Firewalls and internet security : repelling the wily hacker /
William R. Cheswick, Steven M. Bellovin.
- Massachusetts: Addison-Wesley, 1994
- 306 p.
- Addison-Wesley Professional Computing Series .
CONTENIDO Preface xi Part I. Getting Started 1 1. Introduction 3 Why Security? 3 Picking a Security Policy 4 Strategies for a Secure Network 8 The Ethics of Computer Security 15 WARNING 17 2. An Overview of TCP/IP 19 The Different Layers 19 Routers and Routing Protocols 26 The Domain Name System 27 Standard Services 29 RPC-based Protocols 34 File Transfer Protocols 39 The r Commands 42 Information Services 44 The X11 System 47 Patterns of Trust 48 Part II. Building Your Own Firewall 49 3. Firewall Gateways 51 Firewall Philosophy 51 Situating Firewalls 53 Packet-Filtering Gateways 54 Application-Level Gateways 75 Circuit-Level Gateways 76 Supporting Inbound Services 78 Tunnels Good and Bad 79 Joint Ventures 80 What Firewalls Can't Do 82 4. How to Build an Application-Level Gateway 85 Policy 85 Hardware Configuration Options 86 Initial Installation 89 Gateway Tools 91 Installing Services 94 Protecting the Protectors 109 Gateway Administration 110 Safety Analysis_Why Our Setup Is Secure and Fail-Safe 113 Performance 115 The TIS Firewall Toolkit 115 Evaluating Firewalls 116 Living Without a Firewall 118 5. Authentication 119 User Authentication 120 Host-to-Host Authentication 123 6. Gateway Tools 125 Proxylib 125 Syslog 127 Watching the Network: Tcpdump and Friends 128 Adding Logging to Standard Daemons 130 7. Traps, Lures, and Honey Pots 133 What to Log 133 Dummy Accounts 140 Tracing the Connection 141 8. The Hacker's Workbench 143 Introduction 143 Discovery 145 Probing Hosts 148 Connection Tools 150 Routing Games 150 Network Monitors 152 Metastasis 152 Tiger Teams 155 Further Reading 156 Part III. A Look Back 157 9. Classes of Attacks 159 Stealing Passwords 159 Social Engineering 160 Bugs and Backdoors 161 Authentication Failures 163 Protocol Failures 164 Information Leakage 165 Denial-of-Service 165 10. An Evening with Berferd 167 Introduction 167 Unfriendly Acts 167 An Evening with Berferd 169 The Day After 174 The Jail 175 Tracing Berferd 177 Berferd Comes Home 178 11. Where the Wild Things Are: A Look at the Logs 181 A Year of Hacking 183 Proxy Use 189 Attack Sources 190 Noise on the Line 192 Part IV. Odds and Ends 195 12. Legal Considerations 197 Computer Crime Statutes 198 Log Files as Evidence 200 Is Monitoring Legal? 202 Tort Liability Considerations 206 13. Secure Communications over Insecure Networks 211 An Introduction to Cryptography 211 The Kerberos Authentication System 223 Link-Level Encryption 226 Network- and Transport-Level Encryption 227 Application-Level Encryption 229 14. Where Do We Go from Here? 235 A. Useful Free Stuff 239 Building Firewalls 240 Network Management and Monitoring Tools 243 Auditing Packages 244 Cryptographic Software 246 Information Sources 247 B. TCP and UDP Ports 249 Fixed Ports 249 MBone Usage 252 C. Recommendations to Vendors 253 Everyone 253 Hosts 253 Routers 254 Protocols 254 Firewalls 255 Bibliography 257 List of s 277 Index 279