Support IP forwarding on GCE instances

This change exposes the CanIpForward property of the Instance, allowing
users to create instances that are allowed to function as NAT or VPN
gateways.

resource_compute_instance.go

@@ -97,6 +97,13 @@ func resourceComputeInstance() *schema.Resource {
 				},
 			},
 
+			"can_ip_forward": &schema.Schema{
+				Type:     schema.TypeBool,
+				Optional: true,
+				Default:  false,
+				ForceNew: true,
+			},
+
 			"metadata": &schema.Schema{
 				Type:     schema.TypeList,
 				Optional: true,
@@ -230,6 +237,7 @@ func resourceComputeInstanceCreate(d *schema.ResourceData, meta interface{}) err
 
 	// Create the instance information
 	instance := compute.Instance{
+		CanIpForward:      d.Get("can_ip_forward").(bool),
 		Description:       d.Get("description").(string),
 		Disks:             disks,
 		MachineType:       machineType.SelfLink,
@@ -305,6 +313,8 @@ func resourceComputeInstanceRead(d *schema.ResourceData, meta interface{}) error
 		return fmt.Errorf("Error reading instance: %s", err)
 	}
 
+	d.Set("can_ip_forward", instance.CanIpForward)
+
 	// Set the networks
 	for i, iface := range instance.NetworkInterfaces {
 		prefix := fmt.Sprintf("network.%d", i)

resource_compute_instance_test.go

@@ -225,6 +225,7 @@ resource "google_compute_instance" "foobar" {
 	name = "terraform-test"
 	machine_type = "n1-standard-1"
 	zone = "us-central1-a"
+	can_ip_forward = false
 	tags = ["foo", "bar"]
 
 	disk {