基于ECC存在特权集的(t,n)门限群代理多重签名方案

为了解决门限群签名方案中联合攻击、伪造攻击、权限、抵赖等问题,本文基于hash函数的单向性、椭圆曲线离散对数问题的难解性,结合Shamir(t,n)门限方案,提出了一种基于ECC存在特权集的(t,n)门限群代理多重签名方案,满足((t1’,n1';t1,n1)(t2’,n2';t2,n2))门限特性.该方案利用公钥环境下交互式身份验证的方法,增加成员认证密钥,有效防止密钥管理中心和签名服务者的串通陷害;签名者通过等式验证密钥管理中心分配的秘密份额是否有效;代理授权份额的生成由原始签名者和代理签名者共同完成,单个签名的生成使用了签名者的私钥和随机数,有效防范抵赖.安全性分析表明,该方案具有抗联合攻击、强不可伪造性、门限特性和匿名性等特点,满足门限群代理签名应有的性质.

A (t,n) threshold group-proxy multi-signature scheme with privilege subsets based on ECC

In order to solve the problems of joint attack,forgery attack,permissions and denial in the threshold group signature scheme,this paper puts forward a (t,n) threshold group-proxy multisignature scheme with privilege subsets of ECC,based on the unidirectional hash function and the intractability of the elliptic curve discrete logarithm problem,and combined with Shamir (t,n) threshold scheme,which meets the features of ((t1',n1';t1,n1) (t2',n2';t2,n2)) threshold.By means of interactive authentication under the public key environment,the scheme adds the member authentication key so as to effectively prevent the collusion between key management center and signature server.The signer verifies whether the secret share distributed by management center is effective through the equation;the agent authorized share is generated by the original signer and the proxy signer together,and the single signature is produced by using the signer's private key and random numbers,and this effectively prevent denial.The safety analysis shows that the scheme has merits of resisting the joint strikes,strong unforgeability,threshold peculiarity and anonymity,and it can meet the due nature of threshold group-proxy signature.