mirror of
https://github.com/k3s-io/kubernetes.git
synced 2025-07-22 19:31:44 +00:00
119 lines
3.6 KiB
Go
119 lines
3.6 KiB
Go
/*
|
|
Copyright 2022 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 ctbattest
|
|
|
|
import (
|
|
"context"
|
|
"fmt"
|
|
"io"
|
|
|
|
"k8s.io/apiserver/pkg/admission"
|
|
genericadmissioninit "k8s.io/apiserver/pkg/admission/initializer"
|
|
"k8s.io/apiserver/pkg/authorization/authorizer"
|
|
"k8s.io/component-base/featuregate"
|
|
"k8s.io/klog/v2"
|
|
api "k8s.io/kubernetes/pkg/apis/certificates"
|
|
"k8s.io/kubernetes/pkg/features"
|
|
"k8s.io/kubernetes/plugin/pkg/admission/certificates"
|
|
)
|
|
|
|
const PluginName = "ClusterTrustBundleAttest"
|
|
|
|
func Register(plugins *admission.Plugins) {
|
|
plugins.Register(PluginName, func(config io.Reader) (admission.Interface, error) {
|
|
return NewPlugin(), nil
|
|
})
|
|
}
|
|
|
|
// Plugin is the ClusterTrustBundle attest plugin.
|
|
//
|
|
// In order to create or update a ClusterTrustBundle that sets signerName,
|
|
// you must have the following permission: group=certificates.k8s.io
|
|
// resource=signers resourceName=<the signer name> verb=attest.
|
|
type Plugin struct {
|
|
*admission.Handler
|
|
authz authorizer.Authorizer
|
|
|
|
inspectedFeatureGates bool
|
|
enabled bool
|
|
}
|
|
|
|
var _ admission.ValidationInterface = &Plugin{}
|
|
var _ admission.InitializationValidator = &Plugin{}
|
|
var _ genericadmissioninit.WantsAuthorizer = &Plugin{}
|
|
var _ genericadmissioninit.WantsFeatures = &Plugin{}
|
|
|
|
func NewPlugin() *Plugin {
|
|
return &Plugin{
|
|
Handler: admission.NewHandler(admission.Create, admission.Update),
|
|
}
|
|
}
|
|
|
|
// SetAuthorizer sets the plugin's authorizer.
|
|
func (p *Plugin) SetAuthorizer(authz authorizer.Authorizer) {
|
|
p.authz = authz
|
|
}
|
|
|
|
// InspectFeatureGates implements WantsFeatures.
|
|
func (p *Plugin) InspectFeatureGates(featureGates featuregate.FeatureGate) {
|
|
p.enabled = featureGates.Enabled(features.ClusterTrustBundle)
|
|
p.inspectedFeatureGates = true
|
|
}
|
|
|
|
// ValidateInitialization checks that the plugin was initialized correctly.
|
|
func (p *Plugin) ValidateInitialization() error {
|
|
if p.authz == nil {
|
|
return fmt.Errorf("%s requires an authorizer", PluginName)
|
|
}
|
|
if !p.inspectedFeatureGates {
|
|
return fmt.Errorf("%s did not see feature gates", PluginName)
|
|
}
|
|
return nil
|
|
}
|
|
|
|
var clusterTrustBundleGroupResource = api.Resource("clustertrustbundles")
|
|
|
|
func (p *Plugin) Validate(ctx context.Context, a admission.Attributes, _ admission.ObjectInterfaces) error {
|
|
if !p.enabled {
|
|
return nil
|
|
}
|
|
if a.GetResource().GroupResource() != clusterTrustBundleGroupResource {
|
|
return nil
|
|
}
|
|
|
|
newBundle, ok := a.GetObject().(*api.ClusterTrustBundle)
|
|
if !ok {
|
|
return admission.NewForbidden(a, fmt.Errorf("expected type ClusterTrustBundle, got: %T", a.GetOldObject()))
|
|
}
|
|
|
|
// Unlike CSRs, it's OK to validate against the *new* object, because
|
|
// updates to signer name will be rejected during validation.
|
|
|
|
// If signer name isn't specified, we don't need to perform the
|
|
// attest check.
|
|
if newBundle.Spec.SignerName == "" {
|
|
return nil
|
|
}
|
|
|
|
if !certificates.IsAuthorizedForSignerName(ctx, p.authz, a.GetUserInfo(), "attest", newBundle.Spec.SignerName) {
|
|
klog.V(4).Infof("user not permitted to attest ClusterTrustBundle %q with signerName %q", newBundle.Name, newBundle.Spec.SignerName)
|
|
return admission.NewForbidden(a, fmt.Errorf("user not permitted to attest for signerName %q", newBundle.Spec.SignerName))
|
|
}
|
|
|
|
return nil
|
|
}
|