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arXiv · 1010.1624

Quantum Generic Attacks on Feistel Schemes

Hong Wang·Zhi Ma
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Abstract

The Feistel scheme is an important structure in the block ciphers. The security of the Feistel scheme is related to distinguishability with a random permutation. In this paper, efficient quantum algorithms for distinguishing classical 3,4-round and unbalanced Feistel scheme with contracting functions from random permutation are proposed. Our algorithms realize an exponential speed-up over classical algorithms for these problems. Furthermore, the method presented in this paper can also be used to consider unbalanced Feistel schemes with expanding functions.

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Hong Wang, Zhi Ma. 2010-10-08. Quantum Generic Attacks on Feistel Schemes. https://arxiv.org/abs/1010.1624

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