PROOF.sm4_unstep_step: def of bend-osdev-legacy-ciphers@0.1.0.0
Import: import bend-osdev-legacy-ciphers@0.1.0.0/PROOF.bend as PROOF
Lines 239-243 of bend-osdev-legacy-ciphers@0.1.0.0/PROOF.bend: https://jend.leeeet.dev/read.txt?path=bend-osdev-legacy-ciphers@0.1.0.0/PROOF.bend&start_line=239&end_line=243

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/legacy_ciphers.bend as L
import bend-osdev-legacy-ciphers@0.1.0.0/sm4.bend as S

def sm4_unstep_step(+tab: L.LcTab, +rk: U32, s: M.CmBlock) -> {s == S.sm4.unstep(tab, rk, S.sm4.step(tab, rk, s)) : M.CmBlock}:
  match s:
    case M.CmBlock{x0, +x1, +x2, +x3}:
      %u32_xx(x0, S.sm4.t(tab, U32.xor(U32.xor(U32.xor(x1, x2), x3), rk))) : {M.CmBlock{x0, x1, x2, x3} == M.CmBlock{_, x1, x2, x3} : M.CmBlock}
      {==}

Uses (8):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=U32
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=U32.xor
  https://jend.leeeet.dev/definition.txt?path=bend-osdev-cipher-modes@0.1.0.0/cipher_modes.bend&name=CmBlock
  https://jend.leeeet.dev/definition.txt?path=bend-osdev-legacy-ciphers@0.1.0.0/PROOF.bend&name=u32_xx
  https://jend.leeeet.dev/definition.txt?path=bend-osdev-legacy-ciphers@0.1.0.0/legacy_ciphers.bend&name=LcTab
  https://jend.leeeet.dev/definition.txt?path=bend-osdev-legacy-ciphers@0.1.0.0/sm4.bend&name=sm4.step
  https://jend.leeeet.dev/definition.txt?path=bend-osdev-legacy-ciphers@0.1.0.0/sm4.bend&name=sm4.t
  https://jend.leeeet.dev/definition.txt?path=bend-osdev-legacy-ciphers@0.1.0.0/sm4.bend&name=sm4.unstep