Merge pull request #2038 from dgageot/brownoxford-validate-cidr

Additional validation on virtualbox-hostonly-cidr

drivers/virtualbox/virtualbox.go

@@ -45,6 +45,7 @@ const (
 var (
 	ErrUnableToGenerateRandomIP = errors.New("unable to generate random IP")
 	ErrMustEnableVTX            = errors.New("This computer doesn't have VT-X/AMD-v enabled. Enabling it in the BIOS is mandatory.")
+	ErrNetworkAddrCidr          = errors.New("host-only cidr must be specified with a host address, not a network address")
 )
 
 type Driver struct {
@@ -658,19 +659,17 @@ func (d *Driver) setupHostOnlyNetwork(machineName string) error {
 		hostOnlyCIDR = defaultHostOnlyCIDR
 	}
 
-	ip, network, err := net.ParseCIDR(hostOnlyCIDR)
-
+	ip, network, err := parseAndValidateCIDR(hostOnlyCIDR)
 	if err != nil {
 		return err
 	}
 
-	nAddr := network.IP.To4()
-
 	dhcpAddr, err := getRandomIPinSubnet(network.IP)
 	if err != nil {
 		return err
 	}
 
+	nAddr := network.IP.To4()
 	lowerDHCPIP := net.IPv4(nAddr[0], nAddr[1], nAddr[2], byte(100))
 	upperDHCPIP := net.IPv4(nAddr[0], nAddr[1], nAddr[2], byte(254))
 
@@ -695,6 +694,20 @@ func (d *Driver) setupHostOnlyNetwork(machineName string) error {
 		"--cableconnected2", "on")
 }
 
+func parseAndValidateCIDR(hostOnlyCIDR string) (net.IP, *net.IPNet, error) {
+	ip, network, err := net.ParseCIDR(hostOnlyCIDR)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	networkAddress := network.IP.To4()
+	if ip.Equal(networkAddress) {
+		return nil, nil, ErrNetworkAddrCidr
+	}
+
+	return ip, network, nil
+}
+
 // createDiskImage makes a disk image at dest with the given size in MB. If r is
 // not nil, it will be read as a raw disk image to convert from.
 func createDiskImage(dest string, size int, r io.Reader) error {

drivers/virtualbox/virtualbox_test.go

@@ -152,6 +152,31 @@ func TestGetIPErrors(t *testing.T) {
 	}
 }
 
+func TestParseValidCIDR(t *testing.T) {
+	ip, network, err := parseAndValidateCIDR("192.168.100.1/24")
+
+	assert.Equal(t, "192.168.100.1", ip.String())
+	assert.Equal(t, "192.168.100.0", network.IP.String())
+	assert.Equal(t, "ffffff00", network.Mask.String())
+	assert.NoError(t, err)
+}
+
+func TestInvalidCIDR(t *testing.T) {
+	ip, network, err := parseAndValidateCIDR("192.168.100.1")
+
+	assert.EqualError(t, err, "invalid CIDR address: 192.168.100.1")
+	assert.Nil(t, ip)
+	assert.Nil(t, network)
+}
+
+func TestInvalidNetworkIpCIDR(t *testing.T) {
+	ip, network, err := parseAndValidateCIDR("192.168.100.0/24")
+
+	assert.Equal(t, ErrNetworkAddrCidr, err)
+	assert.Nil(t, ip)
+	assert.Nil(t, network)
+}
+
 func newTestDriver(name string) *Driver {
 	return NewDriver(name, "")
 }