special passphrase(s) that execute a kill-command

[philcerf]

 * Cinnamon-Screensaver version 5.6.1
 * Distribution Debian

Issue
It would be nice, when one could configure a special passphrase (or maybe even more) which, when entered, doesn't unlock the screensaver, but instead executes a configurable command (depending on which passphrase was entered).

Such command could then be used, to forcibly shutdown the machine or remove any dm-crypt keys from memory.

Regards,
Philippe.

PS: Yes I know that a skilled attacker would rather perform e.g. a cold boot attack, but still, might help in some cases.