Provably secure certificateless strong designated verifier signature scheme based on elliptic curve bilinear pairings

Abstract

Diffie and Hellman first invented the public key cryptosystem (PKC) wherein the public key infrastructure (PKI) is used for the management of public keys; however, the PKI-based cryptosystems suffer from heavy management trouble of public keys and certificates. An alternative solution to the PKI is Shamir’s identity-based cryptosystems (IBC), which eliminate the need of public key certificates; however, the most important shortcoming of IBC is the key escrow problem. To cope with these problems, Al-Riyami and Paterson proposed a novel scheme of certificateless PKC (CL-PKC) by combining the advantages of PKI and IBC. Since then, several certificateless signature schemes have been designed and most of them have been analyzed and proven insecure against different types of adversaries. Besides, the researchers have given very less attention to the certificateless strong designated verifier signature (CL-SDVS) scheme. Therefore, we proposed a CL-SDVS scheme using elliptic curve bilinear parings in this paper. Our scheme, which is provably secure in the random oracle model with the intractability of BDH and CDH assumptions, supports all desirable security necessities of the CL-SDVS scheme such as strongness, source hiding and non-delegatability. The rigorous security analysis and comparison with others guarantee the better performance of the proposed scheme.