A simple app could be used by parties on both ends of the message—an app that relies on an associated drive to act as the pad.
If you become aware that one of the two matched drives has been compromised (stolen perhaps by an outside party), you destroy its partner.
(Perhaps too you can design the drive in such a way as to make it non-trivial to copy—you more or less need possession of the drive itself. That makes it unlikely for there to be a 3rd drive the two parties are unaware of.)
Not necessarily. The CSPRNG state could in theory be leaked via sidechannels. Your cipher key could be leaked via sidechannels too, but symmetric encryption keys tend to be shorter lived.
geerlingguy•27m ago
It's certainly not a scalable solution for entropy, and there are so many ways for it to fail as a sole source, as well.
dheera•19m ago
This is SF. If they were really used for anything, a random dude in a black hoodie and white SUV can just smash the glass and take down the internet, and the SF police wouldn't do a thing.