Abstract: Certificate-based public key cryptology needs to certify user’s public key. It not only simplifies the process of certificate management in traditional public key cryptology, but also overcomes the problem of key-escrow in ID-based cryptology. In random oracle model, based on discrete logarithm problem, inverse-Diffie-Hellman problem and computational Diffie-Hellman problem, a certificate-based signature scheme is proposed which is proven secure. The scheme only needs a bilinear pairing and a pre-computing, so it is more efficient than the available certificate-based signature schemes.

Key words: certificate-based signature, random oracle model, discrete logarithm problem, Computational Diffie-Hellman problem, Inverse Diffie-Hellman problem, existential unforgeability

摘要： 基于证书的公钥密码体制需要对用户的公钥进行认证，简化了传统的公钥密码系统中的证书管理过程，也克服了基于身份密码体制中存在的密钥托管问题。在随机预言机模型下，基于离散对数问题（DLP），逆Diffie-Hellman问题（Inv-DHP）和计算性Diffie-Hellman问题（CDHP）构造了一个基于证书的签名方案，证明了它是存在性不可伪造的。该方案的算法只需要一个双线性对运算和一个预运算，在效率上优于已有的基于证书签名方案。

关键词: 基于证书签名, 随机预言机模型, 离散对数问题, 计算性Diffie-Hellman（CDH）问题, 逆Diffie-Hellman（Inv-DH）问题, 存在性不可伪造