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52 <a name="CONFIGURATION">3. Configuration</a>
56 <a name="AEN360">3.1. What exactly is an <span class=
57 "QUOTE">"actions"</span> file?</a>
60 <span class="APPLICATION">Privoxy</span> utilizes the concept of
61 <span class="QUOTE">" <a href=
62 "../user-manual/actions-file.html#ACTIONS" target=
63 "_top">actions</a>"</span> that are used to manipulate and control
64 web page data. <a href="../user-manual/actions-file.html" target=
65 "_top">Actions files</a> are where these <a href=
66 "../user-manual/actions-file.html#ACTIONS" target=
67 "_top">actions</a> that <span class="APPLICATION">Privoxy</span>
68 could take while processing a certain request, are configured.
69 Typically, you would define a set of default actions that apply
70 globally to all URLs, then add exceptions to these defaults where
71 needed. There is a wide array of actions available that give the
72 user a high degree of control and flexibility on how to process
73 each and every web page.
76 Actions can be defined on a <a href=
77 "../user-manual/actions-file.html#AF-PATTERNS" target="_top">URL
78 pattern</a> basis, i.e. for single URLs, whole web sites, groups or
79 parts thereof etc. Actions can also be grouped together and then
80 applied to requests matching one or more patterns. There are many
81 possible actions that might apply to any given site. As an example,
82 if you are blocking <a href=
83 "http://en.wikipedia.org/wiki/Browser_cookie" target=
84 "_top">cookies</a> as one of your default actions, but need to
85 accept cookies from a given site, you would need to define an
86 exception for this site in one of your actions files, preferably in
87 <tt class="FILENAME">user.action</tt>.
92 <a name="ACTIONSS">3.2. The <span class="QUOTE">"actions"</span>
93 concept confuses me. Please list some of these <span class=
94 "QUOTE">"actions"</span>.</a>
97 For a comprehensive discussion of the actions concept, please refer
98 to the <a href="../user-manual/actions-file.html" target=
99 "_top">actions file chapter</a> in the <a href=
100 "../user-manual/index.html" target="_top">User Manual</a>. It
101 includes a <a href="../user-manual/actions-file.html#ACTIONS"
102 target="_top">list of all actions</a> and an <a href=
103 "../user-manual/actions-file.html#ACT-EXAMPLES" target=
104 "_top">actions file tutorial</a> to get you started.
109 <a name="AEN383">3.3. How are actions files configured? What is the
110 easiest way to do this?</a>
113 Actions files are just text files in a special syntax and can be
114 edited with a text editor. But probably the easiest way is to
115 access <span class="APPLICATION">Privoxy</span>'s user interface
116 with your web browser at <a href="http://config.privoxy.org/"
117 target="_top">http://config.privoxy.org/</a> (Shortcut: <a href=
118 "http://p.p/" target="_top">http://p.p/</a>) and then select <span
119 class="QUOTE">"<a href="http://config.privoxy.org/show-status"
120 target="_top">View & change the current
121 configuration</a>"</span> from the menu. Note that this feature
122 must be explicitly enabled in the main config file (see <a href=
123 "../user-manual/config.html#ENABLE-EDIT-ACTIONS" target=
124 "_top">enable-edit-actions</a>).
129 <a name="AEN392">3.4. There are several different <span class=
130 "QUOTE">"actions"</span> files. What are the differences?</a>
133 Please have a look at the <a href=
134 "../user-manual/actions-file.html" target="_top">the actions
135 chapter</a> in the <a href="../user-manual/index.html" target=
136 "_top">User Manual</a> for a detailed explanation.
141 <a name="GETUPDATES">3.5. Where can I get updated Actions
145 Based on your feedback and the continuing development, updates of
146 <tt class="FILENAME">default.action</tt> will be made available
147 from time to time on the <a href=
148 "http://sourceforge.net/project/showfiles.php?group_id=11118"
149 target="_top">files section</a> of our <a href=
150 "http://sf.net/projects/ijbswa/" target="_top">project page</a>.
153 If you wish to receive an email notification whenever we release
154 updates of <span class="APPLICATION">Privoxy</span> or the actions
156 "http://lists.sourceforge.net/lists/listinfo/ijbswa-announce/"
157 target="_top">subscribe to our announce mailing list</a>,
158 ijbswa-announce@lists.sourceforge.net.
163 <a name="NEWCONFIG">3.6. Can I use my old config files?</a>
166 The syntax and purpose of configuration files has remained roughly
167 the same throughout the 3.x series, but backwards compatibility is
168 not guaranteed. Also each release contains updated, <span class=
169 "QUOTE">"improved"</span> versions and it is therefore strongly
170 recommended to install the newer configuration files and merge back
176 <a name="DIFFICULT">3.7. Why is the configuration so
180 <span class="QUOTE">"Complicated"</span> is in the eye of the
181 beholder. Those that are familiar with some of the underlying
182 concepts, such as regular expression syntax, take to it like a fish
183 takes to water. Also, software that tries hard to be <span class=
184 "QUOTE">"user friendly"</span>, often lacks sophistication and
185 flexibility. There is always that trade-off there between power vs.
186 easy-of-use. Furthermore, anyone is welcome to contribute ideas and
187 implementations to enhance <span class=
188 "APPLICATION">Privoxy</span>.
193 <a name="YAHOO">3.8. How can I make my Yahoo/Hotmail/Gmail account
197 The default configuration shouldn't impact the usability of any of
198 these services. It may, however, make all <a href=
199 "http://en.wikipedia.org/wiki/Browser_cookie" target=
200 "_top">cookies</a> temporary, so that your browser will forget your
201 login credentials in between browser sessions. If you would like
202 not to have to log in manually each time you access those websites,
203 simply turn off all cookie handling for them in the <tt class=
204 "FILENAME">user.action</tt> file. An example for yahoo might look
209 <table border="0" bgcolor="#E0E0E0" width="100%">
213 # Allow all cookies for Yahoo login:
215 { -<a href="../user-manual/actions-file.html#CRUNCH-INCOMING-COOKIES" target=
216 "_top">crunch-incoming-cookies</a> -<a href=
217 "../user-manual/actions-file.html#CRUNCH-OUTGOING-COOKIES" target=
218 "_top">crunch-outgoing-cookies</a> -<a href=
219 "../user-manual/actions-file.html#SESSION-COOKIES-ONLY" target=
220 "_top">session-cookies-only</a> }
228 These kinds of sites are often quite complex and heavy with <a
229 href="http://en.wikipedia.org/wiki/Javascript" target=
230 "_top">Javascript</a> and thus <span class=
231 "QUOTE">"fragile"</span>. So if <span class="emphasis"><i class=
232 "EMPHASIS">still</i></span> a problem, we have an <a href=
233 "../user-manual/actions-file.html#ALIASES" target="_top">alias</a>
234 just for such sticky situations:
238 <table border="0" bgcolor="#E0E0E0" width="100%">
242 # Gmail is a _fragile_ site:
244 { <tt class="LITERAL">fragile</tt> }
253 Be sure to flush your browser's caches whenever making these kinds
254 of changes, just to make sure the changes <span class=
255 "QUOTE">"take"</span>.
258 Make sure the domain, host and path are appropriate as well. Your
259 browser can tell you where you are specifically and you should use
260 that information for your configuration settings. Note that above
261 it is not referenced as <tt class="LITERAL">gmail.com</tt>, which
262 is a valid domain name.
267 <a name="CONFIGFILES">3.9. What's the difference between the <span
268 class="QUOTE">"Cautious"</span>, <span class=
269 "QUOTE">"Medium"</span> and <span class="QUOTE">"Advanced"</span>
273 Configuring <span class="APPLICATION">Privoxy</span> is not
274 entirely trivial. To help you get started, we provide you with
275 three different default action <span class=
276 "QUOTE">"profiles"</span> in the web based actions file editor at
277 <a href="http://config.privoxy.org/show-status" target=
278 "_top">http://config.privoxy.org/show-status</a>. See the <a href=
279 "../user-manual/actions-file.html" target="_top"><i class=
280 "CITETITLE">User Manual</i></a> for a list of actions, and how the
281 default profiles are set.
284 Where the defaults are likely to break some sites, exceptions for
285 known popular <span class="QUOTE">"problem"</span> sites are
286 included, but in general, the more aggressive your default settings
287 are, the more exceptions you will have to make later. New users are
288 best to start off in <span class="QUOTE">"Cautious"</span> setting.
289 This is safest and will have the fewest problems. See the <a href=
290 "../user-manual/index.html" target="_top"><i class="CITETITLE">User
291 Manual</i></a> for a more detailed discussion.
294 It should be noted that the <span class="QUOTE">"Advanced"</span>
295 profile (formerly known as the <span class=
296 "QUOTE">"Adventuresome"</span> profile) is more aggressive, and
297 will make use of some of <span class="APPLICATION">Privoxy's</span>
298 advanced features. Use at your own risk!
303 <a name="BROWSECONFIG">3.10. Why can I change the configuration
304 with a browser? Does that not raise security issues?</a>
307 It may seem strange that regular users can edit the config files
308 with their browsers, although the whole <tt class=
309 "FILENAME">/etc/privoxy</tt> hierarchy belongs to the user <span
310 class="QUOTE">"privoxy"</span>, with only 644 permissions.
313 When you use the browser-based editor, <span class=
314 "APPLICATION">Privoxy</span> itself is writing to the config files.
315 Because <span class="APPLICATION">Privoxy</span> is running as the
316 user <span class="QUOTE">"privoxy"</span>, it can update its own
320 If you run <span class="APPLICATION">Privoxy</span> for multiple
321 untrusted users (e.g. in a LAN) or aren't entirely in control of
322 your own browser, you will probably want to make sure that the
323 web-based editor and remote toggle features are <span class=
324 "QUOTE">"off"</span> by setting <span class="QUOTE">"<tt class=
325 "LITERAL"><a href="../user-manual/config.html#ENABLE-EDIT-ACTIONS"
326 target="_top">enable-edit-actions</a> 0</tt>"</span> and <span
327 class="QUOTE">"<tt class="LITERAL"><a href=
328 "../user-manual/config.html#ENABLE-REMOTE-TOGGLE" target=
329 "_top">enable-remote-toggle</a> 0</tt>"</span> in the <a href=
330 "../user-manual/config.html" target="_top">main configuration
334 As of <span class="APPLICATION">Privoxy</span> 3.0.7 these options
335 are disabled by default.
340 <a name="AEN480">3.11. What is the <tt class=
341 "FILENAME">default.filter</tt> file? What is a <span class=
342 "QUOTE">"filter"</span>?</a>
345 The <a href="../user-manual/filter-file.html" target="_top"><tt
346 class="FILENAME">default.filter</tt></a> file is where <span class=
347 "emphasis"><i class="EMPHASIS">filters</i></span> as supplied by
348 the developers are defined. Filters are a special subset of actions
349 that can be used to modify or remove web page content or headers on
350 the fly. Content filters can be applied to <span class=
351 "emphasis"><i class="EMPHASIS">anything</i></span> in the page
352 source, header filters can be applied to either server or client
353 headers. Regular expressions are used to accomplish this.
356 There are a number of pre-defined filters to deal with common
357 annoyances. The filters are only defined here, to invoke them, you
358 need to use the <a href="../user-manual/actions-file.html#FILTER"
359 target="_top"><tt class="LITERAL">filter</tt> action</a> in one of
360 the actions files. Content filtering is automatically disabled for
361 inappropriate MIME types, but if you know better than Privoxy what
362 should or should not be filtered you can filter any content you
366 Filters should <span class="emphasis"><i class=
367 "EMPHASIS">not</i></span> be confused with <a href=
368 "../user-manual/actions-file.html#BLOCK" target="_top"><tt class=
369 "LITERAL">blocks</tt></a>, which is a completely different action,
370 and is more typically used to block ads and unwanted sites.
373 If you are familiar with regular expressions, and HTML, you can
374 look at the provided <tt class="FILENAME">default.filter</tt> with
375 a text editor and define your own filters. This is potentially a
376 very powerful feature, but requires some expertise in both regular
377 expressions and HTML/HTTP. You should place any modifications to
378 the default filters, or any new ones you create in a separate file,
379 such as <tt class="FILENAME">user.filter</tt>, so they won't be
380 overwritten during upgrades. The ability to define multiple filter
381 files in <tt class="FILENAME">config</tt> is a new feature as of v.
385 There is no GUI editor option for this part of the configuration,
386 but you can disable/enable the various pre-defined filters of the
387 included <tt class="FILENAME">default.filter</tt> file with the <a
388 href="http://config.privoxy.org/show-status" target=
389 "_top">web-based actions file editor</a>. Note that the custom
390 actions editor must be explicitly enabled in the main config file
391 (see <a href="../user-manual/config.html#ENABLE-EDIT-ACTIONS"
392 target="_top">enable-edit-actions</a>).
395 If you intend to develop your own filters, you might want to have a
396 look at <a href="http://www.fabiankeil.de/sourcecode/pft/" target=
397 "_top">Privoxy-Filter-Test</a>.
402 <a name="LANCONFIG">3.12. How can I set up Privoxy to act as a
403 proxy for my LAN?</a>
406 By default, <span class="APPLICATION">Privoxy</span> only responds
407 to requests from <tt class="LITERAL">127.0.0.1</tt> (localhost). To
408 have it act as a server for a network, this needs to be changed in
409 the <a href="../user-manual/config.html" target="_top">main
410 configuration file</a>. Look for the <tt class="LITERAL"><a href=
411 "../user-manual/config.html#LISTEN-ADDRESS" target=
412 "_top">listen-address</a></tt> option, which may be commented out
413 with a <span class="QUOTE">"#"</span> symbol. Make sure it is
414 uncommented, and assign it the address of the LAN gateway
415 interface, and port number to use. Assuming your LAN address is
416 192.168.1.1 and you wish to run <span class=
417 "APPLICATION">Privoxy</span> on port 8118, this line should look
422 <table border="0" bgcolor="#E0E0E0" width="100%">
426 listen-address 192.168.1.1:8118
433 Save the file, and restart <span class=
434 "APPLICATION">Privoxy</span>. Configure all browsers on the network
435 then to use this address and port number.
438 Alternately, you can have <span class="APPLICATION">Privoxy</span>
439 listen on all available interfaces:
443 <table border="0" bgcolor="#E0E0E0" width="100%">
454 And then use <span class="APPLICATION">Privoxy's</span> <a href=
455 "../user-manual/config.html#PERMIT-ACCESS" target=
456 "_top">permit-access</a> feature to limit connections. A firewall
457 in this situation is recommended as well.
460 The above steps should be the same for any TCP network, regardless
464 If you run <span class="APPLICATION">Privoxy</span> on a LAN with
465 untrusted users, we recommend that you double-check the <a href=
466 "../user-manual/config.html#ACCESS-CONTROL" target="_top">access
467 control and security</a> options!
472 <a name="AEN531">3.13. Instead of ads, now I get a checkerboard
473 pattern. I don't want to see anything.</a>
476 The replacement for blocked images can be controlled with the <a
477 href="../user-manual/actions-file.html#SET-IMAGE-BLOCKER" target=
478 "_top"><tt class="LITERAL">set-image-blocker</tt> action</a>. You
479 have the choice of a checkerboard pattern, a transparent 1x1 GIF
480 image (aka <span class="QUOTE">"blank"</span>), or a redirect to a
481 custom image of your choice. Note that this choice only has effect
482 for images which are blocked as images, i.e. whose URLs match both
483 a <tt class="LITERAL"><a href=
484 "../user-manual/actions-file.html#HANDLE-AS-IMAGE" target=
485 "_top">handle-as-image</a></tt> <span class="emphasis"><i class=
486 "EMPHASIS">and</i></span> <tt class="LITERAL"><a href=
487 "../user-manual/actions-file.html#BLOCK" target=
488 "_top">block</a></tt> action.
491 If you want to see nothing, then change the <a href=
492 "../user-manual/actions-file.html#SET-IMAGE-BLOCKER" target=
493 "_top"><tt class="LITERAL">set-image-blocker</tt> action</a> to
494 <span class="QUOTE">"blank"</span>. This can be done by editing the
495 <tt class="FILENAME">user.action</tt> file, or through the <a href=
496 "http://config.privoxy.org/show-status" target="_top">web-based
497 actions file editor</a>.
502 <a name="AEN548">3.14. Why would anybody want to see a checkerboard
506 Remember that <a href="general.html#WHATSANAD">telling which image
507 is an ad and which isn't</a>, is an educated guess. While we hope
508 that the standard configuration is rather smart, it will make
509 occasional mistakes. The checkerboard image is visually decent, and
510 it shows you where images have been blocked, which can be very
511 helpful in case some navigation aid or otherwise innocent image was
512 erroneously blocked. It is recommended for new users so they can
513 <span class="QUOTE">"see"</span> what is happening. Some people
514 might also enjoy seeing how many banners they <span class=
515 "emphasis"><i class="EMPHASIS">don't</i></span> have to see.
520 <a name="AEN554">3.15. I see some images being replaced with text
521 instead of the checkerboard image. Why and how do I get rid of
525 This happens when the banners are not embedded in the HTML code of
526 the page itself, but in separate HTML (sub)documents that are
527 loaded into (i)frames or (i)layers, and these external HTML
528 documents are blocked. Being non-images they get replaced by a
529 substitute HTML page rather than a substitute image, which wouldn't
530 work out technically, since the browser expects and accepts only
531 HTML when it has requested an HTML document.
534 The substitute page adapts to the available space and shows itself
535 as a miniature two-liner if loaded into small frames, or full-blown
536 with a large red "BLOCKED" banner if space allows.
539 If you prefer the banners to be blocked by images, you must see to
540 it that the HTML documents in which they are embedded are not
541 blocked. Clicking the <span class="QUOTE">"See why"</span> link
542 offered in the substitute page will show you which rule blocked the
543 page. After changing the rule and un-blocking the HTML documents,
544 the browser will try to load the actual banner images and the usual
545 image blocking will (hopefully!) kick in.
550 <a name="SRVANY">3.16. Can Privoxy run as a service on
554 Yes. Version 3.0.5 introduces full <span class=
555 "APPLICATION">Windows</span> service functionality. See <a href=
556 "../user-manual/installation.html#installation-pack-win" target=
557 "_top">the <i class="CITETITLE">User Manual</i></a> for details on
558 how to install and configure <span class=
559 "APPLICATION">Privoxy</span> as a service.
562 Earlier 3.x versions could run as a system service using <b class=
563 "COMMAND">srvany.exe</b>. See the discussion at <a href=
564 "http://sourceforge.net/tracker/?func=detail&atid=361118&aid=485617&group_id=11118"
566 "_top">http://sourceforge.net/tracker/?func=detail&atid=361118&aid=485617&group_id=11118</a>,
567 for details, and a sample configuration.
572 <a name="OTHERPROXY">3.17. How can I make Privoxy work with other
576 This can be done and is often useful to combine the benefits of
577 <span class="APPLICATION">Privoxy</span> with those of a another
578 proxy, for example to cache content. See the <a href=
579 "../user-manual/config.html#FORWARDING" target="_top">forwarding
580 chapter</a> in the <a href="../user-manual/index.html" target=
581 "_top">User Manual</a> which describes how to do this. If you
582 intend to use Privoxy with Tor, please also have a look at <a href=
583 "misc.html#TOR">How do I use Privoxy together with Tor</a>.
588 <a name="PORT-80">3.18. Can I just set Privoxy to use port 80 and
589 thus avoid individual browser configuration?</a>
592 No, its more complicated than that. This only works with special
593 kinds of proxies known as <span class="QUOTE">"intercepting"</span>
594 proxies (<a href="configuration.html#INTERCEPTING">see below</a>).
599 <a name="TRANSPARENT">3.19. Can Privoxy run as a <span class=
600 "QUOTE">"transparent"</span> proxy?</a>
603 The whole idea of Privoxy is to modify client requests and server
604 responses in all sorts of ways and therefore it's not a transparent
605 proxy as described in <a href="http://tools.ietf.org/html/rfc2616"
606 target="_top">RFC 2616</a>.
609 However, some people say <span class="QUOTE">"transparent
610 proxy"</span> when they mean <span class="QUOTE">"intercepting
611 proxy"</span>. If you are one of them, please read the <a href=
612 "configuration.html#INTERCEPTING">next entry</a>.
617 <a name="INTERCEPTING">3.20. Can Privoxy run as a <span class=
618 "QUOTE">"intercepting"</span> proxy?</a>
621 <span class="APPLICATION">Privoxy</span> can't intercept traffic
622 itself, but it can handle requests that where intercepted and
623 redirected with a packet filter (like <span class=
624 "APPLICATION">PF</span> or <span class=
625 "APPLICATION">iptables</span>), as long as the <tt class=
626 "LITERAL">Host</tt> header is present.
629 As the <tt class="LITERAL">Host</tt> header is required by HTTP/1.1
630 and as most web sites rely on it anyway, this limitation shouldn't
634 Please refer to your packet filter's documentation to learn how to
635 intercept and redirect traffic into <span class=
636 "APPLICATION">Privoxy</span>. Afterward you just have to configure
637 <span class="APPLICATION">Privoxy</span> to <a href=
638 "../user-manual/config.html#ACCEPT-INTERCEPTED-REQUESTS" target=
639 "_top">accept intercepted requests</a>.
644 <a name="OUTLOOK">3.21. How can I configure Privoxy for use with
648 Versions of <span class="APPLICATION">Outlook</span> prior to
649 Office 2007, use <span class="APPLICATION">Internet Explorer</span>
650 components to both render HTML, and fetch any HTTP requests that
651 may be embedded in an HTML email. So however you have <span class=
652 "APPLICATION">Privoxy</span> configured to work with IE, this
653 configuration should automatically be shared, at least with older
654 version of Internet Explorer.
657 Starting with Office 2007, Microsoft is instead using the MS-Word
658 rendering engine with Outlook. It is unknown whether this can be
659 configured to use a proxy.
664 <a name="OUTLOOK-MORE">3.22. How can I have separate rules just for
668 The short answer is, you can't. <span class=
669 "APPLICATION">Privoxy</span> has no way of knowing which particular
670 application makes a request, so there is no way to distinguish
671 between web pages and HTML mail. <span class=
672 "APPLICATION">Privoxy</span> just blindly proxies all requests. In
673 the case of <span class="APPLICATION">Outlook Express</span> (see
674 above), OE uses IE anyway, and there is no way for <span class=
675 "APPLICATION">Privoxy</span> to ever be able to distinguish between
676 them (nor could any other proxy type application for that matter).
679 For a good discussion of some of the issues involved (including
680 privacy and security issues), see <a href=
681 "http://sourceforge.net/tracker/?func=detail&atid=211118&aid=629518&group_id=11118"
683 "_top">http://sourceforge.net/tracker/?func=detail&atid=211118&aid=629518&group_id=11118</a>.
688 <a name="SNEAKY-COOKIES">3.23. I sometimes notice cookies sneaking
692 <a href="http://en.wikipedia.org/wiki/Browser_cookie" target=
693 "_top">Cookies</a> can be set in several ways. The classic method
694 is via the <tt class="LITERAL">Set-Cookie</tt> HTTP header. This is
695 straightforward, and an easy one to manipulate, such as the <span
696 class="APPLICATION">Privoxy</span> concept of <a href=
697 "../user-manual/actions-file.html#SESSION-COOKIES-ONLY" target=
698 "_top">session-cookies-only</a>. There is also the possibility of
699 using <a href="http://en.wikipedia.org/wiki/Javascript" target=
700 "_top">Javascript</a> to set cookies (<span class=
701 "APPLICATION">Privoxy</span> calls these <tt class=
702 "LITERAL">content-cookies</tt>). This is trickier because the
703 syntax can vary widely, and thus requires a certain amount of
704 guesswork. It is not realistic to catch all of these short of
705 disabling Javascript, which would break many sites. And lastly, if
706 the cookies are embedded in a HTTPS/SSL secure session via
707 Javascript, they are beyond <span class=
708 "APPLICATION">Privoxy's</span> reach.
711 All in all, <span class="APPLICATION">Privoxy</span> can help
712 manage cookies in general, can help minimize the loss of privacy
713 posed by cookies, but can't realistically stop all cookies.
718 <a name="EVIL-COOKIES">3.24. Are all cookies bad? Why?</a>
721 No, in fact there are many beneficial uses of <a href=
722 "http://en.wikipedia.org/wiki/Browser_cookie" target=
723 "_top">cookies</a>. Cookies are just a method that browsers can use
724 to store data between pages, or between browser sessions. Sometimes
725 there is a good reason for this, and the user's life is a bit
726 easier as a result. But there is a long history of some websites
727 taking advantage of this layer of trust, and using the data they
728 glean from you and your browsing habits for their own purposes, and
729 maybe to your potential detriment. Such sites are using you and
730 storing their data on your system. That is why the privacy
731 conscious watch from whom those cookies come, and why they really
732 <span class="emphasis"><i class="EMPHASIS">need</i></span> to be
736 See the <a href="http://en.wikipedia.org/wiki/Browser_cookie"
737 target="_top">Wikipedia cookie definition</a> for more.
742 <a name="ALLOW-COOKIES">3.25. How can I allow permanent cookies for
743 my trusted sites?</a>
746 There are several actions that relate to cookies. The default
747 behavior is to allow only <span class="QUOTE">"session
748 cookies"</span>, which means the cookies only last for the current
749 browser session. This eliminates most kinds of abuse related to
750 cookies. But there may be cases where you want cookies to last.
753 To disable all cookie actions, so that cookies are allowed
754 unrestricted, both in and out, for <tt class=
755 "LITERAL">example.com</tt>:
759 <table border="0" bgcolor="#E0E0E0" width="100%">
763 { -crunch-incoming-cookies -crunch-outgoing-cookies -session-cookies-only -filter{content-cookies} }
771 Place the above in <tt class="FILENAME">user.action</tt>. Note that
772 some of these may be off by default anyway, so this might be
773 redundant, but there is no harm being explicit in what you want to
774 happen. <tt class="FILENAME">user.action</tt> includes an alias for
775 this situation, called <tt class="LITERAL">allow-all-cookies</tt>.
780 <a name="MULTIPLES">3.26. Can I have separate configurations for
784 Each instance of <span class="APPLICATION">Privoxy</span> has its
785 own configuration, including such attributes as the TCP port that
786 it listens on. What you can do is run multiple instances of <span
787 class="APPLICATION">Privoxy</span>, each with a unique <a href=
788 "../user-manual/config.html#LISTEN-ADDRESS" target=
789 "_top">listen-address</a> configuration setting, and configuration
790 path, and then each of these can have their own configurations.
791 Think of it as per-port configuration.
794 Simple enough for a few users, but for large installations,
795 consider having groups of users that might share like
801 <a name="WHITELISTS">3.27. Can I set-up Privoxy as a whitelist of
802 <span class="QUOTE">"good"</span> sites?</a>
805 Sure. There are a couple of things you can do for simple
806 white-listing. Here's one real easy one:
808 <table border="0" bgcolor="#E0E0E0" width="100%">
812 ############################################################
814 ############################################################
815 { <a href="../user-manual/actions-file.html#BLOCK" target=
819 ############################################################
821 ############################################################
822 { <a href="../user-manual/actions-file.html#BLOCK" target=
832 This allows access to only those three sites by first blocking all
833 URLs, and then subsequently allowing three specific exceptions.
836 Another approach is <span class="APPLICATION">Privoxy's</span> <tt
837 class="LITERAL">trustfile</tt> concept, which incorporates the
838 notion of <span class="QUOTE">"trusted referrers"</span>. See the
839 <a href="../user-manual/config.html#TRUSTFILE" target="_top">Trust
840 documentation</a> for details.
843 These are fairly simple approaches and are not completely
844 foolproof. There are various other configuration options that
845 should be disabled (described elsewhere here and in <a href=
846 "../user-manual/" target="_top">the User Manual</a>) so that users
847 can't modify their own configuration and easily circumvent the
853 <a name="NO-ADBLOCK">3.28. How can I turn off ad-blocking?</a>
856 Ad blocking is achieved through a complex application of various
857 <span class="APPLICATION">Privoxy</span> <a href=
858 "../user-manual/actions-file.html" target="_top">actions</a>. These
859 actions are deployed against simple images, banners, flash
860 animations, text pages, JavaScript, pop-ups and pop-unders, etc.,
861 so its not as simple as just turning one or two actions off. The
862 various actions that make up <span class=
863 "APPLICATION">Privoxy</span> ad blocking are hard-coded into the
864 default configuration files. It has been assumed that everyone
865 using <span class="APPLICATION">Privoxy</span> is interested in
866 this particular feature.
869 If you want to do without this, there are several approaches you
870 can take: You can manually undo the many block rules in <tt class=
871 "FILENAME">default.action</tt>. Or even easier, just create your
872 own <tt class="FILENAME">default.action</tt> file from scratch
873 without the many ad blocking rules, and corresponding exceptions.
874 Or lastly, if you are not concerned about the additional blocks
875 that are done for privacy reasons, you can very easily over-ride
876 <span class="emphasis"><i class="EMPHASIS">all</i></span> blocking
877 with the following very simple rule in your <tt class=
878 "FILENAME">user.action</tt>:
882 <table border="0" bgcolor="#E0E0E0" width="100%">
886 # Unblock everybody, everywhere
887 { <a href="../user-manual/actions-file.html#BLOCK" target=
889 / # UN-Block *all* URLs
896 Or even a more comprehensive reversing of various ad related
901 <table border="0" bgcolor="#E0E0E0" width="100%">
905 # Unblock everybody, everywhere, and turn off appropriate filtering, etc
906 { <a href="../user-manual/actions-file.html#BLOCK" target=
908 <a href="../user-manual/actions-file.html#FILTER-BANNERS-BY-SIZE" target=
909 "_top">-filter{banners-by-size}</a> \
910 <a href="../user-manual/actions-file.html#FILTER-BANNERS-BY-LINK" target=
911 "_top">-filter{banners-by-link}</a> \
912 <tt class="LITERAL">allow-popups</tt> \
914 / # UN-Block *all* URLs and allow ads
921 This last <span class="QUOTE">"action"</span> in this compound
922 statement, <tt class="LITERAL">allow-popups</tt>, is an <a href=
923 "../user-manual/actions-file.html#ALIASES" target="_top">alias</a>
924 that disables various pop-up blocking features.
929 <a name="TEMPLATES">3.29. How can I have custom template pages,
930 like the <span class="emphasis"><i class=
931 "EMPHASIS">BLOCKED</i></span> page?</a>
934 <span class="APPLICATION">Privoxy</span> <span class=
935 "QUOTE">"templates"</span> are specialized text files utilized by
936 <span class="APPLICATION">Privoxy</span> for various purposes and
937 can easily be modified using any text editor. All the template
938 pages are installed in a sub-directory appropriately named: <tt
939 class="FILENAME">templates</tt>. Knowing something about HTML
940 syntax will of course be helpful.
943 Be forewarned that the default templates are subject to being
944 overwritten during upgrades. You can, however, create completely
945 new templates, place them in another directory and specify the
946 alternate path in the main <tt class="FILENAME">config</tt>. For
947 details, have a look at the <a href=
948 "../user-manual/config.html#templdir" target="_top">templdir</a>
954 <a name="BLOCKALL">3.30. How can I remove the <span class=
955 "QUOTE">"Go There Anyway"</span> link from the <span class=
956 "emphasis"><i class="EMPHASIS">BLOCKED</i></span> page?</a>
959 There is more than one way to do it (although Perl is not
963 Editing the BLOCKED template page (see above) may dissuade some
964 users, but this method is easily circumvented. Where you need this
965 level of control, you might want to build <span class=
966 "APPLICATION">Privoxy</span> from source, and disable various
967 features that are available as compile-time options. You should <b
968 class="COMMAND">configure</b> the sources as follows:
972 <table border="0" bgcolor="#E0E0E0" width="100%">
976 ./configure --disable-toggle --disable-editor --disable-force
983 This will create an executable with hard-coded security features so
984 that <span class="APPLICATION">Privoxy</span> does not allow easy
985 bypassing of blocked sites, or changing the current configuration
986 via any connected user's web browser.
989 Finally, all of these features can also be toggled on/off via
990 options in <span class="APPLICATION">Privoxy's</span> main <a href=
991 "../user-manual/config.html#ACCESS-CONTROL" target=
992 "_top">config</a> file which means you don't have to recompile
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