kubernetes/pkg/apis/core/validation/conditional_validation.go
Clayton Coleman c6b833ac3c service: fix IPFamily validation and defaulting problems
If the dual-stack flag is enabled and the cluster is single stack IPv6,
the allocator logic for service clusterIP does not properly handle rejecting
a request for an IPv4 family. Return a 422 Invalid on the ipFamily field
when the dual stack flag is on (as it would when it hits beta) and the
cluster is configured for single-stack IPv6.

The family is now defaulted or cleared in BeforeCreate/BeforeUpdate,
and is either inherited from the previous object (if nil or unchanged),
or set to the default strategy's family as necessary. The existing
family defaulting when cluster ip is provided remains in the api
section. We add additonal family defaulting at the time we allocate
the IP to ensure that IPFamily is a consequence of the ClusterIP
and prevent accidental reversion. This defaulting also ensures that
old clients that submit a nil IPFamily for non ClusterIP services
receive a default.

To properly handle validation, make the strategy and the validation code
path condition on which configuration options are passed to service
storage. Move validation and preparation logic inside the strategy where
it belongs. Service validation is now dependent on the configuration of
the server, and as such ValidateConditionService needs to know what the
allowed families are.
2020-05-23 11:08:19 -04:00

229 lines
8.3 KiB
Go

/*
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"
"net"
"strings"
"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"
netutils "k8s.io/utils/net"
)
// ValidateConditionalService validates conditionally valid fields. allowedIPFamilies is an ordered
// list of the valid IP families (IPv4 or IPv6) that are supported. The first family in the slice
// is the cluster default, although the clusterIP here dictates the family defaulting.
func ValidateConditionalService(service, oldService *api.Service, allowedIPFamilies []api.IPFamily) 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)}))
}
}
errs = append(errs, validateIPFamily(service, oldService, allowedIPFamilies)...)
return errs
}
// validateIPFamily checks the IPFamily field.
func validateIPFamily(service, oldService *api.Service, allowedIPFamilies []api.IPFamily) field.ErrorList {
var errs field.ErrorList
// specifically allow an invalid value to remain in storage as long as the user isn't changing it, regardless of gate
if oldService != nil && oldService.Spec.IPFamily != nil && service.Spec.IPFamily != nil && *oldService.Spec.IPFamily == *service.Spec.IPFamily {
return errs
}
// If the gate is off, setting or changing IPFamily is not allowed, but clearing it is
if !utilfeature.DefaultFeatureGate.Enabled(features.IPv6DualStack) {
if service.Spec.IPFamily != nil {
if oldService != nil {
errs = append(errs, ValidateImmutableField(service.Spec.IPFamily, oldService.Spec.IPFamily, field.NewPath("spec", "ipFamily"))...)
} else {
errs = append(errs, field.Forbidden(field.NewPath("spec", "ipFamily"), "programmer error, must be cleared when the dual-stack feature gate is off"))
}
}
return errs
}
// PrepareCreate, PrepareUpdate, and test cases must all set IPFamily when the gate is on
if service.Spec.IPFamily == nil {
errs = append(errs, field.Required(field.NewPath("spec", "ipFamily"), "programmer error, must be set or defaulted by other fields"))
return errs
}
// A user is not allowed to change the IPFamily field, except for ExternalName services
if oldService != nil && oldService.Spec.IPFamily != nil && service.Spec.Type != api.ServiceTypeExternalName {
errs = append(errs, ValidateImmutableField(service.Spec.IPFamily, oldService.Spec.IPFamily, field.NewPath("spec", "ipFamily"))...)
}
// Verify the IPFamily is one of the allowed families
desiredFamily := *service.Spec.IPFamily
if hasIPFamily(allowedIPFamilies, desiredFamily) {
// the IP family is one of the allowed families, verify that it matches cluster IP
switch ip := net.ParseIP(service.Spec.ClusterIP); {
case ip == nil:
// do not need to check anything
case netutils.IsIPv6(ip) && desiredFamily != api.IPv6Protocol:
errs = append(errs, field.Invalid(field.NewPath("spec", "ipFamily"), *service.Spec.IPFamily, "does not match IPv6 cluster IP"))
case !netutils.IsIPv6(ip) && desiredFamily != api.IPv4Protocol:
errs = append(errs, field.Invalid(field.NewPath("spec", "ipFamily"), *service.Spec.IPFamily, "does not match IPv4 cluster IP"))
}
} else {
errs = append(errs, field.Invalid(field.NewPath("spec", "ipFamily"), desiredFamily, fmt.Sprintf("only the following families are allowed: %s", joinIPFamilies(allowedIPFamilies, ", "))))
}
return errs
}
func hasIPFamily(families []api.IPFamily, family api.IPFamily) bool {
for _, allow := range families {
if allow == family {
return true
}
}
return false
}
func joinIPFamilies(families []api.IPFamily, separator string) string {
var b strings.Builder
for i, family := range families {
if i != 0 {
b.WriteString(separator)
}
b.WriteString(string(family))
}
return b.String()
}
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
}