tor-browser

receiver.test.js (29836B)

---

'use strict';

const assert = require('assert');
const crypto = require('crypto');

const PerMessageDeflate = require('../lib/permessage-deflate');
const Receiver = require('../lib/receiver');
const Sender = require('../lib/sender');
const { EMPTY_BUFFER, kStatusCode } = require('../lib/constants');

describe('Receiver', () => {
 it('parses an unmasked text message', (done) => {
   const receiver = new Receiver();

   receiver.on('message', (data, isBinary) => {
     assert.deepStrictEqual(data, Buffer.from('Hello'));
     assert.ok(!isBinary);
     done();
   });

   receiver.write(Buffer.from('810548656c6c6f', 'hex'));
 });

 it('parses a close message', (done) => {
   const receiver = new Receiver();

   receiver.on('conclude', (code, data) => {
     assert.strictEqual(code, 1005);
     assert.strictEqual(data, EMPTY_BUFFER);
     done();
   });

   receiver.write(Buffer.from('8800', 'hex'));
 });

 it('parses a close message spanning multiple writes', (done) => {
   const receiver = new Receiver();

   receiver.on('conclude', (code, data) => {
     assert.strictEqual(code, 1000);
     assert.deepStrictEqual(data, Buffer.from('DONE'));
     done();
   });

   receiver.write(Buffer.from('8806', 'hex'));
   receiver.write(Buffer.from('03e8444F4E45', 'hex'));
 });

 it('parses a masked text message', (done) => {
   const receiver = new Receiver({ isServer: true });

   receiver.on('message', (data, isBinary) => {
     assert.deepStrictEqual(data, Buffer.from('5:::{"name":"echo"}'));
     assert.ok(!isBinary);
     done();
   });

   receiver.write(
     Buffer.from('81933483a86801b992524fa1c60959e68a5216e6cb005ba1d5', 'hex')
   );
 });

 it('parses a masked text message longer than 125 B', (done) => {
   const receiver = new Receiver({ isServer: true });
   const msg = Buffer.from('A'.repeat(200));

   const list = Sender.frame(msg, {
     fin: true,
     rsv1: false,
     opcode: 0x01,
     mask: true,
     readOnly: true
   });

   const frame = Buffer.concat(list);

   receiver.on('message', (data, isBinary) => {
     assert.deepStrictEqual(data, msg);
     assert.ok(!isBinary);
     done();
   });

   receiver.write(frame.slice(0, 2));
   setImmediate(() => receiver.write(frame.slice(2)));
 });

 it('parses a really long masked text message', (done) => {
   const receiver = new Receiver({ isServer: true });
   const msg = Buffer.from('A'.repeat(64 * 1024));

   const list = Sender.frame(msg, {
     fin: true,
     rsv1: false,
     opcode: 0x01,
     mask: true,
     readOnly: true
   });

   const frame = Buffer.concat(list);

   receiver.on('message', (data, isBinary) => {
     assert.deepStrictEqual(data, msg);
     assert.ok(!isBinary);
     done();
   });

   receiver.write(frame);
 });

 it('parses a 300 B fragmented masked text message', (done) => {
   const receiver = new Receiver({ isServer: true });
   const msg = Buffer.from('A'.repeat(300));

   const fragment1 = msg.slice(0, 150);
   const fragment2 = msg.slice(150);

   const options = { rsv1: false, mask: true, readOnly: true };

   const frame1 = Buffer.concat(
     Sender.frame(fragment1, {
       fin: false,
       opcode: 0x01,
       ...options
     })
   );
   const frame2 = Buffer.concat(
     Sender.frame(fragment2, {
       fin: true,
       opcode: 0x00,
       ...options
     })
   );

   receiver.on('message', (data, isBinary) => {
     assert.deepStrictEqual(data, msg);
     assert.ok(!isBinary);
     done();
   });

   receiver.write(frame1);
   receiver.write(frame2);
 });

 it('parses a ping message', (done) => {
   const receiver = new Receiver({ isServer: true });
   const msg = Buffer.from('Hello');

   const list = Sender.frame(msg, {
     fin: true,
     rsv1: false,
     opcode: 0x09,
     mask: true,
     readOnly: true
   });

   const frame = Buffer.concat(list);

   receiver.on('ping', (data) => {
     assert.deepStrictEqual(data, msg);
     done();
   });

   receiver.write(frame);
 });

 it('parses a ping message with no data', (done) => {
   const receiver = new Receiver();

   receiver.on('ping', (data) => {
     assert.strictEqual(data, EMPTY_BUFFER);
     done();
   });

   receiver.write(Buffer.from('8900', 'hex'));
 });

 it('parses a 300 B fragmented masked text message with a ping in the middle (1/2)', (done) => {
   const receiver = new Receiver({ isServer: true });
   const msg = Buffer.from('A'.repeat(300));
   const pingMessage = Buffer.from('Hello');

   const fragment1 = msg.slice(0, 150);
   const fragment2 = msg.slice(150);

   const options = { rsv1: false, mask: true, readOnly: true };

   const frame1 = Buffer.concat(
     Sender.frame(fragment1, {
       fin: false,
       opcode: 0x01,
       ...options
     })
   );
   const frame2 = Buffer.concat(
     Sender.frame(pingMessage, {
       fin: true,
       opcode: 0x09,
       ...options
     })
   );
   const frame3 = Buffer.concat(
     Sender.frame(fragment2, {
       fin: true,
       opcode: 0x00,
       ...options
     })
   );

   let gotPing = false;

   receiver.on('message', (data, isBinary) => {
     assert.deepStrictEqual(data, msg);
     assert.ok(!isBinary);
     assert.ok(gotPing);
     done();
   });
   receiver.on('ping', (data) => {
     gotPing = true;
     assert.ok(data.equals(pingMessage));
   });

   receiver.write(frame1);
   receiver.write(frame2);
   receiver.write(frame3);
 });

 it('parses a 300 B fragmented masked text message with a ping in the middle (2/2)', (done) => {
   const receiver = new Receiver({ isServer: true });
   const msg = Buffer.from('A'.repeat(300));
   const pingMessage = Buffer.from('Hello');

   const fragment1 = msg.slice(0, 150);
   const fragment2 = msg.slice(150);

   const options = { rsv1: false, mask: true, readOnly: false };

   const frame1 = Buffer.concat(
     Sender.frame(Buffer.from(fragment1), {
       fin: false,
       opcode: 0x01,
       ...options
     })
   );
   const frame2 = Buffer.concat(
     Sender.frame(Buffer.from(pingMessage), {
       fin: true,
       opcode: 0x09,
       ...options
     })
   );
   const frame3 = Buffer.concat(
     Sender.frame(Buffer.from(fragment2), {
       fin: true,
       opcode: 0x00,
       ...options
     })
   );

   let chunks = [];
   const splitBuffer = (buf) => {
     const i = Math.floor(buf.length / 2);
     return [buf.slice(0, i), buf.slice(i)];
   };

   chunks = chunks.concat(splitBuffer(frame1));
   chunks = chunks.concat(splitBuffer(frame2));
   chunks = chunks.concat(splitBuffer(frame3));

   let gotPing = false;

   receiver.on('message', (data, isBinary) => {
     assert.deepStrictEqual(data, msg);
     assert.ok(!isBinary);
     assert.ok(gotPing);
     done();
   });
   receiver.on('ping', (data) => {
     gotPing = true;
     assert.ok(data.equals(pingMessage));
   });

   for (let i = 0; i < chunks.length; ++i) {
     receiver.write(chunks[i]);
   }
 });

 it('parses a 100 B masked binary message', (done) => {
   const receiver = new Receiver({ isServer: true });
   const msg = crypto.randomBytes(100);

   const list = Sender.frame(msg, {
     fin: true,
     rsv1: false,
     opcode: 0x02,
     mask: true,
     readOnly: true
   });

   const frame = Buffer.concat(list);

   receiver.on('message', (data, isBinary) => {
     assert.deepStrictEqual(data, msg);
     assert.ok(isBinary);
     done();
   });

   receiver.write(frame);
 });

 it('parses a 256 B masked binary message', (done) => {
   const receiver = new Receiver({ isServer: true });
   const msg = crypto.randomBytes(256);

   const list = Sender.frame(msg, {
     fin: true,
     rsv1: false,
     opcode: 0x02,
     mask: true,
     readOnly: true
   });

   const frame = Buffer.concat(list);

   receiver.on('message', (data, isBinary) => {
     assert.deepStrictEqual(data, msg);
     assert.ok(isBinary);
     done();
   });

   receiver.write(frame);
 });

 it('parses a 200 KiB masked binary message', (done) => {
   const receiver = new Receiver({ isServer: true });
   const msg = crypto.randomBytes(200 * 1024);

   const list = Sender.frame(msg, {
     fin: true,
     rsv1: false,
     opcode: 0x02,
     mask: true,
     readOnly: true
   });

   const frame = Buffer.concat(list);

   receiver.on('message', (data, isBinary) => {
     assert.deepStrictEqual(data, msg);
     assert.ok(isBinary);
     done();
   });

   receiver.write(frame);
 });

 it('parses a 200 KiB unmasked binary message', (done) => {
   const receiver = new Receiver();
   const msg = crypto.randomBytes(200 * 1024);

   const list = Sender.frame(msg, {
     fin: true,
     rsv1: false,
     opcode: 0x02,
     mask: false,
     readOnly: true
   });

   const frame = Buffer.concat(list);

   receiver.on('message', (data, isBinary) => {
     assert.deepStrictEqual(data, msg);
     assert.ok(isBinary);
     done();
   });

   receiver.write(frame);
 });

 it('parses a compressed message', (done) => {
   const perMessageDeflate = new PerMessageDeflate();
   perMessageDeflate.accept([{}]);

   const receiver = new Receiver({
     extensions: {
       'permessage-deflate': perMessageDeflate
     }
   });
   const buf = Buffer.from('Hello');

   receiver.on('message', (data, isBinary) => {
     assert.deepStrictEqual(data, buf);
     assert.ok(!isBinary);
     done();
   });

   perMessageDeflate.compress(buf, true, (err, data) => {
     if (err) return done(err);

     receiver.write(Buffer.from([0xc1, data.length]));
     receiver.write(data);
   });
 });

 it('parses a compressed and fragmented message', (done) => {
   const perMessageDeflate = new PerMessageDeflate();
   perMessageDeflate.accept([{}]);

   const receiver = new Receiver({
     extensions: {
       'permessage-deflate': perMessageDeflate
     }
   });
   const buf1 = Buffer.from('foo');
   const buf2 = Buffer.from('bar');

   receiver.on('message', (data, isBinary) => {
     assert.deepStrictEqual(data, Buffer.concat([buf1, buf2]));
     assert.ok(!isBinary);
     done();
   });

   perMessageDeflate.compress(buf1, false, (err, fragment1) => {
     if (err) return done(err);

     receiver.write(Buffer.from([0x41, fragment1.length]));
     receiver.write(fragment1);

     perMessageDeflate.compress(buf2, true, (err, fragment2) => {
       if (err) return done(err);

       receiver.write(Buffer.from([0x80, fragment2.length]));
       receiver.write(fragment2);
     });
   });
 });

 it('parses a buffer with thousands of frames', (done) => {
   const buf = Buffer.allocUnsafe(40000);

   for (let i = 0; i < buf.length; i += 2) {
     buf[i] = 0x81;
     buf[i + 1] = 0x00;
   }

   const receiver = new Receiver();
   let counter = 0;

   receiver.on('message', (data, isBinary) => {
     assert.strictEqual(data, EMPTY_BUFFER);
     assert.ok(!isBinary);
     if (++counter === 20000) done();
   });

   receiver.write(buf);
 });

 it('resets `totalPayloadLength` only on final frame (unfragmented)', (done) => {
   const receiver = new Receiver({ maxPayload: 10 });

   receiver.on('message', (data, isBinary) => {
     assert.strictEqual(receiver._totalPayloadLength, 0);
     assert.deepStrictEqual(data, Buffer.from('Hello'));
     assert.ok(!isBinary);
     done();
   });

   assert.strictEqual(receiver._totalPayloadLength, 0);
   receiver.write(Buffer.from('810548656c6c6f', 'hex'));
 });

 it('resets `totalPayloadLength` only on final frame (fragmented)', (done) => {
   const receiver = new Receiver({ maxPayload: 10 });

   receiver.on('message', (data, isBinary) => {
     assert.strictEqual(receiver._totalPayloadLength, 0);
     assert.deepStrictEqual(data, Buffer.from('Hello'));
     assert.ok(!isBinary);
     done();
   });

   assert.strictEqual(receiver._totalPayloadLength, 0);
   receiver.write(Buffer.from('01024865', 'hex'));
   assert.strictEqual(receiver._totalPayloadLength, 2);
   receiver.write(Buffer.from('80036c6c6f', 'hex'));
 });

 it('resets `totalPayloadLength` only on final frame (fragmented + ping)', (done) => {
   const receiver = new Receiver({ maxPayload: 10 });
   let data;

   receiver.on('ping', (buf) => {
     assert.strictEqual(receiver._totalPayloadLength, 2);
     data = buf;
   });
   receiver.on('message', (buf, isBinary) => {
     assert.strictEqual(receiver._totalPayloadLength, 0);
     assert.deepStrictEqual(data, EMPTY_BUFFER);
     assert.deepStrictEqual(buf, Buffer.from('Hello'));
     assert.ok(isBinary);
     done();
   });

   assert.strictEqual(receiver._totalPayloadLength, 0);
   receiver.write(Buffer.from('02024865', 'hex'));
   receiver.write(Buffer.from('8900', 'hex'));
   receiver.write(Buffer.from('80036c6c6f', 'hex'));
 });

 it('ignores any data after a close frame', (done) => {
   const perMessageDeflate = new PerMessageDeflate();
   perMessageDeflate.accept([{}]);

   const receiver = new Receiver({
     extensions: {
       'permessage-deflate': perMessageDeflate
     }
   });
   const results = [];
   const push = results.push.bind(results);

   receiver.on('conclude', push).on('message', push);
   receiver.on('finish', () => {
     assert.deepStrictEqual(results, [
       EMPTY_BUFFER,
       false,
       1005,
       EMPTY_BUFFER
     ]);
     done();
   });

   receiver.write(Buffer.from([0xc1, 0x01, 0x00]));
   receiver.write(Buffer.from([0x88, 0x00]));
   receiver.write(Buffer.from([0x81, 0x00]));
 });

 it('emits an error if RSV1 is on and permessage-deflate is disabled', (done) => {
   const receiver = new 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'
     );
     assert.strictEqual(err[kStatusCode], 1002);
     done();
   });

   receiver.write(Buffer.from([0xc2, 0x80, 0x00, 0x00, 0x00, 0x00]));
 });

 it('emits an error if RSV1 is on and opcode is 0', (done) => {
   const perMessageDeflate = new PerMessageDeflate();
   perMessageDeflate.accept([{}]);

   const receiver = new Receiver({
     extensions: {
       'permessage-deflate': perMessageDeflate
     }
   });

   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'
     );
     assert.strictEqual(err[kStatusCode], 1002);
     done();
   });

   receiver.write(Buffer.from([0x40, 0x00]));
 });

 it('emits an error if RSV2 is on', (done) => {
   const receiver = new 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'
     );
     assert.strictEqual(err[kStatusCode], 1002);
     done();
   });

   receiver.write(Buffer.from([0xa2, 0x00]));
 });

 it('emits an error if RSV3 is on', (done) => {
   const receiver = new 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'
     );
     assert.strictEqual(err[kStatusCode], 1002);
     done();
   });

   receiver.write(Buffer.from([0x92, 0x00]));
 });

 it('emits an error if the first frame in a fragmented message has opcode 0', (done) => {
   const receiver = new 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'
     );
     assert.strictEqual(err[kStatusCode], 1002);
     done();
   });

   receiver.write(Buffer.from([0x00, 0x00]));
 });

 it('emits an error if a frame has opcode 1 in the middle of a fragmented message', (done) => {
   const receiver = new 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'
     );
     assert.strictEqual(err[kStatusCode], 1002);
     done();
   });

   receiver.write(Buffer.from([0x01, 0x00]));
   receiver.write(Buffer.from([0x01, 0x00]));
 });

 it('emits an error if a frame has opcode 2 in the middle of a fragmented message', (done) => {
   const receiver = new 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'
     );
     assert.strictEqual(err[kStatusCode], 1002);
     done();
   });

   receiver.write(Buffer.from([0x01, 0x00]));
   receiver.write(Buffer.from([0x02, 0x00]));
 });

 it('emits an error if a control frame has the FIN bit off', (done) => {
   const receiver = new 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'
     );
     assert.strictEqual(err[kStatusCode], 1002);
     done();
   });

   receiver.write(Buffer.from([0x09, 0x00]));
 });

 it('emits an error if a control frame has the RSV1 bit on', (done) => {
   const perMessageDeflate = new PerMessageDeflate();
   perMessageDeflate.accept([{}]);

   const receiver = new Receiver({
     extensions: {
       'permessage-deflate': perMessageDeflate
     }
   });

   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'
     );
     assert.strictEqual(err[kStatusCode], 1002);
     done();
   });

   receiver.write(Buffer.from([0xc9, 0x00]));
 });

 it('emits an error if a control frame has the FIN bit off', (done) => {
   const receiver = new 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'
     );
     assert.strictEqual(err[kStatusCode], 1002);
     done();
   });

   receiver.write(Buffer.from([0x09, 0x00]));
 });

 it('emits an error if a frame has the MASK bit off (server mode)', (done) => {
   const receiver = new Receiver({ isServer: true });

   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'
     );
     assert.strictEqual(err[kStatusCode], 1002);
     done();
   });

   receiver.write(Buffer.from([0x81, 0x02, 0x68, 0x69]));
 });

 it('emits an error if a frame has the MASK bit on (client mode)', (done) => {
   const receiver = new 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'
     );
     assert.strictEqual(err[kStatusCode], 1002);
     done();
   });

   receiver.write(
     Buffer.from([0x81, 0x82, 0x56, 0x3a, 0xac, 0x80, 0x3e, 0x53])
   );
 });

 it('emits an error if a control frame has a payload bigger than 125 B', (done) => {
   const receiver = new 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'
     );
     assert.strictEqual(err[kStatusCode], 1002);
     done();
   });

   receiver.write(Buffer.from([0x89, 0x7e]));
 });

 it('emits an error if a data frame has a payload bigger than 2^53 - 1 B', (done) => {
   const receiver = new Receiver();

   receiver.on('error', (err) => {
     assert.ok(err instanceof RangeError);
     assert.strictEqual(err.code, 'WS_ERR_UNSUPPORTED_DATA_PAYLOAD_LENGTH');
     assert.strictEqual(
       err.message,
       'Unsupported WebSocket frame: payload length > 2^53 - 1'
     );
     assert.strictEqual(err[kStatusCode], 1009);
     done();
   });

   receiver.write(Buffer.from([0x82, 0x7f]));
   setImmediate(() =>
     receiver.write(
       Buffer.from([0x00, 0x20, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00])
     )
   );
 });

 it('emits an error if a text frame contains invalid UTF-8 data (1/2)', (done) => {
   const receiver = new 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'
     );
     assert.strictEqual(err[kStatusCode], 1007);
     done();
   });

   receiver.write(Buffer.from([0x81, 0x04, 0xce, 0xba, 0xe1, 0xbd]));
 });

 it('emits an error if a text frame contains invalid UTF-8 data (2/2)', (done) => {
   const perMessageDeflate = new PerMessageDeflate();
   perMessageDeflate.accept([{}]);

   const receiver = new Receiver({
     extensions: {
       'permessage-deflate': perMessageDeflate
     }
   });
   const buf = Buffer.from([0xce, 0xba, 0xe1, 0xbd]);

   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'
     );
     assert.strictEqual(err[kStatusCode], 1007);
     done();
   });

   perMessageDeflate.compress(buf, true, (err, data) => {
     if (err) return done(err);

     receiver.write(Buffer.from([0xc1, data.length]));
     receiver.write(data);
   });
 });

 it('emits an error if a close frame has a payload of 1 B', (done) => {
   const receiver = new 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'
     );
     assert.strictEqual(err[kStatusCode], 1002);
     done();
   });

   receiver.write(Buffer.from([0x88, 0x01, 0x00]));
 });

 it('emits an error if a close frame contains an invalid close code', (done) => {
   const receiver = new 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'
     );
     assert.strictEqual(err[kStatusCode], 1002);
     done();
   });

   receiver.write(Buffer.from([0x88, 0x02, 0x00, 0x00]));
 });

 it('emits an error if a close frame contains invalid UTF-8 data', (done) => {
   const receiver = new 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'
     );
     assert.strictEqual(err[kStatusCode], 1007);
     done();
   });

   receiver.write(
     Buffer.from([0x88, 0x06, 0x03, 0xef, 0xce, 0xba, 0xe1, 0xbd])
   );
 });

 it('emits an error if a frame payload length is bigger than `maxPayload`', (done) => {
   const receiver = new Receiver({ isServer: true, maxPayload: 20 * 1024 });
   const msg = crypto.randomBytes(200 * 1024);

   const list = Sender.frame(msg, {
     fin: true,
     rsv1: false,
     opcode: 0x02,
     mask: true,
     readOnly: true
   });

   const frame = Buffer.concat(list);

   receiver.on('error', (err) => {
     assert.ok(err instanceof RangeError);
     assert.strictEqual(err.code, 'WS_ERR_UNSUPPORTED_MESSAGE_LENGTH');
     assert.strictEqual(err.message, 'Max payload size exceeded');
     assert.strictEqual(err[kStatusCode], 1009);
     done();
   });

   receiver.write(frame);
 });

 it('emits an error if the message length exceeds `maxPayload`', (done) => {
   const perMessageDeflate = new PerMessageDeflate({}, false, 25);
   perMessageDeflate.accept([{}]);

   const receiver = new Receiver({
     extensions: { 'permessage-deflate': perMessageDeflate },
     isServer: false,
     maxPayload: 25
   });
   const buf = Buffer.from('A'.repeat(50));

   receiver.on('error', (err) => {
     assert.ok(err instanceof RangeError);
     assert.strictEqual(err.code, 'WS_ERR_UNSUPPORTED_MESSAGE_LENGTH');
     assert.strictEqual(err.message, 'Max payload size exceeded');
     assert.strictEqual(err[kStatusCode], 1009);
     done();
   });

   perMessageDeflate.compress(buf, true, (err, data) => {
     if (err) return done(err);

     receiver.write(Buffer.from([0xc1, data.length]));
     receiver.write(data);
   });
 });

 it('emits an error if the sum of fragment lengths exceeds `maxPayload`', (done) => {
   const perMessageDeflate = new PerMessageDeflate({}, false, 25);
   perMessageDeflate.accept([{}]);

   const receiver = new Receiver({
     extensions: { 'permessage-deflate': perMessageDeflate },
     isServer: false,
     maxPayload: 25
   });
   const buf = Buffer.from('A'.repeat(15));

   receiver.on('error', (err) => {
     assert.ok(err instanceof RangeError);
     assert.strictEqual(err.code, 'WS_ERR_UNSUPPORTED_MESSAGE_LENGTH');
     assert.strictEqual(err.message, 'Max payload size exceeded');
     assert.strictEqual(err[kStatusCode], 1009);
     done();
   });

   perMessageDeflate.compress(buf, false, (err, fragment1) => {
     if (err) return done(err);

     receiver.write(Buffer.from([0x41, fragment1.length]));
     receiver.write(fragment1);

     perMessageDeflate.compress(buf, true, (err, fragment2) => {
       if (err) return done(err);

       receiver.write(Buffer.from([0x80, fragment2.length]));
       receiver.write(fragment2);
     });
   });
 });

 it("honors the 'nodebuffer' binary type", (done) => {
   const receiver = new Receiver();
   const frags = [
     crypto.randomBytes(7321),
     crypto.randomBytes(137),
     crypto.randomBytes(285787),
     crypto.randomBytes(3)
   ];

   receiver.on('message', (data, isBinary) => {
     assert.deepStrictEqual(data, Buffer.concat(frags));
     assert.ok(isBinary);
     done();
   });

   frags.forEach((frag, i) => {
     Sender.frame(frag, {
       fin: i === frags.length - 1,
       opcode: i === 0 ? 2 : 0,
       readOnly: true,
       mask: false,
       rsv1: false
     }).forEach((buf) => receiver.write(buf));
   });
 });

 it("honors the 'arraybuffer' binary type", (done) => {
   const receiver = new Receiver({ binaryType: 'arraybuffer' });
   const frags = [
     crypto.randomBytes(19221),
     crypto.randomBytes(954),
     crypto.randomBytes(623987)
   ];

   receiver.on('message', (data, isBinary) => {
     assert.ok(data instanceof ArrayBuffer);
     assert.deepStrictEqual(Buffer.from(data), Buffer.concat(frags));
     assert.ok(isBinary);
     done();
   });

   frags.forEach((frag, i) => {
     Sender.frame(frag, {
       fin: i === frags.length - 1,
       opcode: i === 0 ? 2 : 0,
       readOnly: true,
       mask: false,
       rsv1: false
     }).forEach((buf) => receiver.write(buf));
   });
 });

 it("honors the 'fragments' binary type", (done) => {
   const receiver = new Receiver({ binaryType: 'fragments' });
   const frags = [
     crypto.randomBytes(17),
     crypto.randomBytes(419872),
     crypto.randomBytes(83),
     crypto.randomBytes(9928),
     crypto.randomBytes(1)
   ];

   receiver.on('message', (data, isBinary) => {
     assert.deepStrictEqual(data, frags);
     assert.ok(isBinary);
     done();
   });

   frags.forEach((frag, i) => {
     Sender.frame(frag, {
       fin: i === frags.length - 1,
       opcode: i === 0 ? 2 : 0,
       readOnly: true,
       mask: false,
       rsv1: false
     }).forEach((buf) => receiver.write(buf));
   });
 });

 it('honors the `skipUTF8Validation` option (1/2)', (done) => {
   const receiver = new Receiver({ skipUTF8Validation: true });

   receiver.on('message', (data, isBinary) => {
     assert.deepStrictEqual(data, Buffer.from([0xf8]));
     assert.ok(!isBinary);
     done();
   });

   receiver.write(Buffer.from([0x81, 0x01, 0xf8]));
 });

 it('honors the `skipUTF8Validation` option (2/2)', (done) => {
   const receiver = new Receiver({ skipUTF8Validation: true });

   receiver.on('conclude', (code, data) => {
     assert.strictEqual(code, 1000);
     assert.deepStrictEqual(data, Buffer.from([0xf8]));
     done();
   });

   receiver.write(Buffer.from([0x88, 0x03, 0x03, 0xe8, 0xf8]));
 });
});