System.Security.Cryptography.PasswordDeriveBytes.GetBytes C# (CSharp) Method

	public override byte[] GetBytes (int cb) 
	{
#if NET_2_0
 #pragma warning restore 809
#else
		// 1.0/1.1 was a little late at throwing the argument exception ;-)
		if (password == null)
			throw new ArgumentNullException ("Password");
#endif
		if (cb < 1)
			throw new IndexOutOfRangeException ("cb");

		if (state == 0) {
			// it's now impossible to change the HashName, Salt
			// and IterationCount
			Reset ();
			state = 1;
		}

		byte[] result = new byte [cb];
		int cpos = 0;
		// the initial hash (in reset) + at least one iteration
		int iter = Math.Max (1, IterationsValue - 1);

		// start with the PKCS5 key
		if (output == null) {
			// calculate the PKCS5 key
			output = initial;

			// generate new key material
			for (int i = 0; i < iter - 1; i++)
				output = hash.ComputeHash (output);
		}

		while (cpos < cb) {
			byte[] output2 = null;
			if (hashnumber == 0) {
				// last iteration on output
				output2 = hash.ComputeHash (output);
			}
			else if (hashnumber < 1000) {
				string n = Convert.ToString (hashnumber);
				output2 = new byte [output.Length + n.Length];
				for (int j=0; j < n.Length; j++)
					output2 [j] = (byte)(n [j]);
				Buffer.BlockCopy (output, 0, output2, n.Length, output.Length);
				// don't update output
				output2 = hash.ComputeHash (output2);
			}
			else {
				throw new CryptographicException (
					Locale.GetText ("too long"));
			}

			int rem = output2.Length - position;
			int l = Math.Min (cb - cpos, rem);
			Buffer.BlockCopy (output2, position, result, cpos, l);
			cpos += l;
			position += l;
			while (position >= output2.Length) {
				position -= output2.Length;
				hashnumber++;
			}
		}
		return result;
	}

 protected static string DecryptString(string InputText, string Password)
 {
     try
     {
         RijndaelManaged RijndaelCipher = new RijndaelManaged();
         byte[] EncryptedData = Convert.FromBase64String(InputText);
         byte[] Salt = Encoding.ASCII.GetBytes(Password.Length.ToString());
         PasswordDeriveBytes SecretKey = new PasswordDeriveBytes(Password, Salt);
         // Create a decryptor from the existing SecretKey bytes.
         ICryptoTransform Decryptor = RijndaelCipher.CreateDecryptor(SecretKey.GetBytes(16), SecretKey.GetBytes(16));
         MemoryStream memoryStream = new MemoryStream(EncryptedData);
         // Create a CryptoStream. (always use Read mode for decryption).
         CryptoStream cryptoStream = new CryptoStream(memoryStream, Decryptor, CryptoStreamMode.Read);
         // Since at this point we don't know what the size of decrypted data
         // will be, allocate the buffer long enough to hold EncryptedData;
         // DecryptedData is never longer than EncryptedData.
         byte[] PlainText = new byte[EncryptedData.Length];
         // Start decrypting.
         int DecryptedCount = cryptoStream.Read(PlainText, 0, PlainText.Length);
         memoryStream.Close();
         cryptoStream.Close();
         // Convert decrypted data into a string.
         string DecryptedData = Encoding.Unicode.GetString(PlainText, 0, DecryptedCount);
         // Return decrypted string.
         return DecryptedData;
     }
     catch (Exception exception)
     {
         return (exception.Message);
     }
 }