Public key authenticated encryption with multiple keywords search using Mamdani system

The public cloud environment has attracted massive attackers to exploit insecure ports and access to data, services and other resources. Techniques, such as Public Key Encryption with Keyword Search (PEKS), could be deployed in cloud security to avoid accidents. PEKS allows users to search encrypted documents by a specific keyword without compromising the original data security. The first PEKS scheme was proposed in 2004, since then, PEKS has been experienced a great progress. Recently, Kazemian and Ma firstly incorporated with Fuzzy Logic technique to PEKS scheme, namely \Public Key Encryption with Multi-keywords Search using Mamdani System (m-PEMKS)", in order to support Fuzzy Keyword (i.e. \latest", \biggest") Search. However, the m-PEMKS scheme has the ability to prevent Offline Keyword Guessing Attack (OKGA) but it may suffer Inside Keyword Guessing Attack (IKGA). This paper will revisit the m-PEMKS scheme and propose a robust m-PEMKS mechanism. The proposed scheme has the properties of Ciphertext Indistinguishability, Trapdoor Indistinguishability and User Authentication which can prevent OKGA and IKGA. Besides, the proposed scheme supports both Fuzzy Keyword Search and Multiple Keywords Search and therefore, it is more practical and could be applied to the general public networks