How much of an impact depends on many things, including the CPU of the host system, how aggressive the configuration is, which specific actions are being triggered, the size of the page, the bandwidth of the connection, etc.
-Overall, 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 typically being retrieved and displayed. The actual processing time @@ -72,7 +49,6 @@ body { very quickly. This is typically more than offset by time saved not downloading and rendering ad images and other junk content (if ad blocking is being used).
-"Filtering" content via the filter or
-
Also, when filtering is enabled but zlib support isn't available,
compression is often disabled (see
If you use any filter action, such as filtering banners by size, web-bugs etc, or the @@ -104,7 +77,6 @@ body { "_top">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 typically does not really change much 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 @@ -113,7 +85,6 @@ body { page where there is filtering being done. But overall, the difference should be very minimal. If there is a big impact, then probably some other situation is contributing (like anti-virus software).
-Filtering is automatically disabled for inappropriate MIME types. But note that if the web server mis-reports the MIME type, then content that should not be filtered, could be.
http://config.privoxy.org/ is the address of Privoxy's built-in user interface, and http://p.p/ is a shortcut for it.
-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".
-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 @@ -143,22 +110,23 @@ body { 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.
+ intercepted, and you have accessed the real web site at config.privoxy.org. +Note that config.privoxy.org resolves to a public IP address. If you + use config.privoxy.org as ping or traceroute target you will reach the + system on the Internet (Privoxy can't intercept ICMP requests). If you + want to ping the system Privoxy runs on, you should use its IP address + or local DNS name (if it has got one).
Please see the Contact section for various ways to interact with the developers.
Whether such submissions are eventually included in the default.action configuration file depends on how significant the issue is. We of course want to address any potential @@ -171,11 +139,9 @@ body { user's user.action, and thus would be unlikely to be included.
Rest assured that it has been read and considered. Why it is not answered, could be for various reasons, including no one has a good answer for it, no one has had time to yet investigate it thoroughly, it @@ -183,21 +149,17 @@ body { information was provided to help us help you. Your efforts are not wasted, and we do appreciate them.
If you run both the browser and Privoxy locally, you cannot hide your IP address with Privoxy or ultimately any other software alone. The server needs to know your IP address so that it knows where to send the responses back.
-There are many publicly usable "anonymous" proxies out there, which provide a further level of indirection between you and the web server.
-However, these proxies are called "anonymous" because you don't need to authenticate, not because they would offer any real anonymity. Most of them will log your IP address and make it available to the @@ -205,7 +167,6 @@ body { fact you can't even rule out that some of them only exist to *collect* information on (those suspicious) people with a more than average preference for privacy.
-If you want to hide your IP address from most adversaries, you should consider chaining Privoxy with Tor. The @@ -213,28 +174,24 @@ body { do I use Privoxy together with Tor section just below.
No. Your chances of remaining anonymous are improved, but unless you chain Privoxy with Tor or a similar proxy and know what you're doing when it comes to configuring the rest of your system, you should 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 neither - hides your IP address, nor can it guarantee that the rest of the system - behaves correctly. There are several possibilities how a web sites can - find out who you are, even if you are using a strict you more freedom to decide which sites you can + trust, and what details you want to reveal. But it neither hides your + IP address, nor can it guarantee that the rest of the system behaves + correctly. There are several possibilities how a web sites can find out + who you are, even if you are using a strict Privoxy configuration and chained it with Tor.
-Most of Privoxy's privacy-enhancing features can be easily subverted by an insecure browser configuration, therefore you should use a browser that can be configured to only @@ -243,14 +200,12 @@ body { "APPLICATION">Privoxy modify the User-Agent header, if websites can get all the information they want through JavaScript, ActiveX, Flash, Java etc.
-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 @@ -258,19 +213,15 @@ body { paranoid prefer browsers available as source code, because anticipating their behavior is easier. Trust the source, Luke!
Good! Actually, they are probably testing for some other kinds of proxies. Hiding yourself completely would require additional steps.
Before you configure Privoxy to use Tor, please follow the User Manual chapters 5. Startup to make sure Privoxy itself is setup correctly.
-If it is, refer to Tor's extensive documentation to learn how to install Tor's logfile says that "Tor has successfully opened a circuit" and it "looks like client functionality is working".
-If either Tor or Privoxy isn't working, their combination most likely will neither. Testing them on their own will also help you to @@ -295,7 +244,6 @@ body { Tor developers. If Tor isn't working, don't send bug reports to the Privoxy Team.
-If you verified that Privoxy and Tor are working, it is time to connect them. As far as Privoxy is concerned, @@ -306,8 +254,7 @@ body { done through Tor and thus invisible to your local network. Using socks4a would work too, but with socks5 you get more precise error messages.
- -Since Privoxy 3.0.5, its Privoxy's main configuration file is already prepared for Tor, if you are using a default Tor configuration @@ -315,86 +262,74 @@ body { "APPLICATION">Privoxy, you just have to edit the forwarding section and uncomment the line:
- -
-# forward-socks5 / 127.0.0.1:9050 . - -+ # forward-socks5t / 127.0.0.1:9050 . + |
Note that if you got Tor through one of the bundles, you may have to + change the port from 9050 to 9150 (or even another one). For details, + please check the documentation on the Tor website.
This is enough to reach the Internet, but additionally you might want to uncomment the following forward rules, to make sure your local network is still reachable through Privoxy:
- -
- -# forward 192.168.*.*/ . +# forward 192.168.*.*/ . # forward 10.*.*.*/ . # forward 127.*.*.*/ . - -+ |
Unencrypted connections to systems in these address ranges will be as (un)secure as the local network is, but the alternative is that your browser can't reach the network at all. Then again, that may actually be desired and if you don't know for sure that your browser has to be able to reach the local network, there's no reason to allow it.
-If you want your browser to be able to reach servers in your local network by using their names, you will need additional exceptions that look like this:
- -
- -# forward localhost/ . - -+ # forward localhost/ . + |
Save the modified configuration file and open http://config.privoxy.org/show-status/ in your browser, + "_top">http://config.privoxy.org/show-status in your browser, confirm that Privoxy has reloaded its configuration and that there are no other forward lines, unless you know that you need them. If everything looks good, refer to Tor Faq 4.2 to learn how to verify that you are really using Tor.
-Afterward, please take the time to at least skim through the rest of Tor's documentation. Make sure you understand what Tor does, why it is no replacement for application level security, and why you probably don't want to use it for unencrypted logins.
-Definitely. It is common for sites to use browser type, browser version, HTTP header content, and various other techniques in order to dynamically decide what to display and how to display it. What you see, and what I see, might be very different. There are many, many ways that this can be handled, so having hard and fast rules, is tricky.
-The "User-Agent" is sometimes used in this way to identify the browser, and adjust content accordingly.
-Also, different browsers use different encodings of non-English characters, certain web servers convert pages on-the-fly according to the User Agent header. Giving a "User Agent" @@ -410,23 +345,19 @@ body { server. The results of which could inadvertently cause pages to load incorrectly, partially, or even not at all. And there may be no obvious clues as to just what went wrong, or why. Nowhere will there be a - message that says "Turn off fast-redirects - or else! "
- + message that says "Turn off fast-redirects or + else! "Similar thoughts apply to modifying JavaScript, and, to a lesser degree, HTML elements.
-If you have problems with a site, you will have to adjust your configuration accordingly. Cookies are probably the most likely adjustment that may be required, but by no means the only one.
No, it does not have this ability at all. You want something like Squid or in the user manual for details.
Not in the way you mean, or in the way some firewall vendors claim they can. Privoxy can help protect your privacy, but can't protect your system from intrusion attempts. It is, of course, perfectly possible to use both.
+ "emphasis">both.It is technically possible to eliminate banners and ads in a way that frees their allocated page space. This could easily be done by blocking with Privoxy's filters, and - eliminating the entire image - references from the HTML page source.
- + eliminating the entire image references from the HTML page + source.But, this would consume considerably more CPU resources (IOW, slow things down), would likely destroy the layout of some web pages which rely on the banners utilizing a certain amount of page space, and might @@ -466,39 +393,33 @@ body { tables for instance). Also, making ads and banners disappear without any trace complicates troubleshooting, and would sooner or later be problematic.
-The better alternative is to instead let them stay, and block the resulting requests for the banners themselves as is now the case. This leaves either empty space, or the familiar checkerboard pattern.
-So the developers won't support this in the default configuration, but you can of course define appropriate filters yourself to achieve this.
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.
- + secure, there is + little that Privoxy can do but hand + the raw gibberish data though from one end to the other + unprocessed.The only exception to this is blocking by host patterns, as the client needs to tell Privoxy the name of the remote server, so that Privoxy can establish the connection. If that name matches a host-only pattern, the connection will be blocked.
-As far as ad blocking is concerned, this is less of a restriction than it may seem, since ad sources are often identifiable by the host name, and often the banners to be placed in an encrypted page come unencrypted nonetheless for efficiency reasons, which exposes them to the full power of Privoxy's ad blocking.
-"Content cookies" (those that are embedded in the actual HTML or JS page content, see
On Unix-like systems, Privoxy can run as a non-privileged user, which is how we recommend it be run. Also, by default Privoxy 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 @@ -533,30 +451,24 @@ body { external interfaces. ACLs can be defined in addition, and using a firewall is always good too. Better safe than sorry.
Privoxy doesn't have a transparent proxy mode, but you can toggle off blocking and content filtering.
-The easiest way to do that is to point your browser to 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. Note that this is a feature that may need to be enabled in the main config file.
No, this just means all optional filtering and actions are disabled. Privoxy is still acting as a proxy, but just doing less of the things that "middle-man" in the interaction between your browser and web sites. See below to bypass the proxy.
Bypassing a proxy, or proxying based on arbitrary criteria, is purely a browser configuration issue, not a Privoxy issue. Modern browsers typically do have settings for not proxying certain sites. Check your browser's help files.
A "crunch" simply means A "crunch" 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: 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".
-Since version 3.0.7, Privoxy will also log the crunch reason. If you are using an older version you might want to upgrade.
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, and the effects of filtering are there whether the file is simply viewed, or downloaded. And potentially whether the @@ -619,9 +523,8 @@ body { "good" content that we do want. Privoxy is blind to the differences, and can only distinguish "good from bad" by the - configuration parameters we - give it.
- + configuration parameters we give it.Privoxy knows the differences in files according to the "Content Type" as reported by the webserver. If this is reported accurately (e.g. @@ -635,20 +538,17 @@ body { 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 rare) cases.
-Note that versions later than 3.0.2 do NOT filter document types reported as "text/plain". Prior to this, Privoxy did filter this document type.
-In short, filtering is "ON" if a) the content type as reported by the webserver is appropriate and b) the configuration allows it (or at - least does not disallow it). That's it. There is no magic cookie - anywhere to say this is "good" and this is - "bad". It's the configuration that lets it - all happen or not.
- + "emphasis">and b) the configuration + allows it (or at least does not disallow it). That's it. There is no + magic cookie anywhere to say this is "good" + and this is "bad". It's the configuration + that lets it all happen or not.If you download text files, you probably do not want these to be filtered, particularly if the content is source code, or other critical content. Source code sometimes might be mistaken for Javascript (i.e. @@ -656,32 +556,27 @@ body { off filtering for download sites (particularly if the content may be plain text files and you are using version 3.0.2 or earlier) in your user.action file. And also, for any site or - page where making any changes - at all to the content is to be avoided.
- + page where making any changes at all to the content is to be + avoided.Privoxy does not do FTP at all, only HTTP and HTTPS (SSL) protocols.
Please read above.
One time-tested technique to defeat common ads is to trick the local DNS system by giving a phony IP address for the ad generator in the local HOSTS file, typically using 127.0.0.1, aka localhost. This effectively blocks the ad.
-There is no reason to use this technique in conjunction with Privoxy. Privoxy does essentially the same thing, much more @@ -693,59 +588,50 @@ body { by Privoxy's configuration, consider adding your list to your user.action file:
- -
-
- { +block }
+
|
Other references and sites of interest to Privoxy users:
-| http://www.privoxy.org/, the https://www.privoxy.org/, the Privoxy Home page. |
| http://www.privoxy.org/faq/, the https://www.privoxy.org/faq/, the Privoxy FAQ. |
| http://www.privoxy.org/developer-manual/, the + | https://www.privoxy.org/developer-manual/, the Privoxy developer manual. |
| http://www.junkbusters.com/ht/en/cookies.html, - an explanation how cookies are used to track web users. | -
| http://www.junkbusters.com/ijb.html, the original - Internet Junkbuster. | -
| http://www.pps.jussieu.fr/~jch/software/polipo/, + "_top">http://www.pps.univ-paris-diderot.fr/~jch/software/polipo/, Polipo is a caching proxy with advanced features like pipelining, multiplexing and caching of partial instances. In many setups it can be used as |
We're not. The text substitutions that you are seeing are disabled in the default configuration as shipped. You have either manually activated the "fun" @@ -855,23 +715,19 @@ body { "QUOTE">"Advanced" profile in the web-based editor. Please upgrade.
Privoxy generates HTML in both its own "templates", and possibly whenever there are text substitutions via a Privoxy filter. While this should always conform to the HTML 4.01 specifications, it has not been validated against this or any other standard.
We didn't. We make Privoxy available for download, but we don't go around installing it on other people's systems behind their back. If you discover Privoxy running on your system and are sure you didn't @@ -879,18 +735,17 @@ body { real Privoxy, but maybe something else that only pretends to be Privoxy, or maybe something that is based on the real Privoxy, but has been modified.
- -Lately there have been reports of problems with some kind of Privoxy - versions that come preinstalled on some Netbooks. Some of the problems - described are inconsistent with the behaviour of official Privoxy - versions, which suggests that the preinstalled software may contain - vendor modifications that we don't know about and thus can't debug.
- +Lately there have been reports of problems with some kind of + "parental control" software based on Privoxy that came preinstalled on + certain ASUS Netbooks. The problems described are inconsistent with + the behaviour of official Privoxy versions, which suggests that the + preinstalled software may contain vendor modifications that we don't + know about and thus can't debug.
Privoxy's license allows vendor modifications, but the vendor has to comply with the license, which involves informing the user about the changes and to make the changes available under the same license as Privoxy itself.
-If you are having trouble with a modified Privoxy version, please try to talk to whoever made the modifications before reporting the problem to us. Please also try to convince whoever made the @@ -899,28 +754,21 @@ body { know.