FlagLoopback                       // interface is a loopback interface
	FlagPointToPoint                   // interface belongs to a point-to-point link
	FlagMulticast                      // interface supports multicast access capability
	FlagRunning                        // interface is in running state
)

var flagNames = []string{
	"up",
	"broadcast",
	"loopback",
	"pointtopoint",
	"multicast",
	"running",
}

	// by iptables which were destined for nodeports on loopback interface.
	localhostNodePortsAcceptedPacketsDescription = metrics.NewDesc(
		"kubeproxy_iptables_localhost_nodeports_accepted_packets_total",
		"Number of packets accepted on nodeports of loopback interface",
		nil, nil, metrics.ALPHA, "")
	LocalhostNodePortAcceptedNFAcctCounter     = "localhost_nps_accepted_pkts"

			linkLocalUnicast: true,
		},
		{
			name:     "loopback v4Addr",
			ip:       loopback4,
			loopback: true,
		},
		{
			name:     "loopback v6Addr",
			ip:       IPv6Loopback(),
			loopback: true,
		},
		{
			name:     "loopback v6 mapped v4Addr",
			ip:       AddrFrom16(IPv6Loopback().As16()),
			loopback: true,
		},
		{

// if the loopback client config is specified AND it has a bearer token. Note that if either authn or
// authz is nil, this function won't add a token authenticator or authorizer.
func AuthorizeClientBearerToken(loopback *restclient.Config, authn *AuthenticationInfo, authz *AuthorizationInfo) {
	if loopback == nil || len(loopback.BearerToken) == 0 {
		return
	}

	}

	return ipList, err
}

// sortIPs - sort ips based on higher octets.
// The logic to sort by last octet is implemented to
// prefer CIDRs with higher octets, this in-turn skips the
// localhost/loopback address to be not preferred as the
// first ip on the list. Subsequently this list helps us print
// a user friendly message with appropriate values.
func sortIPs(ipList []string) []string {
	if len(ipList) == 1 {

	//    Default Gateway:                      10.0.0.254
	//    Gateway Metric:                       0
	//    InterfaceMetric:                      10
	//
	//Configuration for interface "Loopback Pseudo-Interface 1"
	//    DHCP enabled:                         No
	//    IP Address:                           127.0.0.1
	//    Subnet Prefix:                        127.0.0.0/8 (mask 255.0.0.0)

				if h, _, err := net.SplitHostPort(address); err == nil {
					address = h
				}
				// Create socket on specific vrf device.
				// To catch all kinds of special cases this filters specifically for loopback networks.
				if ip := net.ParseIP(address); ip != nil && !ip.IsLoopback() {
					_ = syscall.SetsockoptString(fd, syscall.SOL_SOCKET, syscall.SO_BINDTODEVICE, opts.Interface)
				}
			}
		})
		return nil
	}

	var tests = []struct {
		name           string
		check          HTTPProxyCheck
		expectWarnings bool
	}{
		{
			name: "Loopback address",
			check: HTTPProxyCheck{
				Proto: "https",
				Host:  "127.0.0.1",
			}, // Loopback addresses never should produce proxy warnings
			expectWarnings: false,
		},
		{
			name: "IPv4 direct access",
			check: HTTPProxyCheck{

127.0.0.1	localhost
::1	localhost ip6-localhost ip6-loopback
fe00::0	ip6-localnet
fe00::0	ip6-mcastprefix
fe00::1	ip6-allnodes
fe00::2	ip6-allrouters
123.45.67.89	some.domain
`,
			expectedHostsFileContent: `# Kubernetes-managed hosts file (host network).
# hosts file for testing.
127.0.0.1	localhost
::1	localhost ip6-localhost ip6-loopback
fe00::0	ip6-localnet
fe00::0	ip6-mcastprefix
fe00::1	ip6-allnodes

func hostResolveToLocalhost(endpoint Endpoint) bool {
	hostIPs, err := getHostIP(endpoint.Hostname())
	if err != nil {
		return false
	}
	var loopback int
	for _, hostIP := range hostIPs.ToSlice() {
		if net.ParseIP(hostIP).IsLoopback() {
			loopback++
		}
	}
	return loopback == len(hostIPs)
}

// UpdateIsLocal - resolves the host and discovers the local host.
func (endpoints Endpoints) UpdateIsLocal() error {