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Kerberos权威指南 Kerberos The Definitive Guide.pdf
Kerberos: The Definitive Guide
SPECIAL OFFER: Upgrade this ebook with O’Reilly
Preface
Organization of This Book
Conventions Used in This Book
Comments and Questions
Thanks...
1. Introduction
Origins
Modern History
The time-sharing model
The client-server model
Project Athena
What Is Kerberos?
Goals
Evolution
Early Kerberos (v1, v2, v3)
Kerberos 4
Kerberos 5
New Directions
Other Products
DCE
Globus Security Infrastructure
SESAME
2. Pieces of the Puzzle
The Three As
Authentication
Authorization
Auditing
Directories
Privacy and Integrity
Encryption
Message Integrity
Kerberos Terminology and Concepts
Realms, Principals, and Instances
Service and host principals
Kerberos 4 principals
Kerberos 5 principals
Keys, Salts, and Passwords
The Key Distribution Center
The Authentication Server
The Ticket Granting Server
Tickets
The ticket (or credential) cache
Putting the Pieces Together
3. Protocols
The Needham-Schroeder Protocol
Kerberos 4
The Authentication Server and the Ticket Granting Server
String-to-Key Transformation
The Key Version Number
Password Changing
Kerberos 5
The World’s Shortest ASN.1 Tutorial
The Authentication Server and the Ticket Granting Server
New Encryption Options
Ticket Options
Kerberos 5-to-4 Ticket Translation
Pre-Authentication
Other Protocol Features and Extensions
String-to-Key Transformation
Password Changing
The Alphabet Soup of Kerberos-Related Protocols
The Generic Security Services API (GSSAPI)
The Simple and Protected GSSAPI Negotiation Mechanism (SPNEGO)
4. Implementation
The Basic Steps
Planning Your Installation
Choose the Platform and Operating System
Choose a KDC Package
MIT
Heimdal
Windows domain controllers
Before You Begin
KDC Installation
MIT
Building the distribution
Creating your realm
Starting the servers
A quick test
Adding slave KDCs
Heimdal
Building the distribution
Creating your realm
Starting the servers
A quick test
Adding slave KDCs
Windows Domain Controller
Creating your realm
DNS and Kerberos
Setting Up KDC Discovery Over DNS
DNS Domain Name-to-Realm Mapping
Client and Application Server Installation
Unix as a Kerberos Client
Mac OS X as a Kerberos Client
Windows as a Kerberos Client
5. Troubleshooting
A Quick Decision Tree
Debugging Tools
Errors and Solutions
Errors Obtaining an Initial Ticket
Unsynchronized Clocks
Incorrect or Missing Kerberos Configuration
Server Hostname Misconfiguration
Encryption Type Mismatches
6. Security
Kerberos Attacks
Other Attacks
Protocol Security Issues
Dictionary and Brute-Force Attacks
Replay Attacks
Man-in-the-Middle Attacks
Security Solutions
Requiring Pre-Authentication
MIT
Heimdal
Windows domain controllers
Enforcing Secure Passwords
Heimdal
MIT
Windows domain controllers
Enforcing Password Lifetimes and History
MIT
Heimdal
Windows domain controllers
Protecting Your KDC
Protecting a Unix KDC
Protecting a Windows Domain Controller
Continual Maintenance
Firewalls, NAT, and Kerberos
Kerberos Network Ports
Kerberos and NAT
Auditing
Enabling Logging
MIT
Heimdal
Windows domain controllers
Understanding the Logs
MIT
Heimdal
Windows domain controllers
7. Applications
What Does Kerberos Support Mean?
Services and Keytabs
Transparent Kerberos Login with PAM
Configuring PAM
Mac OS X and the Login Window
Kerberos and Web-Based Applications
Building the mod_auth_kerb Apache Module
Configuring mod_auth_kerb
The Simple Authentication and Security Layer (SASL)
Building the Distribution
SASL Configuration
Configuring saslauthd
Kerberos-Enabled Server Packages
Electronic Mail (Cyrus IMAP)
Building and configuring the distribution
Testing the authentication
Directory Services (OpenLDAP)
Building, configuring, and testing the distribution
Remote Login (OpenSSH)
Building the distribution
Configuring the distribution
Kerberos-Enabled Client Packages
Kerberized Secure Shell Clients
Reflection X
Using existing credential caches with Reflection X
Electronic Mail
Qualcomm Eudora
Apple Mail.app
More Kerberos-Enabled Packages
8. Advanced Topics
Cross-Realm Authentication
Implementing Cross-Realm Relationships
Using Kerberos 4 Services with Kerberos 5
Windows Issues
Encryption Algorithm Support
Cached Login Credentials
Disabling the cached credentials feature
Windows Active Directory Authorization Field
Windows and Unix Interoperability
Using a Windows Domain Controller as a KDC for Unix Clients
Creating Unix keytabs from a Windows domain controller
Using a Non-Microsoft KDC for Windows Clients
Cross-realm trust
Standalone Windows machine
9. Case Study
The Organization
Planning
Planning the Kerberos Realms
Existing Network Layout
Kerberos KDC Planning
Implementation
Implementing UNIX.SAMPLE.COM
Building and installing the Kerberos KDC software
Realm configuration files
Creating the realm
Setting up slave replication
Installing the Kerberos software on client and application servers
Establishing Cross-Realm Relationships with SAMPLE.COM
Implementing LABS.SAMPLE.COM
Building and installing the Kerberos KDC software
Realm configuration files
Creating the realm
Installing the Kerberos software on client and application servers
Configuring Applications
10. Kerberos Futures
Public Key Extensions
Public Key Cryptography
Combining public key and symmetric key ciphers
Public key cryptography key distribution
Initial Authentication (PKINIT)
Cross-Realm (PKCROSS)
Smart Cards
Smart Cards and the Kerberos Protocol
Better Encryption
Kerberos Referrals
User Principal Canonicalization
Service Principal Canonicalization
Cross-Realm Referrals
Web Services
A. Administration Reference
MIT
Connecting to kadmin
Reference Section
listprincs
Reference Section
getprinc
Reference Section
addprinc
Reference Section
modprinc
Reference Section
cpw
Reference Section
delprinc
Reference Section
ktadd
Ktutil
clear
list
rkt
addent
delent
wkt
Heimdal
Connecting to kadmin
list
get
add
modify
cpw
delete
ext_keytab
Ktutil
list
add
remove
get
Windows Domain Controllers
Adding a principal
Modifying principal attributes
Changing passwords
Deleting principals
Adding keys into keytabs
Configuration File Format
libdefaults
appdefaults
realms
domain_realm
logging
capaths
Index
About the Author
Colophon
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Mike Loukides
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