MSIdentityTools

2.0.1

internal/Invoke-CommandAsSystem.ps1

<#
.SYNOPSIS
    Run PowerShell commands under system context.
.EXAMPLE
    PS C:\>Invoke-CommandAsSystem { [System.Security.Principal.WindowsIdentity]::GetCurrent().Name }
    Run the ScriptBlock under the system context.
.INPUTS
    System.Management.Automation.ScriptBlock
.LINK
    https://github.com/jasoth/Utility.PS
#>
function Invoke-CommandAsSystem {
    [CmdletBinding()]
    param (
        #
        [Parameter(Mandatory = $true, ValueFromPipeline = $true, Position = 1)]
        [ScriptBlock] $ScriptBlock,
        #
        [Parameter(Mandatory = $false, Position = 2)]
        [string[]] $ArgumentList
    )

    begin {
        ## Initialize Critical Dependencies
        $CriticalError = $null
        try {
            Import-Module PSScheduledJob, ScheduledTasks -ErrorAction Stop
        }
        catch { Write-Error -ErrorRecord $_ -ErrorVariable CriticalError; return }
    }

    process {
        ## Return Immediately On Critical Error
        if ($CriticalError) { return }

        ## Process
        [guid] $GUID = New-Guid

        try {
            ## Register ScheduleJob
            if ($ArgumentList) {
                $ScheduledJob = Register-ScheduledJob -Name $GUID -ScheduledJobOption (New-ScheduledJobOption -RunElevated) -ScriptBlock $ScriptBlock -ArgumentList $ArgumentList -ErrorAction Stop
            }
            else {
                $ScheduledJob = Register-ScheduledJob -Name $GUID -ScheduledJobOption (New-ScheduledJobOption -RunElevated) -ScriptBlock $ScriptBlock -ErrorAction Stop
            }
            try {
                ## Register ScheduledTask for ScheduledJob
                $ScheduledTask = Register-ScheduledTask -TaskName $GUID -Action (New-ScheduledTaskAction -Execute $ScheduledJob.PSExecutionPath -Argument $ScheduledJob.PSExecutionArgs) -Principal (New-ScheduledTaskPrincipal -UserId 'NT AUTHORITY\SYSTEM' -LogonType ServiceAccount -RunLevel Highest) -ErrorAction Stop

                try {
                    ## Execute ScheduledTask Job to Run ScheduledJob Job
                    $ScheduledTask | Start-ScheduledTask -AsJob -ErrorAction Stop | Wait-Job | Remove-Job -Force -Confirm:$False

                    ## Wait for ScheduledTask to finish
                    While (($ScheduledTask | Get-ScheduledTaskInfo).LastTaskResult -eq 267009) { Start-Sleep -Milliseconds 150 }

                    ## Find ScheduledJob and get the result
                    $Job = Get-Job -Name $GUID -ErrorAction SilentlyContinue | Wait-Job
                    $Result = $Job | Receive-Job -Wait -AutoRemoveJob
                }
                finally {
                    ## Unregister ScheduledTask for ScheduledJob
                    $ScheduledTask | Unregister-ScheduledTask -Confirm:$false
                }
            }
            finally {
                ## Unregister ScheduleJob
                $ScheduledJob | Unregister-ScheduledJob -Force -Confirm:$False
            }
        }
        catch { Write-Error -ErrorRecord $_; return }

        return $Result
    }
}