Snort for Dummies

385 Pages·2004·3.923 MB·English

by  Charlie Scott, Paul Wolfe, Bert Hayes

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Snort
™
FOR
DUMmIES
‰
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Snort
™
FOR
DUMmIES
‰
by Charlie Scott,Paul Wolfe,and Bert Hayes
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Snort™For Dummies®
Published by
Wiley Publishing, Inc.
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Hoboken, NJ 07030-5774
Copyright ©2004 by Wiley Publishing, Inc., Indianapolis, Indiana
Published by Wiley Publishing, Inc., Indianapolis, Indiana
Published simultaneously in Canada
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About the Authors
Charlie Scottis an Information Security Analyst for the City of Austin, where
he helps maintain the City’s network security infrastructure and helps analyze
intrusion detection data. He has nearly ten years of experience in the Internet
industry and has been an avid user of open source security software that entire
time. Charlie is a Certified Information Systems Security Professional (CISSP)
and a Cisco Certified Network Professional (CCNP).
Bert Hayesis a Security Technical Analyst for the State of Texas, where he
maintains network security for a medium sized agency. In Bert’s ten years
of IT industry experience, he has done everything from managing a corporate
IT shop during a successful IPO to performing white hat penetration tests for
corporate and government offices. He has long been a proponent of open
source solutions, and is a Red Hat Certified Engineer (RHCE).
Paul Wolfeis an independent information security consultant and author,
specializing in open source security.
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Authors’ Acknowledgments
This book benefited greatly from the research and writing contribution of
Mike Erwin, an early collaborator on this project. Mike is the president and
CEO of Symbiot, Inc., a developer of intelligent security infrastructure man-
agement system designed to interoperate with intrusion detection systems
and other pieces of security infrastructure. Mike has fifteen years of experi-
ence in network operations and security, has co-authored over a half-dozen
books, and is a Certified Information Systems Security Professional (CISSP).
The authors collectively bow to the developers of the myriad of security
tools covered in this book, especially Marty Roesch, for answering our ques-
tions and creating Snort in the first place!
The authors also thank Melody Layne, Pat O’Brien, and the rest of the Wiley
team for their hard work and prodding, and our agent Carole McClendon of
Waterside Productions. They also thank Jamie Pugh of Symbiot for his inci-
sive technical review.
Bert dedicates his portion of the book to everyone who would rather build
his or her own system than buy one off the shelf. He also acknowledges the
unwavering love and support of his wife Kate, the loyalty of his pets, and the
wisdom of his parents.
Paul thanks Nikolaus, Lukas, Rayna, Jesse and Brenda, whose support make
his work possible (and necessary . . .). And finally, thanks to Charlie for ruling
this project with the iron grip of a dictator. Bastard.
Charlie dedicates his portion of the book to everyone who has ever had to
clean up a cracked system — may it never happen again. He thanks his won-
derful wife, Mary, and his co-workers at the City of Austin for their support.
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Publisher’s Acknowledgments
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Some of the people who helped bring this book to market include the following:
Acquisitions, Editorial, and Composition
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Publishing and Editorial for TechnologyDummies
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Contents at a Glance
Introduction.................................................................1
Part I: Getting to Know Snort and Intrusion Detection.....5
Chapter 1: Looking Up Snort’s Nose................................................................................7
Chapter 2: Fitting In Snort...............................................................................................19
Chapter 3: Readying Your Preflight Checklist...............................................................29
Chapter 4: Makin’ Bacon: Installing Snort for Linux....................................................41
Chapter 5: Installing Snort and MySQL for Windows...................................................77
Part II: Administering Your Snort Box.........................105
Chapter 6: Snorting Through Logs and Alerts............................................................107
Chapter 7: Adding Visuals and Getting Reports.........................................................133
Chapter 8: Making Your Own Rules..............................................................................175
Chapter 9: What, Me Worry?.........................................................................................199
Chapter 10: Dealing with the Real Thing.....................................................................217
Part III: Moving Beyond the Basics............................241
Chapter 11: Reacting in Real Time...............................................................................243
Chapter 12: Keeping Snort Up to Date.........................................................................263
Chapter 13: Filling Your Farm with Pigs......................................................................275
Chapter 14: Using the Barnyard Output Tool.............................................................295
Part IV: The Part of Tens...........................................317
Chapter 15: Ten Cool Tools for Snort...........................................................................319
Chapter 16: Ten Snort Information Resources...........................................................327
Appendix A: What’s On the CD-ROM..........................331
Index.......................................................................337