A Declarative Fine-grained Role-based Access Control Model and Mechanism for the Web Application Domain

Abstract

Access control policies such as role-based access control (RBAC) enforce desirable security properties, in particular for Web-based applications with many different users. A fine-grained RBAC model gives the developers of such systems more customization and administrative power to control access to fine-granular elements such as individual cells of a table. However, the definition and deployment of such policies is not straightforward, and in many Web applications, they are hand-coded in the database or scattered throughout the application's implementation, without taking advantage of underlying central elements, such as the data model or object types. This paper presents ΦRBAC, a fine-grained RBAC model for the Web application domain. ΦRBAC achieves separation of concerns for enforcing access to a range of objects with mixed-granularity levels. Moreover, it provides a unique testing mechanism that gives a guarantee to the developer about the correctness, completeness, and sufficiency of the defined ΦRBAC model, both internally and in the context of its target application. We use code generation techniques to compile the specification of a ΦRBAC model down to the existing tiers of an existing domain-specific Web programming language, WebDSL. We show the benefits of ΦRBAC on the development of a departmental Web site.