providers/aws: add source_security_group to elb

builtin/providers/aws/resource_aws_elb.go

@@ -70,6 +70,12 @@ func resourceAwsElb() *schema.Resource {
 				},
 			},
 
+			"source_security_group": &schema.Schema{
+				Type:     schema.TypeString,
+				Optional: true,
+				Computed: true,
+			},
+
 			"subnets": &schema.Schema{
 				Type:     schema.TypeSet,
 				Elem:     &schema.Schema{Type: schema.TypeString},
@@ -282,6 +288,9 @@ func resourceAwsElbRead(d *schema.ResourceData, meta interface{}) error {
 	d.Set("instances", flattenInstances(lb.Instances))
 	d.Set("listener", flattenListeners(lb.ListenerDescriptions))
 	d.Set("security_groups", lb.SecurityGroups)
+	if lb.SourceSecurityGroup != nil {
+		d.Set("source_security_group", lb.SourceSecurityGroup.GroupName)
+	}
 	d.Set("subnets", lb.Subnets)
 	d.Set("idle_timeout", lbAttrs.ConnectionSettings.IdleTimeout)
 	d.Set("connection_draining", lbAttrs.ConnectionDraining.Enabled)

website/source/docs/providers/aws/r/elb.html.markdown

@@ -93,3 +93,6 @@ The following attributes are exported:
 * `name` - The name of the ELB
 * `dns_name` - The DNS name of the ELB
 * `instances` - The list of instances in the ELB
+* `source_security_group` - The name of the security group that you can use as
+  part of your inbound rules for your load balancer's back-end application
+  instances.