一个不可否认的门限代理签名方案的分析

Cryptanalysis of a Non-repudiable Threshold Proxy Signature Scheme

摘要: 指出HLL门限代理签名方案中存在错误并进行了更正,Tzeng、Tan、Yang提出的对HLL方案的攻击也都是错误的.更正后的HLL方案虽然能够抵抗Tzeng、Tan、Yang提出的来自原始签名者的伪造攻击,但不能抵抗部分代理签名者的联合伪造攻击,任何t个代理签名者联合起来,就能够伪造其他签名者的签名.

Abstract: TThe errors of HLL s nonrepudiable threshold proxy signature scheme are pointed out and corrected.The attacks to the HLL scheme proposed by Tzeng、Tan、Yang are not correct too.The corrected scheme is secure for forgery attacks from original signers,but it is insecure for unite forgery attacks from parts of proxy signers.Every t proxy signers can forge other signer s signature cooperatively