Paper 2023/1744
Don't Eject the Impostor: Fast Three-Party Computation With a Known Cheater (Full Version)
Abstract
Secure multi-party computation (MPC) enables (joint) computations on sensitive data while maintaining privacy. In real-world scenarios, asymmetric trust assumptions are often most realistic, where one somewhat trustworthy entity interacts with smaller clients. We generalize previous two-party computation (2PC) protocols like MUSE (USENIX Security'21) and SIMC (USENIX Security'22) to the three-party setting (3PC) with one malicious party, avoiding the performance limitations of dishonest-majority inherent to 2PC. We introduce two protocols, Auxiliator and Socium, in a machine learning (ML) friendly design with a fast online phase and novel verification techniques in the setup phase. These protocols bridge the gap between prior 3PC approaches that considered either fully semi-honest or malicious settings. Auxiliator enhances the semi-honest two-party setting with a malicious helper, significantly improving communication by at least two orders of magnitude. Socium extends the client-malicious setting with one malicious client and a semi-honest server, achieving substantial communication improvement by at least one order of magnitude compared to SIMC. Besides an implementation of our new protocols, we provide the first open-source implementation of the semi-honest 3PC protocol ASTRA (CCSW'19) and a variant of the malicious 3PC protocol SWIFT (USENIX Security'21).
Note: This is the full version of our research paper that has been accepted for publication at the 2024 IEEE Security & Privacy (IEEE S&P) conference.
Metadata
- Available format(s)
- Category
- Cryptographic protocols
- Publication info
- Published elsewhere. Major revision. IEEE Security & Privacy (IEEE S&P) 2024
- Keywords
- multi-party computationMPC3PCclient-malicious settingasymmetric trustprivacy-preserving machine learningPPML
- Contact author(s)
-
brueggemann @ encrypto cs tu-darmstadt de
oliver schick @ protonmail com
schneider @ encrypto cs tu-darmstadt de
ajith suresh @ tii ae
yalame @ encrypto cs tu-darmstadt de - History
- 2023-11-13: approved
- 2023-11-11: received
- See all versions
- Short URL
- https://ia.cr/2023/1744
- License
-
CC BY-SA
BibTeX
@misc{cryptoeprint:2023/1744, author = {Andreas Brüggemann and Oliver Schick and Thomas Schneider and Ajith Suresh and Hossein Yalame}, title = {Don't Eject the Impostor: Fast Three-Party Computation With a Known Cheater (Full Version)}, howpublished = {Cryptology {ePrint} Archive, Paper 2023/1744}, year = {2023}, url = {https://eprint.iacr.org/2023/1744} }