Cryptology ePrint Archive: Report 2010/155

the upper bounds on differntial characteristics in block cipher SMS4

Zhang MeiLing and Liu JingMei and Wang XinMei

Abstract: SMS4 is a 128-bit block cipher with a 128-bit user key and 32 rounds, which is used in the Chinese National Standard for Wireless LAN WAPI. In this paper, all possible differential patterns are divided into several sections by six designed rules. In order to evaluate the security against the differential cryptanalysis of SMS4, we calculate the lower bounds on the number of active S-Boxes for all kinds of sections, based on which the lower bounds on the number of active S-Boxes in all possible differential patterns can be derived. Finally, the upper bounds on differential characteristic probabilities of arbitrary round numbers are given, which can be used to estimate the strength of SMS4 against differential attack and linear attack.

Category / Keywords: secret-key cryptography / block cipher SMS4

Date: received 23 Mar 2010, last revised 25 Mar 2010

Contact author: zhangmlwy at gmail com

Available format(s): PDF | BibTeX Citation

Version: 20100325:083732 (All versions of this report)

Short URL: ia.cr/2010/155

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