1 | 'use strict';
|
2 |
|
3 | const EventEmitter = require('events');
|
4 | const crypto = require('crypto');
|
5 | const http = require('http');
|
6 | const url = require('url');
|
7 |
|
8 | const PerMessageDeflate = require('./permessage-deflate');
|
9 | const extension = require('./extension');
|
10 | const constants = require('./constants');
|
11 | const WebSocket = require('./websocket');
|
12 |
|
13 |
|
14 |
|
15 |
|
16 |
|
17 |
|
18 | class WebSocketServer extends EventEmitter {
|
19 | |
20 |
|
21 |
|
22 |
|
23 |
|
24 |
|
25 |
|
26 |
|
27 |
|
28 |
|
29 |
|
30 |
|
31 |
|
32 |
|
33 |
|
34 |
|
35 | constructor (options, callback) {
|
36 | super();
|
37 |
|
38 | options = Object.assign({
|
39 | maxPayload: 100 * 1024 * 1024,
|
40 | perMessageDeflate: false,
|
41 | handleProtocols: null,
|
42 | clientTracking: true,
|
43 | verifyClient: null,
|
44 | noServer: false,
|
45 | backlog: null,
|
46 | server: null,
|
47 | host: null,
|
48 | path: null,
|
49 | port: null
|
50 | }, options);
|
51 |
|
52 | if (options.port == null && !options.server && !options.noServer) {
|
53 | throw new TypeError(
|
54 | 'One of the "port", "server", or "noServer" options must be specified'
|
55 | );
|
56 | }
|
57 |
|
58 | if (options.port != null) {
|
59 | this._server = http.createServer((req, res) => {
|
60 | const body = http.STATUS_CODES[426];
|
61 |
|
62 | res.writeHead(426, {
|
63 | 'Content-Length': body.length,
|
64 | 'Content-Type': 'text/plain'
|
65 | });
|
66 | res.end(body);
|
67 | });
|
68 | this._server.listen(options.port, options.host, options.backlog, callback);
|
69 | } else if (options.server) {
|
70 | this._server = options.server;
|
71 | }
|
72 |
|
73 | if (this._server) {
|
74 | this._removeListeners = addListeners(this._server, {
|
75 | listening: this.emit.bind(this, 'listening'),
|
76 | error: this.emit.bind(this, 'error'),
|
77 | upgrade: (req, socket, head) => {
|
78 | this.handleUpgrade(req, socket, head, (ws) => {
|
79 | this.emit('connection', ws, req);
|
80 | });
|
81 | }
|
82 | });
|
83 | }
|
84 |
|
85 | if (options.perMessageDeflate === true) options.perMessageDeflate = {};
|
86 | if (options.clientTracking) this.clients = new Set();
|
87 | this.options = options;
|
88 | }
|
89 |
|
90 | |
91 |
|
92 |
|
93 |
|
94 |
|
95 |
|
96 |
|
97 |
|
98 |
|
99 | address () {
|
100 | if (this.options.noServer) {
|
101 | throw new Error('The server is operating in "noServer" mode');
|
102 | }
|
103 |
|
104 | if (!this._server) return null;
|
105 | return this._server.address();
|
106 | }
|
107 |
|
108 | |
109 |
|
110 |
|
111 |
|
112 |
|
113 |
|
114 | close (cb) {
|
115 |
|
116 |
|
117 |
|
118 | if (this.clients) {
|
119 | for (const client of this.clients) client.terminate();
|
120 | }
|
121 |
|
122 | const server = this._server;
|
123 |
|
124 | if (server) {
|
125 | this._removeListeners();
|
126 | this._removeListeners = this._server = null;
|
127 |
|
128 |
|
129 |
|
130 |
|
131 | if (this.options.port != null) return server.close(cb);
|
132 | }
|
133 |
|
134 | if (cb) cb();
|
135 | }
|
136 |
|
137 | |
138 |
|
139 |
|
140 |
|
141 |
|
142 |
|
143 |
|
144 | shouldHandle (req) {
|
145 | if (this.options.path && url.parse(req.url).pathname !== this.options.path) {
|
146 | return false;
|
147 | }
|
148 |
|
149 | return true;
|
150 | }
|
151 |
|
152 | |
153 |
|
154 |
|
155 |
|
156 |
|
157 |
|
158 |
|
159 |
|
160 |
|
161 | handleUpgrade (req, socket, head, cb) {
|
162 | socket.on('error', socketOnError);
|
163 |
|
164 | const version = +req.headers['sec-websocket-version'];
|
165 | const extensions = {};
|
166 |
|
167 | if (
|
168 | req.method !== 'GET' || req.headers.upgrade.toLowerCase() !== 'websocket' ||
|
169 | !req.headers['sec-websocket-key'] || (version !== 8 && version !== 13) ||
|
170 | !this.shouldHandle(req)
|
171 | ) {
|
172 | return abortHandshake(socket, 400);
|
173 | }
|
174 |
|
175 | if (this.options.perMessageDeflate) {
|
176 | const perMessageDeflate = new PerMessageDeflate(
|
177 | this.options.perMessageDeflate,
|
178 | true,
|
179 | this.options.maxPayload
|
180 | );
|
181 |
|
182 | try {
|
183 | const offers = extension.parse(
|
184 | req.headers['sec-websocket-extensions']
|
185 | );
|
186 |
|
187 | if (offers[PerMessageDeflate.extensionName]) {
|
188 | perMessageDeflate.accept(offers[PerMessageDeflate.extensionName]);
|
189 | extensions[PerMessageDeflate.extensionName] = perMessageDeflate;
|
190 | }
|
191 | } catch (err) {
|
192 | return abortHandshake(socket, 400);
|
193 | }
|
194 | }
|
195 |
|
196 |
|
197 |
|
198 |
|
199 | if (this.options.verifyClient) {
|
200 | const info = {
|
201 | origin: req.headers[`${version === 8 ? 'sec-websocket-origin' : 'origin'}`],
|
202 | secure: !!(req.connection.authorized || req.connection.encrypted),
|
203 | req
|
204 | };
|
205 |
|
206 | if (this.options.verifyClient.length === 2) {
|
207 | this.options.verifyClient(info, (verified, code, message, headers) => {
|
208 | if (!verified) {
|
209 | return abortHandshake(socket, code || 401, message, headers);
|
210 | }
|
211 |
|
212 | this.completeUpgrade(extensions, req, socket, head, cb);
|
213 | });
|
214 | return;
|
215 | }
|
216 |
|
217 | if (!this.options.verifyClient(info)) return abortHandshake(socket, 401);
|
218 | }
|
219 |
|
220 | this.completeUpgrade(extensions, req, socket, head, cb);
|
221 | }
|
222 |
|
223 | |
224 |
|
225 |
|
226 |
|
227 |
|
228 |
|
229 |
|
230 |
|
231 |
|
232 |
|
233 | completeUpgrade (extensions, req, socket, head, cb) {
|
234 |
|
235 |
|
236 |
|
237 | if (!socket.readable || !socket.writable) return socket.destroy();
|
238 |
|
239 | const key = crypto.createHash('sha1')
|
240 | .update(req.headers['sec-websocket-key'] + constants.GUID, 'binary')
|
241 | .digest('base64');
|
242 |
|
243 | const headers = [
|
244 | 'HTTP/1.1 101 Switching Protocols',
|
245 | 'Upgrade: websocket',
|
246 | 'Connection: Upgrade',
|
247 | `Sec-WebSocket-Accept: ${key}`
|
248 | ];
|
249 |
|
250 | const ws = new WebSocket(null);
|
251 | var protocol = req.headers['sec-websocket-protocol'];
|
252 |
|
253 | if (protocol) {
|
254 | protocol = protocol.trim().split(/ *, */);
|
255 |
|
256 |
|
257 |
|
258 |
|
259 | if (this.options.handleProtocols) {
|
260 | protocol = this.options.handleProtocols(protocol, req);
|
261 | } else {
|
262 | protocol = protocol[0];
|
263 | }
|
264 |
|
265 | if (protocol) {
|
266 | headers.push(`Sec-WebSocket-Protocol: ${protocol}`);
|
267 | ws.protocol = protocol;
|
268 | }
|
269 | }
|
270 |
|
271 | if (extensions[PerMessageDeflate.extensionName]) {
|
272 | const params = extensions[PerMessageDeflate.extensionName].params;
|
273 | const value = extension.format({
|
274 | [PerMessageDeflate.extensionName]: [params]
|
275 | });
|
276 | headers.push(`Sec-WebSocket-Extensions: ${value}`);
|
277 | ws._extensions = extensions;
|
278 | }
|
279 |
|
280 |
|
281 |
|
282 |
|
283 | this.emit('headers', headers, req);
|
284 |
|
285 | socket.write(headers.concat('\r\n').join('\r\n'));
|
286 | socket.removeListener('error', socketOnError);
|
287 |
|
288 | ws.setSocket(socket, head, this.options.maxPayload);
|
289 |
|
290 | if (this.clients) {
|
291 | this.clients.add(ws);
|
292 | ws.on('close', () => this.clients.delete(ws));
|
293 | }
|
294 |
|
295 | cb(ws);
|
296 | }
|
297 | }
|
298 |
|
299 | module.exports = WebSocketServer;
|
300 |
|
301 |
|
302 |
|
303 |
|
304 |
|
305 |
|
306 |
|
307 |
|
308 |
|
309 |
|
310 | function addListeners (server, map) {
|
311 | for (const event of Object.keys(map)) server.on(event, map[event]);
|
312 |
|
313 | return function removeListeners () {
|
314 | for (const event of Object.keys(map)) {
|
315 | server.removeListener(event, map[event]);
|
316 | }
|
317 | };
|
318 | }
|
319 |
|
320 |
|
321 |
|
322 |
|
323 |
|
324 |
|
325 | function socketOnError () {
|
326 | this.destroy();
|
327 | }
|
328 |
|
329 |
|
330 |
|
331 |
|
332 |
|
333 |
|
334 |
|
335 |
|
336 |
|
337 |
|
338 | function abortHandshake (socket, code, message, headers) {
|
339 | if (socket.writable) {
|
340 | message = message || http.STATUS_CODES[code];
|
341 | headers = Object.assign({
|
342 | 'Connection': 'close',
|
343 | 'Content-type': 'text/html',
|
344 | 'Content-Length': Buffer.byteLength(message)
|
345 | }, headers);
|
346 |
|
347 | socket.write(
|
348 | `HTTP/1.1 ${code} ${http.STATUS_CODES[code]}\r\n` +
|
349 | Object.keys(headers).map(h => `${h}: ${headers[h]}`).join('\r\n') +
|
350 | '\r\n\r\n' +
|
351 | message
|
352 | );
|
353 | }
|
354 |
|
355 | socket.removeListener('error', socketOnError);
|
356 | socket.destroy();
|
357 | }
|