fea: support vrf for a network

pkg/network/vrf_linux.go

@@ -0,0 +1,111 @@
+package network
+
+import (
+	"github.com/luscis/openlan/pkg/libol"
+	"github.com/vishvananda/netlink"
+	nl "github.com/vishvananda/netlink"
+)
+
+type VRF struct {
+	name  string
+	table int
+	link  nl.Link
+	out   *libol.SubLogger
+}
+
+var tableId = 1000
+
+func GenTable() int {
+	tableId += 1
+	return tableId
+}
+
+func NewVRF(name string, table int) *VRF {
+	if table == 0 {
+		table = GenTable()
+	}
+	return &VRF{
+		name:  name,
+		table: table,
+		out:   libol.NewSubLogger(name),
+	}
+}
+
+func (v *VRF) Up() error {
+	if link, _ := nl.LinkByName(v.name); link != nil {
+		v.link = link
+		return nil
+	}
+
+	link := &nl.Vrf{
+		LinkAttrs: nl.LinkAttrs{
+			Name: v.name,
+		},
+		Table: uint32(v.table),
+	}
+
+	if err := nl.LinkAdd(link); err != nil {
+		return err
+	}
+	if err := nl.LinkSetUp(link); err != nil {
+		return err
+	}
+
+	v.link = link
+	v.out.Info("VRF.Up %s", v.name)
+
+	return nil
+}
+
+func (v *VRF) Down() error {
+	if v.link == nil {
+		return nil
+	}
+
+	if err := nl.LinkDel(v.link); err != nil {
+		return err
+	}
+
+	v.link = nil
+	v.out.Info("VRF.Down %s", v.name)
+
+	return nil
+}
+
+func (v *VRF) AddSlave(name string) error {
+	if v.link == nil {
+		return libol.NewErr("VRF %s not up", v.name)
+	}
+
+	link, err := netlink.LinkByName(name)
+	if link == nil {
+		return err
+	}
+
+	if err := nl.LinkSetMaster(link, v.link); err != nil {
+		return nil
+	}
+
+	v.out.Info("VRF.AddSlave %s", name)
+
+	return nil
+}
+
+func (v *VRF) DelSlave(name string) error {
+	link, _ := netlink.LinkByName(name)
+	if link == nil {
+		return nil
+	}
+
+	if err := nl.LinkSetNoMaster(link); err != nil {
+		return nil
+	}
+
+	v.out.Info("VRF.DelSlave %s", name)
+
+	return nil
+}
+
+func (v *VRF) Table() int {
+	return v.table
+}