From 0be6c4d411b319c9dc6f7b8894a32f8fb5aeff0e Mon Sep 17 00:00:00 2001 From: oes Date: Wed, 22 May 2002 17:17:48 +0000 Subject: [PATCH] Proofread & added more links into u-m --- doc/source/faq.sgml | 1069 +++++++++++++++++++++++-------------------- 1 file changed, 567 insertions(+), 502 deletions(-) diff --git a/doc/source/faq.sgml b/doc/source/faq.sgml index 852aa662..e3a23012 100644 --- a/doc/source/faq.sgml +++ b/doc/source/faq.sgml @@ -24,14 +24,14 @@ This file belongs into ijbswa.sourceforge.net:/home/groups/i/ij/ijbswa/htdocs/ - $Id: faq.sgml,v 1.58 2002/05/10 01:48:20 hal9 Exp $ + $Id: faq.sgml,v 1.59 2002/05/15 04:03:30 hal9 Exp $ Copyright (C) 2001, 2002 Privoxy Developers See LICENSE. Based partially on the Internet Junkbuster FAQ originally written by and Copyright (C) 1997 Anonymous Coders and Junkbusters Corporation. - http://www.junkbusters.com + http://www.junkbusters.com/ @@ -72,7 +72,7 @@ -$Id: faq.sgml,v 1.58 2002/05/10 01:48:20 hal9 Exp $ +$Id: faq.sgml,v 1.59 2002/05/15 04:03:30 hal9 Exp $ @@ -138,27 +139,10 @@ Hal. General Information 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 result - of this effort is Privoxy. - - - Privoxy has evolved from the - Junkbuster 2.0.2 code base, and has advanced - significantly at this point. - - - Please see the History section for more - information on the history of Junkbuster and - Privoxy. - + + + &history; + @@ -167,18 +151,25 @@ Hal. Why <quote>Privoxy</quote>? Why a name change at all? Privoxy is the - Privacy Enhancing Proxy. + Privacy Enhancing Proxy. Also, its content + modification and junk suppression allow you to browse your + private edition of the web. + + + 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 potential legal complications from the continued use of the + There are also potential legal complications from the continued use of the Junkbuster name, which is a registered trademark of - Junkbusters Corporation. - And thus they own the rights to the name. - (There are, however, no objections from Junkbusters Corporation to the + 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.) + 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 @@ -191,23 +182,25 @@ Hal. 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. + 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 if you are upgrading from - Junkbuster 2.0.x. 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. - - + 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. + + + Privoxy's new features include: + -What are some of the new features? &newfeatures; @@ -217,57 +210,54 @@ from the old Junkbuster? 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. - - + How does <application>Privoxy</application> know what is an ad, and what is not? - Privoxy processes all the raw content of every - web page. So it reads everything on each page. It then compares this to the - rules as set up in the configuration files, and looks for any matches to - these rules. Privoxy makes heavy use of - regular expressions. (If you are not familiar with regular - expressions, it is explained briefly in the user manual.) Regular - expressions facilitate matching of one text string against another, using - wildcards to build complex patterns. So Privoxy - will typically look for URLs and other content that match certain key words - and expressions as defined in the configuration files. For instance a URL - that contains /banners, has a high probability of containing - ad banners, and thus would be a prime candidate to have a matching rule. - - - So Privoxy will look for these kinds of obvious - looking culprits. And also, will use lists of known organizations that - specialize in ads. Again, using complex patterns to match as many potential - combinations as possible since there tend to be many, many variations used by - advertisers, and new ones are being introduced all the time. + 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. @@ -275,10 +265,10 @@ an ad, and what is not? 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 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. + Actually, it's a black art ;-) And yes, it is always possible to have a broad + rule accidentally block of 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. @@ -306,7 +296,6 @@ This does not sound very scientific. 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. - @@ -315,20 +304,18 @@ This does not sound very scientific. 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. Please see the Copyright section for more information on the - license and copyright. Or the LICENSE file + 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! - @@ -337,23 +324,37 @@ warranty? Registration? 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. + + + +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 - Developer's 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. @@ -369,10 +370,10 @@ warranty? Registration? Which browsers are supported by <application>Privoxy</application>? - Any browser that can be configured to use a proxy, which + 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 - just exchanges standard HTML data with your browser, just like a web server + talks to the browser in the standardized HTTP protocol, just like a web server does. @@ -388,18 +389,17 @@ Include supported.sgml here: Can I install <application>Privoxy</application> over <application>Junkbuster</application>? - We recommend you uninstall 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. - - - See the user-manual for - platform specific installation instructions. + 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. - Note: Some installers may automatically uninstall + Note: Some installers may automatically un-install Junkbuster, if present! @@ -413,8 +413,8 @@ 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. - Also, you should flush your browser's memory and disk cache to get rid of any - cached items. + You should also flush your browser's memory and disk cache to get rid of any + cached junk items. @@ -427,23 +427,25 @@ special I have to do now? 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). + 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 @@ -462,11 +464,17 @@ 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. + @@ -481,13 +489,14 @@ All the ads are there. What's wrong? Can I use my old config files? - There are major changes to Junkbuster/ - Privoxy configuration from version 2.0.x to - 2.9.x and later. Most of the older files will not work at all. This is - especially true of blocklist. 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. @@ -495,40 +504,37 @@ All the ads are there. What's wrong? 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 where needed. + 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 - 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. @@ -538,20 +544,13 @@ some of these actions. 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 - "View & change the current configuration" - from the selection list. You can also do this by editing the appropriate - file with a text editor. - - - - Please see the - user-manual for a - detailed explanation of these and other configuration files, and their - various options and syntax. + 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. @@ -563,244 +562,225 @@ the differences? As of Privoxy v2.9.15, three actions files are being included, to be used for - different purposes. These are - default.action, standard.action, - and user.action. Please see - the User Manual - for an explanation of each. + 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 - default.action files. The new scheme allows for + 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 - configuration. + selection of pre-defined aggressiveness levels. - - - - + - 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 permissions. + 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 <quote>default.filter</quote>? - - The default.filter file is where filters - are defined, which are used to filter any - web 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, and operate - on a line by line basis. This is potentially a very powerful feature, but - requires some expertise. +What is the <filename>default.filter</filename> file? + + 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 View & change the current configuration 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. @@ -811,17 +791,19 @@ problem. 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 + changed in themain 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: + 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 @@ -829,47 +811,55 @@ problem. all browsers on the network then to use this address and port number. + + 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 of a - checkerboard pattern, a transparent 1x1 GIF image (aka blank), - or a custom URL of your choice. Note that to fit this category, the URL must - match both the +handle-as-image - and - +block actions. + 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 +image-blocker{blank}. This can be done from the - View & change the current configuration selection at http://p.p/. Or by hand editing the appropriate - actions file. This will only effect what is defined as images - though. Also, some URLs that generate the bright red Blocked - banner, can be moved to the +set-image-blocker section for the - same reason, but there are some limits and risks to this (see below). + 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? - This can be helpful for troubleshooting problems. It might also be good - for anyone new to Privoxy so that they can - see if their favorite pages are displaying correctly, and - Privoxy is not inadvertently removing something - important. + 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? + + 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 in the taskbar. You can have + 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 - thread: http://sourceforge.net/tracker/?func=detail&atid=361118&aid=485617&group_id=11118, for details, and a sample configuration. @@ -967,9 +986,12 @@ on Win2K/NT? How can I make <application>Privoxy</application> work with other proxies like <application>Squid</application>? - This can be done. See the user manual, - which describes how to do this. + 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. @@ -984,11 +1006,13 @@ proxies like Squid? - Chaining Privoxy with another proxy that has + Chaining Privoxy behind another proxy that has this ability should work though. - See the user - manual, which describes this, and also http://www.transproxy.nlc.net.au/. + 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/). @@ -1015,8 +1039,11 @@ 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. @@ -1026,56 +1053,55 @@ has to add extra time to browsing. I noticed considerable delays in page requests compared to the old Junkbuster. What's wrong? -The entire page content must be loaded into memory in order for the filtering -mechanism to work, and nothing 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". - - - 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. + 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 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. + -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 and - greater), you can get some information about - Privoxy and change some settings by going to - http://p.p/ or, equivalently, http://config.privoxy.org/ (Note - that p.p is far easier to type but may not work in some configurations. With - the name change to Privoxy, this is changed from - the previous http://i.j.b/ and earlier 2.9.x versions). + 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://config.privoxy.org/ 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 &p-version;). + 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;. @@ -1084,64 +1110,61 @@ FIXME: commented out until we have data. HB 03/18/02. I get the message 'Bad File Descriptor', why? - Fillme. + Fill me. --> Do you still maintain the blocklists? - - No, not by this name. The format of the blocklists has changed - significantly in versions 2.9.x and later. This functionality - is done by the actions file now. See next question ... + + 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? -Please see the Contact section. - - - - This process does not work with earlier versions of Privoxy - or Junkbuster. +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? - You cannot hide your IP address with Privoxy or any other software, since -the server needs to know your IP address to send the answers back 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. A particularly interesting project is the JAP service + offered by the Technical University of Dresden (http://anon.inf.tu-dresden.de/index_en.html. -You can find a list of anonymous public proxies at multiproxy.org and many -more through Google. + 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? @@ -1174,8 +1197,8 @@ more through Google. -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 @@ -1184,10 +1207,10 @@ 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. @@ -1197,10 +1220,16 @@ 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. @@ -1220,19 +1249,23 @@ speed up web browsing? Squid for this. And, yes, before you ask, Privoxy can co-exist 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? +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. The server aspect of + 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. + 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. @@ -1309,9 +1362,8 @@ secure is it? Do I need to take any special precautions? How can I temporarily disable <application>Privoxy</application>? The easiest way is to access Privoxy with your - browser by using the special URL: http://p.p/ - and select "Toggle Privoxy on or off" from that page. - + browser by using the remote toggle URL: http://config.privoxy.org/toggle. @@ -1354,9 +1406,10 @@ 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. @@ -1376,7 +1429,7 @@ 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://config.privoxy.org/show-url-info - and see if any actions match your new rule. + and see if it really matches your new rule. @@ -1387,36 +1440,45 @@ 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. It's probably a good idea to flush the browser cache as well - with Shift+Reload to flush 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 - View & change the current configuration. Here you should see various sections that have - various Privoxy features disabled for specific - sites. Most disabled actions will have a - (minus - sign) in front of them. Some aliases are used just to disable other actions, - e.g. shop and fragile, and won't necessarily - use a + or - sign. Add your problem page - URL to one of these sections that looks like it is disabling the feature that - is causing the problem. Rember to flush your browser's caches when making - such changes! As a last resort, try fragile which - disables most actions. Now re-try the page. There might be some trial and - error involved. This is discussed in more detail in the user-manual appendix. - + 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 browsers' disk any memory + caches). + + 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. The probably 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, + + + Troubleshooting actions is discussed in more detail in the user-manual appendix. + There is also an actions tutorial. @@ -1431,7 +1493,7 @@ What can I do? FIXME: Commented out until we have something to put here. HB 03/18/02. Known Issues - Fillme. + Fill me. --> @@ -1513,6 +1575,9 @@ FIXME: Commented out until we have something to put here. HB 03/18/02. Temple Place - Suite 330, Boston, MA 02111-1307, USA. $Log: faq.sgml,v $ +Revision 1.59 2002/05/15 04:03:30 hal9 +Fix ulink -> link markup. + Revision 1.58 2002/05/10 01:48:20 hal9 This is mostly proposed copyright/licensing additions and changes. Docs are still GPL, but licensing and copyright are more visible. Also, copyright -- 2.39.2