2020ok  Directory of FREE Online Books and FREE eBooks

Free eBooks > Computers & Internet > Programming > Introductory & Beginning > General > Open Source Security Tools Practical Guide to Security Applications Jul 2004

Open Source Security Tools Practical Guide to Security Applications Jul 2004

by Tony Howlett

Download Book

If you are the author or the publisher, and would like to link to your site here, please contact us.

About Book

Book Description

This book sorts through the overwhelming mass of open source security tools, chooses a few of the best, and shows network and system administrators how to use them to solve common security problem. Open Source Security Tools is a practicum. It tells readers what they need to do to secure their networks, introduces best-in-class tools, and shows readers how to use them. For each security task described, Howlett reviews the best open source tools, shows readers how to use them, and takes them through a sample implementation and case studies. At the end of each chapter, Howlett will offer pointers to other good open source tools that are worth investigating. The companion CD includes fully dowloadable versions of the tools, so readers can work along with the text. Newcomers to security will leave with enough knowledge and experience to deploy solutions and further their IT careers. Readers will learn to: * Secure their perimeter with open source scanners like Nessus.* Receive early warning about attempted breakins from IDS systems like Snort.* Install a firewall to keep hackers at bay (Turtle).* Use encyrption to secure email and other sensitive data (PGP)* If the worst happens, run forensics tools to investigate a breakin after the fact, like Autopsy or SleuthKit.This book is part of the Bruce Perens Open Source Series.

From the Back Cover

Few frontline system administrators can afford to spend all day worrying about security. But in this age of widespread virus infections, worms, and digital attacks, no one can afford to neglect network defenses.

Written with the harried IT manager in mind, Open Source Security Tools is a practical, hands-on introduction to open source security tools. Seasoned security expert Tony Howlett has reviewed the overwhelming assortment of these free and low-cost solutions to provide you with the “best of breed” for all major areas of information security.

Inside, you’ll find everything from how to harden Linux and Windows systems to how to investigate breaches with Sleuth Kit, Autopsy Forensic Browser, and Forensic Tool Kit. For each security task described, the author reviews the best open source tools and how to use them and also provides a case study and sample implementation. Covered tasks include:

  • Installing an open source firewall using Ipchains, Iptables, Turtle firewall, or Smoothwall
  • Scanning ports and testing for vulnerabilities using Nmap, Nlog, Nmap for Windows, Nessus,and NessusWX
  • Using sniffers and network-intrusion systems, including Tcpdump, Ethereal, Windump, Snort™, and Snort™ for Windows
  • Tracking and analyzing collected data with Swatch, ACID, and NCC
  • Encrypting communications with PGP, GnuPG, SSH, and Free S/WAN

This handy reference also tackles the emerging field of wireless security and covers tools such as Kismet Wireless, Airsnort, and Netstumber.

About the Author

Tony Howlett is the president of Network Security Services, a computer-security application service provider built entirely on open source software. A Certified Information Systems Security Professional (CISSP) and GIAC Systems and Network Auditor (GNSA), he has fourteen years of experience, including running a major regional ISP/CLEC and building a nationwide ATM/DSL network. Mr. Howlett is a frequent speaker on computer security and technology topics and has written for SysAdmin, Computer Currents, Windows Web Solutions, Security Administrator, and other magazines.

Excerpt. © Reprinted by permission. All rights reserved.

Open source software is such an integral part of the Internet that is it safe to say that the Internet wouldn’t exist as we know it today without it. The Internet never would have grown as fast and as dynamically as it did without open source programs such as BIND, which controls the domain name system; Sendmail, which powers most e-mail servers; INN, which runs many news servers; Major Domo, which runs many of the thousands of mailing lists on the Internet; and of course the popular Apache Web server. One thing for sure is that the Internet is a lot cheaper due to open source software. For that, you can thank the Free Software Foundation, BSD UNIX, Linux and Linus Torvalds, and the thousands of nameless programmers who put their hard work and sweat into the programs that run today’s Internet.

While open source programs cover just about every aspect of computer software—from complete operating systems and games to word processors and databases—this book primarily deals with tools used in computer security. In the security field, there are programs that address every possible angle of IT security. There are open source firewalls, intrusion detection systems, vulnerability scanners, forensic tools, and cutting-edge programs for areas such as wireless communications. There are usually multiple choices in each category of mature, stable programs that compare favorably with commercial products. I have tried to choose the best of breed in each major area of information security (in my opinion, of course!). I present them in a detailed manner, showing you not just how to install and run them but also how to use them in your everyday work to have a more secure network. Using the open source software described in this book, you can secure your enterprise from both internal and external security threats with a minimal cost and maximum benefit for both the company and you personally.

I believe combining the concepts of information security with open source software offers one of the most powerful tools for securing your company’s infrastructure, and by extension the entire Internet. It is common knowledge that large-scale virus infections and worms are able to spread because many systems are improperly secured. I believe that by educating the rank-and-file system managers and giving them the tools to get the job done, we can make the Internet more secure, one network at a time.


The audience for this book is intended to be the average network or system administrator whose job duties are not specifically security and who has at least several years of experience. This is not to say that security gurus won’t get anything out of this book; there might be areas or tools discussed that are new to you. And likewise, someone just getting into IT will learn quite a bit by installing and using these tools. The concepts discussed and techniques used assume a minimal level of computer and network proficiency.

There is also a broad group of readers that is often overlooked by the many open source books. These are the Windows system administrators. The info-security elite often has a certain disdain for Windows-only administrators, and little has been written on quality open source software for Windows. However, the fact remains that Windows servers make up the lion’s share of the Internet infrastructure, and ignoring this is doing a disservice to them and the security community at large. While overall the book is still tilted towards Linux/UNIX because most open source programs are still Linux/UNIX-only, I have tried to put Windows-based security tools in every chapter. I’ve also included helpful hints and full explanations for those who have never run a UNIX machine.


This book covers most of the major areas of information security and the open source tools you can use to help secure them. The chapters are designed around the major disciplines of information security and key concepts are covered in each chapter.

This book also contains some quick tutorials on basic network terminology and concepts. I have found that while many technicians are well-schooled in their particular platforms or applications, they often lack an understanding of the network protocols and how they work together to get your information from point A to point B. Understanding these concepts are vital to securing your network and implementing these tools properly. So while this book may seem slanted towards the network side of security, most of the threats are coming from there these days, so this is the best place to start.

Coverage of each security tool is prefaced by a summary of the tool, contact information, and various resources for support and more information. While I give a fairly detailed look at the tools covered, whole books can and have been written on many of the programs discussed. These resources give you options for further research.

Helpful and sometimes humorous tips and tricks and tangents are used to accent or emphasize an area of particular importance. These are introduced by Flamey the Tech, our helpful yet sometimes acerbic mascot who is there to help and inform the newbies as well as keeping the more technical readers interested in sections where we actually make some minor modifications to the program code. He resembles the denizens you may encounter in the open source world. In exploring the open source world, you will meet many diverse, brilliant, and sometimes bizarre personalities (you have to be a least a little bent to spend as much unpaid time on these programs as some of us do). Knowing the proper etiquette and protocol will get you a lot farther and with fewer flames. On a more serious note, many of the tools in this book can be destructive or malicious if used in the wrong ways. You can unintentionally break the law if you use these tools in an uninformed or careless manner (for example, accidentally scanning IP addresses that aren’t yours with safe mode off). Flamey will always pipe up to warn you when this is a possibility.

Open Source Security Tool Index

Immediately following this Preface is a listing of all the tools and the pages where they are covered. This way you can skip all the background and go straight to installing the tools if you want.

Chapter 1: Information Security and Open Source Software

This chapter offers an introduction to the world of information security and open source software. The current state of computer security is discussed along with a brief history of the open source movement.

Chapter 2: Operating System Tools

This chapter covers the importance of setting up your security tool system as securely as possible. A tool for hardening Linux systems is discussed as well as considerations for hardening Windows systems. Several operating system-level tools are reviewed too. These basic tools are like a security administrator’s screwdriver and will be used again and again throughout the course of this book and your job.

Chapter 3: Firewalls

The basics of TCP/IP communications and how firewalls work are covered here before jumping into installing and setting up your own open source firewall.

Chapter 4: Port Scanners

This chapter delves deeper into the TCP/IP stack, especially the application layer and ports. It describes the installation and uses for a port scanner, which builds up to the next chapter.

Chapter 5: Vulnerability Scanners

This chapter details a tool that uses some of the earlier technology such as port scanning, but takes it a step further and actually tests the security of the open ports found. This security Swiss army knife will scan your whole network and give you a detailed report on any security holes that it finds.

Chapter 6: Network Sniffers

This chapter primarily deals with the lower levels of the OSI model and how to capture raw data off the wire. Many of the later tools use this basic technology, and it shows how sniffers can be used to diagnose all kinds of network issues in addition to tracking down security problems.

Chapter 7: Intrusion Detection Systems

A tool that uses the sniffer technology introduced in the previous chapter is used here to build a network intrusion detection system. Installation, maintenance, and optimal use are also discussed.

Chapter 8: Analysis and Management Tools

This chapter examines how to keep track of security data and log it efficiently for later review. It also looks at tools that help you analyze the security data and put it in a more usable format.

Chapter 9: Encryption Tools

Sending sensitive data over the Internet is a big concern these days, yet it is becoming more and more of a requirement. These tools will help you encrypt your communications and files with strong encryption as well as create IPsec VPNs.

Chapter 10: Wireless Tools

Wireless networks are becoming quite popular and the tools in this chapter will help you make sure that any wireless networks your company uses are secure and that there aren’t wireless LANs you don’t know about.

Chapter 11: Forensic Tools

The tools discussed in this chapter will help you investigate past break-ins and how to properly collect digital evidence.

Chapter 12: More On Open Source Software

Finally, this chapter will give you resources for finding out more about open source software. Various key Web sites, mailing lists, and other Internet-based resources are identified. Also, I give a number of ways to become more involved in the open source movement if you so desire.

Appendix A: Common Open Source Licenses

Contains the two main open source licenses, the GPL and BSD software licenses. >>-->



PLEASE READ: All comments must be approved before appearing in the thread; time and space constraints prevent all comments from appearing. We will only approve comments that are directly related to the article, use appropriate language and are not attacking the comments of others.

Message (please, no HTML tags. Web addresses will be hyperlinked):

Related Free eBooks

Related Tags

DIGG This story   Save To Google   Save To Windows Live   Save To Del.icio.us   diigo it   Save To blinklist
Save To Furl   Save To Yahoo! My Web 2.0   Save To Blogmarks   Save To Shadows   Save To stumbleupon   Save To Reddit