适用于电子认证的高效无证书混合签密方案

An Efficient Certicateless Hybrid Signcryption Scheme for Electronic Authentication

无证书混合签密解决了证书管理问题、密钥托管问题,具有能够处理任意长度消息等多重优势,适用于电子认证领域.对Sun提出的高效签密方案进行了分析,发现其不满足不可抵赖性和可公开验证性.提出了一个改进的无证书混合签密方案,新方案满足不可抵赖性、公开验证性以及前向安全性,同时保持了原方案的高效性.在随机预言模型中,基于双线性Diffie-Hellman问题和计算Diffie-Hellman问题对新方案进行了证明.

Certificateless hybrid signcryption can solve the problem of the management of CA in public key encryption system and key trustee in the IBE encryption system. It also can handle messages of arbitrary length, which is applicable to electronic authentication. Analysis of the scheme proposed by Sun shows that the scheme can't resist dishonest recipient's forgery attack and can't achieve public verification. This paper proposed an improved signcryption scheme to overcome these security problems, which satisfies undeniable, verifiability and forward security, and keeps its high efficiency. The improved scheme was proven to be secure under BDH assumption and CDH assumption in the random oracle model.