I have a local machine M that I want to expose to the internet, and I can't use port forwarding. I want to open port 22 on M to the internet, using my vps S as a proxy. I want to use this port to have ssh access, so the solution must allow all tcp traffic, not just http, as many other questions have asked here. I have tried using ssh -f -N -R 9000:localhost:22 example.com on M, where localhost is M and example.com is a domain name pointing to S. This allows machine S to access M over S:9000, but not arbitrary machines on the internet to access M through example.com:9000, which is what I want. (note that the port that arbitrary machines connect to does not necessarily need to be the same port that S can connect to M through.) I tried using an nginx tcp reverse proxy, but it doesn't seem to work.
Some notes:
The forwarding itself does not need to be done using ssh, I know it is somewhat slow.
I intend to leave this running for long periods of time (I know this might be a security risk).
If it matters at all, M runs Arch Linux, and S runs Debian 10 Buster.
