Portfwd - Port Forwarding Daemon

Portfwd is a small C++ utility which forwards incoming TCP connections and/or UDP packets to remote hosts. It's available under GNU GPL.

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Example configuration file

Take a look at how a configuration file looks:

/*
  portfwd1.cfg
*/

tcp /* TCP connections */
{ 
        /*
         * Connections on port 12000 from subnet localhost/24 and
         * ports in the range 0-5000 are forwarded to 127.0.0.1:23.
         * Anything else goes to 127.0.0.1:80.
         */
        12000 { 
                localhost/24:+5000  => 127.0.0.1:23;
                /* anything else */ => 127.0.0.1:80
        };

        /*
         * On port 11000, connections from address localhost, any port,
         * are forwarded to 127.0.0.1:23.
         */
        11000 { localhost => 127.0.0.1:23 }
}

udp /* UDP packets */
{
        /*
         * All packets on port 10000 are forwarded to 127.0.0.1:11000.
         */
        10000 { => 127.0.0.1:11000 }
}