func setupBridgeIPv6(config *networkConfiguration, i *bridgeInterface) error {
	procFile := "/proc/sys/net/ipv6/conf/" + config.BridgeName + "/disable_ipv6"
	ipv6BridgeData, err := ioutil.ReadFile(procFile)
	if err != nil {
		return fmt.Errorf("Cannot read IPv6 setup for bridge %v: %v", config.BridgeName, err)
	}
	// Enable IPv6 on the bridge only if it isn't already enabled
	if ipv6BridgeData[0] != '0' {
		if err := ioutil.WriteFile(procFile, []byte{'0', '\n'}, ipv6ForwardConfPerm); err != nil {
			return fmt.Errorf("Unable to enable IPv6 addresses on bridge: %v", err)
		}
	}

	_, addrsv6, err := i.addresses()
	if err != nil {
		return err
	}

	// Add the default link local ipv6 address if it doesn't exist
	if !findIPv6Address(netlink.Addr{IPNet: bridgeIPv6}, addrsv6) {
		if err := netlink.AddrAdd(i.Link, &netlink.Addr{IPNet: bridgeIPv6}); err != nil {
			return &IPv6AddrAddError{IP: bridgeIPv6, Err: err}
		}
	}

	// Store bridge network and default gateway
	i.bridgeIPv6 = bridgeIPv6
	i.gatewayIPv6 = i.bridgeIPv6.IP

	if config.AddressIPv6 == nil {
		return nil
	}

	// Store and program user specified bridge network and network gateway
	i.bridgeIPv6 = config.AddressIPv6
	i.gatewayIPv6 = config.AddressIPv6.IP
	if err := netlink.AddrAdd(i.Link, &netlink.Addr{IPNet: i.bridgeIPv6}); err != nil {
		return &IPv6AddrAddError{IP: i.bridgeIPv6, Err: err}
	}

	// Setting route to global IPv6 subnet
	logrus.Debugf("Adding route to IPv6 network %s via device %s", config.AddressIPv6.String(), config.BridgeName)
	err = netlink.RouteAdd(&netlink.Route{
		Scope:     netlink.SCOPE_UNIVERSE,
		LinkIndex: i.Link.Attrs().Index,
		Dst:       config.AddressIPv6,
	})
	if err != nil && !os.IsExist(err) {
		logrus.Errorf("Could not add route to IPv6 network %s via device %s", config.AddressIPv6.String(), config.BridgeName)
	}

	return nil
}

func createDummyInterface(t *testing.T) {
	if testutils.RunningOnCircleCI() {
		t.Skipf("Skipping as not supported on CIRCLE CI kernel")
	}

	dummy := &netlink.Dummy{
		LinkAttrs: netlink.LinkAttrs{
			Name: "dummy",
		},
	}

	err := netlink.LinkAdd(dummy)
	require.NoError(t, err)

	dummyLink, err := netlink.LinkByName("dummy")
	require.NoError(t, err)

	ip, ipNet, err := net.ParseCIDR("10.1.1.1/24")
	require.NoError(t, err)

	ipNet.IP = ip

	ipAddr := &netlink.Addr{IPNet: ipNet, Label: ""}
	err = netlink.AddrAdd(dummyLink, ipAddr)
	require.NoError(t, err)
}

// sets IP4 addr on link removing any existing ones first
func setAddr4(link *netlink.Vxlan, ipn *net.IPNet) error {
	addrs, err := netlink.AddrList(link, syscall.AF_INET)
	if err != nil {
		return err
	}

	addr := netlink.Addr{ipn, ""}
	existing := false
	for _, old := range addrs {
		if old.IPNet.String() == addr.IPNet.String() {
			existing = true
			continue
		}
		if err = netlink.AddrDel(link, &old); err != nil {
			return fmt.Errorf("failed to delete IPv4 addr %s from %s", old.String(), link.Attrs().Name)
		}
	}

	if !existing {
		if err = netlink.AddrAdd(link, &addr); err != nil {
			return fmt.Errorf("failed to add IP address %s to %s: %s", ipn.String(), link.Attrs().Name, err)
		}
	}

	return nil
}

// ConfigureIface takes the result of IPAM plugin and
// applies to the ifName interface
func configureIface(conf *NetConf) error {
	ifName := conf.IfName
	link, err := netlink.LinkByName(ifName)
	if err != nil {
		return fmt.Errorf("failed to lookup %q: %v", ifName, err)
	}

	if err := netlink.LinkSetUp(link); err != nil {
		return fmt.Errorf("failed to set %q UP: %v", ifName, err)
	}

	i, n, err := net.ParseCIDR(conf.IPAddr)
	if err != nil {
		return fmt.Errorf("failed to parse ip address :%s", conf.IPAddr)
	}

	addr := &net.IPNet{IP: i, Mask: n.Mask}
	nlAddr := &netlink.Addr{IPNet: addr, Label: ""}
	if err = netlink.AddrAdd(link, nlAddr); err != nil {
		return fmt.Errorf("failed to add IP addr to %q: %v", ifName, err)
	}

	gw := net.ParseIP(conf.Gateway)
	if gw == nil {
		return fmt.Errorf("parse gateway: %s return nil", conf.Gateway)
	}

	if err = ip.AddDefaultRoute(gw, link); err != nil {
		// we skip over duplicate routes as we assume the first one wins
		if !os.IsExist(err) {
			return fmt.Errorf("failed to add default route via %v dev %v: %v", gw, ifName, err)
		}
	}
	return nil
}

/*   SetupNetwork()
 */
func SetupNetwork(addr string) error {
	// Bring up loop back interface.
	lo, e := netlink.LinkByName("lo")
	if e != nil {
		return fmt.Errorf("Failed to find loopback interface: %v", e)
	}

	if e := netlink.LinkSetUp(lo); e != nil {
		return fmt.Errorf("Failed to setup loopback interface: %v", e)
	}

	if len(addr) > 0 {
		veth, e := netlink.LinkByName("veth0")
		if e != nil {
			return fmt.Errorf("Failed to find veth interface: %v", e)
		}

		addr, e := netlink.ParseAddr(addr)
		if e != nil {
			return fmt.Errorf("Failed to parse NetworkAddr: %v", e)
		}

		netlink.AddrAdd(veth, addr)
		if e := netlink.LinkSetUp(veth); e != nil {
			return fmt.Errorf("Network link failed to come up: %v", e)
		}
	}

	return nil
}

func IpAddrAdd(cResp chan<- *Response, rawArgs *json.RawMessage, tag string) {
	args := &struct {
		Ifname string `json:"ifname"`
		IpCidr string `json:"ip"`
	}{}

	json.Unmarshal(*rawArgs, &args)

	iface, err := netlink.LinkByName(args.Ifname)
	if err != nil {
		cResp <- &Response{nil, tag, NewRTNetlinkError(err)}
		return
	}

	ip, err := netlink.ParseAddr(args.IpCidr)
	if err != nil {
		cResp <- &Response{nil, tag, NewRTNetlinkError(err)}
		return
	}

	if err := netlink.AddrAdd(iface, ip); err != nil {
		cResp <- &Response{nil, tag, NewRTNetlinkError(err)}
		return
	}

	cResp <- &Response{true, tag, nil}
}

func setInterfaceIPv6(iface netlink.Link, settings *Interface) error {
	if settings.AddressIPv6 == nil {
		return nil
	}
	ipAddr := &netlink.Addr{IPNet: settings.AddressIPv6, Label: ""}
	return netlink.AddrAdd(iface, ipAddr)
}

func addIPConfigToLink(ipConfig *ipam.IPConfig, link netlink.Link, ifName string) error {
	log.Debugf("Configuring link %+v/%s with %+v", link, ifName, ipConfig)

	addr := &netlink.Addr{IPNet: &ipConfig.IP}
	if err := netlink.AddrAdd(link, addr); err != nil {
		return fmt.Errorf("failed to add addr to %q: %v", ifName, err)
	}

	// Sort provided routes to make sure we apply any more specific
	// routes first which may be used as nexthops in wider routes
	sort.Sort(ipam.ByMask(ipConfig.Routes))

	for _, r := range ipConfig.Routes {
		log.Debugf("Adding route %+v", r)
		rt := &netlink.Route{
			LinkIndex: link.Attrs().Index,
			Scope:     netlink.SCOPE_UNIVERSE,
			Dst:       &r.Destination,
			Gw:        r.NextHop,
		}

		if r.IsL2() {
			rt.Scope = netlink.SCOPE_LINK
		}

		if err := netlink.RouteAdd(rt); err != nil {
			if !os.IsExist(err) {
				return fmt.Errorf("failed to add route '%s via %v dev %v': %v",
					r.Destination.String(), r.NextHop, ifName, err)
			}
		}
	}

	return nil
}

func setupHostVeth(vethName string, ipConf *types.IPConfig) error {
	// hostVeth moved namespaces and may have a new ifindex
	veth, err := netlink.LinkByName(vethName)
	if err != nil {
		return fmt.Errorf("failed to lookup %q: %v", vethName, err)
	}

	// TODO(eyakubovich): IPv6
	ipn := &net.IPNet{
		IP:   ipConf.Gateway,
		Mask: net.CIDRMask(32, 32),
	}
	addr := &netlink.Addr{IPNet: ipn, Label: ""}
	if err = netlink.AddrAdd(veth, addr); err != nil {
		return fmt.Errorf("failed to add IP addr (%#v) to veth: %v", ipn, err)
	}

	ipn = &net.IPNet{
		IP:   ipConf.IP.IP,
		Mask: net.CIDRMask(32, 32),
	}
	// dst happens to be the same as IP/net of host veth
	if err = ip.AddHostRoute(ipn, nil, veth); err != nil && !os.IsExist(err) {
		return fmt.Errorf("failed to add route on host: %v", err)
	}

	return nil
}

func setInterfaceIPv6(iface netlink.Link, i *nwIface) error {
	if i.AddressIPv6() == nil {
		return nil
	}
	ipAddr := &netlink.Addr{IPNet: i.AddressIPv6(), Label: "", Flags: syscall.IFA_F_NODAD}
	return netlink.AddrAdd(iface, ipAddr)
}

func configureIface(ifname string, ipn ip.IP4Net, mtu int) error {
	iface, err := netlink.LinkByName(ifname)
	if err != nil {
		return fmt.Errorf("failed to lookup interface %v", ifname)
	}

	err = netlink.AddrAdd(iface, &netlink.Addr{IPNet: ipn.ToIPNet(), Label: ""})
	if err != nil {
		return fmt.Errorf("failed to add IP address %v to %v: %v", ipn.String(), ifname, err)
	}

	err = netlink.LinkSetMTU(iface, mtu)
	if err != nil {
		return fmt.Errorf("failed to set MTU for %v: %v", ifname, err)
	}

	err = netlink.LinkSetUp(iface)
	if err != nil {
		return fmt.Errorf("failed to set interface %v to UP state: %v", ifname, err)
	}

	// explicitly add a route since there might be a route for a subnet already
	// installed by Docker and then it won't get auto added
	err = netlink.RouteAdd(&netlink.Route{
		LinkIndex: iface.Attrs().Index,
		Scope:     netlink.SCOPE_UNIVERSE,
		Dst:       ipn.Network().ToIPNet(),
	})
	if err != nil && err != syscall.EEXIST {
		return fmt.Errorf("failed to add route (%v -> %v): %v", ipn.Network().String(), ifname, err)
	}

	return nil
}

// ConfigureIface takes the result of IPAM plugin and
// applies to the ifName interface
func ConfigureIface(ifName string, res *types.Result) error {
	link, err := netlink.LinkByName(ifName)
	if err != nil {
		return fmt.Errorf("failed to lookup %q: %v", ifName, err)
	}

	if err := netlink.LinkSetUp(link); err != nil {
		return fmt.Errorf("failed to set %q UP: %v", ifName, err)
	}

	// TODO(eyakubovich): IPv6
	addr := &netlink.Addr{IPNet: &res.IP4.IP, Label: ""}
	if err = netlink.AddrAdd(link, addr); err != nil {
		return fmt.Errorf("failed to add IP addr to %q: %v", ifName, err)
	}

	for _, r := range res.IP4.Routes {
		gw := r.GW
		if gw == nil {
			gw = res.IP4.Gateway
		}
		if err = ip.AddRoute(&r.Dst, gw, link); err != nil {
			// we skip over duplicate routes as we assume the first one wins
			if !os.IsExist(err) {
				return fmt.Errorf("failed to add route '%v via %v dev %v': %v", r.Dst, gw, ifName, err)
			}
		}
	}

	return nil
}

func main() {
	lo, _ := netlink.LinkByName("lo")
	fmt.Println(lo)
	addr, _ := netlink.ParseAddr("127.0.0.2/8")
	fmt.Println(addr)
	netlink.AddrAdd(lo, addr)
	fmt.Println(netlink.AddrList(lo, netlink.FAMILY_ALL))

	req := nl.NewNetlinkRequest(syscall.NLMSG_MIN_TYPE, syscall.NLM_F_REQUEST)

	data := append([]byte("TASKSTATS"), 0)
	a := &Attr{
		Type: 2,
		Data: data,
	}
	Hdr := []byte{
		3,
		0,
		0,
		0,
	}
	m := &Message{
		Type:    16,
		Pid:     -1,
		Seq:     -1,
		Flags:   NLM_F_REQUEST,
		Payload: append(Hdr, a.Dump()...),
	}

	req.AddData(m)
	res, _ := req.Execute(syscall.NETLINK_GENERIC, 0)
	fmt.Println(res)
	fmt.Println(parse_attributes(res[0][4:])[1])
}

func createInterface(t *testing.T, name string, nws ...string) {
	// Add interface
	link := &netlink.Bridge{
		LinkAttrs: netlink.LinkAttrs{
			Name: "test",
		},
	}
	bips := []*net.IPNet{}
	for _, nw := range nws {
		bip, err := types.ParseCIDR(nw)
		if err != nil {
			t.Fatal(err)
		}
		bips = append(bips, bip)
	}
	if err := netlink.LinkAdd(link); err != nil {
		t.Fatalf("Failed to create interface via netlink: %v", err)
	}
	for _, bip := range bips {
		if err := netlink.AddrAdd(link, &netlink.Addr{IPNet: bip}); err != nil {
			t.Fatal(err)
		}
	}
	if err := netlink.LinkSetUp(link); err != nil {
		t.Fatal(err)
	}
}

// Create creates a bridge device and returns the interface.
// If the device already exists, returns the existing interface.
func (Bridge) Create(name string, ip net.IP, subnet *net.IPNet) (intf *net.Interface, err error) {
	netlinkMu.Lock()
	defer netlinkMu.Unlock()

	if intf, _ := net.InterfaceByName(name); intf != nil {
		return intf, nil
	}

	link := &netlink.Bridge{LinkAttrs: netlink.LinkAttrs{Name: name}}

	if err := netlink.LinkAdd(link); err != nil && err.Error() != "file exists" {
		return nil, fmt.Errorf("devices: create bridge: %v", err)
	}

	hAddr, _ := net.ParseMAC(randMacAddr())
	err = netlink.LinkSetHardwareAddr(link, hAddr)
	if err != nil {
		return nil, fmt.Errorf("devices: set hardware address: %v", err)
	}

	if intf, err = net.InterfaceByName(name); err != nil {
		return nil, fmt.Errorf("devices: look up created bridge interface: %v", err)
	}

	addr := &netlink.Addr{IPNet: &net.IPNet{IP: ip, Mask: subnet.Mask}}
	if err = netlink.AddrAdd(link, addr); err != nil && err.Error() != "file exists" {
		return nil, fmt.Errorf("devices: add IP to bridge: %v", err)
	}
	return intf, nil
}

func setupBridgeIPv6(config *networkConfiguration, i *bridgeInterface) error {
	// Enable IPv6 on the bridge
	procFile := "/proc/sys/net/ipv6/conf/" + config.BridgeName + "/disable_ipv6"
	if err := ioutil.WriteFile(procFile, []byte{'0', '\n'}, ipv6ForwardConfPerm); err != nil {
		return fmt.Errorf("Unable to enable IPv6 addresses on bridge: %v", err)
	}

	_, addrsv6, err := i.addresses()
	if err != nil {
		return err
	}

	// Add the default link local ipv6 address if it doesn't exist
	if !findIPv6Address(netlink.Addr{IPNet: bridgeIPv6}, addrsv6) {
		if err := netlink.AddrAdd(i.Link, &netlink.Addr{IPNet: bridgeIPv6}); err != nil {
			return &IPv6AddrAddError{IP: bridgeIPv6, Err: err}
		}
	}

	// Store bridge network and default gateway
	i.bridgeIPv6 = bridgeIPv6
	i.gatewayIPv6 = i.bridgeIPv6.IP

	return nil
}

func routingUp() {
	veth, err := netlink.LinkByName("myveth1")
	if err != nil {
		panic(err)
	}

	err = netlink.LinkSetUp(veth)
	if err != nil {
		panic(err)
	}

	addr, _ := netlink.ParseAddr("172.19.80.2/24")
	err = netlink.AddrAdd(veth, addr)
	if err != nil {
		panic(err)
	}

	routes := createRoutes(veth)

	for _, route := range routes {
		fmt.Println("Adding route", route)
		err := netlink.RouteAdd(route)
		if err != nil {
			fmt.Println(err)
			// panic(err)
		}
	}
}

func applyNetConf(link netlink.Link, netConf config.InterfaceConfig) error {
	if netConf.DHCP {
		log.Infof("Running DHCP on %s", link.Attrs().Name)
		cmd := exec.Command("dhcpcd", "-A4", "-e", "force_hostname=true", link.Attrs().Name)
		cmd.Stdout = os.Stdout
		cmd.Stderr = os.Stderr
		if err := cmd.Run(); err != nil {
			log.Error(err)
		}
	} else if netConf.IPV4LL {
		if err := AssignLinkLocalIP(link); err != nil {
			log.Error("IPV4LL set failed")
			return err
		}
	} else if netConf.Address == "" {
		return nil
	} else {
		addr, err := netlink.ParseAddr(netConf.Address)
		if err != nil {
			return err
		}
		if err := netlink.AddrAdd(link, addr); err != nil {
			log.Error("addr add failed")
			return err
		}
		log.Infof("Set %s on %s", netConf.Address, link.Attrs().Name)
	}

	if netConf.MTU > 0 {
		if err := netlink.LinkSetMTU(link, netConf.MTU); err != nil {
			log.Error("set MTU Failed")
			return err
		}
	}

	if err := netlink.LinkSetUp(link); err != nil {
		log.Error("failed to setup link")
		return err
	}

	if netConf.Gateway != "" {
		gatewayIp := net.ParseIP(netConf.Gateway)
		if gatewayIp == nil {
			return errors.New("Invalid gateway address " + netConf.Gateway)
		}

		route := netlink.Route{
			Scope: netlink.SCOPE_UNIVERSE,
			Gw:    net.ParseIP(netConf.Gateway),
		}
		if err := netlink.RouteAdd(&route); err != nil {
			log.Error("gateway set failed")
			return err
		}

		log.Infof("Set default gateway %s", netConf.Gateway)
	}

	return nil
}

// Set the IP addr of a netlink interface
func (driver *driver) setInterfaceIP(name string, rawIP string) error {
	var netlinkRetryTimer time.Duration
	netlinkRetryTimer = 2
	iface, err := netlink.LinkByName(name)
	if err != nil {
		log.Debugf("error retrieving new OVS bridge netlink link [ %s ] allowing another [ %d ] seconds for the host to finish creating it..", bridgeName, netlinkRetryTimer)
		time.Sleep(netlinkRetryTimer * time.Second)
		iface, err = netlink.LinkByName(name)
		if err != nil {
			log.Debugf("error retrieving new OVS bridge netlink link [ %s ] allowing another [ %d ] seconds for the host to finish creating it..", bridgeName, netlinkRetryTimer)
			time.Sleep(netlinkRetryTimer * time.Second)
			iface, err = netlink.LinkByName(name)
			if err != nil {
				log.Fatalf("Abandoning retrieving the new OVS bridge link from netlink, Run [ ip link ] to troubleshoot the error: %s", err)
				return err
			}
		}
	}
	ipNet, err := netlink.ParseIPNet(rawIP)
	if err != nil {
		return err
	}
	addr := &netlink.Addr{ipNet, ""}
	return netlink.AddrAdd(iface, addr)
}

func setInterfaceIPv6(iface netlink.Link, i *nwIface) error {
	if i.AddressIPv6() == nil {
		return nil
	}
	ipAddr := &netlink.Addr{IPNet: i.AddressIPv6(), Label: ""}
	return netlink.AddrAdd(iface, ipAddr)
}