Client Authentication:Ubuntu

	Warning:
	If your reading this then this page is incomplete. Don't follow the instructions below because they haven't been verified

	Warning:
	This is based upon limited testing and a small number of users via a VirtualBox virtual machine installation of Ubuntu 9.10. YMMV

Ubuntu 9.10 Authentication

Introduction

The following details the setup of Ubuntu 9.10 Karmic Koala as a desktop to authenticate users against SME. The method has been tested using Ubuntu installed in a VirtualBox virtual machine on a Windows XP host.

Install Ubuntu

Download the Ubuntu .iso and install. When prompted for a user name give a non-SME user such as 'administrator', as this first user effectively becomes a local user with sudo root access. Complete install, login and apply all updates.

Additional Packages

Use the System - Administration - Synaptic Package Manager to install additional packages

auth_client_config
winbind
libpam_mount
smbfs ??

Samba Modifications

Open a Terminal cli and change to root privileges

sudo su

Open and edit /etc/samba/smb.conf. Find the relevant lines and alter them or uncomment them as below. Some lines may not exist and may need to be added.

workgroup=<WORKGROUP>
wins server=<ip of sme server>
security=domain
password server=<ip of sme server>
winbind use default domain=yes
socket options=TCP_NODELAY
idmap uid=5000-20000
idmap gid=5000-20000
template shell=/bin/bash
template homedir=/home/%D/%U
winbind enum user=yes
winbind enum groups=yes
winbind cache time=10

Replace <WORKGROUP> above with the workgroup name of your SME server. Replace <ip of sme server> above with the internal network ip address of your SME server.

Edit

Authentication Modifications

	Warning:
	Altering the pam system authentication files can seriously effect your ability to login in to the system. Take a backup of the /etc/pam.d directory and /etc/nsswitch.conf. Have a live CD available to give access and re-apply the backup files if you make a mistake and/or get locked out

Open and edit /etc/nsswitch.conf and find the hosts: line. Change it to

hosts: file wins dns

Change to the auth-client-config tool profile directory

cd /etc/auth-client-config/profile.d

Create and edit a new file called acc-sme, and enter

[sme-nt4-1]
nss_group=group:        compat winbind
nss_netgroup=netgroup:  nis
nss_passwd=passwd:      compat winbind
nss_shadow=shadow:      compat winbind
pam_auth=auth	[success=2 default=ignore]  pam_winbind.so	
         auth	[success=1 default=ignore]  pam_unix.so       nullok  use_first_pass  use_authtok
         auth	requisite	            pam_deny.so
         auth	required		    pam_permit.so
         auth	required		    pam_securetty.so
         auth	optional		    pam_mount.so      enable_pam_password
pam_account=account  [success=2 new_authtok_reqd=done default=ignore]	pam_winbind.so
            account  [success=1 default=ignore]	                pam_unix.so	use_first_pass	use_authtok
            account  requisite			                        pam_deny.so
            account  required			                        pam_permit.so
pam_password=password	[success=2 default=ignore]  pam_unix.so obscure sha512
             password	[success=1 default=ignore]  pam_winbind.so	use_first_pass	md5 use_authtok
             password	requisite		    pam_deny.so
             password	required		    pam_permit.so
             password	optional	            pam_gnome_keyring.so
pam_session=session  [default=1]  pam_permit.so
            session  requisite	   pam_deny.so
            session  required	   pam_permit.so
            session  optional	   pam_winbind.so
            session  required	   pam_unix.so 
            session  optional	   pam_ck_connector.so  nox11
            session  required	   pam_mkhomedir.so	skel=/etc/skel	umask=0022
            session  optional	   pam_mount.so	        enable_pam_password

	Tip:
	You can use auth-client-config -S > acc-sme to create the file first, containing the current pam files configuration, and then just modify

Save the file. Apply the pam authorisation changes

auth-client-config -a -p sme

Automount User Home Directories at Login

cd /etc/security

Open and edit pam_mount.conf.xml file. Find the 'Volume Definitions' section. Add a volume line below the header

<volume fstype="cifs" server="<SMESERVER>" path="homes" mountpoint="~/nethome" options="nosuid,nodev" />

Replace <SMESERVER> above with the samba name of your SME server. This will mount the users 'home' directory from SME into a directory called 'nethome' in their local home directory.

Login and Test

Logout of Ubuntu.

Login as a valid SME server user on your system, just giving username and password. No need for DOMAIN/user as samba configured above to use the default workgroup

Authentication against SME should proceed and the user log in. A home directory on the local machine should be created as /home/DOMAIN/user, and a sub directory to that called 'nethome' mounted to the users home directory on the SME server. The mount point should also appear on the users gui desktop.

Issues / ToDo

The above was tested on a VirtualBox virtual machine. The login appears to stall after username and password entered due to the mount of the home directory, but this does complete after a little while. Appears to be due to NAT traversal and WINS lookup as VM is using NAT and a different subnet. Couldn't get bridged mode to work, and haven't installed on a dedicated machine on the same subnet to confirm. Login is a little slow therefore.

Haven't tested or altered the pam password configuration to see if password changes are handled correctly.