@grmpyoldman I don't really get the imagery there. I mean I quite like getting it from a hunky russian bear. Is it trying to suggest that it is unpleasant ?
@rtsn @lwflouisa You should check out the Cryptography 1 course from Coursera. https://www.coursera.org/learn/crypto It's just about to start again (Feb 19) . It's free, and covers the fundamentals of modern cryptography. It's really fun, and has some good !math in it too.
@rtsn @lwflouisa Have you considered how LUKS disk encryption is done when there are multiple passphrases for a device, or GPG when there are multiple recipients ? For example in LUKS a master key is used to encrypt the disk blocks, but the master key is encrypted with a passphrase and stored in a keyslot. There are multiple keyslots, corresponding to a different passphrase,each containing the master key encrypted with that passphrase. This allows multiple people to be able to decrypt the drive, but with independent passphrases. Similarly in GPG, the message is encrypted with symmetric cipher, with that key encrypted to a recipients public key, with that appended to the encrypted message. In that way multiple recipients can decrypt the message with their private keys.