private void ProcessReceive(SocketAsyncEventArgs args)
{
_idleTimeoutTimer?.Stop();
_readTimeoutTimer?.Stop();
if (args.BytesTransferred > 0 && args.SocketError == SocketError.Success)
{
ReceiveToken token = (ReceiveToken)args.UserToken;
token.BufferLength += args.BytesTransferred;
if (Socket.Available == 0)
{
byte[] receiveBuffer = new byte[token.BufferLength];
Array.Copy(args.Buffer, receiveBuffer, token.BufferLength);
token.BufferLength = 0;
token.ReceiveHandler(receiveBuffer);
StartReceive(args);
}
else if (Socket.ReceiveAsync(args) == false)
{
// Read the next block of data sent by client.
ProcessReceive(args);
}
}
else
{
if (Socket.Connected)
{
Close();
}
}
}
private static readonly byte[] HEADER_DELIM = { 13, 10, 13, 10 }; // UTF-8 for \r\n\r\n i.e. CRLF CRLF, which appears after the last HTTP header field
protected byte[] HandleHttpHeader(SocketAsyncEventArgs e, ref int bytesAlreadyProcessed)
{
if (bytesAlreadyProcessed < 0)
{
throw new ArgumentException("bytesAlreadyProcessed must be non-negative.");
}
else if (bytesAlreadyProcessed >= e.BytesTransferred)
{
throw new ArgumentException("bytesAlreadyProcessed must be less than e.BytesTransferred.");
}
ReceiveToken token = (ReceiveToken)e.UserToken;
int totalBytes = token.bytesReceived + e.BytesTransferred - bytesAlreadyProcessed;
if (totalBytes >= 4)
{
int searchSpace = totalBytes - 3; // totalBytes - HEADER_DELIM.Length + 1
byte[] data = token.internalBuffer.Array;
for (int i = 0; i < searchSpace; i++)
{
if (HEADER_DELIM[0] == data[token.internalBuffer.Offset + i])
{
if (HEADER_DELIM[1] == data[token.internalBuffer.Offset + i + 1] &&
HEADER_DELIM[2] == data[token.internalBuffer.Offset + i + 2] &&
HEADER_DELIM[3] == data[token.internalBuffer.Offset + i + 3])
{
byte[] header = new byte[i + 4];
Buffer.BlockCopy(data, token.internalBuffer.Offset, header, 0, header.Length);
if (token.bytesReceived > 0)
{
bytesAlreadyProcessed += header.Length - token.bytesReceived;
token.bytesReceived = 0;
e.SetBuffer(token.internalBuffer.Offset, token.internalBuffer.Count);
}
else
{
bytesAlreadyProcessed += header.Length;
}
if (header.Length < totalBytes)
{
Buffer.BlockCopy(data, token.internalBuffer.Offset + header.Length, data, token.internalBuffer.Offset, totalBytes - header.Length);
}
e.UserToken = token;
return(header);
}
}
}
if (totalBytes == token.internalBuffer.Count)
{
throw new Exception(String.Format("Could not find end of header within {0} bytes.", token.internalBuffer.Count));
}
}
token.bytesReceived = totalBytes;
e.SetBuffer(token.internalBuffer.Offset + totalBytes, token.internalBuffer.Count - totalBytes);
bytesAlreadyProcessed = e.BytesTransferred;
e.UserToken = token;
return(null);
}
private void ReturnBuffer(SocketAsyncEventArgs e)
{
if (e.UserToken != null)
{
ReceiveToken token = (ReceiveToken)e.UserToken;
bufferManager.ReturnBuffer(token.internalBuffer);
token.internalBuffer = default(ArraySegment <byte>);
e.SetBuffer(new byte[0], 0, 0);
}
}
public void Receive(Action <byte[]> buffer)
{
ReceiveToken token = new ReceiveToken
{
ReceiveHandler = buffer
};
ReceiveSocketAsyncEventArgs.UserToken = token;
StartReceive(ReceiveSocketAsyncEventArgs);
}
// Should validate the handshake response from the server
private void ReceiveAsync_Completed(object sender, SocketAsyncEventArgs e)
{
if (e.BytesTransferred > 0 && e.SocketError == SocketError.Success)
{
int bytesAlreadyProcessed = 0; // Count of the total freshly transferred bytes processed so far
ReceiveToken token = (ReceiveToken)e.UserToken;
if (!headerExchanged)
{
byte[] header = HandleHttpHeader(e, ref bytesAlreadyProcessed);
token = (ReceiveToken)e.UserToken;
if (header == null)
{
DoRead(e);
return;
}
else if (Websockets.ValidateResponseHeader(headerHash, header))
{
headerExchanged = true;
token.maxAllowedBytes = int.MaxValue;
e.UserToken = token;
// Ping the server to finalize the player's connection
Send(Text.CreateFromString(Time.Timestep, InstanceGuid.ToString(), true, Receivers.Server,
MessageGroupIds.NETWORK_ID_REQUEST, true));
}
else
{
// Improper header, so a disconnect is required
Disconnect(true);
return;
}
}
while (bytesAlreadyProcessed < e.BytesTransferred)
{
byte[] data = HandleData(e, true, ref bytesAlreadyProcessed);
if (data == null)
{
break;
}
FrameStream frame = Factory.DecodeMessage(data, false, MessageGroupIds.TCP_FIND_GROUP_ID, Server);
FireRead(frame, Server);
}
DoRead(e);
}
else
{
Disconnect(true);
}
}
protected virtual void Initialize(string host, ushort port, bool pendCreates = true)
{
// By default pending creates should be true and flushed when ready
if (pendCreates)
{
PendCreates = true;
}
// Get a random hash key that needs to be used for validating that the server was connected to
headerHash = Websockets.HeaderHashKey();
// This is a typical Websockets accept header to be validated
byte[] connectionHeader = Websockets.ConnectionHeader(headerHash, port);
// Register the server as a NetworkingPlayer
server = new NetworkingPlayer(0, host, true, client, this);
// Send the upgrade request to the server
RawWrite(connectionHeader);
//Let myself know I connected successfully
OnPlayerConnected(server);
// Set myself as a connected client
server.Connected = true;
ReceiveToken token = new ReceiveToken
{
internalBuffer = new ArraySegment <byte>(buffer, 0, buffer.Length),
player = server,
bytesReceived = 0,
dataHolder = null,
maxAllowedBytes = 8192
};
// Read from the server async
SocketAsyncEventArgs e = new SocketAsyncEventArgs();
e.Completed += new EventHandler <SocketAsyncEventArgs>(ReceiveAsync_Completed);
e.UserToken = token;
e.SetBuffer(token.internalBuffer.Array, token.internalBuffer.Offset, token.internalBuffer.Count);
if (!client.Client.ReceiveAsync(e))
{
Task.Queue(() => ReceiveAsync_Completed(this, e));
}
}
private void DoRead(SocketAsyncEventArgs e)
{
if (!IsBound)
{
ReturnBuffer(e);
return;
}
ReceiveToken token = (ReceiveToken)e.UserToken;
Socket playerSocket = null;
try
{
// Try to get the client stream if it is still available
playerSocket = token.player.TcpClientHandle.Client;
}
catch
{
// Failed to get the stream for the client so forcefully disconnect it
//Console.WriteLine("Exception: Failed to get stream for client (Forcefully disconnecting)");
Disconnect(token.player, true);
ReturnBuffer(e);
return;
}
// If the player is no longer connected, then make sure to disconnect it properly
if (!token.player.TcpClientHandle.Connected)
{
Disconnect(token.player, false);
ReturnBuffer(e);
return;
}
// False means operation was synchronous (usually error)
if (!playerSocket.ReceiveAsync(e))
{
ReceiveAsync_Completed(this, e);
}
}
protected byte[] HandleData(SocketAsyncEventArgs e, bool isStream, ref int bytesAlreadyProcessed)
{
if (bytesAlreadyProcessed < 0)
{
throw new ArgumentException("bytesAlreadyProcessed must be non-negative.");
}
else if (bytesAlreadyProcessed >= e.BytesTransferred)
{
throw new ArgumentException("bytesAlreadyProcessed must be less than e.BytesTransferred.");
}
ReceiveToken token = (ReceiveToken)e.UserToken;
int socketOffset = token.internalBuffer.Offset;
byte[] bytes = token.internalBuffer.Array;
int totalBytes;
#region ParseFrameHeader
if (token.dataHolder == null) // Null dataHolder means header not parsed yet
{
totalBytes = token.bytesReceived + e.BytesTransferred - bytesAlreadyProcessed;
if (totalBytes < 2) // Not enough bytes to determine length, so move offset
{
token.bytesReceived = totalBytes;
e.SetBuffer(socketOffset + totalBytes, token.internalBuffer.Count - totalBytes);
bytesAlreadyProcessed = e.BytesTransferred;
e.UserToken = token;
return(null);
}
int dataLength = bytes[socketOffset + 1] & 127;
bool usingMask = bytes[socketOffset + 1] > 127; // same as bytes[socketOffset + 1] & 128 != 0
int payloadOffset;
if (dataLength == 126) // 126 means 125 < length < 65536
{
payloadOffset = 4;
}
else if (dataLength == 127) // 127 means length >= 65536
{
payloadOffset = 10;
}
else
{
payloadOffset = 2;
}
int length;
if (payloadOffset != 2)
{
if (totalBytes < payloadOffset) // Not enough bytes to determine length, so move offset
{
token.bytesReceived = totalBytes;
e.SetBuffer(socketOffset + totalBytes, token.internalBuffer.Count - totalBytes);
bytesAlreadyProcessed = e.BytesTransferred;
e.UserToken = token;
return(null);
}
// Need to worry about endian order since length is in big endian
if (payloadOffset == 4)
{
if (BitConverter.IsLittleEndian)
{
length = BitConverter.ToUInt16(new byte[] { bytes[socketOffset + 3], bytes[socketOffset + 2] }, 0);
}
else
{
length = BitConverter.ToUInt16(bytes, socketOffset + 2);
}
}
else
{
// First 4 bytes will be 0 for sizes less than max int32
if (BitConverter.IsLittleEndian)
{
length = (int)BitConverter.ToUInt32(new byte[] { bytes[socketOffset + 9], bytes[socketOffset + 8], bytes[socketOffset + 7], bytes[socketOffset + 6] }, 0);
}
else
{
length = (int)BitConverter.ToUInt32(bytes, socketOffset + 6);
}
}
// Group id, receivers, time step, unique id, and router id lengths will be present in the payload length
//if (isStream)
// length += 21; // Group id (4), receivers (1), time step (8), unique id (8)
//if ((bytes[socketOffset + 0] & 0xF) == (Binary.CONTROL_BYTE & 0xF))
// length += 1; // routerId (1) if this is a binary frame
}
else
{
length = dataLength;
}
length += usingMask ? 4 + payloadOffset : payloadOffset; // Add full length of header to length
if (length < 0 || length > token.maxAllowedBytes)
{
throw new UnauthorizedAccessException(String.Format("Tried to receive a frame larger than expected. Got {0}, and expected less than {1}", length, token.maxAllowedBytes));
}
e.SetBuffer(token.internalBuffer.Offset, token.internalBuffer.Count);
token.bytesReceived = 0;
token.dataHolder = new byte[length];
}
#endregion
totalBytes = token.bytesReceived + e.BytesTransferred - bytesAlreadyProcessed;
if (totalBytes < token.dataHolder.Length) // Full frame not yet received
{
Buffer.BlockCopy(bytes, socketOffset, token.dataHolder, token.bytesReceived, e.BytesTransferred - bytesAlreadyProcessed);
token.bytesReceived += e.BytesTransferred - bytesAlreadyProcessed;
bytesAlreadyProcessed = e.BytesTransferred;
e.UserToken = token;
return(null);
}
else
{
byte[] data = token.dataHolder;
int dataProcessed = (data.Length - token.bytesReceived);
Buffer.BlockCopy(bytes, socketOffset, data, token.bytesReceived, dataProcessed);
token.bytesReceived = 0;
token.dataHolder = null;
bytesAlreadyProcessed += dataProcessed;
if (bytesAlreadyProcessed < e.BytesTransferred) // More frames left to handle, so shuffle the remaining data to beginning of buffer.
{
Buffer.BlockCopy(bytes, socketOffset + dataProcessed, bytes, socketOffset, e.BytesTransferred - bytesAlreadyProcessed);
}
e.UserToken = token;
return(data);
}
}
public TokenInput(ReceiveToken callback)
{
this.callback = callback;
}
private void ReceiveAsync_Completed(object sender, SocketAsyncEventArgs e)
{
if (e.BytesTransferred > 0 && e.SocketError == SocketError.Success)
{
int bytesAlreadyProcessed = 0;
ReceiveToken token = (ReceiveToken)e.UserToken;
if (!token.player.Accepted && !token.player.Connected)
{
byte[] header = HandleHttpHeader(e, ref bytesAlreadyProcessed);
if (header == null)
{
DoRead(e);
return;
}
byte[] response = Websockets.ValidateConnectionHeader(header);
// The response will be null if the header sent is invalid, if so then disconnect client as they are sending invalid headers
if (response == null)
{
OnPlayerRejected(token.player);
Disconnect(token.player, true);
ReturnBuffer(e);
return;
}
// If all is in order then send the validated response to the client
token.player.TcpClientHandle.GetStream().Write(response, 0, response.Length);
// The player has successfully connected
token.player.Connected = true;
}
while (bytesAlreadyProcessed < e.BytesTransferred)
{
byte[] data = HandleData(e, true, ref bytesAlreadyProcessed);
if (data == null)
{
break;
}
FrameStream frame = Factory.DecodeMessage(data, true, MessageGroupIds.TCP_FIND_GROUP_ID, token.player);
if (!token.player.Accepted)
{
if (frame.GroupId == MessageGroupIds.NETWORK_ID_REQUEST)
{
token.player.InstanceGuid = ((Text)frame).ToString();
// If the player was rejected during the handling of the playerGuidAssigned event, don't accept them.
if (!TryPlayerGuidAssignment(token.player))
{
break;
}
token.maxAllowedBytes = int.MaxValue;
if (authenticator != null)
{
authenticator.IssueChallenge(this, token.player, IssueChallenge, AuthUser);
}
else
{
AuthUser(token.player);
}
}
else if (frame.GroupId == MessageGroupIds.AUTHENTICATION_RESPONSE)
{
// Authenticate user response
if (authenticator == null)
{
return;
}
authenticator.VerifyResponse(this, token.player, frame.StreamData, AuthUser, RejectUser);
}
else
{
Disconnect(token.player, true);
ReturnBuffer(e);
}
}
else
{
token.player.Ping();
FireRead(frame, token.player);
}
}
DoRead(e);
}
else
{
Disconnect(((ReceiveToken)e.UserToken).player, true);
ReturnBuffer(e);
}
}
/// <summary>
/// Infinite loop listening for client connections on a separate thread.
/// This loop breaks if there is an exception thrown on the blocking accept call
/// </summary>
private void ListenForConnections(IAsyncResult obj)
{
TcpListener asyncListener = (TcpListener)obj.AsyncState;
TcpClient client = null;
try
{
client = asyncListener.EndAcceptTcpClient(obj);
}
catch
{
return;
}
asyncListener.BeginAcceptTcpClient(ListenForConnections, asyncListener);
if (rawClients.Count == MaxConnections)
{
// Tell the client why they are being disconnected
Send(client, Error.CreateErrorMessage(Time.Timestep, "Max Players Reached On Server", false, MessageGroupIds.MAX_CONNECTIONS, true));
// Send the close connection frame to the client
Send(client, new ConnectionClose(Time.Timestep, false, Receivers.Target, MessageGroupIds.DISCONNECT, true));
// Do disconnect logic for client
ClientRejected(client, false);
return;
}
else if (!AcceptingConnections)
{
// Tell the client why they are being disconnected
Send(client, Error.CreateErrorMessage(Time.Timestep, "The server is busy and not accepting connections", false, MessageGroupIds.MAX_CONNECTIONS, true));
// Send the close connection frame to the client
Send(client, new ConnectionClose(Time.Timestep, false, Receivers.Target, MessageGroupIds.DISCONNECT, true));
// Do disconnect logic for client
ClientRejected(client, false);
return;
}
ArraySegment <byte> segment;
if (!bufferManager.TryTakeBuffer(out segment))
{
// Tell the client why they are being disconnected
Send(client, Error.CreateErrorMessage(Time.Timestep, "The server is busy and not accepting connections", false, MessageGroupIds.MAX_CONNECTIONS, true));
// Send the close connection frame to the client
Send(client, new ConnectionClose(Time.Timestep, false, Receivers.Target, MessageGroupIds.DISCONNECT, true));
// Do disconnect logic for client
ClientRejected(client, false);
throw new OutOfMemoryException("Buffer manager has run out of allocated memory (possible memory leak).");
}
// Clients will be looped through on other threads so be sure to lock it before adding
ReceiveToken token;
lock (Players)
{
rawClients.Add(client);
// Create the identity wrapper for this player
NetworkingPlayer player = new NetworkingPlayer(ServerPlayerCounter++, ((IPEndPoint)client.Client.RemoteEndPoint).Address.ToString(), false, client, this);
// Generically add the player and fire off the events attached to player joining
OnPlayerConnected(player);
token = new ReceiveToken
{
internalBuffer = segment,
player = player,
bytesReceived = 0,
dataHolder = null,
maxAllowedBytes = 8192
};
}
// Let all of the event listeners know that the client has successfully connected
if (rawClientConnected != null)
{
rawClientConnected(client);
}
SocketAsyncEventArgs e = new SocketAsyncEventArgs();
e.Completed += new EventHandler <SocketAsyncEventArgs>(ReceiveAsync_Completed);
e.UserToken = token;
e.SetBuffer(token.internalBuffer.Array, token.internalBuffer.Offset, token.internalBuffer.Count);
if (!client.Client.ReceiveAsync(e))
{
Task.Queue(() => ReceiveAsync_Completed(this, e));
}
}