Update libnetwork vendor to current master to fix CI

Avoid a Sirupsen vs sirupsen class for logrus by updating to
master.

Signed-off-by: Matthew Heon <matthew.heon@gmail.com>

vendor/github.com/docker/libnetwork/netutils/utils_linux.go

@@ -4,24 +4,31 @@
 package netutils
 
 import (
+	"fmt"
 	"net"
 	"strings"
 
+	"github.com/docker/libnetwork/ipamutils"
+	"github.com/docker/libnetwork/ns"
+	"github.com/docker/libnetwork/osl"
+	"github.com/docker/libnetwork/resolvconf"
 	"github.com/docker/libnetwork/types"
 	"github.com/vishvananda/netlink"
 )
 
 var (
-	networkGetRoutesFct = netlink.RouteList
+	networkGetRoutesFct func(netlink.Link, int) ([]netlink.Route, error)
 )
 
 // CheckRouteOverlaps checks whether the passed network overlaps with any existing routes
 func CheckRouteOverlaps(toCheck *net.IPNet) error {
+	if networkGetRoutesFct == nil {
+		networkGetRoutesFct = ns.NlHandle().RouteList
+	}
 	networks, err := networkGetRoutesFct(nil, netlink.FAMILY_V4)
 	if err != nil {
 		return err
 	}
-
 	for _, network := range networks {
 		if network.Dst != nil && NetworkOverlaps(toCheck, network.Dst) {
 			return ErrNetworkOverlaps
@@ -33,13 +40,18 @@ func CheckRouteOverlaps(toCheck *net.IPNet) error {
 // GenerateIfaceName returns an interface name using the passed in
 // prefix and the length of random bytes. The api ensures that the
 // there are is no interface which exists with that name.
-func GenerateIfaceName(prefix string, len int) (string, error) {
+func GenerateIfaceName(nlh *netlink.Handle, prefix string, len int) (string, error) {
+	linkByName := netlink.LinkByName
+	if nlh != nil {
+		linkByName = nlh.LinkByName
+	}
 	for i := 0; i < 3; i++ {
 		name, err := GenerateRandomName(prefix, len)
 		if err != nil {
 			continue
 		}
-		if _, err := netlink.LinkByName(name); err != nil {
+		_, err = linkByName(name)
+		if err != nil {
 			if strings.Contains(err.Error(), "not found") {
 				return name, nil
 			}
@@ -48,3 +60,67 @@ func GenerateIfaceName(prefix string, len int) (string, error) {
 	}
 	return "", types.InternalErrorf("could not generate interface name")
 }
+
+// ElectInterfaceAddresses looks for an interface on the OS with the
+// specified name and returns returns all its IPv4 and IPv6 addresses in CIDR notation.
+// If a failure in retrieving the addresses or no IPv4 address is found, an error is returned.
+// If the interface does not exist, it chooses from a predefined
+// list the first IPv4 address which does not conflict with other
+// interfaces on the system.
+func ElectInterfaceAddresses(name string) ([]*net.IPNet, []*net.IPNet, error) {
+	var (
+		v4Nets []*net.IPNet
+		v6Nets []*net.IPNet
+	)
+
+	defer osl.InitOSContext()()
+
+	link, _ := ns.NlHandle().LinkByName(name)
+	if link != nil {
+		v4addr, err := ns.NlHandle().AddrList(link, netlink.FAMILY_V4)
+		if err != nil {
+			return nil, nil, err
+		}
+		v6addr, err := ns.NlHandle().AddrList(link, netlink.FAMILY_V6)
+		if err != nil {
+			return nil, nil, err
+		}
+		for _, nlAddr := range v4addr {
+			v4Nets = append(v4Nets, nlAddr.IPNet)
+		}
+		for _, nlAddr := range v6addr {
+			v6Nets = append(v6Nets, nlAddr.IPNet)
+		}
+	}
+
+	if link == nil || len(v4Nets) == 0 {
+		// Choose from predefined local scope  networks
+		v4Net, err := FindAvailableNetwork(ipamutils.PredefinedLocalScopeDefaultNetworks)
+		if err != nil {
+			return nil, nil, err
+		}
+		v4Nets = append(v4Nets, v4Net)
+	}
+
+	return v4Nets, v6Nets, nil
+}
+
+// FindAvailableNetwork returns a network from the passed list which does not
+// overlap with existing interfaces in the system
+func FindAvailableNetwork(list []*net.IPNet) (*net.IPNet, error) {
+	// We don't check for an error here, because we don't really care if we
+	// can't read /etc/resolv.conf. So instead we skip the append if resolvConf
+	// is nil. It either doesn't exist, or we can't read it for some reason.
+	var nameservers []string
+	if rc, err := resolvconf.Get(); err == nil {
+		nameservers = resolvconf.GetNameserversAsCIDR(rc.Content)
+	}
+	for _, nw := range list {
+		if err := CheckNameserverOverlaps(nameservers, nw); err == nil {
+			if err := CheckRouteOverlaps(nw); err == nil {
+				return nw, nil
+			}
+		}
+	}
+	return nil, fmt.Errorf("no available network")
+}