ingress-nginx-helm/images/kube-webhook-certgen/rootfs/pkg/k8s/k8s.go
cui fliter 82e836fbe8
fix some comments (#9688)
Signed-off-by: cui fliter <imcusg@gmail.com>
2023-03-05 11:00:57 -08:00

259 lines
7.5 KiB
Go

package k8s
import (
"context"
"fmt"
log "github.com/sirupsen/logrus"
admissionv1 "k8s.io/api/admissionregistration/v1"
v1 "k8s.io/api/core/v1"
k8serrors "k8s.io/apimachinery/pkg/api/errors"
metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
"k8s.io/client-go/kubernetes"
"k8s.io/kube-aggregator/pkg/client/clientset_generated/clientset"
)
type k8s struct {
clientset kubernetes.Interface
aggregatorClientset clientset.Interface
}
func New(clientset kubernetes.Interface, aggregatorClientset clientset.Interface) *k8s {
if clientset == nil {
log.Fatal("no kubernetes client given")
}
if aggregatorClientset == nil {
log.Fatal("no kubernetes aggregator client given")
}
return &k8s{
clientset: clientset,
aggregatorClientset: aggregatorClientset,
}
}
type PatchOptions struct {
ValidatingWebhookConfigurationName string
MutatingWebhookConfigurationName string
APIServiceName string
CABundle []byte
FailurePolicyType admissionv1.FailurePolicyType
}
func (k8s *k8s) PatchObjects(ctx context.Context, options PatchOptions) error {
patchMutating := options.MutatingWebhookConfigurationName != ""
patchValidating := options.ValidatingWebhookConfigurationName != ""
patchAPIService := options.APIServiceName != ""
if !patchMutating && !patchValidating && options.FailurePolicyType != "" {
return fmt.Errorf("failurePolicy specified, but no webhook will be patched")
}
if patchMutating && patchValidating &&
options.MutatingWebhookConfigurationName != options.ValidatingWebhookConfigurationName {
return fmt.Errorf("webhook names must be the same")
}
if patchAPIService {
log.Infof("patching APIService %q", options.APIServiceName)
if err := k8s.patchAPIService(ctx, options.APIServiceName, options.CABundle); err != nil {
// Intentionally don't wrap error here to preserve old behavior and be able to log both
// original error and a message.
return err
}
}
webhookName := options.ValidatingWebhookConfigurationName
if webhookName == "" {
webhookName = options.MutatingWebhookConfigurationName
}
if patchMutating || patchValidating {
return k8s.patchWebhookConfigurations(ctx, webhookName, options.CABundle, options.FailurePolicyType, patchMutating, patchValidating)
}
return nil
}
func (k8s *k8s) patchAPIService(ctx context.Context, objectName string, ca []byte) error {
log.Infof("patching APIService %q", objectName)
c := k8s.aggregatorClientset.ApiregistrationV1().APIServices()
apiService, err := c.Get(ctx, objectName, metav1.GetOptions{})
if err != nil {
return &wrappedError{
err: err,
message: fmt.Sprintf("failed getting APIService %q", objectName),
}
}
apiService.Spec.CABundle = ca
apiService.Spec.InsecureSkipTLSVerify = false
if _, err := c.Update(ctx, apiService, metav1.UpdateOptions{}); err != nil {
return &wrappedError{
err: err,
message: fmt.Sprintf("failed patching APIService %q", objectName),
}
}
log.Debug("patched APIService")
return nil
}
// patchWebhookConfigurations will patch validatingWebhook and mutatingWebhook clientConfig configurations with
// the provided ca data. If failurePolicy is provided, patch all webhooks with this value
func (k8s *k8s) patchWebhookConfigurations(
ctx context.Context,
configurationName string,
ca []byte,
failurePolicy admissionv1.FailurePolicyType,
patchMutating bool,
patchValidating bool,
) error {
log.Infof("patching webhook configurations '%s' mutating=%t, validating=%t, failurePolicy=%s", configurationName, patchMutating, patchValidating, failurePolicy)
if patchValidating {
if err := k8s.patchValidating(ctx, configurationName, ca, failurePolicy); err != nil {
// Intentionally don't wrap error here to preserve old behavior and be able to log both original error and a message.
return err
}
} else {
log.Debug("validating hook patching not required")
}
if patchMutating {
if err := k8s.patchMutating(ctx, configurationName, ca, failurePolicy); err != nil {
// Intentionally don't wrap error here to preserve old behavior and be able to log both original error and a message.
return err
}
} else {
log.Debug("mutating hook patching not required")
}
log.Info("Patched hook(s)")
return nil
}
type wrappedError struct {
err error
message string
}
func (err wrappedError) Error() string {
return err.message
}
func (err wrappedError) Unwrap() error {
return err.err
}
func (k8s *k8s) patchValidating(ctx context.Context, configurationName string, ca []byte, failurePolicy admissionv1.FailurePolicyType) error {
valHook, err := k8s.clientset.
AdmissionregistrationV1().
ValidatingWebhookConfigurations().
Get(ctx, configurationName, metav1.GetOptions{})
if err != nil {
return &wrappedError{
err: err,
message: "failed getting validating webhook",
}
}
for i := range valHook.Webhooks {
h := &valHook.Webhooks[i]
h.ClientConfig.CABundle = ca
if failurePolicy != "" {
h.FailurePolicy = &failurePolicy
}
}
if _, err = k8s.clientset.AdmissionregistrationV1().
ValidatingWebhookConfigurations().
Update(ctx, valHook, metav1.UpdateOptions{}); err != nil {
return &wrappedError{
err: err,
message: "failed patching validating webhook",
}
}
log.Debug("patched validating hook")
return nil
}
func (k8s *k8s) patchMutating(ctx context.Context, configurationName string, ca []byte, failurePolicy admissionv1.FailurePolicyType) error {
mutHook, err := k8s.clientset.
AdmissionregistrationV1().
MutatingWebhookConfigurations().
Get(ctx, configurationName, metav1.GetOptions{})
if err != nil {
return &wrappedError{
err: err,
message: "failed getting mutating webhook",
}
}
for i := range mutHook.Webhooks {
h := &mutHook.Webhooks[i]
h.ClientConfig.CABundle = ca
if failurePolicy != "" {
h.FailurePolicy = &failurePolicy
}
}
if _, err = k8s.clientset.AdmissionregistrationV1().
MutatingWebhookConfigurations().
Update(ctx, mutHook, metav1.UpdateOptions{}); err != nil {
return &wrappedError{
err: err,
message: "failed patching mutating webhook",
}
}
log.Debug("patched mutating hook")
return nil
}
// GetCaFromSecret will check for the presence of a secret. If it exists, will return the content of the
// "ca" from the secret, otherwise will return nil
func (k8s *k8s) GetCaFromSecret(ctx context.Context, secretName string, namespace string) []byte {
log.Debugf("getting secret '%s' in namespace '%s'", secretName, namespace)
secret, err := k8s.clientset.CoreV1().Secrets(namespace).Get(ctx, secretName, metav1.GetOptions{})
if err != nil {
if k8serrors.IsNotFound(err) {
log.WithField("err", err).Info("no secret found")
return nil
}
log.WithField("err", err).Fatal("error getting secret")
}
data := secret.Data["ca"]
if data == nil {
log.Fatal("got secret, but it did not contain a 'ca' key")
}
log.Debug("got secret")
return data
}
// SaveCertsToSecret saves the provided ca, cert and key into a secret in the specified namespace.
func (k8s *k8s) SaveCertsToSecret(ctx context.Context, secretName, namespace, certName, keyName string, ca, cert, key []byte) {
log.Debugf("saving to secret '%s' in namespace '%s'", secretName, namespace)
secret := &v1.Secret{
ObjectMeta: metav1.ObjectMeta{
Name: secretName,
},
Data: map[string][]byte{"ca": ca, certName: cert, keyName: key},
}
log.Debug("saving secret")
_, err := k8s.clientset.CoreV1().Secrets(namespace).Create(ctx, secret, metav1.CreateOptions{})
if err != nil {
log.WithField("err", err).Fatal("failed creating secret")
}
log.Debug("saved secret")
}