低轮FOX64算法的零相关-积分分析  

Integral Cryptanalysis of Reduced Round FOX64

作　　者：郭瑞[1] 金晨辉[1] 

机构地区：[1]解放军信息工程大学三院,郑州450001

出　　处：《电子与信息学报》2015年第2期417-422,共6页Journal of Electronics & Information Technology

基　　金：国家自然科学基金(61272488)资助课题

摘　　要：FOX系列算法是一类基于Lai-Massey模型设计的分组密码算法。该文首先评估低轮FOX64算法抵抗零相关线性分析的能力,给出4轮FOX64算法的零相关线性区分器。然后,利用零相关线性区分器与积分区分器的关系,首次得到4轮FOX64算法的积分区分器。最后,利用积分区分器分析5,6,7,8轮FOX64算法,攻击的时间复杂度分别约为252.7,2116.7,2180.7,2244.7次加密,数据复杂度为250个选择明文。该文首次给出攻击8轮FOX64/256时间复杂度小于穷举攻击的有效攻击。FOX family block ciphers are based on Lai-Massey scheme. Firstly, the evaluation is performed on the ability of the reduced round FOX64 to resist zero-correlation linear cryptanalysis, and some 4-round zerocorrelation linear distinguishers are presented. Then, by using the relation between the integral distinguishers and zero-correlation distinguishers, the 4-round integral distinguishers of FOX64 are found. Finally, the 4-round integral distinguishers are used to attack 5, 6, 7 and 8 rounds FOX64 with the time complexity of 2^52.7, 2^116.7, 2^180.7and 2^244.7 encryptions respectively, and the data complexity is 2^50 chosen plaintexts. This is the first paper pointing out that 8-round FOX64/256 is vulnerable against the statistical attack.

关 键 词：密码学 分组密码 密码分析 FOX64算法 零相关-积分分析 

分 类 号：TN918[电子电信—通信与信息系统]