Linear-Differential Cryptanalysis for SPN Cipher Structure and AES  

作　　者：WEI Yongzhuang HU Yupu 

机构地区：[1]Key Laboratory of Computer Networks and Information Security, Ministry of Education, Xidian University, Xi＇ an 710071, Shaanxi, China [2]Guilin University of Electronic Technology, Guilin541004, Guangxi, China

出　　处：《Wuhan University Journal of Natural Sciences》2007年第1期37-40,共4页武汉大学学报（自然科学英文版）

基　　金：Supported by the National Natural Science Foun-dation of China(60503010) and the Foundation of National Laboratory for Modern communications(51436030105DZ0105)

摘　　要：A new attack on block ciphers is introduced, which is termed linear-differential cryptanalysis. It bases the combining of linear cryptanalysis and differential cryptanalysis, and works by using linear-differential probability （LDP）. Moreover, we present a new method for upper bounding the maximum linear-differential probability （MLDP） for 2 rounds of substitution permutation network （SPN） cipher structure. When our result applies to 2-round advanced encryption standard（AES）, It is shown that the upper bound of MLDP is up to 1.68×2^-19, which extends the known results for the 2-round SPN. Furthermore, when using a recursive technique, we obtain that the MLDP for 4 rounds of AES is bounded by 2^-73.A new attack on block ciphers is introduced, which is termed linear-differential cryptanalysis. It bases the combining of linear cryptanalysis and differential cryptanalysis, and works by using linear-differential probability （LDP）. Moreover, we present a new method for upper bounding the maximum linear-differential probability （MLDP） for 2 rounds of substitution permutation network （SPN） cipher structure. When our result applies to 2-round advanced encryption standard（AES）, It is shown that the upper bound of MLDP is up to 1.68×2^-19, which extends the known results for the 2-round SPN. Furthermore, when using a recursive technique, we obtain that the MLDP for 4 rounds of AES is bounded by 2^-73.

关 键 词：linear-differential cryptanalysis substitution permutation network advanced encryption standard （AES）. 

分 类 号：TN918.1[电子电信—通信与信息系统]