Book Image

SELinux System Administration. - Second Edition

Book Image

SELinux System Administration. - Second Edition

Overview of this book

Do you have the crucial job of protecting your private and company systems from malicious attacks and undefined application behavior? Are you looking to secure your Linux systems with improved access controls? Look no further, intrepid administrator! This book will show you how to enhance your system’s secure state across Linux distributions, helping you keep application vulnerabilities at bay. This book covers the core SELinux concepts and shows you how to leverage SELinux to improve the protection measures of a Linux system. You will learn the SELinux fundamentals and all of SELinux’s configuration handles including conditional policies, constraints, policy types, and audit capabilities. These topics are paired with genuine examples of situations and issues you may come across as an administrator. In addition, you will learn how to further harden the virtualization offering of both libvirt (sVirt) and Docker through SELinux. By the end of the book you will know how SELinux works and how you can tune it to meet your needs.
Table of Contents (16 chapters)
SELinux System Administration - Second Edition
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface

Summary


We saw how to toggle SELinux policy booleans using tools such as setsebool and how to get more information about booleans, both from their description (using the semanage boolean command) and the rules they influence (using sesearch).

Next, we saw how custom SELinux policy modules can be loaded and removed and which different types of development formats can be used for building custom SELinux policies. We created our own policy modules to enhance the SELinux policy using various examples such as user domain definitions, web application types, and SECMARK types.

We also saw how existing policies can be replaced rather than just augmented with additional rules. Replacing policies is, after all, the only way that a policy can be reduced (less permissive).

In the next chapter, we will use various tools to analyze the existing SELinux policy. This is needed for administrators to verify that the policy supports the security rules that the administrator has in mind and that confined users...