| // 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._http; |
| |
| // Global constants. |
| class _Const { |
| // Bytes for "HTTP". |
| static const HTTP = [72, 84, 84, 80]; |
| // Bytes for "HTTP/1.". |
| static const HTTP1DOT = [72, 84, 84, 80, 47, 49, 46]; |
| // Bytes for "HTTP/1.0". |
| static const HTTP10 = [72, 84, 84, 80, 47, 49, 46, 48]; |
| // Bytes for "HTTP/1.1". |
| static const HTTP11 = [72, 84, 84, 80, 47, 49, 46, 49]; |
| |
| static const bool T = true; |
| static const bool F = false; |
| // Loopup-map for the following characters: '()<>@,;:\\"/[]?={} \t'. |
| static const SEPARATOR_MAP = [ |
| F, F, F, F, F, F, F, F, F, T, F, F, F, F, F, F, F, F, F, F, F, F, F, F, // |
| F, F, F, F, F, F, F, F, T, F, T, F, F, F, F, F, T, T, F, F, T, F, F, T, // |
| F, F, F, F, F, F, F, F, F, F, T, T, T, T, T, T, T, F, F, F, F, F, F, F, // |
| F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, T, T, T, F, F, // |
| F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, // |
| F, F, F, T, F, T, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, // |
| F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, // |
| F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, // |
| F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, // |
| F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, // |
| F, F, F, F, F, F, F, F, F, F, F, F, F, F, F, F |
| ]; |
| } |
| |
| // Frequently used character codes. |
| class _CharCode { |
| static const int HT = 9; |
| static const int LF = 10; |
| static const int CR = 13; |
| static const int SP = 32; |
| static const int COMMA = 44; |
| static const int SLASH = 47; |
| static const int ZERO = 48; |
| static const int ONE = 49; |
| static const int COLON = 58; |
| static const int SEMI_COLON = 59; |
| } |
| |
| // States of the HTTP parser state machine. |
| class _State { |
| static const int START = 0; |
| static const int METHOD_OR_RESPONSE_HTTP_VERSION = 1; |
| static const int RESPONSE_HTTP_VERSION = 2; |
| static const int REQUEST_LINE_METHOD = 3; |
| static const int REQUEST_LINE_URI = 4; |
| static const int REQUEST_LINE_HTTP_VERSION = 5; |
| static const int REQUEST_LINE_ENDING = 6; |
| static const int RESPONSE_LINE_STATUS_CODE = 7; |
| static const int RESPONSE_LINE_REASON_PHRASE = 8; |
| static const int RESPONSE_LINE_ENDING = 9; |
| static const int HEADER_START = 10; |
| static const int HEADER_FIELD = 11; |
| static const int HEADER_VALUE_START = 12; |
| static const int HEADER_VALUE = 13; |
| static const int HEADER_VALUE_FOLD_OR_END_CR = 14; |
| static const int HEADER_VALUE_FOLD_OR_END = 15; |
| static const int HEADER_ENDING = 16; |
| |
| static const int CHUNK_SIZE_STARTING_CR = 17; |
| static const int CHUNK_SIZE_STARTING = 18; |
| static const int CHUNK_SIZE = 19; |
| static const int CHUNK_SIZE_EXTENSION = 20; |
| static const int CHUNK_SIZE_ENDING = 21; |
| static const int CHUNKED_BODY_DONE_CR = 22; |
| static const int CHUNKED_BODY_DONE = 23; |
| static const int BODY = 24; |
| static const int CLOSED = 25; |
| static const int UPGRADED = 26; |
| static const int FAILURE = 27; |
| |
| static const int FIRST_BODY_STATE = CHUNK_SIZE_STARTING_CR; |
| } |
| |
| // HTTP version of the request or response being parsed. |
| class _HttpVersion { |
| static const int UNDETERMINED = 0; |
| static const int HTTP10 = 1; |
| static const int HTTP11 = 2; |
| } |
| |
| // States of the HTTP parser state machine. |
| class _MessageType { |
| static const int UNDETERMINED = 0; |
| static const int REQUEST = 1; |
| static const int RESPONSE = 0; |
| } |
| |
| /// The _HttpDetachedStreamSubscription takes a subscription and some extra data, |
| /// and makes it possible to "inject" the data in from of other data events |
| /// from the subscription. |
| /// |
| /// It does so by overriding pause/resume, so that once the |
| /// _HttpDetachedStreamSubscription is resumed, it'll deliver the data before |
| /// resuming the underlying subscription. |
| class _HttpDetachedStreamSubscription implements StreamSubscription<Uint8List> { |
| final StreamSubscription<Uint8List> _subscription; |
| Uint8List? _injectData; |
| void Function(Uint8List data)? _userOnData; |
| bool _isCanceled = false; |
| bool _scheduled = false; |
| int _pauseCount = 1; |
| |
| _HttpDetachedStreamSubscription( |
| this._subscription, this._injectData, this._userOnData); |
| |
| bool get isPaused => _subscription.isPaused; |
| |
| Future<T> asFuture<T>([T? futureValue]) => |
| _subscription.asFuture<T>(futureValue as T); |
| |
| Future cancel() { |
| _isCanceled = true; |
| _injectData = null; |
| return _subscription.cancel(); |
| } |
| |
| void onData(void Function(Uint8List data)? handleData) { |
| _userOnData = handleData; |
| _subscription.onData(handleData); |
| } |
| |
| void onDone(void Function()? handleDone) { |
| _subscription.onDone(handleDone); |
| } |
| |
| void onError(Function? handleError) { |
| _subscription.onError(handleError); |
| } |
| |
| void pause([Future? resumeSignal]) { |
| if (_injectData == null) { |
| _subscription.pause(resumeSignal); |
| } else { |
| _pauseCount++; |
| if (resumeSignal != null) { |
| resumeSignal.whenComplete(resume); |
| } |
| } |
| } |
| |
| void resume() { |
| if (_injectData == null) { |
| _subscription.resume(); |
| } else { |
| _pauseCount--; |
| _maybeScheduleData(); |
| } |
| } |
| |
| void _maybeScheduleData() { |
| if (_scheduled) return; |
| if (_pauseCount != 0) return; |
| _scheduled = true; |
| scheduleMicrotask(() { |
| _scheduled = false; |
| if (_pauseCount > 0 || _isCanceled) return; |
| var data = _injectData!; |
| _injectData = null; |
| // To ensure that 'subscription.isPaused' is false, we resume the |
| // subscription here. This is fine as potential events are delayed. |
| _subscription.resume(); |
| _userOnData?.call(data); |
| }); |
| } |
| } |
| |
| class _HttpDetachedIncoming extends Stream<Uint8List> { |
| final StreamSubscription<Uint8List>? subscription; |
| final Uint8List? bufferedData; |
| |
| _HttpDetachedIncoming(this.subscription, this.bufferedData); |
| |
| StreamSubscription<Uint8List> listen(void Function(Uint8List event)? onData, |
| {Function? onError, void Function()? onDone, bool? cancelOnError}) { |
| var subscription = this.subscription; |
| if (subscription != null) { |
| subscription |
| ..onData(onData) |
| ..onError(onError) |
| ..onDone(onDone); |
| if (bufferedData == null) { |
| return subscription..resume(); |
| } |
| return _HttpDetachedStreamSubscription(subscription, bufferedData, onData) |
| ..resume(); |
| } else { |
| // TODO(26379): add test for this branch. |
| return Stream<Uint8List>.fromIterable([bufferedData!]).listen(onData, |
| onError: onError, onDone: onDone, cancelOnError: cancelOnError); |
| } |
| } |
| } |
| |
| /// HTTP parser which parses the data stream given to [consume]. |
| /// |
| /// If an HTTP parser error occurs, the parser will signal an error to either |
| /// the current _HttpIncoming or the _parser itself. |
| /// |
| /// The connection upgrades (e.g. switching from HTTP/1.1 to the |
| /// WebSocket protocol) is handled in a special way. If connection |
| /// upgrade is specified in the headers, then on the callback to |
| /// [:responseStart:] the [:upgrade:] property on the [:HttpParser:] |
| /// object will be [:true:] indicating that from now on the protocol is |
| /// not HTTP anymore and no more callbacks will happen, that is |
| /// [:dataReceived:] and [:dataEnd:] are not called in this case as |
| /// there is no more HTTP data. After the upgrade the method |
| /// [:readUnparsedData:] can be used to read any remaining bytes in the |
| /// HTTP parser which are part of the protocol the connection is |
| /// upgrading to. These bytes cannot be processed by the HTTP parser |
| /// and should be handled according to whatever protocol is being |
| /// upgraded to. |
| class _HttpParser extends Stream<_HttpIncoming> { |
| // State. |
| bool _parserCalled = false; |
| |
| // The data that is currently being parsed. |
| Uint8List? _buffer; |
| int _index = -1; |
| |
| // Whether a HTTP request is being parsed (as opposed to a response). |
| final bool _requestParser; |
| int _state = _State.START; |
| int? _httpVersionIndex; |
| int _messageType = _MessageType.UNDETERMINED; |
| int _statusCode = 0; |
| int _statusCodeLength = 0; |
| final List<int> _method = []; |
| final List<int> _uriOrReasonPhrase = []; |
| final List<int> _headerField = []; |
| final List<int> _headerValue = []; |
| static const _headerTotalSizeLimit = 1024 * 1024; |
| int _headersReceivedSize = 0; |
| |
| int _httpVersion = _HttpVersion.UNDETERMINED; |
| int _transferLength = -1; |
| bool _persistentConnection = false; |
| bool _connectionUpgrade = false; |
| bool _chunked = false; |
| |
| bool _noMessageBody = false; |
| int _remainingContent = -1; |
| bool _contentLength = false; |
| bool _transferEncoding = false; |
| bool connectMethod = false; |
| |
| _HttpHeaders? _headers; |
| |
| // The limit for parsing chunk size |
| static const _chunkSizeLimit = 0x7FFFFFFF; |
| |
| // The current incoming connection. |
| _HttpIncoming? _incoming; |
| StreamSubscription<Uint8List>? _socketSubscription; |
| bool _paused = true; |
| bool _bodyPaused = false; |
| final StreamController<_HttpIncoming> _controller; |
| StreamController<Uint8List>? _bodyController; |
| |
| factory _HttpParser.requestParser() { |
| return _HttpParser._(true); |
| } |
| |
| factory _HttpParser.responseParser() { |
| return _HttpParser._(false); |
| } |
| |
| _HttpParser._(this._requestParser) |
| : _controller = StreamController<_HttpIncoming>(sync: true) { |
| _controller |
| ..onListen = () { |
| _paused = false; |
| } |
| ..onPause = () { |
| _paused = true; |
| _pauseStateChanged(); |
| } |
| ..onResume = () { |
| _paused = false; |
| _pauseStateChanged(); |
| } |
| ..onCancel = () { |
| _socketSubscription?.cancel(); |
| }; |
| _reset(); |
| } |
| |
| StreamSubscription<_HttpIncoming> listen( |
| void Function(_HttpIncoming event)? onData, |
| {Function? onError, |
| void Function()? onDone, |
| bool? cancelOnError}) { |
| return _controller.stream.listen(onData, |
| onError: onError, onDone: onDone, cancelOnError: cancelOnError); |
| } |
| |
| void listenToStream(Stream<Uint8List> stream) { |
| // Listen to the stream and handle data accordingly. When a |
| // _HttpIncoming is created, _dataPause, _dataResume, _dataDone is |
| // given to provide a way of controlling the parser. |
| // TODO(ajohnsen): Remove _dataPause, _dataResume and _dataDone and clean up |
| // how the _HttpIncoming signals the parser. |
| _socketSubscription = |
| stream.listen(_onData, onError: _controller.addError, onDone: _onDone); |
| } |
| |
| void _parse() { |
| try { |
| _doParse(); |
| } catch (e, s) { |
| if (_state >= _State.CHUNK_SIZE_STARTING_CR && _state <= _State.BODY) { |
| _state = _State.FAILURE; |
| _reportBodyError(e, s); |
| } else { |
| _state = _State.FAILURE; |
| _reportHttpError(e, s); |
| } |
| } |
| } |
| |
| // Process end of headers. Returns true if the parser should stop |
| // parsing and return. This will be in case of either an upgrade |
| // request or a request or response with an empty body. |
| bool _headersEnd() { |
| var headers = _headers!; |
| // If method is CONNECT, response parser should ignore any Content-Length or |
| // Transfer-Encoding header fields in a successful response. |
| // [RFC 7231](https://tools.ietf.org/html/rfc7231#section-4.3.6) |
| if (!_requestParser && |
| _statusCode >= 200 && |
| _statusCode < 300 && |
| connectMethod) { |
| _transferLength = -1; |
| headers.chunkedTransferEncoding = false; |
| _chunked = false; |
| headers.removeAll(HttpHeaders.contentLengthHeader); |
| headers.removeAll(HttpHeaders.transferEncodingHeader); |
| } |
| headers._mutable = false; |
| |
| _transferLength = headers.contentLength; |
| // Ignore the Content-Length header if Transfer-Encoding |
| // is chunked (RFC 2616 section 4.4) |
| if (_chunked) _transferLength = -1; |
| |
| // If a request message has neither Content-Length nor |
| // Transfer-Encoding the message must not have a body (RFC |
| // 2616 section 4.3). |
| if (_messageType == _MessageType.REQUEST && |
| _transferLength < 0 && |
| _chunked == false) { |
| _transferLength = 0; |
| } |
| if (_connectionUpgrade) { |
| _state = _State.UPGRADED; |
| _transferLength = 0; |
| } |
| var incoming = _createIncoming(_transferLength); |
| if (_requestParser) { |
| incoming.method = String.fromCharCodes(_method); |
| incoming.uri = Uri.parse(String.fromCharCodes(_uriOrReasonPhrase)); |
| } else { |
| incoming.statusCode = _statusCode; |
| incoming.reasonPhrase = String.fromCharCodes(_uriOrReasonPhrase); |
| } |
| _method.clear(); |
| _uriOrReasonPhrase.clear(); |
| if (_connectionUpgrade) { |
| incoming.upgraded = true; |
| _parserCalled = false; |
| _closeIncoming(); |
| _controller.add(incoming); |
| return true; |
| } |
| if (_transferLength == 0 || |
| (_messageType == _MessageType.RESPONSE && _noMessageBody)) { |
| _reset(); |
| _closeIncoming(); |
| _controller.add(incoming); |
| return false; |
| } else if (_chunked) { |
| _state = _State.CHUNK_SIZE; |
| _remainingContent = 0; |
| } else if (_transferLength > 0) { |
| _remainingContent = _transferLength; |
| _state = _State.BODY; |
| } else { |
| // Neither chunked nor content length. End of body |
| // indicated by close. |
| _state = _State.BODY; |
| } |
| _parserCalled = false; |
| _controller.add(incoming); |
| return true; |
| } |
| |
| // From RFC 2616. |
| // generic-message = start-line |
| // *(message-header CRLF) |
| // CRLF |
| // [ message-body ] |
| // start-line = Request-Line | Status-Line |
| // Request-Line = Method SP Request-URI SP HTTP-Version CRLF |
| // Status-Line = HTTP-Version SP Status-Code SP Reason-Phrase CRLF |
| // message-header = field-name ":" [ field-value ] |
| // |
| // Per section 19.3 "Tolerant Applications" CRLF treats LF as a terminator |
| // and leading CR is ignored. Use of standalone CR is not allowed. |
| |
| void _doParse() { |
| assert(!_parserCalled); |
| _parserCalled = true; |
| if (_state == _State.CLOSED) { |
| throw HttpException("Data on closed connection"); |
| } |
| if (_state == _State.FAILURE) { |
| throw HttpException("Data on failed connection"); |
| } |
| while (_buffer != null && |
| _index < _buffer!.length && |
| _state != _State.FAILURE && |
| _state != _State.UPGRADED) { |
| // Depending on _incoming, we either break on _bodyPaused or _paused. |
| if ((_incoming != null && _bodyPaused) || |
| (_incoming == null && _paused)) { |
| _parserCalled = false; |
| return; |
| } |
| int index = _index; |
| int byte = _buffer![index]; |
| _index = index + 1; |
| switch (_state) { |
| case _State.START: |
| if (byte == _Const.HTTP[0]) { |
| // Start parsing method or HTTP version. |
| _httpVersionIndex = 1; |
| _state = _State.METHOD_OR_RESPONSE_HTTP_VERSION; |
| } else { |
| // Start parsing method. |
| if (!_isTokenChar(byte)) { |
| throw HttpException("Invalid request method"); |
| } |
| _addWithValidation(_method, byte); |
| if (!_requestParser) { |
| throw HttpException("Invalid response line"); |
| } |
| _state = _State.REQUEST_LINE_METHOD; |
| } |
| break; |
| |
| case _State.METHOD_OR_RESPONSE_HTTP_VERSION: |
| var httpVersionIndex = _httpVersionIndex!; |
| if (httpVersionIndex < _Const.HTTP.length && |
| byte == _Const.HTTP[httpVersionIndex]) { |
| // Continue parsing HTTP version. |
| _httpVersionIndex = httpVersionIndex + 1; |
| } else if (httpVersionIndex == _Const.HTTP.length && |
| byte == _CharCode.SLASH) { |
| // HTTP/ parsed. As method is a token this cannot be a |
| // method anymore. |
| _httpVersionIndex = httpVersionIndex + 1; |
| if (_requestParser) { |
| throw HttpException("Invalid request line"); |
| } |
| _state = _State.RESPONSE_HTTP_VERSION; |
| } else { |
| // Did not parse HTTP version. Expect method instead. |
| for (int i = 0; i < httpVersionIndex; i++) { |
| _addWithValidation(_method, _Const.HTTP[i]); |
| } |
| if (byte == _CharCode.SP) { |
| _state = _State.REQUEST_LINE_URI; |
| } else { |
| _addWithValidation(_method, byte); |
| _httpVersion = _HttpVersion.UNDETERMINED; |
| if (!_requestParser) { |
| throw HttpException("Invalid response line"); |
| } |
| _state = _State.REQUEST_LINE_METHOD; |
| } |
| } |
| break; |
| |
| case _State.RESPONSE_HTTP_VERSION: |
| var httpVersionIndex = _httpVersionIndex!; |
| if (httpVersionIndex < _Const.HTTP1DOT.length) { |
| // Continue parsing HTTP version. |
| _expect(byte, _Const.HTTP1DOT[httpVersionIndex]); |
| _httpVersionIndex = httpVersionIndex + 1; |
| } else if (httpVersionIndex == _Const.HTTP1DOT.length && |
| byte == _CharCode.ONE) { |
| // HTTP/1.1 parsed. |
| _httpVersion = _HttpVersion.HTTP11; |
| _persistentConnection = true; |
| _httpVersionIndex = httpVersionIndex + 1; |
| } else if (httpVersionIndex == _Const.HTTP1DOT.length && |
| byte == _CharCode.ZERO) { |
| // HTTP/1.0 parsed. |
| _httpVersion = _HttpVersion.HTTP10; |
| _persistentConnection = false; |
| _httpVersionIndex = httpVersionIndex + 1; |
| } else if (httpVersionIndex == _Const.HTTP1DOT.length + 1) { |
| _expect(byte, _CharCode.SP); |
| // HTTP version parsed. |
| _state = _State.RESPONSE_LINE_STATUS_CODE; |
| } else { |
| throw HttpException( |
| "Invalid response line, failed to parse HTTP version"); |
| } |
| break; |
| |
| case _State.REQUEST_LINE_METHOD: |
| if (byte == _CharCode.SP) { |
| _state = _State.REQUEST_LINE_URI; |
| } else { |
| if (_Const.SEPARATOR_MAP[byte] || |
| byte == _CharCode.CR || |
| byte == _CharCode.LF) { |
| throw HttpException("Invalid request method"); |
| } |
| _addWithValidation(_method, byte); |
| } |
| break; |
| |
| case _State.REQUEST_LINE_URI: |
| if (byte == _CharCode.SP) { |
| if (_uriOrReasonPhrase.isEmpty) { |
| throw HttpException("Invalid request, empty URI"); |
| } |
| _state = _State.REQUEST_LINE_HTTP_VERSION; |
| _httpVersionIndex = 0; |
| } else { |
| if (byte == _CharCode.CR || byte == _CharCode.LF) { |
| throw HttpException("Invalid request, unexpected $byte in URI"); |
| } |
| _addWithValidation(_uriOrReasonPhrase, byte); |
| } |
| break; |
| |
| case _State.REQUEST_LINE_HTTP_VERSION: |
| var httpVersionIndex = _httpVersionIndex!; |
| if (httpVersionIndex < _Const.HTTP1DOT.length) { |
| _expect(byte, _Const.HTTP11[httpVersionIndex]); |
| _httpVersionIndex = httpVersionIndex + 1; |
| } else if (_httpVersionIndex == _Const.HTTP1DOT.length) { |
| if (byte == _CharCode.ONE) { |
| // HTTP/1.1 parsed. |
| _httpVersion = _HttpVersion.HTTP11; |
| _persistentConnection = true; |
| _httpVersionIndex = httpVersionIndex + 1; |
| } else if (byte == _CharCode.ZERO) { |
| // HTTP/1.0 parsed. |
| _httpVersion = _HttpVersion.HTTP10; |
| _persistentConnection = false; |
| _httpVersionIndex = httpVersionIndex + 1; |
| } else { |
| throw HttpException("Invalid response, invalid HTTP version"); |
| } |
| } else { |
| if (byte == _CharCode.CR) { |
| _state = _State.REQUEST_LINE_ENDING; |
| } else if (byte == _CharCode.LF) { |
| _state = _State.REQUEST_LINE_ENDING; |
| _index = _index - 1; // Make the new state see the LF again. |
| } |
| } |
| break; |
| |
| case _State.REQUEST_LINE_ENDING: |
| _expect(byte, _CharCode.LF); |
| _messageType = _MessageType.REQUEST; |
| _state = _State.HEADER_START; |
| break; |
| |
| case _State.RESPONSE_LINE_STATUS_CODE: |
| if (byte == _CharCode.SP) { |
| _state = _State.RESPONSE_LINE_REASON_PHRASE; |
| } else if (byte == _CharCode.CR) { |
| // Some HTTP servers do not follow the spec and send |
| // \r?\n right after the status code. |
| _state = _State.RESPONSE_LINE_ENDING; |
| } else if (byte == _CharCode.LF) { |
| _state = _State.RESPONSE_LINE_ENDING; |
| _index = _index - 1; // Make the new state see the LF again. |
| } else { |
| _statusCodeLength++; |
| if (byte < 0x30 || byte > 0x39) { |
| throw HttpException("Invalid response status code with $byte"); |
| } else if (_statusCodeLength > 3) { |
| throw HttpException( |
| "Invalid response, status code is over 3 digits"); |
| } else { |
| _statusCode = _statusCode * 10 + byte - 0x30; |
| } |
| } |
| break; |
| |
| case _State.RESPONSE_LINE_REASON_PHRASE: |
| if (byte == _CharCode.CR) { |
| _state = _State.RESPONSE_LINE_ENDING; |
| } else if (byte == _CharCode.LF) { |
| _state = _State.RESPONSE_LINE_ENDING; |
| _index = _index - 1; // Make the new state see the LF again. |
| } else { |
| _addWithValidation(_uriOrReasonPhrase, byte); |
| } |
| break; |
| |
| case _State.RESPONSE_LINE_ENDING: |
| _expect(byte, _CharCode.LF); |
| _messageType == _MessageType.RESPONSE; |
| // Check whether this response will never have a body. |
| if (_statusCode <= 199 || _statusCode == 204 || _statusCode == 304) { |
| _noMessageBody = true; |
| } |
| _state = _State.HEADER_START; |
| break; |
| |
| case _State.HEADER_START: |
| _headers = _HttpHeaders(version!); |
| if (byte == _CharCode.CR) { |
| _state = _State.HEADER_ENDING; |
| } else if (byte == _CharCode.LF) { |
| _state = _State.HEADER_ENDING; |
| _index = _index - 1; // Make the new state see the LF again. |
| } else { |
| // Start of new header field. |
| _addWithValidation(_headerField, _toLowerCaseByte(byte)); |
| _state = _State.HEADER_FIELD; |
| } |
| break; |
| |
| case _State.HEADER_FIELD: |
| if (byte == _CharCode.COLON) { |
| _state = _State.HEADER_VALUE_START; |
| } else { |
| if (!_isTokenChar(byte)) { |
| throw HttpException("Invalid header field name, with $byte"); |
| } |
| _addWithValidation(_headerField, _toLowerCaseByte(byte)); |
| } |
| break; |
| |
| case _State.HEADER_VALUE_START: |
| if (byte == _CharCode.CR) { |
| _state = _State.HEADER_VALUE_FOLD_OR_END_CR; |
| } else if (byte == _CharCode.LF) { |
| _state = _State.HEADER_VALUE_FOLD_OR_END; |
| } else if (byte != _CharCode.SP && byte != _CharCode.HT) { |
| // Start of new header value. |
| _addWithValidation(_headerValue, byte); |
| _state = _State.HEADER_VALUE; |
| } |
| break; |
| |
| case _State.HEADER_VALUE: |
| if (byte == _CharCode.CR) { |
| _state = _State.HEADER_VALUE_FOLD_OR_END_CR; |
| } else if (byte == _CharCode.LF) { |
| _state = _State.HEADER_VALUE_FOLD_OR_END; |
| } else { |
| _addWithValidation(_headerValue, byte); |
| } |
| break; |
| |
| case _State.HEADER_VALUE_FOLD_OR_END_CR: |
| _expect(byte, _CharCode.LF); |
| _state = _State.HEADER_VALUE_FOLD_OR_END; |
| break; |
| |
| case _State.HEADER_VALUE_FOLD_OR_END: |
| if (byte == _CharCode.SP || byte == _CharCode.HT) { |
| _state = _State.HEADER_VALUE_START; |
| } else { |
| String headerField = String.fromCharCodes(_headerField); |
| String headerValue = String.fromCharCodes(_headerValue); |
| const errorIfBothText = "Both Content-Length and Transfer-Encoding " |
| "are specified, at most one is allowed"; |
| if (headerField == HttpHeaders.contentLengthHeader) { |
| // Content Length header should not have more than one occurrence |
| // or coexist with Transfer Encoding header. |
| if (_contentLength) { |
| throw HttpException("The Content-Length header occurred " |
| "more than once, at most one is allowed."); |
| } else if (_transferEncoding) { |
| throw HttpException(errorIfBothText); |
| } |
| _contentLength = true; |
| } else if (headerField == HttpHeaders.transferEncodingHeader) { |
| _transferEncoding = true; |
| if (_caseInsensitiveCompare("chunked".codeUnits, _headerValue)) { |
| _chunked = true; |
| } |
| if (_contentLength) { |
| throw HttpException(errorIfBothText); |
| } |
| } |
| var headers = _headers!; |
| if (headerField == HttpHeaders.connectionHeader) { |
| List<String> tokens = _tokenizeFieldValue(headerValue); |
| final bool isResponse = _messageType == _MessageType.RESPONSE; |
| final bool isUpgradeCode = |
| (_statusCode == HttpStatus.upgradeRequired) || |
| (_statusCode == HttpStatus.switchingProtocols); |
| for (int i = 0; i < tokens.length; i++) { |
| final bool isUpgrade = _caseInsensitiveCompare( |
| "upgrade".codeUnits, tokens[i].codeUnits); |
| if ((isUpgrade && !isResponse) || |
| (isUpgrade && isResponse && isUpgradeCode)) { |
| _connectionUpgrade = true; |
| } |
| headers._add(headerField, tokens[i]); |
| } |
| } else { |
| headers._add(headerField, headerValue); |
| } |
| _headerField.clear(); |
| _headerValue.clear(); |
| |
| if (byte == _CharCode.CR) { |
| _state = _State.HEADER_ENDING; |
| } else if (byte == _CharCode.LF) { |
| _state = _State.HEADER_ENDING; |
| _index = _index - 1; // Make the new state see the LF again. |
| } else { |
| // Start of new header field. |
| _state = _State.HEADER_FIELD; |
| _addWithValidation(_headerField, _toLowerCaseByte(byte)); |
| } |
| } |
| break; |
| |
| case _State.HEADER_ENDING: |
| _expect(byte, _CharCode.LF); |
| if (_headersEnd()) { |
| return; |
| } |
| break; |
| |
| case _State.CHUNK_SIZE_STARTING_CR: |
| if (byte == _CharCode.LF) { |
| _state = _State.CHUNK_SIZE_STARTING; |
| _index = _index - 1; // Make the new state see the LF again. |
| break; |
| } |
| _expect(byte, _CharCode.CR); |
| _state = _State.CHUNK_SIZE_STARTING; |
| break; |
| |
| case _State.CHUNK_SIZE_STARTING: |
| _expect(byte, _CharCode.LF); |
| _state = _State.CHUNK_SIZE; |
| break; |
| |
| case _State.CHUNK_SIZE: |
| if (byte == _CharCode.CR) { |
| _state = _State.CHUNK_SIZE_ENDING; |
| } else if (byte == _CharCode.LF) { |
| _state = _State.CHUNK_SIZE_ENDING; |
| _index = _index - 1; // Make the new state see the LF again. |
| } else if (byte == _CharCode.SEMI_COLON) { |
| _state = _State.CHUNK_SIZE_EXTENSION; |
| } else { |
| int value = _expectHexDigit(byte); |
| // Checks whether (_remainingContent * 16 + value) overflows. |
| if (_remainingContent > _chunkSizeLimit >> 4) { |
| throw HttpException('Chunk size overflows the integer'); |
| } |
| _remainingContent = _remainingContent * 16 + value; |
| } |
| break; |
| |
| case _State.CHUNK_SIZE_EXTENSION: |
| if (byte == _CharCode.CR) { |
| _state = _State.CHUNK_SIZE_ENDING; |
| } else if (byte == _CharCode.LF) { |
| _state = _State.CHUNK_SIZE_ENDING; |
| _index = _index - 1; // Make the new state see the LF again. |
| } |
| break; |
| |
| case _State.CHUNK_SIZE_ENDING: |
| _expect(byte, _CharCode.LF); |
| if (_remainingContent > 0) { |
| _state = _State.BODY; |
| } else { |
| _state = _State.CHUNKED_BODY_DONE_CR; |
| } |
| break; |
| |
| case _State.CHUNKED_BODY_DONE_CR: |
| if (byte == _CharCode.LF) { |
| _state = _State.CHUNKED_BODY_DONE; |
| _index = _index - 1; // Make the new state see the LF again. |
| break; |
| } |
| _expect(byte, _CharCode.CR); |
| break; |
| |
| case _State.CHUNKED_BODY_DONE: |
| _expect(byte, _CharCode.LF); |
| _reset(); |
| _closeIncoming(); |
| break; |
| |
| case _State.BODY: |
| // The body is not handled one byte at a time but in blocks. |
| _index = _index - 1; |
| var buffer = _buffer!; |
| int dataAvailable = buffer.length - _index; |
| if (_remainingContent >= 0 && dataAvailable > _remainingContent) { |
| dataAvailable = _remainingContent; |
| } |
| // Always present the data as a view. This way we can handle all |
| // cases like this, and the user will not experience different data |
| // typed (which could lead to polymorphic user code). |
| Uint8List data = Uint8List.view( |
| buffer.buffer, buffer.offsetInBytes + _index, dataAvailable); |
| _bodyController!.add(data); |
| if (_remainingContent != -1) { |
| _remainingContent -= data.length; |
| } |
| _index = _index + data.length; |
| if (_remainingContent == 0) { |
| if (!_chunked) { |
| _reset(); |
| _closeIncoming(); |
| } else { |
| _state = _State.CHUNK_SIZE_STARTING_CR; |
| } |
| } |
| break; |
| |
| case _State.FAILURE: |
| // Should be unreachable. |
| assert(false); |
| break; |
| |
| default: |
| // Should be unreachable. |
| assert(false); |
| break; |
| } |
| } |
| |
| _parserCalled = false; |
| var buffer = _buffer; |
| if (buffer != null && _index == buffer.length) { |
| // If all data is parsed release the buffer and resume receiving |
| // data. |
| _releaseBuffer(); |
| if (_state != _State.UPGRADED && _state != _State.FAILURE) { |
| _socketSubscription!.resume(); |
| } |
| } |
| } |
| |
| void _onData(Uint8List buffer) { |
| _socketSubscription!.pause(); |
| assert(_buffer == null); |
| _buffer = buffer; |
| _index = 0; |
| _parse(); |
| } |
| |
| void _onDone() { |
| // onDone cancels the subscription. |
| _socketSubscription = null; |
| if (_state == _State.CLOSED || _state == _State.FAILURE) return; |
| |
| if (_incoming != null) { |
| if (_state != _State.UPGRADED && |
| !(_state == _State.START && !_requestParser) && |
| !(_state == _State.BODY && !_chunked && _transferLength == -1)) { |
| _reportBodyError( |
| HttpException("Connection closed while receiving data")); |
| } |
| _closeIncoming(true); |
| _controller.close(); |
| return; |
| } |
| // If the connection is idle the HTTP stream is closed. |
| if (_state == _State.START) { |
| if (!_requestParser) { |
| _reportHttpError( |
| HttpException("Connection closed before full header was received")); |
| } |
| _controller.close(); |
| return; |
| } |
| |
| if (_state == _State.UPGRADED) { |
| _controller.close(); |
| return; |
| } |
| |
| if (_state < _State.FIRST_BODY_STATE) { |
| _state = _State.FAILURE; |
| // Report the error through the error callback if any. Otherwise |
| // throw the error. |
| _reportHttpError( |
| HttpException("Connection closed before full header was received")); |
| _controller.close(); |
| return; |
| } |
| |
| if (!_chunked && _transferLength == -1) { |
| _state = _State.CLOSED; |
| } else { |
| _state = _State.FAILURE; |
| // Report the error through the error callback if any. Otherwise |
| // throw the error. |
| _reportHttpError( |
| HttpException("Connection closed before full body was received")); |
| } |
| _controller.close(); |
| } |
| |
| String? get version { |
| switch (_httpVersion) { |
| case _HttpVersion.HTTP10: |
| return "1.0"; |
| case _HttpVersion.HTTP11: |
| return "1.1"; |
| } |
| return null; |
| } |
| |
| int get messageType => _messageType; |
| int get transferLength => _transferLength; |
| bool get upgrade => _connectionUpgrade && _state == _State.UPGRADED; |
| bool get persistentConnection => _persistentConnection; |
| |
| void set isHead(bool value) { |
| _noMessageBody = valueOfNonNullableParamWithDefault<bool>(value, false); |
| } |
| |
| _HttpDetachedIncoming detachIncoming() { |
| // Simulate detached by marking as upgraded. |
| _state = _State.UPGRADED; |
| return _HttpDetachedIncoming(_socketSubscription, readUnparsedData()); |
| } |
| |
| Uint8List? readUnparsedData() { |
| var buffer = _buffer; |
| if (buffer == null) return null; |
| var index = _index; |
| if (index == buffer.length) return null; |
| var result = buffer.sublist(index); |
| _releaseBuffer(); |
| return result; |
| } |
| |
| void _reset() { |
| if (_state == _State.UPGRADED) return; |
| _state = _State.START; |
| _messageType = _MessageType.UNDETERMINED; |
| _headerField.clear(); |
| _headerValue.clear(); |
| _headersReceivedSize = 0; |
| _method.clear(); |
| _uriOrReasonPhrase.clear(); |
| |
| _statusCode = 0; |
| _statusCodeLength = 0; |
| |
| _httpVersion = _HttpVersion.UNDETERMINED; |
| _transferLength = -1; |
| _persistentConnection = false; |
| _connectionUpgrade = false; |
| _chunked = false; |
| |
| _noMessageBody = false; |
| _remainingContent = -1; |
| |
| _contentLength = false; |
| _transferEncoding = false; |
| |
| _headers = null; |
| } |
| |
| void _releaseBuffer() { |
| _buffer = null; |
| _index = -1; |
| } |
| |
| static bool _isTokenChar(int byte) { |
| return byte > 31 && byte < 128 && !_Const.SEPARATOR_MAP[byte]; |
| } |
| |
| static bool _isValueChar(int byte) { |
| return (byte > 31 && byte < 128) || (byte == _CharCode.HT); |
| } |
| |
| static List<String> _tokenizeFieldValue(String headerValue) { |
| List<String> tokens = <String>[]; |
| int start = 0; |
| int index = 0; |
| while (index < headerValue.length) { |
| if (headerValue[index] == ",") { |
| tokens.add(headerValue.substring(start, index)); |
| start = index + 1; |
| } else if (headerValue[index] == " " || headerValue[index] == "\t") { |
| start++; |
| } |
| index++; |
| } |
| tokens.add(headerValue.substring(start, index)); |
| return tokens; |
| } |
| |
| static int _toLowerCaseByte(int x) { |
| // Optimized version: |
| // - 0x41 is 'A' |
| // - 0x7f is ASCII mask |
| // - 26 is the number of alpha characters. |
| // - 0x20 is the delta between lower and upper chars. |
| return (((x - 0x41) & 0x7f) < 26) ? (x | 0x20) : x; |
| } |
| |
| // expected should already be lowercase. |
| static bool _caseInsensitiveCompare(List<int> expected, List<int> value) { |
| if (expected.length != value.length) return false; |
| for (int i = 0; i < expected.length; i++) { |
| if (expected[i] != _toLowerCaseByte(value[i])) return false; |
| } |
| return true; |
| } |
| |
| void _expect(int val1, int val2) { |
| if (val1 != val2) { |
| throw HttpException("Failed to parse HTTP, $val1 does not match $val2"); |
| } |
| } |
| |
| int _expectHexDigit(int byte) { |
| if (0x30 <= byte && byte <= 0x39) { |
| return byte - 0x30; // 0 - 9 |
| } else if (0x41 <= byte && byte <= 0x46) { |
| return byte - 0x41 + 10; // A - F |
| } else if (0x61 <= byte && byte <= 0x66) { |
| return byte - 0x61 + 10; // a - f |
| } else { |
| throw HttpException( |
| "Failed to parse HTTP, $byte is expected to be a Hex digit"); |
| } |
| } |
| |
| void _addWithValidation(List<int> list, int byte) { |
| _headersReceivedSize++; |
| if (_headersReceivedSize < _headerTotalSizeLimit) { |
| list.add(byte); |
| } else { |
| _reportSizeLimitError(); |
| } |
| } |
| |
| void _reportSizeLimitError() { |
| String method = ""; |
| switch (_state) { |
| case _State.START: |
| case _State.METHOD_OR_RESPONSE_HTTP_VERSION: |
| case _State.REQUEST_LINE_METHOD: |
| method = "Method"; |
| break; |
| |
| case _State.REQUEST_LINE_URI: |
| method = "URI"; |
| break; |
| |
| case _State.RESPONSE_LINE_REASON_PHRASE: |
| method = "Reason phrase"; |
| break; |
| |
| case _State.HEADER_START: |
| case _State.HEADER_FIELD: |
| method = "Header field"; |
| break; |
| |
| case _State.HEADER_VALUE_START: |
| case _State.HEADER_VALUE: |
| method = "Header value"; |
| break; |
| |
| default: |
| throw UnsupportedError("Unexpected state: $_state"); |
| } |
| throw HttpException( |
| "$method exceeds the $_headerTotalSizeLimit size limit"); |
| } |
| |
| _HttpIncoming _createIncoming(int transferLength) { |
| assert(_incoming == null); |
| assert(_bodyController == null); |
| assert(!_bodyPaused); |
| var controller = _bodyController = StreamController<Uint8List>(sync: true); |
| var incoming = |
| _incoming = _HttpIncoming(_headers!, transferLength, controller.stream); |
| controller |
| ..onListen = () { |
| if (incoming != _incoming) return; |
| assert(_bodyPaused); |
| _bodyPaused = false; |
| _pauseStateChanged(); |
| } |
| ..onPause = () { |
| if (incoming != _incoming) return; |
| assert(!_bodyPaused); |
| _bodyPaused = true; |
| _pauseStateChanged(); |
| } |
| ..onResume = () { |
| if (incoming != _incoming) return; |
| assert(_bodyPaused); |
| _bodyPaused = false; |
| _pauseStateChanged(); |
| } |
| ..onCancel = () { |
| if (incoming != _incoming) return; |
| _socketSubscription?.cancel(); |
| _closeIncoming(true); |
| _controller.close(); |
| }; |
| _bodyPaused = true; |
| _pauseStateChanged(); |
| return incoming; |
| } |
| |
| void _closeIncoming([bool closing = false]) { |
| // Ignore multiple close (can happen in re-entrance). |
| var tmp = _incoming; |
| if (tmp == null) return; |
| tmp.close(closing); |
| _incoming = null; |
| var controller = _bodyController; |
| if (controller != null) { |
| controller.close(); |
| _bodyController = null; |
| } |
| _bodyPaused = false; |
| _pauseStateChanged(); |
| } |
| |
| void _pauseStateChanged() { |
| if (_incoming != null) { |
| if (!_bodyPaused && !_parserCalled) { |
| _parse(); |
| } |
| } else { |
| if (!_paused && !_parserCalled) { |
| _parse(); |
| } |
| } |
| } |
| |
| void _reportHttpError(error, [stackTrace]) { |
| _socketSubscription?.cancel(); |
| _state = _State.FAILURE; |
| _controller.addError(error, stackTrace); |
| _controller.close(); |
| } |
| |
| void _reportBodyError(error, [stackTrace]) { |
| _socketSubscription?.cancel(); |
| _state = _State.FAILURE; |
| _bodyController?.addError(error, stackTrace); |
| // In case of drain(), error event will close the stream. |
| _bodyController?.close(); |
| } |
| } |
