Installation guide

6.4. Runlevels............................................................................................................ 103
6.5. Fonts................................................................................................................... 105
6.6. Additional Resources......................................................................................... 106
II. Security Reference ..................................................................................................................... 109
7. Pluggable Authentication Modules (PAM)....................................................................... 111
7.1. Advantages of PAM ........................................................................................... 111
7.2. PAM Configuration Files ................................................................................... 111
7.3. PAM Modules .................................................................................................... 112
7.4. PAM Module Control Flags............................................................................... 113
7.5. PAM Module Paths ............................................................................................ 114
7.6. PAM Module Arguments ................................................................................... 114
7.7. Sample PAM Configuration Files ...................................................................... 114
7.8. PAM and Device Ownership.............................................................................. 116
7.9. Additional Resources......................................................................................... 117
8. TCP Wrappers and xinetd .............................................................................................. 119
8.1. What Are TCP Wrappers? ................................................................................. 119
8.2. Host-Based Access Control Lists....................................................................... 119
8.3. Access Control Using xinetd .......................................................................... 122
8.4. Additional Resources......................................................................................... 126
9. SSH Protocol..................................................................................................................... 129
9.1. Features of SSH ................................................................................................. 129
9.2. Event Sequence of an SSH Connection ............................................................. 130
9.3. Layers of SSH Security...................................................................................... 130
9.4. OpenSSH Configuration Files ........................................................................... 132
9.5. More Than a Secure Shell.................................................................................. 133
9.6. Require SSH for Remote Connections .............................................................. 134
10. Kerberos.......................................................................................................................... 137
10.1. Advantages of Kerberos................................................................................... 137
10.2. Kerberos Disadvantages................................................................................... 137
10.3. Kerberos Terminology ..................................................................................... 137
10.4. How Kerberos Works ....................................................................................... 139
10.5. Kerberos and PAM........................................................................................... 140
10.6. Configuring a Kerberos 5 Server ..................................................................... 140
10.7. Configuring a Kerberos 5 Client ...................................................................... 142
10.8. Additional Resources ....................................................................................... 142
11. Tripwire........................................................................................................................... 145
11.1. How to Use Tripwire........................................................................................ 145
11.2. Installing the Tripwire RPM ............................................................................ 146
11.3. Customizing Tripwire ...................................................................................... 147
11.4. Initialize the Tripwire Database....................................................................... 149
11.5. Running an Integrity Check ............................................................................. 150
11.6. Examining Tripwire Reports............................................................................ 150
11.7. Updating the Tripwire Database ...................................................................... 152
11.8. Updating the Tripwire Policy File ................................................................... 153
11.9. Updating the Tripwire Configuration File ....................................................... 154
11.10. Tripwire File Location Reference.................................................................. 155
11.11. Additional Resources ..................................................................................... 156