public async Task SendAsync(byte[] data, WebsockOpCode opcode = WebsockOpCode.Text)
{
WebsockFrame frame = new WebsockFrame();
frame.Fin = true;
frame.Data = data;
frame.Masked = true;
frame.Opcode = opcode;
byte[] frameData = frame.Dump();
await stream.WriteAsync(frameData, frameData.Length);
}
// Deny client with http error message
private async Task <bool> RejectClient(ConnectionStream stream, string errorMessage)
{
byte[] errorData = Encoding.UTF8.GetBytes(HttpErrorTemplate
.Replace("{Content}", errorMessage)
.Replace("{ContentType}", "text/plain")
.Replace("{ContentLength}", errorMessage.Length.ToString()));
await stream.WriteAsync(errorData, errorData.Length);
stream.Dispose();
return(false);
}
private async Task <bool> Handshake(ConnectionStream stream, Uri uri, int port)
{
state = WebsockState.Connecting;
string handshakeData = HttpHandshakeData
.Replace("{Path}", uri.PathAndQuery)
.Replace("{Host}", uri.Host)
.Replace("{Scheme}", uri.Scheme)
.Replace("{Port}", port.ToString())
.Replace("{Key}", GenerateKey());
await stream.WriteAsync(handshakeData);
string response = Encoding.UTF8.GetString(await stream.ReadAsync());
return(response.Split('\n')[0].Split(' ')[1] == "101");
}
// Perform websocket handshake with client
private async Task <bool> HandshakeClient(ConnectionStream stream)
{
// read and parse http request data
byte[] httpData = await stream.ReadAsync();
HttpPacket packet = new HttpPacket(httpData);
// client requests checks
if (!packet.Method.ToLower().StartsWith("get"))
{
return(await RejectClient(stream, "Only allows GET Requests"));
}
if (!packet.Headers.ContainsKey("Sec-WebSocket-Key"))
{
return(await RejectClient(stream, "No WebSocket-Key found"));
}
if (!packet.Headers.ContainsKey("Upgrade"))
{
return(await RejectClient(stream, "Upgrade header not set"));
}
else if (!packet.Headers["Upgrade"].ToLower().StartsWith("websocket"))
{
return(await RejectClient(stream, "Upgrade header not websocket"));
}
if (!packet.Headers.ContainsKey("Connection"))
{
return(await RejectClient(stream, "Connection header not set"));
}
else if (!packet.Headers["Connection"].ToLower().StartsWith("upgrade"))
{
return(await RejectClient(stream, "Connection header not upgrade"));
}
// generate websocket key, send response to client and complete handshake
httpData = Encoding.UTF8.GetBytes(HttpHandshakeSucces.Replace(
"{WebsockKey}", GenerateKey(packet.Headers["Sec-WebSocket-Key"])));
await stream.WriteAsync(httpData, httpData.Length);
return(true);
}
