Red Hat Summit53장. Using constrained delegation in IdM
The constrained delegation enables one service to access other services on your behalf. You grant only limited authority for one service instead of giving full access to all your credentials.
53.1. Constrained delegation in Identity Management
The Service for User to Proxy (S4U2proxy) extension provides a service that obtains a service ticket to another service on behalf of a user. This feature is known as constrained delegation. The second service is typically a proxy performing some work on behalf of the first service, under the authorization context of the user. Using constrained delegation eliminates the need for the user to delegate their full ticket-granting ticket (TGT).
Identity Management (IdM) traditionally uses the Kerberos S4U2proxy feature to allow the web server framework to obtain an LDAP service ticket on the user’s behalf. The IdM-AD trust system also uses constrained delegation to obtain a cifs principal.
You can use the S4U2proxy feature to configure a web console client to allow an IdM user that has authenticated with a smart card to achieve the following:
- Run commands with superuser privileges on the RHEL host on which the web console service is running without being asked to authenticate again.
-
Access a remote host using
SSHand access services on the host without being asked to authenticate again.
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