摘要： 在基于时间戳撤销机制的代理签名方案中，授权服务器(AS)签发的时间戳内并不包含原始签名人的授权信息，使攻击者可以利用该缺陷绕过AS检查，获得合法的时间戳签名。为此，对AS生成时间戳阶段进行改进，使攻击者无法获得能够通过验证的时间戳签名，从而弥补原方案的安全缺陷。

关键词: 代理签名, 撤销, 时间戳, 原始签名者, 代理签名者

Abstract: According to in-depth security analyzing of a proxy signature scheme with revocation by the use of timestamp, it points out that the malicious proxy signer can obtain a valid timestamp whatever the original signer revoked the delegation or not because the time-stamp issued by Authentication Sserver(AS) do not bind with the delegation of original signer. Pointing at the problems existed in the timestamp generation phase, this paper proposes a more efficient scheme with fast revocation, which solves the weaknesses of original scheme fundamentally.

Key words: proxy signature, revocation, timestamp, original signer, proxy signer

中图分类号: 

• TP309