Treffer: Safety and Consistency Verification for a High-level Permission Assignment Constraint

Existing permission assignment constraints pay more attention to ensure the safety,however the availability for the system is ignored.Aiming at this problem,this paper proposes a High-level Permission Assignment (HPA)constraint to satisfy the safety and availability requirements simultaneously.It defines the safety verification problem and consistency verification problem,which determine whether an access control state can satisfy a HPA constraint,and whether there exists a valid access control state to satisfy a set of high-level permission assignment constraints.The computing complexities of the safety verification problem and the consistency verification problem show that computing complexities of these two problems are NP-complete and NPNP.It also designs an optimized algorithm for the consistency checking problem by incorporating preprocessing and reducing to Satisfiability(SAT) problem solver.Simulation experimental results verify the effectiveness of the proposed algorithm.