Authors: Fei Yan; Xiaofeng Chen; Yinghui Zhang
Addresses: State Key Laboratory of Integrated Service Networks (ISN), Xidian University, Xi'an 710071, China ' State Key Laboratory of Integrated Service Networks (ISN), Xidian University, Xi'an 710071, China ' State Key Laboratory of Integrated Service Networks (ISN), Xidian University, Xi'an 710071, China
Abstract: An online/offline signcryption scheme provides confidentiality and authentication simultaneously, and it is particularly suitable for the application of resource-constrained systems. In this paper, we present a key-exposure free online/offline signcryption scheme. In contrast, it seems that all the existing online/offline signcryption schemes based on Shamir-Tauman's paradigm suffer from the key exposure problem. In the random oracle model, the proposed scheme is proved to be indistinguishable against adaptive chosen-ciphertext attacks (IND-CCA2) and existentially unforgeable against chosen-message attacks (EUF-CMA). Besides, an improved scheme is proposed, which requires none of the recipient's public information in the offline phase and hence makes practical sense.
Keywords: online signcryption; offline signcryption; key exposure; chameleon hash function; confidentiality; authentication; security; random oracle model; chosen-ciphertext attacks; chosen-message attacks; encryption; cryptography.
International Journal of Grid and Utility Computing, 2013 Vol.4 No.1, pp.85 - 93
Received: 04 Jul 2012
Accepted: 06 Jul 2012
Published online: 16 Jun 2013 *