All languages in NP have divertible zero-knowledge proofs and arguments under cryptographic assumptions

Abstract

We present a divertible zero-knowledge proof (argument) for SAT under the assumption that probabilistic encryption homomorphisms exist. Our protocol uses a simple ‘swapping’ technique which can be applied to many zero knowledge proofs (arguments). In particular we obtain a divertible zero-knowledge proof for graph isomorphism. The consequences for abuse-free zero-knowledge proofs are also considered.