通过对鲁荣波等人提出的新型代理签名方案进行分析,指出该方案不满足公钥替换攻击,并给出了攻击方法。在此基础上提出一种改进的代理签名方案,克服了原方案的安全缺陷,有效地防止原始签名人的伪造攻击。与原方案相比,改进的方案在效率不变的情况下具有更高的安全性。
In this paper, a new proxy signature scheme proposed by Lu Rong-bo et al. is given a detailed cryptanalysis. This paper points out that this scheme is not secure against public key substitution attack and proposes a method to attack the new scheme. Based on this, one improved scheme is given and concluded that it is not only secure against the original signer' s forgery attack effectively but also avoiding the problems of the original scheme. Compared with the original scheme, the new scheme is more security and has the same computation complexity.