Midori64的相关密钥不可能差分分析

Related-key differential analysis of Midori64

Midori算法是由Banik等人在AISACRYPT2015上提出的一种具有SPN结构的轻量级的加密算法。Midori的分组长度有64 bit和128 bit两种,分别为Midori64和Midori128。对Midori64进行研究,目前攻击者已经使用了不可能差分分析、中间相遇攻击、相关密钥差分分析等方法对Midori进行分析,却没有使用相关密钥不可能差分分析进行分析。为了验证Midori算法的安全性,使用了相关密钥不可能差分分析Midori算法,构造了一个Midori算法的9轮区分器,进行了Midori算法的14轮攻击,总共猜测了84 bit密钥。

Midori algorithm is a lightweight encryption algorithm with a SPN structure proposed by Banik et al. on AISACRYPT 2015. There are two versions of Midori with state sizes of 64 bit and 128 bit respectively. The study of Midori64 showed that,at present,the attacker used the impossible differential,meet-in-the-middle attack and related-key difference to analyze the Midori,but it had not been analyzed by using the related-key impossible differential analysis. In order to verify the security of the Midori algorithm,this paper used the related-key impossible differential to analyze the Midori algorithm and constructed a 9-round distinguisher,then it mounted 14-round related-key impossible differential attack on Midori64,a total of guess the 84 bit key.