support regex and player name sniff

client/client.go

@@ -191,7 +191,8 @@ func (c *Client) dispatchControl(payload []byte) {
 		pattern, _ := r.String()
 		ip, _ := r.String()
 		port, _ := r.U16()
-		go c.handleControlRequest(cid, pattern, ip, int(port))
+		username, _ := r.String()
+		go c.handleControlRequest(cid, pattern, ip, int(port), username)
 	case CtlPong:
 		// ignore
 	default:
@@ -217,12 +218,13 @@ func (c *Client) pingLoop(ctx context.Context, fc *wire.FramedConn) {
 
 // handleControlRequest reacts to a matched player: allocate a worker stream,
 // SYN it, and bridge it to the mapped destination.
-func (c *Client) handleControlRequest(cid []byte, pattern, ip string, port int) {
+func (c *Client) handleControlRequest(cid []byte, pattern, ip string, port int, username string) {
 	mapping, ok := c.mappings[NormalizeAddress(pattern)]
 	if !ok {
 		log.Printf("control-request for unmapped pattern %q; ignoring", pattern)
 		return
 	}
+	log.Printf("player %s:%d joined as %q via pattern %q -> %s", ip, port, username, pattern, mapping.Destination)
 	wc, sid, err := c.pool.Allocate()
 	if err != nil {
 		log.Printf("worker allocate failed: %v", err)

client/config.example.json

@@ -5,7 +5,7 @@
   "pingIntervalMs": 20000,
   "mappings": [
     {
-      "pattern": "mc.example.com",
+      "pattern": "mc\\.example\\.com",
       "destination": "127.0.0.1:25566",
       "proxyProtocol": true
     }