完美前向安全的基于身份认证密钥协商方案

现有的基于身份的一轮认证密钥协商方案没能实现强的完美前向性.采用强不可伪造的签名算法对临时公钥进行签名,提出一种改进的基于身份认证密钥协商方案.首先,对Boneh和Boyen提出的强不可伪造的短签名方案进行改造,提出一种强不可伪造的基于身份签名方案;然后,将新签名方案与Ni等人提出的eCK安全的基于身份一轮认证密钥协商方案相结合,提出新的密钥协商方案.进一步,为了实现新方案的可证明安全性,在对比分析eCK-PFS模型和eCK模型的基础上,融合现有安全模型,定义了基于身份认证密钥协商方案分析的强安全模型ID-eCK-PFS.在ID-eCK-PFS模型下,通过安全性规约,证明了新提出的基于身份认证密钥协商方案实现了强安全性,包括抗密钥泄露伪装、抗临时秘密泄露和完美前向安全性等.

An Identity-based Authenticated Key Agreement Scheme with Perfect Forward Secrecy

The existing identity-based one-round key agreement protocols fail to achieve strong perfect forward secrecy(PFS).An expanded identity-based authenticated key agreement scheme is proposed,where a temporary public key is bound to an identity by using a strongly existentially unforgeable signature algorithm.In the new proposed scheme,an eCK secure key exchange protocol proposed by Ni et al.is combined with a strongly unforgeable identity-based signature scheme that was extended from the short signature proposed by Boneh and Boyen.Then,based on the comparative analysis of the eCK-PFS model and the eCK model,a strong security model,named ID-eCK-PFS,is defined,which merged the existing security models.Under the ID-eCK-PFS model,it is shown that the proposed scheme achieves the provable and strong security,including key-compromise impersonation(KCI)resilience,ephemeral secrets reveal(ESR)resistance,and perfect forward secrecy.