add express rate limiting

package-lock.json

@@ -26,6 +26,7 @@
         "dompurify": "^3.1.7",
         "dotenv": "^16.4.7",
         "express": "^4.21.1",
+        "express-rate-limit": "^7.5.0",
         "google-auth-library": "^9.14.0",
         "googleapis": "^143.0.0",
         "hammerjs": "^2.0.8",
@@ -8241,6 +8242,21 @@
         "node": ">= 0.10.0"
       }
     },
+    "node_modules/express-rate-limit": {
+      "version": "7.5.0",
+      "resolved": "https://registry.npmjs.org/express-rate-limit/-/express-rate-limit-7.5.0.tgz",
+      "integrity": "sha512-eB5zbQh5h+VenMPM3fh+nw1YExi5nMr6HUCR62ELSP11huvxm/Uir1H1QEyTkk5QX6A58pX6NmaTMceKZ0Eodg==",
+      "license": "MIT",
+      "engines": {
+        "node": ">= 16"
+      },
+      "funding": {
+        "url": "https://github.com/sponsors/express-rate-limit"
+      },
+      "peerDependencies": {
+        "express": "^4.11 || 5 || ^5.0.0-beta.1"
+      }
+    },
     "node_modules/express/node_modules/debug": {
       "version": "2.6.9",
       "resolved": "https://registry.npmjs.org/debug/-/debug-2.6.9.tgz",

package.json

@@ -89,6 +89,7 @@
     "dompurify": "^3.1.7",
     "dotenv": "^16.4.7",
     "express": "^4.21.1",
+    "express-rate-limit": "^7.5.0",
     "google-auth-library": "^9.14.0",
     "googleapis": "^143.0.0",
     "hammerjs": "^2.0.8",

src/server/Server.ts

@@ -22,6 +22,7 @@ import {
   validateUsername,
 } from "../core/validations/username";
 import { Request, Response } from "express";
+import rateLimit from "express-rate-limit";
 
 const __filename = fileURLToPath(import.meta.url);
 const __dirname = path.dirname(__filename);
@@ -34,6 +35,14 @@ const wss = new WebSocketServer({ server });
 app.use(express.static(path.join(__dirname, "../../out")));
 app.use(express.json());
 
+app.set("trust proxy", 2);
+app.use(
+  rateLimit({
+    windowMs: 1000, // 1 second
+    max: 20, // 20 requests per IP per second
+  }),
+);
+
 const gm = new GameManager(getServerConfig());
 
 const bot = new DiscordBot();
@@ -130,6 +139,14 @@ app.get("/private_lobby/:id", (req, res) => {
   });
 });
 
+app.get("/debug-ip", (req, res) => {
+  res.send({
+    "x-forwarded-for": req.headers["x-forwarded-for"],
+    "real-ip": req.ip,
+    "raw-headers": req.rawHeaders,
+  });
+});
+
 app.get("*", function (req, res) {
   // SPA routing
   res.sendFile(path.join(__dirname, "../../out/index.html"));

webpack.config.js

@@ -138,6 +138,7 @@ export default (env, argv) => {
                 "/lobby",
                 "/archive_singleplayer_game",
                 "/validate-username",
+                "/debug-ip",
               ],
               target: "http://localhost:3000",
               secure: false,