func TestGenerateRandomMAC(t *testing.T) {
	defer osl.SetupTestOSContext(t)()

	mac1 := netutils.GenerateRandomMAC()
	mac2 := netutils.GenerateRandomMAC()
	if bytes.Compare(mac1, mac2) == 0 {
		t.Fatalf("Generated twice the same MAC address %v", mac1)
	}
}

// SetupDevice create a new bridge interface/
func setupDevice(config *networkConfiguration, i *bridgeInterface) error {
	// We only attempt to create the bridge when the requested device name is
	// the default one.
	if config.BridgeName != DefaultBridgeName && !config.AllowNonDefaultBridge {
		return NonDefaultBridgeExistError(config.BridgeName)
	}

	// Set the bridgeInterface netlink.Bridge.
	i.Link = &netlink.Bridge{
		LinkAttrs: netlink.LinkAttrs{
			Name: config.BridgeName,
		},
	}

	// Only set the bridge's MAC address if the kernel version is > 3.3, as it
	// was not supported before that.
	kv, err := kernel.GetKernelVersion()
	if err == nil && (kv.Kernel >= 3 && kv.Major >= 3) {
		i.Link.Attrs().HardwareAddr = netutils.GenerateRandomMAC()
		log.Debugf("Setting bridge mac address to %s", i.Link.Attrs().HardwareAddr)
	}

	// Call out to netlink to create the device.
	if err = netlink.LinkAdd(i.Link); err != nil {
		return types.InternalErrorf("Failed to program bridge link: %s", err.Error())
	}
	return nil
}

func (d *driver) CreateEndpoint(nid, eid types.UUID, epInfo driverapi.EndpointInfo,
	epOptions map[string]interface{}) error {
	if err := validateID(nid, eid); err != nil {
		return err
	}

	n := d.network(nid)
	if n == nil {
		return fmt.Errorf("network id %q not found", nid)
	}

	ep := &endpoint{
		id: eid,
	}

	if epInfo != nil && (len(epInfo.Interfaces()) > 0) {
		addr := epInfo.Interfaces()[0].Address()
		ep.addr = &addr
		ep.mac = epInfo.Interfaces()[0].MacAddress()
		n.addEndpoint(ep)
		return nil
	}

	ipID, err := d.ipAllocator.GetID()
	if err != nil {
		return fmt.Errorf("could not allocate ip from subnet %s: %v",
			bridgeSubnet.String(), err)
	}

	ep.addr = &net.IPNet{
		Mask: bridgeSubnet.Mask,
	}
	ep.addr.IP = make([]byte, 4)

	binary.BigEndian.PutUint32(ep.addr.IP, bridgeSubnetInt+ipID)

	ep.mac = netutils.GenerateRandomMAC()

	err = epInfo.AddInterface(1, ep.mac, *ep.addr, net.IPNet{})
	if err != nil {
		return fmt.Errorf("could not add interface to endpoint info: %v", err)
	}

	n.addEndpoint(ep)

	return nil
}

// SetupDevice create a new bridge interface/
func setupDevice(config *networkConfiguration, i *bridgeInterface) error {
	var setMac bool

	// We only attempt to create the bridge when the requested device name is
	// the default one.
	if config.BridgeName != DefaultBridgeName && !config.AllowNonDefaultBridge {
		return NonDefaultBridgeExistError(config.BridgeName)
	}

	// Set the bridgeInterface netlink.Bridge.
	i.Link = &netlink.Bridge{
		LinkAttrs: netlink.LinkAttrs{
			Name: config.BridgeName,
		},
	}

	// Only set the bridge's MAC address if the kernel version is > 3.3, as it
	// was not supported before that.
	kv, err := kernel.GetKernelVersion()
	if err != nil {
		logrus.Errorf("Failed to check kernel versions: %v. Will not assign a MAC address to the bridge interface", err)
	} else {
		setMac = kv.Kernel > 3 || (kv.Kernel == 3 && kv.Major >= 3)
	}

	if err = netlink.LinkAdd(i.Link); err != nil {
		logrus.Debugf("Failed to create bridge %s via netlink. Trying ioctl", config.BridgeName)
		return ioctlCreateBridge(config.BridgeName, setMac)
	}

	if setMac {
		hwAddr := netutils.GenerateRandomMAC()
		if err = netlink.LinkSetHardwareAddr(i.Link, hwAddr); err != nil {
			return fmt.Errorf("failed to set bridge mac-address %s : %s", hwAddr, err.Error())
		}
		logrus.Debugf("Setting bridge mac address to %s", hwAddr)
		logrus.Debugf("call recieved to bridge driver, PLUMgrid")
	}
	return err
}

func ioctlCreateBridge(name string, setMacAddr bool) error {
	if len(name) >= ifNameSize {
		return fmt.Errorf("Interface name %s too long", name)
	}

	s, err := getIfSocket()
	if err != nil {
		return err
	}
	defer syscall.Close(s)

	nameBytePtr, err := syscall.BytePtrFromString(name)
	if err != nil {
		return err
	}
	if _, _, err := syscall.Syscall(syscall.SYS_IOCTL, uintptr(s), ioctlBrAdd, uintptr(unsafe.Pointer(nameBytePtr))); err != 0 {
		return err
	}
	if setMacAddr {
		return ioctlSetMacAddress(name, netutils.GenerateRandomMAC().String())
	}
	return nil
}

func (n *network) CreateEndpoint(name string, options ...EndpointOption) (Endpoint, error) {
	var err error
	if !config.IsValidName(name) {
		return nil, ErrInvalidName(name)
	}

	if _, err = n.EndpointByName(name); err == nil {
		return nil, types.ForbiddenErrorf("service endpoint with name %s already exists", name)
	}

	ep := &endpoint{name: name, generic: make(map[string]interface{}), iface: &endpointInterface{}}
	ep.id = stringid.GenerateRandomID()

	// Initialize ep.network with a possibly stale copy of n. We need this to get network from
	// store. But once we get it from store we will have the most uptodate copy possibly.
	ep.network = n
	ep.locator = n.getController().clusterHostID()
	ep.network, err = ep.getNetworkFromStore()
	if err != nil {
		return nil, fmt.Errorf("failed to get network during CreateEndpoint: %v", err)
	}
	n = ep.network

	ep.processOptions(options...)

	for _, llIPNet := range ep.Iface().LinkLocalAddresses() {
		if !llIPNet.IP.IsLinkLocalUnicast() {
			return nil, types.BadRequestErrorf("invalid link local IP address: %v", llIPNet.IP)
		}
	}

	if opt, ok := ep.generic[netlabel.MacAddress]; ok {
		if mac, ok := opt.(net.HardwareAddr); ok {
			ep.iface.mac = mac
		}
	}

	ipam, cap, err := n.getController().getIPAMDriver(n.ipamType)
	if err != nil {
		return nil, err
	}

	if cap.RequiresMACAddress {
		if ep.iface.mac == nil {
			ep.iface.mac = netutils.GenerateRandomMAC()
		}
		if ep.ipamOptions == nil {
			ep.ipamOptions = make(map[string]string)
		}
		ep.ipamOptions[netlabel.MacAddress] = ep.iface.mac.String()
	}

	if err = ep.assignAddress(ipam, true, n.enableIPv6 && !n.postIPv6); err != nil {
		return nil, err
	}
	defer func() {
		if err != nil {
			ep.releaseAddress()
		}
	}()

	if err = n.addEndpoint(ep); err != nil {
		return nil, err
	}
	defer func() {
		if err != nil {
			if e := ep.deleteEndpoint(false); e != nil {
				log.Warnf("cleaning up endpoint failed %s : %v", name, e)
			}
		}
	}()

	if err = ep.assignAddress(ipam, false, n.enableIPv6 && n.postIPv6); err != nil {
		return nil, err
	}

	if err = n.getController().updateToStore(ep); err != nil {
		return nil, err
	}
	defer func() {
		if err != nil {
			if e := n.getController().deleteFromStore(ep); e != nil {
				log.Warnf("error rolling back endpoint %s from store: %v", name, e)
			}
		}
	}()

	// Watch for service records
	n.getController().watchSvcRecord(ep)
	defer func() {
		if err != nil {
			n.getController().unWatchSvcRecord(ep)
		}
	}()

	// Increment endpoint count to indicate completion of endpoint addition
	if err = n.getEpCnt().IncEndpointCnt(); err != nil {
		return nil, err
	}

//.........这里部分代码省略.........

func (d *driver) CreateEndpoint(nid, eid string, ifInfo driverapi.InterfaceInfo, epOptions map[string]interface{}) error {
	if ifInfo == nil {
		return errors.New("invalid interface passed")
	}

	// Get the network handler and make sure it exists
	d.Lock()
	n, ok := d.networks[nid]
	d.Unlock()

	if !ok {
		return types.NotFoundErrorf("network %s does not exist", nid)
	}
	if n == nil {
		return driverapi.ErrNoNetwork(nid)
	}

	// Sanity check
	n.Lock()
	if n.id != nid {
		n.Unlock()
		return InvalidNetworkIDError(nid)
	}
	n.Unlock()

	// Check if endpoint id is good and retrieve correspondent endpoint
	ep, err := n.getEndpoint(eid)
	if err != nil {
		return err
	}

	// Endpoint with that id exists either on desired or other sandbox
	if ep != nil {
		return driverapi.ErrEndpointExists(eid)
	}

	// Try to convert the options to endpoint configuration
	epConfig, err := parseEndpointOptions(epOptions)
	if err != nil {
		return err
	}

	// Create and add the endpoint
	n.Lock()
	endpoint := &bridgeEndpoint{id: eid, config: epConfig}
	n.endpoints[eid] = endpoint
	n.Unlock()

	// On failure make sure to remove the endpoint
	defer func() {
		if err != nil {
			n.Lock()
			delete(n.endpoints, eid)
			n.Unlock()
		}
	}()

	// Create the sandbox side pipe interface
	if ifInfo.MacAddress() == nil {
		// No MAC address assigned to interface. Generate a random MAC to assign
		endpoint.macAddress = netutils.GenerateRandomMAC()
		if err := ifInfo.SetMacAddress(endpoint.macAddress); err != nil {
			logrus.Warnf("Unable to set mac address: %s to endpoint: %s",
				endpoint.macAddress.String(), endpoint.id)
			return err
		}
	} else {
		endpoint.macAddress = ifInfo.MacAddress()
	}
	endpoint.addr = ifInfo.Address()
	endpoint.addrv6 = ifInfo.AddressIPv6()
	c := n.config

	// Program any required port mapping and store them in the endpoint
	endpoint.portMapping, err = n.allocatePorts(endpoint, c.DefaultBindingIntf, c.DefaultBindingIP, true)
	if err != nil {
		return err
	}

	return nil
}

func electMacAddress(epConfig *EndpointConfiguration) net.HardwareAddr {
	if epConfig != nil && epConfig.MacAddress != nil {
		return epConfig.MacAddress
	}
	return netutils.GenerateRandomMAC()
}