PowerShell – Active Directory – Convert AD Name Formats

Many of the ActiveDirectory PowerShell module cmdlets expect the distinguished name format. I find this somewhat inconvenient, as this format does not read as nicely as the canonical name format that so many of us have become familiar with. Additionally, an objects’ canonical name is somewhat more readily available via the Active Directory Users and Computers (ADUC) GUI, by navigating to the ‘Objects’ tab. The distinguished name can be found under the Attribute Editor tab, which requires that you have Advanced Features enabled, have navigated to the object directly rather than with search, and then scroll through the list of Attributes.

I wanted the ability to be able to pass an object or container’s canonical name as input, but the cmdlets expect the distinguished name format. So, I put a function together that can convert either format into the other.

Here is the GitHub link: https://github.com/p8nflnt/SysAdmin-Toolbox/blob/main/Convert-AdName.ps1

And here is the script:

<#
.SYNOPSIS
    Convert canonical name to distinguished name format or vice versa.

.NOTES
    Name: Convert-AdName
    Author: Payton Flint
    Version: 1.0
    DateCreated: 2023-Dec

.LINK
    https://github.com/p8nflnt/SysAdmin-Toolbox/edit/main/Convert-AdName.ps1
    
PowerShell – Active Directory – Convert AD Name Formats

#>

Function Convert-ADName {
    param (
        $name,
        $nameType
    )
    # check name formatting
    if ($name -like '*.*' -or $name -like '*/*' -or $name -like '*=*') {

        # Check if the input is a canonical name format
        if ($name -match "(^CN=.*|^OU=.*|^DC=.*)") {

            # replace characters for reformatting
            $processedCN = $name -replace ',', '' -replace 'DC=', '.' -replace 'OU=', '/' -replace 'CN=', ''

            # drop leading '/' if present
            if ($processedCN -match "^/.*") {
                $processedCN = ($processedCN -split '\/', 2)[1]
            }

            # split canonical name in 2 parts at first '.'
            $splitCN = $processedCN -split '\.', 2

            # domain portion of canonical name
            $domain = $splitCN[1]

            # get remaining portion of canonical name if not empty
            if ($($splitCN[0]) -ne '') {

                # split remaining portion by '/' character
                $splitRemainder = $($splitCN[0]) -split '/'

                # invert order of the remaining items array
                $reversedRemainder = $splitRemainder[($splitRemainder.Length-1)..0]

                # reassemble in canonical name format for output
                $output = $domain + '/' + ($reversedRemainder -join '/')

            # if remainder is empty, list domain
            } else {
                $output = $domain 
            }
        # if input is distinguished name format
        } else {
        
            # alert user to provide input type
            if ($nameType -ne 'container' -and $nameType -ne 'object') {
                Write-Host -ForegroundColor Red "Distinguished name format detected.`r`n-inputType must be set to 'Container' or 'Object'."
            }

            # glitch in replace, had to invoke method this way
            # replace characters for reformatting
            $processedDN = $($name -replace '/', ',OU=').Replace('.', ',DC=')

            # if 'OU=' is present
            if ($processedDN -match ".*OU=.*") {

                # split in 2 parts at first ',OU='
                $splitDN = $processedDN -split '\,OU=', 2

                # domain portion of distinguished name
                $domain = $splitDN[0]

                # split remaining portion by ',OU='
                $splitRemainder = $($splitDN[1]) -split ',OU='

                # invert order of the remaining items array
                $reversedRemainder = $splitRemainder[($splitRemainder.Length-1)..0]

                # reassemble in distinguished name format for output
                $reassembledDN = ($reversedRemainder -join ',OU=') + ',DC=' + $domain

                # add appropriate prefix to distinguished name and output
                if ($nameType -eq 'object') {
                    $output = 'CN=' + $reassembledDN
                } elseif ($nameType -eq 'container' ) {
                    $output = 'OU=' + $reassembledDN
                }

            # if remainder is empty, list domain
            } else {
                $output = 'DC=' + $processedDN
            }
        }
    return $output
    # warn on invalid name format
    } else {
        Write-Host -ForegroundColor Red "Invalid name format."
    }
} # end Convert-ADName function


# variables
$distinguishedName = "entity.domain.org/Test/Computers/TEST-SYS1"

$canonicalName = "CN=TEST-SYS1,OU=Computers,OU=TEST,DC=entity,DC=domain,DC=org"

$nameType = 'object' # 'container'


# example use
$output = Convert-ADName -name $distinguishedName -nameType $nameType

$output