using System;
using System.Collections;
using Microsoft.Win32;
namespace MSKeyFinder
{
public class KeyDecoder
{
public enum Key { XP, Office10, Office11 };
public static byte[] GetRegistryDigitalProductId(Key key)
{
byte[] digitalProductId = null;
RegistryKey registry = null;
switch(key)
{
// Open the XP subkey readonly.
case Key.XP:
registry =
Registry.LocalMachine.
OpenSubKey(
@"SOFTWARE\Microsoft\Windows NT\CurrentVersion",
false);
break;
// Open the Office 10 subkey readonly.
case Key.Office10:
// TODO: Open the registry key.
break;
// Open the Office 11 subkey readonly.
case Key.Office11:
// TODO: Open the registry key.
break;
}
if(registry != null)
{
// TODO: For other products, key name maybe different.
digitalProductId = registry.GetValue("DigitalProductId")
as byte[];
registry.Close();
}
return digitalProductId;
}
public static string DecodeProductKey(byte[] digitalProductId)
{
// Offset of first byte of encoded product key in
// 'DigitalProductIdxxx" REG_BINARY value. Offset = 34H.
const int keyStartIndex = 52;
// Offset of last byte of encoded product key in
// 'DigitalProductIdxxx" REG_BINARY value. Offset = 43H.
const int keyEndIndex = keyStartIndex + 15;
// Possible alpha-numeric characters in product key.
char[] digits = new char[]
{
'B', 'C', 'D', 'F', 'G', 'H', 'J', 'K', 'M', 'P', 'Q', 'R',
'T', 'V', 'W', 'X', 'Y', '2', '3', '4', '6', '7', '8', '9',
};
// Length of decoded product key
const int decodeLength = 29;
// Length of decoded product key in byte-form.
// Each byte represents 2 chars.
const int decodeStringLength = 15;
// Array of containing the decoded product key.
char[] decodedChars = new char[decodeLength];
// Extract byte 52 to 67 inclusive.
ArrayList hexPid = new ArrayList();
for (int i = keyStartIndex; i <= keyEndIndex; i++)
{
hexPid.Add(digitalProductId[i]);
}
for (int i = decodeLength - 1; i >= 0; i--)
{
// Every sixth char is a separator.
if ((i + 1) % 6 == 0)
{
decodedChars[i] = '-';
}
else
{
// Do the actual decoding.
int digitMapIndex = 0;
for (int j = decodeStringLength - 1; j >= 0; j--)
{
int byteValue = (digitMapIndex << 8) | (byte)hexPid[j];
hexPid[j] = (byte)(byteValue / 24);
digitMapIndex = byteValue % 24;
decodedChars[i] = digits[digitMapIndex];
}
}
}
return new string(decodedChars);
}
}
}