Quantum Distinguishing Attacks against Type-1 Generalized Feistel Ciphers

Gembu Ito; Tetsu Iwata

Paper 2019/327

Quantum Distinguishing Attacks against Type-1 Generalized Feistel Ciphers

Gembu Ito and Tetsu Iwata

Abstract

A generalized Feistel cipher is one of the methods to construct block ciphers, and it has several variants. Dong, Li, and Wang showed quantum distinguishing attacks against the $(2d-1)$-round Type-1 generalized Feistel cipher with quantum chosen-plaintext attacks, where $d\ge 3$, and they also showed key recovery attacks [Dong, Li, Wang. Sci China Inf Sci, 2019, 62(2): 022501]. In this paper, we show a polynomial time quantum distinguishing attack against the $(3d-3)$-round version, i.e., we improve the number of rounds by $(d-2)$. We also show a quantum distinguishing attack against the $(d^2-d+1)$-round version in the quantum chosen-ciphertext setting. We apply these quantum distinguishing attacks to obtain key recovery attacks against Type-1 generalized Feistel ciphers.

Metadata

Available format(s): PDF
Category: Secret-key cryptography
Publication info: Preprint. MINOR revision.
Keywords: Generalized Feistel cipher Simon's algorithm Grover search Quantum cryptanalysis
Contact author(s): tetsu iwata @ nagoya-u jp
History: 2019-03-29: received
Short URL: https://ia.cr/2019/327
License: CC BY

BibTeX

@misc{cryptoeprint:2019/327,
      author = {Gembu Ito and Tetsu Iwata},
      title = {Quantum Distinguishing Attacks against Type-1 Generalized Feistel Ciphers},
      howpublished = {Cryptology {ePrint} Archive, Paper 2019/327},
      year = {2019},
      url = {https://eprint.iacr.org/2019/327}
}