Merge pull request #325 from vrindle/generate_random_mac_address_for_vfs

Generate random mac address when virtual mac address is zero.

pkg/utils/utils.go

@@ -330,6 +330,7 @@ func configSriovDevice(iface *sriovnetworkv1.Interface, ifaceStatus *sriovnetwor
 							return err
 						}
 					}
+
 					if err = setVfAdminMac(addr, pfLink, vfLink); err != nil {
 						glog.Errorf("configSriovDevice(): fail to configure VF admin mac address for device %s %q", addr, err)
 						return err
@@ -375,6 +376,17 @@ func configSriovDevice(iface *sriovnetworkv1.Interface, ifaceStatus *sriovnetwor
 	return nil
 }
 
+func generateRandomMacAddressVfs() ([]byte, error) {
+	buf := make([]byte, 6)
+	_, err := rand.Read(buf)
+	if err != nil {
+		return buf, err
+	}
+	// Set the local bit
+	buf[0] = (buf[0] & 0xfe) | 2
+	return buf, nil
+}
+
 func setSriovNumVfs(pciAddr string, numVfs int) error {
 	glog.V(2).Infof("setSriovNumVfs(): set NumVfs for device %s", pciAddr)
 	numVfsFilePath := filepath.Join(sysBusPciDevices, pciAddr, numVfsFile)
@@ -600,6 +612,35 @@ func vfIsReady(pciAddr string) (netlink.Link, error) {
 	return vfLink, nil
 }
 
+func isValidAddress(address []byte) bool {
+	invalidAddresses := [][]byte{
+		{0x00, 0x00, 0x00, 0x00, 0x00, 0x00},
+		{0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF},
+	}
+	for _, invalidAddress := range invalidAddresses {
+		if bytes.Equal(address, invalidAddress) {
+			return false
+		}
+	}
+	return true
+}
+
+func getEffectiveMacAddress(hwAddr net.HardwareAddr) (net.HardwareAddr, error) {
+	newAddr := []byte{0x00, 0x00, 0x00, 0x00, 0x00, 0x00}
+	zeroAddr := net.HardwareAddr(newAddr[:])
+	if bytes.Equal(hwAddr, zeroAddr) {
+		for !isValidAddress(newAddr) {
+			newAddr2, err := generateRandomMacAddressVfs()
+			newAddr = newAddr2
+			if err != nil {
+				return nil, err
+			}
+		}
+		return net.HardwareAddr(newAddr[:]), nil
+	}
+	return hwAddr, nil
+}
+
 func setVfAdminMac(vfAddr string, pfLink, vfLink netlink.Link) error {
 	glog.Infof("setVfAdminMac(): VF %s", vfAddr)
 
@@ -608,8 +649,12 @@ func setVfAdminMac(vfAddr string, pfLink, vfLink netlink.Link) error {
 		glog.Errorf("setVfAdminMac(): unable to get VF id %+v %q", vfAddr, err)
 		return err
 	}
+	hwAddr, err := getEffectiveMacAddress(vfLink.Attrs().HardwareAddr)
+	if err != nil {
+		return err
+	}
 
-	if err := netlink.LinkSetVfHardwareAddr(pfLink, vfID, vfLink.Attrs().HardwareAddr); err != nil {
+	if err := netlink.LinkSetVfHardwareAddr(pfLink, vfID, hwAddr); err != nil {
 		return err
 	}