void CreatePublicKey()
{
Diff = new DiffieHellman();
khoapublic = Diff.PublicKey;
keypublic = Convert.ToBase64String(khoapublic);
txtPublicKey.Text = keypublic;
}
static public byte SendMessage(String login, String message)
{
Socket socket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
try
{
socket.Connect(ipPoint);
BinaryWriter bw = new BinaryWriter(new NetworkStream(socket), Encoding.UTF8);
bw.Write(MESSAGE_CODE);
bw.Write(login);
BinaryReader br = new BinaryReader(new NetworkStream(socket));
BigInteger n = BigInteger.Parse(br.ReadString());
BigInteger q = BigInteger.Parse(br.ReadString());
BigInteger y = DiffieHellman.RandomPrimeBigInteger(n);
BigInteger K = BigInteger.ModPow(q, y, n);
bw.Write(K.ToString());
BigInteger M = BigInteger.Parse(br.ReadString());
BigInteger key = BigInteger.ModPow(M, y, n);
String encryptedMessage = DiffieHellman.encryptRS4(key.ToString(), message);
bw.Write(encryptedMessage);
byte[] answer = new byte[1];
socket.Receive(answer);
socket.Shutdown(SocketShutdown.Both);
socket.Close();
return(answer[0]);
}
catch (Exception ex) { return(MESSAGE_FAILED_CODE); }
}
void TaoKey()
{
Diff = new DiffieHellman();
khoapublic = Diff.PublicKey;
keypublic = Convert.ToBase64String(khoapublic);
textBox3.Text = keypublic;
}
public static BigInteger RandomPrimeBigInteger(BigInteger maxValue)
{
RandomNumberGenerator rng = RandomNumberGenerator.Create();
byte[] bytes = new byte[maxValue.ToByteArray().LongLength];
BigInteger result;
do
{
do
{
rng.GetBytes(bytes);
result = BigInteger.Abs(new BigInteger(bytes));
} while (result > maxValue);
} while (!DiffieHellman.IsProbablePrime(result, MILLER_RABIN_CERTAINTY));
return(result);
}