Paper 2009/189
Efficient Unidirectional Proxy Re-Encryption
Sherman S. M. Chow, Jian Weng, Yanjiang Yang, and Robert H. Deng
Abstract
Proxy re-encryption (PRE) allows a semi-trusted proxy to convert a ciphertext originally intended for Alice into one encrypting the same plaintext for Bob. The proxy only needs a re-encryption key given by Alice, and cannot learn anything about the plaintext encrypted. This adds flexibility in various applications, such as confidential email, digital right management and distributed storage. In this paper, we study unidirectional PRE, which the re-encryption key only enables delegation in one direction but not the opposite. In PKC 2009, Shao and Cao proposed a unidirectional PRE assuming the random oracle. However, we show that it is vulnerable to chosen-ciphertext attack (CCA). We then propose an efficient unidirectional PRE scheme (without resorting to pairings). We gain high efficiency and CCA-security using the ``token-controlled encryption'' technique, under the computational Diffie-Hellman assumption, in the random oracle model and a relaxed but reasonable definition.
Metadata
- Available format(s)
-
PDF
PS
- Category
- Public-key cryptography
- Publication info
- Published elsewhere. This is a preliminary full version of a paper appearing in Africacrypt 2010.
- Keywords
- proxy re-encryptionunidirectionalchosen-ciphertext attack
- Contact author(s)
- schow @ cs nyu edu
- History
- 2010-03-06: last of 2 revisions
- 2009-05-04: received
- See all versions
- Short URL
- https://ia.cr/2009/189
- License
-
CC BY
BibTeX
@misc{cryptoeprint:2009/189,
author = {Sherman S. M. Chow and Jian Weng and Yanjiang Yang and Robert H. Deng},
title = {Efficient Unidirectional Proxy Re-Encryption},
howpublished = {Cryptology ePrint Archive, Paper 2009/189},
year = {2009},
note = {\url{https://eprint.iacr.org/2009/189}},
url = {https://eprint.iacr.org/2009/189}
}
