From Fedora Project Wiki

Revision as of 21:08, 24 July 2013 by Jhrozek (talk | contribs)

Description

Use nss-pam-ldapd to gain access to trusted domain users

Setup

  1. Make sure your FreeIPA server is set up as in QA:Testcase_freeipa_trust_establish.
  2. Make sure nss-pam-ldapd is installed. This test uses RHEL-6.3 as an example, but the steps should be similar for other distribution or OS

How to test

Add test users and groups on the IPA server

When testing the legacy client, we will begin by creating a user and a group he is a member of on the server first to establish a baseline. 

$ kinit admin
$ ipa user-add --first=test --last=user tuser
$ ipa group-add --desc="test group" tgroup
$ ipa group-add-member --users=tuser tgroup

Also set some password for the newly created user so that we can log in using his credentials. 

$ ipa passwd tuser

Install required packages

The package installation step differs for every OS or distribution. For nss-pam-ldapd, simply install the packages using yum: 

 # yum install nss-pam-ldapd pam_ldap authconfig

The authconfig utility will help us configure the PAM stack.

Configure nss-pam-ldapd and pam_ldap

Next the nss-pam-ldapd needs to be configured. The configuration will point to a "compat tree" which is a parallel LDAP tree autogenerated from the main tree and tailored so that it matches the expectations legacy clients might have. The configuration includes two important items:

  1. LDAP URI - The URI is simply the host name of the IPA server prefixed with ldap://. For example, if the hostname was srv.ipa.example.org, then the URI would be ldap://srv.ipa.example.org
  2. LDAP search base - The LDAP search base we need consists of the base DN prefixed with "cn=compat", which is the container the compat tree lives in. To get the base DN, take the IPA domain name and substitute each dot for a "dc=". For example, the IPA domain ipa.example.org would yield base DN dc=ipa,dc=example,dc=org. The full search base you want to use would then be cn=compat,dc=ipa,dc=example,dc=org

Using authconfig

Configuring the system to authenticate with IPA using authconfig is a matter of one shell command once you know the LDAP URI and the search base. 

authconfig --updateall --enableldap --enableldapauth \
           --ldapserver=ldap://srv.ipa.example.org \
           --ldapbasedn=cn=compat,dc=ipa,dc=example,dc=com

Manually

  1. configure nsswitch.conf
  2. configure PAM
  3. configure nslcd

Identity lookups of IPA users and groups

Try to request data about the user that was created on the start of this test: 

$ getent passwd tuser
$ getent group tgroup
$ id tuser

The commands above should reflect that tuser is member of tgroup.

Authentication as IPA user

ssh client.example.org -l tuser

Identity lookups of trusted users and groups

When requesting the user from a trusted domain, the username must be fully qualified in the form of username@ad-domain. Additionaly, to conform with nss-pam-ldapd limitation, the username and domain name must be lowercased to match the name in the compat tree with respect to case.

To request a from the trusted domain: 

$ getent passwd administrator@ad.example.org

Authentication as trusted user

Again, the username must be fully qualified and lowercased: 

ssh client.example.org -l administrator@ad.example.org

Expected Results

All the test steps should end with the specified results.

Retrieved from "https://fedoraproject.org/w/index.php?title=QA:Testcase_freeipa_use_nss_pam_ldapd_to_give_access_to_trusted_domain_users&oldid=346428"