Synnefo » Pithos MS Client

using System;

using System.Security.Cryptography;

namespace Hammock.Security.Cryptography

{

  public abstract class KeyedHashAlgorithm : HashAlgorithm

  {

    protected byte[] KeyValue;

    public virtual byte[] Key

    {

      get

      {

        return (byte[])this.KeyValue.Clone();

      }

      set

      {

        if (this.State != 0)

        {

          throw new CryptographicException("Key can't be changed at this state.");

        }

        this.ZeroizeKey();

        this.KeyValue = (byte[])value.Clone();

      }

    }

    ~KeyedHashAlgorithm()

    {

      this.Dispose(false);

    }

    protected override void Dispose(bool disposing)

    {

      this.ZeroizeKey();

      base.Dispose(disposing);

    }

    private void ZeroizeKey()

    {

      if (this.KeyValue != null)

        Array.Clear(this.KeyValue, 0, this.KeyValue.Length);

    }

    public static new KeyedHashAlgorithm Create()

    {

      return Create("System.Security.Cryptography.KeyedHashAlgorithm");

    }

    public static new KeyedHashAlgorithm Create(string algName)

    {

      return (KeyedHashAlgorithm)CryptoConfig.CreateFromName(algName);

    }

  }

}