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85 > The actions files are used to define what <SPAN
95 > takes for which URLs, and thus determines
96 how ad images, cookies and various other aspects of HTTP content and
97 transactions are handled, and on which sites (or even parts thereof).
98 There are a number of such actions, with a wide range of functionality.
99 Each action does something a little different.
100 These actions give us a veritable arsenal of tools with which to exert
101 our control, preferences and independence. Actions can be combined so that
102 their effects are aggregated when applied against a given set of URLs.</P
105 are three action files included with <SPAN
109 differing purposes:</P
118 >match-all.action</TT
119 > - is used to define which
123 > relating to banner-blocking, images, pop-ups,
124 content modification, cookie handling etc should be applied by default.
125 It should be the first actions file loaded
133 > - defines many exceptions (both
134 positive and negative) from the default set of actions that's configured
137 >match-all.action</TT
138 >. It is a set of rules that should
139 work reasonably well as-is for most users. This file is only supposed to
140 be edited by the developers. It should be the second actions file loaded.
148 > - is intended to be for local site
149 preferences and exceptions. As an example, if your ISP or your bank
150 has specific requirements, and need special handling, this kind of
151 thing should go here. This file will not be upgraded.
161 >Set to Cautious</SPAN
167 >Set to Advanced</SPAN
171 > These have increasing levels of aggressiveness <SPAN
176 influence on your browsing unless you select them explicitly in the
179 >. A default installation should be pre-set to
183 >. New users should try this for a while before
184 adjusting the settings to more aggressive levels. The more aggressive
185 the settings, then the more likelihood there is of problems such as sites
186 not working as they should.
192 > button allows you to turn each
193 action on/off individually for fine-tuning. The <SPAN
197 button changes the actions list to low/safe settings which will activate
198 ad blocking and a minimal set of <SPAN
201 >'s features, and subsequently
202 there will be less of a chance for accidental problems. The
206 > button sets the list to a medium level of
207 other features and a low level set of privacy features. The
211 > button sets the list to a high level of
212 ad blocking and medium level of privacy. See the chart below. The latter
213 three buttons over-ride any changes via with the
217 > button. More fine-tuning can be done in the
218 lower sections of this internal page.
221 > While the actions file editor allows to enable these settings in all
222 actions files, they are only supposed to be enabled in the first one
223 to make sure you don't unintentionally overrule earlier rules.
226 > The default profiles, and their associated actions, as pre-defined in
240 >Table 1. Default Configurations</B
270 >Ad-blocking Aggressiveness</TD
280 >Ad-filtering by size</TD
290 >Ad-filtering by link</TD
310 >Privacy Features</TD
340 >GIF de-animation</TD
370 >JavaScript taming</TD
390 >Image tag reordering</TD
407 > The list of actions files to be used are defined in the main configuration
408 file, and are processed in the order they are defined (e.g.
412 > is typically processed before
416 >). The content of these can all be viewed and
418 HREF="http://config.privoxy.org/show-status"
420 >http://config.privoxy.org/show-status</A
422 The over-riding principle when applying actions, is that the last action that
423 matches a given URL wins. The broadest, most general rules go first
428 followed by any exceptions (typically also in
432 >), which are then followed lastly by any
433 local preferences (typically in <SPAN
449 > An actions file typically has multiple sections. If you want to use
453 > in an actions file, you have to place the (optional)
455 HREF="actions-file.html#ALIASES"
457 > at the top of that file.
458 Then comes the default set of rules which will apply universally to all
459 sites and pages (be <SPAN
469 > or any other actions file after
473 >, because it will override the result
474 from consulting any previous file). And then below that,
475 exceptions to the defined universal policies. You can regard
479 > as an appendix to <TT
483 with the advantage that it is a separate file, which makes preserving your
484 personal settings across <SPAN
487 > upgrades easier.</P
490 Actions can be used to block anything you want, including ads, banners, or
491 just some obnoxious URL whose content you would rather not see. Cookies can be accepted
492 or rejected, or accepted only during the current browser session (i.e. not
493 written to disk), content can be modified, some JavaScripts tamed, user-tracking
494 fooled, and much more. See below for a <A
495 HREF="actions-file.html#ACTIONS"
505 >8.1. Finding the Right Mix</A
509 HREF="actions-file.html#ACTIONS"
511 >, like cookie suppression
512 or script disabling, may render some sites unusable that rely on these
513 techniques to work properly. Finding the right mix of actions is not always easy and
514 certainly a matter of personal taste. And, things can always change, requiring
515 refinements in the configuration. In general, it can be said that the more
519 > your default settings (in the top section of the
520 actions file) are, the more exceptions for <SPAN
524 will have to make later. If, for example, you want to crunch all cookies per
525 default, you'll have to make exceptions from that rule for sites that you
526 regularly use and that require cookies for actually useful purposes, like maybe
527 your bank, favorite shop, or newspaper.</P
529 > We have tried to provide you with reasonable rules to start from in the
530 distribution actions files. But there is no general rule of thumb on these
531 things. There just are too many variables, and sites are constantly changing.
532 Sooner or later you will want to change the rules (and read this chapter again :).</P
543 > The easiest way to edit the actions files is with a browser by
544 using our browser-based editor, which can be reached from <A
545 HREF="http://config.privoxy.org/show-status"
547 >http://config.privoxy.org/show-status</A
549 Note: the config file option <A
550 HREF="config.html#ENABLE-EDIT-ACTIONS"
551 >enable-edit-actions</A
552 > must be enabled for
553 this to work. The editor allows both fine-grained control over every single
554 feature on a per-URL basis, and easy choosing from wholesale sets of defaults
565 >. Warning: the <SPAN
569 aggressive, and will be more likely to cause problems for some sites.
570 Experienced users only!
573 > If you prefer plain text editing to GUIs, you can of course also directly edit the
574 the actions files with your favorite text editor. Look at
578 > which is richly commented with many
587 >8.3. How Actions are Applied to Requests</A
590 > Actions files are divided into sections. There are special sections,
594 HREF="actions-file.html#ALIASES"
597 > sections which will
598 be discussed later. For now let's concentrate on regular sections: They have a
599 heading line (often split up to multiple lines for readability) which consist
600 of a list of actions, separated by whitespace and enclosed in curly braces.
601 Below that, there is a list of URL and tag patterns, each on a separate line.</P
603 > To determine which actions apply to a request, the URL of the request is
604 compared to all URL patterns in each <SPAN
608 Every time it matches, the list of applicable actions for the request is
609 incrementally updated, using the heading of the section in which the
610 pattern is located. The same is done again for tags and tag patterns later on.</P
612 > If multiple applying sections set the same action differently,
613 the last match wins. If not, the effects are aggregated.
614 E.g. a URL might match a regular section with a heading line of <TT
618 HREF="actions-file.html#HANDLE-AS-IMAGE"
622 then later another one with just <TT
626 HREF="actions-file.html#BLOCK"
636 > actions to apply. And there may well be
637 cases where you will want to combine actions together. Such a section then
653 >block{Banner ads.}</TT
655 # Block these as if they were images. Send no block page.
657 media.example.com/.*banners
658 .example.com/images/ads/</PRE
665 > You can trace this process for URL patterns and any given URL by visiting <A
666 HREF="http://config.privoxy.org/show-url-info"
668 >http://config.privoxy.org/show-url-info</A
671 > Examples and more detail on this is provided in the Appendix, <A
672 HREF="appendix.html#ACTIONSANAT"
673 > Troubleshooting: Anatomy of an Action</A
693 to determine what <SPAN
699 > might apply to which sites and
700 pages your browser attempts to access. These <SPAN
710 > matching to achieve a high degree of
711 flexibility. This allows one expression to be expanded and potentially match
712 against many similar patterns.</P
714 > Generally, an URL pattern has the form
717 ><domain>/<path></TT
721 ><domain></TT
726 optional. (This is why the special <TT
729 > pattern matches all
730 URLs). Note that the protocol portion of the URL pattern (e.g.
741 the pattern. This is assumed already!</P
743 > The pattern matching syntax is different for the domain and path parts of
744 the URL. The domain part uses a simple globbing type matching technique,
745 while the path part uses more flexible
747 HREF="http://en.wikipedia.org/wiki/Regular_expressions"
763 >www.example.com/</TT
767 > is a domain-only pattern and will match any request to <TT
771 regardless of which document on that server is requested. So ALL pages in
772 this domain would be covered by the scope of this action. Note that a
776 > is different and would NOT match.
786 > means exactly the same. For domain-only patterns, the trailing <TT
796 >www.example.com/index.html</TT
800 > matches all the documents on <TT
804 whose name starts with <TT
813 >www.example.com/index.html$</TT
817 > matches only the single document <TT
834 > matches the document <TT
837 >, regardless of the domain,
844 > web server anywhere.
854 > matches nothing, since it would be interpreted as a domain name and
855 there is no top-level domain called <TT
870 >8.4.1. The Domain Pattern</A
873 > The matching of the domain part offers some flexible options: if the
874 domain starts or ends with a dot, it becomes unanchored at that end.
888 > matches any domain with first-level domain <TT
892 and second-level domain <TT
905 >foo.bar.baz.example.com</TT
907 Note that it wouldn't match if the second-level domain was <TT
920 > matches any domain that <SPAN
930 > (It also matches the domain
934 > but most of the time that doesn't matter.)
944 > matches any domain that <SPAN
954 And, by the way, also included would be any files or documents that exist
955 within that domain since no path limitations are specified. (Correctly
956 speaking: It matches any FQDN that contains <TT
960 a domain.) This might be <TT
970 >www.example.net/cgi/testing.pl</TT
971 > for instance. All these
978 > Additionally, there are wild-cards that you can use in the domain names
979 themselves. These work similarly to shell globbing type wild-cards:
983 > represents zero or more arbitrary characters (this is
986 HREF="http://en.wikipedia.org/wiki/Regular_expressions"
993 > based syntax of <SPAN
1000 > represents any single character (this is equivalent to the
1001 regular expression syntax of a simple <SPAN
1004 >), and you can define
1007 >"character classes"</SPAN
1008 > in square brackets which is similar to
1009 the same regular expression technique. All of this can be freely mixed:</P
1013 CLASS="VARIABLELIST"
1018 >ad*.example.com</TT
1024 >"adserver.example.com"</SPAN
1028 >"ads.example.com"</SPAN
1029 >, etc but not <SPAN
1031 >"sfads.example.com"</SPAN
1038 >*ad*.example.com</TT
1042 > matches all of the above, and then some.
1058 >pictures.epix.com</TT
1061 >a.b.c.d.e.upix.com</TT
1068 >www[1-9a-ez].example.c*</TT
1074 >www1.example.com</TT
1078 >www4.example.cc</TT
1081 >wwwd.example.cy</TT
1085 >wwwz.example.com</TT
1095 >wwww.example.com</TT
1102 > While flexible, this is not the sophistication of full regular expression based syntax.</P
1110 >8.4.2. The Path Pattern</A
1121 HREF="http://en.wikipedia.org/wiki/Regular_expressions"
1128 > for matching the path portion (after the slash),
1129 and is thus more flexible.</P
1132 HREF="appendix.html#REGEX"
1134 > with a brief quick-start into regular
1135 expressions, you also might want to have a look at your operating system's documentation
1136 on regular expressions (try <TT
1141 > Note that the path pattern is automatically left-anchored at the <SPAN
1145 i.e. it matches as if it would start with a <SPAN
1148 > (regular expression speak
1149 for the beginning of a line).</P
1151 > Please also note that matching in the path is <SPAN
1155 >CASE INSENSITIVE</I
1158 by default, but you can switch to case sensitive at any point in the pattern by using the
1164 >www.example.com/(?-i)PaTtErN.*</TT
1166 only documents whose path starts with <TT
1176 > this capitalization.</P
1180 CLASS="VARIABLELIST"
1185 >.example.com/.*</TT
1189 > Is equivalent to just <SPAN
1191 >".example.com"</SPAN
1192 >, since any documents
1193 within that domain are matched with or without the <SPAN
1197 regular expression. This is redundant
1203 >.example.com/.*/index.html$</TT
1207 > Will match any page in the domain of <SPAN
1209 >"example.com"</SPAN
1214 >, and that is part of some path. For
1215 example, it matches <SPAN
1217 >"www.example.com/testing/index.html"</SPAN
1221 >"www.example.com/index.html"</SPAN
1222 > because the regular
1223 expression called for at least two <SPAN
1227 requirement. It also would match
1230 >"www.example.com/testing/index_html"</SPAN
1232 special meta-character <SPAN
1241 >.example.com/(.*/)?index\.html$</TT
1245 > This regular expression is conditional so it will match any page
1249 > regardless of path which in this case can
1250 have one or more <SPAN
1253 >. And this one must contain exactly
1257 > (but does not have to end with that!).
1263 >.example.com/(.*/)(ads|banners?|junk)</TT
1267 > This regular expression will match any path of <SPAN
1269 >"example.com"</SPAN
1271 that contains any of the words <SPAN
1281 > (because of the <SPAN
1288 The path does not have to end in these words, just contain them.
1294 >.example.com/(.*/)(ads|banners?|junk)/.*\.(jpe?g|gif|png)$</TT
1298 > This is very much the same as above, except now it must end in either
1312 one is limited to common image formats.
1318 > There are many, many good examples to be found in <TT
1322 and more tutorials below in <A
1323 HREF="appendix.html#REGEX"
1324 >Appendix on regular expressions</A
1333 >8.4.3. The Tag Pattern</A
1336 > Tag patterns are used to change the applying actions based on the
1337 request's tags. Tags can be created with either the
1339 HREF="actions-file.html#CLIENT-HEADER-TAGGER"
1340 >client-header-tagger</A
1343 HREF="actions-file.html#SERVER-HEADER-TAGGER"
1344 >server-header-tagger</A
1347 > Tag patterns have to start with <SPAN
1354 can tell them apart from URL patterns. Everything after the colon
1355 including white space, is interpreted as a regular expression with
1356 path pattern syntax, except that tag patterns aren't left-anchored
1357 automatically (<SPAN
1360 > doesn't silently add a <SPAN
1364 you have to do it yourself if you need it).</P
1366 > To match all requests that are tagged with <SPAN
1370 your pattern line should be <SPAN
1377 > would work as well, but it would also
1378 match requests whose tags contain <SPAN
1385 > wouldn't work as it requires white space.</P
1387 > Sections can contain URL and tag patterns at the same time,
1388 but tag patterns are checked after the URL patterns and thus
1389 always overrule them, even if they are located before the URL patterns.</P
1391 > Once a new tag is added, Privoxy checks right away if it's matched by one
1392 of the tag patterns and updates the action settings accordingly. As a result
1393 tags can be used to activate other tagger actions, as long as these other
1394 taggers look for headers that haven't already be parsed.</P
1396 > For example you could tag client requests which use the
1401 then use this tag to activate another tagger that adds a tag if cookies
1402 are sent, and then use a block action based on the cookie tag. This allows
1403 the outcome of one action, to be input into a subsequent action. However if
1404 you'd reverse the position of the described taggers, and activated the
1405 method tagger based on the cookie tagger, no method tags would be created.
1406 The method tagger would look for the request line, but at the time
1407 the cookie tag is created, the request line has already been parsed.</P
1409 > While this is a limitation you should be aware of, this kind of
1410 indirection is seldom needed anyway and even the example doesn't
1411 make too much sense.</P
1423 > All actions are disabled by default, until they are explicitly enabled
1424 somewhere in an actions file. Actions are turned on if preceded with a
1428 >, and turned off if preceded with a <SPAN
1437 >"do that action"</SPAN
1444 >"please block URLs that match the
1445 following patterns"</SPAN
1452 block URLs that match the following patterns, even if <TT
1456 previously applied."</SPAN
1460 Again, actions are invoked by placing them on a line, enclosed in curly braces and
1461 separated by whitespace, like in
1464 >{+some-action -some-other-action{some-parameter}}</TT
1466 followed by a list of URL patterns, one per line, to which they apply.
1467 Together, the actions line and the following pattern lines make up a section
1468 of the actions file. </P
1471 Actions fall into three categories:</P
1479 Boolean, i.e the action can only be <SPAN
1502 > # enable action <TT
1513 > # disable action <TT
1528 >+handle-as-image</TT
1535 Parameterized, where some value is required in order to enable this type of action.
1557 >} # enable action and set parameter to <TT
1563 # overwriting parameter from previous match if necessary
1569 > # disable action. The parameter can be omitted</PRE
1576 > Note that if the URL matches multiple positive forms of a parameterized action,
1577 the last match wins, i.e. the params from earlier matches are simply ignored.
1583 >+hide-user-agent{Mozilla/5.0 (X11; U; FreeBSD i386; en-US; rv:1.8.1.4) Gecko/20070602 Firefox/2.0.0.4}</TT
1590 Multi-value. These look exactly like parameterized actions,
1591 but they behave differently: If the action applies multiple times to the
1592 same URL, but with different parameters, <SPAN
1605 > matches are remembered. This is used for actions
1606 that can be executed for the same request repeatedly, like adding multiple
1607 headers, or filtering through multiple filters. Syntax:
1628 >} # enable action and add <TT
1633 > to the list of parameters
1644 >} # remove the parameter <TT
1649 > from the list of parameters
1650 # If it was the last one left, disable the action.
1656 > # disable this action completely and remove all parameters from the list</PRE
1666 >+add-header{X-Fun-Header: Some text}</TT
1670 >+filter{html-annoyances}</TT
1677 > If nothing is specified in any actions file, no <SPAN
1681 taken. So in this case <SPAN
1685 normal, non-blocking, non-filtering proxy. You must specifically enable the
1686 privacy and blocking features you need (although the provided default actions
1687 files will give a good starting point).</P
1689 > Later defined action sections always over-ride earlier ones of the same type.
1690 So exceptions to any rules you make, should come in the latter part of the file (or
1691 in a file that is processed later when using multiple actions files such
1695 >). For multi-valued actions, the actions
1696 are applied in the order they are specified. Actions files are processed in
1697 the order they are defined in <TT
1701 installation has three actions files). It also quite possible for any given
1702 URL to match more than one <SPAN
1705 > (because of wildcards and
1706 regular expressions), and thus to trigger more than one set of actions! Last
1709 > The list of valid <SPAN
1719 >8.5.1. add-header</A
1724 CLASS="VARIABLELIST"
1730 >Confuse log analysis, custom applications</P
1736 > Sends a user defined HTTP header to the web server.
1749 > Any string value is possible. Validity of the defined HTTP headers is not checked.
1750 It is recommended that you use the <SPAN
1764 > This action may be specified multiple times, in order to define multiple
1765 headers. This is rarely needed for the typical user. If you don't know what
1768 >"HTTP headers"</SPAN
1769 > are, you definitely don't need to worry about this
1785 >+add-header{X-User-Tracking: sucks}</PRE
1806 CLASS="VARIABLELIST"
1812 >Block ads or other unwanted content</P
1818 > Requests for URLs to which this action applies are blocked, i.e. the
1819 requests are trapped by <SPAN
1822 > and the requested URL is never retrieved,
1823 but is answered locally with a substitute page or image, as determined by
1827 HREF="actions-file.html#HANDLE-AS-IMAGE"
1834 HREF="actions-file.html#SET-IMAGE-BLOCKER"
1835 >set-image-blocker</A
1841 HREF="actions-file.html#HANDLE-AS-EMPTY-DOCUMENT"
1842 >handle-as-empty-document</A
1858 >A block reason that should be given to the user.</P
1867 > sends a special <SPAN
1871 for requests to blocked pages. This page contains the block reason given as
1872 parameter, a link to find out why the block action applies, and a click-through
1873 to the blocked content (the latter only if the force feature is available and
1878 A very important exception occurs if <SPAN
1891 HREF="actions-file.html#HANDLE-AS-IMAGE"
1895 apply to the same request: it will then be replaced by an image. If
1899 HREF="actions-file.html#SET-IMAGE-BLOCKER"
1900 >set-image-blocker</A
1903 (see below) also applies, the type of image will be determined by its parameter,
1904 if not, the standard checkerboard pattern is sent.
1907 > It is important to understand this process, in order
1908 to understand how <SPAN
1912 ads and other unwanted content. Blocking is a core feature, and one
1913 upon which various other features depend.
1919 HREF="actions-file.html#FILTER"
1923 action can perform a very similar task, by <SPAN
1927 banner images and other content through rewriting the relevant URLs in the
1928 document's HTML source, so they don't get requested in the first place.
1929 Note that this is a totally different technique, and it's easy to confuse the two.
1933 >Example usage (section):</DT
1944 >{+block{No nasty stuff for you.}}
1945 # Block and replace with "blocked" page
1946 .nasty-stuff.example.com
1948 {+block{Doubleclick banners.} +handle-as-image}
1949 # Block and replace with image
1953 {+block{Layered ads.} +handle-as-empty-document}
1954 # Block and then ignore
1955 adserver.example.net/.*\.js$</PRE
1970 NAME="CHANGE-X-FORWARDED-FOR"
1971 >8.5.3. change-x-forwarded-for</A
1976 CLASS="VARIABLELIST"
1982 >Improve privacy by not forwarding the source of the request in the HTTP headers.</P
1990 >"X-Forwarded-For:"</SPAN
1991 > HTTP header from the client request,
2012 > to delete the header.</P
2019 > to create the header (or append
2020 the client's IP address to an already existing one).
2029 > It is safe and recommended to use <TT
2035 > Forwarding the source address of the request may make
2036 sense in some multi-user setups but is also a privacy risk.
2051 >+change-x-forwarded-for{block}</PRE
2066 NAME="CLIENT-HEADER-FILTER"
2067 >8.5.4. client-header-filter</A
2072 CLASS="VARIABLELIST"
2078 > Rewrite or remove single client headers.
2085 > All client headers to which this action applies are filtered on-the-fly through
2086 the specified regular expression based substitutions.
2099 > The name of a client-header filter, as defined in one of the
2101 HREF="filter-file.html"
2110 > Client-header filters are applied to each header on its own, not to
2111 all at once. This makes it easier to diagnose problems, but on the downside
2112 you can't write filters that only change header x if header y's value is z.
2113 You can do that by using tags though.
2116 > Client-header filters are executed after the other header actions have finished
2117 and use their output as input.
2120 > If the request URL gets changed, <SPAN
2123 > will detect that and use the new
2124 one. This can be used to rewrite the request destination behind the client's
2125 back, for example to specify a Tor exit relay for certain requests.
2128 > Please refer to the <A
2129 HREF="filter-file.html"
2130 >filter file chapter</A
2132 to learn which client-header filters are available by default, and how to
2137 >Example usage (section):</DT
2148 ># Hide Tor exit notation in Host and Referer Headers
2149 {+client-header-filter{hide-tor-exit-notation}}
2166 NAME="CLIENT-HEADER-TAGGER"
2167 >8.5.5. client-header-tagger</A
2172 CLASS="VARIABLELIST"
2178 > Block requests based on their headers.
2185 > Client headers to which this action applies are filtered on-the-fly through
2186 the specified regular expression based substitutions, the result is used as
2200 > The name of a client-header tagger, as defined in one of the
2202 HREF="filter-file.html"
2211 > Client-header taggers are applied to each header on its own,
2212 and as the header isn't modified, each tagger <SPAN
2219 > Client-header taggers are the first actions that are executed
2220 and their tags can be used to control every other action.
2224 >Example usage (section):</DT
2235 ># Tag every request with the User-Agent header
2236 {+client-header-tagger{user-agent}}
2239 # Tagging itself doesn't change the action
2240 # settings, sections with TAG patterns do:
2242 # If it's a download agent, use a different forwarding proxy,
2243 # show the real User-Agent and make sure resume works.
2244 {+forward-override{forward-socks5 10.0.0.2:2222 .} \
2245 -hide-if-modified-since \
2246 -overwrite-last-modified \
2251 TAG:^User-Agent: NetBSD-ftp/
2252 TAG:^User-Agent: Novell ZYPP Installer
2253 TAG:^User-Agent: RPM APT-HTTP/
2254 TAG:^User-Agent: fetch libfetch/
2255 TAG:^User-Agent: Ubuntu APT-HTTP/
2256 TAG:^User-Agent: MPlayer/
2272 NAME="CONTENT-TYPE-OVERWRITE"
2273 >8.5.6. content-type-overwrite</A
2278 CLASS="VARIABLELIST"
2284 >Stop useless download menus from popping up, or change the browser's rendering mode</P
2290 > Replaces the <SPAN
2292 >"Content-Type:"</SPAN
2293 > HTTP server header.
2315 >"Content-Type:"</SPAN
2316 > HTTP server header is used by the
2317 browser to decide what to do with the document. The value of this
2318 header can cause the browser to open a download menu instead of
2319 displaying the document by itself, even if the document's format is
2320 supported by the browser.
2323 > The declared content type can also affect which rendering mode
2324 the browser chooses. If XHTML is delivered as <SPAN
2328 many browsers treat it as yet another broken HTML document.
2329 If it is send as <SPAN
2331 >"application/xml"</SPAN
2333 XHTML support will only display it, if the syntax is correct.
2336 > If you see a web site that proudly uses XHTML buttons, but sets
2339 >"Content-Type: text/html"</SPAN
2340 >, you can use <SPAN
2344 to overwrite it with <SPAN
2346 >"application/xml"</SPAN
2348 the web master's claim inside your XHTML-supporting browser.
2349 If the syntax is incorrect, the browser will complain loudly.
2352 > You can also go the opposite direction: if your browser prints
2353 error messages instead of rendering a document falsely declared
2354 as XHTML, you can overwrite the content type with
2358 > and have it rendered as broken HTML document.
2363 >content-type-overwrite</TT
2367 >"Content-Type:"</SPAN
2368 > headers that look like some kind of text.
2369 If you want to overwrite it unconditionally, you have to combine it with
2373 HREF="actions-file.html#FORCE-TEXT-MODE"
2377 This limitation exists for a reason, think twice before circumventing it.
2380 > Most of the time it's easier to replace this action with a custom
2384 HREF="actions-file.html#SERVER-HEADER-FILTER"
2385 >server-header filter</A
2388 It allows you to activate it for every document of a certain site and it will still
2389 only replace the content types you aimed at.
2392 > Of course you can apply <TT
2394 >content-type-overwrite</TT
2396 to a whole site and then make URL based exceptions, but it's a lot
2397 more work to get the same precision.
2401 >Example usage (sections):</DT
2412 ># Check if www.example.net/ really uses valid XHTML
2413 { +content-type-overwrite{application/xml} }
2416 # but leave the content type unmodified if the URL looks like a style sheet
2417 {-content-type-overwrite}
2418 www.example.net/.*\.css$
2419 www.example.net/.*style</PRE
2434 NAME="CRUNCH-CLIENT-HEADER"
2435 >8.5.7. crunch-client-header</A
2440 CLASS="VARIABLELIST"
2446 >Remove a client header <SPAN
2449 > has no dedicated action for.</P
2455 > Deletes every header sent by the client that contains the string the user supplied as parameter.
2475 > This action allows you to block client headers for which no dedicated
2483 > will remove every client header that
2484 contains the string you supplied as parameter.
2487 > Regular expressions are <SPAN
2494 use this action to block different headers in the same request, unless
2495 they contain the same string.
2500 >crunch-client-header</TT
2501 > is only meant for quick tests.
2502 If you have to block several different headers, or only want to modify
2503 parts of them, you should use a
2507 HREF="actions-file.html#CLIENT-HEADER-FILTER"
2508 >client-header filter</A
2531 > Don't block any header without understanding the consequences.
2539 >Example usage (section):</DT
2550 ># Block the non-existent "Privacy-Violation:" client header
2551 { +crunch-client-header{Privacy-Violation:} }
2568 NAME="CRUNCH-IF-NONE-MATCH"
2569 >8.5.8. crunch-if-none-match</A
2574 CLASS="VARIABLELIST"
2580 >Prevent yet another way to track the user's steps between sessions.</P
2588 >"If-None-Match:"</SPAN
2589 > HTTP client header.
2609 > Removing the <SPAN
2611 >"If-None-Match:"</SPAN
2612 > HTTP client header
2613 is useful for filter testing, where you want to force a real
2614 reload instead of getting status code <SPAN
2618 would cause the browser to use a cached copy of the page.
2621 > It is also useful to make sure the header isn't used as a cookie
2622 replacement (unlikely but possible).
2625 > Blocking the <SPAN
2627 >"If-None-Match:"</SPAN
2628 > header shouldn't cause any
2629 caching problems, as long as the <SPAN
2631 >"If-Modified-Since:"</SPAN
2633 isn't blocked or missing as well.
2636 > It is recommended to use this action together with
2640 HREF="actions-file.html#HIDE-IF-MODIFIED-SINCE"
2641 >hide-if-modified-since</A
2648 HREF="actions-file.html#OVERWRITE-LAST-MODIFIED"
2649 >overwrite-last-modified</A
2655 >Example usage (section):</DT
2666 ># Let the browser revalidate cached documents but don't
2667 # allow the server to use the revalidation headers for user tracking.
2668 {+hide-if-modified-since{-60} \
2669 +overwrite-last-modified{randomize} \
2670 +crunch-if-none-match}
2686 NAME="CRUNCH-INCOMING-COOKIES"
2687 >8.5.9. crunch-incoming-cookies</A
2692 CLASS="VARIABLELIST"
2698 > Prevent the web server from setting HTTP cookies on your system
2707 >"Set-Cookie:"</SPAN
2708 > HTTP headers from server replies.
2728 > This action is only concerned with <SPAN
2745 HREF="actions-file.html#CRUNCH-OUTGOING-COOKIES"
2746 >crunch-outgoing-cookies</A
2755 > to disable HTTP cookies completely.
2764 > to use this action in conjunction
2768 HREF="actions-file.html#SESSION-COOKIES-ONLY"
2769 >session-cookies-only</A
2772 since it would prevent the session cookies from being set. See also
2776 HREF="actions-file.html#FILTER-CONTENT-COOKIES"
2777 >filter-content-cookies</A
2794 >+crunch-incoming-cookies</PRE
2809 NAME="CRUNCH-SERVER-HEADER"
2810 >8.5.10. crunch-server-header</A
2815 CLASS="VARIABLELIST"
2821 >Remove a server header <SPAN
2824 > has no dedicated action for.</P
2830 > Deletes every header sent by the server that contains the string the user supplied as parameter.
2850 > This action allows you to block server headers for which no dedicated
2854 > action exists. <SPAN
2858 will remove every server header that contains the string you supplied as parameter.
2861 > Regular expressions are <SPAN
2868 use this action to block different headers in the same request, unless
2869 they contain the same string.
2874 >crunch-server-header</TT
2875 > is only meant for quick tests.
2876 If you have to block several different headers, or only want to modify
2877 parts of them, you should use a custom
2881 HREF="actions-file.html#SERVER-HEADER-FILTER"
2882 >server-header filter</A
2905 > Don't block any header without understanding the consequences.
2913 >Example usage (section):</DT
2924 ># Crunch server headers that try to prevent caching
2925 { +crunch-server-header{no-cache} }
2941 NAME="CRUNCH-OUTGOING-COOKIES"
2942 >8.5.11. crunch-outgoing-cookies</A
2947 CLASS="VARIABLELIST"
2953 > Prevent the web server from reading any HTTP cookies from your system
2963 > HTTP headers from client requests.
2983 > This action is only concerned with <SPAN
3000 HREF="actions-file.html#CRUNCH-INCOMING-COOKIES"
3001 >crunch-incoming-cookies</A
3010 > to disable HTTP cookies completely.
3019 > to use this action in conjunction
3023 HREF="actions-file.html#SESSION-COOKIES-ONLY"
3024 >session-cookies-only</A
3027 since it would prevent the session cookies from being read.
3042 >+crunch-outgoing-cookies</PRE
3057 NAME="DEANIMATE-GIFS"
3058 >8.5.12. deanimate-gifs</A
3063 CLASS="VARIABLELIST"
3069 >Stop those annoying, distracting animated GIF images.</P
3075 > De-animate GIF animations, i.e. reduce them to their first or last image.
3101 > This will also shrink the images considerably (in bytes, not pixels!). If
3105 > is given, the first frame of the animation
3106 is used as the replacement. If <SPAN
3109 > is given, the last
3110 frame of the animation is used instead, which probably makes more sense for
3111 most banner animations, but also has the risk of not showing the entire
3112 last frame (if it is only a delta to an earlier frame).
3115 > You can safely use this action with patterns that will also match non-GIF
3116 objects, because no attempt will be made at anything that doesn't look like
3132 >+deanimate-gifs{last}</PRE
3147 NAME="DOWNGRADE-HTTP-VERSION"
3148 >8.5.13. downgrade-http-version</A
3153 CLASS="VARIABLELIST"
3159 >Work around (very rare) problems with HTTP/1.1</P
3165 > Downgrades HTTP/1.1 client requests and server replies to HTTP/1.0.
3185 > This is a left-over from the time when <SPAN
3189 didn't support important HTTP/1.1 features well. It is left here for the
3190 unlikely case that you experience HTTP/1.1 related problems with some server
3191 out there. Not all HTTP/1.1 features and requirements are supported yet,
3192 so there is a chance you might need this action.
3196 >Example usage (section):</DT
3207 >{+downgrade-http-version}
3208 problem-host.example.com</PRE
3223 NAME="FAST-REDIRECTS"
3224 >8.5.14. fast-redirects</A
3229 CLASS="VARIABLELIST"
3235 >Fool some click-tracking scripts and speed up indirect links.</P
3241 > Detects redirection URLs and redirects the browser without contacting
3242 the redirection server first.
3261 >"simple-check"</SPAN
3262 > to just search for the string <SPAN
3266 to detect redirection URLs.
3273 >"check-decoded-url"</SPAN
3274 > to decode URLs (if necessary) before searching
3275 for redirection URLs.
3285 Many sites, like yahoo.com, don't just link to other sites. Instead, they
3286 will link to some script on their own servers, giving the destination as a
3287 parameter, which will then redirect you to the final target. URLs
3288 resulting from this scheme typically look like:
3291 >"http://www.example.org/click-tracker.cgi?target=http%3a//www.example.net/"</SPAN
3295 > Sometimes, there are even multiple consecutive redirects encoded in the
3296 URL. These redirections via scripts make your web browsing more traceable,
3297 since the server from which you follow such a link can see where you go
3298 to. Apart from that, valuable bandwidth and time is wasted, while your
3299 browser asks the server for one redirect after the other. Plus, it feeds
3303 > This feature is currently not very smart and is scheduled for improvement.
3304 If it is enabled by default, you will have to create some exceptions to
3305 this action. It can lead to failures in several ways:
3308 > Not every URLs with other URLs as parameters is evil.
3309 Some sites offer a real service that requires this information to work.
3310 For example a validation service needs to know, which document to validate.
3314 > assumes that every URL parameter that
3315 looks like another URL is a redirection target, and will always redirect to
3316 the last one. Most of the time the assumption is correct, but if it isn't,
3317 the user gets redirected anyway.
3320 > Another failure occurs if the URL contains other parameters after the URL parameter.
3324 >"http://www.example.org/?redirect=http%3a//www.example.net/&foo=bar"</SPAN
3326 contains the redirection URL <SPAN
3328 >"http://www.example.net/"</SPAN
3330 followed by another parameter. <TT
3334 and will cause a redirect to <SPAN
3336 >"http://www.example.net/&foo=bar"</SPAN
3338 Depending on the target server configuration, the parameter will be silently ignored
3341 >"page not found"</SPAN
3342 > error. You can prevent this problem by
3346 HREF="actions-file.html#REDIRECT"
3350 to remove the last part of the URL, but it requires a little effort.
3353 > To detect a redirection URL, <TT
3357 looks for the string <SPAN
3360 >, either in plain text
3361 (invalid but often used) or encoded as <SPAN
3365 Some sites use their own URL encoding scheme, encrypt the address
3366 of the target server or replace it with a database id. In theses cases
3370 > is fooled and the request reaches the
3371 redirection server where it probably gets logged.
3386 > { +fast-redirects{simple-check} }
3389 { +fast-redirects{check-decoded-url} }
3390 another.example.com/testing</PRE
3411 CLASS="VARIABLELIST"
3417 >Get rid of HTML and JavaScript annoyances, banner advertisements (by size),
3418 do fun text replacements, add personalized effects, etc.</P
3424 > All instances of text-based type, most notably HTML and JavaScript, to which
3425 this action applies, can be filtered on-the-fly through the specified regular
3426 expression based substitutions. (Note: as of version 3.0.3 plain text documents
3427 are exempted from filtering, because web servers often use the
3431 > MIME type for all files whose type they don't know.)
3444 > The name of a content filter, as defined in the <A
3445 HREF="filter-file.html"
3448 Filters can be defined in one or more files as defined by the
3452 HREF="config.html#FILTERFILE"
3463 > is the collection of filters
3464 supplied by the developers. Locally defined filters should go
3465 in their own file, such as <TT
3471 > When used in its negative form,
3472 and without parameters, <SPAN
3478 > filtering is completely disabled.
3485 > For your convenience, there are a number of pre-defined filters available
3486 in the distribution filter file that you can use. See the examples below for
3490 > Filtering requires buffering the page content, which may appear to
3491 slow down page rendering since nothing is displayed until all content has
3492 passed the filters. (It does not really take longer, but seems that way
3493 since the page is not incrementally displayed.) This effect will be more
3494 noticeable on slower connections.
3499 >"Rolling your own"</SPAN
3501 filters requires a knowledge of
3503 HREF="http://en.wikipedia.org/wiki/Regular_expressions"
3512 HREF="http://en.wikipedia.org/wiki/Html"
3519 This is very powerful feature, and potentially very intrusive.
3520 Filters should be used with caution, and where an equivalent
3527 > The amount of data that can be filtered is limited to the
3531 HREF="config.html#BUFFER-LIMIT"
3535 option in the main <A
3539 default is 4096 KB (4 Megs). Once this limit is exceeded, the buffered
3540 data, and all pending data, is passed through unfiltered.
3543 > Inappropriate MIME types, such as zipped files, are not filtered at all.
3544 (Again, only text-based types except plain text). Encrypted SSL data
3545 (from HTTPS servers) cannot be filtered either, since this would violate
3546 the integrity of the secure transaction. In some situations it might
3547 be necessary to protect certain text, like source code, from filtering
3548 by defining appropriate <TT
3554 > Compressed content can't be filtered either, unless <SPAN
3558 is compiled with zlib support (requires at least <SPAN
3565 > will decompress the content before filtering
3569 > If you use a <SPAN
3572 > version without zlib support, but want filtering to work on
3573 as much documents as possible, even those that would normally be sent compressed,
3574 you must use the <TT
3577 HREF="actions-file.html#PREVENT-COMPRESSION"
3578 >prevent-compression</A
3581 action in conjunction with <TT
3587 > Content filtering can achieve some of the same effects as the
3591 HREF="actions-file.html#BLOCK"
3595 action, i.e. it can be used to block ads and banners. But the mechanism
3596 works quite differently. One effective use, is to block ad banners
3597 based on their size (see below), since many of these seem to be somewhat
3604 > with suggestions for new or
3605 improved filters is particularly welcome!
3608 > The below list has only the names and a one-line description of each
3609 predefined filter. There are <A
3610 HREF="filter-file.html#PREDEFINED-FILTERS"
3612 verbose explanations</A
3613 > of what these filters do in the <A
3614 HREF="filter-file.html"
3615 >filter file chapter</A
3620 >Example usage (with filters from the distribution <TT
3625 HREF="filter-file.html#PREDEFINED-FILTERS"
3626 >the Predefined Filters section</A
3628 more explanation on each:</DT
3632 NAME="FILTER-JS-ANNOYANCES"
3643 >+filter{js-annoyances} # Get rid of particularly annoying JavaScript abuse.</PRE
3651 NAME="FILTER-JS-EVENTS"
3662 >+filter{js-events} # Kill all JS event bindings and timers (Radically destructive! Only for extra nasty sites).</PRE
3670 NAME="FILTER-HTML-ANNOYANCES"
3681 >+filter{html-annoyances} # Get rid of particularly annoying HTML abuse.</PRE
3689 NAME="FILTER-CONTENT-COOKIES"
3700 >+filter{content-cookies} # Kill cookies that come in the HTML or JS content.</PRE
3708 NAME="FILTER-REFRESH-TAGS"
3719 >+filter{refresh-tags} # Kill automatic refresh tags (for dial-on-demand setups).</PRE
3727 NAME="FILTER-UNSOLICITED-POPUPS"
3738 >+filter{unsolicited-popups} # Disable only unsolicited pop-up windows. Useful if your browser lacks this ability.</PRE
3746 NAME="FILTER-ALL-POPUPS"
3757 >+filter{all-popups} # Kill all popups in JavaScript and HTML. Useful if your browser lacks this ability.</PRE
3765 NAME="FILTER-IMG-REORDER"
3776 >+filter{img-reorder} # Reorder attributes in <img> tags to make the banners-by-* filters more effective.</PRE
3784 NAME="FILTER-BANNERS-BY-SIZE"
3795 >+filter{banners-by-size} # Kill banners by size.</PRE
3803 NAME="FILTER-BANNERS-BY-LINK"
3814 >+filter{banners-by-link} # Kill banners by their links to known clicktrackers.</PRE
3822 NAME="FILTER-WEBBUGS"
3833 >+filter{webbugs} # Squish WebBugs (1x1 invisible GIFs used for user tracking).</PRE
3841 NAME="FILTER-TINY-TEXTFORMS"
3852 >+filter{tiny-textforms} # Extend those tiny textareas up to 40x80 and kill the hard wrap.</PRE
3860 NAME="FILTER-JUMPING-WINDOWS"
3871 >+filter{jumping-windows} # Prevent windows from resizing and moving themselves.</PRE
3879 NAME="FILTER-FRAMESET-BORDERS"
3890 >+filter{frameset-borders} # Give frames a border and make them resizable.</PRE
3898 NAME="FILTER-DEMORONIZER"
3909 >+filter{demoronizer} # Fix MS's non-standard use of standard charsets.</PRE
3917 NAME="FILTER-SHOCKWAVE-FLASH"
3928 >+filter{shockwave-flash} # Kill embedded Shockwave Flash objects.</PRE
3936 NAME="FILTER-QUICKTIME-KIOSKMODE"
3947 >+filter{quicktime-kioskmode} # Make Quicktime movies saveable.</PRE
3966 >+filter{fun} # Text replacements for subversive browsing fun!</PRE
3974 NAME="FILTER-CRUDE-PARENTAL"
3985 >+filter{crude-parental} # Crude parental filtering. Note that this filter doesn't work reliably.</PRE
3993 NAME="FILTER-IE-EXPLOITS"
4004 >+filter{ie-exploits} # Disable some known Internet Explorer bug exploits.</PRE
4012 NAME="FILTER-SITE-SPECIFICS"
4023 >+filter{site-specifics} # Cure for site-specific problems. Don't apply generally!</PRE
4031 NAME="FILTER-NO-PING"
4042 >+filter{no-ping} # Removes non-standard ping attributes in <a> and <area> tags.</PRE
4050 NAME="FILTER-GOOGLE"
4061 >+filter{google} # CSS-based block for Google text ads. Also removes a width limitation and the toolbar advertisement.</PRE
4080 >+filter{yahoo} # CSS-based block for Yahoo text ads. Also removes a width limitation.</PRE
4099 >+filter{msn} # CSS-based block for MSN text ads. Also removes tracking URLs and a width limitation.</PRE
4107 NAME="FILTER-BLOGSPOT"
4118 >+filter{blogspot} # Cleans up some Blogspot blogs. Read the fine print before using this.</PRE
4133 NAME="FORCE-TEXT-MODE"
4134 >8.5.16. force-text-mode</A
4139 CLASS="VARIABLELIST"
4148 > to treat a document as if it was in some kind of <SPAN
4160 > Declares a document as text, even if the <SPAN
4162 >"Content-Type:"</SPAN
4163 > isn't detected as such.
4186 HREF="actions-file.html#FILTER"
4193 > tries to only filter files that are
4194 in some kind of text format. The same restrictions apply to
4198 HREF="actions-file.html#CONTENT-TYPE-OVERWRITE"
4199 >content-type-overwrite</A
4204 >force-text-mode</TT
4205 > declares a document as text,
4206 without looking at the <SPAN
4208 >"Content-Type:"</SPAN
4230 > Think twice before activating this action. Filtering binary data
4231 with regular expressions can cause file damage.
4266 NAME="FORWARD-OVERRIDE"
4267 >8.5.17. forward-override</A
4272 CLASS="VARIABLELIST"
4278 >Change the forwarding settings based on User-Agent or request origin</P
4284 > Overrules the forward directives in the configuration file.
4304 > to use a direct connection without any additional proxies.</P
4310 >"forward 127.0.0.1:8123"</SPAN
4311 > to use the HTTP proxy listening at 127.0.0.1 port 8123.
4318 >"forward-socks4a 127.0.0.1:9050 ."</SPAN
4319 > to use the socks4a proxy listening at
4320 127.0.0.1 port 9050. Replace <SPAN
4322 >"forward-socks4a"</SPAN
4325 >"forward-socks4"</SPAN
4327 to use a socks4 connection (with local DNS resolution) instead, use <SPAN
4329 >"forward-socks5"</SPAN
4331 for socks5 connections (with remote DNS resolution).
4338 >"forward-socks4a 127.0.0.1:9050 proxy.example.org:8000"</SPAN
4339 > to use the socks4a proxy
4340 listening at 127.0.0.1 port 9050 to reach the HTTP proxy listening at proxy.example.org port 8000.
4343 >"forward-socks4a"</SPAN
4346 >"forward-socks4"</SPAN
4347 > to use a socks4 connection
4348 (with local DNS resolution) instead, use <SPAN
4350 >"forward-socks5"</SPAN
4352 for socks5 connections (with remote DNS resolution).
4361 > This action takes parameters similar to the
4363 HREF="config.html#FORWARDING"
4365 > directives in the configuration
4366 file, but without the URL pattern. It can be used as replacement, but normally it's only
4367 used in cases where matching based on the request URL isn't sufficient.
4388 > Please read the description for the <A
4389 HREF="config.html#FORWARDING"
4392 using this action. Forwarding to the wrong people will reduce your privacy and increase the
4393 chances of man-in-the-middle attacks.
4396 > If the ports are missing or invalid, default values will be used. This might change
4397 in the future and you shouldn't rely on it. Otherwise incorrect syntax causes Privoxy
4402 HREF="http://config.privoxy.org/show-url-info"
4404 >show-url-info CGI page</A
4406 to verify that your forward settings do what you thought the do.
4425 ># Always use direct connections for requests previously tagged as
4428 >"User-Agent: fetch libfetch/2.0"</SPAN
4430 # resuming downloads continues to work.
4431 # This way you can continue to use Tor for your normal browsing,
4432 # without overloading the Tor network with your FreeBSD ports updates
4433 # or downloads of bigger files like ISOs.
4434 # Note that HTTP headers are easy to fake and therefore their
4435 # values are as (un)trustworthy as your clients and users.
4436 {+forward-override{forward .} \
4437 -hide-if-modified-since \
4438 -overwrite-last-modified \
4440 TAG:^User-Agent: fetch libfetch/2\.0$
4456 NAME="HANDLE-AS-EMPTY-DOCUMENT"
4457 >8.5.18. handle-as-empty-document</A
4462 CLASS="VARIABLELIST"
4468 >Mark URLs that should be replaced by empty documents <SPAN
4472 >if they get blocked</I
4480 > This action alone doesn't do anything noticeable. It just marks URLs.
4484 HREF="actions-file.html#BLOCK"
4494 the presence or absence of this mark decides whether an HTML <SPAN
4498 page, or an empty document will be sent to the client as a substitute for the blocked content.
4505 > document isn't literally empty, but actually contains a single space.
4525 > Some browsers complain about syntax errors if JavaScript documents
4526 are blocked with <SPAN
4530 default HTML page; this option can be used to silence them.
4531 And of course this action can also be used to eliminate the <SPAN
4535 BLOCKED message in frames.
4538 > The content type for the empty document can be specified with
4542 HREF="actions-file.html#CONTENT-TYPE-OVERWRITE"
4543 >content-type-overwrite{}</A
4546 but usually this isn't necessary.
4561 ># Block all documents on example.org that end with ".js",
4562 # but send an empty document instead of the usual HTML message.
4563 {+block{Blocked JavaScript} +handle-as-empty-document}
4580 NAME="HANDLE-AS-IMAGE"
4581 >8.5.19. handle-as-image</A
4586 CLASS="VARIABLELIST"
4592 >Mark URLs as belonging to images (so they'll be replaced by images <SPAN
4596 >if they do get blocked</I
4598 >, rather than HTML pages)</P
4604 > This action alone doesn't do anything noticeable. It just marks URLs as images.
4608 HREF="actions-file.html#BLOCK"
4618 the presence or absence of this mark decides whether an HTML <SPAN
4622 page, or a replacement image (as determined by the <TT
4625 HREF="actions-file.html#SET-IMAGE-BLOCKER"
4626 >set-image-blocker</A
4628 > action) will be sent to the
4629 client as a substitute for the blocked content.
4649 > The below generic example section is actually part of <TT
4653 It marks all URLs with well-known image file name extensions as images and should
4657 > Users will probably only want to use the handle-as-image action in conjunction with
4661 HREF="actions-file.html#BLOCK"
4664 >, to block sources of banners, whose URLs don't
4665 reflect the file type, like in the second example section.
4668 > Note that you cannot treat HTML pages as images in most cases. For instance, (in-line) ad
4669 frames require an HTML page to be sent, or they won't display properly.
4672 >handle-as-image</TT
4673 > in this situation will not replace the
4674 ad frame with an image, but lead to error messages.
4678 >Example usage (sections):</DT
4689 ># Generic image extensions:
4692 /.*\.(gif|jpg|jpeg|png|bmp|ico)$
4694 # These don't look like images, but they're banners and should be
4695 # blocked as images:
4697 {+block{Nasty banners.} +handle-as-image}
4698 nasty-banner-server.example.com/junk.cgi\?output=trash</PRE
4713 NAME="HIDE-ACCEPT-LANGUAGE"
4714 >8.5.20. hide-accept-language</A
4719 CLASS="VARIABLELIST"
4725 >Pretend to use different language settings.</P
4731 > Deletes or replaces the <SPAN
4733 >"Accept-Language:"</SPAN
4734 > HTTP header in client requests.
4750 >, or any user defined value.
4757 > Faking the browser's language settings can be useful to make a
4758 foreign User-Agent set with
4762 HREF="actions-file.html#HIDE-USER-AGENT"
4769 > However some sites with content in different languages check the
4772 >"Accept-Language:"</SPAN
4773 > to decide which one to take by default.
4774 Sometimes it isn't possible to later switch to another language without
4777 >"Accept-Language:"</SPAN
4781 > Therefore it's a good idea to either only change the
4784 >"Accept-Language:"</SPAN
4785 > header to languages you understand,
4786 or to languages that aren't wide spread.
4789 > Before setting the <SPAN
4791 >"Accept-Language:"</SPAN
4793 to a rare language, you should consider that it helps to
4794 make your requests unique and thus easier to trace.
4795 If you don't plan to change this header frequently,
4796 you should stick to a common language.
4800 >Example usage (section):</DT
4811 ># Pretend to use Canadian language settings.
4812 {+hide-accept-language{en-ca} \
4813 +hide-user-agent{Mozilla/5.0 (X11; U; OpenBSD i386; en-CA; rv:1.8.0.4) Gecko/20060628 Firefox/1.5.0.4} \
4830 NAME="HIDE-CONTENT-DISPOSITION"
4831 >8.5.21. hide-content-disposition</A
4836 CLASS="VARIABLELIST"
4842 >Prevent download menus for content you prefer to view inside the browser.</P
4848 > Deletes or replaces the <SPAN
4850 >"Content-Disposition:"</SPAN
4851 > HTTP header set by some servers.
4867 >, or any user defined value.
4874 > Some servers set the <SPAN
4876 >"Content-Disposition:"</SPAN
4878 documents they assume you want to save locally before viewing them.
4881 >"Content-Disposition:"</SPAN
4882 > header contains the file name
4883 the browser is supposed to use by default.
4886 > In most browsers that understand this header, it makes it impossible to
4893 > the document, without downloading it first,
4894 even if it's just a simple text file or an image.
4897 > Removing the <SPAN
4899 >"Content-Disposition:"</SPAN
4901 to prevent this annoyance, but some browsers additionally check the
4904 >"Content-Type:"</SPAN
4905 > header, before they decide if they can
4906 display a document without saving it first. In these cases, you have
4907 to change this header as well, before the browser stops displaying
4911 > It is also possible to change the server's file name suggestion
4912 to another one, but in most cases it isn't worth the time to set
4916 > This action will probably be removed in the future,
4917 use server-header filters instead.
4932 ># Disarm the download link in Sourceforge's patch tracker
4934 +content-type-overwrite{text/plain}\
4935 +hide-content-disposition{block} }
4936 .sourceforge.net/tracker/download\.php</PRE
4951 NAME="HIDE-IF-MODIFIED-SINCE"
4952 >8.5.22. hide-if-modified-since</A
4957 CLASS="VARIABLELIST"
4963 >Prevent yet another way to track the user's steps between sessions.</P
4971 >"If-Modified-Since:"</SPAN
4972 > HTTP client header or modifies its value.
4988 >, or a user defined value that specifies a range of hours.
4995 > Removing this header is useful for filter testing, where you want to force a real
4996 reload instead of getting status code <SPAN
4999 >, which would cause the
5000 browser to use a cached copy of the page.
5003 > Instead of removing the header, <TT
5005 >hide-if-modified-since</TT
5007 also add or subtract a random amount of time to/from the header's value.
5008 You specify a range of minutes where the random factor should be chosen from and
5012 > does the rest. A negative value means
5013 subtracting, a positive value adding.
5016 > Randomizing the value of the <SPAN
5018 >"If-Modified-Since:"</SPAN
5020 it less likely that the server can use the time as a cookie replacement,
5021 but you will run into caching problems if the random range is too high.
5024 > It is a good idea to only use a small negative value and let
5028 HREF="actions-file.html#OVERWRITE-LAST-MODIFIED"
5029 >overwrite-last-modified</A
5032 handle the greater changes.
5035 > It is also recommended to use this action together with
5039 HREF="actions-file.html#CRUNCH-IF-NONE-MATCH"
5040 >crunch-if-none-match</A
5043 otherwise it's more or less pointless.
5047 >Example usage (section):</DT
5058 ># Let the browser revalidate but make tracking based on the time less likely.
5059 {+hide-if-modified-since{-60} \
5060 +overwrite-last-modified{randomize} \
5061 +crunch-if-none-match}
5077 NAME="HIDE-FROM-HEADER"
5078 >8.5.23. hide-from-header</A
5083 CLASS="VARIABLELIST"
5089 >Keep your (old and ill) browser from telling web servers your email address</P
5095 > Deletes any existing <SPAN
5098 > HTTP header, or replaces it with the
5115 >, or any user defined value.
5125 > will completely remove the header
5126 (not to be confused with the <TT
5129 HREF="actions-file.html#BLOCK"
5136 > Alternately, you can specify any value you prefer to be sent to the web
5137 server. If you do, it is a matter of fairness not to use any address that
5138 is actually used by a real person.
5141 > This action is rarely needed, as modern web browsers don't send
5160 >+hide-from-header{block}</PRE
5173 >+hide-from-header{spam-me-senseless@sittingduck.example.com}</PRE
5188 NAME="HIDE-REFERRER"
5189 >8.5.24. hide-referrer</A
5197 CLASS="VARIABLELIST"
5203 >Conceal which link you followed to get to a particular site</P
5212 > (sic) HTTP header from the client request,
5213 or replaces it with a forged one.
5232 >"conditional-block"</SPAN
5233 > to delete the header completely if the host has changed.</P
5239 >"conditional-forge"</SPAN
5240 > to forge the header if the host has changed.</P
5247 > to delete the header unconditionally.</P
5254 > to pretend to be coming from the homepage of the server we are talking to.</P
5258 >Any other string to set a user defined referrer.</P
5268 >conditional-block</TT
5269 > is the only parameter,
5270 that isn't easily detected in the server's log file. If it blocks the
5271 referrer, the request will look like the visitor used a bookmark or
5272 typed in the address directly.
5275 > Leaving the referrer unmodified for requests on the same host
5276 allows the server owner to see the visitor's <SPAN
5280 but in most cases she could also get that information by comparing
5281 other parts of the log file: for example the User-Agent if it isn't
5282 a very common one, or the user's IP address if it doesn't change between
5286 > Always blocking the referrer, or using a custom one, can lead to
5287 failures on servers that check the referrer before they answer any
5288 requests, in an attempt to prevent their content from being
5289 embedded or linked to elsewhere.
5294 >conditional-block</TT
5299 will work with referrer checks, as long as content and valid referring page
5300 are on the same host. Most of the time that's the case.
5307 > is an alternate spelling of
5311 > and the two can be can be freely
5312 substituted with each other. (<SPAN
5316 correct English spelling, however the HTTP specification has a bug - it
5317 requires it to be spelled as <SPAN
5335 >+hide-referrer{forge}</PRE
5348 >+hide-referrer{http://www.yahoo.com/}</PRE
5363 NAME="HIDE-USER-AGENT"
5364 >8.5.25. hide-user-agent</A
5369 CLASS="VARIABLELIST"
5375 >Try to conceal your type of browser and client operating system</P
5381 > Replaces the value of the <SPAN
5383 >"User-Agent:"</SPAN
5385 in client requests with the specified value.
5398 > Any user-defined string.
5423 > This can lead to problems on web sites that depend on looking at this header in
5424 order to customize their content for different browsers (which, by the
5431 > the right thing to do: good web sites
5432 work browser-independently).
5439 > Using this action in multi-user setups or wherever different types of
5440 browsers will access the same <SPAN
5450 >. In single-user, single-browser
5451 setups, you might use it to delete your OS version information from
5452 the headers, because it is an invitation to exploit known bugs for your
5453 OS. It is also occasionally useful to forge this in order to access
5454 sites that won't let you in otherwise (though there may be a good
5455 reason in some cases). Example of this: some MSN sites will not
5459 > enter, yet forging to a
5463 > user-agent works just fine.
5464 (Must be just a silly MS goof, I'm sure :-).
5467 > More information on known user-agent strings can be found at
5469 HREF="http://www.user-agents.org/"
5471 >http://www.user-agents.org/</A
5475 HREF="http://en.wikipedia.org/wiki/User_agent"
5477 >http://en.wikipedia.org/wiki/User_agent</A
5493 >+hide-user-agent{Netscape 6.1 (X11; I; Linux 2.4.18 i686)}</PRE
5508 NAME="LIMIT-CONNECT"
5509 >8.5.26. limit-connect</A
5514 CLASS="VARIABLELIST"
5520 >Prevent abuse of <SPAN
5523 > as a TCP proxy relay or disable SSL for untrusted sites</P
5529 > Specifies to which ports HTTP CONNECT requests are allowable.
5542 > A comma-separated list of ports or port ranges (the latter using dashes, with the minimum
5543 defaulting to 0 and the maximum to 65K).
5550 > By default, i.e. if no <TT
5557 > allows HTTP CONNECT requests to all
5561 > if fine-grained control
5562 is desired for some or all destinations.
5565 > The CONNECT methods exists in HTTP to allow access to secure websites
5569 > URLs) through proxies. It works very simply:
5570 the proxy connects to the server on the specified port, and then
5571 short-circuits its connections to the client and to the remote server.
5572 This means CONNECT-enabled proxies can be used as TCP relays very easily.
5578 > relays HTTPS traffic without seeing
5579 the decoded content. Websites can leverage this limitation to circumvent <SPAN
5583 filters. By specifying an invalid port range you can disable HTTPS entirely.
5587 >Example usages:</DT
5598 >+limit-connect{443} # Port 443 is OK.
5599 +limit-connect{80,443} # Ports 80 and 443 are OK.
5600 +limit-connect{-3, 7, 20-100, 500-} # Ports less than 3, 7, 20 to 100 and above 500 are OK.
5601 +limit-connect{-} # All ports are OK
5602 +limit-connect{,} # No HTTPS/SSL traffic is allowed</PRE
5617 NAME="PREVENT-COMPRESSION"
5618 >8.5.27. prevent-compression</A
5623 CLASS="VARIABLELIST"
5629 > Ensure that servers send the content uncompressed, so it can be
5633 HREF="actions-file.html#FILTER"
5643 > Removes the Accept-Encoding header which can be used to ask for compressed transfer.
5663 > More and more websites send their content compressed by default, which
5664 is generally a good idea and saves bandwidth. But the <TT
5667 HREF="actions-file.html#FILTER"
5674 HREF="actions-file.html#DEANIMATE-GIFS"
5678 actions need access to the uncompressed data.
5681 > When compiled with zlib support (available since <SPAN
5684 > 3.0.7), content that should be
5685 filtered is decompressed on-the-fly and you don't have to worry about this action.
5686 If you are using an older <SPAN
5689 > version, or one that hasn't been compiled with zlib
5690 support, this action can be used to convince the server to send the content uncompressed.
5693 > Most text-based instances compress very well, the size is seldom decreased by less than 50%,
5694 for markup-heavy instances like news feeds saving more than 90% of the original size isn't
5698 > Not using compression will therefore slow down the transfer, and you should only
5699 enable this action if you really need it. As of <SPAN
5702 > 3.0.7 it's disabled in all
5703 predefined action settings.
5706 > Note that some (rare) ill-configured sites don't handle requests for uncompressed
5707 documents correctly. Broken PHP applications tend to send an empty document body,
5708 some IIS versions only send the beginning of the content. If you enable
5711 >prevent-compression</TT
5712 > per default, you might want to add
5713 exceptions for those sites. See the example for how to do that.
5717 >Example usage (sections):</DT
5728 ># Selectively turn off compression, and enable a filter
5730 { +filter{tiny-textforms} +prevent-compression }
5731 # Match only these sites
5736 # Or instead, we could set a universal default:
5738 { +prevent-compression }
5741 # Then maybe make exceptions for broken sites:
5743 { -prevent-compression }
5759 NAME="OVERWRITE-LAST-MODIFIED"
5760 >8.5.28. overwrite-last-modified</A
5765 CLASS="VARIABLELIST"
5771 >Prevent yet another way to track the user's steps between sessions.</P
5779 >"Last-Modified:"</SPAN
5780 > HTTP server header or modifies its value.
5793 > One of the keywords: <SPAN
5798 >"reset-to-request-time"</SPAN
5810 > Removing the <SPAN
5812 >"Last-Modified:"</SPAN
5813 > header is useful for filter
5814 testing, where you want to force a real reload instead of getting status
5818 >, which would cause the browser to reuse the old
5819 version of the page.
5825 > option overwrites the value of the
5828 >"Last-Modified:"</SPAN
5829 > header with a randomly chosen time
5830 between the original value and the current time. In theory the server
5831 could send each document with a different <SPAN
5833 >"Last-Modified:"</SPAN
5835 header to track visits without using cookies. <SPAN
5839 makes it impossible and the browser can still revalidate cached documents.
5844 >"reset-to-request-time"</SPAN
5845 > overwrites the value of the
5848 >"Last-Modified:"</SPAN
5849 > header with the current time. You could use
5850 this option together with
5854 HREF="actions-file.html#HIDE-IF-MODIFIED-SINCE"
5855 >hided-if-modified-since</A
5858 to further customize your random range.
5861 > The preferred parameter here is <SPAN
5865 to use, as long as the time settings are more or less correct.
5866 If the server sets the <SPAN
5868 >"Last-Modified:"</SPAN
5869 > header to the time
5870 of the request, the random range becomes zero and the value stays the same.
5871 Therefore you should later randomize it a second time with
5875 HREF="actions-file.html#HIDE-IF-MODIFIED-SINCE"
5876 >hided-if-modified-since</A
5882 > It is also recommended to use this action together with
5886 HREF="actions-file.html#CRUNCH-IF-NONE-MATCH"
5887 >crunch-if-none-match</A
5904 ># Let the browser revalidate without being tracked across sessions
5905 { +hide-if-modified-since{-60} \
5906 +overwrite-last-modified{randomize} \
5907 +crunch-if-none-match}
5924 >8.5.29. redirect</A
5929 CLASS="VARIABLELIST"
5935 > Redirect requests to other sites.
5942 > Convinces the browser that the requested document has been moved
5943 to another location and the browser should get it from there.
5956 > An absolute URL or a single pcrs command.
5963 > Requests to which this action applies are answered with a
5964 HTTP redirect to URLs of your choosing. The new URL is
5965 either provided as parameter, or derived by applying a
5966 single pcrs command to the original URL.
5969 > This action will be ignored if you use it together with
5973 HREF="actions-file.html#BLOCK"
5977 It can be combined with
5981 HREF="actions-file.html#FAST-REDIRECTS"
5982 >fast-redirects{check-decoded-url}</A
5985 to redirect to a decoded version of a rewritten URL.
5988 > Use this action carefully, make sure not to create redirection loops
5989 and be aware that using your own redirects might make it
5990 possible to fingerprint your requests.
5993 > In case of problems with your redirects, or simply to watch
5994 them working, enable <A
5995 HREF="config.html#DEBUG"
6001 >Example usages:</DT
6012 ># Replace example.com's style sheet with another one
6013 { +redirect{http://localhost/css-replacements/example.com.css} }
6014 example.com/stylesheet\.css
6016 # Create a short, easy to remember nickname for a favorite site
6017 # (relies on the browser accept and forward invalid URLs to <SPAN
6021 { +redirect{http://www.privoxy.org/user-manual/actions-file.html} }
6024 # Always use the expanded view for Undeadly.org articles
6025 # (Note the $ at the end of the URL pattern to make sure
6026 # the request for the rewritten URL isn't redirected as well)
6027 {+redirect{s@$@&mode=expanded@}}
6028 undeadly.org/cgi\?action=article&sid=\d*$
6030 # Redirect Google search requests to MSN
6031 {+redirect{s@^http://[^/]*/search\?q=([^&]*).*@http://search.msn.com/results.aspx?q=$1@}}
6034 # Redirect MSN search requests to Yahoo
6035 {+redirect{s@^http://[^/]*/results\.aspx\?q=([^&]*).*@http://search.yahoo.com/search?p=$1@}}
6036 search.msn.com//results\.aspx\?q=
6038 # Redirect remote requests for this manual
6039 # to the local version delivered by Privoxy
6040 {+redirect{s@^http://www@http://config@}}
6041 www.privoxy.org/user-manual/</PRE
6056 NAME="SERVER-HEADER-FILTER"
6057 >8.5.30. server-header-filter</A
6062 CLASS="VARIABLELIST"
6068 > Rewrite or remove single server headers.
6075 > All server headers to which this action applies are filtered on-the-fly
6076 through the specified regular expression based substitutions.
6089 > The name of a server-header filter, as defined in one of the
6091 HREF="filter-file.html"
6100 > Server-header filters are applied to each header on its own, not to
6101 all at once. This makes it easier to diagnose problems, but on the downside
6102 you can't write filters that only change header x if header y's value is z.
6103 You can do that by using tags though.
6106 > Server-header filters are executed after the other header actions have finished
6107 and use their output as input.
6110 > Please refer to the <A
6111 HREF="filter-file.html"
6112 >filter file chapter</A
6114 to learn which server-header filters are available by default, and how to
6119 >Example usage (section):</DT
6130 >{+server-header-filter{html-to-xml}}
6131 example.org/xml-instance-that-is-delivered-as-html
6133 {+server-header-filter{xml-to-html}}
6134 example.org/instance-that-is-delivered-as-xml-but-is-not
6150 NAME="SERVER-HEADER-TAGGER"
6151 >8.5.31. server-header-tagger</A
6156 CLASS="VARIABLELIST"
6162 > Enable or disable filters based on the Content-Type header.
6169 > Server headers to which this action applies are filtered on-the-fly through
6170 the specified regular expression based substitutions, the result is used as
6184 > The name of a server-header tagger, as defined in one of the
6186 HREF="filter-file.html"
6195 > Server-header taggers are applied to each header on its own,
6196 and as the header isn't modified, each tagger <SPAN
6203 > Server-header taggers are executed before all other header actions
6204 that modify server headers. Their tags can be used to control
6205 all of the other server-header actions, the content filters
6206 and the crunch actions (<A
6207 HREF="actions-file.html#REDIRECT"
6211 HREF="actions-file.html#BLOCK"
6216 > Obviously crunching based on tags created by server-header taggers
6217 doesn't prevent the request from showing up in the server's log file.
6221 >Example usage (section):</DT
6232 ># Tag every request with the content type declared by the server
6233 {+server-header-tagger{content-type}}
6250 NAME="SESSION-COOKIES-ONLY"
6251 >8.5.32. session-cookies-only</A
6256 CLASS="VARIABLELIST"
6262 > Allow only temporary <SPAN
6265 > cookies (for the current
6266 browser session <SPAN
6284 >"Set-Cookie:"</SPAN
6286 server headers. Most browsers will not store such cookies permanently and
6287 forget them in between sessions.
6307 > This is less strict than <TT
6310 HREF="actions-file.html#CRUNCH-INCOMING-COOKIES"
6311 >crunch-incoming-cookies</A
6317 HREF="actions-file.html#CRUNCH-OUTGOING-COOKIES"
6318 >crunch-outgoing-cookies</A
6320 > and allows you to browse
6321 websites that insist or rely on setting cookies, without compromising your privacy too badly.
6324 > Most browsers will not permanently store cookies that have been processed by
6327 >session-cookies-only</TT
6328 > and will forget about them between sessions.
6329 This makes profiling cookies useless, but won't break sites which require cookies so
6330 that you can log in for transactions. This is generally turned on for all
6331 sites, and is the recommended setting.
6342 >session-cookies-only</TT
6347 HREF="actions-file.html#CRUNCH-INCOMING-COOKIES"
6348 >crunch-incoming-cookies</A
6354 HREF="actions-file.html#CRUNCH-OUTGOING-COOKIES"
6355 >crunch-outgoing-cookies</A
6357 >. If you do, cookies
6358 will be plainly killed.
6361 > Note that it is up to the browser how it handles such cookies without an <SPAN
6365 field. If you use an exotic browser, you might want to try it out to be sure.
6368 > This setting also has no effect on cookies that may have been stored
6369 previously by the browser before starting <SPAN
6373 These would have to be removed manually.
6381 HREF="actions-file.html#FILTER-CONTENT-COOKIES"
6382 >content-cookies filter</A
6384 to block some types of cookies. Content cookies are not effected by
6387 >session-cookies-only</TT
6403 >+session-cookies-only</PRE
6418 NAME="SET-IMAGE-BLOCKER"
6419 >8.5.33. set-image-blocker</A
6424 CLASS="VARIABLELIST"
6430 >Choose the replacement for blocked images</P
6436 > This action alone doesn't do anything noticeable. If <SPAN
6446 HREF="actions-file.html#BLOCK"
6458 HREF="actions-file.html#HANDLE-AS-IMAGE"
6468 apply, i.e. if the request is to be blocked as an image,
6475 > the parameter of this action decides what will be
6476 sent as a replacement.
6496 > to send a built-in checkerboard pattern image. The image is visually
6497 decent, scales very well, and makes it obvious where banners were busted.
6505 > to send a built-in transparent image. This makes banners disappear
6506 completely, but makes it hard to detect where <SPAN
6510 images on a given page and complicates troubleshooting if <SPAN
6514 has blocked innocent images, like navigation icons.
6528 send a redirect to <TT
6534 to any image anywhere, even in your local filesystem via <SPAN
6538 (But note that not all browsers support redirecting to a local file system).
6541 > A good application of redirects is to use special <SPAN
6545 URLs, which send the built-in images, as <TT
6551 This has the same visual effect as specifying <SPAN
6558 the first place, but enables your browser to cache the replacement image, instead of requesting
6559 it over and over again.
6568 > The URLs for the built-in images are <SPAN
6570 >"http://config.privoxy.org/send-banner?type=<TT
6591 > There is a third (advanced) type, called <SPAN
6603 >set-image-blocker</TT
6604 >, but meant for use from <A
6605 HREF="filter-file.html"
6608 Auto will select the type of image that would have applied to the referring page, had it been an image.
6626 >+set-image-blocker{pattern}</PRE
6633 > Redirect to the BSD daemon:
6644 >+set-image-blocker{http://www.freebsd.org/gifs/dae_up3.gif}</PRE
6651 > Redirect to the built-in pattern for better caching:
6662 >+set-image-blocker{http://config.privoxy.org/send-banner?type=pattern}</PRE
6681 > Note that many of these actions have the potential to cause a page to
6682 misbehave, possibly even not to display at all. There are many ways
6683 a site designer may choose to design his site, and what HTTP header
6684 content, and other criteria, he may depend on. There is no way to have hard
6685 and fast rules for all sites. See the <A
6686 HREF="appendix.html#ACTIONSANAT"
6688 > for a brief example on troubleshooting
6711 >, can be defined by combining other actions.
6712 These can in turn be invoked just like the built-in actions.
6713 Currently, an alias name can contain any character except space, tab,
6731 > that you only use <SPAN
6751 Alias names are not case sensitive, and are not required to start with a
6758 > sign, since they are merely textually
6761 > Aliases can be used throughout the actions file, but they <SPAN
6766 defined in a special section at the top of the file!</I
6769 And there can only be one such section per actions file. Each actions file may
6770 have its own alias section, and the aliases defined in it are only visible
6771 within that file.</P
6773 > There are two main reasons to use aliases: One is to save typing for frequently
6774 used combinations of actions, the other one is a gain in flexibility: If you
6775 decide once how you want to handle shops by defining an alias called
6779 >, you can later change your policy on shops in
6786 > place, and your changes will take effect everywhere
6787 in the actions file where the <SPAN
6790 > alias is used. Calling aliases
6791 by their purpose also makes your actions files more readable.</P
6793 > Currently, there is one big drawback to using aliases, though:
6797 >'s built-in web-based action file
6798 editor honors aliases when reading the actions files, but it expands
6799 them before writing. So the effects of your aliases are of course preserved,
6800 but the aliases themselves are lost when you edit sections that use aliases
6803 > Now let's define some aliases...</P
6813 > # Useful custom aliases we can use later.
6815 # Note the (required!) section header line and that this section
6816 # must be at the top of the actions file!
6820 # These aliases just save typing later:
6821 # (Note that some already use other aliases!)
6823 +crunch-all-cookies = +<A
6824 HREF="actions-file.html#CRUNCH-INCOMING-COOKIES"
6825 >crunch-incoming-cookies</A
6827 HREF="actions-file.html#CRUNCH-OUTGOING-COOKIES"
6828 >crunch-outgoing-cookies</A
6830 -crunch-all-cookies = -<A
6831 HREF="actions-file.html#CRUNCH-INCOMING-COOKIES"
6832 >crunch-incoming-cookies</A
6834 HREF="actions-file.html#CRUNCH-OUTGOING-COOKIES"
6835 >crunch-outgoing-cookies</A
6837 +block-as-image = +block{Blocked image.} +handle-as-image
6838 allow-all-cookies = -crunch-all-cookies -<A
6839 HREF="actions-file.html#SESSION-COOKIES-ONLY"
6840 >session-cookies-only</A
6842 HREF="actions-file.html#FILTER-CONTENT-COOKIES"
6843 >filter{content-cookies}</A
6846 # These aliases define combinations of actions
6847 # that are useful for certain types of sites:
6850 HREF="actions-file.html#BLOCK"
6853 HREF="actions-file.html#FILTER"
6855 > -crunch-all-cookies -<A
6856 HREF="actions-file.html#FAST-REDIRECTS"
6859 HREF="actions-file.html#HIDE-REFERER"
6862 HREF="actions-file.html#PREVENT-COMPRESSION"
6863 >prevent-compression</A
6866 shop = -crunch-all-cookies -<A
6867 HREF="actions-file.html#FILTER-ALL-POPUPS"
6868 >filter{all-popups}</A
6871 # Short names for other aliases, for really lazy people ;-)
6873 c0 = +crunch-all-cookies
6874 c1 = -crunch-all-cookies</PRE
6880 > ...and put them to use. These sections would appear in the lower part of an
6881 actions file and define exceptions to the default actions (as specified further
6895 > # These sites are either very complex or very keen on
6896 # user data and require minimal interference to work:
6899 .office.microsoft.com
6900 .windowsupdate.microsoft.com
6901 # Gmail is really mail.google.com, not gmail.com
6905 # Allow cookies (for setting and retrieving your customer data)
6909 .worldpay.com # for quietpc.com
6912 # These shops require pop-ups:
6914 {-filter{all-popups} -filter{unsolicited-popups}}
6916 .overclockers.co.uk</PRE
6922 > Aliases like <SPAN
6928 > are typically used for
6932 > sites that require more than one action to be disabled
6933 in order to function properly.</P
6941 >8.7. Actions Files Tutorial</A
6944 > The above chapters have shown <A
6945 HREF="actions-file.html"
6946 >which actions files
6947 there are and how they are organized</A
6948 >, how actions are <A
6949 HREF="actions-file.html#ACTIONS"
6952 HREF="actions-file.html#ACTIONS-APPLY"
6956 HREF="actions-file.html#AF-PATTERNS"
6960 HREF="actions-file.html#ALIASES"
6962 >. Now, let's look at an
6965 >match-all.action</TT
6973 > file and see how all these pieces come together:</P
6980 >8.7.1. match-all.action</A
6987 >all actions are disabled when matching starts</I
6990 so we have to explicitly enable the ones we want.</P
6994 >match-all.action</TT
6995 > file only contains a
6996 single section, it is probably the most important one. It has only one
7005 HREF="actions-file.html#AF-PATTERNS"
7006 >matches all URLs</A
7007 >. Therefore, the set of
7008 actions used in this <SPAN
7016 be applied to all requests as a start</I
7018 >. It can be partly or
7019 wholly overridden by other actions files like <TT
7026 >, but it will still be largely responsible
7027 for your overall browsing experience.</P
7029 > Again, at the start of matching, all actions are disabled, so there is
7030 no need to disable any actions here. (Remember: a <SPAN
7034 preceding the action name enables the action, a <SPAN
7038 Also note how this long line has been made more readable by splitting it into
7039 multiple lines with line continuation.</P
7051 HREF="actions-file.html#CHANGE-X-FORWARDED-FOR"
7052 >change-x-forwarded-for{block}</A
7055 HREF="actions-file.html#HIDE-FROM-HEADER"
7056 >hide-from-header{block}</A
7059 HREF="actions-file.html#SET-IMAGE-BLOCKER"
7060 >set-image-blocker{pattern}</A
7070 > The default behavior is now set.</P
7078 >8.7.2. default.action</A
7081 > If you aren't a developer, there's no need for you to edit the
7085 > file. It is maintained by
7089 > developers and if you disagree with some of the
7090 sections, you should overrule them in your <TT
7095 > Understanding the <TT
7099 help you with your <TT
7104 > The first section in this file is a special section for internal use
7105 that prevents older <SPAN
7108 > versions from reading the file:</P
7118 >##########################################################################
7119 # Settings -- Don't change! For internal Privoxy use ONLY.
7120 ##########################################################################
7122 for-privoxy-version=3.0.11</PRE
7128 > After that comes the (optional) alias section. We'll use the example
7129 section from the above <A
7130 HREF="actions-file.html#ALIASES"
7131 >chapter on aliases</A
7133 that also explains why and how aliases are used:</P
7143 >##########################################################################
7145 ##########################################################################
7148 # These aliases just save typing later:
7149 # (Note that some already use other aliases!)
7151 +crunch-all-cookies = +<A
7152 HREF="actions-file.html#CRUNCH-INCOMING-COOKIES"
7153 >crunch-incoming-cookies</A
7155 HREF="actions-file.html#CRUNCH-OUTGOING-COOKIES"
7156 >crunch-outgoing-cookies</A
7158 -crunch-all-cookies = -<A
7159 HREF="actions-file.html#CRUNCH-INCOMING-COOKIES"
7160 >crunch-incoming-cookies</A
7162 HREF="actions-file.html#CRUNCH-OUTGOING-COOKIES"
7163 >crunch-outgoing-cookies</A
7165 +block-as-image = +block{Blocked image.} +handle-as-image
7166 mercy-for-cookies = -crunch-all-cookies -<A
7167 HREF="actions-file.html#SESSION-COOKIES-ONLY"
7168 >session-cookies-only</A
7170 HREF="actions-file.html#FILTER-CONTENT-COOKIES"
7171 >filter{content-cookies}</A
7174 # These aliases define combinations of actions
7175 # that are useful for certain types of sites:
7178 HREF="actions-file.html#BLOCK"
7181 HREF="actions-file.html#FILTER"
7183 > -crunch-all-cookies -<A
7184 HREF="actions-file.html#FAST-REDIRECTS"
7187 HREF="actions-file.html#HIDE-REFERER"
7190 shop = -crunch-all-cookies -<A
7191 HREF="actions-file.html#FILTER-ALL-POPUPS"
7192 >filter{all-popups}</A
7199 > The first of our specialized sections is concerned with <SPAN
7203 sites, i.e. sites that require minimum interference, because they are either
7204 very complex or very keen on tracking you (and have mechanisms in place that
7205 make them unusable for people who avoid being tracked). We will simply use
7209 > alias instead of stating the list
7210 of actions explicitly:</P
7220 >##########################################################################
7221 # Exceptions for sites that'll break under the default action set:
7222 ##########################################################################
7224 # "Fragile" Use a minimum set of actions for these sites (see alias above):
7227 .office.microsoft.com # surprise, surprise!
7228 .windowsupdate.microsoft.com
7229 mail.google.com</PRE
7235 > Shopping sites are not as fragile, but they typically
7236 require cookies to log in, and pop-up windows for shopping
7237 carts or item details. Again, we'll use a pre-defined alias:</P
7251 .worldpay.com # for quietpc.com
7262 HREF="actions-file.html#FAST-REDIRECTS"
7266 action, which may have been enabled in <TT
7268 >match-all.action</TT
7270 breaks some sites. So disable it for popular sites where we know it misbehaves:</P
7281 HREF="actions-file.html#FAST-REDIRECTS"
7287 .altavista.com/.*(like|url|link):http
7288 .altavista.com/trans.*urltext=http
7295 > It is important that <SPAN
7299 URLs belong to images, so that <SPAN
7306 be blocked, a substitute image can be sent, rather than an HTML page.
7307 Contacting the remote site to find out is not an option, since it
7308 would destroy the loading time advantage of banner blocking, and it
7309 would feed the advertisers information about you. We can mark any
7310 URL as an image with the <TT
7313 HREF="actions-file.html#HANDLE-AS-IMAGE"
7317 and marking all URLs that end in a known image file extension is a
7328 >##########################################################################
7330 ##########################################################################
7332 # Define which file types will be treated as images, in case they get
7333 # blocked further down this file:
7336 HREF="actions-file.html#HANDLE-AS-IMAGE"
7339 /.*\.(gif|jpe?g|png|bmp|ico)$</PRE
7345 > And then there are known banner sources. They often use scripts to
7346 generate the banners, so it won't be visible from the URL that the
7347 request is for an image. Hence we block them <SPAN
7354 mark them as images in one go, with the help of our
7357 >+block-as-image</TT
7358 > alias defined above. (We could of
7359 course just as well use <TT
7362 HREF="actions-file.html#BLOCK"
7366 HREF="actions-file.html#HANDLE-AS-IMAGE"
7370 Remember that the type of the replacement image is chosen by the
7374 HREF="actions-file.html#SET-IMAGE-BLOCKER"
7375 >set-image-blocker</A
7378 action. Since all URLs have matched the default section with its
7382 HREF="actions-file.html#SET-IMAGE-BLOCKER"
7383 >set-image-blocker</A
7386 action before, it still applies and needn't be repeated:</P
7396 ># Known ad generators:
7401 .ad.*.doubleclick.net
7402 .a.yimg.com/(?:(?!/i/).)*$
7403 .a[0-9].yimg.com/(?:(?!/i/).)*$
7411 > One of the most important jobs of <SPAN
7415 is to block banners. Many of these can be <SPAN
7422 HREF="actions-file.html#FILTER"
7424 >{banners-by-size}</TT
7426 action, which we enabled above, and which deletes the references to banner
7427 images from the pages while they are loaded, so the browser doesn't request
7428 them anymore, and hence they don't need to be blocked here. But this naturally
7429 doesn't catch all banners, and some people choose not to use filters, so we
7430 need a comprehensive list of patterns for banner URLs here, and apply the
7434 HREF="actions-file.html#BLOCK"
7437 > action to them.</P
7439 > First comes many generic patterns, which do most of the work, by
7440 matching typical domain and path name components of banners. Then comes
7441 a list of individual patterns for specific sites, which is omitted here
7442 to keep the example short:</P
7452 >##########################################################################
7453 # Block these fine banners:
7454 ##########################################################################
7456 HREF="actions-file.html#BLOCK"
7457 >+block{Banner ads.}</A
7466 /.*count(er)?\.(pl|cgi|exe|dll|asp|php[34]?)
7467 /(?:.*/)?(publicite|werbung|rekla(ma|me|am)|annonse|maino(kset|nta|s)?)/
7469 # Site-specific patterns (abbreviated):
7477 > It's quite remarkable how many advertisers actually call their banner
7483 >.com, or call the directory
7484 in which the banners are stored simply <SPAN
7488 generic patterns are surprisingly effective.</P
7490 > But being very generic, they necessarily also catch URLs that we don't want
7491 to block. The pattern <TT
7503 >.nasty-corp.com"</SPAN
7513 >.sourcefroge.net"</SPAN
7523 >l.some-provider.net."</SPAN
7525 well-known exceptions to the <TT
7528 HREF="actions-file.html#BLOCK"
7534 > Note that these are exceptions to exceptions from the default! Consider the URL
7537 >"downloads.sourcefroge.net"</SPAN
7538 >: Initially, all actions are deactivated,
7539 so it wouldn't get blocked. Then comes the defaults section, which matches the
7540 URL, but just deactivates the <TT
7543 HREF="actions-file.html#BLOCK"
7547 action once again. Then it matches <TT
7550 >, an exception to the
7551 general non-blocking policy, and suddenly
7555 HREF="actions-file.html#BLOCK"
7558 > applies. And now, it'll match
7565 HREF="actions-file.html#BLOCK"
7569 applies, so (unless it matches <SPAN
7575 > further down) it ends up
7579 HREF="actions-file.html#BLOCK"
7582 > action applying.</P
7592 >##########################################################################
7593 # Save some innocent victims of the above generic block patterns:
7594 ##########################################################################
7599 HREF="actions-file.html#BLOCK"
7602 adv[io]*. # (for advogato.org and advice.*)
7603 adsl. # (has nothing to do with ads)
7604 adobe. # (has nothing to do with ads either)
7605 ad[ud]*. # (adult.* and add.*)
7606 .edu # (universities don't host banners (yet!))
7607 .*loads. # (downloads, uploads etc)
7615 www.globalintersec.com/adv # (adv = advanced)
7616 www.ugu.com/sui/ugu/adv</PRE
7622 > Filtering source code can have nasty side effects,
7623 so make an exception for our friends at sourceforge.net,
7624 and all paths with <SPAN
7627 > in them. Note that
7631 HREF="actions-file.html#FILTER"
7641 > filters in one fell swoop!</P
7651 ># Don't filter code!
7654 HREF="actions-file.html#FILTER"
7661 .sourceforge.net</PRE
7670 > is of course much more
7671 comprehensive, but we hope this example made clear how it works.</P
7679 >8.7.3. user.action</A
7682 > So far we are painting with a broad brush by setting general policies,
7683 which would be a reasonable starting point for many people. Now,
7684 you might want to be more specific and have customized rules that
7685 are more suitable to your personal habits and preferences. These would
7686 be for narrowly defined situations like your ISP or your bank, and should
7690 >, which is parsed after all other
7691 actions files and hence has the last word, over-riding any previously
7692 defined actions. <TT
7702 > place for your personal settings, since
7706 > is actively maintained by the
7710 > developers and you'll probably want
7711 to install updated versions from time to time.</P
7713 > So let's look at a few examples of things that one might typically do in
7727 ># My user.action file. <fred@example.com></PRE
7734 HREF="actions-file.html#ALIASES"
7736 > are local to the actions
7737 file that they are defined in, you can't use the ones from
7741 >, unless you repeat them here:</P
7751 ># Aliases are local to the file they are defined in.
7752 # (Re-)define aliases for this file:
7756 # These aliases just save typing later, and the alias names should
7757 # be self explanatory.
7759 +crunch-all-cookies = +crunch-incoming-cookies +crunch-outgoing-cookies
7760 -crunch-all-cookies = -crunch-incoming-cookies -crunch-outgoing-cookies
7761 allow-all-cookies = -crunch-all-cookies -session-cookies-only
7762 allow-popups = -filter{all-popups}
7763 +block-as-image = +block{Blocked as image.} +handle-as-image
7764 -block-as-image = -block
7766 # These aliases define combinations of actions that are useful for
7767 # certain types of sites:
7769 fragile = -block -crunch-all-cookies -filter -fast-redirects -hide-referrer
7770 shop = -crunch-all-cookies allow-popups
7772 # Allow ads for selected useful free sites:
7774 allow-ads = -block -filter{banners-by-size} -filter{banners-by-link}
7776 # Alias for specific file types that are text, but might have conflicting
7777 # MIME types. We want the browser to force these to be text documents.
7778 handle-as-text = -<A
7779 HREF="actions-file.html#FILTER"
7782 HREF="actions-file.html#CONTENT-TYPE-OVERWRITE"
7783 >content-type-overwrite{text/plain}</A
7785 HREF="actions-file.html#FORCE-TEXT-MODE"
7788 HREF="actions-file.html#HIDE-CONTENT-DISPOSITION"
7789 >hide-content-disposition</A
7796 > Say you have accounts on some sites that you visit regularly, and
7797 you don't want to have to log in manually each time. So you'd like
7798 to allow persistent cookies for these sites. The
7801 >allow-all-cookies</TT
7802 > alias defined above does exactly
7803 that, i.e. it disables crunching of cookies in any direction, and the
7804 processing of cookies to make them only temporary.</P
7814 >{ allow-all-cookies }
7824 > Your bank is allergic to some filter, but you don't know which, so you disable them all:</P
7835 HREF="actions-file.html#FILTER"
7838 .your-home-banking-site.com</PRE
7844 > Some file types you may not want to filter for various reasons:</P
7854 ># Technical documentation is likely to contain strings that might
7855 # erroneously get altered by the JavaScript-oriented filters:
7860 # And this stupid host sends streaming video with a wrong MIME type,
7861 # so that Privoxy thinks it is getting HTML and starts filtering:
7863 stupid-server.example.com/</PRE
7869 > Example of a simple <A
7870 HREF="actions-file.html#BLOCK"
7872 > action. Say you've
7873 seen an ad on your favourite page on example.com that you want to get rid of.
7874 You have right-clicked the image, selected <SPAN
7876 >"copy image location"</SPAN
7878 and pasted the URL below while removing the leading http://, into a
7882 > section. Note that <TT
7886 > need not be specified, since all URLs ending in
7890 > will be tagged as images by the general rules as set
7891 in default.action anyway:</P
7902 HREF="actions-file.html#BLOCK"
7905 www.example.com/nasty-ads/sponsor\.gif
7906 another.example.net/more/junk/here/</PRE
7912 > The URLs of dynamically generated banners, especially from large banner
7913 farms, often don't use the well-known image file name extensions, which
7914 makes it impossible for <SPAN
7918 the file type just by looking at the URL.
7921 >+block-as-image</TT
7922 > alias defined above for
7924 Note that objects which match this rule but then turn out NOT to be an
7925 image are typically rendered as a <SPAN
7927 >"broken image"</SPAN
7929 browser. Use cautiously.</P
7939 >{ +block-as-image }
7949 > Now you noticed that the default configuration breaks Forbes Magazine,
7950 but you were too lazy to find out which action is the culprit, and you
7951 were again too lazy to give <A
7955 you just used the <TT
7958 > alias on the site, and
7965 > -- it worked. The <TT
7969 aliases disables those actions that are most likely to break a site. Also,
7970 good for testing purposes to see if it is <SPAN
7974 that is causing the problem or not. We later find other regular sites
7975 that misbehave, and add those to our personalized list of troublemakers:</P
7994 > You like the <SPAN
7997 > text replacements in <TT
8001 but it is disabled in the distributed actions file.
8002 So you'd like to turn it on in your private,
8003 update-safe config, once and for all:</P
8014 HREF="actions-file.html#FILTER-FUN"
8017 / # For ALL sites!</PRE
8023 > Note that the above is not really a good idea: There are exceptions
8024 to the filters in <TT
8028 really shouldn't be filtered, like code on CVS->Web interfaces. Since
8032 > has the last word, these exceptions
8033 won't be valid for the <SPAN
8036 > filtering specified here.</P
8038 > You might also worry about how your favourite free websites are
8039 funded, and find that they rely on displaying banner advertisements
8040 to survive. So you might want to specifically allow banners for those
8041 sites that you feel provide value to you:</P
8063 > has been aliased to
8067 HREF="actions-file.html#BLOCK"
8074 HREF="actions-file.html#FILTER-BANNERS-BY-SIZE"
8075 >filter{banners-by-size}</A
8081 HREF="actions-file.html#FILTER-BANNERS-BY-LINK"
8082 >filter{banners-by-link}</A
8086 > Invoke another alias here to force an over-ride of the MIME type <TT
8088 > application/x-sh</TT
8089 > which typically would open a download type
8090 dialog. In my case, I want to look at the shell script, and then I can save
8091 it should I choose to.</P
8111 > is generally the best place to define
8112 exceptions and additions to the default policies of
8116 >. Some actions are safe to have their
8117 default policies set here though. So let's set a default policy to have a
8121 > image as opposed to the checkerboard pattern for
8131 > of course matches all URL
8132 paths and patterns:</P
8143 HREF="actions-file.html#SET-IMAGE-BLOCKER"
8144 >set-image-blocker{blank}</A
8159 SUMMARY="Footer navigation table"
8188 HREF="filter-file.html"
8198 >The Main Configuration File</TD