internal static byte[] CreateOpenningHandshakeResponse(AsyncWebSocketSession session, string secWebSocketKey)
{
var sb = new StringBuilder();
// A Status-Line with a 101 response code as per RFC 2616
// [RFC2616]. Such a response could look like "HTTP/1.1 101 Switching Protocols".
sb.AppendFormatWithCrCf("HTTP/{0} {1} {2}",
Consts.HttpVersion,
(int)HttpStatusCode.SwitchingProtocols,
@"Switching Protocols");
// An |Upgrade| header field with value "websocket" as per RFC2616 [RFC2616].
sb.AppendFormatWithCrCf(Consts.HeaderLineFormat, HttpKnownHeaderNames.Upgrade, Consts.WebSocketUpgradeToken);
// A |Connection| header field with value "Upgrade".
sb.AppendFormatWithCrCf(Consts.HeaderLineFormat, HttpKnownHeaderNames.Connection, Consts.WebSocketConnectionToken);
// A |Sec-WebSocket-Accept| header field. The value of this
// header field is constructed by concatenating /key/, defined
// above in step 4 in Section 4.2.2, with the string "258EAFA5-
// E914-47DA-95CA-C5AB0DC85B11", taking the SHA-1 hash of this
// concatenated value to obtain a 20-byte value and base64-
// encoding (see Section 4 of [RFC4648]) this 20-byte hash.
var secWebSocketAccept = GetSecWebSocketAcceptString(secWebSocketKey);
sb.AppendFormatWithCrCf(Consts.HeaderLineFormat, HttpKnownHeaderNames.SecWebSocketAccept, secWebSocketAccept);
// Optionally, a |Sec-WebSocket-Extensions| header field, with a
// value /extensions/ as defined in step 4 in Section 4.2.2. If
// multiple extensions are to be used, they can all be listed in
// a single |Sec-WebSocket-Extensions| header field or split
// between multiple instances of the |Sec-WebSocket-Extensions| header field.
// A server accepts one or more extensions by including a
// |Sec-WebSocket-Extensions| header field containing one or more
// extensions that were requested by the client. The interpretation of
// any extension parameters, and what constitutes a valid response by a
// server to a requested set of parameters by a client, will be defined
// by each such extension.
if (session.NegotiatedExtensions != null && session.NegotiatedExtensions.Any())
{
foreach (var extension in session.NegotiatedExtensions.Values)
{
var offer = extension.GetAgreedOffer();
sb.AppendFormatWithCrCf(Consts.HeaderLineFormat, HttpKnownHeaderNames.SecWebSocketExtensions, offer);
}
}
/**
// Optionally, a |Sec-WebSocket-Protocol| header field, with a
// value /subprotocol/ as defined in step 4 in Section 4.2.2.
//
// The client can request that the server use a specific subprotocol by
// including the |Sec-WebSocket-Protocol| field in its handshake. If it
// is specified, the server needs to include the same field and one of
// the selected subprotocol values in its response for the connection to
// be established.
//
// These subprotocol names should be registered as per Section 11.5. To
// avoid potential collisions, it is recommended to use names that
// contain the ASCII version of the domain name of the subprotocol's
// originator. For example, if Example Corporation were to create a
// Chat subprotocol to be implemented by many servers around the Web,
// they could name it "chat.example.com". If the Example Organization
// called their competing subprotocol "chat.example.org", then the two
// subprotocols could be implemented by servers simultaneously, with the
// server dynamically selecting which subprotocol to use based on the
// value sent by the client.
//
// Subprotocols can be versioned in backward-incompatible ways by
// changing the subprotocol name, e.g., going from
// "bookings.example.net" to "v2.bookings.example.net". These
// subprotocols would be considered completely separate by WebSocket
// clients. Backward-compatible versioning can be implemented by
// reusing the same subprotocol string but carefully designing the
// actual subprotocol to support this kind of extensibility.
*/
sb.AppendWithCrCf();
// HTTP/1.1 101 Switching Protocols
// Upgrade: websocket
// Connection: Upgrade
// Sec-WebSocket-Accept: 1tGBmA9p0DQDgmFll6P0/UcVS/E=
// Sec-WebSocket-Protocol: chat
var response = sb.ToString();
#if DEBUG
_log.DebugFormat("[{0}]{1}{2}", session.RemoteEndPoint, Environment.NewLine, response);
#endif
return Encoding.UTF8.GetBytes(response);
}
internal static byte[] CreateOpenningHandshakeBadRequestResponse(AsyncWebSocketSession session)
{
var sb = new StringBuilder();
// HTTP/1.1 400 Bad Request
sb.AppendFormatWithCrCf("HTTP/{0} {1} {2}",
Consts.HttpVersion,
(int)HttpStatusCode.BadRequest,
@"Bad Request");
// Upgrade: websocket
sb.AppendFormatWithCrCf(Consts.HeaderLineFormat, HttpKnownHeaderNames.Upgrade, Consts.WebSocketUpgradeToken);
// Connection: Upgrade
sb.AppendFormatWithCrCf(Consts.HeaderLineFormat, HttpKnownHeaderNames.Connection, Consts.WebSocketConnectionToken);
// Sec-WebSocket-Version: 13
sb.AppendFormatWithCrCf(Consts.HeaderLineFormat, HttpKnownHeaderNames.SecWebSocketVersion, Consts.WebSocketVersion);
sb.AppendWithCrCf();
var response = sb.ToString();
#if DEBUG
_log.DebugFormat("[{0}]{1}{2}", session.RemoteEndPoint, Environment.NewLine, response);
#endif
return Encoding.UTF8.GetBytes(response);
}
public virtual async Task OnSessionFragmentationStreamClosed(AsyncWebSocketSession session, byte[] data, int offset, int count)
{
await Task.CompletedTask;
}
internal static bool HandleOpenningHandshakeRequest(AsyncWebSocketSession session, byte[] buffer, int offset, int count,
out string secWebSocketKey,
out string path,
out string query)
{
BufferValidator.ValidateBuffer(buffer, offset, count, "buffer");
var request = Encoding.UTF8.GetString(buffer, offset, count);
#if DEBUG
_log.DebugFormat("[{0}]{1}{2}", session.RemoteEndPoint, Environment.NewLine, request);
#endif
try
{
// GET /chat HTTP/1.1
// Host: server.example.com
// Upgrade: websocket
// Connection: Upgrade
// Sec-WebSocket-Key: dGhlIHNhbXBsZSBub25jZQ==
// Origin: http://example.com
// Sec-WebSocket-Protocol: chat, superchat
// Sec-WebSocket-Version: 13
Dictionary<string, string> headers;
List<string> extensions;
List<string> protocols;
ParseOpenningHandshakeRequestHeaders(request, out headers, out extensions, out protocols);
if (headers == null)
throw new WebSocketHandshakeException(string.Format(
"Handshake with remote [{0}] failed due to invalid headers.", session.RemoteEndPoint));
// An HTTP/1.1 or higher GET request, including a "Request-URI"
// [RFC2616] that should be interpreted as a /resource name/
// defined in Section 3 (or an absolute HTTP/HTTPS URI containing the /resource name/).
// A |Host| header field containing the server's authority.
if (!headers.ContainsKey(Consts.HttpGetMethodName))
throw new WebSocketHandshakeException(string.Format(
"Handshake with remote [{0}] failed due to lack of get method.", session.RemoteEndPoint));
if (!headers.ContainsKey(HttpKnownHeaderNames.Host))
throw new WebSocketHandshakeException(string.Format(
"Handshake with remote [{0}] failed due to lack of host authority.", session.RemoteEndPoint));
string uriString = string.Format("ws://{0}{1}", headers[HttpKnownHeaderNames.Host], headers[Consts.HttpGetMethodName]);
Uri requestUri = null;
if (!Uri.TryCreate(uriString, UriKind.RelativeOrAbsolute, out requestUri))
{
throw new WebSocketHandshakeException(string.Format(
"Handshake with remote [{0}] failed due to invalid requested resource name.", session.RemoteEndPoint));
}
path = requestUri.AbsolutePath;
query = requestUri.Query;
// A |Connection| header field that includes the token "Upgrade",
// treated as an ASCII case-insensitive value.
if (!headers.ContainsKey(HttpKnownHeaderNames.Connection))
throw new WebSocketHandshakeException(string.Format(
"Handshake with remote [{0}] failed due to lack of connection header item.", session.RemoteEndPoint));
if (headers[HttpKnownHeaderNames.Connection].ToLowerInvariant() != Consts.WebSocketConnectionToken.ToLowerInvariant())
throw new WebSocketHandshakeException(string.Format(
"Handshake with remote [{0}] failed due to invalid connection header item value [{1}].",
session.RemoteEndPoint, headers[HttpKnownHeaderNames.Connection]));
// An |Upgrade| header field containing the value "websocket",
// treated as an ASCII case-insensitive value.
if (!headers.ContainsKey(HttpKnownHeaderNames.Upgrade))
throw new WebSocketHandshakeException(string.Format(
"Handshake with remote [{0}] failed due to lack of upgrade header item.", session.RemoteEndPoint));
if (headers[HttpKnownHeaderNames.Upgrade].ToLowerInvariant() != Consts.WebSocketUpgradeToken.ToLowerInvariant())
throw new WebSocketHandshakeException(string.Format(
"Handshake with remote [{0}] failed due to invalid upgrade header item value [{1}].",
session.RemoteEndPoint, headers[HttpKnownHeaderNames.Upgrade]));
// A |Sec-WebSocket-Key| header field with a base64-encoded (see
// Section 4 of [RFC4648]) value that, when decoded, is 16 bytes in length.
if (!headers.ContainsKey(HttpKnownHeaderNames.SecWebSocketKey))
throw new WebSocketHandshakeException(string.Format(
"Handshake with remote [{0}] failed due to lack of Sec-WebSocket-Key header item.", session.RemoteEndPoint));
if (string.IsNullOrWhiteSpace(headers[HttpKnownHeaderNames.SecWebSocketKey]))
throw new WebSocketHandshakeException(string.Format(
"Handshake with remote [{0}] failed due to invalid Sec-WebSocket-Key header item value [{1}].",
session.RemoteEndPoint, headers[HttpKnownHeaderNames.SecWebSocketKey]));
secWebSocketKey = headers[HttpKnownHeaderNames.SecWebSocketKey];
// A |Sec-WebSocket-Version| header field, with a value of 13.
if (!headers.ContainsKey(HttpKnownHeaderNames.SecWebSocketVersion))
throw new WebSocketHandshakeException(string.Format(
"Handshake with remote [{0}] failed due to lack of Sec-WebSocket-Version header item.", session.RemoteEndPoint));
if (headers[HttpKnownHeaderNames.SecWebSocketVersion].ToLowerInvariant() != Consts.WebSocketVersion.ToLowerInvariant())
throw new WebSocketHandshakeException(string.Format(
"Handshake with remote [{0}] failed due to invalid Sec-WebSocket-Version header item value [{1}].",
session.RemoteEndPoint, headers[HttpKnownHeaderNames.SecWebSocketVersion]));
// Optionally, a |Sec-WebSocket-Extensions| header field, with a
// list of values indicating which extensions the client would like
// to speak. The interpretation of this header field is discussed in Section 9.1.
if (extensions != null)
{
if (!extensions.Any())
throw new WebSocketHandshakeException(string.Format(
"Handshake with remote [{0}] failed due to empty extension.", session.RemoteEndPoint));
foreach (var extension in extensions)
{
// The empty string is not the same as the null value for these
// purposes and is not a legal value for this field.
if (string.IsNullOrWhiteSpace(extension))
throw new WebSocketHandshakeException(string.Format(
"Handshake with remote [{0}] failed due to empty extension.", session.RemoteEndPoint));
}
session.AgreeExtensions(extensions);
}
// Optionally, a |Sec-WebSocket-Protocol| header field, with a list
// of values indicating which protocols the client would like to
// speak, ordered by preference.
if (protocols != null)
{
if (!protocols.Any())
throw new WebSocketHandshakeException(string.Format(
"Handshake with remote [{0}] failed due to empty sub-protocol.", session.RemoteEndPoint));
foreach (var protocol in protocols)
{
// The empty string is not the same as the null value for these
// purposes and is not a legal value for this field.
if (string.IsNullOrWhiteSpace(protocol))
throw new WebSocketHandshakeException(string.Format(
"Handshake with remote [{0}] failed due to empty sub-protocol.", session.RemoteEndPoint));
}
session.AgreeSubProtocols(string.Join(",", protocols));
}
// Optionally, an |Origin| header field. This header field is sent
// by all browser clients. A connection attempt lacking this
// header field SHOULD NOT be interpreted as coming from a browser client.
//
// Servers that are not intended to process input from any web page but
// only for certain sites SHOULD verify the |Origin| field is an origin
// they expect. If the origin indicated is unacceptable to the server,
// then it SHOULD respond to the WebSocket handshake with a reply
// containing HTTP 403 Forbidden status code.
//
// The |Origin| header field protects from the attack cases when the
// untrusted party is typically the author of a JavaScript application
// that is executing in the context of the trusted client. The client
// itself can contact the server and, via the mechanism of the |Origin|
// header field, determine whether to extend those communication
// privileges to the JavaScript application. The intent is not to
// prevent non-browsers from establishing connections but rather to
// ensure that trusted browsers under the control of potentially
// malicious JavaScript cannot fake a WebSocket handshake.
// Optionally, other header fields, such as those used to send
// cookies or request authentication to a server. Unknown header
// fields are ignored, as per [RFC2616].
}
catch (Exception ex)
{
_log.ErrorFormat("{0}{1}{2}", session, Environment.NewLine, request);
_log.Error(ex.Message, ex);
throw;
}
return true;
}
private async Task Process(TcpClient acceptedTcpClient)
{
var session = new AsyncWebSocketSession(acceptedTcpClient, _configuration, _bufferManager, _routeResolver, this);
if (_sessions.TryAdd(session.SessionKey, session))
{
_log.DebugFormat("New session [{0}].", session);
try
{
await session.Start();
}
catch (Exception ex)
when (ex is TimeoutException || ex is WebSocketException)
{
_log.Error(ex.Message, ex);
}
finally
{
AsyncWebSocketSession throwAway;
if (_sessions.TryRemove(session.SessionKey, out throwAway))
{
_log.DebugFormat("Close session [{0}].", throwAway);
}
}
}
}
public virtual async Task OnSessionClosed(AsyncWebSocketSession session)
{
AsyncWebSocketSession throwAway;
_sessions.TryRemove(session.SessionKey, out throwAway);
await Task.CompletedTask;
}
public virtual async Task OnSessionStarted(AsyncWebSocketSession session)
{
_sessions.TryAdd(session.SessionKey, session);
await Task.CompletedTask;
}
public virtual async Task OnSessionBinaryReceived(AsyncWebSocketSession session, byte[] data, int offset, int count)
{
await Task.CompletedTask;
}
internal static bool HandleOpenningHandshakeRequest(AsyncWebSocketSession session, byte[] buffer, int offset, int count,
out string secWebSocketKey,
out string path,
out string query)
{
BufferValidator.ValidateBuffer(buffer, offset, count, "buffer");
var request = Encoding.UTF8.GetString(buffer, offset, count);
#if DEBUG
_log.DebugFormat("[{0}]{1}{2}", session.RemoteEndPoint, Environment.NewLine, request);
#endif
try
{
// GET /chat HTTP/1.1
// Host: server.example.com
// Upgrade: websocket
// Connection: Upgrade
// Sec-WebSocket-Key: dGhlIHNhbXBsZSBub25jZQ==
// Origin: http://example.com
// Sec-WebSocket-Protocol: chat, superchat
// Sec-WebSocket-Version: 13
Dictionary <string, string> headers;
List <string> extensions;
List <string> protocols;
ParseOpenningHandshakeRequestHeaders(request, out headers, out extensions, out protocols);
if (headers == null)
{
throw new WebSocketHandshakeException(string.Format(
"Handshake with remote [{0}] failed due to invalid headers.", session.RemoteEndPoint));
}
// An HTTP/1.1 or higher GET request, including a "Request-URI"
// [RFC2616] that should be interpreted as a /resource name/
// defined in Section 3 (or an absolute HTTP/HTTPS URI containing the /resource name/).
// A |Host| header field containing the server's authority.
if (!headers.ContainsKey(Consts.HttpGetMethodName))
{
throw new WebSocketHandshakeException(string.Format(
"Handshake with remote [{0}] failed due to lack of get method.", session.RemoteEndPoint));
}
if (!headers.ContainsKey(HttpKnownHeaderNames.Host))
{
throw new WebSocketHandshakeException(string.Format(
"Handshake with remote [{0}] failed due to lack of host authority.", session.RemoteEndPoint));
}
string uriString = string.Format("ws://{0}{1}", headers[HttpKnownHeaderNames.Host], headers[Consts.HttpGetMethodName]);
Uri requestUri = null;
if (!Uri.TryCreate(uriString, UriKind.RelativeOrAbsolute, out requestUri))
{
throw new WebSocketHandshakeException(string.Format(
"Handshake with remote [{0}] failed due to invalid requested resource name.", session.RemoteEndPoint));
}
path = requestUri.AbsolutePath;
query = requestUri.Query;
// A |Connection| header field that includes the token "Upgrade",
// treated as an ASCII case-insensitive value.
if (!headers.ContainsKey(HttpKnownHeaderNames.Connection))
{
throw new WebSocketHandshakeException(string.Format(
"Handshake with remote [{0}] failed due to lack of connection header item.", session.RemoteEndPoint));
}
if (headers[HttpKnownHeaderNames.Connection].ToLowerInvariant() != Consts.WebSocketConnectionToken.ToLowerInvariant())
{
throw new WebSocketHandshakeException(string.Format(
"Handshake with remote [{0}] failed due to invalid connection header item value [{1}].",
session.RemoteEndPoint, headers[HttpKnownHeaderNames.Connection]));
}
// An |Upgrade| header field containing the value "websocket",
// treated as an ASCII case-insensitive value.
if (!headers.ContainsKey(HttpKnownHeaderNames.Upgrade))
{
throw new WebSocketHandshakeException(string.Format(
"Handshake with remote [{0}] failed due to lack of upgrade header item.", session.RemoteEndPoint));
}
if (headers[HttpKnownHeaderNames.Upgrade].ToLowerInvariant() != Consts.WebSocketUpgradeToken.ToLowerInvariant())
{
throw new WebSocketHandshakeException(string.Format(
"Handshake with remote [{0}] failed due to invalid upgrade header item value [{1}].",
session.RemoteEndPoint, headers[HttpKnownHeaderNames.Upgrade]));
}
// A |Sec-WebSocket-Key| header field with a base64-encoded (see
// Section 4 of [RFC4648]) value that, when decoded, is 16 bytes in length.
if (!headers.ContainsKey(HttpKnownHeaderNames.SecWebSocketKey))
{
throw new WebSocketHandshakeException(string.Format(
"Handshake with remote [{0}] failed due to lack of Sec-WebSocket-Key header item.", session.RemoteEndPoint));
}
if (string.IsNullOrWhiteSpace(headers[HttpKnownHeaderNames.SecWebSocketKey]))
{
throw new WebSocketHandshakeException(string.Format(
"Handshake with remote [{0}] failed due to invalid Sec-WebSocket-Key header item value [{1}].",
session.RemoteEndPoint, headers[HttpKnownHeaderNames.SecWebSocketKey]));
}
secWebSocketKey = headers[HttpKnownHeaderNames.SecWebSocketKey];
// A |Sec-WebSocket-Version| header field, with a value of 13.
if (!headers.ContainsKey(HttpKnownHeaderNames.SecWebSocketVersion))
{
throw new WebSocketHandshakeException(string.Format(
"Handshake with remote [{0}] failed due to lack of Sec-WebSocket-Version header item.", session.RemoteEndPoint));
}
if (headers[HttpKnownHeaderNames.SecWebSocketVersion].ToLowerInvariant() != Consts.WebSocketVersion.ToLowerInvariant())
{
throw new WebSocketHandshakeException(string.Format(
"Handshake with remote [{0}] failed due to invalid Sec-WebSocket-Version header item value [{1}].",
session.RemoteEndPoint, headers[HttpKnownHeaderNames.SecWebSocketVersion]));
}
// Optionally, a |Sec-WebSocket-Extensions| header field, with a
// list of values indicating which extensions the client would like
// to speak. The interpretation of this header field is discussed in Section 9.1.
if (extensions != null)
{
if (!extensions.Any())
{
throw new WebSocketHandshakeException(string.Format(
"Handshake with remote [{0}] failed due to empty extension.", session.RemoteEndPoint));
}
foreach (var extension in extensions)
{
// The empty string is not the same as the null value for these
// purposes and is not a legal value for this field.
if (string.IsNullOrWhiteSpace(extension))
{
throw new WebSocketHandshakeException(string.Format(
"Handshake with remote [{0}] failed due to empty extension.", session.RemoteEndPoint));
}
}
session.AgreeExtensions(extensions);
}
// Optionally, a |Sec-WebSocket-Protocol| header field, with a list
// of values indicating which protocols the client would like to
// speak, ordered by preference.
if (protocols != null)
{
if (!protocols.Any())
{
throw new WebSocketHandshakeException(string.Format(
"Handshake with remote [{0}] failed due to empty sub-protocol.", session.RemoteEndPoint));
}
foreach (var protocol in protocols)
{
// The empty string is not the same as the null value for these
// purposes and is not a legal value for this field.
if (string.IsNullOrWhiteSpace(protocol))
{
throw new WebSocketHandshakeException(string.Format(
"Handshake with remote [{0}] failed due to empty sub-protocol.", session.RemoteEndPoint));
}
}
session.AgreeSubProtocols(string.Join(",", protocols));
}
// Optionally, an |Origin| header field. This header field is sent
// by all browser clients. A connection attempt lacking this
// header field SHOULD NOT be interpreted as coming from a browser client.
//
// Servers that are not intended to process input from any web page but
// only for certain sites SHOULD verify the |Origin| field is an origin
// they expect. If the origin indicated is unacceptable to the server,
// then it SHOULD respond to the WebSocket handshake with a reply
// containing HTTP 403 Forbidden status code.
//
// The |Origin| header field protects from the attack cases when the
// untrusted party is typically the author of a JavaScript application
// that is executing in the context of the trusted client. The client
// itself can contact the server and, via the mechanism of the |Origin|
// header field, determine whether to extend those communication
// privileges to the JavaScript application. The intent is not to
// prevent non-browsers from establishing connections but rather to
// ensure that trusted browsers under the control of potentially
// malicious JavaScript cannot fake a WebSocket handshake.
// Optionally, other header fields, such as those used to send
// cookies or request authentication to a server. Unknown header
// fields are ignored, as per [RFC2616].
}
catch (Exception ex)
{
_log.ErrorFormat("{0}{1}{2}", session, Environment.NewLine, request);
_log.Error(ex.Message, ex);
throw;
}
return(true);
}
internal static byte[] CreateOpenningHandshakeResponse(AsyncWebSocketSession session, string secWebSocketKey)
{
var sb = new StringBuilder();
// A Status-Line with a 101 response code as per RFC 2616
// [RFC2616]. Such a response could look like "HTTP/1.1 101 Switching Protocols".
sb.AppendFormatWithCrCf("HTTP/{0} {1} {2}",
Consts.HttpVersion,
(int)HttpStatusCode.SwitchingProtocols,
@"Switching Protocols");
// An |Upgrade| header field with value "websocket" as per RFC2616 [RFC2616].
sb.AppendFormatWithCrCf(Consts.HttpHeaderLineFormat, HttpKnownHeaderNames.Upgrade, Consts.WebSocketUpgradeToken);
// A |Connection| header field with value "Upgrade".
sb.AppendFormatWithCrCf(Consts.HttpHeaderLineFormat, HttpKnownHeaderNames.Connection, Consts.WebSocketConnectionToken);
// A |Sec-WebSocket-Accept| header field. The value of this
// header field is constructed by concatenating /key/, defined
// above in step 4 in Section 4.2.2, with the string "258EAFA5-
// E914-47DA-95CA-C5AB0DC85B11", taking the SHA-1 hash of this
// concatenated value to obtain a 20-byte value and base64-
// encoding (see Section 4 of [RFC4648]) this 20-byte hash.
var secWebSocketAccept = GetSecWebSocketAcceptString(secWebSocketKey);
sb.AppendFormatWithCrCf(Consts.HttpHeaderLineFormat, HttpKnownHeaderNames.SecWebSocketAccept, secWebSocketAccept);
// Optionally, a |Sec-WebSocket-Extensions| header field, with a
// value /extensions/ as defined in step 4 in Section 4.2.2. If
// multiple extensions are to be used, they can all be listed in
// a single |Sec-WebSocket-Extensions| header field or split
// between multiple instances of the |Sec-WebSocket-Extensions| header field.
// A server accepts one or more extensions by including a
// |Sec-WebSocket-Extensions| header field containing one or more
// extensions that were requested by the client. The interpretation of
// any extension parameters, and what constitutes a valid response by a
// server to a requested set of parameters by a client, will be defined
// by each such extension.
if (session.NegotiatedExtensions != null && session.NegotiatedExtensions.Any())
{
foreach (var extension in session.NegotiatedExtensions.Values)
{
var offer = extension.GetAgreedOffer();
sb.AppendFormatWithCrCf(Consts.HttpHeaderLineFormat, HttpKnownHeaderNames.SecWebSocketExtensions, offer);
}
}
/**
* // Optionally, a |Sec-WebSocket-Protocol| header field, with a
* // value /subprotocol/ as defined in step 4 in Section 4.2.2.
* //
* // The client can request that the server use a specific subprotocol by
* // including the |Sec-WebSocket-Protocol| field in its handshake. If it
* // is specified, the server needs to include the same field and one of
* // the selected subprotocol values in its response for the connection to
* // be established.
* //
* // These subprotocol names should be registered as per Section 11.5. To
* // avoid potential collisions, it is recommended to use names that
* // contain the ASCII version of the domain name of the subprotocol's
* // originator. For example, if Example Corporation were to create a
* // Chat subprotocol to be implemented by many servers around the Web,
* // they could name it "chat.example.com". If the Example Organization
* // called their competing subprotocol "chat.example.org", then the two
* // subprotocols could be implemented by servers simultaneously, with the
* // server dynamically selecting which subprotocol to use based on the
* // value sent by the client.
* //
* // Subprotocols can be versioned in backward-incompatible ways by
* // changing the subprotocol name, e.g., going from
* // "bookings.example.net" to "v2.bookings.example.net". These
* // subprotocols would be considered completely separate by WebSocket
* // clients. Backward-compatible versioning can be implemented by
* // reusing the same subprotocol string but carefully designing the
* // actual subprotocol to support this kind of extensibility.
*/
sb.AppendWithCrCf();
// HTTP/1.1 101 Switching Protocols
// Upgrade: websocket
// Connection: Upgrade
// Sec-WebSocket-Accept: 1tGBmA9p0DQDgmFll6P0/UcVS/E=
// Sec-WebSocket-Protocol: chat
var response = sb.ToString();
#if DEBUG
_log.DebugFormat("[{0}]{1}{2}", session.RemoteEndPoint, Environment.NewLine, response);
#endif
return(Encoding.UTF8.GetBytes(response));
}
public async Task SendBinaryToAsync(AsyncWebSocketSession session, byte[] data, int offset, int count)
{
AsyncWebSocketSession sessionFound;
if (_sessions.TryGetValue(session.SessionKey, out sessionFound))
{
await sessionFound.SendBinaryAsync(data, offset, count);
}
else
{
_log.WarnFormat("Cannot find session [{0}].", session);
}
}
public async Task SendBinaryToAsync(AsyncWebSocketSession session, byte[] data)
{
await SendBinaryToAsync(session, data, 0, data.Length);
}
public async Task SendTextToAsync(AsyncWebSocketSession session, string text)
{
AsyncWebSocketSession sessionFound;
if (_sessions.TryGetValue(session.SessionKey, out sessionFound))
{
await sessionFound.SendTextAsync(text);
}
else
{
_log.WarnFormat("Cannot find session [{0}].", session);
}
}
public virtual async Task OnSessionStarted(AsyncWebSocketSession session)
{
_sessions.TryAdd(session.SessionKey, session);
await Task.CompletedTask;
}
public virtual async Task OnSessionTextReceived(AsyncWebSocketSession session, string text)
{
await Task.CompletedTask;
}
public virtual async Task OnSessionTextReceived(AsyncWebSocketSession session, string text)
{
await Task.CompletedTask;
}
public virtual async Task OnSessionBinaryReceived(AsyncWebSocketSession session, byte[] data, int offset, int count)
{
await Task.CompletedTask;
}
public virtual async Task OnSessionFragmentationStreamClosed(AsyncWebSocketSession session, byte[] data, int offset, int count)
{
await Task.CompletedTask;
}
public async Task SendBinaryToAsync(AsyncWebSocketSession session, byte[] data)
{
await SendBinaryToAsync(session, data, 0, data.Length);
}