摘要
该文研究了LBlock分组密码算法在相关密钥-不可能差分条件下的安全性.利用子密钥生成算法的差分信息泄漏规律,构造了多条低重量子密钥差分链,给出了15轮相关密钥-不可能差分区分器.通过扩展区分器,给出了23轮和24轮LBlock算法的相关密钥-不可能差分攻击方法.攻击所需的数据复杂度分别为2^(65.2)和2^(65.6)个选择明文,计算复杂度分别为2^(66.2)次23轮LBlock算法加密和2^(66.6)次24轮LBlock算法加密,存储复杂度分别为2^(61.2)和2^(77.2)字节存储空间.与已有结果相比,首次将针对LBlock算法的攻击扩展到了23轮和24轮.
In this paper,the strength of LBlock against related-key impossible differential attack is examined.Based on the differential information leakages in sub-key schedule,several sub-key differentials in low weight are constructed,and a 15-round re-lated-key impossible differential distinguisher of LBlock is presented.By extending the distinguisher,related-key impossible differen-tial attacks on 23-round LBlock and 24-round LBlock are presented.The data complexities of the attacks are 265.2 and 265.6 chosen-plain-text,respectively;the computing complexities of the attacks are 266.2 23-round LBlock encryptions and 266.6 24-round LBlock encryptions,respectively;the storage complexities of the attacks are 261 .2 and 277.2 bytes of memory space,respectively.The crypt-analysis of reduced-round LBlock are first extended to 23-round and 24-round in this paper.
出处
《电子学报》
EI
CAS
CSCD
北大核心
2015年第10期1948-1953,共6页
Acta Electronica Sinica
基金
国家自然科学基金(No.61272488)
博士后科学基金(No.2014M562582)
