Using Ldap And Kerberos - Novell LINUX ENTERPRISE SERVER 11 - SECURITY Manual

You should now be able to connect using Kerberos authentication. Use klist to ver-
ify that you have a valid ticket then connect to the SSH server. To force SSH protocol
version 1, specify the -1 option on the command line.
TIP: Additional Information
The file /usr/share/doc/packages/openssh/README.kerberos dis-
cusses the interaction of OpenSSH and Kerberos in more detail.

6.4.11 Using LDAP and Kerberos

When using Kerberos, one way to distribute the user information (such as user ID,
groups,and home directory) in your local network is to use LDAP. This requires a strong
authentication mechanism that prevents packet spoofing and other attacks. One solution
is to use Kerberos for LDAP communication, too.
OpenLDAP implements most authentication flavors through SASL, the simple authen-
tication session layer. SASL is basically a network protocol designed for authentication.
The SASL implementation is cyrus-sasl, which supports a number of different authen-
tication flavors. Kerberos authentication is performed through GSSAPI (General Secu-
rity Services API). By default, the SASL plug-in for GSSAPI is not installed. Install it
manually with rpm -ivh cyrus-sasl-gssapi-*.rpm.
To enable Kerberos to bind to the OpenLDAP server, create a principal
ldap/ldap.example.com and add that to the keytab.
By default, the LDAP server slapd runs as user and group ldap, while the keytab file
is readable by root only. Therefore, either change the LDAP configuration so the
server runs as root or make the keytab file readable by the group ldap. The latter is
done automatically by the OpenLDAP start script (/etc/init.d/ldap) if the keytab
file has been specified in the OPENLDAP_KRB5_KEYTAB variable in /etc/
sysconfig/openldap and the OPENLDAP_CHOWN_DIRS variable is set to yes,
which is the default setting. If OPENLDAP_KRB5_KEYTAB is left empty, the default
keytab under /etc/krb5.keytab is used and you must adjust the privileges yourself
as described below.
Network Authentication with Kerberos 105