This plugin tries to detect transparent proxies. The procedure for detecting transparent proxies is simple, I try to connect to a series of IP addresses, to the port 80, if all of them return an opened socket, then it’s the proxy server responding.
This plugin doesn’t have any user configured options.
For more information about this plugin and the associated tests, there’s always the source code to understand exactly what’s under the hood:
Plugin source code
Unittest source code
This plugin has no dependencies.