摘要： 在基于身份的高效无证书签名方案中，签名者在生成签名时既不受公钥证书认证的约束，又无需PKG为其生成基于身份的部分公钥，从而导致任何人均可伪造其他人的签名。针对该问题，给出安全的无证书签名方案必须具备的一个条件，并对原方案做出改进。改进后的方案保持了原方案高效的优点且安全性更高。

关键词: 无证书签名方案, 基于身份的密码系统, 密钥托管, 双线性对

Abstract: In the efficient ID-based certificateless signature scheme, the signer can produce a valid signature without the constraint of public key authentication and the partial private key generated by trusted PKG at the same time. The attacker can forge anyone else’s signature. Aiming at this problem, this paper presents an essential condition for a secure certificateless signature scheme and two corresponding efficient improved signatures are obtained. The improved signature scheme keeps the characters of high efficient and achieves higher safety level.

Key words: certificateless signature scheme, ID-based cryptosystem, key escrow, bilinear paring

中图分类号: 

• TP309