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


SELinux maps Linux users onto SELinux users and defines the roles that a user is allowed to be in through the SELinux user definitions. We learned how to manage those mappings and SELinux users with the semanage application and were able to grant the right roles to the right people.

We also saw how the same commands are used to grant the proper sensitivity to the user and how we can describe these levels in the setrans.conf file. We used the chcat tool to do most of the category-related management activities.

After assigning roles to the users, we saw how to jump from one role to another using newrole, sudo, runcon, and run_init. We ended this chapter with important insight into how SELinux integrates in the Linux authentication process and how to tune a Linux system further using a couple of SELinux-aware PAM modules.

In the next chapter, we will learn to manage the labels on files and processes and see how we can query the SELinux policy rules.