Logic-based reasoning on delegatable authorizations

![CDATA[In this paper, we propose a logic program based formulation that supports delegatable authorizations, where negation as failure, classical negation and rules inheritance are allowable. A conflict resolution policy has been developed in our approach that can be used to support the controlled delegation and exception. In our framework, authorization rules are specified in a Delegatable Authorization Program (DAP) which is an extended logic program associated with different types of partial orderings on the domain, and these orderings specify various inheritance relationships among subjects, objects and access rights in the domain. The semantics of a DAP is defined based on the well-known stable model and the conflict resolution is achieved in the process of model generation for the underlying DAP. Our framework provides users a feasible way to express complex security policies.]]