Book Image

SELinux System Administration. - Second Edition

Book Image

SELinux System Administration. - Second Edition

Overview of this book

Do you have the crucial job of protecting your private and company systems from malicious attacks and undefined application behavior? Are you looking to secure your Linux systems with improved access controls? Look no further, intrepid administrator! This book will show you how to enhance your system’s secure state across Linux distributions, helping you keep application vulnerabilities at bay. This book covers the core SELinux concepts and shows you how to leverage SELinux to improve the protection measures of a Linux system. You will learn the SELinux fundamentals and all of SELinux’s configuration handles including conditional policies, constraints, policy types, and audit capabilities. These topics are paired with genuine examples of situations and issues you may come across as an administrator. In addition, you will learn how to further harden the virtualization offering of both libvirt (sVirt) and Docker through SELinux. By the end of the book you will know how SELinux works and how you can tune it to meet your needs.
Table of Contents (16 chapters)
SELinux System Administration - Second Edition
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface

Information flow analysis


Another analytical investigation of SELinux policy is information flow analysis. Unlike domain transitions, which look at how one domain can gain a certain set of permissions through transitions toward other domains, information flow analysis looks at how a domain could leak (purposefully or not) information toward another domain.

Information flow analysis is performed by looking at all operations that occur between two types. A source type can be read by a domain, which subsequently can write information to another type. This simple approach is a two-step flow analysis.

However, it is not as simple as just checking read and write operations (although that is of course perfectly possible). Information can be leaked through file names, file descriptors, and more. Information flow analysis must take all these approaches into account.

Using apol for information flow analysis

After loading a SELinux policy, select Information Flow Analysis as the analysis method. The following...