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 target settings and policies

Before we embark on the journey of using these four automation frameworks, we need to clarify what we want to accomplish. After all, to truly compare automation frameworks, we need to test each framework with the same tests each time.

The idempotency of actions

Whenever we create a remote management environment with a central repository, we need to consider the impact of running remote management activities on the system. A very common best practice, strongly adopted by all these frameworks, is idempotency.

An idempotent task is a task that will not modify a system if the system's state is already how it should be. Or, differently put, repeatedly executing a task does not affect the system or the processes that run on it if nothing needs to be changed. As an example, consider loading an SELinux module: if the module is already loaded, then the module should not be reloaded. If it isn't loaded yet, then we will load the...