Edit/Solved: Thank you for all the great input! Both on alternative solutions and on security implications. I’m going to make a draft on how I would setup the e-mail method as securely as possible as a programming/scripting exercise, but will IRL probably end up using either some reverse tunnel/shell variant.
Edit 2: or, as a hardware solution, install an extra NIC that I expose to the opennet - thus enabling remote port forwarding - while binding all my sensitive processes/traffic to my encrypted NIC.
I cannot ssh into my Linux box from outside of my LAN since I’m behind a VPN that doesn’t support port forwarding. Is it possible to make my Linux box receive, interpret and execute commands through e-mail instead? I’ve tried looking for answers through DuckDuckGo’s search engine, to no avail. If I may dream, I would like to setup an e-mail server with a systemd service or just run a script that continuously downloads the emails, prints their content to stdin and executes, perhaps through command substitution, whatever is in stdin.


Now THAT sounds like a smart solution! I’ll look into it! :) I can ask my ISP to give me a static address for my home. But something needs to prompt the ssh command “at home” to connect to my second computer, right (actually Termux on my Android phone)?
It can be a Cron job that runs every minute. Run a script that:
Thanks! I’ll noodle it around a little. :)