Reverse Connecting Sock5 Proxy server c#

Question

I want to develop sock5 proxy server in c# which could make connections to client. ie in normal scenarios client or browser make connection to proxy server but i want the proxy server to connect to the client. i googled a lot but could not find any code sample in c# or other language.

Answer 1

This sounds like a rather broad question, but generally I think what you are trying to do isn't "by definition possible". Socks5 is defined in RFC1928 ( http://tools.ietf.org/html/rfc1928 ). It specifically relates to the 'client' connecting to the 'server'. In order for the proxy server to connect to the client, the client machine would have to have some form of service running and listening on a previously established port (assuming TCP/IP here). I suppose you could write some form of browser plugin or a service daemon to listen for server initiated connections; however, this wouldn't technically be 'socks5'. Having an open port (service) on your client open other security concerns, such as a connection from a machine claiming to be your server, or an outside machine requesting the proxy server to contact your client machine. Part of the trust model of these setups is the idea of client initiated actions. You may be trying to solve the wrong problem (ie you may need to reframe your problem in a different way).