Provable Security for the Skipjack-like Structure against Differential Cryptanalysis and Linear Cryptanalysis

In this paper we introduce a structure iterated by the rule A of Skipjack and show that this structure is provably resistant against differential or linear attacks. It is the main result of this paper that the upper bound of r-round (r 15) differential(or linear hull) probabilities are bounded by p4 if the maximum differential (or linear hull) probability of a round function is p, and an impossible differential of this structure does not exist if r 16. Application of this structure which can be seen as a generalized Feistel structure in a way to block cipher designs brings out the provable security against differential and linear attacks with some upper bounds of probabilities. We also propose an interesting conjecture.

• Type: Conference
• Year: 2000
• Where: ASIACRYPT
• Authors: Jaechul Sung, Sangjin Lee, Jong In Lim, Seokhie Hong, Sangjoon Park
• Keywords: ASIACRYPT 2000, Cryptology, Linear Attacks, Linear Hull, Upper Bounds