I have a machine behind a big firewall, and I want to be able to access it via ssh without poking a hole through the firewall.
So, I reverse SSH from the machine behind the firewall into my private server. Then, I can simply ssh into my private server and tunnel into the machine I'm trying to access.
There is a small security problem with this though. To access the machine behind the firewall, I only need to authenticate to my private server, when I want to also authenticate to the machine behind the firewall (private key or password).
Is there a way to do this? I don't consider my private server to be extremely secure, so I'd like to keep the sshd layer of protection from the machine behind the firewall.
(Actually, do you even need to authenticate into the private server? I think maybe not, so this is a bigger hole than I thought)