CLEFIA密码的Square攻击  

Square Bttack on CLEFIA

作　　者：唐学海[1] 李超[1,2] 谢端强[1] 

机构地区：[1]国防科技大学数学与系统科学系,长沙410073 [2]东南大学移动通信国家重点实验室,南京210096

出　　处：《电子与信息学报》2009年第9期2260-2263,共4页Journal of Electronics & Information Technology

基　　金：国家自然科学基金(60803156;60573028);东南大学移动通信国家重点实验室开放基金(w200805)资助课题

摘　　要：该文根据CLEFIA密码的结构特性,得到了Square攻击的新的8轮区分器,并指出了设计者提出的错误8轮区分器。利用新的8轮区分器对CLEFIA密码进行了10到12轮的Square攻击,攻击结果如下:攻击10轮CLEFIA-128\192\256的数据复杂度和时间复杂度分别为297和292.7;攻击11轮CLEFIA-192\256的数据复杂度和时间复杂度分别为298和2157.6;攻击12轮CLEFIA-256的数据复杂度和时间复杂度分别为298.6和2222。攻击结果表明:在攻击10轮CLEFIA时,新的Square攻击在数据复杂度和时间复杂度都优于设计者给出的Square攻击。According to the structure properties of CLEFIA , new 8-round distinguishers for Square attack are presented, and the wrong 8-round distinguishers originally found by the designers are pointed out. Based on the new distinguisher, the square attack on CLEFIA can be improved as follows： 10-round CLEFIA-128／192／256 is attacked with data complexity 2^97 and time complexity 2^92.7, 11-round CLEFIA-192/256 is attacked with data complexity 2^98 and time complexity 2^157.6, and 12-round CLEFIA-256 is breakable with data complexity 2^98.6 and time complexity 2^222. These results demonstrate that under the case of 10-round CLEFIA, both data and time complexity of our attack are better than those given by the designers.

关 键 词：密码 CLEFIA 区分器 SQUARE攻击 

分 类 号：TN918.1[电子电信—通信与信息系统]