law cast5_cbc_round_trip

bend-osdev-crypto@0.1.0.0 · LAWS.bend:1027

import Base
import bend-osdev-legacy-ciphers@0.1.0.0/legacy_ciphers.bend as L
import bend-osdev-legacy-ciphers@0.1.0.0/cast5.bend as C5
import bend-osdev-crypto@0.1.0.0/modes.bend as Md
import bend-osdev-crypto@0.1.0.0/inst_lc.bend as LC

1027# CAST-128 (legacy-ciphers) in CBC (modes.bend): decryption undoes encryption, for every key, IV and list of blocks
1028law cast5_cbc_round_trip:
1029  for +k: C5.LcCast5Key
1030  for +iv: L.LcBlock64
1031  for +bs: List<&2, L.LcBlock64>
1032  {Md.CrCbc.decrypt_blocks(~C5.LcCast5Key, ~L.LcBlock64, ~C5.LcCast5.decrypt, ~LC.CrBlk64.xor, k, iv, Md.CrCbc.encrypt_blocks(~C5.LcCast5Key, ~L.LcBlock64, ~C5.LcCast5.encrypt, ~LC.CrBlk64.xor, k, iv, bs)) == bs : List<&2, L.LcBlock64>}