School of Information and Software Engineering, University of Electronic Science and Technology of China, No. 4, North Jianshe Road, Chenghua District, Chengdu, Sichuan 610054, China.
Math Biosci Eng. 2019 May 5;16(5):3914-3935. doi: 10.3934/mbe.2019193.
Public Key Encryption with Keyword Search (PEKS) is a desirable technique to provide searchable functionality over encrypted data in public key settings, which allows a user to delegate a third party server to perform the search operation on encrypted data by means of keyword search trapdoor without learning about the data. However, the existing PEKS schemes cannot be directly applied to practice due to keyword guessing attack or the absence of a mechanism to limit the lifetime of a trapdoor. By addressing these issues at the same time, this paper presents a Public Key Encryption Scheme with Temporary and Fuzzy Keyword Search (PETFKS) by using a fuzzy function and an encryption tree. The proposed PETFKS scheme is proven adaptively secure concerning keyword confidentiality and backward and forward secrecy in the random oracle model under the Bilinear Di e-Hellman assumption. Moreover, it is also proven selectively secure with regard to the resistance of keyword guessing attack. Furthermore, the security and e ciency analyses of the proposed scheme are provided by comparing to the related works. The analyses indicate that the proposed scheme makes a threefold contribution to the practical application of public key encryption with keyword search, namely o ering secure search operation, limiting the lifetime of a trapdoor and enabling secure time-dependent data retrieval.
公钥加密带关键字搜索（PEKS）是一种在公钥环境中为加密数据提供可搜索功能的理想技术，它允许用户通过关键字搜索陷门将搜索操作委托给第三方服务器，而无需了解数据。然而，由于关键字猜测攻击或缺乏限制陷门生命周期的机制，现有的 PEKS 方案无法直接应用于实际。本文通过使用模糊函数和加密树同时解决这些问题，提出了一种带临时和模糊关键字搜索的公钥加密方案（PETFKS）。在所提出的 PETFKS 方案中，在随机 oracle 模型下基于双线性 Di e-Hellman 假设，证明了关于关键字机密性以及后向和前向机密性的适应性安全性。此外，它还通过抵抗关键字猜测攻击的选择性安全性得到证明。此外，通过与相关工作进行比较，对所提出方案的安全性和效率进行了分析。分析表明，所提出的方案在公钥加密带关键字搜索的实际应用中做出了三重贡献，即提供安全的搜索操作、限制陷门的生命周期以及实现安全的与时间相关的数据检索。
