private async Task DataReceiver(ClientMetadata client)
{
Logger?.Invoke(_Header + "data receiver started for client " + client.IpPort, TCPLogType.Debug);
while (true)
{
try
{
if (client.Token.IsCancellationRequested ||
!IsClientConnected(client.Client))
{
Logger?.Invoke(_Header + "client " + client.IpPort + " disconnected", TCPLogType.Debug);
break;
}
if (client.Token.IsCancellationRequested)
{
Logger?.Invoke(_Header + "cancellation requested (data receiver for client " + client.IpPort + ")", TCPLogType.Debug);
break;
}
byte[] m_Buffer = await DataReadAsync(client);
if (m_Buffer == null)
{
await Task.Delay(30);
continue;
}
int BufferStart = 0;
int nBytesRec = m_Buffer.Length;
// We support the PROXY protocol (currently v1)
// PROXY TCP4 192.168.0.37 192.168.0.121 57307 16248\r\n
// PROXY TCP6 ffff:f...f:ffff ffff:f...f:ffff 65535 65535\r\n
// \x0D \x0A \x0D \x0A \x00 \x0D \x0A \x51 \x55 \x49 \x54 \x0A
// Min 32 bytes, max 108 bytes
if (nBytesRec > 32 && m_Buffer[0] == 'P' && m_Buffer[1] == 'R' && m_Buffer[2] == 'O' && m_Buffer[3] == 'X' && m_Buffer[4] == 'Y' && m_Buffer[5] == ' ')
{
try
{
string msg = Encoding.UTF8.GetString(m_Buffer, 0, Math.Min(108, nBytesRec)); // 108 is the max we need to parse
string[] proxy = msg.Split(new string[] { "\r\n" }, StringSplitOptions.RemoveEmptyEntries);
string[] proxyparts = proxy[0].Split(new string[] { " " }, StringSplitOptions.RemoveEmptyEntries);
client.OriginalIP = IPAddress.Parse(proxyparts[2]);
client.OriginalSrcPort = int.Parse(proxyparts[4]);
client.OriginalDestPort = int.Parse(proxyparts[5]);
client.IsProxied = true;
int split = msg.IndexOf("\r\n");
if (split > 32)
{
nBytesRec -= split + 2;
BufferStart = split + 2;
}
}
catch (Exception)
{
}
}
byte[] package = new byte[nBytesRec];
Buffer.BlockCopy(m_Buffer, BufferStart, package, 0, nBytesRec);
var args = new DataReceivedFromClientEventArgs(client.IpPort, package, client.IncomingProtocol, client.Client.Client.RemoteEndPoint);
args.Data = package;
args.Protocol = client.IncomingProtocol;
if (client.IsWebSocket)
{
args.WebSocketFrame = DecodeWebSocketMessage(package);
if (args.WebSocketFrame.OpCode == 0x9)
{
package[0] = (byte)((package[0] & 0xF0) + 0xA);
Send(client.IpPort, package);
return;
}
}
if (client.IsProxied)
{
args.OriginalIP = client.OriginalIP;
args.OriginalSrcPort = client.OriginalSrcPort;
args.OriginalDestPort = client.OriginalDestPort;
}
_Events.HandleDataReceived(this, args);
_Statistics.ReceivedBytes += package.Length;
UpdateClientLastSeen(client.IpPort);
}
catch (SocketException)
{
Logger?.Invoke(_Header + "data receiver socket exception (disconnection) for " + client.IpPort, TCPLogType.Debug);
}
catch (Exception e)
{
Logger?.Invoke(_Header + "data receiver exception for client " + client.IpPort + ":" +
Environment.NewLine +
e.ToString() +
Environment.NewLine, TCPLogType.Warn);
break;
}
}
Logger?.Invoke(_Header + "data receiver terminated for client " + client.IpPort, TCPLogType.Debug);
if (_ClientsKicked.ContainsKey(client.IpPort))
{
_Events.HandleClientDisconnected(this, new ClientDisconnectedEventArgs(client.IpPort, DisconnectReason.Kicked));
}
else if (_ClientsTimedout.ContainsKey(client.IpPort))
{
_Events.HandleClientDisconnected(this, new ClientDisconnectedEventArgs(client.IpPort, DisconnectReason.Timeout));
}
else
{
_Events.HandleClientDisconnected(this, new ClientDisconnectedEventArgs(client.IpPort, DisconnectReason.Normal));
}
DateTime removedTs;
_Clients.TryRemove(client.IpPort, out ClientMetadata destroyed);
_ClientsLastSeen.TryRemove(client.IpPort, out removedTs);
_ClientsKicked.TryRemove(client.IpPort, out removedTs);
_ClientsTimedout.TryRemove(client.IpPort, out removedTs);
client.Dispose();
}
internal void HandleDataReceived(object sender, DataReceivedFromClientEventArgs args)
{
DataReceived?.Invoke(sender, args);
}
