Attribute Revocable Data Sharing Scheme Based on Blockchain and CP-ABE.

Data sharing and exchange is an effective way to release the vitality and value of data resources, but it also brings security problems, especially in the distributed environment. In this paper, a data sharing scheme based on blockchain, smart contract and attribute-based encryption is proposed, which supports attribute level user authority revocation, and is suitable for the privilege management of data sharing in distributed environment. Firstly, the model of data sharing and exchange is given; secondly, the operation of data sharing and exchange is defined; finally, implementation by smart contract is given and an experiment is carried out. The results show that the scheme can effectively solve the problem of data access authorization and revocation in distributed environment. In this scheme, we introduce the trusted third party as the key management center to generate, encrypt and decrypt the key, thus reducing the pressure on the client.