To solve the problems of coarse-grained access control in blockchain data sharing,a blockchain data access control method based on attribute revocation ciphertext policy attribute based encryption was proposed.Based on the existing scheme,the pre decryption process was introduced.Combined with the attribute revocation list,the real-time revocation of the attribute was realized.The security was proved based on the assumption of decisional bilinear Diffie-Hellman problem under asymmetric group.The system was designed based on the Hyperledger Fabric.Combined with the interstellar file system,the on chain and off chain storage method was adopted to solve the problems of insufficient capacity and system efficiency of the blockchain.The experimental result shows that the proposed scheme does not require updating the key ciphertext and repeatedly storing in the blockchain when revoking attributes.And,the proposed scheme only needs 6 Pairing operations for pre decryption and decryp-tion.In addition,under the large-scale attribute set,the pre decryption time and decryption time are kept at a constant level of about 100 milliseconds on average,which ensures the efficient operation of the blockchain system and realizes the fine-grained access control of blockchain data.
关键词
区块链/数据共享/访问控制/属性基加密/预解密/属性撤销/星际文件系统
Key words
blockchain/data sharing/access control/attribute based encryption/pre decryption/attribute revocation/interstel-lar file system
维普
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