中文摘要：

安全广播服务已经成为信息安全领域的一个研究热点,而多接收者签密技术被认为是实现安全广播的最有效方法之一,因此对多接收者签密机制的研究已成为信息安全领域的一个新分支.针对现有使用双线性映射的多接收者签密机制存在计算效率低的不足,同时为了满足广播通信环境下发送者的多消息发送需求,文中提出不使用双线性映射的无证书多接收者多消息签密机制,签密密文中不再包含接收者身份列表,实现对接收者身份等隐私信息的保护;并且具有密文解密的独立性,同时发送者可在一次签密操作中完成多消息发送任务.安全性证明及正确性分析表明文中机制是安全、有效的无证书多接收者多消息签密机制,由于未使用双线性映射等计算量较大的运算,文中方案的计算效率更高.与现有方案相比较而言,除具有保密性和不可伪造性之外,文中方案具有较强的匿名性及计算效率,满足广播通信环境中多消息的匿名发送需求.

英文摘要：

Signcryption is a cryptographic primitive that fulfills both the functions of digital signature and public key encryption simultaneously, at a cost significantly lower than that required by the traditional signature-then-encryption approach. Secure broadcasting service become more and more attractive and it has become a hot research topic in the field of information security. The multi-receiver signcryption technology is considered as one of the most efficient methods to implement secure broadcasting, and it has become a new branch of information security. In addition, the certificateless public key cryptography eliminates certificate management in traditional public key infrastructure and solves the key escrow problem in identity-based cryptography. Certificateless signcryption is one of the most important primitives in certificateless public key cryptography which achieves confidentiality and authentication simultaneously. In this paper, in order to satisfy the receivers＇ need of privacy protection, the multi-receiver and multi-message of certificateless signcryption scheme was proposed. The signcryption ciphertext no longer contains receivers＇identity list to protect receivers~ privacy. And, as well, the public information set guarantees the independency of decryption. The proofness of correctness and safety demonstrates this signcryption scheme is safe and effective. Apart from confidentiality and unforgery, this signcryption scheme is better in anonymity and has a higher computational efficiency, satisfy the needs of sending sensitive information in broadcast communication environment.