PROOF.ccmp.ctrb2: def of bend-osdev-cipher-modes@0.1.0.0
Import: import bend-osdev-cipher-modes@0.1.0.0/PROOF.bend as PROOF
Lines 1773-1781 of bend-osdev-cipher-modes@0.1.0.0/PROOF.bend: https://jend.leeeet.dev/read.txt?path=bend-osdev-cipher-modes@0.1.0.0/PROOF.bend&start_line=1773&end_line=1781

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/ccm.bend as CC

# CTR twice is the identity on blocks
def ccmp.ctrb2(~K: Data, ~enc: K -> M.CmBlock -> M.CmBlock, +k: K, bs: List<&2, M.CmBlock>, +a0: M.CmBlock, +i: U32) -> {CC.ccm.ctrb(~K, ~enc, k, CC.ccm.ctrb(~K, ~enc, k, bs, a0, i), a0, i) == bs : List<&2, M.CmBlock>}:
  match bs:
    case Nil{}:
      {==}
    case Con{+b, +rest}:
      %Equal.sym(M.CmBlock, M.CmBlock.xor(M.CmBlock.xor(b, enc(k, CC.ccm.ai(a0, i))), enc(k, CC.ccm.ai(a0, i))), b, bx.rblock(b, enc(k, CC.ccm.ai(a0, i)))) : {Con{_, CC.ccm.ctrb(~K, ~enc, k, CC.ccm.ctrb(~K, ~enc, k, rest, a0, U32.add(i, 1)), a0, U32.add(i, 1))} == Con{b, rest} : List<&2, M.CmBlock>}
      %Equal.sym(List<&2, M.CmBlock>, CC.ccm.ctrb(~K, ~enc, k, CC.ccm.ctrb(~K, ~enc, k, rest, a0, U32.add(i, 1)), a0, U32.add(i, 1)), rest, ccmp.ctrb2(~K, ~enc, k, rest, a0, U32.add(i, 1))) : {Con{b, _} == Con{b, rest} : List<&2, M.CmBlock>}
      {==}

Uses (9):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Equal.sym
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=List
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=U32
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=U32.add
  https://jend.leeeet.dev/definition.txt?path=bend-osdev-cipher-modes@0.1.0.0/PROOF.bend&name=bx.rblock
  https://jend.leeeet.dev/definition.txt?path=bend-osdev-cipher-modes@0.1.0.0/ccm.bend&name=ccm.ai
  https://jend.leeeet.dev/definition.txt?path=bend-osdev-cipher-modes@0.1.0.0/ccm.bend&name=ccm.ctrb
  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-cipher-modes@0.1.0.0/cipher_modes.bend&name=CmBlock.xor