Add support for Instances

pkg/cloudprovider/providers/cloudstack/cloudstack.go

@@ -20,11 +20,13 @@ import (
 	"errors"
 	"fmt"
 	"io"
+	"os"
+	"path/filepath"
 
 	"github.com/golang/glog"
+	"github.com/kardianos/osext"
 	"github.com/xanzy/go-cloudstack/cloudstack"
 	"gopkg.in/gcfg.v1"
-
 	"k8s.io/apimachinery/pkg/types"
 	"k8s.io/kubernetes/pkg/cloudprovider"
 	"k8s.io/kubernetes/pkg/controller"
@@ -48,6 +50,7 @@ type CSConfig struct {
 // CSCloud is an implementation of Interface for CloudStack.
 type CSCloud struct {
 	client    *cloudstack.CloudStackClient
+	metadata  *metadata
 	projectID string // If non-"", all resources will be created within this project
 	zone      string
 }
@@ -64,15 +67,14 @@ func init() {
 }
 
 func readConfig(config io.Reader) (*CSConfig, error) {
+	cfg := &CSConfig{}
+
 	if config == nil {
-		err := fmt.Errorf("no cloud provider config given")
-		return nil, err
+		return cfg, nil
 	}
 
-	cfg := &CSConfig{}
 	if err := gcfg.ReadInto(cfg, config); err != nil {
-		glog.Errorf("Couldn't parse config: %v", err)
-		return nil, err
+		return nil, fmt.Errorf("could not parse cloud provider config: %v", err)
 	}
 
 	return cfg, nil
@@ -80,9 +82,42 @@ func readConfig(config io.Reader) (*CSConfig, error) {
 
 // newCSCloud creates a new instance of CSCloud.
 func newCSCloud(cfg *CSConfig) (*CSCloud, error) {
-	client := cloudstack.NewAsyncClient(cfg.Global.APIURL, cfg.Global.APIKey, cfg.Global.SecretKey, !cfg.Global.SSLNoVerify)
+	cs := &CSCloud{
+		projectID: cfg.Global.ProjectID,
+		zone:      cfg.Global.Zone,
+	}
+
+	exe, err := osext.Executable()
+	if err != nil {
+		return nil, fmt.Errorf("cloud not find the service executable: %v", err)
+	}
 
-	return &CSCloud{client, cfg.Global.ProjectID, cfg.Global.Zone}, nil
+	// When running the kubelet service it's fine to not specify a config file (or only a
+	// partial config file) as all needed info can be retrieved anonymously using metadata.
+	if filepath.Base(exe) == "kubelet" || filepath.Base(exe) == "kubelet.exe" {
+		// In CloudStack your metadata is always served by the DHCP server.
+		dhcpServer, err := findDHCPServer()
+		if err == nil {
+			glog.V(4).Infof("Found metadata server: %v", dhcpServer)
+			cs.metadata = &metadata{dhcpServer: dhcpServer, zone: cs.zone}
+		} else {
+			glog.Errorf("Error searching metadata server: %v", err)
+		}
+	}
+
+	if cfg.Global.APIURL != "" && cfg.Global.APIKey != "" && cfg.Global.SecretKey != "" {
+		cs.client = cloudstack.NewAsyncClient(cfg.Global.APIURL, cfg.Global.APIKey, cfg.Global.SecretKey, !cfg.Global.SSLNoVerify)
+	}
+
+	if cs.client == nil {
+		if cs.metadata != nil {
+			glog.V(2).Infof("No API URL, key and secret are provided, so only using metadata!")
+		} else {
+			return nil, errors.New("no cloud provider config given")
+		}
+	}
+
+	return cs, nil
 }
 
 // Initialize passes a Kubernetes clientBuilder interface to the cloud provider
@@ -90,26 +125,54 @@ func (cs *CSCloud) Initialize(clientBuilder controller.ControllerClientBuilder)
 
 // LoadBalancer returns an implementation of LoadBalancer for CloudStack.
 func (cs *CSCloud) LoadBalancer() (cloudprovider.LoadBalancer, bool) {
+	if cs.client == nil {
+		return nil, false
+	}
+
 	return cs, true
 }
 
 // Instances returns an implementation of Instances for CloudStack.
 func (cs *CSCloud) Instances() (cloudprovider.Instances, bool) {
-	return nil, false
+	if cs.metadata != nil {
+		return cs.metadata, true
+	}
+
+	if cs.client == nil {
+		return nil, false
+	}
+
+	return cs, true
 }
 
 // Zones returns an implementation of Zones for CloudStack.
 func (cs *CSCloud) Zones() (cloudprovider.Zones, bool) {
+	if cs.metadata != nil {
+		return cs.metadata, true
+	}
+
+	if cs.client == nil {
+		return nil, false
+	}
+
 	return cs, true
 }
 
 // Clusters returns an implementation of Clusters for CloudStack.
 func (cs *CSCloud) Clusters() (cloudprovider.Clusters, bool) {
+	if cs.client == nil {
+		return nil, false
+	}
+
 	return nil, false
 }
 
 // Routes returns an implementation of Routes for CloudStack.
 func (cs *CSCloud) Routes() (cloudprovider.Routes, bool) {
+	if cs.client == nil {
+		return nil, false
+	}
+
 	return nil, false
 }
 
@@ -130,20 +193,72 @@ func (cs *CSCloud) HasClusterID() bool {
 
 // GetZone returns the Zone containing the region that the program is running in.
 func (cs *CSCloud) GetZone() (cloudprovider.Zone, error) {
+	zone := cloudprovider.Zone{}
+
+	if cs.zone == "" {
+		hostname, err := os.Hostname()
+		if err != nil {
+			return zone, fmt.Errorf("failed to get hostname for retrieving the zone: %v", err)
+		}
+
+		instance, count, err := cs.client.VirtualMachine.GetVirtualMachineByName(hostname)
+		if err != nil {
+			if count == 0 {
+				return zone, fmt.Errorf("could not find instance for retrieving the zone: %v", err)
+			}
+			return zone, fmt.Errorf("error getting instance for retrieving the zone: %v", err)
+		}
+
+		cs.zone = instance.Zonename
+	}
+
 	glog.V(2).Infof("Current zone is %v", cs.zone)
-	return cloudprovider.Zone{Region: cs.zone}, nil
+	zone.FailureDomain = cs.zone
+	zone.Region = cs.zone
+
+	return zone, nil
 }
 
-// GetZoneByProviderID implements Zones.GetZoneByProviderID
-// This is particularly useful in external cloud providers where the kubelet
-// does not initialize node data.
+// GetZoneByProviderID returns the Zone, found by using the provider ID.
 func (cs *CSCloud) GetZoneByProviderID(providerID string) (cloudprovider.Zone, error) {
-	return cloudprovider.Zone{}, errors.New("GetZoneByProviderID not implemented")
+	zone := cloudprovider.Zone{}
+
+	instance, count, err := cs.client.VirtualMachine.GetVirtualMachineByID(
+		providerID,
+		cloudstack.WithProject(cs.projectID),
+	)
+	if err != nil {
+		if count == 0 {
+			return zone, fmt.Errorf("could not find node by ID: %v", providerID)
+		}
+		return zone, fmt.Errorf("error retrieving zone: %v", err)
+	}
+
+	glog.V(2).Infof("Current zone is %v", cs.zone)
+	zone.FailureDomain = instance.Zonename
+	zone.Region = instance.Zonename
+
+	return zone, nil
 }
 
-// GetZoneByNodeName implements Zones.GetZoneByNodeName
-// This is particularly useful in external cloud providers where the kubelet
-// does not initialize node data.
+// GetZoneByNodeName returns the Zone, found by using the node name.
 func (cs *CSCloud) GetZoneByNodeName(nodeName types.NodeName) (cloudprovider.Zone, error) {
-	return cloudprovider.Zone{}, errors.New("GetZoneByNodeName not imeplemented")
+	zone := cloudprovider.Zone{}
+
+	instance, count, err := cs.client.VirtualMachine.GetVirtualMachineByName(
+		string(nodeName),
+		cloudstack.WithProject(cs.projectID),
+	)
+	if err != nil {
+		if count == 0 {
+			return zone, fmt.Errorf("could not find node: %v", nodeName)
+		}
+		return zone, fmt.Errorf("error retrieving zone: %v", err)
+	}
+
+	glog.V(2).Infof("Current zone is %v", cs.zone)
+	zone.FailureDomain = instance.Zonename
+	zone.Region = instance.Zonename
+
+	return zone, nil
 }

pkg/cloudprovider/providers/cloudstack/cloudstack_instances.go

+/*
+Copyright 2016 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package cloudstack
+
+import (
+	"errors"
+	"fmt"
+
+	"github.com/golang/glog"
+	"github.com/xanzy/go-cloudstack/cloudstack"
+	"k8s.io/api/core/v1"
+	"k8s.io/apimachinery/pkg/types"
+	"k8s.io/kubernetes/pkg/cloudprovider"
+)
+
+// NodeAddresses returns the addresses of the specified instance.
+func (cs *CSCloud) NodeAddresses(name types.NodeName) ([]v1.NodeAddress, error) {
+	instance, count, err := cs.client.VirtualMachine.GetVirtualMachineByName(
+		string(name),
+		cloudstack.WithProject(cs.projectID),
+	)
+	if err != nil {
+		if count == 0 {
+			return nil, cloudprovider.InstanceNotFound
+		}
+		return nil, fmt.Errorf("error retrieving node addresses: %v", err)
+	}
+
+	return cs.nodeAddresses(instance)
+}
+
+// NodeAddressesByProviderID returns the addresses of the specified instance.
+func (cs *CSCloud) NodeAddressesByProviderID(providerID string) ([]v1.NodeAddress, error) {
+	instance, count, err := cs.client.VirtualMachine.GetVirtualMachineByID(
+		providerID,
+		cloudstack.WithProject(cs.projectID),
+	)
+	if err != nil {
+		if count == 0 {
+			return nil, cloudprovider.InstanceNotFound
+		}
+		return nil, fmt.Errorf("error retrieving node addresses: %v", err)
+	}
+
+	return cs.nodeAddresses(instance)
+}
+
+func (cs *CSCloud) nodeAddresses(instance *cloudstack.VirtualMachine) ([]v1.NodeAddress, error) {
+	if len(instance.Nic) == 0 {
+		return nil, errors.New("instance does not have an internal IP")
+	}
+
+	addresses := []v1.NodeAddress{
+		{Type: v1.NodeInternalIP, Address: instance.Nic[0].Ipaddress},
+	}
+
+	if instance.Publicip != "" {
+		addresses = append(addresses, v1.NodeAddress{Type: v1.NodeExternalIP, Address: instance.Publicip})
+	} else {
+		// Since there is no sane way to determine the external IP if the host isn't
+		// using static NAT, we will just fire a log message and omit the external IP.
+		glog.V(4).Infof("Could not determine the public IP of host %v (%v)", instance.Name, instance.Id)
+	}
+
+	return addresses, nil
+}
+
+// ExternalID returns the cloud provider ID of the specified instance (deprecated).
+func (cs *CSCloud) ExternalID(name types.NodeName) (string, error) {
+	return cs.InstanceID(name)
+}
+
+// InstanceID returns the cloud provider ID of the specified instance.
+func (cs *CSCloud) InstanceID(name types.NodeName) (string, error) {
+	instance, count, err := cs.client.VirtualMachine.GetVirtualMachineByName(
+		string(name),
+		cloudstack.WithProject(cs.projectID),
+	)
+	if err != nil {
+		if count == 0 {
+			return "", cloudprovider.InstanceNotFound
+		}
+		return "", fmt.Errorf("error retrieving instance ID: %v", err)
+	}
+
+	return instance.Id, nil
+}
+
+// InstanceType returns the type of the specified instance.
+func (cs *CSCloud) InstanceType(name types.NodeName) (string, error) {
+	instance, count, err := cs.client.VirtualMachine.GetVirtualMachineByName(
+		string(name),
+		cloudstack.WithProject(cs.projectID),
+	)
+	if err != nil {
+		if count == 0 {
+			return "", cloudprovider.InstanceNotFound
+		}
+		return "", fmt.Errorf("error retrieving instance type: %v", err)
+	}
+
+	return instance.Serviceofferingname, nil
+}
+
+// InstanceTypeByProviderID returns the type of the specified instance.
+func (cs *CSCloud) InstanceTypeByProviderID(providerID string) (string, error) {
+	instance, count, err := cs.client.VirtualMachine.GetVirtualMachineByID(
+		providerID,
+		cloudstack.WithProject(cs.projectID),
+	)
+	if err != nil {
+		if count == 0 {
+			return "", cloudprovider.InstanceNotFound
+		}
+		return "", fmt.Errorf("error retrieving instance type: %v", err)
+	}
+
+	return instance.Serviceofferingname, nil
+}
+
+// AddSSHKeyToAllInstances is currently not implemented.
+func (cs *CSCloud) AddSSHKeyToAllInstances(user string, keyData []byte) error {
+	return errors.New("AddSSHKeyToAllInstances not implemented")
+}
+
+// CurrentNodeName returns the name of the node we are currently running on.
+func (cs *CSCloud) CurrentNodeName(hostname string) (types.NodeName, error) {
+	return types.NodeName(hostname), nil
+}
+
+// InstanceExistsByProviderID returns if the instance still exists.
+func (cs *CSCloud) InstanceExistsByProviderID(providerID string) (bool, error) {
+	_, count, err := cs.client.VirtualMachine.GetVirtualMachineByID(
+		providerID,
+		cloudstack.WithProject(cs.projectID),
+	)
+	if err != nil {
+		if count == 0 {
+			return false, nil
+		}
+		return false, fmt.Errorf("error retrieving instance: %v", err)
+	}
+
+	return true, nil
+}

pkg/cloudprovider/providers/cloudstack/cloudstack_test.go

@@ -30,8 +30,8 @@ const testClusterName = "testCluster"
 
 func TestReadConfig(t *testing.T) {
 	_, err := readConfig(nil)
-	if err == nil {
-		t.Errorf("Should fail when no config is provided: %v", err)
+	if err != nil {
+		t.Fatalf("Should not return an error when no config is provided: %v", err)
 	}
 
 	cfg, err := readConfig(strings.NewReader(`
@@ -41,7 +41,6 @@ func TestReadConfig(t *testing.T) {
  secret-key			= a-valid-secret-key
  ssl-no-verify	= true
  project-id			= a-valid-project-id
- zone						= a-valid-zone
  `))
 	if err != nil {
 		t.Fatalf("Should succeed when a valid config is provided: %v", err)
@@ -59,9 +58,6 @@ func TestReadConfig(t *testing.T) {
 	if !cfg.Global.SSLNoVerify {
 		t.Errorf("incorrect ssl-no-verify: %t", cfg.Global.SSLNoVerify)
 	}
-	if cfg.Global.Zone != "a-valid-zone" {
-		t.Errorf("incorrect zone: %s", cfg.Global.Zone)
-	}
 }
 
 // This allows acceptance testing against an existing CloudStack environment.
@@ -72,7 +68,6 @@ func configFromEnv() (*CSConfig, bool) {
 	cfg.Global.APIKey = os.Getenv("CS_API_KEY")
 	cfg.Global.SecretKey = os.Getenv("CS_SECRET_KEY")
 	cfg.Global.ProjectID = os.Getenv("CS_PROJECT_ID")
-	cfg.Global.Zone = os.Getenv("CS_ZONE")
 
 	// It is save to ignore the error here. If the input cannot be parsed SSLNoVerify
 	// will still be a bool with its zero value (false) which is the expected default.
@@ -120,23 +115,3 @@ func TestLoadBalancer(t *testing.T) {
 		t.Fatalf("GetLoadBalancer(\"noexist\") returned exists")
 	}
 }
-
-func TestZones(t *testing.T) {
-	cs := &CSCloud{
-		zone: "myRegion",
-	}
-
-	z, ok := cs.Zones()
-	if !ok {
-		t.Fatalf("Zones() returned false")
-	}
-
-	zone, err := z.GetZone()
-	if err != nil {
-		t.Fatalf("GetZone() returned error: %s", err)
-	}
-
-	if zone.Region != "myRegion" {
-		t.Fatalf("GetZone() returned wrong region (%s)", zone.Region)
-	}
-}

pkg/cloudprovider/providers/cloudstack/metadata.go

+/*
+Copyright 2016 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package cloudstack
+
+import (
+	"errors"
+	"fmt"
+	"io/ioutil"
+	"net"
+	"net/http"
+
+	"github.com/d2g/dhcp4"
+	"github.com/golang/glog"
+	"k8s.io/api/core/v1"
+	"k8s.io/apimachinery/pkg/types"
+	"k8s.io/kubernetes/pkg/cloudprovider"
+)
+
+type metadata struct {
+	dhcpServer string
+	zone       string
+}
+
+type metadataType string
+
+const (
+	metadataTypeExternalIP   metadataType = "public-ipv4"
+	metadataTypeInternalIP   metadataType = "local-ipv4"
+	metadataTypeInstanceID   metadataType = "instance-id"
+	metadataTypeInstanceType metadataType = "service-offering"
+	metadataTypeZone         metadataType = "availability-zone"
+)
+
+// NodeAddresses returns the addresses of the specified instance.
+func (m *metadata) NodeAddresses(name types.NodeName) ([]v1.NodeAddress, error) {
+	externalIP, err := m.get(metadataTypeExternalIP)
+	if err != nil {
+		return nil, fmt.Errorf("could not get external IP: %v", err)
+	}
+
+	internalIP, err := m.get(metadataTypeInternalIP)
+	if err != nil {
+		return nil, fmt.Errorf("could not get internal IP: %v", err)
+	}
+
+	return []v1.NodeAddress{
+		{Type: v1.NodeExternalIP, Address: externalIP},
+		{Type: v1.NodeInternalIP, Address: internalIP},
+	}, nil
+}
+
+// NodeAddressesByProviderID returns the addresses of the specified instance.
+func (m *metadata) NodeAddressesByProviderID(providerID string) ([]v1.NodeAddress, error) {
+	return nil, errors.New("NodeAddressesByProviderID not implemented")
+}
+
+// ExternalID returns the cloud provider ID of the specified instance (deprecated).
+func (m *metadata) ExternalID(name types.NodeName) (string, error) {
+	return m.InstanceID(name)
+}
+
+// InstanceID returns the cloud provider ID of the specified instance.
+func (m *metadata) InstanceID(name types.NodeName) (string, error) {
+	instanceID, err := m.get(metadataTypeInstanceID)
+	if err != nil {
+		return "", fmt.Errorf("could not get instance ID: %v", err)
+	}
+
+	zone, err := m.get(metadataTypeZone)
+	if err != nil {
+		return "", fmt.Errorf("could not get zone: %v", err)
+	}
+
+	return "/" + zone + "/" + instanceID, nil
+}
+
+// InstanceType returns the type of the specified instance.
+func (m *metadata) InstanceType(name types.NodeName) (string, error) {
+	instanceType, err := m.get(metadataTypeInstanceType)
+	if err == nil {
+		return "", fmt.Errorf("could not get instance type: %v", err)
+	}
+
+	return instanceType, nil
+}
+
+// InstanceTypeByProviderID returns the type of the specified instance.
+func (m *metadata) InstanceTypeByProviderID(providerID string) (string, error) {
+	return "", errors.New("InstanceTypeByProviderID not implemented")
+}
+
+// AddSSHKeyToAllInstances is currently not implemented.
+func (m *metadata) AddSSHKeyToAllInstances(user string, keyData []byte) error {
+	return errors.New("AddSSHKeyToAllInstances not implemented")
+}
+
+// CurrentNodeName returns the name of the node we are currently running on.
+func (m *metadata) CurrentNodeName(hostname string) (types.NodeName, error) {
+	return types.NodeName(hostname), nil
+}
+
+// InstanceExistsByProviderID returns if the instance still exists.
+func (m *metadata) InstanceExistsByProviderID(providerID string) (bool, error) {
+	return false, errors.New("InstanceExistsByProviderID not implemented")
+}
+
+// GetZone returns the Zone containing the region that the program is running in.
+func (m *metadata) GetZone() (cloudprovider.Zone, error) {
+	zone := cloudprovider.Zone{}
+
+	if m.zone == "" {
+		zoneName, err := m.get(metadataTypeZone)
+		if err != nil {
+			return zone, fmt.Errorf("could not get zone: %v", err)
+		}
+
+		m.zone = zoneName
+	}
+
+	glog.V(2).Infof("Current zone is %v", zone)
+	zone.FailureDomain = m.zone
+	zone.Region = m.zone
+
+	return zone, nil
+}
+
+// GetZoneByProviderID returns the Zone, found by using the provider ID.
+func (m *metadata) GetZoneByProviderID(providerID string) (cloudprovider.Zone, error) {
+	return cloudprovider.Zone{}, errors.New("GetZoneByProviderID not implemented")
+}
+
+// GetZoneByNodeName returns the Zone, found by using the node name.
+func (m *metadata) GetZoneByNodeName(nodeName types.NodeName) (cloudprovider.Zone, error) {
+	return cloudprovider.Zone{}, errors.New("GetZoneByNodeName not implemented")
+}
+
+func (m *metadata) get(mdType metadataType) (string, error) {
+	url := fmt.Sprintf("http://%s/latest/meta-data/%s", m.dhcpServer, mdType)
+
+	resp, err := http.Get(url)
+	if err != nil {
+		return "", fmt.Errorf("error reading metadata: %v", err)
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode != http.StatusOK {
+		return "", fmt.Errorf("unexpected HTTP status: %d", resp.StatusCode)
+	}
+
+	data, err := ioutil.ReadAll(resp.Body)
+	if err != nil {
+		return "", fmt.Errorf("error reading response body: %d", resp.StatusCode)
+	}
+
+	return string(data), nil
+}
+
+func findDHCPServer() (string, error) {
+	nics, err := net.Interfaces()
+	if err != nil {
+		return "", fmt.Errorf("could not get interfaces: %v", err)
+	}
+
+	for _, nic := range nics {
+		if nic.Flags&net.FlagUp == 1 && nic.Flags&net.FlagLoopback == 0 && nic.Flags&net.FlagPointToPoint == 0 {
+			addrs, err := nic.Addrs()
+			if err != nil {
+				return "", fmt.Errorf("error reading IP addresses from interface %v: %v", nic.Name, err)
+			}
+
+			if addrs != nil {
+				client, err := newDHCPClient(&nic)
+				if err != nil {
+					return "", fmt.Errorf("error creating new DHCP client: %v", err)
+				}
+
+				discoverPacket, err := client.SendDiscoverPacket()
+				if err != nil {
+					return "", fmt.Errorf("error sending DHCP discover package: %v", err)
+				}
+
+				offerPacket, err := client.GetOffer(&discoverPacket)
+				if err != nil {
+					return "", fmt.Errorf("error recieving DHCP offer package: %v", err)
+				}
+
+				offerPacketOptions := offerPacket.ParseOptions()
+
+				if ipaddr, ok := offerPacketOptions[dhcp4.OptionServerIdentifier]; ok {
+					return net.IP(ipaddr).String(), nil
+				}
+			}
+		}
+	}
+
+	return "", errors.New("no server found")
+}

pkg/cloudprovider/providers/cloudstack/metadata_linux.go

+// +build linux
+
+/*
+Copyright 2016 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package cloudstack
+
+import (
+	"net"
+	"time"
+
+	"github.com/d2g/dhcp4client"
+)
+
+func newDHCPClient(nic *net.Interface) (*dhcp4client.Client, error) {
+	pktsock, err := dhcp4client.NewPacketSock(nic.Index)
+	if err != nil {
+		return nil, err
+	}
+
+	return dhcp4client.New(
+		dhcp4client.HardwareAddr(nic.HardwareAddr),
+		dhcp4client.Timeout(2*time.Second),
+		dhcp4client.Broadcast(false),
+		dhcp4client.Connection(pktsock),
+	)
+}

pkg/cloudprovider/providers/cloudstack/metadata_other.go

+// +build !linux
+
+/*
+Copyright 2016 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package cloudstack
+
+import (
+	"net"
+	"time"
+
+	"github.com/d2g/dhcp4client"
+)
+
+func newDHCPClient(nic *net.Interface) (*dhcp4client.Client, error) {
+	inetsock, err := dhcp4client.NewInetSock()
+	if err != nil {
+		return nil, err
+	}
+
+	return dhcp4client.New(
+		dhcp4client.HardwareAddr(nic.HardwareAddr),
+		dhcp4client.Timeout(2*time.Second),
+		dhcp4client.Broadcast(false),
+		dhcp4client.Connection(inetsock),
+	)
+}