Building Secure Servers With Linux

Linux consistently turns up high in the list of popular Internet servers, whether it's for the Web, anonymous FTP, or general services like DNS and routing mail. But security is uppermost on the mind of anyone providing such a service. Any server experiences casual probe attempts dozens of time a day, and serious break-in attempts with some frequency as well. As the cost of broadband and other high-speed Internet connectivity has gone down, and its availability has increased, more Linux users are providing or considering providing Internet services such as HTTP, Anonymous FTP, etc., to the world at large. At the same time, some important, powerful, and popular Open Source tools have emerged and rapidly matured--some of which rival expensive commercial equivalents--making Linux a particularly appropriate platform for providing secure Internet services. Building Secure Servers with Linux will help you master the principles of reliable system and network security by combining practical advice with a firm knowledge of the technical tools needed to ensure security. The book focuses on the most common use of Linux--as a hub offering services to an organization or the larger Internet--and shows readers how to harden their hosts against attacks. Author Mick Bauer, a security consultant, network architect, and lead author of the popular Paranoid Penguin column in Linux Journal, carefully outlines the security risks, defines precautions that can minimize those risks, and offers recipes for robust security. The book does not cover firewalls, but covers the more common situation where an organization protects its hub using other systems as firewalls, often proprietary firewalls. The book includes: Precise directions for securing common services, including the Web, mail, DNS, and file transfer. Ancillary tasks, such as hardening Linux, using SSH and certificates for tunneling, and using iptables for firewalling. Basic installation of intrusion detection tools. Writing for Linux users with little security expertise, the author explains security concepts and techniques in clear language, beginning with the fundamentals. Building Secure Servers with Linux provides a unique balance of "big picture" principles that transcend specific software packages and version numbers, and very clear procedures on securing some of those software packages. An all-inclusive resource for Linux users who wish to harden their systems, the book covers general security as well as key services such as DNS, the Apache Web server, mail, file transfer, and secure shell. With this book in hand, you'll have everything you need to ensure robust security of your Linux system.

Building Secure Servers with Linux will help you master the principles of reliable system and network security by combining practical advice with a firm knowledge of the technical tools needed to ensure security. The book focuses on the most common use of Linux--as a hub offering services to an organization or the larger Internet. The book does not cover firewalls, but covers the more common situation where an organization protects its hub using other systems as firewalls, often proprietary firewalls. Writing for Linux users with little security expertise, the author explains security concepts and techniques in clear language beginning with the fundamentals. An all-inclusive resource for Linux users who wish to harden their systems, the book covers general security as well as key services such as DNS, the Apache Web server, mail, file transfer, and secure shell. With this book in hand, you'll have everything you need to ensure robust security of your Linux system.

A concise but comprehensive guide to providing the best possible security for a server, with examples and background to help you understand the issues involved. For each of the tasks or services covered, this book lays out the reasons for security, the risks and needs involved, the background to understand the solutions, and step by step guidelines for doing the job.

Linux consistently appears high up in the list of popular Internet servers, whether it's for the Web, anonymous FTP, or general services such as DNS and delivering mail. But security is the foremost concern of anyone providing such a service. Any server experiences casual probe attempts dozens of time a day, and serious break-in attempts with some frequency as well. This highly regarded book, originally titled Building Secure Servers with Linux , combines practical advice with a firm knowledge of the technical tools needed to ensure security. The book focuses on the most common use of Linux--as a hub offering services to an organization or the Internet--and shows readers how to harden their hosts against attacks. An all-inclusive resource for Linux users who wish to harden their systems, Linux Server Security covers general security such as intrusion detection and firewalling a hub, as well as key services such as DNS, the Apache Web server, mail, and secure shell. Author Michael D. Bauer, a security consultant, network architect, and lead author of the popular Paranoid Penguin column in the Linux Journal , carefully outlines the security risks, defines precautions that can minimize those risks, and offers recipes for robust security. He is joined on several chapters by administrator and developer Bill Lubanovic. A number of new security topics have been added for this edition, including: Database security, with a focus on MySQL Using OpenLDAP for authentication An introduction to email encryption The Cyrus IMAP service, a popular mail delivery agent The vsftpd FTP server Geared toward Linux users with little security expertise, the author explains security concepts and techniques in clear language, beginning with the fundamentals. Linux Server Security with Linux provides a unique balance of "big picture" principles that transcend specific software packages and version numbers, and very clear procedures on securing some of those software packages on several popular distributions. With this book in hand, you'll have both the expertise and the tools to comprehensively secure your Linux system.

Learn how to attack and defend the world’s most popular web server platform Linux Server Security: Hack and Defend presents a detailed guide for experienced admins, aspiring hackers and other IT professionals seeking a more advanced understanding of Linux security. Written by a 20-year veteran of Linux server deployment this book provides the insight of experience along with highly practical instruction. The topics range from the theory of past, current, and future attacks, to the mitigation of a variety of online attacks, all the way to empowering you to perform numerous malicious attacks yourself (in the hope that you will learn how to defend against them). By increasing your understanding of a hacker’s tools and mindset you're less likely to be confronted by the all-too-common reality faced by many admins these days: someone else has control of your systems. Master hacking tools and launch sophisticated attacks: perform SQL injections, deploy multiple server exploits and crack complex passwords. Defend systems and networks: make your servers invisible, be confident of your security with penetration testing and repel unwelcome attackers. Increase your background knowledge of attacks on systems and networks and improve all-important practical skills required to secure any Linux server. The techniques presented apply to almost all Linux distributions including the many Debian and Red Hat derivatives and some other Unix-type systems. Further your career with this intriguing, deeply insightful, must-have technical book. Diverse, broadly-applicable and hands-on practical, Linux Server Security: Hack and Defend is an essential resource which will sit proudly on any techie's bookshelf.

Welsh's guide has everything users need to understand, install, and start using the Linux operating system. New topics covered include laptops, cameras, scanners, sound, multimedia, and more.

Computer security is an ongoing process, a relentless contest between system administrators and intruders. A good administrator needs to stay one step ahead of any adversaries, which often involves a continuing process of education. If you're grounded in the basics of security, however, you won't necessarily want a complete treatise on the subject each time you pick up a book. Sometimes you want to get straight to the point. That's exactly what the new Linux Security Cookbook does. Rather than provide a total security solution for Linux computers, the authors present a series of easy-to-follow recipes--short, focused pieces of code that administrators can use to improve security and perform common tasks securely.The Linux Security Cookbook includes real solutions to a wide range of targeted problems, such as sending encrypted email within Emacs, restricting access to network services at particular times of day, firewalling a webserver, preventing IP spoofing, setting up key-based SSH authentication, and much more. With over 150 ready-to-use scripts and configuration files, this unique book helps administrators secure their systems without having to look up specific syntax. The book begins with recipes devised to establish a secure system, then moves on to secure day-to-day practices, and concludes with techniques to help your system stay secure.Some of the "recipes" you'll find in this book are: Controlling access to your system from firewalls down to individual services, using iptables, ipchains, xinetd, inetd, and more Monitoring your network with tcpdump, dsniff, netstat, and other tools Protecting network connections with Secure Shell (SSH) and stunnel Safeguarding email sessions with Secure Sockets Layer (SSL) Encrypting files and email messages with GnuPG Probing your own security with password crackers, nmap, and handy scripts This cookbook's proven techniques are derived from hard-won experience. Whether you're responsible for security on a home Linux system or for a large corporation, or somewhere in between, you'll find valuable, to-the-point, practical recipes for dealing with everyday security issues. This book is a system saver.

Linux® is being adopted by an increasing number of embedded systems developers, who have been won over by its sophisticated scheduling and networking, its cost-free license, its open development model, and the support offered by rich and powerful programming tools. While there is a great deal of hype surrounding the use of Linux in embedded systems, there is not a lot of practical information. Building Embedded Linux Systems is the first in-depth, hard-core guide to putting together an embedded system based on the Linux kernel. This indispensable book features arcane and previously undocumented procedures for: Building your own GNU development toolchain Using an efficient embedded development framework Selecting, configuring, building, and installing a target-specific kernel Creating a complete target root filesystem Setting up, manipulating, and using solid-state storage devices Installing and configuring a bootloader for the target Cross-compiling a slew of utilities and packages Debugging your embedded system using a plethora of tools and techniques Details are provided for various target architectures and hardware configurations, including a thorough review of Linux's support for embedded hardware. All explanations rely on the use of open source and free software packages. By presenting how to build the operating system components from pristine sources and how to find more documentation or help, this book greatly simplifies the task of keeping complete control over one's embedded operating system, whether it be for technical or sound financial reasons.Author Karim Yaghmour, a well-known designer and speaker who is responsible for the Linux Trace Toolkit, starts by discussing the strengths and weaknesses of Linux as an embedded operating system. Licensing issues are included, followed by a discussion of the basics of building embedded Linux systems. The configuration, setup, and use of over forty different open source and free software packages commonly used in embedded Linux systems are also covered. uClibc, BusyBox, U-Boot, OpenSSH, thttpd, tftp, strace, and gdb are among the packages discussed.