initial files

server_node/server.js

@@ -0,0 +1,312 @@
+#!/usr/bin/node
+
+const WebSocket = require('ws');
+const crypto = require('crypto');
+
+const MAX_PEERS = 4096;
+const MAX_LOBBIES = 1024;
+const PORT = 9080;
+const ALFNUM = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789';
+
+const NO_LOBBY_TIMEOUT = 1000;
+const SEAL_CLOSE_TIMEOUT = 10000;
+const PING_INTERVAL = 10000;
+
+const STR_NO_LOBBY = 'Have not joined lobby yet';
+const STR_HOST_DISCONNECTED = 'Room host has disconnected';
+const STR_ONLY_HOST_CAN_SEAL = 'Only host can seal the lobby';
+const STR_SEAL_COMPLETE = 'Seal complete';
+const STR_TOO_MANY_LOBBIES = 'Too many lobbies open, disconnecting';
+const STR_ALREADY_IN_LOBBY = 'Already in a lobby';
+const STR_LOBBY_DOES_NOT_EXISTS = 'Lobby does not exists';
+const STR_LOBBY_IS_SEALED = 'Lobby is sealed';
+const STR_INVALID_FORMAT = 'Invalid message format';
+const STR_NEED_LOBBY = 'Invalid message when not in a lobby';
+const STR_SERVER_ERROR = 'Server error, lobby not found';
+const STR_INVALID_DEST = 'Invalid destination';
+const STR_INVALID_CMD = 'Invalid command';
+const STR_TOO_MANY_PEERS = 'Too many peers connected';
+const STR_INVALID_TRANSFER_MODE = 'Invalid transfer mode, must be text';
+
+const CMD = {
+	JOIN: 0, // eslint-disable-line sort-keys
+	ID: 1, // eslint-disable-line sort-keys
+	PEER_CONNECT: 2, // eslint-disable-line sort-keys
+	PEER_DISCONNECT: 3, // eslint-disable-line sort-keys
+	OFFER: 4, // eslint-disable-line sort-keys
+	ANSWER: 5, // eslint-disable-line sort-keys
+	CANDIDATE: 6, // eslint-disable-line sort-keys
+	SEAL: 7, // eslint-disable-line sort-keys
+};
+
+const HttpsServer = require('https').createServer;
+const fs = require("fs");
+const SSL_CERT_PATH = "/etc/letsencrypt/live/www.wolfang.info.ve/cert.pem"
+const SSL_KEY_PATH = "/etc/letsencrypt/live/www.wolfang.info.ve/privkey.pem"
+	
+
+https_server = HttpsServer({
+    cert: fs.readFileSync(SSL_CERT_PATH),
+    key: fs.readFileSync(SSL_KEY_PATH)
+}).listen(PORT, "0.0.0.0")
+
+function randomInt(low, high) {
+	return Math.floor(Math.random() * (high - low + 1) + low);
+}
+
+function randomId() {
+	return Math.abs(new Int32Array(crypto.randomBytes(4).buffer)[0]);
+}
+
+function randomSecret() {
+	let out = '';
+	for (let i = 0; i < 16; i++) {
+		out += ALFNUM[randomInt(0, ALFNUM.length - 1)];
+	}
+	return out;
+}
+
+function ProtoMessage(type, id, data) {
+	return JSON.stringify({
+		'type': type,
+		'id': id,
+		'data': data || '',
+	});
+}
+
+const wss = new WebSocket.Server({
+	server: https_server
+	// port: PORT,
+	// host : '0.0.0.0' 
+});
+
+class ProtoError extends Error {
+	constructor(code, message) {
+		super(message);
+		this.code = code;
+	}
+}
+
+class Peer {
+	constructor(id, ws) {
+		this.id = id;
+		this.ws = ws;
+		this.lobby = '';
+		// Close connection after 1 sec if client has not joined a lobby
+		this.timeout = setTimeout(() => {
+			if (!this.lobby) {
+				ws.close(4000, STR_NO_LOBBY);
+			}
+		}, NO_LOBBY_TIMEOUT);
+	}
+}
+
+class Lobby {
+	constructor(name, host, mesh) {
+		this.name = name;
+		this.host = host;
+		this.mesh = mesh;
+		this.peers = [];
+		this.sealed = false;
+		this.closeTimer = -1;
+	}
+
+	getPeerId(peer) {
+		if (this.host === peer.id) {
+			return 1;
+		}
+		return peer.id;
+	}
+
+	join(peer) {
+		const assigned = this.getPeerId(peer);
+		peer.ws.send(ProtoMessage(CMD.ID, assigned, this.mesh ? 'true' : ''));
+		this.peers.forEach((p) => {
+			p.ws.send(ProtoMessage(CMD.PEER_CONNECT, assigned));
+			peer.ws.send(ProtoMessage(CMD.PEER_CONNECT, this.getPeerId(p)));
+		});
+		this.peers.push(peer);
+	}
+
+	leave(peer) {
+		const idx = this.peers.findIndex((p) => peer === p);
+		if (idx === -1) {
+			return false;
+		}
+		const assigned = this.getPeerId(peer);
+		const close = assigned === 1;
+		this.peers.forEach((p) => {
+			if (close) { // Room host disconnected, must close.
+				p.ws.close(4000, STR_HOST_DISCONNECTED);
+			} else { // Notify peer disconnect.
+				p.ws.send(ProtoMessage(CMD.PEER_DISCONNECT, assigned));
+			}
+		});
+		this.peers.splice(idx, 1);
+		if (close && this.closeTimer >= 0) {
+			// We are closing already.
+			clearTimeout(this.closeTimer);
+			this.closeTimer = -1;
+		}
+		return close;
+	}
+
+	seal(peer) {
+		// Only host can seal
+		if (peer.id !== this.host) {
+			throw new ProtoError(4000, STR_ONLY_HOST_CAN_SEAL);
+		}
+		this.sealed = true;
+		this.peers.forEach((p) => {
+			p.ws.send(ProtoMessage(CMD.SEAL, 0));
+		});
+		console.log(`Peer ${peer.id} sealed lobby ${this.name} `
+			+ `with ${this.peers.length} peers`);
+		this.closeTimer = setTimeout(() => {
+			// Close peer connection to host (and thus the lobby)
+			this.peers.forEach((p) => {
+				p.ws.close(1000, STR_SEAL_COMPLETE);
+			});
+		}, SEAL_CLOSE_TIMEOUT);
+	}
+}
+
+const lobbies = new Map();
+let peersCount = 0;
+
+function joinLobby(peer, pLobby, mesh) {
+	let lobbyName = pLobby;
+	if (lobbyName === '') {
+		if (lobbies.size >= MAX_LOBBIES) {
+			throw new ProtoError(4000, STR_TOO_MANY_LOBBIES);
+		}
+		// Peer must not already be in a lobby
+		if (peer.lobby !== '') {
+			throw new ProtoError(4000, STR_ALREADY_IN_LOBBY);
+		}
+		lobbyName = randomSecret();
+		lobbies.set(lobbyName, new Lobby(lobbyName, peer.id, mesh));
+		console.log(`Peer ${peer.id} created lobby ${lobbyName}`);
+		console.log(`Open lobbies: ${lobbies.size}`);
+	}
+	const lobby = lobbies.get(lobbyName);
+	if (!lobby) {
+		throw new ProtoError(4000, STR_LOBBY_DOES_NOT_EXISTS);
+	}
+	if (lobby.sealed) {
+		throw new ProtoError(4000, STR_LOBBY_IS_SEALED);
+	}
+	peer.lobby = lobbyName;
+	console.log(`Peer ${peer.id} joining lobby ${lobbyName} `
+		+ `with ${lobby.peers.length} peers`);
+	lobby.join(peer);
+	peer.ws.send(ProtoMessage(CMD.JOIN, 0, lobbyName));
+}
+
+function parseMsg(peer, msg) {
+	let json = null;
+	try {
+		json = JSON.parse(msg);
+	} catch (e) {
+		throw new ProtoError(4000, STR_INVALID_FORMAT);
+	}
+
+	const type = typeof (json['type']) === 'number' ? Math.floor(json['type']) : -1;
+	const id = typeof (json['id']) === 'number' ? Math.floor(json['id']) : -1;
+	const data = typeof (json['data']) === 'string' ? json['data'] : '';
+
+	if (type < 0 || id < 0) {
+		throw new ProtoError(4000, STR_INVALID_FORMAT);
+	}
+
+	// Lobby joining.
+	if (type === CMD.JOIN) {
+		joinLobby(peer, data, id === 0);
+		return;
+	}
+
+	if (!peer.lobby) {
+		throw new ProtoError(4000, STR_NEED_LOBBY);
+	}
+	const lobby = lobbies.get(peer.lobby);
+	if (!lobby) {
+		throw new ProtoError(4000, STR_SERVER_ERROR);
+	}
+
+	// Lobby sealing.
+	if (type === CMD.SEAL) {
+		lobby.seal(peer);
+		return;
+	}
+
+	// Message relaying format:
+	//
+	// {
+	//   "type": CMD.[OFFER|ANSWER|CANDIDATE],
+	//   "id": DEST_ID,
+	//   "data": PAYLOAD
+	// }
+	if (type === CMD.OFFER || type === CMD.ANSWER || type === CMD.CANDIDATE) {
+		let destId = id;
+		if (id === 1) {
+			destId = lobby.host;
+		}
+		const dest = lobby.peers.find((e) => e.id === destId);
+		// Dest is not in this room.
+		if (!dest) {
+			throw new ProtoError(4000, STR_INVALID_DEST);
+		}
+		dest.ws.send(ProtoMessage(type, lobby.getPeerId(peer), data));
+		return;
+	}
+	throw new ProtoError(4000, STR_INVALID_CMD);
+}
+
+wss.on('connection', (ws) => {
+	if (peersCount >= MAX_PEERS) {
+		ws.close(4000, STR_TOO_MANY_PEERS);
+		return;
+	}
+	peersCount++;
+	const id = randomId();
+	const peer = new Peer(id, ws);
+	ws.on('message', (message) => {
+		if (typeof message !== 'string') {
+			ws.close(4000, STR_INVALID_TRANSFER_MODE);
+			return;
+		}
+		try {
+			parseMsg(peer, message);
+		} catch (e) {
+			const code = e.code || 4000;
+			console.log(`Error parsing message from ${id}:\n${
+				message}`);
+			ws.close(code, e.message);
+		}
+	});
+	ws.on('close', (code, reason) => {
+		peersCount--;
+		console.log(`Connection with peer ${peer.id} closed `
+			+ `with reason ${code}: ${reason}`);
+		if (peer.lobby && lobbies.has(peer.lobby)
+			&& lobbies.get(peer.lobby).leave(peer)) {
+			lobbies.delete(peer.lobby);
+			console.log(`Deleted lobby ${peer.lobby}`);
+			console.log(`Open lobbies: ${lobbies.size}`);
+			peer.lobby = '';
+		}
+		if (peer.timeout >= 0) {
+			clearTimeout(peer.timeout);
+			peer.timeout = -1;
+		}
+	});
+	ws.on('error', (error) => {
+		console.error(error);
+	});
+});
+
+const interval = setInterval(() => { // eslint-disable-line no-unused-vars
+	wss.clients.forEach((ws) => {
+		ws.ping();
+	});
+}, PING_INTERVAL);