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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
120 > - is the primary action file
121 that sets the initial values for all actions. It is intended to
122 provide a base level of functionality for
126 > array of features. So it is
127 a set of broad rules that should work reasonably well as-is for most users.
128 This is the file that the developers are keeping updated, and <A
129 HREF="installation.html#INSTALLATION-KEEPUPDATED"
130 >making available to users</A
132 It also contains the pre-defined sets of rules for the default actions,
152 > - is intended to be for local site
153 preferences and exceptions. As an example, if your ISP or your bank
154 has specific requirements, and need special handling, this kind of
155 thing should go here. This file will not be upgraded.
165 >Set to Cautious</SPAN
171 >Set to Advanced</SPAN
175 > These have increasing levels of aggressiveness <SPAN
180 influence on your browsing unless you select them explicitly in the
183 >. A default installation should be pre-set to
187 > (versions prior to 3.0.5 were set to
191 >). New users should try this for a while before
192 adjusting the settings to more aggressive levels. The more aggressive
193 the settings, then the more likelihood there is of problems such as sites
194 not working as they should.
200 > button allows you to turn each
201 action on/off individually for fine-tuning. The <SPAN
205 button changes the actions list to low/safe settings which will activate
206 ad blocking and a minimal set of <SPAN
209 >'s features, and subsequently
210 there will be less of a chance for accidental problems. The
214 > button sets the list to a medium level of
215 other features and a low level set of privacy features. The
219 > button sets the list to a high level of
220 ad blocking and medium level of privacy. See the chart below. The latter
221 three buttons over-ride any changes via with the
225 > button. More fine-tuning can be done in the
226 lower sections of this internal page.
229 > The default profiles, and their associated actions, as pre-defined in
243 >Table 1. Default Configurations</B
273 >Ad-blocking Aggressiveness</TD
283 >Ad-filtering by size</TD
293 >Ad-filtering by link</TD
313 >Privacy Features</TD
343 >GIF de-animation</TD
373 >JavaScript taming</TD
393 >Image tag reordering</TD
411 > The list of actions files to be used are defined in the main configuration
412 file, and are processed in the order they are defined (e.g.
416 > is typically processed before
420 >). The content of these can all be viewed and
422 HREF="http://config.privoxy.org/show-status"
424 >http://config.privoxy.org/show-status</A
426 The over-riding principle when applying actions, is that the last action that
427 matches a given URL wins. The broadest, most general rules go first
432 followed by any exceptions (typically also in
436 >), which are then followed lastly by any
437 local preferences (typically in <SPAN
453 > An actions file typically has multiple sections. If you want to use
457 > in an actions file, you have to place the (optional)
459 HREF="actions-file.html#ALIASES"
461 > at the top of that file.
462 Then comes the default set of rules which will apply universally to all
463 sites and pages (be <SPAN
473 > or any other actions file after
477 >, because it will override the result
478 from consulting any previous file). And then below that,
479 exceptions to the defined universal policies. You can regard
483 > as an appendix to <TT
487 with the advantage that it is a separate file, which makes preserving your
488 personal settings across <SPAN
491 > upgrades easier.</P
494 Actions can be used to block anything you want, including ads, banners, or
495 just some obnoxious URL whose content you would rather not see. Cookies can be accepted
496 or rejected, or accepted only during the current browser session (i.e. not
497 written to disk), content can be modified, some JavaScripts tamed, user-tracking
498 fooled, and much more. See below for a <A
499 HREF="actions-file.html#ACTIONS"
509 >8.1. Finding the Right Mix</A
513 HREF="actions-file.html#ACTIONS"
515 >, like cookie suppression
516 or script disabling, may render some sites unusable that rely on these
517 techniques to work properly. Finding the right mix of actions is not always easy and
518 certainly a matter of personal taste. And, things can always change, requiring
519 refinements in the configuration. In general, it can be said that the more
523 > your default settings (in the top section of the
524 actions file) are, the more exceptions for <SPAN
528 will have to make later. If, for example, you want to crunch all cookies per
529 default, you'll have to make exceptions from that rule for sites that you
530 regularly use and that require cookies for actually useful purposes, like maybe
531 your bank, favorite shop, or newspaper.</P
533 > We have tried to provide you with reasonable rules to start from in the
534 distribution actions files. But there is no general rule of thumb on these
535 things. There just are too many variables, and sites are constantly changing.
536 Sooner or later you will want to change the rules (and read this chapter again :).</P
547 > The easiest way to edit the actions files is with a browser by
548 using our browser-based editor, which can be reached from <A
549 HREF="http://config.privoxy.org/show-status"
551 >http://config.privoxy.org/show-status</A
553 Note: the config file option <A
554 HREF="config.html#ENABLE-EDIT-ACTIONS"
555 >enable-edit-actions</A
556 > must be enabled for
557 this to work. The editor allows both fine-grained control over every single
558 feature on a per-URL basis, and easy choosing from wholesale sets of defaults
569 >. Warning: the <SPAN
573 aggressive, and will be more likely to cause problems for some sites.
574 Experienced users only!
577 > If you prefer plain text editing to GUIs, you can of course also directly edit the
578 the actions files with your favorite text editor. Look at
582 > which is richly commented with many
591 >8.3. How Actions are Applied to Requests</A
594 > Actions files are divided into sections. There are special sections,
598 HREF="actions-file.html#ALIASES"
601 > sections which will
602 be discussed later. For now let's concentrate on regular sections: They have a
603 heading line (often split up to multiple lines for readability) which consist
604 of a list of actions, separated by whitespace and enclosed in curly braces.
605 Below that, there is a list of URL and tag patterns, each on a separate line.</P
607 > To determine which actions apply to a request, the URL of the request is
608 compared to all URL patterns in each <SPAN
612 Every time it matches, the list of applicable actions for the request is
613 incrementally updated, using the heading of the section in which the
614 pattern is located. The same is done again for tags and tag patterns later on.</P
616 > If multiple applying sections set the same action differently,
617 the last match wins. If not, the effects are aggregated.
618 E.g. a URL might match a regular section with a heading line of <TT
622 HREF="actions-file.html#HANDLE-AS-IMAGE"
626 then later another one with just <TT
630 HREF="actions-file.html#BLOCK"
640 > actions to apply. And there may well be
641 cases where you will want to combine actions together. Such a section then
657 >block{Banner ads.}</TT
659 # Block these as if they were images. Send no block page.
661 media.example.com/.*banners
662 .example.com/images/ads/</PRE
669 > You can trace this process for URL patterns and any given URL by visiting <A
670 HREF="http://config.privoxy.org/show-url-info"
672 >http://config.privoxy.org/show-url-info</A
675 > Examples and more detail on this is provided in the Appendix, <A
676 HREF="appendix.html#ACTIONSANAT"
677 > Troubleshooting: Anatomy of an Action</A
697 to determine what <SPAN
703 > might apply to which sites and
704 pages your browser attempts to access. These <SPAN
714 > matching to achieve a high degree of
715 flexibility. This allows one expression to be expanded and potentially match
716 against many similar patterns.</P
718 > Generally, an URL pattern has the form
721 ><domain>/<path></TT
725 ><domain></TT
730 optional. (This is why the special <TT
733 > pattern matches all
734 URLs). Note that the protocol portion of the URL pattern (e.g.
745 the pattern. This is assumed already!</P
747 > The pattern matching syntax is different for the domain and path parts of
748 the URL. The domain part uses a simple globbing type matching technique,
749 while the path part uses more flexible
751 HREF="http://en.wikipedia.org/wiki/Regular_expressions"
767 >www.example.com/</TT
771 > is a domain-only pattern and will match any request to <TT
775 regardless of which document on that server is requested. So ALL pages in
776 this domain would be covered by the scope of this action. Note that a
780 > is different and would NOT match.
790 > means exactly the same. For domain-only patterns, the trailing <TT
800 >www.example.com/index.html</TT
804 > matches all the documents on <TT
808 whose name starts with <TT
817 >www.example.com/index.html$</TT
821 > matches only the single document <TT
838 > matches the document <TT
841 >, regardless of the domain,
848 > web server anywhere.
858 > matches nothing, since it would be interpreted as a domain name and
859 there is no top-level domain called <TT
874 >8.4.1. The Domain Pattern</A
877 > The matching of the domain part offers some flexible options: if the
878 domain starts or ends with a dot, it becomes unanchored at that end.
892 > matches any domain with first-level domain <TT
896 and second-level domain <TT
909 >foo.bar.baz.example.com</TT
911 Note that it wouldn't match if the second-level domain was <TT
924 > matches any domain that <SPAN
934 > (It also matches the domain
938 > but most of the time that doesn't matter.)
948 > matches any domain that <SPAN
958 And, by the way, also included would be any files or documents that exist
959 within that domain since no path limitations are specified. (Correctly
960 speaking: It matches any FQDN that contains <TT
964 a domain.) This might be <TT
974 >www.example.net/cgi/testing.pl</TT
975 > for instance. All these
982 > Additionally, there are wild-cards that you can use in the domain names
983 themselves. These work similarly to shell globbing type wild-cards:
987 > represents zero or more arbitrary characters (this is
990 HREF="http://en.wikipedia.org/wiki/Regular_expressions"
997 > based syntax of <SPAN
1004 > represents any single character (this is equivalent to the
1005 regular expression syntax of a simple <SPAN
1008 >), and you can define
1011 >"character classes"</SPAN
1012 > in square brackets which is similar to
1013 the same regular expression technique. All of this can be freely mixed:</P
1017 CLASS="VARIABLELIST"
1022 >ad*.example.com</TT
1028 >"adserver.example.com"</SPAN
1032 >"ads.example.com"</SPAN
1033 >, etc but not <SPAN
1035 >"sfads.example.com"</SPAN
1042 >*ad*.example.com</TT
1046 > matches all of the above, and then some.
1062 >pictures.epix.com</TT
1065 >a.b.c.d.e.upix.com</TT
1072 >www[1-9a-ez].example.c*</TT
1078 >www1.example.com</TT
1082 >www4.example.cc</TT
1085 >wwwd.example.cy</TT
1089 >wwwz.example.com</TT
1099 >wwww.example.com</TT
1106 > While flexible, this is not the sophistication of full regular expression based syntax.</P
1114 >8.4.2. The Path Pattern</A
1125 HREF="http://en.wikipedia.org/wiki/Regular_expressions"
1132 > for matching the path portion (after the slash),
1133 and is thus more flexible.</P
1136 HREF="appendix.html#REGEX"
1138 > with a brief quick-start into regular
1139 expressions, you also might want to have a look at your operating system's documentation
1140 on regular expressions (try <TT
1145 > Note that the path pattern is automatically left-anchored at the <SPAN
1149 i.e. it matches as if it would start with a <SPAN
1152 > (regular expression speak
1153 for the beginning of a line).</P
1155 > Please also note that matching in the path is <SPAN
1159 >CASE INSENSITIVE</I
1162 by default, but you can switch to case sensitive at any point in the pattern by using the
1168 >www.example.com/(?-i)PaTtErN.*</TT
1170 only documents whose path starts with <TT
1180 > this capitalization.</P
1184 CLASS="VARIABLELIST"
1189 >.example.com/.*</TT
1193 > Is equivalent to just <SPAN
1195 >".example.com"</SPAN
1196 >, since any documents
1197 within that domain are matched with or without the <SPAN
1201 regular expression. This is redundant
1207 >.example.com/.*/index.html$</TT
1211 > Will match any page in the domain of <SPAN
1213 >"example.com"</SPAN
1218 >, and that is part of some path. For
1219 example, it matches <SPAN
1221 >"www.example.com/testing/index.html"</SPAN
1225 >"www.example.com/index.html"</SPAN
1226 > because the regular
1227 expression called for at least two <SPAN
1231 requirement. It also would match
1234 >"www.example.com/testing/index_html"</SPAN
1236 special meta-character <SPAN
1245 >.example.com/(.*/)?index\.html$</TT
1249 > This regular expression is conditional so it will match any page
1253 > regardless of path which in this case can
1254 have one or more <SPAN
1257 >. And this one must contain exactly
1261 > (but does not have to end with that!).
1267 >.example.com/(.*/)(ads|banners?|junk)</TT
1271 > This regular expression will match any path of <SPAN
1273 >"example.com"</SPAN
1275 that contains any of the words <SPAN
1285 > (because of the <SPAN
1292 The path does not have to end in these words, just contain them.
1298 >.example.com/(.*/)(ads|banners?|junk)/.*\.(jpe?g|gif|png)$</TT
1302 > This is very much the same as above, except now it must end in either
1316 one is limited to common image formats.
1322 > There are many, many good examples to be found in <TT
1326 and more tutorials below in <A
1327 HREF="appendix.html#REGEX"
1328 >Appendix on regular expressions</A
1337 >8.4.3. The Tag Pattern</A
1340 > Tag patterns are used to change the applying actions based on the
1341 request's tags. Tags can be created with either the
1343 HREF="actions-file.html#CLIENT-HEADER-TAGGER"
1344 >client-header-tagger</A
1347 HREF="actions-file.html#SERVER-HEADER-TAGGER"
1348 >server-header-tagger</A
1351 > Tag patterns have to start with <SPAN
1358 can tell them apart from URL patterns. Everything after the colon
1359 including white space, is interpreted as a regular expression with
1360 path pattern syntax, except that tag patterns aren't left-anchored
1361 automatically (<SPAN
1364 > doesn't silently add a <SPAN
1368 you have to do it yourself if you need it).</P
1370 > To match all requests that are tagged with <SPAN
1374 your pattern line should be <SPAN
1381 > would work as well, but it would also
1382 match requests whose tags contain <SPAN
1389 > wouldn't work as it requires white space.</P
1391 > Sections can contain URL and tag patterns at the same time,
1392 but tag patterns are checked after the URL patterns and thus
1393 always overrule them, even if they are located before the URL patterns.</P
1395 > Once a new tag is added, Privoxy checks right away if it's matched by one
1396 of the tag patterns and updates the action settings accordingly. As a result
1397 tags can be used to activate other tagger actions, as long as these other
1398 taggers look for headers that haven't already be parsed.</P
1400 > For example you could tag client requests which use the
1405 then use this tag to activate another tagger that adds a tag if cookies
1406 are sent, and then use a block action based on the cookie tag. This allows
1407 the outcome of one action, to be input into a subsequent action. However if
1408 you'd reverse the position of the described taggers, and activated the
1409 method tagger based on the cookie tagger, no method tags would be created.
1410 The method tagger would look for the request line, but at the time
1411 the cookie tag is created, the request line has already been parsed.</P
1413 > While this is a limitation you should be aware of, this kind of
1414 indirection is seldom needed anyway and even the example doesn't
1415 make too much sense.</P
1427 > All actions are disabled by default, until they are explicitly enabled
1428 somewhere in an actions file. Actions are turned on if preceded with a
1432 >, and turned off if preceded with a <SPAN
1441 >"do that action"</SPAN
1448 >"please block URLs that match the
1449 following patterns"</SPAN
1456 block URLs that match the following patterns, even if <TT
1460 previously applied."</SPAN
1464 Again, actions are invoked by placing them on a line, enclosed in curly braces and
1465 separated by whitespace, like in
1468 >{+some-action -some-other-action{some-parameter}}</TT
1470 followed by a list of URL patterns, one per line, to which they apply.
1471 Together, the actions line and the following pattern lines make up a section
1472 of the actions file. </P
1475 Actions fall into three categories:</P
1483 Boolean, i.e the action can only be <SPAN
1506 > # enable action <TT
1517 > # disable action <TT
1532 >+handle-as-image</TT
1539 Parameterized, where some value is required in order to enable this type of action.
1561 >} # enable action and set parameter to <TT
1567 # overwriting parameter from previous match if necessary
1573 > # disable action. The parameter can be omitted</PRE
1580 > Note that if the URL matches multiple positive forms of a parameterized action,
1581 the last match wins, i.e. the params from earlier matches are simply ignored.
1587 >+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
1594 Multi-value. These look exactly like parameterized actions,
1595 but they behave differently: If the action applies multiple times to the
1596 same URL, but with different parameters, <SPAN
1609 > matches are remembered. This is used for actions
1610 that can be executed for the same request repeatedly, like adding multiple
1611 headers, or filtering through multiple filters. Syntax:
1632 >} # enable action and add <TT
1637 > to the list of parameters
1648 >} # remove the parameter <TT
1653 > from the list of parameters
1654 # If it was the last one left, disable the action.
1660 > # disable this action completely and remove all parameters from the list</PRE
1670 >+add-header{X-Fun-Header: Some text}</TT
1674 >+filter{html-annoyances}</TT
1681 > If nothing is specified in any actions file, no <SPAN
1685 taken. So in this case <SPAN
1689 normal, non-blocking, non-filtering proxy. You must specifically enable the
1690 privacy and blocking features you need (although the provided default actions
1691 files will give a good starting point).</P
1693 > Later defined action sections always over-ride earlier ones of the same type.
1694 So exceptions to any rules you make, should come in the latter part of the file (or
1695 in a file that is processed later when using multiple actions files such
1699 >). For multi-valued actions, the actions
1700 are applied in the order they are specified. Actions files are processed in
1701 the order they are defined in <TT
1705 installation has three actions files). It also quite possible for any given
1706 URL to match more than one <SPAN
1709 > (because of wildcards and
1710 regular expressions), and thus to trigger more than one set of actions! Last
1713 > The list of valid <SPAN
1723 >8.5.1. add-header</A
1728 CLASS="VARIABLELIST"
1734 >Confuse log analysis, custom applications</P
1740 > Sends a user defined HTTP header to the web server.
1753 > Any string value is possible. Validity of the defined HTTP headers is not checked.
1754 It is recommended that you use the <SPAN
1768 > This action may be specified multiple times, in order to define multiple
1769 headers. This is rarely needed for the typical user. If you don't know what
1772 >"HTTP headers"</SPAN
1773 > are, you definitely don't need to worry about this
1789 >+add-header{X-User-Tracking: sucks}</PRE
1810 CLASS="VARIABLELIST"
1816 >Block ads or other unwanted content</P
1822 > Requests for URLs to which this action applies are blocked, i.e. the
1823 requests are trapped by <SPAN
1826 > and the requested URL is never retrieved,
1827 but is answered locally with a substitute page or image, as determined by
1831 HREF="actions-file.html#HANDLE-AS-IMAGE"
1838 HREF="actions-file.html#SET-IMAGE-BLOCKER"
1839 >set-image-blocker</A
1845 HREF="actions-file.html#HANDLE-AS-EMPTY-DOCUMENT"
1846 >handle-as-empty-document</A
1862 >A block reason that should be given to the user.</P
1871 > sends a special <SPAN
1875 for requests to blocked pages. This page contains the block reason given as
1876 parameter, a link to find out why the block action applies, and a click-through
1877 to the blocked content (the latter only if the force feature is available and
1882 A very important exception occurs if <SPAN
1895 HREF="actions-file.html#HANDLE-AS-IMAGE"
1899 apply to the same request: it will then be replaced by an image. If
1903 HREF="actions-file.html#SET-IMAGE-BLOCKER"
1904 >set-image-blocker</A
1907 (see below) also applies, the type of image will be determined by its parameter,
1908 if not, the standard checkerboard pattern is sent.
1911 > It is important to understand this process, in order
1912 to understand how <SPAN
1916 ads and other unwanted content. Blocking is a core feature, and one
1917 upon which various other features depend.
1923 HREF="actions-file.html#FILTER"
1927 action can perform a very similar task, by <SPAN
1931 banner images and other content through rewriting the relevant URLs in the
1932 document's HTML source, so they don't get requested in the first place.
1933 Note that this is a totally different technique, and it's easy to confuse the two.
1937 >Example usage (section):</DT
1948 >{+block{No nasty stuff for you.}}
1949 # Block and replace with "blocked" page
1950 .nasty-stuff.example.com
1952 {+block{Doubleclick banners.} +handle-as-image}
1953 # Block and replace with image
1957 {+block{Layered ads.} +handle-as-empty-document}
1958 # Block and then ignore
1959 adserver.example.net/.*\.js$</PRE
1974 NAME="CHANGE-X-FORWARDED-FOR"
1975 >8.5.3. change-x-forwarded-for</A
1980 CLASS="VARIABLELIST"
1986 >Improve privacy by not forwarding the source of the request in the HTTP headers.</P
1994 >"X-Forwarded-For:"</SPAN
1995 > HTTP header from the client request,
2016 > to delete the header.</P
2023 > to create the header (or append
2024 the client's IP address to an already existing one).
2033 > It is safe and recommended to use <TT
2039 > Forwarding the source address of the request may make
2040 sense in some multi-user setups but is also a privacy risk.
2055 >+change-x-forwarded-for{block}</PRE
2070 NAME="CLIENT-HEADER-FILTER"
2071 >8.5.4. client-header-filter</A
2076 CLASS="VARIABLELIST"
2082 > Rewrite or remove single client headers.
2089 > All client headers to which this action applies are filtered on-the-fly through
2090 the specified regular expression based substitutions.
2103 > The name of a client-header filter, as defined in one of the
2105 HREF="filter-file.html"
2114 > Client-header filters are applied to each header on its own, not to
2115 all at once. This makes it easier to diagnose problems, but on the downside
2116 you can't write filters that only change header x if header y's value is z.
2117 You can do that by using tags though.
2120 > Client-header filters are executed after the other header actions have finished
2121 and use their output as input.
2124 > If the request URL gets changed, <SPAN
2127 > will detect that and use the new
2128 one. This can be used to rewrite the request destination behind the client's
2129 back, for example to specify a Tor exit relay for certain requests.
2132 > Please refer to the <A
2133 HREF="filter-file.html"
2134 >filter file chapter</A
2136 to learn which client-header filters are available by default, and how to
2141 >Example usage (section):</DT
2152 ># Hide Tor exit notation in Host and Referer Headers
2153 {+client-header-filter{hide-tor-exit-notation}}
2170 NAME="CLIENT-HEADER-TAGGER"
2171 >8.5.5. client-header-tagger</A
2176 CLASS="VARIABLELIST"
2182 > Block requests based on their headers.
2189 > Client headers to which this action applies are filtered on-the-fly through
2190 the specified regular expression based substitutions, the result is used as
2204 > The name of a client-header tagger, as defined in one of the
2206 HREF="filter-file.html"
2215 > Client-header taggers are applied to each header on its own,
2216 and as the header isn't modified, each tagger <SPAN
2223 > Client-header taggers are the first actions that are executed
2224 and their tags can be used to control every other action.
2228 >Example usage (section):</DT
2239 ># Tag every request with the User-Agent header
2240 {+client-header-tagger{user-agent}}
2243 # Tagging itself doesn't change the action
2244 # settings, sections with TAG patterns do:
2246 # If it's a download agent, use a different forwarding proxy,
2247 # show the real User-Agent and make sure resume works.
2248 {+forward-override{forward-socks5 10.0.0.2:2222 .} \
2249 -hide-if-modified-since \
2250 -overwrite-last-modified \
2255 TAG:^User-Agent: NetBSD-ftp/
2256 TAG:^User-Agent: Novell ZYPP Installer
2257 TAG:^User-Agent: RPM APT-HTTP/
2258 TAG:^User-Agent: fetch libfetch/
2259 TAG:^User-Agent: Ubuntu APT-HTTP/
2260 TAG:^User-Agent: MPlayer/
2276 NAME="CONTENT-TYPE-OVERWRITE"
2277 >8.5.6. content-type-overwrite</A
2282 CLASS="VARIABLELIST"
2288 >Stop useless download menus from popping up, or change the browser's rendering mode</P
2294 > Replaces the <SPAN
2296 >"Content-Type:"</SPAN
2297 > HTTP server header.
2319 >"Content-Type:"</SPAN
2320 > HTTP server header is used by the
2321 browser to decide what to do with the document. The value of this
2322 header can cause the browser to open a download menu instead of
2323 displaying the document by itself, even if the document's format is
2324 supported by the browser.
2327 > The declared content type can also affect which rendering mode
2328 the browser chooses. If XHTML is delivered as <SPAN
2332 many browsers treat it as yet another broken HTML document.
2333 If it is send as <SPAN
2335 >"application/xml"</SPAN
2337 XHTML support will only display it, if the syntax is correct.
2340 > If you see a web site that proudly uses XHTML buttons, but sets
2343 >"Content-Type: text/html"</SPAN
2344 >, you can use <SPAN
2348 to overwrite it with <SPAN
2350 >"application/xml"</SPAN
2352 the web master's claim inside your XHTML-supporting browser.
2353 If the syntax is incorrect, the browser will complain loudly.
2356 > You can also go the opposite direction: if your browser prints
2357 error messages instead of rendering a document falsely declared
2358 as XHTML, you can overwrite the content type with
2362 > and have it rendered as broken HTML document.
2367 >content-type-overwrite</TT
2371 >"Content-Type:"</SPAN
2372 > headers that look like some kind of text.
2373 If you want to overwrite it unconditionally, you have to combine it with
2377 HREF="actions-file.html#FORCE-TEXT-MODE"
2381 This limitation exists for a reason, think twice before circumventing it.
2384 > Most of the time it's easier to replace this action with a custom
2388 HREF="actions-file.html#SERVER-HEADER-FILTER"
2389 >server-header filter</A
2392 It allows you to activate it for every document of a certain site and it will still
2393 only replace the content types you aimed at.
2396 > Of course you can apply <TT
2398 >content-type-overwrite</TT
2400 to a whole site and then make URL based exceptions, but it's a lot
2401 more work to get the same precision.
2405 >Example usage (sections):</DT
2416 ># Check if www.example.net/ really uses valid XHTML
2417 { +content-type-overwrite{application/xml} }
2420 # but leave the content type unmodified if the URL looks like a style sheet
2421 {-content-type-overwrite}
2422 www.example.net/.*\.css$
2423 www.example.net/.*style</PRE
2438 NAME="CRUNCH-CLIENT-HEADER"
2439 >8.5.7. crunch-client-header</A
2444 CLASS="VARIABLELIST"
2450 >Remove a client header <SPAN
2453 > has no dedicated action for.</P
2459 > Deletes every header sent by the client that contains the string the user supplied as parameter.
2479 > This action allows you to block client headers for which no dedicated
2487 > will remove every client header that
2488 contains the string you supplied as parameter.
2491 > Regular expressions are <SPAN
2498 use this action to block different headers in the same request, unless
2499 they contain the same string.
2504 >crunch-client-header</TT
2505 > is only meant for quick tests.
2506 If you have to block several different headers, or only want to modify
2507 parts of them, you should use a
2511 HREF="actions-file.html#CLIENT-HEADER-FILTER"
2512 >client-header filter</A
2535 > Don't block any header without understanding the consequences.
2543 >Example usage (section):</DT
2554 ># Block the non-existent "Privacy-Violation:" client header
2555 { +crunch-client-header{Privacy-Violation:} }
2572 NAME="CRUNCH-IF-NONE-MATCH"
2573 >8.5.8. crunch-if-none-match</A
2578 CLASS="VARIABLELIST"
2584 >Prevent yet another way to track the user's steps between sessions.</P
2592 >"If-None-Match:"</SPAN
2593 > HTTP client header.
2613 > Removing the <SPAN
2615 >"If-None-Match:"</SPAN
2616 > HTTP client header
2617 is useful for filter testing, where you want to force a real
2618 reload instead of getting status code <SPAN
2622 would cause the browser to use a cached copy of the page.
2625 > It is also useful to make sure the header isn't used as a cookie
2626 replacement (unlikely but possible).
2629 > Blocking the <SPAN
2631 >"If-None-Match:"</SPAN
2632 > header shouldn't cause any
2633 caching problems, as long as the <SPAN
2635 >"If-Modified-Since:"</SPAN
2637 isn't blocked or missing as well.
2640 > It is recommended to use this action together with
2644 HREF="actions-file.html#HIDE-IF-MODIFIED-SINCE"
2645 >hide-if-modified-since</A
2652 HREF="actions-file.html#OVERWRITE-LAST-MODIFIED"
2653 >overwrite-last-modified</A
2659 >Example usage (section):</DT
2670 ># Let the browser revalidate cached documents but don't
2671 # allow the server to use the revalidation headers for user tracking.
2672 {+hide-if-modified-since{-60} \
2673 +overwrite-last-modified{randomize} \
2674 +crunch-if-none-match}
2690 NAME="CRUNCH-INCOMING-COOKIES"
2691 >8.5.9. crunch-incoming-cookies</A
2696 CLASS="VARIABLELIST"
2702 > Prevent the web server from setting HTTP cookies on your system
2711 >"Set-Cookie:"</SPAN
2712 > HTTP headers from server replies.
2732 > This action is only concerned with <SPAN
2749 HREF="actions-file.html#CRUNCH-OUTGOING-COOKIES"
2750 >crunch-outgoing-cookies</A
2759 > to disable HTTP cookies completely.
2768 > to use this action in conjunction
2772 HREF="actions-file.html#SESSION-COOKIES-ONLY"
2773 >session-cookies-only</A
2776 since it would prevent the session cookies from being set. See also
2780 HREF="actions-file.html#FILTER-CONTENT-COOKIES"
2781 >filter-content-cookies</A
2798 >+crunch-incoming-cookies</PRE
2813 NAME="CRUNCH-SERVER-HEADER"
2814 >8.5.10. crunch-server-header</A
2819 CLASS="VARIABLELIST"
2825 >Remove a server header <SPAN
2828 > has no dedicated action for.</P
2834 > Deletes every header sent by the server that contains the string the user supplied as parameter.
2854 > This action allows you to block server headers for which no dedicated
2858 > action exists. <SPAN
2862 will remove every server header that contains the string you supplied as parameter.
2865 > Regular expressions are <SPAN
2872 use this action to block different headers in the same request, unless
2873 they contain the same string.
2878 >crunch-server-header</TT
2879 > is only meant for quick tests.
2880 If you have to block several different headers, or only want to modify
2881 parts of them, you should use a custom
2885 HREF="actions-file.html#SERVER-HEADER-FILTER"
2886 >server-header filter</A
2909 > Don't block any header without understanding the consequences.
2917 >Example usage (section):</DT
2928 ># Crunch server headers that try to prevent caching
2929 { +crunch-server-header{no-cache} }
2945 NAME="CRUNCH-OUTGOING-COOKIES"
2946 >8.5.11. crunch-outgoing-cookies</A
2951 CLASS="VARIABLELIST"
2957 > Prevent the web server from reading any HTTP cookies from your system
2967 > HTTP headers from client requests.
2987 > This action is only concerned with <SPAN
3004 HREF="actions-file.html#CRUNCH-INCOMING-COOKIES"
3005 >crunch-incoming-cookies</A
3014 > to disable HTTP cookies completely.
3023 > to use this action in conjunction
3027 HREF="actions-file.html#SESSION-COOKIES-ONLY"
3028 >session-cookies-only</A
3031 since it would prevent the session cookies from being read.
3046 >+crunch-outgoing-cookies</PRE
3061 NAME="DEANIMATE-GIFS"
3062 >8.5.12. deanimate-gifs</A
3067 CLASS="VARIABLELIST"
3073 >Stop those annoying, distracting animated GIF images.</P
3079 > De-animate GIF animations, i.e. reduce them to their first or last image.
3105 > This will also shrink the images considerably (in bytes, not pixels!). If
3109 > is given, the first frame of the animation
3110 is used as the replacement. If <SPAN
3113 > is given, the last
3114 frame of the animation is used instead, which probably makes more sense for
3115 most banner animations, but also has the risk of not showing the entire
3116 last frame (if it is only a delta to an earlier frame).
3119 > You can safely use this action with patterns that will also match non-GIF
3120 objects, because no attempt will be made at anything that doesn't look like
3136 >+deanimate-gifs{last}</PRE
3151 NAME="DOWNGRADE-HTTP-VERSION"
3152 >8.5.13. downgrade-http-version</A
3157 CLASS="VARIABLELIST"
3163 >Work around (very rare) problems with HTTP/1.1</P
3169 > Downgrades HTTP/1.1 client requests and server replies to HTTP/1.0.
3189 > This is a left-over from the time when <SPAN
3193 didn't support important HTTP/1.1 features well. It is left here for the
3194 unlikely case that you experience HTTP/1.1 related problems with some server
3195 out there. Not all HTTP/1.1 features and requirements are supported yet,
3196 so there is a chance you might need this action.
3200 >Example usage (section):</DT
3211 >{+downgrade-http-version}
3212 problem-host.example.com</PRE
3227 NAME="FAST-REDIRECTS"
3228 >8.5.14. fast-redirects</A
3233 CLASS="VARIABLELIST"
3239 >Fool some click-tracking scripts and speed up indirect links.</P
3245 > Detects redirection URLs and redirects the browser without contacting
3246 the redirection server first.
3265 >"simple-check"</SPAN
3266 > to just search for the string <SPAN
3270 to detect redirection URLs.
3277 >"check-decoded-url"</SPAN
3278 > to decode URLs (if necessary) before searching
3279 for redirection URLs.
3289 Many sites, like yahoo.com, don't just link to other sites. Instead, they
3290 will link to some script on their own servers, giving the destination as a
3291 parameter, which will then redirect you to the final target. URLs
3292 resulting from this scheme typically look like:
3295 >"http://www.example.org/click-tracker.cgi?target=http%3a//www.example.net/"</SPAN
3299 > Sometimes, there are even multiple consecutive redirects encoded in the
3300 URL. These redirections via scripts make your web browsing more traceable,
3301 since the server from which you follow such a link can see where you go
3302 to. Apart from that, valuable bandwidth and time is wasted, while your
3303 browser asks the server for one redirect after the other. Plus, it feeds
3307 > This feature is currently not very smart and is scheduled for improvement.
3308 If it is enabled by default, you will have to create some exceptions to
3309 this action. It can lead to failures in several ways:
3312 > Not every URLs with other URLs as parameters is evil.
3313 Some sites offer a real service that requires this information to work.
3314 For example a validation service needs to know, which document to validate.
3318 > assumes that every URL parameter that
3319 looks like another URL is a redirection target, and will always redirect to
3320 the last one. Most of the time the assumption is correct, but if it isn't,
3321 the user gets redirected anyway.
3324 > Another failure occurs if the URL contains other parameters after the URL parameter.
3328 >"http://www.example.org/?redirect=http%3a//www.example.net/&foo=bar"</SPAN
3330 contains the redirection URL <SPAN
3332 >"http://www.example.net/"</SPAN
3334 followed by another parameter. <TT
3338 and will cause a redirect to <SPAN
3340 >"http://www.example.net/&foo=bar"</SPAN
3342 Depending on the target server configuration, the parameter will be silently ignored
3345 >"page not found"</SPAN
3346 > error. You can prevent this problem by
3350 HREF="actions-file.html#REDIRECT"
3354 to remove the last part of the URL, but it requires a little effort.
3357 > To detect a redirection URL, <TT
3361 looks for the string <SPAN
3364 >, either in plain text
3365 (invalid but often used) or encoded as <SPAN
3369 Some sites use their own URL encoding scheme, encrypt the address
3370 of the target server or replace it with a database id. In theses cases
3374 > is fooled and the request reaches the
3375 redirection server where it probably gets logged.
3390 > { +fast-redirects{simple-check} }
3393 { +fast-redirects{check-decoded-url} }
3394 another.example.com/testing</PRE
3415 CLASS="VARIABLELIST"
3421 >Get rid of HTML and JavaScript annoyances, banner advertisements (by size),
3422 do fun text replacements, add personalized effects, etc.</P
3428 > All instances of text-based type, most notably HTML and JavaScript, to which
3429 this action applies, can be filtered on-the-fly through the specified regular
3430 expression based substitutions. (Note: as of version 3.0.3 plain text documents
3431 are exempted from filtering, because web servers often use the
3435 > MIME type for all files whose type they don't know.)
3448 > The name of a content filter, as defined in the <A
3449 HREF="filter-file.html"
3452 Filters can be defined in one or more files as defined by the
3456 HREF="config.html#FILTERFILE"
3467 > is the collection of filters
3468 supplied by the developers. Locally defined filters should go
3469 in their own file, such as <TT
3475 > When used in its negative form,
3476 and without parameters, <SPAN
3482 > filtering is completely disabled.
3489 > For your convenience, there are a number of pre-defined filters available
3490 in the distribution filter file that you can use. See the examples below for
3494 > Filtering requires buffering the page content, which may appear to
3495 slow down page rendering since nothing is displayed until all content has
3496 passed the filters. (It does not really take longer, but seems that way
3497 since the page is not incrementally displayed.) This effect will be more
3498 noticeable on slower connections.
3503 >"Rolling your own"</SPAN
3505 filters requires a knowledge of
3507 HREF="http://en.wikipedia.org/wiki/Regular_expressions"
3516 HREF="http://en.wikipedia.org/wiki/Html"
3523 This is very powerful feature, and potentially very intrusive.
3524 Filters should be used with caution, and where an equivalent
3531 > The amount of data that can be filtered is limited to the
3535 HREF="config.html#BUFFER-LIMIT"
3539 option in the main <A
3543 default is 4096 KB (4 Megs). Once this limit is exceeded, the buffered
3544 data, and all pending data, is passed through unfiltered.
3547 > Inappropriate MIME types, such as zipped files, are not filtered at all.
3548 (Again, only text-based types except plain text). Encrypted SSL data
3549 (from HTTPS servers) cannot be filtered either, since this would violate
3550 the integrity of the secure transaction. In some situations it might
3551 be necessary to protect certain text, like source code, from filtering
3552 by defining appropriate <TT
3558 > Compressed content can't be filtered either, unless <SPAN
3562 is compiled with zlib support (requires at least <SPAN
3569 > will decompress the content before filtering
3573 > If you use a <SPAN
3576 > version without zlib support, but want filtering to work on
3577 as much documents as possible, even those that would normally be sent compressed,
3578 you must use the <TT
3581 HREF="actions-file.html#PREVENT-COMPRESSION"
3582 >prevent-compression</A
3585 action in conjunction with <TT
3591 > Content filtering can achieve some of the same effects as the
3595 HREF="actions-file.html#BLOCK"
3599 action, i.e. it can be used to block ads and banners. But the mechanism
3600 works quite differently. One effective use, is to block ad banners
3601 based on their size (see below), since many of these seem to be somewhat
3608 > with suggestions for new or
3609 improved filters is particularly welcome!
3612 > The below list has only the names and a one-line description of each
3613 predefined filter. There are <A
3614 HREF="filter-file.html#PREDEFINED-FILTERS"
3616 verbose explanations</A
3617 > of what these filters do in the <A
3618 HREF="filter-file.html"
3619 >filter file chapter</A
3624 >Example usage (with filters from the distribution <TT
3629 HREF="filter-file.html#PREDEFINED-FILTERS"
3630 >the Predefined Filters section</A
3632 more explanation on each:</DT
3636 NAME="FILTER-JS-ANNOYANCES"
3647 >+filter{js-annoyances} # Get rid of particularly annoying JavaScript abuse.</PRE
3655 NAME="FILTER-JS-EVENTS"
3666 >+filter{js-events} # Kill all JS event bindings and timers (Radically destructive! Only for extra nasty sites).</PRE
3674 NAME="FILTER-HTML-ANNOYANCES"
3685 >+filter{html-annoyances} # Get rid of particularly annoying HTML abuse.</PRE
3693 NAME="FILTER-CONTENT-COOKIES"
3704 >+filter{content-cookies} # Kill cookies that come in the HTML or JS content.</PRE
3712 NAME="FILTER-REFRESH-TAGS"
3723 >+filter{refresh-tags} # Kill automatic refresh tags (for dial-on-demand setups).</PRE
3731 NAME="FILTER-UNSOLICITED-POPUPS"
3742 >+filter{unsolicited-popups} # Disable only unsolicited pop-up windows. Useful if your browser lacks this ability.</PRE
3750 NAME="FILTER-ALL-POPUPS"
3761 >+filter{all-popups} # Kill all popups in JavaScript and HTML. Useful if your browser lacks this ability.</PRE
3769 NAME="FILTER-IMG-REORDER"
3780 >+filter{img-reorder} # Reorder attributes in <img> tags to make the banners-by-* filters more effective.</PRE
3788 NAME="FILTER-BANNERS-BY-SIZE"
3799 >+filter{banners-by-size} # Kill banners by size.</PRE
3807 NAME="FILTER-BANNERS-BY-LINK"
3818 >+filter{banners-by-link} # Kill banners by their links to known clicktrackers.</PRE
3826 NAME="FILTER-WEBBUGS"
3837 >+filter{webbugs} # Squish WebBugs (1x1 invisible GIFs used for user tracking).</PRE
3845 NAME="FILTER-TINY-TEXTFORMS"
3856 >+filter{tiny-textforms} # Extend those tiny textareas up to 40x80 and kill the hard wrap.</PRE
3864 NAME="FILTER-JUMPING-WINDOWS"
3875 >+filter{jumping-windows} # Prevent windows from resizing and moving themselves.</PRE
3883 NAME="FILTER-FRAMESET-BORDERS"
3894 >+filter{frameset-borders} # Give frames a border and make them resizable.</PRE
3902 NAME="FILTER-DEMORONIZER"
3913 >+filter{demoronizer} # Fix MS's non-standard use of standard charsets.</PRE
3921 NAME="FILTER-SHOCKWAVE-FLASH"
3932 >+filter{shockwave-flash} # Kill embedded Shockwave Flash objects.</PRE
3940 NAME="FILTER-QUICKTIME-KIOSKMODE"
3951 >+filter{quicktime-kioskmode} # Make Quicktime movies saveable.</PRE
3970 >+filter{fun} # Text replacements for subversive browsing fun!</PRE
3978 NAME="FILTER-CRUDE-PARENTAL"
3989 >+filter{crude-parental} # Crude parental filtering. Note that this filter doesn't work reliably.</PRE
3997 NAME="FILTER-IE-EXPLOITS"
4008 >+filter{ie-exploits} # Disable some known Internet Explorer bug exploits.</PRE
4016 NAME="FILTER-SITE-SPECIFICS"
4027 >+filter{site-specifics} # Cure for site-specific problems. Don't apply generally!</PRE
4035 NAME="FILTER-NO-PING"
4046 >+filter{no-ping} # Removes non-standard ping attributes in <a> and <area> tags.</PRE
4054 NAME="FILTER-GOOGLE"
4065 >+filter{google} # CSS-based block for Google text ads. Also removes a width limitation and the toolbar advertisement.</PRE
4084 >+filter{yahoo} # CSS-based block for Yahoo text ads. Also removes a width limitation.</PRE
4103 >+filter{msn} # CSS-based block for MSN text ads. Also removes tracking URLs and a width limitation.</PRE
4111 NAME="FILTER-BLOGSPOT"
4122 >+filter{blogspot} # Cleans up some Blogspot blogs. Read the fine print before using this.</PRE
4137 NAME="FORCE-TEXT-MODE"
4138 >8.5.16. force-text-mode</A
4143 CLASS="VARIABLELIST"
4152 > to treat a document as if it was in some kind of <SPAN
4164 > Declares a document as text, even if the <SPAN
4166 >"Content-Type:"</SPAN
4167 > isn't detected as such.
4190 HREF="actions-file.html#FILTER"
4197 > tries to only filter files that are
4198 in some kind of text format. The same restrictions apply to
4202 HREF="actions-file.html#CONTENT-TYPE-OVERWRITE"
4203 >content-type-overwrite</A
4208 >force-text-mode</TT
4209 > declares a document as text,
4210 without looking at the <SPAN
4212 >"Content-Type:"</SPAN
4234 > Think twice before activating this action. Filtering binary data
4235 with regular expressions can cause file damage.
4270 NAME="FORWARD-OVERRIDE"
4271 >8.5.17. forward-override</A
4276 CLASS="VARIABLELIST"
4282 >Change the forwarding settings based on User-Agent or request origin</P
4288 > Overrules the forward directives in the configuration file.
4308 > to use a direct connection without any additional proxies.</P
4314 >"forward 127.0.0.1:8123"</SPAN
4315 > to use the HTTP proxy listening at 127.0.0.1 port 8123.
4322 >"forward-socks4a 127.0.0.1:9050 ."</SPAN
4323 > to use the socks4a proxy listening at
4324 127.0.0.1 port 9050. Replace <SPAN
4326 >"forward-socks4a"</SPAN
4329 >"forward-socks4"</SPAN
4331 to use a socks4 connection (with local DNS resolution) instead, use <SPAN
4333 >"forward-socks5"</SPAN
4335 for socks5 connections (with remote DNS resolution).
4342 >"forward-socks4a 127.0.0.1:9050 proxy.example.org:8000"</SPAN
4343 > to use the socks4a proxy
4344 listening at 127.0.0.1 port 9050 to reach the HTTP proxy listening at proxy.example.org port 8000.
4347 >"forward-socks4a"</SPAN
4350 >"forward-socks4"</SPAN
4351 > to use a socks4 connection
4352 (with local DNS resolution) instead, use <SPAN
4354 >"forward-socks5"</SPAN
4356 for socks5 connections (with remote DNS resolution).
4365 > This action takes parameters similar to the
4367 HREF="config.html#FORWARDING"
4369 > directives in the configuration
4370 file, but without the URL pattern. It can be used as replacement, but normally it's only
4371 used in cases where matching based on the request URL isn't sufficient.
4392 > Please read the description for the <A
4393 HREF="config.html#FORWARDING"
4396 using this action. Forwarding to the wrong people will reduce your privacy and increase the
4397 chances of man-in-the-middle attacks.
4400 > If the ports are missing or invalid, default values will be used. This might change
4401 in the future and you shouldn't rely on it. Otherwise incorrect syntax causes Privoxy
4406 HREF="http://config.privoxy.org/show-url-info"
4408 >show-url-info CGI page</A
4410 to verify that your forward settings do what you thought the do.
4429 ># Always use direct connections for requests previously tagged as
4432 >"User-Agent: fetch libfetch/2.0"</SPAN
4434 # resuming downloads continues to work.
4435 # This way you can continue to use Tor for your normal browsing,
4436 # without overloading the Tor network with your FreeBSD ports updates
4437 # or downloads of bigger files like ISOs.
4438 # Note that HTTP headers are easy to fake and therefore their
4439 # values are as (un)trustworthy as your clients and users.
4440 {+forward-override{forward .} \
4441 -hide-if-modified-since \
4442 -overwrite-last-modified \
4444 TAG:^User-Agent: fetch libfetch/2\.0$
4460 NAME="HANDLE-AS-EMPTY-DOCUMENT"
4461 >8.5.18. handle-as-empty-document</A
4466 CLASS="VARIABLELIST"
4472 >Mark URLs that should be replaced by empty documents <SPAN
4476 >if they get blocked</I
4484 > This action alone doesn't do anything noticeable. It just marks URLs.
4488 HREF="actions-file.html#BLOCK"
4498 the presence or absence of this mark decides whether an HTML <SPAN
4502 page, or an empty document will be sent to the client as a substitute for the blocked content.
4509 > document isn't literally empty, but actually contains a single space.
4529 > Some browsers complain about syntax errors if JavaScript documents
4530 are blocked with <SPAN
4534 default HTML page; this option can be used to silence them.
4535 And of course this action can also be used to eliminate the <SPAN
4539 BLOCKED message in frames.
4542 > The content type for the empty document can be specified with
4546 HREF="actions-file.html#CONTENT-TYPE-OVERWRITE"
4547 >content-type-overwrite{}</A
4550 but usually this isn't necessary.
4565 ># Block all documents on example.org that end with ".js",
4566 # but send an empty document instead of the usual HTML message.
4567 {+block{Blocked JavaScript} +handle-as-empty-document}
4584 NAME="HANDLE-AS-IMAGE"
4585 >8.5.19. handle-as-image</A
4590 CLASS="VARIABLELIST"
4596 >Mark URLs as belonging to images (so they'll be replaced by images <SPAN
4600 >if they do get blocked</I
4602 >, rather than HTML pages)</P
4608 > This action alone doesn't do anything noticeable. It just marks URLs as images.
4612 HREF="actions-file.html#BLOCK"
4622 the presence or absence of this mark decides whether an HTML <SPAN
4626 page, or a replacement image (as determined by the <TT
4629 HREF="actions-file.html#SET-IMAGE-BLOCKER"
4630 >set-image-blocker</A
4632 > action) will be sent to the
4633 client as a substitute for the blocked content.
4653 > The below generic example section is actually part of <TT
4657 It marks all URLs with well-known image file name extensions as images and should
4661 > Users will probably only want to use the handle-as-image action in conjunction with
4665 HREF="actions-file.html#BLOCK"
4668 >, to block sources of banners, whose URLs don't
4669 reflect the file type, like in the second example section.
4672 > Note that you cannot treat HTML pages as images in most cases. For instance, (in-line) ad
4673 frames require an HTML page to be sent, or they won't display properly.
4676 >handle-as-image</TT
4677 > in this situation will not replace the
4678 ad frame with an image, but lead to error messages.
4682 >Example usage (sections):</DT
4693 ># Generic image extensions:
4696 /.*\.(gif|jpg|jpeg|png|bmp|ico)$
4698 # These don't look like images, but they're banners and should be
4699 # blocked as images:
4701 {+block{Nasty banners.} +handle-as-image}
4702 nasty-banner-server.example.com/junk.cgi\?output=trash</PRE
4717 NAME="HIDE-ACCEPT-LANGUAGE"
4718 >8.5.20. hide-accept-language</A
4723 CLASS="VARIABLELIST"
4729 >Pretend to use different language settings.</P
4735 > Deletes or replaces the <SPAN
4737 >"Accept-Language:"</SPAN
4738 > HTTP header in client requests.
4754 >, or any user defined value.
4761 > Faking the browser's language settings can be useful to make a
4762 foreign User-Agent set with
4766 HREF="actions-file.html#HIDE-USER-AGENT"
4773 > However some sites with content in different languages check the
4776 >"Accept-Language:"</SPAN
4777 > to decide which one to take by default.
4778 Sometimes it isn't possible to later switch to another language without
4781 >"Accept-Language:"</SPAN
4785 > Therefore it's a good idea to either only change the
4788 >"Accept-Language:"</SPAN
4789 > header to languages you understand,
4790 or to languages that aren't wide spread.
4793 > Before setting the <SPAN
4795 >"Accept-Language:"</SPAN
4797 to a rare language, you should consider that it helps to
4798 make your requests unique and thus easier to trace.
4799 If you don't plan to change this header frequently,
4800 you should stick to a common language.
4804 >Example usage (section):</DT
4815 ># Pretend to use Canadian language settings.
4816 {+hide-accept-language{en-ca} \
4817 +hide-user-agent{Mozilla/5.0 (X11; U; OpenBSD i386; en-CA; rv:1.8.0.4) Gecko/20060628 Firefox/1.5.0.4} \
4834 NAME="HIDE-CONTENT-DISPOSITION"
4835 >8.5.21. hide-content-disposition</A
4840 CLASS="VARIABLELIST"
4846 >Prevent download menus for content you prefer to view inside the browser.</P
4852 > Deletes or replaces the <SPAN
4854 >"Content-Disposition:"</SPAN
4855 > HTTP header set by some servers.
4871 >, or any user defined value.
4878 > Some servers set the <SPAN
4880 >"Content-Disposition:"</SPAN
4882 documents they assume you want to save locally before viewing them.
4885 >"Content-Disposition:"</SPAN
4886 > header contains the file name
4887 the browser is supposed to use by default.
4890 > In most browsers that understand this header, it makes it impossible to
4897 > the document, without downloading it first,
4898 even if it's just a simple text file or an image.
4901 > Removing the <SPAN
4903 >"Content-Disposition:"</SPAN
4905 to prevent this annoyance, but some browsers additionally check the
4908 >"Content-Type:"</SPAN
4909 > header, before they decide if they can
4910 display a document without saving it first. In these cases, you have
4911 to change this header as well, before the browser stops displaying
4915 > It is also possible to change the server's file name suggestion
4916 to another one, but in most cases it isn't worth the time to set
4920 > This action will probably be removed in the future,
4921 use server-header filters instead.
4936 ># Disarm the download link in Sourceforge's patch tracker
4938 +content-type-overwrite{text/plain}\
4939 +hide-content-disposition{block} }
4940 .sourceforge.net/tracker/download\.php</PRE
4955 NAME="HIDE-IF-MODIFIED-SINCE"
4956 >8.5.22. hide-if-modified-since</A
4961 CLASS="VARIABLELIST"
4967 >Prevent yet another way to track the user's steps between sessions.</P
4975 >"If-Modified-Since:"</SPAN
4976 > HTTP client header or modifies its value.
4992 >, or a user defined value that specifies a range of hours.
4999 > Removing this header is useful for filter testing, where you want to force a real
5000 reload instead of getting status code <SPAN
5003 >, which would cause the
5004 browser to use a cached copy of the page.
5007 > Instead of removing the header, <TT
5009 >hide-if-modified-since</TT
5011 also add or subtract a random amount of time to/from the header's value.
5012 You specify a range of minutes where the random factor should be chosen from and
5016 > does the rest. A negative value means
5017 subtracting, a positive value adding.
5020 > Randomizing the value of the <SPAN
5022 >"If-Modified-Since:"</SPAN
5024 it less likely that the server can use the time as a cookie replacement,
5025 but you will run into caching problems if the random range is too high.
5028 > It is a good idea to only use a small negative value and let
5032 HREF="actions-file.html#OVERWRITE-LAST-MODIFIED"
5033 >overwrite-last-modified</A
5036 handle the greater changes.
5039 > It is also recommended to use this action together with
5043 HREF="actions-file.html#CRUNCH-IF-NONE-MATCH"
5044 >crunch-if-none-match</A
5047 otherwise it's more or less pointless.
5051 >Example usage (section):</DT
5062 ># Let the browser revalidate but make tracking based on the time less likely.
5063 {+hide-if-modified-since{-60} \
5064 +overwrite-last-modified{randomize} \
5065 +crunch-if-none-match}
5081 NAME="HIDE-FROM-HEADER"
5082 >8.5.23. hide-from-header</A
5087 CLASS="VARIABLELIST"
5093 >Keep your (old and ill) browser from telling web servers your email address</P
5099 > Deletes any existing <SPAN
5102 > HTTP header, or replaces it with the
5119 >, or any user defined value.
5129 > will completely remove the header
5130 (not to be confused with the <TT
5133 HREF="actions-file.html#BLOCK"
5140 > Alternately, you can specify any value you prefer to be sent to the web
5141 server. If you do, it is a matter of fairness not to use any address that
5142 is actually used by a real person.
5145 > This action is rarely needed, as modern web browsers don't send
5164 >+hide-from-header{block}</PRE
5177 >+hide-from-header{spam-me-senseless@sittingduck.example.com}</PRE
5192 NAME="HIDE-REFERRER"
5193 >8.5.24. hide-referrer</A
5201 CLASS="VARIABLELIST"
5207 >Conceal which link you followed to get to a particular site</P
5216 > (sic) HTTP header from the client request,
5217 or replaces it with a forged one.
5236 >"conditional-block"</SPAN
5237 > to delete the header completely if the host has changed.</P
5243 >"conditional-forge"</SPAN
5244 > to forge the header if the host has changed.</P
5251 > to delete the header unconditionally.</P
5258 > to pretend to be coming from the homepage of the server we are talking to.</P
5262 >Any other string to set a user defined referrer.</P
5272 >conditional-block</TT
5273 > is the only parameter,
5274 that isn't easily detected in the server's log file. If it blocks the
5275 referrer, the request will look like the visitor used a bookmark or
5276 typed in the address directly.
5279 > Leaving the referrer unmodified for requests on the same host
5280 allows the server owner to see the visitor's <SPAN
5284 but in most cases she could also get that information by comparing
5285 other parts of the log file: for example the User-Agent if it isn't
5286 a very common one, or the user's IP address if it doesn't change between
5290 > Always blocking the referrer, or using a custom one, can lead to
5291 failures on servers that check the referrer before they answer any
5292 requests, in an attempt to prevent their content from being
5293 embedded or linked to elsewhere.
5298 >conditional-block</TT
5303 will work with referrer checks, as long as content and valid referring page
5304 are on the same host. Most of the time that's the case.
5311 > is an alternate spelling of
5315 > and the two can be can be freely
5316 substituted with each other. (<SPAN
5320 correct English spelling, however the HTTP specification has a bug - it
5321 requires it to be spelled as <SPAN
5339 >+hide-referrer{forge}</PRE
5352 >+hide-referrer{http://www.yahoo.com/}</PRE
5367 NAME="HIDE-USER-AGENT"
5368 >8.5.25. hide-user-agent</A
5373 CLASS="VARIABLELIST"
5379 >Try to conceal your type of browser and client operating system</P
5385 > Replaces the value of the <SPAN
5387 >"User-Agent:"</SPAN
5389 in client requests with the specified value.
5402 > Any user-defined string.
5427 > This can lead to problems on web sites that depend on looking at this header in
5428 order to customize their content for different browsers (which, by the
5435 > the right thing to do: good web sites
5436 work browser-independently).
5443 > Using this action in multi-user setups or wherever different types of
5444 browsers will access the same <SPAN
5454 >. In single-user, single-browser
5455 setups, you might use it to delete your OS version information from
5456 the headers, because it is an invitation to exploit known bugs for your
5457 OS. It is also occasionally useful to forge this in order to access
5458 sites that won't let you in otherwise (though there may be a good
5459 reason in some cases). Example of this: some MSN sites will not
5463 > enter, yet forging to a
5467 > user-agent works just fine.
5468 (Must be just a silly MS goof, I'm sure :-).
5471 > More information on known user-agent strings can be found at
5473 HREF="http://www.user-agents.org/"
5475 >http://www.user-agents.org/</A
5479 HREF="http://en.wikipedia.org/wiki/User_agent"
5481 >http://en.wikipedia.org/wiki/User_agent</A
5497 >+hide-user-agent{Netscape 6.1 (X11; I; Linux 2.4.18 i686)}</PRE
5512 NAME="LIMIT-CONNECT"
5513 >8.5.26. limit-connect</A
5518 CLASS="VARIABLELIST"
5524 >Prevent abuse of <SPAN
5527 > as a TCP proxy relay or disable SSL for untrusted sites</P
5533 > Specifies to which ports HTTP CONNECT requests are allowable.
5546 > A comma-separated list of ports or port ranges (the latter using dashes, with the minimum
5547 defaulting to 0 and the maximum to 65K).
5554 > By default, i.e. if no <TT
5561 > allows HTTP CONNECT requests to all
5565 > if fine-grained control
5566 is desired for some or all destinations.
5569 > The CONNECT methods exists in HTTP to allow access to secure websites
5573 > URLs) through proxies. It works very simply:
5574 the proxy connects to the server on the specified port, and then
5575 short-circuits its connections to the client and to the remote server.
5576 This means CONNECT-enabled proxies can be used as TCP relays very easily.
5582 > relays HTTPS traffic without seeing
5583 the decoded content. Websites can leverage this limitation to circumvent <SPAN
5587 filters. By specifying an invalid port range you can disable HTTPS entirely.
5591 >Example usages:</DT
5602 >+limit-connect{443} # Port 443 is OK.
5603 +limit-connect{80,443} # Ports 80 and 443 are OK.
5604 +limit-connect{-3, 7, 20-100, 500-} # Ports less than 3, 7, 20 to 100 and above 500 are OK.
5605 +limit-connect{-} # All ports are OK
5606 +limit-connect{,} # No HTTPS/SSL traffic is allowed</PRE
5621 NAME="PREVENT-COMPRESSION"
5622 >8.5.27. prevent-compression</A
5627 CLASS="VARIABLELIST"
5633 > Ensure that servers send the content uncompressed, so it can be
5637 HREF="actions-file.html#FILTER"
5647 > Removes the Accept-Encoding header which can be used to ask for compressed transfer.
5667 > More and more websites send their content compressed by default, which
5668 is generally a good idea and saves bandwidth. But the <TT
5671 HREF="actions-file.html#FILTER"
5678 HREF="actions-file.html#DEANIMATE-GIFS"
5682 actions need access to the uncompressed data.
5685 > When compiled with zlib support (available since <SPAN
5688 > 3.0.7), content that should be
5689 filtered is decompressed on-the-fly and you don't have to worry about this action.
5690 If you are using an older <SPAN
5693 > version, or one that hasn't been compiled with zlib
5694 support, this action can be used to convince the server to send the content uncompressed.
5697 > Most text-based instances compress very well, the size is seldom decreased by less than 50%,
5698 for markup-heavy instances like news feeds saving more than 90% of the original size isn't
5702 > Not using compression will therefore slow down the transfer, and you should only
5703 enable this action if you really need it. As of <SPAN
5706 > 3.0.7 it's disabled in all
5707 predefined action settings.
5710 > Note that some (rare) ill-configured sites don't handle requests for uncompressed
5711 documents correctly. Broken PHP applications tend to send an empty document body,
5712 some IIS versions only send the beginning of the content. If you enable
5715 >prevent-compression</TT
5716 > per default, you might want to add
5717 exceptions for those sites. See the example for how to do that.
5721 >Example usage (sections):</DT
5732 ># Selectively turn off compression, and enable a filter
5734 { +filter{tiny-textforms} +prevent-compression }
5735 # Match only these sites
5740 # Or instead, we could set a universal default:
5742 { +prevent-compression }
5745 # Then maybe make exceptions for broken sites:
5747 { -prevent-compression }
5763 NAME="OVERWRITE-LAST-MODIFIED"
5764 >8.5.28. overwrite-last-modified</A
5769 CLASS="VARIABLELIST"
5775 >Prevent yet another way to track the user's steps between sessions.</P
5783 >"Last-Modified:"</SPAN
5784 > HTTP server header or modifies its value.
5797 > One of the keywords: <SPAN
5802 >"reset-to-request-time"</SPAN
5814 > Removing the <SPAN
5816 >"Last-Modified:"</SPAN
5817 > header is useful for filter
5818 testing, where you want to force a real reload instead of getting status
5822 >, which would cause the browser to reuse the old
5823 version of the page.
5829 > option overwrites the value of the
5832 >"Last-Modified:"</SPAN
5833 > header with a randomly chosen time
5834 between the original value and the current time. In theory the server
5835 could send each document with a different <SPAN
5837 >"Last-Modified:"</SPAN
5839 header to track visits without using cookies. <SPAN
5843 makes it impossible and the browser can still revalidate cached documents.
5848 >"reset-to-request-time"</SPAN
5849 > overwrites the value of the
5852 >"Last-Modified:"</SPAN
5853 > header with the current time. You could use
5854 this option together with
5858 HREF="actions-file.html#HIDE-IF-MODIFIED-SINCE"
5859 >hided-if-modified-since</A
5862 to further customize your random range.
5865 > The preferred parameter here is <SPAN
5869 to use, as long as the time settings are more or less correct.
5870 If the server sets the <SPAN
5872 >"Last-Modified:"</SPAN
5873 > header to the time
5874 of the request, the random range becomes zero and the value stays the same.
5875 Therefore you should later randomize it a second time with
5879 HREF="actions-file.html#HIDE-IF-MODIFIED-SINCE"
5880 >hided-if-modified-since</A
5886 > It is also recommended to use this action together with
5890 HREF="actions-file.html#CRUNCH-IF-NONE-MATCH"
5891 >crunch-if-none-match</A
5908 ># Let the browser revalidate without being tracked across sessions
5909 { +hide-if-modified-since{-60} \
5910 +overwrite-last-modified{randomize} \
5911 +crunch-if-none-match}
5928 >8.5.29. redirect</A
5933 CLASS="VARIABLELIST"
5939 > Redirect requests to other sites.
5946 > Convinces the browser that the requested document has been moved
5947 to another location and the browser should get it from there.
5960 > An absolute URL or a single pcrs command.
5967 > Requests to which this action applies are answered with a
5968 HTTP redirect to URLs of your choosing. The new URL is
5969 either provided as parameter, or derived by applying a
5970 single pcrs command to the original URL.
5973 > This action will be ignored if you use it together with
5977 HREF="actions-file.html#BLOCK"
5981 It can be combined with
5985 HREF="actions-file.html#FAST-REDIRECTS"
5986 >fast-redirects{check-decoded-url}</A
5989 to redirect to a decoded version of a rewritten URL.
5992 > Use this action carefully, make sure not to create redirection loops
5993 and be aware that using your own redirects might make it
5994 possible to fingerprint your requests.
5997 > In case of problems with your redirects, or simply to watch
5998 them working, enable <A
5999 HREF="config.html#DEBUG"
6005 >Example usages:</DT
6016 ># Replace example.com's style sheet with another one
6017 { +redirect{http://localhost/css-replacements/example.com.css} }
6018 example.com/stylesheet\.css
6020 # Create a short, easy to remember nickname for a favorite site
6021 # (relies on the browser accept and forward invalid URLs to <SPAN
6025 { +redirect{http://www.privoxy.org/user-manual/actions-file.html} }
6028 # Always use the expanded view for Undeadly.org articles
6029 # (Note the $ at the end of the URL pattern to make sure
6030 # the request for the rewritten URL isn't redirected as well)
6031 {+redirect{s@$@&mode=expanded@}}
6032 undeadly.org/cgi\?action=article&sid=\d*$
6034 # Redirect Google search requests to MSN
6035 {+redirect{s@^http://[^/]*/search\?q=([^&]*).*@http://search.msn.com/results.aspx?q=$1@}}
6038 # Redirect MSN search requests to Yahoo
6039 {+redirect{s@^http://[^/]*/results\.aspx\?q=([^&]*).*@http://search.yahoo.com/search?p=$1@}}
6040 search.msn.com//results\.aspx\?q=
6042 # Redirect remote requests for this manual
6043 # to the local version delivered by Privoxy
6044 {+redirect{s@^http://www@http://config@}}
6045 www.privoxy.org/user-manual/</PRE
6060 NAME="SERVER-HEADER-FILTER"
6061 >8.5.30. server-header-filter</A
6066 CLASS="VARIABLELIST"
6072 > Rewrite or remove single server headers.
6079 > All server headers to which this action applies are filtered on-the-fly
6080 through the specified regular expression based substitutions.
6093 > The name of a server-header filter, as defined in one of the
6095 HREF="filter-file.html"
6104 > Server-header filters are applied to each header on its own, not to
6105 all at once. This makes it easier to diagnose problems, but on the downside
6106 you can't write filters that only change header x if header y's value is z.
6107 You can do that by using tags though.
6110 > Server-header filters are executed after the other header actions have finished
6111 and use their output as input.
6114 > Please refer to the <A
6115 HREF="filter-file.html"
6116 >filter file chapter</A
6118 to learn which server-header filters are available by default, and how to
6123 >Example usage (section):</DT
6134 >{+server-header-filter{html-to-xml}}
6135 example.org/xml-instance-that-is-delivered-as-html
6137 {+server-header-filter{xml-to-html}}
6138 example.org/instance-that-is-delivered-as-xml-but-is-not
6154 NAME="SERVER-HEADER-TAGGER"
6155 >8.5.31. server-header-tagger</A
6160 CLASS="VARIABLELIST"
6166 > Enable or disable filters based on the Content-Type header.
6173 > Server headers to which this action applies are filtered on-the-fly through
6174 the specified regular expression based substitutions, the result is used as
6188 > The name of a server-header tagger, as defined in one of the
6190 HREF="filter-file.html"
6199 > Server-header taggers are applied to each header on its own,
6200 and as the header isn't modified, each tagger <SPAN
6207 > Server-header taggers are executed before all other header actions
6208 that modify server headers. Their tags can be used to control
6209 all of the other server-header actions, the content filters
6210 and the crunch actions (<A
6211 HREF="actions-file.html#REDIRECT"
6215 HREF="actions-file.html#BLOCK"
6220 > Obviously crunching based on tags created by server-header taggers
6221 doesn't prevent the request from showing up in the server's log file.
6225 >Example usage (section):</DT
6236 ># Tag every request with the content type declared by the server
6237 {+server-header-tagger{content-type}}
6254 NAME="SESSION-COOKIES-ONLY"
6255 >8.5.32. session-cookies-only</A
6260 CLASS="VARIABLELIST"
6266 > Allow only temporary <SPAN
6269 > cookies (for the current
6270 browser session <SPAN
6288 >"Set-Cookie:"</SPAN
6290 server headers. Most browsers will not store such cookies permanently and
6291 forget them in between sessions.
6311 > This is less strict than <TT
6314 HREF="actions-file.html#CRUNCH-INCOMING-COOKIES"
6315 >crunch-incoming-cookies</A
6321 HREF="actions-file.html#CRUNCH-OUTGOING-COOKIES"
6322 >crunch-outgoing-cookies</A
6324 > and allows you to browse
6325 websites that insist or rely on setting cookies, without compromising your privacy too badly.
6328 > Most browsers will not permanently store cookies that have been processed by
6331 >session-cookies-only</TT
6332 > and will forget about them between sessions.
6333 This makes profiling cookies useless, but won't break sites which require cookies so
6334 that you can log in for transactions. This is generally turned on for all
6335 sites, and is the recommended setting.
6346 >session-cookies-only</TT
6351 HREF="actions-file.html#CRUNCH-INCOMING-COOKIES"
6352 >crunch-incoming-cookies</A
6358 HREF="actions-file.html#CRUNCH-OUTGOING-COOKIES"
6359 >crunch-outgoing-cookies</A
6361 >. If you do, cookies
6362 will be plainly killed.
6365 > Note that it is up to the browser how it handles such cookies without an <SPAN
6369 field. If you use an exotic browser, you might want to try it out to be sure.
6372 > This setting also has no effect on cookies that may have been stored
6373 previously by the browser before starting <SPAN
6377 These would have to be removed manually.
6385 HREF="actions-file.html#FILTER-CONTENT-COOKIES"
6386 >content-cookies filter</A
6388 to block some types of cookies. Content cookies are not effected by
6391 >session-cookies-only</TT
6407 >+session-cookies-only</PRE
6422 NAME="SET-IMAGE-BLOCKER"
6423 >8.5.33. set-image-blocker</A
6428 CLASS="VARIABLELIST"
6434 >Choose the replacement for blocked images</P
6440 > This action alone doesn't do anything noticeable. If <SPAN
6450 HREF="actions-file.html#BLOCK"
6462 HREF="actions-file.html#HANDLE-AS-IMAGE"
6472 apply, i.e. if the request is to be blocked as an image,
6479 > the parameter of this action decides what will be
6480 sent as a replacement.
6500 > to send a built-in checkerboard pattern image. The image is visually
6501 decent, scales very well, and makes it obvious where banners were busted.
6509 > to send a built-in transparent image. This makes banners disappear
6510 completely, but makes it hard to detect where <SPAN
6514 images on a given page and complicates troubleshooting if <SPAN
6518 has blocked innocent images, like navigation icons.
6532 send a redirect to <TT
6538 to any image anywhere, even in your local filesystem via <SPAN
6542 (But note that not all browsers support redirecting to a local file system).
6545 > A good application of redirects is to use special <SPAN
6549 URLs, which send the built-in images, as <TT
6555 This has the same visual effect as specifying <SPAN
6562 the first place, but enables your browser to cache the replacement image, instead of requesting
6563 it over and over again.
6572 > The URLs for the built-in images are <SPAN
6574 >"http://config.privoxy.org/send-banner?type=<TT
6595 > There is a third (advanced) type, called <SPAN
6607 >set-image-blocker</TT
6608 >, but meant for use from <A
6609 HREF="filter-file.html"
6612 Auto will select the type of image that would have applied to the referring page, had it been an image.
6630 >+set-image-blocker{pattern}</PRE
6637 > Redirect to the BSD daemon:
6648 >+set-image-blocker{http://www.freebsd.org/gifs/dae_up3.gif}</PRE
6655 > Redirect to the built-in pattern for better caching:
6666 >+set-image-blocker{http://config.privoxy.org/send-banner?type=pattern}</PRE
6685 > Note that many of these actions have the potential to cause a page to
6686 misbehave, possibly even not to display at all. There are many ways
6687 a site designer may choose to design his site, and what HTTP header
6688 content, and other criteria, he may depend on. There is no way to have hard
6689 and fast rules for all sites. See the <A
6690 HREF="appendix.html#ACTIONSANAT"
6692 > for a brief example on troubleshooting
6715 >, can be defined by combining other actions.
6716 These can in turn be invoked just like the built-in actions.
6717 Currently, an alias name can contain any character except space, tab,
6735 > that you only use <SPAN
6755 Alias names are not case sensitive, and are not required to start with a
6762 > sign, since they are merely textually
6765 > Aliases can be used throughout the actions file, but they <SPAN
6770 defined in a special section at the top of the file!</I
6773 And there can only be one such section per actions file. Each actions file may
6774 have its own alias section, and the aliases defined in it are only visible
6775 within that file.</P
6777 > There are two main reasons to use aliases: One is to save typing for frequently
6778 used combinations of actions, the other one is a gain in flexibility: If you
6779 decide once how you want to handle shops by defining an alias called
6783 >, you can later change your policy on shops in
6790 > place, and your changes will take effect everywhere
6791 in the actions file where the <SPAN
6794 > alias is used. Calling aliases
6795 by their purpose also makes your actions files more readable.</P
6797 > Currently, there is one big drawback to using aliases, though:
6801 >'s built-in web-based action file
6802 editor honors aliases when reading the actions files, but it expands
6803 them before writing. So the effects of your aliases are of course preserved,
6804 but the aliases themselves are lost when you edit sections that use aliases
6807 > Now let's define some aliases...</P
6817 > # Useful custom aliases we can use later.
6819 # Note the (required!) section header line and that this section
6820 # must be at the top of the actions file!
6824 # These aliases just save typing later:
6825 # (Note that some already use other aliases!)
6827 +crunch-all-cookies = +<A
6828 HREF="actions-file.html#CRUNCH-INCOMING-COOKIES"
6829 >crunch-incoming-cookies</A
6831 HREF="actions-file.html#CRUNCH-OUTGOING-COOKIES"
6832 >crunch-outgoing-cookies</A
6834 -crunch-all-cookies = -<A
6835 HREF="actions-file.html#CRUNCH-INCOMING-COOKIES"
6836 >crunch-incoming-cookies</A
6838 HREF="actions-file.html#CRUNCH-OUTGOING-COOKIES"
6839 >crunch-outgoing-cookies</A
6841 +block-as-image = +block{Blocked image.} +handle-as-image
6842 allow-all-cookies = -crunch-all-cookies -<A
6843 HREF="actions-file.html#SESSION-COOKIES-ONLY"
6844 >session-cookies-only</A
6846 HREF="actions-file.html#FILTER-CONTENT-COOKIES"
6847 >filter{content-cookies}</A
6850 # These aliases define combinations of actions
6851 # that are useful for certain types of sites:
6854 HREF="actions-file.html#BLOCK"
6857 HREF="actions-file.html#FILTER"
6859 > -crunch-all-cookies -<A
6860 HREF="actions-file.html#FAST-REDIRECTS"
6863 HREF="actions-file.html#HIDE-REFERER"
6866 HREF="actions-file.html#PREVENT-COMPRESSION"
6867 >prevent-compression</A
6870 shop = -crunch-all-cookies -<A
6871 HREF="actions-file.html#FILTER-ALL-POPUPS"
6872 >filter{all-popups}</A
6875 # Short names for other aliases, for really lazy people ;-)
6877 c0 = +crunch-all-cookies
6878 c1 = -crunch-all-cookies</PRE
6884 > ...and put them to use. These sections would appear in the lower part of an
6885 actions file and define exceptions to the default actions (as specified further
6899 > # These sites are either very complex or very keen on
6900 # user data and require minimal interference to work:
6903 .office.microsoft.com
6904 .windowsupdate.microsoft.com
6905 # Gmail is really mail.google.com, not gmail.com
6909 # Allow cookies (for setting and retrieving your customer data)
6913 .worldpay.com # for quietpc.com
6916 # These shops require pop-ups:
6918 {-filter{all-popups} -filter{unsolicited-popups}}
6920 .overclockers.co.uk</PRE
6926 > Aliases like <SPAN
6932 > are typically used for
6936 > sites that require more than one action to be disabled
6937 in order to function properly.</P
6945 >8.7. Actions Files Tutorial</A
6948 > The above chapters have shown <A
6949 HREF="actions-file.html"
6950 >which actions files
6951 there are and how they are organized</A
6952 >, how actions are <A
6953 HREF="actions-file.html#ACTIONS"
6956 HREF="actions-file.html#ACTIONS-APPLY"
6960 HREF="actions-file.html#AF-PATTERNS"
6964 HREF="actions-file.html#ALIASES"
6966 >. Now, let's look at an
6974 file and see how all these pieces come together:</P
6981 >8.7.1. default.action</A
6984 >Every config file should start with a short comment stating its purpose:</P
6994 ># Sample default.action file <ijbswa-developers@lists.sourceforge.net></PRE
7000 >Then, since this is the <TT
7004 first section is a special section for internal use that you needn't
7005 change or worry about:</P
7015 >##########################################################################
7016 # Settings -- Don't change! For internal Privoxy use ONLY.
7017 ##########################################################################
7020 for-privoxy-version=3.0</PRE
7026 >After that comes the (optional) alias section. We'll use the example
7027 section from the above <A
7028 HREF="actions-file.html#ALIASES"
7029 >chapter on aliases</A
7031 that also explains why and how aliases are used:</P
7041 >##########################################################################
7043 ##########################################################################
7046 # These aliases just save typing later:
7047 # (Note that some already use other aliases!)
7049 +crunch-all-cookies = +<A
7050 HREF="actions-file.html#CRUNCH-INCOMING-COOKIES"
7051 >crunch-incoming-cookies</A
7053 HREF="actions-file.html#CRUNCH-OUTGOING-COOKIES"
7054 >crunch-outgoing-cookies</A
7056 -crunch-all-cookies = -<A
7057 HREF="actions-file.html#CRUNCH-INCOMING-COOKIES"
7058 >crunch-incoming-cookies</A
7060 HREF="actions-file.html#CRUNCH-OUTGOING-COOKIES"
7061 >crunch-outgoing-cookies</A
7063 +block-as-image = +block{Blocked image.} +handle-as-image
7064 mercy-for-cookies = -crunch-all-cookies -<A
7065 HREF="actions-file.html#SESSION-COOKIES-ONLY"
7066 >session-cookies-only</A
7068 HREF="actions-file.html#FILTER-CONTENT-COOKIES"
7069 >filter{content-cookies}</A
7072 # These aliases define combinations of actions
7073 # that are useful for certain types of sites:
7076 HREF="actions-file.html#BLOCK"
7079 HREF="actions-file.html#FILTER"
7081 > -crunch-all-cookies -<A
7082 HREF="actions-file.html#FAST-REDIRECTS"
7085 HREF="actions-file.html#HIDE-REFERER"
7088 shop = -crunch-all-cookies -<A
7089 HREF="actions-file.html#FILTER-ALL-POPUPS"
7090 >filter{all-popups}</A
7097 > Now come the regular sections, i.e. sets of actions, accompanied
7098 by URL patterns to which they apply. Remember <SPAN
7103 are disabled when matching starts</I
7105 >, so we have to explicitly
7106 enable the ones we want.</P
7108 > The first regular section is probably the most important. It has only
7117 HREF="actions-file.html#AF-PATTERNS"
7118 >matches all URLs</A
7120 set of actions used in this <SPAN
7128 be applied to all requests as a start</I
7130 >. It can be partly or
7131 wholly overridden by later matches further down this file, or in user.action,
7132 but it will still be largely responsible for your overall browsing
7135 > Again, at the start of matching, all actions are disabled, so there is
7136 no need to disable any actions here. (Remember: a <SPAN
7140 preceding the action name enables the action, a <SPAN
7144 Also note how this long line has been made more readable by splitting it into
7145 multiple lines with line continuation.</P
7155 >##########################################################################
7156 # "Defaults" section:
7157 ##########################################################################
7160 HREF="actions-file.html#CHANGE-X-FORWARDED-FOR"
7161 >change-x-forwarded-for{block}</A
7164 HREF="actions-file.html#DEANIMATE-GIFS"
7168 HREF="actions-file.html#FILTER-HTML-ANNOYANCES"
7169 >filter{html-annoyances}</A
7172 HREF="actions-file.html#FILTER-REFRESH-TAGS"
7173 >filter{refresh-tags}</A
7176 HREF="actions-file.html#FILTER-WEBBUGS"
7180 HREF="actions-file.html#FILTER-IE-EXPLOITS"
7181 >filter{ie-exploits}</A
7184 HREF="actions-file.html#HIDE-FROM-HEADER"
7185 >hide-from-header{block}</A
7188 HREF="actions-file.html#HIDE-REFERER"
7189 >hide-referrer{forge}</A
7192 HREF="actions-file.html#PREVENT-COMPRESSION"
7193 >prevent-compression</A
7196 HREF="actions-file.html#SESSION-COOKIES-ONLY"
7197 >session-cookies-only</A
7200 HREF="actions-file.html#SET-IMAGE-BLOCKER"
7201 >set-image-blocker{pattern}</A
7204 / # forward slash will match *all* potential URL patterns.</PRE
7210 > The default behavior is now set.
7213 > The first of our specialized sections is concerned with <SPAN
7217 sites, i.e. sites that require minimum interference, because they are either
7218 very complex or very keen on tracking you (and have mechanisms in place that
7219 make them unusable for people who avoid being tracked). We will simply use
7223 > alias instead of stating the list
7224 of actions explicitly:</P
7234 >##########################################################################
7235 # Exceptions for sites that'll break under the default action set:
7236 ##########################################################################
7238 # "Fragile" Use a minimum set of actions for these sites (see alias above):
7241 .office.microsoft.com # surprise, surprise!
7242 .windowsupdate.microsoft.com
7243 mail.google.com</PRE
7249 > Shopping sites are not as fragile, but they typically
7250 require cookies to log in, and pop-up windows for shopping
7251 carts or item details. Again, we'll use a pre-defined alias:</P
7265 .worldpay.com # for quietpc.com
7276 HREF="actions-file.html#FAST-REDIRECTS"
7280 action, which we enabled per default above, breaks some sites. So disable
7281 it for popular sites where we know it misbehaves:</P
7292 HREF="actions-file.html#FAST-REDIRECTS"
7298 .altavista.com/.*(like|url|link):http
7299 .altavista.com/trans.*urltext=http
7306 > It is important that <SPAN
7310 URLs belong to images, so that <SPAN
7317 be blocked, a substitute image can be sent, rather than an HTML page.
7318 Contacting the remote site to find out is not an option, since it
7319 would destroy the loading time advantage of banner blocking, and it
7320 would feed the advertisers (in terms of money <SPAN
7327 information). We can mark any URL as an image with the <TT
7330 HREF="actions-file.html#HANDLE-AS-IMAGE"
7334 and marking all URLs that end in a known image file extension is a
7345 >##########################################################################
7347 ##########################################################################
7349 # Define which file types will be treated as images, in case they get
7350 # blocked further down this file:
7353 HREF="actions-file.html#HANDLE-AS-IMAGE"
7356 /.*\.(gif|jpe?g|png|bmp|ico)$</PRE
7362 > And then there are known banner sources. They often use scripts to
7363 generate the banners, so it won't be visible from the URL that the
7364 request is for an image. Hence we block them <SPAN
7371 mark them as images in one go, with the help of our
7374 >+block-as-image</TT
7375 > alias defined above. (We could of
7376 course just as well use <TT
7379 HREF="actions-file.html#BLOCK"
7383 HREF="actions-file.html#HANDLE-AS-IMAGE"
7387 Remember that the type of the replacement image is chosen by the
7391 HREF="actions-file.html#SET-IMAGE-BLOCKER"
7392 >set-image-blocker</A
7395 action. Since all URLs have matched the default section with its
7399 HREF="actions-file.html#SET-IMAGE-BLOCKER"
7400 >set-image-blocker</A
7403 action before, it still applies and needn't be repeated:</P
7413 ># Known ad generators:
7418 .ad.*.doubleclick.net
7419 .a.yimg.com/(?:(?!/i/).)*$
7420 .a[0-9].yimg.com/(?:(?!/i/).)*$
7428 > One of the most important jobs of <SPAN
7432 is to block banners. Many of these can be <SPAN
7439 HREF="actions-file.html#FILTER"
7441 >{banners-by-size}</TT
7443 action, which we enabled above, and which deletes the references to banner
7444 images from the pages while they are loaded, so the browser doesn't request
7445 them anymore, and hence they don't need to be blocked here. But this naturally
7446 doesn't catch all banners, and some people choose not to use filters, so we
7447 need a comprehensive list of patterns for banner URLs here, and apply the
7451 HREF="actions-file.html#BLOCK"
7454 > action to them.</P
7456 > First comes many generic patterns, which do most of the work, by
7457 matching typical domain and path name components of banners. Then comes
7458 a list of individual patterns for specific sites, which is omitted here
7459 to keep the example short:</P
7469 >##########################################################################
7470 # Block these fine banners:
7471 ##########################################################################
7473 HREF="actions-file.html#BLOCK"
7474 >+block{Banner ads.}</A
7483 /.*count(er)?\.(pl|cgi|exe|dll|asp|php[34]?)
7484 /(?:.*/)?(publicite|werbung|rekla(ma|me|am)|annonse|maino(kset|nta|s)?)/
7486 # Site-specific patterns (abbreviated):
7494 > It's quite remarkable how many advertisers actually call their banner
7500 >.com, or call the directory
7501 in which the banners are stored simply <SPAN
7505 generic patterns are surprisingly effective.</P
7507 > But being very generic, they necessarily also catch URLs that we don't want
7508 to block. The pattern <TT
7520 >.nasty-corp.com"</SPAN
7530 >.sourcefroge.net"</SPAN
7540 >l.some-provider.net."</SPAN
7542 well-known exceptions to the <TT
7545 HREF="actions-file.html#BLOCK"
7551 > Note that these are exceptions to exceptions from the default! Consider the URL
7554 >"downloads.sourcefroge.net"</SPAN
7555 >: Initially, all actions are deactivated,
7556 so it wouldn't get blocked. Then comes the defaults section, which matches the
7557 URL, but just deactivates the <TT
7560 HREF="actions-file.html#BLOCK"
7564 action once again. Then it matches <TT
7567 >, an exception to the
7568 general non-blocking policy, and suddenly
7572 HREF="actions-file.html#BLOCK"
7575 > applies. And now, it'll match
7582 HREF="actions-file.html#BLOCK"
7586 applies, so (unless it matches <SPAN
7592 > further down) it ends up
7596 HREF="actions-file.html#BLOCK"
7599 > action applying.</P
7609 >##########################################################################
7610 # Save some innocent victims of the above generic block patterns:
7611 ##########################################################################
7616 HREF="actions-file.html#BLOCK"
7619 adv[io]*. # (for advogato.org and advice.*)
7620 adsl. # (has nothing to do with ads)
7621 adobe. # (has nothing to do with ads either)
7622 ad[ud]*. # (adult.* and add.*)
7623 .edu # (universities don't host banners (yet!))
7624 .*loads. # (downloads, uploads etc)
7632 www.globalintersec.com/adv # (adv = advanced)
7633 www.ugu.com/sui/ugu/adv</PRE
7639 > Filtering source code can have nasty side effects,
7640 so make an exception for our friends at sourceforge.net,
7641 and all paths with <SPAN
7644 > in them. Note that
7648 HREF="actions-file.html#FILTER"
7658 > filters in one fell swoop!</P
7668 ># Don't filter code!
7671 HREF="actions-file.html#FILTER"
7678 .sourceforge.net</PRE
7687 > is of course much more
7688 comprehensive, but we hope this example made clear how it works.</P
7696 >8.7.2. user.action</A
7699 > So far we are painting with a broad brush by setting general policies,
7700 which would be a reasonable starting point for many people. Now,
7701 you might want to be more specific and have customized rules that
7702 are more suitable to your personal habits and preferences. These would
7703 be for narrowly defined situations like your ISP or your bank, and should
7707 >, which is parsed after all other
7708 actions files and hence has the last word, over-riding any previously
7709 defined actions. <TT
7719 > place for your personal settings, since
7723 > is actively maintained by the
7727 > developers and you'll probably want
7728 to install updated versions from time to time.</P
7730 > So let's look at a few examples of things that one might typically do in
7744 ># My user.action file. <fred@example.com></PRE
7751 HREF="actions-file.html#ALIASES"
7753 > are local to the actions
7754 file that they are defined in, you can't use the ones from
7758 >, unless you repeat them here:</P
7768 ># Aliases are local to the file they are defined in.
7769 # (Re-)define aliases for this file:
7773 # These aliases just save typing later, and the alias names should
7774 # be self explanatory.
7776 +crunch-all-cookies = +crunch-incoming-cookies +crunch-outgoing-cookies
7777 -crunch-all-cookies = -crunch-incoming-cookies -crunch-outgoing-cookies
7778 allow-all-cookies = -crunch-all-cookies -session-cookies-only
7779 allow-popups = -filter{all-popups}
7780 +block-as-image = +block{Blocked as image.} +handle-as-image
7781 -block-as-image = -block
7783 # These aliases define combinations of actions that are useful for
7784 # certain types of sites:
7786 fragile = -block -crunch-all-cookies -filter -fast-redirects -hide-referrer
7787 shop = -crunch-all-cookies allow-popups
7789 # Allow ads for selected useful free sites:
7791 allow-ads = -block -filter{banners-by-size} -filter{banners-by-link}
7793 # Alias for specific file types that are text, but might have conflicting
7794 # MIME types. We want the browser to force these to be text documents.
7795 handle-as-text = -<A
7796 HREF="actions-file.html#FILTER"
7799 HREF="actions-file.html#CONTENT-TYPE-OVERWRITE"
7800 >content-type-overwrite{text/plain}</A
7802 HREF="actions-file.html#FORCE-TEXT-MODE"
7805 HREF="actions-file.html#HIDE-CONTENT-DISPOSITION"
7806 >hide-content-disposition</A
7813 > Say you have accounts on some sites that you visit regularly, and
7814 you don't want to have to log in manually each time. So you'd like
7815 to allow persistent cookies for these sites. The
7818 >allow-all-cookies</TT
7819 > alias defined above does exactly
7820 that, i.e. it disables crunching of cookies in any direction, and the
7821 processing of cookies to make them only temporary.</P
7831 >{ allow-all-cookies }
7841 > Your bank is allergic to some filter, but you don't know which, so you disable them all:</P
7852 HREF="actions-file.html#FILTER"
7855 .your-home-banking-site.com</PRE
7861 > Some file types you may not want to filter for various reasons:</P
7871 ># Technical documentation is likely to contain strings that might
7872 # erroneously get altered by the JavaScript-oriented filters:
7877 # And this stupid host sends streaming video with a wrong MIME type,
7878 # so that Privoxy thinks it is getting HTML and starts filtering:
7880 stupid-server.example.com/</PRE
7886 > Example of a simple <A
7887 HREF="actions-file.html#BLOCK"
7889 > action. Say you've
7890 seen an ad on your favourite page on example.com that you want to get rid of.
7891 You have right-clicked the image, selected <SPAN
7893 >"copy image location"</SPAN
7895 and pasted the URL below while removing the leading http://, into a
7899 > section. Note that <TT
7903 > need not be specified, since all URLs ending in
7907 > will be tagged as images by the general rules as set
7908 in default.action anyway:</P
7919 HREF="actions-file.html#BLOCK"
7922 www.example.com/nasty-ads/sponsor\.gif
7923 another.example.net/more/junk/here/</PRE
7929 > The URLs of dynamically generated banners, especially from large banner
7930 farms, often don't use the well-known image file name extensions, which
7931 makes it impossible for <SPAN
7935 the file type just by looking at the URL.
7938 >+block-as-image</TT
7939 > alias defined above for
7941 Note that objects which match this rule but then turn out NOT to be an
7942 image are typically rendered as a <SPAN
7944 >"broken image"</SPAN
7946 browser. Use cautiously.</P
7956 >{ +block-as-image }
7966 > Now you noticed that the default configuration breaks Forbes Magazine,
7967 but you were too lazy to find out which action is the culprit, and you
7968 were again too lazy to give <A
7972 you just used the <TT
7975 > alias on the site, and
7982 > -- it worked. The <TT
7986 aliases disables those actions that are most likely to break a site. Also,
7987 good for testing purposes to see if it is <SPAN
7991 that is causing the problem or not. We later find other regular sites
7992 that misbehave, and add those to our personalized list of troublemakers:</P
8011 > You like the <SPAN
8014 > text replacements in <TT
8018 but it is disabled in the distributed actions file.
8019 So you'd like to turn it on in your private,
8020 update-safe config, once and for all:</P
8031 HREF="actions-file.html#FILTER-FUN"
8034 / # For ALL sites!</PRE
8040 > Note that the above is not really a good idea: There are exceptions
8041 to the filters in <TT
8045 really shouldn't be filtered, like code on CVS->Web interfaces. Since
8049 > has the last word, these exceptions
8050 won't be valid for the <SPAN
8053 > filtering specified here.</P
8055 > You might also worry about how your favourite free websites are
8056 funded, and find that they rely on displaying banner advertisements
8057 to survive. So you might want to specifically allow banners for those
8058 sites that you feel provide value to you:</P
8080 > has been aliased to
8084 HREF="actions-file.html#BLOCK"
8091 HREF="actions-file.html#FILTER-BANNERS-BY-SIZE"
8092 >filter{banners-by-size}</A
8098 HREF="actions-file.html#FILTER-BANNERS-BY-LINK"
8099 >filter{banners-by-link}</A
8103 > Invoke another alias here to force an over-ride of the MIME type <TT
8105 > application/x-sh</TT
8106 > which typically would open a download type
8107 dialog. In my case, I want to look at the shell script, and then I can save
8108 it should I choose to.</P
8128 > is generally the best place to define
8129 exceptions and additions to the default policies of
8133 >. Some actions are safe to have their
8134 default policies set here though. So let's set a default policy to have a
8138 > image as opposed to the checkerboard pattern for
8148 > of course matches all URL
8149 paths and patterns:</P
8160 HREF="actions-file.html#SET-IMAGE-BLOCKER"
8161 >set-image-blocker{blank}</A
8176 SUMMARY="Footer navigation table"
8205 HREF="filter-file.html"
8215 >The Main Configuration File</TD