TIL the French government may have broken encryption on a LUKS-encrypted laptop with a “greater than 20 character” password in April 2023.

When upgrading TAILS today, I saw their announcement changing LUKS from PBKDF2 to Argon2id.

The release announcement above has some interesting back-of-the-envelope calculations for the wall-time required to crack a master key from a LUKS keyslot with PBKDF2 vs Argon2id.

And they also link to Matthew Garrett’s article, which describes how to manually upgrade your (non-TAILS) LUKS header to Argon2id.

  • Eufalconimorph
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    1 year ago

    Yep, a 10 Diceware word passphrase is just as secure as a 128-bit encryption key, even if only HKDF were used instead of a password-based KDF. Key stretching matters when you have weak passphrases, and even Argon2 only adds a few bits of effective entropy with reasonable difficulty factors.