Abstract: Signcryption is a scheme that combines the signature and the encryption into one. Certificateless cryptosystem realizes the properties of the certificateless, and the key-unescrow. This paper combines the signcryption and certificateless public key cryptosystem on the basis of the existing literature and realizes an improved certificateless publicly verifiable signcryption scheme. Under the random oracle model, it is provable secure against two attackers defined in the paper. The pairings in unsigncryption is less a time than that of Malone-Lee J’s ID-based scheme and the efficiency is higher.

Key words: publicly verifiable, signcryption, Indistinguishability Chosen Ciphertext Attacks(IND-CCA)

摘要： 签密是将签名和加密相结合的一种方案，无证书密码体制实现无公钥证书且没有密钥托管的性质，该文在已有研究的基础上将签密和无证书公钥密码体制结合，实现一种改进的无证书可公开验证签密方案。在随机预言机模型下证明该方案可以抵抗文中定义的2种攻击。解签密中的对运算比Malone-Lee J的基于身份方案的对运算少1次，而且效率更高。

关键词: 可公开验证, 签密, 不可区分选择密文攻击

CLC Number: 

• TP309