separate RootCAConfigMap from BoundServiceAccountTokenVolume

cmd/kube-controller-manager/app/certificates.go

@@ -193,7 +193,7 @@ func startCSRCleanerController(ctx ControllerContext) (http.Handler, bool, error
 }
 
 func startRootCACertPublisher(ctx ControllerContext) (http.Handler, bool, error) {
-	if !utilfeature.DefaultFeatureGate.Enabled(features.BoundServiceAccountTokenVolume) {
+	if !utilfeature.DefaultFeatureGate.Enabled(features.RootCAConfigMap) {
 		return nil, false, nil
 	}
 

pkg/controller/certificates/rootcacertpublisher/publisher.go

@@ -200,6 +200,8 @@ func (c *Publisher) syncNamespace(ns string) error {
 		return nil
 	}
 
+	// copy so we don't modify the cache's instance of the configmap
+	cm = cm.DeepCopy()
 	cm.Data = data
 
 	_, err = c.client.CoreV1().ConfigMaps(ns).Update(context.TODO(), cm, metav1.UpdateOptions{})

pkg/features/kube_features.go

@@ -643,6 +643,14 @@ const (
 	// Add support for the HPA to scale based on metrics from individual containers
 	// in target pods
 	HPAContainerMetrics featuregate.Feature = "HPAContainerMetrics"
+
+	// owner: @zshihang
+	// alpha: v1.13
+	// beta: v1.20
+	//
+	// Allows kube-controller-manager to publish kube-root-ca.crt configmap to
+	// every namespace. This feature is a prerequisite of BoundServiceAccountTokenVolume.
+	RootCAConfigMap featuregate.Feature = "RootCAConfigMap"
 )
 
 func init() {
@@ -740,6 +748,7 @@ var defaultKubernetesFeatureGates = map[featuregate.Feature]featuregate.FeatureS
 	WinDSR:                                         {Default: false, PreRelease: featuregate.Alpha},
 	DisableAcceleratorUsageMetrics:                 {Default: true, PreRelease: featuregate.Beta},
 	HPAContainerMetrics:                            {Default: false, PreRelease: featuregate.Alpha},
+	RootCAConfigMap:                                {Default: true, PreRelease: featuregate.Beta},
 
 	// inherited features from generic apiserver, relisted here to get a conflict if it is changed
 	// unintentionally on either side:

pkg/kubeapiserver/options/authentication.go

@@ -199,6 +199,9 @@ func (o *BuiltInAuthenticationOptions) Validate() []error {
 		}
 	}
 	if o.ServiceAccounts != nil && utilfeature.DefaultFeatureGate.Enabled(features.BoundServiceAccountTokenVolume) {
+		if !utilfeature.DefaultFeatureGate.Enabled(features.RootCAConfigMap) {
+			allErrors = append(allErrors, errors.New("BoundServiceAccountTokenVolume feature depends on RootCAConfigMap feature, but RootCAConfigMap features is not enabled"))
+		}
 		if len(o.ServiceAccounts.Issuer) == 0 {
 			allErrors = append(allErrors, errors.New("service-account-issuer is a required flag when BoundServiceAccountTokenVolume is enabled"))
 		}

plugin/pkg/auth/authorizer/rbac/bootstrappolicy/controller_policy.go

@@ -402,7 +402,7 @@ func buildControllerRoles() ([]rbacv1.ClusterRole, []rbacv1.ClusterRoleBinding)
 		})
 	}
 
-	if utilfeature.DefaultFeatureGate.Enabled(features.BoundServiceAccountTokenVolume) {
+	if utilfeature.DefaultFeatureGate.Enabled(features.RootCAConfigMap) {
 		addControllerRole(&controllerRoles, &controllerRoleBindings, rbacv1.ClusterRole{
 			ObjectMeta: metav1.ObjectMeta{Name: saRolePrefix + "root-ca-cert-publisher"},
 			Rules: []rbacv1.PolicyRule{

plugin/pkg/auth/authorizer/rbac/bootstrappolicy/testdata/controller-role-bindings.yaml

@@ -391,6 +391,23 @@ items:
   - kind: ServiceAccount
     name: resourcequota-controller
     namespace: kube-system
+- apiVersion: rbac.authorization.k8s.io/v1
+  kind: ClusterRoleBinding
+  metadata:
+    annotations:
+      rbac.authorization.kubernetes.io/autoupdate: "true"
+    creationTimestamp: null
+    labels:
+      kubernetes.io/bootstrapping: rbac-defaults
+    name: system:controller:root-ca-cert-publisher
+  roleRef:
+    apiGroup: rbac.authorization.k8s.io
+    kind: ClusterRole
+    name: system:controller:root-ca-cert-publisher
+  subjects:
+  - kind: ServiceAccount
+    name: root-ca-cert-publisher
+    namespace: kube-system
 - apiVersion: rbac.authorization.k8s.io/v1
   kind: ClusterRoleBinding
   metadata:

plugin/pkg/auth/authorizer/rbac/bootstrappolicy/testdata/controller-roles.yaml

@@ -1195,6 +1195,32 @@ items:
     - create
     - patch
     - update
+- apiVersion: rbac.authorization.k8s.io/v1
+  kind: ClusterRole
+  metadata:
+    annotations:
+      rbac.authorization.kubernetes.io/autoupdate: "true"
+    creationTimestamp: null
+    labels:
+      kubernetes.io/bootstrapping: rbac-defaults
+    name: system:controller:root-ca-cert-publisher
+  rules:
+  - apiGroups:
+    - ""
+    resources:
+    - configmaps
+    verbs:
+    - create
+    - update
+  - apiGroups:
+    - ""
+    - events.k8s.io
+    resources:
+    - events
+    verbs:
+    - create
+    - patch
+    - update
 - apiVersion: rbac.authorization.k8s.io/v1
   kind: ClusterRole
   metadata:

test/cmd/apply.sh

@@ -310,8 +310,8 @@ __EOF__
   kubectl delete -f hack/testdata/multi-resource-1.yaml "${kube_flags[@]:?}"
 
   ## kubectl apply multiple resources with one failure during builder phase.
-  # Pre-Condition: No configmaps
+  # Pre-Condition: No configmaps with name=foo
-  kube::test::get_object_assert configmaps "{{range.items}}{{${id_field:?}}}:{{end}}" ''
+  kube::test::get_object_assert 'configmaps --field-selector=metadata.name=foo' "{{range.items}}{{${id_field:?}}}:{{end}}" ''
   # Apply a configmap and a bogus custom resource.
   output_message=$(! kubectl apply -f hack/testdata/multi-resource-2.yaml 2>&1 "${kube_flags[@]:?}")
   # Should be error message from bogus custom resource.

test/cmd/create.sh

@@ -134,8 +134,8 @@ run_kubectl_create_kustomization_directory_tests() {
   set -o errexit
 
   ## kubectl create -k <dir> for kustomization directory
-  # Pre-condition: no ConfigMap, Deployment, Service exist
+  # Pre-Condition: No configmaps with name=test-the-map, no Deployment, Service exist
-  kube::test::get_object_assert configmaps "{{range.items}}{{$id_field}}:{{end}}" ''
+  kube::test::get_object_assert 'configmaps --field-selector=metadata.name=test-the-map' "{{range.items}}{{${id_field:?}}}:{{end}}" ''
   kube::test::get_object_assert deployment "{{range.items}}{{$id_field}}:{{end}}" ''
   kube::test::get_object_assert services "{{range.items}}{{$id_field}}:{{end}}" ''
   # Command

test/cmd/delete.sh

@@ -37,17 +37,17 @@ run_kubectl_delete_allnamespaces_tests() {
   kubectl delete configmap --dry-run=client -l deletetest=true --all-namespaces
   kubectl delete configmap --dry-run=server -l deletetest=true --all-namespaces
   kubectl config set-context "${CONTEXT}" --namespace="${ns_one}"
-  kube::test::get_object_assert configmap "{{range.items}}{{${id_field:?}}}:{{end}}" 'one:'
+  kube::test::get_object_assert 'configmap -l deletetest' "{{range.items}}{{${id_field:?}}}:{{end}}" 'one:'
   kubectl config set-context "${CONTEXT}" --namespace="${ns_two}"
-  kube::test::get_object_assert configmap "{{range.items}}{{${id_field:?}}}:{{end}}" 'two:'
+  kube::test::get_object_assert 'configmap -l deletetest' "{{range.items}}{{${id_field:?}}}:{{end}}" 'two:'
 
   kubectl delete configmap -l deletetest=true --all-namespaces
 
-  # no configmaps should be in either of those namespaces
+  # no configmaps should be in either of those namespaces with label deletetest
   kubectl config set-context "${CONTEXT}" --namespace="${ns_one}"
-  kube::test::get_object_assert configmap "{{range.items}}{{${id_field:?}}}:{{end}}" ''
+  kube::test::get_object_assert 'configmap -l deletetest' "{{range.items}}{{${id_field:?}}}:{{end}}" ''
   kubectl config set-context "${CONTEXT}" --namespace="${ns_two}"
-  kube::test::get_object_assert configmap "{{range.items}}{{${id_field:?}}}:{{end}}" ''
+  kube::test::get_object_assert 'configmap -l deletetest' "{{range.items}}{{${id_field:?}}}:{{end}}" ''
 
   set +o nounset
   set +o errexit

test/cmd/get.sh

@@ -206,8 +206,8 @@ run_kubectl_get_tests() {
   kubectl delete pods redis-master valid-pod "${kube_flags[@]}"
 
   ### Test 'kubectl get -k <dir>' prints all the items built from a kustomization directory
-  # Pre-condition: no ConfigMap, Deployment, Service exist
+  # Pre-Condition: No configmaps with name=test-the-map, no Deployment, Service exist
-  kube::test::get_object_assert configmaps "{{range.items}}{{$id_field}}:{{end}}" ''
+  kube::test::get_object_assert 'configmaps --field-selector=metadata.name=test-the-map' "{{range.items}}{{${id_field:?}}}:{{end}}" ''
   kube::test::get_object_assert deployment "{{range.items}}{{$id_field}}:{{end}}" ''
   kube::test::get_object_assert services "{{range.items}}{{$id_field}}:{{end}}" ''
   # Command
@@ -224,7 +224,7 @@ run_kubectl_get_tests() {
   kubectl delete -k hack/testdata/kustomize
 
   # Check that all items in the list are deleted
-  kube::test::get_object_assert configmaps "{{range.items}}{{$id_field}}:{{end}}" ''
+  kube::test::get_object_assert 'configmaps --field-selector=metadata.name=test-the-map' "{{range.items}}{{${id_field:?}}}:{{end}}" ''
   kube::test::get_object_assert deployment "{{range.items}}{{$id_field}}:{{end}}" ''
   kube::test::get_object_assert services "{{range.items}}{{$id_field}}:{{end}}" ''
 

test/e2e/auth/service_accounts.go

@@ -582,20 +582,6 @@ var _ = SIGDescribe("ServiceAccounts", func() {
 	})
 
 	ginkgo.It("should support InClusterConfig with token rotation [Slow]", func() {
-		cfg, err := framework.LoadConfig()
-		framework.ExpectNoError(err)
-
-		if _, err := f.ClientSet.CoreV1().ConfigMaps(f.Namespace.Name).Create(context.TODO(), &v1.ConfigMap{
-			ObjectMeta: metav1.ObjectMeta{
-				Name: "kube-root-ca.crt",
-			},
-			Data: map[string]string{
-				"ca.crt": string(cfg.TLSClientConfig.CAData),
-			},
-		}, metav1.CreateOptions{}); err != nil && !apierrors.IsAlreadyExists(err) {
-			framework.Failf("Unexpected err creating kube-ca-crt: %v", err)
-		}
-
 		tenMin := int64(10 * 60)
 		pod := &v1.Pod{
 			ObjectMeta: metav1.ObjectMeta{Name: "inclusterclient"},
@@ -655,7 +641,7 @@ var _ = SIGDescribe("ServiceAccounts", func() {
 				}},
 			},
 		}
-		pod, err = f.ClientSet.CoreV1().Pods(f.Namespace.Name).Create(context.TODO(), pod, metav1.CreateOptions{})
+		pod, err := f.ClientSet.CoreV1().Pods(f.Namespace.Name).Create(context.TODO(), pod, metav1.CreateOptions{})
 		framework.ExpectNoError(err)
 
 		framework.Logf("created pod")
@@ -870,6 +856,69 @@ var _ = SIGDescribe("ServiceAccounts", func() {
 		}
 		framework.ExpectEqual(eventFound, true, "failed to find %v event", watch.Deleted)
 	})
+
+	ginkgo.It("should guarantee kube-root-ca.crt exist in any namespace", func() {
+		const rootCAConfigMapName = "kube-root-ca.crt"
+
+		framework.ExpectNoError(wait.PollImmediate(500*time.Millisecond, wait.ForeverTestTimeout, func() (bool, error) {
+			_, err := f.ClientSet.CoreV1().ConfigMaps(f.Namespace.Name).Get(context.TODO(), rootCAConfigMapName, metav1.GetOptions{})
+			if err == nil {
+				return true, nil
+			}
+			if apierrors.IsNotFound(err) {
+				ginkgo.By("root ca configmap not found, retrying")
+				return false, nil
+			}
+			return false, err
+		}))
+		framework.Logf("Got root ca configmap in namespace %q", f.Namespace.Name)
+
+		framework.ExpectNoError(f.ClientSet.CoreV1().ConfigMaps(f.Namespace.Name).Delete(context.TODO(), rootCAConfigMapName, metav1.DeleteOptions{GracePeriodSeconds: utilptr.Int64Ptr(0)}))
+		framework.Logf("Deleted root ca configmap in namespace %q", f.Namespace.Name)
+
+		framework.ExpectNoError(wait.Poll(500*time.Millisecond, wait.ForeverTestTimeout, func() (bool, error) {
+			ginkgo.By("waiting for a new root ca configmap created")
+			_, err := f.ClientSet.CoreV1().ConfigMaps(f.Namespace.Name).Get(context.TODO(), rootCAConfigMapName, metav1.GetOptions{})
+			if err == nil {
+				return true, nil
+			}
+			if apierrors.IsNotFound(err) {
+				ginkgo.By("root ca configmap not found, retrying")
+				return false, nil
+			}
+			return false, err
+		}))
+		framework.Logf("Recreated root ca configmap in namespace %q", f.Namespace.Name)
+
+		_, err := f.ClientSet.CoreV1().ConfigMaps(f.Namespace.Name).Update(context.TODO(), &v1.ConfigMap{
+			ObjectMeta: metav1.ObjectMeta{
+				Name: rootCAConfigMapName,
+			},
+			Data: map[string]string{
+				"ca.crt": "",
+			},
+		}, metav1.UpdateOptions{})
+		framework.ExpectNoError(err)
+		framework.Logf("Updated root ca configmap in namespace %q", f.Namespace.Name)
+
+		framework.ExpectNoError(wait.Poll(500*time.Millisecond, wait.ForeverTestTimeout, func() (bool, error) {
+			ginkgo.By("waiting for the root ca configmap reconciled")
+			cm, err := f.ClientSet.CoreV1().ConfigMaps(f.Namespace.Name).Get(context.TODO(), rootCAConfigMapName, metav1.GetOptions{})
+			if err != nil {
+				if apierrors.IsNotFound(err) {
+					ginkgo.By("root ca configmap not found, retrying")
+					return false, nil
+				}
+				return false, err
+			}
+			if value, ok := cm.Data["ca.crt"]; !ok || value == "" {
+				ginkgo.By("root ca configmap is not reconciled yet, retrying")
+				return false, nil
+			}
+			return true, nil
+		}))
+		framework.Logf("Reconciled root ca configmap in namespace %q", f.Namespace.Name)
+	})
 })
 
 var reportLogsParser = regexp.MustCompile("([a-zA-Z0-9-_]*)=([a-zA-Z0-9-_]*)$")