Feature request: port forward, UDP

[dxlr8r]

As #9 but for UDP.

[af-airbus]

UDP forwarding is a far more complicated to implement, because UDP does not rely on a established bidirectional connection.
What protocol(s) above UDP (e.g. DNS) would you like to forward?

[dxlr8r]

Perhaps not an issue with TCP vs UDP, but SSH is very slow sometimes, so I wanted to test Mosh (UDP). I have 2FA in front of my SSH, so telnet is not an option.