From ff56ba6a3aa7d7acbc305fe8ca678a8374645274 Mon Sep 17 00:00:00 2001
From: Tim Perry <pimterry@gmail.com>
Date: Mon, 14 Jun 2021 19:35:28 +0200
Subject: [PATCH 1/5] Attach error codes to all receiver errors

---
 lib/permessage-deflate.js            |   1 +
 lib/receiver.js                      | 138 +++++++++++++++++++++++----
 test/create-websocket-stream.test.js |   1 +
 test/receiver.test.js                |  22 +++++
 test/websocket.test.js               |   1 +
 5 files changed, 144 insertions(+), 19 deletions(-)

diff --git a/lib/permessage-deflate.js b/lib/permessage-deflate.js
index a8974b988..8229280f1 100644
--- a/lib/permessage-deflate.js
+++ b/lib/permessage-deflate.js
@@ -495,6 +495,7 @@ function inflateOnData(chunk) {
   }
 
   this[kError] = new RangeError('Max payload size exceeded');
+  this[kError].code = 'WS_ERR_INVALID_DATA_PAYLOAD_LENGTH';
   this[kError][kStatusCode] = 1009;
   this.removeListener('data', inflateOnData);
   this.reset();
diff --git a/lib/receiver.js b/lib/receiver.js
index 65a5ab45f..848a52561 100644
--- a/lib/receiver.js
+++ b/lib/receiver.js
@@ -168,14 +168,26 @@ class Receiver extends Writable {
 
     if ((buf[0] & 0x30) !== 0x00) {
       this._loop = false;
-      return error(RangeError, 'RSV2 and RSV3 must be clear', true, 1002);
+      return error(
+        RangeError,
+        'RSV2 and RSV3 must be clear',
+        true,
+        1002,
+        'WS_ERR_UNEXPECTED_RSV_2_3'
+      );
     }
 
     const compressed = (buf[0] & 0x40) === 0x40;
 
     if (compressed && !this._extensions[PerMessageDeflate.extensionName]) {
       this._loop = false;
-      return error(RangeError, 'RSV1 must be clear', true, 1002);
+      return error(
+        RangeError,
+        'RSV1 must be clear',
+        true,
+        1002,
+        'WS_ERR_UNEXPECTED_RSV_1'
+      );
     }
 
     this._fin = (buf[0] & 0x80) === 0x80;
@@ -185,31 +197,61 @@ class Receiver extends Writable {
     if (this._opcode === 0x00) {
       if (compressed) {
         this._loop = false;
-        return error(RangeError, 'RSV1 must be clear', true, 1002);
+        return error(
+          RangeError,
+          'RSV1 must be clear',
+          true,
+          1002,
+          'WS_ERR_UNEXPECTED_RSV_1'
+        );
       }
 
       if (!this._fragmented) {
         this._loop = false;
-        return error(RangeError, 'invalid opcode 0', true, 1002);
+        return error(
+          RangeError,
+          'invalid opcode 0',
+          true,
+          1002,
+          'WS_ERR_INVALID_OPCODE'
+        );
       }
 
       this._opcode = this._fragmented;
     } else if (this._opcode === 0x01 || this._opcode === 0x02) {
       if (this._fragmented) {
         this._loop = false;
-        return error(RangeError, `invalid opcode ${this._opcode}`, true, 1002);
+        return error(
+          RangeError,
+          `invalid opcode ${this._opcode}`,
+          true,
+          1002,
+          'WS_ERR_INVALID_OPCODE'
+        );
       }
 
       this._compressed = compressed;
     } else if (this._opcode > 0x07 && this._opcode < 0x0b) {
       if (!this._fin) {
         this._loop = false;
-        return error(RangeError, 'FIN must be set', true, 1002);
+        return error(
+          RangeError,
+          'FIN must be set',
+          true,
+          1002,
+          'WS_ERR_EXPECTED_FIN'
+        );
       }
 
       if (compressed) {
         this._loop = false;
-        return error(RangeError, 'RSV1 must be clear', true, 1002);
+        return error(
+          RangeError,
+          'RSV1 must be clear',
+          true,
+          1002,
+          'WS_ERR_UNEXPECTED_RSV_1'
+        );
       }
 
       if (this._payloadLength > 0x7d) {
@@ -218,12 +260,19 @@ class Receiver extends Writable {
           RangeError,
           `invalid payload length ${this._payloadLength}`,
           true,
-          1002
+          1002,
+          'WS_ERR_INVALID_CONTROL_PAYLOAD_LENGTH'
         );
       }
     } else {
       this._loop = false;
-      return error(RangeError, `invalid opcode ${this._opcode}`, true, 1002);
+      return error(
+        RangeError,
+        `invalid opcode ${this._opcode}`,
+        true,
+        1002,
+        'WS_ERR_INVALID_OPCODE'
+      );
     }
 
     if (!this._fin && !this._fragmented) this._fragmented = this._opcode;
@@ -232,11 +281,23 @@ class Receiver extends Writable {
     if (this._isServer) {
       if (!this._masked) {
         this._loop = false;
-        return error(RangeError, 'MASK must be set', true, 1002);
+        return error(
+          RangeError,
+          'MASK must be set',
+          true,
+          1002,
+          'WS_ERR_EXPECTED_MASK'
+        );
       }
     } else if (this._masked) {
       this._loop = false;
-      return error(RangeError, 'MASK must be clear', true, 1002);
+      return error(
+        RangeError,
+        'MASK must be clear',
+        true,
+        1002,
+        'WS_ERR_UNEXPECTED_MASK'
+      );
     }
 
     if (this._payloadLength === 126) this._state = GET_PAYLOAD_LENGTH_16;
@@ -285,7 +346,8 @@ class Receiver extends Writable {
         RangeError,
         'Unsupported WebSocket frame: payload length > 2^53 - 1',
         false,
-        1009
+        1009,
+        'WS_ERR_INVALID_DATA_PAYLOAD_LENGTH'
       );
     }
 
@@ -304,7 +366,13 @@ class Receiver extends Writable {
       this._totalPayloadLength += this._payloadLength;
       if (this._totalPayloadLength > this._maxPayload && this._maxPayload > 0) {
         this._loop = false;
-        return error(RangeError, 'Max payload size exceeded', false, 1009);
+        return error(
+          RangeError,
+          'Max payload size exceeded',
+          false,
+          1009,
+          'WS_ERR_INVALID_DATA_PAYLOAD_LENGTH'
+        );
       }
     }
 
@@ -384,7 +452,13 @@ class Receiver extends Writable {
         this._messageLength += buf.length;
         if (this._messageLength > this._maxPayload && this._maxPayload > 0) {
           return cb(
-            error(RangeError, 'Max payload size exceeded', false, 1009)
+            error(
+              RangeError,
+              'Max payload size exceeded',
+              false,
+              1009,
+              'WS_ERR_INVALID_DATA_PAYLOAD_LENGTH'
+            )
           );
         }
 
@@ -431,7 +505,13 @@ class Receiver extends Writable {
 
         if (!isValidUTF8(buf)) {
           this._loop = false;
-          return error(Error, 'invalid UTF-8 sequence', true, 1007);
+          return error(
+            Error,
+            'invalid UTF-8 sequence',
+            true,
+            1007,
+            'WS_ERR_INVALID_UTF8'
+          );
         }
 
         this.emit('message', buf.toString());
@@ -456,18 +536,36 @@ class Receiver extends Writable {
         this.emit('conclude', 1005, '');
         this.end();
       } else if (data.length === 1) {
-        return error(RangeError, 'invalid payload length 1', true, 1002);
+        return error(
+          RangeError,
+          'invalid payload length 1',
+          true,
+          1002,
+          'WS_ERR_INVALID_CONTROL_PAYLOAD_LENGTH'
+        );
       } else {
         const code = data.readUInt16BE(0);
 
         if (!isValidStatusCode(code)) {
-          return error(RangeError, `invalid status code ${code}`, true, 1002);
+          return error(
+            RangeError,
+            `invalid status code ${code}`,
+            true,
+            1002,
+            'WS_ERR_INVALID_CLOSE_CODE'
+          );
         }
 
         const buf = data.slice(2);
 
         if (!isValidUTF8(buf)) {
-          return error(Error, 'invalid UTF-8 sequence', true, 1007);
+          return error(
+            Error,
+            'invalid UTF-8 sequence',
+            true,
+            1007,
+            'WS_ERR_INVALID_UTF8'
+          );
         }
 
         this.emit('conclude', code, buf.toString());
@@ -493,15 +591,17 @@ module.exports = Receiver;
  * @param {Boolean} prefix Specifies whether or not to add a default prefix to
  *     `message`
  * @param {Number} statusCode The status code
+ * @param {String} errorCode The exposed error code
  * @return {(Error|RangeError)} The error
  * @private
  */
-function error(ErrorCtor, message, prefix, statusCode) {
+function error(ErrorCtor, message, prefix, statusCode, errorCode) {
   const err = new ErrorCtor(
     prefix ? `Invalid WebSocket frame: ${message}` : message
   );
 
   Error.captureStackTrace(err, error);
+  err.code = errorCode;
   err[kStatusCode] = statusCode;
   return err;
 }
diff --git a/test/create-websocket-stream.test.js b/test/create-websocket-stream.test.js
index ddccb56b2..bcd240974 100644
--- a/test/create-websocket-stream.test.js
+++ b/test/create-websocket-stream.test.js
@@ -210,6 +210,7 @@ describe('createWebSocketStream', () => {
 
         duplex.on('error', (err) => {
           assert.ok(err instanceof RangeError);
+          assert.strictEqual(err.code, 'WS_ERR_INVALID_OPCODE');
           assert.strictEqual(
             err.message,
             'Invalid WebSocket frame: invalid opcode 5'
diff --git a/test/receiver.test.js b/test/receiver.test.js
index a70cc8dbe..54f32b04b 100644
--- a/test/receiver.test.js
+++ b/test/receiver.test.js
@@ -513,6 +513,7 @@ describe('Receiver', () => {
 
     receiver.on('error', (err) => {
       assert.ok(err instanceof RangeError);
+      assert.strictEqual(err.code, 'WS_ERR_UNEXPECTED_RSV_1');
       assert.strictEqual(
         err.message,
         'Invalid WebSocket frame: RSV1 must be clear'
@@ -534,6 +535,7 @@ describe('Receiver', () => {
 
     receiver.on('error', (err) => {
       assert.ok(err instanceof RangeError);
+      assert.strictEqual(err.code, 'WS_ERR_UNEXPECTED_RSV_1');
       assert.strictEqual(
         err.message,
         'Invalid WebSocket frame: RSV1 must be clear'
@@ -550,6 +552,7 @@ describe('Receiver', () => {
 
     receiver.on('error', (err) => {
       assert.ok(err instanceof RangeError);
+      assert.strictEqual(err.code, 'WS_ERR_UNEXPECTED_RSV_2_3');
       assert.strictEqual(
         err.message,
         'Invalid WebSocket frame: RSV2 and RSV3 must be clear'
@@ -566,6 +569,7 @@ describe('Receiver', () => {
 
     receiver.on('error', (err) => {
       assert.ok(err instanceof RangeError);
+      assert.strictEqual(err.code, 'WS_ERR_UNEXPECTED_RSV_2_3');
       assert.strictEqual(
         err.message,
         'Invalid WebSocket frame: RSV2 and RSV3 must be clear'
@@ -582,6 +586,7 @@ describe('Receiver', () => {
 
     receiver.on('error', (err) => {
       assert.ok(err instanceof RangeError);
+      assert.strictEqual(err.code, 'WS_ERR_INVALID_OPCODE');
       assert.strictEqual(
         err.message,
         'Invalid WebSocket frame: invalid opcode 0'
@@ -598,6 +603,7 @@ describe('Receiver', () => {
 
     receiver.on('error', (err) => {
       assert.ok(err instanceof RangeError);
+      assert.strictEqual(err.code, 'WS_ERR_INVALID_OPCODE');
       assert.strictEqual(
         err.message,
         'Invalid WebSocket frame: invalid opcode 1'
@@ -615,6 +621,7 @@ describe('Receiver', () => {
 
     receiver.on('error', (err) => {
       assert.ok(err instanceof RangeError);
+      assert.strictEqual(err.code, 'WS_ERR_INVALID_OPCODE');
       assert.strictEqual(
         err.message,
         'Invalid WebSocket frame: invalid opcode 2'
@@ -632,6 +639,7 @@ describe('Receiver', () => {
 
     receiver.on('error', (err) => {
       assert.ok(err instanceof RangeError);
+      assert.strictEqual(err.code, 'WS_ERR_EXPECTED_FIN');
       assert.strictEqual(
         err.message,
         'Invalid WebSocket frame: FIN must be set'
@@ -653,6 +661,7 @@ describe('Receiver', () => {
 
     receiver.on('error', (err) => {
       assert.ok(err instanceof RangeError);
+      assert.strictEqual(err.code, 'WS_ERR_UNEXPECTED_RSV_1');
       assert.strictEqual(
         err.message,
         'Invalid WebSocket frame: RSV1 must be clear'
@@ -669,6 +678,7 @@ describe('Receiver', () => {
 
     receiver.on('error', (err) => {
       assert.ok(err instanceof RangeError);
+      assert.strictEqual(err.code, 'WS_ERR_EXPECTED_FIN');
       assert.strictEqual(
         err.message,
         'Invalid WebSocket frame: FIN must be set'
@@ -685,6 +695,7 @@ describe('Receiver', () => {
 
     receiver.on('error', (err) => {
       assert.ok(err instanceof RangeError);
+      assert.strictEqual(err.code, 'WS_ERR_EXPECTED_MASK');
       assert.strictEqual(
         err.message,
         'Invalid WebSocket frame: MASK must be set'
@@ -701,6 +712,7 @@ describe('Receiver', () => {
 
     receiver.on('error', (err) => {
       assert.ok(err instanceof RangeError);
+      assert.strictEqual(err.code, 'WS_ERR_UNEXPECTED_MASK');
       assert.strictEqual(
         err.message,
         'Invalid WebSocket frame: MASK must be clear'
@@ -719,6 +731,7 @@ describe('Receiver', () => {
 
     receiver.on('error', (err) => {
       assert.ok(err instanceof RangeError);
+      assert.strictEqual(err.code, 'WS_ERR_INVALID_CONTROL_PAYLOAD_LENGTH');
       assert.strictEqual(
         err.message,
         'Invalid WebSocket frame: invalid payload length 126'
@@ -735,6 +748,7 @@ describe('Receiver', () => {
 
     receiver.on('error', (err) => {
       assert.ok(err instanceof RangeError);
+      assert.strictEqual(err.code, 'WS_ERR_INVALID_DATA_PAYLOAD_LENGTH');
       assert.strictEqual(
         err.message,
         'Unsupported WebSocket frame: payload length > 2^53 - 1'
@@ -756,6 +770,7 @@ describe('Receiver', () => {
 
     receiver.on('error', (err) => {
       assert.ok(err instanceof Error);
+      assert.strictEqual(err.code, 'WS_ERR_INVALID_UTF8');
       assert.strictEqual(
         err.message,
         'Invalid WebSocket frame: invalid UTF-8 sequence'
@@ -778,6 +793,7 @@ describe('Receiver', () => {
 
     receiver.on('error', (err) => {
       assert.ok(err instanceof Error);
+      assert.strictEqual(err.code, 'WS_ERR_INVALID_UTF8');
       assert.strictEqual(
         err.message,
         'Invalid WebSocket frame: invalid UTF-8 sequence'
@@ -799,6 +815,7 @@ describe('Receiver', () => {
 
     receiver.on('error', (err) => {
       assert.ok(err instanceof RangeError);
+      assert.strictEqual(err.code, 'WS_ERR_INVALID_CONTROL_PAYLOAD_LENGTH');
       assert.strictEqual(
         err.message,
         'Invalid WebSocket frame: invalid payload length 1'
@@ -815,6 +832,7 @@ describe('Receiver', () => {
 
     receiver.on('error', (err) => {
       assert.ok(err instanceof RangeError);
+      assert.strictEqual(err.code, 'WS_ERR_INVALID_CLOSE_CODE');
       assert.strictEqual(
         err.message,
         'Invalid WebSocket frame: invalid status code 0'
@@ -831,6 +849,7 @@ describe('Receiver', () => {
 
     receiver.on('error', (err) => {
       assert.ok(err instanceof Error);
+      assert.strictEqual(err.code, 'WS_ERR_INVALID_UTF8');
       assert.strictEqual(
         err.message,
         'Invalid WebSocket frame: invalid UTF-8 sequence'
@@ -860,6 +879,7 @@ describe('Receiver', () => {
 
     receiver.on('error', (err) => {
       assert.ok(err instanceof RangeError);
+      assert.strictEqual(err.code, 'WS_ERR_INVALID_DATA_PAYLOAD_LENGTH');
       assert.strictEqual(err.message, 'Max payload size exceeded');
       assert.strictEqual(err[kStatusCode], 1009);
       done();
@@ -884,6 +904,7 @@ describe('Receiver', () => {
 
     receiver.on('error', (err) => {
       assert.ok(err instanceof RangeError);
+      assert.strictEqual(err.code, 'WS_ERR_INVALID_DATA_PAYLOAD_LENGTH');
       assert.strictEqual(err.message, 'Max payload size exceeded');
       assert.strictEqual(err[kStatusCode], 1009);
       done();
@@ -913,6 +934,7 @@ describe('Receiver', () => {
 
     receiver.on('error', (err) => {
       assert.ok(err instanceof RangeError);
+      assert.strictEqual(err.code, 'WS_ERR_INVALID_DATA_PAYLOAD_LENGTH');
       assert.strictEqual(err.message, 'Max payload size exceeded');
       assert.strictEqual(err[kStatusCode], 1009);
       done();
diff --git a/test/websocket.test.js b/test/websocket.test.js
index a0557980e..03f984fcb 100644
--- a/test/websocket.test.js
+++ b/test/websocket.test.js
@@ -435,6 +435,7 @@ describe('WebSocket', () => {
 
         ws.on('error', (err) => {
           assert.ok(err instanceof RangeError);
+          assert.strictEqual(err.code, 'WS_ERR_INVALID_OPCODE');
           assert.strictEqual(
             err.message,
             'Invalid WebSocket frame: invalid opcode 5'

From 12e9995a05bbe46fe31be905db75abe6b3947536 Mon Sep 17 00:00:00 2001
From: Tim Perry <pimterry@gmail.com>
Date: Mon, 14 Jun 2021 20:39:44 +0200
Subject: [PATCH 2/5] Add docs for error codes

---
 doc/ws.md | 57 ++++++++++++++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 56 insertions(+), 1 deletion(-)

diff --git a/doc/ws.md b/doc/ws.md
index de62e6756..08c483072 100644
--- a/doc/ws.md
+++ b/doc/ws.md
@@ -44,6 +44,17 @@
   - [websocket.terminate()](#websocketterminate)
   - [websocket.url](#websocketurl)
 - [WebSocket.createWebSocketStream(websocket[, options])](#websocketcreatewebsocketstreamwebsocket-options)
+- [WS Error Codes](#ws-error-codes)
+  - [WS_ERR_INVALID_DATA_PAYLOAD_LENGTH](#wserrinvaliddatapayloadlength)
+  - [WS_ERR_INVALID_CONTROL_PAYLOAD_LENGTH](#wserrinvalidcontrolpayloadlength)
+  - [WS_ERR_INVALID_UTF8](#wserrinvalidutf8)
+  - [WS_ERR_INVALID_OPCODE](#wserrinvalidopcode)
+  - [WS_ERR_INVALID_CLOSE_CODE](#wserrinvalidclosecode)
+  - [WS_ERR_UNEXPECTED_RSV_1](#wserrunexpectedrsv1)
+  - [WS_ERR_UNEXPECTED_RSV_2_3](#wserrunexpectedrsv23)
+  - [WS_ERR_EXPECTED_FIN](#wserrexpectedfin)
+  - [WS_ERR_EXPECTED_MASK](#wserrexpectedmask)
+  - [WS_ERR_UNEXPECTED_MASK](#wserrunexpectedmask)
 
 ## Class: WebSocket.Server
 
@@ -298,7 +309,7 @@ human-readable string explaining why the connection has been closed.
 
 - `error` {Error}
 
-Emitted when an error occurs.
+Emitted when an error occurs. Errors may have a `.code` property, matching one of the string values defined below under [WS Error Codes](#ws-error-codes).
 
 ### Event: 'message'
 
@@ -493,6 +504,50 @@ The URL of the WebSocket server. Server clients don't have this attribute.
 Returns a `Duplex` stream that allows to use the Node.js streams API on top of a
 given `WebSocket`.
 
+## WS Error Codes
+
+Errors emitted by the websocket may have a `.code` property, describing the specific type of error that has occurred:
+
+### WS_ERR_INVALID_DATA_PAYLOAD_LENGTH
+
+A data frame with an unexpectedly long payload was received.
+
+### WS_ERR_INVALID_CONTROL_PAYLOAD_LENGTH
+
+A control frame with an unexpectedly long payload was received.
+
+### WS_ERR_INVALID_UTF8
+
+A text frame was received containing invalid UTF-8 data.
+
+### WS_ERR_INVALID_OPCODE
+
+A WebSocket frame was received with an invalid opcode.
+
+### WS_ERR_INVALID_CLOSE_CODE
+
+A WebSocket close frame was received with an invalid close code.
+
+### WS_ERR_UNEXPECTED_RSV_1
+
+A WebSocket frame was received with the RSV 1 bit set unexpectedly.
+
+### WS_ERR_UNEXPECTED_RSV_2_3
+
+A WebSocket frame was received with the RSV 2 or 3 bits set unexpectedly.
+
+### WS_ERR_EXPECTED_FIN
+
+A WebSocket frame was received with the FIN bit not set when it was expected.
+
+### WS_ERR_EXPECTED_MASK
+
+An unmasked WebSocket frame was received by a WebSocket server.
+
+### WS_ERR_UNEXPECTED_MASK
+
+A masked WebSocket frame was received by a WebSocket client.
+
 [concurrency-limit]: https://github.com/websockets/ws/issues/1202
 [duplex-options]:
   https://nodejs.org/api/stream.html#stream_new_stream_duplex_options

From c8187263547186089e747be5777fa56d2d8311d3 Mon Sep 17 00:00:00 2001
From: Tim Perry <pimterry@gmail.com>
Date: Tue, 15 Jun 2021 11:53:16 +0200
Subject: [PATCH 3/5] Change 'invalid data payload' error code to 'unsupported
 message'

It's not technically invalid - the standard does not disallow the length
that's used - it's just that this specific endpoint won't accept it.

It's also not necessarily a single data payload - the total length might
come from a series of separate data frames comprising a single message.
---
 doc/ws.md                 | 13 ++++++++-----
 lib/permessage-deflate.js |  2 +-
 lib/receiver.js           |  6 +++---
 test/receiver.test.js     |  8 ++++----
 4 files changed, 16 insertions(+), 13 deletions(-)

diff --git a/doc/ws.md b/doc/ws.md
index 08c483072..118e4d55c 100644
--- a/doc/ws.md
+++ b/doc/ws.md
@@ -45,7 +45,7 @@
   - [websocket.url](#websocketurl)
 - [WebSocket.createWebSocketStream(websocket[, options])](#websocketcreatewebsocketstreamwebsocket-options)
 - [WS Error Codes](#ws-error-codes)
-  - [WS_ERR_INVALID_DATA_PAYLOAD_LENGTH](#wserrinvaliddatapayloadlength)
+  - [WS_ERR_UNSUPPORTED_MESSAGE_LENGTH](#wserrunsupporteddatapayloadlength)
   - [WS_ERR_INVALID_CONTROL_PAYLOAD_LENGTH](#wserrinvalidcontrolpayloadlength)
   - [WS_ERR_INVALID_UTF8](#wserrinvalidutf8)
   - [WS_ERR_INVALID_OPCODE](#wserrinvalidopcode)
@@ -309,7 +309,8 @@ human-readable string explaining why the connection has been closed.
 
 - `error` {Error}
 
-Emitted when an error occurs. Errors may have a `.code` property, matching one of the string values defined below under [WS Error Codes](#ws-error-codes).
+Emitted when an error occurs. Errors may have a `.code` property, matching one
+of the string values defined below under [WS Error Codes](#ws-error-codes).
 
 ### Event: 'message'
 
@@ -506,11 +507,13 @@ given `WebSocket`.
 
 ## WS Error Codes
 
-Errors emitted by the websocket may have a `.code` property, describing the specific type of error that has occurred:
+Errors emitted by the websocket may have a `.code` property, describing the
+specific type of error that has occurred:
 
-### WS_ERR_INVALID_DATA_PAYLOAD_LENGTH
+### WS_ERR_UNSUPPORTED_MESSAGE_LENGTH
 
-A data frame with an unexpectedly long payload was received.
+A message was received with a length longer than the maximum supported length
+for this endpoint.
 
 ### WS_ERR_INVALID_CONTROL_PAYLOAD_LENGTH
 
diff --git a/lib/permessage-deflate.js b/lib/permessage-deflate.js
index 8229280f1..ce9178429 100644
--- a/lib/permessage-deflate.js
+++ b/lib/permessage-deflate.js
@@ -495,7 +495,7 @@ function inflateOnData(chunk) {
   }
 
   this[kError] = new RangeError('Max payload size exceeded');
-  this[kError].code = 'WS_ERR_INVALID_DATA_PAYLOAD_LENGTH';
+  this[kError].code = 'WS_ERR_UNSUPPORTED_MESSAGE_LENGTH';
   this[kError][kStatusCode] = 1009;
   this.removeListener('data', inflateOnData);
   this.reset();
diff --git a/lib/receiver.js b/lib/receiver.js
index 848a52561..e32676b1e 100644
--- a/lib/receiver.js
+++ b/lib/receiver.js
@@ -347,7 +347,7 @@ class Receiver extends Writable {
         'Unsupported WebSocket frame: payload length > 2^53 - 1',
         false,
         1009,
-        'WS_ERR_INVALID_DATA_PAYLOAD_LENGTH'
+        'WS_ERR_UNSUPPORTED_MESSAGE_LENGTH'
       );
     }
 
@@ -371,7 +371,7 @@ class Receiver extends Writable {
           'Max payload size exceeded',
           false,
           1009,
-          'WS_ERR_INVALID_DATA_PAYLOAD_LENGTH'
+          'WS_ERR_UNSUPPORTED_MESSAGE_LENGTH'
         );
       }
     }
@@ -457,7 +457,7 @@ class Receiver extends Writable {
               'Max payload size exceeded',
               false,
               1009,
-              'WS_ERR_INVALID_DATA_PAYLOAD_LENGTH'
+              'WS_ERR_UNSUPPORTED_MESSAGE_LENGTH'
             )
           );
         }
diff --git a/test/receiver.test.js b/test/receiver.test.js
index 54f32b04b..07fded28a 100644
--- a/test/receiver.test.js
+++ b/test/receiver.test.js
@@ -748,7 +748,7 @@ describe('Receiver', () => {
 
     receiver.on('error', (err) => {
       assert.ok(err instanceof RangeError);
-      assert.strictEqual(err.code, 'WS_ERR_INVALID_DATA_PAYLOAD_LENGTH');
+      assert.strictEqual(err.code, 'WS_ERR_UNSUPPORTED_MESSAGE_LENGTH');
       assert.strictEqual(
         err.message,
         'Unsupported WebSocket frame: payload length > 2^53 - 1'
@@ -879,7 +879,7 @@ describe('Receiver', () => {
 
     receiver.on('error', (err) => {
       assert.ok(err instanceof RangeError);
-      assert.strictEqual(err.code, 'WS_ERR_INVALID_DATA_PAYLOAD_LENGTH');
+      assert.strictEqual(err.code, 'WS_ERR_UNSUPPORTED_MESSAGE_LENGTH');
       assert.strictEqual(err.message, 'Max payload size exceeded');
       assert.strictEqual(err[kStatusCode], 1009);
       done();
@@ -904,7 +904,7 @@ describe('Receiver', () => {
 
     receiver.on('error', (err) => {
       assert.ok(err instanceof RangeError);
-      assert.strictEqual(err.code, 'WS_ERR_INVALID_DATA_PAYLOAD_LENGTH');
+      assert.strictEqual(err.code, 'WS_ERR_UNSUPPORTED_MESSAGE_LENGTH');
       assert.strictEqual(err.message, 'Max payload size exceeded');
       assert.strictEqual(err[kStatusCode], 1009);
       done();
@@ -934,7 +934,7 @@ describe('Receiver', () => {
 
     receiver.on('error', (err) => {
       assert.ok(err instanceof RangeError);
-      assert.strictEqual(err.code, 'WS_ERR_INVALID_DATA_PAYLOAD_LENGTH');
+      assert.strictEqual(err.code, 'WS_ERR_UNSUPPORTED_MESSAGE_LENGTH');
       assert.strictEqual(err.message, 'Max payload size exceeded');
       assert.strictEqual(err[kStatusCode], 1009);
       done();

From 11954cc941915f12b1af7321b231abf3d6619ded Mon Sep 17 00:00:00 2001
From: Tim Perry <pimterry@gmail.com>
Date: Tue, 15 Jun 2021 14:46:11 +0200
Subject: [PATCH 4/5] Add an separate WS_ERR_UNSUPPORTED_DATA_PAYLOAD_LENGTH
 error code

---
 doc/ws.md             | 11 ++++++++---
 lib/receiver.js       |  2 +-
 test/receiver.test.js |  2 +-
 3 files changed, 10 insertions(+), 5 deletions(-)

diff --git a/doc/ws.md b/doc/ws.md
index 118e4d55c..7fede7246 100644
--- a/doc/ws.md
+++ b/doc/ws.md
@@ -512,12 +512,17 @@ specific type of error that has occurred:
 
 ### WS_ERR_UNSUPPORTED_MESSAGE_LENGTH
 
-A message was received with a length longer than the maximum supported length
-for this endpoint.
+A message was received with a length longer than the maximum supported length,
+as configured by the `maxPayload` option.
+
+### WS_ERR_UNSUPPORTED_DATA_PAYLOAD_LENGTH
+
+A data frame was received with a length longer the max supported length (2^53-1,
+due to JavaScript language limitations).
 
 ### WS_ERR_INVALID_CONTROL_PAYLOAD_LENGTH
 
-A control frame with an unexpectedly long payload was received.
+A control frame with an invalid payload length was received.
 
 ### WS_ERR_INVALID_UTF8
 
diff --git a/lib/receiver.js b/lib/receiver.js
index e32676b1e..7ed992214 100644
--- a/lib/receiver.js
+++ b/lib/receiver.js
@@ -347,7 +347,7 @@ class Receiver extends Writable {
         'Unsupported WebSocket frame: payload length > 2^53 - 1',
         false,
         1009,
-        'WS_ERR_UNSUPPORTED_MESSAGE_LENGTH'
+        'WS_ERR_UNSUPPORTED_DATA_PAYLOAD_LENGTH'
       );
     }
 
diff --git a/test/receiver.test.js b/test/receiver.test.js
index 07fded28a..cd5770dfb 100644
--- a/test/receiver.test.js
+++ b/test/receiver.test.js
@@ -748,7 +748,7 @@ describe('Receiver', () => {
 
     receiver.on('error', (err) => {
       assert.ok(err instanceof RangeError);
-      assert.strictEqual(err.code, 'WS_ERR_UNSUPPORTED_MESSAGE_LENGTH');
+      assert.strictEqual(err.code, 'WS_ERR_UNSUPPORTED_DATA_PAYLOAD_LENGTH');
       assert.strictEqual(
         err.message,
         'Unsupported WebSocket frame: payload length > 2^53 - 1'

From 2acd3cb2a2bc29c880736a2587e5d2b702750423 Mon Sep 17 00:00:00 2001
From: Tim Perry <pimterry@gmail.com>
Date: Tue, 15 Jun 2021 06:16:13 -0700
Subject: [PATCH 5/5] Update error docs from review suggestions

Co-authored-by: Luigi Pinca <luigipinca@gmail.com>
---
 doc/ws.md | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/doc/ws.md b/doc/ws.md
index 7fede7246..7212a1c01 100644
--- a/doc/ws.md
+++ b/doc/ws.md
@@ -46,6 +46,7 @@
 - [WebSocket.createWebSocketStream(websocket[, options])](#websocketcreatewebsocketstreamwebsocket-options)
 - [WS Error Codes](#ws-error-codes)
   - [WS_ERR_UNSUPPORTED_MESSAGE_LENGTH](#wserrunsupporteddatapayloadlength)
+  - [WS_ERR_UNSUPPORTED_DATA_PAYLOAD_LENGTH](#wserrunsupporteddatapayloadlength)
   - [WS_ERR_INVALID_CONTROL_PAYLOAD_LENGTH](#wserrinvalidcontrolpayloadlength)
   - [WS_ERR_INVALID_UTF8](#wserrinvalidutf8)
   - [WS_ERR_INVALID_OPCODE](#wserrinvalidopcode)
@@ -526,7 +527,7 @@ A control frame with an invalid payload length was received.
 
 ### WS_ERR_INVALID_UTF8
 
-A text frame was received containing invalid UTF-8 data.
+A text or close frame was received containing invalid UTF-8 data.
 
 ### WS_ERR_INVALID_OPCODE
 
@@ -538,11 +539,11 @@ A WebSocket close frame was received with an invalid close code.
 
 ### WS_ERR_UNEXPECTED_RSV_1
 
-A WebSocket frame was received with the RSV 1 bit set unexpectedly.
+A WebSocket frame was received with the RSV1 bit set unexpectedly.
 
 ### WS_ERR_UNEXPECTED_RSV_2_3
 
-A WebSocket frame was received with the RSV 2 or 3 bits set unexpectedly.
+A WebSocket frame was received with the RSV2 or RSV3 bit set unexpectedly.
 
 ### WS_ERR_EXPECTED_FIN