传统的数字签名方案存在证书的存储和管理开销大的问题,基于身份的数字签名方案无法解决其固有的密钥托管问题,而无证书签名方案不需使用公钥证书,而且没有密钥托管问题,是目前的一个研究热点。基于双线性映射设计出一个无证书签名方案,并在随机预言机模型下证明了它的安全性。该无证书签名方案在签名和验证阶段共需要两个双线性映射运算,具有较高的执行效率。签名方案的安全性建立在计算Diffie-Hellman问题的困难性假设上。性能分析表明,设计的签名方案在保证安全性的前提下,具有较高的执行效率。
The traditional digital signature schemes need much more storage and management costs for the effective use of certificates,while the identity-based digital signature schemes fail to solve the inherent key-escrow problem.Certificateless signature schemes can sign and verify with no certificates and they do not suffer from the key-escrow problem,and so certificateless signature schemes have received much more attention recently.This paper proposes a certificateless signature scheme from bilinear pairings,and verifies its security under the random oracle machine.The certificateless signature scheme needs only two bilinear pairing operations in the signing and verifying phases.The security of the signature scheme is under the assumption of the computational Diffie-Hellman problem.The performance analysis shows that this scheme is much more efficient than other previous signature schemes.