A Compiler of Two-Party Protocols for Composable and Game-Theoretic Security, and Its Application to Oblivious Transfer

Abstract

In this paper, we consider the following question: Does composing protocols having gametheoretic security result in a secure protocol in the sense of game-theoretic security? In order to discuss the composability of game-theoretic properties, we study security of cryptographic protocols in terms of the universal composability (UC) and game theory simultaneously. The contribution of this paper is the following: (i) We propose a compiler of two-party protocols in the local universal composability (LUC) framework such that it transforms any two-party protocol secure against semi-honest adversaries into a protocol secure against malicious adversaries in the LUC framework; (ii) We consider the application of our compiler to oblivious transfer (OT) protocols, by which we obtain a construction of OT meeting both UC security and game-theoreticsecurity.