Book Image

SELinux System Administration

By : Sven Vermeulen
Book Image

SELinux System Administration

By: Sven Vermeulen

Overview of this book

NSA Security-Enhanced Linux (SELinux) is a set of patches and added utilities to the Linux kernel to incorporate a strong, flexible, mandatory access control architecture into the major subsystems of the kernel. With its fine-grained yet flexible approach, it is no wonder Linux distributions are firing up SELinux as a default security measure. SELinux System Administration covers the majority of SELinux features through a mix of real-life scenarios, descriptions, and examples. Everything an administrator needs to further tune SELinux to suit their needs are present in this book. This book touches on various SELinux topics, guiding you through the configuration of SELinux contexts, definitions, and the assignment of SELinux roles, and finishes up with policy enhancements. All of SELinux's configuration handles, be they conditional policies, constraints, policy types, or audit capabilities, are covered in this book with genuine examples that administrators might come across. By the end, SELinux System Administration will have taught you how to configure your Linux system to be more secure, powered by a formidable mandatory access control.
Table of Contents (13 chapters)

Chapter 4. Process Domains and File-level Access Controls

When we work on an SELinux-enabled system, gathering information about the contexts associated with the files and processes is extremely important. We also need to understand how these contexts are used in policies and what the applicable security rules are for a specific process.

In this chapter, we will:

  • Work with file contexts and learn where they are stored

  • Understand how contexts are assigned

  • Look at how processes get into the context they are in

  • Get our first taste of the SELinux policy and how we can query it

We end with another SELinux feature called constraints and how it is used to provide the user-based access control feature.