In public key encryption with keyword search (PEKS), a secure channel is required in order to send trapdoors to the server, whereas in secure-channel free PEKS (SCF-PEKS), no such secure channel is required. In this paper, we propose a generic construction of SCF-PEKS with multiple keywords (SCF-MPEKS) from hidden vector encryption, tag-based encryption, and a one-time signature. Our generic construction provides adaptive security, where the test queries are allowed in the security model, and does not require random oracles. In addition to providing an instantiation of our generic construction, which is the first adaptive secure SCF-MPEKS scheme in the standard model, we implement the SCF-MPEKS scheme by using the PBC library. Moreover, we extend the Boneh-Waters range search technique, and show that the running time of our encryption algorithm is approximately twice as fast as that of the Boneh-Waters encryption algorithm.

在带有关键字搜索（PEKS）的公钥加密中，需要一个安全通道才能将活板门发送到服务器，而在安全通道免费的PEKS（SCF-PEKS）中，则不需要这样的安全通道。在本文中，我们提出了一种具有多个关键字（SCF-MPEKS）的SCF-PEKS的通用构造，这些关键字来自隐藏矢量加密，基于标记的加密和一次性签名。我们的通用构造提供了自适应安全性，其中安全模型中允许测试查询，并且不需要随机预言。除了提供通用构造的实例化（这是标准模型中的第一个自适应安全SCF-MPEKS方案）之外，我们还使用PBC库来实现SCF-MPEKS方案。此外，我们扩展了Boneh-Waters范围搜索技术，