摘要： 对复合混沌伪随机序列加密算法(CCPRSEA)做了深入分析，通过对该算法中素域上线性同余变换的分析，分离出混沌序列，利用混沌映射自身的信息泄漏规律，给出基于吻合度分布规律和函数中值定理的分割攻击方法，在base=10, m=3的情况下，证明了破译算法的成功率为0.982 7，计算复杂性为240。实验表明，在主频为2.5GHz的Pentium 4 PC上，求出其全部密钥的整个攻击时间只需8h35min，因此，CCPRSEA是不安全的。

关键词: 混沌密码, 序列密码, 分割攻击, 已知明文攻击, logistics映射, 线性同余变换

Abstract: This paper analyzes the composite chaotic pseudo-random sequence encryption algorithm(CCPRSEA). By analyzing the linear congruent algorithm on a prime field of CCPRSEA, it gains chaotic sequence and gives a tally-degree-based divide-and-conquer attack algorithm by using the information leak of the chaotic map itself. When base=10 and m=3, it proves that the success rate of the attack algorithm is 0.982 7 and the complexity is 240. Experimental results indicate that it just needs 8 hours and 35 minutes for attacking all keys of CCPRSEA in 2.5GHz of Pentium 4 PC. So CCPRSEA is insecure.

Key words: chaotic cipher, stream cipher, divide-and-conquer attack, known plaintexts attack, logistics mapping, linear congruent algorithm

中图分类号: 

• TN918