metadata: implement GetLoadBalancerEndpoint for AWS

go.mod

@@ -137,10 +137,12 @@ require (
 	github.com/aws/aws-sdk-go-v2/internal/endpoints/v2 v2.4.19 // indirect
 	github.com/aws/aws-sdk-go-v2/internal/ini v1.3.24 // indirect
 	github.com/aws/aws-sdk-go-v2/internal/v4a v1.0.14 // indirect
+	github.com/aws/aws-sdk-go-v2/service/elasticloadbalancingv2 v1.18.21
 	github.com/aws/aws-sdk-go-v2/service/internal/accept-encoding v1.9.9 // indirect
 	github.com/aws/aws-sdk-go-v2/service/internal/checksum v1.1.18 // indirect
 	github.com/aws/aws-sdk-go-v2/service/internal/presigned-url v1.9.19 // indirect
 	github.com/aws/aws-sdk-go-v2/service/internal/s3shared v1.13.17 // indirect
+	github.com/aws/aws-sdk-go-v2/service/resourcegroupstaggingapi v1.13.20
 	github.com/aws/aws-sdk-go-v2/service/sso v1.11.23 // indirect
 	github.com/aws/aws-sdk-go-v2/service/ssooidc v1.13.6 // indirect
 	github.com/aws/aws-sdk-go-v2/service/sts v1.16.19 // indirect

go.sum

@@ -215,6 +215,7 @@ github.com/aws/aws-sdk-go v1.27.0/go.mod h1:KmX6BPdI08NWTb3/sm4ZGu5ShLoqVDhKgpiN
 github.com/aws/aws-sdk-go v1.37.0/go.mod h1:hcU610XS61/+aQV88ixoOzUoG7v3b31pl2zKMmprdro=
 github.com/aws/aws-sdk-go-v2 v0.18.0/go.mod h1:JWVYvqSMppoMJC0x5wdwiImzgXTI9FuZwxzkQq9wy+g=
 github.com/aws/aws-sdk-go-v2 v1.16.16/go.mod h1:SwiyXi/1zTUZ6KIAmLK5V5ll8SiURNUYOqTerZPaF9k=
+github.com/aws/aws-sdk-go-v2 v1.17.0/go.mod h1:SwiyXi/1zTUZ6KIAmLK5V5ll8SiURNUYOqTerZPaF9k=
 github.com/aws/aws-sdk-go-v2 v1.17.1 h1:02c72fDJr87N8RAC2s3Qu0YuvMRZKNZJ9F+lAehCazk=
 github.com/aws/aws-sdk-go-v2 v1.17.1/go.mod h1:JLnGeGONAyi2lWXI1p0PCIOIy333JMVK1U7Hf0aRFLw=
 github.com/aws/aws-sdk-go-v2/aws/protocol/eventstream v1.4.8 h1:tcFliCWne+zOuUfKNRn8JdFBuWPDuISDH08wD2ULkhk=
@@ -226,9 +227,11 @@ github.com/aws/aws-sdk-go-v2/credentials v1.12.21/go.mod h1:O+4XyAt4e+oBAoIwNUYk
 github.com/aws/aws-sdk-go-v2/feature/ec2/imds v1.12.17 h1:r08j4sbZu/RVi+BNxkBJwPMUYY3P8mgSDuKkZ/ZN1lE=
 github.com/aws/aws-sdk-go-v2/feature/ec2/imds v1.12.17/go.mod h1:yIkQcCDYNsZfXpd5UX2Cy+sWA1jPgIhGTw9cOBzfVnQ=
 github.com/aws/aws-sdk-go-v2/internal/configsources v1.1.23/go.mod h1:2DFxAQ9pfIRy0imBCJv+vZ2X6RKxves6fbnEuSry6b4=
+github.com/aws/aws-sdk-go-v2/internal/configsources v1.1.24/go.mod h1:ghMzB/j2wRbPx5/4jPYxJdOtCG2ggrtY01j8K7FMBDA=
 github.com/aws/aws-sdk-go-v2/internal/configsources v1.1.25 h1:nBO/RFxeq/IS5G9Of+ZrgucRciie2qpLy++3UGZ+q2E=
 github.com/aws/aws-sdk-go-v2/internal/configsources v1.1.25/go.mod h1:Zb29PYkf42vVYQY6pvSyJCJcFHlPIiY+YKdPtwnvMkY=
 github.com/aws/aws-sdk-go-v2/internal/endpoints/v2 v2.4.17/go.mod h1:pRwaTYCJemADaqCbUAxltMoHKata7hmB5PjEXeu0kfg=
+github.com/aws/aws-sdk-go-v2/internal/endpoints/v2 v2.4.18/go.mod h1:fkQKYK/jUhCL/wNS1tOPrlYhr9vqutjCz4zZC1wBE1s=
 github.com/aws/aws-sdk-go-v2/internal/endpoints/v2 v2.4.19 h1:oRHDrwCTVT8ZXi4sr9Ld+EXk7N/KGssOr2ygNeojEhw=
 github.com/aws/aws-sdk-go-v2/internal/endpoints/v2 v2.4.19/go.mod h1:6Q0546uHDp421okhmmGfbxzq2hBqbXFNpi4k+Q1JnQA=
 github.com/aws/aws-sdk-go-v2/internal/ini v1.3.24 h1:wj5Rwc05hvUSvKuOF29IYb9QrCLjU+rHAy/x/o0DK2c=
@@ -239,6 +242,8 @@ github.com/aws/aws-sdk-go-v2/service/cloudwatchlogs v1.15.20 h1:yPyXdrZaB4SW+pn2
 github.com/aws/aws-sdk-go-v2/service/cloudwatchlogs v1.15.20/go.mod h1:p2i2jyYZzFBJeOOQ5ji2k/Yc6IvlQsG/CuHRwEi8whs=
 github.com/aws/aws-sdk-go-v2/service/ec2 v1.63.3 h1:+UHyeFhdPddRB+EkgeaKMutWiqwWrj3FIQUif3VnalM=
 github.com/aws/aws-sdk-go-v2/service/ec2 v1.63.3/go.mod h1:zul71QqzR4D1a90/5FloZiAnZ1CtuIjVH7R9MP997+A=
+github.com/aws/aws-sdk-go-v2/service/elasticloadbalancingv2 v1.18.21 h1:bKnKpB8pRBGczC8GqKdZuXK1+fa+Cz3jZOWfp/R4bGc=
+github.com/aws/aws-sdk-go-v2/service/elasticloadbalancingv2 v1.18.21/go.mod h1:HU+wcatcklGhNeBDAYmBI3IujHu1d7A9fWX+juhdxxg=
 github.com/aws/aws-sdk-go-v2/service/internal/accept-encoding v1.9.9 h1:Lh1AShsuIJTwMkoxVCAYPJgNG5H+eN6SmoUn8nOZ5wE=
 github.com/aws/aws-sdk-go-v2/service/internal/accept-encoding v1.9.9/go.mod h1:a9j48l6yL5XINLHLcOKInjdvknN+vWqPBxqeIDw7ktw=
 github.com/aws/aws-sdk-go-v2/service/internal/checksum v1.1.18 h1:BBYoNQt2kUZUUK4bIPsKrCcjVPUMNsgQpNAwhznK/zo=
@@ -250,6 +255,8 @@ github.com/aws/aws-sdk-go-v2/service/internal/s3shared v1.13.17 h1:HfVVR1vItaG6l
 github.com/aws/aws-sdk-go-v2/service/internal/s3shared v1.13.17/go.mod h1:YqMdV+gEKCQ59NrB7rzrJdALeBIsYiVi8Inj3+KcqHI=
 github.com/aws/aws-sdk-go-v2/service/kms v1.18.13 h1:/qZYGhQ18P1DAjXzmDuBN6yxeWaj45RRpiemB7lircc=
 github.com/aws/aws-sdk-go-v2/service/kms v1.18.13/go.mod h1:DZtboupHLNr0p6qHw9r3kR8MUnN/rc4AAVmNpe2ocuU=
+github.com/aws/aws-sdk-go-v2/service/resourcegroupstaggingapi v1.13.20 h1:eOsXUswNWvA1VQ7niGYjEqCcf5uAQBGx+SnZK216P14=
+github.com/aws/aws-sdk-go-v2/service/resourcegroupstaggingapi v1.13.20/go.mod h1:+yOwSpDnUvb71cl23SK9+6lrvX/a94K7NDtgxip0UCo=
 github.com/aws/aws-sdk-go-v2/service/s3 v1.27.11 h1:3/gm/JTX9bX8CpzTgIlrtYpB3EVBDxyg/GY/QdcIEZw=
 github.com/aws/aws-sdk-go-v2/service/s3 v1.27.11/go.mod h1:fmgDANqTUCxciViKl9hb/zD5LFbvPINFRgWhDbR+vZo=
 github.com/aws/aws-sdk-go-v2/service/sso v1.11.23 h1:pwvCchFUEnlceKIgPUouBJwK81aCkQ8UDMORfeFtW10=

hack/go.mod

@@ -82,6 +82,7 @@ require (
 	github.com/aws/aws-sdk-go-v2/internal/endpoints/v2 v2.4.19 // indirect
 	github.com/aws/aws-sdk-go-v2/internal/ini v1.3.24 // indirect
 	github.com/aws/aws-sdk-go-v2/internal/v4a v1.0.14 // indirect
+	github.com/aws/aws-sdk-go-v2/service/ec2 v1.63.3 // indirect
 	github.com/aws/aws-sdk-go-v2/service/internal/accept-encoding v1.9.9 // indirect
 	github.com/aws/aws-sdk-go-v2/service/internal/checksum v1.1.18 // indirect
 	github.com/aws/aws-sdk-go-v2/service/internal/presigned-url v1.9.19 // indirect
@@ -153,6 +154,7 @@ require (
 	github.com/inconshreveable/mousetrap v1.0.1 // indirect
 	github.com/jbenet/go-context v0.0.0-20150711004518-d14ea06fba99 // indirect
 	github.com/jedisct1/go-minisign v0.0.0-20211028175153-1c139d1cc84b // indirect
+	github.com/jmespath/go-jmespath v0.4.0 // indirect
 	github.com/josharian/intern v1.0.0 // indirect
 	github.com/json-iterator/go v1.1.12 // indirect
 	github.com/kevinburke/ssh_config v0.0.0-20201106050909-4977a11b4351 // indirect

hack/go.sum

@@ -220,6 +220,8 @@ github.com/aws/aws-sdk-go-v2/internal/ini v1.3.24 h1:wj5Rwc05hvUSvKuOF29IYb9QrCL
 github.com/aws/aws-sdk-go-v2/internal/ini v1.3.24/go.mod h1:jULHjqqjDlbyTa7pfM7WICATnOv+iOhjletM3N0Xbu8=
 github.com/aws/aws-sdk-go-v2/internal/v4a v1.0.14 h1:ZSIPAkAsCCjYrhqfw2+lNzWDzxzHXEckFkTePL5RSWQ=
 github.com/aws/aws-sdk-go-v2/internal/v4a v1.0.14/go.mod h1:AyGgqiKv9ECM6IZeNQtdT8NnMvUb3/2wokeq2Fgryto=
+github.com/aws/aws-sdk-go-v2/service/ec2 v1.63.3 h1:+UHyeFhdPddRB+EkgeaKMutWiqwWrj3FIQUif3VnalM=
+github.com/aws/aws-sdk-go-v2/service/ec2 v1.63.3/go.mod h1:zul71QqzR4D1a90/5FloZiAnZ1CtuIjVH7R9MP997+A=
 github.com/aws/aws-sdk-go-v2/service/internal/accept-encoding v1.9.9 h1:Lh1AShsuIJTwMkoxVCAYPJgNG5H+eN6SmoUn8nOZ5wE=
 github.com/aws/aws-sdk-go-v2/service/internal/accept-encoding v1.9.9/go.mod h1:a9j48l6yL5XINLHLcOKInjdvknN+vWqPBxqeIDw7ktw=
 github.com/aws/aws-sdk-go-v2/service/internal/checksum v1.1.18 h1:BBYoNQt2kUZUUK4bIPsKrCcjVPUMNsgQpNAwhznK/zo=
@@ -761,7 +763,9 @@ github.com/jhump/protoreflect v1.8.2/go.mod h1:7GcYQDdMU/O/BBrl/cX6PNHpXh6cenjd8
 github.com/jhump/protoreflect v1.9.0/go.mod h1:7GcYQDdMU/O/BBrl/cX6PNHpXh6cenjd8pneu5yW7Tg=
 github.com/jmespath/go-jmespath v0.0.0-20160202185014-0b12d6b521d8/go.mod h1:Nht3zPeWKUH0NzdCt2Blrr5ys8VGpn0CEB0cQHVjt7k=
 github.com/jmespath/go-jmespath v0.0.0-20180206201540-c2b33e8439af/go.mod h1:Nht3zPeWKUH0NzdCt2Blrr5ys8VGpn0CEB0cQHVjt7k=
+github.com/jmespath/go-jmespath v0.4.0 h1:BEgLn5cpjn8UN1mAw4NjwDrS35OdebyEtFe+9YPoQUg=
 github.com/jmespath/go-jmespath v0.4.0/go.mod h1:T8mJZnbsbmF+m6zOOFylbeCJqk5+pHWvzYPziyZiYoo=
+github.com/jmespath/go-jmespath/internal/testify v1.5.1 h1:shLQSRRSCCPj3f2gpwzGwWFoC7ycTf1rcQZHOlsJ6N8=
 github.com/jmespath/go-jmespath/internal/testify v1.5.1/go.mod h1:L3OGu8Wl2/fWfCI6z80xFu9LTZmf1ZRjMHUOPmWr69U=
 github.com/jmhodges/clock v0.0.0-20160418191101-880ee4c33548 h1:dYTbLf4m0a5u0KLmPfB6mgxbcV7588bOCx79hxa5Sr4=
 github.com/joho/godotenv v1.3.0/go.mod h1:7hK45KPybAkOC6peb+G5yklZfMxEjkZhHbwpqxOKXbg=

internal/cloud/aws/metadata.go

@@ -16,7 +16,10 @@ import (
 	"github.com/aws/aws-sdk-go-v2/config"
 	"github.com/aws/aws-sdk-go-v2/feature/ec2/imds"
 	"github.com/aws/aws-sdk-go-v2/service/ec2"
-	"github.com/aws/aws-sdk-go-v2/service/ec2/types"
+	ec2Types "github.com/aws/aws-sdk-go-v2/service/ec2/types"
+	"github.com/aws/aws-sdk-go-v2/service/elasticloadbalancingv2"
+	"github.com/aws/aws-sdk-go-v2/service/resourcegroupstaggingapi"
+	tagType "github.com/aws/aws-sdk-go-v2/service/resourcegroupstaggingapi/types"
 	"github.com/edgelesssys/constellation/v2/internal/cloud"
 	"github.com/edgelesssys/constellation/v2/internal/cloud/metadata"
 	"github.com/edgelesssys/constellation/v2/internal/role"
@@ -26,6 +29,15 @@ const (
 	tagName = "Name"
 )
 
+type resourceAPI interface {
+	GetResources(context.Context, *resourcegroupstaggingapi.GetResourcesInput, ...func(*resourcegroupstaggingapi.Options)) (*resourcegroupstaggingapi.GetResourcesOutput, error)
+}
+
+type loadbalancerAPI interface {
+	DescribeLoadBalancers(ctx context.Context, params *elasticloadbalancingv2.DescribeLoadBalancersInput,
+		optFns ...func(*elasticloadbalancingv2.Options)) (*elasticloadbalancingv2.DescribeLoadBalancersOutput, error)
+}
+
 type ec2API interface {
 	DescribeInstances(context.Context, *ec2.DescribeInstancesInput, ...func(*ec2.Options)) (*ec2.DescribeInstancesOutput, error)
 }
@@ -39,6 +51,8 @@ type imdsAPI interface {
 type Metadata struct {
 	ec2               ec2API
 	imds              imdsAPI
+	loadbalancer      loadbalancerAPI
+	resourceapiClient resourceAPI
 }
 
 // New initializes a new AWS Metadata client using instance default credentials.
@@ -51,6 +65,8 @@ func New(ctx context.Context) (*Metadata, error) {
 	return &Metadata{
 		ec2:               ec2.NewFromConfig(cfg),
 		imds:              imds.New(imds.Options{}),
+		loadbalancer:      elasticloadbalancingv2.NewFromConfig(cfg),
+		resourceapiClient: resourcegroupstaggingapi.NewFromConfig(cfg),
 	}, nil
 }
 
@@ -132,23 +148,81 @@ func (m *Metadata) UID(ctx context.Context) (string, error) {
 
 // SupportsLoadBalancer returns true if the cloud provider supports load balancers.
 func (m *Metadata) SupportsLoadBalancer() bool {
-	return false
+	return true
 }
 
 // GetLoadBalancerEndpoint returns the endpoint of the load balancer.
 func (m *Metadata) GetLoadBalancerEndpoint(ctx context.Context) (string, error) {
-	panic("function *Metadata.GetLoadBalancerEndpoint not implemented")
+	uid, err := readInstanceTag(ctx, m.imds, cloud.TagUID)
+	if err != nil {
+		return "", fmt.Errorf("retrieving uid tag: %w", err)
+	}
+	arns, err := m.getARNsByTag(ctx, uid, "elasticloadbalancing:loadbalancer")
+	if err != nil {
+		return "", fmt.Errorf("retrieving load balancer ARNs: %w", err)
+	}
+	if len(arns) != 1 {
+		return "", fmt.Errorf("%d load balancers found", len(arns))
+	}
+
+	output, err := m.loadbalancer.DescribeLoadBalancers(ctx, &elasticloadbalancingv2.DescribeLoadBalancersInput{
+		LoadBalancerArns: arns,
+	})
+	if err != nil {
+		return "", fmt.Errorf("retrieving load balancer: %w", err)
+	}
+	if len(output.LoadBalancers) != 1 {
+		return "", fmt.Errorf("%d load balancers found; expected 1", len(output.LoadBalancers))
+	}
+
+	if len(output.LoadBalancers[0].AvailabilityZones) != 1 {
+		return "", fmt.Errorf("%d availability zones found; expected 1", len(output.LoadBalancers[0].AvailabilityZones))
+	}
+	if len(output.LoadBalancers[0].AvailabilityZones[0].LoadBalancerAddresses) != 1 {
+		return "", fmt.Errorf("%d load balancer addresses found; expected 1", len(output.LoadBalancers[0].AvailabilityZones[0].LoadBalancerAddresses))
+	}
+	if output.LoadBalancers[0].AvailabilityZones[0].LoadBalancerAddresses[0].IpAddress == nil {
+		return "", errors.New("load balancer address is nil")
+	}
+
+	return *output.LoadBalancers[0].AvailabilityZones[0].LoadBalancerAddresses[0].IpAddress, nil
 }
 
-// GetSubnetworkCIDR retrieves the subnetwork CIDR from cloud provider metadata.
+// getARNsByTag returns a list of ARNs that have the given tag.
-func (m *Metadata) GetSubnetworkCIDR(ctx context.Context) (string, error) {
+func (m *Metadata) getARNsByTag(ctx context.Context, uid, resourceType string) ([]string, error) {
-	panic("function *Metadata.GetSubnetworkCIDR not implemented")
+	var ARNs []string
+	resourcesReq := &resourcegroupstaggingapi.GetResourcesInput{
+		TagFilters: []tagType.TagFilter{
+			{
+				Key:    aws.String(cloud.TagUID),
+				Values: []string{uid},
+			},
+		},
+		ResourceTypeFilters: []string{resourceType},
+	}
+
+	for out, err := m.resourceapiClient.GetResources(ctx, resourcesReq); ; out, err = m.resourceapiClient.GetResources(ctx, resourcesReq) {
+		if err != nil {
+			return nil, fmt.Errorf("retrieving resources: %w", err)
+		}
+
+		for _, resource := range out.ResourceTagMappingList {
+			if resource.ResourceARN != nil {
+				ARNs = append(ARNs, *resource.ResourceARN)
+			}
+		}
+
+		if out.PaginationToken == nil || *out.PaginationToken == "" {
+			return ARNs, nil
+		}
+		resourcesReq.PaginationToken = out.PaginationToken
+	}
 }
 
-func (m *Metadata) getAllInstancesInGroup(ctx context.Context, uid string) ([]types.Instance, error) {
+func (m *Metadata) getAllInstancesInGroup(ctx context.Context, uid string) ([]ec2Types.Instance, error) {
-	var instances []types.Instance
+	var instances []ec2Types.Instance
 	instanceReq := &ec2.DescribeInstancesInput{
-		Filters: []types.Filter{
+		Filters: []ec2Types.Filter{
 			{
 				Name:   aws.String("tag:" + cloud.TagUID),
 				Values: []string{uid},
@@ -172,11 +246,11 @@ func (m *Metadata) getAllInstancesInGroup(ctx context.Context, uid string) ([]ty
 	}
 }
 
-func (m *Metadata) convertToMetadataInstance(ec2Instances []types.Instance) ([]metadata.InstanceMetadata, error) {
+func (m *Metadata) convertToMetadataInstance(ec2Instances []ec2Types.Instance) ([]metadata.InstanceMetadata, error) {
 	var instances []metadata.InstanceMetadata
 	for _, ec2Instance := range ec2Instances {
 		// ignore not running instances
-		if ec2Instance.State == nil || ec2Instance.State.Name != types.InstanceStateNameRunning {
+		if ec2Instance.State == nil || ec2Instance.State.Name != ec2Types.InstanceStateNameRunning {
 			continue
 		}
 
@@ -231,7 +305,7 @@ func readInstanceTag(ctx context.Context, api imdsAPI, tag string) (string, erro
 	return string(instanceTag), err
 }
 
-func findTag(tags []types.Tag, wantKey string) (string, error) {
+func findTag(tags []ec2Types.Tag, wantKey string) (string, error) {
 	for _, tag := range tags {
 		if tag.Key == nil || tag.Value == nil {
 			continue

internal/cloud/aws/metadata_test.go

@@ -16,7 +16,12 @@ import (
 	"github.com/aws/aws-sdk-go-v2/aws"
 	"github.com/aws/aws-sdk-go-v2/feature/ec2/imds"
 	"github.com/aws/aws-sdk-go-v2/service/ec2"
-	"github.com/aws/aws-sdk-go-v2/service/ec2/types"
+	ec2Types "github.com/aws/aws-sdk-go-v2/service/ec2/types"
+	"github.com/aws/aws-sdk-go-v2/service/elasticloadbalancingv2"
+	elbTypes "github.com/aws/aws-sdk-go-v2/service/elasticloadbalancingv2/types"
+	tagTypes "github.com/aws/aws-sdk-go-v2/service/resourcegroupstaggingapi/types"
+
+	"github.com/aws/aws-sdk-go-v2/service/resourcegroupstaggingapi"
 	"github.com/edgelesssys/constellation/v2/internal/cloud"
 	"github.com/edgelesssys/constellation/v2/internal/cloud/metadata"
 	"github.com/edgelesssys/constellation/v2/internal/role"
@@ -150,17 +155,17 @@ func TestList(t *testing.T) {
 	someErr := errors.New("failed")
 
 	successfulResp := &ec2.DescribeInstancesOutput{
-		Reservations: []types.Reservation{
+		Reservations: []ec2Types.Reservation{
 			{
-				Instances: []types.Instance{
+				Instances: []ec2Types.Instance{
 					{
-						State:            &types.InstanceState{Name: types.InstanceStateNameRunning},
+						State:            &ec2Types.InstanceState{Name: ec2Types.InstanceStateNameRunning},
 						InstanceId:       aws.String("id-1"),
 						PrivateIpAddress: aws.String("192.0.2.1"),
-						Placement: &types.Placement{
+						Placement: &ec2Types.Placement{
 							AvailabilityZone: aws.String("test-zone"),
 						},
-						Tags: []types.Tag{
+						Tags: []ec2Types.Tag{
 							{
 								Key:   aws.String(tagName),
 								Value: aws.String("name-1"),
@@ -176,13 +181,13 @@ func TestList(t *testing.T) {
 						},
 					},
 					{
-						State:            &types.InstanceState{Name: types.InstanceStateNameRunning},
+						State:            &ec2Types.InstanceState{Name: ec2Types.InstanceStateNameRunning},
 						InstanceId:       aws.String("id-2"),
 						PrivateIpAddress: aws.String("192.0.2.2"),
-						Placement: &types.Placement{
+						Placement: &ec2Types.Placement{
 							AvailabilityZone: aws.String("test-zone"),
 						},
-						Tags: []types.Tag{
+						Tags: []ec2Types.Tag{
 							{
 								Key:   aws.String(tagName),
 								Value: aws.String("name-2"),
@@ -240,17 +245,17 @@ func TestList(t *testing.T) {
 			},
 			ec2: &stubEC2{
 				describeInstancesResp1: &ec2.DescribeInstancesOutput{
-					Reservations: []types.Reservation{
+					Reservations: []ec2Types.Reservation{
 						{
-							Instances: []types.Instance{
+							Instances: []ec2Types.Instance{
 								{
-									State:            &types.InstanceState{Name: types.InstanceStateNameRunning},
+									State:            &ec2Types.InstanceState{Name: ec2Types.InstanceStateNameRunning},
 									InstanceId:       aws.String("id-3"),
 									PrivateIpAddress: aws.String("192.0.2.3"),
-									Placement: &types.Placement{
+									Placement: &ec2Types.Placement{
 										AvailabilityZone: aws.String("test-zone-2"),
 									},
-									Tags: []types.Tag{
+									Tags: []ec2Types.Tag{
 										{
 											Key:   aws.String(tagName),
 											Value: aws.String("name-3"),
@@ -330,22 +335,223 @@ func TestList(t *testing.T) {
 	}
 }
 
+func TestGetLoadBalancerEndpoint(t *testing.T) {
+	lbAddr := "192.0.2.1"
+	someErr := errors.New("some error")
+
+	testCases := map[string]struct {
+		imds         *stubIMDS
+		loadbalancer *stubLoadbalancer
+		resourceapi  *stubResourceGroupTagging
+		wantAddr     string
+		wantErr      bool
+	}{
+		"success retrieving loadbalancer endpoint": {
+			imds: &stubIMDS{
+				tags: map[string]string{
+					cloud.TagUID: "uid",
+				},
+			},
+			loadbalancer: &stubLoadbalancer{
+				describeLoadBalancersOut: &elasticloadbalancingv2.DescribeLoadBalancersOutput{
+					LoadBalancers: []elbTypes.LoadBalancer{
+						{
+							AvailabilityZones: []elbTypes.AvailabilityZone{
+								{
+									LoadBalancerAddresses: []elbTypes.LoadBalancerAddress{
+										{
+											IpAddress: aws.String(lbAddr),
+										},
+									},
+								},
+							},
+						},
+					},
+				},
+			},
+			resourceapi: &stubResourceGroupTagging{
+				getResourcesOut1: &resourcegroupstaggingapi.GetResourcesOutput{
+					ResourceTagMappingList: []tagTypes.ResourceTagMapping{
+						{
+							ResourceARN: aws.String("arn:aws:elasticloadbalancing:us-east-1:123456789012:loadbalancer/app/test-loadbalancer/50dc6c495c0c9188"),
+						},
+					},
+				},
+			},
+			wantAddr: lbAddr,
+		},
+		"too many ARNs": {
+			imds: &stubIMDS{
+				tags: map[string]string{
+					cloud.TagUID: "uid",
+				},
+			},
+			loadbalancer: &stubLoadbalancer{
+				describeLoadBalancersOut: &elasticloadbalancingv2.DescribeLoadBalancersOutput{
+					LoadBalancers: []elbTypes.LoadBalancer{
+						{
+							AvailabilityZones: []elbTypes.AvailabilityZone{
+								{
+									LoadBalancerAddresses: []elbTypes.LoadBalancerAddress{
+										{
+											IpAddress: aws.String(lbAddr),
+										},
+									},
+								},
+							},
+						},
+					},
+				},
+			},
+			resourceapi: &stubResourceGroupTagging{
+				getResourcesOut1: &resourcegroupstaggingapi.GetResourcesOutput{
+					ResourceTagMappingList: []tagTypes.ResourceTagMapping{
+						{
+							ResourceARN: aws.String("arn:aws:elasticloadbalancing:us-east-1:123456789012:loadbalancer/app/test-loadbalancer/50dc6c495c0c9188"),
+						},
+						{
+							ResourceARN: aws.String("arn:aws:elasticloadbalancing:us-east-1:123456789012:loadbalancer/app/test-loadbalancer/50dc6c495c0c9188"),
+						},
+					},
+				},
+			},
+			wantErr: true,
+		},
+		"too many ARNs (paged)": {
+			imds: &stubIMDS{
+				tags: map[string]string{
+					cloud.TagUID: "uid",
+				},
+			},
+			loadbalancer: &stubLoadbalancer{
+				describeLoadBalancersOut: &elasticloadbalancingv2.DescribeLoadBalancersOutput{
+					LoadBalancers: []elbTypes.LoadBalancer{
+						{
+							AvailabilityZones: []elbTypes.AvailabilityZone{
+								{
+									LoadBalancerAddresses: []elbTypes.LoadBalancerAddress{
+										{
+											IpAddress: aws.String(lbAddr),
+										},
+									},
+								},
+							},
+						},
+					},
+				},
+			},
+			resourceapi: &stubResourceGroupTagging{
+				getResourcesOut1: &resourcegroupstaggingapi.GetResourcesOutput{
+					ResourceTagMappingList: []tagTypes.ResourceTagMapping{
+						{
+							ResourceARN: aws.String("arn:aws:elasticloadbalancing:us-east-1:123456789012:loadbalancer/app/test-loadbalancer/50dc6c495c0c9188"),
+						},
+					},
+					PaginationToken: aws.String("token"),
+				},
+				getResourcesOut2: &resourcegroupstaggingapi.GetResourcesOutput{
+					ResourceTagMappingList: []tagTypes.ResourceTagMapping{
+						{
+							ResourceARN: aws.String("arn:aws:elasticloadbalancing:us-east-1:123456789012:loadbalancer/app/test-loadbalancer/50dc6c495c0c9188"),
+						},
+					},
+				},
+			},
+			wantErr: true,
+		},
+		"loadbalancer has no availability zones": {
+			imds: &stubIMDS{
+				tags: map[string]string{
+					cloud.TagUID: "uid",
+				},
+			},
+			loadbalancer: &stubLoadbalancer{
+				describeLoadBalancersOut: &elasticloadbalancingv2.DescribeLoadBalancersOutput{
+					LoadBalancers: []elbTypes.LoadBalancer{
+						{
+							AvailabilityZones: []elbTypes.AvailabilityZone{},
+						},
+					},
+				},
+			},
+			resourceapi: &stubResourceGroupTagging{
+				getResourcesOut1: &resourcegroupstaggingapi.GetResourcesOutput{
+					ResourceTagMappingList: []tagTypes.ResourceTagMapping{
+						{
+							ResourceARN: aws.String("arn:aws:elasticloadbalancing:us-east-1:123456789012:loadbalancer/app/test-loadbalancer/50dc6c495c0c9188"),
+						},
+					},
+				},
+			},
+			wantErr: true,
+		},
+		"failure to get resources by tag": {
+			imds: &stubIMDS{
+				tags: map[string]string{
+					cloud.TagUID: "uid",
+				},
+			},
+			loadbalancer: &stubLoadbalancer{
+				describeLoadBalancersOut: &elasticloadbalancingv2.DescribeLoadBalancersOutput{
+					LoadBalancers: []elbTypes.LoadBalancer{
+						{
+							AvailabilityZones: []elbTypes.AvailabilityZone{
+								{
+									LoadBalancerAddresses: []elbTypes.LoadBalancerAddress{
+										{
+											IpAddress: aws.String(lbAddr),
+										},
+									},
+								},
+							},
+						},
+					},
+				},
+			},
+			resourceapi: &stubResourceGroupTagging{
+				getResourcesErr: someErr,
+			},
+			wantErr: true,
+		},
+	}
+
+	for name, tc := range testCases {
+		t.Run(name, func(t *testing.T) {
+			assert := assert.New(t)
+			m := &Metadata{
+				imds:              tc.imds,
+				loadbalancer:      tc.loadbalancer,
+				resourceapiClient: tc.resourceapi,
+			}
+
+			endpoint, err := m.GetLoadBalancerEndpoint(context.Background())
+			if tc.wantErr {
+				assert.Error(err)
+				return
+			}
+
+			assert.NoError(err)
+			assert.Equal(tc.wantAddr, endpoint)
+		})
+	}
+}
+
 func TestConvertToMetadataInstance(t *testing.T) {
 	testCases := map[string]struct {
-		in            []types.Instance
+		in            []ec2Types.Instance
 		wantInstances []metadata.InstanceMetadata
 		wantErr       bool
 	}{
 		"success": {
-			in: []types.Instance{
+			in: []ec2Types.Instance{
 				{
-					State:            &types.InstanceState{Name: types.InstanceStateNameRunning},
+					State:            &ec2Types.InstanceState{Name: ec2Types.InstanceStateNameRunning},
 					InstanceId:       aws.String("id-1"),
 					PrivateIpAddress: aws.String("192.0.2.1"),
-					Placement: &types.Placement{
+					Placement: &ec2Types.Placement{
 						AvailabilityZone: aws.String("test-zone"),
 					},
-					Tags: []types.Tag{
+					Tags: []ec2Types.Tag{
 						{
 							Key:   aws.String(tagName),
 							Value: aws.String("name-1"),
@@ -367,12 +573,12 @@ func TestConvertToMetadataInstance(t *testing.T) {
 			},
 		},
 		"fallback to instance ID": {
-			in: []types.Instance{
+			in: []ec2Types.Instance{
 				{
-					State:            &types.InstanceState{Name: types.InstanceStateNameRunning},
+					State:            &ec2Types.InstanceState{Name: ec2Types.InstanceStateNameRunning},
 					InstanceId:       aws.String("id-1"),
 					PrivateIpAddress: aws.String("192.0.2.1"),
-					Tags: []types.Tag{
+					Tags: []ec2Types.Tag{
 						{
 							Key:   aws.String(tagName),
 							Value: aws.String("name-1"),
@@ -395,24 +601,24 @@ func TestConvertToMetadataInstance(t *testing.T) {
 			},
 		},
 		"non running instances are ignored": {
-			in: []types.Instance{
+			in: []ec2Types.Instance{
 				{
-					State: &types.InstanceState{Name: types.InstanceStateNameStopped},
+					State: &ec2Types.InstanceState{Name: ec2Types.InstanceStateNameStopped},
 				},
 				{
-					State: &types.InstanceState{Name: types.InstanceStateNameTerminated},
+					State: &ec2Types.InstanceState{Name: ec2Types.InstanceStateNameTerminated},
 				},
 			},
 		},
 		"no instance ID": {
-			in: []types.Instance{
+			in: []ec2Types.Instance{
 				{
-					State:            &types.InstanceState{Name: types.InstanceStateNameRunning},
+					State:            &ec2Types.InstanceState{Name: ec2Types.InstanceStateNameRunning},
 					PrivateIpAddress: aws.String("192.0.2.1"),
-					Placement: &types.Placement{
+					Placement: &ec2Types.Placement{
 						AvailabilityZone: aws.String("test-zone"),
 					},
-					Tags: []types.Tag{
+					Tags: []ec2Types.Tag{
 						{
 							Key:   aws.String(tagName),
 							Value: aws.String("name-1"),
@@ -427,14 +633,14 @@ func TestConvertToMetadataInstance(t *testing.T) {
 			wantErr: true,
 		},
 		"no private IP": {
-			in: []types.Instance{
+			in: []ec2Types.Instance{
 				{
-					State:      &types.InstanceState{Name: types.InstanceStateNameRunning},
+					State:      &ec2Types.InstanceState{Name: ec2Types.InstanceStateNameRunning},
 					InstanceId: aws.String("id-1"),
-					Placement: &types.Placement{
+					Placement: &ec2Types.Placement{
 						AvailabilityZone: aws.String("test-zone"),
 					},
-					Tags: []types.Tag{
+					Tags: []ec2Types.Tag{
 						{
 							Key:   aws.String(tagName),
 							Value: aws.String("name-1"),
@@ -449,15 +655,15 @@ func TestConvertToMetadataInstance(t *testing.T) {
 			wantErr: true,
 		},
 		"missing name tag": {
-			in: []types.Instance{
+			in: []ec2Types.Instance{
 				{
-					State:            &types.InstanceState{Name: types.InstanceStateNameRunning},
+					State:            &ec2Types.InstanceState{Name: ec2Types.InstanceStateNameRunning},
 					InstanceId:       aws.String("id-1"),
 					PrivateIpAddress: aws.String("192.0.2.1"),
-					Placement: &types.Placement{
+					Placement: &ec2Types.Placement{
 						AvailabilityZone: aws.String("test-zone"),
 					},
-					Tags: []types.Tag{
+					Tags: []ec2Types.Tag{
 						{
 							Key:   aws.String(cloud.TagRole),
 							Value: aws.String("controlplane"),
@@ -468,15 +674,15 @@ func TestConvertToMetadataInstance(t *testing.T) {
 			wantErr: true,
 		},
 		"missing role tag": {
-			in: []types.Instance{
+			in: []ec2Types.Instance{
 				{
-					State:            &types.InstanceState{Name: types.InstanceStateNameRunning},
+					State:            &ec2Types.InstanceState{Name: ec2Types.InstanceStateNameRunning},
 					InstanceId:       aws.String("id-1"),
 					PrivateIpAddress: aws.String("192.0.2.1"),
-					Placement: &types.Placement{
+					Placement: &ec2Types.Placement{
 						AvailabilityZone: aws.String("test-zone"),
 					},
-					Tags: []types.Tag{
+					Tags: []ec2Types.Tag{
 						{
 							Key:   aws.String(tagName),
 							Value: aws.String("name-1"),
@@ -542,3 +748,33 @@ func (s *stubEC2) DescribeInstances(_ context.Context, in *ec2.DescribeInstances
 	}
 	return s.describeInstancesResp2, s.describeInstancesErr
 }
+
+type stubLoadbalancer struct {
+	describeLoadBalancersErr error
+	describeLoadBalancersOut *elasticloadbalancingv2.DescribeLoadBalancersOutput
+}
+
+func (s *stubLoadbalancer) DescribeLoadBalancers(_ context.Context,
+	in *elasticloadbalancingv2.DescribeLoadBalancersInput,
+	_ ...func(*elasticloadbalancingv2.Options)) (
+	*elasticloadbalancingv2.DescribeLoadBalancersOutput, error,
+) {
+	return s.describeLoadBalancersOut, s.describeLoadBalancersErr
+}
+
+type stubResourceGroupTagging struct {
+	getResourcesErr  error
+	getResourcesOut1 *resourcegroupstaggingapi.GetResourcesOutput
+	getResourcesOut2 *resourcegroupstaggingapi.GetResourcesOutput
+}
+
+func (s *stubResourceGroupTagging) GetResources(_ context.Context,
+	in *resourcegroupstaggingapi.GetResourcesInput,
+	_ ...func(*resourcegroupstaggingapi.Options)) (
+	*resourcegroupstaggingapi.GetResourcesOutput, error,
+) {
+	if in.PaginationToken == nil {
+		return s.getResourcesOut1, s.getResourcesErr
+	}
+	return s.getResourcesOut2, s.getResourcesErr
+}