Research On Attribute-Based Searchable Encryption Scheme For Shared Multi-Data Owner

The combination of the Internet of Things and cloud storage has brought a revolutionary change to data management,and more and more enterprises and users are choosing to store their data in the cloud.Although the cloud-assisted Io T architecture can provide highly available computing and massive storage services,the semi-trusted nature of cloud servers may lead to data leakage and abuse.To ensure the confidentiality and security of data,encryption is usually performed before uploading data to the cloud.However,this also brings many challenges to the sharing and retrieval of encrypted data.Attribute-based searchable encryption mechanism combines attribute-based encryption and searchable encryption to achieve effective retrieval of encrypted keywords and fine-grained access control.Currently,most attribute-based searchable schemes are only applicable to scenarios with a single data owner,and directly applying them to environments involving multiple data owners,such as the Internet of Things,will bring complex key management issues.Therefore,this paper focuses on the research of attribute-based searchable encryption schemes in the shared multi-data owner environment.The main contributions are as follows:(1)An attribute-based searchable encryption scheme that supports multiple data owners has been constructed.The scheme designs a novel master key generation and private key aggregation mechanism,enabling all data owners to use their own master key in a privacy-preserving manner and to jointly generate an aggregated private key for data users.In addition,users only need to maintain one private key and use a single trapdoor for each search,solving the complex key management problem in the multi-data owner model and greatly reducing communication and search costs.At the same time,a secure inverted index structure is constructed to improve the accuracy of returning files.Security analysis shows that the scheme achieves IND-s CP-CPA security and IND-CKA security.(2)A multi-keyword searchable attribute-based encryption scheme supporting ciphertext verifiability was constructed in a cloud-assisted Internet of Things environment.By utilizing the characteristics of blockchain such as immutability and transparency,smart contracts are designed to combine with the attribute-based searchable encryption technology to determine whether the keyword indexes and trapdoors match and to verify the completeness of the results returned by the cloud server.Connection keyword search is achieved through polynomial equations,which improves search accuracy and meets user needs.In addition,an outsourced cloud server is introduced to perform preliminary decryption and reduce computational expenses for the user.Finally,verify the correctness and perform security analysis of the solution,and demonstrate its practicality through performance analysis.