Ccm.ccm.xcrypt: def of bend-osdev-cipher-modes@0.1.0.0
Import: import bend-osdev-cipher-modes@0.1.0.0/ccm.bend as Ccm
Lines 74-78 of bend-osdev-cipher-modes@0.1.0.0/ccm.bend: https://jend.leeeet.dev/read.txt?path=bend-osdev-cipher-modes@0.1.0.0/ccm.bend&start_line=74&end_line=78

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

# CTR from counter 1: the whole blocks, then the tail xor the next S_i
def ccm.xcrypt(~K: Data, ~enc: K -> M.CmBlock -> M.CmBlock, +k: K, +a0: M.CmBlock, s: M.CmSplit) -> List<&2, U32>:
  match s:
    case M.CmSplit{+bs, tail}:
      M.cm.join_onto(ccm.ctrb(~K, ~enc, k, bs, a0, 1), M.cm.xor_bytes(tail, M.cm.bytes_of(enc(k, ccm.ai(a0, U32.add(1, U32.from_nat(List.length(&2, M.CmBlock, bs))))))))

Uses (12):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=List
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=List.length
  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=Base/base.bend&name=U32.from_nat
  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=CmSplit
  https://jend.leeeet.dev/definition.txt?path=bend-osdev-cipher-modes@0.1.0.0/cipher_modes.bend&name=cm.bytes_of
  https://jend.leeeet.dev/definition.txt?path=bend-osdev-cipher-modes@0.1.0.0/cipher_modes.bend&name=cm.join_onto
  https://jend.leeeet.dev/definition.txt?path=bend-osdev-cipher-modes@0.1.0.0/cipher_modes.bend&name=cm.xor_bytes