| // Copyright (c) 2013, the Dart project authors. Please see the AUTHORS file |
| // for details. All rights reserved. Use of this source code is governed by a |
| // BSD-style license that can be found in the LICENSE file. |
| |
| part of dart.io; |
| |
| const String _webSocketGUID = "258EAFA5-E914-47DA-95CA-C5AB0DC85B11"; |
| |
| // Matches _WebSocketOpcode. |
| class _WebSocketMessageType { |
| static const int NONE = 0; |
| static const int TEXT = 1; |
| static const int BINARY = 2; |
| } |
| |
| |
| class _WebSocketOpcode { |
| static const int CONTINUATION = 0; |
| static const int TEXT = 1; |
| static const int BINARY = 2; |
| static const int RESERVED_3 = 3; |
| static const int RESERVED_4 = 4; |
| static const int RESERVED_5 = 5; |
| static const int RESERVED_6 = 6; |
| static const int RESERVED_7 = 7; |
| static const int CLOSE = 8; |
| static const int PING = 9; |
| static const int PONG = 10; |
| static const int RESERVED_B = 11; |
| static const int RESERVED_C = 12; |
| static const int RESERVED_D = 13; |
| static const int RESERVED_E = 14; |
| static const int RESERVED_F = 15; |
| } |
| |
| /** |
| * The web socket protocol transformer handles the protocol byte stream |
| * which is supplied through the [:handleData:]. As the protocol is processed, |
| * it'll output frame data as either a List<int> or String. |
| * |
| * Important infomation about usage: Be sure you use cancelOnError, so the |
| * socket will be closed when the processer encounter an error. Not using it |
| * will lead to undefined behaviour. |
| */ |
| // TODO(ajohnsen): make this transformer reusable? |
| class _WebSocketProtocolTransformer implements StreamTransformer, EventSink { |
| static const int START = 0; |
| static const int LEN_FIRST = 1; |
| static const int LEN_REST = 2; |
| static const int MASK = 3; |
| static const int PAYLOAD = 4; |
| static const int CLOSED = 5; |
| static const int FAILURE = 6; |
| |
| int _state = START; |
| bool _fin = false; |
| int _opcode = -1; |
| int _len = -1; |
| bool _masked = false; |
| int _remainingLenBytes = -1; |
| int _remainingMaskingKeyBytes = 4; |
| int _remainingPayloadBytes = -1; |
| int _unmaskingIndex = 0; |
| int _currentMessageType = _WebSocketMessageType.NONE; |
| int closeCode = WebSocketStatus.NO_STATUS_RECEIVED; |
| String closeReason = ""; |
| |
| EventSink _eventSink; |
| |
| final bool _serverSide; |
| final List _maskingBytes = new List(4); |
| final BytesBuilder _payload = new BytesBuilder(copy: false); |
| |
| _WebSocketProtocolTransformer([this._serverSide = false]); |
| |
| Stream bind(Stream stream) { |
| return new Stream.eventTransformed( |
| stream, |
| (EventSink eventSink) { |
| if (_eventSink != null) { |
| throw new StateError("WebSocket transformer already used."); |
| } |
| _eventSink = eventSink; |
| return this; |
| }); |
| } |
| |
| void addError(Object error, [StackTrace stackTrace]) => |
| _eventSink.addError(error, stackTrace); |
| |
| void close() => _eventSink.close(); |
| |
| /** |
| * Process data received from the underlying communication channel. |
| */ |
| void add(Uint8List buffer) { |
| int count = buffer.length; |
| int index = 0; |
| int lastIndex = count; |
| if (_state == CLOSED) { |
| throw new WebSocketException("Data on closed connection"); |
| } |
| if (_state == FAILURE) { |
| throw new WebSocketException("Data on failed connection"); |
| } |
| while ((index < lastIndex) && _state != CLOSED && _state != FAILURE) { |
| int byte = buffer[index]; |
| if (_state <= LEN_REST) { |
| if (_state == START) { |
| _fin = (byte & 0x80) != 0; |
| if ((byte & 0x70) != 0) { |
| // The RSV1, RSV2 bits RSV3 must be all zero. |
| throw new WebSocketException("Protocol error"); |
| } |
| _opcode = (byte & 0xF); |
| if (_opcode <= _WebSocketOpcode.BINARY) { |
| if (_opcode == _WebSocketOpcode.CONTINUATION) { |
| if (_currentMessageType == _WebSocketMessageType.NONE) { |
| throw new WebSocketException("Protocol error"); |
| } |
| } else { |
| assert(_opcode == _WebSocketOpcode.TEXT || |
| _opcode == _WebSocketOpcode.BINARY); |
| if (_currentMessageType != _WebSocketMessageType.NONE) { |
| throw new WebSocketException("Protocol error"); |
| } |
| _currentMessageType = _opcode; |
| } |
| } else if (_opcode >= _WebSocketOpcode.CLOSE && |
| _opcode <= _WebSocketOpcode.PONG) { |
| // Control frames cannot be fragmented. |
| if (!_fin) throw new WebSocketException("Protocol error"); |
| } else { |
| throw new WebSocketException("Protocol error"); |
| } |
| _state = LEN_FIRST; |
| } else if (_state == LEN_FIRST) { |
| _masked = (byte & 0x80) != 0; |
| _len = byte & 0x7F; |
| if (_isControlFrame() && _len > 125) { |
| throw new WebSocketException("Protocol error"); |
| } |
| if (_len == 126) { |
| _len = 0; |
| _remainingLenBytes = 2; |
| _state = LEN_REST; |
| } else if (_len == 127) { |
| _len = 0; |
| _remainingLenBytes = 8; |
| _state = LEN_REST; |
| } else { |
| assert(_len < 126); |
| _lengthDone(); |
| } |
| } else { |
| assert(_state == LEN_REST); |
| _len = _len << 8 | byte; |
| _remainingLenBytes--; |
| if (_remainingLenBytes == 0) { |
| _lengthDone(); |
| } |
| } |
| } else { |
| if (_state == MASK) { |
| _maskingBytes[4 - _remainingMaskingKeyBytes--] = byte; |
| if (_remainingMaskingKeyBytes == 0) { |
| _maskDone(); |
| } |
| } else { |
| assert(_state == PAYLOAD); |
| // The payload is not handled one byte at a time but in blocks. |
| int payloadLength = min(lastIndex - index, _remainingPayloadBytes); |
| _remainingPayloadBytes -= payloadLength; |
| // Unmask payload if masked. |
| if (_masked) { |
| _unmask(index, payloadLength, buffer); |
| } |
| // Control frame and data frame share _payloads. |
| _payload.add( |
| new Uint8List.view(buffer.buffer, index, payloadLength)); |
| index += payloadLength; |
| if (_isControlFrame()) { |
| if (_remainingPayloadBytes == 0) _controlFrameEnd(); |
| } else { |
| if (_currentMessageType != _WebSocketMessageType.TEXT && |
| _currentMessageType != _WebSocketMessageType.BINARY) { |
| throw new WebSocketException("Protocol error"); |
| } |
| if (_remainingPayloadBytes == 0) _messageFrameEnd(); |
| } |
| |
| // Hack - as we always do index++ below. |
| index--; |
| } |
| } |
| |
| // Move to the next byte. |
| index++; |
| } |
| } |
| |
| void _unmask(int index, int length, Uint8List buffer) { |
| const int BLOCK_SIZE = 16; |
| // Skip Int32x4-version if message is small. |
| if (length >= BLOCK_SIZE) { |
| // Start by aligning to 16 bytes. |
| final int startOffset = BLOCK_SIZE - (index & 15); |
| final int end = index + startOffset; |
| for (int i = index; i < end; i++) { |
| buffer[i] ^= _maskingBytes[_unmaskingIndex++ & 3]; |
| } |
| index += startOffset; |
| length -= startOffset; |
| final int blockCount = length ~/ BLOCK_SIZE; |
| if (blockCount > 0) { |
| // Create mask block. |
| int mask = 0; |
| for (int i = 3; i >= 0; i--) { |
| mask = (mask << 8) | _maskingBytes[(_unmaskingIndex + i) & 3]; |
| } |
| Int32x4 blockMask = new Int32x4(mask, mask, mask, mask); |
| Int32x4List blockBuffer = new Int32x4List.view( |
| buffer.buffer, index, blockCount); |
| for (int i = 0; i < blockBuffer.length; i++) { |
| blockBuffer[i] ^= blockMask; |
| } |
| final int bytes = blockCount * BLOCK_SIZE; |
| index += bytes; |
| length -= bytes; |
| } |
| } |
| // Handle end. |
| final int end = index + length; |
| for (int i = index; i < end; i++) { |
| buffer[i] ^= _maskingBytes[_unmaskingIndex++ & 3]; |
| } |
| } |
| |
| void _lengthDone() { |
| if (_masked) { |
| if (!_serverSide) { |
| throw new WebSocketException("Received masked frame from server"); |
| } |
| _state = MASK; |
| } else { |
| if (_serverSide) { |
| throw new WebSocketException("Received unmasked frame from client"); |
| } |
| _remainingPayloadBytes = _len; |
| _startPayload(); |
| } |
| } |
| |
| void _maskDone() { |
| _remainingPayloadBytes = _len; |
| _startPayload(); |
| } |
| |
| void _startPayload() { |
| // If there is no actual payload perform perform callbacks without |
| // going through the PAYLOAD state. |
| if (_remainingPayloadBytes == 0) { |
| if (_isControlFrame()) { |
| switch (_opcode) { |
| case _WebSocketOpcode.CLOSE: |
| _state = CLOSED; |
| _eventSink.close(); |
| break; |
| case _WebSocketOpcode.PING: |
| _eventSink.add(new _WebSocketPing()); |
| break; |
| case _WebSocketOpcode.PONG: |
| _eventSink.add(new _WebSocketPong()); |
| break; |
| } |
| _prepareForNextFrame(); |
| } else { |
| _messageFrameEnd(); |
| } |
| } else { |
| _state = PAYLOAD; |
| } |
| } |
| |
| void _messageFrameEnd() { |
| if (_fin) { |
| switch (_currentMessageType) { |
| case _WebSocketMessageType.TEXT: |
| _eventSink.add(UTF8.decode(_payload.takeBytes())); |
| break; |
| case _WebSocketMessageType.BINARY: |
| _eventSink.add(_payload.takeBytes()); |
| break; |
| } |
| _currentMessageType = _WebSocketMessageType.NONE; |
| } |
| _prepareForNextFrame(); |
| } |
| |
| void _controlFrameEnd() { |
| switch (_opcode) { |
| case _WebSocketOpcode.CLOSE: |
| closeCode = WebSocketStatus.NO_STATUS_RECEIVED; |
| var payload = _payload.takeBytes(); |
| if (payload.length > 0) { |
| if (payload.length == 1) { |
| throw new WebSocketException("Protocol error"); |
| } |
| closeCode = payload[0] << 8 | payload[1]; |
| if (closeCode == WebSocketStatus.NO_STATUS_RECEIVED) { |
| throw new WebSocketException("Protocol error"); |
| } |
| if (payload.length > 2) { |
| closeReason = UTF8.decode(payload.sublist(2)); |
| } |
| } |
| _state = CLOSED; |
| _eventSink.close(); |
| break; |
| |
| case _WebSocketOpcode.PING: |
| _eventSink.add(new _WebSocketPing(_payload.takeBytes())); |
| break; |
| |
| case _WebSocketOpcode.PONG: |
| _eventSink.add(new _WebSocketPong(_payload.takeBytes())); |
| break; |
| } |
| _prepareForNextFrame(); |
| } |
| |
| bool _isControlFrame() { |
| return _opcode == _WebSocketOpcode.CLOSE || |
| _opcode == _WebSocketOpcode.PING || |
| _opcode == _WebSocketOpcode.PONG; |
| } |
| |
| void _prepareForNextFrame() { |
| if (_state != CLOSED && _state != FAILURE) _state = START; |
| _fin = false; |
| _opcode = -1; |
| _len = -1; |
| _remainingLenBytes = -1; |
| _remainingMaskingKeyBytes = 4; |
| _remainingPayloadBytes = -1; |
| _unmaskingIndex = 0; |
| } |
| } |
| |
| |
| class _WebSocketPing { |
| final List<int> payload; |
| _WebSocketPing([this.payload = null]); |
| } |
| |
| |
| class _WebSocketPong { |
| final List<int> payload; |
| _WebSocketPong([this.payload = null]); |
| } |
| |
| |
| class _WebSocketTransformerImpl implements WebSocketTransformer { |
| final StreamController<WebSocket> _controller = |
| new StreamController<WebSocket>(sync: true); |
| final Function _protocolSelector; |
| |
| _WebSocketTransformerImpl(this._protocolSelector); |
| |
| Stream<WebSocket> bind(Stream<HttpRequest> stream) { |
| stream.listen((request) { |
| _upgrade(request, _protocolSelector) |
| .then((WebSocket webSocket) => _controller.add(webSocket)) |
| .catchError(_controller.addError); |
| }); |
| |
| return _controller.stream; |
| } |
| |
| static Future<WebSocket> _upgrade(HttpRequest request, _protocolSelector) { |
| var response = request.response; |
| if (!_isUpgradeRequest(request)) { |
| // Send error response. |
| response |
| ..statusCode = HttpStatus.BAD_REQUEST |
| ..close(); |
| return new Future.error( |
| new WebSocketException("Invalid WebSocket upgrade request")); |
| } |
| |
| Future upgrade(String protocol) { |
| // Send the upgrade response. |
| response |
| ..statusCode = HttpStatus.SWITCHING_PROTOCOLS |
| ..headers.add(HttpHeaders.CONNECTION, "Upgrade") |
| ..headers.add(HttpHeaders.UPGRADE, "websocket"); |
| String key = request.headers.value("Sec-WebSocket-Key"); |
| _SHA1 sha1 = new _SHA1(); |
| sha1.add("$key$_webSocketGUID".codeUnits); |
| String accept = _CryptoUtils.bytesToBase64(sha1.close()); |
| response.headers.add("Sec-WebSocket-Accept", accept); |
| if (protocol != null && protocol.isNotEmpty) { |
| response.headers.add("Sec-WebSocket-Protocol", protocol); |
| } |
| response.headers.contentLength = 0; |
| return response.detachSocket() |
| .then((socket) => new _WebSocketImpl._fromSocket( |
| socket, protocol, true)); |
| } |
| |
| var protocols = request.headers['Sec-WebSocket-Protocol']; |
| if (protocols != null && _protocolSelector != null) { |
| // The suggested protocols can be spread over multiple lines, each |
| // consisting of multiple protocols. To unify all of them, first join |
| // the lists with ', ' and then tokenize. |
| protocols = _HttpParser._tokenizeFieldValue(protocols.join(', ')); |
| return new Future(() => _protocolSelector(protocols)) |
| .then((protocol) { |
| if (protocols.indexOf(protocol) < 0) { |
| throw new WebSocketException( |
| "Selected protocol is not in the list of available protocols"); |
| } |
| return protocol; |
| }) |
| .catchError((error) { |
| response |
| ..statusCode = HttpStatus.INTERNAL_SERVER_ERROR |
| ..close(); |
| throw error; |
| }) |
| .then(upgrade); |
| } else { |
| return upgrade(null); |
| } |
| } |
| |
| static bool _isUpgradeRequest(HttpRequest request) { |
| if (request.method != "GET") { |
| return false; |
| } |
| if (request.headers[HttpHeaders.CONNECTION] == null) { |
| return false; |
| } |
| bool isUpgrade = false; |
| request.headers[HttpHeaders.CONNECTION].forEach((String value) { |
| if (value.toLowerCase() == "upgrade") isUpgrade = true; |
| }); |
| if (!isUpgrade) return false; |
| String upgrade = request.headers.value(HttpHeaders.UPGRADE); |
| if (upgrade == null || upgrade.toLowerCase() != "websocket") { |
| return false; |
| } |
| String version = request.headers.value("Sec-WebSocket-Version"); |
| if (version == null || version != "13") { |
| return false; |
| } |
| String key = request.headers.value("Sec-WebSocket-Key"); |
| if (key == null) { |
| return false; |
| } |
| return true; |
| } |
| } |
| |
| |
| // TODO(ajohnsen): Make this transformer reusable. |
| class _WebSocketOutgoingTransformer implements StreamTransformer, EventSink { |
| final _WebSocketImpl webSocket; |
| EventSink _eventSink; |
| |
| _WebSocketOutgoingTransformer(this.webSocket); |
| |
| Stream bind(Stream stream) { |
| return new Stream.eventTransformed( |
| stream, |
| (EventSink eventSink) { |
| if (_eventSink != null) { |
| throw new StateError("WebSocket transformer already used"); |
| } |
| _eventSink = eventSink; |
| return this; |
| }); |
| } |
| |
| void add(message) { |
| if (message is _WebSocketPong) { |
| addFrame(_WebSocketOpcode.PONG, message.payload); |
| return; |
| } |
| if (message is _WebSocketPing) { |
| addFrame(_WebSocketOpcode.PING, message.payload); |
| return; |
| } |
| List<int> data; |
| int opcode; |
| if (message != null) { |
| if (message is String) { |
| opcode = _WebSocketOpcode.TEXT; |
| data = UTF8.encode(message); |
| } else { |
| if (message is !List<int>) { |
| throw new ArgumentError(message); |
| } |
| opcode = _WebSocketOpcode.BINARY; |
| data = message; |
| } |
| } else { |
| opcode = _WebSocketOpcode.TEXT; |
| } |
| addFrame(opcode, data); |
| } |
| |
| void addError(Object error, [StackTrace stackTrace]) => |
| _eventSink.addError(error, stackTrace); |
| |
| void close() { |
| int code = webSocket._outCloseCode; |
| String reason = webSocket._outCloseReason; |
| List<int> data; |
| if (code != null) { |
| data = new List<int>(); |
| data.add((code >> 8) & 0xFF); |
| data.add(code & 0xFF); |
| if (reason != null) { |
| data.addAll(UTF8.encode(reason)); |
| } |
| } |
| addFrame(_WebSocketOpcode.CLOSE, data); |
| _eventSink.close(); |
| } |
| |
| void addFrame(int opcode, List<int> data) => |
| createFrame(opcode, data, webSocket._serverSide).forEach(_eventSink.add); |
| |
| static Iterable createFrame(int opcode, List<int> data, bool serverSide) { |
| bool mask = !serverSide; // Masking not implemented for server. |
| int dataLength = data == null ? 0 : data.length; |
| // Determine the header size. |
| int headerSize = (mask) ? 6 : 2; |
| if (dataLength > 65535) { |
| headerSize += 8; |
| } else if (dataLength > 125) { |
| headerSize += 2; |
| } |
| Uint8List header = new Uint8List(headerSize); |
| int index = 0; |
| // Set FIN and opcode. |
| header[index++] = 0x80 | opcode; |
| // Determine size and position of length field. |
| int lengthBytes = 1; |
| int firstLengthByte = 1; |
| if (dataLength > 65535) { |
| header[index++] = 127; |
| lengthBytes = 8; |
| } else if (dataLength > 125) { |
| header[index++] = 126; |
| lengthBytes = 2; |
| } |
| // Write the length in network byte order into the header. |
| for (int i = 0; i < lengthBytes; i++) { |
| header[index++] = dataLength >> (((lengthBytes - 1) - i) * 8) & 0xFF; |
| } |
| if (mask) { |
| header[1] |= 1 << 7; |
| var maskBytes = _IOCrypto.getRandomBytes(4); |
| header.setRange(index, index + 4, maskBytes); |
| index += 4; |
| if (data != null) { |
| Uint8List list; |
| // If this is a text message just do the masking inside the |
| // encoded data. |
| if (opcode == _WebSocketOpcode.TEXT && data is Uint8List) { |
| list = data; |
| } else { |
| if (data is Uint8List) { |
| list = new Uint8List.fromList(data); |
| } else { |
| list = new Uint8List(data.length); |
| for (int i = 0; i < data.length; i++) { |
| if (data[i] < 0 || 255 < data[i]) { |
| throw new ArgumentError( |
| "List element is not a byte value " |
| "(value ${data[i]} at index $i)"); |
| } |
| list[i] = data[i]; |
| } |
| } |
| } |
| const int BLOCK_SIZE = 16; |
| int blockCount = list.length ~/ BLOCK_SIZE; |
| if (blockCount > 0) { |
| // Create mask block. |
| int mask = 0; |
| for (int i = 3; i >= 0; i--) { |
| mask = (mask << 8) | maskBytes[i]; |
| } |
| Int32x4 blockMask = new Int32x4(mask, mask, mask, mask); |
| Int32x4List blockBuffer = new Int32x4List.view( |
| list.buffer, 0, blockCount); |
| for (int i = 0; i < blockBuffer.length; i++) { |
| blockBuffer[i] ^= blockMask; |
| } |
| } |
| // Handle end. |
| for (int i = blockCount * BLOCK_SIZE; i < list.length; i++) { |
| list[i] ^= maskBytes[i & 3]; |
| } |
| data = list; |
| } |
| } |
| assert(index == headerSize); |
| if (data == null) { |
| return [header]; |
| } else { |
| return [header, data]; |
| } |
| } |
| } |
| |
| |
| class _WebSocketConsumer implements StreamConsumer { |
| final _WebSocketImpl webSocket; |
| final Socket socket; |
| StreamController _controller; |
| StreamSubscription _subscription; |
| bool _issuedPause = false; |
| bool _closed = false; |
| Completer _closeCompleter = new Completer(); |
| Completer _completer; |
| |
| _WebSocketConsumer(this.webSocket, this.socket); |
| |
| void _onListen() { |
| if (_subscription != null) { |
| _subscription.cancel(); |
| } |
| } |
| |
| void _onPause() { |
| if (_subscription != null) { |
| _subscription.pause(); |
| } else { |
| _issuedPause = true; |
| } |
| } |
| |
| void _onResume() { |
| if (_subscription != null) { |
| _subscription.resume(); |
| } else { |
| _issuedPause = false; |
| } |
| } |
| |
| void _cancel() { |
| if (_subscription != null) { |
| var subscription = _subscription; |
| _subscription = null; |
| subscription.cancel(); |
| } |
| } |
| |
| _ensureController() { |
| if (_controller != null) return; |
| _controller = new StreamController(sync: true, |
| onPause: _onPause, |
| onResume: _onResume, |
| onCancel: _onListen); |
| var stream = _controller.stream.transform( |
| new _WebSocketOutgoingTransformer(webSocket)); |
| socket.addStream(stream) |
| .then((_) { |
| _done(); |
| _closeCompleter.complete(webSocket); |
| }, onError: (error, StackTrace stackTrace) { |
| _closed = true; |
| _cancel(); |
| if (error is ArgumentError) { |
| if (!_done(error, stackTrace)) { |
| _closeCompleter.completeError(error, stackTrace); |
| } |
| } else { |
| _done(); |
| _closeCompleter.complete(webSocket); |
| } |
| }); |
| } |
| |
| bool _done([error, StackTrace stackTrace]) { |
| if (_completer == null) return false; |
| if (error != null) { |
| _completer.completeError(error, stackTrace); |
| } else { |
| _completer.complete(webSocket); |
| } |
| _completer = null; |
| return true; |
| } |
| |
| Future addStream(var stream) { |
| if (_closed) { |
| stream.listen(null).cancel(); |
| return new Future.value(webSocket); |
| } |
| _ensureController(); |
| _completer = new Completer(); |
| _subscription = stream.listen( |
| (data) { |
| _controller.add(data); |
| }, |
| onDone: _done, |
| onError: _done, |
| cancelOnError: true); |
| if (_issuedPause) { |
| _subscription.pause(); |
| _issuedPause = false; |
| } |
| return _completer.future; |
| } |
| |
| Future close() { |
| _ensureController(); |
| Future closeSocket() { |
| return socket.close().catchError((_) {}).then((_) => webSocket); |
| } |
| _controller.close(); |
| return _closeCompleter.future.then((_) => closeSocket()); |
| } |
| |
| void add(data) { |
| if (_closed) return; |
| _ensureController(); |
| _controller.add(data); |
| } |
| |
| void closeSocket() { |
| _closed = true; |
| _cancel(); |
| close(); |
| } |
| } |
| |
| |
| class _WebSocketImpl extends Stream with _ServiceObject implements WebSocket { |
| // Use default Map so we keep order. |
| static Map<int, _WebSocketImpl> _webSockets = new Map<int, _WebSocketImpl>(); |
| |
| final String protocol; |
| |
| StreamController _controller; |
| StreamSubscription _subscription; |
| StreamSink _sink; |
| |
| final _socket; |
| final bool _serverSide; |
| int _readyState = WebSocket.CONNECTING; |
| bool _writeClosed = false; |
| int _closeCode; |
| String _closeReason; |
| Duration _pingInterval; |
| Timer _pingTimer; |
| _WebSocketConsumer _consumer; |
| |
| int _outCloseCode; |
| String _outCloseReason; |
| Timer _closeTimer; |
| |
| static final HttpClient _httpClient = new HttpClient(); |
| |
| static Future<WebSocket> connect(String url, List<String> protocols) { |
| Uri uri = Uri.parse(url); |
| if (uri.scheme != "ws" && uri.scheme != "wss") { |
| throw new WebSocketException("Unsupported URL scheme '${uri.scheme}'"); |
| } |
| if (uri.userInfo != "") { |
| throw new WebSocketException("Unsupported user info '${uri.userInfo}'"); |
| } |
| |
| Random random = new Random(); |
| // Generate 16 random bytes. |
| Uint8List nonceData = new Uint8List(16); |
| for (int i = 0; i < 16; i++) { |
| nonceData[i] = random.nextInt(256); |
| } |
| String nonce = _CryptoUtils.bytesToBase64(nonceData); |
| |
| uri = new Uri(scheme: uri.scheme == "wss" ? "https" : "http", |
| userInfo: uri.userInfo, |
| host: uri.host, |
| port: uri.port, |
| path: uri.path, |
| query: uri.query, |
| fragment: uri.fragment); |
| return _httpClient.openUrl("GET", uri) |
| .then((request) { |
| // Setup the initial handshake. |
| request.headers |
| ..add(HttpHeaders.CONNECTION, "Upgrade") |
| ..set(HttpHeaders.UPGRADE, "websocket") |
| ..set("Sec-WebSocket-Key", nonce) |
| ..set("Cache-Control", "no-cache") |
| ..set("Sec-WebSocket-Version", "13"); |
| if (protocols.isNotEmpty) { |
| request.headers.add("Sec-WebSocket-Protocol", protocols); |
| } |
| return request.close(); |
| }) |
| .then((response) { |
| void error(String message) { |
| // Flush data. |
| response.detachSocket().then((socket) { |
| socket.destroy(); |
| }); |
| throw new WebSocketException(message); |
| } |
| if (response.statusCode != HttpStatus.SWITCHING_PROTOCOLS || |
| response.headers[HttpHeaders.CONNECTION] == null || |
| !response.headers[HttpHeaders.CONNECTION].any( |
| (value) => value.toLowerCase() == "upgrade") || |
| response.headers.value(HttpHeaders.UPGRADE).toLowerCase() != |
| "websocket") { |
| error("Connection to '$uri' was not upgraded to websocket"); |
| } |
| String accept = response.headers.value("Sec-WebSocket-Accept"); |
| if (accept == null) { |
| error("Response did not contain a 'Sec-WebSocket-Accept' header"); |
| } |
| _SHA1 sha1 = new _SHA1(); |
| sha1.add("$nonce$_webSocketGUID".codeUnits); |
| List<int> expectedAccept = sha1.close(); |
| List<int> receivedAccept = _CryptoUtils.base64StringToBytes(accept); |
| if (expectedAccept.length != receivedAccept.length) { |
| error("Reasponse header 'Sec-WebSocket-Accept' is the wrong length"); |
| } |
| for (int i = 0; i < expectedAccept.length; i++) { |
| if (expectedAccept[i] != receivedAccept[i]) { |
| error("Bad response 'Sec-WebSocket-Accept' header"); |
| } |
| } |
| var protocol = response.headers.value('Sec-WebSocket-Protocol'); |
| return response.detachSocket() |
| .then((socket) => new _WebSocketImpl._fromSocket(socket, protocol)); |
| }); |
| } |
| |
| _WebSocketImpl._fromSocket(this._socket, this.protocol, |
| [this._serverSide = false]) { |
| _consumer = new _WebSocketConsumer(this, _socket); |
| _sink = new _StreamSinkImpl(_consumer); |
| _readyState = WebSocket.OPEN; |
| |
| var transformer = new _WebSocketProtocolTransformer(_serverSide); |
| _subscription = _socket.transform(transformer).listen( |
| (data) { |
| if (data is _WebSocketPing) { |
| if (!_writeClosed) _consumer.add(new _WebSocketPong(data.payload)); |
| } else if (data is _WebSocketPong) { |
| // Simply set pingInterval, as it'll cancel any timers. |
| pingInterval = _pingInterval; |
| } else { |
| _controller.add(data); |
| } |
| }, |
| onError: (error) { |
| if (_closeTimer != null) _closeTimer.cancel(); |
| if (error is FormatException) { |
| _close(WebSocketStatus.INVALID_FRAME_PAYLOAD_DATA); |
| } else { |
| _close(WebSocketStatus.PROTOCOL_ERROR); |
| } |
| // An error happened, set the close code set above. |
| _closeCode = _outCloseCode; |
| _closeReason = _outCloseReason; |
| _controller.close(); |
| }, |
| onDone: () { |
| if (_closeTimer != null) _closeTimer.cancel(); |
| if (_readyState == WebSocket.OPEN) { |
| _readyState = WebSocket.CLOSING; |
| if (!_isReservedStatusCode(transformer.closeCode)) { |
| _close(transformer.closeCode); |
| } else { |
| _close(); |
| } |
| _readyState = WebSocket.CLOSED; |
| } |
| // Protocol close, use close code from transformer. |
| _closeCode = transformer.closeCode; |
| _closeReason = transformer.closeReason; |
| _controller.close(); |
| }, |
| cancelOnError: true); |
| _subscription.pause(); |
| _controller = new StreamController(sync: true, |
| onListen: _subscription.resume, |
| onPause: _subscription.pause, |
| onResume: _subscription.resume); |
| |
| _webSockets[_serviceId] = this; |
| try { _socket._owner = this; } catch (_) {} |
| } |
| |
| StreamSubscription listen(void onData(message), |
| {Function onError, |
| void onDone(), |
| bool cancelOnError}) { |
| return _controller.stream.listen(onData, |
| onError: onError, |
| onDone: onDone, |
| cancelOnError: cancelOnError); |
| } |
| |
| Duration get pingInterval => _pingInterval; |
| |
| void set pingInterval(Duration interval) { |
| if (_writeClosed) return; |
| if (_pingTimer != null) _pingTimer.cancel(); |
| _pingInterval = interval; |
| |
| if (_pingInterval == null) return; |
| |
| _pingTimer = new Timer(_pingInterval, () { |
| if (_writeClosed) return; |
| _consumer.add(new _WebSocketPing()); |
| _pingTimer = new Timer(_pingInterval, () { |
| // No pong received. |
| _close(WebSocketStatus.GOING_AWAY); |
| }); |
| }); |
| } |
| |
| int get readyState => _readyState; |
| |
| String get extensions => null; |
| int get closeCode => _closeCode; |
| String get closeReason => _closeReason; |
| |
| void add(data) => _sink.add(data); |
| void addError(error, [StackTrace stackTrace]) => |
| _sink.addError(error, stackTrace); |
| Future addStream(Stream stream) => _sink.addStream(stream); |
| Future get done => _sink.done; |
| |
| Future close([int code, String reason]) { |
| if (_isReservedStatusCode(code)) { |
| throw new WebSocketException("Reserved status code $code"); |
| } |
| if (_outCloseCode == null) { |
| _outCloseCode = code; |
| _outCloseReason = reason; |
| } |
| if (_closeTimer == null && !_controller.isClosed) { |
| // When closing the web-socket, we no longer accept data. |
| _closeTimer = new Timer(const Duration(seconds: 5), () { |
| // Reuse code and reason from the local close. |
| _closeCode = _outCloseCode; |
| _closeReason = _outCloseReason; |
| _subscription.cancel(); |
| _controller.close(); |
| _webSockets.remove(_serviceId); |
| }); |
| } |
| return _sink.close(); |
| } |
| |
| void _close([int code, String reason]) { |
| if (_writeClosed) return; |
| if (_outCloseCode == null) { |
| _outCloseCode = code; |
| _outCloseReason = reason; |
| } |
| _writeClosed = true; |
| _consumer.closeSocket(); |
| _webSockets.remove(_serviceId); |
| } |
| |
| String get _serviceTypePath => 'io/websockets'; |
| String get _serviceTypeName => 'WebSocket'; |
| |
| Map _toJSON(bool ref) { |
| var name = '${_socket.address.host}:${_socket.port}'; |
| var r = { |
| 'id': _servicePath, |
| 'type': _serviceType(ref), |
| 'name': name, |
| 'user_name': name, |
| }; |
| if (ref) { |
| return r; |
| } |
| try { |
| r['socket'] = _socket._toJSON(true); |
| } catch (_) { |
| r['socket'] = { |
| 'id': _servicePath, |
| 'type': '@Socket', |
| 'name': 'UserSocket', |
| 'user_name': 'UserSocket', |
| }; |
| } |
| return r; |
| } |
| |
| static bool _isReservedStatusCode(int code) { |
| return code != null && |
| (code < WebSocketStatus.NORMAL_CLOSURE || |
| code == WebSocketStatus.RESERVED_1004 || |
| code == WebSocketStatus.NO_STATUS_RECEIVED || |
| code == WebSocketStatus.ABNORMAL_CLOSURE || |
| (code > WebSocketStatus.INTERNAL_SERVER_ERROR && |
| code < WebSocketStatus.RESERVED_1015) || |
| (code >= WebSocketStatus.RESERVED_1015 && |
| code < 3000)); |
| } |
| } |