Using trusted facilities

Using trusted facilities

Because no computer system is completely free from risk, we refer to systems as ``trusted'' rather than ``secure.'' A trusted system achieves a greater level of control over access to information by providing mechanisms to detect and possibly prevent unauthorized access, along with additional means to confirm that these mechanisms are functioning properly. The C2 level of trust means that the system meets specific criteria in its security policy, accountability, assurance, testing, and documentation.

All UNIX operating systems provide some measure of security by allowing users have passwords to log on and offering the ability to specify access permissions for the owner, group, and other for each file or directory. SCO OpenServer maintains compatibility with existing UNIX system mechanisms and provides enhanced security features and trusted facilities.

The examples in this chapter illustrate how to use trusted facilities to create a protected subsystem, which is an application that uses the trusted facilities to control access permission to its executable and data files.

Consider the following when deciding whether to implement your application using trusted facilities:

Virtually all UNIX operating systems support the standard facilities, so programs that use the standard facilities are more portable.
Trusted facilities provide a much greater level of security and are recommended for applications that manipulate data requiring protection from unauthorized disclosure.