CRYSTALS-Dilithium: A Lattice-Based Digital Signature Scheme

  • Léo Ducas CWI
  • Eike Kiltz Ruhr Universität Bochum
  • Tancrède Lepoint SRI International
  • Vadim Lyubashevsky IBM Research – Zurich
  • Peter Schwabe Radboud University
  • Gregor Seiler IBM Research – Zurich
  • Damien Stehlé ENS de Lyon
Keywords: Lattice Cryptography, Digital Signatures, Constant-Time Implementation, AVX2

Abstract

In this paper, we present the lattice-based signature scheme Dilithium, which is a component of the CRYSTALS (Cryptographic Suite for Algebraic Lattices) suite that was submitted to NIST’s call for post-quantum cryptographic standards. The design of the scheme avoids all uses of discrete Gaussian sampling and is easily implementable in constant-time. For the same security levels, our scheme has a public key that is 2.5X smaller than the previously most efficient lattice-based schemes that did not use Gaussians, while having essentially the same signature size. In addition to the new design, we significantly improve the running time of the main component of many lattice-based constructions – the number theoretic transform. Our AVX2-based implementation results in a speed-up of roughly a factor of 2 over the previously best algorithms that appear in the literature. The techniques for obtaining this speed-up also have applications to other lattice-based schemes.
Published
2018-02-14
How to Cite
Ducas, L., Kiltz, E., Lepoint, T., Lyubashevsky, V., Schwabe, P., Seiler, G., & Stehlé, D. (2018). CRYSTALS-Dilithium: A Lattice-Based Digital Signature Scheme. IACR Transactions on Cryptographic Hardware and Embedded Systems, 2018(1), 238-268. https://doi.org/10.13154/tches.v2018.i1.238-268
Section
Articles