websocket: fix parsing of control frames

lib/web/websocket/receiver.js

@@ -65,7 +65,9 @@ class ByteParser extends Writable {
 
         // 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 (this.#info.opcode === opcodes.BINARY || this.#info.opcode === opcodes.TEXT) {
+          this.#info.originalOpcode ??= this.#info.opcode
+        }
 
         this.#info.fragmented = !this.#info.fin && this.#info.opcode !== opcodes.CONTINUATION
 

test/websocket/issue-2859.js

@@ -0,0 +1,38 @@
+'use strict'
+
+const { test } = require('node:test')
+const { WebSocketServer } = require('ws')
+const { WebSocket } = require('../..')
+const diagnosticsChannel = require('node:diagnostics_channel')
+const { tspl } = require('@matteo.collina/tspl')
+
+test('Fragmented frame with a ping frame in the first of it', async (t) => {
+  const { completed, deepStrictEqual, strictEqual } = tspl(t, { plan: 2 })
+
+  const server = new WebSocketServer({ port: 0 })
+
+  server.on('connection', (ws) => {
+    const socket = ws._socket
+
+    socket.write(Buffer.from([0x89, 0x05, 0x48, 0x65, 0x6c, 0x6c, 0x6f])) // ping "Hello"
+    socket.write(Buffer.from([0x01, 0x03, 0x48, 0x65, 0x6c])) // Text frame "Hel"
+    socket.write(Buffer.from([0x80, 0x02, 0x6c, 0x6f])) // Text frame "lo"
+  })
+
+  t.after(() => {
+    server.close()
+    ws.close()
+  })
+
+  const ws = new WebSocket(`ws://127.0.0.1:${server.address().port}`)
+
+  diagnosticsChannel.channel('undici:websocket:ping').subscribe(
+    ({ payload }) => deepStrictEqual(payload, Buffer.from('Hello'))
+  )
+
+  ws.addEventListener('message', ({ data }) => {
+    strictEqual(data, 'Hello')
+  })
+
+  await completed
+})