אורי אברהם, הרצאה סמינריונית למגיסטר
יום רביעי, 23.2.2011, 13:00
We suggest a new framework for block ciphers named Advanced Block Cipher, or shortly ABC.
ABC has additional non-secret parameters that ensure that each call to the underlying block cipher uses a different pseudo-random permutation. It therefore ensures that attacks that require more than one block encrypted under the same secret permutation cannot apply. In particular, this framework protects against dictionary attacks, and differential and linear attacks, and eliminates weaknesses of ECB and CBC modes. This new framework shares a common structure with HAIFA, and can share the same logic with HAIFA compression functions. We analyze the security of several modes of operation for ABCs block ciphers, and suggest a few instances of ABCs.