Abstract: Under the cloud computing environment, the attribute-based encryption multi-keyword searchable encryption can realize access control and searchability of encrypted data at the same time. For improving the retrieval efficiency of encrypted databases and reducing the cost of file keyword retrieval index storage, this article proposes an attribute-based multi-keyword search scheme based on Bloom filters. First, for the keywords set of a file, the Bloom filter is used to generate a fixed length index vector corresponding to the keyword set, so as to reduce the storage complexity of the keyword index. Besides, in order to prevent the adversary from obtaining the keywords information by means of statistical analysis of the index, this paper uses a permutation to randomize the elements of the index vector, and uses the attribute-based encryption to share the permutation. Thus, only legitimate users can obtain the permutation and construct a trapdoor for querying keywords with the permutation. Finally, through the security analysis and experimental analysis, the security, efficiency and practicability of this scheme are showed.

Key words: cloud computing, attribute-based encryption, Bloom filter, permutation, keyword search