Departmental Papers (CIS)

Document Type

Journal Article

Subject Area

CPS Formal Methods

Date of this Version



Suggested Citation:
Nikhil Dinesh, Aravind Joshi, Insup Lee, and Oleg Sokolsky. (2011). "Permission to speak: A logic for access control and conformance." Journal of Logic and Algebraic Programming. Vol. 80(1), p. 50-74.


Formal languages for policy have been developed for access control and conformance checking. In this paper, we describe a formalism that combines features that have been developed for each application. From access control, we adopt the use of a saying operator. From conformance checking, we adopt the use of operators for obligation and permission. The operators are combined using an axiom that permits a principal to speak on behalf of another. The combination yields benefits to both applications. For access control, we overcome the problematic interaction between hand-off and classical reasoning. For conformance, we obtain a characterization of legal power by nesting saying with obligation and permission.

The axioms result in a decidable logic. We integrate the axioms into a logic programming approach, which lets us use quantification in policies while preserving decidability of access control decisions. Conformance checking, in the presence of nested obligations and permissions, is shown to be decidable. Non-interference is characterized using reachability via permitted statements.


Access control; Conformance; Modal logic; Deontic logic


Date Posted: 01 February 2011

This document has been peer reviewed.