Disabling integrity metadata verification (was: Equivalent of --integrity-recalculate)
Marc SCHAEFER <[email protected]> Sun, 11 May 2025 10:25:30 +0200
| Newsgroups | dev.linux.lists.cryptsetup |
|---|---|
| Message-ID | <[email protected]> |
Hello, Thank you for this insight: On Sat, May 10, 2025 at 06:18:18PM +0200, Milan Broz wrote: > Note, for integritysetup you use dm-integrity, for cryptsetup > dm-integrity only provides metadata space, AEAD encrypton > is performed in dm-crypt above. So, if I understand well, integrity with cryptsetup is implemented with a HMAC that needs cleartext data (just before encryption) and produce hashed-signed integrity data that protects against tampering and is not fixable by an attacker (resistant to voluntary corruption). Where if I create a dm-integrity layer with a luks crypted volume on top, I get integrity, but an attacker can modify the crypted data and the hash easily (only resistant to accidental corruption). Now, another question: assuming the metadata space is corrupted, but I know that the crypted space is not, is it possible to ignore the metadata altogether (to not produce read errors)? Thank you.