kubernetes/pkg/apis/core/validation/conditional_validation.go
2020-10-15 08:56:33 -04:00

111 lines
4.2 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
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()
}