C# - 레지스트리에 등록된 마이크로소프트 제품의 DigitalProductId로부터 라이선스 키(Product Key)를 알아내는 방법

다음과 같은 글이 있군요. ^^

Decode DigitalProductId Registry Keys To Original Product Key with PowerShell
; https://chentiangemalc.wordpress.com/2021/02/23/decode-digitalproductid-registry-keys-to-original-product-key-with-powershell/

using Microsoft.Win32;
using RegUtils;
using System;
using System.Collections.Concurrent;
using System.Collections.Generic;
using System.Threading.Tasks;

class Program
{
    static void Main(string[] args)
    {
        RegistryFinder regFinder = new RegUtils.RegistryFinder();

        string searchTerm = "DigitalProductId";

        RegistryKey baseKey = Microsoft.Win32.RegistryKey.OpenBaseKey(Microsoft.Win32.RegistryHive.LocalMachine,
            Microsoft.Win32.RegistryView.Registry64);
        regFinder.FindRegValueNames(baseKey, searchTerm);

        foreach (KeyValuePair<string, string> result in regFinder.Results)
        {
            byte [] keyData = Registry.GetValue(result.Key, "DigitalProductId", null) as byte [];
            if (keyData == null)
            {
                Console.WriteLine(result.Key);
                continue;
            }

            Console.WriteLine($"{result.Key}: {DecodeKey(keyData)}");
        }
    }

    static string DecodeKey(byte[] key)
    {
        string KeyOutput = "";
        int KeyOffset = 52;

        if (key.Length < 66)
        {
            return "";
        }

        int dn = (int)System.Math.Truncate((double)key[66] / 6);
        bool isWin8 = (bool)((dn & 1) == 1);

        key[66] = (byte)((key[66] & 0xF7));
        int i = 24;
        string maps = "BCDFGHJKMPQRTVWXY2346789";

        int last = 0;
        do
        {
            int current = 0;
            int j = 14;
            do
            {
                current = current * 256;
                current = key[j + KeyOffset] + current;
                key[j + KeyOffset] = (byte)System.Math.Truncate((double)current / 24);
                current = current % 24;
                j--;
            } while (j >= 0);

            i--;
            KeyOutput = maps.Substring(current, 1) + KeyOutput;
            last = current;
        } while (i >= 0);

        if (isWin8 == true)
        {
            string keypart1 = KeyOutput.Substring(1, last);
            if (string.IsNullOrEmpty(keypart1) == true)
            {
                return "";
            }

            string insert = "N";
            KeyOutput = KeyOutput.Replace(keypart1, keypart1 + insert);
            if (last == 0)
            {
                KeyOutput = insert + KeyOutput;
            }
        }

        string result = "";

        if (KeyOutput.Length == 26)
        {
            result = string.Format("{0}-{1}-{2}-{3}-{4}",
                KeyOutput.Substring(1, 5),
                KeyOutput.Substring(6, 5),
                KeyOutput.Substring(11, 5),
                KeyOutput.Substring(16, 5),
                KeyOutput.Substring(21, 5));
        }
        else
        {
            Console.WriteLine(KeyOutput);
        }

        return result;
    }
}

namespace RegUtils
{
    public class RegistryFinder
    {
        public ConcurrentBag<KeyValuePair<string, string>> Results;

        public RegistryFinder()
        {
            Results = new ConcurrentBag<KeyValuePair<string, string>>();
        }

        public void FindRegValueNames(RegistryKey SubKey, string pattern)
        {
            FindRegValueNames(SubKey, pattern, true);
        }

        private void FindRegValueNames(RegistryKey SubKey, string pattern, bool first)
        {
            try
            {
                Parallel.ForEach(SubKey.GetSubKeyNames(), sub =>
                {
                    try
                    {
                        if (first)
                        {
                            foreach (var valueName in SubKey.GetValueNames())
                            {
                                if (string.Equals(valueName, pattern, StringComparison.OrdinalIgnoreCase) == true)
                                {
                                    Results.Add(new KeyValuePair<string, string>(SubKey.Name, valueName));
                                }
                            }
                        }

                        RegistryKey local = SubKey.OpenSubKey(sub);
                        foreach (var valueName in local.GetValueNames())
                        {
                            if (string.Equals(valueName, pattern, StringComparison.OrdinalIgnoreCase) == true)
                            {
                                Results.Add(new KeyValuePair<string, string>(local.Name, valueName));
                            }
                        }

                        FindRegValueNames(local, pattern, false);
                    }
                    catch (System.Security.SecurityException)
                    {
                    }
                });
            }
            catch { }
        }
    }
}

HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Microsoft\Microsoft SQL Server\150\Tools\ClientSetup:
HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Microsoft\Microsoft SQL Server\140\Tools\ClientSetup:
HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Microsoft\Microsoft SQL Server\130\Tools\ClientSetup:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\DefaultProductKey2: J5ANC-4J1BC-BDHV3-BDPH5-47JQT
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\DefaultProductKey: AGVTT-V0H53-2CCHJ-W4FW5-7HV9Q
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion: J5ANC-4J1BC-BDHV3-BDPH5-47JQT
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Microsoft SQL Server\MSSQL15.MSSQLSERVER\Setup:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Microsoft SQL Server\150\Tools\ClientSetup:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Internet Explorer\Registration: J5ANC-4J1BC-BDHV3-BDPH5-47JQT
HKEY_LOCAL_MACHINE\SYSTEM\Setup\Source OS (Updated on 6/14/2019 23:54:49): J5ANC-4J1BC-BDHV3-BDPH5-47JQT
HKEY_LOCAL_MACHINE\SYSTEM\Setup\Source OS (Updated on 6/11/2020 19:38:06): J5ANC-4J1BC-BDHV3-BDPH5-47JQT
HKEY_LOCAL_MACHINE\SYSTEM\Setup\Source OS (Updated on 5/2/2018 21:12:54): J5ANC-4J1BC-BDHV3-BDPH5-47JQT
HKEY_LOCAL_MACHINE\SYSTEM\Setup\Source OS (Updated on 2/15/2019 20:33:20): J5ANC-4J1BC-BDHV3-BDPH5-47JQT
HKEY_LOCAL_MACHINE\SYSTEM\Setup\Source OS (Updated on 11/20/2017 09:45:21): J5ANC-4J1BC-BDHV3-BDPH5-47JQT
HKEY_LOCAL_MACHINE\SYSTEM\Setup\Source OS (Updated on 11/11/2019 22:26:04): J5ANC-4J1BC-BDHV3-BDPH5-47JQT