Types for Role-Based Access Control of Dynamic Web Data

We introduce a role-based access control calculus for modelling dynamic web data and a corresponding type system. It is an extension of the Xdπ calculus proposed by Gardner and Maffeis. In our framework, a network is a parallel composition of locations, where each location contains processes with roles and a data tree whose edges are associated with roles. Processes can communicate, migrate from a location to another, use the data, change the data and the roles in the local tree. In this way, we obtain a model that controls process access to data. We propose a type system which ensures that a specified network policy is respected during computations. Finally, we show that our calculus obeys the following security properties: (1) all data trees and processes with roles in a location agree with the location policy; (2) a process can migrate only to a location with whose policy it agrees; (3) a process with roles can read and modify only data which are accessible to it; (4) a process with roles can enable and disable roles in agreement with the location policy.