Chapter 1: Fundamental SELinux Concepts
Security-Enhanced Linux (SELinux) brings additional security measures to your Linux system to further protect its resources. As part of the Linux kernel, it is a mandatory access control system supported by major Linux distributions. In this book, we cover all aspects of SELinux, from basic fundamentals to resolving SELinux issues, configuring applications to deal with SELinux, and even writing our own policies.
Before we embark on the details of SELinux, let's first cover the concepts of this technology: why SELinux uses labels to identify resources, how SELinux differs from traditional Linux access controls, how SELinux enforces security rules, and other mandatory access control systems that are supported in the Linux kernel. We will also see how the access control rules enforced by SELinux are provided through policy files. At the end of the chapter, we will cover an overview of the differences between SELinux implementations across Linux distributions.
In this chapter, we're going to cover the following main topics:
- Providing more security for Linux
- Labeling all resources and objects
- Defining and distributing policies
- Distinguishing between policies
