Paper 2011/335

New look at impossibility result on Dolev-Yao models with hashes

István Vajda

Abstract

Backes, Pfitzmann and Waidner showed in [7] that for protocols with hashes Dolev-Yao style models do not have cryptographically sound realization in the sense of BRSIM/UC in the standard model of cryptography. They proved that random oracle model provides a cryptographically sound realization. Canetti [9] introduced the notion of oracle hashing “towards realizing random oracles”. Based on these two approaches, we propose a random hash primitive, which already makes possible cryptographically sound realization in the sense of BRSIM/UC in the standard model of cryptography.