/// <summary>
/// Client connected. Establish SSL, do handshake and validate client before accepting it.
/// </summary>
/// <param name="r"></param>
void ClientAccepted(IAsyncResult r)
{
// Continue listening
try
{
listener.BeginAcceptTcpClient(ClientAccepted, null);
}
catch (Exception ex)
{
if (IsListening)
{
Logger.Log($"Failed to continue listening... " + ex.GetDetailedMessage(), Logger.LogSeverity.Debug);
}
return;
}
// Start accepting client
var client = listener.EndAcceptTcpClient(r);
Logger.Log($"Client connecting from {client.Client.RemoteEndPoint}...", Logger.LogSeverity.Debug);
if (plugins?.Invoke(p => p.OnClientConnecting(client), true) == false)
{
// reject client
Logger.Log("Client rejected by plugin.", Logger.LogSeverity.Debug);
client.ProperlyClose();
return;
}
// Create client object
var wc = new WorkerClient(client);
// Start handshake
try
{
var stream = client.GetStream();
Logger.Log($"Establishing secure connection to {client.Client.RemoteEndPoint}...", Logger.LogSeverity.Debug);
// setup SSL here
var sslstream = SecurityUtils.ServerEstablishSSL(stream, certificate);
wc.MesssageHandler = new NetworkMessageHandler <NetworkMessage>(sslstream, m => ClientMessageReceived(wc, m));
wc.MesssageHandler.ExceptionThrown += (a, b) =>
{
wc.MesssageHandler.Dispose();
if (wc.Online)
{
wc.Online = false;
ClientLeft?.Invoke(wc, null);
Logger.Log($"Client disconnected from {wc.RemoteEndpoint}! ({wc.Id})");
// ignore certain common errors
if (!IgnoreError(b))
{
Logger.Log(b.GetDetailedMessage(), Logger.LogSeverity.Debug);
}
}
};
Logger.Log($"Validating {client.Client.RemoteEndPoint}...", Logger.LogSeverity.Debug);
wc.Id = SecurityUtils.DoHandshake(wc.MesssageHandler, passwordHash, false, null,
id => Clients.Count(x => x.Id == id) > 0,
id =>
{
var c = Clients.Where(x => x.Id == id).FirstOrDefault();
if (c == null)
{
return(false); // generate new Id if client doesn't exist
}
if (c.Online == true)
{
return(false); // worker already online with this Id, generate new Id
}
// worker with this Id is offline, assume this is that worker
return(true);
});
wc.HandshakeCompleted = true;
}
catch (Exception ex)
{
Logger.Log($"Rejected client from {wc.RemoteEndpoint}. " + ex.Message, Logger.LogSeverity.Warning);
Logger.Log(ex.GetDetailedMessage(), Logger.LogSeverity.Debug);
try
{
wc.MesssageHandler.SendMessage(new NetworkMessage(NetworkMessageType.Reject));
}
catch { }
client.ProperlyClose();
return;
}
wc.Online = true;
wc.LastConnected = DateTime.Now;
// try get existing client
var ewc = Clients.Where(x => x.Id == wc.Id).FirstOrDefault();
// Accept valid client
Logger.Log($"Accepted {(ewc == null ? "new" : "existing")} client from {client.Client.RemoteEndPoint}. ({wc.Id})");
lock (Clients)
{
// if client doesn't exist yet, add it - otherwise replace existing client
if (ewc == null)
{
Clients.Add(wc);
}
else
{
var index = Clients.IndexOf(ewc);
Clients[index] = wc;
}
}
plugins?.Invoke(p => p.OnClientConnect(wc.Client, wc.Id));
// send configuration
wc.MesssageHandler.SendMessage(new NetworkMessage(NetworkMessageType.ConfigUpdate, WorkerConfig));
// send client limit
wc.MesssageHandler.SendMessage(new NetworkMessage(
NetworkMessageType.WorkLimitUpdate, config.ClientWorkLimit));
ClientJoined?.Invoke(wc, ewc != null);
}
private void OnClientLeft(RailController client)
{
ClientLeft?.Invoke(client);
}