Cryptology ePrint Archive: Report 2021/1230

Two-Round Maliciously Secure Computation with Super-Polynomial Simulation

Amit Agarwal and James Bartusek and Vipul Goyal and Dakshita Khurana and Giulio Malavolta

Abstract: We propose the first maliciously secure multi-party computation (MPC) protocol for general functionalities in two rounds, without any trusted setup. Since polynomial-time simulation is impossible in two rounds, we achieve the relaxed notion of superpolynomial-time simulation security [Pass, EUROCRYPT 2003]. Prior to our work, no such maliciously secure protocols were known even in the two-party setting for functionalities where both parties receive outputs. Our protocol is based on the sub-exponential security of standard assumptions plus a special type of non-interactive non-malleable commitment.

At the heart of our approach is a two-round multi-party conditional disclosure of secrets (MCDS) protocol in the plain model from bilinear maps, which is constructed from techniques introduced in [Benhamouda and Lin, TCC 2020].

Category / Keywords: cryptographic protocols / superpolynomial simulation, secure multi-party computation, conditional disclosure of secrets

Original Publication (with major differences): IACR-TCC-2021

Date: received 17 Sep 2021, last revised 17 Sep 2021

Contact author: amita2 at illinois edu, bartusek james at gmail com, vipul at cmu edu, dakshita at illinois edu, giulio malavolta at hotmail it

Available format(s): PDF | BibTeX Citation

Version: 20210920:105746 (All versions of this report)

Short URL: ia.cr/2021/1230


[ Cryptology ePrint archive ]