中文摘要：

混合签密能够处理任意长度的消息,而公钥签密则不能.文中将混合签密技术扩展到无证书环境,构建了一个可证明安全的无证书混合签密方案.随机预言模型下,作者证明,所提方案在双线性Diffie-Hellman问题和计算性Diffie-Hellman问题的难解性下,满足自适应选择密文攻击下的不可区分性和自适应选择消息攻击下的不可伪造性.文中方案计算复杂度低,适合于实际应用.

英文摘要：

Hybrid signcryption can process the messages of arbitrary length, while public key signcryption cannot. In this paper, we extend hybrid signcryption technique to the certificateless setting, and construct a provably secure certificateless hybrid signcryption （PS-CLHS） scheme. In the random oracle model, we prove that the proposed scheme satisfies the indistinguishability against adaptive chosen-ciphertext attacks and unforgeability against adaptive chosen-message attacks under the hardness of the bilinear Diffie-Hellman problem and computational Diffie-Hellman problem. In addition, this scheme has lower computational complexity and is appropriate to applications in practice.