Book review: SELinux by Example: Using Security Enhanced Linux <i>by Frank Mayer, Karl MacMillan and David Caplan</i>

Security is one of the important reasons GNU/Linux is chosen over MS Windows. Many folks will claim that GNU/Linux just isn’t targeted as often. Could be—but it could also be that it isn’t targeted as often due to its design. SELinux takes this concept one step further. Not just satisfied with the inherent security, SELinux has been developed by a team of concerned professionals and is now included by default in the 2.6 kernel. Yes, you may have SELinux already and didn’t even know it.

The authors are all involved with SELinux and have contributed much to it. Frank Mayer chairs the SELinux Symposium and has published many papers on secure operating systems. He is also the CTO of Tresys Technology. Karl MacMillan has lead development efforts for many of SELinux’s features. He has also had many papers published. David Caplan has been active in figuring out SELinux policies for many different systems.

The book’s cover

This topic is probably not one you’ll spend the weekend reading about. For me, this would be a book to use at work to show management just how serious GNU/Linux can be about security. Fortunately, the authors do not expect their readers to go through the book “cover-to-cover” and they provide guidance on how to get the best use from the detailed material. Don't ignore this advice or you will find yourself dragging your feet a little after the first few chapters. This is a technical book, not a novel. But in this proper context, it is a book you may need.

If you are serious about security, you should have this book

The contents

There is a lot of information packed into these 456 pages. Not very many screenshots, but that wouldn’t really be appropriate anyway. Most of the examples are text files and they are displayed quite clearly. The command line instructions typically include the results you should expect from execution. This is as helpful as the instructions themselves and is done properly throughout the book. At seven by nine and a quarter inches, it will fit in just fine with your other technical books. Somehow the bright white cover ties in with security and just seems “clean”. A minor detail, but no accident I’m sure.

Who’s this book for?

If you are looking to take advantage of the security enhancements made available by SELinux, you should have this book. If you are going to be responsible for managing and writing SELinux policy, you should have this book.

Relevance to free software

Security is where free software can shine. While some will argue over a distributions GUI or argue over how software packages are installed and updated, you don’t hear many people arguing over security policies. With this book backing you up, you will be ready to take the argument to a level of detail that few are prepared for. But keep the discussions between professionals, nobody gets points for bashing the newbies.

The book and its examples are based on Redhat’s Fedora Core 4 (FC4). This is the environment used by the SELinux community and was the first distribution to fully support SELinux. Gentoo and Debian are additional distributions mentioned specifically as supporting SELinux as well.

Take security to a level of detail most folks will never go to


The authors are professionals. They are all seriously involved with SELinux and know their subject matter. Security is something you should really do right the first time. This book will show you details on how to make it happen.


Even for a technical book, this one struck me as a little dry. But don’t forget, I’m just one guy sitting at one PC. For somebody who’s job depended on keeping the network secure—this will probably end up being a favorite.

Title SELinux by Example
Author Frank Mayer, Karl MacMillan, David Caplan
Publisher Prentice Hall
ISBN 0131963694
Year 2006
Pages 456
CD included No
FS Oriented 10
Over all score 8

In short


This work is licensed under a Creative Commons Attribution 3.0 Unported License.