Copyright © 2001, 2002 by Privoxy Developers
-$Id: faq.sgml,v 1.57 2002/05/05 20:26:02 hal9 Exp $
+$Id: faq.sgml,v 2.2 2002/09/05 04:25:05 hal9 Exp $
-This FAQ gives users and developers alike answers to frequently asked questions
-about Privoxy .
+This FAQ gives quick answers to frequently asked questions about Privoxy. It
+can't and doesn't replace the User Manual.
Privoxy is a web proxy with advanced filtering capabilities for protecting
privacy, filtering web page content, managing cookies, controlling access, and
Privoxy is based on Internet Junkbuster (tm).
-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.
+Please note that this document is constantly evolving. This copy represents the
+state at the release of version 3.1.1. 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.
-------------------------------------------------------------------------------
1.1. What is this new version of Privoxy?
1.2. Why "Privoxy"? Why a name change at all?
1.3. How does Privoxy differ from the old Junkbuster?
- 1.4. What are some of the new features?
- 1.5. What is a "proxy"? How does Privoxy work?
- 1.6. How does Privoxy know what is an ad, and what is not?
- 1.7. Can Privoxy make mistakes? This does not sound very scientific.
- 1.8. My browser does the same things as Privoxy. Why should I use Privoxy
+ 1.4. What is a "proxy"? How does Privoxy work?
+ 1.5. How does Privoxy know what is an ad, and what is not?
+ 1.6. Can Privoxy make mistakes? This does not sound very scientific.
+ 1.7. My browser does the same things as Privoxy. Why should I use Privoxy
at all?
- 1.9. Is there is a license or fee? What about a warranty? Registration?
- 1.10. I would like to help you, what do I do?
+ 1.8. Is there is a license or fee? What about a warranty? Registration?
+ 1.9. I would like to help you, what do I do?
- 1.10.1. Money Money Money
- 1.10.2. You want to work with us?
+ 1.9.1. Money Money Money
+ 1.9.2. Software
+ 1.9.3. You want to work with us?
2. Installation
3. Configuration
- 3.1. Can I use my old config files?
- 3.2. What is an "actions" file?
- 3.3. The "actions" concept confuses me. Please list some of these
+ 3.1. Where can I get updated Actions Files?
+ 3.2. Can I use my old config files?
+ 3.3. What is an "actions" file?
+ 3.4. The "actions" concept confuses me. Please list some of these
"actions".
- 3.4. How are actions files configured? What is the easiest way to do this?
- 3.5. There are several different "actions" files. What are the differences?
- 3.6. Why can I change the configuration with a browser? Does that not raise
+ 3.5. How are actions files configured? What is the easiest way to do this?
+ 3.6. There are several different "actions" files. What are the differences?
+ 3.7. How can I make my Yahoo/Hotmail/GMX account work?
+ 3.8. What's the difference between the "Cautious", "Medium" and "Advanced"
+ defaults?
+ 3.9. Why can I change the configuration with a browser? Does that not raise
security issues?
- 3.7. What is "default.filter"?
- 3.8. How can I set up Privoxy to act as a proxy for my LAN?
- 3.9. Instead of ads, now I get a checkerboard pattern. I don't want to see
+ 3.10. What is the default.filter file? What is a "filter"?
+ 3.11. How can I set up Privoxy to act as a proxy for my LAN?
+ 3.12. Instead of ads, now I get a checkerboard pattern. I don't want to see
anything.
- 3.10. Why would anybody want to see a checkerboard pattern?
- 3.11. I see large red banners on some pages that say "Blocked". Why and how
- do I get rid of this?
- 3.12. I cannot see all of the "Blocked" page banner. Help.
- 3.13. Can Privoxy run as a service on Win2K/NT?
- 3.14. How can I make Privoxy work with other proxies like Squid?
- 3.15. Can Privoxy run as a "transparent" proxy?
+ 3.13. Why would anybody want to see a checkerboard pattern?
+ 3.14. I see some images being replaced by a text instead of the
+ checkerboard image. Why and how do I get rid of this?
+ 3.15. Can Privoxy run as a service on Win2K/NT?
+ 3.16. How can I make Privoxy work with other proxies like Squid?
+ 3.17. Can I just set Privoxy to use port 80 and thus avoid individual
+ browser configuration?
+ 3.18. Can Privoxy run as a "transparent" proxy?
4. Miscellaneous
time to browsing.
4.2. I noticed considerable delays in page requests compared to the old
Junkbuster. What's wrong?
- 4.3. What is the "http://p.p/"?
+ 4.3. What are "http://config.privoxy.org/" and "http://p.p/"?
4.4. Do you still maintain the blocklists?
4.5. How can I submit new ads?
4.6. How can I hide my IP address?
4.7. Can Privoxy guarantee I am anonymous?
- 4.8. Might some things break because header information is being altered?
+ 4.8. Might some things break because header information or content is being
+ altered?
4.9. Can Privoxy act as a "caching" proxy to speed up web browsing?
4.10. What about as a firewall? Can Privoxy protect me?
- 4.11. The Privoxy logo that replaces ads is very blocky and ugly looking.
- Can't a better font be used?
- 4.12. I have large empty spaces now where ads used to be. Why?
- 4.13. How can Privoxy filter Secure (HTTPS) URLs?
- 4.14. Privoxy runs as a "server". How secure is it? Do I need to take any
+ 4.11. I have large empty spaces / a checkerboard pattern now where ads used
+ to be. Why?
+ 4.12. How can Privoxy filter Secure (HTTPS) URLs?
+ 4.13. Privoxy runs as a "server". How secure is it? Do I need to take any
special precautions?
- 4.15. How can I temporarily disable Privoxy?
- 4.16. Where can I find more information about Privoxy and related issues?
+ 4.14. How can I temporarily disable Privoxy?
+ 4.15. When "disabled" is Privoxy totally out of the picture?
+ 4.16. My logs show Privoxy "crunches" ads, but also its own CGI pages. What
+ is a "crunch"?
+ 4.17. Can Privoxy effect files that I download from a webserver? FTP
+ server?
+ 4.18. Where can I find more information about Privoxy and related issues?
5. Troubleshooting
5.2. I just added a new rule, but the steenkin ad is still getting through.
How?
5.3. One of my favorite sites does not work with Privoxy. What can I do?
+ 5.4. After installing Privoxy, I have to log in every time I start IE. What
+ gives?
+ 5.5. I cannot connect to any FTP sites. Privoxy seems to be blocking me.
+ 5.6. In Mac OSX, I can't configure Microsoft Internet Explorer to use
+ Privoxy as the HTTP proxy.
+ 5.7. In Mac OSX, I dragged the Privoxy folder to the trash in order to
+ uninstall it. Now the finder tells me I don't have sufficient
+ privileges to empty the trash.
+ 5.8. I get a completely blank page at one site. "View Source" shows only:
+ <html><body></body></html>.
6. Contacting the developers, Bug Reporting and Feature Requests
6.1. Get Support
- 6.2. Report bugs
- 6.3. Request new features
- 6.4. Report ads or other filter problems
+ 6.2. Report Bugs
+ 6.3. Request New Features
+ 6.4. Report Ads or Other Actions-Related Problems
6.5. Other
7. Privoxy Copyright, License and History
1.1. What is this new version of Privoxy?
-The original Internet JunkbusterTM (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.
+In the beginning, there was the Internet Junkbuster, by Anonymous Coders and
+Junkbusters Corporation. It saved many users a lot of pain in the early days of
+web advertising and user tracking.
-Privoxy has evolved from the Junkbuster 2.0.2 code base, and has advanced
-significantly at this point.
+But the web, its protocols and standards, and with it, the techniques for
+forcing users to consume ads, give up autonomy over their browsing, and for
+spying on them, kept evolving. Unfortunately, the Internet Junkbuster did not.
+Version 2.0.2, published in 1998, was (and is) the last official release
+available from Junkbusters Corporation. Fortunately, it had been released under
+the GNU GPL, which allowed further development by others.
-Please see the History section for more information on the history of
-Junkbuster and Privoxy.
+So Stefan Waldherr started maintaining an improved version of the software, to
+which eventually a number of people contributed patches. It could already
+replace banners with a transparent image, and had a first version of pop-up
+killing, but it was still very closely based on the original, with all its
+limitations, such as the lack of HTTP/1.1 support, flexible per-site
+configuration, or content modification. The last release from this effort was
+version 2.0.2-10, published in 2000.
+
+Then, some developers picked up the thread, and started turning the software
+inside out, upside down, and then reassembled it, adding many new features
+along the way.
+
+The result of this is Privoxy, whose first stable release, 3.0, was released
+August, 2002.
-------------------------------------------------------------------------------
1.2. Why "Privoxy"? Why a name change at all?
-Privoxy is the "Privacy Enhancing Proxy".
+Privoxy is the "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 Privoxy project itself, and they, in fact,
-still share our ideals and goals.)
+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
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.
+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.
--------------------------------------------------------------------------------
-
-1.4. What are some of the new features?
+Privoxy's new features include:
* Integrated browser based configuration and control utility at http://
config.privoxy.org/ (shortcut: http://p.p/). Browser-based tracing of rule
* Modularized configuration that allows for standard settings and user
settings to reside in separate files, so that installing updated actions
- files won't overwrite idividual user settings.
+ files won't overwrite individual user settings.
* HTTP/1.1 compliant (but not all optional 1.1 features are supported).
-------------------------------------------------------------------------------
-1.5. What is a "proxy"? How does Privoxy work?
+1.4. What is a "proxy"? How does Privoxy 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.
-------------------------------------------------------------------------------
-1.6. How does Privoxy know what is an ad, and what is not?
+1.5. How does Privoxy know what is an ad, and what is not?
+
+Privoxy's approach to blocking ads is twofold:
-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.
+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.
-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.
+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.
-------------------------------------------------------------------------------
-1.7. Can Privoxy make mistakes? This does not sound very scientific.
+1.6. Can Privoxy 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.
+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
-------------------------------------------------------------------------------
-1.8. My browser does the same things as Privoxy. Why should I use Privoxy at
+1.7. My browser does the same things as Privoxy. Why should I use Privoxy at
all?
Modern browsers do indeed have some of the same functionality as Privoxy. Maybe
-------------------------------------------------------------------------------
-1.9. Is there is a license or fee? What about a warranty? Registration?
+1.8. 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.
-------------------------------------------------------------------------------
-1.10. I would like to help you, what do I do?
+1.9. I would like to help you, what do I do?
+
+1.9.1. Money Money Money
+
+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.
+
+-------------------------------------------------------------------------------
-1.10.1. Money Money Money
+1.9.2. Software
-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.
+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.
-------------------------------------------------------------------------------
-1.10.2. You want to work with us?
+1.9.3. 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.
+Well, helping the team is always a good idea. We welcome new developers,
+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.
2.1. Which browsers are supported by Privoxy?
-Any browser that can be configured to use a "proxy", which should be virtually
+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.
+separate application and talks to the browser in the standardized HTTP
+protocol, just like a web server does.
-------------------------------------------------------------------------------
2.2. Which operating systems are supported?
At present, Privoxy is known to run on Windows(95, 98, ME, 2000, XP), Linux
-(RedHat, Suse, Debian), Mac OSX, OS/2, AmigaOS, FreeBSD, NetBSD, BeOS, and many
-more flavors of Unix.
+(RedHat, SuSE, Debian, Conectiva, Gentoo, Slackware), Mac OSX, OS/2, AmigaOS,
+BeOS, FreeBSD, NetBSD, Solaris, and more flavors of Unix.
But any operating system that runs TCP/IP, can conceivably take advantage of
Privoxy in a networked situation where Privoxy would run as a server on a LAN
gateway. Then only the "gateway" needs to be running one of the above operating
systems.
-Source code is freely available, so porting to other operating systems, is
+Source code is freely available, so porting to other operating systems is
always a possibility.
-------------------------------------------------------------------------------
2.3. Can I install Privoxy over Junkbuster?
-We recommend you uninstall Junkbuster first to minimize conflicts and
+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.
+reference. The configuration 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.
-
-Note: Some installers may automatically uninstall Junkbuster, if present!
+Note: Some installers may automatically un-install Junkbuster, if present!
-------------------------------------------------------------------------------
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.
+browser. See below. You should also flush your browser's memory and disk cache
+to get rid of any cached junk items.
-------------------------------------------------------------------------------
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).
+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.
+"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.
+the equivalent hostname. Port assignment would be 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.
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.
+browser is correctly configured by entering the special URL: 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.
-------------------------------------------------------------------------------
3. Configuration
-3.1. Can I use my old config files?
+3.1. Where can I get updated Actions 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.
+Based on your feedback and the continuing development, updated actions files
+will be made available on the files section of our project page.
--------------------------------------------------------------------------------
+If you wish to receive an email notification whenever we release updates of
+Privoxy or the actions file, subscribe to our announce mailing list,
+ijbswa-announce@lists.sourceforge.net.
-3.2. What is an "actions" 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.
+3.2. Can I use my old config files?
-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.
+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.
-------------------------------------------------------------------------------
-3.3. The "actions" concept confuses me. Please list some of these "actions".
+3.3. What is an "actions" file?
-These are all explained in the user-manual. Please refer to that.
+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 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
-------------------------------------------------------------------------------
-3.4. How are actions files configured? What is the easiest way to do this?
+3.4. The "actions" concept confuses me. Please list some of these "actions".
+
+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.
-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.
+-------------------------------------------------------------------------------
+
+3.5. How are actions files configured? What is the easiest way to do this?
-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. But probably the 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.
-------------------------------------------------------------------------------
-3.5. There are several different "actions" files. What are the differences?
+3.6. There are several different "actions" files. What are 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 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.
+
+-------------------------------------------------------------------------------
-Earlier versions included three different versions default.action files. The
-new scheme allows for greater flexibility of local configuration, and for
-browser based configuration.
+3.7. How can I make my Yahoo/Hotmail/GMX account work?
+
+The default configuration shouldn't impact the usability of any of these
+services. It will, however, make all cookies temporary, so that your browser
+will forget your login credentials in between browser sessions. If you would
+like not to have to log in manually each time you access those websites, simply
+turn off all cookie handling for them in the user.action file. An example for
+yahoo might look like:
+
+# Allow all cookies for Yahoo login:
+#
+{ -crunch-incoming-cookies -crunch-outgoing-cookies -session-cookies-only }
+.login.yahoo.com
+
+-------------------------------------------------------------------------------
+
+3.8. What's the difference between the "Cautious", "Medium" and "Advanced"
+defaults?
+
+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:
+
+Table 1. Default Configurations
+
++-----------------------------------------------------------------------------+
+|Feature |Cautious |Intermadiate |Advanced |
+|-------------------+------------------+-------------------+------------------|
+|Ad-blocking by URL |yes |yes |yes |
+|-------------------+------------------+-------------------+------------------|
+|Ad-filtering by |yes |yes |yes |
+|size | | | |
+|-------------------+------------------+-------------------+------------------|
+|GIF de-animation |no |yes |yes |
+|-------------------+------------------+-------------------+------------------|
+|Referer forging |no |yes |yes |
+|-------------------+------------------+-------------------+------------------|
+|Cookie handling |none |session-only |kill |
+|-------------------+------------------+-------------------+------------------|
+|Pop-up killing |no |yes |yes |
+|-------------------+------------------+-------------------+------------------|
+|Fast redirects |no |no |yes |
+|-------------------+------------------+-------------------+------------------|
+|HTML taming |yes |yes |yes |
+|-------------------+------------------+-------------------+------------------|
+|JavaScript taming |yes |yes |yes |
+|-------------------+------------------+-------------------+------------------|
+|Web-bug killing |yes |yes |yes |
+|-------------------+------------------+-------------------+------------------|
+|Fun text |no |no |yes |
+|replacements | | | |
+|-------------------+------------------+-------------------+------------------|
+|Image tag |no |no |yes |
+|reordering | | | |
+|-------------------+------------------+-------------------+------------------|
+|Ad-filtering by |no |no |yes |
+|link | | | |
++-----------------------------------------------------------------------------+
+
+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.
-------------------------------------------------------------------------------
-3.6. Why can I change the configuration with a browser? Does that not raise
+3.9. 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.
-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.
-------------------------------------------------------------------------------
-3.7. What is "default.filter"?
+3.10. What is the default.filter file? What is a "filter"?
-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.
+The default.filter file is where filters are defined, which can be used to
+modify or remove, web page content on the fly. Filters apply 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 in one of the actions files. Filtering is
+automatically disabled for inappropriate MIME types.
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.
+provided default.filter with a text editor and define your own filters. This is
+potentially a very powerful feature, but requires some expertise in both
+regular expressions and HTML/HTTP.
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.
-------------------------------------------------------------------------------
-3.8. How can I set up Privoxy to act as a proxy for my LAN?
+3.11. How can I set up Privoxy 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:
+By default, Privoxy only responds to requests 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 should look
+like:
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.
+If you run Privoxy on a LAN with untrusted users, we recommend that you
+double-check the access control and security options!
+
-------------------------------------------------------------------------------
-3.9. Instead of ads, now I get a checkerboard pattern. I don't want to see
+3.12. 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.
-------------------------------------------------------------------------------
-3.10. Why would anybody want to see a checkerboard pattern?
+3.13. 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..
-------------------------------------------------------------------------------
-3.11. I see large red banners on some pages that say "Blocked". Why and how do
-I get rid of this?
+3.14. 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 explicitly as "images" (e.g. ads that are GIF image files).
-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.
+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.
-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 aribitrary
-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. Such
-situations can be a little trickier to deal with, and Privoxy may show the
-"Blocked" page, despite your best efforts.
+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 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 "+set-image-blocker" action handle the ad
-that is embedded in the frame's HTML page.
+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.
-------------------------------------------------------------------------------
-3.12. I cannot see all of the "Blocked" page banner. Help.
+3.15. Can Privoxy run as a service on Win2K/NT?
-There is not enough available space to fit the entire Blocked page. Try right
-clicking on the visible 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.
+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 :(
-As of Privoxy 2.9.14, the Blocked banner page is re-sizeable, and tries to
-adjust to the allotted space. There may be occassions where there just isn't
-enough room to display much of anything useful though.
+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.
-------------------------------------------------------------------------------
-3.13. Can Privoxy 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 :(
+3.16. How can I make Privoxy work with other proxies like Squid?
-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.
+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.
-------------------------------------------------------------------------------
-3.14. How can I make Privoxy work with other proxies like Squid?
+3.17. Can I just set Privoxy to use port 80 and thus avoid individual browser
+configuration?
-This can be done. See the user manual, which describes how to do this.
+No, its more complicated than that. This only works with special kinds of
+proxies known as "transparent" proxies (see below).
-------------------------------------------------------------------------------
-3.15. Can Privoxy run as a "transparent" proxy?
+3.18. Can Privoxy run as a "transparent" 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 with another proxy that has this ability should work though.
-See the user manual, which describes this, and also http://
-www.transproxy.nlc.net.au/.
+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/).
-------------------------------------------------------------------------------
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.
-"Filtering" via the filterfile mechanism may cause a perceived slowdown, since
-the entire page is buffered before displaying. See below.
+"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.
-------------------------------------------------------------------------------
4.2. 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
+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".
+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.
+Filtering is automatically disabled for inappropriate MIME types.
-------------------------------------------------------------------------------
-4.3. What is the "http://p.p/"?
+4.3. 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 2.9.15).
+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
+3.1.1.
-------------------------------------------------------------------------------
4.4. 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 ...
-------------------------------------------------------------------------------
4.5. 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.
-------------------------------------------------------------------------------
4.6. 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.
+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
(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.
+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.
-------------------------------------------------------------------------------
-------------------------------------------------------------------------------
-4.8. Might some things break because header information is being altered?
+4.8. 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
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.
+"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.
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
+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.
+server when no "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
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.
+proxies like Squid. See the forwarding chapter in the user manual for details.
-------------------------------------------------------------------------------
4.10. What about as a firewall? Can Privoxy 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.
-------------------------------------------------------------------------------
-4.11. The Privoxy logo that replaces ads is very blocky and ugly looking. Can't
-a better font be used?
+4.11. I have large empty spaces / a checkerboard pattern now where ads used to
+be. Why?
-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.
+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.
-Given the above problem, we have decided to remove the logo option entirely [as
-of v2.9.13].
+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.
-4.12. 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.
+4.12. How can Privoxy filter Secure (HTTPS) URLs?
--------------------------------------------------------------------------------
+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.
-4.13. How can Privoxy filter Secure (HTTPS) URLs?
+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.
-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.
+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.
-------------------------------------------------------------------------------
-4.14. Privoxy runs as a "server". How secure is it? Do I need to take any
+4.13. Privoxy runs as a "server". 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,
+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 Privoxy is not itself directly exposed to the Internet in this
+Also, by default Privoxy only listens to requests 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.
+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.
-------------------------------------------------------------------------------
-4.15. How can I temporarily disable Privoxy?
+4.14. How can I temporarily disable Privoxy?
-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.
+The easiest way is to access Privoxy with your browser by using the remote
+toggle URL: http://config.privoxy.org/toggle. See the Bookmarklets section of
+the User Manual for an easy way to access this feature.
-------------------------------------------------------------------------------
-4.16. Where can I find more information about Privoxy and related issues?
+4.15. When "disabled" is Privoxy totally out of the picture?
+
+No, this just means all filtering and actions are disabled. Privoxy is still
+acting as a proxy, but just not doing any of the things that Privoxy would
+normally be expected to do. It is still a "middle-man" in the interaction
+between your browser and web sites.
+
+-------------------------------------------------------------------------------
+
+4.16. My logs show Privoxy "crunches" ads, but also its own CGI pages. What is
+a "crunch"?
+
+A "crunch" simply means Privoxy intercepted something, nothing more. Often this
+is indeed ads or banners, but Privoxy uses the same mechanism for trapping
+requests for its own internal pages. For instance, a request for Privoxy's
+configuration page at: http://config.privoxy.org, is intercepted (i.e. it does
+not go out to the 'net), and the familiar CGI configuration is returned to the
+browser, and the log consequently will show a "crunch".
+
+-------------------------------------------------------------------------------
+
+4.17. Can Privoxy effect files that I download from a webserver? FTP server?
+
+From the webserver's perspective, there is no difference between viewing a
+document (i.e. a page), and downloading a file. The same is true of Privoxy. If
+there is a match for a block pattern, it will still be blocked, and of course
+this is obvious. Filtering is potentially more of a concern since the results
+are not always so obvious.
+
+Privoxy knows the differences in files according to the "Document Type" as
+reported by the webserver. If this is reported accurately (e.g. "application/
+zip" for a zip archive), then Privoxy knows to ignore these where appropriate.
+It is possible, however, that documents that are of an unknown type (generally
+assumed to be "text/plain") will be filtered, as will those that might be
+incorrectly reported by the webserver. If such a file is a downloaded file that
+is intended to be saved to disk, then any content that might have been altered
+by filtering, will be saved too, for these (probably very rare) cases.
+
+Privoxy does not do FTP at all, only HTTP protocols.
+
+-------------------------------------------------------------------------------
+
+4.18. Where can I find more information about Privoxy and related issues?
Other references and sites of interest to Privoxy users:
-http://www.privoxy.org/, The Privoxy Home page.
+http://www.privoxy.org/, the Privoxy Home page.
-http://sourceforge.net/projects/ijbswa, the Project Page for Privoxy on
-Sourceforge.
+http://www.privoxy.org/faq/, the Privoxy FAQ.
-http://p.p/, access Privoxy from your browser. Alternately, http://
-config.privoxy.org may work in some situations where the first does not.
+http://sourceforge.net/projects/ijbswa/, the Project Page for Privoxy on
+SourceForge.
-http://p.p/, and select "Privoxy - Submit Filter Feedback" to submit "misses"
-to the developers.
+http://config.privoxy.org/, the web-based user interface. Privoxy must be
+running for this to work. Shortcut: http://p.p/
-http://www.junkbusters.com/ht/en/cookies.html
+http://www.privoxy.org/actions/, to submit "misses" to the developers.
-http://www.waldherr.org/junkbuster/
+http://cvs.sourceforge.net/cgi-bin/viewcvs.cgi/ijbswa/contrib/, cool and fun
+ideas from Privoxy users.
-http://privacy.net/analyze/
+http://www.junkbusters.com/ht/en/cookies.html, an explanation how cookies are
+used to track web users.
-http://www.squid-cache.org/
+http://www.junkbusters.com/ijb.html, the original Internet Junkbuster.
-
+http://www.waldherr.org/junkbuster/, Stefan Waldherr's version of Junkbuster,
+from which Privoxy was derived.
+
+http://privacy.net/analyze/, a useful site to check what information about you
+is leaked while you browse the web.
+
+http://www.squid-cache.org/, a very popular caching proxy, which is often used
+together with Privoxy.
+
+http://www.privoxy.org/developer-manual/, the Privoxy developer manual.
-------------------------------------------------------------------------------
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.
+new port number, or alternately change the listen-address option in Privoxy's
+main configuration file.
-------------------------------------------------------------------------------
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.
+show-url-info and see if it really matches your new rule.
-------------------------------------------------------------------------------
5.3. One of my favorite sites does not work with Privoxy. 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.
+First verify that it is indeed a Privoxy problem, 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 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.
+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,
+
+Troubleshooting actions is discussed in more detail in the user-manual appendix
+. There is also an actions tutorial.
+
+-------------------------------------------------------------------------------
+
+5.4. After installing Privoxy, I have to log in every time I start IE. What
+gives?
+
+This is a quirk that effects the installation of Privoxy, in conjunction with
+Internet Explorer and Internet Connection Sharing on Windows 2000 and Windows
+XP. The symptoms may appear to be corrupted or invalid DUN settings, or
+passwords.
+
+When setting up an NT based Windows system with Privoxy you may find that
+things do not seem to be doing what you expect. When you set your system up you
+will probably have set up Internet Connection Sharing (ICS) with Dial up
+Networking (DUN) when logged in with administrator privileges. You will
+probably have made this DUN connection available to other accounts that you may
+have set-up on your system. E.g. Mum or Dad sets up the system and makes
+accounts suitably configured for the kids.
+
+When setting up Privoxy in this environment you will have to alter the proxy
+set-up of Internet Explorer (IE) for the specific DUN connection on which you
+wish to use Privoxy. When you do this the ICS DUN set-up becomes user specific.
+In this instance you will see no difference if you change the DUN connection
+under the account used to set-up the connection. However when you do this from
+another user you will notice that the DUN connection changes to make available
+to "Me only". You will also find that you have to store the password under each
+different user!
+
+The reason for this is that each user's set-up for IE is user specific. Each
+set-up DUN connection and each LAN connection in IE store the settings for each
+user individually. As such this enforces individual configurations rather than
+common ones. Hence the first time you use a DUN connection after re-booting
+your system it may not perform as you expect, and prompt you for the password.
+Just set and save the password again and all should be OK.
+
+[Thanks to Ray Griffith for this submission.]
+
+-------------------------------------------------------------------------------
+
+5.5. I cannot connect to any FTP sites. Privoxy seems to be blocking me.
+
+Privoxy cannot act as a proxy for FTP traffic, so do not configure your browser
+to use Privoxy as an FTP proxy. The same is true for any protocol other than
+HTTP or HTTPS.
+
+-------------------------------------------------------------------------------
+
+5.6. In Mac OSX, I can't configure Microsoft Internet Explorer to use Privoxy
+as the HTTP proxy.
+
+Microsoft Internet Explorer (in versions like 5.1) respects system-wide network
+settings. In order to change the HTTP proxy, open System Preferences, and click
+on the Network icon. In the settings pane that comes up, click on the Proxies
+tab. Ensure the "Web Proxy (HTTP)" checkbox is checked and enter 127.0.0.1 in
+the entry field. Enter 8118 in the Port field. The next time you start IE, it
+should reflect these values.
+
+-------------------------------------------------------------------------------
+
+5.7. In Mac OSX, I dragged the Privoxy folder to the trash in order to
+uninstall it. Now the finder tells me I don't have sufficient privileges to
+empty the trash.
+
+Just dragging the Privoxy folder to the trash is not enough to delete it.
+Privoxy supplies an uninstall.command file that takes care of these details.
+Open the trash, drag the uninstall.command file out of the trash and
+double-click on it. You will be prompted for confirmation and the
+administration password.
+
+The trash may still appear full after this command; emptying the trash from the
+desktop should make it appear empty again.
+
+-------------------------------------------------------------------------------
+
+5.8. I get a completely blank page at one site. "View Source" shows only:
+<html><body></body></html>.
+
+This is often the result of a webserver using PHP that mishandles the request
+Privoxy sends to not compress the content (a PHP bug).
+
+In a default configuration, Privoxy requests all data be sent "uncompressed".
+This is required for the page filtering and other magic to work. In some rare
+cases, the browser and webserver miscommunicate and the result is a totally
+blank page. The suggested work around is to selectively turn off this feature
+for sites that exhibit such behavior. Example section for user.action:
+
+ # Make exceptions for ill-behaved sites:
+ #
+ {-prevent-compression}
+ .example.com
-------------------------------------------------------------------------------
6. Contacting the developers, Bug Reporting and Feature Requests
-We value your feedback. However, to provide you with the best support, please
-note the following sections.
+We value your feedback. In fact, we rely on it to improve Privoxy and its
+configuration. However, please note the following hints, so we can provide you
+with the best support:
-------------------------------------------------------------------------------
6.1. Get Support
-To get support, use the Sourceforge Support Forum:
+For casual users, our support forum at SourceForge is probably best suited:
+http://sourceforge.net/tracker/?group_id=11118&atid=211118
- http://sourceforge.net/tracker/?group_id=11118&atid=211118
+All users are of course welcome to discuss their issues on the users mailing
+list, where the developers also hang around.
-------------------------------------------------------------------------------
-6.2. Report bugs
+6.2. Report Bugs
-To submit bugs, use the Sourceforge Bug Forum:
+Please report all bugs only through our bug tracker: http://sourceforge.net/
+tracker/?group_id=11118&atid=111118.
- http://sourceforge.net/tracker/?group_id=11118&atid=111118.
+Before doing so, please make sure that the bug has not already been submitted
+and observe the additional hints at the top of the submit form.
-Make sure that the bug has not already been submitted. Please try to verify
-that it is a Privoxy bug, and not a browser or site bug first. If you are using
-your own custom configuration, please try the stock configs to see if the
-problem is a configuration related bug. And if not using the latest development
-snapshot, please try the latest one. Or even better, CVS sources. Please be
-sure to include the Privoxy version, platform, browser, any pertinent log data,
-any other relevant details (please be specific) and, if possible, some way to
-reproduce the bug.
+Please try to verify that it is a Privoxy bug, and not a browser or site bug
+first. If unsure, try toggling off Privoxy, and see if the problem persists.
+The appendix of the user manual also has helpful information on action
+debugging. If you are using your own custom configuration, please try the stock
+configs to see if the problem is configuration related.
--------------------------------------------------------------------------------
+If not using the latest version, chances are that the bug has been found and
+fixed in the meantime. We would appreciate if you could take the time to
+upgrade to the latest version (or even the latest CVS snapshot) and verify your
+bug, but this is not required for reporting.
-6.3. Request new features
+-------------------------------------------------------------------------------
-To submit ideas on new features, use the Sourceforge feature request forum:
+6.3. Request New Features
- http://sourceforge.net/tracker/?atid=361118&group_id=11118&func=browse.
+You are welcome to submit ideas on new features or other proposals for
+improvement through our feature request tracker at http://sourceforge.net/
+tracker/?atid=361118&group_id=11118.
-------------------------------------------------------------------------------
-6.4. Report ads or other filter problems
+6.4. Report Ads or Other Actions-Related Problems
-You can also send feedback on websites that Privoxy has problems with. Please
-bookmark the following link: "Privoxy - Submit Filter Feedback". Once you surf
-to a page with problems, use the bookmark to send us feedback. We will look
-into the issue as soon as possible.
+Please send feedback on ads that slipped through, innocent images that were
+blocked, and any other problems relating to the default.action file through our
+actions feedback mechanism located at http://www.privoxy.org/actions/. On this
+page, you will also find a bookmark which will take you back there from any
+troubled site and even pre-fill the form!
New, improved default.action files will occasionally be made available based on
-your feedback. These will be announced on the ijbswa-announce list.
+your feedback. These will be announced on the ijbswa-announce list and
+available from our the files section of our project page.
-------------------------------------------------------------------------------
6.5. Other
-For any other issues, feel free to use the mailing lists:
-
- http://sourceforge.net/mail/?group_id=11118.
-
-Anyone interested in actively participating in development and related
-discussions can also join the appropriate mailing list. Archives are available,
-too. See the page on Sourceforge.
+For any other issues, feel free to use the mailing lists. Technically
+interested users and people who wish to contribute to the project are also
+welcome on the developers list! You can find an overview of all Privoxy-related
+mailing lists, including list archives, at: http://sourceforge.net/mail/?
+group_id=11118.
-------------------------------------------------------------------------------
7.2. History
-Privoxy is evolved, and derived from, the Internet Junkbuster, with many
-improvments and enhancements over the original.
-
-Junkbuster was originally written by Anonymous Coders and Junkbusters
-Corporation, and was released as free open-source software under the GNU GPL.
-Stefan Waldherr made many improvements, and started the SourceForge project
-Privoxy to rekindle development. There are now several active developers
-contributing. The last stable release of Junkbuster was v2.0.2, which has now
-grown whiskers ;-).
+In the beginning, there was the Internet Junkbuster, by Anonymous Coders and
+Junkbusters Corporation. It saved many users a lot of pain in the early days of
+web advertising and user tracking.
+
+But the web, its protocols and standards, and with it, the techniques for
+forcing users to consume ads, give up autonomy over their browsing, and for
+spying on them, kept evolving. Unfortunately, the Internet Junkbuster did not.
+Version 2.0.2, published in 1998, was (and is) the last official release
+available from Junkbusters Corporation. Fortunately, it had been released under
+the GNU GPL, which allowed further development by others.
+
+So Stefan Waldherr started maintaining an improved version of the software, to
+which eventually a number of people contributed patches. It could already
+replace banners with a transparent image, and had a first version of pop-up
+killing, but it was still very closely based on the original, with all its
+limitations, such as the lack of HTTP/1.1 support, flexible per-site
+configuration, or content modification. The last release from this effort was
+version 2.0.2-10, published in 2000.
+
+Then, some developers picked up the thread, and started turning the software
+inside out, upside down, and then reassembled it, adding many new features
+along the way.
+
+The result of this is Privoxy, whose first stable release, 3.0, was released
+August, 2002.
projects / privoxy.git / blobdiff