//*********************************************************************
//
// UniqueKeyContainerName
// Derives unique key container name from CryptoAPI keycontainer name
//
// Note that keycontainer implementions are platform specific.
// 
//  Copyright (C) 2004.  Michel I. Gallant
//
//**********************************************************************


using System;
using System.IO;
using System.Text;
using System.Security;
using System.Security.Cryptography;
using Microsoft.Win32;


public class uniquekeycontainer {

 public static void Main(String[] args)
	{
	Console.WriteLine("Enter CryptoAPI CSP key containername:");
	string containername = Console.ReadLine().Trim().ToLower();

	byte[] strdata = Encoding.ASCII.GetBytes(containername);
	// uniquecontainername includes terminal null byte in data-to-hash; C# initializes array to zero
	byte[] datatohash = new byte[strdata.Length + 1];
	Array.Copy(strdata, datatohash, strdata.Length);

	MD5 md5 = new MD5CryptoServiceProvider();
	byte[] result = md5.ComputeHash(datatohash);
	showBytes("\nMD5 raw hash:", result) ;

	// Display as  DWORD (4-byte) groups; this simply reverses the order of 4-byte groups
	Console.WriteLine("Uniquecontainername prefix  (hash read as 4 DWORDS)");
	StringBuilder strb = new StringBuilder(32) ;
	BinaryReader binr = new BinaryReader(new MemoryStream(result)) ;
	for(int i=1; i<=4; i++)
	   strb.Append(binr.ReadInt32().ToString("x8"));  //read and build string
	Console.WriteLine("{0}", strb.ToString()) ;	

	// Get MachineGuid suffix form registry
	try{
         RegistryKey rk = Registry.LocalMachine.OpenSubKey("SOFTWARE\\Microsoft\\Cryptography");
         String mguid = (String)rk.GetValue("MachineGuid");
	 strb.Append("_" + mguid);
	 Console.WriteLine();
	 Console.WriteLine("Unique Key Container Name:\n{0}", strb.ToString());
	}
	catch(Exception exc)
	{
	 Console.WriteLine(exc.Message);
	}
	}



 private static byte[] GetFileBytes(String filename){
	if(!File.Exists(filename))
	 return null;
	Stream stream=new FileStream(filename,FileMode.Open);
	int datalen = (int)stream.Length;
	byte[] filebytes =new byte[datalen];
	stream.Seek(0,SeekOrigin.Begin);
	stream.Read(filebytes,0,datalen);
	stream.Close();
	return filebytes;
  }


  private static void showBytes(String info, byte[] data){
  Console.WriteLine("{0}  [{1} bytes]", info, data.Length);
  for(int i=1; i<=data.Length; i++){	
	Console.Write("{0:x2}", data[i-1]) ;
	if(i%16 == 0)
	 Console.WriteLine();
	}
  Console.WriteLine();
  }
 }