Documenting with PowerShell: Chapter 2 – Documenting Bitlocker keys

Our RMM system currently does not have support to securely store the bitlocker key inside of the RMM system itself. I’ve subscribed to the school of bitlocking everything that passes through my company, So also computers that sometimes never get connected to Azure AD, Active Directory to store the key in. We also get users that lost the USB drive or piece of paper that the key was stored on.

As we use a documentation system (IT-Glue) to store all our passwords, I figured why not try to also store our Bitlocker keys there, while tagging the device too so we can always find which device belongs to which key easily.

First for the none IT-Glue users I’ll generate a HTML file. With some small adaptation you can upload this to Confluence, ITBoost, or any other system you use. After that example, we’ll get onto IT-Glue again. So let’s get started!

Base script

The base script is the part of the script that captures the data that we want. In our case This will be the Bitlocker key, and output it an HTML file in C:\Temp\Temp.html You can use this script however you’d like.

$BitlockVolumes = Get-BitLockerVolume
#Some HTML to make the page pretty.
$head = @"
<script>
function myFunction() {
    const filter = document.querySelector('#myInput').value.toUpperCase();
    const trs = document.querySelectorAll('table tr:not(.header)');
    trs.forEach(tr => tr.style.display = [...tr.children].find(td => td.innerHTML.toUpperCase().includes(filter)) ? '' : 'none');
  }</script>
<title>Audit Log Report</title>
<style>
body { background-color:#E5E4E2;
      font-family:Monospace;
      font-size:10pt; }
td, th { border:0px solid black; 
        border-collapse:collapse;
        white-space:pre; }
th { color:white;
    background-color:black; }
table, tr, td, th {
     padding: 2px; 
     margin: 0px;
     white-space:pre; }
tr:nth-child(odd) {background-color: lightgray}
table { width:95%;margin-left:5px; margin-bottom:20px; }
h2 {
font-family:Tahoma;
color:#6D7B8D;
}
.footer 
{ color:green; 
 margin-left:10px; 
 font-family:Tahoma;
 font-size:8pt;
 font-style:italic;
}
#myInput {
  background-image: url('https://www.w3schools.com/css/searchicon.png'); /* Add a search icon to input */
  background-position: 10px 12px; /* Position the search icon */
  background-repeat: no-repeat; /* Do not repeat the icon image */
  width: 50%; /* Full-width */
  font-size: 16px; /* Increase font-size */
  padding: 12px 20px 12px 40px; /* Add some padding */
  border: 1px solid #ddd; /* Add a grey border */
  margin-bottom: 12px; /* Add some space below the input */
}
</style>
"@

foreach($BitlockVolume in $BitlockVolumes) {
$HTMLTop = @"
    <h1>Bitlocker Information</h1>
    <b>Computername: </b>$($BitlockVolume.ComputerName)<br>
    <b>Encryption Method:</b>$($BitlockVolume.EncryptionMethod)<br>
    <b>Volume Type:</b>$($BitlockVolume.VolumeType)<br>
    <b>Volume Status:</b>$($BitlockVolume.VolumeStatus)<br>
"@
$HTML += $BitlockVolume.KeyProtector | convertto-html -Head $head -PreContent "$HTMLTop <br> <h1>Keys for $($ENV:COMPUTERNAME) - $($BitlockVolume.Mountpoint)</h1>"
}
$html | Out-File C:\Temp\temp.html

Now, that’s cool. This gives us a good ol’ HTML file. We now have a choice, use the previous script found here and adapt it to upload it to IT-Glue as a Flexible Asset or make the choice to upload it as an embedded password and tag the correct device. That sounds cooler to me!

This script looks for a configuration in your IT-Glue database based on the computer’s serial number. If it finds a match it uploads the bitlocker key as an embedded password, with the name “COMPUTERNAME – DRIVE:” as an example for my computer “DESKTOP-U3984 – C:” – We do this because the hostname might change over time and you’d want the keys to be uploaded separately.

IT-Glue script

#####################################################################
$APIKEy =  "APIKEYHERE"
$APIEndpoint = "https://api.eu.itglue.com"
$orgID = "ORGIDHERE"
#####################################################################
#Grabbing ITGlue Module and installing,etc
If(Get-Module -ListAvailable -Name "ITGlueAPI") {Import-module ITGlueAPI} Else { install-module ITGlueAPI -Force; import-module ITGlueAPI}
#Settings IT-Glue logon information
Add-ITGlueBaseURI -base_uri $APIEndpoint
Add-ITGlueAPIKey $APIKEy
#This is the data we'll be sending to IT-Glue. 
$BitlockVolumes = Get-BitLockerVolume
#The script uses the following line to find the correct asset by serialnumber, match it, and connect it if found. Don't want it to tag at all? Comment it out by adding #
$TaggedResource = (Get-ITGlueConfigurations -organization_id $orgID -filter_serial_number (get-ciminstance win32_bios).serialnumber).data
foreach($BitlockVolume in $BitlockVolumes) {
$PasswordObjectName = "$($Env:COMPUTERNAME) - $($BitlockVolume.MountPoint)"
$PasswordObject = @{
    type = 'passwords'
    attributes = @{
            name = $PasswordObjectName
            password = $BitlockVolume.KeyProtector.recoverypassword[1]
            notes = "Bitlocker key for $($Env:COMPUTERNAME)"

    }
}
if($TaggedResource){ 
    $Passwordobject.attributes.Add("resource_id",$TaggedResource.Id)
    $Passwordobject.attributes.Add("resource_type","Configuration")
}

#Now we'll check if it already exists, if not. We'll create a new one.
$ExistingPasswordAsset = (Get-ITGluePasswords -filter_organization_id $orgID -filter_name $PasswordObjectName).data
#If the Asset does not exist, we edit the body to be in the form of a new asset, if not, we just upload.
if(!$ExistingPasswordAsset){
Write-Host "Creating new Bitlocker Password" -ForegroundColor yellow
$ITGNewPassword = New-ITGluePasswords -organization_id $orgID -data $PasswordObject
} else {
Write-Host "Updating Bitlocker Password" -ForegroundColor Yellow
$ITGNewPassword = Set-ITGluePasswords -id $ExistingPasswordAsset.id -data $PasswordObject
}
}

This script can also be found as an AMP file here, that’s it! as always, happy PowerShelling!

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Kelvin Tegelaar

I am a Microsoft Certified System Engineer working as the CTO of the Managed Services Provider Lime Networks B.V. in the Netherlands. I mostly enjoy automating business processes by deploying PowerShell solutions, but just have a large passion for Microsoft Technology in general.

If you want to contact me directly you can find me on twitter here, or via email: Kelvin {at} limenetworks.nl
Kelvin Tegelaar
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