Reflective Database Access Control

Olson, Lars E.

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https://hdl.handle.net/2142/13853 Copy

Description

Title

Reflective Database Access Control

Author(s)

Olson, Lars E.

Issue Date

2009-10-01

Director of Research (if dissertation) or Advisor (if thesis)

Gunter, Carl A.

Doctoral Committee Chair(s)

• Gunter, Carl A.
• Winslett, Marianne

Committee Member(s)

• Parthasarathy, Madhusudan
• Cook, William R.

Department of Study

Computer Science

Discipline

Computer Science

Degree Granting Institution

University of Illinois at Urbana-Champaign

Degree Name

Ph.D.

Degree Level

Dissertation

Keyword(s)

• Access Control
• Database Systems
• Formal Security Analysis

Language

en

Abstract

Reflective Database Access Control (RDBAC) is a model in which a database privilege is expressed as a database query itself, rather than as a static privilege contained in an access control list. RDBAC aids the management of database access controls by improving the expressiveness of policies. However, such policies introduce new interactions between data managed by different users, and can lead to unexpected results if not carefully written and analyzed. We propose the use of Transaction Datalog syntax and semantics as a formal framework for expressing reflective access control policies. Using a formal logic-based language provides a basis for analyzing policies and enables secure implementations that can guarantee that certain configurations built on these policies cannot be subverted. We demonstrate this by defining two classes of policy configurations, and proving that under any set of such policies, a decidable algorithm can determine whether or not access to a sensitive data item can ever be leaked to an unprivileged user. Although the Transaction Datalog language provides a powerful syntax and semantics for expressing RDBAC policies, there is no efficient implementation of this language for practical database systems. We demonstrate a strategy for compiling policies into standard SQL views that enforce the policies, including overcoming significant differences in semantics between the languages in handling side-effects and evaluation order. We also report the results of evaluating the performance of these views compared to policies enforced by traditional access control lists, using a common off-the-shelf relational database management system. We also present two case studies for systems that can be protected using RDBAC security policies. These case studies demonstrate the flexibility of the system by implementing a wide range of functionality, as well as the practicality and scalability of using such a system in real-world applications that require non-trivial policy definitions on large data sets. This work establishes the theoretical soundness of using RDBAC as a basis for access control. It describes an efficient translation process for executing a useful subset of RDBAC rules in standard SQL, thereby demonstrating its practical feasibility using existing software. We show how RDBAC can be applied to realistic applications. These results suggest a rich field of further research.

Sponsor(s)/Grant Number(s)

• NSF CNS 07-16626
• NSF CNS 07-16421
• NSF CNS 05-24695
• ONR N00014-08-1-0248
• NSF CNS 05-24516
• DHS 2006-CS-001-000001
• MacAruthur Foundation
• Boeing Corporation

Type of Resource

text

Permalink

http://hdl.handle.net/2142/13853

Copyright and License Information

Copyright 2009 by LARS E. OLSON. All rights reserved.

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