A Blockchain Based Searchable Encryption Scheme for Multiple Cloud Storage

摘要

Searchable encryption is a necessary and important service for cloud storage since it can realize the function of information retrieval on encrypted cloud data while protecting privacy. However, the typical searchable encryption models consisting of only a single cloud service provider can not prevent malicious behavior. In this paper, a new searchable encryption scheme in multi-cloud was proposed based on blockchain. We first define a system model based blockchain in multiple clouds and combine multiple cloud service providers together to store data together through a consortium chain. And then we store the encrypted document and document index in the 1PFS, at the same time the hash value of the documents and the IPFS address of the document are stored in blockchains. Our scheme can provide a sorting retrieval scheme based on multi-keywords over the outsourced encrypted data and a validation scheme to detect file integrity. The theoretical analysis and experiments on real-world data show the security and high performance of our scheme.