基于身份的代理盲签名方案分析与改进

Analysis and Improvement of Identity-based Proxy Blind Signature Scheme

通过对一种基于身份的代理盲签名方案的分析,指出该方案并不满足不可伪造性,代理人通过计算原始签名人的私钥,可以伪造原始签名人的签名或任何授权,且原方案有关签名盲性的证明存在错误。在此基础上提出一种改进的代理盲签名方案,克服了原方案的安全缺陷,有效防止代理人恶意的伪造攻击,且保留了原方案的其他优点。

The identity-based proxy blind signature scheme proposed is analyzed,and it is found that their scheme does not possess the unforgeability property.Because the proxy signer can recover the original signer’s private key,one can forge the signing capabilities of the original signer.At the same time,it is found there is mistake about the process of proving their signature scheme satisfying blindness.An improved proxy blind signature scheme is proposed,which can resolve the security problems existing in the original scheme.Analysis indicates that improved proxy blind signature scheme is secure against the proxy signer’s forgery attack,and remains other merit of the original scheme.