@conference {14679,
	title = {Dynamic Enforcement of Knowledge-Based Security Policies},
	booktitle = {Computer Security Foundations Symposium (CSF), 2011 IEEE 24th},
	year = {2011},
	month = {2011/06/27/29},
	pages = {114 - 128},
	publisher = {IEEE},
	organization = {IEEE},
	abstract = {This paper explores the idea of knowledge-based security policies, which are used to decide whether to answer queries over secret data based on an estimation of the querier{\textquoteright}s (possibly increased) knowledge given the results. Limiting knowledge is the goal of existing information release policies that employ mechanisms such as noising, anonymization, and redaction. Knowledge-based policies are more general: they increase flexibility by not fixing the means to restrict information flow. We enforce a knowledge-based policy by explicitly tracking a model of a querier{\textquoteright}s belief about secret data, represented as a probability distribution, and denying any query that could increase knowledge above a given threshold. We implement query analysis and belief tracking via abstract interpretation using a novel probabilistic polyhedral domain, whose design permits trading off precision with performance while ensuring estimates of a querier{\textquoteright}s knowledge are sound. Experiments with our implementation show that several useful queries can be handled efficiently, and performance scales far better than would more standard implementations of probabilistic computation based on sampling.},
	keywords = {abstract interpretation, belief networks, belief tracking, Data models, dynamic enforcement, Facebook, information flow, knowledge based systems, knowledge-based security, knowledge-based security policy, privacy, probabilistic computation, probabilistic logic, probabilistic polyhedral domain, probabilistic polyhedron, probability, query analysis, Security, security of data, semantics, Waste materials},
	isbn = {978-1-61284-644-6},
	doi = {10.1109/CSF.2011.15},
	author = {Mardziel,P. and Magill,S. and Hicks, Michael W. and Srivatsa,M.}
}
@conference {14696,
	title = {Fable: A Language for Enforcing User-defined Security Policies},
	booktitle = {IEEE Symposium on Security and Privacy, 2008. SP 2008},
	year = {2008},
	month = {2008/05/18/22},
	pages = {369 - 383},
	publisher = {IEEE},
	organization = {IEEE},
	abstract = {This paper presents FABLE, a core formalism for a programming language in which programmers may specify security policies and reason that these policies are properly enforced. In FABLE, security policies can be expressed by associating security labels with the data or actions they protect. Programmers define the semantics of labels in a separate part of the program called the enforcement policy. FABLE prevents a policy from being circumvented by allowing labeled terms to be manipulated only within the enforcement policy; application code must treat labeled values abstractly. Together, these features facilitate straightforward proofs that programs implementing a particular policy achieve their high-level security goals. FABLE is flexible enough to implement a wide variety of security policies, including access control, information flow, provenance, and security automata. We have implemented FABLE as part of the LINKS web programming language; we call the resulting language SELlNKS. We report on our experience using SELlNKS to build two substantial applications, a wiki and an on-line store, equipped with a combination of access control and provenance policies. To our knowledge, no existing framework enables the enforcement of such a wide variety of security policies with an equally high level of assurance.},
	keywords = {Access control, Automata, Collaborative work, Communication system security, Computer languages, computer security, Data security, enforcement policy, FABLE, Government, high-level security goals, information flow, Information security, Language-based security, programming languages, Programming profession, provenance, security automata, security labels, security of data, user-defined security policies, verified enforcement, Web programming language},
	isbn = {978-0-7695-3168-7},
	doi = {10.1109/SP.2008.29},
	author = {Swamy,N. and Corcoran,B.J. and Hicks, Michael W.}
}
