Improved Attacks on sLiSCP Permutation and Tight Bound of Limited Birthday Distinguishers

  • Akinori Hosoyamada NTT Secure Platform Laboratories, Tokyo, Japan; Nagoya University, Nagoya, Japan
  • María Naya-Plasencia Inria, Paris, France
  • Yu Sasaki NTT Secure Platform Laboratories, Tokyo, Japan
Keywords: limited birthday distinguisher, sLiSCP, permutation, NIST Lightweight cryptography, rebound attack

Abstract

Limited birthday distinguishers (LBDs) are widely used tools for the cryptanalysis of cryptographic permutations. In this paper we propose LBDs on several variants of the sLiSCP permutation family that are building blocks of two round 2 candidates of the NIST lightweight standardization process: Spix and SpoC. We improve the number of steps with respect to the previously known best results, that used rebound attack. We improve the techniques used for solving the middle part, called inbound, and we relax the external conditions in order to extend the previous attacks. The lower bound of the complexity of LBDs has been proved only against functions. In this paper, we prove for the first time the bound against permutations, which shows that the known upper bounds are tight.

Published
2020-12-10
How to Cite
Hosoyamada, A., Naya-Plasencia, M., & Sasaki, Y. (2020). Improved Attacks on sLiSCP Permutation and Tight Bound of Limited Birthday Distinguishers. IACR Transactions on Symmetric Cryptology, 2020(4), 147-172. https://doi.org/10.46586/tosc.v2020.i4.147-172
Section
Articles