Merge pull request #424 from mavenugo/nlioctl

Prefer Netlink over ioctl

libnetwork/drivers/bridge/bridge.go

@@ -763,17 +763,26 @@ func (d *driver) DeleteNetwork(nid types.UUID) error {
 }
 
 func addToBridge(ifaceName, bridgeName string) error {
-	iface, err := net.InterfaceByName(ifaceName)
+	link, err := netlink.LinkByName(ifaceName)
 	if err != nil {
 		return fmt.Errorf("could not find interface %s: %v", ifaceName, err)
 	}
+	if err = netlink.LinkSetMaster(link,
+		&netlink.Bridge{LinkAttrs: netlink.LinkAttrs{Name: bridgeName}}); err != nil {
+		logrus.Debugf("Failed to add %s to bridge via netlink.Trying ioctl: %v", ifaceName, err)
+		iface, err := net.InterfaceByName(ifaceName)
+		if err != nil {
+			return fmt.Errorf("could not find network interface %s: %v", ifaceName, err)
+		}
 
-	master, err := net.InterfaceByName(bridgeName)
-	if err != nil {
-		return fmt.Errorf("could not find bridge %s: %v", bridgeName, err)
-	}
+		master, err := net.InterfaceByName(bridgeName)
+		if err != nil {
+			return fmt.Errorf("could not find bridge %s: %v", bridgeName, err)
+		}
 
-	return ioctlAddToBridge(iface, master)
+		return ioctlAddToBridge(iface, master)
+	}
+	return nil
 }
 
 func setHairpinMode(link netlink.Link, enable bool) error {

libnetwork/drivers/bridge/setup_device.go

@@ -1,8 +1,11 @@
 package bridge
 
 import (
+	"fmt"
+
 	"github.com/Sirupsen/logrus"
 	"github.com/docker/docker/pkg/parsers/kernel"
+	"github.com/docker/libnetwork/netutils"
 	"github.com/vishvananda/netlink"
 )
 
@@ -32,7 +35,19 @@ func setupDevice(config *networkConfiguration, i *bridgeInterface) error {
 		setMac = kv.Kernel > 3 || (kv.Kernel == 3 && kv.Major >= 3)
 	}
 
-	return ioctlCreateBridge(config.BridgeName, setMac)
+	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)
+	}
+	return err
 }
 
 // SetupDeviceUp ups the given bridge interface.