Smart Contract-Based Access Control Through Off-Chain Signature and On-Chain Evaluation

Access control is essential in computer security systems to regulate the access to critical or valuable resources. Conventional access control models mainly rely on a centralized and trusted server to mediate each attempted access from client to resources, which face serious challenges of single point of failure and lack of transparency. In this brief, we propose a smart contract-based access control framework, which enables the owner to achieve resource access control in a reliable, auditable and scalable way. An access control contract is deployed on blockchain to manage attribute-based access policies of resources flexibly and make access decisions for clients credibly. A set of attributes is distributed to the clients through off-chain signatures signed by the owner to determine their privileges, without consuming the expensive on-chain storage space. Finally, we implement an experimental prototype on Ethereum test network and perform extensive experimental and theoretical analysis to evaluate its scalability and efficiency.