Muffin version 0.2 What is Muffin? Muffin is an HTTP proxy filter that sits between your web browser and your HTTP proxy server. All HTTP transactions are passed through Muffin which uses filter modules written in Java to process and possibly modify each transaction. Several example filters are included with Muffin, but users are encouraged to write their own. Muffin is not an applet, it is a stand-alone Java application.

Muffin is written in Java which means it requires the Java run-time environment to be installed your system. One place to obtain Java is from www.javasoft.com.

I've tested Muffin with the JavaSoft JDK 1.0.2 on Solaris 2.5 and Windows 95. Java works on the Macintosh, but the JDK 1.0.2 version of java.net.ServerSocket doesn't seem to work.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

$ java muffin.Main -help
Muffin Options:

-help                 This useful message.
-httpProxyHost HOST   Use HOST as the HTTP proxy.
-httpProxyPort PORT   Use PORT as the HTTP proxy port.
-port PORT            Listen on PORT for browser requests.

java muffin.Main

java muffin.Main -port 1234

Once muffin is running it will be ready to receive requests from your web browser. However, you still need to tell Muffin about your real HTTP proxy server. You can do this by entering the information in the Options... window or use the -httpProxyHost and -httpProxyPort options when you start Muffin. By default a host named proxy at port 3128 is used.

The main Muffin has a few buttons and a graphic display of the current HTTP transactions. Filters... will popup the filters window, Options... will popup the options window, Suspend will cause Muffin to not accept HTTP requests from the browser, and Stop will stop all HTTP transactions, similar to the Stop button in a web browser.

The default access privileges are to allow access to the IP address of the host Muffin is running on and to deny access to all others hosts.

A filter is started by selecting it from the Known Filters list and pressing the Run button. Now the filter should be listed in the Running Filters list. All filters in this list will sequentially process the HTTP requests and responses. The order can be changed by using the Move Up and Move Down buttons. The current status of the filter can be obtained using the View... button. A filter can be stopped an any time by pressing the Stop button. New filters can be added to the Known Filters list by pressing the New... button. You will need to enter a valid Java class path to specify the filter name. Examples would be java.lang.String, muffin.filters.SecretAgent, and test.TestFilter. You might need to modify the CLASSPATH environment variable to help java find classes that are not included in the system java classes or the current directory.

The following filters are included with Muffin: CookieMonster - Removes `Cookie' and/or `Set-Cookie' headers. [source] Logger - Keeps a log of all requested URLs. [source] SecretAgent - Changes `User-Agent' header that's sent by the browser. [source] SecretServer - Change `Server' header that's sent to the browser. [source] Snoop - Keep a log of all HTTP headers. [source] Stats - Maintain various stats about your HTTP session. [source]

filterRequest

public void filterRequest (Request r)

Filter the Request object.

public void filterReply (Reply r)

Filter the Reply object.

public void view ()

Display information about the filter. Most filters used this to create a Frame to display filter specific information and/or allow the user to set configuration options.

Note that Request and Reply are sub-classes of Message which contains the interface to HTTP headers. Request adds several functions like getRequest, getCommand, and getURL.

Look at the source code for the included filters for more information.

• The New... button in the Filters window doesn't work.

• Make the icon button do something useful.
• Add support for filtering HTML. (need good java HTML parser) A goal would be to remove advertisements or offenive HTML content.