Cryptology ePrint Archive: Report 2015/246

Implicit Zero-Knowledge Arguments and Applications to the Malicious Setting

Fabrice Benhamouda and Geoffroy Couteau and David Pointcheval and Hoeteck Wee

Abstract: We introduce \emph{implicit zero-knowledge} arguments (iZK) and simulation-sound variants thereof (SSiZK); these are lightweight alternatives to zero-knowledge arguments for enforcing semi-honest behavior. Our main technical contribution is a construction of efficient two-flow iZK and SSiZK protocols for a large class of languages under the (plain) DDH assumption in cyclic groups in the common reference string model. As an application of iZK, we improve upon the round-efficiency of existing protocols for securely computing inner product under the DDH assumption. This new protocol in turn provides privacy-preserving biometric authentication with lower latency.

Category / Keywords: cryptographic protocols / hash proof systems, zero-knowledge, malicious adversaries, two-party computation, inner product

Original Publication (with major differences): IACR-CRYPTO-2015

Date: received 16 Mar 2015, last revised 23 Dec 2016

Contact author: fabrice benhamouda at ens fr

Available format(s): PDF | BibTeX Citation

Version: 20161223:164835 (All versions of this report)

Short URL: ia.cr/2015/246