def sp_lt1

bend-osdev-legacy-ciphers@0.1.0.0 · PROOF.bend:1171

import Base
import bend-osdev-cipher-modes@0.1.0.0/cipher_modes.bend as M
import bend-osdev-legacy-ciphers@0.1.0.0/serpent.bend as P

1171# the linear transformation's steps, each undone
1172def sp_lt1(s: M.CmBlock) -> {s == P.sp.ilt1(P.sp.lt1(s)) : M.CmBlock}:
1173  match s:
1174    case M.CmBlock{+x0, +x1, +x2, +x3}:
1175      %rot_19_13(x0) : {M.CmBlock{x0, x1, x2, x3} == M.CmBlock{_, x1, x2, x3} : M.CmBlock}
1176      {==}