140 lines
3.3 KiB
C#
140 lines
3.3 KiB
C#
#region Copyright & License Information
|
|
/*
|
|
* Copyright 2007-2020 The OpenRA Developers (see AUTHORS)
|
|
* This file is part of OpenRA, which is free software. It is made
|
|
* available to you under the terms of the GNU General Public License
|
|
* as published by the Free Software Foundation, either version 3 of
|
|
* the License, or (at your option) any later version. For more
|
|
* information, see COPYING.
|
|
*/
|
|
#endregion
|
|
|
|
using System;
|
|
using System.Collections.Generic;
|
|
using System.Linq;
|
|
using System.Net;
|
|
using System.Net.Sockets;
|
|
|
|
namespace OpenRA.Server
|
|
{
|
|
public class Connection
|
|
{
|
|
public const int MaxOrderLength = 131072;
|
|
|
|
public readonly Socket Socket;
|
|
public readonly List<byte> Data = new List<byte>();
|
|
public readonly int PlayerIndex;
|
|
public readonly string AuthToken;
|
|
|
|
public long TimeSinceLastResponse => Game.RunTime - lastReceivedTime;
|
|
public int MostRecentFrame { get; private set; }
|
|
|
|
public bool TimeoutMessageShown;
|
|
public bool Validated;
|
|
|
|
ReceiveState state = ReceiveState.Header;
|
|
int expectLength = 8;
|
|
int frame = 0;
|
|
long lastReceivedTime = 0;
|
|
|
|
public Connection(Socket socket, int playerIndex, string authToken)
|
|
{
|
|
Socket = socket;
|
|
PlayerIndex = playerIndex;
|
|
AuthToken = authToken;
|
|
}
|
|
|
|
public byte[] PopBytes(int n)
|
|
{
|
|
var result = Data.GetRange(0, n);
|
|
Data.RemoveRange(0, n);
|
|
return result.ToArray();
|
|
}
|
|
|
|
bool ReadDataInner(Server server)
|
|
{
|
|
var rx = new byte[1024];
|
|
var len = 0;
|
|
|
|
while (true)
|
|
{
|
|
try
|
|
{
|
|
// Poll the socket first to see if there's anything there.
|
|
// This avoids the exception with SocketErrorCode == `SocketError.WouldBlock` thrown
|
|
// from `socket.Receive(rx)`.
|
|
if (!Socket.Poll(0, SelectMode.SelectRead)) break;
|
|
|
|
if ((len = Socket.Receive(rx)) > 0)
|
|
Data.AddRange(rx.Take(len));
|
|
else
|
|
{
|
|
if (len == 0)
|
|
server.DropClient(this);
|
|
break;
|
|
}
|
|
}
|
|
catch (SocketException e)
|
|
{
|
|
// This should no longer be needed with the socket.Poll call above.
|
|
if (e.SocketErrorCode == SocketError.WouldBlock) break;
|
|
|
|
server.DropClient(this);
|
|
Log.Write("server", "Dropping client {0} because reading the data failed: {1}", PlayerIndex, e);
|
|
return false;
|
|
}
|
|
}
|
|
|
|
lastReceivedTime = Game.RunTime;
|
|
TimeoutMessageShown = false;
|
|
|
|
return true;
|
|
}
|
|
|
|
public void ReadData(Server server)
|
|
{
|
|
if (ReadDataInner(server))
|
|
{
|
|
while (Data.Count >= expectLength)
|
|
{
|
|
var bytes = PopBytes(expectLength);
|
|
switch (state)
|
|
{
|
|
case ReceiveState.Header:
|
|
{
|
|
expectLength = BitConverter.ToInt32(bytes, 0) - 4;
|
|
frame = BitConverter.ToInt32(bytes, 4);
|
|
state = ReceiveState.Data;
|
|
|
|
if (expectLength < 0 || expectLength > MaxOrderLength)
|
|
{
|
|
server.DropClient(this);
|
|
Log.Write("server", "Dropping client {0} for excessive order length = {1}", PlayerIndex, expectLength);
|
|
return;
|
|
}
|
|
|
|
break;
|
|
}
|
|
|
|
case ReceiveState.Data:
|
|
{
|
|
if (MostRecentFrame < frame)
|
|
MostRecentFrame = frame;
|
|
|
|
server.DispatchOrders(this, frame, bytes);
|
|
expectLength = 8;
|
|
state = ReceiveState.Header;
|
|
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
public EndPoint EndPoint => Socket.RemoteEndPoint;
|
|
}
|
|
|
|
public enum ReceiveState { Header, Data }
|
|
}
|