基于身份密钥交换的安全模型

Security model for ID-based key exchange

研究了基于身份的密钥交换协议的可证明安全问题。在通用可组合安全框架下,提出了基于身份密钥交换协议的模型。在攻击模型中,添加了攻陷密钥生成中心的能力。根据基于身份密钥交换的特点,设计了基于身份密钥交换的理想函数。在新的攻击模型和理想函数下,提出的模型既保证了基于身份密钥交换的通用可组合安全性,又保证了一个重要的安全属性——密钥生成中心前向保密性。此外,带有密钥确认属性的Chen-Kudla协议可以安全实现基于身份密钥交换的理想函数。

The provable security of ID-based key exchange protocols was investigated. In the universally composable framework, the provable secure model of ID-based key exchange was proposed. The ability of the adversary to corrupt key generation center was added to the adversary model. According to the characteristics of ID-based key exchange, the ideal functionality of ID-based key exchange was presented. Based on the adversary model and the ideal functionality, the proposed model captures not only the universally composable security of ID-based key exchange, but also implies one of the important properties of ID-based key exchange——key generation center forward secrecy. In addition, the protocol （with key confirmation） proposed by Chen and Kudla can securely realize the functionality of ID-based KE with KGC-FS.