Move conditional validation for SCTPSupport to validation functions with knowledge of old objects

pkg/apis/core/validation/BUILD

@@ -7,6 +7,7 @@ load(
 go_library(
     name = "go_default_library",
     srcs = [
+        "conditional_validation.go",
         "doc.go",
         "events.go",
         "validation.go",
@@ -46,6 +47,7 @@ go_library(
 go_test(
     name = "go_default_test",
     srcs = [
+        "conditional_validation_test.go",
         "events_test.go",
         "validation_test.go",
     ],
@@ -59,6 +61,7 @@ go_test(
         "//staging/src/k8s.io/api/core/v1:go_default_library",
         "//staging/src/k8s.io/apimachinery/pkg/api/resource:go_default_library",
         "//staging/src/k8s.io/apimachinery/pkg/apis/meta/v1:go_default_library",
+        "//staging/src/k8s.io/apimachinery/pkg/util/diff:go_default_library",
         "//staging/src/k8s.io/apimachinery/pkg/util/intstr:go_default_library",
         "//staging/src/k8s.io/apimachinery/pkg/util/validation:go_default_library",
         "//staging/src/k8s.io/apimachinery/pkg/util/validation/field:go_default_library",

pkg/apis/core/validation/conditional_validation.go

@@ -0,0 +1,148 @@
+/*
+Copyright 2019 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package validation
+
+import (
+	"k8s.io/apimachinery/pkg/util/validation/field"
+	utilfeature "k8s.io/apiserver/pkg/util/feature"
+	api "k8s.io/kubernetes/pkg/apis/core"
+	"k8s.io/kubernetes/pkg/features"
+)
+
+// ValidateConditionalService validates conditionally valid fields.
+func ValidateConditionalService(service, oldService *api.Service) field.ErrorList {
+	var errs field.ErrorList
+	// If the SCTPSupport feature is disabled, and the old object isn't using the SCTP feature, prevent the new object from using it
+	if !utilfeature.DefaultFeatureGate.Enabled(features.SCTPSupport) && len(serviceSCTPFields(oldService)) == 0 {
+		for _, f := range serviceSCTPFields(service) {
+			errs = append(errs, field.NotSupported(f, api.ProtocolSCTP, []string{string(api.ProtocolTCP), string(api.ProtocolUDP)}))
+		}
+	}
+	return errs
+}
+
+func serviceSCTPFields(service *api.Service) []*field.Path {
+	if service == nil {
+		return nil
+	}
+	fields := []*field.Path{}
+	for pIndex, p := range service.Spec.Ports {
+		if p.Protocol == api.ProtocolSCTP {
+			fields = append(fields, field.NewPath("spec.ports").Index(pIndex).Child("protocol"))
+		}
+	}
+	return fields
+}
+
+// ValidateConditionalEndpoints validates conditionally valid fields.
+func ValidateConditionalEndpoints(endpoints, oldEndpoints *api.Endpoints) field.ErrorList {
+	var errs field.ErrorList
+	// If the SCTPSupport feature is disabled, and the old object isn't using the SCTP feature, prevent the new object from using it
+	if !utilfeature.DefaultFeatureGate.Enabled(features.SCTPSupport) && len(endpointsSCTPFields(oldEndpoints)) == 0 {
+		for _, f := range endpointsSCTPFields(endpoints) {
+			errs = append(errs, field.NotSupported(f, api.ProtocolSCTP, []string{string(api.ProtocolTCP), string(api.ProtocolUDP)}))
+		}
+	}
+	return errs
+}
+
+func endpointsSCTPFields(endpoints *api.Endpoints) []*field.Path {
+	if endpoints == nil {
+		return nil
+	}
+	fields := []*field.Path{}
+	for sIndex, s := range endpoints.Subsets {
+		for pIndex, p := range s.Ports {
+			if p.Protocol == api.ProtocolSCTP {
+				fields = append(fields, field.NewPath("subsets").Index(sIndex).Child("ports").Index(pIndex).Child("protocol"))
+			}
+		}
+	}
+	return fields
+}
+
+// ValidateConditionalPodTemplate validates conditionally valid fields.
+// This should be called from Validate/ValidateUpdate for all resources containing a PodTemplateSpec
+func ValidateConditionalPodTemplate(podTemplate, oldPodTemplate *api.PodTemplateSpec, fldPath *field.Path) field.ErrorList {
+	var (
+		podSpec    *api.PodSpec
+		oldPodSpec *api.PodSpec
+	)
+	if podTemplate != nil {
+		podSpec = &podTemplate.Spec
+	}
+	if oldPodTemplate != nil {
+		oldPodSpec = &oldPodTemplate.Spec
+	}
+	return validateConditionalPodSpec(podSpec, oldPodSpec, fldPath.Child("spec"))
+}
+
+// ValidateConditionalPod validates conditionally valid fields.
+// This should be called from Validate/ValidateUpdate for all resources containing a Pod
+func ValidateConditionalPod(pod, oldPod *api.Pod, fldPath *field.Path) field.ErrorList {
+	var (
+		podSpec    *api.PodSpec
+		oldPodSpec *api.PodSpec
+	)
+	if pod != nil {
+		podSpec = &pod.Spec
+	}
+	if oldPod != nil {
+		oldPodSpec = &oldPod.Spec
+	}
+	return validateConditionalPodSpec(podSpec, oldPodSpec, fldPath.Child("spec"))
+}
+
+func validateConditionalPodSpec(podSpec, oldPodSpec *api.PodSpec, fldPath *field.Path) field.ErrorList {
+	// Always make sure we have a non-nil current pod spec
+	if podSpec == nil {
+		podSpec = &api.PodSpec{}
+	}
+
+	errs := field.ErrorList{}
+
+	// If the SCTPSupport feature is disabled, and the old object isn't using the SCTP feature, prevent the new object from using it
+	if !utilfeature.DefaultFeatureGate.Enabled(features.SCTPSupport) && len(podSCTPFields(oldPodSpec, nil)) == 0 {
+		for _, f := range podSCTPFields(podSpec, fldPath) {
+			errs = append(errs, field.NotSupported(f, api.ProtocolSCTP, []string{string(api.ProtocolTCP), string(api.ProtocolUDP)}))
+		}
+	}
+
+	return errs
+}
+
+func podSCTPFields(podSpec *api.PodSpec, fldPath *field.Path) []*field.Path {
+	if podSpec == nil {
+		return nil
+	}
+	fields := []*field.Path{}
+	for cIndex, c := range podSpec.InitContainers {
+		for pIndex, p := range c.Ports {
+			if p.Protocol == api.ProtocolSCTP {
+				fields = append(fields, fldPath.Child("initContainers").Index(cIndex).Child("ports").Index(pIndex).Child("protocol"))
+			}
+		}
+	}
+	for cIndex, c := range podSpec.Containers {
+		for pIndex, p := range c.Ports {
+			if p.Protocol == api.ProtocolSCTP {
+				fields = append(fields, fldPath.Child("containers").Index(cIndex).Child("ports").Index(pIndex).Child("protocol"))
+			}
+		}
+	}
+	return fields
+}

pkg/apis/core/validation/conditional_validation_test.go

@@ -0,0 +1,253 @@
+/*
+Copyright 2019 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package validation
+
+import (
+	"fmt"
+	"reflect"
+	"testing"
+
+	"k8s.io/apimachinery/pkg/util/diff"
+	utilfeature "k8s.io/apiserver/pkg/util/feature"
+	utilfeaturetesting "k8s.io/apiserver/pkg/util/feature/testing"
+	api "k8s.io/kubernetes/pkg/apis/core"
+	"k8s.io/kubernetes/pkg/features"
+)
+
+func TestValidatePodSCTP(t *testing.T) {
+	objectWithValue := func() *api.Pod {
+		return &api.Pod{
+			Spec: api.PodSpec{
+				Containers:     []api.Container{{Name: "container1", Image: "testimage", Ports: []api.ContainerPort{{ContainerPort: 80, Protocol: api.ProtocolSCTP}}}},
+				InitContainers: []api.Container{{Name: "container2", Image: "testimage", Ports: []api.ContainerPort{{ContainerPort: 90, Protocol: api.ProtocolSCTP}}}},
+			},
+		}
+	}
+	objectWithoutValue := func() *api.Pod {
+		return &api.Pod{
+			Spec: api.PodSpec{
+				Containers:     []api.Container{{Name: "container1", Image: "testimage", Ports: []api.ContainerPort{{ContainerPort: 80, Protocol: api.ProtocolTCP}}}},
+				InitContainers: []api.Container{{Name: "container2", Image: "testimage", Ports: []api.ContainerPort{{ContainerPort: 90, Protocol: api.ProtocolTCP}}}},
+			},
+		}
+	}
+
+	objectInfo := []struct {
+		description string
+		hasValue    bool
+		object      func() *api.Pod
+	}{
+		{
+			description: "has value",
+			hasValue:    true,
+			object:      objectWithValue,
+		},
+		{
+			description: "does not have value",
+			hasValue:    false,
+			object:      objectWithoutValue,
+		},
+		{
+			description: "is nil",
+			hasValue:    false,
+			object:      func() *api.Pod { return nil },
+		},
+	}
+
+	for _, enabled := range []bool{true, false} {
+		for _, oldPodInfo := range objectInfo {
+			for _, newPodInfo := range objectInfo {
+				oldPodHasValue, oldPod := oldPodInfo.hasValue, oldPodInfo.object()
+				newPodHasValue, newPod := newPodInfo.hasValue, newPodInfo.object()
+				if newPod == nil {
+					continue
+				}
+
+				t.Run(fmt.Sprintf("feature enabled=%v, old object %v, new object %v", enabled, oldPodInfo.description, newPodInfo.description), func(t *testing.T) {
+					defer utilfeaturetesting.SetFeatureGateDuringTest(t, utilfeature.DefaultFeatureGate, features.SCTPSupport, enabled)()
+					errs := ValidateConditionalPod(newPod, oldPod, nil)
+					// objects should never be changed
+					if !reflect.DeepEqual(oldPod, oldPodInfo.object()) {
+						t.Errorf("old object changed: %v", diff.ObjectReflectDiff(oldPod, oldPodInfo.object()))
+					}
+					if !reflect.DeepEqual(newPod, newPodInfo.object()) {
+						t.Errorf("new object changed: %v", diff.ObjectReflectDiff(newPod, newPodInfo.object()))
+					}
+
+					switch {
+					case enabled || oldPodHasValue || !newPodHasValue:
+						if len(errs) > 0 {
+							t.Errorf("unexpected errors: %v", errs)
+						}
+					default:
+						if len(errs) != 2 {
+							t.Errorf("expected 2 errors, got %v", errs)
+						}
+					}
+				})
+			}
+		}
+	}
+}
+
+func TestValidateServiceSCTP(t *testing.T) {
+	objectWithValue := func() *api.Service {
+		return &api.Service{
+			Spec: api.ServiceSpec{
+				Ports: []api.ServicePort{{Protocol: api.ProtocolSCTP}},
+			},
+		}
+	}
+	objectWithoutValue := func() *api.Service {
+		return &api.Service{
+			Spec: api.ServiceSpec{
+				Ports: []api.ServicePort{{Protocol: api.ProtocolTCP}},
+			},
+		}
+	}
+
+	objectInfo := []struct {
+		description string
+		hasValue    bool
+		object      func() *api.Service
+	}{
+		{
+			description: "has value",
+			hasValue:    true,
+			object:      objectWithValue,
+		},
+		{
+			description: "does not have value",
+			hasValue:    false,
+			object:      objectWithoutValue,
+		},
+		{
+			description: "is nil",
+			hasValue:    false,
+			object:      func() *api.Service { return nil },
+		},
+	}
+
+	for _, enabled := range []bool{true, false} {
+		for _, oldServiceInfo := range objectInfo {
+			for _, newServiceInfo := range objectInfo {
+				oldServiceHasValue, oldService := oldServiceInfo.hasValue, oldServiceInfo.object()
+				newServiceHasValue, newService := newServiceInfo.hasValue, newServiceInfo.object()
+				if newService == nil {
+					continue
+				}
+
+				t.Run(fmt.Sprintf("feature enabled=%v, old object %v, new object %v", enabled, oldServiceInfo.description, newServiceInfo.description), func(t *testing.T) {
+					defer utilfeaturetesting.SetFeatureGateDuringTest(t, utilfeature.DefaultFeatureGate, features.SCTPSupport, enabled)()
+					errs := ValidateConditionalService(newService, oldService)
+					// objects should never be changed
+					if !reflect.DeepEqual(oldService, oldServiceInfo.object()) {
+						t.Errorf("old object changed: %v", diff.ObjectReflectDiff(oldService, oldServiceInfo.object()))
+					}
+					if !reflect.DeepEqual(newService, newServiceInfo.object()) {
+						t.Errorf("new object changed: %v", diff.ObjectReflectDiff(newService, newServiceInfo.object()))
+					}
+
+					switch {
+					case enabled || oldServiceHasValue || !newServiceHasValue:
+						if len(errs) > 0 {
+							t.Errorf("unexpected errors: %v", errs)
+						}
+					default:
+						if len(errs) != 1 {
+							t.Errorf("expected 1 error, got %v", errs)
+						}
+					}
+				})
+			}
+		}
+	}
+}
+
+func TestValidateEndpointsSCTP(t *testing.T) {
+	objectWithValue := func() *api.Endpoints {
+		return &api.Endpoints{
+			Subsets: []api.EndpointSubset{
+				{Ports: []api.EndpointPort{{Protocol: api.ProtocolSCTP}}},
+			},
+		}
+	}
+	objectWithoutValue := func() *api.Endpoints {
+		return &api.Endpoints{
+			Subsets: []api.EndpointSubset{
+				{Ports: []api.EndpointPort{{Protocol: api.ProtocolTCP}}},
+			},
+		}
+	}
+
+	objectInfo := []struct {
+		description string
+		hasValue    bool
+		object      func() *api.Endpoints
+	}{
+		{
+			description: "has value",
+			hasValue:    true,
+			object:      objectWithValue,
+		},
+		{
+			description: "does not have value",
+			hasValue:    false,
+			object:      objectWithoutValue,
+		},
+		{
+			description: "is nil",
+			hasValue:    false,
+			object:      func() *api.Endpoints { return nil },
+		},
+	}
+
+	for _, enabled := range []bool{true, false} {
+		for _, oldEndpointsInfo := range objectInfo {
+			for _, newEndpointsInfo := range objectInfo {
+				oldEndpointsHasValue, oldEndpoints := oldEndpointsInfo.hasValue, oldEndpointsInfo.object()
+				newEndpointsHasValue, newEndpoints := newEndpointsInfo.hasValue, newEndpointsInfo.object()
+				if newEndpoints == nil {
+					continue
+				}
+
+				t.Run(fmt.Sprintf("feature enabled=%v, old object %v, new object %v", enabled, oldEndpointsInfo.description, newEndpointsInfo.description), func(t *testing.T) {
+					defer utilfeaturetesting.SetFeatureGateDuringTest(t, utilfeature.DefaultFeatureGate, features.SCTPSupport, enabled)()
+					errs := ValidateConditionalEndpoints(newEndpoints, oldEndpoints)
+					// objects should never be changed
+					if !reflect.DeepEqual(oldEndpoints, oldEndpointsInfo.object()) {
+						t.Errorf("old object changed: %v", diff.ObjectReflectDiff(oldEndpoints, oldEndpointsInfo.object()))
+					}
+					if !reflect.DeepEqual(newEndpoints, newEndpointsInfo.object()) {
+						t.Errorf("new object changed: %v", diff.ObjectReflectDiff(newEndpoints, newEndpointsInfo.object()))
+					}
+
+					switch {
+					case enabled || oldEndpointsHasValue || !newEndpointsHasValue:
+						if len(errs) > 0 {
+							t.Errorf("unexpected errors: %v", errs)
+						}
+					default:
+						if len(errs) != 1 {
+							t.Errorf("expected 1 error, got %v", errs)
+						}
+					}
+				})
+			}
+		}
+	}
+}

pkg/apis/core/validation/validation.go

@@ -1969,8 +1969,6 @@ func validateContainerPorts(ports []core.ContainerPort, fldPath *field.Path) fie
 		}
 		if len(port.Protocol) == 0 {
 			allErrs = append(allErrs, field.Required(idxPath.Child("protocol"), ""))
-		} else if !utilfeature.DefaultFeatureGate.Enabled(features.SCTPSupport) && port.Protocol == core.ProtocolSCTP {
-			allErrs = append(allErrs, field.NotSupported(idxPath.Child("protocol"), port.Protocol, []string{string(core.ProtocolTCP), string(core.ProtocolUDP)}))
 		} else if !supportedPortProtocols.Has(string(port.Protocol)) {
 			allErrs = append(allErrs, field.NotSupported(idxPath.Child("protocol"), port.Protocol, supportedPortProtocols.List()))
 		}
@@ -3724,9 +3722,7 @@ func ValidateService(service *core.Service) field.ErrorList {
 		includeProtocols := sets.NewString()
 		for i := range service.Spec.Ports {
 			portPath := portsPath.Index(i)
-			if !utilfeature.DefaultFeatureGate.Enabled(features.SCTPSupport) && service.Spec.Ports[i].Protocol == core.ProtocolSCTP {
-				allErrs = append(allErrs, field.NotSupported(portPath.Child("protocol"), service.Spec.Ports[i].Protocol, []string{string(core.ProtocolTCP), string(core.ProtocolUDP)}))
-			} else if !supportedPortProtocols.Has(string(service.Spec.Ports[i].Protocol)) {
+			if !supportedPortProtocols.Has(string(service.Spec.Ports[i].Protocol)) {
 				allErrs = append(allErrs, field.Invalid(portPath.Child("protocol"), service.Spec.Ports[i].Protocol, "cannot create an external load balancer with non-TCP/UDP/SCTP ports"))
 			} else {
 				includeProtocols.Insert(string(service.Spec.Ports[i].Protocol))
@@ -3825,8 +3821,6 @@ func validateServicePort(sp *core.ServicePort, requireName, isHeadlessService bo
 
 	if len(sp.Protocol) == 0 {
 		allErrs = append(allErrs, field.Required(fldPath.Child("protocol"), ""))
-	} else if !utilfeature.DefaultFeatureGate.Enabled(features.SCTPSupport) && sp.Protocol == core.ProtocolSCTP {
-		allErrs = append(allErrs, field.NotSupported(fldPath.Child("protocol"), sp.Protocol, []string{string(core.ProtocolTCP), string(core.ProtocolUDP)}))
 	} else if !supportedPortProtocols.Has(string(sp.Protocol)) {
 		allErrs = append(allErrs, field.NotSupported(fldPath.Child("protocol"), sp.Protocol, supportedPortProtocols.List()))
 	}
@@ -5133,8 +5127,6 @@ func validateEndpointPort(port *core.EndpointPort, requireName bool, fldPath *fi
 	}
 	if len(port.Protocol) == 0 {
 		allErrs = append(allErrs, field.Required(fldPath.Child("protocol"), ""))
-	} else if !utilfeature.DefaultFeatureGate.Enabled(features.SCTPSupport) && port.Protocol == core.ProtocolSCTP {
-		allErrs = append(allErrs, field.NotSupported(fldPath.Child("protocol"), port.Protocol, []string{string(core.ProtocolTCP), string(core.ProtocolUDP)}))
 	} else if !supportedPortProtocols.Has(string(port.Protocol)) {
 		allErrs = append(allErrs, field.NotSupported(fldPath.Child("protocol"), port.Protocol, supportedPortProtocols.List()))
 	}

pkg/apis/networking/validation/BUILD

@@ -8,13 +8,17 @@ load(
 
 go_test(
     name = "go_default_test",
-    srcs = ["validation_test.go"],
+    srcs = [
+        "conditional_validation_test.go",
+        "validation_test.go",
+    ],
     embed = [":go_default_library"],
     deps = [
         "//pkg/apis/core:go_default_library",
         "//pkg/apis/networking:go_default_library",
         "//pkg/features:go_default_library",
         "//staging/src/k8s.io/apimachinery/pkg/apis/meta/v1:go_default_library",
+        "//staging/src/k8s.io/apimachinery/pkg/util/diff:go_default_library",
         "//staging/src/k8s.io/apimachinery/pkg/util/intstr:go_default_library",
         "//staging/src/k8s.io/apiserver/pkg/util/feature:go_default_library",
         "//staging/src/k8s.io/apiserver/pkg/util/feature/testing:go_default_library",
@@ -23,7 +27,10 @@ go_test(
 
 go_library(
     name = "go_default_library",
-    srcs = ["validation.go"],
+    srcs = [
+        "conditional_validation.go",
+        "validation.go",
+    ],
     importpath = "k8s.io/kubernetes/pkg/apis/networking/validation",
     deps = [
         "//pkg/apis/core:go_default_library",

pkg/apis/networking/validation/conditional_validation.go

@@ -0,0 +1,59 @@
+/*
+Copyright 2019 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package validation
+
+import (
+	"k8s.io/apimachinery/pkg/util/validation/field"
+	utilfeature "k8s.io/apiserver/pkg/util/feature"
+	api "k8s.io/kubernetes/pkg/apis/core"
+	"k8s.io/kubernetes/pkg/apis/networking"
+	"k8s.io/kubernetes/pkg/features"
+)
+
+// ValidateConditionalNetworkPolicy validates conditionally valid fields.
+func ValidateConditionalNetworkPolicy(np, oldNP *networking.NetworkPolicy) field.ErrorList {
+	var errs field.ErrorList
+	// If the SCTPSupport feature is disabled, and the old object isn't using the SCTP feature, prevent the new object from using it
+	if !utilfeature.DefaultFeatureGate.Enabled(features.SCTPSupport) && len(sctpFields(oldNP)) == 0 {
+		for _, f := range sctpFields(np) {
+			errs = append(errs, field.NotSupported(f, api.ProtocolSCTP, []string{string(api.ProtocolTCP), string(api.ProtocolUDP)}))
+		}
+	}
+	return errs
+}
+
+func sctpFields(np *networking.NetworkPolicy) []*field.Path {
+	if np == nil {
+		return nil
+	}
+	fields := []*field.Path{}
+	for iIndex, e := range np.Spec.Ingress {
+		for pIndex, p := range e.Ports {
+			if p.Protocol != nil && *p.Protocol == api.ProtocolSCTP {
+				fields = append(fields, field.NewPath("spec.ingress").Index(iIndex).Child("ports").Index(pIndex).Child("protocol"))
+			}
+		}
+	}
+	for eIndex, e := range np.Spec.Egress {
+		for pIndex, p := range e.Ports {
+			if p.Protocol != nil && *p.Protocol == api.ProtocolSCTP {
+				fields = append(fields, field.NewPath("spec.egress").Index(eIndex).Child("ports").Index(pIndex).Child("protocol"))
+			}
+		}
+	}
+	return fields
+}

pkg/apis/networking/validation/conditional_validation_test.go

@@ -0,0 +1,108 @@
+/*
+Copyright 2019 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package validation
+
+import (
+	"fmt"
+	"reflect"
+	"testing"
+
+	"k8s.io/apimachinery/pkg/util/diff"
+	utilfeature "k8s.io/apiserver/pkg/util/feature"
+	utilfeaturetesting "k8s.io/apiserver/pkg/util/feature/testing"
+	api "k8s.io/kubernetes/pkg/apis/core"
+	"k8s.io/kubernetes/pkg/apis/networking"
+	"k8s.io/kubernetes/pkg/features"
+)
+
+func TestValidateNetworkPolicySCTP(t *testing.T) {
+	sctpProtocol := api.ProtocolSCTP
+	tcpProtocol := api.ProtocolTCP
+	objectWithValue := func() *networking.NetworkPolicy {
+		return &networking.NetworkPolicy{
+			Spec: networking.NetworkPolicySpec{
+				Ingress: []networking.NetworkPolicyIngressRule{{Ports: []networking.NetworkPolicyPort{{Protocol: &sctpProtocol}}}},
+				Egress:  []networking.NetworkPolicyEgressRule{{Ports: []networking.NetworkPolicyPort{{Protocol: &sctpProtocol}}}},
+			},
+		}
+	}
+	objectWithoutValue := func() *networking.NetworkPolicy {
+		return &networking.NetworkPolicy{
+			Spec: networking.NetworkPolicySpec{
+				Ingress: []networking.NetworkPolicyIngressRule{{Ports: []networking.NetworkPolicyPort{{Protocol: &tcpProtocol}}}},
+				Egress:  []networking.NetworkPolicyEgressRule{{Ports: []networking.NetworkPolicyPort{{Protocol: &tcpProtocol}}}},
+			},
+		}
+	}
+
+	objectInfo := []struct {
+		description string
+		hasValue    bool
+		object      func() *networking.NetworkPolicy
+	}{
+		{
+			description: "has value",
+			hasValue:    true,
+			object:      objectWithValue,
+		},
+		{
+			description: "does not have value",
+			hasValue:    false,
+			object:      objectWithoutValue,
+		},
+		{
+			description: "is nil",
+			hasValue:    false,
+			object:      func() *networking.NetworkPolicy { return nil },
+		},
+	}
+
+	for _, enabled := range []bool{true, false} {
+		for _, oldNetworkPolicyInfo := range objectInfo {
+			for _, newNetworkPolicyInfo := range objectInfo {
+				oldNetworkPolicyHasValue, oldNetworkPolicy := oldNetworkPolicyInfo.hasValue, oldNetworkPolicyInfo.object()
+				newNetworkPolicyHasValue, newNetworkPolicy := newNetworkPolicyInfo.hasValue, newNetworkPolicyInfo.object()
+				if newNetworkPolicy == nil {
+					continue
+				}
+
+				t.Run(fmt.Sprintf("feature enabled=%v, old object %v, new object %v", enabled, oldNetworkPolicyInfo.description, newNetworkPolicyInfo.description), func(t *testing.T) {
+					defer utilfeaturetesting.SetFeatureGateDuringTest(t, utilfeature.DefaultFeatureGate, features.SCTPSupport, enabled)()
+					errs := ValidateConditionalNetworkPolicy(newNetworkPolicy, oldNetworkPolicy)
+					// objects should never be changed
+					if !reflect.DeepEqual(oldNetworkPolicy, oldNetworkPolicyInfo.object()) {
+						t.Errorf("old object changed: %v", diff.ObjectReflectDiff(oldNetworkPolicy, oldNetworkPolicyInfo.object()))
+					}
+					if !reflect.DeepEqual(newNetworkPolicy, newNetworkPolicyInfo.object()) {
+						t.Errorf("new object changed: %v", diff.ObjectReflectDiff(newNetworkPolicy, newNetworkPolicyInfo.object()))
+					}
+
+					switch {
+					case enabled || oldNetworkPolicyHasValue || !newNetworkPolicyHasValue:
+						if len(errs) > 0 {
+							t.Errorf("unexpected errors: %v", errs)
+						}
+					default:
+						if len(errs) != 2 {
+							t.Errorf("expected 2 errors, got %v", errs)
+						}
+					}
+				})
+			}
+		}
+	}
+}

pkg/apis/networking/validation/validation.go

@@ -23,11 +23,9 @@ import (
 	"k8s.io/apimachinery/pkg/util/sets"
 	"k8s.io/apimachinery/pkg/util/validation"
 	"k8s.io/apimachinery/pkg/util/validation/field"
-	utilfeature "k8s.io/apiserver/pkg/util/feature"
 	api "k8s.io/kubernetes/pkg/apis/core"
 	apivalidation "k8s.io/kubernetes/pkg/apis/core/validation"
 	"k8s.io/kubernetes/pkg/apis/networking"
-	"k8s.io/kubernetes/pkg/features"
 )
 
 // ValidateNetworkPolicyName can be used to check whether the given networkpolicy
@@ -39,12 +37,8 @@ func ValidateNetworkPolicyName(name string, prefix bool) []string {
 // ValidateNetworkPolicyPort validates a NetworkPolicyPort
 func ValidateNetworkPolicyPort(port *networking.NetworkPolicyPort, portPath *field.Path) field.ErrorList {
 	allErrs := field.ErrorList{}
-	if utilfeature.DefaultFeatureGate.Enabled(features.SCTPSupport) {
-		if port.Protocol != nil && *port.Protocol != api.ProtocolTCP && *port.Protocol != api.ProtocolUDP && *port.Protocol != api.ProtocolSCTP {
-			allErrs = append(allErrs, field.NotSupported(portPath.Child("protocol"), *port.Protocol, []string{string(api.ProtocolTCP), string(api.ProtocolUDP), string(api.ProtocolSCTP)}))
-		}
-	} else if port.Protocol != nil && *port.Protocol != api.ProtocolTCP && *port.Protocol != api.ProtocolUDP {
-		allErrs = append(allErrs, field.NotSupported(portPath.Child("protocol"), *port.Protocol, []string{string(api.ProtocolTCP), string(api.ProtocolUDP)}))
+	if port.Protocol != nil && *port.Protocol != api.ProtocolTCP && *port.Protocol != api.ProtocolUDP && *port.Protocol != api.ProtocolSCTP {
+		allErrs = append(allErrs, field.NotSupported(portPath.Child("protocol"), *port.Protocol, []string{string(api.ProtocolTCP), string(api.ProtocolUDP), string(api.ProtocolSCTP)}))
 	}
 	if port.Port != nil {
 		if port.Port.Type == intstr.Int {