PAM Duress – Alternate passwords for panic situations
There are multiple levels of protection one might want.<p>I.e. when you are being selected for random questioning entering US as a non-US citizen, you'd benefit from steganography-like approach: you give a password, and relatively bland, non-personal stuff shows up, giving appearance of full access to a system.<p>If you only care about your privacy, the next one is to have a destroy-everything script (and it's not that hard: usually, passphrases are only used to decrypt the actual encryption keys, so overwriting those keys should be super fast).  This would also work against unsophisticated attacks which are not going to really cost you your life.<p>If there is a potential for you to be a target of a sophisticated attack and the attacker does not care about taking your life, the biggest benefit is to have a way to inform someone of your whereabouts while you are actually giving access, ideally in a way that buys you time (eg. "webcam has detected stress on your face, please wait another 6 hours before trying to log in again" — sorry, company mandated software, when it happens usually, we call support).