private void ReceiveResponseFromServerAsync()
{
Task.Factory.StartNew(() =>
{
while (true)
{
int messageType;
try
{
messageType = BitConverter.ToInt32(connection.Receive(4), 0);
}
catch (IOException e)
{
Invoke((MethodInvoker) delegate
{
toggleLoginForm(false);
blocknote.Visible = false;
getSessionKeyButton.Enabled = true;
serverResponses.Visible = true;
serverResponses.Text = "session has been expired";
});
break;
}
var lenBytes = BitConverter.ToInt32(connection.Receive(4), 0);
Invoke((MethodInvoker) delegate
{
serverResponses.Visible = false;
});
byte[] msg = connection.Receive(lenBytes);
if (messageType == TCPConnection.ENCRYPTED_AES_WITH_RSA)
{
sessionAESKey = new byte[128];
Array.Copy(msg, 0, sessionAESKey, 0, 128);
sessionAESKey = keyPair.Decrypt(sessionAESKey);
sessionAESIV = new byte[128];
Array.Copy(msg, 128, sessionAESIV, 0, 128);
sessionAESIV = keyPair.Decrypt(sessionAESIV);
Invoke((MethodInvoker) delegate
{
getSessionKeyButton.Enabled = false;
});
}
else if (messageType == TCPConnection.LOGIN_APPROVED)
{
Invoke((MethodInvoker) delegate
{
toggleLoginForm(false);
loginRejected.Visible = false;
blocknote.Visible = true;
});
}
else if (messageType == TCPConnection.LOGIN_REJECTED)
{
Invoke((MethodInvoker) delegate
{
toggleLoginForm(true);
loginRejected.Visible = true;
});
}
else if (messageType == TCPConnection.TEXT)
{
var text = Encoding.UTF8.GetString(AES.Decrypt(msg, sessionAESKey, sessionAESIV));
Invoke((MethodInvoker) delegate
{
textBox1.Text = text;
});
}
else if (messageType == TCPConnection.FILE_DO_NOT_EXISTS)
{
Invoke((MethodInvoker) delegate
{
serverResponses.Visible = true;
serverResponses.Text = "file with such a filename does not exist";
});
}
else if (messageType == TCPConnection.FILE_SAVED)
{
Invoke((MethodInvoker) delegate
{
serverResponses.Visible = true;
serverResponses.Text = "file was saved";
});
}
else
{
break;
}
}
});
}
