System for decentralized identification of file access permission

A system for decentralized identification of a file access permission, comprising:

• a front-end program, comprising at least one credential, wherein the at least one credential comprises a definition file identifier (ID) and at least one piece of attribute data;
• and
• an access control server, communicatively connected to a file system and a blockchain, wherein the file system stores at least one file, and the access control server comprises:
• a storage module, storing at least one condition setting file, wherein the condition setting file records at least one access condition, and each of the files corresponds to one of the at least one access condition;
• a network interface, configured to receive an access request that is transmitted by the front-end program and corresponds to a specified file of the at least one file;
• and
• a processor, coupled to the storage module and the network interface, and in response to the access request, obtaining the access condition corresponding to the specified file from the at least one condition setting file, and transmitting a check rule message comprising the access condition to the front-end program through the network interface, wherein
• the front-end program is configured for extracting the at least one piece of attribute data and the definition file ID corresponding to the access condition from the at least one credential based on the check rule message, to form a multi-credential proof file, and returning the multi-credential proof file to the access control server;
• and
• the access control server is configured to receive the multi-credential proof file through the network interface, and the processor is configured to query the blockchain for a credential definition file and a first public key corresponding to each of the definition file IDs in the multi-credential proof file through the network interface, so as to confirm, based on each obtained credential definition file and each obtained first public key, that each piece of the attribute data in the multi-credential proof file is correct, confirm that all of the attribute data in the multi-credential proof file meets the access condition, and then grant the front-end program an access permission corresponding to the specified file.