A Multi-keyword Multi-user Searchable Encryption Scheme Based on Cloud Storage

With the development of cloud computing, the huge growth of data from electronic business or social network leads to a trend that the owners of data are inclined to outsource their data (usually encrypted) to cloud storage servers. Leveraging searchable encryption technologies can not only guarantee the confidentiality and integrity of the data, but also achieve an effective search on encrypted data. Compared with the single keyword search, the multi-keyword search has an important practical significance for its more precise retrieval of data. Meanwhile, aimed at the defects in existing searchable encryption schemes, such as the unsatisfactory search efficiency and no support for multi-user search, etc., in this paper, we propose a multi-keyword multi-user searchable encryption scheme based on cloud storage, which is realized through secure interactions between authorized users and cloud severs. Our proposal adopts the encryption of exponent which is realized through secure interactions between authorized users and cloud severs involved generation of secure trapdoor and is of indistinguishability against adaptive chosen keyword attack (IND-CKA). Subsequently, theoretical and empirical evaluations demonstrate the desirable retrieval efficiency of our proposal compared with current methods. And meanwhile, our proposal achieves the access controllability of the encrypted data, and is of dynamic addition and revocation of authorized users, at the same time is of dynamic update of the user accessing to files.