Je recherche

722 résultats

• • Séminaire

  • Cryptographie

  Cryptography based on rank metric codes

  • 08 novembre 2019

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

  Orateur : Nicolas Aragon - Université de Limoges, exceptionnellement salle Jersey à l'ISTIC

  In the past few years, the interest for rank metric based cryptography has drastically increased, especially since the beginning of the NIST Post-Quantum Cryptography standardization process : five rank metric based proposals were submitted to the first round. This talk will present the different approaches and tradeoffs for building Key Encapsulation Mechanisms and Public Key Encryption schemes[…]

• • Séminaire

  • Cryptographie

  Key Reinstallation Attacks: Forcing Nonce Reuse in WPA2

  • 23 mars 2018

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

  Orateur : Mathy Vanhoef - KU-Leuven

  We introduce key reinstallation attacks (KRACKs). These attacks abuse features of a protocol to reinstall an already in-use key, thereby resetting nonces and/or replay counters associated to this key. We show that our novel attack technique breaks several handshakes that are used in a WPA2-protected network.<br/> All protected Wi-Fi networks use the 4-way handshake to generate fresh session keys.[…]

• • Séminaire

  • Cryptographie

  Designing and deploying post-quantum cryptography

  • 08 mars 2019

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

  Orateur : Jean-Philippe Aumasson - Teserakt AG

  I will review the hash-based signature submitted to the NIST competition jointly with Guillaume Endignoux, discussing its assurance level and performance. Then I will discuss the challenges of deploying post-quantum cryptography in an end-to-end encryption product for machine-to-machine communications.<br/> lien: http://desktop.visio.renater.fr/scopia?ID=721783***6864&autojoin

• • Séminaire

  • Cryptographie

  Attaques sur des conversions IND-CCA de systèmes basés sur les codes

  • 24 mars 2017

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

  Orateur : Paul Stankovski - Université de Lund

  Algorithms for secure encryption in a post-quantum world are currently receiving a lot of attention in the research community, including several larger projects and a standardization effort from {NIST}. One of the most promising algorithms is the code-based scheme called QC-MDPC, which has excellent performance and a small public key size.<br/> In this work we present a very efficient key recovery[…]

• • Séminaire

  • Cryptographie

  Class Group Computations in Number Fields and Applications to Cryptology

  • 08 décembre 2017

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

  Orateur : Alexandre Gelin - Versailles-Saint-Quentin-en-Yvelines

  In this talk, we focus on class group computations in number fields. We start by describing an algorithm for reducing the size of a defining polynomial of a number field. There exist infinitely many polynomials that define a specific number field, with arbitrarily large coefficients, but our algorithm constructs the one that has the absolutely smallest coefficients. The advantage of knowing such a[…]

• • Séminaire

  • Cryptographie

  Design de cryptographie white-box : n'oublions pas la grey-box

  • 02 décembre 2016

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

  Orateur : Philippe Teuwen - QuarksLab

  Bien que toutes les tentatives académiques actuelles pour créer des primitives cryptographiques standard en white-box aient été cassées, il y a encore un grand nombre d'entreprises qui vendent des solutions "sécurisées" de cryptographie white-box. Afin d'évaluer le niveau de sécurité de solutions en boîte blanche, nous verrons de nouvelles approches qui ne nécessitent ni connaissance des tables[…]