Cryptology ePrint Archive: Report 2014/661

One-Round Deniable Key Exchange with Perfect Forward Security

Weiqiang Wen and Libin Wang and Min Xie

Abstract: In response to the need for secure one-round authenticated key exchange protocols providing both perfect forward secrecy and full deniability, we put forward a new paradigm for constructing protocols from a Diffie-Hellman type protocol plus a non-interactive designated verifier proof of knowledge (DV-PoK) scheme. We define the notion of DV-PoK which is a variant of non-interactive zero-knowledge proof of knowledge, and provide an efficient DV-PoK scheme as a central technical building block of our protocol. The DV-PoK scheme possesses nice properties such as unforgeability and symmetry which help our protocol to achieve perfect forward secrecy and full deniability respectively. Moreover, the security properties are formally proved in the Canetti-Krawczyk model under the Gap Diffie-Hellman assumption. In sum, our protocol offers a remarkable combination of salient security properties and efficiency, and the notion of DV-PoK is of independent interests.

Category / Keywords: cryptographic protocols / Authenticated Key Exchange; Perfect Forward Secrecy; Full Deniability; Non-Interactive Zero-Knowledge; Proof of Knowledge

Date: received 25 Aug 2014

Contact author: lbwang at scnu edu cn

Available format(s): PDF | BibTeX Citation

Version: 20140828:221527 (All versions of this report)

Short URL: ia.cr/2014/661

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