无双线性对的可证安全的高效的代理签名方案

Provable Secure and Efficient Proxy Signature Scheme without Bilinear Pairings

目前已提出的代理签名方案存在两个问题,首先缺乏在完整的代理签名安全模型下证明方案的安全性;其次一些安全性可归约于CDH问题或者其他问题的方案都含有双线性对的计算,由于双线性对的计算需要较多的时间,因此这些方案的计算性能不高.本文在EDL签名方案的基础上提出一种新的代理签名方案—Proxy-EDL签名方案,该方案是对EDL签名方案的扩展,方案中没有双线性对的计算,具有较高的计算性能,同时新方案在代理签名安全模型下被证明具有在自适应选择消息攻击下存在代理签名不可伪造性,其安全性可归约于CDH问题.与目前已有的代理签名方案相比,本文的代理签名方案具有更高的安全性和更好的计算性能.

There are two major problems in the existing proxy signature schemes. Firstly, the existing proxy signature schemes are not proved for their security in the intact provable security model for proxy signature. Secondly, some proxy signature schemes which have security reduction to CDHP or other problems are based on bilinear pairing operation, but bilinear pairing operation needs much time, so the schemes have low computational efficiency. In this paper, we show a new proxy signature scheme based on the EDL sig- nature scheme--Proxy-EDL signature scheme. The new scheme is an extension of the EDL signature scheme, which is not based on bilinear pairing operation, so the new scheme has high computational efficiency. And the new scheme is proved to have the existential proxy signature unforgerability under an adaptive chosen message attack in the provable security model for proxy signature, which has a security reduction to CDHP. Comparing with other existing proxy signature schemes, the new scheme is more efficient and secure.