luks ssd idea

Vladimir Ivanovich <[email protected]> Mon, 22 Sep 2025 19:29:18 +0200
Newsgroups dev.linux.lists.cryptsetup
Message-ID <20250922192919.4d4b3992@desktop>
hello

luks default is disable ssd trim-discard command because leaks unused
blocks

what if shuffle data, maybe another mapper device, to leak less info?

fpe(n, key, i) = format preserving encryption, domain {0...n}
roll(n, offset, i) = (i + offset) % n

block_out = fpe(DISK_SIZE / BLOCK_SIZE, hkdf(LUKS_SHUFFLEBLOCK,
masterkey), block_in) page_out = roll(BLOCK_SIZE / PAGE_SIZE,
hash(hkdf(LUKS_SHUFFLEINDEX, masterkey) + block_in) % (BLOCK_SIZE /
PAGE_SIZE), page_in)

sorry for bad english, what you guys think of my proposal