FIX docker#2624 reject duplicate hostonlyifs name/IP

Signed-off-by: David Gageot <david@gageot.net>

drivers/virtualbox/network.go

@@ -13,9 +13,8 @@ const (
 )
 
 var (
-	reHostonlyInterfaceCreated            = regexp.MustCompile(`Interface '(.+)' was successfully created`)
-	errDuplicateHostOnlyInterfaceNetworks = errors.New("VirtualBox is configured with multiple host-only interfaces with the same IP. Please remove all of them but one.")
-	errNewHostOnlyInterfaceNotVisible     = errors.New("The host-only interface we just created is not visible. This is a well known bug of VirtualBox. You might want to uninstall it and reinstall the version listed here: https://www.virtualbox.org/ticket/14437?cversion=0&cnum_hist=42")
+	reHostonlyInterfaceCreated        = regexp.MustCompile(`Interface '(.+)' was successfully created`)
+	errNewHostOnlyInterfaceNotVisible = errors.New("The host-only interface we just created is not visible. This is a well known bug of VirtualBox. You might want to uninstall it and reinstall the version listed here: https://www.virtualbox.org/ticket/14437?cversion=0&cnum_hist=42")
 )
 
 // Host-only network.
@@ -75,7 +74,8 @@ func listHostOnlyNetworks(vbox VBoxManager) (map[string]*hostOnlyNetwork, error)
 		return nil, err
 	}
 
-	m := map[string]*hostOnlyNetwork{}
+	byName := map[string]*hostOnlyNetwork{}
+	byIP := map[string]*hostOnlyNetwork{}
 	n := &hostOnlyNetwork{}
 
 	err = parseKeyValues(out, reColonLine, func(key, val string) error {
@@ -110,7 +110,19 @@ func listHostOnlyNetworks(vbox VBoxManager) (map[string]*hostOnlyNetwork, error)
 			n.Status = val
 		case "VBoxNetworkName":
 			n.NetworkName = val
-			m[val] = n
+
+			if _, present := byName[n.NetworkName]; present {
+				return fmt.Errorf("VirtualBox is configured with multiple host-only interfaces with the same name %q. Please remove one.", n.NetworkName)
+			}
+			byName[n.NetworkName] = n
+
+			if len(n.IPv4.IP) != 0 {
+				if _, present := byIP[n.IPv4.IP.String()]; present {
+					return fmt.Errorf("VirtualBox is configured with multiple host-only interfaces with the same IP %q. Please remove one.", n.IPv4.IP)
+				}
+				byIP[n.IPv4.IP.String()] = n
+			}
+
 			n = &hostOnlyNetwork{}
 		}
 
@@ -120,7 +132,7 @@ func listHostOnlyNetworks(vbox VBoxManager) (map[string]*hostOnlyNetwork, error)
 		return nil, err
 	}
 
-	return m, nil
+	return byName, nil
 }
 
 func getHostOnlyNetwork(nets map[string]*hostOnlyNetwork, hostIP net.IP, netmask net.IPMask) *hostOnlyNetwork {
@@ -143,10 +155,6 @@ func getOrCreateHostOnlyNetwork(hostIP net.IP, netmask net.IPMask, dhcpIP net.IP
 		return nil, err
 	}
 
-	if len(nets) != countUniqueIps(nets) {
-		return nil, errDuplicateHostOnlyInterfaceNetworks
-	}
-
 	hostOnlyNet := getHostOnlyNetwork(nets, hostIP, netmask)
 	if hostOnlyNet != nil {
 		return hostOnlyNet, nil
@@ -188,16 +196,6 @@ func getOrCreateHostOnlyNetwork(hostIP net.IP, netmask net.IPMask, dhcpIP net.IP
 	return hostOnlyNet, nil
 }
 
-func countUniqueIps(nets map[string]*hostOnlyNetwork) int {
-	ips := map[string]bool{}
-
-	for _, n := range nets {
-		ips[n.IPv4.IP.String()] = true
-	}
-
-	return len(ips)
-}
-
 // DHCP server info.
 type dhcpServer struct {
 	NetworkName string

drivers/virtualbox/network_test.go

@@ -39,7 +39,7 @@ VBoxNetworkName: HostInterfaceNetworking-vboxnet0
 Name:            vboxnet1
 GUID:            786f6276-656e-4174-8000-0a0027000001
 DHCP:            Disabled
-IPAddress:       192.168.99.1
+IPAddress:       169.254.37.187
 NetworkMask:     255.255.255.0
 IPV6Address:
 IPV6NetworkMaskPrefixLength: 0
@@ -185,7 +185,7 @@ func TestListTwoHostOnlyNetworks(t *testing.T) {
 	assert.Equal(t, "vboxnet1", net.Name)
 	assert.Equal(t, "786f6276-656e-4174-8000-0a0027000001", net.GUID)
 	assert.False(t, net.DHCP)
-	assert.Equal(t, "192.168.99.1", net.IPv4.IP.String())
+	assert.Equal(t, "169.254.37.187", net.IPv4.IP.String())
 	assert.Equal(t, "ffffff00", net.IPv4.Mask.String())
 	assert.Empty(t, net.IPv6.IP)
 	assert.Equal(t, "0a:00:27:00:00:01", net.HwAddr.String())
@@ -230,16 +230,38 @@ func TestGetHostOnlyNetwork(t *testing.T) {
 	assert.NoError(t, err)
 }
 
-func TestFailWithDuplicateHostOnlyNetworks(t *testing.T) {
+func TestFailIfTwoNetworksHaveSameIP(t *testing.T) {
 	vbox := &VBoxManagerMock{
-		args:   "list hostonlyifs",
-		stdOut: stdOutTwoHostOnlyNetwork,
+		args: "list hostonlyifs",
+		stdOut: `Name:            vboxnet0
+IPAddress:       192.168.99.1
+NetworkMask:     255.255.255.0
+VBoxNetworkName: HostInterfaceNetworking-vboxnet0
+Name:            vboxnet1
+IPAddress:       192.168.99.1
+NetworkMask:     255.255.255.0
+VBoxNetworkName: HostInterfaceNetworking-vboxnet1`,
+	}
+
+	net, err := getOrCreateHostOnlyNetwork(net.ParseIP("192.168.99.1"), parseIPv4Mask("255.255.255.0"), nil, nil, nil, vbox)
+
+	assert.Nil(t, net)
+	assert.EqualError(t, err, `VirtualBox is configured with multiple host-only interfaces with the same IP "192.168.99.1". Please remove one.`)
+}
+
+func TestFailIfTwoNetworksHaveSameName(t *testing.T) {
+	vbox := &VBoxManagerMock{
+		args: "list hostonlyifs",
+		stdOut: `Name:            vboxnet0
+VBoxNetworkName: HostInterfaceNetworking-vboxnet0
+Name:            vboxnet0
+VBoxNetworkName: HostInterfaceNetworking-vboxnet0`,
 	}
 
 	net, err := getOrCreateHostOnlyNetwork(net.ParseIP("192.168.99.1"), parseIPv4Mask("255.255.255.0"), nil, nil, nil, vbox)
 
 	assert.Nil(t, net)
-	assert.Equal(t, errDuplicateHostOnlyInterfaceNetworks, err)
+	assert.EqualError(t, err, `VirtualBox is configured with multiple host-only interfaces with the same name "HostInterfaceNetworking-vboxnet0". Please remove one.`)
 }
 
 func TestGetDHCPServers(t *testing.T) {

drivers/virtualbox/virtualbox.go

@@ -223,6 +223,11 @@ func (d *Driver) PreCreateCheck() error {
 		return err
 	}
 
+	// Check that Host-only interfaces are ok
+	if _, err = listHostOnlyNetworks(d.VBoxManager); err != nil {
+		return err
+	}
+
 	return nil
 }