“Workplace Join” with ADFS 3.0 Device Registration Services and our ‘Workplace Join Hitman’ PowerShell App to the rescue !

Domain Join is what we have had for a long time, tight admin control, group policy, managing the desktop in full glory and control. "Workplace Join is much lighter, and is about authenticating an unknown device like a Surface RT, iOS or Android device. We will put a certificate on the device, and can challenge the device for this as part of claims based authentication to applications or other resources such as data, plus there is no admin control of the device, it remains under the control of the end user.

When coupled with BYO device management with a solution like Windows Intune, you can apply policy, deploy apps and control access to resources on machines that you otherwise have no control over."

Through the new Workplace Join feature within R2, AD FS becomes a focal point for mobile access in the enterprise and an integral component in the Microsoft Bring Your Own Device (BYOD) vision with Windows Intune. Workplace Join allows unmanaged or untrusted operating systems such as Windows RT / Windows 8.1 and IOS to be moved into a more controlled access context, by allowing their registration and affiliation with Active Directory.

Workplace Join is made possible by the Device Registration Service (DRS) that is included with the Active Directory Federation Role in Windows Server 2012 R2. When a device is Workplace Joined, the DRS provisions a device object in Active Directory and sets a certificate on the consumer device that is used to represent the device identity. The DRS is meant to be both internal and external facing. Companies that deploy both DRS and the Web Application Proxy will be able to Workplace Join devices from any internet connected location. To further secure this process, additional factors can be also used with Windows Azure Active Authentication (Phone Factor).

Lost Device Protection

As covered earlier, devices registered via ‘Workplace Join’ are registered within Active Directory in the following container ;

CN=<Device ID>,CN=RegisteredDevices,DC=mydomain,DC=com.

Lost devices can be denied access by disabling or deleting the appropriate object within AD (I moved the device objects to another OU to test this). Access through AD FS is immediately revoked for the workplace joined client.

From testing thus far, devices joined, left and re-registered via Workplace Join are currently not cleaned up within the ‘RegisteredDevices’ container. Some PowerShell scripting is currently required to enforce this. Later in this blog post we will explain you what we made available thru powershell.

This is question comes up all the time … how do I map a user to the devices that they have registered ?

1. The first attempt of Microsoft can be found here as this blog post is provided by Adam Hall . This is the output if you run the original script :

2. The second attempt to optimize the readout was done by a colleague Stijn Callebaut and it was already an improvement

The optimized code could be found below :

#user is provide by argument
if ($args.count -ne 1)
{        
    Write-Host "Usage: GetRegisteredDeviceForUser.ps1 <user name>"
    exit 1 
}

#get user's sid
$domain = Get-ADDomain
$userName = $args[0]
$userSid = (New-Object System.Security.Principal.NTAccount($domain.NetBIOSName, $userName)).Translate([System.Security.Principal.SecurityIdentifier]).value

#search device object when registeredUser = user sid
$objDefaultNC = New-Object System.DirectoryServices.DirectoryEntry

$ldapPath = "LDAP://CN=RegisteredDevices," + $objDefaultNC.distinguishedName 
$objDeviceContainer = New-Object System.DirectoryServices.DirectoryEntry($ldapPath)
$strFilter = "(&(objectClass=msDS-Device)(msDS-RegisteredOwner=$userSid))"

$objSearcher = New-Object System.DirectoryServices.DirectorySearcher
$objSearcher.SearchRoot = $objDeviceContainer 
$objSearcher.PageSize = 100
$objSearcher.Filter = $strFilter
$objSearcher.SearchScope = "Onelevel"
$colResults = $objSearcher.FindAll()

foreach ($objResult in $colResults){
    $props = @{
        cn=$objResult.Properties['cn']
        whencreated=$objResult.Properties['whencreated']
        whenchanged=$objResult.Properties['whenchanged']
        displayname=$objResult.Properties['displayname']
        }
    new-object PSObject -Property $props
            
}

3. But weren’t quite there yet. We wanted three things :

• Easy browsing and easily find devices registered to a user
• Easy selection of the devices needed
• Delete the devices properly

A colleague working with me on a project and good friend Kurt Depre , learned to use Powershell Xaml thru MVP Kaido Jarvemets for our customer project and said he would make a great interface for my issue. After some days of testing we finally can show you the result of our powershell tool.

The tool is called Workplace Join Hitman and can let you do easy searching for devices that are workplace joined by a single user and revoke access by deleting the object .

You can download it and please rate the tool if you like it. It’s downloadable on Technet Gallery here : http://gallery.technet.microsoft.com/WorkPlace-Join-Hitman-8c691238

It is not perfect , but it is intended to give you some idea’s to further automate the process when a device is stolen , lost or just discontinued. Next idea is to do that in a kind of Orchestrator workflow.

Hope it Helps , 

Kenny Buntinx

Enterprise Client Management MVP