Abstract

We introduce the notion of non-malleable noninteractive zero-knowledge (NIZK) proof systems. We show how to transform any ordinary NIZK proof system into one that has strong non-malleability properties. We then show that the elegant encryption scheme of Naor and Yung [NY] can be made secure against the strongest form of chosen-ciphertext attack by using a non-malleable NIZK proof instead of a standard NIZK proof. Our encryption scheme is simple to describe and works in the standard cryptographic model under general assumptions. The encryption scheme can be realized assuming the existence of trapdoor permutations. 1 Introduction Modern cryptography provides us with several fundamental tools, from encryption schemes to zeroknowledge proofs. For each of these tools, we have some intuition about what they "should" achieve. But we must be careful to understand the gap between our intuition and what we can actually achieve. Indeed, a major goal of cryptography is to refine our tools to br...

Citations

1130	Random oracles are practical: A paradigm for designing efficient protocols - Bellare, Rogaway - 1993
388	Relations Among Notions of Security for Public-Key Encryption Schemes - Bellare, Desai, et al. - 1998
193	A modular approach to the design and analysis of authentication and key exchange protocols (extended abstract - Bellare, Canetti, et al. - 1998
176	Optimal asymmetric encryption – how to encrypt with RSA - Bellare, Rogaway - 1994
34	New paradigms for digital signatures and message authentication based on non-interative zero knowledge proofs - Bellare, Goldwasser - 1990