Decorrelation: A Theory for Block Cipher Security

Provable Security for Block Ciphers by Decorrelation

The Security of Cipher Block Chaining

The Cipher Block Chaining { Message Authentication Code (CBC MAC) speciies that a message x = x 1 x m be authenticated among parties who share a secret key a by tagging x with a preex of f (m) a (x) def = f a (f a (f a (f a (x 1)x 2) x m?1)x m) ; where f is some underlying block cipher (eg. f = DES). This method is a pervasively used international and U.S. standard. We provide its rst formal ju...

Security Analysis of the Block Cipher Camellia

The Security of the RC6TM Block Cipher

This report presents a preliminary analysis of the security o ered by the RC6 TM block cipher. RC6 is an evolutionary improvement of RC5, designed to meet the requirements of the Advanced Encryption Standard (AES). Our analysis demonstrates that RC6 is highly resistant to di erential and linear cryptanalytic attack, which are currently the two most e ective analytical attacks on block ciphers. ...

Security Evaluation against Differential Cryptanalysis for Block Cipher Structures

Estimating immunity against differential and linear cryptanalysis is essential in designing secure block ciphers. A practical measure to achieve it is to find the minimal number of active S-boxes, or a lower bound for this minimal number. In this paper, we provide a general algorithm using integer programming, which not only can estimate a good lower bound of the minimal differential active S-b...