Zhu Congxu, Wang Guojun, Sun Kehui
School of Information Science and Engineering, Central South University, Changsha 410083, China.
School of Computer Science and Technology, Guangzhou University, Guangzhou 510006, China.
Entropy (Basel). 2018 Nov 3;20(11):843. doi: 10.3390/e20110843.
This paper presents an improved cryptanalysis of a chaos-based image encryption scheme, which integrated permutation, diffusion, and linear transformation process. It was found that the equivalent key streams and all the unknown parameters of the cryptosystem can be recovered by our chosen-plaintext attack algorithm. Both a theoretical analysis and an experimental validation are given in detail. Based on the analysis of the defects in the original cryptosystem, an improved color image encryption scheme was further developed. By using an image content-related approach in generating diffusion arrays and the process of interweaving diffusion and confusion, the security of the cryptosystem was enhanced. The experimental results and security analysis demonstrate the security superiority of the improved cryptosystem.
本文提出了一种对基于混沌的图像加密方案的改进密码分析方法，该方案集成了置换、扩散和线性变换过程。研究发现，通过我们选择明文攻击算法可以恢复密码系统的等效密钥流和所有未知参数。详细给出了理论分析和实验验证。基于对原密码系统缺陷的分析，进一步开发了一种改进的彩色图像加密方案。通过在生成扩散阵列以及交织扩散和混淆过程中使用与图像内容相关的方法，增强了密码系统的安全性。实验结果和安全性分析证明了改进后密码系统的安全优越性。
