6.1.1 Belenios

• Name:
  Belenios - Verifiable online voting system
• Keyword:
  E-voting
• Functional Description:

  Belenios is an open-source online voting system that provides vote confidentiality and verifiability. End-to-end verifiability relies on the fact that the ballot box is public (voters can check that their ballots have been received) and on the fact that the tally is publicly verifiable (anyone can recount the votes). Vote confidentiality relies on the encryption of the votes and the distribution of the decryption key (no one detains the secret key).

  Belenios supports various kind of elections. In the standard mode, Belenios supports simple elections where voters simply select one or more candidates. It also supports arbitrary counting functions at the cost of a slightly more complex tally procedure for the authorities. For example, Belenios supports Condorcet, STV, and Majority Judgement, where voters rank candidates and grade them.

  Belenios is available in several languages for the voters as well as the administrators of an election. More languages can be freely added by users.

• News of the Year:

  In 2022, our platform was used to run about 1400 elections, with about 50,000 ballots counted.

  This year we released a major update of Belenios (2.0) that introduces a new election format where election events (e.g., ballot submission) are chained to each other. This sets the stage for a future release where the server will be able to commit to the actual content of an election. We have also improved the monitoring of the server (eg by making the voting authority code constant) and we have initiated compliance with the CNIL recommendations. We have hardened the security of Belenios by linking a voter to the public part of their voting code from the setup phase. To ensure better availability, Belenios is now hosted on OVH servers. Finally, we have pursued the development of the REST API in preparation of a major overhaul of the election administration interface.

• URL:
  https://­www.­belenios.­org/
• Contact:
  Stephane Glondu
• Participants:
  Pierrick Gaudry, Stephane Glondu, Véronique Cortier
• Partners:
  CNRS, Inria

6.1.2 CADO-NFS

• Name:
  Crible Algébrique: Distribution, Optimisation - Number Field Sieve
• Keywords:
  Cryptography, Number theory
• Functional Description:
  CADO-NFS is a complete implementation in C/C++ of the Number Field Sieve (NFS) algorithm for factoring integers and computing discrete logarithms in finite fields. It consists in various programs corresponding to all the phases of the algorithm, and a general script that runs them, possibly in parallel over a network of computers.
• News of the Year:

  In 2022, Cado-NFS evolved in the form of preparatory work for further computations. In particular, work has been done in order to make it possible to run Cado-NFS on small Docker containers, which is a useful first step towards easy deployment on various kinds of cloud-scale computing infrastructures, using engines such as Kubernetes, for example.

  Furthermore, work towards some of the ideas in the context of the Kleptomaniac ANR project is ongoing within Cado-NFS, and will continue in 2023.

• URL:
  https://­cado-nfs.­inria.­fr/
• Contact:
  Emmanuel Thomé
• Participants:
  Pierrick Gaudry, Emmanuel Thomé, Paul Zimmermann

6.1.3 Drinfeld modules in SageMath

• Keywords:
  Computer algebra, Number theory
• Functional Description:

  This project is an implementation, starting from scratch, of Drinfeld modules in SageMath. This module shall be integrated into SageMath.

  Drinfeld modules are mathematical objects similar to elliptic curves, but in another setting, which is that of function fields.

  The aim of this implementation is to provide researchers with all basic computational tools for Drinfeld modules, and to build a reliable basis for future, more sophisticated algorithms.

• URL:
  https://­trac.­sagemath.­org/­ticket/­33713
• Author:
  Antoine Leudière
• Contact:
  Antoine Leudière

6.1.4 snark-2-chains

• Name:
  Families of SNARK-friendly 2-chains of elliptic curves
• Keywords:
  Cryptography, Cryptocurrency, Blockchain
• Functional Description:
  This library implements finite field and elliptic curve arithmetic for BN curves (Barreto-Naehrig), BLS (Barreto-Lynn-Scott), KSS (Kachisa-Schaefer-Scott), and 2-chains made of BW6 (Brezing-Weng curves of embedding degree 6), CP8, CP12 (Cocks-Pinch curves of embedding degree 8 and 12) for use with zk-snarks (zero-knowledge succinct non-interactive argument of knowledge). The cryptographic applications are: pairing, scalar multiplication on the curves, hashing on the curves. The code is a proof of concept tied to two papers and is not optimized.
• News of the Year:
  The library was first released in October 2021 as companion code of the EUROCRYPT'2022 paper. In 2022, state-of-the-art pairing computation on KSS16 and KSS18 curves was developed (known as "optimal-ate" pairing), together with state-of-the-art final exponentiation, according to the latest preprints on the topic. Support for BN curves, BLS 21 and BLS27, FST 6.4 (curves with embedding degrees 20 and 28 and j-invariant 1728) was developed. Formulas from Costello, Lange and Naehrig at PKC'2010 were implemented for cubic twists and quartic twists. Testing and documentation were extended. As companion code of the survey paper at DCC, it now includes faster final exponentiation for outer curves BW6 of 2-chains made of an inner BN, BLS12 or BLS24 curve. Finally it provides a basic support for Remi Clarisse curves BW13 and BW19 of prime embedding degree.
• URL:
  https://­gitlab.­inria.­fr/­zk-curves/­snark-2-chains
• Publications:
  hal-03667798, hal-03371573
• Contact:
  Aurore Guillevic

6.1.5 TNFS-alpha

• Name:
  alpha for the Tower Number Field Sieve algorithm
• Keyword:
  Cryptography
• Functional Description:
  This library implements a simulation tool for the tower number field sieve algorithm computing discrete logarithms in extension fields of small degree (tested up to 54). The library contains an implementation of the exact computation of alpha, the bias between the expected smoothness of an integer and the expected smoothness of a norm of an algebraic integer in a number field made of two extensions. The algorithm is a generalization to extensions of the exact implementation of alpha in the software CADO-NFS. The software contains an implementation of the E-function of B. A. Murphy (Murphy's E) which estimates the quality of the polynomial selection step in TNFS through a simulation of the yield of the relation collection in the TNFS algorithm. Finally it contains a database of pairing-friendly curve seeds with the estimated level of security w.r.t a discrete logarithm computation in the corresponding finite field.
• News of the Year:
  In 2022 support was included to generate sparse seeds of pairing-friendly curves with many more curve families, and with specific needs for SNARKs such as a large power of 2 dividing the predecessor of the characteristic, or dividing the predecessor of the order, or both conditions at the same time. Now it supports BN curves, all BLS curves, all KSS curves, Aurifeuillean curves, Fotiadis-Martindale curves, Freeman-Scott-Teske curves and allows generating seeds producing FFT-friendly fields. Galbraith-McKee-Valença curves were included as special cases of MNT curves. The security level of these curves was estimated for the DCC survey paper. For TNFS simulation, precomputed tables of sparse irreducible polynomials of degree 18, 20, 24 were released to estimate the security of KSS18, BLS24, and FST6.4 k=20 curves.
• URL:
  https://­gitlab.­inria.­fr/­tnfs-alpha/­alpha
• Publications:
  hal-03667798, hal-03371573, hal-02263098, hal-02396352
• Contact:
  Aurore Guillevic

6.1.6 CORE-MATH

• Name:
  CORE-MATH
• Keywords:
  Arithmetic code, Floating-point, Correct Rounding
• Functional Description:
  CORE-MATH Mission: provide on-the-shelf open-source mathematical functions with correct rounding that can be integrated into current mathematical libraries (GNU libc, Intel Math Library, AMD Libm, Newlib, OpenLibm, Musl, Apple Libm, llvm-libc, CUDA libm, ROCm)
• News of the Year:
  In 2022, a full set of C99 single precision functions was designed, and in addition single precision functions from the new C23 standard. Also, a few double precision functions are already available: acos, asin, cbrt, exp, exp2, hypot, log and rsqrt.
• URL:
  https://­core-math.­gitlabpages.­inria.­fr/
• Publication:
  hal-03721525
• Contact:
  Paul Zimmermann

6.1.7 GNU-MPFR

• Keywords:
  Multiple-Precision, Floating-point, Correct Rounding
• Functional Description:
  GNU MPFR is an efficient arbitrary-precision floating-point library with well-defined semantics (copying the good ideas from the IEEE 754 standard), in particular correct rounding in 5 rounding modes. It provides about 100 mathematical functions, in addition to utility functions (assignments, conversions...). Special data (Not a Number, infinities, signed zeros) are handled like in the IEEE 754 standard. GNU MPFR is based on the mpn and mpz layers of the GMP library.
• News of the Year:
  In November 2022, a minor version (4.1.1) was released, with 13 bug fixes with respect to 4.1.0 (released in 2020), various internal changes due to the switch from Subversion to Git and a complete review of the typography of the manual. In early January 2023, a major version (4.2.0) was released, which in particular implements missing functions from the new ISO C23 standard.
• URL:
  https://­www.­mpfr.­org/
• Publications:
  hal-01394289, hal-01502326, inria-00069930, inria-00070174, inria-00103655, inria-00000026
• Contact:
  Vincent Lefèvre
• Participants:
  Guillaume Hanrot, Paul Zimmermann, Philippe Théveny, Vincent Lefèvre

7.1.1 Computing a Group Action from the Class Field Theory of Imaginary Hyperelliptic Function Fields

Participants: Antoine Leudière, Pierre-Jean Spaenlehauer.

In this work 29 we expand the algorithmic toolbox for finite Drinfeld modules by designing algorithms and complexity bounds for the manipulation of isogenies of ordinary Drinfeld modules. This paper is an expanded version of a previous preprint which focused on cryptographic applications. Benjamin Wesolowski found a way to attack our proposed cryptographic applications, this is why this new version of the paper focuses more on purely algorithmic aspects and on effective number theory.

7.1.2 Families of SNARK-friendly 2-chains of elliptic curves

Participants: Aurore Guillevic.

7.1.3 Co-factor clearing and subgroup membership testing on pairing-friendly curves

Participants: Aurore Guillevic.

7.1.4 A survey of elliptic curves for proof systems

Participants: Aurore Guillevic.

7.2.1 State of the art

Participants: Pierrick Gaudry, Aurore Guillevic, Emmanuel Thomé, Paul Zimmermann.

In the invited article 32 in IEEE Security & Privacy, we review the current state of the art of cryptanalysis for three number-theoretic problems using classical (nonquantum) computers, including, in particular, our most recent computational records for integer factoring and prime-field discrete logarithms. This work is connected to our earlier work on factoring and discrete logarithm records, which we put in perspective in the broader context of the assessment of the security of the classical public-key cryptographic primitives. Despite the hype about the future transition to post-quantum cryptographic algorithms, everyone is fully aware of the fact that classical algorithms are here to stay, at least for a long while. It is of utmost importance to properly assess the possible security risk that arises from their continued use.

7.2.2 Algorithmic aspects of elliptic bases in finite field discrete logarithm algorithms

Participants: Cécile Pierrot.

7.2.3 Individual Discrete Logarithm with Sublattice Reduction

Participants: Haetham Al Aswad, Cécile Pierrot.

7.3.1 The CORE-MATH project

Participants: Stéphane Glondu, Paul Zimmermann.

The aim of the CORE-MATH project is to provide on-the-shelf open-source mathematical functions with correct rounding that will be integrated into current mathematical libraries (GNU libc, Intel Math Library, AMD Libm, Newlib, OpenLibm, Musl, Apple Libm, llvm-libc, CUDA libm, ROCm). These functions are implemented in the C language and target the three IEEE 754 binary formats (single precision, double precision, quadruple precision), and also the extended double precision (significand of 64 bits). This project is motivated by the fact that current mathematical libraries are far from giving the best possible results, as demonstrated in 28.

In 2022, with the help of Stéphane Glondu, some tools were set up to assess the correctness of the CORE-MATH functions, and to measure their speed (both reciprocal throughput and latency). These tools are also able to test other mathematical libraries.

In 2022, a full set of C99 single precision (binary32) functions was implemented. In addition, binary32 functions from the new C23 standard were also implemented. The article 22 detailing this work got the Best Paper Award at the Arith'2022 conference. A few double precision (binary64) functions are now available: acos, asin, cbrt, exp, exp2, hypot, log, rsqrt. During his M1 internship, Tom Hubrecht designed an efficient pow function in double precision, which is in review before inclusion into CORE-MATH.

The development of CORE-MATH forced us to revisit some classical algorithms, for example FastTwoSum in the context of directed roundings 31.

Monthly video-conferences are organized with the LLVM developers who also develop correctly-rounded routines, and use the CORE-MATH tools to check their correctness and efficiency.

7.3.2 Search for worst cases

Participants: Paul Zimmermann.

To design correctly-rounded functions as in the CORE-MATH project, it is of utmost importance to know “worst cases” of mathematical functions, i.e., inputs $x$ such that $f\left(x\right)$ has many zeros or ones after the rounding bit. During her M1 internship, Lauriane Turelier extended the SLZ algorithm to bivariate functions, and designed a SageMath implementation of this extension 30.

7.4.1 Automatic Search of Rectangle Attacks on Feistel Ciphers: Application to WARP

Participants: Virginie Lallemand, Marine Minier, Loïc Rouquette.

7.4.2 Benchmarking of lightweight cryptographic algorithms for wireless IoT networks

Participants: Marine Minier.

7.4.3 And Rijndael? Automatic Related-key Differential Analysis of Rijndael

Participants: Loïc Rouquette, Marine Minier.

7.4.4 Non-triangular self-synchronizing stream ciphers

Participants: Paul Huynh, Marine Minier.

7.4.5 Towards a new design of ciphers to secure CPS: the role of control theory

Participants: Hamid Boukerrou, Marine Minier.

Among several solutions to face the unprecedented increase of attacks against Cyber Physical Systems, encryption plays a central role. In the form of a Proof of Concept and in 24, this contribution gives a new methodology for designing self-synchronizing automata, having in mind their use in symmetric cryptography, namely the Self-Synchronizing Stream Ciphers. The contribution of the paper is to recast the design as control theoretical issues. It calls for a graph-based approach and results borrowed from control theory and dynamical systems, in particular LPV systems. The design leads to not necessarily T -functions as state transition functions of the automata involved in the ciphering and deciphering sides. It is a consideration that is important for the sake of security. Another asset of the approach is that the resulting ciphers admit possibly vectorial inputs to enhance the throughput.

7.4.6 Beyond quadratic speedups in quantum attacks on symmetric schemes

Participants: Xavier Bonnetain.

We report in 15 the first quantum key-recovery attack on a symmetric block cipher design, using classical queries only, with a more than quadratic time speedup compared to the best classical attack.

We study the 2XOR-Cascade construction of Gaži and Tessaro (EUROCRYPT 2012). It is a key length extension technique which provides an n-bit block cipher with 5n/2 bits of security out of an n-bit block cipher with 2n bits of key, with a security proof in the ideal model. We show that the offline-Simon algorithm of Bonnetain et al. (ASIACRYPT 2019) can be extended to, in particular, attack this construction in quantum time $O\left(2^n\right)$, providing a $2.5-$th power quantum speedup over the best classical attack.

Regarding post-quantum security of symmetric ciphers, it is commonly assumed that doubling the key sizes is a sufficient precaution. This is because Grover's quantum search algorithm, and its derivatives, can only reach a quadratic speedup at most. Our attack shows that the structure of some symmetric constructions can be exploited to overcome this limit. In particular, the 2XOR-Cascade cannot be used to generically strengthen block ciphers against quantum adversaries, as it would offer only the same security as the block cipher itself.

7.5.1 General audience book on e-voting

Participants: Pierrick Gaudry.

Together with Véronique Cortier (PESTO Team), Pierrick Gaudry wrote a general audience book 33 on various aspects of electronic voting, with an emphasis on security aspects. Written in French, this book was published by Odile Jacob and received a nice press coverage, including an article in Le Monde.

7.5.2 Coercion-resistance

Participants: Pierrick Gaudry, Quentin Yang.

In a first work 18, we explore the possibility of revealing only the result of an election, without decrypting the individual ballots, or any side-information. The result must be computed in a way such that everyone can verify that it indeed corresponds to the (public) ballot box. Also, even the trust parties who possess the shares of the decryption key should not learn anything more than the winner of the election.

We propose a multi-party computation toolbox dedicated to this kind of problems, and show that it allows us to tackle all well-known tally functions, including the most complicated, like the Condorcet-Schulze, D'Hondt, STV, or Majority Judgement. We also explain how the classical ElGamal encryption (typically based on elliptic curves) can be used, instead of the Paillier scheme that is often chosen in theoretical papers, but is far less frequent in standard crypto libraries.

In 27, we show that the JCJ e-voting protocol that is the basis of many coercion-resistant systems is flawed, in the sense that the tally phase leaks more information than what it should. In some specific scenarios, this can give an advantage to a coercer. We therefore propose a new version of JCJ, that we call CHide, and that relies on the multi-party toolbox that we designed in the previous article. We also refine the existing formal definitions of coercion-resistance, in order to highlight the flaw, and prove that CHide fixes the problem.

7.5.3 Features and usage of Belenios in 2022

Participants: Pierrick Gaudry, Stéphane Glondu.

This short paper 17 was written with V. Cortier and describes the list of features that have been added to the Belenios software in the past few years.

7.5.4 Themis: an on-site voting system with systematic cast-as-intended verification and partial accountability

Participants: Pierrick Gaudry.

In collaboration with members of the PESTO team and members of the Idemia company, we proposed a new voting system. The goal is to offer better guarantees in a context of on-site voting. The main advantages of our system is that it offers the cast-as-intended property, i.e. the machines used by the voters can not cheat when preparing the electronic ballot. This comes with a thorough study of accountability, that is the possibility to blame the right entity, when a problem is detected. Formal proofs of security are provided, using the ProVerif tool.

8.1.1 Consulting with Swiss Post

Participants: Pierrick Gaudry.

Together with the PESTO team, we had a consulting contract with Swiss Post. The topic was e-voting in general, and more precisely various topics (short-term and long-term design evolution, security analysis) related to their solution.

8.1.2 Verifiability during the French legislative elections

Participants: Pierrick Gaudry, Stéphane Glondu.

Together with the PESTO team, we had a contract with the French Ministry of Foreign Affairs (MEAE), in the context of the legislative elections, for which the French citizens from abroad had the possibility to vote over Internet. We played the role of external third-party, as required by the CNIL recommendations for such high-stake elections. While the contract was signed with the MEAE, it also involved interactions with the vendor of the solution (Voxaly), and the ANSSI who was the security advisor for the MEAE.

9.1.1 Sabbatical programme

9.1.2 Research stays abroad

9.2.1 PEPR Quantique, project PQ-TLS

Participants: Xavier Bonnetain, Pierre-Jean Spaenlehauer.

• Program: PEPR Quantique
• Project acronym: PQ-TLS
• Duration: 01/2022 - 12/2026
• Coordinator: Université de Rennes 1
• Other partners: Université de Limoges, Université de Rouen, Université de Bordeaux, Université de Saint-Quentin-en Yvelines, Université de Saint-Étienne, ENS de Lyon, Inria (GRACE, CARAMBA, COSMIQ, PROSECCO), CEA (Grenoble LETI), CNRS Labstic (Lorient).

Since 1996 and the discovery of Shor's algorithm, new quantum threats emerged against classical security protocols and cryptographic primitives. The objective of the PQ-TLS project is to design a quantum-safe version of the security layer of web protocols, via the integration of post-quantum cryptographic primitives and the quantum cryptanalysis of existing systems. The project also aims at developping new techniques to compare existing primitives from the quantum viewpoint and at promoting arising solutions from the academic and industrial research. The goal is to develop a large toolbox whose targets range from the mathematical foundations of post-quantum cryptography to its concrete implementations.

Xavier Bonnetain is the national coordinator of the work package 5 "Quantum cryptanalysis".

Pierre-Jean Spaenlehauer is the local scientific coordinator for the CARAMBA team.

9.2.2 Projet ANR KLEPTOMANIAC

Participants: Pierrick Gaudry, Cécile Pierrot, Pierre-Jean Spaenlehauer, Emmanuel Thomé, Paul Zimmermann.

• Program: ANR AAPG
• Project acronym: KLEPTOMANIAC
• Duration: 01/2022 - 12/2025
• Coordinator: Inria Nancy
• Other partners: ANSSI, LIP6

The RSA cryptosystem and the Diffie-Hellman key exchange protocol in finite fields were the first invented primitives of public-key cryptography.

It is hard to estimate the time and resources that are needed to factor an integer, and thereby how hard it is to break RSA. All regulatory bodies recommend that people either avoid RSA, or prefer large RSA key sizes for safety, above 2048 bits at least. In environments where computing power is plentiful, this recommendation is most often followed. Yet, it is a fact that we do rely on cryptography that uses smaller key sizes.

We plan to employ our expertise to provide solid hardness assessments for key sizes that are relevant today, and for which accuracy in the prediction is important. Our targets for accurate assessment are RSA-1024 and DH-1024 as well as specific discrete logarithm-related problems that arise in the blockchain context. We also intend to develop simulation software that would enable more accurate estimates.

In 2022, the work on the “double matrix” subtask was initiated, in collaboration with Charles Bouillaguet (Sorbonne University). This work is integrated in a branch of Cado-NFS.

9.2.3 ANR Decrypt

Participants: Marine Minier, Virginie Lallemand.

• Program: ANR
• Project acronym: DECRYPT
• Duration: 01/2019 - 12/2023
• Coordinator: Caramba Team, LORIA
• Other partners: LIRIS (Lyon), LIMOS (Clermont-Ferrand), IRISA (Rennes), TASC (Nantes).

This project aims to propose a declarative language dedicated to cryptanalytic problems in symmetric key cryptography using constraint programming (CP) to simplify the representation of attacks, to improve existing attacks and to build new cryptographic primitives that withstand these attacks. We also want to compare the different tools that can be used to solve these problems: SAT and MILP where the constraints are homogeneous and CP where the heterogeneous constraints can allow a more complex treatment.

One of the challenges of this project will be to define global constraints dedicated to the case of symmetric cryptography.

Concerning constraint programming, this project will define new dedicated global constraints, will improve the underlying filtering and solution search algorithms, and will propose dedicated explanations generated automatically. See the web site for more information.

9.3.1 Impact Project LUE DigiTrust

Participants: Marine Minier.

• Program: LUE
• Project acronym: DigiTrust
• Duration: 04/2019 - 12/2022
• Scientific Leader: Marine Minier

The Citizen Trust in the Digital World (acronym DigiTrust) project is part of the latest wave of IMPACT projects within the Lorraine University of Excellence (LUE) initiative proposed under the PIA2 IDEX/I call for tenders -SITE. It was launched in April 2019 and its ambition is to build citizens' trust in the digital world around four areas of research.

The digital revolution has a fundamental impact on daily life, particularly on the way citizens get information, communicate and organize themselves. This revolution also changed the manufacturing and supply of goods and energy, the design of cities, transportation infrastructure, and even administration and politics. New paradigms such as smart cities, manufacturing or the use of connected objects (IoT) rely on permanently connected communication at all scales, which further increases the dependence of modern society on digital technologies. See the web site for more information.

10.1.1 Scientific events: organisation

• Haetham Al Aswad and Ana Rodriguez Cordero created the Ph.D. seminar at Loria, Nancy, which is a monthly seminar held and done by Ph.D. students for PhD students.
• Pierre-Jean Spaenlehauer is a member of the organization committee of the Journées Nationales du Calcul Formel 2022 and 2023.
• Virginie Lallemand co-organized Cyber in Nancy, the summer school in Cybersecurity of the “GDR Sécurité Informatique“.

10.1.2 Scientific events: selection

10.1.3 Journal

10.1.4 Invited talks

• Antoine Leudière was invited to give a talk on Drinfeld modules in cryptography at the INRIA GRACE team seminar, Saclay, France, in May.
• Antoine Leudière was invited to give a talk on the algorithmics of Drinfeld modules at the INRIA LFANT team seminar, Bordeaux, France, in June.
• Antoine Leudière was invited to give a talk on Drinfeld modules in cryptography at the Géométrie et algèbre effectives team seminar, Rennes, France, in September.
• Cécile Pierrot was an invited speaker at the conference Application of Computer Algebra (ACA 2022), August 2022, Istanbul, Turkey.
• Marine Minier was invited to give a talk at “Journées du GDR sécurité” 2022, Paris, France, in June.
• Marine Minier was invited to give a talk at the CISPA/LORIA seminar 2022, Saarbrücken, Germany, in November.
• Xavier Bonnetain was invited to give a talk at the CISPA/LORIA seminar 2022, Saarbrücken, Germany, in October.
• Xavier Bonnetain was invited to give a talk during the FRISIACRYPT 2022 invitation-only seminar.
• Xavier Bonnetain was invited to give a talk for the “Journée de la Sécurité Informatique en Normandie” in Rouen.
• Paul Zimmermann was invited to give a talk on the IEEE 754 standard to the French “Groupe Calcul”, in February (virtual talk).
• Paul Zimmermann was invited to give a talk on CORE-MATH to the FPBench Community Meeting, in March (virtual talk).
• Paul Zimmermann was invited to give a talk on CORE-MATH at the RAIM 2022 (13èmes Rencontres Arithmétique de l'Informatique Mathématique), in November.
• Emmanuel Thomé was invited to give a talk at the Cryptography seminar in Rennes.

10.1.5 Leadership within the scientific community

• Cécile Pierrot is a member of the steering committee of the French working group Code and Cryptography.
• Pierrick Gaudry is a member of the Conseil Scientifique of GdR IM.
• Marine Minier is co-supervisor with Antoine Joux of the virtual cybersecurity center between CISPA and LORIA (2020-2023).

10.1.6 Scientific expertise

• Pierrick Gaudry was a member of a jury for the Innoviris LAUNCH program, whose goal is to fund start-ups created on the basis of academic work.

10.1.7 Research administration

• Pierrick Gaudry is a member of the steering committee of the LHS – Laboratoire Haute Sécurité of LORIA.
• Pierrick Gaudry was a member of the hiring committee for a Professor in computer science and mathematics (26/27) at Ensimag, Grenoble.
• Marine Minier is a member of the steering committee of the LHS – Laboratoire Haute Sécurité of LORIA.
• Marine Minier was a member of the hiring committee for an assistant professor in computer science and mathematics (26/27) at University of Grenoble-Alpes.
• Marine Minier was a member of the hiring committee for a Professor in computer science (27) at University of Nancy.
• Marine Minier was president of the hiring committee for a Professor in computer science (27) at University of Nancy, Télécom.
• Marine Minier was a member of the hiring committee for an assistant professor in computer science (27) for an exchange of positions between University of Nancy and University of Nice.
• Cécile Pierrot was a member of the hiring committee for research scientists “Chargé de Recherche” at Inria Nancy, May 2022.
• Pierre-Jean Spaenlehauer is a member of the Commission des Développements Technologiques of the Inria Nancy – Grand Est research center.
• Paul Zimmermann is member of the scientific committee of the EXPLOR computing center (Université de Lorraine).
• Cécile Pierrot created and leads the working group Intégration Locale at Loria/Inria Nancy. She created the English Coffee Time too, dedicated for all the non-French speakers in the lab.
• Cécile Pierrot is a member of Bureau du Comité des Projets, Inria Nancy.
• Cécile Pierrot is a member of Comité de Centre of Inria Nancy.
• Cécile Pierrot is a member of the working group about remote working at Inria.

10.2.1 Teaching

Marine Minier obtains this year an half Inria Delegation.

• Bachelor
  • Sébastien Duval, Algorithmique et Programmation 2, 38h eq. TD, L1 Informatique, Université de Lorraine, Faculté des sciences et technologies, Vandœuvre-lès-Nancy, France.
  • Sébastien Duval, Algorithmique et Programmation 3, 26h eq. TD, L2 Informatique, Université de Lorraine, Faculté des sciences et technologies, Vandœuvre-lès-Nancy, France.
  • Sébastien Duval, Mathématiques Discrètes 2, 16h eq. TD, L2 Informatique, Université de Lorraine, Faculté des sciences et technologies, Vandœuvre-lès-Nancy, France.
  • Sébastien Duval, Introduction à la sécurité et à la cryptographie, 20h eq. TD, L3 Informatique, Université de Lorraine, Faculté des sciences et technologies, Vandœuvre-lès-Nancy, France.
  • Aurore Guillevic, Intégration Web (R112) and Suivi de projet (SAE-105), 64h eq. TD, IUT 1A, Université de Lorraine, IUT Charlemagne, Nancy, France.
  • Marine Minier, Introduction à la sécurité et à la cryptographie, 35h eq. TD, L3, Université de Lorraine, Faculté des sciences et technologies, Vandœuvre-lès-Nancy, France.
  • Emmanuel Thomé, Introduction to Modern Cryptography, 25h, University of California San Diego, USA.
  • Quentin Yang, Algorithmique et Programmation 3, 28h eq. TD, L2 Informatique, Université de Lorraine, Faculté des sciences et technologies, Vandœuvre-lès-Nancy, France.
• Master
  • Sébastien Duval, Analyse et Conception de Logiciels, 16h eq. TD, M1 Informatique, Université de Lorraine, Faculté des sciences et technologies, Vandœuvre-lès-Nancy, France.
  • Sébastien Duval, Introduction à la cryptographie, 12h eq. TD, M1 Informatique, Université de Lorraine, Faculté des sciences et technologies, Vandœuvre-lès-Nancy, France.
  • Sébastien Duval, Sécurité des Systèmes d'Information, 35h eq. TD, M2 Informatique, Université de Lorraine, Faculté des sciences et technologies, Vandœuvre-lès-Nancy, France.
  • Sébastien Duval, Sécurité des Applications Web, 32h eq. TD, M2 Informatique, Université de Lorraine, Faculté des sciences et technologies, Vandœuvre-lès-Nancy, France.
  • Aurore Guillevic, Elliptic Curves - Number Theory and Cryptography, 72h eq. TD, Master Mathématiques et Master Informatique, Aarhus University, Aarhus, Danemark.
  • Pierre-Jean Spaenlehauer, Théorie analytique des nombres, géométrie algébrique, et applications à la cryptographie, 24h eq. TD, M2 Mathématiques Fondamentales et Appliquées, Université de Lorraine, Faculté des sciences et technologies, Vandœuvre-lès-Nancy, France.
  • Marine Minier, Contrôle d'accès, 40h eq. TD, M2 Informatique, Université de Lorraine, Faculté des sciences et technologies, Vandœuvre-lès-Nancy, France.
  • Marine Minier, Intégration Méthodologique, 36h eq. TD, M2 Informatique, Université de Lorraine, Faculté des sciences et technologies, Vandœuvre-lès-Nancy, France.
  • Marine Minier Sécurité Informatique, 18h eq. TD, M2 droit, Université de Lorraine.
  • Marine Minier is head of the M2 SIRAV, Université de Lorraine, Faculté des sciences et technologies, Vandœuvre-lès-Nancy, France.
  • Emmanuel Thomé, The Number Field Sieve (CSE 291-14, graduate course), 25h, University of California San Diego, USA.
• Engineering school
  • Cécile Pierrot, Introduction to Cryptography, 54h eq. TD, Mastère spécialisé de cybersécurité, École des Mines de Nancy, France.
  • Haetham AL ASWAD, Programming languages, 22h eq. TD, Second year of Engineering, École des Mines de Nancy, France.
  • Antoine Leudière, Programming and Data Structures: Python, 22h eq. TD, First year of Engineering, École des Mines de Nancy, France.
  • Antoine Leudière, Algorithms and complexity, 22h eq. TD, First year of Engineering, École des Mines de Nancy, France.
  • Antoine Leudière, Database essentials, 18h eq. TD, Second year of Engineering, École des Mines de Nancy, France.
  • Ana Margarita Rodríguez Cordero, Programming and Data Structures: Python, 22h eq. TD, First year of Engineering, École des Mines de Nancy, France.

10.2.2 Supervision

• Ph.D. in progress: Hamid Boukerrou, Synthèse de nouveaux automates à états finis décrits par une représentation matricielle: application à la cryptographie, since Oct. 2019, Marine Minier and Gilles Millerioux. Defence is planed for the 4th of April 2023.
• Ph.D. in progress: Haetham Al Aswad, Number field sieve for discrete logarithm, since Oct. 2021, Cécile Pierrot and Emmanuel Thomé.
• Ph.D. completed: Youssef El Housni, The Arithmetic of Pairing-Based Proof Systems, November 2019–November 2022, co-advised by François Morain and Daniel Augot (HDR, GRACE team, doctoral school ED-IPP), and Aurore Guillevic.
• Ph.D. in progress: Antoine Leudière, Isogenies of Drinfeld modules and post-quantum cryptography, since Oct. 2021, Pierre-Jean Spaenlehauer and Emmanuel Thomé.
• Ph.D. in progress: Ana Rodriguez Cordero, Design and Cryptanalysis of New Symmetric Key Cryptographic Primitives, since Oct. 2021, Virginie Lallemand and Marine Minier.
• Ph.D. in progress: Quentin Yang, Design and analysis of e-voting protocols, since Oct. 2020, Pierrick Gaudry and Véronique Cortier (PESTO team).

10.2.3 Juries

• Pierrick Gaudry was reviewer of the PhD thesis Efficient protocols for testing proximity to algebraic codes defended by Sarah Bordage, June 2022, École polytechnique.
• Aurore Guillevic was member of the PhD defense committee of Youssef El Housni, The Arithmetic of Pairing-Based Proof Systems, defended on November 18, 2022, at École Polytechnique, Palaiseau.
• Cécile Pierrot was a jury member during the PhD defense of Andy Russon, January 2022, Rennes.
• Marine Minier was a reviewer and the president of the jury of the PhD defense of Tanguy Gernot, November 2022, Caen.
• Marine Minier was a reviewer of the PhD defense of Paul Frixons, November 2022, Paris.
• Marine Minier was president of the jury of the PhD defense of Mohamed Traoré, May 2022, Grenoble-Alpes.
• Marine Minier was president of the jury of the PhD defense of Bizhan Alipour, March 2022, Nancy.
• Marine Minier was member of the jury of the HDR defense of Marc Pouget, June 2022, Nancy.
• Marine Minier was member of the jury of the HDR defense of Charles Bouillaguet, March 2022, Paris.
• Marine Minier was member of the jury of the PhD defense of Loïc Rouquette, November 2022, Lyon.
• Marine Minier was member of the jury of the PhD defense of Victor Mollimard, January 2022, Rennes.
• Pierre-Jean Spaenlehauer was a jury member for the PhD defense of Maxime Bros, December 2022, Limoges.
• Emmanuel Thomé was a jury member for the PhD defense of Olivier Bernard, June 2022, Rennes.

10.3.1 Internal or external Inria responsibilities

• Marine Minier is assistant director of the LORIA laboratory (450 persons) since September 2021.
• Marine Minier is responsible of the axis CyberSecurity for the LORIA Lab.

10.3.2 Articles and contents

• Cécile Pierrot and Marine Minier made a few-minutes video about women in science, with the help of the Loria laboratory.

10.3.3 Education

• Cécile Pierrot, Pierre-Jean Spaenlehauer and Paul Zimmermann participated in the Math-En-Jeans project. They supervised a group of teenagers from the Lycée Français Vauban du Luxembourg.
• Cécile Pierrot gave a talk for the association Science Ouverte dedicated to high school students from disadvantaged backgrounds. April 2022, Sorbonne Université, Paris.
• Aurore Guillevic participated in the 1 scientifique 1 classe chiche program and presented her work as researcher in computer science to 1st year high school teenagers at Verdun and Longwy.
• Quentin Yang participated in La fête de la science, where he held a workshop to present the security of electronic protocols, together with Elise Klein and Maïwenn Racouchot (PESTO team).
• Sébastien Duval participates to the organisation of Cyber Humanum Est, a 3-day-long exercise simulating a cyber war, for students of multiple origins (specialised bachelor, masters 1 and 2, engineering schools in computer science, and masters 1 and 2 in social sciences).

10.3.4 Interventions

• Pierre-Jean Spaenlehauer and Paul Zimmermann are involved in the animation of a MATh. en. JEANS activity at the Lycée Vauban, Luxembourg.
• In November, Paul Zimmermann initiated to cryptography two classes of “troisième” of a “collège” at Is-sur-Tille, and helped a few selected students to (re)decrypt the letter from Charles Quint.

International journals

• 10 articleD. F.Diego F. Aranha, Y.Youssef El Housni and A.Aurore Guillevic. A survey of elliptic curves for proof systems.Designs, Codes and CryptographyDecember 2022, 46
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• 11 articleS.Soline Blanc, A.Abdelkader Lahmadi, K.Kévin Le Gouguec, M.Marine Minier and L.Lama Sleem. Benchmarking of lightweight cryptographic algorithms for wireless IoT networks.Wireless Networks288November 2022, 3453-3476
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• 12 articleJ.Julien Francq, L.Loic Besson, P.Paul Huynh, P.Philippe Guillot, G.Gilles Millérioux and M.Marine Minier. Non-triangular self-synchronizing stream ciphers.IEEE Transactions on Computers711January 2022, 134-145
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• 13 articleA.Antoine Joux and C.Cécile Pierrot. Algorithmic aspects of elliptic bases in finite field discrete logarithm algorithms.Advances in Mathematics of Communications2022
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• 14 articleV.Virginie Lallemand, M.Marine Minier and L.Loïc Rouquette. Automatic Search of Rectangle Attacks on Feistel Ciphers: Application to WARP.IACR Transactions on Symmetric Cryptology20222June 2022, 113-140
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International peer-reviewed conferences

• 15 inproceedingsX.Xavier Bonnetain, A.André Schrottenloher and F.Ferdinand Sibleyras. Beyond quadratic speedups in quantum attacks on symmetric schemes.Lecture Notes in Computer ScienceEUROCRYPT 2022 - 41st Annual International Conference on the Theory and Applications of Cryptographic TechniquesLNCS-13277Advances in Cryptology – EUROCRYPT 2022Part IIITrondheim, NorwaySpringer International PublishingMay 2022, 315-344
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• 16 inproceedingsM.Mikaël Bougon, H.Hervé Chabanne, V.Véronique Cortier, A.Alexandre Debant, E.Emmanuelle Dottax, J.Jannik Dreier, P.Pierrick Gaudry and M.Mathieu Turuani. Themis: an On-Site Voting System with Systematic Cast-as-intended Verification and Partial Accountability.CCS 2022 - The ACM Conference on Computer and Communications SecurityLos Angeles, United StatesACM2022
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• 17 inproceedingsV.Véronique Cortier, P.Pierrick Gaudry and S.Stéphane Glondu. Features and usage of Belenios in 2022.The International Conference for Electronic Voting (E-Vote-ID 2022)Bregenz / Hybrid, AustriaOctober 2022
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• 18 inproceedingsV.Véronique Cortier, P.Pierrick Gaudry and Q.Quentin Yang. A toolbox for verifiable tally-hiding e-voting systems.ESORICS 2022 - 27th European Symposium on Research in Computer SecurityCopenhague, DenmarkSeptember 2022
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• 19 inproceedingsY.Youssef El Housni and A.Aurore Guillevic. Families of SNARK-friendly 2-chains of elliptic curves.LNCSAdvances in Cryptology - EUROCRYPT 2022 - 41st Annual International Conference on the Theory and Applications of Cryptographic Techniques13276EUROCRYPT 2022Trondheim / Hybrid, NorwaySpringerMay 2022, 367-396
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• 20 inproceedingsY.Youssef El Housni, A.Aurore Guillevic and T.Thomas Piellard. Co-factor clearing and subgroup membership testing on pairing-friendly curves.AFRICACRYPT 2022 - 13th International Conference on Cryptology13503LNCSFes, MoroccoSpringerOctober 2022, 518--536
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• 21 inproceedingsL.Loïc Rouquette, D.David Gerault, M.Marine Minier and C.Christine Solnon. And Rijndael? Automatic Related-key Differential Analysis of Rijndael.Progress in Cryptology - AFRICACRYPT 2022, 13th International Conference on Cryptology in Africa, Fes, Morocco, July 18–20, 2022 ProceedingsAfricaCrypt 2022 - 13th International Conference on Cryptology AfricaCryptLNCS-13503LNCSFes, MoroccoSpringer2022, 150-175
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• 22 inproceedingsA.Alexei Sibidanov, P.Paul Zimmermann and S.Stéphane Glondu. The CORE-MATH Project.ARITH 2022 - 29th IEEE Symposium on Computer Arithmeticvirtual, FranceSeptember 2022
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• 23 inproceedingsS.Samuel Vivien. Parallel integer multiplication.30th Euromicro International Conference on Parallel, Distributed andNetwork-based Processing (PDP 2022)PDP 2022 - 30th Euromicron International Conference on Parallel, Distributed, and Network-Based ProcessingValladoid, Spain2022
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Conferences without proceedings

• 24 inproceedingsH.Hamid Boukerrou, G.Gilles Millérioux and M.Marine Minier. Towards a new design of ciphers to secure CPS: the role of control theory.26th International Conference on System Theory, Control and Computing, ICSTCC 2022Sinaia, RomaniaOctober 2022
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• 25 inproceedingsV.Véronique Cortier, A.Alexandre Debant and P.Pierrick Gaudry. A privacy attack on the Swiss Post e-voting system.RWC 2022 - Real World Crypto SymposiumAmsterdam (NETHERLANDS), NetherlandsNovember 2021
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Reports & preprints

• 26 miscH.Haetham Al Aswad and C.Cécile Pierrot. Individual Discrete Logarithm with Sublattice Reduction.July 2022
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• 27 misc V.Véronique Cortier, P.Pierrick Gaudry and Q.Quentin Yang. Is the JCJ voting system really coercion-resistant? April 2022
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• 28 miscV.Vincenzo Innocente and P.Paul Zimmermann. Accuracy of Mathematical Functions in Single, Double, Extended Double and Quadruple Precision.September 2022
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• 29 miscP.-J.Pierre-Jean Spaenlehauer and A.Antoine Leudière. Computing a Group Action from the Class Field Theory of Imaginary Hyperelliptic Function Fields.April 2022
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• 30 reportL.Lauriane Turelier. Extension of the SLZ algorithm to bivariate functions.INRIA NancyJuly 2022
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• 31 miscP.Paul Zimmermann. Note on FastTwoSum with Directed Roundings.October 2022
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Other scientific publications

• 32 articleF.Fabrice Boudot, P.Pierrick Gaudry, A.Aurore Guillevic, N.Nadia Heninger, E.Emmanuel Thomé and P.Paul Zimmermann. The State of the Art in Integer Factoring and Breaking Public-Key Cryptography.IEEE Security and Privacy Magazine202March 2022, 80-86
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Scientific popularization

• 33 bookV.Véronique Cortier and P.Pierrick Gaudry. Le vote électronique - les défis du secret et de la transparence.Odile JacobMay 2022
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Softwares

• 34 softwareG.Guillaume Hanrot, P.Paul Zimmermann, V.Vincent Lefèvre, P.Patrick Pélissier and P.Philippe Théveny. GNU MPFR.4.2.0January 2023GNU General Public License
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