一种无证书签名方案的安全性分析及改进  

Security Analysis and Improvement of an Certificateless Signature Scheme

作　　者：潘帅[1] 高德智[1] 翟正元[1] 

机构地区：[1]山东科技大学信息科学与工程学院,山东青岛266590

出　　处：《计算机工程》2013年第5期156-159,164,共5页Computer Engineering

基　　金：青岛市科技发展计划基金资助项目(11-2-4-6-1-jch)

摘　　要：分析洪东招等人提出的无证书签名方案(计算机应用,2010年第7期),指出该方案不能抵抗公钥替换攻击和恶意的私钥产生器(PKG)攻击,同时采用由PKG生成用户公钥并公开的方法对方案进行改进。安全性分析结果表明改进方案可抵抗公钥替换攻击和恶意PKG攻击,并基于q-SDH问题和扩展逆计算Diffie-Hellman问题是困难的假设,在随机预言模型中证明该方案的安全性。This paper shows that Hong＇s efficient certificateless signature scheme is insecure against public key replacement attacks and malicious Private Key Generator（PKG） attacks. Aiming at these problems, the scheme is improved by the means that PKG generates the user＇s public key and makes it public. The analysis of security shows that the improved scheme is able to resist public key replacement attacks and malicious PKG attacks. Its security relies on the hardness of the q-Strong DiffieHellman（q-SDH） problem and Extended-Inverse-Computational Diffie-Hellman（E-Inv-CDH） problem. Under the random oracle model, the improved scheme is proved to be secure against existential forgery on adaptively chosen message attacks.

关 键 词：无证书签名 双线性对 q-SDH问题 公钥替换攻击 扩展逆计算Diffie—Hellman问题 恶意私钥产生器攻击 

分 类 号：TP309.2[自动化与计算机技术—计算机系统结构]