【摘要】 对PFTL图像加密算法的安全性进行了分析,发现其存在信息泄漏规律,并基于此给出了攻击算法.利用图像像素置乱密钥与像素灰度值扩散密钥无关这个弱点进行了分割攻击,在已知明文图像的条件下,给出了在不同迭代圈数下的攻击算法,并对攻击算法的有效性进行了分析.由于原文中对算法的描述存在错误,因此本文给出了正确的灰度值扩散算法及密钥参数,以及通过试验得出了正确的密钥空间,分析结果表明算法的安全性远远低于设计目标.更多还原

【Abstract】 The security of PFTL image encryption scheme is studied,and the attack algorithm is put forward based on the information leakges in the scheme.Specifically,considering the weakness that the key used in confusion has no relation to the key used in diffusion,we put forward divide-and-conquer attack of different circles by using some known-plaintext images,and the efficiency analysis is given.Some mistakes in the original encryption scheme are revised,correct gray value diffusion algorithm and key parameters are given,and correct key space are obotained with an operating experiment.The analysis shows that the security of the encryption algorithm doesn’t reach the design target.更多还原