Abstract
Motivated by the goal of designing versatile and flexible secure computation protocols that at the same time require as little interaction as possible, we present new multiparty reusable Non-Interactive Secure Computation (mrNISC) protocols. This notion, recently introduced by Benhamouda and Lin (TCC 2020), is essentially two-round Multi-Party Computation (MPC) protocols where the first round of messages serves as a reusable commitment to the private inputs of participating parties. Using these commitments, any subset of parties can later compute any function of their choice on their respective inputs by just sending a single message to a stateless evaluator, conveying the result of the computation but nothing else. Importantly, the input commitments can be computed without knowing anything about other participating parties (neither their identities nor their number) and they are reusable across any number of desired computations. We give a construction of mrNISC that achieves standard simulation security, as classical multi-round MPC protocols achieve. Our construction relies on the Learning With Errors (LWE) assumption with polynomial modulus, and on the existence of a pseudorandom function (PRF) in NC1. We achieve semi-malicious security in the plain model and malicious security by further relying on trusted setup (which is unavoidable for mrNISC). In comparison, the only previously known constructions of mrNISC were either using bilinear maps or using strong primitives such as program obfuscation. We use our mrNISC to obtain new Multi-Key FHE (MKFHE) schemes with threshold decryption: In the CRS model, we obtain threshold MKFHE for NC 1 based on LWE with only polynomial modulus and PRFs in NC1, whereas all previous constructions rely on LWE with super-polynomial modulus-to-noise ratio.In the plain model, we obtain threshold levelled MKFHE for P based on LsWE with polynomial modulus, PRF in NC 1, and NTRU, and another scheme for constant number of parties from LWE with sub-exponential modulus-to-noise ratio. The only known prior construction of threshold MKFHE (Ananth et al., TCC 2020) in the plain model restricts the set of parties who can compute together at the onset.
| Original language | American English |
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| Title of host publication | Advances in Cryptology – EUROCRYPT 2021 - 40th Annual International Conference on the Theory and Applications of Cryptographic Techniques, Proceedings |
| Editors | Anne Canteaut, François-Xavier Standaert |
| Publisher | Springer Science and Business Media Deutschland GmbH |
| Pages | 724-753 |
| Number of pages | 30 |
| Volume | 12697 |
| ISBN (Print) | 9783030778859 |
| DOIs | |
| State | Published - 2021 |
| Event | 40th Annual International Conference on the Theory and Applications of Cryptographic Techniques, EUROCRYPT 2021 - Zagreb, Croatia Duration: 17 Oct 2021 → 21 Oct 2021 |
Publication series
| Name | Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) |
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| Volume | 12697 LNCS |
| ISSN (Print) | 0302-9743 |
| ISSN (Electronic) | 1611-3349 |
Conference
| Conference | 40th Annual International Conference on the Theory and Applications of Cryptographic Techniques, EUROCRYPT 2021 |
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| Country/Territory | Croatia |
| City | Zagreb |
| Period | 17/10/21 → 21/10/21 |
Bibliographical note
Funding Information:Acknowledgments. Aayush Jain was supported by a Google PhD fellowship in the area of security and privacy (2018) and in part from DARPA SAFEWARE and SIEVE awards, NTT Research, NSF Frontier Award 1413955, and NSF grant 1619348, BSF grant 2012378, a Xerox Faculty Research Award, a Google Faculty Research Award, an equipment grant from Intel, and an Okawa Foundation Research Grant. This material is based upon work supported by the Defense Advanced Research Projects Agency through Award HR00112020024 and the ARL under Contract W911NF-15-C-0205.
Funding Information:
Aayush Jain was supported by a Google PhD fellowship in the area of security and privacy (2018) and in part from DARPA SAFEWARE and SIEVE awards, NTT Research, NSF Frontier Award 1413955, and NSF grant 1619348, BSF grant 2012378, a Xerox Faculty Research Award, a Google Faculty Research Award, an equipment grant from Intel, and an Okawa Foundation Research Grant. This material is based upon work supported by the Defense Advanced Research Projects Agency through Award HR00112020024 and the ARL under Contract W911NF-15-C-0205. Ilan Komargodski is supported in part by an Alon Young Faculty Fellowship and by an ISF grant (No. 1774/20). Huijia Lin was supported by NSF grants CNS-1528178, CNS-1929901, CNS-1936825 (CAREER), CNS-2026774, a Hellman Fellowship, a JP Morgan AI Research Award, a Simons Collaboration grant on the Theory of Algorithmic Fairness, the Defense Advanced Research Projects Agency (DARPA) and Army Research Office (ARO) under Contract No. W911NF-15-C-0236, and a subcontract No. 2017-002 through Galois. The views expressed are those of the authors and do not reflect the official policy or position of the Department of Defense, DARPA, the National Science Foundation, or the U.S. Government.
Funding Information:
Ilan Komargodski is supported in part by an Alon Young Faculty Fellowship and by an ISF grant (No. 1774/20).
Funding Information:
Huijia Lin was supported by NSF grants CNS-1528178, CNS-1929901, CNS-1936825 (CAREER), CNS-2026774, a Hellman Fellowship, a JP Morgan AI Research Award, a Simons Collaboration grant on the Theory of Algorithmic Fairness, the Defense Advanced Research Projects Agency (DARPA) and Army Research Office (ARO) under Contract No. W911NF-15-C-0236, and a subcontract No. 2017-002 through Galois.
Publisher Copyright:
© 2021, International Association for Cryptologic Research.