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Securing Linux 466_HTC_Linux_FM.qxd 10/2/07 10:05 AM Page iii How to Cheat at Securing Linux Mohan Krishnamurthy Eric S. Seagren Raven Alder Aaron W. Bayles Josh Burke Skip Carter Eli Faskha 466_HTC_Linux_FM.qxd 10/2/07 10:05 AM Page iv Elsevier, Inc., the author(s), and any person or firm involved in the writing, editing, or production (collectively “Makers”) of this book (“the Work”) do not guarantee or warrant the results to be obtained from the Work. There is no guarantee of any kind, expressed or implied, regarding the Work or its contents.The Work is sold AS IS and WITHOUT WARRANTY.You may have other legal rights, which vary from state to state. In no event will Makers be liable to you for damages, including any loss of profits, lost savings, or other incidental or consequential damages arising out from the Work or its contents. Because some states do not allow the exclusion or limitation of liability for consequential or incidental damages, the above limitation may not apply to you. You should always use reasonable care, including backup and other appropriate precautions, when working with computers, networks, data, and files. Syngress Media®, Syngress®,“Career Advancement Through Skill Enhancement®,”“Ask the Author UPDATE®,” and “Hack Proofing®,” are registered trademarks of Elsevier, Inc.“Syngress:The Definition of a Serious Security Library”™,“Mission Critical™,” and “The Only Way to Stop a Hacker is to Think Like One™” are trademarks of Elsevier, Inc. Brands and product names mentioned in this book are trademarks or service marks of their respective companies. PUBLISHED BY Syngress Publishing, Inc. Elsevier, Inc. 30 Corporate Drive Burlington, MA 01803 How to Cheat at Securing Linux Copyright © 2008 by Elsevier, Inc.All rights reserved. Printed in the United States of America. Except as permitted under the Copyright Act of 1976, no part of this publication may be reproduced or distributed in any form or by any means, or stored in a database or retrieval system, without the prior written permission of the publisher, with the exception that the program listings may be entered, stored, and executed in a computer system, but they may not be reproduced for publication. Printed in the United States of America 1 2 3 4 5 6 7 8 9 0 ISBN-13: 978-1-59749-207-2 Publisher:Amorette Pedersen Cover Designer: Michael Kavish Acquisitions Editor:Andrew Williams Indexer: Michael Ferreira Page Layout and Art: Patricia Lupien For information on rights, translations, and bulk sales, contact Matt Pedersen, Commercial Sales Director and Rights, at Syngress Publishing; email [email protected]. 466_HTC_Linux_FM.qxd 10/2/07 10:05 AM Page v Contributing Authors Mohan Krishnamurthy Madwachar (OPSA, OPST) is the GM – Network Security,Almoayed Group, Bahrain. Mohan is a key contributor to their projects division and plays an important role in the organization’s Network Security initiatives. Mohan comes from a strong networking, security and training background. His tenure with companies, such as Schlumberger Omnes and Secure Network Solutions India adds to his experience and expertise in implementing large and complex network and security projects. Mohan holds leading IT industry standard and vendor certifications in systems, networking and security. He is a member of the IEEE and PMI. Mohan would like to dedicate his contributions to this book to his brother Anand, his wife Preethi Anand and their sweet daughter Janani. Mohan has co-authored two books Designing & Building Enterprise DMZs (ISBN: 1597491004) and Configuring Juniper Networks NetScreen & SSG Firewalls (ISBN: 1597491187) published by Syngress. He also writes in newspaper columns on various subjects and has contributed to leading con- tent companies as a technical writer and a subject matter expert. Eric S. Seagren (CISA, CISSP-ISSAP,SCNP,CCNA, CNE-4, MCP+I, MCSE-NT) has 10 years of experience in the computer industry, with the last eight years spent in the financial services industry working for a Fortune 100 company. Eric started his computer career working on Novell servers and performing general network troubleshooting for a small Houston-based company. Since he has been working in the financial ser- vices industry, his position and responsibilities have advanced steadily. His duties have included server administration, disaster recovery responsibilities, business continuity coordinator,Y2K remediation, network vulnerability assessment, and risk management responsibilities. He has spent the last few years as an IT architect and risk analyst, designing and evaluating secure, scalable, and redundant networks. v 466_HTC_Linux_FM.qxd 10/2/07 10:05 AM Page vi Eric has worked on several books as a contributing author or technical editor.These include Hardening Network Security (McGraw-Hill), Hardening Network Infrastructure (McGraw-Hill), Hacking Exposed: Cisco Networks (McGraw-Hill), Configuring Check Point NGX VPN-1/FireWall-1 (Syngress), Firewall Fundamentals (Cisco Press), and Designing and Building Enterprise DMZs (Syngress). He has also received a CTM from Toastmasters of America. Aaron W. Bayles is a senior security consultant with Sentigy, Inc. of Houston,TX. He provides service to Sentigy’s clients with penetration testing, vulnerability assessment, and risk assessments for enterprise net- works. He has over 9 years experience with INFOSEC, with specific expe- rience in wireless security, penetration testing, and incident response.Aaron’s background includes work as a senior security engineer with SAIC in Virginia and Texas.He is also the lead author of the Syngress book, InfoSec Career Hacking, Sell your Skillz, Not Your Soul. Aaron has provided INFOSEC support and penetration testing for mul- tiple agencies in the U.S. Department of the Treasury, such as the Financial Management Service and Securities and Exchange Commission, and the Department of Homeland Security, such as U. S. Customs and Border Protection. He holds a Bachelor’s of Science degree in Computer Science with post-graduate work in Embedded Linux Programming from Sam Houston State University and is also a CISSP. Raven Alder is a Senior Security Engineer for IOActive, a consulting firm specializing in network security design and implementation. She specializes in scalable enterprise-level security, with an emphasis on defense in depth. She designs large-scale firewall and IDS systems, and then performs vulner- ability assessments and penetration tests to make sure they are performing optimally. In her copious spare time, she teaches network security for LinuxChix.org and checks cryptographic vulnerabilities for the Open Source Vulnerability Database. Raven lives in Seattle, WA. Raven was a contributor to Nessus Network Auditing (Syngress Publishing, ISBN: 1- 931836-08-6). vi 466_HTC_Linux_FM.qxd 10/2/07 10:05 AM Page vii Dr. Everett F. (Skip) Carter, Jr. is President of Taygeta Network Security Services (a division of Taygeta Scientific Inc.).Taygeta Scientific Inc. pro- vides contract and consulting services in the areas of scientific computing, smart instrumentation, and specialized data analysis.Taygeta Network Security Services provides security services for real-time firewall and IDS management and monitoring, passive network traffic analysis audits, external security reviews, forensics, and incident investigation. Skip holds a Ph.D. and an M.S. in Applied Physics from Harvard University. In addition he holds two Bachelor of Science degrees (Physics and Geophysics) from the Massachusetts Institute of Technology. Skip is a member of the American Society for Industrial Security (ASIS). He was contributing author of Syngress Publishing’s book, Hack Proofing XML (ISBN: 1-931836-50-7). He has authored several articles for Dr. Dobbs Journal and Computer Language as well as numerous scientific papers and is a former columnist for Forth Dimensions magazine. Skip resides in Monterey, CA, with his wife,Trace, and his son, Rhett. Josh Burke (CISSP) is an independent information security consultant in Seattle, Washington. He has held positions in networking, systems, and secu- rity over the past seven years in the technology, financial, and media sectors. A graduate of the business school at the University of Washington, Josh concentrates on balancing technical and business needs for companies in the many areas of information security. He also promotes an inclusive, positive security philosophy for companies, which encourages communicating the merits and reasons for security policies, rather than educating only on what the policies forbid. Josh is an expert in open-source security applications such as Snort, Ethereal, and Nessus. His research interests include improving the security and resilience of the Domain Name System (DNS) and the Network Time Protocol (NTP). He also enjoys reading about the mathematics and history of cryptography, but afterward often knows less about the subject than when he started. vii 466_HTC_Linux_FM.qxd 10/2/07 10:05 AM Page viii Eli Faskha (Security+, Check Point Certified Master Architect, CCSI, CCSE, CCSE+, MCP). Based in Panama City, Panama, Eli is Founder and President of Soluciones Seguras, a company that specializes in network security and is a Check Point Gold Partner and Nokia Authorized Partner. He was Assistant Technical Editor for Syngress’ Configuring Check Point NGX VPN-1/Firewall-1 (ISBN: 1597490318) book and Contributing Author for Syngress’ Building DMZs for the Enterprise (ISBN: 1597491004). Eli is the most experienced Check Point Certified Security Instructor and Nokia Instructor in the region, and
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