LSE: Efficient Symmetric Searchable Encryption based on Labeled PSI

Searchable encryption (SE) allows a data owner to outsource encrypted documents to an untrusted cloud server while preserving privacy and achieving secure data sharing. However, most existing SE schemes have a trade-off between security and efficiency. Moreover, these SE schemes leak the server's partial database or search information to perform better. Recent attacks show that such leakages can be used to recover the content of queried keywords or partial database information. To solve this problem and ensure efficiency, this paper proposes labeled searchable encryption (LSE), an efficient searchable encryption scheme based on the labeled private set intersection. We also give formal proofs to prove the security of the proposed labeled PSI protocol and searchable encryption scheme. Finally, we do experiments to compare the performance with some state-of-the-art works, and the experimental results show that the LSE outperforms in terms of total size and generation time of the encrypted database as well as the total search time at client side.