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

Introducing the reference policy

The reference policy, available through https://github.com/SELinuxProject/refpolicy, is the source SELinux policy for most, if not all, Linux distributions out there. While it is possible that the plain reference policy will not work out of the box for any Linux distribution (as many Linux distributions add their own touch to the policy, or adjust it so it fits the applications and support tooling installed), the development methodology, structure, and approach used by the reference policy are applicable to all major distribution policies.

We recommend checking out the SELinux policy of your distribution to see and easily modify SELinux policies for the system. In this chapter, we'll use a checkout of the reference policy:

$ git clone https://github.com/SELinuxProject/refpolicy.git

The SELinux policy repositories for the Linux distributions should be documented by the distributions themselves. A few example repositories are listed next...