基于双线性对的前向安全的代理盲签名方案

FORWARD SECURE PROXY BLIND SIGNATURE SCHEME BASED ON BILINEAR PAIRING

通过对魏俊懿等人提出的一种前向安全的无证书代理盲签名方案(W-Y方案)进行分析,指出该方案不具有前向安全性和不可伪造性,并且攻击者在获取代理密钥后可以伪造未来时段的代理签名。提出一种改进方案,新方案不需要密钥生成中心(PKG)参与用户密钥生成,克服了W-Y方案的安全漏洞,具有前向安全性和后向安全性:即使代理密钥被泄露,攻击者也无法伪造过去和未来时段的代理签名。

By analysing the forward secure certificateless proxy signature scheme （W-Y scheme） proposed by Wei et al, we point out that the scheme is neither unforgeable aor forward secure, and the malicious attackers can forge the proxy signature of the future, period after obtaining the proxy key. An improved scheme is proposed. In new scheme, the private key generator （PKG） is not involved in the generation of user＇s key, and it overcomes the security drawbacks of W-Y scheme as well, so holds both the forward and backward securities：even if the proxy key is let out, the attackers are still not able to forge the proxy signature of the periods of past and future.