变色龙散列函数在代理签名方案中的应用

Application of chameleon hash function to proxy signature scheme

基于变色龙散列函数和离散对数签名方案(如DSA,Schnorr签名方案),给出一种新的代理签名方案,方案中代理人无须产生新的代理密钥,从而使代理人省去了管理和保护代理密钥的麻烦;同时,代理人只需找出给定变色龙散列值的碰撞即可产生代理签名．由安全性分析可知该方案是一个安全的代理保护的代理签名方案．

Based on a chameleon hash function and the signature scheme based on discrete logarithm（such as DSA and Schnorr signature schemes）, a new proxy signature scheme is proposed. In our scheme, the proxy signer need not generate the new proxy signing key, which overcomes the trouble in keeping and protecting the proxy signing key. At the same time, the proxy signer generate a proxy signature on behalf of the original signer by finding a collision to a given chameleon hash value. According to the security analysis, it is found that our scheme is a secure proxy-protected proxy signature scheme.