| With the improvement of blockchain infrastructure,more and more industries have put their services on the chain,forming a prosperous blockchain service ecology,but at the same time,it brings the problem of data silos:the businesses of different enterprises are in different blockchains,isolating each other and causing inconvenience to data sharing and circulation.The business of different enterprises are isolated from each other,causing inconvenience to data sharing and circulation.As a necessary means of information flow between systems,many researchers have combined traditional access control schemes with blockchain technology to achieve a good decentralised and auditable access control mechanism.However,the existing blockchain-based access control schemes cannot well balance the complex access control requirements with the generality of access control policies,and lack attention to the problem of large storage space occupation for access control policies.There have been attribute-based access control schemes that store user attributes on the blockchain and implement information collection for access control based on the nature of shared information in the blockchain.Directly applying these schemes to cross-chain scenarios,there is the problem of interbusiness user attribute privacy leakage.This paper addresses the abovementioned problems and conducts relevant research with the objectives of reducing the storage space of policies in the process of solving cross-chain access control,improving the generality of policies and protecting the privacy of user attributes in the process of cross-chain,and achieves the following results.To address the problems of poor generality and large space consumption of cross-chain access control policies,a storage efficient access control policy HES and an algorithm for parsing and converting from XACML policies are designed using XACML standard policies and attribute-based access control mechanisms,realising a cross-chain access control scheme with high storage efficiency,fine granularity and good generality.To address the problem of attribute privacy leakage during cross-chain access control,a homomorphic hash search tree based privacy protection algorithm is proposed,and a "generation-verification process" is designed to achieve correct policy verification without compromising user privacy,while It supports fast renewal and revocation of attribute authorisation.The cross-chain access control system HF-Controller is implemented based on the Fabric federated chain.The system has the advantages of good generality,small policy size,high execution efficiency and support for user number attribute privacy protection compared with other solutions. |
