关键词: 可搜索公钥加密, 关键词搜索, 关键词猜测攻击, 双线性对, 标准模型

Abstract: The previous Public key Encryption with Keyword Search（PEKS） framework and Secure Channel Free PEKS（SCF-PEKS） framework inherently suffer from the security vulnerabilities caused by the Keyword Guessing（KG） attack. To address this problem, a new framework called Secure Channel Free PEKS Without Designated Server（SCF-WDS-PEKS） is introduced. The SCF-WDS-PEKS framework has the merits of secure channel freeness and no designated server, while providing resistance to the KG attack. Under this framework, an efficient pairing-based SCF-WDS-PEKS scheme is developed. In the standard model, the proposed scheme is strictly proven to achieve the keyword ciphertext indistinguishability and the keyword trapdoor indistinguishability against adaptive chosen keyword attacks. Compared with some previous PEKS and SCF-PEKS schemes, it not only has the better properties, but also enjoys obvious advantage in both the computation efficiency and the communication cost.

Key words: searchable public key encryption, keyword search, keyword guessing attack, bilinear pairing, standard model