Cryptology ePrint Archive: Report 2017/1194

Improved Differential Cryptanalysis on Generalized Feistel Schemes

Ivan Tjuawinata and Tao Huang and Hongjun Wu

Abstract: Nachef et al used differential cryptanalysis to study four types of Generalized Feistel Scheme (GFS). They gave the lower bound of maximum number of rounds that is indistinguishable from a random permutation. In this paper, we study the security of several types of GFS by exploiting the asymmetric property. We show that better lower bounds can be achieved for the Type-1 GFS, Type-3 GFS and Alternating Feistel Scheme. Furthermore, we give the first general results regarding to the lower bound of the Unbalanced Feistel Scheme.

Category / Keywords: secret-key cryptography / Generalized Feistel Network, Differential Analysis, Chosen Ciphertext Attack, Known Plaintext Attack.

Original Publication (with minor differences): Indocrypt 2017

Date: received 10 Dec 2017

Contact author: s120015 at e ntu edu sg

Available format(s): PDF | BibTeX Citation

Short URL: ia.cr/2017/1194

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