• 中国计算机学会会刊
  • 中国科技核心期刊
  • 中文核心期刊

J4 ›› 2012, Vol. 34 ›› Issue (6): 28-31.

• 论文 • 上一篇    下一篇

对简化轮数的SNAKE(2)算法的中间相遇攻击

魏悦川1,孙兵2,李超1,2,3   

  1. (1.国防科学技术大学计算机学院,湖南 长沙 410073; 2.国防科学技术大学理学院,湖南 长沙 410073;
    3.中国科学院信息安全国家重点实验室,北京 100049)
  • 收稿日期:2010-04-30 修回日期:2010-09-25 出版日期:2012-06-25 发布日期:2012-06-25
  • 基金资助:

    国家自然科学基金资助项目(60803156);信息安全国家重点实验室开放基金资助项目(0107)

A MeetintheMiddle Attack on ReducedRound SNAKE(2)

WEI Yuechuan1,SUN Bing2,LI Chao1,2,3   

  1. (1.School of Computer Science,National University of Defense Technology,Changsha 410073;
    2.School of Science,National University of Defense Technology,Changsha 410073;
    3.State Key Laboratory of Information Security,Chinese Academy of Sciences,Beijing 100049,China)
  • Received:2010-04-30 Revised:2010-09-25 Online:2012-06-25 Published:2012-06-25

摘要:

SNAKE算法是由Lee等学者在JWISC 1997上提出的一个Feistel型分组密码,有SNAKE(1)和SNAKE(2)两个版本。本文评估了简化轮数的SNAKE(2)算法对中间相遇攻击的抵抗能力,用存储复杂度换取时间复杂度,对7/8/9轮64比特分组的SNAKE(2)算法实施了攻击。攻击结果表明,9轮的SNAKE(2)算法对中间相遇攻击是不抵抗的,攻击的数据复杂度和时间复杂度分别为211.2和222,预计算复杂度为 232,是现实攻击。

关键词: 分组密码, 中间相遇攻击, SNAKE(2), 攻击复杂度

Abstract:

SNAKE is a Feistel cipher proposed by Lee and Cha at JWISC 1997. It has two versions, i.e. SNAKE(1) and SNAKE(2). The security of the reducedround SNAKE(2) against meetinthemiddle attacks is evaluated in this paper. Attacks on 7/8/9 rounds SNAKE(2) with a 64bit block are performed. The result shows that SNAKE(2) reduced to 9 rounds is not immune to meetinthemiddle attacks. The data complexity, time complexity and precomputation complexity are 211.2,222 and  232 respectively, which implies a real world attack.

Key words: block cipher;meetinthemiddle attack;SNAKE(2);attack complexity