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42 <a name="CONFIGURATION">3. Configuration</a>
46 <a name="ACTIONSFILE">3.1. What exactly is an <span class=
47 "QUOTE">"actions"</span> file?</a>
50 <span class="APPLICATION">Privoxy</span> utilizes the concept of
51 <span class="QUOTE">" <a href=
52 "../user-manual/actions-file.html#ACTIONS" target=
53 "_top">actions</a>"</span> that are used to manipulate and control
54 web page data. <a href="../user-manual/actions-file.html" target=
55 "_top">Actions files</a> are where these <a href=
56 "../user-manual/actions-file.html#ACTIONS" target=
57 "_top">actions</a> that <span class="APPLICATION">Privoxy</span>
58 could take while processing a certain request, are configured.
59 Typically, you would define a set of default actions that apply
60 globally to all URLs, then add exceptions to these defaults where
61 needed. There is a wide array of actions available that give the
62 user a high degree of control and flexibility on how to process
63 each and every web page.
66 Actions can be defined on a <a href=
67 "../user-manual/actions-file.html#AF-PATTERNS" target="_top">URL
68 pattern</a> basis, i.e. for single URLs, whole web sites, groups or
69 parts thereof etc. Actions can also be grouped together and then
70 applied to requests matching one or more patterns. There are many
71 possible actions that might apply to any given site. As an example,
72 if you are blocking <a href=
73 "http://en.wikipedia.org/wiki/Browser_cookie" target=
74 "_top">cookies</a> as one of your default actions, but need to
75 accept cookies from a given site, you would need to define an
76 exception for this site in one of your actions files, preferably in
77 <tt class="FILENAME">user.action</tt>.
82 <a name="ACTIONSS">3.2. The <span class="QUOTE">"actions"</span>
83 concept confuses me. Please list some of these <span class=
84 "QUOTE">"actions"</span>.</a>
87 For a comprehensive discussion of the actions concept, please refer
88 to the <a href="../user-manual/actions-file.html" target=
89 "_top">actions file chapter</a> in the <a href=
90 "../user-manual/index.html" target="_top">User Manual</a>. It
91 includes a <a href="../user-manual/actions-file.html#ACTIONS"
92 target="_top">list of all actions</a> and an <a href=
93 "../user-manual/actions-file.html#ACT-EXAMPLES" target=
94 "_top">actions file tutorial</a> to get you started.
99 <a name="ACTCONFIG">3.3. How are actions files configured? What is
100 the easiest way to do this?</a>
103 Actions files are just text files in a special syntax and can be
104 edited with a text editor. But probably the easiest way is to
105 access <span class="APPLICATION">Privoxy</span>'s user interface
106 with your web browser at <a href="http://config.privoxy.org/"
107 target="_top">http://config.privoxy.org/</a> (Shortcut: <a href=
108 "http://p.p/" target="_top">http://p.p/</a>) and then select <span
109 class="QUOTE">"<a href="http://config.privoxy.org/show-status"
110 target="_top">View & change the current
111 configuration</a>"</span> from the menu. Note that this feature
112 must be explicitly enabled in the main config file (see <a href=
113 "../user-manual/config.html#ENABLE-EDIT-ACTIONS" target=
114 "_top">enable-edit-actions</a>).
119 <a name="AEN418">3.4. There are several different <span class=
120 "QUOTE">"actions"</span> files. What are the differences?</a>
123 Please have a look at the <a href=
124 "../user-manual/actions-file.html" target="_top">the actions
125 chapter</a> in the <a href="../user-manual/index.html" target=
126 "_top">User Manual</a> for a detailed explanation.
131 <a name="GETUPDATES">3.5. Where can I get updated Actions
135 Based on your feedback and the continuing development, updates of
136 <tt class="FILENAME">default.action</tt> will be made available
137 from time to time on the <a href=
138 "https://sourceforge.net/project/showfiles.php?group_id=11118"
139 target="_top">files section</a> of our <a href=
140 "https://sourceforge.net/projects/ijbswa/" target="_top">project
144 If you wish to receive an email notification whenever we release
145 updates of <span class="APPLICATION">Privoxy</span> or the actions
147 "https://lists.privoxy.org/mailman/listinfo/privoxy-announce"
148 target="_top">subscribe to our announce mailing list</a>,
149 privoxy-announce@lists.privoxy.org.
154 <a name="NEWCONFIG">3.6. Can I use my old config files?</a>
157 The syntax and purpose of configuration files has remained roughly
158 the same throughout the 3.x series, but backwards compatibility is
159 not guaranteed. Also each release contains updated, <span class=
160 "QUOTE">"improved"</span> versions and it is therefore strongly
161 recommended to install the newer configuration files and merge back
167 <a name="DIFFICULT">3.7. Why is the configuration so
171 <span class="QUOTE">"Complicated"</span> is in the eye of the
175 Privoxy is currently mainly written by and for people who are
176 already familiar with the underlying concepts like regular
177 expressions, HTTP and HTML, or are willing to become familiar with
178 them to be able to get the most out of a powerful and flexible tool
182 While everybody is expected to be able to get a Privoxy default
183 installation up and running, fine-tuning requires a certain amount
184 of background information and Privoxy's documentation mainly
185 concentrates on the Privoxy-specific parts while only providing
186 references to the rest.
189 If you or anyone you know has the skills, time and energy to reduce
190 the barrier of entry, please <a href="general.html#PARTICIPATE">get
196 <a name="YAHOO">3.8. How can I make my Yahoo/Hotmail/Gmail account
200 The default configuration shouldn't impact the usability of any of
201 these services. It may, however, make all <a href=
202 "http://en.wikipedia.org/wiki/Browser_cookie" target=
203 "_top">cookies</a> temporary, so that your browser will forget your
204 login credentials in between browser sessions. If you would like
205 not to have to log in manually each time you access those websites,
206 simply turn off all cookie handling for them in the <tt class=
207 "FILENAME">user.action</tt> file. An example for yahoo might look
212 <table border="0" bgcolor="#E0E0E0" width="100%">
216 # Allow all cookies for Yahoo login:
218 { -<a href="../user-manual/actions-file.html#CRUNCH-INCOMING-COOKIES" target=
219 "_top">crunch-incoming-cookies</a> -<a href=
220 "../user-manual/actions-file.html#CRUNCH-OUTGOING-COOKIES" target=
221 "_top">crunch-outgoing-cookies</a> -<a href=
222 "../user-manual/actions-file.html#SESSION-COOKIES-ONLY" target=
223 "_top">session-cookies-only</a> }
231 These kinds of sites are often quite complex and heavy with <a
232 href="http://en.wikipedia.org/wiki/Javascript" target=
233 "_top">Javascript</a> and thus <span class=
234 "QUOTE">"fragile"</span>. So if <span class="emphasis"><i class=
235 "EMPHASIS">still</i></span> a problem, we have an <a href=
236 "../user-manual/actions-file.html#ALIASES" target="_top">alias</a>
237 just for such sticky situations:
241 <table border="0" bgcolor="#E0E0E0" width="100%">
245 # Gmail is a _fragile_ site:
247 { <tt class="LITERAL">fragile</tt> }
256 Be sure to flush your browser's caches whenever making these kinds
257 of changes, just to make sure the changes <span class=
258 "QUOTE">"take"</span>.
261 Make sure the domain, host and path are appropriate as well. Your
262 browser can tell you where you are specifically and you should use
263 that information for your configuration settings. Note that above
264 it is not referenced as <tt class="LITERAL">gmail.com</tt>, which
265 is a valid domain name.
270 <a name="CONFIGFILES">3.9. What's the difference between the <span
271 class="QUOTE">"Cautious"</span>, <span class=
272 "QUOTE">"Medium"</span> and <span class="QUOTE">"Advanced"</span>
276 Configuring <span class="APPLICATION">Privoxy</span> is not
277 entirely trivial. To help you get started, we provide you with
278 three different default action <span class=
279 "QUOTE">"profiles"</span> in the web based actions file editor at
280 <a href="http://config.privoxy.org/show-status" target=
281 "_top">http://config.privoxy.org/show-status</a>. See the <a href=
282 "../user-manual/actions-file.html" target="_top"><i class=
283 "CITETITLE">User Manual</i></a> for a list of actions, and how the
284 default profiles are set.
287 Where the defaults are likely to break some sites, exceptions for
288 known popular <span class="QUOTE">"problem"</span> sites are
289 included, but in general, the more aggressive your default settings
290 are, the more exceptions you will have to make later. New users are
291 best to start off in <span class="QUOTE">"Cautious"</span> setting.
292 This is safest and will have the fewest problems. See the <a href=
293 "../user-manual/index.html" target="_top"><i class="CITETITLE">User
294 Manual</i></a> for a more detailed discussion.
297 It should be noted that the <span class="QUOTE">"Advanced"</span>
298 profile (formerly known as the <span class=
299 "QUOTE">"Adventuresome"</span> profile) is more aggressive, and
300 will make use of some of <span class="APPLICATION">Privoxy's</span>
301 advanced features. Use at your own risk!
306 <a name="BROWSECONFIG">3.10. Why can I change the configuration
307 with a browser? Does that not raise security issues?</a>
310 It may seem strange that regular users can edit the config files
311 with their browsers, although the whole <tt class=
312 "FILENAME">/etc/privoxy</tt> hierarchy belongs to the user <span
313 class="QUOTE">"privoxy"</span>, with only 644 permissions.
316 When you use the browser-based editor, <span class=
317 "APPLICATION">Privoxy</span> itself is writing to the config files.
318 Because <span class="APPLICATION">Privoxy</span> is running as the
319 user <span class="QUOTE">"privoxy"</span>, it can update its own
323 If you run <span class="APPLICATION">Privoxy</span> for multiple
324 untrusted users (e.g. in a LAN) or aren't entirely in control of
325 your own browser, you will probably want to make sure that the
326 web-based editor and remote toggle features are <span class=
327 "QUOTE">"off"</span> by setting <span class="QUOTE">"<tt class=
328 "LITERAL"><a href="../user-manual/config.html#ENABLE-EDIT-ACTIONS"
329 target="_top">enable-edit-actions</a> 0</tt>"</span> and <span
330 class="QUOTE">"<tt class="LITERAL"><a href=
331 "../user-manual/config.html#ENABLE-REMOTE-TOGGLE" target=
332 "_top">enable-remote-toggle</a> 0</tt>"</span> in the <a href=
333 "../user-manual/config.html" target="_top">main configuration
337 As of <span class="APPLICATION">Privoxy</span> 3.0.7 these options
338 are disabled by default.
343 <a name="FILTERFILE">3.11. What is the <tt class=
344 "FILENAME">default.filter</tt> file? What is a <span class=
345 "QUOTE">"filter"</span>?</a>
348 The <a href="../user-manual/filter-file.html" target="_top"><tt
349 class="FILENAME">default.filter</tt></a> file is where <span class=
350 "emphasis"><i class="EMPHASIS">filters</i></span> as supplied by
351 the developers are defined. Filters are a special subset of actions
352 that can be used to modify or remove web page content or headers on
353 the fly. Content filters can be applied to <span class=
354 "emphasis"><i class="EMPHASIS">anything</i></span> in the page
355 source, header filters can be applied to either server or client
356 headers. Regular expressions are used to accomplish this.
359 There are a number of pre-defined filters to deal with common
360 annoyances. The filters are only defined here, to invoke them, you
361 need to use the <a href="../user-manual/actions-file.html#FILTER"
362 target="_top"><tt class="LITERAL">filter</tt> action</a> in one of
363 the actions files. Content filtering is automatically disabled for
364 inappropriate MIME types, but if you know better than Privoxy what
365 should or should not be filtered you can filter any content you
369 Filters should <span class="emphasis"><i class=
370 "EMPHASIS">not</i></span> be confused with <a href=
371 "../user-manual/actions-file.html#BLOCK" target="_top"><tt class=
372 "LITERAL">blocks</tt></a>, which is a completely different action,
373 and is more typically used to block ads and unwanted sites.
376 If you are familiar with regular expressions, and HTML, you can
377 look at the provided <tt class="FILENAME">default.filter</tt> with
378 a text editor and define your own filters. This is potentially a
379 very powerful feature, but requires some expertise in both regular
380 expressions and HTML/HTTP. You should place any modifications to
381 the default filters, or any new ones you create in a separate file,
382 such as <tt class="FILENAME">user.filter</tt>, so they won't be
383 overwritten during upgrades. The ability to define multiple filter
384 files in <tt class="FILENAME">config</tt> is a new feature as of v.
388 There is no GUI editor option for this part of the configuration,
389 but you can disable/enable the various pre-defined filters of the
390 included <tt class="FILENAME">default.filter</tt> file with the <a
391 href="http://config.privoxy.org/show-status" target=
392 "_top">web-based actions file editor</a>. Note that the custom
393 actions editor must be explicitly enabled in the main config file
394 (see <a href="../user-manual/config.html#ENABLE-EDIT-ACTIONS"
395 target="_top">enable-edit-actions</a>).
398 If you intend to develop your own filters, you might want to have a
399 look at <a href="https://www.fabiankeil.de/sourcecode/pft/" target=
400 "_top">Privoxy-Filter-Test</a>.
405 <a name="LANCONFIG">3.12. How can I set up Privoxy to act as a
406 proxy for my LAN?</a>
409 By default, <span class="APPLICATION">Privoxy</span> only responds
410 to requests from <tt class="LITERAL">127.0.0.1</tt> (localhost). To
411 have it act as a server for a network, this needs to be changed in
412 the <a href="../user-manual/config.html" target="_top">main
413 configuration file</a>. Look for the <tt class="LITERAL"><a href=
414 "../user-manual/config.html#LISTEN-ADDRESS" target=
415 "_top">listen-address</a></tt> option, which may be commented out
416 with a <span class="QUOTE">"#"</span> symbol. Make sure it is
417 uncommented, and assign it the address of the LAN gateway
418 interface, and port number to use. Assuming your LAN address is
419 192.168.1.1 and you wish to run <span class=
420 "APPLICATION">Privoxy</span> on port 8118, this line should look
425 <table border="0" bgcolor="#E0E0E0" width="100%">
429 listen-address 192.168.1.1:8118
436 Save the file, and restart <span class=
437 "APPLICATION">Privoxy</span>. Configure all browsers on the network
438 then to use this address and port number.
441 Alternately, you can have <span class="APPLICATION">Privoxy</span>
442 listen on all available interfaces:
446 <table border="0" bgcolor="#E0E0E0" width="100%">
457 And then use <span class="APPLICATION">Privoxy's</span> <a href=
458 "../user-manual/config.html#PERMIT-ACCESS" target=
459 "_top">permit-access</a> feature to limit connections. A firewall
460 in this situation is recommended as well.
463 The above steps should be the same for any TCP network, regardless
467 If you run <span class="APPLICATION">Privoxy</span> on a LAN with
468 untrusted users, we recommend that you double-check the <a href=
469 "../user-manual/config.html#ACCESS-CONTROL" target="_top">access
470 control and security</a> options!
475 <a name="NOSEEUM">3.13. Instead of ads, now I get a checkerboard
476 pattern. I don't want to see anything.</a>
479 The replacement for blocked images can be controlled with the <a
480 href="../user-manual/actions-file.html#SET-IMAGE-BLOCKER" target=
481 "_top"><tt class="LITERAL">set-image-blocker</tt> action</a>. You
482 have the choice of a checkerboard pattern, a transparent 1x1 GIF
483 image (aka <span class="QUOTE">"blank"</span>), or a redirect to a
484 custom image of your choice. Note that this choice only has effect
485 for images which are blocked as images, i.e. whose URLs match both
486 a <tt class="LITERAL"><a href=
487 "../user-manual/actions-file.html#HANDLE-AS-IMAGE" target=
488 "_top">handle-as-image</a></tt> <span class="emphasis"><i class=
489 "EMPHASIS">and</i></span> <tt class="LITERAL"><a href=
490 "../user-manual/actions-file.html#BLOCK" target=
491 "_top">block</a></tt> action.
494 If you want to see nothing, then change the <a href=
495 "../user-manual/actions-file.html#SET-IMAGE-BLOCKER" target=
496 "_top"><tt class="LITERAL">set-image-blocker</tt> action</a> to
497 <span class="QUOTE">"blank"</span>. This can be done by editing the
498 <tt class="FILENAME">user.action</tt> file, or through the <a href=
499 "http://config.privoxy.org/show-status" target="_top">web-based
500 actions file editor</a>.
505 <a name="WHYSEEUM">3.14. Why would anybody want to see a
506 checkerboard pattern?</a>
509 Remember that <a href="general.html#WHATSANAD">telling which image
510 is an ad and which isn't</a>, is an educated guess. While we hope
511 that the standard configuration is rather smart, it will make
512 occasional mistakes. The checkerboard image is visually decent, and
513 it shows you where images have been blocked, which can be very
514 helpful in case some navigation aid or otherwise innocent image was
515 erroneously blocked. It is recommended for new users so they can
516 <span class="QUOTE">"see"</span> what is happening. Some people
517 might also enjoy seeing how many banners they <span class=
518 "emphasis"><i class="EMPHASIS">don't</i></span> have to see.
523 <a name="BLOCKEDBYTEXT">3.15. I see some images being replaced with
524 text instead of the checkerboard image. Why and how do I get rid of
528 This happens when the banners are not embedded in the HTML code of
529 the page itself, but in separate HTML (sub)documents that are
530 loaded into (i)frames or (i)layers, and these external HTML
531 documents are blocked. Being non-images they get replaced by a
532 substitute HTML page rather than a substitute image, which wouldn't
533 work out technically, since the browser expects and accepts only
534 HTML when it has requested an HTML document.
537 The substitute page adapts to the available space and shows itself
538 as a miniature two-liner if loaded into small frames, or full-blown
539 with a large red "BLOCKED" banner if space allows.
542 If you prefer the banners to be blocked by images, you must see to
543 it that the HTML documents in which they are embedded are not
544 blocked. Clicking the <span class="QUOTE">"See why"</span> link
545 offered in the substitute page will show you which rule blocked the
546 page. After changing the rule and un-blocking the HTML documents,
547 the browser will try to load the actual banner images and the usual
548 image blocking will (hopefully!) kick in.
553 <a name="SRVANY">3.16. Can Privoxy run as a service on
557 Yes. Version 3.0.5 introduces full <span class=
558 "APPLICATION">Windows</span> service functionality. See <a href=
559 "../user-manual/installation.html#installation-pack-win" target=
560 "_top">the <i class="CITETITLE">User Manual</i></a> for details on
561 how to install and configure <span class=
562 "APPLICATION">Privoxy</span> as a service.
565 Earlier 3.x versions could run as a system service using <b class=
566 "COMMAND">srvany.exe</b>. See the discussion at <a href=
567 "https://sourceforge.net/tracker/?func=detail&atid=361118&aid=485617&group_id=11118"
569 "_top">https://sourceforge.net/tracker/?func=detail&atid=361118&aid=485617&group_id=11118</a>,
570 for details, and a sample configuration.
575 <a name="OTHERPROXY">3.17. How can I make Privoxy work with other
579 This can be done and is often useful to combine the benefits of
580 <span class="APPLICATION">Privoxy</span> with those of a another
581 proxy, for example to cache content. See the <a href=
582 "../user-manual/config.html#FORWARDING" target="_top">forwarding
583 chapter</a> in the <a href="../user-manual/index.html" target=
584 "_top">User Manual</a> which describes how to do this. If you
585 intend to use Privoxy with Tor, please also have a look at <a href=
586 "misc.html#TOR">How do I use Privoxy together with Tor</a>.
591 <a name="PORT-80">3.18. Can I just set Privoxy to use port 80 and
592 thus avoid individual browser configuration?</a>
595 No, its more complicated than that. This only works with special
596 kinds of proxies known as <span class="QUOTE">"intercepting"</span>
597 proxies (<a href="configuration.html#INTERCEPTING">see below</a>).
602 <a name="TRANSPARENT">3.19. Can Privoxy run as a <span class=
603 "QUOTE">"transparent"</span> proxy?</a>
606 The whole idea of Privoxy is to modify client requests and server
607 responses in all sorts of ways and therefore it's not a transparent
608 proxy as described in <a href="http://tools.ietf.org/html/rfc2616"
609 target="_top">RFC 2616</a>.
612 However, some people say <span class="QUOTE">"transparent
613 proxy"</span> when they mean <span class="QUOTE">"intercepting
614 proxy"</span>. If you are one of them, please read the <a href=
615 "configuration.html#INTERCEPTING">next entry</a>.
620 <a name="INTERCEPTING">3.20. Can Privoxy run as a <span class=
621 "QUOTE">"intercepting"</span> proxy?</a>
624 <span class="APPLICATION">Privoxy</span> can't intercept traffic
625 itself, but it can handle requests that where intercepted and
626 redirected with a packet filter (like <span class=
627 "APPLICATION">PF</span> or <span class=
628 "APPLICATION">iptables</span>), as long as the <tt class=
629 "LITERAL">Host</tt> header is present.
632 As the <tt class="LITERAL">Host</tt> header is required by HTTP/1.1
633 and as most web sites rely on it anyway, this limitation shouldn't
637 Please refer to your packet filter's documentation to learn how to
638 intercept and redirect traffic into <span class=
639 "APPLICATION">Privoxy</span>. Afterward you just have to configure
640 <span class="APPLICATION">Privoxy</span> to <a href=
641 "../user-manual/config.html#ACCEPT-INTERCEPTED-REQUESTS" target=
642 "_top">accept intercepted requests</a>.
647 <a name="OUTLOOK">3.21. How can I configure Privoxy for use with
651 Versions of <span class="APPLICATION">Outlook</span> prior to
652 Office 2007, use <span class="APPLICATION">Internet Explorer</span>
653 components to both render HTML, and fetch any HTTP requests that
654 may be embedded in an HTML email. So however you have <span class=
655 "APPLICATION">Privoxy</span> configured to work with IE, this
656 configuration should automatically be shared, at least with older
657 version of Internet Explorer.
660 Starting with Office 2007, Microsoft is instead using the MS-Word
661 rendering engine with Outlook. It is unknown whether this can be
662 configured to use a proxy.
667 <a name="OUTLOOK-MORE">3.22. How can I have separate rules just for
671 The short answer is, you can't. <span class=
672 "APPLICATION">Privoxy</span> has no way of knowing which particular
673 application makes a request, so there is no way to distinguish
674 between web pages and HTML mail. <span class=
675 "APPLICATION">Privoxy</span> just blindly proxies all requests. In
676 the case of <span class="APPLICATION">Outlook Express</span> (see
677 above), OE uses IE anyway, and there is no way for <span class=
678 "APPLICATION">Privoxy</span> to ever be able to distinguish between
679 them (nor could any other proxy type application for that matter).
682 For a good discussion of some of the issues involved (including
683 privacy and security issues), see <a href=
684 "https://sourceforge.net/tracker/?func=detail&atid=211118&aid=629518&group_id=11118"
686 "_top">https://sourceforge.net/tracker/?func=detail&atid=211118&aid=629518&group_id=11118</a>.
691 <a name="SNEAKY-COOKIES">3.23. I sometimes notice cookies sneaking
695 <a href="http://en.wikipedia.org/wiki/Browser_cookie" target=
696 "_top">Cookies</a> can be set in several ways. The classic method
697 is via the <tt class="LITERAL">Set-Cookie</tt> HTTP header. This is
698 straightforward, and an easy one to manipulate, such as the <span
699 class="APPLICATION">Privoxy</span> concept of <a href=
700 "../user-manual/actions-file.html#SESSION-COOKIES-ONLY" target=
701 "_top">session-cookies-only</a>. There is also the possibility of
702 using <a href="http://en.wikipedia.org/wiki/Javascript" target=
703 "_top">Javascript</a> to set cookies (<span class=
704 "APPLICATION">Privoxy</span> calls these <tt class=
705 "LITERAL">content-cookies</tt>). This is trickier because the
706 syntax can vary widely, and thus requires a certain amount of
707 guesswork. It is not realistic to catch all of these short of
708 disabling Javascript, which would break many sites. And lastly, if
709 the cookies are embedded in a HTTPS/SSL secure session via
710 Javascript, they are beyond <span class=
711 "APPLICATION">Privoxy's</span> reach.
714 All in all, <span class="APPLICATION">Privoxy</span> can help
715 manage cookies in general, can help minimize the loss of privacy
716 posed by cookies, but can't realistically stop all cookies.
721 <a name="EVIL-COOKIES">3.24. Are all cookies bad? Why?</a>
724 No, in fact there are many beneficial uses of <a href=
725 "http://en.wikipedia.org/wiki/Browser_cookie" target=
726 "_top">cookies</a>. Cookies are just a method that browsers can use
727 to store data between pages, or between browser sessions. Sometimes
728 there is a good reason for this, and the user's life is a bit
729 easier as a result. But there is a long history of some websites
730 taking advantage of this layer of trust, and using the data they
731 glean from you and your browsing habits for their own purposes, and
732 maybe to your potential detriment. Such sites are using you and
733 storing their data on your system. That is why the privacy
734 conscious watch from whom those cookies come, and why they really
735 <span class="emphasis"><i class="EMPHASIS">need</i></span> to be
739 See the <a href="http://en.wikipedia.org/wiki/Browser_cookie"
740 target="_top">Wikipedia cookie definition</a> for more.
745 <a name="ALLOW-COOKIES">3.25. How can I allow permanent cookies for
746 my trusted sites?</a>
749 There are several actions that relate to cookies. The default
750 behavior is to allow only <span class="QUOTE">"session
751 cookies"</span>, which means the cookies only last for the current
752 browser session. This eliminates most kinds of abuse related to
753 cookies. But there may be cases where you want cookies to last.
756 To disable all cookie actions, so that cookies are allowed
757 unrestricted, both in and out, for <tt class=
758 "LITERAL">example.com</tt>:
762 <table border="0" bgcolor="#E0E0E0" width="100%">
766 { -crunch-incoming-cookies -crunch-outgoing-cookies -session-cookies-only -filter{content-cookies} }
774 Place the above in <tt class="FILENAME">user.action</tt>. Note that
775 some of these may be off by default anyway, so this might be
776 redundant, but there is no harm being explicit in what you want to
777 happen. <tt class="FILENAME">user.action</tt> includes an alias for
778 this situation, called <tt class="LITERAL">allow-all-cookies</tt>.
783 <a name="MULTIPLES">3.26. Can I have separate configurations for
787 Each instance of <span class="APPLICATION">Privoxy</span> has its
788 own configuration, including such attributes as the TCP port that
789 it listens on. What you can do is run multiple instances of <span
790 class="APPLICATION">Privoxy</span>, each with a unique <a href=
791 "../user-manual/config.html#LISTEN-ADDRESS" target=
792 "_top">listen-address</a> configuration setting, and configuration
793 path, and then each of these can have their own configurations.
794 Think of it as per-port configuration.
797 Simple enough for a few users, but for large installations,
798 consider having groups of users that might share like
804 <a name="WHITELISTS">3.27. Can I set-up Privoxy as a whitelist of
805 <span class="QUOTE">"good"</span> sites?</a>
808 Sure. There are a couple of things you can do for simple
809 white-listing. Here's one real easy one:
811 <table border="0" bgcolor="#E0E0E0" width="100%">
815 ############################################################
817 ############################################################
818 { <a href="../user-manual/actions-file.html#BLOCK" target=
822 ############################################################
824 ############################################################
825 { <a href="../user-manual/actions-file.html#BLOCK" target=
835 This allows access to only those three sites by first blocking all
836 URLs, and then subsequently allowing three specific exceptions.
839 Another approach is <span class="APPLICATION">Privoxy's</span> <tt
840 class="LITERAL">trustfile</tt> concept, which incorporates the
841 notion of <span class="QUOTE">"trusted referrers"</span>. See the
842 <a href="../user-manual/config.html#TRUSTFILE" target="_top">Trust
843 documentation</a> for details.
846 These are fairly simple approaches and are not completely
847 foolproof. There are various other configuration options that
848 should be disabled (described elsewhere here and in <a href=
849 "../user-manual/" target="_top">the User Manual</a>) so that users
850 can't modify their own configuration and easily circumvent the
856 <a name="NO-ADBLOCK">3.28. How can I turn off ad-blocking?</a>
859 Ad blocking is achieved through a complex application of various
860 <span class="APPLICATION">Privoxy</span> <a href=
861 "../user-manual/actions-file.html" target="_top">actions</a>. These
862 actions are deployed against simple images, banners, flash
863 animations, text pages, JavaScript, pop-ups and pop-unders, etc.,
864 so its not as simple as just turning one or two actions off. The
865 various actions that make up <span class=
866 "APPLICATION">Privoxy</span> ad blocking are hard-coded into the
867 default configuration files. It has been assumed that everyone
868 using <span class="APPLICATION">Privoxy</span> is interested in
869 this particular feature.
872 If you want to do without this, there are several approaches you
873 can take: You can manually undo the many block rules in <tt class=
874 "FILENAME">default.action</tt>. Or even easier, just create your
875 own <tt class="FILENAME">default.action</tt> file from scratch
876 without the many ad blocking rules, and corresponding exceptions.
877 Or lastly, if you are not concerned about the additional blocks
878 that are done for privacy reasons, you can very easily over-ride
879 <span class="emphasis"><i class="EMPHASIS">all</i></span> blocking
880 with the following very simple rule in your <tt class=
881 "FILENAME">user.action</tt>:
885 <table border="0" bgcolor="#E0E0E0" width="100%">
889 # Unblock everybody, everywhere
890 { <a href="../user-manual/actions-file.html#BLOCK" target=
892 / # UN-Block *all* URLs
899 Or even a more comprehensive reversing of various ad related
904 <table border="0" bgcolor="#E0E0E0" width="100%">
908 # Unblock everybody, everywhere, and turn off appropriate filtering, etc
909 { <a href="../user-manual/actions-file.html#BLOCK" target=
911 <a href="../user-manual/actions-file.html#FILTER-BANNERS-BY-SIZE" target=
912 "_top">-filter{banners-by-size}</a> \
913 <a href="../user-manual/actions-file.html#FILTER-BANNERS-BY-LINK" target=
914 "_top">-filter{banners-by-link}</a> \
915 <tt class="LITERAL">allow-popups</tt> \
917 / # UN-Block *all* URLs and allow ads
924 This last <span class="QUOTE">"action"</span> in this compound
925 statement, <tt class="LITERAL">allow-popups</tt>, is an <a href=
926 "../user-manual/actions-file.html#ALIASES" target="_top">alias</a>
927 that disables various pop-up blocking features.
932 <a name="TEMPLATES">3.29. How can I have custom template pages,
933 like the <span class="emphasis"><i class=
934 "EMPHASIS">BLOCKED</i></span> page?</a>
937 <span class="APPLICATION">Privoxy</span> <span class=
938 "QUOTE">"templates"</span> are specialized text files utilized by
939 <span class="APPLICATION">Privoxy</span> for various purposes and
940 can easily be modified using any text editor. All the template
941 pages are installed in a sub-directory appropriately named: <tt
942 class="FILENAME">templates</tt>. Knowing something about HTML
943 syntax will of course be helpful.
946 Be forewarned that the default templates are subject to being
947 overwritten during upgrades. You can, however, create completely
948 new templates, place them in another directory and specify the
949 alternate path in the main <tt class="FILENAME">config</tt>. For
950 details, have a look at the <a href=
951 "../user-manual/config.html#templdir" target="_top">templdir</a>
957 <a name="BLOCKALL">3.30. How can I remove the <span class=
958 "QUOTE">"Go There Anyway"</span> link from the <span class=
959 "emphasis"><i class="EMPHASIS">BLOCKED</i></span> page?</a>
962 There is more than one way to do it (although Perl is not
966 Editing the BLOCKED template page (see above) may dissuade some
967 users, but this method is easily circumvented. Where you need this
968 level of control, you might want to build <span class=
969 "APPLICATION">Privoxy</span> from source, and disable various
970 features that are available as compile-time options. You should <b
971 class="COMMAND">configure</b> the sources as follows:
975 <table border="0" bgcolor="#E0E0E0" width="100%">
979 ./configure --disable-toggle --disable-editor --disable-force
986 This will create an executable with hard-coded security features so
987 that <span class="APPLICATION">Privoxy</span> does not allow easy
988 bypassing of blocked sites, or changing the current configuration
989 via any connected user's web browser.
992 Finally, all of these features can also be toggled on/off via
993 options in <span class="APPLICATION">Privoxy's</span> main <a href=
994 "../user-manual/config.html#ACCESS-CONTROL" target=
995 "_top">config</a> file which means you don't have to recompile
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