Attribute-based encryption with equality test (ABEET) simultaneously supports fine-grained access control on the encrypted data and plaintext message equality comparison without decrypting the ciphertexts. Recently, there have been several literatures about ABEET proposed. Nevertheless, most of them explore the ABEET schemes in the random oracle model, which has been pointed out to have many defects in practicality. The only existing ABEET scheme in the standard model, proposed by Wang et al., merely achieves the indistinguishable against chosen-plaintext attack security. Considering the aforementioned problems, in this paper, we propose the first direct adaptive chosen-ciphertext security ciphertext-policy ABEET scheme in the standard model. Our method only adopts a chameleon hash function and adds one dummy attribute to the access structure. Compared with the previous works, our scheme achieves the security improvement, ciphertext validity check and large universe. Besides, we further optimize our scheme to support the outsourced decryption. Finally, we first give the detailed theoretical analysis of our constructions in computation and storage costs, then we implement our constructions and carry out a series of experiments. Both results indicate that our constructions are more efficient in Setup and Trapdoor and have the shorter public parameters than the existing ABEET ones do.

中文翻译：

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大型Universe CCA2 CP-ABE在标准模型中具有相等性和有效性测试

具有相等性测试的基于属性的加密（ABEET）同时支持对加密数据进行细粒度的访问控制以及对明文消息进行相等性比较，而无需解密密文。近来，已经提出了一些关于ABEET的文献。尽管如此，他们中的大多数人还是在随机预言模型中探索ABEET方案，该方案已被指出在实用性方面存在许多缺陷。Wang等人提出的标准模型中唯一存在的ABEET方案。，仅在选择明文攻击安全性上难以实现。考虑到上述问题，本文在标准模型中提出了第一个直接自适应选择密文安全密文策略ABEET方案。我们的方法仅采用变色龙哈希函数，并向访问结构添加了一个虚拟属性。与以前的工作相比，我们的方案在安全性，密文有效性检查和大宇宙方面都得到了提高。此外，我们进一步优化了方案以支持外包解密。最后，我们首先对构建的计算和存储成本进行详细的理论分析，然后实施构建并进行一系列实验。