Abstract:

The scheme of encrypted database based on trusted execution environment has significant performance advantages compared with other schemes, but it faces security challenges in the design of index structure. The existing schemes will leak data sequence information and there is a threat of abuse of decryption interface. To address the above problems, this paper proposed a security-enhanced index scheme in encrypted database based on trusted execution environment. The scheme accelerated equivalent and range queries by using an index structure based on dynamic searchable symmetric encryption to ensure that the index structure leakage was controllable. In addition, this paper designed a verification mechanism for embedded indexes to prevent malicious attackers from obtaining the plaintext information of sensitive data through arbitrary called to the interface. This paper conducted a security analysis, which proved that the scheme in this paper effectively prevented malicious arbitrary call attacks while protecting data privacy. This paper conducted performance tests in the Intel SGX environment, and the results show that the index in this paper significantly improves the query efficiency compared to the no-index scheme. Compared with the leaked index scheme, the efficiency is flat, and it is also feasible in indicators such as update efficiency, verification mechanism lightweight, and trusted area processing data volume.

Key words: trusted execution environment, encrypted database, secure index, searchable symmetric encryption