package osl import ( "bytes" "fmt" "net" "github.com/vishvananda/netlink" ) // NeighOption is a function option type to set interface options type NeighOption func(nh *neigh) type neigh struct { dstIP net.IP dstMac net.HardwareAddr linkName string linkDst string family int } func (n *networkNamespace) findNeighbor(dstIP net.IP, dstMac net.HardwareAddr) *neigh { n.Lock() defer n.Unlock() for _, nh := range n.neighbors { if nh.dstIP.Equal(dstIP) && bytes.Equal(nh.dstMac, dstMac) { return nh } } return nil } func (n *networkNamespace) DeleteNeighbor(dstIP net.IP, dstMac net.HardwareAddr) error { nh := n.findNeighbor(dstIP, dstMac) if nh == nil { return fmt.Errorf("could not find the neighbor entry to delete") } return nsInvoke(n.nsPath(), func(nsFD int) error { return nil }, func(callerFD int) error { var iface netlink.Link if nh.linkDst != "" { var err error iface, err = netlink.LinkByName(nh.linkDst) if err != nil { return fmt.Errorf("could not find interface with destination name %s: %v", nh.linkDst, err) } } nlnh := &netlink.Neigh{ IP: dstIP, State: netlink.NUD_PERMANENT, Family: nh.family, } if nlnh.Family > 0 { nlnh.HardwareAddr = dstMac nlnh.Flags = netlink.NTF_SELF } if nh.linkDst != "" { nlnh.LinkIndex = iface.Attrs().Index } if err := netlink.NeighDel(nlnh); err != nil { return fmt.Errorf("could not delete neighbor entry: %v", err) } for i, nh := range n.neighbors { if nh.dstIP.Equal(dstIP) && bytes.Equal(nh.dstMac, dstMac) { n.neighbors = append(n.neighbors[:i], n.neighbors[i+1:]...) } } return nil }) } func (n *networkNamespace) AddNeighbor(dstIP net.IP, dstMac net.HardwareAddr, options ...NeighOption) error { nh := n.findNeighbor(dstIP, dstMac) if nh != nil { // If it exists silently return return nil } nh = &neigh{ dstIP: dstIP, dstMac: dstMac, } nh.processNeighOptions(options...) if nh.linkName != "" { nh.linkDst = n.findDst(nh.linkName, false) if nh.linkDst == "" { return fmt.Errorf("could not find the interface with name %s", nh.linkName) } } return nsInvoke(n.nsPath(), func(nsFD int) error { return nil }, func(callerFD int) error { var iface netlink.Link if nh.linkDst != "" { var err error iface, err = netlink.LinkByName(nh.linkDst) if err != nil { return fmt.Errorf("could not find interface with destination name %s: %v", nh.linkDst, err) } } nlnh := &netlink.Neigh{ IP: dstIP, HardwareAddr: dstMac, State: netlink.NUD_PERMANENT, Family: nh.family, } if nlnh.Family > 0 { nlnh.Flags = netlink.NTF_SELF } if nh.linkDst != "" { nlnh.LinkIndex = iface.Attrs().Index } if err := netlink.NeighSet(nlnh); err != nil { return fmt.Errorf("could not add neighbor entry: %v", err) } n.neighbors = append(n.neighbors, nh) return nil }) }