LowMC实例的差分枚举攻击效果分析

Effect of the difference enumeration attack on LowMC instances

LowMC是具有低乘法复杂度特征的算法。针对低数据量和少量S盒参数下的LowMC实例,差分枚举攻击被提出,理论上可以攻击全轮LowMC算法。考虑到这种攻击是在线性层完全随机的条件下给出的,对LowMC算法在真实的线性层下抵抗差分枚举攻击的强度进行了研究。通过对关键起始轮数的研究发现,差分枚举攻击并非总是可以达到理论攻击轮数。对于某一些关键起始轮数比理论值小的LowMC实例,差分枚举攻击甚至会失败。由于LowMC算法的轮数设置基于现有攻击的效果,该分析对LowMC算法的轮数设计具有重要意义。

The LowMC is an algorithm with low multiplicative complexities.For the parameter with limited data complexities and low number of S-boxes,the difference enumeration attack was proposed,which could theoretically attack all rounds of the LowMC.Considering that the original attack is based on the random linear layer,the strength of LowMC algorithm against differential enumeration attacks under a specific linear layer deserves more study.The difference enumeration attack cannot reach theoretical rounds through the research on the so-called key initial round.In terms of some LowMC instances,the key initial round is smaller than the theoretical value,which leads to the failure of the difference enumeration attack.Since the number of rounds of the LowMC is completely based on ex-isting attacks,the analysis is of great significance to the rounds design of the LowMC.