Fair searchable encryption method and fair searchable encryption system

The invention relates to a fair searchable encryption method and a fair searchable encryption system, the fair searchable encryption method combines a national cryptographic algorithm and a symmetric searchable encryption technology, for a big data scene in a cloud environment, the symmetric searchable encryption technology with higher encryption and decryption efficiency is used, encryption and decryption are realized by using a national cryptographic SM4 grouping algorithm, the encryption and decryption efficiency of the data set is improved, a traditional searchable encryption algorithm is optimized, and the retrieval efficiency is improved to a certain extent. Moreover, a plurality of contract functions are designed in combination with the characteristic that the intelligent contract in the block chain allows to automatically execute the contract content without a third party, so that a fairness protocol is provided, the problem of unfairness of the transaction between the user and the cloud server in the