Security Analysis of Role-based Access Control through Program Verification

We propose a novel scheme for proving administrative role-based access control (ARBAC) policies correct with respect to security properties using the powerful abstraction based tools available for program verification. Our scheme uses a combination of abstraction and reduction to program verification to perform security analysis. We convert ARBAC policies to imperative programs that simulate the policy abstractly, and then utilize further abstract-interpretation techniques from program analysis to analyze the programs in order to prove the policies secure. We argue that the aggressive set-abstractions and numerical-abstractions we use are natural and appropriate in the access control setting. We implement our scheme using a tool called VAC that translates ARBAC policies to imperative programs followed by an interval-based static analysis of the program, and show that we can effectively prove access control policies correct. The salient feature of our approach are the abstraction schemes we develop and the reduction of role-based access control security (which has nothing to do with programs) to program verification problems

Governance of Marine Protected Areas in Developing Countries : an Analysis Framework. Evidence from Thailand.

International audienceThe main aim of this paper is the design of an analysis framework for the governance of MPAs in developing countries. The working-out of this analysis framework makes use of contributions from the governance of hazardous activities, the interactive fisheries governance, the ecosystem-based management applied to marine protected areas, the MPAs governance indicators, the anthropology of brokerage. This analysis framework takes in count four main issues of the MPAs governance in developing countries pointed out from two representative case studies (Mu Ko Chumphon National Park in Thailand and Ca Mau National Park in Vietnam) : the revitalization of regulatory systems of the access to fisheries resources, the simplification of the administrative processes, the control of the demographic pressure which result from a high increase of the populations and a strong mobility, the lowering of the economic vulnerability and poverty alleviation due to the deregulation. This analysis framework makes it possible to characterize the governance systems and to put forward the weaknesses : the excessive role play by the international organizations, the too sectorial and technical aspect of fisheries management measures, the incomplete decentralization, the fragmentation of the States and the civil society. To mitigate these deficiencies, four general public policy options adapted to developing countries are proposed

Policy analysis for self-administrated role-based access control

Current techniques for security analysis of administrative role-based access control (ARBAC) policies restrict themselves to the separate administration assumption that essentially separates administrative roles from regular ones. The naive algorithm of tracking all users is all that is known for the security analysis of ARBAC policies without separate administration, and the state space explosion that this results in precludes building effective tools. In contrast, the separate administration assumption greatly simplifies the analysis since it makes it sufficient to track only one user at a time. However, separation limits the expressiveness of the models and restricts modeling distributed administrative control. In this paper, we undertake a fundamental study of analysis of ARBAC policies without the separate administration restriction, and show that analysis algorithms can be built that track only a bounded number of users, where the bound depends only on the number of administrative roles in the system. Using this fundamental insight paves the way for us to design an involved heuristic to further tame the state space explosion in practical systems. Our results are also very effective when applied on policies designed under the separate administration restriction. We implement our techniques and report on experiments conducted on several realistic case studies

Refinement for Administrative Policies

Flexibility of management is an important requisite for access control systems as it allows users to adapt the access control system in accordance with practical requirements. This paper builds on earlier work where we defined administrative policies for a general class of RBAC models. We present a formal definition of administrative refinnement and we show that there is an ordering for administrative privileges which yields administrative refinements of policies. We argue (by giving an example) that this privilege ordering can be very useful in practice, and we prove that the privilege ordering is tractable

Analyzing temporal role based access control models

Today, Role Based Access Control (RBAC) is the de facto model used for advanced access control, and is widely deployed in diverse enterprises of all sizes. Several extensions to the authorization as well as the administrative models for RBAC have been adopted in recent years. In this paper, we consider the temporal extension of RBAC (TRBAC), and develop safety analysis techniques for it. Safety analysis is essential for understanding the implications of security policies both at the stage of specification and modification. Towards this end, in this paper, we first define an administrative model for TRBAC. Our strategy for performing safety analysis is to appropriately decompose the TRBAC analysis problem into multiple subproblems similar to RBAC. Along with making the analysis simpler, this enables us to leverage and adapt existing analysis techniques developed for traditional RBAC. We have adapted and experimented with employing two state of the art analysis approaches developed for RBAC as well as tools developed for software testing. Our results show that our approach is both feasible and flexible

ARBAC Policy for a Large Multi-National Bank

Administrative role-based access control (ARBAC) is the first comprehensive administrative model proposed for role-based access control (RBAC). ARBAC has several features for designing highly expressive policies, but current work has not highlighted the utility of these expressive policies. In this report, we present a case study of designing an ARBAC policy for a bank comprising 18 branches. Using this case study we provide an assessment about the features of ARBAC that are likely to be used in realistic policies

The Role of Civil Society in Decentralisa-tion and Alleviating Poverty: An Exploratory Case Study from Tanzania

This research report gauges Tanzanian civil society's influence in setting the decentralisation agenda, in providing crucial basic services (e.g. health) or to which extent CSOs advocate the rural poor about their rights and obligations