Linux Firewalls: Enhancing Security with nftables and Beyond, 4th Edition

The Definitive Guide to Building Firewalls with Linux

As the security challenges facing Linux system and network administrators have grown, the security tools and techniques available to them have improved dramatically. In Linux^® Firewalls, Fourth Edition, long-time Linux security expert Steve Suehring has revamped his definitive Linux firewall guide to cover the important advances in Linux security.

An indispensable working resource for every Linux administrator concerned with security, this guide presents comprehensive coverage of both iptables and nftables. Building on the solid networking and firewalling foundation in previous editions, it also adds coverage of modern tools and techniques for detecting exploits and intrusions, and much more.

Distribution neutral throughout, this edition is fully updated for today’s Linux kernels, and includes current code examples and support scripts for Red Hat/Fedora, Ubuntu, and Debian implementations. If you’re a Linux professional, it will help you establish an understanding of security for any Linux system, and for networks of all sizes, from home to enterprise.

Inside, you’ll find just what you need to

• Install, configure, and update a Linux firewall running either iptables or nftables
• Migrate to nftables, or take advantage of the latest iptables enhancements
• Manage complex multiple firewall configurations
• Create, debug, and optimize firewall rules
• Use Samhain and other tools to protect filesystem integrity, monitor networks, and detect intrusions
• Harden systems against port scanning and other attacks
• Uncover exploits such as rootkits and backdoors with chkrootkit

Table of Contents

Part I: Packet Filtering And Basic Security Measures
Chapter 1 Preliminary Concepts Underlying Packet-Filtering Firewalls
Chapter 2 Packet-Filtering Concepts
Chapter 3 Iptables: The Legacy Linux Firewall Administration Program
Chapter 4 Nftables: The Linux Firewall Administration Program
Chapter 5 Building And Installing A Standalone Firewall

Part II: Advanced Issues, Multiple Firewalls, And Perimeter Networks
Chapter 6 Firewall Optimization
Chapter 7 Packet Forwarding
Chapter 8 Nat—Network Address Translation
Chapter 9 Debugging The Firewall Rules
Chapter 10 Virtual Private Networks

Part III: Beyond Iptables And Nftables
Chapter 11 Intrusion Detection And Response
Chapter 12 Intrusion Detection Tools
Chapter 13 Network Monitoring And Attack Detection
Chapter 14 Filesystem Integrity

Part IV: Appendices
Appendix A: Security Resources
Appendix B: Firewall Examples And Support Scripts
Appendix C: Glossary
Appendix D: Gnu Free Documentation License