摘要: 对李继国等人提出的基于身份的高效签名方案(计算机学报,2009年第11期)进行分析,以一个具体的攻击方法,证明任何攻击者都可以伪造任意消息关于任意身份的有效签名,因此方案不满足存在不可伪造性。通过将原方案中签名的一个分量值固定,并将其作为用户的公钥,使方案在保证效率的同时,满足存在不可伪造性。
关键词:
密码学,
基于身份的签名方案,
数字签名,
双线性对,
密码分析
Abstract: This paper concludes that the efficient identity-based signature scheme proposed by Li Jiguo et al is insecure, and gives an attack method, which shows that any attacker can forge a valid signature on any message with respect to any identity. Therefore, Li Jiguo’s scheme does not satisfy existential unforgeability. By making a component of a signature as user’s public key, an improved scheme is proposed, which does not reduce the efficiency of Li Jiguo et al’s scheme while satisfying the existential unforgeability.
Key words:
cryptography,
identity-based signature scheme,
digital signature,
bilinear pairings,
cryptanalysis
中图分类号:
黄斌, 史亮, 邓小鸿. 一种基于身份的签名方案密码分析与改进[J]. 计算机工程, 2012, 38(24): 108-110.
HUANG Bin, SHI Liang, DENG Xiao-Hong. Cryptanalysis and Improvement of an Identity-based Signature Scheme[J]. Computer Engineering, 2012, 38(24): 108-110.