AesModes.CmAes.xts_decrypt: def of bend-osdev-cipher-modes@0.1.0.0
Import: import bend-osdev-cipher-modes@0.1.0.0/aes_modes.bend as AesModes
Lines 49-56 of bend-osdev-cipher-modes@0.1.0.0/aes_modes.bend: https://jend.leeeet.dev/read.txt?path=bend-osdev-cipher-modes@0.1.0.0/aes_modes.bend&start_line=49&end_line=56

import Base
import bend-osdev-bytes@0.1.0.0/bytes.bend as B
import bend-osdev-cipher-modes@0.1.0.0/cipher_modes.bend as M
import bend-osdev-cipher-modes@0.1.0.0/aes.bend as X
import bend-osdev-cipher-modes@0.1.0.0/xts.bend as T

def CmAes.xts_decrypt(+key: B.Octets, i: B.Octets, c: B.Octets) -> Result<&2, &2, M.CmError, B.Octets>:
  +n = B.Octets.len(key)
  +h = Nat.div(n, 2n)
  do Result<&2, &2, M.CmError, B.Octets>:
    M.cm.check(Bool.or(Nat.is_eq(n, 32n), Nat.is_eq(n, 64n)), M.CmBadKeyLength{n})
    k1 : X.CmAesKey <- X.CmAes.key(B.Octets.take(h, key))
    k2 : X.CmAesKey <- X.CmAes.key(B.Octets.drop(h, key))
    T.Xts.decrypt(~X.CmAesKey, ~X.CmAes.encrypt, ~X.CmAes.decrypt, X.CmAes.prepare(k1), k2, i, c)

Uses (18):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Bool.or
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Nat.div
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Nat.is_eq
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Result
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Result.bind
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Unit
  https://jend.leeeet.dev/definition.txt?path=bend-osdev-bytes@0.1.1.1/bytes.bend&name=Octets
  https://jend.leeeet.dev/definition.txt?path=bend-osdev-bytes@0.1.1.1/bytes.bend&name=Octets.drop
  https://jend.leeeet.dev/definition.txt?path=bend-osdev-bytes@0.1.1.1/bytes.bend&name=Octets.len
  https://jend.leeeet.dev/definition.txt?path=bend-osdev-bytes@0.1.1.1/bytes.bend&name=Octets.take
  https://jend.leeeet.dev/definition.txt?path=bend-osdev-cipher-modes@0.1.0.0/aes.bend&name=CmAes.decrypt
  https://jend.leeeet.dev/definition.txt?path=bend-osdev-cipher-modes@0.1.0.0/aes.bend&name=CmAes.encrypt
  https://jend.leeeet.dev/definition.txt?path=bend-osdev-cipher-modes@0.1.0.0/aes.bend&name=CmAes.key
  https://jend.leeeet.dev/definition.txt?path=bend-osdev-cipher-modes@0.1.0.0/aes.bend&name=CmAes.prepare
  https://jend.leeeet.dev/definition.txt?path=bend-osdev-cipher-modes@0.1.0.0/aes.bend&name=CmAesKey
  https://jend.leeeet.dev/definition.txt?path=bend-osdev-cipher-modes@0.1.0.0/cipher_modes.bend&name=CmError
  https://jend.leeeet.dev/definition.txt?path=bend-osdev-cipher-modes@0.1.0.0/cipher_modes.bend&name=cm.check
  https://jend.leeeet.dev/definition.txt?path=bend-osdev-cipher-modes@0.1.0.0/xts.bend&name=Xts.decrypt