Sommaire

  • Cet exposé a été présenté le 10 juin 2022.

Description

  • Orateur

    Thibauld Feneuil - CryptoExperts et Sorbonne Université

In this talk, I will present a new zero-knowledge proof of knowledge for the syndrome decoding (SD) problem on random linear codes. Instead of using permutations like most of the existing protocols, we rely on the MPC-in-the-head paradigm in which we reduce the task of proving the low Hamming weight of the SD solution to proving some relations between specific polynomials. Specifically, we propose a 5-round zero-knowledge protocol that proves the knowledge of a vector x such that y=Hx and wt(x)<= w and which achieves a soundness error closed to 1/N for an arbitrary N.<br/> While turning this protocol into a signature scheme, we achieve a signature size of 11-12 KB for 128-bit security when relying on the hardness of the SD problem on binary fields. Using larger fields (like F_{256}), we can produce fast signatures of around 8 KB. This allows us to outperform Picnic3 and to be competitive with SPHINCS+, both post-quantum signature candidates in the ongoing NIST standardization effort. Since the security relies on the hardness of the syndrome decoding problem for random linear codes which is known to be NP-hard and for which the cryptanalysis state of the art has been stable for many years, it results in a conservative signature scheme. Moreover, our scheme outperforms all the existing code-based signature schemes for the common « signature size + public key size » metric.<br/> Joint work with Antoine Joux and Matthieu Rivain.<br/> lien: https://seminaire-c2.inria.fr/

Prochains exposés

  • Polytopes in the Fiat-Shamir with Aborts Paradigm

    • 29 novembre 2024 (13:45 - 14:45)

    • IRMAR - Université de Rennes - Campus Beaulieu Bat. 22, RDC, Rennes - Amphi Lebesgue

    Orateur : Hugo Beguinet - ENS Paris / Thales

    The Fiat-Shamir with Aborts paradigm (FSwA) uses rejection sampling to remove a secret’s dependency on a given source distribution.&nbsp; Recent results revealed that unlike the uniform distribution in the hypercube, both the continuous Gaussian and the uniform distribution within the hypersphere minimise the rejection rate and the size of the proof of knowledge. However, in practice both these[…]
    • Cryptographie

    • Primitive asymétrique

    • Mode et protocole

  • Post-quantum Group-based Cryptography

    • 20 décembre 2024 (13:45 - 14:45)

    • IRMAR - Université de Rennes - Campus Beaulieu Bat. 22, RDC, Rennes - Amphi Lebesgue

    Orateur : Delaram Kahrobaei - The City University of New York

Voir les exposés passés