Powershell Script for RDP Services

The following test script (RDPServices.ps1) works on the RD-Connection Broker (Windows Server 2019-1809) with both Windows PowerShell (5.1) and Certify The Web (5.4.3) without any problems:

Import-Module RemoteDesktop

$Password = ConvertTo-SecureString -String “123” -AsPlainText -Force

Set-RDCertificate -Role RDWebAccess -ImportPath “C:\Program Files\CertifyTheWeb-Scripts\cert.pfx” -Password $Password -ConnectionBroker “srv.domain.at” -Force

On member servers, the script only works with Windows PowerShell.
With Certify The Web I get the following error message:

Screenshot 2021-06-14 183039

The authentication in the deployment task is Domain-Administrator,
the impersonation logon type is Batch.

Maybe someone has an idea how to solve this problem.

Thank you and best regards
Dietmar

Hi, have you tried other Logon Type options? I’ve found that different scripts behave differently and require different logon types depending on what they are actually trying to do.

Hello Christopher,
I think I found the cause.
Regardless of which authentication or which imperonation logon type is used, the script always runs as SYSTEM.
This works on the RD-Connection Broker, but not on the other servers.
What can I do so that the script runs as a domain administrator?

Thank you and best regards
Dietmar

Thanks Dietmar, the service does always run as SYSTEM but should be able to impersonate the user on the network in most instances, impersonation is complicated though, did you try both New Credentials and Network?

As a workaround, write a powershell script to write out the variable values that your script requires to another script, and call it from a (weekly etc) scheduled task, that way you will have complete control over the deployment scheduling and the user it runs as.

You can either write variables out as JSON to a file, then read them from your script, or write out a wrapper script which in turn calls the same script you are currently using.

Hello Christopher,
I have tested all 15 combinations of Authentication and Impersonation Logon Type - a Notepad started by the script is always executed as SYSTEM.

Am I correct in assuming that this shouldn’t be the case?
If so, are there any plans to resolve this issue in the near future?

Thank you and best regards
Dietmar

1 Like

Thanks, I’ll investigate this further.

We use the following library to implement our impersonation : GitHub - mattjohnsonpint/SimpleImpersonation: Simple Impersonation Library for .Net

There is some complexity/varied behaviour when impersonating within a thread vs spawning a new process and vs network access, made more complex because we host PowerShell within our process rather than launching a new powershell command line instance (which could be the solution).

I should add that there is a difference between impersonation and processes. notepad.exe is an interactive desktop session process so won’t be supported.

Here is a powershell script which should show the identity impersonation in effect:

param($result)


$result.ManagedItem.CertificatePath

$env:UserName

[System.Security.Principal.WindowsIdentity]::GetCurrent().Name

Running that script will show results in the log, and you can see that the environment loaded is still the primary users, but the windows identity is the impersonated user.

That doesn’t explain why your networked script doesn’t work, but it does demonstrate the basic impersonation.

As a follow up to this, I am working on an alternative option for both powershell scripts and .bat etc which just lets you launch a new process (we currently impersonate in-process). This takes care of subsequent spawned processes being under the correct user etc. Many script don’t need this, but some clearly do.

Hello Christopher,
Thank you for planning an alternative option for Powershell scripts, which ensures that subsequently generated processes run under the correct user.
Can you already let me know when this feature will be available?

Thank you and
best regards Dietmar

Hi Dietmar, this features is currently under development & testing and is planned for the next release. Releases are just done when all the targeted features and testing is complete but it’s expected next week or the week after.

Hello Christopher,

with version 5.5.2.0, the following script on the RD connection broker works fine with both Windows PowerShell and Certify The Web:

Import-Module RemoteDesktop
$Password = ConvertTo-SecureString -String “Ab123456” -AsPlainText -Force
Set-RDCertificate -Role RDRedirector -ImportPath “C:\Program Files\CertifyTheWeb-Scripts\wildcard.pfx” -Password $Password -ConnectionBroker “srv.domain.at” -Force
Set-RDCertificate -Role RDPublishing -ImportPath “C:\Program Files\CertifyTheWeb-Scripts\wildcard.pfx” -Password $Password -ConnectionBroker “srv.domain.at” -Force
Set-RDCertificate -Role RDWebAccess -ImportPath “C:\Program Files\CertifyTheWeb-Scripts\wildcard.pfx” -Password $Password -ConnectionBroker “srv.domain.at” -Force
Set-RDCertificate -Role RDGateway -ImportPath “C:\Program Files\CertifyTheWeb-Scripts\wildcard.pfx” -Password $Password -ConnectionBroker “srv.domain.at” -Force

On member servers, the script only works with Windows PowerShell.
With Certify The Web I get the following error message for RDWebAccess and RDGateway:

The authentication in the deployment task is Domain-Administrator,
the impersonation logon type is Batch.

Do you have any idea what might be causing this?

Thank you and
best regards Dietmar

Addition: With the new option “Launch New Process” I get the following error messages:

2021-07-25 15:43:15.603 +02:00 [INF] ---- Performing Task [On-Demand or Manual Execution] :: Run Powershell Script ----
2021-07-25 15:43:15.604 +02:00 [INF] Task [Run Powershell Script] :: Task is being has been forced to run. Normal status would be [Task is enabled but will not run because primary request unsuccessful.]
2021-07-25 15:43:15.605 +02:00 [INF] Executing command via PowerShell
2021-07-25 15:43:15.606 +02:00 [ERR] Launching Process C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe as User: DOMAIN\Administrator
Error Running Script: System.ComponentModel.Win32Exception (0x80004005): Zugriff verweigert
bei System.Diagnostics.Process.StartWithCreateProcess(ProcessStartInfo startInfo)
bei Certify.Management.PowerShellManager.ExecutePowershellAsProcess(CertificateRequestResult result, String executionPolicy, String scriptFile, Dictionary2 parameters, Dictionary2 credentials, String scriptContent, PowerShell shell, Boolean autoConvertBoolean, String[] ignoredCommandExceptions, Int32 timeoutMinutes) in D:\a\certify-service\certify-service\src\certify-build\certify\src\Certify.Shared.Compat\PowerShellManager.cs:Zeile 270.
Error: System.InvalidOperationException: Diesem Objekt ist kein Prozess zugeordnet.
bei System.Diagnostics.Process.EnsureState(State state)
bei System.Diagnostics.Process.get_HasExited()
bei Certify.Management.PowerShellManager.ExecutePowershellAsProcess(CertificateRequestResult result, String executionPolicy, String scriptFile, Dictionary2 parameters, Dictionary2 credentials, String scriptContent, PowerShell shell, Boolean autoConvertBoolean, String[] ignoredCommandExceptions, Int32 timeoutMinutes) in D:\a\certify-service\certify-service\src\certify-build\certify\src\Certify.Shared.Compat\PowerShellManager.cs:Zeile 283.

best regards Dietmar

Thanks, I’ll be investigating the new issue with starting powershell as a new process over the next couple days and if we get a fix it’ll be in the next update.