Book Image

SELinux System Administration, Third Edition - Third Edition

By : Sven Vermeulen
Book Image

SELinux System Administration, Third Edition - Third Edition

By: Sven Vermeulen

Overview of this book

Linux is a dominant player in many organizations and in the cloud. Securing the Linux environment is extremely important for any organization, and Security-Enhanced Linux (SELinux) acts as an additional layer to Linux system security. SELinux System Administration covers basic SELinux concepts and shows you how to enhance Linux system protection measures. You will get to grips with SELinux and understand how it is integrated. As you progress, you’ll get hands-on experience of tuning and configuring SELinux and integrating it into day-to-day administration tasks such as user management, network management, and application maintenance. Platforms such as Kubernetes, system services like systemd, and virtualization solutions like libvirt and Xen, all of which offer SELinux-specific controls, will be explained effectively so that you understand how to apply and configure SELinux within these applications. If applications do not exert the expected behavior, you’ll learn how to fine-tune policies to securely host these applications. In case no policies exist, the book will guide you through developing custom policies on your own. By the end of this Linux book, you’ll be able to harden any Linux system using SELinux to suit your needs and fine-tune existing policies and develop custom ones to protect any app and service running on your Linux systems.
Table of Contents (22 chapters)
1
Section 1: Using SELinux
8
Section 2: SELinux-Aware Platforms
14
Section 3: Policy Management

Summary

In this chapter, we saw how to enable and disable SELinux, both on a complete system level as well as a per-service level using various methods: kernel boot options, an SELinux configuration file, or plain commands. One such command is semanage permissive, which can disable SELinux protections for a single service.

Next, we saw where SELinux logs its events and how to interpret them, which is one of the most common tasks an administrator has to undertake when dealing with SELinux. To assist us with this interpretation, we can use tools such as setroubleshoot, sealert, and audit2why. We also touched upon several utilities related to Linux auditing to help us sift through various events.

In the next chapter, we will look at the first administrative task on SELinux systems: managing user accounts, their associated SELinux roles, and security clearances for the resources on the system.