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Copyright |
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Preface |
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Unix "Security"? |
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Scope of This Book |
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Which Unix System? |
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Conventions Used in This Book |
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Comments and Questions |
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Acknowledgments |
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A Note to Would-Be Attackers |
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Part I:
Computer Security Basics |
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Chapter 1.
Introduction: Some Fundamental Questions |
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Section 1.1.
What Is Computer Security? |
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Section 1.2.
What Is an Operating System? |
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Section 1.3.
What Is a Deployment Environment? |
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Section 1.4.
Summary |
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Chapter 2.
Unix History and Lineage |
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Section 2.1.
History of Unix |
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Section 2.2.
Security and Unix |
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Section 2.3.
Role of This Book |
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Section 2.4.
Summary |
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Chapter 3.
Policies and Guidelines |
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Section 3.1.
Planning Your Security Needs |
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Section 3.2.
Risk Assessment |
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Section 3.3.
Cost-Benefit Analysis and Best Practices |
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Section 3.4.
Policy |
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Section 3.5.
Compliance Audits |
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Section 3.6.
Outsourcing Options |
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Section 3.7.
The Problem with Security Through Obscurity |
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Section 3.8.
Summary |
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Part II:
Security Building Blocks |
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Chapter 4.
Users, Passwords, and Authentication |
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Section 4.1.
Logging in with Usernames and Passwords |
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Section 4.2.
The Care and Feeding of Passwords |
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Section 4.3.
How Unix Implements Passwords |
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Section 4.4.
Network Account and Authorization Systems |
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Section 4.5.
Pluggable Authentication Modules (PAM) |
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Section 4.6.
Summary |
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Chapter 5.
Users, Groups, and the Superuser |
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Section 5.1.
Users and Groups |
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Section 5.2.
The Superuser (root) |
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Section 5.3.
The su Command: Changing Who You Claim to Be |
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Section 5.4.
Restrictions on the Superuser |
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Section 5.5.
Summary |
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Chapter 6.
Filesystems and Security |
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Section 6.1.
Understanding Filesystems |
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Section 6.2.
File Attributes and Permissions |
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Section 6.3.
chmod: Changing a File's Permissions |
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Section 6.4.
The umask |
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Section 6.5.
SUID and SGID |
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Section 6.6.
Device Files |
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Section 6.7.
Changing a File's Owner or Group |
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Section 6.8.
Summary |
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Chapter 7.
Cryptography Basics |
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Section 7.1.
Understanding Cryptography |
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Section 7.2.
Symmetric Key Algorithms |
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Section 7.3.
Public Key Algorithms |
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Section 7.4.
Message Digest Functions |
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Section 7.5.
Summary |
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Chapter 8.
Physical Security for Servers |
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Section 8.1.
Planning for the Forgotten Threats |
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Section 8.2.
Protecting Computer Hardware |
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Section 8.3.
Preventing Theft |
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Section 8.4.
Protecting Your Data |
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Section 8.5.
Story: A Failed Site Inspection |
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Section 8.6.
Summary |
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Chapter 9.
Personnel Security |
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Section 9.1.
Background Checks |
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Section 9.2.
On the Job |
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Section 9.3.
Departure |
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Section 9.4.
Other People |
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Section 9.5.
Summary |
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Part III:
Network and Internet Security |
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Chapter 10.
Modems and Dialup Security |
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Section 10.1.
Modems: Theory of Operation |
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Section 10.2.
Modems and Security |
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Section 10.3.
Modems and Unix |
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Section 10.4.
Additional Security for Modems |
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Section 10.5.
Summary |
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Chapter 11.
TCP/IP Networks |
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Section 11.1.
Networking |
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Section 11.2.
IP: The Internet Protocol |
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Section 11.3.
IP Security |
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Section 11.4.
Summary |
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Chapter 12.
Securing TCP and UDP Services |
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Section 12.1.
Understanding Unix Internet Servers and Services |
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Section 12.2.
Controlling Access to Servers |
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Section 12.3.
Primary Unix Network Services |
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Section 12.4.
Managing Services Securely |
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Section 12.5.
Putting It All Together: An Example |
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Section 12.6.
Summary |
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Chapter 13.
Sun RPC |
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Section 13.1.
Remote Procedure Call (RPC) |
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Section 13.2.
Secure RPC (AUTH_DES) |
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Section 13.3.
Summary |
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Chapter 14.
Network-Based Authentication Systems |
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Section 14.1.
Sun's Network Information Service (NIS) |
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Section 14.2.
Sun's NIS+ |
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Section 14.3.
Kerberos |
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Section 14.4.
LDAP |
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Section 14.5.
Other Network Authentication Systems |
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Section 14.6.
Summary |
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Chapter 15.
Network Filesystems |
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Section 15.1.
Understanding NFS |
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Section 15.2.
Server-Side NFS Security |
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Section 15.3.
Client-Side NFS Security |
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Section 15.4.
Improving NFS Security |
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Section 15.5.
Some Last Comments on NFS |
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Section 15.6.
Understanding SMB |
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Section 15.7.
Summary |
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Chapter 16.
Secure Programming Techniques |
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Section 16.1.
One Bug Can Ruin Your Whole Day . . . |
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Section 16.2.
Tips on Avoiding Security-Related Bugs |
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Section 16.3.
Tips on Writing Network Programs |
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Section 16.4.
Tips on Writing SUID/SGID Programs |
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Section 16.5.
Using chroot( ) |
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Section 16.6.
Tips on Using Passwords |
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Section 16.7.
Tips on Generating Random Numbers |
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Section 16.8.
Summary |
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Part IV:
Secure Operations |
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Chapter 17.
Keeping Up to Date |
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Section 17.1.
Software Management Systems |
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Section 17.2.
Updating System Software |
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Section 17.3.
Summary |
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Chapter 18.
Backups |
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Section 18.1.
Why Make Backups? |
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Section 18.2.
Backing Up System Files |
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Section 18.3.
Software for Backups |
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Section 18.4.
Summary |
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Chapter 19.
Defending Accounts |
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Section 19.1.
Dangerous Accounts |
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Section 19.2.
Monitoring File Format |
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Section 19.3.
Restricting Logins |
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Section 19.4.
Managing Dormant Accounts |
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Section 19.5.
Protecting the root Account |
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Section 19.6.
One-Time Passwords |
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Section 19.7.
Administrative Techniques for Conventional Passwords |
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Section 19.8.
Intrusion Detection Systems |
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Section 19.9.
Summary |
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Chapter 20.
Integrity Management |
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Section 20.1.
The Need for Integrity |
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Section 20.2.
Protecting Integrity |
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Section 20.3.
Detecting Changes After the Fact |
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Section 20.4.
Integrity-Checking Tools |
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Section 20.5.
Summary |
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Chapter 21.
Auditing, Logging, and Forensics |
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Section 21.1.
Unix Log File Utilities |
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Section 21.2.
Process Accounting: The acct/pacct File |
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Section 21.3.
Program-Specific Log Files |
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Section 21.4.
Designing a Site-Wide Log Policy |
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Section 21.5.
Handwritten Logs |
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Section 21.6.
Managing Log Files |
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Section 21.7.
Unix Forensics |
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Section 21.8.
Summary |
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Part V:
Handling Security Incidents |
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Chapter 22.
Discovering a Break-in |
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Section 22.1.
Prelude |
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Section 22.2.
Discovering an Intruder |
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Section 22.3.
Cleaning Up After the Intruder |
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Section 22.4.
Case Studies |
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Section 22.5.
Summary |
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Chapter 23.
Protecting Against Programmed Threats |
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Section 23.1.
Programmed Threats: Definitions |
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Section 23.2.
Damage |
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Section 23.3.
Authors |
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Section 23.4.
Entry |
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Section 23.5.
Protecting Yourself |
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Section 23.6.
Preventing Attacks |
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Section 23.7.
Summary |
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Chapter 24.
Denial of Service Attacks and Solutions |
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Section 24.1.
Types of Attacks |
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Section 24.2.
Destructive Attacks |
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Section 24.3.
Overload Attacks |
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Section 24.4.
Network Denial of Service Attacks |
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Section 24.5.
Summary |
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Chapter 25.
Computer Crime |
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Section 25.1.
Your Legal Options After a Break-in |
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Section 25.2.
Criminal Hazards |
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Section 25.3.
Criminal Subject Matter |
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Section 25.4.
Summary |
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Chapter 26.
Who Do You Trust? |
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Section 26.1.
Can You Trust Your Computer? |
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Section 26.2.
Can You Trust Your Suppliers? |
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Section 26.3.
Can You Trust People? |
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Section 26.4.
Summary |
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Part VI:
Appendixes |
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Appendix A.
Unix Security Checklist |
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Section A.1.
Preface |
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Section A.2.
Chapter 1: Introduction: Some Fundamental Questions |
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Section A.3.
Chapter 2: Unix History and Lineage |
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Section A.4.
Chapter 3: Policies and Guidelines |
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Section A.5.
Chapter 4: Users, Passwords, and Authentication |
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Section A.6.
Chapter 5: Users, Groups, and the Superuser |
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Section A.7.
Chapter 6: Filesystems and Security |
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Section A.8.
Chapter 7: Cryptography Basics |
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Section A.9.
Chapter 8: Physical Security for Servers |
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Section A.10.
Chapter 9: Personnel Security |
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Section A.11.
Chapter 10: Modems and Dialup Security |
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Section A.12.
Chapter 11: TCP/IP Networks |
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Section A.13.
Chapter 12: Securing TCP and UDP Services |
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Section A.14.
Chapter 13: Sun RPC |
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Section A.15.
Chapter 14: Network-Based Authentication Systems |
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Section A.16.
Chapter 15: Network Filesystems |
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Section A.17.
Chapter 16: Secure Programming Techniques |
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Section A.18.
Chapter 17: Keeping Up to Date |
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Section A.19.
Chapter 18: Backups |
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Section A.20.
Chapter 19: Defending Accounts |
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Section A.21.
Chapter 20: Integrity Management |
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Section A.22.
Chapter 21: Auditing, Logging, and Forensics |
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Section A.23.
Chapter 22: Discovering a Break-In |
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Section A.24.
Chapter 23: Protecting Against Programmed Threats |
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Section A.25.
Chapter 24: Denial of Service Attacks and Solutions |
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Section A.26.
Chapter 25: Computer Crime |
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Section A.27.
Chapter 26: Who Do You Trust? |
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Section A.28.
Appendix A: Unix Security Checklist |
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Section A.29.
Appendix B: Unix Processes |
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Section A.30.
Appendixes C, D, and E: Paper Sources, Electronic Sources, and Organizations |
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Appendix B.
Unix Processes |
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Section B.1.
About Processes |
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Section B.2.
Signals |
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Section B.3.
Controlling and Examining Processes |
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Section B.4.
Starting Up Unix and Logging In |
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Appendix C.
Paper Sources |
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Section C.1.
Unix Security References |
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Section C.2.
Other Computer References |
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Appendix D.
Electronic Resources |
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Section D.1.
Mailing Lists |
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Section D.2.
Web Sites |
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Section D.3.
Usenet Groups |
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Section D.4.
Software Resources |
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Appendix E.
Organizations |
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Section E.1.
Professional Organizations |
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Section E.2.
U.S. Government Organizations |
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Section E.3.
Emergency Response Organizations |
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Colophon |
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Index |
