LBlock算法的相关密钥不可能飞来去器分析  

Related-key impossible boomerang cryptanalysis on LBlock

作　　者：谢敏[1] 牟彦利 

机构地区：[1]西安电子科技大学综合业务网理论及关键技术国家重点实验室,陕西西安710071

出　　处：《通信学报》2017年第5期66-71,共6页Journal on Communications

基　　金：国家自然科学基金资助项目(No.61373170;No.U0835004;No.U1536202);国家111创新引智基金资助项目(No.B08038)~~

摘　　要：研究了相关密钥不可能飞来去器分析方法及轻量级分组密码算法LBlock在该分析方法下的安全性。将不可能飞来去器分析方法和相关密钥分析方法相结合,针对22轮LBlock给出了新的攻击。构造了15轮的相关密钥不可能飞来去器区分器,通过向前扩展3轮,向后扩展4轮,成功攻击了22轮LBlock。该攻击的数据复杂度仅为2^(51.3)个明文,计算复杂度为2^(71.54)次22轮加密。与已有结果相比,攻击的数据复杂度和计算复杂度均有明显下降。The related-key impossible boomerang cryptanalysis and the strength of the lightweight block cipher LBlock against this method were investigated. A new attack on 22-round LBlock was presented combining impossible boomerang attacks with related-key attacks. A 15-round related-key impossible boomerang distinguisher was constructed. Based on the new distinguisher, an attack on 22-round LBlock was mounted successfully by concatenating 3-round to the begin- ning and 4-round to the end. The attack on 22-round LBlock required data complexity of only 2 513 plaintexts and com- putational complexity of about 2 7154 22-round encryptions. Compared with published cryptanalysis results on 22-round LBlock, proposed attack has great advantages on data and computational complexities.

关 键 词：LBlock算法 轻量级分组密码 相关密钥 不可能飞来去器 

分 类 号：TN918.1[电子电信—通信与信息系统]