc/webserver/user-manual/actions-file.html b/doc/webserver/user-manual/actions-file.html index cbffcee7..f5a98de2 100644 --- a/doc/webserver/user-manual/actions-file.html +++ b/doc/webserver/user-manual/actions-file.html @@ -1,3401 +1,2126 @@ - + -
- -- Privoxy 3.0.18 User Manual - | -
---|
Feature | +Cautious | +Medium | +Advanced | +
---|---|---|---|
Ad-blocking Aggressiveness | +medium | +high | +high | +
Ad-filtering by size | +no | +yes | +yes | +
Ad-filtering by link | +no | +no | +yes | +
Pop-up killing | +blocks only | +blocks only | +blocks only | +
Privacy Features | +low | +medium | +medium/high | +
Cookie handling | +none | +session-only | +kill | +
Referer forging | +no | +yes | +yes | +
GIF de-animation | +no | +yes | +yes | +
Fast redirects | +no | +no | +yes | +
HTML taming | +no | +no | +yes | +
JavaScript taming | +no | +no | +yes | +
Web-bug killing | +no | +yes | +yes | +
Image tag reordering | +no | +yes | +yes | +
The list of actions files to be used are defined in the main configuration file, and are processed in the order + they are defined (e.g. default.action is typically processed before user.action). The content of these can all be viewed and edited from http://config.privoxy.org/show-status. The over-riding + principle when applying actions, is that the last action that matches a given URL wins. The broadest, most general + rules go first (defined in default.action), followed by any exceptions (typically also in + default.action), which are then followed lastly by any local preferences (typically in + user.action). Generally, user.action has the last word.
+An actions file typically has multiple sections. If you want to use "aliases" in an + actions file, you have to place the (optional) alias section at the top of + that file. Then comes the default set of rules which will apply universally to all sites and pages (be very careful with using such a universal set in user.action or any other actions file after default.action, because it + will override the result from consulting any previous file). And then below that, exceptions to the defined + universal policies. You can regard user.action as an appendix to default.action, with the advantage that it is a separate file, which makes preserving your personal + settings across Privoxy upgrades easier.
+Actions can be used to block anything you want, including ads, banners, or just some obnoxious URL whose content + you would rather not see. Cookies can be accepted or rejected, or accepted only during the current browser session + (i.e. not written to disk), content can be modified, some JavaScripts tamed, user-tracking fooled, and much more. + See below for a complete list of actions.
+Note that some actions, like cookie suppression or script disabling, + may render some sites unusable that rely on these techniques to work properly. Finding the right mix of actions + is not always easy and certainly a matter of personal taste. And, things can always change, requiring refinements + in the configuration. In general, it can be said that the more "aggressive" your + default settings (in the top section of the actions file) are, the more exceptions for "trusted" sites you will have to make later. If, for example, you want to crunch all cookies per + default, you'll have to make exceptions from that rule for sites that you regularly use and that require cookies + for actually useful purposes, like maybe your bank, favorite shop, or newspaper.
+We have tried to provide you with reasonable rules to start from in the distribution actions files. But there + is no general rule of thumb on these things. There just are too many variables, and sites are constantly + changing. Sooner or later you will want to change the rules (and read this chapter again :).
+The easiest way to edit the actions files is with a browser by using our browser-based editor, which can be + reached from http://config.privoxy.org/show-status. Note: the config file option enable-edit-actions must be enabled for this to work. The editor allows + both fine-grained control over every single feature on a per-URL basis, and easy choosing from wholesale sets of + defaults like "Cautious", "Medium" or "Advanced". Warning: the "Advanced" setting is more aggressive, and + will be more likely to cause problems for some sites. Experienced users only!
+If you prefer plain text editing to GUIs, you can of course also directly edit the the actions files with your + favorite text editor. Look at default.action which is richly commented with many good + examples.
+Actions files are divided into sections. There are special sections, like the "alias" sections which will be discussed later. For now let's concentrate + on regular sections: They have a heading line (often split up to multiple lines for readability) which consist of + a list of actions, separated by whitespace and enclosed in curly braces. Below that, there is a list of URL and + tag patterns, each on a separate line.
+To determine which actions apply to a request, the URL of the request is compared to all URL patterns in each + "action file". Every time it matches, the list of applicable actions for the request + is incrementally updated, using the heading of the section in which the pattern is located. The same is done + again for tags and tag patterns later on.
+If multiple applying sections set the same action differently, the last match wins. If not, the effects are + aggregated. E.g. a URL might match a regular section with a heading line of { +handle-as-image }, then later another one with just { +block }, resulting in both actions to apply. And there may well be cases where you will want to combine actions + together. Such a section then might look like:
+- Prev - | -- | -- Next + |
+ { +handle-as-image +block{Banner ads.} } + # Block these as if they were images. Send no block page. + banners.example.com + media.example.com/.*banners + .example.com/images/ads/ |
You can trace this process for URL patterns and any given URL by visiting http://config.privoxy.org/show-url-info.
+Examples and more detail on this is provided in the Appendix, Troubleshooting: Anatomy of an Action section.
+As mentioned, Privoxy uses "patterns" to determine + what actions might apply to which sites and pages your + browser attempts to access. These "patterns" use wild card type pattern matching to achieve a high degree of flexibility. This allows + one expression to be expanded and potentially match against many similar patterns.
+Generally, an URL pattern has the form <host><port>/<path>, where + the <host>, the <port> and the <path> are optional. (This is why the special / pattern matches all + URLs). Note that the protocol portion of the URL pattern (e.g. http://) should + not be included in the pattern. This is assumed + already!
+The pattern matching syntax is different for the host and path parts of the URL. The host part uses a simple + globbing type matching technique, while the path part uses more flexible "Regular + Expressions" (POSIX 1003.2).
+The port part of a pattern is a decimal port number preceded by a colon (:). If the + host part contains a numerical IPv6 address, it has to be put into angle brackets (<, + >).
+is a host-only pattern and will match any request to www.example.com, + regardless of which document on that server is requested. So ALL pages in this domain would be covered by + the scope of this action. Note that a simple example.com is different and would + NOT match.
+means exactly the same. For host-only patterns, the trailing / may be + omitted.
+matches all the documents on www.example.com whose name starts with /index.html.
+matches only the single document /index.html on www.example.com.
+matches the document /index.html, regardless of the domain, i.e. on + any web server anywhere.
+Matches any URL because there's no requirement for either the domain or the path to match anything.
+Matches any URL pointing to TCP port 8000.
+Matches any URL with the host address 10.0.0.1. (Note that the real URL uses + plain brackets, not angle brackets.)
+Matches any URL with the host address 2001:db8::1. (Note that the real URL uses + plain brackets, not angle brackets.)
+matches nothing, since it would be interpreted as a domain name and there is no top-level domain called + .html. So its a mistake.
+The matching of the host part offers some flexible options: if the host pattern starts or ends with a dot, + it becomes unanchored at that end. The host pattern is often referred to as domain pattern as it is usually + used to match domain names and not IP addresses. For example:
+matches any domain with first-level domain com and second-level domain + example. For example www.example.com, example.com and foo.bar.baz.example.com. Note that it wouldn't + match if the second-level domain was another-example.
+matches any domain that STARTS with www. (It also matches the domain www but most of the time that + doesn't matter.)
+matches any domain that CONTAINS .example.. And, by the way, also included would be any files or documents that exist + within that domain since no path limitations are specified. (Correctly speaking: It matches any FQDN that + contains example as a domain.) This might be www.example.com, news.example.de, or www.example.net/cgi/testing.pl for instance. All these cases are matched.
+Additionally, there are wild-cards that you can use in the domain names themselves. These work similarly to + shell globbing type wild-cards: "*" represents zero or more arbitrary characters + (this is equivalent to the "Regular Expression" based syntax of ".*"), + "?" represents any single character (this is equivalent to the regular expression + syntax of a simple "."), and you can define "character + classes" in square brackets which is similar to the same regular expression technique. All of this can + be freely mixed:
+matches "adserver.example.com", "ads.example.com", etc but not "sfads.example.com"
+matches all of the above, and then some.
+matches www.ipix.com, pictures.epix.com, a.b.c.d.e.upix.com etc.
+matches www1.example.com, www4.example.cc, + wwwd.example.cy, wwwz.example.com etc., but + not wwww.example.com.
+While flexible, this is not the sophistication of full regular expression based syntax.
+Privoxy uses "modern" POSIX 1003.2 "Regular + Expressions" for matching the path portion (after the slash), and is thus more flexible.
+There is an Appendix with a brief quick-start into regular expressions, + you also might want to have a look at your operating system's documentation on regular expressions (try + man re_format).
+Note that the path pattern is automatically left-anchored at the "/", i.e. it + matches as if it would start with a "^" (regular expression speak for the beginning + of a line).
+Please also note that matching in the path is CASE + INSENSITIVE by default, but you can switch to case sensitive at any point in the pattern by using + the "(?-i)" switch: www.example.com/(?-i)PaTtErN.* will + match only documents whose path starts with PaTtErN in exactly this capitalization.
+Is equivalent to just ".example.com", since any documents within that + domain are matched with or without the ".*" regular expression. This is + redundant
+Will match any page in the domain of "example.com" that is named + "index.html", and that is part of some path. For example, it matches + "www.example.com/testing/index.html" but NOT "www.example.com/index.html" because the regular expression called for at least two + "/'s", thus the path requirement. It also would match "www.example.com/testing/index_html", because of the special meta-character ".".
+This regular expression is conditional so it will match any page named "index.html" regardless of path which in this case can have one or more "/'s". And this one must contain exactly ".html" (and end with + that!).
+This regular expression will match any path of "example.com" that contains + any of the words "ads", "banner", "banners" (because of the "?") or "junk". The path does not have to end in these words, just contain them. The path has to + contain at least two slashes (including the one at the beginning).
+This is very much the same as above, except now it must end in either ".jpg", ".jpeg", ".gif" or + ".png". So this one is limited to common image formats.
+There are many, many good examples to be found in default.action, and more + tutorials below in Appendix on regular expressions.
+Request tag patterns are used to change the applying actions based on the request's tags. Tags can be + created based on HTTP headers with either the client-header-tagger or the server-header-tagger action.
+Request tag patterns have to start with "TAG:", so Privoxy can tell them apart from other patterns. Everything after the colon including + white space, is interpreted as a regular expression with path pattern syntax, except that tag patterns aren't + left-anchored automatically (Privoxy doesn't silently add a "^", you have to do it yourself if you need it).
+To match all requests that are tagged with "foo" your pattern line should be + "TAG:^foo$", "TAG:foo" would work as well, but it would + also match requests whose tags contain "foo" somewhere. "TAG: + foo" wouldn't work as it requires white space.
+Sections can contain URL and request tag patterns at the same time, but request tag patterns are checked + after the URL patterns and thus always overrule them, even if they are located before the URL patterns.
+Once a new request tag is added, Privoxy checks right away if it's matched by one of the request tag + patterns and updates the action settings accordingly. As a result request tags can be used to activate other + tagger actions, as long as these other taggers look for headers that haven't already be parsed.
+For example you could tag client requests which use the POST method, then use this + tag to activate another tagger that adds a tag if cookies are sent, and then use a block action based on the + cookie tag. This allows the outcome of one action, to be input into a subsequent action. However if you'd + reverse the position of the described taggers, and activated the method tagger based on the cookie tagger, no + method tags would be created. The method tagger would look for the request line, but at the time the cookie tag + is created, the request line has already been parsed.
+While this is a limitation you should be aware of, this kind of indirection is seldom needed anyway and even + the example doesn't make too much sense.
+To match requests that do not have a certain request tag, specify a negative tag pattern by prefixing the + tag pattern line with either "NO-REQUEST-TAG:" or "NO-RESPONSE-TAG:" instead of "TAG:".
+Negative request tag patterns created with "NO-REQUEST-TAG:" are checked after + all client headers are scanned, the ones created with "NO-RESPONSE-TAG:" are checked + after all server headers are scanned. In both cases all the created tags are considered.
+Warning | +
+ This is an experimental feature. The syntax is likely to change in future versions. + |
+
Client tag patterns are not set based on HTTP headers but based on the client's IP address. Users can enable + them themselves, but the Privoxy admin controls which tags are available and what their effect is.
+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.
+Example:
+
+ # If the admin defined the client-specific-tag circumvent-blocks, +# and the request comes from a client that previously requested +# the tag to be set, overrule all previous +block actions that +# are enabled based on URL to CLIENT-TAG patterns. +{-block} +CLIENT-TAG:^circumvent-blocks$ + +# This section is not overruled because it's located after +# the previous one. +{+block{Nobody is supposed to request this.}} +example.org/blocked-example-page+ |
+
- The actions files are used to define what actions Privoxy takes for which URLs, and thus - determines how ad images, cookies and various other aspects of HTTP - content and transactions are handled, and on which sites (or even - parts thereof). There are a number of such actions, with a wide range - of functionality. Each action does something a little different. - These actions give us a veritable arsenal of tools with which to - exert our control, preferences and independence. Actions can be - combined so that their effects are aggregated when applied against a - given set of URLs. -
-- There are three action files included with Privoxy with differing purposes: -
--
+All actions are disabled by default, until they are explicitly enabled somewhere in an actions file. Actions + are turned on if preceded with a "+", and turned off if preceded with a "-". So a +action means "do that action", e.g. + +block means "please block URLs that match the following + patterns", and -block means "don't block URLs that match the + following patterns, even if +block previously applied."
+Again, actions are invoked by placing them on a line, enclosed in curly braces and separated by whitespace, + like in {+some-action -some-other-action{some-parameter}}, followed by a list of URL + patterns, one per line, to which they apply. Together, the actions line and the following pattern lines make up a + section of the actions file.
+Actions fall into three categories:
- match-all.action - is used to define - which "actions" relating to - banner-blocking, images, pop-ups, content modification, cookie - handling etc should be applied by default. It should be the first - actions file loaded -
+Boolean, i.e the action can only be "enabled" or "disabled". Syntax:
+
+ +name # enable action name + -name # disable action name+ |
+
Example: +handle-as-image
- default.action - defines many - exceptions (both positive and negative) from the default set of - actions that's configured in match-all.action. It is a set of rules that - should work reasonably well as-is for most users. This file is - only supposed to be edited by the developers. It should be the - second actions file loaded. -
+Parameterized, where some value is required in order to enable this type of action. Syntax:
+
+ +name{param} # enable action and set parameter to param, + # overwriting parameter from previous match if necessary + -name # disable action. The parameter can be omitted+ |
+
Note that if the URL matches multiple positive forms of a parameterized action, the last match wins, i.e. + the params from earlier matches are simply ignored.
+Example: +hide-user-agent{Mozilla/5.0 (X11; U; FreeBSD i386; en-US; rv:1.8.1.4) + Gecko/20070602 Firefox/2.0.0.4}
- user.action - is intended to be for - local site preferences and exceptions. As an example, if your ISP - or your bank has specific requirements, and need special - handling, this kind of thing should go here. This file will not - be upgraded. -
+Multi-value. These look exactly like parameterized actions, but they behave differently: If the action + applies multiple times to the same URL, but with different parameters, all the parameters from all + matches are remembered. This is used for actions that can be executed for the same request repeatedly, like + adding multiple headers, or filtering through multiple filters. Syntax:
+
+ +name{param} # enable action and add param to the list of parameters + -name{param} # remove the parameter param from the list of parameters + # If it was the last one left, disable the action. + -name # disable this action completely and remove all parameters from the list+ |
+
Examples: +add-header{X-Fun-Header: Some text} and +filter{html-annoyances}
- Edit Set - to Cautious Set to Medium - Set to Advanced -
-- These have increasing levels of aggressiveness and have no influence on your - browsing unless you select them explicitly in the - editor. A default installation should be pre-set to - Cautious. New users should try this for - a while before adjusting the settings to more aggressive levels. - The more aggressive the settings, then the more likelihood there - is of problems such as sites not working as they should. -
-- The Edit button allows you to turn - each action on/off individually for fine-tuning. The Cautious button changes the actions list to - low/safe settings which will activate ad blocking and a minimal - set of Privoxy's features, and - subsequently there will be less of a chance for accidental - problems. The Medium button sets - the list to a medium level of other features and a low level set - of privacy features. The Advanced - button sets the list to a high level of ad blocking and medium - level of privacy. See the chart below. The latter three buttons - over-ride any changes via with the Edit button. More fine-tuning can be done in - the lower sections of this internal page. -
-- While the actions file editor allows to enable these settings in - all actions files, they are only supposed to be enabled in the - first one to make sure you don't unintentionally overrule earlier - rules. -
-- The default profiles, and their associated actions, as - pre-defined in default.action are: -
--
-- Table 1. Default Configurations -
-- Feature - | -- Cautious - | -- Medium - | -- Advanced - | -
---|
- Ad-blocking Aggressiveness - | -- medium - | -- high - | -
- high
+ # Add a DNT ("Do not track") header to all requests, +# event to those that already have one. +# +# This is just an example, not a recommendation. +# +# There is no reason to believe that user-tracking websites care +# about the DNT header and depending on the User-Agent, adding the +# header may make user-tracking easier. +{+add-header{DNT: 1}} +/ |
Block ads or other unwanted content
+Requests for URLs to which this action applies are blocked, i.e. the requests are trapped by + Privoxy and the requested URL is never retrieved, but is answered + locally with a substitute page or image, as determined by the handle-as-image, set-image-blocker, and handle-as-empty-document actions.
+Parameterized.
+A block reason that should be given to the user.
+Privoxy sends a special "BLOCKED" page for + requests to blocked pages. This page contains the block reason given as parameter, a link to find out why + the block action applies, and a click-through to the blocked content (the latter only if the force + feature is available and enabled).
+A very important exception occurs if both + block and handle-as-image, apply to the same request: it will then be + replaced by an image. If set-image-blocker (see below) also applies, the type of + image will be determined by its parameter, if not, the standard checkerboard pattern is sent.
+It is important to understand this process, in order to understand how Privoxy deals with ads and other unwanted content. Blocking is a core feature, and + one upon which various other features depend.
+The filter action can perform a very + similar task, by "blocking" banner images and other content through rewriting + the relevant URLs in the document's HTML source, so they don't get requested in the first place. Note + that this is a totally different technique, and it's easy to confuse the two.
+- Ad-filtering by size - | -- no - | -- yes - | -
- yes
+ {+block{No nasty stuff for you.}} +# Block and replace with "blocked" page + .nasty-stuff.example.com + +{+block{Doubleclick banners.} +handle-as-image} +# Block and replace with image + .ad.doubleclick.net + .ads.r.us/banners/ + +{+block{Layered ads.} +handle-as-empty-document} +# Block and then ignore + adserver.example.net/.*\.js$ |
Improve privacy by not forwarding the source of the request in the HTTP headers.
+Deletes the "X-Forwarded-For:" HTTP header from the client request, or adds + a new one.
+Parameterized.
+"block" to delete the header.
+"add" to create the header (or append the client's IP address to an + already existing one).
+It is safe and recommended to use block.
+Forwarding the source address of the request may make sense in some multi-user setups but is also a + privacy risk.
+
- Ad-filtering by link
+ +change-x-forwarded-for{block} |
+
Rewrite or remove single client headers.
+All client headers to which this action applies are filtered on-the-fly through the specified regular + expression based substitutions.
+Multi-value.
+The name of a client-header filter, as defined in one of the filter + files.
+Client-header filters are applied to each header on its own, not to all at once. This makes it easier + to diagnose problems, but on the downside you can't write filters that only change header x if header y's + value is z. You can do that by using tags though.
+Client-header filters are executed after the other header actions have finished and use their output + as input.
+If the request URI gets changed, Privoxy will detect that and use the + new one. This can be used to rewrite the request destination behind the client's back, for example to + specify a Tor exit relay for certain requests.
+Please refer to the filter file chapter to learn which client-header + filters are available by default, and how to create your own.
+
- no
+ # Hide Tor exit notation in Host and Referer Headers +{+client-header-filter{hide-tor-exit-notation}} +/ |
+
Block requests based on their headers.
+Client headers to which this action applies are filtered on-the-fly through the specified regular + expression based substitutions, the result is used as tag.
+Multi-value.
+The name of a client-header tagger, as defined in one of the filter + files.
+Client-header taggers are applied to each header on its own, and as the header isn't modified, each + tagger "sees" the original.
+Client-header taggers are the first actions that are executed and their tags can be used to control + every other action.
+
- no
+ # Tag every request with the User-Agent header +{+client-header-tagger{user-agent}} +/ + +# Tagging itself doesn't change the action +# settings, sections with TAG patterns do: +# +# If it's a download agent, use a different forwarding proxy, +# show the real User-Agent and make sure resume works. +{+forward-override{forward-socks5 10.0.0.2:2222 .} \ + -hide-if-modified-since \ + -overwrite-last-modified \ + -hide-user-agent \ + -filter \ + -deanimate-gifs \ +} +TAG:^User-Agent: NetBSD-ftp/ +TAG:^User-Agent: Novell ZYPP Installer +TAG:^User-Agent: RPM APT-HTTP/ +TAG:^User-Agent: fetch libfetch/ +TAG:^User-Agent: Ubuntu APT-HTTP/ +TAG:^User-Agent: MPlayer/ |
+
- yes
+ # Tag all requests with the Range header set +{+client-header-tagger{range-requests}} +/ + +# Disable filtering for the tagged requests. +# +# With filtering enabled Privoxy would remove the Range headers +# to be able to filter the whole response. The downside is that +# it prevents clients from resuming downloads or skipping over +# parts of multimedia files. +{-filter -deanimate-gifs} +TAG:^RANGE-REQUEST$ |
- Pop-up killing - | -- blocks only - | -- blocks only - | -
- blocks only
+ # Tag all requests with the client IP address +# +# (Technically the client IP address isn't included in the +# client headers but client-header taggers can set it anyway. +# For details see the tagger in default.filter) +{+client-header-tagger{client-ip-address}} +/ + +# Change forwarding settings for requests coming from address 10.0.0.1 +{+forward-override{forward-socks5 127.0.1.2:2222 .}} +TAG:^IP-ADDRESS: 10\.0\.0\.1$ |
Stop useless download menus from popping up, or change the browser's rendering mode
+Replaces the "Content-Type:" HTTP server header.
+Parameterized.
+Any string.
+The "Content-Type:" HTTP server header is used by the browser to decide + what to do with the document. The value of this header can cause the browser to open a download menu + instead of displaying the document by itself, even if the document's format is supported by the + browser.
+The declared content type can also affect which rendering mode the browser chooses. If XHTML is + delivered as "text/html", many browsers treat it as yet another broken HTML + document. If it is send as "application/xml", browsers with XHTML support will + only display it, if the syntax is correct.
+If you see a web site that proudly uses XHTML buttons, but sets "Content-Type: + text/html", you can use Privoxy to overwrite it with "application/xml" and validate the web master's claim inside your XHTML-supporting + browser. If the syntax is incorrect, the browser will complain loudly.
+You can also go the opposite direction: if your browser prints error messages instead of rendering a + document falsely declared as XHTML, you can overwrite the content type with "text/html" and have it rendered as broken HTML document.
+By default content-type-overwrite only replaces "Content-Type:" headers that look like some kind of text. If you want to overwrite it + unconditionally, you have to combine it with force-text-mode. This limitation exists for a reason, think + twice before circumventing it.
+Most of the time it's easier to replace this action with a custom server-header filter. It allows you to activate it for + every document of a certain site and it will still only replace the content types you aimed at.
+Of course you can apply content-type-overwrite to a whole site and then make + URL based exceptions, but it's a lot more work to get the same precision.
+- Privacy Features - | -- low - | -- medium - | -
- medium/high
+ # Check if www.example.net/ really uses valid XHTML +{ +content-type-overwrite{application/xml} } +www.example.net/ + +# but leave the content type unmodified if the URL looks like a style sheet +{-content-type-overwrite} +www.example.net/.*\.css$ +www.example.net/.*style |
Remove a client header Privoxy has no dedicated action for.
+Deletes every header sent by the client that contains the string the user supplied as parameter.
+Parameterized.
+Any string.
+This action allows you to block client headers for which no dedicated Privoxy action exists. Privoxy will remove every + client header that contains the string you supplied as parameter.
+Regular expressions are not supported and you + can't use this action to block different headers in the same request, unless they contain the same + string.
+crunch-client-header is only meant for quick tests. If you have to block + several different headers, or only want to modify parts of them, you should use a client-header filter.
+Warning | +
+ Don't block any header without understanding the consequences. + |
+
- Cookie handling - | -- none - | -- session-only - | -
- kill
+ # Block the non-existent "Privacy-Violation:" client header +{ +crunch-client-header{Privacy-Violation:} } +/ |
Prevent yet another way to track the user's steps between sessions.
+Deletes the "If-None-Match:" HTTP client header.
+Boolean.
+N/A
+Removing the "If-None-Match:" HTTP client header is useful for filter + testing, where you want to force a real reload instead of getting status code "304" which would cause the browser to use a cached copy of the page.
+It is also useful to make sure the header isn't used as a cookie replacement (unlikely but + possible).
+Blocking the "If-None-Match:" header shouldn't cause any caching problems, + as long as the "If-Modified-Since:" header isn't blocked or missing as + well.
+It is recommended to use this action together with hide-if-modified-since and overwrite-last-modified.
+- Referer forging - | -- no - | -- yes - | -
- yes
+ # Let the browser revalidate cached documents but don't +# allow the server to use the revalidation headers for user tracking. +{+hide-if-modified-since{-60} \ + +overwrite-last-modified{randomize} \ + +crunch-if-none-match} +/ |
Prevent the web server from setting HTTP cookies on your system
+Deletes any "Set-Cookie:" HTTP headers from server replies.
+Boolean.
+N/A
+This action is only concerned with incoming HTTP + cookies. For outgoing HTTP cookies, use crunch-outgoing-cookies. Use + both to disable HTTP cookies completely.
+It makes no sense at all to use this action in + conjunction with the session-cookies-only action, since it would prevent the + session cookies from being set. See also filter-content-cookies.
+- GIF de-animation - | -- no - | -- yes - | -
- yes
+ +crunch-incoming-cookies |
Remove a server header Privoxy has no dedicated action for.
+Deletes every header sent by the server that contains the string the user supplied as parameter.
+Parameterized.
+Any string.
+This action allows you to block server headers for which no dedicated Privoxy action exists. Privoxy will remove every + server header that contains the string you supplied as parameter.
+Regular expressions are not supported and you + can't use this action to block different headers in the same request, unless they contain the same + string.
+crunch-server-header is only meant for quick tests. If you have to block + several different headers, or only want to modify parts of them, you should use a custom server-header filter.
+Warning | +
+ Don't block any header without understanding the consequences. + |
+
- Fast redirects - | -- no - | -- no - | -
- yes
+ # Crunch server headers that try to prevent caching +{ +crunch-server-header{no-cache} } +/ |
Prevent the web server from reading any HTTP cookies from your system
+Deletes any "Cookie:" HTTP headers from client requests.
+Boolean.
+N/A
+This action is only concerned with outgoing HTTP + cookies. For incoming HTTP cookies, use crunch-incoming-cookies. Use + both to disable HTTP cookies completely.
+It makes no sense at all to use this action in + conjunction with the session-cookies-only action, since it would prevent the + session cookies from being read.
+- HTML taming - | -- no - | -- no - | -
- yes
+ +crunch-outgoing-cookies |
Stop those annoying, distracting animated GIF images.
+De-animate GIF animations, i.e. reduce them to their first or last image.
+Parameterized.
+"last" or "first"
+This will also shrink the images considerably (in bytes, not pixels!). If the option "first" is given, the first frame of the animation is used as the replacement. If + "last" is given, the last frame of the animation is used instead, which + probably makes more sense for most banner animations, but also has the risk of not showing the entire + last frame (if it is only a delta to an earlier frame).
+You can safely use this action with patterns that will also match non-GIF objects, because no attempt + will be made at anything that doesn't look like a GIF.
+- JavaScript taming - | -- no - | -- no - | -
- yes
+ +deanimate-gifs{last} |
Delay responses to the client to reduce the load
+Delays responses to the client by sending the response in ca. 10 byte chunks.
+Parameterized.
+"Number of milliseconds"
+Sometimes when JavaScript code is used to fetch advertisements it doesn't respect Privoxy's blocks and + retries to fetch the same resource again causing unnecessary load on the client.
+This action delays responses to the client and can be combined with blocks to slow down the JavaScript code, thus reducing the load on the + client.
+When used without blocks the action can + also be used to simulate a slow internet connection.
+- Web-bug killing - | -- no - | -- yes - | -
- yes
+ +delay-response{100} |
Work around (very rare) problems with HTTP/1.1
+Downgrades HTTP/1.1 client requests and server replies to HTTP/1.0.
+Boolean.
+N/A
+This is a left-over from the time when Privoxy didn't support + important HTTP/1.1 features well. It is left here for the unlikely case that you experience + HTTP/1.1-related problems with some server out there.
+Note that enabling this action is only a workaround. It should not be enabled for sites that work + without it. While it shouldn't break any pages, it has an (usually negative) performance impact.
+If you come across a site where enabling this action helps, please report it, so the cause of the + problem can be analyzed. If the problem turns out to be caused by a bug in Privoxy it should be fixed so the following release works without the work + around.
+- Image tag reordering - | -- no - | -- yes - | -
- yes
+ {+downgrade-http-version} +problem-host.example.com |
- The list of actions files to be used are defined in the main - configuration file, and are processed in the order they are defined - (e.g. default.action is typically processed - before user.action). The content of these - can all be viewed and edited from http://config.privoxy.org/show-status. The over-riding - principle when applying actions, is that the last action that matches - a given URL wins. The broadest, most general rules go first (defined - in default.action), followed by any - exceptions (typically also in default.action), which are then followed lastly by - any local preferences (typically in user.action). - Generally, user.action has the last word. -
-- An actions file typically has multiple sections. If you want to use - "aliases" in an actions file, you have to - place the (optional) alias - section at the top of that file. Then comes the default set of - rules which will apply universally to all sites and pages (be very careful with - using such a universal set in user.action - or any other actions file after default.action, because it will override the result - from consulting any previous file). And then below that, exceptions - to the defined universal policies. You can regard user.action as an appendix to default.action, with the advantage that it is a - separate file, which makes preserving your personal settings across - Privoxy upgrades easier. -
-- Actions can be used to block anything you want, including ads, - banners, or just some obnoxious URL whose content you would rather - not see. Cookies can be accepted or rejected, or accepted only during - the current browser session (i.e. not written to disk), content can - be modified, some JavaScripts tamed, user-tracking fooled, and much - more. See below for a complete - list of actions. -
-- Note that some actions, - like cookie suppression or script disabling, may render some sites - unusable that rely on these techniques to work properly. Finding - the right mix of actions is not always easy and certainly a matter - of personal taste. And, things can always change, requiring - refinements in the configuration. In general, it can be said that - the more "aggressive" your default - settings (in the top section of the actions file) are, the more - exceptions for "trusted" sites you will - have to make later. If, for example, you want to crunch all cookies - per default, you'll have to make exceptions from that rule for - sites that you regularly use and that require cookies for actually - useful purposes, like maybe your bank, favorite shop, or newspaper. -
-- We have tried to provide you with reasonable rules to start from in - the distribution actions files. But there is no general rule of - thumb on these things. There just are too many variables, and sites - are constantly changing. Sooner or later you will want to change - the rules (and read this chapter again :). -
-- The easiest way to edit the actions files is with a browser by - using our browser-based editor, which can be reached from http://config.privoxy.org/show-status. Note: the config - file option enable-edit-actions must be - enabled for this to work. The editor allows both fine-grained - control over every single feature on a per-URL basis, and easy - choosing from wholesale sets of defaults like "Cautious", "Medium" or - "Advanced". Warning: the "Advanced" setting is more aggressive, and will be - more likely to cause problems for some sites. Experienced users - only! -
-- If you prefer plain text editing to GUIs, you can of course also - directly edit the the actions files with your favorite text editor. - Look at default.action which is richly - commented with many good examples. -
+- Actions files are divided into sections. There are special - sections, like the "alias" sections which will - be discussed later. For now let's concentrate on regular sections: - They have a heading line (often split up to multiple lines for - readability) which consist of a list of actions, separated by - whitespace and enclosed in curly braces. Below that, there is a - list of URL and tag patterns, each on a separate line. -
-- To determine which actions apply to a request, the URL of the - request is compared to all URL patterns in each "action file". Every time it matches, the list of - applicable actions for the request is incrementally updated, using - the heading of the section in which the pattern is located. The - same is done again for tags and tag patterns later on. -
-- If multiple applying sections set the same action differently, the - last match wins. If not, the effects are aggregated. E.g. a URL - might match a regular section with a heading line of { +handle-as-image }, - then later another one with just { +block }, resulting in both actions to - apply. And there may well be cases where you will want to combine - actions together. Such a section then might look like: -
--
-
-- { +handle-as-image +block{Banner ads.} } - # Block these as if they were images. Send no block page. - banners.example.com - media.example.com/.*banners - .example.com/images/ads/ -- |
-
- You can trace this process for URL patterns and any given URL by - visiting http://config.privoxy.org/show-url-info. -
-- Examples and more detail on this is provided in the Appendix, Troubleshooting: Anatomy of an - Action section. -
-- As mentioned, Privoxy uses "patterns" to determine what actions might apply to - which sites and pages your browser attempts to access. These "patterns" use wild card type pattern matching to - achieve a high degree of flexibility. This allows one expression to - be expanded and potentially match against many similar patterns. -
-- Generally, an URL pattern has the form <domain><port>/<path>, where the - <domain>, the <port> and the <path> are optional. (This is why the special - / pattern matches all URLs). Note that the - protocol portion of the URL pattern (e.g. http://) should not be included in the pattern. This is - assumed already! -
-- The pattern matching syntax is different for the domain and path - parts of the URL. The domain part uses a simple globbing type - matching technique, while the path part uses more flexible "Regular Expressions" (POSIX - 1003.2). -
-- The port part of a pattern is a decimal port number preceded by a - colon (:). If the domain part contains a - numerical IPv6 address, it has to be put into angle brackets (<, >). -
+- is a domain-only pattern and will match any request to www.example.com, regardless of which - document on that server is requested. So ALL pages in this - domain would be covered by the scope of this action. Note - that a simple example.com is - different and would NOT match. -
-- means exactly the same. For domain-only patterns, the - trailing / may be omitted. -
-- matches all the documents on www.example.com whose name starts with /index.html. -
-- matches only the single document /index.html on www.example.com. -
-- matches the document /index.html, - regardless of the domain, i.e. on any web server anywhere. -
-- Matches any URL because there's no requirement for either the - domain or the path to match anything. -
-- Matches any URL pointing to TCP port 8000. -
-- Matches any URL with the host address 2001:db8::1. (Note that the real URL uses - plain brackets, not angle brackets.) -
-- matches nothing, since it would be interpreted as a domain - name and there is no top-level domain called .html. So its a mistake. -
+Modify content using a programming language of your choice.
- The matching of the domain part offers some flexible options: if - the domain starts or ends with a dot, it becomes unanchored at - that end. For example: -
-- matches any domain with first-level domain com and second-level domain example. For example www.example.com, example.com and foo.bar.baz.example.com. Note that it - wouldn't match if the second-level domain was another-example. -
-- matches any domain that STARTS with www. (It also matches the domain www but most of the time that doesn't - matter.) -
-- matches any domain that CONTAINS .example.. And, by the way, also included - would be any files or documents that exist within that - domain since no path limitations are specified. (Correctly - speaking: It matches any FQDN that contains example as a domain.) This might be www.example.com, news.example.de, or www.example.net/cgi/testing.pl for instance. - All these cases are matched. -
-- Additionally, there are wild-cards that you can use in the domain - names themselves. These work similarly to shell globbing type - wild-cards: "*" represents zero or - more arbitrary characters (this is equivalent to the "Regular Expression" based - syntax of ".*"), "?" represents any single character (this is - equivalent to the regular expression syntax of a simple "."), and you can define "character classes" in square brackets which is - similar to the same regular expression technique. All of this can - be freely mixed: -
-- matches "adserver.example.com", - "ads.example.com", etc but not - "sfads.example.com" -
-- matches all of the above, and then some. -
-- matches www.ipix.com, pictures.epix.com, a.b.c.d.e.upix.com etc. -
-- matches www1.example.com, www4.example.cc, wwwd.example.cy, wwwz.example.com etc., but not wwww.example.com. -
-- While flexible, this is not the sophistication of full regular - expression based syntax. -
-- Privoxy uses "modern" POSIX 1003.2 "Regular Expressions" for - matching the path portion (after the slash), and is thus more - flexible. -
-- There is an Appendix with a - brief quick-start into regular expressions, you also might want - to have a look at your operating system's documentation on - regular expressions (try man re_format). -
-- Note that the path pattern is automatically left-anchored at the - "/", i.e. it matches as if it would - start with a "^" (regular expression - speak for the beginning of a line). -
-- Please also note that matching in the path is CASE INSENSITIVE by - default, but you can switch to case sensitive at any point in the - pattern by using the "(?-i)" switch: - www.example.com/(?-i)PaTtErN.* will - match only documents whose path starts with PaTtErN in exactly this capitalization. -
-- Is equivalent to just ".example.com", since any documents within - that domain are matched with or without the ".*" regular expression. This is redundant -
-- Will match any page in the domain of "example.com" that is named "index.html", and that is part of some path. - For example, it matches "www.example.com/testing/index.html" but NOT - "www.example.com/index.html" - because the regular expression called for at least two - "/'s", thus the path - requirement. It also would match "www.example.com/testing/index_html", - because of the special meta-character ".". -
-- This regular expression is conditional so it will match any - page named "index.html" - regardless of path which in this case can have one or more - "/'s". And this one must contain - exactly ".html" (but does not - have to end with that!). -
-- This regular expression will match any path of "example.com" that contains any of the words - "ads", "banner", "banners" (because of the "?") or "junk". - The path does not have to end in these words, just contain - them. -
-- This is very much the same as above, except now it must end - in either ".jpg", ".jpeg", ".gif" - or ".png". So this one is - limited to common image formats. -
-- There are many, many good examples to be found in default.action, and more tutorials below in Appendix on regular expressions. -
-- Tag patterns are used to change the applying actions based on the - request's tags. Tags can be created with either the client-header-tagger - or the server-header-tagger - action. -
-- Tag patterns have to start with "TAG:", so Privoxy can tell them apart from URL - patterns. Everything after the colon including white space, is - interpreted as a regular expression with path pattern syntax, - except that tag patterns aren't left-anchored automatically - (Privoxy doesn't silently add a - "^", you have to do it yourself if you - need it). -
-- To match all requests that are tagged with "foo" your pattern line should be "TAG:^foo$", "TAG:foo" - would work as well, but it would also match requests whose tags - contain "foo" somewhere. "TAG: foo" wouldn't work as it requires white - space. -
-- Sections can contain URL and tag patterns at the same time, but - tag patterns are checked after the URL patterns and thus always - overrule them, even if they are located before the URL patterns. -
-- Once a new tag is added, Privoxy checks right away if it's - matched by one of the tag patterns and updates the action - settings accordingly. As a result tags can be used to activate - other tagger actions, as long as these other taggers look for - headers that haven't already be parsed. -
-- For example you could tag client requests which use the POST method, then use this tag to activate - another tagger that adds a tag if cookies are sent, and then use - a block action based on the cookie tag. This allows the outcome - of one action, to be input into a subsequent action. However if - you'd reverse the position of the described taggers, and - activated the method tagger based on the cookie tagger, no method - tags would be created. The method tagger would look for the - request line, but at the time the cookie tag is created, the - request line has already been parsed. -
-- While this is a limitation you should be aware of, this kind of - indirection is seldom needed anyway and even the example doesn't - make too much sense. -
-- All actions are disabled by default, until they are explicitly - enabled somewhere in an actions file. Actions are turned on if - preceded with a "+", and turned off if - preceded with a "-". So a +action means "do that - action", e.g. +block means "please block URLs that match the following - patterns", and -block means "don't block URLs that match the following patterns, - even if +block previously - applied." -
-- Again, actions are invoked by placing them on a line, enclosed in - curly braces and separated by whitespace, like in {+some-action -some-other-action{some-parameter}}, - followed by a list of URL patterns, one per line, to which they - apply. Together, the actions line and the following pattern lines - make up a section of the actions file. -
-- Actions fall into three categories: -
--
-- Boolean, i.e the action can only be "enabled" or "disabled". Syntax: -
--
-
-- +name # enable action name - -name # disable action name -- |
-
- Example: +handle-as-image -
-- Parameterized, where some value is required in order to enable - this type of action. Syntax: -
--
-
-- +name{param} # enable action and set parameter to param, - # overwriting parameter from previous match if necessary - -name # disable action. The parameter can be omitted -- |
-
- Note that if the URL matches multiple positive forms of a - parameterized action, the last match wins, i.e. the params from - earlier matches are simply ignored. -
-- Example: +hide-user-agent{Mozilla/5.0 (X11; - U; FreeBSD i386; en-US; rv:1.8.1.4) Gecko/20070602 - Firefox/2.0.0.4} -
-- Multi-value. These look exactly like parameterized actions, but - they behave differently: If the action applies multiple times - to the same URL, but with different parameters, all the parameters - from all - matches are remembered. This is used for actions that can be - executed for the same request repeatedly, like adding multiple - headers, or filtering through multiple filters. Syntax: -
--
-
-- +name{param} # enable action and add param to the list of parameters - -name{param} # remove the parameter param from the list of parameters - # If it was the last one left, disable the action. - -name # disable this action completely and remove all parameters from the list -- |
-
- Examples: +add-header{X-Fun-Header: Some - text} and +filter{html-annoyances} -
-- If nothing is specified in any actions file, no "actions" are taken. So in this case Privoxy would just be a normal, non-blocking, - non-filtering proxy. You must specifically enable the privacy and - blocking features you need (although the provided default actions - files will give a good starting point). -
-- Later defined action sections always over-ride earlier ones of the - same type. So exceptions to any rules you make, should come in the - latter part of the file (or in a file that is processed later when - using multiple actions files such as user.action). For multi-valued actions, the actions - are applied in the order they are specified. Actions files are - processed in the order they are defined in config (the default installation has three actions - files). It also quite possible for any given URL to match more than - one "pattern" (because of wildcards and - regular expressions), and thus to trigger more than one set of - actions! Last match wins. -
-- The list of valid Privoxy actions - are: -
-- Confuse log analysis, custom applications -
-- Sends a user defined HTTP header to the web server. -
-- Multi-value. -
-- Any string value is possible. Validity of the defined HTTP - headers is not checked. It is recommended that you use the - "X-" - prefix for custom headers. -
-- This action may be specified multiple times, in order to - define multiple headers. This is rarely needed for the - typical user. If you don't know what "HTTP headers" are, you definitely don't - need to worry about this one. -
-- Headers added by this action are not modified by other - actions. -
--
-
--+add-header{X-User-Tracking: sucks} -- |
-
- Block ads or other unwanted content -
-- Requests for URLs to which this action applies are blocked, - i.e. the requests are trapped by Privoxy and the requested URL is never - retrieved, but is answered locally with a substitute page - or image, as determined by the handle-as-image, - set-image-blocker, - and handle-as-empty-document - actions. -
-- Parameterized. -
-- A block reason that should be given to the user. -
-- Privoxy sends a special - "BLOCKED" page for requests to - blocked pages. This page contains the block reason given as - parameter, a link to find out why the block action applies, - and a click-through to the blocked content (the latter only - if the force feature is available and enabled). -
-- A very important exception occurs if both block and handle-as-image, - apply to the same request: it will then be replaced by an - image. If set-image-blocker - (see below) also applies, the type of image will be - determined by its parameter, if not, the standard - checkerboard pattern is sent. -
-- It is important to understand this process, in order to - understand how Privoxy - deals with ads and other unwanted content. Blocking is a - core feature, and one upon which various other features - depend. -
-- The filter action can - perform a very similar task, by "blocking" banner images and other content - through rewriting the relevant URLs in the document's HTML - source, so they don't get requested in the first place. - Note that this is a totally different technique, and it's - easy to confuse the two. -
--
-
--{+block{No nasty stuff for you.}} -# Block and replace with "blocked" page - .nasty-stuff.example.com - -{+block{Doubleclick banners.} +handle-as-image} -# Block and replace with image - .ad.doubleclick.net - .ads.r.us/banners/ - -{+block{Layered ads.} +handle-as-empty-document} -# Block and then ignore - adserver.example.net/.*\.js$ -- |
-
- Improve privacy by not forwarding the source of the request - in the HTTP headers. -
-- Deletes the "X-Forwarded-For:" - HTTP header from the client request, or adds a new one. -
-- Parameterized. -
-- "block" to delete the - header. -
-- "add" to create the header - (or append the client's IP address to an already - existing one). -
-- It is safe and recommended to use block. -
-- Forwarding the source address of the request may make sense - in some multi-user setups but is also a privacy risk. -
--
-
--+change-x-forwarded-for{block} -- |
-
- Rewrite or remove single client headers. -
-- All client headers to which this action applies are - filtered on-the-fly through the specified regular - expression based substitutions. -
-- Parameterized. -
-- The name of a client-header filter, as defined in one of - the filter files. -
-- Client-header filters are applied to each header on its - own, not to all at once. This makes it easier to diagnose - problems, but on the downside you can't write filters that - only change header x if header y's value is z. You can do - that by using tags though. -
-- Client-header filters are executed after the other header - actions have finished and use their output as input. -
-- If the request URL gets changed, Privoxy will detect that and use the - new one. This can be used to rewrite the request - destination behind the client's back, for example to - specify a Tor exit relay for certain requests. -
-- Please refer to the filter file - chapter to learn which client-header filters are - available by default, and how to create your own. -
--
-
--# Hide Tor exit notation in Host and Referer Headers -{+client-header-filter{hide-tor-exit-notation}} -/ - -- |
-
- Block requests based on their headers. -
-- Client headers to which this action applies are filtered - on-the-fly through the specified regular expression based - substitutions, the result is used as tag. -
-- Parameterized. -
-- The name of a client-header tagger, as defined in one of - the filter files. -
-- Client-header taggers are applied to each header on its - own, and as the header isn't modified, each tagger "sees" the original. -
-- Client-header taggers are the first actions that are - executed and their tags can be used to control every other - action. -
--
-
--# Tag every request with the User-Agent header -{+client-header-tagger{user-agent}} -/ - -# Tagging itself doesn't change the action -# settings, sections with TAG patterns do: -# -# If it's a download agent, use a different forwarding proxy, -# show the real User-Agent and make sure resume works. -{+forward-override{forward-socks5 10.0.0.2:2222 .} \ - -hide-if-modified-since \ - -overwrite-last-modified \ - -hide-user-agent \ - -filter \ - -deanimate-gifs \ -} -TAG:^User-Agent: NetBSD-ftp/ -TAG:^User-Agent: Novell ZYPP Installer -TAG:^User-Agent: RPM APT-HTTP/ -TAG:^User-Agent: fetch libfetch/ -TAG:^User-Agent: Ubuntu APT-HTTP/ -TAG:^User-Agent: MPlayer/ - -- |
-
- Stop useless download menus from popping up, or change the - browser's rendering mode -
-- Replaces the "Content-Type:" - HTTP server header. -
-- Parameterized. -
-- Any string. -
-- The "Content-Type:" HTTP server - header is used by the browser to decide what to do with the - document. The value of this header can cause the browser to - open a download menu instead of displaying the document by - itself, even if the document's format is supported by the - browser. -
-- The declared content type can also affect which rendering - mode the browser chooses. If XHTML is delivered as "text/html", many browsers treat it as - yet another broken HTML document. If it is send as "application/xml", browsers with XHTML - support will only display it, if the syntax is correct. -
-- If you see a web site that proudly uses XHTML buttons, but - sets "Content-Type: text/html", - you can use Privoxy to - overwrite it with "application/xml" and validate the web - master's claim inside your XHTML-supporting browser. If the - syntax is incorrect, the browser will complain loudly. -
-- You can also go the opposite direction: if your browser - prints error messages instead of rendering a document - falsely declared as XHTML, you can overwrite the content - type with "text/html" and have - it rendered as broken HTML document. -
-- By default content-type-overwrite - only replaces "Content-Type:" - headers that look like some kind of text. If you want to - overwrite it unconditionally, you have to combine it with - force-text-mode. - This limitation exists for a reason, think twice before - circumventing it. -
-- Most of the time it's easier to replace this action with a - custom server-header - filter. It allows you to activate it for every - document of a certain site and it will still only replace - the content types you aimed at. -
-- Of course you can apply content-type-overwrite to a whole site and - then make URL based exceptions, but it's a lot more work to - get the same precision. -
--
-
--# Check if www.example.net/ really uses valid XHTML -{ +content-type-overwrite{application/xml} } -www.example.net/ - -# but leave the content type unmodified if the URL looks like a style sheet -{-content-type-overwrite} -www.example.net/.*\.css$ -www.example.net/.*style -- |
-
- Remove a client header Privoxy has no dedicated action for. -
-- Deletes every header sent by the client that contains the - string the user supplied as parameter. -
-- Parameterized. -
-- Any string. -
-- This action allows you to block client headers for which no - dedicated Privoxy action - exists. Privoxy will - remove every client header that contains the string you - supplied as parameter. -
-- Regular expressions are not supported and you can't use this - action to block different headers in the same request, - unless they contain the same string. -
-- crunch-client-header is only meant - for quick tests. If you have to block several different - headers, or only want to modify parts of them, you should - use a client-header - filter. -
-- Warning - | -
- - Don't block any header without understanding the - consequences. - - |
-
-
-
--# Block the non-existent "Privacy-Violation:" client header -{ +crunch-client-header{Privacy-Violation:} } -/ - -- |
-
- Prevent yet another way to track the user's steps between - sessions. -
-- Deletes the "If-None-Match:" - HTTP client header. -
-- Boolean. -
-- N/A -
-- Removing the "If-None-Match:" - HTTP client header is useful for filter testing, where you - want to force a real reload instead of getting status code - "304" which would cause the - browser to use a cached copy of the page. -
-- It is also useful to make sure the header isn't used as a - cookie replacement (unlikely but possible). -
-- Blocking the "If-None-Match:" - header shouldn't cause any caching problems, as long as the - "If-Modified-Since:" header - isn't blocked or missing as well. -
-- It is recommended to use this action together with hide-if-modified-since - and overwrite-last-modified. -
--
-
--# Let the browser revalidate cached documents but don't -# allow the server to use the revalidation headers for user tracking. -{+hide-if-modified-since{-60} \ - +overwrite-last-modified{randomize} \ - +crunch-if-none-match} -/ -- |
-
- Prevent the web server from setting HTTP cookies on your - system -
-- Deletes any "Set-Cookie:" HTTP - headers from server replies. -
-- Boolean. -
-- N/A -
-- This action is only concerned with incoming HTTP - cookies. For outgoing HTTP cookies, use crunch-outgoing-cookies. - Use both to disable HTTP cookies - completely. -
-- It makes no - sense at all to use this action in conjunction - with the session-cookies-only - action, since it would prevent the session cookies from - being set. See also filter-content-cookies. -
--
-
--+crunch-incoming-cookies -- |
-
- Remove a server header Privoxy has no dedicated action for. -
-- Deletes every header sent by the server that contains the - string the user supplied as parameter. -
-- Parameterized. -
-- Any string. -
-- This action allows you to block server headers for which no - dedicated Privoxy action - exists. Privoxy will - remove every server header that contains the string you - supplied as parameter. -
-- Regular expressions are not supported and you can't use this - action to block different headers in the same request, - unless they contain the same string. -
-- crunch-server-header is only meant - for quick tests. If you have to block several different - headers, or only want to modify parts of them, you should - use a custom server-header - filter. -
-- Warning - | -
- - Don't block any header without understanding the - consequences. - - |
-
-
-
--# Crunch server headers that try to prevent caching -{ +crunch-server-header{no-cache} } -/ -- |
-
- Prevent the web server from reading any HTTP cookies from - your system -
-- Deletes any "Cookie:" HTTP - headers from client requests. -
-- Boolean. -
-- N/A -
-- This action is only concerned with outgoing HTTP - cookies. For incoming HTTP cookies, use crunch-incoming-cookies. - Use both to disable HTTP cookies - completely. -
-- It makes no - sense at all to use this action in conjunction - with the session-cookies-only - action, since it would prevent the session cookies from - being read. -
--
-
--+crunch-outgoing-cookies -- |
-
- Stop those annoying, distracting animated GIF images. -
-- De-animate GIF animations, i.e. reduce them to their first - or last image. -
-- Parameterized. -
-- "last" or "first" -
-- This will also shrink the images considerably (in bytes, - not pixels!). If the option "first" is given, the first frame of the - animation is used as the replacement. If "last" is given, the last frame of the - animation is used instead, which probably makes more sense - for most banner animations, but also has the risk of not - showing the entire last frame (if it is only a delta to an - earlier frame). -
-- You can safely use this action with patterns that will also - match non-GIF objects, because no attempt will be made at - anything that doesn't look like a GIF. -
--
-
--+deanimate-gifs{last} -- |
+ Warning |
- Work around (very rare) problems with HTTP/1.1 -
-- Downgrades HTTP/1.1 client requests and server replies to - HTTP/1.0. -
-- Boolean. -
-- N/A -
-- This is a left-over from the time when Privoxy didn't support important - HTTP/1.1 features well. It is left here for the unlikely - case that you experience HTTP/1.1 related problems with - some server out there. Not all HTTP/1.1 features and - requirements are supported yet, so there is a chance you - might need this action. -
--
-
--{+downgrade-http-version} -problem-host.example.com -+ |
+ Currently external filters are executed with Privoxy's + privileges. Only use external filters you understand and trust. |
This feature is experimental, the syntax may change in the future.
+
+ +external-filter{fancy-filter}+ |
+
- Fool some click-tracking scripts and speed up indirect - links. -
-- Detects redirection URLs and redirects the browser without - contacting the redirection server first. -
-- Parameterized. -
-- "simple-check" to just - search for the string "http://" to detect redirection URLs. -
-- "check-decoded-url" to - decode URLs (if necessary) before searching for - redirection URLs. -
-- Many sites, like yahoo.com, don't just link to other sites. - Instead, they will link to some script on their own - servers, giving the destination as a parameter, which will - then redirect you to the final target. URLs resulting from - this scheme typically look like: "http://www.example.org/click-tracker.cgi?target=http%3a//www.example.net/". -
-- Sometimes, there are even multiple consecutive redirects - encoded in the URL. These redirections via scripts make - your web browsing more traceable, since the server from - which you follow such a link can see where you go to. Apart - from that, valuable bandwidth and time is wasted, while - your browser asks the server for one redirect after the - other. Plus, it feeds the advertisers. -
-- This feature is currently not very smart and is scheduled - for improvement. If it is enabled by default, you will have - to create some exceptions to this action. It can lead to - failures in several ways: -
-- Not every URLs with other URLs as parameters is evil. Some - sites offer a real service that requires this information - to work. For example a validation service needs to know, - which document to validate. fast-redirects assumes that every URL - parameter that looks like another URL is a redirection - target, and will always redirect to the last one. Most of - the time the assumption is correct, but if it isn't, the - user gets redirected anyway. -
-- Another failure occurs if the URL contains other parameters - after the URL parameter. The URL: "http://www.example.org/?redirect=http%3a//www.example.net/&foo=bar". - contains the redirection URL "http://www.example.net/", followed by - another parameter. fast-redirects - doesn't know that and will cause a redirect to "http://www.example.net/&foo=bar". - Depending on the target server configuration, the parameter - will be silently ignored or lead to a "page not found" error. You can prevent this - problem by first using the redirect action to - remove the last part of the URL, but it requires a little - effort. -
-- To detect a redirection URL, fast-redirects only looks for the string - "http://", either in plain text - (invalid but often used) or encoded as "http%3a//". Some sites use their own URL - encoding scheme, encrypt the address of the target server - or replace it with a database id. In theses cases fast-redirects is fooled and the - request reaches the redirection server where it probably - gets logged. -
--
-
-- { +fast-redirects{simple-check} } + + |
+
- Get rid of HTML and JavaScript annoyances, banner - advertisements (by size), do fun text replacements, add - personalized effects, etc. -
-- All instances of text-based type, most notably HTML and - JavaScript, to which this action applies, can be filtered - on-the-fly through the specified regular expression based - substitutions. (Note: as of version 3.0.3 plain text - documents are exempted from filtering, because web servers - often use the text/plain MIME type - for all files whose type they don't know.) -
-- Parameterized. -
-- The name of a content filter, as defined in the filter file. Filters can be defined - in one or more files as defined by the filterfile option in the - config file. default.filter is the collection of filters - supplied by the developers. Locally defined filters should - go in their own file, such as user.filter. -
-- When used in its negative form, and without parameters, - all - filtering is completely disabled. -
-- For your convenience, there are a number of pre-defined - filters available in the distribution filter file that you - can use. See the examples below for a list. -
-- Filtering requires buffering the page content, which may - appear to slow down page rendering since nothing is - displayed until all content has passed the filters. (The - total time until the page is completely rendered doesn't - change much, but it may be perceived as slower since the - page is not incrementally displayed.) This effect will be - more noticeable on slower connections. -
-- "Rolling your own" filters - requires a knowledge of "Regular Expressions" - and "HTML". This is very - powerful feature, and potentially very intrusive. Filters - should be used with caution, and where an equivalent "action" is not available. -
-- The amount of data that can be filtered is limited to the - buffer-limit option in - the main config file. The default - is 4096 KB (4 Megs). Once this limit is exceeded, the - buffered data, and all pending data, is passed through - unfiltered. -
-- Inappropriate MIME types, such as zipped files, are not - filtered at all. (Again, only text-based types except plain - text). Encrypted SSL data (from HTTPS servers) cannot be - filtered either, since this would violate the integrity of - the secure transaction. In some situations it might be - necessary to protect certain text, like source code, from - filtering by defining appropriate -filter exceptions. -
-- Compressed content can't be filtered either, unless Privoxy is compiled with zlib - support (requires at least Privoxy 3.0.7), in which case Privoxy will decompress the - content before filtering it. -
-- If you use a Privoxy - version without zlib support, but want filtering to work on - as much documents as possible, even those that would - normally be sent compressed, you must use the prevent-compression - action in conjunction with filter. -
-- Content filtering can achieve some of the same effects as - the block action, i.e. it - can be used to block ads and banners. But the mechanism - works quite differently. One effective use, is to block ad - banners based on their size (see below), since many of - these seem to be somewhat standardized. -
-- Feedback with suggestions for - new or improved filters is particularly welcome! -
-- The below list has only the names and a one-line - description of each predefined filter. There are more verbose - explanations of what these filters do in the filter file chapter. -
-
--+filter{js-annoyances} # Get rid of particularly annoying JavaScript abuse. -- |
-
--+filter{js-events} # Kill all JS event bindings and timers (Radically destructive! Only for extra nasty sites). -- |
-
--+filter{html-annoyances} # Get rid of particularly annoying HTML abuse. -- |
-
--+filter{content-cookies} # Kill cookies that come in the HTML or JS content. -- |
-
--+filter{refresh-tags} # Kill automatic refresh tags (for dial-on-demand setups). -- |
-
--+filter{unsolicited-popups} # Disable only unsolicited pop-up windows. Useful if your browser lacks this ability. -- |
-
--+filter{all-popups} # Kill all popups in JavaScript and HTML. Useful if your browser lacks this ability. -- |
-
--+filter{img-reorder} # Reorder attributes in <img> tags to make the banners-by-* filters more effective. -- |
-
--+filter{banners-by-size} # Kill banners by size. -- |
-
--+filter{banners-by-link} # Kill banners by their links to known clicktrackers. -- |
-
--+filter{webbugs} # Squish WebBugs (1x1 invisible GIFs used for user tracking). -- |
-
--+filter{tiny-textforms} # Extend those tiny textareas up to 40x80 and kill the hard wrap. -- |
-
--+filter{jumping-windows} # Prevent windows from resizing and moving themselves. -- |
-
--+filter{frameset-borders} # Give frames a border and make them resizable. -- |
-
--+filter{demoronizer} # Fix MS's non-standard use of standard charsets. -- |
-
--+filter{shockwave-flash} # Kill embedded Shockwave Flash objects. -- |
-
--+filter{quicktime-kioskmode} # Make Quicktime movies saveable. -- |
-
--+filter{fun} # Text replacements for subversive browsing fun! -- |
-
--+filter{crude-parental} # Crude parental filtering. Note that this filter doesn't work reliably. -- |
-
--+filter{ie-exploits} # Disable some known Internet Explorer bug exploits. -- |
-
--+filter{site-specifics} # Cure for site-specific problems. Don't apply generally! -- |
-
--+filter{no-ping} # Removes non-standard ping attributes in <a> and <area> tags. -- |
-
--+filter{google} # CSS-based block for Google text ads. Also removes a width limitation and the toolbar advertisement. -- |
-
+ +filter{js-annoyances} # Get rid of particularly annoying JavaScript abuse.+ |
+
+ +filter{js-events} # Kill JavaScript event bindings and timers (Radically destructive! Only for extra nasty sites).+ |
+
+ +filter{html-annoyances} # Get rid of particularly annoying HTML abuse.+ |
+
+ +filter{content-cookies} # Kill cookies that come in the HTML or JS content.+ |
+
+ +filter{refresh-tags} # Kill automatic refresh tags if refresh time is larger than 9 seconds.+ |
+
+ +filter{unsolicited-popups} # Disable only unsolicited pop-up windows.+ |
+
+ +filter{all-popups} # Kill all popups in JavaScript and HTML.+ |
+
+ +filter{img-reorder} # Reorder attributes in <img> tags to make the banners-by-* filters more effective.+ |
+
+ +filter{banners-by-size} # Kill banners by size.+ |
+
+ +filter{banners-by-link} # Kill banners by their links to known clicktrackers.+ |
+
+ +filter{webbugs} # Squish WebBugs (1x1 invisible GIFs used for user tracking).+ |
+
+ +filter{tiny-textforms} # Extend those tiny textareas up to 40x80 and kill the hard wrap.+ |
+
+ +filter{jumping-windows} # Prevent windows from resizing and moving themselves.+ |
+
+ +filter{frameset-borders} # Give frames a border and make them resizable.+ |
+
+ +filter{iframes} # Removes all detected iframes. Should only be enabled for individual sites.+ |
+
+ +filter{demoronizer} # Fix MS's non-standard use of standard charsets.+ |
+
+ +filter{shockwave-flash} # Kill embedded Shockwave Flash objects.+ |
+
+ +filter{quicktime-kioskmode} # Make Quicktime movies saveable.+ |
+
+ +filter{fun} # Text replacements for subversive browsing fun!+ |
+
+ +filter{crude-parental} # Crude parental filtering. Note that this filter doesn't work reliably.+ |
+
+ +filter{ie-exploits} # Disable some known Internet Explorer bug exploits.+ |
+
+ +filter{site-specifics} # Cure for site-specific problems. Don't apply generally!+ |
+
+ +filter{no-ping} # Removes non-standard ping attributes in <a> and <area> tags.+ |
+
+ +filter{google} # CSS-based block for Google text ads. Also removes a width limitation and the toolbar advertisement.+ |
+
+ +filter{yahoo} # CSS-based block for Yahoo text ads. Also removes a width limitation.+ |
+
+ +filter{msn} # CSS-based block for MSN text ads. Also removes tracking URLs and a width limitation.+ |
+
+ +filter{blogspot} # Cleans up some Blogspot blogs. Read the fine print before using this.+ |
+
Force Privoxy to treat a document as if it was in some kind of + text format.
+Declares a document as text, even if the "Content-Type:" isn't detected as + such.
+Boolean.
+N/A
+As explained above, Privoxy tries to only filter files that are in some kind of text format. The same + restrictions apply to content-type-overwrite. force-text-mode declares a document as text, without looking at the "Content-Type:" first.
+
--+filter{yahoo} # CSS-based block for Yahoo text ads. Also removes a width limitation. -- |
+ Warning |
--+filter{msn} # CSS-based block for MSN text ads. Also removes tracking URLs and a width limitation. -+ |
+ Think twice before activating this action. Filtering binary data with regular expressions can + cause file damage. |
+ +force-text-mode+ |
+
Change the forwarding settings based on User-Agent or request origin
+Overrules the forward directives in the configuration file.
+Parameterized.
+"forward ." to use a direct connection without any additional + proxies.
+"forward 127.0.0.1:8123" to use the HTTP proxy listening at 127.0.0.1 + port 8123.
+"forward-socks4a 127.0.0.1:9050 ." to use the socks4a proxy listening + at 127.0.0.1 port 9050. Replace "forward-socks4a" with "forward-socks4" to use a socks4 connection (with local DNS resolution) instead, use + "forward-socks5" for socks5 connections (with remote DNS resolution).
+"forward-socks4a 127.0.0.1:9050 proxy.example.org:8000" to use the + socks4a proxy listening at 127.0.0.1 port 9050 to reach the HTTP proxy listening at proxy.example.org + port 8000. Replace "forward-socks4a" with "forward-socks4" to use a socks4 connection (with local DNS resolution) instead, use + "forward-socks5" for socks5 connections (with remote DNS resolution).
+"forward-webserver 127.0.0.1:80" to use the HTTP server listening at + 127.0.0.1 port 80 without adjusting the request headers.
+This makes it more convenient to use Privoxy to make existing websites available as onion services + as well.
+Many websites serve content with hardcoded URLs and can't be easily adjusted to change the domain + based on the one used by the client.
+Putting Privoxy between Tor and the webserver (or an stunnel that forwards to the webserver) + allows to rewrite headers and content to make client and server happy at the same time.
+Using Privoxy for webservers that are only reachable through onion addresses and whose location is + supposed to be secret is not recommended and should not be necessary anyway.
+This action takes parameters similar to the forward directives in + the configuration file, but without the URL pattern. It can be used as replacement, but normally it's + only used in cases where matching based on the request URL isn't sufficient.
+
--+filter{blogspot} # Cleans up some Blogspot blogs. Read the fine print before using this. -- |
+ Warning |
- Force Privoxy to treat a - document as if it was in some kind of text format. -
-- Declares a document as text, even if the "Content-Type:" isn't detected as such. -
-- Boolean. -
-- N/A -
-- As explained above, Privoxy tries to only filter files - that are in some kind of text format. The same restrictions - apply to content-type-overwrite. - force-text-mode declares a - document as text, without looking at the "Content-Type:" first. -
-- Warning - | -
- - Think twice before activating this action. - Filtering binary data with regular expressions can - cause file damage. - - |
-
-
-
--+force-text-mode - -+ |
+ Please read the description for the forward directives + before using this action. Forwarding to the wrong people will reduce your privacy and increase + the chances of man-in-the-middle attacks. +If the ports are missing or invalid, default values will be used. This might change in the + future and you shouldn't rely on it. Otherwise incorrect syntax causes Privoxy to exit. Due to + design limitations, invalid parameter syntax isn't detected until the action is used the first + time. +Use the show-url-info CGI + page to verify that your forward settings do what you thought the do. |
- Change the forwarding settings based on User-Agent or - request origin -
-- Overrules the forward directives in the configuration file. -
-- Multi-value. -
-- "forward ." to use a direct - connection without any additional proxies. -
-- "forward 127.0.0.1:8123" to - use the HTTP proxy listening at 127.0.0.1 port 8123. -
-- "forward-socks4a 127.0.0.1:9050 - ." to use the socks4a proxy listening at - 127.0.0.1 port 9050. Replace "forward-socks4a" with "forward-socks4" to use a socks4 - connection (with local DNS resolution) instead, use - "forward-socks5" for socks5 - connections (with remote DNS resolution). -
-- "forward-socks4a 127.0.0.1:9050 - proxy.example.org:8000" to use the socks4a proxy - listening at 127.0.0.1 port 9050 to reach the HTTP - proxy listening at proxy.example.org port 8000. Replace - "forward-socks4a" with "forward-socks4" to use a socks4 - connection (with local DNS resolution) instead, use - "forward-socks5" for socks5 - connections (with remote DNS resolution). -
-- This action takes parameters similar to the forward directives in the - configuration file, but without the URL pattern. It can be - used as replacement, but normally it's only used in cases - where matching based on the request URL isn't sufficient. -
-- Warning - | -
- - Please read the description for the forward directives - before using this action. Forwarding to the wrong - people will reduce your privacy and increase the - chances of man-in-the-middle attacks. - -- If the ports are missing or invalid, default values - will be used. This might change in the future and - you shouldn't rely on it. Otherwise incorrect - syntax causes Privoxy to exit. - -- Use the show-url-info CGI page to verify that - your forward settings do what you thought the do. - - |
-
-
-
--# Always use direct connections for requests previously tagged as + + +
|
+
- Mark URLs that should be replaced by empty documents if they get - blocked -
-- This action alone doesn't do anything noticeable. It just - marks URLs. If the block action also - applies, the presence or absence of this mark - decides whether an HTML "BLOCKED" page, or an empty document will be - sent to the client as a substitute for the blocked content. - The empty document isn't literally empty, - but actually contains a single space. -
-- Boolean. -
-- N/A -
-- Some browsers complain about syntax errors if JavaScript - documents are blocked with Privoxy's default HTML page; this - option can be used to silence them. And of course this - action can also be used to eliminate the Privoxy BLOCKED message in frames. -
-- The content type for the empty document can be specified - with content-type-overwrite{}, - but usually this isn't necessary. -
--
-
--# Block all documents on example.org that end with ".js", + + |
+
- Mark URLs as belonging to images (so they'll be replaced by - images if they - do get blocked, rather than HTML pages) -
-- This action alone doesn't do anything noticeable. It just - marks URLs as images. If the block action also - applies, the presence or absence of this mark - decides whether an HTML "blocked" page, or a replacement image (as - determined by the set-image-blocker - action) will be sent to the client as a substitute for the - blocked content. -
-- Boolean. -
-- N/A -
-- The below generic example section is actually part of default.action. It marks all URLs - with well-known image file name extensions as images and - should be left intact. -
-- Users will probably only want to use the handle-as-image - action in conjunction with block, to block sources - of banners, whose URLs don't reflect the file type, like in - the second example section. -
-- Note that you cannot treat HTML pages as images in most - cases. For instance, (in-line) ad frames require an HTML - page to be sent, or they won't display properly. Forcing - handle-as-image in this situation - will not replace the ad frame with an image, but lead to - error messages. -
--
-
--# Generic image extensions: + + |
+
- Pretend to use different language settings. -
-- Deletes or replaces the "Accept-Language:" HTTP header in client - requests. -
-- Parameterized. -
-- Keyword: "block", or any user - defined value. -
-- Faking the browser's language settings can be useful to - make a foreign User-Agent set with hide-user-agent - more believable. -
-- However some sites with content in different languages - check the "Accept-Language:" to - decide which one to take by default. Sometimes it isn't - possible to later switch to another language without - changing the "Accept-Language:" - header first. -
-- Therefore it's a good idea to either only change the "Accept-Language:" header to languages - you understand, or to languages that aren't wide spread. -
-- Before setting the "Accept-Language:" header to a rare - language, you should consider that it helps to make your - requests unique and thus easier to trace. If you don't plan - to change this header frequently, you should stick to a - common language. -
--
-
--# Pretend to use Canadian language settings. + + |
+
- Prevent download menus for content you prefer to view - inside the browser. -
-- Deletes or replaces the "Content-Disposition:" HTTP header set by - some servers. -
-- Parameterized. -
-- Keyword: "block", or any user - defined value. -
-- Some servers set the "Content-Disposition:" HTTP header for - documents they assume you want to save locally before - viewing them. The "Content-Disposition:" header contains the - file name the browser is supposed to use by default. -
-- In most browsers that understand this header, it makes it - impossible to just view the document, without - downloading it first, even if it's just a simple text file - or an image. -
-- Removing the "Content-Disposition:" header helps to - prevent this annoyance, but some browsers additionally - check the "Content-Type:" - header, before they decide if they can display a document - without saving it first. In these cases, you have to change - this header as well, before the browser stops displaying - download menus. -
-- It is also possible to change the server's file name - suggestion to another one, but in most cases it isn't worth - the time to set it up. -
-- This action will probably be removed in the future, use - server-header filters instead. -
--
-
--# Disarm the download link in Sourceforge's patch tracker + + |
+
- Prevent yet another way to track the user's steps between - sessions. -
-- Deletes the "If-Modified-Since:" - HTTP client header or modifies its value. -
-- Parameterized. -
-- Keyword: "block", or a user - defined value that specifies a range of hours. -
-- Removing this header is useful for filter testing, where - you want to force a real reload instead of getting status - code "304", which would cause - the browser to use a cached copy of the page. -
-- Instead of removing the header, hide-if-modified-since can also add or - subtract a random amount of time to/from the header's - value. You specify a range of minutes where the random - factor should be chosen from and Privoxy does the rest. A negative - value means subtracting, a positive value adding. -
-- Randomizing the value of the "If-Modified-Since:" makes it less likely - that the server can use the time as a cookie replacement, - but you will run into caching problems if the random range - is too high. -
-- It is a good idea to only use a small negative value and - let overwrite-last-modified - handle the greater changes. -
-- It is also recommended to use this action together with crunch-if-none-match, - otherwise it's more or less pointless. -
--
-
--# Let the browser revalidate but make tracking based on the time less likely. + + |
+
- Keep your (old and ill) browser from telling web servers - your email address -
-- Deletes any existing "From:" - HTTP header, or replaces it with the specified string. -
-- Parameterized. -
-- Keyword: "block", or any user - defined value. -
-- The keyword "block" will - completely remove the header (not to be confused with the - block action). -
-- Alternately, you can specify any value you prefer to be - sent to the web server. If you do, it is a matter of - fairness not to use any address that is actually used by a - real person. -
-- This action is rarely needed, as modern web browsers don't - send "From:" headers anymore. -
--
-
--+hide-from-header{block} -- |
-
--+hide-from-header{spam-me-senseless@sittingduck.example.com} -- |
-
Keep your (old and ill) browser from telling web servers your email address
+Deletes any existing "From:" HTTP header, or replaces it with the specified + string.
+Parameterized.
+Keyword: "block", or any user defined value.
+The keyword "block" will completely remove the header (not to be confused + with the block action).
+Alternately, you can specify any value you prefer to be sent to the web server. If you do, it is a + matter of fairness not to use any address that is actually used by a real person.
+This action is rarely needed, as modern web browsers don't send "From:" + headers anymore.
+
+ +hide-from-header{block}+ |
+
or
+
+ +hide-from-header{spam-me-senseless@sittingduck.example.com}+ |
+
Conceal which link you followed to get to a particular site
+Deletes the "Referer:" (sic) HTTP header from the client request, or + replaces it with a forged one.
+Parameterized.
+"conditional-block" to delete the header completely if the host has + changed.
+"conditional-forge" to forge the header if the host has changed.
+"block" to delete the header unconditionally.
+"forge" to pretend to be coming from the homepage of the server we are + talking to.
+Any other string to set a user defined referrer.
+conditional-block is the only parameter, that isn't easily detected in the + server's log file. If it blocks the referrer, the request will look like the visitor used a bookmark or + typed in the address directly.
+Leaving the referrer unmodified for requests on the same host allows the server owner to see the + visitor's "click path", but in most cases she could also get that information + by comparing other parts of the log file: for example the User-Agent if it isn't a very common one, or + the user's IP address if it doesn't change between different requests.
+Always blocking the referrer, or using a custom one, can lead to failures on servers that check the + referrer before they answer any requests, in an attempt to prevent their content from being embedded or + linked to elsewhere.
+Both conditional-block and forge will work with + referrer checks, as long as content and valid referring page are on the same host. Most of the time + that's the case.
+hide-referer is an alternate spelling of hide-referrer and the two can be can be freely substituted with each other. ("referrer" is the correct English spelling, however the HTTP specification has a bug - it + requires it to be spelled as "referer".)
+
+ +hide-referrer{forge}+ |
+
or
+
+ +hide-referrer{http://www.yahoo.com/}+ |
+
- Conceal which link you followed to get to a particular site -
-- Deletes the "Referer:" (sic) - HTTP header from the client request, or replaces it with a - forged one. -
-- Parameterized. -
-- "conditional-block" to - delete the header completely if the host has changed. -
-- "conditional-forge" to forge - the header if the host has changed. -
-- "block" to delete the header - unconditionally. -
-- "forge" to pretend to be - coming from the homepage of the server we are talking - to. -
-- Any other string to set a user defined referrer. -
-- conditional-block is the only - parameter, that isn't easily detected in the server's log - file. If it blocks the referrer, the request will look like - the visitor used a bookmark or typed in the address - directly. -
-- Leaving the referrer unmodified for requests on the same - host allows the server owner to see the visitor's "click path", but in most cases she - could also get that information by comparing other parts of - the log file: for example the User-Agent if it isn't a very - common one, or the user's IP address if it doesn't change - between different requests. -
-- Always blocking the referrer, or using a custom one, can - lead to failures on servers that check the referrer before - they answer any requests, in an attempt to prevent their - content from being embedded or linked to elsewhere. -
-- Both conditional-block and forge will work with referrer checks, - as long as content and valid referring page are on the same - host. Most of the time that's the case. -
-- hide-referer is an alternate - spelling of hide-referrer and the - two can be can be freely substituted with each other. - ("referrer" is the correct - English spelling, however the HTTP specification has a bug - - it requires it to be spelled as "referer".) -
--
-
--+hide-referrer{forge} -- |
+ Warning |
--+hide-referrer{http://www.yahoo.com/} -+ |
+ This can lead to problems on web sites that depend on looking at this header in order to + customize their content for different browsers (which, by the way, is NOT the right thing to do: good web sites work + browser-independently). |
Using this action in multi-user setups or wherever different types of browsers will access the same + Privoxy is not + recommended. In single-user, single-browser setups, you might use it to delete your OS version + information from the headers, because it is an invitation to exploit known bugs for your OS. It is also + occasionally useful to forge this in order to access sites that won't let you in otherwise (though there + may be a good reason in some cases).
+More information on known user-agent strings can be found at http://www.user-agents.org/ and http://en.wikipedia.org/wiki/User_agent.
+ +
+ +hide-user-agent{Netscape 6.1 (X11; I; Linux 2.4.18 i686)}+ |
+
- Try to conceal your type of browser and client operating - system -
-- Replaces the value of the "User-Agent:" HTTP header in client requests - with the specified value. -
-- Parameterized. -
-- Any user-defined string. -
-- Warning - | -
- - This can lead to problems on web sites that depend - on looking at this header in order to customize - their content for different browsers (which, by the - way, is NOT the right thing to do: - good web sites work browser-independently). - - |
-
- Using this action in multi-user setups or wherever - different types of browsers will access the same Privoxy is not recommended. - In single-user, single-browser setups, you might use it to - delete your OS version information from the headers, - because it is an invitation to exploit known bugs for your - OS. It is also occasionally useful to forge this in order - to access sites that won't let you in otherwise (though - there may be a good reason in some cases). -
-- More information on known user-agent strings can be found - at http://www.user-agents.org/ and http://en.wikipedia.org/wiki/User_agent. -
--
-
--+hide-user-agent{Netscape 6.1 (X11; I; Linux 2.4.18 i686)} -- |
-
Filter encrypted requests and responses
+Encrypted requests are decrypted, filtered and forwarded encrypted.
+Boolean.
+N/A
+This action allows Privoxy to filter encrypted requests and + responses. For this to work Privoxy has to generate a certificate and + send it to the client which has to accept it.
+Before this works the directives in the TLS section of the config file have to be configured.
+Note that the action has to be enabled based on the CONNECT request which doesn't contain a path. + Enabling it based on a pattern with path doesn't work as the path is only seen by Privoxy if the action is already enabled.
+
+ {+https-inspection} +www.example.com+ |
+
- Prevent abuse of Privoxy - as a TCP proxy relay or disable SSL for untrusted sites -
-- Specifies to which ports HTTP CONNECT requests are - allowable. -
-- Parameterized. -
-- A comma-separated list of ports or port ranges (the latter - using dashes, with the minimum defaulting to 0 and the - maximum to 65K). -
-- By default, i.e. if no limit-connect action applies, Privoxy allows HTTP CONNECT requests - to all ports. Use limit-connect if - fine-grained control is desired for some or all - destinations. -
-- The CONNECT methods exists in HTTP to allow access to - secure websites ("https://" - URLs) through proxies. It works very simply: the proxy - connects to the server on the specified port, and then - short-circuits its connections to the client and to the - remote server. This means CONNECT-enabled proxies can be - used as TCP relays very easily. -
-- Privoxy relays HTTPS - traffic without seeing the decoded content. Websites can - leverage this limitation to circumvent Privoxy's filters. By specifying an - invalid port range you can disable HTTPS entirely. -
--
-
--+limit-connect{443} # Port 443 is OK. + + |
+
- Ensure that servers send the content uncompressed, so it - can be passed through filters. -
-- Removes the Accept-Encoding header which can be used to ask - for compressed transfer. -
-- Boolean. -
-- N/A -
-- More and more websites send their content compressed by - default, which is generally a good idea and saves - bandwidth. But the filter and deanimate-gifs - actions need access to the uncompressed data. -
-- When compiled with zlib support (available since Privoxy 3.0.7), content that - should be filtered is decompressed on-the-fly and you don't - have to worry about this action. If you are using an older - Privoxy version, or one - that hasn't been compiled with zlib support, this action - can be used to convince the server to send the content - uncompressed. -
-- Most text-based instances compress very well, the size is - seldom decreased by less than 50%, for markup-heavy - instances like news feeds saving more than 90% of the - original size isn't unusual. -
-- Not using compression will therefore slow down the - transfer, and you should only enable this action if you - really need it. As of Privoxy 3.0.7 it's disabled in all - predefined action settings. -
-- Note that some (rare) ill-configured sites don't handle - requests for uncompressed documents correctly. Broken PHP - applications tend to send an empty document body, some IIS - versions only send the beginning of the content. If you - enable prevent-compression per - default, you might want to add exceptions for those sites. - See the example for how to do that. -
--
-
--# Selectively turn off compression, and enable a filter + + |
+
- Prevent yet another way to track the user's steps between - sessions. -
-- Deletes the "Last-Modified:" - HTTP server header or modifies its value. -
-- Parameterized. -
-- One of the keywords: "block", - "reset-to-request-time" and - "randomize" -
-- Removing the "Last-Modified:" - header is useful for filter testing, where you want to - force a real reload instead of getting status code "304", which would cause the browser - to reuse the old version of the page. -
-- The "randomize" option - overwrites the value of the "Last-Modified:" header with a randomly - chosen time between the original value and the current - time. In theory the server could send each document with a - different "Last-Modified:" - header to track visits without using cookies. "Randomize" makes it impossible and the - browser can still revalidate cached documents. -
-- "reset-to-request-time" - overwrites the value of the "Last-Modified:" header with the current - time. You could use this option together with hide-if-modified-since - to further customize your random range. -
-- The preferred parameter here is "randomize". It is safe to use, as long as - the time settings are more or less correct. If the server - sets the "Last-Modified:" header - to the time of the request, the random range becomes zero - and the value stays the same. Therefore you should later - randomize it a second time with hided-if-modified-since, - just to be sure. -
-- It is also recommended to use this action together with crunch-if-none-match. -
--
-
--# Let the browser revalidate without being tracked across sessions + + |
+
- Redirect requests to other sites. -
-- Convinces the browser that the requested document has been - moved to another location and the browser should get it - from there. -
-- Parameterized -
-- An absolute URL or a single pcrs command. -
-- Requests to which this action applies are answered with a - HTTP redirect to URLs of your choosing. The new URL is - either provided as parameter, or derived by applying a - single pcrs command to the original URL. -
-- This action will be ignored if you use it together with block. It can be - combined with fast-redirects{check-decoded-url} - to redirect to a decoded version of a rewritten URL. -
-- Use this action carefully, make sure not to create - redirection loops and be aware that using your own - redirects might make it possible to fingerprint your - requests. -
-- In case of problems with your redirects, or simply to watch - them working, enable debug - 128. -
--
-
--# Replace example.com's style sheet with another one + + |
+
- Rewrite or remove single server headers. -
-- All server headers to which this action applies are - filtered on-the-fly through the specified regular - expression based substitutions. -
-- Parameterized. -
-- The name of a server-header filter, as defined in one of - the filter files. -
-- Server-header filters are applied to each header on its - own, not to all at once. This makes it easier to diagnose - problems, but on the downside you can't write filters that - only change header x if header y's value is z. You can do - that by using tags though. -
-- Server-header filters are executed after the other header - actions have finished and use their output as input. -
-- Please refer to the filter file - chapter to learn which server-header filters are - available by default, and how to create your own. -
--
-
--{+server-header-filter{html-to-xml}} + + |
+
- Enable or disable filters based on the Content-Type header. -
-- Server headers to which this action applies are filtered - on-the-fly through the specified regular expression based - substitutions, the result is used as tag. -
-- Parameterized. -
-- The name of a server-header tagger, as defined in one of - the filter files. -
-- Server-header taggers are applied to each header on its - own, and as the header isn't modified, each tagger "sees" the original. -
-- Server-header taggers are executed before all other header - actions that modify server headers. Their tags can be used - to control all of the other server-header actions, the - content filters and the crunch actions (redirect and block). -
-- Obviously crunching based on tags created by server-header - taggers doesn't prevent the request from showing up in the - server's log file. -
--
-
--# Tag every request with the content type declared by the server + + |
+
- Choose the replacement for blocked images -
-- This action alone doesn't do anything noticeable. If both block and handle-as-image - also - apply, i.e. if the request is to be blocked as an image, - then - the parameter of this action decides what will be sent as a - replacement. -
-- Parameterized. -
-- "pattern" to send a built-in - checkerboard pattern image. The image is visually - decent, scales very well, and makes it obvious where - banners were busted. -
-- "blank" to send a built-in - transparent image. This makes banners disappear - completely, but makes it hard to detect where Privoxy has blocked images - on a given page and complicates troubleshooting if - Privoxy has blocked - innocent images, like navigation icons. -
-- "target-url" to send a - redirect to target-url. You can redirect - to any image anywhere, even in your local filesystem - via "file:///" URL. (But - note that not all browsers support redirecting to a - local file system). -
-- A good application of redirects is to use special Privoxy-built-in URLs, which - send the built-in images, as target-url. This has the same - visual effect as specifying "blank" or "pattern" in the first place, but - enables your browser to cache the replacement image, - instead of requesting it over and over again. -
-- The URLs for the built-in images are "http://config.privoxy.org/send-banner?type=type", where type is either "blank" or "pattern". -
-- There is a third (advanced) type, called "auto". It is NOT to be used in set-image-blocker, but meant for use from filters. Auto will select the - type of image that would have applied to the referring - page, had it been an image. -
-- Built-in pattern: -
--
-
--+set-image-blocker{pattern} -- |
-
- Redirect to the BSD daemon: -
--
-
--+set-image-blocker{http://www.freebsd.org/gifs/dae_up3.gif} -- |
-
- Redirect to the built-in pattern for better caching: -
--
-
--+set-image-blocker{http://config.privoxy.org/send-banner?type=pattern} -- |
-
Allow only temporary "session" cookies (for the current browser session + only).
+Deletes the "expires" field from "Set-Cookie:" + server headers. Most browsers will not store such cookies permanently and forget them in between + sessions.
+Boolean.
+N/A
+This is less strict than crunch-incoming-cookies / crunch-outgoing-cookies and allows + you to browse websites that insist or rely on setting cookies, without compromising your privacy too + badly.
+Most browsers will not permanently store cookies that have been processed by session-cookies-only and will forget about them between sessions. This makes profiling + cookies useless, but won't break sites which require cookies so that you can log in for transactions. + This is generally turned on for all sites, and is the recommended setting.
+It makes no sense at all to use session-cookies-only together with crunch-incoming-cookies or crunch-outgoing-cookies. If you + do, cookies will be plainly killed.
+Note that it is up to the browser how it handles such cookies without an "expires" field. If you use an exotic browser, you might want to try it out to be + sure.
+This setting also has no effect on cookies that may have been stored previously by the browser before + starting Privoxy. These would have to be removed manually.
+Privoxy also uses the content-cookies filter to block some types of cookies. + Content cookies are not effected by session-cookies-only.
+
+ +session-cookies-only+ |
+
- Note that many of these actions have the potential to cause a - page to misbehave, possibly even not to display at all. There are - many ways a site designer may choose to design his site, and what - HTTP header content, and other criteria, he may depend on. There - is no way to have hard and fast rules for all sites. See the Appendix for a brief example - on troubleshooting actions. -
+Choose the replacement for blocked images
+This action alone doesn't do anything noticeable. If both block + and handle-as-image also apply, i.e. if the request is to be blocked as an image, then the parameter of this action decides what will be sent as + a replacement.
+Parameterized.
+"pattern" to send a built-in checkerboard pattern image. The image is + visually decent, scales very well, and makes it obvious where banners were busted.
+"blank" to send a built-in transparent image. This makes banners + disappear completely, but makes it hard to detect where Privoxy has + blocked images on a given page and complicates troubleshooting if Privoxy has blocked innocent images, like navigation icons.
+"target-url" to send a redirect to + target-url. You can redirect to any image anywhere, even in your + local filesystem via "file:///" URL. (But note that not all browsers + support redirecting to a local file system).
+A good application of redirects is to use special Privoxy-built-in URLs, which send the built-in images, as target-url. This has the same visual effect as specifying "blank" or "pattern" in the first place, but enables your + browser to cache the replacement image, instead of requesting it over and over again.
+The URLs for the built-in images are "http://config.privoxy.org/send-banner?type=type", + where type is either "blank" or + "pattern".
+There is a third (advanced) type, called "auto". It is NOT to be used in set-image-blocker, + but meant for use from filters. Auto will select the type of image that + would have applied to the referring page, had it been an image.
+Built-in pattern:
+
+ +set-image-blocker{pattern}+ |
+
Redirect to the BSD daemon:
+
+ +set-image-blocker{http://www.freebsd.org/gifs/dae_up3.gif}+ |
+
Redirect to the built-in pattern for better caching:
+
+ +set-image-blocker{http://config.privoxy.org/send-banner?type=pattern}+ |
+
- Custom "actions", known to Privoxy as "aliases", can be defined by combining other - actions. These can in turn be invoked just like the built-in - actions. Currently, an alias name can contain any character except - space, tab, "=", "{" and "}", but we strongly recommend - that you only use "a" to "z", "0" to "9", "+", and "-". Alias names are not case sensitive, and - are not required to start with a "+" or - "-" sign, since they are merely - textually expanded. -
-- Aliases can be used throughout the actions file, but they must be defined in a special - section at the top of the file! And there can only be - one such section per actions file. Each actions file may have its - own alias section, and the aliases defined in it are only visible - within that file. -
-- There are two main reasons to use aliases: One is to save typing - for frequently used combinations of actions, the other one is a - gain in flexibility: If you decide once how you want to handle - shops by defining an alias called "shop", you can later change your policy on shops in - one place, - and your changes will take effect everywhere in the actions file - where the "shop" alias is used. Calling - aliases by their purpose also makes your actions files more - readable. -
-- Currently, there is one big drawback to using aliases, though: - Privoxy's built-in web-based - action file editor honors aliases when reading the actions files, - but it expands them before writing. So the effects of your aliases - are of course preserved, but the aliases themselves are lost when - you edit sections that use aliases with it. -
-- Now let's define some aliases... -
--
-
-- # Useful custom aliases we can use later. + |