A multi-keyword searchable encryption sensitive data trusted sharing scheme in multi-user scenario

Searchable encryption technology provides a solution for the trusted sharing of sensitive data. A large amount of encrypted data stored in data sharing servers can support keyword search without exposing data privacy, which has attracted more and more scholars' attentions and researches. However, some multi-keyword searchable encryption schemes that deal with multi-semantic data still have security problems or low efficiency. To improve the security and efficiency of trusted sharing of sensitive data, we propose a multi-keyword searchable encryption scheme. The scheme designs a sensitive data sharing architecture based on blockchain technology, and the tamper-proof of distributed ledgers ensures the authenticity of encrypted data and indexes, as well as the supervision of sharing behaviors. On this basis, we improved the inverted index structure to achieve efficient multi-keyword searchable encryption while avoiding keyword-pair result pattern leakage. Our proposed scheme has passed formal security analysis, and simulation results show that the multi-keyword searchable encryption scheme is efficient.