initial: ZeroTier-like P2P mesh VPN server with multi-tenant Web UI

cmd/zeromesh-relay/main.go

@@ -0,0 +1,62 @@
+package main
+
+import (
+	"context"
+	"flag"
+	"log/slog"
+	"os"
+	"os/signal"
+	"syscall"
+
+	"zeromesh/internal/config"
+	"zeromesh/internal/vl1"
+)
+
+func main() {
+	cfgPath := flag.String("config", "config.yaml", "config file path")
+	flag.Parse()
+
+	cfg, err := config.Load(*cfgPath)
+	if err != nil {
+		slog.Error("load config", "err", err)
+		os.Exit(1)
+	}
+
+	logger := slog.New(slog.NewTextHandler(os.Stderr, &slog.HandlerOptions{Level: slog.LevelInfo}))
+	slog.SetDefault(logger)
+
+	transport, err := vl1.NewTransport(cfg.Relay.ListenPort, logger)
+	if err != nil {
+		slog.Error("init relay transport", "err", err)
+		os.Exit(1)
+	}
+
+	slog.Info("relay started",
+		"realm", cfg.Relay.Realm,
+		"port", transport.Port(),
+	)
+
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	go func() {
+		buf := make([]byte, vl1.MaxPacketSize)
+		for {
+			n, addr, err := transport.ReadFrom(buf)
+			if err != nil {
+				if ctx.Err() != nil {
+					return
+				}
+				slog.Error("relay read", "err", err)
+				continue
+			}
+			logger.Debug("relay packet", "from", addr, "len", n)
+		}
+	}()
+
+	quit := make(chan os.Signal, 1)
+	signal.Notify(quit, syscall.SIGINT, syscall.SIGTERM)
+	<-quit
+	cancel()
+	transport.Close()
+}