支持非单调访问结构的可验证搜索属性加密方案

针对属性基密文搜索方案多数只支持单调访问结构，且对搜索结果缺乏有效检验等问题，提出支持非单调访问结构且搜索可验证的密文关键字搜索属性加密方案。首先，由属性值构造多项式，根据多项式整除性质实现密文细粒度搜索的权限设置；然后，在确保不泄露隐私信息的前提下，由云服务器完成密文搜索和外包解密；最后，借助所提承诺方案实现对搜索结果的正确性检验。所提方案支持非单调访问结构且具备密文细粒度搜索、数据共享、外包解密和搜索可验证等多项功能。在随机预言机模型中，基于扩展多指数序列判定Diffie-Hellman （aMSE-DDH）假设，可证明该方案在选择密文攻击和选择关键字攻击情况下均具有选择性的不可区分安全性。实验结果表明，所提方案的终端解密时间与属性个数无关，仅需约12.9 ms。

Attribute-based encryption scheme with verifiable search and non-monotonic access structure

Most existing attribute-based keyword search schemes only support monotonic access structure and lack efficient verification for search results. Aiming at these problems， a ciphertext keyword search attribute-based encryption scheme with verifiable search and non-monotonic access structure was proposed. Firstly， the polynomials were constructed by the attribute values， and the fine-grained ciphertext search permission setting was accomplished by divisibility property of the polynomials. Then， both keyword search and outsourced decryption were performed by the cloud servicer without revealing any private information. Finally， the search result verification was realized by utilizing the proposed commitment scheme. The proposed scheme supports multiple functions such as non-monotonic access structure， fine-grained search， data sharing， outsourced decryption， and verifiable search. Under the augmented Multi-Sequence of Exponents Decisional Diffie-Hellman （aMSE-DDH） assumption， it can be proved that this scheme has selective indistinguishability security under chosen ciphertext attacks and under chosen keyword attacks， respectively， in the random oracle model. Experimental results show that the terminal decryption time of the proposed scheme is not related to the attribute number， and is about 12.9 ms.