public override void AddToken(IPEndPoint endPoint, uint token)
{
TokenCache.AddToken(endPoint, token, TokenFlags.None);
}
public override bool Receive(ref Chunk packet, ref uint responseToken)
{
// TODO make multithreaded
// https://docs.microsoft.com/ru-ru/dotnet/standard/io/how-to-use-named-pipes-for-network-interprocess-communication
// https://blogs.msdn.microsoft.com/dotnet/2018/07/09/system-io-pipelines-high-performance-io-in-net/
while (true)
{
if (ChunkReceiver.FetchChunk(ref packet))
{
return(true);
}
if (UdpClient.Available <= 0)
{
return(false);
}
var endPoint = default(IPEndPoint);
byte[] data;
try
{
data = UdpClient.Receive(ref endPoint);
}
catch
{
continue;
}
if (data.Length == 0)
{
continue;
}
if (!NetworkHelper.UnpackPacket(data, data.Length, ChunkReceiver.ChunkConstruct))
{
continue;
}
if (NetworkBan.IsBanned(endPoint, out var banReason))
{
NetworkHelper.SendConnectionMsg(UdpClient, endPoint,
ChunkReceiver.ChunkConstruct.ResponseToken, 0, ConnectionMessages.Close, banReason);
continue;
}
var freeSlot = -1;
var foundSlot = -1;
var sameIps = 0;
for (var i = 0; i < Connections.Count; i++)
{
if (Connections[i].State == ConnectionState.Offline && freeSlot < 0)
{
freeSlot = i;
}
if (Connections[i].State != ConnectionState.Offline &&
Connections[i].EndPoint.Compare(endPoint, comparePorts: false))
{
sameIps++;
if (Connections[i].EndPoint.Port != endPoint.Port)
{
continue;
}
if (Connections[i].Feed(ChunkReceiver.ChunkConstruct, endPoint))
{
if (ChunkReceiver.ChunkConstruct.DataSize > 0)
{
if (ChunkReceiver.ChunkConstruct.Flags.HasFlag(PacketFlags.Connless))
{
packet = new Chunk()
{
Flags = SendFlags.Connless,
EndPoint = endPoint,
ClientId = i,
DataSize = ChunkReceiver.ChunkConstruct.DataSize,
Data = ChunkReceiver.ChunkConstruct.Data
};
responseToken = TokenHelper.TokenNone;
return(true);
}
ChunkReceiver.Start(endPoint, Connections[i], i);
}
}
foundSlot = i;
break;
}
}
if (foundSlot >= 0)
{
continue;
}
var accept = TokenManager.ProcessMessage(endPoint, ChunkReceiver.ChunkConstruct);
if (accept <= 0)
{
continue;
}
if (ChunkReceiver.ChunkConstruct.Flags.HasFlag(PacketFlags.Control))
{
if (ChunkReceiver.ChunkConstruct.Data[0] == (int)ConnectionMessages.Connect)
{
if (sameIps >= Config.MaxClientsPerIp)
{
NetworkHelper.SendConnectionMsg(UdpClient, endPoint,
ChunkReceiver.ChunkConstruct.ResponseToken, 0,
ConnectionMessages.Close, $"Only {Config.MaxClientsPerIp} players with the same IP are allowed");
return(false);
}
if (freeSlot >= 0)
{
Connections[freeSlot].SetToken(ChunkReceiver.ChunkConstruct.Token);
Connections[freeSlot].Feed(ChunkReceiver.ChunkConstruct, endPoint);
OnClientConnected(freeSlot);
continue;
}
NetworkHelper.SendConnectionMsg(UdpClient, endPoint,
ChunkReceiver.ChunkConstruct.ResponseToken, 0,
ConnectionMessages.Close, "This server is full");
return(false);
}
if (ChunkReceiver.ChunkConstruct.Data[0] == (int)ConnectionMessages.Token)
{
TokenCache.AddToken(endPoint, ChunkReceiver.ChunkConstruct.ResponseToken,
TokenFlags.ResponseOnly);
}
}
else if (ChunkReceiver.ChunkConstruct.Flags.HasFlag(PacketFlags.Connless))
{
packet = new Chunk()
{
Flags = SendFlags.Connless,
ClientId = -1,
EndPoint = endPoint,
DataSize = ChunkReceiver.ChunkConstruct.DataSize,
Data = ChunkReceiver.ChunkConstruct.Data,
};
responseToken = ChunkReceiver.ChunkConstruct.ResponseToken;
return(true);
}
}
}
public override bool Send(Chunk packet, uint token = TokenHelper.TokenNone)
{
if (packet.Flags.HasFlag(SendFlags.Connless))
{
if (packet.DataSize >= NetworkHelper.MaxPayload)
{
Debug.Warning("netserver", $"packet payload too big ({packet.DataSize}). dropping packet");
return(false);
}
if (packet.ClientId == -1)
{
for (var i = 0; i < Connections.Count; i++)
{
if (Connections[i].State != ConnectionState.Offline &&
Connections[i].EndPoint != null &&
Connections[i].EndPoint.Compare(packet.EndPoint, comparePorts: true))
{
packet.ClientId = i;
break;
}
}
}
if (token != TokenHelper.TokenNone)
{
NetworkHelper.SendPacketConnless(UdpClient, packet.EndPoint, token,
TokenManager.GenerateToken(packet.EndPoint), packet.Data, packet.DataSize);
}
else
{
if (packet.ClientId == -1)
{
TokenCache.SendPacketConnless(packet.EndPoint, packet.Data, packet.DataSize);
}
else
{
Debug.Assert(packet.ClientId >= 0 &&
packet.ClientId < Connections.Count, "errornous client id");
Connections[packet.ClientId].SendPacketConnless(packet.Data, packet.DataSize);
}
}
}
else
{
if (packet.DataSize + NetworkHelper.MaxChunkHeaderSize >= NetworkHelper.MaxPayload)
{
Debug.Warning("netserver", $"packet payload too big ({packet.DataSize}). dropping packet");
return(false);
}
Debug.Assert(packet.ClientId >= 0 &&
packet.ClientId < Connections.Count, "errornous client id");
var flags = packet.Flags.HasFlag(SendFlags.Vital)
? ChunkFlags.Vital
: ChunkFlags.None;
if (Connections[packet.ClientId].QueueChunk(flags, packet.Data, packet.DataSize))
{
if (packet.Flags.HasFlag(SendFlags.Flush))
{
Connections[packet.ClientId].Flush();
}
}
else
{
Drop(packet.ClientId, "Error sending data");
}
}
return(true);
}