From 00fab1aaff63c488fb9986d6837842f2137b2b27 Mon Sep 17 00:00:00 2001 From: Khafra <42794878+KhafraDev@users.noreply.github.com> Date: Wed, 21 Dec 2022 22:30:16 -0500 Subject: [PATCH] fix(websocket): run parser in loop, instead of recursively --- lib/websocket/receiver.js | 309 +++++++++++++++++++------------------- 1 file changed, 156 insertions(+), 153 deletions(-) diff --git a/lib/websocket/receiver.js b/lib/websocket/receiver.js index 763f4454306..bdd2031b418 100644 --- a/lib/websocket/receiver.js +++ b/lib/websocket/receiver.js @@ -48,201 +48,204 @@ class ByteParser extends Writable { * or not enough bytes are buffered to parse. */ run (callback) { - if (this.#state === parserStates.INFO) { - // If there aren't enough bytes to parse the payload length, etc. - if (this.#byteOffset < 2) { - return callback() - } + while (true) { + if (this.#state === parserStates.INFO) { + // If there aren't enough bytes to parse the payload length, etc. + if (this.#byteOffset < 2) { + return callback() + } - const buffer = this.consume(2) + const buffer = this.consume(2) - this.#info.fin = (buffer[0] & 0x80) !== 0 - this.#info.opcode = buffer[0] & 0x0F + this.#info.fin = (buffer[0] & 0x80) !== 0 + this.#info.opcode = buffer[0] & 0x0F - // If we receive a fragmented message, we use the type of the first - // frame to parse the full message as binary/text, when it's terminated - this.#info.originalOpcode ??= this.#info.opcode + // If we receive a fragmented message, we use the type of the first + // frame to parse the full message as binary/text, when it's terminated + this.#info.originalOpcode ??= this.#info.opcode - this.#info.fragmented = !this.#info.fin && this.#info.opcode !== opcodes.CONTINUATION + this.#info.fragmented = !this.#info.fin && this.#info.opcode !== opcodes.CONTINUATION - if (this.#info.fragmented && this.#info.opcode !== opcodes.BINARY && this.#info.opcode !== opcodes.TEXT) { - // Only text and binary frames can be fragmented - failWebsocketConnection(this.ws, 'Invalid frame type was fragmented.') - return - } + if (this.#info.fragmented && this.#info.opcode !== opcodes.BINARY && this.#info.opcode !== opcodes.TEXT) { + // Only text and binary frames can be fragmented + failWebsocketConnection(this.ws, 'Invalid frame type was fragmented.') + return + } - const payloadLength = buffer[1] & 0x7F + const payloadLength = buffer[1] & 0x7F - if (payloadLength <= 125) { - this.#info.payloadLength = payloadLength - this.#state = parserStates.READ_DATA - } else if (payloadLength === 126) { - this.#state = parserStates.PAYLOADLENGTH_16 - } else if (payloadLength === 127) { - this.#state = parserStates.PAYLOADLENGTH_64 - } + if (payloadLength <= 125) { + this.#info.payloadLength = payloadLength + this.#state = parserStates.READ_DATA + } else if (payloadLength === 126) { + this.#state = parserStates.PAYLOADLENGTH_16 + } else if (payloadLength === 127) { + this.#state = parserStates.PAYLOADLENGTH_64 + } - if (this.#info.fragmented && payloadLength > 125) { - // A fragmented frame can't be fragmented itself - failWebsocketConnection(this.ws, 'Fragmented frame exceeded 125 bytes.') - return - } else if ( - (this.#info.opcode === opcodes.PING || - this.#info.opcode === opcodes.PONG || - this.#info.opcode === opcodes.CLOSE) && - payloadLength > 125 - ) { - // Control frames can have a payload length of 125 bytes MAX - failWebsocketConnection(this.ws, 'Payload length for control frame exceeded 125 bytes.') - return - } else if (this.#info.opcode === opcodes.CLOSE) { - if (payloadLength === 1) { - failWebsocketConnection(this.ws, 'Received close frame with a 1-byte body.') + if (this.#info.fragmented && payloadLength > 125) { + // A fragmented frame can't be fragmented itself + failWebsocketConnection(this.ws, 'Fragmented frame exceeded 125 bytes.') return - } + } else if ( + (this.#info.opcode === opcodes.PING || + this.#info.opcode === opcodes.PONG || + this.#info.opcode === opcodes.CLOSE) && + payloadLength > 125 + ) { + // Control frames can have a payload length of 125 bytes MAX + failWebsocketConnection(this.ws, 'Payload length for control frame exceeded 125 bytes.') + return + } else if (this.#info.opcode === opcodes.CLOSE) { + if (payloadLength === 1) { + failWebsocketConnection(this.ws, 'Received close frame with a 1-byte body.') + return + } - const body = this.consume(payloadLength) + const body = this.consume(payloadLength) + + this.#info.closeInfo = this.parseCloseBody(false, body) + + if (!this.ws[kSentClose]) { + // If an endpoint receives a Close frame and did not previously send a + // Close frame, the endpoint MUST send a Close frame in response. (When + // sending a Close frame in response, the endpoint typically echos the + // status code it received.) + const body = Buffer.allocUnsafe(2) + body.writeUInt16BE(this.#info.closeInfo.code, 0) + const closeFrame = new WebsocketFrameSend(body) + + this.ws[kResponse].socket.write( + closeFrame.createFrame(opcodes.CLOSE), + (err) => { + if (!err) { + this.ws[kSentClose] = true + } + } + ) + } - this.#info.closeInfo = this.parseCloseBody(false, body) + // Upon either sending or receiving a Close control frame, it is said + // that _The WebSocket Closing Handshake is Started_ and that the + // WebSocket connection is in the CLOSING state. + this.ws[kReadyState] = states.CLOSING + this.ws[kReceivedClose] = true - if (!this.ws[kSentClose]) { - // If an endpoint receives a Close frame and did not previously send a - // Close frame, the endpoint MUST send a Close frame in response. (When - // sending a Close frame in response, the endpoint typically echos the - // status code it received.) - const body = Buffer.allocUnsafe(2) - body.writeUInt16BE(this.#info.closeInfo.code, 0) - const closeFrame = new WebsocketFrameSend(body) + this.end() - this.ws[kResponse].socket.write( - closeFrame.createFrame(opcodes.CLOSE), - (err) => { - if (!err) { - this.ws[kSentClose] = true - } - } - ) - } + return + } else if (this.#info.opcode === opcodes.PING) { + // Upon receipt of a Ping frame, an endpoint MUST send a Pong frame in + // response, unless it already received a Close frame. + // A Pong frame sent in response to a Ping frame must have identical + // "Application data" + + const body = this.consume(payloadLength) - // Upon either sending or receiving a Close control frame, it is said - // that _The WebSocket Closing Handshake is Started_ and that the - // WebSocket connection is in the CLOSING state. - this.ws[kReadyState] = states.CLOSING - this.ws[kReceivedClose] = true + if (!this.ws[kReceivedClose]) { + const frame = new WebsocketFrameSend(body) - this.end() + this.ws[kResponse].socket.write(frame.createFrame(opcodes.PONG)) - return - } else if (this.#info.opcode === opcodes.PING) { - // Upon receipt of a Ping frame, an endpoint MUST send a Pong frame in - // response, unless it already received a Close frame. - // A Pong frame sent in response to a Ping frame must have identical - // "Application data" + if (channels.ping.hasSubscribers) { + channels.ping.publish({ + payload: body + }) + } + } - const body = this.consume(payloadLength) + this.#state = parserStates.INFO - if (!this.ws[kReceivedClose]) { - const frame = new WebsocketFrameSend(body) + if (this.#byteOffset > 0) { + continue + } else { + callback() + return + } + } else if (this.#info.opcode === opcodes.PONG) { + // A Pong frame MAY be sent unsolicited. This serves as a + // unidirectional heartbeat. A response to an unsolicited Pong frame is + // not expected. - this.ws[kResponse].socket.write(frame.createFrame(opcodes.PONG)) + const body = this.consume(payloadLength) - if (channels.ping.hasSubscribers) { - channels.ping.publish({ + if (channels.pong.hasSubscribers) { + channels.pong.publish({ payload: body }) } - } - - this.#state = parserStates.INFO - if (this.#byteOffset > 0) { - return this.run(callback) - } else { - callback() - return + if (this.#byteOffset > 0) { + continue + } else { + callback() + return + } + } + } else if (this.#state === parserStates.PAYLOADLENGTH_16) { + if (this.#byteOffset < 2) { + return callback() } - } else if (this.#info.opcode === opcodes.PONG) { - // A Pong frame MAY be sent unsolicited. This serves as a - // unidirectional heartbeat. A response to an unsolicited Pong frame is - // not expected. - const body = this.consume(payloadLength) + const buffer = this.consume(2) - if (channels.pong.hasSubscribers) { - channels.pong.publish({ - payload: body - }) + this.#info.payloadLength = buffer.readUInt16BE(0) + this.#state = parserStates.READ_DATA + } else if (this.#state === parserStates.PAYLOADLENGTH_64) { + if (this.#byteOffset < 8) { + return callback() } - if (this.#byteOffset > 0) { - return this.run(callback) - } else { - callback() + const buffer = this.consume(8) + const upper = buffer.readUInt32BE(0) + + // 2^31 is the maxinimum bytes an arraybuffer can contain + // on 32-bit systems. Although, on 64-bit systems, this is + // 2^53-1 bytes. + // https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Errors/Invalid_array_length + // https://source.chromium.org/chromium/chromium/src/+/main:v8/src/common/globals.h;drc=1946212ac0100668f14eb9e2843bdd846e510a1e;bpv=1;bpt=1;l=1275 + // https://source.chromium.org/chromium/chromium/src/+/main:v8/src/objects/js-array-buffer.h;l=34;drc=1946212ac0100668f14eb9e2843bdd846e510a1e + if (upper > 2 ** 31 - 1) { + failWebsocketConnection(this.ws, 'Received payload length > 2^31 bytes.') return } - } - } else if (this.#state === parserStates.PAYLOADLENGTH_16) { - if (this.#byteOffset < 2) { - return callback() - } - - const buffer = this.consume(2) - this.#info.payloadLength = buffer.readUInt16BE(0) - this.#state = parserStates.READ_DATA - } else if (this.#state === parserStates.PAYLOADLENGTH_64) { - if (this.#byteOffset < 8) { - return callback() - } - - const buffer = this.consume(8) - const upper = buffer.readUInt32BE(0) - - // 2^31 is the maxinimum bytes an arraybuffer can contain - // on 32-bit systems. Although, on 64-bit systems, this is - // 2^53-1 bytes. - // https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Errors/Invalid_array_length - // https://source.chromium.org/chromium/chromium/src/+/main:v8/src/common/globals.h;drc=1946212ac0100668f14eb9e2843bdd846e510a1e;bpv=1;bpt=1;l=1275 - // https://source.chromium.org/chromium/chromium/src/+/main:v8/src/objects/js-array-buffer.h;l=34;drc=1946212ac0100668f14eb9e2843bdd846e510a1e - if (upper > 2 ** 31 - 1) { - failWebsocketConnection(this.ws, 'Received payload length > 2^31 bytes.') - return - } + const lower = buffer.readUInt32BE(4) - const lower = buffer.readUInt32BE(4) + this.#info.payloadLength = (upper << 8) + lower + this.#state = parserStates.READ_DATA + } else if (this.#state === parserStates.READ_DATA) { + if (this.#byteOffset < this.#info.payloadLength) { + // If there is still more data in this chunk that needs to be read + return callback() + } else if (this.#byteOffset >= this.#info.payloadLength) { + // If the server sent multiple frames in a single chunk - this.#info.payloadLength = (upper << 8) + lower - this.#state = parserStates.READ_DATA - } else if (this.#state === parserStates.READ_DATA) { - if (this.#byteOffset < this.#info.payloadLength) { - // If there is still more data in this chunk that needs to be read - return callback() - } else if (this.#byteOffset >= this.#info.payloadLength) { - // If the server sent multiple frames in a single chunk + const body = this.consume(this.#info.payloadLength) - const body = this.consume(this.#info.payloadLength) + this.#fragments.push(body) - this.#fragments.push(body) + // If the frame is unfragmented, or a fragmented frame was terminated, + // a message was received + if (!this.#info.fragmented || (this.#info.fin && this.#info.opcode === opcodes.CONTINUATION)) { + const fullMessage = Buffer.concat(this.#fragments) - // If the frame is unfragmented, or a fragmented frame was terminated, - // a message was received - if (!this.#info.fragmented || (this.#info.fin && this.#info.opcode === opcodes.CONTINUATION)) { - const fullMessage = Buffer.concat(this.#fragments) + websocketMessageReceived(this.ws, this.#info.originalOpcode, fullMessage) - websocketMessageReceived(this.ws, this.#info.originalOpcode, fullMessage) + this.#info = {} + this.#fragments.length = 0 + } - this.#info = {} - this.#fragments.length = 0 + this.#state = parserStates.INFO } - - this.#state = parserStates.INFO } - } - if (this.#byteOffset > 0) { - return this.run(callback) - } else { - callback() + if (this.#byteOffset > 0) { + continue + } else { + callback() + break + } } }