X-Git-Url: http://www.privoxy.org/gitweb/?p=privoxy.git;a=blobdiff_plain;f=doc%2Fsource%2Ffaq.sgml;h=e32b52df8809af25e431243f603c13de2897e060;hp=9c39a814ac03a271f8d3f0735efaeb27c815464e;hb=15715ba3aeaa90fd30b64d5951d427fcf88db6a8;hpb=6e572effc9ebba707db8b8f2c3fde9c4bcb72dc7 diff --git a/doc/source/faq.sgml b/doc/source/faq.sgml index 9c39a814..e32b52df 100644 --- a/doc/source/faq.sgml +++ b/doc/source/faq.sgml @@ -1,4 +1,22 @@ - + + + + + + + + + + + + + + + + + +]> -
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Privoxy Frequently Asked Questions -$Id: faq.sgml,v 1.28 2002/03/25 04:27:33 hal9 Exp $ + + + + + Copyright &my-copy; 2001, 2002 by + Privoxy Developers + + + +$Id: faq.sgml,v 1.60 2002/05/22 17:17:48 oes Exp $ + + + + + + This is here to keep vim syntax file from breaking :/ + If I knew enough to fix it, I would. + PLEASE DO NOT REMOVE! HB: hal@foobox.net + + +]]> -The FAQ document gives users and developers alike answers to frequently asked -questions about -Privoxy. Privoxy is a web -proxy with advanced filtering capabilities for protecting privacy, filtering -web page content, managing cookies, controlling access, and removing ads, -banners, pop-ups and other obnoxious Internet -Junk. Privoxy has a very flexible configuration and -can be customized to suit individual needs and -tastes. Privoxy has application for both stand-alone -systems and multi-user networks. + This FAQ gives quick answers to frequently asked questions about + Privoxy + . It can't and doesn't replace the + user manual. + + + &p-intro; + + -You can find the latest version of the document at http://ijbswa.sourceforge.net/faq/. -Please see the Contact section in the -user-manual if you want to contact the developers. + You can find the latest version of the document at http://www.privoxy.org/faq/. + Please see the Contact section if you want to contact the developers. @@ -58,211 +136,153 @@ Please see the Contact section in the - - +General Information -Frequently Asked Questions +What is this new version of <application>Privoxy</application>? - - -General Information + + &history; + -What is this new version of <application>Privoxy</application>? - - The original Internet Junkbuster (tm) is a - copyrighted product of Junkbusters - Corporation. Development of this effort stopped some time ago as of - version 2.0.2. Stefan Waldherr started the ijbswa project on Sourceforge to rekindle - development. Other developers subsequently joined with Stefan, and have - since added many new features, refinements and enhancements. - - - The new Privoxy started with the same - code base, but has changed significantly at this point. - - - + - + Why <quote>Privoxy</quote>? Why a name change at all? - Privoxy is for Privacy Enhancing Proxy. - There are possible legal complications from the continued use of the - Junkbuster name, which is a trademark of - The Junkbusters Corporation. - There are no objections from Junkbusters Corporation to the project - itself though. + Privoxy is the + Privacy Enhancing Proxy. Also, its content + modification and junk suppression allow you to browse your + private edition of the web. - - The developers also believed that there so many changes from the original + Junkbusters Corporation + continues to offer their original version of the Internet + Junkbuster, so publishing our + Junkbuster-derived software under the same name + led to confusion. + + + There are also potential legal complications from the continued use of the + Junkbuster name, which is a registered trademark of + Junkbusters Corporation. + There are, however, no objections from Junkbusters Corporation to the + Privoxy project itself, and they, in fact, still + share our ideals and goals. + + + The developers also believed that there are so many changes from the original code, that it was time to make a clean break from the past and make - a name in their own right. + a name in their own right. - + -How does it differ from the old <application>Junkbuster?</application> - - All the old features remain. The new Privoxy - still blocks ads and banners, still manages cookies, and still helps protect - your privacy. But, these are all enhanced, and many new features have been - added, all in the same vein. +How does <application>Privoxy</application> differ +from the old <application>Junkbuster?</application> + + Privoxy picks up where + Junkbuster left off. All the old features remain. + The new Privoxy still blocks ads and banners, + still manages cookies, and still helps protect your privacy. But, these are + all enhanced, and many new features have been added, all in the same vein. - The configuration has changed significantly as well. This is something that - users will notice right off the bat. The blocklist file does - not exist any more. This is replaced by actions files, such - as default.actions. This is where most of the per site - configuration is now. - - - - -What are some of the new features? - + The configuration has changed significantly as well. This is something that + users will notice right off the bat if upgrading from + Junkbuster 2.0.x. The blocklist + cookielist, imagelist and much more has been + combined into the actions files, with a completely different + syntax. See the note to + upgraders for details. + - - - - - Integrated browser based configuration and control utility (http://p.p). Browser-based tracing of rule - and filter effects. - - - - - - Blocking of annoying pop-up browser windows. - - - - - - HTTP/1.1 compliant (most, but not all 1.1 features are supported). - - - - - - Support for Perl Compatible Regular Expressions in the configuration files, and - generally a more sophisticated and flexible configuration syntax over - previous versions. - - - - - - GIF de-animation. - - - - - - Web page content filtering (removes banners based on size, - invisible web-bugs, JavaScript, pop-ups, status bar abuse, - etc.) - - - - - - Bypass many click-tracking scripts (avoids script redirection). - - - - - - - Multi-threaded (POSIX and native threads). - - - - - - Auto-detection and re-reading of config file changes. - - - - - - User-customizable HTML templates (e.g. 404 error page). - - - - - - Improved cookie management features (e.g. session based cookies). - - - - - - Builds from source on most UNIX-like systems. Packages available for: Linux - (RedHat, SuSE, or Debian), Windows, Sun Solaris, Mac OSX, OS/2, HP-UX 11 and AmigaOS. - - - - - - - In addition, the configuration is much more powerful and versatile over-all. - - - - + Privoxy's new features include: - + + &newfeatures; + -What is a <quote>proxy</quote>? How does +</sect2> + +<sect2 renderas="sect3" id="proxymoron"><title>What is a <quote>proxy</quote>? How does <application>Privoxy</application> work? - When you connect to a web site with Privoxy, - you are really connecting to your locally running version of - Privoxy. Privoxy - intercepts your requests for the web page, and relays that to the - real web site. The web site sends the HTTP data stream - back to Privoxy, where - Privoxy can work its magic before it - relays this data back to your web browser. + A web proxy is a service, based on a software such as Privoxy, + that clients (i.e. browsers) can use instead of connecting directly to the web + servers on the Internet. The clients then ask the proxy to fetch the objects + they need (web pages, images, movies etc) on their behalf, and when the proxy + has done so, it hands the results back to the client. - - Since Privoxy sits between you and the - WWW, it is in a position to intercept and completely manage all web traffic and - HTTP content before it gets to your browser. - Privoxy uses various programming methods to do - this, all of which is under your control via the various configuration - files and options. + There are many reasons to use web proxies, such as security (firewalling), + efficiency (caching) and others, and there are just as many different proxies + to accommodate those needs. - - There are many kinds of proxies. Privoxy best - fits the filtering proxy category. + Privoxy is a proxy that is solely focused on privacy + protection and junk elimination. Sitting between your browser(s) and the Internet, + it is in a perfect position to filter outbound personal information that your + browser is leaking, as well as inbound junk. It uses a variety of techniques to do + this, all of which are under your control via the various configuration + files and options. + - -My browser does the same things as +<sect2 renderas="sect3" id="whatsanad"> +<title id="knows">How does <application>Privoxy</application> know what is +an ad, and what is not? + + Privoxy's approach to blocking ads is twofold: + + + First, there are certain patterns in the locations (URLs) + of banner images. This applies to both the path (you wouldn't guess how many + web sites serve their banners from a directory called banners!) + and the host (blocking the big banner hosting services like doublecklick.net + already helps a lot). Privoxy takes advantage of this + fact by using URL + patterns to sort out and block the requests for banners. + + + Second, banners tend to come in certain sizes. But you + can't tell the size of an image by its URL without downloading it, and if you + do, it's too late to save bandwidth. Therefore, Privoxy + also inspects the HTML sources of web pages while they are loaded, and replaces + references to images with standard banner sizes by dummy references, so that + your browser doesn't request them anymore in the first place. + + + Both of this involves a certain amount of guesswork and is, of course, freely + configurable. + + + + +Can <application>Privoxy</application> make mistakes? +This does not sound very scientific. + + Actually, it's a black art ;-) And yes, it is always possible to have a broad + rule accidentally block or change something by mistake. There is a good chance + you may run into such a situation at some point. It is tricky writing rules to + cover every conceivable possibility, and not occasionally get false positives. + + + + But this should not be a big concern since the + Privoxy configuration is very flexible, and + includes tools to help identify these types of situations so they can be + addressed as needed, allowing you to customize your installation. + (See the Troubleshooting section below.) + + + + + +My browser does the same things as <application>Privoxy</application>. Why should I use <application>Privoxy</application> at all? @@ -276,81 +296,116 @@ Please see the Contact section in the have a LAN with multiple computers. This way all the configuration is in one place, and you don't have to maintain a similar configuration for possibly many browsers. - - + -Is there is a license or fee? What about a +<sect2 renderas="sect3" id="license"><title>Is there is a license or fee? What about a warranty? Registration? - Privoxy is licensed under the - GNU General Public License (GPL). It is free to use, copy, - modify or distribute as you wish under the terms of this license. - See http://www.gnu.org/copyleft/gpl.html - for specifics. - + Privoxy is licensed under the GNU General Public License (GPL). + It is free to use, copy, modify or distribute as you wish under the terms of this + license. Please see the Copyright section for more + information on the license and copyright. Or the LICENSE file + that should be included. + - There is no warranty of any kind, expressed, implied or otherwise. That is - something that would cost real money ;-) There is no registration either. + There is no warranty of any kind, expressed, implied or otherwise. + That is something that would cost real money ;-) There is no registration either. Privoxy really is free in every respect! - - -I would like to help you, what do I do? + + +I would like to help you, what do I do? -Money Money Money +Money Money Money - We, of course, welcome donations and use the money for domain registering, - regular world-wide get-togethers (hahaha). Anyway, we'll soon describe the - process how to donate money to the team. + We, of course, welcome donations and could use money for domain registering, + buying software to test Privoxy with, and, of course, + for regular world-wide get-togethers (hahaha). If you enjoy the software and feel + like helping us with a donation, just drop us a note. - + -You want to work with us? +Software + + If you are a vendor of a web-related software like a browser, web server + or proxy, and would like us to ensure that Privoxy + runs smoothly with your product, you might consider supplying us with a + copy or license. We can't, however, guarantee that we will fix all potential + compatibility issues as a result. + + + +You want to work with us? Well, helping the team is always a good idea. We welcome new developers, - RPM gurus or documentation makers. Simply get an account on sourceforge.net - and mail your id to the developer mailing list. Then read the - section Quickstart in the developers manual. + packaging gurus or documentation writers. Simply get an account on SourceForge.net + and mail your id to the developers + mailing list. Then read the Developer's Manual. -Once we have added you to the team, you'll have write access to the CVS -repository, and together we'll find a suitable task for you. + Once we have added you to the team, you'll have write access to the CVS repository, and + together we'll find a suitable task for you. - - + + -Installation +Installation + + +Which browsers are supported by <application>Privoxy</application>? + + Any browser that can be configured to use a proxy, which + should be virtually all browsers. Direct browser support is not necessary + since Privoxy runs as a separate application and + talks to the browser in the standardized HTTP protocol, just like a web server + does. + + + + +Which operating systems are supported? + +&supported; + -Can I install the new - <application>Privoxy</application> over the old one? +Can I install + <application>Privoxy</application> over <application>Junkbuster</application>? - We recommend you uninstall the old Junkbuster + We recommend you un-install Junkbuster first to minimize conflicts and confusion. You may want to save your old configuration files for future reference. The configuration - is substantially changed. + files and syntax have substantially changed, so you will need to manually + port your old patterns. See the note + to upgraders and installation + chapter in the user manual + for details. - See the user-manual for - platform specific installation instructions. [FIXME: This is meant for after - the name change for 3.0!] + Note: Some installers may automatically un-install + Junkbuster, if present! - - - + + + I just installed <application>Privoxy</application>. Is there anything special I have to do now? @@ -358,44 +413,49 @@ special I have to do now? All browsers must be told to use Privoxy as a proxy by specifying the correct proxy address and port number in the appropriate configuration area for the browser. See below. + You should also flush your browser's memory and disk cache to get rid of any + cached junk items. - + -What is the proxy address of <application>Privoxy</application>? +What is the proxy address of <application>Privoxy</application>? If you set up the Privoxy to run on the computer you browse from (rather than your ISP's server or some - networked computer on a LAN), the proxy will be on localhost - (which is the special name used by every computer on the Internet to refer - to itself) and the port will be 8118 (unless you have Privoxy to run on a different port with the - listen-address config option). + networked computer on a LAN), the proxy will be on 127.0.0.1 + (sometimes referred to as localhost, + which is the special name used by every computer on the Internet to refer + to itself) and the port will be 8118 (unless you have Privoxy + to run on a different port with the listen-address config option). When configuring your browser's proxy settings you typically enter - the word localhost in the boxes next to HTTP - and Secure (HTTPS) and then the number 8118 - for port. This tells your browser to send all web - requests to Privoxy instead of directly to the - Internet. + the word localhost or the IP address 127.0.0.1 + in the boxes next to HTTP and Secure (HTTPS) and + then the number 8118 for port. + This tells your browser to send all web requests to Privoxy + instead of directly to the Internet. Privoxy can also be used to proxy for a Local Area Network. In this case, your would enter either the IP address of the LAN host where Privoxy is running, or the equivalent hostname. Port assignment would be - same as above. + same as above. Note that Privoxy doesn't + listen on any LAN interfaces by default. Privoxy does not currently handle protocols such as FTP, SMTP, IM, IRC, ICQ, or other Internet protocols. - + - + I just installed <application>Privoxy</application>, and nothing is happening. All the ads are there. What's wrong? @@ -405,333 +465,347 @@ All the ads are there. What's wrong? the browser's caches to force a full re-reading of pages. You can verify that Privoxy is running, and your browser is correctly configured by entering the special URL: - http://p.p/. This should give you - a banner that says This is Privoxy and - access to Privoxy's internal configuration. - If you see this, then you are good to go. If not, the browser or - Privoxy are not set up correctly. + http://config.privoxy.org/. + This should take you to a page titled This is Privoxy.. with + access to Privoxy's internal configuration. + If you see this, then you are good to go. If you receive a page saying + Privoxy is not running, then the browser is not set up to use + your Privoxy installation. + If you receive anything else (probably nothing at all), it could either + be that the browser is not set up correctly, or that + Privoxy is not running at all. Check the log file. - - + + + -Configuration +Configuration -Can I use my old config files? +Can I use my old config files? - There are major changes to Junkbuster - configuration from version 2.0.x to 2.9.x and later. The older files will - not work at all. If this is the case, you will need to re-enter your old - data into the new configuration structure. This is probably also a good - recommendation even if upgrading from 2.9.x to 3.x since there were - many minor changes along the way. + The syntax, number, and purpose of configuration files has substantially + changed from Junkbuster and earlier versions + of Privoxy. The old files, like blocklist + will not work at all. If you are upgrading from a 2.0.x version, you will + need to port your configuration data to the new format. Note that even the + pattern syntax has changed! Even configuration files from the 2.9.x versions + will need to be adapted, as configuration syntax has been very much in flow + in the 2.9.x series. - + - + What is an <quote>actions</quote> file? - actions files are where various actions that - Privoxy might take, are configured. - Typically, you would define a set of default actions that apply - to all URLs, then add exceptions to these defaults. + Actions files + are where various actions + that Privoxy might take while processing a certain + request, are configured. Typically, you would define a set of default actions + that apply to all URLs, then add exceptions to these defaults where needed. - Actions can be defined on a per site basis, or for groups of sites. Actions - can also be grouped together and then applied to one or more sites. There - are many possible actions that might apply to any given site. As an example, - if we are blocking cookies as one of our default - actions, but need to accept cookies from a given - site, we would define this in our actions file. - + Actions can be defined on a URL pattern basis, i.e. + for single URLs, whole web sites, groups or parts thereof etc. Actions can also be + grouped together and then applied to requests matching one or more patterns. + There are many possible actions that might apply to any given site. As an example, + if you are blocking cookies as one of your default actions, but need to accept + cookies from a given site, you would need to define an exception for this + site in one of your actions files, preferably in user.action - - Privoxy comes with several default - actions files, with varying degrees - of filtering and blocking, as starting points for your own - configuration (see below). - - - + - -The <quote>actions</quote>concept confuses me. Please list +<sect2 renderas="sect3" id="actionss"> +<title>The <quote>actions</quote> concept confuses me. Please list some of these <quote>actions</quote>. - These are all explained in the - user-manual. - Please refer to that. + For a comprehensive discussion of the actions concept, please refer + to the actions file + chapter in the user + manual. It includes a list of all actions + and an actions + file tutorial to get you started. - + - + How are actions files configured? What is the easiest way to do this? - The easiest way to do this, is to access Privoxy - with your web browser at http://p.p/, - and then select - "Edit the actions list" - from the selection list. You can also do this by editing the appropriate - file with a text editor. + Actions files are just text files in a special syntax and can be edited + with a text editor. The probably easiest way is to access + Privoxy's user interface with your web browser + at http://config.privoxy.org/ + (Shortcut: http://p.p/) and then select + View & + change the current configuration from the menu. + + + + +There are several different <quote>actions</quote> files. What are +the differences? - Please see the - user-manual for a - detailed explanation of these and other configuration files, and their - various options and syntax. + As of Privoxy v2.9.15, three actions files + are being included, to be used for + different purposes: These are + default.action, the main actions file + which is actively maintained by the Privoxy + developers, user.action, where users are encouraged + to make their private customizations, and standard.action, + which is for internal Privoxy use only. + Please see the actions chapter + in the user manual for a more + detailed explanation. - + + Earlier versions included three different versions of the + default.action file. The new scheme allows for + greater flexibility of local configuration, and for browser based + selection of pre-defined aggressiveness levels. + - - What are the differences between -intermediate.action, basic.action, etc.? + + + What's the difference between the +<quote>Cautious</quote>, <quote>Medium</quote> and <quote>Advenced</quote> defaults? -Configuring Privoxy is not easy. To help you get -started, we provide you with three different default configurations. The -following table shows you, which features are enabled in each configuration. + Configuring Privoxy is not entirely trivial. To help you get + started, we provide you with three different default action packages in + the web based actions file editor at http://config.privoxy.org/show-status. + The following table shows you, which of the most important features are enabled in each + configuration: Default Configurations - + - Feature - default.action - basic.action - intermediate.action - advanced.action + Cautious + Intermadiate + Advanced - - - - - - ad-filtering - ? - x - x - x - - - - blank image - ? - x - x - x - - + - de-animate GIFs - ? - x - x - x + Ad-blocking by URL + yes + yes + yes - + - referer forging - ? - x - x - x + Ad-filtering by size + yes + yes + yes - + - jon's +no-cookies-keep (i.e. session cookies only) - ? - x - x - x + GIF de-animation + no + yes + yes - + - no-popup windows - ? - - x - x + Referer forging + no + yes + yes - + - fast redirects - ? - - x - x + Cookie handling + none + session-only + kill - + - hide-referrer - ? - - x - x + Pop-up killing + no + no + yes - + - hide-useragent - ? - - x - x + Fast redirects + no + no + yes - + - content-modification - ? - - - x + HTML taming + yes + yes + yes - + - feature-x - ? - - - + JavaScript taming + yes + yes + yes - + - feature-y - ? - - - + Web-bug killing + yes + yes + yes - + - feature-z - ? - - - + Fun text replacements + no + no + yes - +
- + + Where the defaults are likely to break some sites, exceptions for + known popular problem sites are included, but in + general, the more aggressive your default settings are, the more + exceptions you will have to make later. See the user manual for a more + deatiled discussion. + + + - Why can I change the configuration with a -browser? Does that not raise security issues? + Why can I change the configuration +with a browser? Does that not raise security issues? -What I don't understand, is how I can browser edit the config file as a -regular user, while the whole /etc/privoxy hierarchy belongs to the user -"privoxy", with only 644 perms. + It may seem strange that regular users can edit the config files with their + browsers, although the whole /etc/privoxy hierarchy + belongs to the user privoxy, with only 644 permissions. -When you use the browser-based editor, Privoxy -itself is writing to the config files. Because -Privoxy is running as the user "privoxy", it can -update the config files. + When you use the browser-based editor, Privoxy + itself is writing to the config files. Because + Privoxy is running as the user privoxy, + it can update the config files. -If you don't like this, setting "enable-edit-actions 0" in the config file -will disable the browser-based editor. If you're that paranoid, you should -also consider setting "enable-remote-toggle 0" to prevent browser-based -enabling/disabling of Privoxy. + If you run Privoxy for multiple untrusted users (e.g. in + a LAN), you will probably want to turn the web-based editor and remote toggle + features off by setting enable-edit-actions + 0 and enable-remote-toggle + 0 in the main configuration file. -Note that normally only local users can connect to Privoxy, so this is not -(normally) a security problem. + Note that in the default configuration, only local users (i.e. those on + localhost) can connect to Privoxy, + so this is not (normally) a security problem. - + - -What is a <quote>default.filter</quote>? + +What is the <filename>default.filter</filename> file? - The default.filter file is used to filter any - page content. By filtering we mean it can modify, remove, - or change anything on the page, including HTML tags, and - JavaScript. Regular expressions are used to accomplish this. This is - potentially a very powerful feature, but requires some expertise. + The default.filter + file is where filters are defined, which can be used to modify or + remove, web page content on the fly. This applies to anything + in the page source, including HTML tags, and JavaScript. Regular expressions are used + to accomplish this. There are a number of pre-defined filters to deal with common + annoyances. The filters are only defined here, to invoke them, you need to use the + filter action. If you are familiar with regular expressions, and HTML, you can look at - the provided default.filter with a text editor and see - some of things it can be used for. + the provided default.filter with a text editor and define + your own filters. This is potentially a very powerful feature, but + requires some expertise. Presently, there is no GUI editor option for this part of the configuration, - but you can disable/enable various sections of the included default - file with the Actions List Editor from your browser. + but you can disable/enable the various pre-defined filters of the included + default.filter file with the web-based actions file editor. - + - + How can I set up <application>Privoxy</application> to act as a proxy for my LAN? By default, Privoxy only responds to requests - from localhost. To have it act as a server for a network, this needs to be - changed in the main config file where the Privoxy - configuration is located. In that file is a listen-address - option. It may be commented out with a # symbol. Make sure - it is uncommented, and assign it the address of the LAN gateway interface, - and port number to use: + from 127.0.0.1 (localhost). To have it act as a server for + a network, this needs to be changed in the main configuration file. Look for + the listen-address + option, which may be commented out with a # symbol. Make sure + it is uncommented, and assign it the address of the LAN gateway interface, + and port number to use. Assuming your LAN address is 192.168.1.1 and you + wish to run Privoxy on port 8118, this line + schould look like: - listen-address 192.168.1.1:8118 - + listen-address 192.168.1.1:8118 @@ -739,70 +813,222 @@ Note that normally only local users can connect to Privoxy - + + If you run Privoxy on a LAN with untrusted users, + we recommend that you double-check the access control and security + options! + + - + + Instead of ads, now I get a checkerboard pattern. I don't want to see anything. - This is a configuration option for images that - Privoxy is stopping. You have the choice a checkerboard - pattern (this scales better), a transparent 1x1 GIF image, or a custom URL or - your choice. + The replacement for blocked images can be controlled with the set-image-blocker + action. You have the choice of a checkerboard pattern, a transparent 1x1 GIF + image (aka blank), or a redirect to a custom image of your choice. + Note that this choice only has effect for images which are blocked as images, i.e. + whose URLs match both a handle-as-image + and block action. + + + If you want to see nothing, then change the set-image-blocker + action to blank. This can be done by editing the + default.action file, or trough the web-based actions file editor. + + + +Why would anybody want to see a checkerboard pattern? - If you want to see nothing, then change the +image-blocker - action to +image-blocker{blank}. This can be done from the - Edit Actions List selection at http://p.p/. Or by hand editing the appropriate - actions file. This will only effect what is defined as images - though. + Remember that telling which image is an ad and which + isn't, is mostly guesswork. While we hope that the standard configuration + is rather smart, it can and will make errors. The checkerboard image is visually + decent, but it shows you that and where images were blocked, which can be very + helpful in case some navigation aid or otherwise innocent image was + erraneously blocked. Some people might also enjoy seeing how many banners + they don't have to see.. + + + + + + +I see some images being replaced by a text +instead of the checkerboard image. Why and how do I get rid of this? - These are URLs that match something in one of - Privoxy's block actions (+block). It is meant - to be a warning so that you know something has been blocked and an easy way - for you to see why. These are handled differently than what has been defined - as images (e.g. ad banners). If you want them to be treated - as if they were images, so that they can be invisible, then move the - offending URL from the +block section to the - +imageblock section of your actions file. Alternately, you - could modify the block HTML template that - is used by Privoxy to display this, and make it - something more to your liking. + This happens when the banners are not embedded in the HTML code of the + page itself, but in separate HTML (sub)documents that are loaded into (i)frames + or (i)layers, and these external HTML documents are blocked. Being non-images + they get replaced by a substitute HTML page rather than a substitute image, + which wouldn't work out technically, since the browser expects and accepts + only HTML when it has requested an HTML document. + + + The substitute page adapts to the available space and shows itself as a + miniature two-liner if loaded into small frames, or full-blown with a + large red "BLOCKED" banner if space allows. + + If you prefer the banners to be blocked by images, you must see to it that + the HTML documents in which they are embedded are not blocked. Clicking + the See why link offered in the substitute page will show + you which rule blocked the page. After changing the rule and un-blocking + the HTML documents, the browser will try to load the actual banner images + and the usual image blocking will (hopefully!) kick in. + + - + +Can <application>Privoxy</application> run as a service +on Win2K/NT? + + Yes, it can run as a system service using srvany.exe. + The only catch is that this will effectively disable the + Privoxy icon (and its menu!) in the taskbar. You can have + one or the other, but not both at this time :( + + + There is a pending feature request for this functionality. See the discussion + at http://sourceforge.net/tracker/?func=detail&atid=361118&aid=485617&group_id=11118, + for details, and a sample configuration. + + + + +How can I make <application>Privoxy</application> work with other +proxies like <application>Squid</application>? + + This can be done and is often useful to combine the benefits of + Privoxy with those of a caching proxy. + See the forwarding chapter + in the user manual which + describes how to do this. + + + + +Can <application>Privoxy</application> run as a <quote>transparent +</quote> proxy? + + No, Privoxy currently does not have this ability, + though it is planned for a future release. Transparent proxies require + special handling of the request headers beyond what + Privoxy is now capable of. + + + + Chaining Privoxy behind another proxy that has + this ability should work though. + See the forwarding chapter + in the user manual. As + a transparent proxy to be used for chaining we recommend Transproxy + (http://www.transproxy.nlc.net.au/). + + + + + + + + + -Misc +Miscellaneous - + How much does <application>Privoxy</application> slow my browsing down? This has to add extra time to browsing. @@ -815,135 +1041,133 @@ has to add extra time to browsing. - Filtering via the filterfile - mechanism may cause a perceived slowdown, since the entire page is buffered + Filtering content via the filter or + deanimate-gifs + actions may cause a perceived slowdown, since the entire document needs to be buffered before displaying. See below. - - + -I noticed considerable +<sect2 renderas="sect3" id="loadingtimes"><title>I noticed considerable delays in page requests compared to the old Junkbuster. What's wrong? -Using the default filtering configuration, I noticed considerable delays in -page requests compared to the old Junkbuster. Loading pages with large contents -seemed to take forever, then suddenly delivering all the content at once. - + If you use any filter action, + such as filtering banners by size, web-bugs etc, or the deanimate-gifs + action, the entire document must be loaded into memory in order for the filtering + mechanism to work, and nothing is sent to the browser during this time. + -The whole content must be loaded in order to filter, and nothing is is -sent to the browser during this time. The loading time does not really -change in real numbers, but the feeling is different, because most -browsers are able to start rendering incomplete content, giving the -user a feeling of "it works". + The loading time does not really change in real numbers, but the feeling is + different, because most browsers are able to start rendering incomplete + content, giving the user a feeling of "it works". This effect is especially + noticeable on slow dialup connections. - -To modify the content of a page (i.e. make frames resizeable again, etc.) and -not just replace ads, Privoxy needs to download the -entire page first, do its content magic and then send the page to the browser. - - + -What is the "http://p.p/"? +What are "http://config.privoxy.org/" and +"http://p.p/"? -Since Privoxy sits between your web browser and the Internet, it can be -programmed to handle certain pages specially. + http://config.privoxy.org/ is the + address of Privoxy's built-in user interface, and + http://p.p/ is a shortcut for it. - -With recent versions of Privoxy (version 2.9.x), you can get some -information about Privoxy and change some settings by going to -http://p.p/ or, equivalently, http://ijbswa.sourceforge.net/config/ -(Note that p.p is far easier to type but may not work in some -configurations). + Since Privoxy sits between your web browser and the Internet, + it can simply intercept requests for these addresses and answer them with its built-in + web server. - -These pages are *not* forwarded to a server on the Internet - instead they are -handled by a special web server which is built in to Privoxy. + This also makes for a good test for your browser configuration: If entering the + URL http://config.privoxy.org/ + takes you to a page saying This is Privoxy.., everything is OK. + If you get a page saying Privoxy is not working instead, then + your browser didn't use Privoxy for the request, + hence it could not be intercepted, and you have accessed the real + web site at config.privoxy.org. - -If you are not running Privoxy, then http://p.p/ will fail, and -http://ijbswa.sourceforge.net/config/ will return a web page telling you -you're not running Privoxy. + With recent versions of Privoxy (version 2.9.x and + later), the user interface features information on the run time status, the + configuration, and even a built-in editor for the actions files. -If you have version 2.0.2, then the equivalent is -http://example.com/show-proxy-args (but you get far less information, and you -should really consider upgrading to 2.9.x). + Note that the built-in URLs from earlier versions of Junkbuster + / Privoxy, http://example.com/show-proxy-args and http://i.j.b/, + are no longer supported. If you still use such an old version, you should really consider + upgrading to &p-version;. - + -Do you still maintain the blocklists? - - No. The format of the blocklists has changed significantly in the versions - 2.9.x. Once we have released the new version, there will again be - blocklists that you can update automatically. +Do you still maintain the blocklists? + + No. The patterns for blocking now reside (among other things) in the actions files, which are + actively maintained instead. See next question ... - + -How can I submit new ads? +How can I submit new ads? - As of now, please discontinue to submit new ad blocking infos. Once we - have released the new version, there will again be a form on the website, - which you can use to contribute new ads. +Yes, absolutely! Please see the Contact section for +how to do that. Please note that you (technically) need the latest +Privoxy version for this to work. - -How can I hide my IP address? + + +How can I hide my IP address? - You cannot hide your IP address with Privoxy or any other software, since -the server needs to know your IP address to send the answer to you. + If you run both the browser and the proxy locally, you cannot hide your IP + address with Privoxy or any other software. The + server needs to know your IP address to send the answers back to you. -Fortunately there are many publicly usable anonymous proxies out there, which -solve the problem by providing a further level of indirection between you and -the web server, shared by many people and thus letting your requests "drown" -in white noise of unrelated requests as far as user tracking is concerned. + Fortunately there are many publicly usable anonymous proxies out there, which + solve the problem by providing a further level of indirection between you and + the web server, shared by many people, and thus letting your requests "drown" + in white noise of unrelated requests as far as user tracking is concerned. -Most of them will, however, log your IP address and make it available to the -authorities in case you abuse that anonymity for criminal purposes. In fact -you can't even rule out that some of them only exist to *collect* information -on (those suspicious) people with a more than average preference for privacy. + Most of them will, however, log your IP address and make it available to the + authorities in case you abuse that anonymity for criminal purposes. In fact + you can't even rule out that some of them only exist to *collect* information + on (those suspicious) people with a more than average preference for privacy. -You can find a list of anonymous public proxies at multiproxy.org and many -more through Google. + You can find a list of anonymous public proxies at multiproxy.org and many + more through Google. A particularly interesting project is the JAP service + offered by the Technical University of Dresden (http://anon.inf.tu-dresden.de/index_en.html. - - - - - - - - - + + There is, however, even in the single-machine case the possibility to make the + server believe that your machine is in fact a shared proxy serving a whole big + LAN, and we are looking into that. + + - + Can <application>Privoxy</application> guarantee I am anonymous? No. Your chances of remaining anonymous are greatly improved, but unless you @@ -953,8 +1177,8 @@ more through Google. Privoxy can remove various information about you, and allows you more freedom to decide which sites - you can trust. But it's still possible that web sites can find out who you - are. Here's one way this can happen. + you can trust, and what details you want to reveal. But it's still possible + that web sites can find out who you are. Here's one way this can happen. A few browsers disclose the user's email address in certain situations, such @@ -972,11 +1196,11 @@ more through Google. Luke! - + - -Might some things break because header information is -being altered? + +Might some things break because header information or +content is being altered? Definitely. More and more sites use HTTP header content to decide what to @@ -985,10 +1209,10 @@ being altered? - USER AGENT in particular is often used in this way to identify - the browser, and adjust content accordingly. Changing this now is not - recommended, since so many sites do look for this. You may get undesirable - results by changing this. + User-Agent in particular is often used in this way to identify + the browser, and adjust content accordingly. Changing this now (at least not + further than removing the OS information) is not recommended, since so many + sites do look for it. You may get undesirable results by changing this. @@ -998,44 +1222,53 @@ being altered? operating system or browser manufacturer causes some sites in these languages to be garbled; Surfers to Eastern European sites should change it to something closer. And then some page access counters work by looking at the - REFERER header; they may fail or break if unavailable. The + Referer header; they may fail or break if unavailable. The weather maps of Intellicast have been blocked by their server when no - REFERER or cookie is provided, is another example. There are - many, many other ways things can go wrong when trying to fool a web server. + Referer or cookie is provided, is another example. (But you + can forge both headers without giving information away). There are + many other ways things can go wrong when trying to fool a web server. + + + + Similar thoughts apply to modifying JavaScript, and, to a lesser degree, + HTML elements. If you have problems with a site, you will have to adjust your configuration accordingly. Cookies are probably the most likely adjustment that may be required, but by no means the only one. - - + - + Can <application>Privoxy</application> act as a <quote>caching</quote> proxy to speed up web browsing? No, it does not have this ability at all. You want something like Squid for this. And, yes, before you ask, Privoxy can co-exist - with other kinds of proxies like Squid. + with other kinds of proxies like Squid. + See the forwarding + chapter in the user + manual for details. - + - + What about as a firewall? Can <application>Privoxy</application> protect me? - Not in the way you mean, or in the way a true firewall can, or a proxy that - has this specific capability. Privoxy can help - protect your privacy, but not really protect you from intrusion attempts. + Not in the way you mean, or in the way a true firewall can. + Privoxy can help protect your privacy, but not + protect you from intrusion attempts. It is, of course, perfectly possible + and recommended to use both. - - + - + - -I have large empty spaces now where ads used to be. -Why does <application>Privoxy</application> leave these large gaps? + +I have large empty spaces / a checkerboard pattern now where +ads used to be. Why? - It would be easy enough to just eliminate this space altogether, rather than - fill it with blank space. But, this would create problems with many pages - that use the overall size of the ad to help organize the page layout and - position the various components of the page where they were intended to be. - It is best left this way. + It would be technically possible eliminate the banners in a way that frees + their screen estate in many cases, by doing all banner blocking with filters, + i.e. eliminating the whole image references from the HTML pages instead + of letting them stay in, and blocking the resulting requests for the + banners themselves. + + But this would consume considerable CPU resources, would likely destroy + the layout of many web pages which rely on the banners consuming a certain + amount of screen space, and would fail in other cases, where the screen space + is reserved e.g. by tables anyway. Also, making the banners disappear without + a visual trace complicates troubleshooting. + + + So we won't support this in the default configuration, but you can of course + define appropriate filters yourself. + + - - - + How can <application>Privoxy</application> filter Secure (HTTPS) URLs? - This is a limitation since HTTPS transactions are encrypted SSL sessions - between your browser and the secure site, and are meant to be reliably - secure and private. This means that all cookies and HTTP - header information are also encrypted from the time they leave your browser, - to the site, and vice versa. Privoxy does not - try to unencrypt this information, so it just passes through as is. - Privoxy can still catch images and ads that - are embedded in the SSL stream though. + Since secure HTTP connections are encrypted SSL sessions between your browser + and the secure site, and are meant to be reliably secure, + there is little that Privoxy can do but hand the raw + gibberish data though from one end to the other unprocessed. + + + The only exception to this is blocking by host patterns, as the client needs + to tell Privoxy the name of the remote server, + so that Privoxy can establish the connection. + If that name matches a host-only pattern, the connection will be blocked. + + + As far as ad blocking is concerned, this is less of a restriction than it may + seem, since ad sources are often identifiable by the host name, and often + the banners to be placed in an encrypted page come unencrypted nonetheless + for efficiency reasons, which exposes them to the full power of + Privoxy's ad blocking. - - + - + <application>Privoxy</application> runs as a <quote>server</quote>. How secure is it? Do I need to take any special precautions? - There are no known exploits that might effect + There are no known exploits that might affect Privoxy. On Unix-like systems, Privoxy can run as a non-privileged user, which is how we recommend it be run. Also, by default Privoxy only listens to requests - from localhost. It is not itself directly exposed to the + from localhost only. The server aspect of + Privoxy is not itself directly exposed to the Internet in this configuration. If you want to have Privoxy serve as a LAN proxy, this will have to be opened up to allow for LAN requests. In this case, we'd recommend - you specify only the LAN gateway address, e.g. 192.168.1.1 in the main - Privoxy config file. All LAN hosts can then use - this as their proxy address in the browser proxy configuration. In this way, - Privoxy will not listen on any external ports. - Of course, a firewall is always good too. Better safe than sorry. + you specify only the LAN gateway address, e.g. 192.168.1.1, in the main + Privoxy configuration file and check all access control and security + options. All LAN hosts can then use this as their proxy address + in the browser proxy configuration, but Privoxy + will not listen on any external interfaces. ACLs can be defined in addition, + and using a firewall is always good too. Better safe than sorry. - + + + +How can I temporarily disable <application>Privoxy</application>? + + The easiest way is to access Privoxy with your + browser by using the remote toggle URL: http://config.privoxy.org/toggle. + + + +Where can I find more information about <application>Privoxy</application> +and related issues? + + &seealso; + + + + + - -Troubleshooting + +Troubleshooting - + I just upgraded and am getting <quote>connection refused</quote> with every web page? @@ -1128,14 +1408,15 @@ with every web page? default. This has been changed to port 8118 now, due to a conflict with NAS (Network Audio Service), which uses port 8000. If you haven't, you need to change your browser to the new port number, or alternately - change Privoxy's listen-address - setting in the config file used to start - Privoxy. + change the listen-address + option in Privoxy's main configuration file. - + - + I just added a new rule, but the steenkin ad is still getting through. How? @@ -1149,86 +1430,127 @@ still getting through. How? If this doesn't help, you probably have an error in the rule you applied. Try pasting the full URL of the offending ad into http://ijbswa.sourceforge.net/config/show-url-info - and see if any actions match your new rule. + url="http://config.privoxy.org/show-url-info">http://config.privoxy.org/show-url-info + and see if it really matches your new rule. - + - + One of my favorite sites does not work with <application>Privoxy</application>. What can I do? First verify that it is indeed a Privoxy problem, - by disabling Privoxy filtering and blocking. - Go to http://p.p/ and click on - Toggle Privoxy On or Off, then disable it. Now try that - page again. + by toggling off Privoxy through http://config.privoxy.org/toggle, + and then shift-reloading the problem page (i.e. holding down the shift key + while clicking reload. Alternatively, flush your browser's disk and memory + caches). - If still a problem, go to Show which actions apply to a URL and - why from http://p.p/ and paste - the full URL of the page in question into the prompt. See which actions are - being applied to the URL. Now, armed with this information, go to Edit - the actions list. Here you should see various sections that have - various Privoxy features disabled for specific - sites. Disabled actions will have a - (minus - sign) in front of them. Add your problem page URL to one of these sections - that looks like it is disabling the feature that is causing the - problem. Re-try the page. There might be some trial and error involved. This - is discussed in a little more detail in the user-manual - appendix. - + If still a problem, go to http://config.privoxy.org/show-url-info + and paste the full URL of the page in question into the prompt. See which actions + are being applied to the URL, and which matches in which actions files are + responsible for that. Now, armed with this information, go to http://config.privoxy.org/show-status + and select the appropriate actions files for editing. + + + You can now either look for a section which disables the actions that + you suspect to cause the problem and add a pattern for your site there, + or make up a completely new section for your site. In any case, the recommended + way is to disable only the prime suspect, reload the problem page, and only + if the problem persists, disable more and more actions until you have + identified the culprit. You may or may not want to turn the other actions + on again. Remember to flush your browser's caches in between any such changes! - Alternately, if you are comfortable with a text editor, you can accomplish - the same thing by editing the appropriate actions file. + the same thing by editing the appropriate actions file. Probably the easiest + way to deal with such problems when editing by hand is to add your + site to a { fragile } section in user.action, + which is an alias that turns off most dangerous + actions, but is also likely to turn off more actions then needed, and thus lower + your privacy and protection more than necessary, - - - - -What time is it? - Time for you to go! + Troubleshooting actions is discussed in more detail in the user-manual appendix. + There is also an actions tutorial. - - + - -Contact the developers -Please see the user manual for information on how to contact the developers. - - + + Contacting the developers, Bug Reporting and Feature Requests + + &contacting; + + + -Copyright and History -Please see the user manual for information on Copyright and History. - - +Privoxy Copyright, License and History + + + ©right; + + + + Portions of this document are borrowed from the original + Junkbuster (tm) FAQ, and modified as + appropriate for Privoxy. + + + License + + &license; + + + + + + History + + &history; + + + + + + + + + + + +