websocket: fix ByteParser.run and parseCloseBody

lib/web/websocket/receiver.js

@@ -108,7 +108,7 @@ class ByteParser extends Writable {
  // sending a Close frame in response, the endpoint typically echos the
  // status code it received.)
  let body = emptyBuffer
- if (this.#info.closeInfo.code) {
+ if (this.#info.closeInfo?.code) {
  body = Buffer.allocUnsafe(2)
  body.writeUInt16BE(this.#info.closeInfo.code, 0)
  }
@@ -298,26 +298,30 @@ class ByteParser extends Writable {
  // defined as the status code (Section 7.4) contained in the first Close
  // control frame received by the application
  code = data.readUInt16BE(0)
+ if (!isValidStatusCode(code)) {
+ return null
+ }
+ } else {
+ return null
  }
 
  // https://datatracker.ietf.org/doc/html/rfc6455#section-7.1.6
- /** @type {Buffer} */
- let reason = data.subarray(2)
+ /** @type {number} */
+ let reasonOffset = 2
 
- // Remove BOM
- if (reason[0] === 0xEF && reason[1] === 0xBB && reason[2] === 0xBF) {
- reason = reason.subarray(3)
+ // Detect BOM and ignore it
+ if (data.length >= 5 && data[2] === 0xEF && data[3] === 0xBB && data[4] === 0xBF) {
+ reasonOffset = 5
  }
 
- if (code !== undefined && !isValidStatusCode(code)) {
- return null
+ if (data.length - reasonOffset < 1) {
+ return { code, reason: '' }
  }
 
+ let reason = ''
  try {
- reason = utf8Decode(reason)
- } catch {
- return null
- }
+ reason = utf8Decode(data.subarray(reasonOffset))
+ } catch { }
 
  return { code, reason }
  }

test/websocket/receive.js

@@ -1,11 +1,13 @@
 'use strict'
 
+const { tspl } = require('@matteo.collina/tspl')
 const { test } = require('node:test')
-const assert = require('node:assert')
 const { WebSocketServer } = require('ws')
 const { WebSocket } = require('../..')
 
-test('Receiving a frame with a payload length > 2^31-1 bytes', () => {
+test('Receiving a frame with a payload length > 2^31-1 bytes', async (t) => {
+ t = tspl(t, { plan: 1 })
+
  const server = new WebSocketServer({ port: 0 })
 
  server.on('connection', (ws) => {
@@ -16,19 +18,20 @@ test('Receiving a frame with a payload length > 2^31-1 bytes', () => {
 
  const ws = new WebSocket(`ws://localhost:${server.address().port}`)
 
- return new Promise((resolve, reject) => {
- ws.onmessage = reject
+ ws.onmessage = t.fail
 
- ws.addEventListener('error', (event) => {
- assert.ok(event.error instanceof Error) // error event is emitted
- ws.close()
- server.close()
- resolve()
- })
+ ws.addEventListener('error', (event) => {
+ ws.close()
+ server.close()
+ t.ok(event.error instanceof Error) // error event is emitted
  })
+
+ await t.completed
 })
 
-test('Receiving an ArrayBuffer', () => {
+test('Receiving an ArrayBuffer', async (t) => {
+ t = tspl(t, { plan: 3 })
+
  const server = new WebSocketServer({ port: 0 })
 
  server.on('connection', (ws) => {
@@ -43,18 +46,44 @@ test('Receiving an ArrayBuffer', () => {
 
  ws.addEventListener('open', () => {
  ws.binaryType = 'what'
- assert.equal(ws.binaryType, 'blob')
+ t.strictEqual(ws.binaryType, 'blob')
 
  ws.binaryType = 'arraybuffer' // <--
  ws.send('Hello')
  })
 
- return new Promise((resolve) => {
- ws.addEventListener('message', ({ data }) => {
- assert.ok(data instanceof ArrayBuffer)
- assert.deepStrictEqual(Buffer.from(data), Buffer.from('Hello'))
- server.close()
- resolve()
+ ws.addEventListener('message', ({ data }) => {
+ t.ok(data instanceof ArrayBuffer)
+ t.deepStrictEqual(Buffer.from(data), Buffer.from('Hello'))
+ server.close()
+ })
+
+ await t.completed
+})
+
+test('Receiving a close reason', async (t) => {
+ t = tspl(t, { plan: 1 })
+
+ const server = new WebSocketServer({ port: 0 })
+
+ server.on('connection', (ws) => {
+ ws.on('message', (data, isBinary) => {
+ ws.send(data, { binary: true })
+
+ ws.close(1000, Buffer.from('\uFEFFGood Bye!'))
  })
  })
+
+ const ws = new WebSocket(`ws://localhost:${server.address().port}`)
+
+ ws.addEventListener('open', () => {
+ ws.send('Hello')
+ })
+
+ ws.addEventListener('close', ({ reason }) => {
+ t.strictEqual(reason, 'Good Bye!')
+ server.close()
+ })
+
+ await t.completed
 })