3 var crypto = require('crypto'),
4 util = require('util'),
5 Extensions = require('websocket-extensions'),
6 Base = require('./base'),
7 Frame = require('./hybi/frame'),
8 Message = require('./hybi/message');
10 var Hybi = function(request, url, options) {
11 Base.apply(this, arguments);
13 this._extensions = new Extensions();
15 this._masking = this._options.masking;
16 this._protocols = this._options.protocols || [];
17 this._requireMasking = this._options.requireMasking;
18 this._pingCallbacks = {};
20 if (typeof this._protocols === 'string')
21 this._protocols = this._protocols.split(/ *, */);
23 if (!this._request) return;
25 var secKey = this._request.headers['sec-websocket-key'],
26 protos = this._request.headers['sec-websocket-protocol'],
27 version = this._request.headers['sec-websocket-version'],
28 supported = this._protocols;
30 this._headers.set('Upgrade', 'websocket');
31 this._headers.set('Connection', 'Upgrade');
32 this._headers.set('Sec-WebSocket-Accept', Hybi.generateAccept(secKey));
34 if (protos !== undefined) {
35 if (typeof protos === 'string') protos = protos.split(/ *, */);
36 this.protocol = protos.filter(function(p) { return supported.indexOf(p) >= 0 })[0];
37 if (this.protocol) this._headers.set('Sec-WebSocket-Protocol', this.protocol);
40 this.version = 'hybi-' + version;
42 util.inherits(Hybi, Base);
44 Hybi.mask = function(payload, mask, offset) {
45 if (!mask || mask.length === 0) return payload;
48 for (var i = 0, n = payload.length - offset; i < n; i++) {
49 payload[offset + i] = payload[offset + i] ^ mask[i % 4];
54 Hybi.generateAccept = function(key) {
55 var sha1 = crypto.createHash('sha1');
56 sha1.update(key + Hybi.GUID);
57 return sha1.digest('base64');
60 Hybi.GUID = '258EAFA5-E914-47DA-95CA-C5AB0DC85B11';
80 OPCODE_CODES: [0, 1, 2, 8, 9, 10],
81 MESSAGE_OPCODES: [0, 1, 2],
82 OPENING_OPCODES: [1, 2],
90 policy_violation: 1008,
92 extension_error: 1010,
93 unexpected_condition: 1011
96 ERROR_CODES: [1000, 1001, 1002, 1003, 1007, 1008, 1009, 1010, 1011],
97 DEFAULT_ERROR_CODE: 1000,
98 MIN_RESERVED_ERROR: 3000,
99 MAX_RESERVED_ERROR: 4999,
101 // http://www.w3.org/International/questions/qa-forms-utf-8.en.php
102 UTF8_MATCH: /^([\x00-\x7F]|[\xC2-\xDF][\x80-\xBF]|\xE0[\xA0-\xBF][\x80-\xBF]|[\xE1-\xEC\xEE\xEF][\x80-\xBF]{2}|\xED[\x80-\x9F][\x80-\xBF]|\xF0[\x90-\xBF][\x80-\xBF]{2}|[\xF1-\xF3][\x80-\xBF]{3}|\xF4[\x80-\x8F][\x80-\xBF]{2})*$/,
104 addExtension: function(extension) {
105 this._extensions.add(extension);
109 parse: function(chunk) {
110 this._reader.put(chunk);
113 switch (this._stage) {
115 buffer = this._reader.read(1);
116 if (buffer) this._parseOpcode(buffer[0]);
120 buffer = this._reader.read(1);
121 if (buffer) this._parseLength(buffer[0]);
125 buffer = this._reader.read(this._frame.lengthBytes);
126 if (buffer) this._parseExtendedLength(buffer);
130 buffer = this._reader.read(4);
133 this._frame.maskingKey = buffer;
138 buffer = this._reader.read(this._frame.length);
141 this._emitFrame(buffer);
151 text: function(message) {
152 if (this.readyState > 1) return false;
153 return this.frame(message, 'text');
156 binary: function(message) {
157 if (this.readyState > 1) return false;
158 return this.frame(message, 'binary');
161 ping: function(message, callback) {
162 if (this.readyState > 1) return false;
163 message = message || '';
164 if (callback) this._pingCallbacks[message] = callback;
165 return this.frame(message, 'ping');
168 pong: function(message) {
169 if (this.readyState > 1) return false;
170 message = message ||'';
171 return this.frame(message, 'pong');
174 close: function(reason, code) {
175 reason = reason || '';
176 code = code || this.ERRORS.normal_closure;
178 if (this.readyState <= 0) {
180 this.emit('close', new Base.CloseEvent(code, reason));
182 } else if (this.readyState === 1) {
184 this._extensions.close(function() { this.frame(reason, 'close', code) }, this);
191 frame: function(buffer, type, code) {
192 if (this.readyState <= 0) return this._queue([buffer, type, code]);
193 if (this.readyState > 2) return false;
195 if (buffer instanceof Array) buffer = new Buffer(buffer);
196 if (typeof buffer === 'number') buffer = buffer.toString();
198 var message = new Message(),
199 isText = (typeof buffer === 'string'),
202 message.rsv1 = message.rsv2 = message.rsv3 = false;
203 message.opcode = this.OPCODES[type || (isText ? 'text' : 'binary')];
205 payload = isText ? new Buffer(buffer, 'utf8') : buffer;
209 payload = new Buffer(2 + copy.length);
210 payload.writeUInt16BE(code, 0);
211 copy.copy(payload, 2);
213 message.data = payload;
215 var onMessageReady = function(message) {
216 var frame = new Frame();
219 frame.rsv1 = message.rsv1;
220 frame.rsv2 = message.rsv2;
221 frame.rsv3 = message.rsv3;
222 frame.opcode = message.opcode;
223 frame.masked = !!this._masking;
224 frame.length = message.data.length;
225 frame.payload = message.data;
227 if (frame.masked) frame.maskingKey = crypto.randomBytes(4);
229 this._sendFrame(frame);
232 if (this.MESSAGE_OPCODES.indexOf(message.opcode) >= 0)
233 this._extensions.processOutgoingMessage(message, function(error, message) {
234 if (error) return this._fail('extension_error', error.message);
235 onMessageReady.call(this, message);
238 onMessageReady.call(this, message);
243 _sendFrame: function(frame) {
244 var length = frame.length,
245 header = (length <= 125) ? 2 : (length <= 65535 ? 4 : 10),
246 offset = header + (frame.masked ? 4 : 0),
247 buffer = new Buffer(offset + length),
248 masked = frame.masked ? this.MASK : 0;
250 buffer[0] = (frame.final ? this.FIN : 0) |
251 (frame.rsv1 ? this.RSV1 : 0) |
252 (frame.rsv2 ? this.RSV2 : 0) |
253 (frame.rsv3 ? this.RSV3 : 0) |
257 buffer[1] = masked | length;
258 } else if (length <= 65535) {
259 buffer[1] = masked | 126;
260 buffer.writeUInt16BE(length, 2);
262 buffer[1] = masked | 127;
263 buffer.writeUInt32BE(Math.floor(length / 0x100000000), 2);
264 buffer.writeUInt32BE(length % 0x100000000, 6);
267 frame.payload.copy(buffer, offset);
270 frame.maskingKey.copy(buffer, header);
271 Hybi.mask(buffer, frame.maskingKey, offset);
277 _handshakeResponse: function() {
279 var extensions = this._extensions.generateResponse(this._request.headers['sec-websocket-extensions']);
281 return this._fail('protocol_error', e.message);
284 if (extensions) this._headers.set('Sec-WebSocket-Extensions', extensions);
286 var start = 'HTTP/1.1 101 Switching Protocols',
287 headers = [start, this._headers.toString(), ''];
289 return new Buffer(headers.join('\r\n'), 'utf8');
292 _shutdown: function(code, reason, error) {
294 delete this._message;
297 var sendCloseFrame = (this.readyState === 1);
300 this._extensions.close(function() {
301 if (sendCloseFrame) this.frame(reason, 'close', code);
303 if (error) this.emit('error', new Error(reason));
304 this.emit('close', new Base.CloseEvent(code, reason));
308 _fail: function(type, message) {
309 if (this.readyState > 1) return;
310 this._shutdown(this.ERRORS[type], message, true);
313 _parseOpcode: function(octet) {
314 var rsvs = [this.RSV1, this.RSV2, this.RSV3].map(function(rsv) {
315 return (octet & rsv) === rsv;
318 var frame = this._frame = new Frame();
320 frame.final = (octet & this.FIN) === this.FIN;
321 frame.rsv1 = rsvs[0];
322 frame.rsv2 = rsvs[1];
323 frame.rsv3 = rsvs[2];
324 frame.opcode = (octet & this.OPCODE);
328 if (!this._extensions.validFrameRsv(frame))
329 return this._fail('protocol_error',
330 'One or more reserved bits are on: reserved1 = ' + (frame.rsv1 ? 1 : 0) +
331 ', reserved2 = ' + (frame.rsv2 ? 1 : 0) +
332 ', reserved3 = ' + (frame.rsv3 ? 1 : 0));
334 if (this.OPCODE_CODES.indexOf(frame.opcode) < 0)
335 return this._fail('protocol_error', 'Unrecognized frame opcode: ' + frame.opcode);
337 if (this.MESSAGE_OPCODES.indexOf(frame.opcode) < 0 && !frame.final)
338 return this._fail('protocol_error', 'Received fragmented control frame: opcode = ' + frame.opcode);
340 if (this._message && this.OPENING_OPCODES.indexOf(frame.opcode) >= 0)
341 return this._fail('protocol_error', 'Received new data frame but previous continuous frame is unfinished');
344 _parseLength: function(octet) {
345 var frame = this._frame;
346 frame.masked = (octet & this.MASK) === this.MASK;
347 frame.length = (octet & this.LENGTH);
349 if (frame.length >= 0 && frame.length <= 125) {
350 this._stage = frame.masked ? 3 : 4;
351 if (!this._checkFrameLength()) return;
354 frame.lengthBytes = (frame.length === 126 ? 2 : 8);
357 if (this._requireMasking && !frame.masked)
358 return this._fail('unacceptable', 'Received unmasked frame but masking is required');
361 _parseExtendedLength: function(buffer) {
362 var frame = this._frame;
363 frame.length = this._readUInt(buffer);
365 this._stage = frame.masked ? 3 : 4;
367 if (this.MESSAGE_OPCODES.indexOf(frame.opcode) < 0 && frame.length > 125)
368 return this._fail('protocol_error', 'Received control frame having too long payload: ' + frame.length);
370 if (!this._checkFrameLength()) return;
373 _checkFrameLength: function() {
374 var length = this._message ? this._message.length : 0;
376 if (length + this._frame.length > this._maxLength) {
377 this._fail('too_large', 'WebSocket frame length too large');
384 _emitFrame: function(buffer) {
385 var frame = this._frame,
386 payload = frame.payload = Hybi.mask(buffer, frame.maskingKey),
387 opcode = frame.opcode,
394 if (opcode === this.OPCODES.continuation) {
395 if (!this._message) return this._fail('protocol_error', 'Received unexpected continuation frame');
396 this._message.pushFrame(frame);
399 if (opcode === this.OPCODES.text || opcode === this.OPCODES.binary) {
400 this._message = new Message();
401 this._message.pushFrame(frame);
404 if (frame.final && this.MESSAGE_OPCODES.indexOf(opcode) >= 0)
405 return this._emitMessage(this._message);
407 if (opcode === this.OPCODES.close) {
408 code = (payload.length >= 2) ? payload.readUInt16BE(0) : null;
409 reason = (payload.length > 2) ? this._encode(payload.slice(2)) : null;
411 if (!(payload.length === 0) &&
412 !(code !== null && code >= this.MIN_RESERVED_ERROR && code <= this.MAX_RESERVED_ERROR) &&
413 this.ERROR_CODES.indexOf(code) < 0)
414 code = this.ERRORS.protocol_error;
416 if (payload.length > 125 || (payload.length > 2 && !reason))
417 code = this.ERRORS.protocol_error;
419 this._shutdown(code || this.DEFAULT_ERROR_CODE, reason || '');
422 if (opcode === this.OPCODES.ping) {
423 this.frame(payload, 'pong');
426 if (opcode === this.OPCODES.pong) {
427 callbacks = this._pingCallbacks;
428 message = this._encode(payload);
429 callback = callbacks[message];
431 delete callbacks[message];
432 if (callback) callback()
436 _emitMessage: function(message) {
437 var message = this._message;
440 delete this._message;
442 this._extensions.processIncomingMessage(message, function(error, message) {
443 if (error) return this._fail('extension_error', error.message);
445 var payload = message.data;
446 if (message.opcode === this.OPCODES.text) payload = this._encode(payload);
448 if (payload === null)
449 return this._fail('encoding_error', 'Could not decode a text frame as UTF-8');
451 this.emit('message', new Base.MessageEvent(payload));
455 _encode: function(buffer) {
457 var string = buffer.toString('binary', 0, buffer.length);
458 if (!this.UTF8_MATCH.test(string)) return null;
460 return buffer.toString('utf8', 0, buffer.length);
463 _readUInt: function(buffer) {
464 if (buffer.length === 2) return buffer.readUInt16BE(0);
466 return buffer.readUInt32BE(0) * 0x100000000 +
467 buffer.readUInt32BE(4);
471 for (var key in instance)
472 Hybi.prototype[key] = instance[key];
474 module.exports = Hybi;