protected void DoSendPongMessage()
{
WSFrame wsFrame = WSFrame.CreateFrame(WSFrameType.Pong, this.options.MaskingEnabled, "Hello");
this.LogBufferContent("Sending pong frame: ", wsFrame.FrameData, 0, wsFrame.FrameData.Length);
this.socketStream.Write(wsFrame.FrameData, 0, wsFrame.FrameData.Length);
}
protected void DoSendCloseFrame()
{
WSFrame wsFrame = WSFrame.CreateFrame(WSFrameType.Close, this.options.MaskingEnabled, ArrayUtil.Concat(this.closeStatus, this.closeReason));
this.LogBufferContent("Sending close frame: ", wsFrame.FrameData, 0, wsFrame.FrameData.Length);
this.socketStream.Write(wsFrame.FrameData, 0, wsFrame.FrameData.Length);
this.subState = SubState.WaitForCloseResponse;
}
/// <summary>
/// Removes the WSFrame at the top of the queue, and returns it.
/// </summary>
/// <returns>The WSFrame that is removed from the top of the queue.</returns>
public WSFrame Dequeue()
{
WSFrame wsFrame = null;
lock (this.queue.SyncRoot)
{
wsFrame = (WSFrame)this.queue.Dequeue();
}
return(wsFrame);
}
/// <summary>
/// Adds a WSFrame to the bottom of the queue.
/// </summary>
/// <param name="wsFrame">The WSFrame to add to the queue.</param>
/// <remarks>If Count == MaxCount, then the WSFrame at the top of the queue is removed and discarded before the new entry is added.</remarks>
public void Enqueue(WSFrame wsFrame)
{
lock (this.queue.SyncRoot)
{
if (this.queue.Count == this.maxCount)
{
this.queue.Dequeue();
}
this.queue.Enqueue(wsFrame);
}
}
public static void ApplyMask(WSFrame wsFrame)
{
if (wsFrame != null && wsFrame.payloadLength > 0)
{
int maskIndex = 0;
for (int i = 0; i < wsFrame.payloadLength; i++)
{
maskIndex = wsFrame.maskIndex + (i % 4);
wsFrame.frameData[wsFrame.payloadIndex + i] = (byte)(wsFrame.frameData[wsFrame.payloadIndex + i] ^ wsFrame.frameData[maskIndex]);
}
}
}
protected void EnqueueMessage(WSFrameType opCode, bool isMasked, byte[] payLoad, bool highPriority = false)
{
WSFrame wsFrame = WSFrame.CreateFrame(opCode, isMasked, payLoad);
if (highPriority)
{
this.sendQueue.Poke(wsFrame);
}
else
{
this.sendQueue.Enqueue(wsFrame);
}
}
protected bool DequeueAndSendMessages()
{
bool messagesSent = this.sendQueue.Count > 0;
lock (this.sendLock)
{
while (this.sendQueue.Count > 0)
{
WSFrame wsFrame = this.sendQueue.Dequeue();
this.LogBufferContent("Sending data frame: ", wsFrame.FrameData, 0, wsFrame.FrameData.Length);
this.socketStream.Write(wsFrame.FrameData, 0, wsFrame.FrameData.Length);
}
}
return(messagesSent);
}
/// <summary>
/// Inserts a WSFrame at the top of the queue.
/// </summary>
/// <param name="wsFrame">The WSFrame to add to the queue.</param>
/// <remarks>May be used to insert high-priority messages at the top of the queue.</remarks>
public void Poke(WSFrame wsFrame)
{
lock (this.queue.SyncRoot)
{
if (this.queue.Count > this.maxCount)
{
this.queue.Dequeue();
}
int count = this.queue.Count;
this.queue.Enqueue(wsFrame);
while (count > 0)
{
this.queue.Enqueue(this.queue.Dequeue());
}
}
}
protected void DoSendCloseResponse()
{
byte[] payLoad = null;
if (this.lastRcvdFrame.OpCode == WSFrameType.Close && this.lastRcvdFrame.PayloadLength > 0)
{
// reply with the same status code and reason
payLoad = this.lastRcvdFrame.PayloadBytes;
}
WSFrame wsFrame = WSFrame.CreateFrame(WSFrameType.Close, this.options.MaskingEnabled, payLoad);
this.LogBufferContent("Sending close frame: ", wsFrame.FrameData, 0, wsFrame.FrameData.Length);
this.socketStream.Write(wsFrame.FrameData, 0, wsFrame.FrameData.Length);
this.socketStream.Flush();
this.subState = SubState.CloseTcpConnection;
}
protected void DoWaitCloseResponse()
{
int bytesRead = 0;
this.posHeaderEOF = 0;
this.bytesInBuffer = 0;
if (this.socket.Poll(this.waitCloseMsgTimeout, SelectMode.SelectRead) == true && this.socket.Available > 0)
{
do
{
bytesRead = this.socketStream.Read(this.receiveBuffer, this.bytesInBuffer, this.receiveBuffer.Length - this.bytesInBuffer);
if (bytesRead > 0)
{
this.bytesInBuffer += bytesRead;
if (WSFrame.TryParse(this.receiveBuffer, 0, this.bytesInBuffer, this.options.MaxReceiveFrameLength, out this.lastRcvdFrame) == true)
{
// remove data-frame from buffer
Array.Copy(this.receiveBuffer, this.lastRcvdFrame.FrameData.Length, this.receiveBuffer, 0, this.bytesInBuffer - this.lastRcvdFrame.FrameData.Length);
this.bytesInBuffer = this.bytesInBuffer - this.lastRcvdFrame.FrameData.Length;
// check for close frame
if (this.lastRcvdFrame.OpCode == WSFrameType.Close)
{
this.LogBufferContent("Close frame received: ", this.lastRcvdFrame.FrameData, 0, this.lastRcvdFrame.FrameData.Length);
this.subState = SubState.CloseTcpConnection;
return;
}
this.LogBufferContent("Data frame received: ", this.lastRcvdFrame.FrameData, 0, this.lastRcvdFrame.FrameData.Length);
}
}
}while (this.socket.Available > 0 && this.bytesInBuffer < this.receiveBuffer.Length);
}
Logger.WriteError(this.loggerID, "Close frame not received.");
this.subState = SubState.Failed;
}
/// <summary>
/// Parses a byte-array at startPos to its equivalent RFC 6455 BFP frame. The return value indicates whether the operation succeeded.
/// </summary>
/// <param name="dataBuffer">A source byte-array containing the bytes to convert.</param>
/// <param name="startPos">Start position in the source byte-array.</param>
/// <param name="length">Number of bytes to parse.</param>
/// <param name="maxFrameLength">Maximum frame size allowed.</param>
/// <param name="dataFrame">The resulting BFP frame or null.</param>
/// <returns>true if the source byte-array was converted successfully; otherwise, false</returns>
public static bool TryParse(byte[] dataBuffer, int startPos, int length, int maxFrameLength, out WSFrame dataFrame)
{
dataFrame = null;
if (dataBuffer == null || dataBuffer.Length == 0 || dataBuffer.Length < (startPos + length))
{
return(false);
}
byte controlByte0 = dataBuffer[startPos];
byte controlByte1 = dataBuffer[startPos + 1];
byte length8 = (byte)(controlByte1 & 0x7F);
bool isMasked = ((controlByte1 & 0x80) == 0x80);
int maskIndex = 0;
byte[] mask = new byte[4];
// get payload index and length
Int32 payloadIndex = 0;
UInt64 payloadLength64 = 0;
if (length8 == 127)
{
maskIndex = (isMasked ? 10 : 0);
payloadIndex = (isMasked ? 14 : 10);
payloadLength64 = dataBuffer.ToUInt64(startPos + 2);
}
else if (length8 == 126)
{
maskIndex = (isMasked ? 4 : 0);
payloadIndex = (isMasked ? 8 : 4);
payloadLength64 = dataBuffer.ToUInt16(startPos + 2);
}
else // must be <= 125
{
maskIndex = (isMasked ? 2 : 0);
payloadIndex = (isMasked ? 6 : 2);
payloadLength64 = length8;
}
// calculate frame length
Int32 frameLength = payloadIndex + (Int32)payloadLength64;
// check for max allowed length
if (frameLength > maxFrameLength)
{
throw new NotSupportedException(string.Concat("Maximum frame size of ", maxFrameLength, " bytes has been exceeded."));
}
// create WSFrame if full frame has been received
if (frameLength <= length)
{
dataFrame = new WSFrame()
{
maskIndex = maskIndex,
payloadIndex = payloadIndex,
payloadLength = (Int32)payloadLength64,
frameData = new byte[frameLength]
};
Array.Copy(dataBuffer, startPos, dataFrame.frameData, 0, frameLength);
if (isMasked)
{
ApplyMask(dataFrame);
}
return(true);
}
return(false);
}
/// <summary>
/// Creates an RFC 6455 BFP frame with the opcode and payload bytes specified.
/// </summary>
/// <param name="opCode">BFP opcode.</param>
/// <param name="isMasked">Boolean indicating whether to mask the payload.</param>
/// <param name="payLoad">Payload bytes.</param>
/// <returns></returns>
public static WSFrame CreateFrame(WSFrameType opCode, bool isMasked, byte[] payLoad)
{
// TODO - add code to support continuation frames
// - add long maxFrameLength parameter
// - return array of WSFrame objects
byte controlByte0 = (byte)(0x80 | (byte)opCode);
byte controlByte1 = (isMasked && payLoad != null && payLoad.Length > 0 ? (byte)0x80 : (byte)0x00);
byte[] mask = (isMasked ? CryptoUtils.GetRandomBytes(4) : new byte[0]);
int maskIndex = 0;
Int32 payloadIndex = 0;
UInt16 length16 = 0;
UInt32 length32 = 0;
UInt64 length64 = 0;
byte[] frameData = null;
if (payLoad == null || payLoad.Length == 0)
{
length32 = 0;
payloadIndex = 0;
frameData = ArrayUtil.Concat(controlByte0, controlByte1);
}
else if (payLoad.Length <= 125)
{
controlByte1 = (byte)(controlByte1 | (byte)payLoad.Length);
length32 = (UInt32)payLoad.Length;
maskIndex = (isMasked ? 2 : 0);
payloadIndex = (isMasked ? 6 : 2);
frameData = ArrayUtil.Concat(controlByte0, controlByte1, mask, payLoad);
}
else if (payLoad.Length <= UInt16.MaxValue)
{
controlByte1 = (byte)(controlByte1 | (byte)126);
length16 = (UInt16)payLoad.Length;
length32 = length16;
maskIndex = (isMasked ? 4 : 0);
payloadIndex = (isMasked ? 8 : 4);
frameData = ArrayUtil.Concat(controlByte0, controlByte1, length16, mask, payLoad);
}
else
{
controlByte1 = (byte)(controlByte1 | (byte)127);
length32 = (UInt32)payLoad.Length;
length64 = (UInt64)payLoad.Length;
maskIndex = (isMasked ? 10 : 0);
payloadIndex = (isMasked ? 14 : 10);
frameData = ArrayUtil.Concat(controlByte0, controlByte1, length64, mask, payLoad);
}
WSFrame dataFrame = new WSFrame()
{
maskIndex = maskIndex,
payloadIndex = payloadIndex,
payloadLength = (Int32)length32,
frameData = frameData
};
if (isMasked)
{
// Logger.WriteDebug("wsframe", string.Concat("raw: ", frameData.ToHex()));
ApplyMask(dataFrame);
}
return(dataFrame);
}
protected void DoReceiving()
{
// process data in buffer
if (this.bytesInBuffer > 0)
{
if (WSFrame.TryParse(this.receiveBuffer, 0, this.bytesInBuffer, this.options.MaxReceiveFrameLength, out this.lastRcvdFrame) == true)
{
// restart activity timer
if (this.activityTimerEnabled)
{
this.activityTimer.Restart(ActivityTimerState.WaitingForMessage);
}
// remove data-frame from buffer
Array.Copy(this.receiveBuffer, this.lastRcvdFrame.FrameData.Length, this.receiveBuffer, 0, this.bytesInBuffer - this.lastRcvdFrame.FrameData.Length);
this.bytesInBuffer = this.bytesInBuffer - this.lastRcvdFrame.FrameData.Length;
// take action based on opcode
switch (this.lastRcvdFrame.OpCode)
{
case WSFrameType.Continuation:
// TODO - implement continuation frames
break;
case WSFrameType.Text:
this.LogBufferContent("Text frame received: ", this.lastRcvdFrame.FrameData, 0, this.lastRcvdFrame.FrameData.Length);
this.OnTextReceived(this.lastRcvdFrame.PayloadText);
break;
case WSFrameType.Binary:
this.LogBufferContent("Data frame received: ", this.lastRcvdFrame.FrameData, 0, this.lastRcvdFrame.FrameData.Length);
this.OnDataReceived(this.lastRcvdFrame.PayloadBytes);
break;
case WSFrameType.Close:
this.LogBufferContent("Close frame received: ", this.lastRcvdFrame.FrameData, 0, this.lastRcvdFrame.FrameData.Length);
// based on RFC6455 we must stop sending and receiving messages after Close response is sent
this.activityTimer.Stop();
this.state = WebSocketState.Disconnecting;
this.subState = SubState.SendCloseResponse;
return;
case WSFrameType.Ping:
this.LogBufferContent("Ping frame received: ", this.lastRcvdFrame.FrameData, 0, this.lastRcvdFrame.FrameData.Length);
this.DoSendPongMessage();
break;
case WSFrameType.Pong:
this.LogBufferContent("Pong frame received: ", this.lastRcvdFrame.FrameData, 0, this.lastRcvdFrame.FrameData.Length);
// no need to do anything
break;
default:
this.LogBufferContent("Unknown frame received: ", this.lastRcvdFrame.FrameData, 0, this.lastRcvdFrame.FrameData.Length);
break;
}
}
}
// send queued messages
if (this.DequeueAndSendMessages() && this.activityTimerEnabled)
{
this.activityTimer.Restart(ActivityTimerState.MessageSent);
}
// get more data
if (this.socket.Poll(this.waitReceiveTimeout, SelectMode.SelectRead) == true && this.socket.Available > 0)
{
int bytesRead = this.socketStream.Read(this.receiveBuffer, this.bytesInBuffer, this.receiveBuffer.Length - this.bytesInBuffer);
this.bytesInBuffer += bytesRead;
if (bytesRead > 0)
{
this.activityTimer.Restart(ActivityTimerState.WaitingForMessage);
}
}
// check activity timer
if (this.activityTimerEnabled && this.activityTimer.HasTimedOut)
{
switch ((ActivityTimerState)this.activityTimer.State)
{
case ActivityTimerState.MessageSent:
case ActivityTimerState.WaitingForMessage:
this.DoSendPingMessage();
activityTimer.Restart(ActivityTimerState.WaitingForPingResponse);
break;
case ActivityTimerState.WaitingForPingResponse:
Logger.WriteError(this.loggerID, string.Concat("Ping response timed out."));
activityTimer.Stop();
this.subState = SubState.Failed;
break;
}
}
}
