Linux Blog

Login Script to Phone Home

Filed under: Quick Linux Tutorials — at 11:59 pm on Monday, October 7, 2013

If you’re a little paranoid like me, you often wonder what will happen if your laptop gets stolen. I’ve seen news articles and the like where an thief happened to steal a laptop and got caught because they stole the wrong persons laptop.

Today we have a one liner that will phone home when a user logs in. While this wont work if you have a password on your laptop, which is recommended, if you keep a dummy account called “User” or “Guest” with no password and the thief happens to log in, you could be in luck.

ssh -N -R2222:localhost:22 <user>@<yourhost> -p<port> -i /home/<user>/.ssh/id_rsa

The simple SSH command opens up a remote port 2222 to the local port 22 which of course requires SSH to be running locally. It also uses the ssh identity file, for ano password ssh login, and the -N is for no shell. Set it up as an application that starts on login and if that account is set to auto connect to WiFi, it will connect as the user logs in. If you wanted to take it a step further you could combine it with autossh to continue trying to connect. It will also help if you have a static IP or DNS setup so that it will be able to connect if your device unfortunately goes missing.