private static async Task <HttpListenerWebSocketContext> AcceptWebSocketAsyncCore(HttpListenerContext context,
string subProtocol,
int receiveBufferSize,
TimeSpan keepAliveInterval,
ArraySegment <byte> internalBuffer)
{
HttpListenerWebSocketContext webSocketContext = null;
if (Logging.On)
{
Logging.Enter(Logging.WebSockets, context, "AcceptWebSocketAsync", "");
}
try
{
// get property will create a new response if one doesn't exist.
HttpListenerResponse response = context.Response;
HttpListenerRequest request = context.Request;
ValidateWebSocketHeaders(context);
string secWebSocketVersion = request.Headers[HttpKnownHeaderNames.SecWebSocketVersion];
// Optional for non-browser client
string origin = request.Headers[HttpKnownHeaderNames.Origin];
List <string> secWebSocketProtocols = new List <string>();
string outgoingSecWebSocketProtocolString;
bool shouldSendSecWebSocketProtocolHeader =
WebSocketHelpers.ProcessWebSocketProtocolHeader(
request.Headers[HttpKnownHeaderNames.SecWebSocketProtocol],
subProtocol,
out outgoingSecWebSocketProtocolString);
if (shouldSendSecWebSocketProtocolHeader)
{
secWebSocketProtocols.Add(outgoingSecWebSocketProtocolString);
response.Headers.Add(HttpKnownHeaderNames.SecWebSocketProtocol,
outgoingSecWebSocketProtocolString);
}
// negotiate the websocket key return value
string secWebSocketKey = request.Headers[HttpKnownHeaderNames.SecWebSocketKey];
string secWebSocketAccept = WebSocketHelpers.GetSecWebSocketAcceptString(secWebSocketKey);
response.Headers.Add(HttpKnownHeaderNames.Connection, HttpKnownHeaderNames.Upgrade);
response.Headers.Add(HttpKnownHeaderNames.Upgrade, WebSocketHelpers.WebSocketUpgradeToken);
response.Headers.Add(HttpKnownHeaderNames.SecWebSocketAccept, secWebSocketAccept);
response.StatusCode = (int)HttpStatusCode.SwitchingProtocols; // HTTP 101
response.ComputeCoreHeaders();
ulong hresult = SendWebSocketHeaders(response);
if (hresult != 0)
{
throw new WebSocketException((int)hresult,
SR.GetString(SR.net_WebSockets_NativeSendResponseHeaders,
WebSocketHelpers.MethodNames.AcceptWebSocketAsync,
hresult));
}
if (Logging.On)
{
Logging.PrintInfo(Logging.WebSockets, string.Format("{0} = {1}",
HttpKnownHeaderNames.Origin, origin));
Logging.PrintInfo(Logging.WebSockets, string.Format("{0} = {1}",
HttpKnownHeaderNames.SecWebSocketVersion, secWebSocketVersion));
Logging.PrintInfo(Logging.WebSockets, string.Format("{0} = {1}",
HttpKnownHeaderNames.SecWebSocketKey, secWebSocketKey));
Logging.PrintInfo(Logging.WebSockets, string.Format("{0} = {1}",
HttpKnownHeaderNames.SecWebSocketAccept, secWebSocketAccept));
Logging.PrintInfo(Logging.WebSockets, string.Format("Request {0} = {1}",
HttpKnownHeaderNames.SecWebSocketProtocol,
request.Headers[HttpKnownHeaderNames.SecWebSocketProtocol]));
Logging.PrintInfo(Logging.WebSockets, string.Format("Response {0} = {1}",
HttpKnownHeaderNames.SecWebSocketProtocol, outgoingSecWebSocketProtocolString));
}
await response.OutputStream.FlushAsync().SuppressContextFlow();
HttpResponseStream responseStream = response.OutputStream as HttpResponseStream;
Contract.Assert(responseStream != null, "'responseStream' MUST be castable to System.Net.HttpResponseStream.");
((HttpResponseStream)response.OutputStream).SwitchToOpaqueMode();
HttpRequestStream requestStream = new HttpRequestStream(context);
requestStream.SwitchToOpaqueMode();
WebSocketHttpListenerDuplexStream webSocketStream =
new WebSocketHttpListenerDuplexStream(requestStream, responseStream, context);
WebSocket webSocket = WebSocket.CreateServerWebSocket(webSocketStream,
subProtocol,
receiveBufferSize,
keepAliveInterval,
internalBuffer);
webSocketContext = new HttpListenerWebSocketContext(
request.Url,
request.Headers,
request.Cookies,
context.User,
request.IsAuthenticated,
request.IsLocal,
request.IsSecureConnection,
origin,
secWebSocketProtocols.AsReadOnly(),
secWebSocketVersion,
secWebSocketKey,
webSocket);
if (Logging.On)
{
Logging.Associate(Logging.WebSockets, context, webSocketContext);
Logging.Associate(Logging.WebSockets, webSocketContext, webSocket);
}
}
catch (Exception ex)
{
if (Logging.On)
{
Logging.Exception(Logging.WebSockets, context, "AcceptWebSocketAsync", ex);
}
throw;
}
finally
{
if (Logging.On)
{
Logging.Exit(Logging.WebSockets, context, "AcceptWebSocketAsync", "");
}
}
return(webSocketContext);
}