Convert-SDDL.ps1

$VarD=$null
$VarS=$null
$ResultsD=$null
$ResultsS=$null
$Service="mslldp"
$AddPermissions="(A;;CCLCSWLOCRRC;;;SU)"
$VarAccount="SU"
[string]$RawResults=sc.exe sdshow $Service
$RegexPatternALL='(D:)(\(.*\))(S:)(\(.*\))|(S:)(\(.*\))|(D:)(\(.*\))'

# Match 0 is the complete string
# Match 1 is the D: label if both sections are present
# Match 2 is the D: section permissions if both sections are present
# Match 3 is the S: label if both sections are present
# Match 4 is the S: section permissions if both sections are present
# Match 5 is the S: label if only the S: section is present
# Match 6 is the S: section permissions if only the S: section is present
# Match 7 is the D: label if only the D: section is present
# Match 8 is the D: section permissions if only the D: section is present

$RawResults -match $RegexPatternALL | out-null
#$Matches
# Find the D: section
if ($null -eq $matches[1]){
    $VarD=$Matches[8]
}
else {
    $VarD=$Matches[2]
}

#Find the S: section
if ($null -eq $Matches[3]) {
    $VarS=$Matches[6]
}
else {
    $VarS=$Matches[4]
}

# Split the results into individual items then strip out the open and close parenthesis from all objects.
if ($null -ne $VarD){
    [array]$ResultsD=$VarD -split '\)\(' | foreach-object {$_ -replace "\(", ""} | foreach-object {$_ -replace "\)", ""}
}
if ($null -ne $VarS){
    [array]$ResultsS=$VarS -split '\)\(' | foreach-object {$_ -replace "\(", ""} | foreach-object {$_ -replace "\)", ""}
}

write-output "`nD:"
$ResultsD

write-output "`nS:"
$ResultsS

# Build new SD permission string so to confirm if the values are parsed correctly.
$ExistingPermissions=$null
if ($null -ne $ResultsD){
    # This is the first element in the array
    $ExistingPermissions=$ExistingPermissions + "D:"
    for ($i=0; $i -lt $ResultsD.count; $i++) {
        $ExistingPermissions=$ExistingPermissions + "(" + $ResultsD[$i] + ")"
    }
}
if ($null -ne $ResultsS){
    $ExistingPermissions=$ExistingPermissions + "S:"
    for ($i=0; $i -lt $ResultsS.count; $i++) {
        $ExistingPermissions=$ExistingPermissions + "(" + $ResultsS[$i] + ")"
    }
}
write-output "`nParsed permissions:"
$ExistingPermissions
write-output "`nOriginal permissions:"
$RawResults.trim()
# Compare the newly build results with the original results (trimming whitespace).
# Only add the new permissions if we could properly build a string with the existing data which matched the original permission string.
if ($ExistingPermissions -eq $RawResults.trim()) {
    Write-Output "`nCorrectly identified existing permissions."
    # Make sure that the permissions we are setting are not already in the existing permission string.
    if ($ExistingPermissions -notmatch $VarAccount){
        write-output "`nBuilding new permissions string..."
        $NewPermissions=$null
        if ($null -ne $ResultsD){
            # This is the first element in the array
            $NewPermissions=$NewPermissions + "D:"
            for ($i=0; $i -lt $ResultsD.count; $i++) {
                $NewPermissions=$NewPermissions + "(" + $ResultsD[$i] + ")"
            }
            $NewPermissions=$NewPermissions + $AddPermissions
        }
        if ($null -ne $ResultsS){
            $NewPermissions=$NewPermissions + "S:"
            for ($i=0; $i -lt $ResultsS.count; $i++) {
                $NewPermissions=$NewPermissions + "(" + $ResultsS[$i] + ")"
            }
        }
        write-output "`nNew permissions string will be:"
        $NewPermissions
        # sc.exe sdset $service $NewPermissions
    }
    else {
        write-output "Permissions for this account already exist. Please review."
        exit 1
    }

}
else {
    write-output "`nUnable to properly parse the permission results. Please review."
    exit 1
}