SANGRIA

Research project funded by the french Agence Nationale de la Recherche (2021-2026). ANR-21-CE39-0006

Partners

• École normale supérieure / DI-ENS
• École polytechnique / LIX
• Sorbonne Université / LIP6 and IMJ
• Télécom Paris / LTCI
• Université de Bordeaux / IMB
• Université Grenoble Alpes / LJK
• Université de Montpellier / LIRMM

• Beginning and duration of the scientific project: October 2021 - 60 Months
• Project coordinator: Damien Vergnaud

Project Summary

Cryptology is a crucial and ubiquitous component of cybersecurity. The development of information technology has brought great convenience to our lives but require cryptographic methods that go far beyond basic secure communication (i.e. confidentiality, integrity or authentication). The amount of sensitive data stored in digital form has grown tremendously and we now store and process them daily on nomad devices as well as in the cloud. This comes with many novel attack surfaces. Managing and protecting personal, financial or medical data is challenging and seems impossible for users with current tools.

Secure distributed computation has long stood in the realm of theoretical cryptography but it was known to have the potential to provide a disruptive change for practical security solutions. The concept was introduced by Yao in the 1980s and it allows mutually distrusting parties to run joint computations without disclosing any participant’s private inputs. New cryptographic tools have been invented in recent years (e.g. fully-homomorphic encryption, functional encryption, succinct proof systems...). These constructions have opened the door to applications that were previously believed unattainable in practice (e.g. Cloud Computing, Big Data, Blockchain or the Internet of Things). There is currently a strong interest in secure distributed computation from governments and security organisations (in particular the National Institute of Standards and Technology (NIST)), military, academia and industry. We are close to the stage where the secure distributed computation protocols can be applied to real-world security issues. We now list the main scientific challenges in the project.

The main scientific challenges are (1) to construct specific protocols that take into account practical constraints and prove them secure, (2) to implement them and to improve the efficiency of existing protocols significantly. The SANGRIA project (for Secure distributed computAtioN: cryptoGRaphy, combinatorIcs and computer Algebra) aims to undertake research in these two aspects while combining research from cryptography, combinatorics and computer algebra. It is expected to impact central problems in secure distributed computation, while enriching the general landscape of cryptography.

Publications

2024

1. Secure Multi-Party Linear Algebra with Perfect Correctness
   Jules Maire, and Damien Vergnaud
   IACR Comm. in Cryptology. 1 (to appear), 1, (2024).

2023

1. Commitments with Efficient Zero-Knowledge Arguments from Subset Sum Problems
   Jules Maire, and Damien Vergnaud
   In Computer Security - ESORICS 2023 - 28th European Symposium on Research in Computer Security, The Hague, The Netherlands, September 25-29, 2023, Proceedings, Part I (Gene Tsudik, Mauro Conti, Kaitai Liang, and Georgios Smaragdakis, eds), Springer, Lecture Notes in Computer Science, vol. 14344, pp. 189–208 (2023).
   open access doi
2. Efficient Zero-Knowledge Arguments and Digital Signatures via Sharing Conversion in the Head
   Jules Maire, and Damien Vergnaud
   In Computer Security - ESORICS 2023 - 28th European Symposium on Research in Computer Security, The Hague, The Netherlands, September 25-29, 2023, Proceedings, Part I (Gene Tsudik, Mauro Conti, Kaitai Liang, and Georgios Smaragdakis, eds), Springer, Lecture Notes in Computer Science, vol. 14344, pp. 435–454 (2023).
   doi
3. I want to ride my BICYCL: BICYCL Implements CryptographY in CLass groups
   Cyril Bouvier, Guilhem Castagnos, Laurent Imbert, and Fabien Laguillaumie
   J. Cryptol. to appear, (2023).
   open access
4. Pattern Matching in Encrypted Stream from Inner Product Encryption
   Elie Bouscatié, Guilhem Castagnos, and Olivier Sanders
   In Public-Key Cryptography - PKC 2023 - 26th IACR International Conference on Practice and Theory of Public-Key Cryptography, Atlanta, GA, USA, May 7-10, 2023, Proceedings, Part I (Alexandra Boldyreva, and Vladimir Kolesnikov, eds), Springer, Lecture Notes in Computer Science, vol. 13940, pp. 774–801 (2023).
   open access doi
5. Bandwidth-efficient threshold EC-DSA revisited: Online/offline extensions, identifiable aborts proactive and adaptive security
   Guilhem Castagnos, Dario Catalano, Fabien Laguillaumie, Federico Savasta, and Ida Tucker
   Theor. Comput. Sci. 939, pp. 78-104 (2023).
   doi

2022

1. Zero-Knowledge Protocols for the Subset Sum Problem from MPC-in-the-Head with Rejection
   Thibauld Feneuil, Jules Maire, Matthieu Rivain, and Damien Vergnaud
   In Advances in Cryptology - ASIACRYPT 2022 - 28th International Conference on the Theory and Application of Cryptology and Information Security, Taipei, Taiwan, December 5-9, 2022, Proceedings (Shweta Agrawal, and Dongdai Lin, eds), Springer, Lecture Notes in Computer Science, vol. to appear, (2022).
   open access
2. Threshold Linearly Homomorphic Encryption on Z/2^kZ
   Guilhem Castagnos, Fabien Laguillaumie, and Ida Tucker
   In Advances in Cryptology - ASIACRYPT 2022 - 28th International Conference on the Theory and Application of Cryptology and Information Security, Taipei, Taiwan, December 5-9, 2022, Proceedings (Shweta Agrawal, and Dongdai Lin, eds), Springer, Lecture Notes in Computer Science, vol. to appear, (2022).
   open access
3. A tighter proof for CCA secure inner product functional encryption: Genericity meets efficiency
   Guilhem Castagnos, Fabien Laguillaumie, and Ida Tucker
   Theor. Comput. Sci. 914, pp. 84-113 (2022).
   doi