pgplockd

A logind locker using PGP

Proposal

This program should be runnable as a systemd user service to periodically query the user's PGP key and lock the screen if the key is locked.

Workflow

• User logs in
• pgplockd starts
• Random message is generated and requested to be signed, timeout countdown starts
• User unlocks PGP key and signs message OR countdown locks screen
• Timer starts, then another message is generated

If the user does/can not unlock the PGP key (be it a removed smartcard or otherwise) logind should lock the screen.