1

Suppose you have a cryptographic permutation consisting of identical rounds, that makes it vulnerable to a slide attack. But if you sandwich it between two XORs of key material. Is it still vulnerable?

Even-Mansour block cipher construction works on such a principle although it says nothing about a permutation with identical rounds.

What is the reason for why AES and most other block ciphers employ a key schedule instead of an Even-Mansour construction?

  • Are you suggesting a cipher combining a 256 bit key Even-Mansour using as permutation AES with all round keys at zero ? – Ruggero Sep 03 '19 at 10:56
  • Yes. Though it does not have to be 256 bits, 128 also suffices. According to later proof that the same key can be used to whiten and apply post with no loss of security. –  Sep 03 '19 at 20:16
  • This seems to be a duplicate of https://crypto.stackexchange.com/questions/30221/is-there-any-reason-not-to-use-single-key-em-with-aes-and-a-constant-key/30353 – Samuel Neves Sep 05 '19 at 07:55

0 Answers0