Simplest ngrok-like reverse tunnel

Do you need a simple reverse TCP tunnel to a local service (like SSH), but you don’t want to install anything or use a one of the public ones.

Warning: There is no authentication, use this only for temporary things or IP allowlisting to limit who can connect.

Get the sish binary from github

With that out of the way, on the server run

./sish --authentication=false --ssh-address=:9999 -i:9989 --bind-random-ports=false

then run on the client

ssh <server-ip> -p 9999 -tt -o StrictHostKeyChecking=no -o UserKnownHostsFile=/dev/null -R 12345:localhost:22