TUN inbound: Add traffic counters; Metrics: Rely on instance (#6349)

https://github.com/XTLS/Xray-core/pull/6349#issuecomment-4775121300

proxy/tun/handler.go

@@ -17,6 +17,7 @@ import (
 	"github.com/xtls/xray-core/core"
 	"github.com/xtls/xray-core/features/policy"
 	"github.com/xtls/xray-core/features/routing"
+	"github.com/xtls/xray-core/features/stats"
 	"github.com/xtls/xray-core/transport"
 	"github.com/xtls/xray-core/transport/internet"
 	"github.com/xtls/xray-core/transport/internet/stat"
@@ -32,6 +33,8 @@ type Handler struct {
 	dispatcher      routing.Dispatcher
 	tag             string
 	sniffingRequest session.SniffingRequest
+	uplinkCounter   stats.Counter
+	downlinkCounter stats.Counter
 }
 
 // ConnectionHandler interface with the only method that stack is going to push new connections to
@@ -59,6 +62,23 @@ func (t *Handler) Init(ctx context.Context, pm policy.Manager, dispatcher routin
 	t.policyManager = pm
 	t.dispatcher = dispatcher
 
+	if len(t.tag) > 0 && pm.ForSystem().Stats.InboundUplink {
+		statsManager := core.MustFromContext(ctx).GetFeature(stats.ManagerType()).(stats.Manager)
+		name := "inbound>>>" + t.tag + ">>>traffic>>>uplink"
+		c, _ := stats.GetOrRegisterCounter(statsManager, name)
+		if c != nil {
+			t.uplinkCounter = c
+		}
+	}
+	if len(t.tag) > 0 && pm.ForSystem().Stats.InboundDownlink {
+		statsManager := core.MustFromContext(ctx).GetFeature(stats.ManagerType()).(stats.Manager)
+		name := "inbound>>>" + t.tag + ">>>traffic>>>downlink"
+		c, _ := stats.GetOrRegisterCounter(statsManager, name)
+		if c != nil {
+			t.downlinkCounter = c
+		}
+	}
+
 	return nil
 }
 
@@ -151,6 +171,14 @@ func (t *Handler) HandleConnection(conn net.Conn, destination net.Destination) {
 		return
 	}
 	source := net.DestinationFromAddr(remote)
+	if t.uplinkCounter != nil || t.downlinkCounter != nil {
+		conn = &stat.CounterConnection{
+			Connection:   conn,
+			ReadCounter:  t.uplinkCounter,
+			WriteCounter: t.downlinkCounter,
+		}
+	}
+
 	inbound := session.Inbound{
 		Name:          "tun",
 		Tag:           t.tag,