Security analysis in role-based access control

Abstract

The administration of large role-based access control (RBAC) systems is a challenging problem. In order to administer such systems, decentralization of administration tasks by the use of delegation is an effective approach. While the use of delegation greatly enhances flexibility and scalability, it may reduce the control that an organization has over its resources, thereby diminishing a major advantage RBAC has over discretionary access control (DAC). We propose to use security analysis techniques to maintain desirable security properties while delegating administrative privileges. We give a precise definition of a family of security analysis problems in RBAC, which is more general than safety analysis that is studied in the literature. We show that two classes of problems in the family can be reduced to similar analysis in the RT[↞∩] role-based trust-management language, thereby establishing an interesting relationship between RBAC and the RT framework. The reduction gives efficient algorithms for answering most kinds of queries in these two classes and establishes the complexity bounds for the intractable cases.