Use LinkIndex instead of Link obj in Route, Neigh

Having object composition causes both client and library to
do potentially unecessary work to retrieve Link attributes
when only index is often sufficient.

neigh.go

@@ -7,7 +7,7 @@ import (
 
 // Neigh represents a link layer neighbor from netlink.
 type Neigh struct {
-	Link         Link
+	LinkIndex    int
 	Family       int
 	State        int
 	Type         int

neigh_linux.go

@@ -104,7 +104,7 @@ func neighHandle(neigh *Neigh, req *nl.NetlinkRequest) error {
 
 	msg := Ndmsg{
 		Family: uint8(family),
-		Index:  uint32(neigh.Link.Attrs().Index),
+		Index:  uint32(neigh.LinkIndex),
 		State:  uint16(neigh.State),
 		Type:   uint8(neigh.Type),
 		Flags:  uint8(neigh.Flags),
@@ -163,17 +163,12 @@ func NeighList(linkIndex, family int) ([]Neigh, error) {
 func NeighDeserialize(m []byte) (*Neigh, error) {
 	msg := deserializeNdmsg(m)
 
-	link, err := LinkByIndex(int(msg.Index))
-	if err != nil {
-		return nil, err
-	}
-
 	neigh := Neigh{
-		Family: int(msg.Family),
-		State:  int(msg.State),
-		Type:   int(msg.Type),
-		Flags:  int(msg.Flags),
-		Link:   link,
+		LinkIndex: int(msg.Index),
+		Family:    int(msg.Family),
+		State:     int(msg.State),
+		Type:      int(msg.Type),
+		Flags:     int(msg.Flags),
 	}
 
 

neigh_test.go

@@ -46,7 +46,7 @@ func TestNeighAddDel(t *testing.T) {
 	// Add the arpTable
 	for _, entry := range arpTable {
 		err := NeighAdd(&Neigh{
-			Link:         &dummy,
+			LinkIndex:    dummy.Index,
 			State:        NUD_REACHABLE,
 			IP:           entry.ip,
 			HardwareAddr: entry.mac,
@@ -74,7 +74,7 @@ func TestNeighAddDel(t *testing.T) {
 	// Delete the arpTable
 	for _, entry := range arpTable {
 		err := NeighDel(&Neigh{
-			Link:         &dummy,
+			LinkIndex:    dummy.Index,
 			IP:           entry.ip,
 			HardwareAddr: entry.mac,
 		})

route.go

@@ -22,15 +22,14 @@ const (
 // gateway. Advanced route parameters and non-main routing tables are
 // currently not supported.
 type Route struct {
-	Link  Link
-	Scope Scope
-	Dst   *net.IPNet
-	Src   net.IP
-	Gw    net.IP
+	LinkIndex int
+	Scope     Scope
+	Dst       *net.IPNet
+	Src       net.IP
+	Gw        net.IP
 }
 
 func (r Route) String() string {
-	base := r.Link.Attrs()
-	return fmt.Sprintf("{%s Dst: %s Src: %s Gw: %s}", base.Name, r.Dst.String(),
+	return fmt.Sprintf("{Ifindex: %d Dst: %s Src: %s Gw: %s}", r.LinkIndex, r.Dst.String(),
 		r.Src, r.Gw)
 }

route_linux.go

@@ -90,8 +90,7 @@ func routeHandle(route *Route, req *nl.NetlinkRequest) error {
 		b      = make([]byte, 4)
 		native = nl.NativeEndian()
 	)
-	base := route.Link.Attrs()
-	native.PutUint32(b, uint32(base.Index))
+	native.PutUint32(b, uint32(route.LinkIndex))
 
 	req.AddData(nl.NewRtAttr(syscall.RTA_OIF, b))
 
@@ -157,8 +156,7 @@ func RouteList(link Link, family int) ([]Route, error) {
 					// Ignore routes from other interfaces
 					continue
 				}
-				resLink, _ := LinkByIndex(routeIndex)
-				route.Link = resLink
+				route.LinkIndex = routeIndex
 			}
 		}
 		res = append(res, route)

route_test.go

@@ -24,7 +24,7 @@ func TestRouteAddDel(t *testing.T) {
 	_, dst, err := net.ParseCIDR("192.168.0.0/24")
 
 	ip := net.ParseIP("127.1.1.1")
-	route := Route{Link: link, Dst: dst, Src: ip}
+	route := Route{LinkIndex: link.Attrs().Index, Dst: dst, Src: ip}
 	err = RouteAdd(&route)
 	if err != nil {
 		t.Fatal(err)