Chapter

Advances in Cryptology – EUROCRYPT 2011

Volume 6632 of the series Lecture Notes in Computer Science pp 303-322

On Linear Hulls, Statistical Saturation Attacks, PRESENT and a Cryptanalysis of PUFFIN

  • Gregor LeanderAffiliated withDTU Mathematics, Technical University of Denmark

Abstract

We discuss complexities of advanced linear attacks. In particular, we argue why it is often more appropriate to examine the median of the complexity than the average value. Moreover, we apply our methods to the block ciphers PUFFIN and PRESENT. For PUFFIN, a 128 bit key cipher, we present an attack which breaks the cipher for at least a quarter of the keys with a complexity less than 258. In the case of PRESENT we show that the design is sound. The design criteria are sufficient to ensure the resistance against linear attacks, taking into account the notion of linear hulls. Finally, we show that statistical saturation attacks and multi dimensional linear attacks are almost identical.