摘要：

通过分析流密码算法SOSEMANUK的一个设计弱点，提出一种针对SOSEMANUK密钥流生成器的猜测-确定攻击。该攻击只需要猜测7个32 bit内部状态变量，就可以确定唯一的12个状态变量，攻击算法只需要6个密钥字且计算复杂度为O(2196)。攻击结果表明，该设计存在安全漏洞，SOSEMANUK抗猜测-确定攻击的计算复杂度远低于O(2256)。

关键词: 流密码, SOSEMANUK算法, 猜测-确定攻击, 密钥流

Abstract:

By analyzing the weakness in design of the stream cipher SOSEMANUK, this paper presents Guess and Determine on it. It guesses 7-words internal state, each word contains 32 bit, and then all the internal state can be achieved, the process requires only 6 keystream words. Guess and Determine attack on the cipher is introduced with a computational complexity of O(2196). The results show that the equation which is analyzed exists security vulnerabilities, moreover the computational complexity of attack is far lower than O(2256).

Key words: stream cipher, SOSEMANUK algorithm, Guess and Determine attack, keystream

中图分类号: 

• TN918.1