feat: impelmentation of vrf

clean.sh

@@ -18,3 +18,11 @@ for XFRMI in ${XFRMIs}; do
     sudo ip link del ${XFRMI}
     echo del ${XFRMI}
 done
+
+# Remove all VRF interfaces
+echo "[Info] Remove all VRF interfaces"
+VRFs=$(ip link show type vrf | awk 'NR%2==1 {print $2}' | cut -d @ -f 1)
+for VRF in ${VRFs}; do
+    sudo ip link del ${VRF}
+    echo del ${VRF}
+done

go.mod

@@ -13,7 +13,6 @@ require (
 	github.com/free5gc/ngap v1.1.2
 	github.com/free5gc/openapi v1.2.3
 	github.com/free5gc/util v1.0.7-0.20241017071924-da29aef99a1c
-	github.com/go-ping/ping v0.0.0-20211014180314-6e2b003bffdd
 	github.com/google/gopacket v1.1.19
 	github.com/pkg/errors v0.9.1
 	github.com/sirupsen/logrus v1.9.3

internal/nwucp/handler.go

@@ -9,6 +9,7 @@ import (
 	"github.com/free5gc/n3iwue/internal/gre"
 	"github.com/free5gc/n3iwue/internal/logger"
 	"github.com/free5gc/n3iwue/internal/packet/nasPacket"
+	"github.com/free5gc/n3iwue/internal/vrf"
 	context "github.com/free5gc/n3iwue/pkg/context"
 	"github.com/free5gc/nas"
 	"github.com/free5gc/nas/nasType"
@@ -87,6 +88,17 @@ func (s *Server) handleDLNASTransport(evt *context.HandleDLNASTransportEvt) {
 
 		newGREName := fmt.Sprintf("%s-id-%d", n3ueSelf.N3ueInfo.GreIfaceName, n3ueSelf.N3ueInfo.XfrmiId)
 
+		// Create VRF
+		vrfName := fmt.Sprintf("vrf-pdu-%d", n3ueSelf.PduSessionCount)
+		vrfTableID := 100 + int(n3ueSelf.PduSessionCount)
+
+		vrfLink, err := vrf.CreateOrGetVRF(vrfName, vrfTableID)
+		if err != nil {
+			nwucpLog.Errorf("Create VRF failed:%s: %v", vrfName, err)
+			return
+		}
+		nwucpLog.Infof("Use VRF %s (Table %d)", vrfName, vrfTableID)
+
 		var linkGREs map[uint8]*netlink.Link
 		if linkGREs, err = gre.SetupGreTunnels(newGREName, n3ueSelf.TemporaryXfrmiName, n3ueSelf.UEInnerAddr.IP,
 			n3ueSelf.TemporaryUPIPAddr, pduAddress, n3ueSelf.TemporaryQosInfo); err != nil {
@@ -115,6 +127,12 @@ func (s *Server) handleDLNASTransport(evt *context.HandleDLNASTransportEvt) {
 				nwucpLog.Errorf("not found target address for QFI [%v] from NAS", qfi)
 				continue
 			}
+			// Bind GRE interface to VRF
+			if err := netlink.LinkSetMaster(tunnel, vrfLink); err != nil {
+				nwucpLog.Errorf("Failed to bind %s to VRF %s", tunnel.Attrs().Name, vrfName)
+				continue
+			}
+			nwucpLog.Infof("Interface %s bound to VRF %s", tunnel.Attrs().Name, vrfName)
 
 			nwucpLog.Infof("Add route: QFI[%+v] remote address[%+v]", qfi, remoteAddress)
 			upRoute := &netlink.Route{
@@ -124,6 +142,7 @@ func (s *Server) handleDLNASTransport(evt *context.HandleDLNASTransportEvt) {
 					Mask: remoteAddress.Mask,
 				},
 				Priority: priority,
+				Table:    vrfTableID,
 			}
 			if err := netlink.RouteAdd(upRoute); err != nil {
 				nwucpLog.Warnf("netlink.RouteAdd: %+v", err)

internal/vrf/vrf.go

@@ -0,0 +1,46 @@
+package vrf
+
+import (
+	"fmt"
+
+	"github.com/vishvananda/netlink"
+
+	"github.com/free5gc/n3iwue/pkg/context"
+)
+
+func CreateOrGetVRF(vrfName string, tableID int) (netlink.Link, error) {
+	// Try to get VRF
+	link, err := netlink.LinkByName(vrfName)
+	if err == nil {
+		// Found, check if it is a VRF
+		if vrf, ok := link.(*netlink.Vrf); ok {
+			if vrf.Table == uint32(tableID) {
+				return vrf, nil // VRF exists and is correct
+			}
+			return nil, fmt.Errorf("VRF %s exists but Table ID mismatch (need %d, actual %d)", vrfName, tableID, vrf.Table)
+		}
+		return nil, fmt.Errorf("device %s exists but is not a VRF", vrfName)
+	}
+
+	// Create VRF (l3mdev) device
+	vrfLink := &netlink.Vrf{
+		LinkAttrs: netlink.LinkAttrs{Name: vrfName},
+		Table:     uint32(tableID),
+	}
+
+	if err := netlink.LinkAdd(vrfLink); err != nil {
+		return nil, fmt.Errorf("netlink.LinkAdd VRF %s failed: %v", vrfName, err)
+	}
+
+	// Enable VRF device
+	if err := netlink.LinkSetUp(vrfLink); err != nil {
+		return nil, fmt.Errorf("netlink.LinkSetUp VRF %s failed: %v", vrfName, err)
+	}
+
+	// Add to CreatedIface for auto cleanup
+	n3ueSelf := context.N3UESelf()
+	var createdLink netlink.Link = vrfLink
+	n3ueSelf.CreatedIface = append(n3ueSelf.CreatedIface, &createdLink)
+
+	return vrfLink, nil
+}

pkg/procedure/Procedure.go

@@ -3,11 +3,10 @@ package procedure
 import (
 	"context"
 	"fmt"
+	"os/exec"
 	"runtime/debug"
 	"sync"
-	"time"
 
-	"github.com/go-ping/ping"
 	"github.com/sirupsen/logrus"
 
 	"github.com/free5gc/n3iwue/internal/logger"
@@ -127,46 +126,29 @@ func (s *Server) handleEvent(evt n3iwue_context.ProcedureEvt) {
 func (s *Server) TestConnectivity(addr string) error {
 	n3ueSelf := s.Context()
 
-	// Ping remote
-	pinger, err := ping.NewPinger(addr)
-	if err != nil {
-		return err
-	}
-
-	// Run with root
-	pinger.SetPrivileged(true)
+	// Calculate the VRF ID used for the last session
+	// Since PduSessionCount is incremented after session establishment, we subtract 1
+	vrfID := n3ueSelf.PduSessionCount - 1
+	vrfName := fmt.Sprintf("vrf-pdu-%d", vrfID)
 
-	pinger.OnRecv = func(pkt *ping.Packet) {
-		AppLog.Infof("%d bytes from %s: icmp_seq=%d time=%v\n",
-			pkt.Nbytes, pkt.IPAddr, pkt.Seq, pkt.Rtt)
-	}
-	pinger.OnFinish = func(stats *ping.Statistics) {
-		AppLog.Infof("\n--- %s ping statistics ---\n", stats.Addr)
-		AppLog.Infof("%d packets transmitted, %d packets received, %v%% packet loss\n",
-			stats.PacketsSent, stats.PacketsRecv, stats.PacketLoss)
-		AppLog.Infof("round-trip min/avg/max/stddev = %v/%v/%v/%v\n",
-			stats.MinRtt, stats.AvgRtt, stats.MaxRtt, stats.StdDevRtt)
-	}
+	AppLog.Infof("Ping %s using VRF %s", addr, vrfName)
 
-	pinger.Count = 5
-	pinger.Timeout = 10 * time.Second
+	args := []string{"vrf", "exec", vrfName, "ping", "-c", "5"}
 	if n3ueSelf.N3ueInfo.DnIPAddr != "" {
-		pinger.Source = n3ueSelf.N3ueInfo.DnIPAddr
+		args = append(args, "-I", n3ueSelf.N3ueInfo.DnIPAddr)
 	}
+	args = append(args, addr)
 
-	time.Sleep(3 * time.Second)
+	// Use ip vrf exec to ping
+	cmd := exec.CommandContext(context.Background(), "ip", args...)
 
-	if err := pinger.Run(); err != nil {
-		return fmt.Errorf("running ping failed: %+v", err)
-	}
-
-	time.Sleep(1 * time.Second)
-
-	stats := pinger.Statistics()
-	if stats.PacketsSent != stats.PacketsRecv {
-		return fmt.Errorf("ping failed")
+	// We can capture output to log it
+	output, err := cmd.CombinedOutput()
+	if err != nil {
+		return fmt.Errorf("ping failed: %v, output: %s", err, string(output))
 	}
 
+	AppLog.Infof("Ping output:\n%s", string(output))
 	return nil
 }