def xtsp.go

bend-osdev-cipher-modes@0.1.0.0 · PROOF.bend:1378

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

1378def xtsp.go(~K: Data, ~enc: K -> M.CmBlock -> M.CmBlock, ~dec: K -> M.CmBlock -> M.CmBlock, ~inv: @k: K -> @b: M.CmBlock -> {dec(k, enc(k, b)) == b : M.CmBlock}, +k: K, bs: List<&2, M.CmBlock>, +t: M.CmBlock) -> {T.xts.dec(~K, ~dec, k, T.xts.enc(~K, ~enc, k, bs, t), t) == bs : List<&2, M.CmBlock>}:
1379  match bs:
1380    case Nil{}:
1381      {==}
1382    case Con{+p, +rest}:
1383      %Equal.sym(M.CmBlock, T.xts.bdec(~K, ~dec, k, T.xts.benc(~K, ~enc, k, p, t), t), p, xtsp.blk(~K, ~enc, ~dec, ~inv, k, p, t)) : {Con{_, T.xts.dec(~K, ~dec, k, T.xts.enc(~K, ~enc, k, rest, T.Xts.mul_alpha(t)), T.Xts.mul_alpha(t))} == Con{p, rest} : List<&2, M.CmBlock>}
1384      %Equal.sym(List<&2, M.CmBlock>, T.xts.dec(~K, ~dec, k, T.xts.enc(~K, ~enc, k, rest, T.Xts.mul_alpha(t)), T.Xts.mul_alpha(t)), rest, xtsp.go(~K, ~enc, ~dec, ~inv, k, rest, T.Xts.mul_alpha(t))) : {Con{p, _} == Con{p, rest} : List<&2, M.CmBlock>}
1385      {==}