X-Git-Url: http://www.privoxy.org/gitweb/?p=privoxy.git;a=blobdiff_plain;f=doc%2Fsource%2Ffaq.sgml;h=9e83033131505ed7629fd851cbc87fb8d07a6fa2;hp=1713381ad271cf0e91b5cd661cdc5ebe3b645506;hb=ba215fa6bb4d5293cff0a7b9b399d075f990300d;hpb=c25d4903b8214091cc41df10d74b627412d2902f diff --git a/doc/source/faq.sgml b/doc/source/faq.sgml index 1713381a..9e830331 100644 --- a/doc/source/faq.sgml +++ b/doc/source/faq.sgml @@ -1,4 +1,20 @@ - + + + + + + + + + + + + + + + +]> -
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-Junkbuster Frequently Asked Questions +Privoxy Frequently Asked Questions -$Id: faq.sgml,v 1.12 2002/03/11 20:13:21 swa Exp $ +$Id: faq.sgml,v 1.44 2002/04/07 21:24:29 hal9 Exp $ - By: Junkbuster Developers + By: Privoxy Developers + + + 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 the Internet Junkbuster. Internet -Junkbuster 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. Junkbuster has a very flexible configuration and can be -customized to suit individual needs and tastes. Internet -Junkbuster has application for both stand-alone systems and -multi-user networks. + This FAQ gives users and developers alike answers to frequently asked + questions about Privoxy + . + + + &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. @@ -53,190 +102,180 @@ Please see the Contact section in the user-manual if you want to contact the dev - - - + + ---> - - -Frequently Asked Questions -General Information +General Information -What is this new <application>Junkbuster</application>? +What is this new version of <application>Privoxy</application>? - The original Junkbuster was a product of - Junkbusters Corporation (tm). Development of this effort stopped - as of version 2.0.2. Stefan Walherr started the ijbswa project on - Sourceforge to - rekindle development. Other developers subsequently joined with - Stefan, and have since added many new features and enhancements. + 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. - - -How does it differ from the old <application>Junkbuster?</application> - All the old features remain. The new Junkbuster - still blocks ads and banners, still manages cookies, and protects - privacy. But, these are all enhanced, and many new features have been - added, all in the same vein. + Privoxy has evolved from the + Junkbuster 2.0.2 code base, and has advanced + significantly at this point. - - The configuration has changed significantly. 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 ijb.actions. This is where most of - the per site configuration is now. - + + Please see the History section for more + information on the history of Junkbuster and + Privoxy. - - -What are some of the new features? - - - - - - - Integrated browser based configuration and control utility (http://i.j.b). 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). - - + +Why <quote>Privoxy</quote>? Why a name change at all? + + Privoxy is the + Privacy Enhancing Proxy. + + + There are 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 + Privoxy project itself, and they, in fact, still + share our ideals and goals.) + - - - Improved cookie management features (e.g. session based cookies). - - + + 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. + + - - - 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. - - +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 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. + + - - +What are some of the new features? + + &newfeatures; + - + -How does <application>Junkbuster</application> - work? What is a <quote>proxy</quote>? +What is a <quote>proxy</quote>? How does +<application>Privoxy</application> work? - When you connect to a web site with Junkbuster, + When you connect to a web site with Privoxy, you are really connecting to your locally running version of - Junkbuster. Junkbuster + 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 Junkbuster, where - Junkbuster can work its magic before it + back to Privoxy, where + Privoxy can work its magic before it relays this data back to your web browser. - - Since Junkbuster sits between you and the + 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. - Junkbuster uses various programming methods to do + Privoxy uses various programming methods to do this, all of which is under your control via the various configuration - files. + files and options. + + + There are many kinds of proxies. Privoxy best + fits the filtering proxy category. - -My browser does the same things as -Junkbuster. Why should I use Junkbuster at all? + + + + +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. + + + + +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. + + + + 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? Modern browsers do indeed have some of the same - functionality as Junkbuster. Maybe this is - adequate for you. But Junkbuster is much more - verstatile and flexible, and can do some things that browsers just can't. + functionality as Privoxy. Maybe this is + adequate for you. But Privoxy is much more + versatile and powerful, and can do a number of things that browsers just can't. In addition, a proxy is good choice if you use multiple browsers, or @@ -245,114 +284,278 @@ Junkbuster. Why should I use Junkbuster at all? 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? - Junkbuster is licensed under the - GNU General Public License (GPL). It is free to use, copy, - modify or distribute as you wish. - + 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. + + - There is no warranty of any kind, expressed, implied or otherwise. That is something - that would cost real money ;-) There is no registration either. - Junkbuster really is free + 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? + +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. + +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. + + + 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 -Can I install the new - <application>Junkbuster</application> over the old one? +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 + just exchanges standard HTML data with your browser, just like a web server + does. + + + + +Which operating systems are supported? + +&supported; + + +Can I install + <application>Privoxy</application> over <application>Junkbuster</application>? - We recommend you uninstall the old Junkbuster + We recommend you uninstall Junkbuster first to minimize conflicts and confusion. You may want to - save your old configuration files for future reference. + save your old configuration files for future reference. The configuration + is substantially changed. - See the user-manual for platform specific installation instructions. - + See the user-manual for + platform specific installation instructions. - - + + Note: Some installers may automatically uninstall + Junkbuster, if present! + + + + + +I just installed <application>Privoxy</application>. Is there anything +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. + + -What is the proxy address of Junkbuster? + + + +What is the proxy address of <application>Privoxy</application>? - If you set up the Junkbuster to run on + 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 told the Internet - Junkbuster to run on a different port with the + to itself) and the port will be 8118 (unless you have Privoxy to run on a different port with the listen-address config option). - So you when configuring your browser's proxy settings you typically enter + 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. + for port. This tells your browser to send all web + requests to Privoxy instead of directly to the + Internet. - Junkbuster can also be used to proxy for + 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 Junkbuster + address of the LAN host where Privoxy is running, or the equivalent hostname. Port assignment would be same as above. - Junkbuster does not currently handle + 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? + + + Did you configure your browser to use Privoxy + as a proxy? It does not sound like it. See above. You might also try flushing + 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. + + + + + -Configuration +Configuration -Can I use my old config files? +Can I use my old config files? - No. These will not work. You will need to re-enter your old - data into the new configuration structure. + 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. - + + + +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 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. + + + + + 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 +some of these <quote>actions</quote>. + + These are all explained in the + user-manual. + Please refer to that. + + + + +How are actions files configured? What is the easiest +way to do this? -How can I make my Yahoo account work? + + 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. + + + + Please see the + user-manual for a + detailed explanation of these and other configuration files, and their + various options and syntax. + + + + + - What are the differences between -ijb-intermediate.action, ijb-basic.action, etc.? + What are the differences between +intermediate.action, basic.action, etc.? -Configuring the Internet Junkbuster 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 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. Default Configurations @@ -365,10 +568,10 @@ shows you, which features are enabled in each configuration. Feature - ijb.action - ijb-basic.action - ijb-intermediate.action - ijb-advanced.action + default.action + basic.action + intermediate.action + advanced.action @@ -492,43 +695,252 @@ shows you, which features are enabled in each configuration.
- + - Why can I change the configuration with a +<sect2 renderas="sect3" id="browseconfig"> <title>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/junkbuster hierarchy belongs to the user -"junkbuster", with only 644 perms. +regular user, while the whole /etc/privoxy hierarchy +belongs to the user privoxy, with only 644 permissions. -When you use the browser-based editor, JunkBuster itself is writing to the -config files. Because JunkBuster is running as the user "junkbuster", it can +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 JunkBuster. +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. -Note that normally only local users can connect to JunkBuster, so this is not -(normally) a security problem. +Note that normally only local users can connect to +Privoxy, so this is not (normally) a security +problem. - + + + + +What is <quote>default.filter</quote>? + + The default.filter file is 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. + + + + 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. + + + + 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. + + +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: + + + + + listen-address 192.168.1.1:8118 + + + + + Save the file, and restart Privoxy. Configure + all browsers on the network then to use this address and port number. + + + + + + +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 +image and +block actions. + + + + 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. Also, some URLs that generate the bright red Blocked + banner, can be moved to the +image-blocker section for the + same reason, but there are some limits and risks to this (see below). + + + + + + +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. + + + + + +I see large red banners on some pages that say +<quote>Blocked</quote>. 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 + explicitly as images (e.g. ad banners). Depending on the + URL itself, it is sometimes hard for Privoxy to + really know whether there is indeed an ad image there or not. And there are + limitations as to what Privoxy can do to + fool the browser. + + + + For instance, if the ad is in a frame, then it is embedded in the separate + HTML page used for the frame. In this case, you cannot just substitute an + aribitray image (like we would for a blank image), for an HTML + page. The browser is expecting an HTML page, and that is what it must have + for frames. So this situation can be a little trickier to deal with, and + Privoxy will use the Blocked page. + + + + If you want these to be treated as if they were images, so that they can be + made invisible, you can try moving the offending URL from the + +block section to the +imageblock section of + your actions file. Just be forewarned, if any URL is made + invisible, you may not have any inkling that something has + been removed from that page, or why. If this approach does not work, then you are + probably dealing with a frame (or ilayer), and the only thing + that can go there is an HTML page of some sort. + + + To deal with this situation, you could modify the + block HTML template that is used by + Privoxy to display this, and make it something + more to your liking. Currently, there is no configuration option for this. + You will have to modify, or create your own page, and use this to replace + templates/blocked, which is what + Privoxy uses to display the Blocked + page. + + + Another way to deal with this is find why and where + Privoxy is blocking the frame, and + diable this. Then let the +image-blocker action + handle the ad that is embedded in the frame's HTML page. + + + + + +I cannot see all of the <quote>Blocked</quote> page banner. All I +see is a bright red square. + + There is not enough space to fit the entire page. Try right clicking on the + visible, red portion, and select Show Frame, or equivalent. + This will usually allow you to see the entire Privoxy Blocked + page, and from there you can see just what is being blocked, and why. + + + + +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 + 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. + + + + + + +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. + + + + + + + -Misc +Miscellaneous + + +How much does <application>Privoxy</application> slow my browsing down? This +has to add extra time to browsing. + + It should not slow you down any in real terms, and may actually help + speed things up since ads, banners and other junk are not being displayed. + The actual processing time required by Privoxy + itself for each page, is relatively small in the overall scheme of things, + and happens very quickly. This is typically more than offset by time saved + not downloading and rendering ad images. + -I noticed considerable -delays in page requests compared to the old IJB. What's wrong? + + Filtering via the filterfile + mechanism may cause a perceived slowdown, since the entire page is buffered + before displaying. See below. + + + + + + +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 IJB. Loading pages with large contents +page requests compared to the old Junkbuster. Loading pages with large contents seemed to take forever, then suddenly delivering all the content at once. @@ -540,87 +952,85 @@ 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, the Internet Junkbuster needs to download the entire -page first, do its content magic and then send the page to the browser. +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://i.j.b/"? +What is the "http://p.p/"? -Since JunkBuster sits between your web browser and the Internet, it can be +Since Privoxy sits between your web browser and the Internet, it can be programmed to handle certain pages specially. -With recent versions of JunkBuster (version 2.9.x), you can get some -information about JunkBuster and change some settings by going to -http://i.j.b/ or, equivalently, http://ijbswa.sourceforge.net/config/ -(Note that i.j.b is far easier to type but may not work in some -configurations). +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://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/ or earlier 2.9.x versions). -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 JunkBuster. +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. -If you are not running JunkBuster, then http://i.j.b/ will fail, and -http://ijbswa.sourceforge.net/config/ will return a web page telling you -you're not running JunkBuster. +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. 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). +should really consider upgrading to &p-version;). - + + -Do you still maintain the blocklists? +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. + No. The format of the blocklists has changed significantly in versions + 2.9.x and later. - + -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. - + -How can I hide my IP address? +How can I hide my IP address? - You cannot hide your IP address with Junkbuster or any other software, since + 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. @@ -640,44 +1050,363 @@ You can find a list of anonymous public proxies at multiproxy.org and many more through Google. - + - + - + - + - + + + +Can <application>Privoxy</application> guarantee I am anonymous? + + No. Your chances of remaining anonymous are greatly improved, but unless you + are an expert on Internet security it would be safest to assume that + everything you do on the Web can be traced back to you. + + + Privoxy can remove various information about you, + and allows you more freedom to decide which sites + 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 + as when transferring a file by FTP. Privoxy + does not filter FTP. If you need this feature, or are concerned about the + mail handler of your browser disclosing your email address, you might + consider products such as NSClean. + + + Browsers available only as binaries could use non-standard headers to give + out any information they can have access to: see the manufacturer's license + agreement. It's impossible to anticipate and prevent every breach of privacy + that might occur. The professionally paranoid prefer browsers available as + source code, because anticipating their behavior is easier. Trust the source, + Luke! + - + +Might some things break because header information is +being altered? - -Known Issues - Fillme. + Definitely. More and more sites use HTTP header content to decide what to + display and how to display it. There is many ways that this can be handled, + so having hard and fast rules, is tricky. + + + + 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. + + + + For instance, different browsers use different encodings of Russian and Czech + characters, certain web servers convert pages on-the-fly according to the + User Agent header. Giving a User Agent with the wrong + 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 + 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. + + + + 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. + + + + +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. + + + + + + + + This is not a font problem. The logo is an image that is created by + Privoxy on the fly. So as to not waste + memory, the image is rather small. The blockiness comes when the + image is scaled to fill a largish area. There is not much to be done + about this, other than to use one of the other + imageblock directives: pattern, + blank, or a URL of your choosing. + + +Given the above problem, we have decided to remove the logo option entirely +[as of v2.9.13]. + + + + + +I have large empty spaces 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. + + + + + +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. + + + + + + +<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 + 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 + 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. + + + + + +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. + + + + + +Where can I find more information about <application>Privoxy</application> +and related issues? + + &seealso; + + + + + + -Contact the developers -Please see the user manual for information on how to contact the developers. + + +Troubleshooting + + +I just upgraded and am getting <quote>connection refused</quote> +with every web page? + + Either Privoxy is not running, or your + browser is configured for a different port than what + Privoxy is using. + + + The old Privoxy (and also + Junkbuster) used port 8000 by + 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. + + + + + +I just added a new rule, but the steenkin ad is +still getting through. How? + + If the ad had been displayed before you added its URL, it will probably be + held in the browser's cache for some time, so it will be displayed without + the need for any request to the server, and Privoxy + will not be in the picture. The best thing to do is try flushing the browser's + caches. And then try again. + + + + 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. + + + + + +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. It's probably a good idea to flush the browser cache as well. + + + + 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. 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 a little more detail in the user-manual appendix. + + + + + Alternately, if you are comfortable with a text editor, you can accomplish + the same thing by editing the appropriate actions file. + + + + + +Where can I get help? Report bugs? Feature Requests? Etc? + + Feedback is encouraged, whether good, bad or ugly. Please see the contact + page in the user-manual for + details. + + + + + + +What time is it? + + Time for you to go! + + + + -Copyright and History -Please see the user manual for information on Copyright and History. + + + + Contacting the developers, Bug Reporting and Feature Requests + + &contacting; + + + + + Copyright and History + +Copyright + + ©right; + + +History + + &history; + + + + + + + + + +