functions/ConvertFrom-AadBase64StringToThumbprint.ps1
<#
.SYNOPSIS Converts a Base64Encoded Thumbprint or also known as Key Identifier (Kid) back to its original Thumbprint value .DESCRIPTION Converts a Base64Encoded Thumbprint or also known as Key Identifier (Kid) back to its original Thumbprint value .PARAMETER Base64String Base64Encoded version of the Thumbprint .EXAMPLE ConvertFrom-AadBase64StringToThumbprint -Base64String 'z79RnGljTQa9Zh4ZjLq6UaB4eUM=' Output... CF-BF-51-9C-69-63-4D-06-BD-66-1E-19-8C-BA-BA-51-A0-78-79-43 .NOTES #> Function ConvertFrom-AadBase64StringToThumbprint { [cmdletbinding()] param( [parameter(Mandatory=$true, Position=0, ValueFromPipeline = $true)] [String] $Base64String ) while($Base64String.Length % 4 -ne 0) { $Base64String += "=" } $Bytes =[Convert]::FromBase64String($Base64String.Replace("-","+").Replace("_","/")) $Thumbprint = [BitConverter]::ToString($Bytes); return $Thumbprint } |