密码学报（中英文）2024，Vol.11Issue(5)：1078-1089,12.DOI:10.13868/j.cnki.jcr.000727
LiCi算法的相关密钥不可能差分分析
Impossible Differential Analysis of Correlation Key of LiCi Algorithm
摘要
Abstract
Impossible differential attack is an important key recovery attack.It uses the unlikely differential feature with probability of 0 to filter the wrong candidates.It has been widely used in a variety of block cipher analysis.LiCi algorithm is a new lightweight block cipher algorithm proposed by Patil et al.in 2017.This algorithm is based on the balanced Feistel structure,and uses new lightweight block cipher design such as lightweight S-boxes and simple shift operations.A relatively large number of active S-boxes can be generated using less round function operations.This algorithm has the characteristics of compact structure,low energy consumption,small footprint,and is suitable for resource constrained environments.At present,the best analysis results on LiCi algorithm are 16 rounds of differential analysis and 17 rounds of impossible differential analysis.In order to further study the resistance of LiCi algorithm against impossible differential attacks,this paper constructs an 11 round impossible differential distinguisher,and extends it forward for 3 rounds and backward for 3 rounds.Combined with the input and output characteristics of the S-box,17 rounds of LiCi algorithm is analyzed using impossible differential analysis method,where the data complexity is 261.59,the time complexity is 275.5,and the storage complexity is 272.59.Compared with the known results,this attack reduces the data complexity and time complexity when the number of attack rounds is the same.Meanwhile,this paper combines the characteristics of the key expansion algorithm and the round function characteristics to construct three 16 round correlation key impossible differential distinguishers,and selects one of them to expand three rounds forward and two rounds backward.Combined with the input and output characteristics of the S-box,this paper analyzes the 21 round LiCi algorithm by using the correlation key and impossible differential combination method.The data complexity of the analysis is 261.2,the time complexity is 268.05,and the storage complexity is 275.2.This shows that the 21 round LiCi algorithm is not immune to impossible differential cryptanalysis of related keys.关键词
LiCi算法/轻量级分组密码/不可能差分/相关密钥Key words
LiCi algorithm/lightweight block cipher/impossible differential attack/correlated-key分类
信息技术与安全科学引用本文复制引用
吴铜,袁征,魏锦鹏,申龙..LiCi算法的相关密钥不可能差分分析[J].密码学报（中英文）,2024,11(5):1078-1089,12.基金项目
中央高校基本科研业务费(328202268)the Fundamental Research Funds for the Central Universities of China(328202268) （328202268）
