basic handshake handling

2021-01-26 12:04:53 +02:00 · 2021-01-26 12:04:53 +02:00 · 641a978cbe
commit 641a978cbe
parent ac6cdf7bc9
7 changed files with 139 additions and 0 deletions
--- a/example/example.html
+++ b/example/example.html
@ -0,0 +1,28 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+    <meta charset="UTF-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <title>Wormhole test</title>
+
+    <script>
+        // Create WebSocket connection.
+        const socket = new WebSocket('ws://localhost:8080/hello');
+
+        // Connection opened
+        socket.addEventListener('open', function (event) {
+            socket.send('Hello Server!');
+        });
+
+        socket.addEventListener('error', console.error)
+
+        // Listen for messages
+        socket.addEventListener('message', function (event) {
+            console.log('Message from server ', event.data);
+        });
+    </script>
+</head>
+<body>
+    
+</body>
+</html>
--- a/example/example.js
+++ b/example/example.js
@ -0,0 +1,3 @@
+const Wormhole = require('../index');
+
+const wormhole = new Wormhole({ urls: [ '/hello' ] });
--- a/index.js
+++ b/index.js
@ -0,0 +1,58 @@
+const http = require('http');
+
+const { createLog } = require('./lib/logger');
+const handshake = require('./lib/handshake');
+const constants = require('./lib/constants');
+const Socket = require('./lib/Socket');
+
+const handshakeLog = createLog([ 'Wormhole', 'Handshake' ]);
+
+class Wormhole {
+    constructor({ urls=[ '/bruh' ], port=8080 }) {
+        this._urls = urls;
+        this._port = port;
+
+        this._httpServer = http.createServer((req, res) => {
+            if (req.method === 'GET' && req.url && this._urls.includes(req.url)) {
+                handshakeLog(`Got connection request to ${req.url} on port ${this._port}`);
+
+                const failConnection = (status=400) => {
+                    res.writeHead(status);
+                    res.end();
+
+                    console.trace();
+                };
+
+                const websocketKey = req.headers['sec-websocket-key'];
+                const upgradeHeader = req.headers['upgrade'];
+                const websocketVersion = req.headers['sec-websocket-version'];
+
+                if (upgradeHeader !== constants.upgradeHeaderRequirement) return failConnection();
+                if (websocketVersion !== constants.websocketVersionRequirement) return failConnection();
+
+                const websocketAccept = handshake.generateWebsocketAcceptValue(websocketKey);
+
+                handshakeLog(websocketKey, websocketAccept);
+
+                if (websocketAccept) {
+                    res.writeHead(101, {
+                        'Upgrade': 'websocket',
+                        'Connection': 'Upgrade',
+                        'Sec-WebSocket-Accept': websocketAccept
+                    });
+                    res.end();
+
+                    const socket = new Socket({ socket: res.socket, initalState: 'CONNECTED' });
+
+                    return true;
+                }
+
+                return failConnection();
+            }
+        });
+
+        this._httpServer.listen(port);
+    }
+}
+
+module.exports = Wormhole;
--- a/lib/Socket.js
+++ b/lib/Socket.js
@ -0,0 +1,12 @@
+class Socket {
+    constructor({ initialState='CONNECTING', socket }) {
+        this._state = initialState;
+        this._socket = socket;
+
+        this._socket.on('data', (e) => {
+            console.log(e.toString());
+        });
+    }
+}
+
+module.exports = Socket;
--- a/lib/constants.js
+++ b/lib/constants.js
@ -0,0 +1,5 @@
+module.exports = {
+    handshakeGUID: '258EAFA5-E914-47DA-95CA-C5AB0DC85B11',
+    upgradeHeaderRequirement: 'websocket',
+    websocketVersionRequirement: '13'
+}
--- a/lib/handshake.js
+++ b/lib/handshake.js
@ -0,0 +1,17 @@
+const crypto = require('crypto');
+
+const { handshakeGUID } = require('./constants');
+
+const generateWebsocketAcceptValue = (websocketKey) => {
+    if (typeof websocketKey !== 'string' || typeof handshakeGUID !== 'string') {
+        // TODO: maybe throw error?
+        return;
+    }
+
+    const concatenated = websocketKey + handshakeGUID;
+    const sha1HashedInBase64 = crypto.createHash('sha1').update(concatenated, 'binary').digest('base64');
+    
+    return sha1HashedInBase64;
+};
+
+module.exports = { generateWebsocketAcceptValue };
--- a/lib/logger.js
+++ b/lib/logger.js
@ -0,0 +1,16 @@
+const logDebug = true;
+
+module.exports = {
+    createLog: (components) => (...args) => {
+        let compString = '';
+        for (const i in components) {
+            const component = components[i];
+            if (i >= (components.length - 1)) {
+                compString += `[${component}]`;
+            } else {
+                compString += `[${component}] `;
+            }
+        }
+        logDebug && console.log(compString, ...args);    
+    }
+};