Security Patterns Template and Tutorial

1. Security Patterns Template and Tutorial - Darrell M. Kienzle, Ph.D., Matthew C. Elder, Ph.D., David S. Tyree, James Edwards-Hewitt Presented by Dan Frohlich

2. Overview • What is a Pattern? • What is a Security Pattern? • The Security Pattern Template. • Related Work.

3. What is a Pattern? • Developed by Christopher Alexander for Architectural and Urban Planning • Made popular for software design by GoF. • Definition: A solution to a problem in a context. • Summary, solution and impact • Expanded to include recurrence, a teaching component, and a name by J. Vlissides (GoF)

4. Variations • Architectural patterns. • Enterprise Level (System Patterns) • AntiPatterns. • Document common mistakes • Pattern Languages. • Families of solutions good for OO Frameworks.

5. What is a Security Pattern? • Technique for encapsulating and disseminating security expertise. • Some but not all are design Patterns • Structural Security Patterns • Like GoF Design Patterns • Procedural Security Patterns • Improve the development process of secure software

6. Audience drives Level of Detail • Concepts • General Strategies like “Least Privilege” • Classes of Patterns • General problem area with many solutions • Patterns • General enough to be used in many circumstances • Examples • A worked solution for a specific problem instance

7. The Security Pattern Template. • Pattern Name • Noun describing a thing to be built. (Structural) • Verb describing recommended action. (Procedural) • Abstract • Describes intent/purpose • Independent of context • Indicates limits on applicability.

8. The Security Pattern Template. • Aliases • Also Known As • Problem • Context for application • Motivation for use • Solution • Applicability / Rationale • How the Pattern solves the Problem

9. The Security Pattern Template. • Static Structure • Includes a Diagram if applicable or a note if not • Enumerates the components of the Diagram • Dynamic Structure • Collaborations • Outlines Component interactions

10. The Security Pattern Template. • Implementation Issues • Detailed hints and techniques • Identify pitfalls, and guide reader around them • Common attacks • Identify attacks that interact with this pattern • Links to public databases

11. The Security Pattern Template. • Known Uses • Cite examples of this pattern from all 3 levels when possible. • Code Level • Rely on language features. • System Level • Rely on OS features • Network Level • Implemented with network level components.

12. The Security Pattern Template. • Sample Code • Presented whenever possible. • Adds tangibility to an abstract idea. • Consequences • Each area should be discussed. • Accountability, Confidentiality, Integrity, Availability, Performance, Cost, Manageability, Usability

13. The Security Pattern Template. • Related Patterns • Reference related patterns and the nature of the relationship • References • Enumerate citations related to the pattern

14. Related Work • Security Properties of Design Patterns • Security ramifications of GoF • NRL Patterns work • Formal verification of security-critical software • www.security-patterns.de • Collaborative site for security pattern developers

15. Related Work (cont.) • OpenGroup Security Forum • Developing a library of architectural security patterns.

16. Questions