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arXiv · 0912.1918

Optimal quantitative cryptanalysis of permutation-only multimedia ciphers against plaintext attacks

Chengqing Li·Kwok-Tung Lo
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Abstract

Recently, an image scrambling encryption algorithm of pixel bit based on chaos map was proposed. Considering the algorithm as a typical binary image scrambling/permutation algorithm exerting on plaintext of size $M\times (8N)$, this paper proposes a novel optimal method to break it with some known/chosen-plaintexts. The spatial complexity and computational complexity of the attack are only $O(32\cdot MN)$ and $O(16\cdot n_0\cdot MN)$ respectively, where $n_0$ is the number of known/chosen-plaintexts used. The method can be easily extended to break any permutation-only encryption scheme exerting on plaintext of size $M\times N$ and with $L$ different levels of values. The corresponding spatial complexity and computational complexity are only $O(MN)$ and $O(\lceil\log_L(MN)\rceil \cdot MN)$ respectively. In addition, some specific remarks on the performance of the image scrambling encryption algorithm are presented.

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Chengqing Li, Kwok-Tung Lo. 2016-09-21. Optimal quantitative cryptanalysis of permutation-only multimedia ciphers against plaintext attacks. https://doi.org/10.1016/j.sigpro.2010.09.014

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