private void DisableEncryptionInterface(string text)
{
if (this.richMessage.InvokeRequired)
{
SetTextCallback d = new SetTextCallback(DisableEncryptionInterface);
this.Invoke(d, new object[] { text });
}
else
{
crypter = null;
isPublicSertificateSent = false;
btnEncrypt.Image = Resources.lock_open;
AddMessageToRichChat("=========================================" + Environment.NewLine);
AddMessageToRichChat("System: Encryption has been disabled" + Environment.NewLine);
toolTip1.SetToolTip(btnEncrypt, "Enable Secured Mode");
btnEncrypt.Enabled = true;
}
}
private void btnEncrypt_Click(object sender, EventArgs e)
{
btnEncrypt.Enabled = false;
if (crypter == null)
{
btnEncrypt.Image = Resources._lock;
AddMessageToRichChat("System: Initializing encryption procedure" + Environment.NewLine);
AddMessageToRichChat("System: Creating RSA-2048 certificates" + Environment.NewLine);
crypter = new RSACrypter();
AddMessageToRichChat("System: The public certificate has been sent to the partner" + Environment.NewLine);
SendMessage("$PUBLICKEY$" + crypter.PublicKey);
isPublicSertificateSent = true;
toolTip1.SetToolTip(btnEncrypt, "Disable Secured Mode");
btnEncrypt.Enabled = true;
}
else
{
SendMessage("$DISENCRYPT$", true);
DisableEncryptionInterface(null);
}
}
void DoListen()
{
AddMessageToRichChat("System: Connecting..." + Environment.NewLine);
if (isServer)
{
client = listener.AcceptTcpClient();
}
NetworkStream netStream = client.GetStream();
AddMessageToRichChat("System: Connection established" + Environment.NewLine);
EnableInterface(null);
while (true)
{
if (netStream.CanRead)
{
int numberOfBytesRead = 0;
string str = "";
try
{
numberOfBytesRead = netStream.Read(myReadBuffer, 0, myReadBuffer.Length);
str += Encoding.Unicode.GetString(myReadBuffer, 0, numberOfBytesRead);
if (str.Contains("$PUBLICKEY$"))
{
if (crypter == null)
{
crypter = new RSACrypter();
}
crypter.ThirdPartyPublicKey = str.Replace("$PUBLICKEY$", "");
AddMessageToRichChat("System: The partner's public certificate has been accepted" + Environment.NewLine);
if (!isPublicSertificateSent)
{
AddMessageToRichChat("System: Creating RSA-2048 certificates" + Environment.NewLine);
AddMessageToRichChat("System: The public certificate has been sent to the partner" + Environment.NewLine);
SendMessage("$PUBLICKEY$" + crypter.PublicKey);
EnableEncryptionInterface(null);
}
AddMessageToRichChat("=========================================" + Environment.NewLine);
AddMessageToRichChat("System: Secure connection successfully established" + Environment.NewLine);
continue;
}
if (crypter == null)
{
AddMessageToRichChat("Partner: " + str + Environment.NewLine);
}
else
{
byte[] encrypted_buffer = new byte[numberOfBytesRead];
for (int i = 0; i < numberOfBytesRead; i++)
{
encrypted_buffer[i] = myReadBuffer[i];
}
string message = crypter.decryptMessage(encrypted_buffer);
if (!message.Contains("$DISENCRYPT$"))
{
AddMessageToRichChat("Partner: " + message + Environment.NewLine);
}
else
{
DisableEncryptionInterface(null);
}
}
}
catch (Exception ex)
{
netStream.Close();
AddMessageToRichChat("System: Partner disconnected. Reason: " + ex.Message + Environment.NewLine);
DisableInterface(null);
break;
}
}
else
{
MessageBox.Show("Can`t read data!");
}
}
}