fix: resolve nethernet connection, ban deadlock, and nil RemoteAddr crashes

server/server.go

@@ -349,33 +349,64 @@ func (srv *Server) listen(l Listener) {
 		wg.Add(1)
 		go func() {
 			defer wg.Done()
+			defer func() {
+				if r := recover(); r != nil {
+					srv.conf.Log.Error(fmt.Sprintf("panic handling connection: %v", r))
+					_ = c.Close()
+				}
+			}()
+
 			name := c.IdentityData().DisplayName
 			xuid := c.IdentityData().XUID
 			uuidStr := c.IdentityData().Identity
+
+			// Safely extract IP - nethernet/local connections may
+			// return nil RemoteAddr or non-standard address formats.
 			ip := ""
 			if addr := c.RemoteAddr(); addr != nil {
-				if host, _, err := net.SplitHostPort(addr.String()); err == nil {
-					ip = host
-				} else {
-					ip = addr.String()
+				addrStr := addr.String()
+				if addrStr != "" {
+					if host, _, err := net.SplitHostPort(addrStr); err == nil {
+						ip = host
+					} else {
+						ip = addrStr
+					}
 				}
 			}
+
+			srv.conf.Log.Debug("Player connecting...", "name", name, "xuid", xuid, "ip", ip)
+
+			// Check if player is banned (by name, XUID, or UUID only - not IP).
 			if entry, banned := player.Bans.IsBanned(name, xuid, uuidStr, ip); banned {
 				msg := "You are banned from this server."
+				if entry.Reason != "" {
+					msg += " Reason: " + entry.Reason
+				}
 				if !entry.ExpiresAt.IsZero() {
 					timeLeft := time.Until(entry.ExpiresAt).Round(time.Second)
-					msg = fmt.Sprintf("You are banned from this server. Remaining time: %v", timeLeft)
+					if timeLeft > 0 {
+						msg += fmt.Sprintf(" Remaining: %v", timeLeft)
+					}
 				}
+				srv.conf.Log.Debug("Player banned, rejecting.", "name", name)
 				_ = c.WritePacket(&packet.Disconnect{Message: msg})
 				_ = c.Close()
 				return
 			}
-			if srv.PlayerCount() >= 14 && !strings.EqualFold(name, "XTarnaWijaya") && !strings.EqualFold(name, "TarnaWijaya") {
+
+			// Use the configured MaxPlayerCount instead of a hardcoded value.
+			// Admins bypass the player limit.
+			if srv.PlayerCount() >= srv.MaxPlayerCount() &&
+				!strings.EqualFold(name, "XTarnaWijaya") &&
+				!strings.EqualFold(name, "TarnaWijaya") {
+				srv.conf.Log.Debug("Server full, rejecting.", "name", name)
 				_ = c.WritePacket(&packet.Disconnect{Message: "Server is full."})
 				_ = c.Close()
 				return
 			}
+
 			if msg, ok := srv.conf.Allower.Allow(c.RemoteAddr(), c.IdentityData(), c.ClientData()); !ok {
+				srv.conf.Log.Debug("Player not allowed.", "name", name, "msg", msg)
 				_ = c.WritePacket(&packet.Disconnect{HideDisconnectionScreen: msg == "", Message: msg})
 				_ = c.Close()
 				return
@@ -469,12 +500,20 @@ func (srv *Server) finaliseConn(ctx context.Context, conn session.Conn, l Listen
 	if err := conn.StartGameContext(ctx, data); err != nil {
 		_ = l.Disconnect(conn, "Connection timeout.")
 
-		srv.conf.Log.Debug("spawn failed: "+err.Error(), "raddr", conn.RemoteAddr())
+		raddr := "nethernet"
+		if addr := conn.RemoteAddr(); addr != nil {
+			raddr = addr.String()
+		}
+		srv.conf.Log.Debug("spawn failed: "+err.Error(), "raddr", raddr)
 		return
 	}
 	if _, ok := srv.Player(id); ok {
 		_ = l.Disconnect(conn, "Already logged in.")
-		srv.conf.Log.Debug("spawn failed: already logged in", "raddr", conn.RemoteAddr())
+		raddr := "nethernet"
+		if addr := conn.RemoteAddr(); addr != nil {
+			raddr = addr.String()
+		}
+		srv.conf.Log.Debug("spawn failed: already logged in", "raddr", raddr)
 		return
 	}
 	_ = conn.WritePacket(&packet.ItemRegistry{Items: srv.customItems})