Improvements for Finding Impossible Differentials of Block Cipher Structures

Yiyuan Luo; Xuejia Lai

Paper 2017/1209

Improvements for Finding Impossible Differentials of Block Cipher Structures

Yiyuan Luo and Xuejia Lai

Abstract

In this paper we improve Wu and Wang's method for finding impossible differentials of block cipher structures. This improvement is more general than Wu and Wang's method that it can find more impossible differentials with less time. We apply it on Gen-CAST256, Misty, Gen-Skipjack, Four-Cell, Gen-MARS, SMS4, MIBS, Camellia*, LBlock, E2 and SNAKE block ciphers. All impossible differentials discovered by the algorithm are the same as Wu's method. Besides, for the 8-round MIBS block cipher, we find 4 new impossible differentials, which are not listed in Wu and Wang's results. The experiment results show that the improved algorithm can not only find more impossible differentials, but also largely reduce the search time.

Note: Minor Revision: some typos are corrected and more reference are added.

Metadata

Available format(s): PDF
Publication info: Published elsewhere. Security and Communication Networks 2017
DOI: 10.1155/2017/5980251
Keywords: block cipher cryptanalysis impossible differential Automatic search
Contact author(s): luoyiyuan777 @ qq com
History: 2017-12-25: revised; 2017-12-18: received; See all versions
Short URL: https://ia.cr/2017/1209
License: CC BY

BibTeX

@misc{cryptoeprint:2017/1209,
      author = {Yiyuan Luo and Xuejia Lai},
      title = {Improvements for Finding Impossible Differentials of Block Cipher Structures},
      howpublished = {Cryptology {ePrint} Archive, Paper 2017/1209},
      year = {2017},
      doi = {10.1155/2017/5980251},
      url = {https://eprint.iacr.org/2017/1209}
}