Proxomitron

Infobox Software
name = Proxomitron



caption = Proxomitron main screen on Windows XP
developer = Scott R. Lemmon (Deceased)
released =
frequently_updated = yes
programming language =
operating system = Microsoft Windows
language =
genre = Filtering proxy
license = Shonenware
website = [http://www.proxomitron.info/ www.proxomitron.info]

Proxomitron, the Universal Web Filter, is a filtering web proxy written by Scott R. Lemmon. This program was originally designed to run under Windows 95, and all further development of the program was ceased in 2003; even so, Proxomitron is still viable and used on modern Windows platforms such as XP and Vista. The program is generally used to block pop-ups and banners, to remove embedded sounds and animation from web pages, to alter or block JavaScript, and to modify the appearance and content of web pages.

Overview

Properly configured, Proxomitron intercepts HTTP traffic between the user's browser and web servers. The program is capable of altering web page content by removing or adding text. Additionally, it can add, modify, or delete HTTP message headers, be configured to block connections or redirect requests based on the web page address, and be configured to route connections through a remote proxy. The user can monitor connections and filter activations, if desired.

Program operation is dictated through the use of a configuration file containing specialized filters which can be written, edited, deleted, enabled or disabled by the user via the program's graphical user interface. (Third-party filters can also be imported, or "merged," into the configuration.) The filters utilize a "matching" language similar to the standard regular expressions used in text editing. Additional files, such as "blocklists" and SSL DLLs, can extend filtering capabilities.

Use of the program requires knowledge of the Proxomitron scripting language, as well as some familiarity with at least one of HTTP, HTML, JavaScript, and CSS. The scripting interface was not designed to be user-friendly. Because of these complications, the program can be difficult to customise for novice or non-technical users. A default set of filters is included with the program; advanced filters and filter sets written by experienced users are also available online. (See external links.)

Features

The following items are the basic applications and features of the program. [Scott R Lemmon, [http://www.proxomitron.info/45/help/Intro.html Proxomitron Help Files] , Proxomitron. Info]
* Filter page content: Using the scripting language, filters are prepared with editing commands to match and replace text in the downloaded page. Specific pages can be targeted for filtering by matching the page's URL with a specified pattern.

* Filter HTTP headers: Separate filters for incoming and outgoing HTTP headers can be used to modify the values of existing headers, add new headers, or delete headers. One example of such usage would be for cookie management.

* Variables: Filters can use local variables (per filter) or global variables (available to all filters per request) to capture/store text for further test matching, to reinsert content into a new location, or to write content to lists. Preset variables are also available, e.g., the page's URL.

* Special commands: A number of special commands are available for use by filters or in URLs; e.g., a filter-based command can check if the user presses a particular key, or a URL-embedded command can direct Proxomitron to filter a local file.

* Create lists for filters: Text files (known as "blocklists") can be used as sources for patterns for filter matches.

* Create standard lists: Text files (known as "logfiles") can be used by filters to append captured data to a list.

* Create session lists: Memory-only text files can be generated and used by filters to build temporary blocklists, or permanent blocklists can be configured to only allow filters to add memory-only "session" data.

* Insert files: Local text files containing plain text, HTML snippits, css, or scripts can be independently retrieved and written into the web page by filters.

* Reroute traffic: Filters can redirect requests to different web pages or to local files, either by sending the new location as a directive to the browser or by "transparently" connecting to the new location directly.

* View traffic between server and browser: The log window permits the user to see the HTTP traffic between the browser and server. This can (optionally) include any POSTed data.

* Provide alerts: Filters can be configured to have Proxomitron generate its own alert or confirmation popup containing user-supplied text.

* Uncompress data on the fly: With the ZLIB library, the Proxomitron can uncompress GZIP compressed data streams and filter pages delivered in compressed modes.

* Filter "secure" channels: With libraries to provide the SSL routines, the Proxomitron can filter secure, encoded streams. Since this forces the proxy to act as a "man in the middle," this should not be used in most cases.

* Chain to remote proxies: Proxomitron can test remote proxies, maintain a list of proxies to utilize, and be configured to rotate the remote proxy connections.

* Run program or URL: Proxomitron can be configured to launch an external program or URL (as specified in the program settings) upon startup, or on demand via the Launch icon or a menu option. Launching programs and URLs from filters can also be accomplished through the use of an undocumented $EXEC command. [Mona Oliver, [http://mizzmona.com/proxomitron/notes/ Proxomitron Notes, Exec Command] MizzMona.com]

* Change interface textures: The user can select bitmap images (referred to as "textures") for tiling interface backgrounds as well as button and tab faces, or simply disable this feature. An internal set of default bitmaps (admittedly "psychedelic" [Scott R Lemmon, [http://www.proxomitron.info/45/help/Disorientation.html Proxomitron Help Files, Disorientation] , Proxomitron. Info] ) are included with the program.

* Debug: A special viewing of the page source showing which filters matched what page content can be sent to the browser for debugging purposes. A test window is also available from the filter editor dialogs for testing matches and checking filter efficiency.

History

The first public release of Proxomitron (Naoko 2) was in 1999 [Scott R. Lemmon, [http://groups.google.com/group/comp.archives.ms-windows.announce/msg/baffeefacc9b5000/ "proxn2i.zip - Proxomitron: Custom filter webpages as viewed"] , "Usenet", 1999-03-23] as a download via Simtel. The program was distributed under a "ShonenWare" license; it was free to use, but if the user purchased a Shonen Knife CD and convinced Lemmon that he or she had listened to it, then Lemmon would consider that to be sufficient to register that user.

Releases that followed were all named "Naoko" (for Naoko Yamano) followed by a release number. (Release versions were 3, 3(b), 4.0, 4.1, 4.2, 4.3, 4.4, 4.5.)

The May 2003 release of Naoko 4.5 was followed very quickly by the removal of the program's web site and Lemmon's declared termination of continued development of Proxomitron. [Iain Cheyne, [http://groups.google.ca/group/alt.comp.freeware/msg/5942408b8aa2f887 "The message from Scott"] , "Usenet", 2003-06-02] A subsequent release, however, was made in June 2003, primarily to revert a new behavior related to remote proxy connections that had been designed into the May version. [Anon. [http://www.proxomitron.info/files/may-vs-june.html "May vs June changes"] ]

After the release of Naoko 4.5 (June), development was permanently discontinued and the official site had the message:

:消:え:ま:し:た

This reads "kiemashita" in Japanese and translates to "it went out" or "gone." The original home webpage is no longer accessible. Lemmon's mirror redirect was changed to display a different final message from the author a short time later. [Scott R. Lemmon, [http://www.geocities.com/srl_list/ "Now that's what I call a dead Proxomitron!"] ]

The author, Scott R. Lemmon, died 1 May 2004 at the age of 36. [Paul Laudanski, [http://www.castlecops.com/article-5228-nested-0-0.html "Scott Lemmon, Proxomitron Author, Deceased May 1st 2004"] , "CastleCops", 2004-07-16]

Current status

As this was a closed-source project, Proxomitron is no longer being maintained nor developed; however, the Proxomitron program is still functional, and there is a community of users who provide support for it through electronic forums. Filters, filter sets, compatible DLLs and other files, as well as GUI patches to restyle and/or update Proxomitron's graphical user interface, are also being provided by users. (See external links.)

Many current browsers do contain features similar to those provided by Proxomitron filters - blocking advertisements and pop-ups, for example. Other browser features or add-ons, such as Greasemonkey for Firefox and user stylesheets/scripts for Opera, also allow for local modification of web pages.

See also

* [http://proximodo.sourceforge.net/ Proximodo] , inspired by- and interoperable with proxomitron
*AlchemyPoint
*Privoxy
*Greasemonkey
*iMacros
*Internet Junkbuster [http://internet.junkbuster.com/ GPL text mode only local proxy]
*Wwwoffle [http://www.gedanken.demon.co.uk/wwwoffle/ Open source proxy]

External links

Distribution and resources

* [http://proxomitron.info/ Proxomitron.Info] : Main program distribution site and ongoing information/resource project
* [http://www.buerschgens.de/Prox/ Der Proxomitron] : German Proxomitron program distribution and resources
* [http://www.pluto.dti.ne.jp/~tengu/proxomitron/ Proxomitron-J] : Japanese Proxomitron program distribution and resources
* [http://proxomitron.ru/ Proxomitron.ru] : Russian Proxomitron resource, discussion forum and pack with modern filters

Support

* [http://groups.yahoo.com/group/prox-list/ YahooGroups Prox-List] : The original discussion group, includes message archives, files section
* [http://castlecops.com/c14-Proxomitron.html Active forums at Castlecops]
* [http://prxbx.com/forums/ The Un-Official Proxomitron Forum]

Filter sets

* [http://www.geocities.com/sidki3003/prox.html Sidki] : Advanced filter set, SSL files, proxcert generator
* [http://www.castlecops.com/t124920-About_Grypens_Filter_Set.html Grypen] : Advanced filter set (successor of JD5000 set)

Graphical user interface patches

* [http://www.xs4all.nl/~vsetten/prox/ ProxoPatcher] : Henk's GUI patch for Proxomitron 4.5-J
* [http://mizzmona.com/proxomitron/gui/ PtronGUI] : MizzMona's GUI patch for Proxomitron 4.5-J
* [http://www.geocities.com/sidki3003/prox-gui.html ProxPatch] Sidki's GUI patch for Proxomitron 4.5-J

Other

* [http://homepage.usask.ca/~ijm451/prox/ Proxomitron history and archive]
* [http://www.g4tv.com/callforhelparchive/features/44473/Free_File_Proxomitron.html Proxomitron on TechTV] : TechTV's video

References