Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

fix(websocket): run parser in loop, instead of recursively #1828

Merged
merged 1 commit into from
Dec 22, 2022
Merged

fix(websocket): run parser in loop, instead of recursively #1828

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Jump to
Jump to file
Failed to load files.
Diff view
Diff view
309 changes: 156 additions & 153 deletions lib/websocket/receiver.js
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -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
}
}
}

Expand Down