Tcpbroker does TCP port forwarding with a twist – it connects two incoming sockets together. Tcpbroker allows you to telnet out from behind a firewall to another system also behind a firewall via a proxy host running the broker. All you need to do is remote command the far system to make the outgoing connection to the broker. Tcpbroker includes a secure authentication mechanism via Tiny SRP. A version without authentication is also included.
You can download it from the following link: https://packetstormsecurity.com/files/download/24137/tcpbroker-1.1.tar.gz
Source: https://packetstormsecurity.com/files/24137/tcpbroker-1.1.tar.gz.html