Tang Xue-hai① Li Chao①② Wang Mei-yi① Qu Long-jiang①
①(Department of Mathematics and System Science, National University of Defense Technology, Changsha 410073, China) ②(State Key Laboratory of Information Security, Beijing 100190, China)
Abstract:3D cipher is a new block cipher proposed in CANS2008. It is different from all known block cipher as it uses the three dimension structure. The designers give out a 5-round impossible differential and make an impossible differential attack on 6-round 3D cipher. In this paper, some new 6-round impossible differentials are found according to its structure properties. Based on these new impossible differentials and the equivalent structure of 3D cipher, effective impossible differential attacks can be made on 7 and 8-round 3D cipher. Moreover, according to some properties of the key schedule, these attacks can be extended to 9-round 3D cipher. These attack results are better than the designer’s.