enc :: AES128 -> (Key, Key, Key) -> Key
enc fkey (a, b, o) =
    BS.pack $ BS.zipWith xor o $ hashPair fkey a b
enc :: AES128 -> (Key, Key, Key) -> Key
enc fkey (a, b, o) =
    BS.pack $ BS.zipWith xor o $ hashPair fkey a b
enc fkey (a, b, o) =
    BS.pack $ BS.zipWith xor o $ hashPair fkey a b