Mandatory Security Policies Research Articles

Analysis of formal models for ensuring data integrity and their applicability to databases

Information systems in general and databases in particular are vulnerable to accidental or malicious attacks aimed at compromising data integrity. Security is easier if you have a clear model that is the formal expression of security policy. The paper explores known security models related to data integrity, their applicability and significance for databases. The analysis of formal models for ensuring data integrity revealed that each of them, having certain advantages and disadvantages, has the right to use. The decisive factor in making a decision is an assessment of a specific situation, which will make it possible to make the right choice, including their complex application. In this regard, the paper notes that the Clark-Wilson model, the undoubted advantages of which are its simplicity and ease of joint use with other security models, is advisable to use as a set of practical recommendations for building an integrity assurance system in information systems. While stating the fact that traditional DBMSs support many of the mechanisms of the Clark-Wilson model, the article points out that implementations based on standard SQL require some compromise solutions. Analyzing the Biba model, the paper concludes about its relative simplicity and the use of a well-studied mathematical apparatus. It is noted that in practice, for the creation of secure information systems, as systems that ensure the confidentiality and data integrity, it is important to unite the Bell-LaPadula and Biba models. Moreover, this union should be on the basis of one common lattice, but with two security labels (confidentiality and integrity) with the opposite character of their definition. This is exactly the variant of combining the Bell-LaPadula and Biba models that is recommended for use in modern information systems and DBMSs, where a mandatory security policy is implemented.

Demo proposal

Simple is a web framework for Haskell. Simple came out of our work on Hails, a platform for secure web applications. For Hails, we needed a flexible web framework that uses no unsafe language features and can be used to build apps outside the IO monad. Unlike many mainstream web frameworks, Simple does not enforce a particular structure or paradigm. Instead, it simply provides a set of composable building blocks to help developers structure and organize their web applications. We've used Simple to build both traditional web applications as well as applications with explicit, strong safety and security guarantees. In the demonstration, we'll focus on the former -- introducing the framework and motivating it's utility for traditional web apps -- and show how we can leverage the LIO information flow control library to add mandatory security policies to apps.

The Caernarvon secure embedded operating system

The Caernarvon operating system was developed to demonstrate that a high assurance system for smart cards was technically feasible and commercially viable. The entire system has been designed to be evaluated under the Common Criteria at EAL7, the highest defined level of assurance. Historically, smart card processors have not supported the hardware protection features necessary to separate the OS from the applications, and one application from another. The Caernarvon OS has taken advantage of the first smart card processors with such features to be the first smart card OS to provide this kind of protection. Even when compared with conventional systems where the hardware protection is routine, the Caernarvon OS is noteworthy, because of the EAL7 assurance. This approach facilitated implementation of a formally specified, mandatory security policy providing multi-level security (MLS) suitable for both government agencies and commercial users. The mandatory security policy requires effective authentication of its users that is independent of applications. For this reason, the Caernarvon OS also contains a privacy-preserving, two-way authentication protocol integrated with the Mandatory Security Policy. The Caernarvon OS includes a strong cryptographic library that has been separately certified under the Common Criteria at EAL5+ for use with other systems. The Caernarvon OS implements a secure method for downloading trusted and untrusted application software and data in the field, with the assumption that all applications are potentially hostile. While the initial platform for the operating system was smart cards, the design could also be used in other embedded devices, such as USB tokens, PDAs, cell phones, etc.

Mandatory security and object‐oriented systems: A multilevel entity model and its mapping onto a single‐level object model

The application of mandatory security policies in object-oriented systems require objects to be single-level, i.e., all information in an object must have the same security classification. However, real-world entities are often multilevel. Moreover, different coexistence options for property values at different levels are needed. In this paper we present a model for specifying multilevel entities. The proposed entity model supports different options by which users can specify whether low level values of entity properties are to be considered valid at higher levels or whether they represent cover stories not valid at higher levels. We then illustrate how entities expressed in this model can be mapped onto single-level objects. We also present a methodology and algorithms to automatically perform such a mapping. © 1998 John Wiley & Sons, Inc.

Enhancing medical database security.

A methodology for the enhancement of database security in a hospital environment is presented in this paper which is based on both the discretionary and the mandatory database security policies. In this way the advantages of both approaches are combined to enhance medical database security. An appropriate classification of the different types of users according to their different needs and roles and a User Role Definition Hierarchy has been used. The experience obtained from the experimental implementation of the proposed methodology in a major general hospital is briefly discussed. The implementation has shown that the combined discretionary and mandatory security enforcement effectively limits the unauthorized access to the medical database, without severely restricting the capabilities of the system.

A Distributed Secure System

When the individuals concerned are members of an organization, however, that organization may circumscribe their discretionary power to grant access to information by imposing a mandatory security policy to safeguard the interests of the organization as a whole. The most widely used scheme of this type is the multilevel security, or MLS, policy employed in military and government environments[1]. Here, each individual is assigned a clearance chosen from the four hierarchically ordered levels, Unclassified, Confidential, Secret, and Top Secret, and each item of information is assigned a classification chosen from the same four levels. The fundamental requirement is that no individual should see information classified above his clearance.