1 <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN""http://www.w3.org/TR/html4/loose.dtd">
8 CONTENT="Modular DocBook HTML Stylesheet Version 1.79"><LINK
10 TITLE="Privoxy 3.0.7 User Manual"
11 HREF="index.html"><LINK
13 TITLE="The Main Configuration File"
14 HREF="config.html"><LINK
17 HREF="filter-file.html"><LINK
21 <LINK REL="STYLESHEET" TYPE="text/css" HREF="p_doc.css">
33 SUMMARY="Header navigation table"
42 >Privoxy 3.0.7 User Manual</TH
64 HREF="filter-file.html"
82 > The actions files are used to define what <SPAN
92 > takes for which URLs, and thus determines
93 how ad images, cookies and various other aspects of HTTP content and
94 transactions are handled, and on which sites (or even parts thereof).
95 There are a number of such actions, with a wide range of functionality.
96 Each action does something a little different.
97 These actions give us a veritable arsenal of tools with which to exert
98 our control, preferences and independence. Actions can be combined so that
99 their effects are aggregated when applied against a given set of URLs.</P
102 are three action files included with <SPAN
117 > - is the primary action file
118 that sets the initial values for all actions. It is intended to
119 provide a base level of functionality for
123 > array of features. So it is
124 a set of broad rules that should work reasonably well as-is for most users.
125 This is the file that the developers are keeping updated, and <A
126 HREF="installation.html#INSTALLATION-KEEPUPDATED"
127 >making available to users</A
129 The user's preferences as set in <TT
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.
163 > - is used only by the web based editor
165 HREF="http://config.privoxy.org/edit-actions-list?f=default"
167 > http://config.privoxy.org/edit-actions-list?f=default</A
169 to set various pre-defined sets of rules for the default actions section
181 >Set to Cautious</SPAN
187 >Set to Advanced</SPAN
191 > These have increasing levels of aggressiveness <SPAN
196 influence on your browsing unless you select them explicitly in the
199 >. A default installation should be pre-set to
203 > (versions prior to 3.0.5 were set to
207 >). New users should try this for a while before
208 adjusting the settings to more aggressive levels. The more aggressive
209 the settings, then the more likelihood there is of problems such as sites
210 not working as they should.
216 > button allows you to turn each
217 action on/off individually for fine-tuning. The <SPAN
221 button changes the actions list to low/safe settings which will activate
222 ad blocking and a minimal set of <SPAN
225 >'s features, and subsequently
226 there will be less of a chance for accidental problems. The
230 > button sets the list to a medium level of
231 other features and a low level set of privacy features. The
235 > button sets the list to a high level of
236 ad blocking and medium level of privacy. See the chart below. The latter
237 three buttons over-ride any changes via with the
241 > button. More fine-tuning can be done in the
242 lower sections of this internal page.
245 > It is not recommend to edit the <TT
252 > The default profiles, and their associated actions, as pre-defined in
266 >Table 1. Default Configurations</B
296 >Ad-blocking Aggressiveness</TD
306 >Ad-filtering by size</TD
316 >Ad-filtering by link</TD
336 >Privacy Features</TD
366 >GIF de-animation</TD
396 >JavaScript taming</TD
416 >Image tag reordering</TD
434 > The list of actions files to be used are defined in the main configuration
435 file, and are processed in the order they are defined (e.g.
439 > is typically processed before
443 >). The content of these can all be viewed and
445 HREF="http://config.privoxy.org/show-status"
447 >http://config.privoxy.org/show-status</A
449 The over-riding principle when applying actions, is that the last action that
450 matches a given URL wins. The broadest, most general rules go first
455 followed by any exceptions (typically also in
459 >), which are then followed lastly by any
460 local preferences (typically in <SPAN
476 > An actions file typically has multiple sections. If you want to use
480 > in an actions file, you have to place the (optional)
482 HREF="actions-file.html#ALIASES"
484 > at the top of that file.
485 Then comes the default set of rules which will apply universally to all
486 sites and pages (be <SPAN
496 > or any other actions file after
500 >, because it will override the result
501 from consulting any previous file). And then below that,
502 exceptions to the defined universal policies. You can regard
506 > as an appendix to <TT
510 with the advantage that it is a separate file, which makes preserving your
511 personal settings across <SPAN
514 > upgrades easier.</P
517 Actions can be used to block anything you want, including ads, banners, or
518 just some obnoxious URL whose content you would rather not see. Cookies can be accepted
519 or rejected, or accepted only during the current browser session (i.e. not
520 written to disk), content can be modified, some JavaScripts tamed, user-tracking
521 fooled, and much more. See below for a <A
522 HREF="actions-file.html#ACTIONS"
532 >8.1. Finding the Right Mix</A
536 HREF="actions-file.html#ACTIONS"
538 >, like cookie suppression
539 or script disabling, may render some sites unusable that rely on these
540 techniques to work properly. Finding the right mix of actions is not always easy and
541 certainly a matter of personal taste. And, things can always change, requiring
542 refinements in the configuration. In general, it can be said that the more
546 > your default settings (in the top section of the
547 actions file) are, the more exceptions for <SPAN
551 will have to make later. If, for example, you want to crunch all cookies per
552 default, you'll have to make exceptions from that rule for sites that you
553 regularly use and that require cookies for actually useful purposes, like maybe
554 your bank, favorite shop, or newspaper.</P
556 > We have tried to provide you with reasonable rules to start from in the
557 distribution actions files. But there is no general rule of thumb on these
558 things. There just are too many variables, and sites are constantly changing.
559 Sooner or later you will want to change the rules (and read this chapter again :).</P
570 > The easiest way to edit the actions files is with a browser by
571 using our browser-based editor, which can be reached from <A
572 HREF="http://config.privoxy.org/show-status"
574 >http://config.privoxy.org/show-status</A
576 Note: the config file option <A
577 HREF="config.html#ENABLE-EDIT-ACTIONS"
578 >enable-edit-actions</A
579 > must be enabled for
580 this to work. The editor allows both fine-grained control over every single
581 feature on a per-URL basis, and easy choosing from wholesale sets of defaults
592 >. Warning: the <SPAN
596 aggressive, and will be more likely to cause problems for some sites.
597 Experienced users only!
600 > If you prefer plain text editing to GUIs, you can of course also directly edit the
601 the actions files with your favorite text editor. Look at
605 > which is richly commented with many
614 >8.3. How Actions are Applied to Requests</A
617 > Actions files are divided into sections. There are special sections,
621 HREF="actions-file.html#ALIASES"
624 > sections which will
625 be discussed later. For now let's concentrate on regular sections: They have a
626 heading line (often split up to multiple lines for readability) which consist
627 of a list of actions, separated by whitespace and enclosed in curly braces.
628 Below that, there is a list of URL and tag patterns, each on a separate line.</P
630 > To determine which actions apply to a request, the URL of the request is
631 compared to all URL patterns in each <SPAN
635 Every time it matches, the list of applicable actions for the request is
636 incrementally updated, using the heading of the section in which the
637 pattern is located. The same is done again for tags and tag patterns later on.</P
639 > If multiple applying sections set the same action differently,
640 the last match wins. If not, the effects are aggregated.
641 E.g. a URL might match a regular section with a heading line of <TT
645 HREF="actions-file.html#HANDLE-AS-IMAGE"
649 then later another one with just <TT
653 HREF="actions-file.html#BLOCK"
663 > actions to apply. And there may well be
664 cases where you will want to combine actions together. Such a section then
682 # Block these as if they were images. Send no block page.
684 media.example.com/.*banners
685 .example.com/images/ads/</PRE
692 > You can trace this process for URL patterns and any given URL by visiting <A
693 HREF="http://config.privoxy.org/show-url-info"
695 >http://config.privoxy.org/show-url-info</A
698 > Examples and more detail on this is provided in the Appendix, <A
699 HREF="appendix.html#ACTIONSANAT"
700 > Troubleshooting: Anatomy of an Action</A
720 to determine what <SPAN
726 > might apply to which sites and
727 pages your browser attempts to access. These <SPAN
737 > matching to achieve a high degree of
738 flexibility. This allows one expression to be expanded and potentially match
739 against many similar patterns.</P
741 > Generally, an URL pattern has the form
744 ><domain>/<path></TT
748 ><domain></TT
753 optional. (This is why the special <TT
756 > pattern matches all
757 URLs). Note that the protocol portion of the URL pattern (e.g.
768 the pattern. This is assumed already!</P
770 > The pattern matching syntax is different for the domain and path parts of
771 the URL. The domain part uses a simple globbing type matching technique,
772 while the path part uses a more flexible
774 HREF="http://en.wikipedia.org/wiki/Regular_expressions"
779 Expressions (PCRE)"</SPAN
790 >www.example.com/</TT
794 > is a domain-only pattern and will match any request to <TT
798 regardless of which document on that server is requested. So ALL pages in
799 this domain would be covered by the scope of this action. Note that a
803 > is different and would NOT match.
813 > means exactly the same. For domain-only patterns, the trailing <TT
823 >www.example.com/index.html$</TT
827 > matches all the documents on <TT
831 whose name starts with <TT
840 >www.example.com/index.html$</TT
844 > matches only the single document <TT
861 > matches the document <TT
864 >, regardless of the domain,
871 > web server anywhere.
881 > matches nothing, since it would be interpreted as a domain name and
882 there is no top-level domain called <TT
897 >8.4.1. The Domain Pattern</A
900 > The matching of the domain part offers some flexible options: if the
901 domain starts or ends with a dot, it becomes unanchored at that end.
915 > matches any domain that <SPAN
935 > matches any domain that <SPAN
955 > matches any domain that <SPAN
965 And, by the way, also included would be any files or documents that exist
966 within that domain since no path limitations are specified. (Correctly
967 speaking: It matches any FQDN that contains <TT
971 a domain.) This might be <TT
981 >www.example.net/cgi/testing.pl</TT
982 > for instance. All these
989 > Additionally, there are wild-cards that you can use in the domain names
990 themselves. These work similarly to shell globbing type wild-cards:
994 > represents zero or more arbitrary characters (this is
997 HREF="http://en.wikipedia.org/wiki/Regular_expressions"
1004 > based syntax of <SPAN
1011 > represents any single character (this is equivalent to the
1012 regular expression syntax of a simple <SPAN
1015 >), and you can define
1018 >"character classes"</SPAN
1019 > in square brackets which is similar to
1020 the same regular expression technique. All of this can be freely mixed:</P
1024 CLASS="VARIABLELIST"
1029 >ad*.example.com</TT
1035 >"adserver.example.com"</SPAN
1039 >"ads.example.com"</SPAN
1040 >, etc but not <SPAN
1042 >"sfads.example.com"</SPAN
1049 >*ad*.example.com</TT
1053 > matches all of the above, and then some.
1069 >pictures.epix.com</TT
1072 >a.b.c.d.e.upix.com</TT
1079 >www[1-9a-ez].example.c*</TT
1085 >www1.example.com</TT
1089 >www4.example.cc</TT
1092 >wwwd.example.cy</TT
1096 >wwwz.example.com</TT
1106 >wwww.example.com</TT
1113 > While flexible, this is not the sophistication of full regular expression based syntax.</P
1121 >8.4.2. The Path Pattern</A
1127 > uses Perl compatible (PCRE)
1129 HREF="http://en.wikipedia.org/wiki/Regular_expressions"
1138 HREF="http://www.pcre.org/"
1142 matching the path portion (after the slash), and is thus more flexible.</P
1145 HREF="appendix.html#REGEX"
1147 > with a brief quick-start into regular
1148 expressions, and full (very technical) documentation on PCRE regex syntax is available on-line
1150 HREF="http://www.pcre.org/man.txt"
1152 >http://www.pcre.org/man.txt</A
1154 You might also find the Perl man page on regular expressions (<TT
1158 useful, which is available on-line at <A
1159 HREF="http://perldoc.perl.org/perlre.html"
1161 >http://perldoc.perl.org/perlre.html</A
1164 > Note that the path pattern is automatically left-anchored at the <SPAN
1168 i.e. it matches as if it would start with a <SPAN
1171 > (regular expression speak
1172 for the beginning of a line).</P
1174 > Please also note that matching in the path is <SPAN
1178 >CASE INSENSITIVE</I
1181 by default, but you can switch to case sensitive at any point in the pattern by using the
1187 >www.example.com/(?-i)PaTtErN.*</TT
1189 only documents whose path starts with <TT
1199 > this capitalization.</P
1203 CLASS="VARIABLELIST"
1208 >.example.com/.*</TT
1212 > Is equivalent to just <SPAN
1214 >".example.com"</SPAN
1215 >, since any documents
1216 within that domain are matched with or without the <SPAN
1220 regular expression. This is redundant
1226 >.example.com/.*/index.html$</TT
1230 > Will match any page in the domain of <SPAN
1232 >"example.com"</SPAN
1237 >, and that is part of some path. For
1238 example, it matches <SPAN
1240 >"www.example.com/testing/index.html"</SPAN
1244 >"www.example.com/index.html"</SPAN
1245 > because the regular
1246 expression called for at least two <SPAN
1250 requirement. It also would match
1253 >"www.example.com/testing/index_html"</SPAN
1255 special meta-character <SPAN
1264 >.example.com/(.*/)?index\.html$</TT
1268 > This regular expression is conditional so it will match any page
1272 > regardless of path which in this case can
1273 have one or more <SPAN
1276 >. And this one must contain exactly
1280 > (but does not have to end with that!).
1286 >.example.com/(.*/)(ads|banners?|junk)</TT
1290 > This regular expression will match any path of <SPAN
1292 >"example.com"</SPAN
1294 that contains any of the words <SPAN
1304 > (because of the <SPAN
1311 The path does not have to end in these words, just contain them.
1317 >.example.com/(.*/)(ads|banners?|junk)/.*\.(jpe?g|gif|png)$</TT
1321 > This is very much the same as above, except now it must end in either
1335 one is limited to common image formats.
1341 > There are many, many good examples to be found in <TT
1345 and more tutorials below in <A
1346 HREF="appendix.html#REGEX"
1347 >Appendix on regular expressions</A
1356 >8.4.3. The Tag Pattern</A
1359 > Tag patterns are used to change the applying actions based on the
1360 request's tags. Tags can be created with either the
1362 HREF="actions-file.html#CLIENT-HEADER-TAGGER"
1363 >client-header-tagger</A
1366 HREF="actions-file.html#SERVER-HEADER-TAGGER"
1367 >server-header-tagger</A
1370 > Tag patterns have to start with <SPAN
1377 can tell them apart from URL patterns. Everything after the colon
1378 including white space, is interpreted as a regular expression with
1379 path pattern syntax, except that tag patterns aren't left-anchored
1380 automatically (<SPAN
1383 > doesn't silently add a <SPAN
1387 you have to do it yourself if you need it).</P
1389 > To match all requests that are tagged with <SPAN
1393 your pattern line should be <SPAN
1400 > would work as well, but it would also
1401 match requests whose tags contain <SPAN
1408 > wouldn't work as it requires white space.</P
1410 > Sections can contain URL and tag patterns at the same time,
1411 but tag patterns are checked after the URL patterns and thus
1412 always overrule them, even if they are located before the URL patterns.</P
1414 > Once a new tag is added, Privoxy checks right away if it's matched by one
1415 of the tag patterns and updates the action settings accordingly. As a result
1416 tags can be used to activate other tagger actions, as long as these other
1417 taggers look for headers that haven't already be parsed.</P
1419 > For example you could tag client requests which use the
1424 then use this tag to activate another tagger that adds a tag if cookies
1425 are sent, and then use a block action based on the cookie tag. This allows
1426 the outcome of one action, to be input into a subsequent action. However if
1427 you'd reverse the position of the described taggers, and activated the
1428 method tagger based on the cookie tagger, no method tags would be created.
1429 The method tagger would look for the request line, but at the time
1430 the cookie tag is created, the request line has already been parsed.</P
1432 > While this is a limitation you should be aware of, this kind of
1433 indirection is seldom needed anyway and even the example doesn't
1434 make too much sense.</P
1446 > All actions are disabled by default, until they are explicitly enabled
1447 somewhere in an actions file. Actions are turned on if preceded with a
1451 >, and turned off if preceded with a <SPAN
1460 >"do that action"</SPAN
1467 >"please block URLs that match the
1468 following patterns"</SPAN
1475 block URLs that match the following patterns, even if <TT
1479 previously applied."</SPAN
1483 Again, actions are invoked by placing them on a line, enclosed in curly braces and
1484 separated by whitespace, like in
1487 >{+some-action -some-other-action{some-parameter}}</TT
1489 followed by a list of URL patterns, one per line, to which they apply.
1490 Together, the actions line and the following pattern lines make up a section
1491 of the actions file. </P
1494 Actions fall into three categories:</P
1502 Boolean, i.e the action can only be <SPAN
1525 > # enable action <TT
1536 > # disable action <TT
1558 Parameterized, where some value is required in order to enable this type of action.
1580 >} # enable action and set parameter to <TT
1586 # overwriting parameter from previous match if necessary
1592 > # disable action. The parameter can be omitted</PRE
1599 > Note that if the URL matches multiple positive forms of a parameterized action,
1600 the last match wins, i.e. the params from earlier matches are simply ignored.
1606 >+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
1613 Multi-value. These look exactly like parameterized actions,
1614 but they behave differently: If the action applies multiple times to the
1615 same URL, but with different parameters, <SPAN
1628 > matches are remembered. This is used for actions
1629 that can be executed for the same request repeatedly, like adding multiple
1630 headers, or filtering through multiple filters. Syntax:
1651 >} # enable action and add <TT
1656 > to the list of parameters
1667 >} # remove the parameter <TT
1672 > from the list of parameters
1673 # If it was the last one left, disable the action.
1679 > # disable this action completely and remove all parameters from the list</PRE
1689 >+add-header{X-Fun-Header: Some text}</TT
1693 >+filter{html-annoyances}</TT
1700 > If nothing is specified in any actions file, no <SPAN
1704 taken. So in this case <SPAN
1708 normal, non-blocking, non-filtering proxy. You must specifically enable the
1709 privacy and blocking features you need (although the provided default actions
1710 files will give a good starting point).</P
1712 > Later defined action sections always over-ride earlier ones of the same type.
1713 So exceptions to any rules you make, should come in the latter part of the file (or
1714 in a file that is processed later when using multiple actions files such
1718 >). For multi-valued actions, the actions
1719 are applied in the order they are specified. Actions files are processed in
1720 the order they are defined in <TT
1724 installation has three actions files). It also quite possible for any given
1725 URL to match more than one <SPAN
1728 > (because of wildcards and
1729 regular expressions), and thus to trigger more than one set of actions! Last
1732 > The list of valid <SPAN
1742 >8.5.1. add-header</A
1747 CLASS="VARIABLELIST"
1753 >Confuse log analysis, custom applications</P
1759 > Sends a user defined HTTP header to the web server.
1772 > Any string value is possible. Validity of the defined HTTP headers is not checked.
1773 It is recommended that you use the <SPAN
1787 > This action may be specified multiple times, in order to define multiple
1788 headers. This is rarely needed for the typical user. If you don't know what
1791 >"HTTP headers"</SPAN
1792 > are, you definitely don't need to worry about this
1808 >+add-header{X-User-Tracking: sucks}</PRE
1829 CLASS="VARIABLELIST"
1835 >Block ads or other unwanted content</P
1841 > Requests for URLs to which this action applies are blocked, i.e. the
1842 requests are trapped by <SPAN
1845 > and the requested URL is never retrieved,
1846 but is answered locally with a substitute page or image, as determined by
1850 HREF="actions-file.html#HANDLE-AS-IMAGE"
1857 HREF="actions-file.html#SET-IMAGE-BLOCKER"
1858 >set-image-blocker</A
1864 HREF="actions-file.html#HANDLE-AS-EMPTY-DOCUMENT"
1865 >handle-as-empty-document</A
1890 > sends a special <SPAN
1894 for requests to blocked pages. This page contains links to find out why the request
1895 was blocked, and a click-through to the blocked content (the latter only if compiled with the
1896 force feature enabled). The <SPAN
1899 > page adapts to the available
1900 screen space -- it displays full-blown if space allows, or miniaturized and text-only
1901 if loaded into a small frame or window. If you are using <SPAN
1905 right now, you can take a look at the
1907 HREF="http://ads.bannerserver.example.com/nasty-ads/sponsor.html"
1918 A very important exception occurs if <SPAN
1931 HREF="actions-file.html#HANDLE-AS-IMAGE"
1935 apply to the same request: it will then be replaced by an image. If
1939 HREF="actions-file.html#SET-IMAGE-BLOCKER"
1940 >set-image-blocker</A
1943 (see below) also applies, the type of image will be determined by its parameter,
1944 if not, the standard checkerboard pattern is sent.
1947 > It is important to understand this process, in order
1948 to understand how <SPAN
1952 ads and other unwanted content. Blocking is a core feature, and one
1953 upon which various other features depend.
1959 HREF="actions-file.html#FILTER"
1963 action can perform a very similar task, by <SPAN
1967 banner images and other content through rewriting the relevant URLs in the
1968 document's HTML source, so they don't get requested in the first place.
1969 Note that this is a totally different technique, and it's easy to confuse the two.
1973 >Example usage (section):</DT
1985 # Block and replace with "blocked" page
1986 .nasty-stuff.example.com
1988 {+block +handle-as-image}
1989 # Block and replace with image
1993 {+block +handle-as-empty-document}
1994 # Block and then ignore
1995 adserver.exampleclick.net/.*\.js$</PRE
2010 NAME="CLIENT-HEADER-FILTER"
2011 >8.5.3. client-header-filter</A
2016 CLASS="VARIABLELIST"
2022 > Rewrite or remove single client headers.
2029 > All client headers to which this action applies are filtered on-the-fly through
2030 the specified regular expression based substitutions.
2043 > The name of a client-header filter, as defined in one of the
2045 HREF="filter-file.html"
2054 > Client-header filters are applied to each header on its own, not to
2055 all at once. This makes it easier to diagnose problems, but on the downside
2056 you can't write filters that only change header x if header y's value is z.
2057 You can do that by using tags though.
2060 > Client-header filters are executed after the other header actions have finished
2061 and use their output as input.
2064 > Please refer to the <A
2065 HREF="filter-file.html"
2066 >filter file chapter</A
2068 to learn which client-header filters are available by default, and how to
2073 >Example usage (section):</DT
2084 >{+client-header-filter{hide-tor-exit-notation}}
2101 NAME="CLIENT-HEADER-TAGGER"
2102 >8.5.4. client-header-tagger</A
2107 CLASS="VARIABLELIST"
2113 > Block requests based on their headers.
2120 > Client headers to which this action applies are filtered on-the-fly through
2121 the specified regular expression based substitutions, the result is used as
2135 > The name of a client-header tagger, as defined in one of the
2137 HREF="filter-file.html"
2146 > Client-header taggers are applied to each header on its own,
2147 and as the header isn't modified, each tagger <SPAN
2154 > Client-header taggers are the first actions that are executed
2155 and their tags can be used to control every other action.
2159 >Example usage (section):</DT
2170 ># Tag every request with the User-Agent header
2171 {+client-header-tagger{user-agent}}
2188 NAME="CONTENT-TYPE-OVERWRITE"
2189 >8.5.5. content-type-overwrite</A
2194 CLASS="VARIABLELIST"
2200 >Stop useless download menus from popping up, or change the browser's rendering mode</P
2206 > Replaces the <SPAN
2208 >"Content-Type:"</SPAN
2209 > HTTP server header.
2231 >"Content-Type:"</SPAN
2232 > HTTP server header is used by the
2233 browser to decide what to do with the document. The value of this
2234 header can cause the browser to open a download menu instead of
2235 displaying the document by itself, even if the document's format is
2236 supported by the browser.
2239 > The declared content type can also affect which rendering mode
2240 the browser chooses. If XHTML is delivered as <SPAN
2244 many browsers treat it as yet another broken HTML document.
2245 If it is send as <SPAN
2247 >"application/xml"</SPAN
2249 XHTML support will only display it, if the syntax is correct.
2252 > If you see a web site that proudly uses XHTML buttons, but sets
2255 >"Content-Type: text/html"</SPAN
2256 >, you can use <SPAN
2260 to overwrite it with <SPAN
2262 >"application/xml"</SPAN
2264 the web master's claim inside your XHTML-supporting browser.
2265 If the syntax is incorrect, the browser will complain loudly.
2268 > You can also go the opposite direction: if your browser prints
2269 error messages instead of rendering a document falsely declared
2270 as XHTML, you can overwrite the content type with
2274 > and have it rendered as broken HTML document.
2279 >content-type-overwrite</TT
2283 >"Content-Type:"</SPAN
2284 > headers that look like some kind of text.
2285 If you want to overwrite it unconditionally, you have to combine it with
2289 HREF="actions-file.html#FORCE-TEXT-MODE"
2293 This limitation exists for a reason, think twice before circumventing it.
2296 > Most of the time it's easier to replace this action with a custom
2300 HREF="actions-file.html#SERVER-HEADER-FILTER"
2301 >server-header filter</A
2304 It allows you to activate it for every document of a certain site and it will still
2305 only replace the content types you aimed at.
2308 > Of course you can apply <TT
2310 >content-type-overwrite</TT
2312 to a whole site and then make URL based exceptions, but it's a lot
2313 more work to get the same precision.
2317 >Example usage (sections):</DT
2328 ># Check if www.example.net/ really uses valid XHTML
2329 { +content-type-overwrite{application/xml} }
2332 # but leave the content type unmodified if the URL looks like a style sheet
2333 {-content-type-overwrite}
2334 www.example.net/.*\.css$
2335 www.example.net/.*style</PRE
2350 NAME="CRUNCH-CLIENT-HEADER"
2351 >8.5.6. crunch-client-header</A
2356 CLASS="VARIABLELIST"
2362 >Remove a client header <SPAN
2365 > has no dedicated action for.</P
2371 > Deletes every header sent by the client that contains the string the user supplied as parameter.
2391 > This action allows you to block client headers for which no dedicated
2399 > will remove every client header that
2400 contains the string you supplied as parameter.
2403 > Regular expressions are <SPAN
2410 use this action to block different headers in the same request, unless
2411 they contain the same string.
2416 >crunch-client-header</TT
2417 > is only meant for quick tests.
2418 If you have to block several different headers, or only want to modify
2419 parts of them, you should use a
2423 HREF="actions-file.html#CLIENT-HEADER-FILTER"
2424 >client-header filter</A
2447 > Don't block any header without understanding the consequences.
2455 >Example usage (section):</DT
2466 ># Block the non-existent "Privacy-Violation:" client header
2467 { +crunch-client-header{Privacy-Violation:} }
2484 NAME="CRUNCH-IF-NONE-MATCH"
2485 >8.5.7. crunch-if-none-match</A
2490 CLASS="VARIABLELIST"
2496 >Prevent yet another way to track the user's steps between sessions.</P
2504 >"If-None-Match:"</SPAN
2505 > HTTP client header.
2525 > Removing the <SPAN
2527 >"If-None-Match:"</SPAN
2528 > HTTP client header
2529 is useful for filter testing, where you want to force a real
2530 reload instead of getting status code <SPAN
2534 would cause the browser to use a cached copy of the page.
2537 > It is also useful to make sure the header isn't used as a cookie
2538 replacement (unlikely but possible).
2541 > Blocking the <SPAN
2543 >"If-None-Match:"</SPAN
2544 > header shouldn't cause any
2545 caching problems, as long as the <SPAN
2547 >"If-Modified-Since:"</SPAN
2549 isn't blocked or missing as well.
2552 > It is recommended to use this action together with
2556 HREF="actions-file.html#HIDE-IF-MODIFIED-SINCE"
2557 >hide-if-modified-since</A
2564 HREF="actions-file.html#OVERWRITE-LAST-MODIFIED"
2565 >overwrite-last-modified</A
2571 >Example usage (section):</DT
2582 ># Let the browser revalidate cached documents but don't
2583 # allow the server to use the revalidation headers for user tracking.
2584 {+hide-if-modified-since{-60} \
2585 +overwrite-last-modified{randomize} \
2586 +crunch-if-none-match}
2602 NAME="CRUNCH-INCOMING-COOKIES"
2603 >8.5.8. crunch-incoming-cookies</A
2608 CLASS="VARIABLELIST"
2614 > Prevent the web server from setting HTTP cookies on your system
2623 >"Set-Cookie:"</SPAN
2624 > HTTP headers from server replies.
2644 > This action is only concerned with <SPAN
2661 HREF="actions-file.html#CRUNCH-OUTGOING-COOKIES"
2662 >crunch-outgoing-cookies</A
2671 > to disable HTTP cookies completely.
2680 > to use this action in conjunction
2684 HREF="actions-file.html#SESSION-COOKIES-ONLY"
2685 >session-cookies-only</A
2688 since it would prevent the session cookies from being set. See also
2692 HREF="actions-file.html#FILTER-CONTENT-COOKIES"
2693 >filter-content-cookies</A
2710 >+crunch-incoming-cookies</PRE
2725 NAME="CRUNCH-SERVER-HEADER"
2726 >8.5.9. crunch-server-header</A
2731 CLASS="VARIABLELIST"
2737 >Remove a server header <SPAN
2740 > has no dedicated action for.</P
2746 > Deletes every header sent by the server that contains the string the user supplied as parameter.
2766 > This action allows you to block server headers for which no dedicated
2770 > action exists. <SPAN
2774 will remove every server header that contains the string you supplied as parameter.
2777 > Regular expressions are <SPAN
2784 use this action to block different headers in the same request, unless
2785 they contain the same string.
2790 >crunch-server-header</TT
2791 > is only meant for quick tests.
2792 If you have to block several different headers, or only want to modify
2793 parts of them, you should use a custom
2797 HREF="actions-file.html#SERVER-HEADER-FILTER"
2798 >server-header filter</A
2821 > Don't block any header without understanding the consequences.
2829 >Example usage (section):</DT
2840 ># Crunch server headers that try to prevent caching
2841 { +crunch-server-header{no-cache} }
2857 NAME="CRUNCH-OUTGOING-COOKIES"
2858 >8.5.10. crunch-outgoing-cookies</A
2863 CLASS="VARIABLELIST"
2869 > Prevent the web server from reading any HTTP cookies from your system
2879 > HTTP headers from client requests.
2899 > This action is only concerned with <SPAN
2916 HREF="actions-file.html#CRUNCH-INCOMING-COOKIES"
2917 >crunch-incoming-cookies</A
2926 > to disable HTTP cookies completely.
2935 > to use this action in conjunction
2939 HREF="actions-file.html#SESSION-COOKIES-ONLY"
2940 >session-cookies-only</A
2943 since it would prevent the session cookies from being read.
2958 >+crunch-outgoing-cookies</PRE
2973 NAME="DEANIMATE-GIFS"
2974 >8.5.11. deanimate-gifs</A
2979 CLASS="VARIABLELIST"
2985 >Stop those annoying, distracting animated GIF images.</P
2991 > De-animate GIF animations, i.e. reduce them to their first or last image.
3017 > This will also shrink the images considerably (in bytes, not pixels!). If
3021 > is given, the first frame of the animation
3022 is used as the replacement. If <SPAN
3025 > is given, the last
3026 frame of the animation is used instead, which probably makes more sense for
3027 most banner animations, but also has the risk of not showing the entire
3028 last frame (if it is only a delta to an earlier frame).
3031 > You can safely use this action with patterns that will also match non-GIF
3032 objects, because no attempt will be made at anything that doesn't look like
3048 >+deanimate-gifs{last}</PRE
3063 NAME="DOWNGRADE-HTTP-VERSION"
3064 >8.5.12. downgrade-http-version</A
3069 CLASS="VARIABLELIST"
3075 >Work around (very rare) problems with HTTP/1.1</P
3081 > Downgrades HTTP/1.1 client requests and server replies to HTTP/1.0.
3101 > This is a left-over from the time when <SPAN
3105 didn't support important HTTP/1.1 features well. It is left here for the
3106 unlikely case that you experience HTTP/1.1 related problems with some server
3107 out there. Not all HTTP/1.1 features and requirements are supported yet,
3108 so there is a chance you might need this action.
3112 >Example usage (section):</DT
3123 >{+downgrade-http-version}
3124 problem-host.example.com</PRE
3139 NAME="FAST-REDIRECTS"
3140 >8.5.13. fast-redirects</A
3145 CLASS="VARIABLELIST"
3151 >Fool some click-tracking scripts and speed up indirect links.</P
3157 > Detects redirection URLs and redirects the browser without contacting
3158 the redirection server first.
3177 >"simple-check"</SPAN
3178 > to just search for the string <SPAN
3182 to detect redirection URLs.
3189 >"check-decoded-url"</SPAN
3190 > to decode URLs (if necessary) before searching
3191 for redirection URLs.
3201 Many sites, like yahoo.com, don't just link to other sites. Instead, they
3202 will link to some script on their own servers, giving the destination as a
3203 parameter, which will then redirect you to the final target. URLs
3204 resulting from this scheme typically look like:
3207 >"http://www.example.org/click-tracker.cgi?target=http%3a//www.example.net/"</SPAN
3211 > Sometimes, there are even multiple consecutive redirects encoded in the
3212 URL. These redirections via scripts make your web browsing more traceable,
3213 since the server from which you follow such a link can see where you go
3214 to. Apart from that, valuable bandwidth and time is wasted, while your
3215 browser asks the server for one redirect after the other. Plus, it feeds
3219 > This feature is currently not very smart and is scheduled for improvement.
3220 If it is enabled by default, you will have to create some exceptions to
3221 this action. It can lead to failures in several ways:
3224 > Not every URLs with other URLs as parameters is evil.
3225 Some sites offer a real service that requires this information to work.
3226 For example a validation service needs to know, which document to validate.
3230 > assumes that every URL parameter that
3231 looks like another URL is a redirection target, and will always redirect to
3232 the last one. Most of the time the assumption is correct, but if it isn't,
3233 the user gets redirected anyway.
3236 > Another failure occurs if the URL contains other parameters after the URL parameter.
3240 >"http://www.example.org/?redirect=http%3a//www.example.net/&foo=bar"</SPAN
3242 contains the redirection URL <SPAN
3244 >"http://www.example.net/"</SPAN
3246 followed by another parameter. <TT
3250 and will cause a redirect to <SPAN
3252 >"http://www.example.net/&foo=bar"</SPAN
3254 Depending on the target server configuration, the parameter will be silently ignored
3257 >"page not found"</SPAN
3258 > error. You can prevent this problem by
3262 HREF="actions-file.html#REDIRECT"
3266 to remove the last part of the URL, but it requires a little effort.
3269 > To detect a redirection URL, <TT
3273 looks for the string <SPAN
3276 >, either in plain text
3277 (invalid but often used) or encoded as <SPAN
3281 Some sites use their own URL encoding scheme, encrypt the address
3282 of the target server or replace it with a database id. In theses cases
3286 > is fooled and the request reaches the
3287 redirection server where it probably gets logged.
3302 > { +fast-redirects{simple-check} }
3305 { +fast-redirects{check-decoded-url} }
3306 another.example.com/testing</PRE
3327 CLASS="VARIABLELIST"
3333 >Get rid of HTML and JavaScript annoyances, banner advertisements (by size),
3334 do fun text replacements, add personalized effects, etc.</P
3340 > All instances of text-based type, most notably HTML and JavaScript, to which
3341 this action applies, can be filtered on-the-fly through the specified regular
3342 expression based substitutions. (Note: as of version 3.0.3 plain text documents
3343 are exempted from filtering, because web servers often use the
3347 > MIME type for all files whose type they don't know.)
3360 > The name of a content filter, as defined in the <A
3361 HREF="filter-file.html"
3364 Filters can be defined in one or more files as defined by the
3368 HREF="config.html#FILTERFILE"
3379 > is the collection of filters
3380 supplied by the developers. Locally defined filters should go
3381 in their own file, such as <TT
3387 > When used in its negative form,
3388 and without parameters, <SPAN
3394 > filtering is completely disabled.
3401 > For your convenience, there are a number of pre-defined filters available
3402 in the distribution filter file that you can use. See the examples below for
3406 > Filtering requires buffering the page content, which may appear to
3407 slow down page rendering since nothing is displayed until all content has
3408 passed the filters. (It does not really take longer, but seems that way
3409 since the page is not incrementally displayed.) This effect will be more
3410 noticeable on slower connections.
3415 >"Rolling your own"</SPAN
3417 filters requires a knowledge of
3419 HREF="http://en.wikipedia.org/wiki/Regular_expressions"
3428 HREF="http://en.wikipedia.org/wiki/Html"
3435 This is very powerful feature, and potentially very intrusive.
3436 Filters should be used with caution, and where an equivalent
3443 > The amount of data that can be filtered is limited to the
3447 HREF="config.html#BUFFER-LIMIT"
3451 option in the main <A
3455 default is 4096 KB (4 Megs). Once this limit is exceeded, the buffered
3456 data, and all pending data, is passed through unfiltered.
3459 > Inappropriate MIME types, such as zipped files, are not filtered at all.
3460 (Again, only text-based types except plain text). Encrypted SSL data
3461 (from HTTPS servers) cannot be filtered either, since this would violate
3462 the integrity of the secure transaction. In some situations it might
3463 be necessary to protect certain text, like source code, from filtering
3464 by defining appropriate <TT
3470 > Compressed content can't be filtered either, unless <SPAN
3474 is compiled with zlib support (requires at least <SPAN
3481 > will decompress the content before filtering
3485 > If you use a <SPAN
3488 > version without zlib support, but want filtering to work on
3489 as much documents as possible, even those that would normally be sent compressed,
3490 you must use the <TT
3493 HREF="actions-file.html#PREVENT-COMPRESSION"
3494 >prevent-compression</A
3497 action in conjunction with <TT
3503 > Content filtering can achieve some of the same effects as the
3507 HREF="actions-file.html#BLOCK"
3511 action, i.e. it can be used to block ads and banners. But the mechanism
3512 works quite differently. One effective use, is to block ad banners
3513 based on their size (see below), since many of these seem to be somewhat
3520 > with suggestions for new or
3521 improved filters is particularly welcome!
3524 > The below list has only the names and a one-line description of each
3525 predefined filter. There are <A
3526 HREF="filter-file.html#PREDEFINED-FILTERS"
3528 verbose explanations</A
3529 > of what these filters do in the <A
3530 HREF="filter-file.html"
3531 >filter file chapter</A
3536 >Example usage (with filters from the distribution <TT
3541 HREF="filter-file.html#PREDEFINED-FILTERS"
3542 >the Predefined Filters section</A
3544 more explanation on each:</DT
3548 NAME="FILTER-JS-ANNOYANCES"
3559 >+filter{js-annoyances} # Get rid of particularly annoying JavaScript abuse</PRE
3567 NAME="FILTER-JS-EVENTS"
3578 >+filter{js-events} # Kill all JS event bindings (Radically destructive! Only for extra nasty sites)</PRE
3586 NAME="FILTER-HTML-ANNOYANCES"
3597 >+filter{html-annoyances} # Get rid of particularly annoying HTML abuse</PRE
3605 NAME="FILTER-CONTENT-COOKIES"
3616 >+filter{content-cookies} # Kill cookies that come in the HTML or JS content</PRE
3624 NAME="FILTER-REFRESH-TAGS"
3635 >+filter{refresh-tags} # Kill automatic refresh tags (for dial-on-demand setups)</PRE
3643 NAME="FILTER-UNSOLICITED-POPUPS"
3654 >+filter{unsolicited-popups} # Disable only unsolicited pop-up windows. Useful if your browser lacks this ability.</PRE
3662 NAME="FILTER-ALL-POPUPS"
3673 >+filter{all-popups} # Kill all popups in JavaScript and HTML. Useful if your browser lacks this ability.</PRE
3681 NAME="FILTER-IMG-REORDER"
3692 >+filter{img-reorder} # Reorder attributes in <img> tags to make the banners-by-* filters more effective</PRE
3700 NAME="FILTER-BANNERS-BY-SIZE"
3711 >+filter{banners-by-size} # Kill banners by size</PRE
3719 NAME="FILTER-BANNERS-BY-LINK"
3730 >+filter{banners-by-link} # Kill banners by their links to known clicktrackers</PRE
3738 NAME="FILTER-WEBBUGS"
3749 >+filter{webbugs} # Squish WebBugs (1x1 invisible GIFs used for user tracking)</PRE
3757 NAME="FILTER-TINY-TEXTFORMS"
3768 >+filter{tiny-textforms} # Extend those tiny textareas up to 40x80 and kill the hard wrap</PRE
3776 NAME="FILTER-JUMPING-WINDOWS"
3787 >+filter{jumping-windows} # Prevent windows from resizing and moving themselves</PRE
3795 NAME="FILTER-FRAMESET-BORDERS"
3806 >+filter{frameset-borders} # Give frames a border and make them resizeable</PRE
3814 NAME="FILTER-DEMORONIZER"
3825 >+filter{demoronizer} # Fix MS's non-standard use of standard charsets</PRE
3833 NAME="FILTER-SHOCKWAVE-FLASH"
3844 >+filter{shockwave-flash} # Kill embedded Shockwave Flash objects</PRE
3852 NAME="FILTER-QUICKTIME-KIOSKMODE"
3863 >+filter{quicktime-kioskmode} # Make Quicktime movies savable</PRE
3882 >+filter{fun} # Text replacements for subversive browsing fun!</PRE
3890 NAME="FILTER-CRUDE-PARENTAL"
3901 >+filter{crude-parental} # Crude parental filtering (demo only)</PRE
3909 NAME="FILTER-IE-EXPLOITS"
3920 >+filter{ie-exploits} # Disable a known Internet Explorer bug exploits</PRE
3928 NAME="FILTER-SITE-SPECIFICS"
3939 >+filter{site-specifics} # Custom filters for specific site related problems</PRE
3947 NAME="FILTER-GOOGLE"
3958 >+filter{google} # Removes text ads and other Google specific improvements</PRE
3977 >+filter{yahoo} # Removes text ads and other Yahoo specific improvements</PRE
3996 >+filter{msn} # Removes text ads and other MSN specific improvements</PRE
4004 NAME="FILTER-BLOGSPOT"
4015 >+filter{blogspot} # Cleans up Blogspot blogs</PRE
4023 NAME="FILTER-NO-PING"
4034 >+filter{no-ping} # Removes non-standard ping attributes from anchor and area tags</PRE
4049 NAME="FORCE-TEXT-MODE"
4050 >8.5.15. force-text-mode</A
4055 CLASS="VARIABLELIST"
4064 > to treat a document as if it was in some kind of <SPAN
4076 > Declares a document as text, even if the <SPAN
4078 >"Content-Type:"</SPAN
4079 > isn't detected as such.
4102 HREF="actions-file.html#FILTER"
4109 > tries to only filter files that are
4110 in some kind of text format. The same restrictions apply to
4114 HREF="actions-file.html#CONTENT-TYPE-OVERWRITE"
4115 >content-type-overwrite</A
4120 >force-text-mode</TT
4121 > declares a document as text,
4122 without looking at the <SPAN
4124 >"Content-Type:"</SPAN
4146 > Think twice before activating this action. Filtering binary data
4147 with regular expressions can cause file damage.
4182 NAME="FORWARD-OVERRIDE"
4183 >8.5.16. forward-override</A
4188 CLASS="VARIABLELIST"
4194 >Change the forwarding settings based on User-Agent or request origin</P
4200 > Overrules the forward directives in the configuration file.
4220 > to use a direct connection without any additional proxies.</P
4226 >"forward 127.0.0.1:8123"</SPAN
4227 > to use the HTTP proxy listening at 127.0.0.1 port 8123.
4234 >"forward-socks4a 127.0.0.1:9050 ."</SPAN
4235 > to use the socks4a proxy listening at
4236 127.0.0.1 port 9050. Replace <SPAN
4238 >"forward-socks4a"</SPAN
4241 >"forward-socks4"</SPAN
4243 to use a socks4 connection (with local DNS resolution) instead.
4250 >"forward-socks4a 127.0.0.1:9050 proxy.example.org:8000"</SPAN
4251 > to use the socks4a proxy
4252 listening at 127.0.0.1 port 9050 to reach the HTTP proxy listening at proxy.example.org port 8000.
4255 >"forward-socks4a"</SPAN
4258 >"forward-socks4"</SPAN
4259 > to use a socks4 connection
4260 (with local DNS resolution) instead.
4269 > This action takes parameters similar to the
4271 HREF="config.html#FORWARDING"
4273 > directives in the configuration
4274 file, but without the URL pattern. It can be used as replacement, but normally it's only
4275 used in cases where matching based on the request URL isn't sufficient.
4296 > Please read the description for the <A
4297 HREF="config.html#FORWARDING"
4300 using this action. Forwarding to the wrong people will reduce your privacy and increase the
4301 chances of man-in-the-middle attacks.
4304 > If the ports are missing or invalid, default values will be used. This might change
4305 in the future and you shouldn't rely on it. Otherwise incorrect syntax causes Privoxy
4310 HREF="http://config.privoxy.org/show-url-info"
4312 >show-url-info CGI page</A
4314 to verify that your forward settings do what you thought the do.
4333 ># Always use direct connections for requests previously tagged as
4336 >"User-Agent: fetch libfetch/2.0"</SPAN
4338 # resuming downloads continues to work.
4339 # This way you can continue to use Tor for your normal browsing,
4340 # without overloading the Tor network with your FreeBSD ports updates
4341 # or downloads of bigger files like ISOs.
4342 {+forward-override{forward .} \
4343 -hide-if-modified-since \
4344 -overwrite-last-modified \
4346 TAG:^User-Agent: fetch libfetch/2\.0$
4362 NAME="HANDLE-AS-EMPTY-DOCUMENT"
4363 >8.5.17. handle-as-empty-document</A
4368 CLASS="VARIABLELIST"
4374 >Mark URLs that should be replaced by empty documents <SPAN
4378 >if they get blocked</I
4386 > This action alone doesn't do anything noticeable. It just marks URLs.
4390 HREF="actions-file.html#BLOCK"
4400 the presence or absence of this mark decides whether an HTML <SPAN
4404 page, or an empty document will be sent to the client as a substitute for the blocked content.
4411 > document isn't literally empty, but actually contains a single space.
4431 > Some browsers complain about syntax errors if JavaScript documents
4432 are blocked with <SPAN
4436 default HTML page; this option can be used to silence them.
4437 And of course this action can also be used to eliminate the <SPAN
4441 BLOCKED message in frames.
4444 > The content type for the empty document can be specified with
4448 HREF="actions-file.html#CONTENT-TYPE-OVERWRITE"
4449 >content-type-overwrite{}</A
4452 but usually this isn't necessary.
4467 ># Block all documents on example.org that end with ".js",
4468 # but send an empty document instead of the usual HTML message.
4469 {+block +handle-as-empty-document}
4486 NAME="HANDLE-AS-IMAGE"
4487 >8.5.18. handle-as-image</A
4492 CLASS="VARIABLELIST"
4498 >Mark URLs as belonging to images (so they'll be replaced by images <SPAN
4502 >if they do get blocked</I
4504 >, rather than HTML pages)</P
4510 > This action alone doesn't do anything noticeable. It just marks URLs as images.
4514 HREF="actions-file.html#BLOCK"
4524 the presence or absence of this mark decides whether an HTML <SPAN
4528 page, or a replacement image (as determined by the <TT
4531 HREF="actions-file.html#SET-IMAGE-BLOCKER"
4532 >set-image-blocker</A
4534 > action) will be sent to the
4535 client as a substitute for the blocked content.
4555 > The below generic example section is actually part of <TT
4559 It marks all URLs with well-known image file name extensions as images and should
4563 > Users will probably only want to use the handle-as-image action in conjunction with
4567 HREF="actions-file.html#BLOCK"
4570 >, to block sources of banners, whose URLs don't
4571 reflect the file type, like in the second example section.
4574 > Note that you cannot treat HTML pages as images in most cases. For instance, (in-line) ad
4575 frames require an HTML page to be sent, or they won't display properly.
4578 >handle-as-image</TT
4579 > in this situation will not replace the
4580 ad frame with an image, but lead to error messages.
4584 >Example usage (sections):</DT
4595 ># Generic image extensions:
4598 /.*\.(gif|jpg|jpeg|png|bmp|ico)$
4600 # These don't look like images, but they're banners and should be
4601 # blocked as images:
4603 {+block +handle-as-image}
4604 some.nasty-banner-server.com/junk.cgi\?output=trash
4606 # Banner source! Who cares if they also have non-image content?
4607 ad.doubleclick.net </PRE
4622 NAME="HIDE-ACCEPT-LANGUAGE"
4623 >8.5.19. hide-accept-language</A
4628 CLASS="VARIABLELIST"
4634 >Pretend to use different language settings.</P
4640 > Deletes or replaces the <SPAN
4642 >"Accept-Language:"</SPAN
4643 > HTTP header in client requests.
4659 >, or any user defined value.
4666 > Faking the browser's language settings can be useful to make a
4667 foreign User-Agent set with
4671 HREF="actions-file.html#HIDE-USER-AGENT"
4678 > However some sites with content in different languages check the
4681 >"Accept-Language:"</SPAN
4682 > to decide which one to take by default.
4683 Sometimes it isn't possible to later switch to another language without
4686 >"Accept-Language:"</SPAN
4690 > Therefore it's a good idea to either only change the
4693 >"Accept-Language:"</SPAN
4694 > header to languages you understand,
4695 or to languages that aren't wide spread.
4698 > Before setting the <SPAN
4700 >"Accept-Language:"</SPAN
4702 to a rare language, you should consider that it helps to
4703 make your requests unique and thus easier to trace.
4704 If you don't plan to change this header frequently,
4705 you should stick to a common language.
4709 >Example usage (section):</DT
4720 ># Pretend to use Canadian language settings.
4721 {+hide-accept-language{en-ca} \
4722 +hide-user-agent{Mozilla/5.0 (X11; U; OpenBSD i386; en-CA; rv:1.8.0.4) Gecko/20060628 Firefox/1.5.0.4} \
4739 NAME="HIDE-CONTENT-DISPOSITION"
4740 >8.5.20. hide-content-disposition</A
4745 CLASS="VARIABLELIST"
4751 >Prevent download menus for content you prefer to view inside the browser.</P
4757 > Deletes or replaces the <SPAN
4759 >"Content-Disposition:"</SPAN
4760 > HTTP header set by some servers.
4776 >, or any user defined value.
4783 > Some servers set the <SPAN
4785 >"Content-Disposition:"</SPAN
4787 documents they assume you want to save locally before viewing them.
4790 >"Content-Disposition:"</SPAN
4791 > header contains the file name
4792 the browser is supposed to use by default.
4795 > In most browsers that understand this header, it makes it impossible to
4802 > the document, without downloading it first,
4803 even if it's just a simple text file or an image.
4806 > Removing the <SPAN
4808 >"Content-Disposition:"</SPAN
4810 to prevent this annoyance, but some browsers additionally check the
4813 >"Content-Type:"</SPAN
4814 > header, before they decide if they can
4815 display a document without saving it first. In these cases, you have
4816 to change this header as well, before the browser stops displaying
4820 > It is also possible to change the server's file name suggestion
4821 to another one, but in most cases it isn't worth the time to set
4825 > This action will probably be removed in the future,
4826 use server-header filters instead.
4841 ># Disarm the download link in Sourceforge's patch tracker
4843 +content-type-overwrite{text/plain}\
4844 +hide-content-disposition{block} }
4845 .sourceforge.net/tracker/download\.php</PRE
4860 NAME="HIDE-IF-MODIFIED-SINCE"
4861 >8.5.21. hide-if-modified-since</A
4866 CLASS="VARIABLELIST"
4872 >Prevent yet another way to track the user's steps between sessions.</P
4880 >"If-Modified-Since:"</SPAN
4881 > HTTP client header or modifies its value.
4897 >, or a user defined value that specifies a range of hours.
4904 > Removing this header is useful for filter testing, where you want to force a real
4905 reload instead of getting status code <SPAN
4908 >, which would cause the
4909 browser to use a cached copy of the page.
4912 > Instead of removing the header, <TT
4914 >hide-if-modified-since</TT
4916 also add or subtract a random amount of time to/from the header's value.
4917 You specify a range of minutes where the random factor should be chosen from and
4921 > does the rest. A negative value means
4922 subtracting, a positive value adding.
4925 > Randomizing the value of the <SPAN
4927 >"If-Modified-Since:"</SPAN
4929 sure it isn't used as a cookie replacement, but you will run into
4930 caching problems if the random range is too high.
4933 > It is a good idea to only use a small negative value and let
4937 HREF="actions-file.html#OVERWRITE-LAST-MODIFIED"
4938 >overwrite-last-modified</A
4941 handle the greater changes.
4944 > It is also recommended to use this action together with
4948 HREF="actions-file.html#CRUNCH-IF-NONE-MATCH"
4949 >crunch-if-none-match</A
4955 >Example usage (section):</DT
4966 ># Let the browser revalidate without being tracked across sessions
4967 { +hide-if-modified-since{-60} \
4968 +overwrite-last-modified{randomize} \
4969 +crunch-if-none-match}
4985 NAME="HIDE-FORWARDED-FOR-HEADERS"
4986 >8.5.22. hide-forwarded-for-headers</A
4991 CLASS="VARIABLELIST"
4997 >Improve privacy by not embedding the source of the request in the HTTP headers.</P
5003 > Deletes any existing <SPAN
5005 >"X-Forwarded-for:"</SPAN
5006 > HTTP header from client requests,
5007 and prevents adding a new one.
5027 > It is safe to leave this on.
5042 >+hide-forwarded-for-headers</PRE
5057 NAME="HIDE-FROM-HEADER"
5058 >8.5.23. hide-from-header</A
5063 CLASS="VARIABLELIST"
5069 >Keep your (old and ill) browser from telling web servers your email address</P
5075 > Deletes any existing <SPAN
5078 > HTTP header, or replaces it with the
5095 >, or any user defined value.
5105 > will completely remove the header
5106 (not to be confused with the <TT
5109 HREF="actions-file.html#BLOCK"
5116 > Alternately, you can specify any value you prefer to be sent to the web
5117 server. If you do, it is a matter of fairness not to use any address that
5118 is actually used by a real person.
5121 > This action is rarely needed, as modern web browsers don't send
5140 >+hide-from-header{block}</PRE
5153 >+hide-from-header{spam-me-senseless@sittingduck.example.com}</PRE
5168 NAME="HIDE-REFERRER"
5169 >8.5.24. hide-referrer</A
5177 CLASS="VARIABLELIST"
5183 >Conceal which link you followed to get to a particular site</P
5192 > (sic) HTTP header from the client request,
5193 or replaces it with a forged one.
5212 >"conditional-block"</SPAN
5213 > to delete the header completely if the host has changed.</P
5220 > to delete the header unconditionally.</P
5227 > to pretend to be coming from the homepage of the server we are talking to.</P
5231 >Any other string to set a user defined referrer.</P
5241 >conditional-block</TT
5242 > is the only parameter,
5243 that isn't easily detected in the server's log file. If it blocks the
5244 referrer, the request will look like the visitor used a bookmark or
5245 typed in the address directly.
5248 > Leaving the referrer unmodified for requests on the same host
5249 allows the server owner to see the visitor's <SPAN
5253 but in most cases she could also get that information by comparing
5254 other parts of the log file: for example the User-Agent if it isn't
5255 a very common one, or the user's IP address if it doesn't change between
5259 > Always blocking the referrer, or using a custom one, can lead to
5260 failures on servers that check the referrer before they answer any
5261 requests, in an attempt to prevent their valuable content from being
5262 embedded or linked to elsewhere.
5267 >conditional-block</TT
5272 will work with referrer checks, as long as content and valid referring page
5273 are on the same host. Most of the time that's the case.
5280 > is an alternate spelling of
5284 > and the two can be can be freely
5285 substituted with each other. (<SPAN
5289 correct English spelling, however the HTTP specification has a bug - it
5290 requires it to be spelled as <SPAN
5308 >+hide-referrer{forge}</PRE
5321 >+hide-referrer{http://www.yahoo.com/}</PRE
5336 NAME="HIDE-USER-AGENT"
5337 >8.5.25. hide-user-agent</A
5342 CLASS="VARIABLELIST"
5348 >Conceal your type of browser and client operating system</P
5354 > Replaces the value of the <SPAN
5356 >"User-Agent:"</SPAN
5358 in client requests with the specified value.
5371 > Any user-defined string.
5396 > This can lead to problems on web sites that depend on looking at this header in
5397 order to customize their content for different browsers (which, by the
5404 > the right thing to do: good web sites
5405 work browser-independently).
5413 > Using this action in multi-user setups or wherever different types of
5414 browsers will access the same <SPAN
5424 >. In single-user, single-browser
5425 setups, you might use it to delete your OS version information from
5426 the headers, because it is an invitation to exploit known bugs for your
5427 OS. It is also occasionally useful to forge this in order to access
5428 sites that won't let you in otherwise (though there may be a good
5429 reason in some cases). Example of this: some MSN sites will not
5433 > enter, yet forging to a
5437 > user-agent works just fine.
5438 (Must be just a silly MS goof, I'm sure :-).
5441 > More information on known user-agent strings can be found at
5443 HREF="http://www.user-agents.org/"
5445 >http://www.user-agents.org/</A
5449 HREF="http://en.wikipedia.org/wiki/User_agent"
5451 >http://en.wikipedia.org/wiki/User_agent</A
5467 >+hide-user-agent{Netscape 6.1 (X11; I; Linux 2.4.18 i686)}</PRE
5482 NAME="INSPECT-JPEGS"
5483 >8.5.26. inspect-jpegs</A
5488 CLASS="VARIABLELIST"
5494 >To protect against the MS buffer over-run in JPEG processing</P
5500 > Protect against a known exploit
5520 > See Microsoft Security Bulletin MS04-028. JPEG images are one of the most
5521 common image types found across the Internet. The exploit as described can
5522 allow execution of code on the target system, giving an attacker access
5523 to the system in question by merely planting an altered JPEG image, which
5524 would have no obvious indications of what lurks inside. This action
5525 prevents this exploit.
5528 > Note that the described exploit is only one of many,
5529 using this action does not mean that you no longer
5530 have to patch the client.
5545 >+inspect-jpegs</PRE
5560 >8.5.27. kill-popups<A
5568 CLASS="VARIABLELIST"
5574 >Eliminate those annoying pop-up windows (deprecated)</P
5580 > While loading the document, replace JavaScript code that opens
5581 pop-up windows with (syntactically neutral) dummy code on the fly.
5601 > This action is basically a built-in, hardwired special-purpose filter
5602 action, but there are important differences: For <TT
5606 the document need not be buffered, so it can be incrementally rendered while
5607 downloading. But <TT
5610 > doesn't catch as many pop-ups as
5614 HREF="actions-file.html#FILTER-ALL-POPUPS"
5623 does and is not as smart as <TT
5626 HREF="actions-file.html#FILTER-UNSOLICITED-POPUPS"
5630 >unsolicited-popups</I
5638 > Think of it as a fast and efficient replacement for a filter that you
5639 can use if you don't want any filtering at all. Note that it doesn't make
5640 sense to combine it with any <TT
5643 HREF="actions-file.html#FILTER"
5647 since as soon as one <TT
5650 HREF="actions-file.html#FILTER"
5654 the whole document needs to be buffered anyway, which destroys the advantage of
5658 > action over its filter equivalent.
5661 > Killing all pop-ups unconditionally is problematic. Many shops and banks rely on
5662 pop-ups to display forms, shopping carts etc, and the <TT
5665 HREF="actions-file.html#FILTER-UNSOLICITED-POPUPS"
5669 >unsolicited-popups</I
5674 > does a better job of catching only the unwanted ones.
5677 > If the only kind of pop-ups that you want to kill are exit consoles (those
5684 > windows that appear when you close an other
5685 one), you might want to use
5689 HREF="actions-file.html#FILTER"
5701 > This action is most appropriate for browsers that don't have any controls
5702 for unwanted pop-ups. Not recommended for general usage.
5731 NAME="LIMIT-CONNECT"
5732 >8.5.28. limit-connect</A
5737 CLASS="VARIABLELIST"
5743 >Prevent abuse of <SPAN
5746 > as a TCP proxy relay or disable SSL for untrusted sites</P
5752 > Specifies to which ports HTTP CONNECT requests are allowable.
5765 > A comma-separated list of ports or port ranges (the latter using dashes, with the minimum
5766 defaulting to 0 and the maximum to 65K).
5773 > By default, i.e. if no <TT
5780 > only allows HTTP CONNECT
5781 requests to port 443 (the standard, secure HTTPS port). Use
5785 > if more fine-grained control is desired
5786 for some or all destinations.
5789 > The CONNECT methods exists in HTTP to allow access to secure websites
5793 > URLs) through proxies. It works very simply:
5794 the proxy connects to the server on the specified port, and then
5795 short-circuits its connections to the client and to the remote server.
5796 This can be a big security hole, since CONNECT-enabled proxies can be
5797 abused as TCP relays very easily.
5803 > relays HTTPS traffic without seeing
5804 the decoded content. Websites can leverage this limitation to circumvent <SPAN
5808 filters. By specifying an invalid port range you can disable HTTPS entirely.
5809 If you plan to disable SSL by default, consider enabling
5813 HREF="actions-file.html#TREAT-FORBIDDEN-CONNECTS-LIKE-BLOCKS"
5814 >treat-forbidden-connects-like-blocks</A
5817 as well, to be able to quickly create exceptions.
5821 >Example usages:</DT
5832 >+limit-connect{443} # This is the default and need not be specified.
5833 +limit-connect{80,443} # Ports 80 and 443 are OK.
5834 +limit-connect{-3, 7, 20-100, 500-} # Ports less than 3, 7, 20 to 100 and above 500 are OK.
5835 +limit-connect{-} # All ports are OK
5836 +limit-connect{,} # No HTTPS/SSL traffic is allowed</PRE
5851 NAME="PREVENT-COMPRESSION"
5852 >8.5.29. prevent-compression</A
5857 CLASS="VARIABLELIST"
5863 > Ensure that servers send the content uncompressed, so it can be
5867 HREF="actions-file.html#FILTER"
5877 > Removes the Accept-Encoding header which can be used to ask for compressed transfer.
5897 > More and more websites send their content compressed by default, which
5898 is generally a good idea and saves bandwidth. But the <TT
5901 HREF="actions-file.html#FILTER"
5907 HREF="actions-file.html#DEANIMATE-GIFS"
5914 HREF="actions-file.html#KILL-POPUPS"
5918 access to the uncompressed data.
5921 > When compiled with zlib support (available since <SPAN
5924 > 3.0.7), content that should be
5925 filtered is decompressed on-the-fly and you don't have to worry about this action.
5926 If you are using an older <SPAN
5929 > version, or one that hasn't been compiled with zlib
5930 support, this action can be used to convince the server to send the content uncompressed.
5933 > Most text-based instances compress very well, the size is seldom decreased by less than 50%,
5934 for markup-heavy instances like news feeds saving more than 90% of the original size isn't
5938 > Not using compression will therefore slow down the transfer, and you should only
5939 enable this action if you really need it. As of <SPAN
5942 > 3.0.7 it's disabled in all
5943 predefined action settings.
5946 > Note that some (rare) ill-configured sites don't handle requests for uncompressed
5947 documents correctly. Broken PHP applications tend to send an empty document body,
5948 some IIS versions only send the beginning of the content. If you enable
5951 >prevent-compression</TT
5952 > per default, you might want to add
5953 exceptions for those sites. See the example for how to do that.
5957 >Example usage (sections):</DT
5968 ># Selectively turn off compression, and enable a filter
5970 { +filter{tiny-textforms} +prevent-compression }
5971 # Match only these sites
5976 # Or instead, we could set a universal default:
5978 { +prevent-compression }
5981 # Then maybe make exceptions for broken sites:
5983 { -prevent-compression }
5999 NAME="OVERWRITE-LAST-MODIFIED"
6000 >8.5.30. overwrite-last-modified</A
6005 CLASS="VARIABLELIST"
6011 >Prevent yet another way to track the user's steps between sessions.</P
6019 >"Last-Modified:"</SPAN
6020 > HTTP server header or modifies its value.
6033 > One of the keywords: <SPAN
6038 >"reset-to-request-time"</SPAN
6050 > Removing the <SPAN
6052 >"Last-Modified:"</SPAN
6053 > header is useful for filter
6054 testing, where you want to force a real reload instead of getting status
6058 >, which would cause the browser to reuse the old
6059 version of the page.
6065 > option overwrites the value of the
6068 >"Last-Modified:"</SPAN
6069 > header with a randomly chosen time
6070 between the original value and the current time. In theory the server
6071 could send each document with a different <SPAN
6073 >"Last-Modified:"</SPAN
6075 header to track visits without using cookies. <SPAN
6079 makes it impossible and the browser can still revalidate cached documents.
6084 >"reset-to-request-time"</SPAN
6085 > overwrites the value of the
6088 >"Last-Modified:"</SPAN
6089 > header with the current time. You could use
6090 this option together with
6094 HREF="actions-file.html#HIDE-IF-MODIFIED-SINCE"
6095 >hided-if-modified-since</A
6098 to further customize your random range.
6101 > The preferred parameter here is <SPAN
6105 to use, as long as the time settings are more or less correct.
6106 If the server sets the <SPAN
6108 >"Last-Modified:"</SPAN
6109 > header to the time
6110 of the request, the random range becomes zero and the value stays the same.
6111 Therefore you should later randomize it a second time with
6115 HREF="actions-file.html#HIDE-IF-MODIFIED-SINCE"
6116 >hided-if-modified-since</A
6122 > It is also recommended to use this action together with
6126 HREF="actions-file.html#CRUNCH-IF-NONE-MATCH"
6127 >crunch-if-none-match</A
6144 ># Let the browser revalidate without being tracked across sessions
6145 { +hide-if-modified-since{-60} \
6146 +overwrite-last-modified{randomize} \
6147 +crunch-if-none-match}
6164 >8.5.31. redirect</A
6169 CLASS="VARIABLELIST"
6175 > Redirect requests to other sites.
6182 > Convinces the browser that the requested document has been moved
6183 to another location and the browser should get it from there.
6196 > An absolute URL or a single pcrs command.
6203 > Requests to which this action applies are answered with a
6204 HTTP redirect to URLs of your choosing. The new URL is
6205 either provided as parameter, or derived by applying a
6206 single pcrs command to the original URL.
6209 > This action will be ignored if you use it together with
6213 HREF="actions-file.html#BLOCK"
6217 It can be combined with
6221 HREF="actions-file.html#FAST-REDIRECTS"
6222 >fast-redirects{check-decoded-url}</A
6225 to redirect to a decoded version of a rewritten URL.
6228 > Use this action carefully, make sure not to create redirection loops
6229 and be aware that using your own redirects might make it
6230 possible to fingerprint your requests.
6234 >Example usages:</DT
6245 ># Replace example.com's style sheet with another one
6246 { +redirect{http://localhost/css-replacements/example.com.css} }
6247 example.com/stylesheet\.css
6249 # Create a short, easy to remember nickname for a favorite site
6250 # (relies on the browser accept and forward invalid URLs to <SPAN
6254 { +redirect{http://www.privoxy.org/user-manual/actions-file.html} }
6257 # Always use the expanded view for Undeadly.org articles
6258 # (Note the $ at the end of the URL pattern to make sure
6259 # the request for the rewritten URL isn't redirected as well)
6260 {+redirect{s@$@&mode=expanded@}}
6261 undeadly.org/cgi\?action=article&sid=\d*$</PRE
6276 NAME="SEND-VANILLA-WAFER"
6277 >8.5.32. send-vanilla-wafer</A
6282 CLASS="VARIABLELIST"
6288 > Feed log analysis scripts with useless data.
6295 > Sends a cookie with each request stating that you do not accept any copyright
6296 on cookies sent to you, and asking the site operator not to track you.
6316 > The vanilla wafer is a (relatively) unique header and could conceivably be used to track you.
6319 > This action is rarely used and not enabled in the default configuration.
6334 >+send-vanilla-wafer</PRE
6350 >8.5.33. send-wafer</A
6355 CLASS="VARIABLELIST"
6361 > Send custom cookies or feed log analysis scripts with even more useless data.
6368 > Sends a custom, user-defined cookie with each request.
6381 > A string of the form <SPAN
6401 > Being multi-valued, multiple instances of this action can apply to the same request,
6402 resulting in multiple cookies being sent.
6405 > This action is rarely used and not enabled in the default configuration.
6409 >Example usage (section):</DT
6420 >{+send-wafer{UsingPrivoxy=true}}
6421 my-internal-testing-server.void</PRE
6436 NAME="SERVER-HEADER-FILTER"
6437 >8.5.34. server-header-filter</A
6442 CLASS="VARIABLELIST"
6448 > Rewrite or remove single server headers.
6455 > All server headers to which this action applies are filtered on-the-fly
6456 through the specified regular expression based substitutions.
6469 > The name of a server-header filter, as defined in one of the
6471 HREF="filter-file.html"
6480 > Server-header filters are applied to each header on its own, not to
6481 all at once. This makes it easier to diagnose problems, but on the downside
6482 you can't write filters that only change header x if header y's value is z.
6483 You can do that by using tags though.
6486 > Server-header filters are executed after the other header actions have finished
6487 and use their output as input.
6490 > Please refer to the <A
6491 HREF="filter-file.html"
6492 >filter file chapter</A
6494 to learn which server-header filters are available by default, and how to
6499 >Example usage (section):</DT
6510 >{+server-header-filter{html-to-xml}}
6511 example.org/xml-instance-that-is-delivered-as-html
6513 {+server-header-filter{xml-to-html}}
6514 example.org/instance-that-is-delivered-as-xml-but-is-not
6530 NAME="SERVER-HEADER-TAGGER"
6531 >8.5.35. server-header-tagger</A
6536 CLASS="VARIABLELIST"
6542 > Enable or disable filters based on the Content-Type header.
6549 > Server headers to which this action applies are filtered on-the-fly through
6550 the specified regular expression based substitutions, the result is used as
6564 > The name of a server-header tagger, as defined in one of the
6566 HREF="filter-file.html"
6575 > Server-header taggers are applied to each header on its own,
6576 and as the header isn't modified, each tagger <SPAN
6583 > Server-header taggers are executed before all other header actions
6584 that modify server headers. Their tags can be used to control
6585 all of the other server-header actions, the content filters
6586 and the crunch actions (<A
6587 HREF="actions-file.html#REDIRECT"
6591 HREF="actions-file.html#BLOCK"
6596 > Obviously crunching based on tags created by server-header taggers
6597 doesn't prevent the request from showing up in the server's log file.
6601 >Example usage (section):</DT
6612 ># Tag every request with the content type declared by the server
6613 {+server-header-tagger{content-type}}
6630 NAME="SESSION-COOKIES-ONLY"
6631 >8.5.36. session-cookies-only</A
6636 CLASS="VARIABLELIST"
6642 > Allow only temporary <SPAN
6645 > cookies (for the current
6646 browser session <SPAN
6664 >"Set-Cookie:"</SPAN
6666 server headers. Most browsers will not store such cookies permanently and
6667 forget them in between sessions.
6687 > This is less strict than <TT
6690 HREF="actions-file.html#CRUNCH-INCOMING-COOKIES"
6691 >crunch-incoming-cookies</A
6697 HREF="actions-file.html#CRUNCH-OUTGOING-COOKIES"
6698 >crunch-outgoing-cookies</A
6700 > and allows you to browse
6701 websites that insist or rely on setting cookies, without compromising your privacy too badly.
6704 > Most browsers will not permanently store cookies that have been processed by
6707 >session-cookies-only</TT
6708 > and will forget about them between sessions.
6709 This makes profiling cookies useless, but won't break sites which require cookies so
6710 that you can log in for transactions. This is generally turned on for all
6711 sites, and is the recommended setting.
6722 >session-cookies-only</TT
6727 HREF="actions-file.html#CRUNCH-INCOMING-COOKIES"
6728 >crunch-incoming-cookies</A
6734 HREF="actions-file.html#CRUNCH-OUTGOING-COOKIES"
6735 >crunch-outgoing-cookies</A
6737 >. If you do, cookies
6738 will be plainly killed.
6741 > Note that it is up to the browser how it handles such cookies without an <SPAN
6745 field. If you use an exotic browser, you might want to try it out to be sure.
6748 > This setting also has no effect on cookies that may have been stored
6749 previously by the browser before starting <SPAN
6753 These would have to be removed manually.
6761 HREF="actions-file.html#FILTER-CONTENT-COOKIES"
6762 >content-cookies filter</A
6764 to block some types of cookies. Content cookies are not effected by
6767 >session-cookies-only</TT
6783 >+session-cookies-only</PRE
6798 NAME="SET-IMAGE-BLOCKER"
6799 >8.5.37. set-image-blocker</A
6804 CLASS="VARIABLELIST"
6810 >Choose the replacement for blocked images</P
6816 > This action alone doesn't do anything noticeable. If <SPAN
6826 HREF="actions-file.html#BLOCK"
6838 HREF="actions-file.html#HANDLE-AS-IMAGE"
6848 apply, i.e. if the request is to be blocked as an image,
6855 > the parameter of this action decides what will be
6856 sent as a replacement.
6876 > to send a built-in checkerboard pattern image. The image is visually
6877 decent, scales very well, and makes it obvious where banners were busted.
6885 > to send a built-in transparent image. This makes banners disappear
6886 completely, but makes it hard to detect where <SPAN
6890 images on a given page and complicates troubleshooting if <SPAN
6894 has blocked innocent images, like navigation icons.
6908 send a redirect to <TT
6914 to any image anywhere, even in your local filesystem via <SPAN
6918 (But note that not all browsers support redirecting to a local file system).
6921 > A good application of redirects is to use special <SPAN
6925 URLs, which send the built-in images, as <TT
6931 This has the same visual effect as specifying <SPAN
6938 the first place, but enables your browser to cache the replacement image, instead of requesting
6939 it over and over again.
6948 > The URLs for the built-in images are <SPAN
6950 >"http://config.privoxy.org/send-banner?type=<TT
6971 > There is a third (advanced) type, called <SPAN
6983 >set-image-blocker</TT
6984 >, but meant for use from <A
6985 HREF="filter-file.html"
6988 Auto will select the type of image that would have applied to the referring page, had it been an image.
7006 >+set-image-blocker{pattern}</PRE
7013 > Redirect to the BSD daemon:
7024 >+set-image-blocker{http://www.freebsd.org/gifs/dae_up3.gif}</PRE
7031 > Redirect to the built-in pattern for better caching:
7042 >+set-image-blocker{http://config.privoxy.org/send-banner?type=pattern}</PRE
7057 NAME="TREAT-FORBIDDEN-CONNECTS-LIKE-BLOCKS"
7058 >8.5.38. treat-forbidden-connects-like-blocks</A
7063 CLASS="VARIABLELIST"
7069 >Block forbidden connects with an easy to find error message.</P
7075 > If this action is enabled, <SPAN
7079 makes a difference between forbidden connects and ordinary blocks.
7103 HREF="actions-file.html#LIMIT-CONNECT"
7109 with a short error message inside the headers. If the browser doesn't display
7110 headers (most don't), you just see an empty page.
7113 > With this action enabled, <SPAN
7117 the message that is used for ordinary blocks instead. If you decide
7118 to make an exception for the page in question, you can do so by
7128 > requests the clients tell
7132 > which host they are interested
7133 in, but not which document they plan to get later. As a result, the
7136 >"Go there anyway"</SPAN
7137 > wouldn't work and is therefore suppressed.
7152 >+treat-forbidden-connects-like-blocks</PRE
7171 > Note that many of these actions have the potential to cause a page to
7172 misbehave, possibly even not to display at all. There are many ways
7173 a site designer may choose to design his site, and what HTTP header
7174 content, and other criteria, he may depend on. There is no way to have hard
7175 and fast rules for all sites. See the <A
7176 HREF="appendix.html#ACTIONSANAT"
7178 > for a brief example on troubleshooting
7201 >, can be defined by combining other actions.
7202 These can in turn be invoked just like the built-in actions.
7203 Currently, an alias name can contain any character except space, tab,
7221 > that you only use <SPAN
7241 Alias names are not case sensitive, and are not required to start with a
7248 > sign, since they are merely textually
7251 > Aliases can be used throughout the actions file, but they <SPAN
7256 defined in a special section at the top of the file!</I
7259 And there can only be one such section per actions file. Each actions file may
7260 have its own alias section, and the aliases defined in it are only visible
7261 within that file.</P
7263 > There are two main reasons to use aliases: One is to save typing for frequently
7264 used combinations of actions, the other one is a gain in flexibility: If you
7265 decide once how you want to handle shops by defining an alias called
7269 >, you can later change your policy on shops in
7276 > place, and your changes will take effect everywhere
7277 in the actions file where the <SPAN
7280 > alias is used. Calling aliases
7281 by their purpose also makes your actions files more readable.</P
7283 > Currently, there is one big drawback to using aliases, though:
7287 >'s built-in web-based action file
7288 editor honors aliases when reading the actions files, but it expands
7289 them before writing. So the effects of your aliases are of course preserved,
7290 but the aliases themselves are lost when you edit sections that use aliases
7293 > Now let's define some aliases...</P
7303 > # Useful custom aliases we can use later.
7305 # Note the (required!) section header line and that this section
7306 # must be at the top of the actions file!
7310 # These aliases just save typing later:
7311 # (Note that some already use other aliases!)
7313 +crunch-all-cookies = +<A
7314 HREF="actions-file.html#CRUNCH-INCOMING-COOKIES"
7315 >crunch-incoming-cookies</A
7317 HREF="actions-file.html#CRUNCH-OUTGOING-COOKIES"
7318 >crunch-outgoing-cookies</A
7320 -crunch-all-cookies = -<A
7321 HREF="actions-file.html#CRUNCH-INCOMING-COOKIES"
7322 >crunch-incoming-cookies</A
7324 HREF="actions-file.html#CRUNCH-OUTGOING-COOKIES"
7325 >crunch-outgoing-cookies</A
7327 +block-as-image = +block +handle-as-image
7328 allow-all-cookies = -crunch-all-cookies -<A
7329 HREF="actions-file.html#SESSION-COOKIES-ONLY"
7330 >session-cookies-only</A
7332 HREF="actions-file.html#FILTER-CONTENT-COOKIES"
7333 >filter{content-cookies}</A
7336 # These aliases define combinations of actions
7337 # that are useful for certain types of sites:
7340 HREF="actions-file.html#BLOCK"
7343 HREF="actions-file.html#FILTER"
7345 > -crunch-all-cookies -<A
7346 HREF="actions-file.html#FAST-REDIRECTS"
7349 HREF="actions-file.html#HIDE-REFERER"
7352 HREF="actions-file.html#KILL-POPUPS"
7355 HREF="actions-file.html#PREVENT-COMPRESSION"
7356 >prevent-compression</A
7359 shop = -crunch-all-cookies -<A
7360 HREF="actions-file.html#FILTER-ALL-POPUPS"
7361 >filter{all-popups}</A
7363 HREF="actions-file.html#KILL-POPUPS"
7367 # Short names for other aliases, for really lazy people ;-)
7369 c0 = +crunch-all-cookies
7370 c1 = -crunch-all-cookies</PRE
7376 > ...and put them to use. These sections would appear in the lower part of an
7377 actions file and define exceptions to the default actions (as specified further
7391 > # These sites are either very complex or very keen on
7392 # user data and require minimal interference to work:
7395 .office.microsoft.com
7396 .windowsupdate.microsoft.com
7397 # Gmail is really mail.google.com, not gmail.com
7401 # Allow cookies (for setting and retrieving your customer data)
7405 .worldpay.com # for quietpc.com
7408 # These shops require pop-ups:
7410 {-kill-popups -filter{all-popups} -filter{unsolicited-popups}}
7412 .overclockers.co.uk</PRE
7418 > Aliases like <SPAN
7424 > are typically used for
7428 > sites that require more than one action to be disabled
7429 in order to function properly.</P
7437 >8.7. Actions Files Tutorial</A
7440 > The above chapters have shown <A
7441 HREF="actions-file.html"
7442 >which actions files
7443 there are and how they are organized</A
7444 >, how actions are <A
7445 HREF="actions-file.html#ACTIONS"
7448 HREF="actions-file.html#ACTIONS-APPLY"
7452 HREF="actions-file.html#AF-PATTERNS"
7456 HREF="actions-file.html#ALIASES"
7458 >. Now, let's look at an
7466 file and see how all these pieces come together:</P
7473 >8.7.1. default.action</A
7476 >Every config file should start with a short comment stating its purpose:</P
7486 ># Sample default.action file <ijbswa-developers@lists.sourceforge.net></PRE
7492 >Then, since this is the <TT
7496 first section is a special section for internal use that you needn't
7497 change or worry about:</P
7507 >##########################################################################
7508 # Settings -- Don't change! For internal Privoxy use ONLY.
7509 ##########################################################################
7512 for-privoxy-version=3.0</PRE
7518 >After that comes the (optional) alias section. We'll use the example
7519 section from the above <A
7520 HREF="actions-file.html#ALIASES"
7521 >chapter on aliases</A
7523 that also explains why and how aliases are used:</P
7533 >##########################################################################
7535 ##########################################################################
7538 # These aliases just save typing later:
7539 # (Note that some already use other aliases!)
7541 +crunch-all-cookies = +<A
7542 HREF="actions-file.html#CRUNCH-INCOMING-COOKIES"
7543 >crunch-incoming-cookies</A
7545 HREF="actions-file.html#CRUNCH-OUTGOING-COOKIES"
7546 >crunch-outgoing-cookies</A
7548 -crunch-all-cookies = -<A
7549 HREF="actions-file.html#CRUNCH-INCOMING-COOKIES"
7550 >crunch-incoming-cookies</A
7552 HREF="actions-file.html#CRUNCH-OUTGOING-COOKIES"
7553 >crunch-outgoing-cookies</A
7555 +block-as-image = +block +handle-as-image
7556 mercy-for-cookies = -crunch-all-cookies -<A
7557 HREF="actions-file.html#SESSION-COOKIES-ONLY"
7558 >session-cookies-only</A
7560 HREF="actions-file.html#FILTER-CONTENT-COOKIES"
7561 >filter{content-cookies}</A
7564 # These aliases define combinations of actions
7565 # that are useful for certain types of sites:
7568 HREF="actions-file.html#BLOCK"
7571 HREF="actions-file.html#FILTER"
7573 > -crunch-all-cookies -<A
7574 HREF="actions-file.html#FAST-REDIRECTS"
7577 HREF="actions-file.html#HIDE-REFERER"
7580 HREF="actions-file.html#KILL-POPUPS"
7583 shop = -crunch-all-cookies -<A
7584 HREF="actions-file.html#FILTER-ALL-POPUPS"
7585 >filter{all-popups}</A
7587 HREF="actions-file.html#KILL-POPUPS"
7595 > Now come the regular sections, i.e. sets of actions, accompanied
7596 by URL patterns to which they apply. Remember <SPAN
7601 are disabled when matching starts</I
7603 >, so we have to explicitly
7604 enable the ones we want.</P
7606 > The first regular section is probably the most important. It has only
7615 HREF="actions-file.html#AF-PATTERNS"
7616 >matches all URLs</A
7618 set of actions used in this <SPAN
7626 be applied to all requests as a start</I
7628 >. It can be partly or
7629 wholly overridden by later matches further down this file, or in user.action,
7630 but it will still be largely responsible for your overall browsing
7633 > Again, at the start of matching, all actions are disabled, so there is
7634 no need to disable any actions here. (Remember: a <SPAN
7638 preceding the action name enables the action, a <SPAN
7642 Also note how this long line has been made more readable by splitting it into
7643 multiple lines with line continuation.</P
7653 >##########################################################################
7654 # "Defaults" section:
7655 ##########################################################################
7658 HREF="actions-file.html#DEANIMATE-GIFS"
7662 HREF="actions-file.html#FILTER-HTML-ANNOYANCES"
7663 >filter{html-annoyances}</A
7666 HREF="actions-file.html#FILTER-REFRESH-TAGS"
7667 >filter{refresh-tags}</A
7670 HREF="actions-file.html#FILTER-WEBBUGS"
7674 HREF="actions-file.html#FILTER-IE-EXPLOITS"
7675 >filter{ie-exploits}</A
7678 HREF="actions-file.html#HIDE-FORWARDED-FOR-HEADERS"
7679 >hide-forwarded-for-headers</A
7682 HREF="actions-file.html#HIDE-FROM-HEADER"
7683 >hide-from-header{block}</A
7686 HREF="actions-file.html#HIDE-REFERER"
7687 >hide-referrer{forge}</A
7690 HREF="actions-file.html#PREVENT-COMPRESSION"
7691 >prevent-compression</A
7694 HREF="actions-file.html#SESSION-COOKIES-ONLY"
7695 >session-cookies-only</A
7698 HREF="actions-file.html#SET-IMAGE-BLOCKER"
7699 >set-image-blocker{pattern}</A
7702 / # forward slash will match *all* potential URL patterns.</PRE
7708 > The default behavior is now set.
7711 > The first of our specialized sections is concerned with <SPAN
7715 sites, i.e. sites that require minimum interference, because they are either
7716 very complex or very keen on tracking you (and have mechanisms in place that
7717 make them unusable for people who avoid being tracked). We will simply use
7721 > alias instead of stating the list
7722 of actions explicitly:</P
7732 >##########################################################################
7733 # Exceptions for sites that'll break under the default action set:
7734 ##########################################################################
7736 # "Fragile" Use a minimum set of actions for these sites (see alias above):
7739 .office.microsoft.com # surprise, surprise!
7740 .windowsupdate.microsoft.com
7741 mail.google.com</PRE
7747 > Shopping sites are not as fragile, but they typically
7748 require cookies to log in, and pop-up windows for shopping
7749 carts or item details. Again, we'll use a pre-defined alias:</P
7763 .worldpay.com # for quietpc.com
7774 HREF="actions-file.html#FAST-REDIRECTS"
7778 action, which we enabled per default above, breaks some sites. So disable
7779 it for popular sites where we know it misbehaves:</P
7790 HREF="actions-file.html#FAST-REDIRECTS"
7796 .altavista.com/.*(like|url|link):http
7797 .altavista.com/trans.*urltext=http
7804 > It is important that <SPAN
7808 URLs belong to images, so that <SPAN
7815 be blocked, a substitute image can be sent, rather than an HTML page.
7816 Contacting the remote site to find out is not an option, since it
7817 would destroy the loading time advantage of banner blocking, and it
7818 would feed the advertisers (in terms of money <SPAN
7825 information). We can mark any URL as an image with the <TT
7828 HREF="actions-file.html#HANDLE-AS-IMAGE"
7832 and marking all URLs that end in a known image file extension is a
7843 >##########################################################################
7845 ##########################################################################
7847 # Define which file types will be treated as images, in case they get
7848 # blocked further down this file:
7851 HREF="actions-file.html#HANDLE-AS-IMAGE"
7854 /.*\.(gif|jpe?g|png|bmp|ico)$</PRE
7860 > And then there are known banner sources. They often use scripts to
7861 generate the banners, so it won't be visible from the URL that the
7862 request is for an image. Hence we block them <SPAN
7869 mark them as images in one go, with the help of our
7872 >+block-as-image</TT
7873 > alias defined above. (We could of
7874 course just as well use <TT
7877 HREF="actions-file.html#BLOCK"
7881 HREF="actions-file.html#HANDLE-AS-IMAGE"
7885 Remember that the type of the replacement image is chosen by the
7889 HREF="actions-file.html#SET-IMAGE-BLOCKER"
7890 >set-image-blocker</A
7893 action. Since all URLs have matched the default section with its
7897 HREF="actions-file.html#SET-IMAGE-BLOCKER"
7898 >set-image-blocker</A
7901 action before, it still applies and needn't be repeated:</P
7911 ># Known ad generators:
7916 .ad.*.doubleclick.net
7917 .a.yimg.com/(?:(?!/i/).)*$
7918 .a[0-9].yimg.com/(?:(?!/i/).)*$
7926 > One of the most important jobs of <SPAN
7930 is to block banners. Many of these can be <SPAN
7937 HREF="actions-file.html#FILTER"
7939 >{banners-by-size}</TT
7941 action, which we enabled above, and which deletes the references to banner
7942 images from the pages while they are loaded, so the browser doesn't request
7943 them anymore, and hence they don't need to be blocked here. But this naturally
7944 doesn't catch all banners, and some people choose not to use filters, so we
7945 need a comprehensive list of patterns for banner URLs here, and apply the
7949 HREF="actions-file.html#BLOCK"
7952 > action to them.</P
7954 > First comes many generic patterns, which do most of the work, by
7955 matching typical domain and path name components of banners. Then comes
7956 a list of individual patterns for specific sites, which is omitted here
7957 to keep the example short:</P
7967 >##########################################################################
7968 # Block these fine banners:
7969 ##########################################################################
7971 HREF="actions-file.html#BLOCK"
7981 /.*count(er)?\.(pl|cgi|exe|dll|asp|php[34]?)
7982 /(?:.*/)?(publicite|werbung|rekla(ma|me|am)|annonse|maino(kset|nta|s)?)/
7984 # Site-specific patterns (abbreviated):
7992 > It's quite remarkable how many advertisers actually call their banner
7998 >.com, or call the directory
7999 in which the banners are stored simply <SPAN
8003 generic patterns are surprisingly effective.</P
8005 > But being very generic, they necessarily also catch URLs that we don't want
8006 to block. The pattern <TT
8018 >.nasty-corp.com"</SPAN
8028 >.sourcefroge.net"</SPAN
8038 >l.some-provider.net."</SPAN
8040 well-known exceptions to the <TT
8043 HREF="actions-file.html#BLOCK"
8049 > Note that these are exceptions to exceptions from the default! Consider the URL
8052 >"downloads.sourcefroge.net"</SPAN
8053 >: Initially, all actions are deactivated,
8054 so it wouldn't get blocked. Then comes the defaults section, which matches the
8055 URL, but just deactivates the <TT
8058 HREF="actions-file.html#BLOCK"
8062 action once again. Then it matches <TT
8065 >, an exception to the
8066 general non-blocking policy, and suddenly
8070 HREF="actions-file.html#BLOCK"
8073 > applies. And now, it'll match
8080 HREF="actions-file.html#BLOCK"
8084 applies, so (unless it matches <SPAN
8090 > further down) it ends up
8094 HREF="actions-file.html#BLOCK"
8097 > action applying.</P
8107 >##########################################################################
8108 # Save some innocent victims of the above generic block patterns:
8109 ##########################################################################
8114 HREF="actions-file.html#BLOCK"
8117 adv[io]*. # (for advogato.org and advice.*)
8118 adsl. # (has nothing to do with ads)
8119 adobe. # (has nothing to do with ads either)
8120 ad[ud]*. # (adult.* and add.*)
8121 .edu # (universities don't host banners (yet!))
8122 .*loads. # (downloads, uploads etc)
8130 www.globalintersec.com/adv # (adv = advanced)
8131 www.ugu.com/sui/ugu/adv</PRE
8137 > Filtering source code can have nasty side effects,
8138 so make an exception for our friends at sourceforge.net,
8139 and all paths with <SPAN
8142 > in them. Note that
8146 HREF="actions-file.html#FILTER"
8156 > filters in one fell swoop!</P
8166 ># Don't filter code!
8169 HREF="actions-file.html#FILTER"
8176 .sourceforge.net</PRE
8185 > is of course much more
8186 comprehensive, but we hope this example made clear how it works.</P
8194 >8.7.2. user.action</A
8197 > So far we are painting with a broad brush by setting general policies,
8198 which would be a reasonable starting point for many people. Now,
8199 you might want to be more specific and have customized rules that
8200 are more suitable to your personal habits and preferences. These would
8201 be for narrowly defined situations like your ISP or your bank, and should
8205 >, which is parsed after all other
8206 actions files and hence has the last word, over-riding any previously
8207 defined actions. <TT
8217 > place for your personal settings, since
8221 > is actively maintained by the
8225 > developers and you'll probably want
8226 to install updated versions from time to time.</P
8228 > So let's look at a few examples of things that one might typically do in
8242 ># My user.action file. <fred@example.com></PRE
8249 HREF="actions-file.html#ALIASES"
8251 > are local to the actions
8252 file that they are defined in, you can't use the ones from
8256 >, unless you repeat them here:</P
8266 ># Aliases are local to the file they are defined in.
8267 # (Re-)define aliases for this file:
8271 # These aliases just save typing later, and the alias names should
8272 # be self explanatory.
8274 +crunch-all-cookies = +crunch-incoming-cookies +crunch-outgoing-cookies
8275 -crunch-all-cookies = -crunch-incoming-cookies -crunch-outgoing-cookies
8276 allow-all-cookies = -crunch-all-cookies -session-cookies-only
8277 allow-popups = -filter{all-popups} -kill-popups
8278 +block-as-image = +block +handle-as-image
8279 -block-as-image = -block
8281 # These aliases define combinations of actions that are useful for
8282 # certain types of sites:
8284 fragile = -block -crunch-all-cookies -filter -fast-redirects -hide-referrer -kill-popups
8285 shop = -crunch-all-cookies allow-popups
8287 # Allow ads for selected useful free sites:
8289 allow-ads = -block -filter{banners-by-size} -filter{banners-by-link}
8291 # Alias for specific file types that are text, but might have conflicting
8292 # MIME types. We want the browser to force these to be text documents.
8293 handle-as-text = -<A
8294 HREF="actions-file.html#FILTER"
8297 HREF="actions-file.html#CONTENT-TYPE-OVERWRITE"
8298 >content-type-overwrite{text/plain}</A
8300 HREF="actions-file.html#FORCE-TEXT-MODE"
8303 HREF="actions-file.html#HIDE-CONTENT-DISPOSITION"
8304 >hide-content-disposition</A
8311 > Say you have accounts on some sites that you visit regularly, and
8312 you don't want to have to log in manually each time. So you'd like
8313 to allow persistent cookies for these sites. The
8316 >allow-all-cookies</TT
8317 > alias defined above does exactly
8318 that, i.e. it disables crunching of cookies in any direction, and the
8319 processing of cookies to make them only temporary.</P
8329 >{ allow-all-cookies }
8339 > Your bank is allergic to some filter, but you don't know which, so you disable them all:</P
8350 HREF="actions-file.html#FILTER"
8353 .your-home-banking-site.com</PRE
8359 > Some file types you may not want to filter for various reasons:</P
8369 ># Technical documentation is likely to contain strings that might
8370 # erroneously get altered by the JavaScript-oriented filters:
8375 # And this stupid host sends streaming video with a wrong MIME type,
8376 # so that Privoxy thinks it is getting HTML and starts filtering:
8378 stupid-server.example.com/</PRE
8384 > Example of a simple <A
8385 HREF="actions-file.html#BLOCK"
8387 > action. Say you've
8388 seen an ad on your favourite page on example.com that you want to get rid of.
8389 You have right-clicked the image, selected <SPAN
8391 >"copy image location"</SPAN
8393 and pasted the URL below while removing the leading http://, into a
8397 > section. Note that <TT
8401 > need not be specified, since all URLs ending in
8405 > will be tagged as images by the general rules as set
8406 in default.action anyway:</P
8417 HREF="actions-file.html#BLOCK"
8420 www.example.com/nasty-ads/sponsor\.gif
8421 another.example.net/more/junk/here/</PRE
8427 > The URLs of dynamically generated banners, especially from large banner
8428 farms, often don't use the well-known image file name extensions, which
8429 makes it impossible for <SPAN
8433 the file type just by looking at the URL.
8436 >+block-as-image</TT
8437 > alias defined above for
8439 Note that objects which match this rule but then turn out NOT to be an
8440 image are typically rendered as a <SPAN
8442 >"broken image"</SPAN
8444 browser. Use cautiously.</P
8454 >{ +block-as-image }
8464 > Now you noticed that the default configuration breaks Forbes Magazine,
8465 but you were too lazy to find out which action is the culprit, and you
8466 were again too lazy to give <A
8470 you just used the <TT
8473 > alias on the site, and
8480 > -- it worked. The <TT
8484 aliases disables those actions that are most likely to break a site. Also,
8485 good for testing purposes to see if it is <SPAN
8489 that is causing the problem or not. We later find other regular sites
8490 that misbehave, and add those to our personalized list of troublemakers:</P
8509 > You like the <SPAN
8512 > text replacements in <TT
8516 but it is disabled in the distributed actions file.
8517 So you'd like to turn it on in your private,
8518 update-safe config, once and for all:</P
8529 HREF="actions-file.html#FILTER-FUN"
8532 / # For ALL sites!</PRE
8538 > Note that the above is not really a good idea: There are exceptions
8539 to the filters in <TT
8543 really shouldn't be filtered, like code on CVS->Web interfaces. Since
8547 > has the last word, these exceptions
8548 won't be valid for the <SPAN
8551 > filtering specified here.</P
8553 > You might also worry about how your favourite free websites are
8554 funded, and find that they rely on displaying banner advertisements
8555 to survive. So you might want to specifically allow banners for those
8556 sites that you feel provide value to you:</P
8578 > has been aliased to
8582 HREF="actions-file.html#BLOCK"
8589 HREF="actions-file.html#FILTER-BANNERS-BY-SIZE"
8590 >filter{banners-by-size}</A
8596 HREF="actions-file.html#FILTER-BANNERS-BY-LINK"
8597 >filter{banners-by-link}</A
8601 > Invoke another alias here to force an over-ride of the MIME type <TT
8603 > application/x-sh</TT
8604 > which typically would open a download type
8605 dialog. In my case, I want to look at the shell script, and then I can save
8606 it should I choose to.</P
8626 > is generally the best place to define
8627 exceptions and additions to the default policies of
8631 >. Some actions are safe to have their
8632 default policies set here though. So let's set a default policy to have a
8636 > image as opposed to the checkerboard pattern for
8646 > of course matches all URL
8647 paths and patterns:</P
8658 HREF="actions-file.html#SET-IMAGE-BLOCKER"
8659 >set-image-blocker{blank}</A
8674 SUMMARY="Footer navigation table"
8703 HREF="filter-file.html"
8713 >The Main Configuration File</TD
projects / privoxy.git / blob