Allow server host to decide peer to peer behavior

.gitignore

@@ -1,2 +1,4 @@
 dist/
-node_modules/
+node_modules/
+config/*
+!config/*.example.*

README.md

@@ -28,6 +28,7 @@
 * [Getting Started](#getting-started)
   * [Prerequisites](#prerequisites)
   * [Installation](#installation)
+  * [Customizing Peer to Peer Behavior](#customizing-peer-to-peer-behavior)
 * [Contributing](#contributing)
 * [License](#license)
 
@@ -54,7 +55,7 @@ To get up and running quickly, you can deploy to Heroku using the button below
 
 [![Deploy](https://www.herokucdn.com/deploy/button.svg)](https://heroku.com/deploy)
 
-This will deploy an instance of the crewlink-server. You can get the URL of your server by using the app name that you gave when you launched the app on heroku and appending `.herokuapp.com`. You can also find the URL of your server by going to "Settings", scrolling down to "Domains", and removing the `https://` and trailing slash from the url. Using this URL, follow step 4 of the [installation instructions](https://github.com/ottomated/CrewLink-server#manual-installation) to connect your client to your server instance.
+This will deploy an instance of the crewlink-server. You can get the URL of your server by using the app name that you gave when you launched the app on heroku and appending `.herokuapp.com`. You can also find the URL of your server by going to "Settings", scrolling down to "Domains". Using this URL, follow step 4 of the [installation instructions](https://github.com/ottomated/CrewLink-server#manual-installation) to connect your client to your server instance.
 
 ## Docker Quickstart
 
@@ -111,8 +112,30 @@ yarn install
 ```JS
 yarn start
 ```
-4. Copy your server's IP and port into CrewLink settings. Make sure everyone in your lobby is using the same server.
-
+4. Copy your server URL into CrewLink settings. Make sure everyone in your lobby is using the same server.
+### Customizing Peer to Peer Behavior
+CrewLink-server should work out of the box for most people. You may, however, come across people who are unable to hear 
+other people, no matter what they try. This could be because of a NAT or firewall that is preventing peer to peer
+connections. In this case you may want to set up your own relay server to act as a middleman for your voice traffic.
+CrewLink needs a specific type of server for this called a TURN server.
+
+You can configure a TURN server by creating a file called ``peerConfig.yml`` in the config folder. Use the
+provided example as a template. A good, open source TURN server implementation is 
+[Coturn](https://github.com/coturn/coturn). A relay server may also be desirable in case you want to prevent CrewLink 
+players from detecting the IP addresses of everyone in the same Among Us room using your voice server.
+
+CAUTION: Hosting your own TURN server is a great way to solve most connection issues but they're not without problems.
+These servers, by design, let anyone with the credentials relay packets to anywhere. Because you are sending the TURN 
+credentials to everyone connecting to your CrewLink server, obtaining them becomes very easy. If you choose to set one 
+up, make sure you:
+  - Know what you're doing
+  - Configure the server in a way that disallows relaying packets to places that make no sense (localhost, private networks, etc)
+  - Consider limiting the bandwidth per user and across the whole TURN server
+  - Keep an eye on TURN server activity while you're running one
+  - Change TURN credentials regularly
+  - This list is not exhaustive, see point 1
+
+It is because of this that you should only deploy a TURN server for small, private CrewLink servers.
 <!-- CONTRIBUTING -->
 ## Contributing
 

config/peerConfig.example.yml

@@ -0,0 +1,35 @@
+# IN ORDER TO USE THIS CONFIG FILE, RENAME IT AND REMOVE THE ".example" PART OF THE FILENAME!
+#
+# CrewLink peer to peer connection configuration.
+#
+# This file lets you modify how CrewLink connects players to each other.
+#
+# CrewLink uses peer to peer connections to send voice and game state data between players. This means that every player
+# has to be able to connect to every other player some way or another in order for CrewLink to work. Below you can tweak
+# the mechanisms CrewLink uses to establish peer to peer connections.
+
+# Force CrewLink to only work through TURN servers. This is great if you want to protect the IP addresses of players
+# as no direct connection will be made. At least one TURN server is required if set to true.
+forceRelayOnly: false
+
+# If you run into connection issues, you may want to add your own TURN server here.
+#
+# CAUTION: Hosting your own TURN server is a great way to solve most connection issues but they're not without problems.
+# These servers, by design, let anyone with the credentials relay packets to anywhere. Because you are sending the TURN 
+# credentials to everyone connecting to your CrewLink server, obtaining them becomes very easy. If you choose to set one 
+# up, make sure you:
+#    - Know what you're doing
+#    - Configure the server in a way that disallows relaying packets to places that make no sense (localhost, private networks, etc)
+#    - Consider limiting the bandwidth per user and across the whole TURN server
+#    - Keep an eye on TURN server activity while you're running one
+#    - Change TURN credentials regularly
+#    - This list is not exhaustive, see point 1
+iceServers:
+  # Google's STUN server is used by default
+  - urls: 'stun:stun.l.google.com:19302'
+#   - urls: 'turn:example.com'
+#     username: 'TurnUsername'
+#     credential: 'TurnPassword'
+#   - urls: 'stun:example.com'
+#     username: 'StunUsername'
+#     credential: 'StunPassword'

package.json

@@ -8,7 +8,8 @@
   "morgan": "^1.10.0",
   "pug": "^3.0.0",
   "socket.io": "^2.3.0",
-  "tracer": "^1.1.4"
+  "tracer": "^1.1.4",
+  "yaml": "^1.10.0"
  },
  "scripts": {
   "start": "yarn compile && node dist/index.js",

src/ICEServer.ts

@@ -0,0 +1,5 @@
+export interface ICEServer {
+	urls: string|string[];
+	username?: string;
+	credential?: string;
+}

src/index.ts

@@ -1,11 +1,13 @@
 import express from 'express';
 import { Server } from 'http';
 import { Server as HttpsServer } from 'https';
-import { readFileSync, readdirSync } from 'fs';
+import { readFileSync } from 'fs';
 import { join } from 'path';
 import socketIO from 'socket.io';
 import Tracer from 'tracer';
 import morgan from 'morgan';
+import peerConfig  from './peerConfig';
+import { ICEServer } from './ICEServer';
 
 const supportedCrewLinkVersions = new Set(['1.2.0', '1.2.1']);
 const httpsEnabled = !!process.env.HTTPS;
@@ -28,6 +30,13 @@ if (httpsEnabled) {
 } else {
 	server = new Server(app);
 }
+
+let address = process.env.ADDRESS;
+if (!address) {
+	logger.error('You must set the ADDRESS environment variable.');
+	process.exit(1);
+}
+
 const io = socketIO(server);
 
 const clients = new Map<string, Client>();
@@ -42,15 +51,15 @@ interface Signal {
 	to: string;
 }
 
-app.set('view engine', 'pug')
-app.use(morgan('combined'))
+interface ClientPeerConfig {
+	forceRelayOnly: boolean;
+	iceServers: ICEServer[]
+}
+
+app.set('view engine', 'pug');
+app.use(morgan('combined'));
 
 let connectionCount = 0;
-let address = process.env.ADDRESS;
-if (!address) {
-	logger.error('You must set the ADDRESS environment variable.');
-	process.exit(1);
-}
 
 app.get('/', (_, res) => {
 	res.render('index', { connectionCount, address });
@@ -88,6 +97,13 @@ io.on('connection', (socket: socketIO.Socket) => {
 	logger.info("Total connected: %d", connectionCount);
 	let code: string | null = null;
 
+	const clientPeerConfig: ClientPeerConfig = {
+		forceRelayOnly: peerConfig.forceRelayOnly,
+		iceServers: peerConfig.iceServers? [...peerConfig.iceServers] : []
+	}
+
+	socket.emit('clientPeerConfig', clientPeerConfig);
+
 	socket.on('join', (c: string, id: number, clientId: number) => {
 		if (typeof c !== 'string' || typeof id !== 'number' || typeof clientId !== 'number') {
 			socket.disconnect();
@@ -163,10 +179,7 @@ io.on('connection', (socket: socketIO.Socket) => {
 		connectionCount--;
 		logger.info("Total connected: %d", connectionCount);
 	})
-
-})
+});
 
 server.listen(port);
-(async () => {
-	logger.info('CrewLink Server started: %s', address);
-})();
+logger.info('CrewLink Server started: %s', address);

src/peerConfig.ts

@@ -0,0 +1,31 @@
+import YAML from 'yaml';
+import path from 'path';
+import fs from 'fs';
+import { ICEServer } from './ICEServer';
+
+const PEER_CONFIG_PATH = path.join(__dirname, '..', 'config', 'peerConfig.yml');
+
+interface PeerConfig {
+	forceRelayOnly: boolean;
+	iceServers?: ICEServer[]
+}
+
+const DEFAULT_PEER_CONFIG: PeerConfig = {
+	forceRelayOnly: false,
+	iceServers: [
+		{
+			urls: 'stun:stun.l.google.com:19302'
+		}
+	]
+};
+
+let peerConfig = DEFAULT_PEER_CONFIG;
+if (fs.existsSync(PEER_CONFIG_PATH)) {
+	try {
+		peerConfig = YAML.parse(fs.readFileSync(PEER_CONFIG_PATH).toString('utf8'));
+	} catch (err) {
+		console.error(`Unable to load peer config file. Make sure it is valid YAML.\n${err}`);
+	}
+}
+
+export default peerConfig

yarn.lock

@@ -2,22 +2,22 @@
 # yarn lockfile v1
 
 
-"@babel/helper-validator-identifier@^7.10.4":
-  version "7.10.4"
-  resolved "https://registry.yarnpkg.com/@babel/helper-validator-identifier/-/helper-validator-identifier-7.10.4.tgz#a78c7a7251e01f616512d31b10adcf52ada5e0d2"
-  integrity sha512-3U9y+43hz7ZM+rzG24Qe2mufW5KhvFg/NhnNph+i9mgCtdTCtMJuI1TMkrIUiK7Ix4PYlRF9I5dhqaLYA/ADXw==
+"@babel/helper-validator-identifier@^7.12.11":
+  version "7.12.11"
+  resolved "https://registry.yarnpkg.com/@babel/helper-validator-identifier/-/helper-validator-identifier-7.12.11.tgz#c9a1f021917dcb5ccf0d4e453e399022981fc9ed"
+  integrity sha512-np/lG3uARFybkoHokJUmf1QfEvRVCPbmQeUQpKow5cQ3xWrV9i3rUHodKDJPQfTVX61qKi+UdYk8kik84n7XOw==
 
 "@babel/parser@^7.6.0", "@babel/parser@^7.9.6":
-  version "7.12.7"
-  resolved "https://registry.yarnpkg.com/@babel/parser/-/parser-7.12.7.tgz#fee7b39fe809d0e73e5b25eecaf5780ef3d73056"
-  integrity sha512-oWR02Ubp4xTLCAqPRiNIuMVgNO5Aif/xpXtabhzW2HWUD47XJsAB4Zd/Rg30+XeQA3juXigV7hlquOTmwqLiwg==
+  version "7.12.11"
+  resolved "https://registry.yarnpkg.com/@babel/parser/-/parser-7.12.11.tgz#9ce3595bcd74bc5c466905e86c535b8b25011e79"
+  integrity sha512-N3UxG+uuF4CMYoNj8AhnbAcJF0PiuJ9KHuy1lQmkYsxTer/MAH9UBNHsBoAX/4s6NvlDD047No8mYVGGzLL4hg==
 
 "@babel/types@^7.6.1", "@babel/types@^7.9.6":
-  version "7.12.7"
-  resolved "https://registry.yarnpkg.com/@babel/types/-/types-7.12.7.tgz#6039ff1e242640a29452c9ae572162ec9a8f5d13"
-  integrity sha512-MNyI92qZq6jrQkXvtIiykvl4WtoRrVV9MPn+ZfsoEENjiWcBQ3ZSHrkxnJWgWtLX3XXqX5hrSQ+X69wkmesXuQ==
+  version "7.12.12"
+  resolved "https://registry.yarnpkg.com/@babel/types/-/types-7.12.12.tgz#4608a6ec313abbd87afa55004d373ad04a96c299"
+  integrity sha512-lnIX7piTxOH22xE7fDXDbSHg9MM1/6ORnafpJmov5rs0kX5g4BZxeXNJLXsMRiO0U5Rb8/FvMS6xlTnTHvxonQ==
   dependencies:
-    "@babel/helper-validator-identifier" "^7.10.4"
+    "@babel/helper-validator-identifier" "^7.12.11"
     lodash "^4.17.19"
     to-fast-properties "^2.0.0"
 
@@ -30,9 +30,9 @@
     "@types/node" "*"
 
 "@types/connect@*":
-  version "3.4.33"
-  resolved "https://registry.yarnpkg.com/@types/connect/-/connect-3.4.33.tgz#31610c901eca573b8713c3330abc6e6b9f588546"
-  integrity sha512-2+FrkXY4zllzTNfJth7jOqEHC+enpLeGslEhpnTAkg21GkRrWV4SsAtqchtT4YS9/nODBU2/ZfsBY2X4J/dX7A==
+  version "3.4.34"
+  resolved "https://registry.yarnpkg.com/@types/connect/-/connect-3.4.34.tgz#170a40223a6d666006d93ca128af2beb1d9b1901"
+  integrity sha512-ePPA/JuI+X0vb+gSWlPKOY0NdNAie/rPUqX2GUPpbZwiKTkSPhjXWuee47E4MtE54QVzGCQMQkAL6JhV2E1+cQ==
   dependencies:
     "@types/node" "*"
 
@@ -44,18 +44,18 @@
     "@types/node" "*"
 
 "@types/express-serve-static-core@*":
-  version "4.17.13"
-  resolved "https://registry.yarnpkg.com/@types/express-serve-static-core/-/express-serve-static-core-4.17.13.tgz#d9af025e925fc8b089be37423b8d1eac781be084"
-  integrity sha512-RgDi5a4nuzam073lRGKTUIaL3eF2+H7LJvJ8eUnCI0wA6SNjXc44DCmWNiTLs/AZ7QlsFWZiw/gTG3nSQGL0fA==
+  version "4.17.17"
+  resolved "https://registry.yarnpkg.com/@types/express-serve-static-core/-/express-serve-static-core-4.17.17.tgz#6ba02465165b6c9c3d8db3a28def6b16fc9b70f5"
+  integrity sha512-YYlVaCni5dnHc+bLZfY908IG1+x5xuibKZMGv8srKkvtul3wUuanYvpIj9GXXoWkQbaAdR+kgX46IETKUALWNQ==
   dependencies:
     "@types/node" "*"
     "@types/qs" "*"
     "@types/range-parser" "*"
 
 "@types/express@^4.17.8":
-  version "4.17.8"
-  resolved "https://registry.yarnpkg.com/@types/express/-/express-4.17.8.tgz#3df4293293317e61c60137d273a2e96cd8d5f27a"
-  integrity sha512-wLhcKh3PMlyA2cNAB9sjM1BntnhPMiM0JOBwPBqttjHev2428MLEB4AYVN+d8s2iyCVZac+o41Pflm/ZH5vLXQ==
+  version "4.17.9"
+  resolved "https://registry.yarnpkg.com/@types/express/-/express-4.17.9.tgz#f5f2df6add703ff28428add52bdec8a1091b0a78"
+  integrity sha512-SDzEIZInC4sivGIFY4Sz1GG6J9UObPwCInYJjko2jzOf/Imx/dlpume6Xxwj1ORL82tBbmN4cPDIDkLbWHk9hw==
   dependencies:
     "@types/body-parser" "*"
     "@types/express-serve-static-core" "*"
@@ -75,9 +75,9 @@
     "@types/node" "*"
 
 "@types/node@*":
-  version "14.14.3"
-  resolved "https://registry.yarnpkg.com/@types/node/-/node-14.14.3.tgz#e1c09064121f894baaad2bd9f12ce4a41bffb274"
-  integrity sha512-33/L34xS7HVUx23e0wOT2V1qPF1IrHgQccdJVm9uXGTB9vFBrrzBtkQymT8VskeKOxjz55MSqMv0xuLq+u98WQ==
+  version "14.14.16"
+  resolved "https://registry.yarnpkg.com/@types/node/-/node-14.14.16.tgz#3cc351f8d48101deadfed4c9e4f116048d437b4b"
+  integrity sha512-naXYePhweTi+BMv11TgioE2/FXU4fSl29HAH1ffxVciNsH3rYXjNP2yM8wqmSm7jS20gM8TIklKiTen+1iVncw==
 
 "@types/qs@*":
   version "6.9.5"
@@ -90,20 +90,28 @@
   integrity sha512-ewFXqrQHlFsgc09MK5jP5iR7vumV/BYayNC6PgJO2LPe8vrnNFyjQjSppfEngITi0qvfKtzFvgKymGheFM9UOA==
 
 "@types/serve-static@*":
-  version "1.13.6"
-  resolved "https://registry.yarnpkg.com/@types/serve-static/-/serve-static-1.13.6.tgz#866b1b8dec41c36e28c7be40ac725b88be43c5c1"
-  integrity sha512-nuRJmv7jW7VmCVTn+IgYDkkbbDGyIINOeu/G0d74X3lm6E5KfMeQPJhxIt1ayQeQB3cSxvYs1RA/wipYoFB4EA==
+  version "1.13.8"
+  resolved "https://registry.yarnpkg.com/@types/serve-static/-/serve-static-1.13.8.tgz#851129d434433c7082148574ffec263d58309c46"
+  integrity sha512-MoJhSQreaVoL+/hurAZzIm8wafFR6ajiTM1m4A0kv6AGeVBl4r4pOV8bGFrjjq1sGxDTnCoF8i22o0/aE5XCyA==
   dependencies:
     "@types/mime" "*"
     "@types/node" "*"
 
+"@types/socket.io-parser@*":
+  version "2.2.1"
+  resolved "https://registry.yarnpkg.com/@types/socket.io-parser/-/socket.io-parser-2.2.1.tgz#dc94aed303839487f4975249a32a548109ea3647"
+  integrity sha512-+JNb+7N7tSINyXPxAJb62+NcpC1x/fPn7z818W4xeNCdPTp6VsO/X8fCsg6+ug4a56m1v9sEiTIIUKVupcHOFQ==
+  dependencies:
+    "@types/node" "*"
+
 "@types/socket.io@^2.1.11":
-  version "2.1.11"
-  resolved "https://registry.yarnpkg.com/@types/socket.io/-/socket.io-2.1.11.tgz#e0d6759880e5f9818d5297a3328b36641bae996b"
-  integrity sha512-bVprmqPhJMLb9ZCm8g0Xy8kwBFRbnanOWSxzWkDkkIwxTvud5tKMfAJymXX6LQbizUKCS1yima7JM4BeLqjNqA==
+  version "2.1.12"
+  resolved "https://registry.yarnpkg.com/@types/socket.io/-/socket.io-2.1.12.tgz#91187f826a5dd2ed1113e935815bbaf9627e5cb0"
+  integrity sha512-oStc5VFkpb0AsjOxQUj9ztX5Iziatyla/rjZTYbFGoVrrKwd+JU2mtxk7iSl5RGYx9WunLo6UXW1fBzQok/ZyA==
   dependencies:
     "@types/engine.io" "*"
     "@types/node" "*"
+    "@types/socket.io-parser" "*"
 
 accepts@~1.3.4, accepts@~1.3.7:
   version "1.3.7"
@@ -639,9 +647,9 @@ ms@2.1.1:
   integrity sha512-tgp+dl5cGk28utYktBsrFqA7HKgrhgPsg6Z/EfhWI4gl1Hwq8B/GmY/0oXZ6nF8hDVesS/FpnYaD/kOWhYQvyg==
 
 ms@^2.1.1:
-  version "2.1.2"
-  resolved "https://registry.yarnpkg.com/ms/-/ms-2.1.2.tgz#d09d1f357b443f493382a8eb3ccd183872ae6009"
-  integrity sha512-sGkPx+VjMtmA6MX27oA4FBFELFCZZ4S4XqeGOXCv68tT+jb3vk/RyaKWP0PTKyWtmLSM0b+adUTEvbs1PEaH2w==
+  version "2.1.3"
+  resolved "https://registry.yarnpkg.com/ms/-/ms-2.1.3.tgz#574c8138ce1d2b5861f0b44579dbadd60c6615b2"
+  integrity sha512-6FlzubTLZG3J2a/NVCAleEhjzq5oxgHyaCU9yYXvcLsvoVaHJq/s5xXI6/XXP6tz7R9xAOtHnSO/tXtF3WRTlA==
 
 negotiator@0.6.2:
   version "0.6.2"
@@ -1003,9 +1011,9 @@ type-is@~1.6.17, type-is@~1.6.18:
     mime-types "~2.1.24"
 
 typescript@^4.0.5:
-  version "4.0.5"
-  resolved "https://registry.yarnpkg.com/typescript/-/typescript-4.0.5.tgz#ae9dddfd1069f1cb5beb3ef3b2170dd7c1332389"
-  integrity sha512-ywmr/VrTVCmNTJ6iV2LwIrfG1P+lv6luD8sUJs+2eI9NLGigaN+nUQc13iHqisq7bra9lnmUSYqbJvegraBOPQ==
+  version "4.1.3"
+  resolved "https://registry.yarnpkg.com/typescript/-/typescript-4.1.3.tgz#519d582bd94cba0cf8934c7d8e8467e473f53bb7"
+  integrity sha512-B3ZIOf1IKeH2ixgHhj6la6xdwR9QrLC5d1VKeCSY4tvkqhF2eqd9O7txNlS0PO3GrBAFIdr3L1ndNwteUbZLYg==
 
 unpipe@1.0.0, unpipe@~1.0.0:
   version "1.0.0"
@@ -1038,9 +1046,9 @@ with@^7.0.0:
     babel-walk "3.0.0-canary-5"
 
 ws@^7.1.2:
-  version "7.3.1"
-  resolved "https://registry.yarnpkg.com/ws/-/ws-7.3.1.tgz#d0547bf67f7ce4f12a72dfe31262c68d7dc551c8"
-  integrity sha512-D3RuNkynyHmEJIpD2qrgVkc9DQ23OrN/moAwZX4L8DfvszsJxpjQuUq3LMx6HoYji9fbIOBY18XWBsAux1ZZUA==
+  version "7.4.1"
+  resolved "https://registry.yarnpkg.com/ws/-/ws-7.4.1.tgz#a333be02696bd0e54cea0434e21dcc8a9ac294bb"
+  integrity sha512-pTsP8UAfhy3sk1lSk/O/s4tjD0CRwvMnzvwr4OKGX7ZvqZtUyx4KIJB5JWbkykPoc55tixMGgTNoh3k4FkNGFQ==
 
 ws@~6.1.0:
   version "6.1.4"
@@ -1054,6 +1062,11 @@ xmlhttprequest-ssl@~1.5.4:
   resolved "https://registry.yarnpkg.com/xmlhttprequest-ssl/-/xmlhttprequest-ssl-1.5.5.tgz#c2876b06168aadc40e57d97e81191ac8f4398b3e"
   integrity sha1-wodrBhaKrcQOV9l+gRkayPQ5iz4=
 
+yaml@^1.10.0:
+  version "1.10.0"
+  resolved "https://registry.yarnpkg.com/yaml/-/yaml-1.10.0.tgz#3b593add944876077d4d683fee01081bd9fff31e"
+  integrity sha512-yr2icI4glYaNG+KWONODapy2/jDdMSDnrONSjblABjD9B4Z5LgiircSt8m8sRZFNi08kG9Sm0uSHtEmP3zaEGg==
+
 yeast@0.1.2:
   version "0.1.2"
   resolved "https://registry.yarnpkg.com/yeast/-/yeast-0.1.2.tgz#008e06d8094320c372dbc2f8ed76a0ca6c8ac419"