698 résultats

  • PMNS for efficient arithmetic and small memory cost

    • 10 juin 2022

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

    Orateur : Fangan Yssouf Dosso - Ecole des Mines de Saint-Etienne

    The Polynomial Modular Number System (PMNS) is an integer number system which aims to speed up arithmetic operations modulo a prime p. Such a system is defined by a tuple (p, n, g, r, E), where p, n, g and r are positive integers, E is a monic polynomial with integer coefficients, having g as a root modulo p. Most of the work done on PMNS focus on polynomials E such that E(X) = X^n – l, where l is[…]
  • Syndrome Decoding in the Head – Shorter Signatures from Zero-Knowledge proofs

    • 10 juin 2022

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

    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[…]
  • Isogenies over Hessian Model of Elliptic Curves

    • 03 juin 2022

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

    Orateur : Emmanuel Fouotsa - Université de Bamenda

    In this talk we present explicit formulas for isogenies between elliptic curves in (twisted) Hessian form. We examine the numbers of operations in the base field to compute the formulas. In comparison with other isogeny formulas, we note that the obtained formulas for twisted Hessian curves have the lowest costs for processing the kernel and the X-affine formula has the lowest cost for processing[…]
  • New uses in Symmetric Cryptography: from Cryptanalysis to Designing

    • 20 mai 2022

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

    Orateur : Clémence Bouvier - INRIA

    New symmetric primitives are being designed to be run in abstract settings such as Multi-Party Computations (MPC) or Zero-Knowledge (ZK) proof systems. More particularly, these protocols have highlighted the need to minimize the number of multiplications performed by the primitive in large finite fields.<br/> As the number of such primitives grows, it is important to better understand the[…]
  • Port Contention Goes Portable: Port Contention Side Channels in Web Browsers

    • 13 mai 2022

    • Inria Center of the University of Rennes - - See the page of each talk for the room.

    Orateur : Thomas Rokicki (Univ Rennes, CNRS, IRISA)

    Microarchitectural side-channel attacks can derive secrets from the execution of vulnerable programs. Their implementation in web browsers represents a considerable extension of their attack surface, as a user simply browsing a malicious website, or even a malicious third-party advertisement in a benign cross-origin isolated website, can be a victim.In this talk, we present the first CPU port[…]
  • Side Channel Analysis: Instruction extraction and Information estimation

    • 06 mai 2022

    • CEA-LETI; Université de Montpellier, LIRMM - Salle Pétri/Turing

    Orateur : Valence Cristiani

    Side-channel usually aims at extracting cryptographic secrets from electronic devices through their physical leakages. However, these channels can leak other sensitive information. The first part of this talk will present a study of side channel-based disassembling (SCBD) that aims to recover instructions executed by a microcontroller. The main threat represented by SCBD is that it potentially[…]