fix traffic logging for socks5 udp

handler/socks/v4/handler.go

@@ -207,6 +207,30 @@ func (h *socks4Handler) handleConnect(ctx context.Context, conn net.Conn, req *g
 	})
 	log.Debugf("%s >> %s", conn.RemoteAddr(), addr)
 
+	{
+		clientID := ctxvalue.ClientIDFromContext(ctx)
+		rw := traffic_wrapper.WrapReadWriter(
+			h.limiter,
+			conn,
+			string(clientID),
+			limiter.ScopeOption(limiter.ScopeClient),
+			limiter.ServiceOption(h.options.Service),
+			limiter.NetworkOption("tcp"),
+			limiter.AddrOption(addr),
+			limiter.ClientOption(string(clientID)),
+			limiter.SrcOption(conn.RemoteAddr().String()),
+		)
+		if h.options.Observer != nil {
+			pstats := h.stats.Stats(string(clientID))
+			pstats.Add(stats.KindTotalConns, 1)
+			pstats.Add(stats.KindCurrentConns, 1)
+			defer pstats.Add(stats.KindCurrentConns, -1)
+			rw = stats_wrapper.WrapReadWriter(rw, pstats)
+		}
+
+		conn = xnet.NewReadWriteConn(rw, rw, conn)
+	}
+
 	if h.options.Bypass != nil && h.options.Bypass.Contains(ctx, "tcp", addr) {
 		resp := gosocks4.NewReply(gosocks4.Rejected, nil)
 		log.Trace(resp)
@@ -237,30 +261,6 @@ func (h *socks4Handler) handleConnect(ctx context.Context, conn net.Conn, req *g
 		return err
 	}
 
-	{
-		clientID := ctxvalue.ClientIDFromContext(ctx)
-		rw := traffic_wrapper.WrapReadWriter(
-			h.limiter,
-			conn,
-			string(clientID),
-			limiter.ScopeOption(limiter.ScopeClient),
-			limiter.ServiceOption(h.options.Service),
-			limiter.NetworkOption("tcp"),
-			limiter.AddrOption(addr),
-			limiter.ClientOption(string(clientID)),
-			limiter.SrcOption(conn.RemoteAddr().String()),
-		)
-		if h.options.Observer != nil {
-			pstats := h.stats.Stats(string(clientID))
-			pstats.Add(stats.KindTotalConns, 1)
-			pstats.Add(stats.KindCurrentConns, 1)
-			defer pstats.Add(stats.KindCurrentConns, -1)
-			rw = stats_wrapper.WrapReadWriter(rw, pstats)
-		}
-
-		conn = xnet.NewReadWriteConn(rw, rw, conn)
-	}
-
 	if h.md.sniffing {
 		if h.md.sniffingTimeout > 0 {
 			conn.SetReadDeadline(time.Now().Add(h.md.sniffingTimeout))