Maximum Linux Security

Anonymous is a self-described Unix and Perl fanatic who lives in southern California with his wife Michelle and a half-dozen computers. He currently runs an Internet security consulting company and is at work building one of the world's largest computer security archives. He also moonlights doing contract programming for several Fortune 500 firms. John Ray is an award-winning developer and security consultant with more than 16 years of programming and administration experience. He has worked on projects for the FCC, The Ohio State University, Xerox, and the state of Florida, as well as serving as IT Director for Blue Cosmos Design, Inc. Ray has written/contributed to more than 10 titles currently in print, ranging from Using TCP/IP: Special Edition to Sams Teach Yourself Dreamweaver UltraDev 4 in 21 Days.

(NOTE: Each chapter concludes with a Summary.)

Introduction.
I. LINUX SECURITY BASICS.

1. Introducing Linux Security.


What Is Linux? Linux as a Standalone System. Linux as an Intranet/Internet Server. A Linux Security Overview.

2. Physical Security


Server Location and Physical Access. Network Topology. Network Hardware. Workstations and Security.

3. Installation Issues.


About Various Linux Distributions, Security, and Installation. Partitions and Security. Choosing Network Services During Installation. Boot Loaders.

4. Basic Linux System Administration.


The Basic Idea. Creating and Managing Accounts. Performing Administrative Tasks with su. Access Control. Permissions and Ownership. A Closer Look at Groups. Bringing Down Your System.

II. LINUX USER SECURITY.

5. Password Attacks.


What Is a Password Attack? How Linux Generates and Stores Passwords. The Data Encryption Standard (DES). Case Study: Cracking Linux Passwords via Dictionary Attack. Password Shadowing and the shadow Suite. After Installing the shadow Suite. Other Password Security Issues. Pluggable Authentication Modules. Still Other Password Security Solutions.

6. Data Attacks.


When Is Data Security Necessary? Forms of Data Security. Common Encryption Algorithms. mcrypt: Installation and Usage. GnuPG: Installing and Using a Public Key Encryption Utility. Steganography-Time for Something Completely Different. Additional Resources.

III. LINUX NETWORK SECURITY.

7. Malicious Code.


What Is Malicious Code? Detecting Malicious Code. Other File Integrity Checking Software.

8. Sniffers and Electronic Eavesdropping.


How Sniffers Work. Case Studies: Performing a Few Simple Sniffer Attacks. Other Sniffers and Network Monitoring Tools. Risks Posed by Sniffers. Defending Against Sniffer Attacks. Further Reading.

9. Scanners.


What Is a Scanner? Scanner Building Blocks and Scanner Evolution. How Scanners Fit into Your Security Regimen. Various Scanner Tools. Defending Against Scanner Attacks. Interesting Resources.

10. Spoofing.


What Is Spoofing All About? TCP and IP Spoofing. Case Study: A Simple Spoofing Attack. Preventing IP Spoofing Attacks. ARP Spoofing. DNS Spoofing. Other Strange Spoofing Attacks. Couic. Further Reading.

IV. LINUX INTERNET SECURITY.

11. FTP Security.


File Transfer Protocol. FTP's Default Security Features. SSH File Transfers. Specific FTP Application Security.

12. Mail Security.


SMTP Servers and Clients. sendmail Security Basics. Replacing sendmail with Qmail.

13. Telnet and SSH Security.


Telnet's Security History. Secure Telnet Systems. deslogin. SRA Telnet from Texas A&M University. The Stanford SRP Telnet/FTP Package. Secure Shell (ssh). scp: The Secure Copy Remote Fle Copy Program. Providing ssh Services in a Heterogeneous Network. ssh Security Issues. Additional Resources.

14. Web Server Security.


Eliminating Nonessential Services. Web Server Security. Adding Directory Access Control with Basic HTTP Authentication. Weaknesses in Basic HTTP Authentication. HTTP and Cryptographic Authentication. Running a chroot Web Environment. WebDAV. Accreditation and Certification.

15. Secure Web Protocols.


The Problem. Secure Sockets Layer (SSL) from Netscape Communications Corporation. Installing mod_ssl.

16. Secure Web Development.


Development Risk Factors: A Wide Overview. Spawning Shells. Buffer Overruns. Paths, Directories, and Files. Embedded Programming Languages. Automated CGI Testing Tools. Other Online Resources.

17. File Sharing Security.


Linux as a File Server. Samba. Netatalk. NFS Security. Virtual Private Networks.

18. Denial-of-Service Attacks.


What Is a Denial-of-Service Attack? Risks Posed by Denial-of-Service Attacks. How This Chapter Is Laid Out. Network Hardware DoS Attacks. Attacks on Linux Networking. Attacks on Linux Applications. Other DoS Attacks. Defending Against Denial-of-Service Attacks. Online Resources.

19. Linux and Firewalls.


What Is a Firewall? Assessing Whether You Really Need a Firewall. Internet Gateway/Firewalls. tcpd: TCP Wrappers. ipfwadm. ipchains. iptables. Free Firewall Tools and Add-ons for Linux. Commercial Firewalls. Additional Resources.

20. Intrusion Detection.


What Is Intrusion Detection? Basic Intrusion Detection Concepts. Some Interesting Intrusion Detection Tools. Practical Intrusion Detection.

21. Logs and Audit Trails.


What Is Logging, Exactly? Logging in Linux. Other Interesting Logging and Audit Tools.

22. Disaster Recovery.


What Is Disaster Recovery? Steps to Take Before Building Your Linux Network. Choosing Your Backup Tools. Simple Archiving: tarring and Zipping Your Files and Directories. Types of Backups and Backup Strategies. Backup Packages. Odds and Ends.

V. APPENDIXES.

Appendix A. Linux Security Command Reference.


.htaccess. .htpasswd. ACUA (An Add-On). amadmin. amanda. amcheck. amcleanup. amdump. amrestore. Angel Network Monitor (An Add-On). AppleVolumes.default. APS (An Add-On). arp. bootpd. cfdisk. chmod. chown. chroot. CIPE Crypto IP Encapsulation (An Add-On). crypt. ctrlaltdel. Dante (An Add-On). Deception Toolkit (An Add-On). DOC (Domain Obscenity Control, an Add-On). dns_lint (An Add-On). dnswalk (An Add-On). Ethereal (An Add-On). exports. exscan (An Add-On). FakeBO (An Add-On). fdisk. finger. fingerd. ftphosts. ftpaccess. ftpd. ftpshut. ftpwho. GNU Privacy Guard (An Add-On). halt. hosts_access. hosts.allow. hosts.deny. hosts_options. hosts.equiv. HostSentry from the Abacus Project. htpasswd. httpd. identd. IdentTCPscan (An Add-On). inetd.conf. ip_filter (An Add-On). IPAC (An Add-On). IPchains. ipfwadm. IPTables. IPv4 & IPv6 Sniffer. ISS (An Add-On). KSniffer (An Add-On). last. Logcheck from the Abacus Project (An Add-On). lsof (An Add-On). MAT (Monitoring and Administration Tool, an Add-On). WebDAV (mod_dav-an Apache Add-On). mod_ssl (An Apache Add-On). MOM (An Add-On). msystem (An Add-On That's Made for Unix but Can Work with Linux). NEPED (Network Promiscuous Ethernet Detector, an Add-On). Nessus (An Add-On). netstat. NMAP (The Network Mapper, an Add-On). npasswd (An Add-On). ntop (An Add-On). OpenSSL. passwd. passwd+ (An Add-On). pgp4pine. ping. ps. qmail (An Add-On). QueSo (An Add-On). rcmd. rcp. reboot. rlogin. rhosts. rhosts.dodgy (An Add-On). rsh. scp. PortSentry from the Abacus Project. services. shadow. Shadow in a Box (An Add-On). showmount. shutdown. SINUS (An Add-On). smb.conf. Snort (An Add-On). SocketScript (An Add-On). ssh. ssh-add. ssh-agent. ssh-keygen. sshd. Strobe (An Add-On). sudo. Swan (An Add-On). sXid Secure (An Add-On). sysklogd. System Administrator's Tool for Analyzing Networks (SATAN, an Add-On). tcpd (TCP Wrappers). tcpdchk. tcpdmatch. tcpdump. tftp. The Linux Shadow Password Suite (An Add-On). traceroute. traffic-vis (An Add-On). Trinux (An Add-On). TripWire (An Add-On). trafgraf. trojan.pl. ttysnoop. vipw. visudo. w.. who. whois. xinetd.conf. Xlogmaster (An Add-On).

Appendix B. Linux Security Index-Older Linux Security Issues.
Appendix C. Other Useful Linux Security Tools.
Appendix D. Sources for More Information.


Linux Security Patches, Updates, and Advisories. Mailing Lists. Usenet Newsgroups.

Appendix E. Glossary.
Index.