[backup] save backups remotely in a save manner

[Akira25]

idea from firmware-meeting at 05.05.2020

Everytime autoupdate pushes a backup, scp asks for a password. The router should have an ssh-key to actively push files on other systems. This key might be generated not only for autoupdate, but for the router itself.

[sarumpaet]

One problem with pushing via scp is that if the sender gets compromised, it'd be easy for an attacker to a) compromise upstream backups, and b) possibly compromise the entire upstream system. I'm not sure what scope the backup solution is intended for, but for general use I'd rather recommend using something else (e.g., POSTing possibly encrypted backup data along with a recovery email address to some HTTPS backup server that keeps incremental copies of backups).

[Akira25]

Initially I thought of this backup function of a merely private function: The function should have only give the comfort of pushing the backups automatically into an archive-directory on the owners laptop.

We should defnitely discuss on a more secure solution, which could maybe incorporate pushing to (dezentralised) Servers.