public BinaryFrame(byte[] data, int offset, int count, bool isMasked = true)
{
BufferValidator.ValidateBuffer(data, offset, count, "data");
this.Data = data;
this.Offset = offset;
this.Count = count;
this.IsMasked = isMasked;
}
public BinaryFragmentationFrame(OpCode opCode, byte[] data, int offset, int count, bool isFin = false, bool isMasked = true)
{
BufferValidator.ValidateBuffer(data, offset, count, "data");
_opCode = opCode;
this.Data = data;
this.Offset = offset;
this.Count = count;
this.IsFin = isFin;
this.IsMasked = isMasked;
}
internal static bool VerifyOpenningHandshakeResponse(AsyncWebSocketClient client, byte[] buffer, int offset, int count, string secWebSocketKey)
{
BufferValidator.ValidateBuffer(buffer, offset, count, "buffer");
if (string.IsNullOrEmpty(secWebSocketKey))
{
throw new ArgumentNullException("secWebSocketKey");
}
var response = Encoding.UTF8.GetString(buffer, offset, count);
#if DEBUG
_log.DebugFormat("[{0}]{1}{2}", client.RemoteEndPoint, Environment.NewLine, response);
#endif
try
{
// HTTP/1.1 101 Switching Protocols
// Upgrade: websocket
// Connection: Upgrade
// Sec-WebSocket-Accept: 1tGBmA9p0DQDgmFll6P0/UcVS/E=
// Sec-WebSocket-Protocol: chat
Dictionary <string, string> headers;
List <string> extensions;
List <string> protocols;
ParseOpenningHandshakeResponseHeaders(response, out headers, out extensions, out protocols);
if (headers == null)
{
throw new WebSocketHandshakeException(string.Format(
"Handshake with remote [{0}] failed due to invalid headers.", client.RemoteEndPoint));
}
// If the status code received from the server is not 101, the
// client handles the response per HTTP [RFC2616] procedures. In
// particular, the client might perform authentication if it
// receives a 401 status code; the server might redirect the client
// using a 3xx status code (but clients are not required to follow them), etc.
if (!headers.ContainsKey(Consts.HttpStatusCodeName))
{
throw new WebSocketHandshakeException(string.Format(
"Handshake with remote [{0}] failed due to lack of status code.", client.RemoteEndPoint));
}
if (!headers.ContainsKey(Consts.HttpStatusCodeDescription))
{
throw new WebSocketHandshakeException(string.Format(
"Handshake with remote [{0}] failed due to lack of status description.", client.RemoteEndPoint));
}
if (headers[Consts.HttpStatusCodeName] == ((int)HttpStatusCode.BadRequest).ToString())
{
throw new WebSocketHandshakeException(string.Format(
"Handshake with remote [{0}] failed due to bad request [{1}].",
client.RemoteEndPoint, headers[Consts.HttpStatusCodeName]));
}
if (headers[Consts.HttpStatusCodeName] != ((int)HttpStatusCode.SwitchingProtocols).ToString())
{
throw new WebSocketHandshakeException(string.Format(
"Handshake with remote [{0}] failed due to expected 101 Switching Protocols but received [{1}].",
client.RemoteEndPoint, headers[Consts.HttpStatusCodeName]));
}
// If the response lacks an |Upgrade| header field or the |Upgrade|
// header field contains a value that is not an ASCII case-
// insensitive match for the value "websocket", the client MUST
// _Fail the WebSocket Connection_.
if (!headers.ContainsKey(HttpKnownHeaderNames.Connection))
{
throw new WebSocketHandshakeException(string.Format(
"Handshake with remote [{0}] failed due to lack of connection header item.", client.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}].",
client.RemoteEndPoint, headers[HttpKnownHeaderNames.Connection]));
}
// If the response lacks a |Connection| header field or the
// |Connection| header field doesn't contain a token that is an
// ASCII case-insensitive match for the value "Upgrade", the client
// MUST _Fail the WebSocket Connection_.
if (!headers.ContainsKey(HttpKnownHeaderNames.Upgrade))
{
throw new WebSocketHandshakeException(string.Format(
"Handshake with remote [{0}] failed due to lack of upgrade header item.", client.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}].",
client.RemoteEndPoint, headers[HttpKnownHeaderNames.Upgrade]));
}
// If the response lacks a |Sec-WebSocket-Accept| header field or
// the |Sec-WebSocket-Accept| contains a value other than the
// base64-encoded SHA-1 of the concatenation of the |Sec-WebSocket-
// Key| (as a string, not base64-decoded) with the string "258EAFA5-
// E914-47DA-95CA-C5AB0DC85B11" but ignoring any leading and
// trailing whitespace, the client MUST _Fail the WebSocket Connection_.
if (!headers.ContainsKey(HttpKnownHeaderNames.SecWebSocketAccept))
{
throw new WebSocketHandshakeException(string.Format(
"Handshake with remote [{0}] failed due to lack of Sec-WebSocket-Accept header item.", client.RemoteEndPoint));
}
string challenge = GetSecWebSocketAcceptString(secWebSocketKey);
if (!headers[HttpKnownHeaderNames.SecWebSocketAccept].Equals(challenge, StringComparison.OrdinalIgnoreCase))
{
throw new WebSocketHandshakeException(string.Format(
"Handshake with remote [{0}] failed due to invalid Sec-WebSocket-Accept header item value [{1}].",
client.RemoteEndPoint, headers[HttpKnownHeaderNames.SecWebSocketAccept]));
}
// If the response includes a |Sec-WebSocket-Extensions| header
// field and this header field indicates the use of an extension
// that was not present in the client's handshake (the server has
// indicated an extension not requested by the client), the client
// MUST _Fail the WebSocket Connection_.
if (extensions != null)
{
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.", client.RemoteEndPoint));
}
}
client.AgreeExtensions(extensions);
}
// If the response includes a |Sec-WebSocket-Protocol| header field
// and this header field indicates the use of a subprotocol that was
// not present in the client's handshake (the server has indicated a
// subprotocol not requested by the client), the client MUST _Fail
// the WebSocket Connection_.
if (protocols != null)
{
if (!protocols.Any())
{
throw new WebSocketHandshakeException(string.Format(
"Handshake with remote [{0}] failed due to empty sub-protocol.", client.RemoteEndPoint));
}
if (protocols.Count > 1)
{
throw new WebSocketHandshakeException(string.Format(
"Handshake with remote [{0}] failed due to suggest to use multiple sub-protocols.", client.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.", client.RemoteEndPoint));
}
}
var suggestedProtocols = protocols.First().Split(',')
.Select(p => p.TrimStart().TrimEnd()).Where(p => !string.IsNullOrWhiteSpace(p));
if (!suggestedProtocols.Any())
{
throw new WebSocketHandshakeException(string.Format(
"Handshake with remote [{0}] failed due to invalid sub-protocol.", client.RemoteEndPoint));
}
if (suggestedProtocols.Count() > 1)
{
throw new WebSocketHandshakeException(string.Format(
"Handshake with remote [{0}] failed due to suggest to use multiple sub-protocols.", client.RemoteEndPoint));
}
// The value chosen MUST be derived
// from the client's handshake, specifically by selecting one of
// the values from the |Sec-WebSocket-Protocol| field that the
// server is willing to use for this connection (if any).
client.UseSubProtocol(suggestedProtocols.First());
}
}
catch (Exception ex)
{
_log.ErrorFormat("{0}{1}{2}", client, Environment.NewLine, response);
_log.Error(ex.Message, ex);
throw;
}
return(true);
}
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 bool VerifyOpenningHandshakeResponse(WebSocketClient client, byte[] buffer, int offset, int count, string secWebSocketKey)
{
BufferValidator.ValidateBuffer(buffer, offset, count, "buffer");
if (string.IsNullOrEmpty(secWebSocketKey))
{
throw new ArgumentNullException("secWebSocketKey");
}
var response = Encoding.UTF8.GetString(buffer, offset, count);
try
{
// HTTP/1.1 101 Switching Protocols
// Upgrade: websocket
// Connection: Upgrade
// Sec-WebSocket-Accept: 1tGBmA9p0DQDgmFll6P0/UcVS/E=
// Sec-WebSocket-Protocol: chat
Dictionary <string, string> headers;
List <string> extensions;
List <string> protocols;
ParseOpenningHandshakeResponseHeaders(response, out headers, out extensions, out protocols);
if (headers == null)
{
throw new WebSocketHandshakeException(string.Format(
"Handshake with remote [{0}] failed due to invalid headers.", client.RemoteEndPoint));
}
// If the status code received from the server is not 101, the
// client handles the response per HTTP [RFC2616] procedures. In
// particular, the client might perform authentication if it
// receives a 401 status code; the server might redirect the client
// using a 3xx status code (but clients are not required to follow them), etc.
if (!headers.ContainsKey(Consts.HttpStatusCodeName))
{
throw new WebSocketHandshakeException(string.Format(
"Handshake with remote [{0}] failed due to lack of status code.", client.RemoteEndPoint));
}
if (!headers.ContainsKey(Consts.HttpStatusCodeDescription))
{
throw new WebSocketHandshakeException(string.Format(
"Handshake with remote [{0}] failed due to lack of status description.", client.RemoteEndPoint));
}
if (headers[Consts.HttpStatusCodeName] == ((int)HttpStatusCode.BadRequest).ToString())
{
throw new WebSocketHandshakeException(string.Format(
"Handshake with remote [{0}] failed due to bad request [{1}].",
client.RemoteEndPoint, headers[Consts.HttpStatusCodeName]));
}
if (headers[Consts.HttpStatusCodeName] != ((int)HttpStatusCode.SwitchingProtocols).ToString())
{
throw new WebSocketHandshakeException(string.Format(
"Handshake with remote [{0}] failed due to expected 101 Switching Protocols but received [{1}].",
client.RemoteEndPoint, headers[Consts.HttpStatusCodeName]));
}
// If the response lacks an |Upgrade| header field or the |Upgrade|
// header field contains a value that is not an ASCII case-
// insensitive match for the value "websocket", the client MUST
// _Fail the WebSocket Connection_.
if (!headers.ContainsKey(HttpKnownHeaderNames.Connection))
{
throw new WebSocketHandshakeException(string.Format(
"Handshake with remote [{0}] failed due to lack of connection header item.", client.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}].",
client.RemoteEndPoint, headers[HttpKnownHeaderNames.Connection]));
}
// If the response lacks a |Connection| header field or the
// |Connection| header field doesn't contain a token that is an
// ASCII case-insensitive match for the value "Upgrade", the client
// MUST _Fail the WebSocket Connection_.
if (!headers.ContainsKey(HttpKnownHeaderNames.Upgrade))
{
throw new WebSocketHandshakeException(string.Format(
"Handshake with remote [{0}] failed due to lack of upgrade header item.", client.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}].",
client.RemoteEndPoint, headers[HttpKnownHeaderNames.Upgrade]));
}
// If the response lacks a |Sec-WebSocket-Accept| header field or
// the |Sec-WebSocket-Accept| contains a value other than the
// base64-encoded SHA-1 of the concatenation of the |Sec-WebSocket-
// Key| (as a string, not base64-decoded) with the string "258EAFA5-
// E914-47DA-95CA-C5AB0DC85B11" but ignoring any leading and
// trailing whitespace, the client MUST _Fail the WebSocket Connection_.
if (!headers.ContainsKey(HttpKnownHeaderNames.SecWebSocketAccept))
{
throw new WebSocketHandshakeException(string.Format(
"Handshake with remote [{0}] failed due to lack of Sec-WebSocket-Accept header item.", client.RemoteEndPoint));
}
string challenge = GetSecWebSocketAcceptString(secWebSocketKey);
if (!headers[HttpKnownHeaderNames.SecWebSocketAccept].Equals(challenge, StringComparison.OrdinalIgnoreCase))
{
throw new WebSocketHandshakeException(string.Format(
"Handshake with remote [{0}] failed due to invalid Sec-WebSocket-Accept header item value [{1}].",
client.RemoteEndPoint, headers[HttpKnownHeaderNames.SecWebSocketAccept]));
}
// If the response includes a |Sec-WebSocket-Extensions| header
// field and this header field indicates the use of an extension
// that was not present in the client's handshake (the server has
// indicated an extension not requested by the client), the client
// MUST _Fail the WebSocket Connection_.
// If the response includes a |Sec-WebSocket-Protocol| header field
// and this header field indicates the use of a subprotocol that was
// not present in the client's handshake (the server has indicated a
// subprotocol not requested by the client), the client MUST _Fail
// the WebSocket Connection_.
}
catch (Exception)
{
throw;
}
return(true);
}