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

Securing high-speed InfiniBand networks

The InfiniBand standard is a relatively recent (in network history) technology that enables very high throughput and very low latency. It accomplishes this by having a very low overhead on the network layer (protocol) and direct access from user applications to the network level. This direct access also has implications for SELinux, as the Linux kernel is no longer actively involved in the transport of data across an InfiniBand link.

Let's first look at what InfiniBand looks like, after which we can see how to still apply SELinux controls to its communication flows.

Directly accessing memory

One of the main premises of InfiniBand is to allow user applications to have direct access to the network. By itself, InfiniBand is a popular Remote Direct Memory Access (RDMA) implementation, which has received significant support from vendors. We find RDMA actively used in high-performance clusters.

Because of the direct access, controls...