身份类加密体制的双线性对主线和格主线类比设计

Identity related encryption (IRE) consists of many novel cryptographic primitives closely related to traditional identity based encryption. Until now, there are mainly two ways to design and analyze IRE in terms of the employed mathematical tool. One is to design IRE with bilinear pairings and the other is to design IRE with lattices. These two ways can be seen as two backbones of the entire IRE research field. Many pairing based techniques for designing IRE are rapidly developing, while there are only a few results on designing IRE based on lattices. Furthermore, the achievements on designing IRE by learning between the two backbones are rare. Clearly, these "learning" can give us new perspectives on how to design IRE. Firstly, we shall design new pairing based IRE schemes by using pairing based techniques or by learning from lattice based techniques. Secondly, through learning from the pairing based techniques or using the lattice based techniques, new lattice based IRE schemes will be constructed. Concretely, on the pairing backbone, we shall design new pairing based IBE, new fully secure IRE, new types of functional encryption, DPVS based novel IRE, new pairing based IRE by learning from the lattice cryptography. On the lattice backbone, we shall design new lattice based IRE, idea lattice based IRE, fully secure lattice based IRE, new lattice based IRE by learning from the pairing based cryptography. Furthermore, we shall design IB-(L)TDF based new IRE schemes too. Analogical construction is the main feature of our research method. Through our research, we hope to more deeply and extensively develop the theory on analogical construction of IRE, solve some important open problems like construction of fully secure lattice based IRE etc.

身份类加密体制的设计与分析由双线性对和格两条主线贯穿。双线性对主线上，构造技术方兴未艾；格主线上，成果尚不多见。两条主线之间相互借鉴的研究还很欠缺，它们的类比构造将为身份类加密的研究提供新的增长点。研究内容：利用双线性对自有技术，或借鉴格上的关键技术尤其是向量化技术，设计与分析双线性对上新型身份类加密方案；利用格自有技术，或借鉴双线性对上的关键技术，设计与分析新型格身份类加密方案。研究目标：设计双线性对上新型IBE、新型全安全身份类加密、新型功能加密、基于DPVS的新型身份类加密、仿格的双线性对身份类加密方案；设计格上的新型身份类加密、基于理想格的身份类加密、仿双线性对的格身份类加密、全安全的格身份类加密方案；利用IB-(L)TDF设计新型身份类加密方案。研究方法上强调方案和关键技术的类比构造。原创性成果是系统地提出身份类加密体制的类比设计理论，解决格身份类加密体制的全安全等公开问题。

一、利用双线性对自有技术或借鉴格上关键技术，设计与分析双线性对上新型身份类加密方案。.1、IBE效率提升和性质扩展。①基于IEEE标准化的IBE方案，构建了PRE方案，达到主密钥安全性和不可转移性；②基于双线性对，设计了属性签密方案，密文长度固定，解签密运算量8p+(n+3)e；③提出了1种高效模糊属性基签密方案，满足可公开验证性，且密文较短。.2、借鉴DPVS、DSE技术，利用IB-(L)TDF工具，设计全安全的身份类加密方案。①利用对偶加密系统构造了高效属性基加密方案，对研究选择性安全模型与全安全模型之间的关系具有重要参考价值；②基于Cramer-Shoup加密，提出了1种高效的CCA安全代理重加密方案，可抵抗DDOS攻击；③提出了1种全安全的属性基加密方案，允许用户私钥在非单调的访问结构上表达。.3、功能性设计和应用扩展。①提出了1种属性可撤销的属性加密方案，密钥长度固定；②利用私钥置换技术，构造了密钥隐私的全同态代理重加密方案；③提出了1种适用大数据的属性基广义签密方案。.二、利用格自有技术或借鉴双线性对上的关键技术，设计与分析格上新型身份类加密方案。.1、效率更高的格身份类加密体制。①在标准模型下，提出了1种基于R-LWE的FIBE方案，公钥长度短、密文扩展率低；②改进了理想格上陷门生成函数，提出1种高效HIBE方案；③设计了2种高效理想格上IND-sID-CPA安全的基本IBE密码系统。.2、充分利用格上快速陷门函数的优势，设计格上新型身份类加密体制。①利用GPV签名,构造了1种能够抵抗陷害攻击，且能够有效进行群成员加入和撤销的格上群签名方案；②给出了后向抗合谋攻击安全的定义，构造了1种满足该性质的格上PRE方案；③通过在密钥生成过程中添加适当的扰动，隐藏了被代理者的真实私钥，设计了1种抗合谋攻击安全的格上PRE方案。.发表论文30余篇，其中SCI 检索10篇，EI检索20篇，核心技术申报专利3项。培养青年教师5名、研究生16名，出版译著1部。