Add admission controller

config/rbac/role.yaml

@@ -32,6 +32,7 @@ rules:
   verbs:
   - create
   - get
+  - list
   - watch
 - apiGroups:
   - cluster.x-k8s.io

controllers/infrastructure/byoadmission_controller.go

@@ -0,0 +1,96 @@
+// Copyright 2022 VMware, Inc. All Rights Reserved.
+// SPDX-License-Identifier: Apache-2.0
+
+package controllers
+
+import (
+	"context"
+	"fmt"
+	"strings"
+
+	certv1 "k8s.io/api/certificates/v1"
+	apierrors "k8s.io/apimachinery/pkg/api/errors"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	clientset "k8s.io/client-go/kubernetes"
+	ctrl "sigs.k8s.io/controller-runtime"
+	"sigs.k8s.io/controller-runtime/pkg/event"
+	"sigs.k8s.io/controller-runtime/pkg/log"
+	"sigs.k8s.io/controller-runtime/pkg/predicate"
+	"sigs.k8s.io/controller-runtime/pkg/reconcile"
+)
+
+// ByoAdmissionReconciler reconciles a ByoAdmission object
+type ByoAdmissionReconciler struct {
+	ClientSet clientset.Interface
+}
+
+//+kubebuilder:rbac:groups=infrastructure.cluster.x-k8s.io,resources=byohosts,verbs=get;list;watch;create;update;patch;delete
+//+kubebuilder:rbac:groups=infrastructure.cluster.x-k8s.io,resources=byohosts/status,verbs=get;update;patch
+//+kubebuilder:rbac:groups=infrastructure.cluster.x-k8s.io,resources=byohosts/finalizers,verbs=update
+//+kubebuilder:rbac:groups=certificates.k8s.io,resources=certificatesigningrequests,verbs=create;get;list;watch
+
+// Reconcile continuosuly checks for CSRs and approves them
+func (r *ByoAdmissionReconciler) Reconcile(ctx context.Context, req ctrl.Request) (ctrl.Result, error) {
+	var err error
+	logger := log.FromContext(ctx)
+	logger.Info("Reconcile request received", "object", req.NamespacedName)
+
+	// Fetch the CSR from the api-server
+	csr, err := r.ClientSet.CertificatesV1().CertificateSigningRequests().Get(ctx, req.NamespacedName.Name, metav1.GetOptions{})
+	if err != nil {
+		if apierrors.IsNotFound(err) {
+			logger.Error(err, "CertificateSigningRequest not found, won't reconcile")
+			return reconcile.Result{}, nil
+		}
+		return reconcile.Result{}, err
+	}
+
+	// Check if the CSR is already approved or denied
+	if checkCSRCondition(csr.Status.Conditions, certv1.CertificateApproved) {
+		return ctrl.Result{}, fmt.Errorf("CertificateSigningRequest %s is already approved", csr.Name)
+	} else if checkCSRCondition(csr.Status.Conditions, certv1.CertificateDenied) {
+		return ctrl.Result{}, fmt.Errorf("CertificateSigningRequest %s is already denied", csr.Name)
+	}
+
+	// Update the CSR to the "Approved" condition
+	csr.Status.Conditions = append(csr.Status.Conditions, certv1.CertificateSigningRequestCondition{
+		Type:   certv1.CertificateApproved,
+		Reason: "Approved by ByoAdmission Controller",
+	})
+
+	// Approve the CSR
+	logger.Info("Approving CSR", "object", req.NamespacedName)
+	_, err = r.ClientSet.CertificatesV1().CertificateSigningRequests().UpdateApproval(ctx, csr.Name, csr, metav1.UpdateOptions{})
+	if err != nil {
+		return reconcile.Result{}, err
+	}
+
+	logger.Info("CSR Approved", "object", req.NamespacedName)
+
+	return ctrl.Result{}, nil
+}
+
+// Check if the CSR has the given condition.
+func checkCSRCondition(conditions []certv1.CertificateSigningRequestCondition, conditionType certv1.RequestConditionType) bool {
+	for _, condition := range conditions {
+		if condition.Type == conditionType {
+			return true
+		}
+	}
+	return false
+}
+
+// SetupWithManager sets up the controller with the Manager.
+func (r *ByoAdmissionReconciler) SetupWithManager(mgr ctrl.Manager) error {
+	return ctrl.NewControllerManagedBy(mgr).
+		For(&certv1.CertificateSigningRequest{}).WithEventFilter(
+		// watch only BYOH created CSRs
+		predicate.Funcs{
+			CreateFunc: func(e event.CreateEvent) bool {
+				return strings.HasPrefix(e.Object.GetName(), "byoh-csr-")
+			},
+			UpdateFunc: func(e event.UpdateEvent) bool {
+				return strings.HasPrefix(e.ObjectOld.GetName(), "byoh-csr-")
+			}}).
+		Complete(r)
+}

controllers/infrastructure/byoadmission_controller_test.go

@@ -0,0 +1,98 @@
+// Copyright 2021 VMware, Inc. All Rights Reserved.
+// SPDX-License-Identifier: Apache-2.0
+
+package controllers_test
+
+import (
+	"context"
+	"fmt"
+
+	. "github.com/onsi/ginkgo"
+	. "github.com/onsi/gomega"
+	"github.com/vmware-tanzu/cluster-api-provider-bringyourownhost/test/builder"
+	certv1 "k8s.io/api/certificates/v1"
+	v1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/types"
+	"sigs.k8s.io/controller-runtime/pkg/reconcile"
+)
+
+var _ = Describe("Controllers/ByoadmissionController", func() {
+	var (
+		ctx context.Context
+		err error
+		CSR *certv1.CertificateSigningRequest
+	)
+
+	It("should return error for non-existent CSR", func() {
+		// Call Reconcile method for a non-existing CSR
+		objectKey := types.NamespacedName{Name: defaultByoHostName}
+		_, err = byoAdmissionReconciler.Reconcile(ctx, reconcile.Request{NamespacedName: objectKey})
+		Expect(err).To(BeNil())
+	})
+
+	Context("When a CSR is created", func() {
+		BeforeEach(func() {
+			ctx = context.Background()
+
+			// Create a CSR resource for each test
+			CSR, err = builder.CertificateSigningRequest(defaultByoHostName, "test-cn", "test-org", 2048).Build()
+			Expect(err).NotTo(HaveOccurred())
+		})
+
+		It("should approve the Byoh CSR", func() {
+			// Create a dummy CSR request
+			_, err = clientSetFake.CertificatesV1().CertificateSigningRequests().Create(ctx, CSR, v1.CreateOptions{})
+			Expect(err).ToNot(HaveOccurred())
+
+			// Call Reconcile method
+			objectKey := types.NamespacedName{Name: defaultByoHostName}
+			_, err = byoAdmissionReconciler.Reconcile(ctx, reconcile.Request{NamespacedName: objectKey})
+			Expect(err).ShouldNot(HaveOccurred())
+
+			// Fetch the updated CSR
+			var updateByohCSR *certv1.CertificateSigningRequest
+			updateByohCSR, err = clientSetFake.CertificatesV1().CertificateSigningRequests().Get(ctx, defaultByoHostName, v1.GetOptions{})
+			Expect(err).ToNot(HaveOccurred())
+			Expect(updateByohCSR.Status.Conditions).Should(ContainElement(certv1.CertificateSigningRequestCondition{
+				Type:   certv1.CertificateApproved,
+				Reason: "Approved by ByoAdmission Controller",
+			}))
+		})
+
+		It("should not approve a denied CSR", func() {
+			// Create a fake denied CSR request
+			CSR.Status.Conditions = append(CSR.Status.Conditions, certv1.CertificateSigningRequestCondition{
+				Type: certv1.CertificateDenied,
+			})
+
+			_, err = clientSetFake.CertificatesV1().CertificateSigningRequests().Create(ctx, CSR, v1.CreateOptions{})
+			Expect(err).ToNot(HaveOccurred())
+
+			// Call Reconcile method
+			objectKey := types.NamespacedName{Name: defaultByoHostName}
+			_, err = byoAdmissionReconciler.Reconcile(ctx, reconcile.Request{NamespacedName: objectKey})
+			Expect(err).To(Equal(fmt.Errorf("CertificateSigningRequest %s is already denied", CSR.Name)))
+		})
+
+		It("should not approve an already approved CSR", func() {
+			// Create a fake approved CSR request
+			CSR.Status.Conditions = append(CSR.Status.Conditions, certv1.CertificateSigningRequestCondition{
+				Type: certv1.CertificateApproved,
+			})
+
+			_, err = clientSetFake.CertificatesV1().CertificateSigningRequests().Create(ctx, CSR, v1.CreateOptions{})
+			Expect(err).ToNot(HaveOccurred())
+
+			// Call Reconcile method
+			objectKey := types.NamespacedName{Name: defaultByoHostName}
+			_, err = byoAdmissionReconciler.Reconcile(ctx, reconcile.Request{NamespacedName: objectKey})
+			Expect(err).To(Equal(fmt.Errorf("CertificateSigningRequest %s is already approved", CSR.Name)))
+		})
+
+		AfterEach(func() {
+			Expect(clientSetFake.CertificatesV1().CertificateSigningRequests().Delete(ctx, defaultByoHostName, v1.DeleteOptions{})).ShouldNot(HaveOccurred())
+		})
+
+	})
+
+})

controllers/infrastructure/suite_test.go

@@ -28,6 +28,7 @@ import (
 
 	//+kubebuilder:scaffold:imports
 
+	fakeclientset "k8s.io/client-go/kubernetes/fake"
 	clusterv1 "sigs.k8s.io/cluster-api/api/v1beta1"
 	bootstrapv1 "sigs.k8s.io/cluster-api/bootstrap/kubeadm/api/v1beta1"
 	"sigs.k8s.io/cluster-api/controllers/remote"
@@ -38,24 +39,26 @@ import (
 // http://onsi.github.io/ginkgo/ to learn more about Ginkgo.
 
 var (
-	testEnv               *envtest.Environment
-	clientFake            client.Client
-	reconciler            *controllers.ByoMachineReconciler
-	byoClusterReconciler  *controllers.ByoClusterReconciler
-	recorder              *record.FakeRecorder
-	byoCluster            *infrastructurev1beta1.ByoCluster
-	capiCluster           *clusterv1.Cluster
-	defaultClusterName    = "my-cluster"
-	defaultNodeName       = "my-host"
-	defaultByoHostName    = "my-host"
-	defaultMachineName    = "my-machine"
-	defaultByoMachineName = "my-byomachine"
-	defaultNamespace      = "default"
-	fakeBootstrapSecret   = "fakeBootstrapSecret"
-	k8sManager            ctrl.Manager
-	cfg                   *rest.Config
-	ctx                   context.Context
-	cancel                context.CancelFunc
+	testEnv                *envtest.Environment
+	clientFake             client.Client
+	clientSetFake          = fakeclientset.NewSimpleClientset()
+	reconciler             *controllers.ByoMachineReconciler
+	byoClusterReconciler   *controllers.ByoClusterReconciler
+	byoAdmissionReconciler *controllers.ByoAdmissionReconciler
+	recorder               *record.FakeRecorder
+	byoCluster             *infrastructurev1beta1.ByoCluster
+	capiCluster            *clusterv1.Cluster
+	defaultClusterName     = "my-cluster"
+	defaultNodeName        = "my-host"
+	defaultByoHostName     = "my-host"
+	defaultMachineName     = "my-machine"
+	defaultByoMachineName  = "my-byomachine"
+	defaultNamespace       = "default"
+	fakeBootstrapSecret    = "fakeBootstrapSecret"
+	k8sManager             ctrl.Manager
+	cfg                    *rest.Config
+	ctx                    context.Context
+	cancel                 context.CancelFunc
 )
 
 func TestAPIs(t *testing.T) {
@@ -132,6 +135,12 @@ var _ = BeforeSuite(func() {
 	err = byoClusterReconciler.SetupWithManager(k8sManager)
 	Expect(err).NotTo(HaveOccurred())
 
+	byoAdmissionReconciler = &controllers.ByoAdmissionReconciler{
+		ClientSet: clientSetFake,
+	}
+	err = byoAdmissionReconciler.SetupWithManager(k8sManager)
+	Expect(err).NotTo(HaveOccurred())
+
 	go func() {
 		err = k8sManager.GetCache().Start(ctx)
 		Expect(err).NotTo(HaveOccurred())

main.go

@@ -17,6 +17,7 @@ import (
 	admissionv1beta1 "k8s.io/api/admission/v1beta1"
 	"k8s.io/apimachinery/pkg/runtime"
 	utilruntime "k8s.io/apimachinery/pkg/util/runtime"
+	clientset "k8s.io/client-go/kubernetes"
 	clientgoscheme "k8s.io/client-go/kubernetes/scheme"
 	ctrl "sigs.k8s.io/controller-runtime"
 	"sigs.k8s.io/controller-runtime/pkg/healthz"
@@ -32,8 +33,11 @@ import (
 )
 
 var (
-	scheme   = runtime.NewScheme()
-	setupLog = ctrl.Log.WithName("setup")
+	scheme               = runtime.NewScheme()
+	setupLog             = ctrl.Log.WithName("setup")
+	metricsAddr          string
+	enableLeaderElection bool
+	probeAddr            string
 )
 
 func init() {
@@ -47,16 +51,16 @@ func init() {
 	utilruntime.Must(admissionv1beta1.AddToScheme(scheme))
 }
 
-func main() {
-	var metricsAddr string
-	var enableLeaderElection bool
-	var probeAddr string
+func setFlags() {
 	flag.StringVar(&metricsAddr, "metrics-addr", ":8080", "The address the metric endpoint binds to.")
 	flag.BoolVar(&enableLeaderElection, "enable-leader-election", false,
 		"Enable leader election for controller manager. Enabling this will ensure there is only one active controller manager.")
 	flag.StringVar(&probeAddr, "health-probe-bind-address", ":8081", "The address the probe endpoint binds to.")
 	flag.Parse()
+}
 
+func main() {
+	setFlags()
 	ctrl.SetLogger(klogr.New())
 
 	mgr, err := ctrl.NewManager(ctrl.GetConfigOrDie(), ctrl.Options{
@@ -118,6 +122,12 @@ func main() {
 		setupLog.Error(err, "unable to create controller", "controller", "ByoCluster")
 		os.Exit(1)
 	}
+	if err = (&byohcontrollers.ByoAdmissionReconciler{
+		ClientSet: clientset.NewForConfigOrDie(ctrl.GetConfigOrDie()),
+	}).SetupWithManager(mgr); err != nil {
+		setupLog.Error(err, "unable to create controller", "controller", "ByoAdmission")
+		os.Exit(1)
+	}
 
 	if err = (&infrastructurev1beta1.ByoCluster{}).SetupWebhookWithManager(mgr); err != nil {
 		setupLog.Error(err, "unable to create webhook", "webhook", "ByoCluster")

test/e2e/e2e_suite_test.go

@@ -17,6 +17,7 @@ import (
 	. "github.com/onsi/gomega"
 	"github.com/onsi/gomega/gexec"
 	infraproviderv1 "github.com/vmware-tanzu/cluster-api-provider-bringyourownhost/apis/infrastructure/v1beta1"
+	certv1 "k8s.io/api/certificates/v1"
 	corev1 "k8s.io/api/core/v1"
 	"k8s.io/apimachinery/pkg/runtime"
 	clusterv1 "sigs.k8s.io/cluster-api/api/v1beta1"
@@ -151,6 +152,7 @@ var _ = SynchronizedAfterSuite(func() {
 func initScheme() *runtime.Scheme {
 	sc := runtime.NewScheme()
 	framework.TryAddDefaultSchemes(sc)
+	Expect(certv1.AddToScheme(sc)).NotTo(HaveOccurred())
 	Expect(infraproviderv1.AddToScheme(sc)).NotTo(HaveOccurred())
 	return sc
 }