Ktutil
Kerberos Keytab Management with Ktutil
Ktutil is a command-line utility designed for managing entries within Kerberos keytab files. Keytab files store principals and their associated keys, which are crucial for enabling services to authenticate users or other services without requiring interactive password entry. This tool provides a straightforward way to interact with these files, ensuring secure and efficient authentication processes.
Core Ktutil Operations
The primary function of ktutil is to manipulate keytab files. Below are the essential commands for managing these files:
# Load an existing keytab file
ktutil
ktutil: rkt <keytab_file>
# List the entries in the currently loaded keytab
ktutil
ktutil: list
# Write the current keytab entries to a new keytab file
ktutil
ktutil: wkt <keytab_file>
# Quit the ktutil session
ktutil
ktutil: quit
Advanced Keytab Entry Management
Beyond basic loading and saving, ktutil allows for detailed management of individual entries within a keytab:
# Add a new entry to the keytab
ktutil
ktutil: add_entry -password -p <principal> -k <kvno> -e <encryption_type>
# Remove a specific entry from the keytab
ktutil
ktutil: delete_entry <entry_number>
# Change the password of a principal and update the keytab
ktutil
ktutil: change_password -p <principal> -newpass
Scripting Ktutil Commands
For automation and batch processing, ktutil can execute commands from a script file:
# Start ktutil and directly execute commands from a script (example)
ktutil < script_file
# Explanation: The commands in 'script_file' will be executed in order. Each line should contain a valid ktutil command such as 'rkt', 'add_entry', 'wkt', etc.
This capability is invaluable for setting up authentication mechanisms in automated deployment pipelines or for managing large numbers of principals and their keys efficiently.