34,161 research outputs found
A Declarative Framework for Specifying and Enforcing Purpose-aware Policies
Purpose is crucial for privacy protection as it makes users confident that
their personal data are processed as intended. Available proposals for the
specification and enforcement of purpose-aware policies are unsatisfactory for
their ambiguous semantics of purposes and/or lack of support to the run-time
enforcement of policies.
In this paper, we propose a declarative framework based on a first-order
temporal logic that allows us to give a precise semantics to purpose-aware
policies and to reuse algorithms for the design of a run-time monitor enforcing
purpose-aware policies. We also show the complexity of the generation and use
of the monitor which, to the best of our knowledge, is the first such a result
in literature on purpose-aware policies.Comment: Extended version of the paper accepted at the 11th International
Workshop on Security and Trust Management (STM 2015
Policy based roles for distributed systems security
Distributed systems are increasingly being used in commercial environments necessitating the development of trustworthy and reliable security mechanisms. There is often no clear informal or formal specification of enterprise authorisation policies and no tools to translate policy specifications to access control implementation mechanisms such as capabilities or Access Control Lists. It is thus difficult to analyse the policy to detect conflicts or flaws and it is difficult to verify that the implementation corresponds to the policy specification. We present in this paper a framework for the specification of management policies. We are concerned with two types of policies: obligations which specify what activities a manager or agent must or must not perform on a set of target objects and authorisations which specify what activities a subject (manager or agent) can or can not perform on the set of target objects. Management policies are then grouped into roles reflecting the organisation..
Using Event Calculus to Formalise Policy Specification and Analysis
As the interest in using policy-based approaches for systems management grows, it is becoming increasingly important to develop methods for performing analysis and refinement of policy specifications. Although this is an area that researchers have devoted some attention to, none of the proposed solutions address the issues of analysing specifications that combine authorisation and management policies; analysing policy specifications that contain constraints on the applicability of the policies; and performing a priori analysis of the specification that will both detect the presence of inconsistencies and explain the situations in which the conflict will occur. We present a method for transforming both policy and system behaviour specifications into a formal notation that is based on event calculus. Additionally it describes how this formalism can be used in conjunction with abductive reasoning techniques to perform a priori analysis of policy specifications for the various conflict types identified in the literature. Finally, it presents some initial thoughts on how this notation and analysis technique could be used to perform policy refinement
Security Policy Specification Using a Graphical Approach
A security policy states the acceptable actions of an information system, as
the actions bear on security. There is a pressing need for organizations to
declare their security policies, even informal statements would be better than
the current practice. But, formal policy statements are preferable to support
(1) reasoning about policies, e.g., for consistency and completeness, (2)
automated enforcement of the policy, e.g., using wrappers around legacy systems
or after the fact with an intrusion detection system, and (3) other formal
manipulation of policies, e.g., the composition of policies. We present LaSCO,
the Language for Security Constraints on Objects, in which a policy consists of
two parts: the domain (assumptions about the system) and the requirement (what
is allowed assuming the domain is satisfied). Thus policies defined in LaSCO
have the appearance of conditional access control statements. LaSCO policies
are specified as expressions in logic and as directed graphs, giving a visual
view of policy. LaSCO has a simple semantics in first order logic (which we
provide), thus permitting policies we write, even for complex policies, to be
very perspicuous. LaSCO has syntax to express many of the situations we have
found to be useful on policies or, more interesting, the composition of
policies. LaSCO has an object-oriented structure, permitting it to be useful to
describe policies on the objects and methods of an application written in an
object-oriented language, in addition to the traditional policies on operating
system objects. A LaSCO specification can be automatically translated into
executable code that checks an invocation of a program with respect to a
policy. The implementation of LaSCO is in Java, and generates wrappers to check
Java programs with respect to a policy.Comment: 28 pages, 22 figures, in color (but color is not essential for
viewing); UC Davis CS department technical report (July 22, 1998
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