Searchable Proxy Re-Encryption Data Sharing Scheme Based on Consortium Chain

In order to solve the problems of low data retrieval efficiency, lack of flexible authority management, and difficulty in meeting the needs of multi-user massive data sharing in data sharing scenarios, a searchable proxy re-encryption data sharing scheme based on alliance chains is proposed, which realizes the dynamics of cloud data sharing process Fine-grained access control and efficient retrieval of ciphertext keywords. In this scheme: the original data is encrypted using the AES algorithm, the symmetric key and the keyword are respectively encrypted using a non-interactive proxy re-encryption algorithm and a searchable encryption algorithm; the original data ciphertext is stored in the Interplanetary File System (IPFS), and the keyword Metadata such as ciphertext and permission control policies are stored on the alliance chain. Use smart contracts to realize decentralized ciphertext conversion, combined with the advantages of B+ tree index, to achieve efficient search of ciphertext keywords and quick verification of permissions. Designing a non-interactive proxy re-encryption algorithm can generate proxy keys quickly and efficiently, and is suitable for multi-user complex data sharing scenarios. The solution also supports dynamic management of access rights to meet data sharing requirements in different scenarios. The experimental analysis results show that the keyword matching algorithm takes an average of 1lms, which exhibits higher efficiency compared to the global keyword search scheme. In the concurrent access test experiment, the maximum throughput of the system is 24 transactions per second, and the transaction success rate is high. Therefore, the system has a good concurrent access capability to meet the practical use.