Labels and Security Policy

Site security policy is the security policy that an organization establishes to protect its proprietary information. With Trusted Extensions software, labels and mandatory access control (MAC) can be part of this policy. Labels implement a set of rules that is a part of system security policy. System security policy is the set of rules that is enforced by system software to protect information that is being processed on the system. The term “security policy” can refer to the policy itself or to the implementation of the policy.

All systems that are configured with Trusted Extensions have labels. Labels are specified in a label_encodings file. For a description of the file, see the label_encodings(4) man page. For descriptions of the encodings files that Trusted Extensions provides, see Sources for Encodings Files.

Trusted Extensions installs a default version of the label_encodings file. The default version supplies several commercial labels. This version can sometimes be used in non-production environments for learning purposes. A site can also customize one of the label_encodings files that Trusted Extensions provides. For an example of a site-specific file, see Appendix A, Encodings File for SecCompany (Example).

Every system in a Trusted Extensions network needs its own copy of the site's label_encodings file. For interoperability, the label_encodings file on every system in the network must be compatible. At the very least, each system must recognize the labels on every other system.

Certain types of labels must be defined. The security administrator specifies the numeric values and the bits that define the internal representation of labels. Users and roles view the textual representation of labels. The labeling software translates between the internal form and the textual form. The label_encodings file provides the rules for translating the internal representation of labels to their textual form. The textual form can be visible on the desktop. The internal representation is recorded in the audit trail and is interpreted by the praudit command.

The security administrator is the person who defines and plans the implementation of an organization's security policy. The security administrator establishes information protection procedures, makes sure that users and administrators are properly trained, and monitors compliance.

The Security Administrator role is created in the software. The role is assigned to one or more administrators who fully understand Trusted Extensions administration. These administrators are cleared to view and protect the highest level of information that is processed by Trusted Extensions. One responsibility of the security administrator is to create the site's label_encodings file to replace the version that is installed by default. The administrator can also decide whether labels are visible on the desktop. Even when labels are not visible, objects and processes on the system are labeled, and MAC is enforced.

Trusted Extensions provides the Security Administrator role with the tools and capabilities to put the organization's security policy into effect. To assume the role, you first log in as a regular user, then you assume the role. At your site, the security administrator who defines the site's security policy might or might not be the same person who implements the policy.