/// <summary>
/// Are about to send a new message
/// </summary>
/// <param name="message">Message to send</param>
/// <remarks>
/// Can be used to prepare the next message. for instance serialize it etc.
/// </remarks>
/// <exception cref="NotSupportedException">Message is of a type that the encoder cannot handle.</exception>
public void Prepare(object message)
{
if (message is IWebSocketMessage)
{
_message = (IWebSocketMessage)message;
_message.Payload.Position = 0;
_totalAmountToSend = (int)_message.Payload.Length;
}
else
{
try
{
_httpMessageEncoder.Prepare(message);
var httpMessage = message as IHttpMessage;
if (WebSocketUtils.IsWebSocketUpgrade(httpMessage))
{
_handshake = httpMessage;
}
}
catch (Exception e)
{
throw new InvalidOperationException("This encoder only supports messages deriving from 'HttpMessage' or 'WebSocketMessage'", e);
}
}
}
public WebSocketFrame(
WebSocketFin fin,
WebSocketRsv rsv1,
WebSocketRsv rsv2,
WebSocketRsv rsv3,
WebSocketOpcode opcode,
WebSocketMask mask,
byte[] maskingKey,
Stream payload
)
: this(fin, rsv1, rsv2, rsv3, opcode, mask, maskingKey, 0, new byte[0], payload)
{
if (payload != null)
{
var len = payload.Length;
if (len < 126)
{
_payloadLength = (byte)len;
_extPayloadLength = new byte[0];
}
else if (len < 0x010000)
{
_payloadLength = (byte)126;
_extPayloadLength = WebSocketUtils.GetBigEndianBytes((ushort)len);
}
else
{
_payloadLength = (byte)127;
_extPayloadLength = WebSocketUtils.GetBigEndianBytes((ulong)len);
}
}
}
/// <summary>
/// Create a new instance of <see cref="WebSocketUpgradeResponse"/>
/// </summary>
/// <param name="webSocketKey">Key from the HTTP request.</param>
public WebSocketUpgradeResponse(string webSocketKey)
: base(HttpStatusCode.SwitchingProtocols, "Switching Protocols", "HTTP/1.1")
{
Headers["Upgrade"] = "websocket";
Headers["Connection"] = "Upgrade";
Headers["Sec-WebSocket-Accept"] = WebSocketUtils.HashWebSocketKey(webSocketKey);
}
/// <summary>
/// Intercept http messages and look for websocket upgrade requests
/// </summary>
/// <param name="message">message from http decoder</param>
private void OnHttpMessage(object message)
{
var httpMessage = message as IHttpMessage;
// TODO: is there a better way to detect WebSocket upgrade?
if (WebSocketUtils.IsWebSocketUpgrade(httpMessage))
{
_handshake = httpMessage;
_isWebSocket = true;
}
_messageReceived(message);
}
public WebSocketFrame(
WebSocketFin fin,
WebSocketOpcode opcode,
WebSocketMask mask,
Stream payload
)
: this(fin, WebSocketRsv.Off, WebSocketRsv.Off, WebSocketRsv.Off, opcode, mask, mask == WebSocketMask.Mask ? WebSocketUtils.CreateMaskingKey() : new byte[0], payload)
{
}
/// <summary>
/// Buffer structure used for socket send operations.
/// </summary>
/// <param name="buffer">
/// Do note that there are not buffer attached to the structure, you have to assign one yourself using
/// <see cref="ISocketBuffer.SetBuffer(int,int)" />. This choice was made
/// to prevent unnecessary copy operations.
/// </param>
public void Send(ISocketBuffer buffer)
{
if (_message == null)
{
_httpMessageEncoder.Send(buffer);
}
else
{
// last send operation did not send all bytes enqueued in the buffer
// so let's just continue until doing next message
if (_bytesToSend > 0)
{
buffer.SetBuffer(_buffer, _offset, _bytesToSend);
return;
}
var offset = (int)_message.Payload.Position;
var length = (int)_message.Payload.Length;
var frameLength = length - offset;
var fin = WebSocketFin.Final;
if (frameLength > WebSocketFrame.FragmentLength)
{
frameLength = WebSocketFrame.FragmentLength;
fin = WebSocketFin.More;
}
var opcode = WebSocketOpcode.Continuation;
if (offset == 0) // first frame
{
opcode = _message.Opcode;
}
var buff = new byte[frameLength];
_message.Payload.Read(buff, 0, buff.Length);
var payload = new MemoryStream(buff);
WebSocketFrame frame = new WebSocketFrame(fin, opcode, (_handshake is IHttpRequest) ? WebSocketMask.Mask : WebSocketMask.Unmask, payload);
using (var stream = new MemoryStream())
{
var header = (int)frame.Fin;
header = (header << 1) + (int)frame.Rsv1;
header = (header << 1) + (int)frame.Rsv2;
header = (header << 1) + (int)frame.Rsv3;
header = (header << 4) + (int)frame.Opcode;
header = (header << 1) + (int)frame.Mask;
header = (header << 7) + (int)frame.PayloadLength;
stream.Write(WebSocketUtils.GetBigEndianBytes((ushort)header), 0, 2);
if (frame.PayloadLength > 125)
{
stream.Write(frame.ExtPayloadLength, 0, frame.ExtPayloadLength.Length);
}
if (frame.Mask == WebSocketMask.Mask)
{
stream.Write(frame.MaskingKey, 0, frame.MaskingKey.Length);
frame.Unmask();
}
_totalAmountToSend += (int)stream.Length;
if (frame.PayloadLength > 0)
{
frame.Payload.CopyTo(stream);
}
buffer.UserToken = _message;
_buffer = stream.ToArray();
_bytesToSend = _buffer.Length;
buffer.SetBuffer(_buffer, 0, _bytesToSend);
}
}
}
/// <summary>
/// We've received bytes from the socket. Build a message out of them.
/// </summary>
/// <param name="buffer">Buffer</param>
public void ProcessReadBytes(ISocketBuffer buffer)
{
if (!_isWebSocket)
{
_httpMessageDecoder.ProcessReadBytes(buffer);
}
else
{
var receiveBufferOffset = buffer.Offset;
var bytesLeftInReceiveBuffer = buffer.BytesTransferred;
while (true)
{
if (bytesLeftInReceiveBuffer <= 0)
{
break;
}
if (_frame == null)
{
var first = buffer.Buffer[receiveBufferOffset + 0];
var second = buffer.Buffer[receiveBufferOffset + 1];
var fin = (first & 0x80) == 0x80 ? WebSocketFin.Final : WebSocketFin.More;
var rsv1 = (first & 0x40) == 0x40 ? WebSocketRsv.On : WebSocketRsv.Off;
var rsv2 = (first & 0x20) == 0x20 ? WebSocketRsv.On : WebSocketRsv.Off;
var rsv3 = (first & 0x10) == 0x10 ? WebSocketRsv.On : WebSocketRsv.Off;
var opcode = (WebSocketOpcode)(first & 0x0f);
var mask = (second & 0x80) == 0x80 ? WebSocketMask.Mask : WebSocketMask.Unmask;
var payloadLen = (byte)(second & 0x7f);
receiveBufferOffset += 2;
bytesLeftInReceiveBuffer -= 2;
// TODO:
// check if valid headers
// control frame && payloadLen > 125
// control frame && more
// not data && compressed
var size = payloadLen < 126
? 0
: payloadLen == 126
? 2
: 8;
var extPayloadLen = new byte[size];
for (var i = 0; i < size; i++)
{
extPayloadLen[i] = buffer.Buffer[receiveBufferOffset + i];
}
receiveBufferOffset += size;
bytesLeftInReceiveBuffer -= size;
var maskingKey = new byte[0];
if (mask == WebSocketMask.Mask)
{
maskingKey = new byte[] {
buffer.Buffer[receiveBufferOffset + 0],
buffer.Buffer[receiveBufferOffset + 1],
buffer.Buffer[receiveBufferOffset + 2],
buffer.Buffer[receiveBufferOffset + 3],
};
receiveBufferOffset += 4;
bytesLeftInReceiveBuffer -= 4;
}
ulong len = payloadLen < 126
? payloadLen
: payloadLen == 126
? WebSocketUtils.ToBigEndianUInt16(extPayloadLen)
: WebSocketUtils.ToBigEndianUInt64(extPayloadLen);
_frameContentBytesLeft = (int)len;
_frame = new WebSocketFrame(fin, rsv1, rsv2, rsv3, opcode, mask, maskingKey, payloadLen, extPayloadLen, new MemoryStream(_frameContentBytesLeft));
if (_frame.Fin == WebSocketFin.More || _frame.Opcode == WebSocketOpcode.Continuation)
{
_frames.Add(_frame);
}
}
if (_frameContentBytesLeft > 0)
{
var bytesRead = BytesProcessed(buffer.Offset, receiveBufferOffset);
var bytesToWrite = Math.Min(_frameContentBytesLeft, buffer.BytesTransferred - bytesRead);
_frame.Payload.Write(buffer.Buffer, receiveBufferOffset, bytesToWrite);
_frameContentBytesLeft -= bytesToWrite;
receiveBufferOffset += bytesToWrite;
bytesLeftInReceiveBuffer -= bytesToWrite;
}
if (_frameContentBytesLeft == 0)
{
_frame.Payload.Position = 0;
if (_frame.Fin == WebSocketFin.Final)
{
if (_frame.Opcode == WebSocketOpcode.Continuation)
{
TriggerMessageReceived(_frames);
_frames = new List <WebSocketFrame>();
}
else
{
TriggerMessageReceived(new[] { _frame });
}
}
_frame = null;
}
}
}
}
/// <summary>
/// Handles the upgrade
/// </summary>
/// <param name="source">Channel that we've received a request from</param>
/// <param name="msg">Message received.</param>
protected override void OnMessage(ITcpChannel source, object msg)
{
var httpMessage = msg as IHttpMessage;
if (WebSocketUtils.IsWebSocketUpgrade(httpMessage))
{
if (httpMessage is IHttpRequest) // server mode
{
var args = new WebSocketClientConnectEventArgs(source, (IHttpRequest)httpMessage);
WebSocketClientConnect(this, args);
if (args.MayConnect)
{
var webSocketKey = httpMessage.Headers["Sec-WebSocket-Key"];
// TODO: why not provide the response in the WebSocketClientConnectEventArgs event?
var response = new WebSocketUpgradeResponse(webSocketKey);
source.Send(response);
WebSocketClientConnected(this,
new WebSocketClientConnectedEventArgs(source, (IHttpRequest)httpMessage, response));
}
else
{
var response = new HttpResponseBase(HttpStatusCode.NotImplemented, "Not Implemented", "HTTP/1.1");
if (args.Response != null)
{
response.Body = args.Response;
}
source.Send(response);
}
return;
}
if (httpMessage is IHttpResponse) // client mode
{
WebSocketClientConnected(this,
new WebSocketClientConnectedEventArgs(source, null, (IHttpResponse)httpMessage));
}
}
var webSocketMessage = msg as IWebSocketMessage;
if (webSocketMessage != null)
{
// standard message responses handled by listener
switch (webSocketMessage.Opcode)
{
case WebSocketOpcode.Ping:
source.Send(new WebSocketMessage(WebSocketOpcode.Pong, webSocketMessage.Payload));
return;
case WebSocketOpcode.Close:
source.Send(new WebSocketMessage(WebSocketOpcode.Close));
source.Close();
WebSocketClientDisconnected(this,
new ClientDisconnectedEventArgs(source, new Exception("WebSocket closed")));
return;
}
_webSocketMessageReceived(source, webSocketMessage);
return;
}
base.OnMessage(source, msg);
}
