摘要: 对作为Blow-CAST-Fish算法子密钥的4个S盒的碰撞性进行分析,构造输入差分为非零、输出差分为零的轮函数F的差分特征,通过对算法进行差分分析,获取相关子密钥,并测试使特征成立的弱密钥概率。在此基础上,成功利用特征概率为2-61、弱密钥概率为 2-12的6轮差分特征攻击8轮Blow-CAST-Fish算法。
关键词:
Blow-CAST-Fish算法,
差分攻击,
差分特征,
弱密钥,
轮函数,
S盒,
碰撞
Abstract: By analyzing the collision of four S-boxes which are subkeys of Blow-CAST-Fish, this paper develops the differential characteristic of function F with non-zero inputxor and a zero outputxor, performs a differential cryptanalysis of the algorithm to recover the rest of the subkeys, and tests the proportion of weak keys which can produce the differential characteristic. Based on this, it succeeds in using the 6-round differential characteristic with the probability 2-61 under 2-12 of the total key space to attack 8-round Blow-CAST-Fish.
Key words:
Blow-CAST-Fish algorithm,
differential attack,
differential characteristic,
weak key,
round function,
S-box,
collision
中图分类号:
孙晓玲, 王美琴, 李忠, 孙旭光, 李姗姗, 杨秋格, 曹桂荣, 潘志安. 低轮Blow-CAST-Fish算法的差分攻击[J]. 计算机工程, 2012, 38(12): 99-101.
SUN Xiao-Ling, WANG Mei-Qin, LI Zhong, SUN Xu-Guang, LI Pan-Pan, YANG Qiu-Ge, CAO Gui-Rong, BO Zhi-An. Differential Attack on Reduced-round Blow-CAST-Fish Algorithm[J]. Computer Engineering, 2012, 38(12): 99-101.