Research On The Key Issues Of Resource Access Control Under Distributed Environments

Resources access control (AC) is an essential defensive measure against a large number of security attacks. Under distributed environment, use of middleware technology is one common method to support access control, but it also incurs some problems to be overcome for the method to be fully effective. 1) It does not offer a complete solution, as application developers often have to resort to embedding AC into application code components. As a result, AC functionality is intertwined with application logic, making implementation difficult and inefficient with high error rates and unclear ownerships of resources. 2) For security protection to be effective in many application areas, AC requires fine granularity of control, use of application specific information in authentication and in granting resource access, and enhancement of authentication uniformity and reliability among multiple different organizations. 3) Middleware components are increasingly heterogeneous in structure and complicated for inter-component communication. When middleware components are used, one must be aware of their security characteristics. For example, one must know if there is danger of data leak in the network. However, it is difficult to prove if middleware components have good security functions.In order to improve on the completeness and effectiveness of middleware access control, this thesis proposes a new architectural method: J2EE based RBAC support. First, we analyze in detail the workings and performance of J2EE access control mechanism. We then provide a design on the J2EE protection system configuration that allows formal definition of system states. The thesis proposes a design of an authentication algorithm in terms of such definition. Second, this thesis studies how to support Role Based Access Control model when providing J2EE security service. Using J2EE protection system configuration, we give a definition of RBAC₀ å’Œ RBAC₁ in J2EE language. We also give a description and analysis of necessary conditions for implementing J2EE security service to support RBAC₀-RBAC_3s models. Our proposed methods provide RBAC₀ support while conforming to the J2EE security requirements, and additional functionality beyond J2EE security requirements, in order to support RBAC₁ å’Œ RBAC₂. All of our work greatly enhances performance of J2EE Access Control mechanisms.The combination of RBAC model and J2EE middleware access control mechanism works well to solve the problem of incompleteness and ineffectiveness. However, in the case of complicated security strategies, the combination still has problems of low flexibility, coarse granularity, poor scalability, etc. This thesis work includes a design of an authentication service system structure (JCRADS), to solve various access control issues for distributed resources. JCRADS extracted the logic of authentication service, and places theauthentication service outside of application code, thus making it independent of security model and rules in the lower layers of an application system. This resource access control method solves many issues incurred in protecting distributed resources. It allows multiple types of security strategies for authentication, and its service structure allows use of information obtained from work flows and other resources. As such, the authentication service system can support special rules in different specific application areas, as well as utilization of specific information for authentication. Wrapped up as an independent service, the authentication logic can easily maintain access control strategy consistency when it works across different application boundaries. In addition, this structure allows multiple authentication models and can assist security administrators and application developers in clearly separating their responsibilities.Although our design makes use of security mechanisms used by J2EE, JCRADS is almost independent of lower level security techniques. JCRADS can be used in many different distributed environments. The structure not only simplifies application and security system development, but also enables an administration staff to consistently manage and enforce its security strategies, therefore solving problems of low flexibility, coarse granularity and poor scalability that often exist in distributed resource access control systems.For deploying JCRADS on the Nationality Science and Technology Basic Platform(II]siC ^ffeSSfttjIM^^Po1), the thesis work includes an implementation of a test-bed based on JAS of JCRADS. This implementation has the properties of agile, flexible, extensible and portable authentication service structure, and plays the role of a test bed for JCRADS performance in actual systems. With JAS affiliated to JCRADS service, the implementation provides a framework to study the JCRADS method.One of the major works of this thesis is to study wrapper method for unsecured middleware components. This wrapper method allows middleware components to be executed in a secured environment. Wrappers are used to provide fine granularity control between middleware components and between such components and system resources. Several wrappers are implemented and described by using box-calculus: filter wrapper, logging wrapper, pipeline wrapper and n-element wrapper. The thesis provides a discussion on how security can be ensured by the use of such wrappers of various types.