Towards Key-Dependent Integral and Impossible Differential Distinguishers on 5-Round AES

Kai Hu; Tingting Cui; Chao Gao; Meiqin Wang

Paper 2018/726

Towards Key-Dependent Integral and Impossible Differential Distinguishers on 5-Round AES

Kai Hu, Tingting Cui, Chao Gao, and Meiqin Wang

Abstract

Reduced-round AES has been a popular underlying primitive to design new cryptographic schemes and thus its security including distinguishing properties deserves more attention. At Crypto'16, a key-dependent integral distinguisher on 5-round AES was put forward, which opened up a new direction to take more insights into the distinguishing properties of AES. After that, two key-dependent impossible differential (ID) distinguishers on 5-round AES were proposed at FSE'16 and CT-RSA'18, respectively. It is strange that the current key-dependent integral distinguisher requires significantly higher complexities than the key-dependent ID distinguishers, even though they are constructed with the same property of MixColumns (). Proposers of the 5-round key-dependent distinguishers claimed that the corresponding integral and ID distinguishers can only work under chosen-ciphertext and chosen-plaintext settings, respectively, which is very different from the situations of traditional key-independent distinguishers. In this paper, we first construct a novel key-dependent integral distinguisher on 5-round AES with chosen plaintexts, which is much better than the previous key-dependent integral distinguisher that requires the full codebook proposed at Crypto'16. Secondly, we show that both distinguishers are valid under either chosen-plaintext setting or chosen-ciphertext setting, which is different from the claims of previous cryptanalysis. However, under different settings, complexities of key-dependent integral distinguishers are very different while those of the key-dependent ID distinguishers are almost the same. We analyze the reasons for it.

Metadata

Available format(s): PDF
Category: Secret-key cryptography
Publication info: Published elsewhere. SAC 2018
Keywords: AES Key-Dependent Integral Impossible Differential
Contact author(s): mqwang @ sdu edu cn
History: 2018-08-09: received
Short URL: https://ia.cr/2018/726
License: CC BY

BibTeX

@misc{cryptoeprint:2018/726,
      author = {Kai Hu and Tingting Cui and Chao Gao and Meiqin Wang},
      title = {Towards Key-Dependent Integral and Impossible Differential Distinguishers on 5-Round {AES}},
      howpublished = {Cryptology {ePrint} Archive, Paper 2018/726},
      year = {2018},
      url = {https://eprint.iacr.org/2018/726}
}