一类改进的混沌迭代加密算法

An improved block cryptosystem based on iterating chaotic map

指出了最近提出的一类混沌迭代分组密码算法的缺陷,通过选择明文攻击可以恢复出置换后的明文.算法中二进制序列的产生只依赖于密钥,而与明文无关,从而使算法容易造成信息泄露并遭受攻击.基于此,给出了一种可以抵御选择明文攻击的安全性更高的算法.

Recently, a large number of chaotic cryptosystems have been proposed, yet many of them have the drawbacks of lack of robustness and security. In this paper, we point out the weakness of a very recent block cipher algorithm which is based on the chaotic map and give the improved scheme of it. We provide the chosen plaintext attack to recover the permuted plaintext string. It is shown that the generation mechanism of binary sequences which depends on the key but not on the plaintext facilitates leakage of information and is vulnerable to attacks. Based on such a fact, we give the improved scheme to achieve higher security.