= FAQ ===

Q: What is TCPMUX?
A: TCPMUX stands for "TCP Port Service Multiplexer". It is basically a
simple protocol for exposing multiple named services on a single port.
The protocol is described in RFC-1078. [1]

Q: Aren't there tcpmux servers already?
A: Yes, there are two that I know of (in inet.d and xinet.d), but you
cannot change the default port number from the IANA assigned tcpmux port,
and I wanted to use port 22, because of firewall restrictions. Also I
wanted something simple and easy to customize.

Q: What about clients?
A: I don't know about any widespread clients. Though netcat works with
some hacking :)

Q: So how do I use this?
A: You have to describe the services you want share in the configuration
file tcpmxd.cf. You can add simple tcp fowarders and internally defined
ruby functions. After that you have to run the server, and connect to it
with the client.

Q: How does the config file look like?
A: It's a simple ruby module:
    > module TCPMXDConf
    >     class Fortune
    >         def handle(client)
    >             client.puts %x["fortune"]
    >         end
    >     end
    >
    >     Services = {
    >       # forwarded services
    >         'ssh'       => {:type => :forward,  :host    => '127.0.0.1', :port   => 22      }, 
    >         'web'       => {:type => :forward,  :host    => '127.0.0.1', :port   => 80      },
    >       # internal service
    >         'fortune'   => {:type => :internal, :object  => Fortune.new, :method => :handle }
    >     }
    > end

Q: How does the client work?
A: It listens on a given port, and when a connection is made it forwards all
traffic to the server after doing a handshake.

= Example ===

:: Run the tcpmux daemon on target.box, binding to 0.0.0.0:22022:
> tcpmxd -d -p 22022

:: Connect to a tcpmux shell service running on port 22022 and bind to localhost:3333.
> tcpmxc -p 22022 target.box 3333 ssh

:: Then in another terminal you can:
> ssh user@localhost -p 3333

[1] http://tools.ietf.org/html/rfc1078