可抵抗恶意私钥中心的无证书公钥加密方案

Certificateless Public Key Encryption Scheme Against Malicious KGC Attack

目前,大多数基于无证书的加密方案和签名方案的构造方法都忽视了恶意私钥中心的攻击,如何设计一个有效的可抵抗恶意私钥中心的无证书密码系统是研究热点.通过对原始的无证书加密方案顺序的改变,利用双线性映射构造了一个高效的可以抵抗恶意私钥中心的无证书加密方案.在方案中,加密过程只需一次幂运算,解密过程仅需一个对运算.与已有的方案相比具有很高的效率.方案安全性基于计算Diffie-Hellman问题和P-双线性Diffie-Hellman Inversion问题,并在随机预言模型下对用该方法所构造的方案的安全性进行了证明.

Recently, most of the certificateless public key encryption scheme and signature scheme neglect the attack from malicious KGC, so how to design an effective certificateless public key encryption to resist the malicious KGC attack is an interesting research topic. In this paper, by adjusting the steps of original certificateless public key encryption, an efficient certificateless public key en- cryption scheme using bilinear maps is put forward, which can against the malicious KGC attack. The encryption algorithm only need one power computation and the decryption only need one paring computation. Therefore, the scheme is more efficient than other exi- ting scheme. Additionally, under the random oracle model, the security reaches chosen-ciphertext secure assuming the computing Dif- fie-Hellman and p-Bilinear Diffie-Hellman Inversion problems are difficult.