Towards Plaintext-Aware Public-Key Encryption without Random Oracles

Mihir Bellare; Adriana Palacio

Paper 2004/221

Towards Plaintext-Aware Public-Key Encryption without Random Oracles

Mihir Bellare and Adriana Palacio

Abstract

We consider the problem of defining and achieving plaintext-aware encryption without random oracles in the classical public-key model. We provide definitions for a hierarchy of notions of increasing strength: PA0, PA1 and PA2, chosen so that PA1+IND-CPA => IND-CCA1 and PA2+IND-CPA => IND-CCA2. Towards achieving the new notions of plaintext awareness, we show that a scheme due to Damgard, denoted DEG, and the ``lite'' version of the Cramer-Shoup scheme, denoted CSL, are both PA0 under the KEA0 assumption of Damgard, and PA1 under an extension of this assumption called KEA1. As a result, DEG is the most efficient proven IND-CCA1 scheme known.

Metadata

Available format(s): PDF PS
Category: Foundations
Publication info: Published elsewhere. An extended abstract of this paper appears in the proceedings of the Asiacrypt 2004 conference. This is the full version.
Keywords: encryption chosen-ciphertext attacks plaintext awareness
Contact author(s): mihir @ cs ucsd edu
History: 2004-09-02: revised; 2004-09-02: received; See all versions
Short URL: https://ia.cr/2004/221
License: CC BY

BibTeX

@misc{cryptoeprint:2004/221,
      author = {Mihir Bellare and Adriana Palacio},
      title = {Towards Plaintext-Aware Public-Key Encryption without Random Oracles},
      howpublished = {Cryptology {ePrint} Archive, Paper 2004/221},
      year = {2004},
      url = {https://eprint.iacr.org/2004/221}
}