Specified keywords search scheme for EHR sharing

Searchable encryption allows data users to search for encrypted files by keywords without restriction. However, electronic health record (EHR) contains sensitive information, and data users should search for and share EHR with restriction. If data users are not restricted when EHR is searched and shared, there is a high risk that EHR will be misused and reveal large amounts of private patient information. This paper proposes a specified keywords search scheme for EHR sharing based on searchable encryption and proxy re-encryption to address this problem. In the scheme, the data user searches with the keywords specified by the doctor and obtains EHR from the medical cloud. Proxy re-encryption is used to implement the sharing of EHR and privacy preservation securely. The security proof demonstrates that our scheme is secure against chosen keyword attack. Furthermore, the experimental results show that the scheme achieves computational efficiency.