config: max_conn_per_ip for limiting maximum incomming connections per IP.

Signed-off-by: Yonle <yonle@lecturify.net>

bouncer.js

@@ -43,7 +43,7 @@ let zeroStats = {
 }
 let stats = {};
 
-function handleConnection(ws, req) {
+function handleConnection(ws, req, onClose) {
   let query = querystring.parse(req.url.slice(2));
   let authKey = null;
   let authorized = true;
@@ -147,6 +147,8 @@ function handleConnection(ws, req) {
 
   ws.on('error', console.error);
   ws.on('close', _ => {
+    onClose();
+
     delete idents[ws.ident];
 
     console.log(process.pid, "---", `${ws.ip} disconnected`);

config.js.example

@@ -53,6 +53,10 @@ module.exports = {
   // Setting as 0 will disable ratelimit handling.
   upstream_ratelimit_expiration: 10000,
 
+  // Maximum incomming connections per IP.
+  // By default, This is Infinity. Change the value as Integer (number) to override.
+  max_conn_per_ip: Infinity,
+
   // Maximum subscriptions that client could open.
   // Setting as -1 will disable max subscription limit.
   max_client_subs: -1,

http.js

@@ -18,6 +18,8 @@ const log = _ => console.log(process.pid, curD(), "-", _);
 let server = null;
 let config = require(process.env.BOSTR_CONFIG_PATH || "./config");
 
+let connectedHosts = [];
+
 let wslinkregex = /(?:^- )(wss?:\/\/.*)(?: \(.*\))/gm;
 let loadbalancerUpstreamLinks = [];
 
@@ -147,8 +149,11 @@ server.on('upgrade', (req, sock, head) => {
   const ip = req.headers["x-forwarded-for"]?.split(",")[0] || sock.address()?.address;
 
   if (config.blocked_hosts && config.blocked_hosts.includes(ip)) return sock.destroy();
+  if (connectedHosts.filter(i => i === ip).length >= (config.max_conn_per_ip || Infinity)) return sock.destroy();
 
-  wss.handleUpgrade(req, sock, head, _ => bouncer.handleConnection(_, req));
+  connectedHosts.push(ip);
+
+  wss.handleUpgrade(req, sock, head, _ => bouncer.handleConnection(_, req, _ => delete connectedHosts[connectedHosts.indexOf(ip)]));
 });
 
 const listened = server.listen(process.env.PORT || config.port, config.address || "0.0.0.0", _ => {