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rotator.go
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rotator.go
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package rotator
import (
"bytes"
"context"
"crypto/rand"
"crypto/rsa"
"crypto/tls"
"crypto/x509"
"crypto/x509/pkix"
"encoding/base64"
"encoding/pem"
"fmt"
"math/big"
"os"
"time"
"github.com/pkg/errors"
"go.uber.org/atomic"
corev1 "k8s.io/api/core/v1"
k8sErrors "k8s.io/apimachinery/pkg/api/errors"
"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
"k8s.io/apimachinery/pkg/runtime"
"k8s.io/apimachinery/pkg/runtime/schema"
"k8s.io/apimachinery/pkg/types"
"k8s.io/apimachinery/pkg/util/wait"
"sigs.k8s.io/controller-runtime/pkg/cache"
"sigs.k8s.io/controller-runtime/pkg/client"
"sigs.k8s.io/controller-runtime/pkg/controller"
"sigs.k8s.io/controller-runtime/pkg/handler"
logf "sigs.k8s.io/controller-runtime/pkg/log"
"sigs.k8s.io/controller-runtime/pkg/manager"
"sigs.k8s.io/controller-runtime/pkg/reconcile"
"sigs.k8s.io/controller-runtime/pkg/source"
)
const (
certName = "tls.crt"
keyName = "tls.key"
caCertName = "ca.crt"
caKeyName = "ca.key"
rotationCheckFrequency = 12 * time.Hour
certValidityDuration = 10 * 365 * 24 * time.Hour
lookaheadInterval = 90 * 24 * time.Hour
)
var crLog = logf.Log.WithName("cert-rotation")
// WebhookType it the type of webhook, either validating/mutating webhook, a CRD conversion webhook, or an extension API server
type WebhookType int
const (
//ValidatingWebhook indicates the webhook is a ValidatingWebhook
Validating WebhookType = iota
//MutingWebhook indicates the webhook is a MutatingWebhook
Mutating
//CRDConversionWebhook indicates the webhook is a conversion webhook
CRDConversion
//APIServiceWebhook indicates the webhook is an extension API server
APIService
)
var _ manager.Runnable = &CertRotator{}
var _ manager.LeaderElectionRunnable = &CertRotator{}
var _ manager.Runnable = controllerWrapper{}
var _ manager.LeaderElectionRunnable = controllerWrapper{}
type controllerWrapper struct {
controller.Controller
needLeaderElection bool
}
func (cw controllerWrapper) NeedLeaderElection() bool {
return cw.needLeaderElection
}
// WebhookInfo is used by the rotator to receive info about resources to be updated with certificates
type WebhookInfo struct {
//Name is the name of the webhook for a validating or mutating webhook, or the CRD name in case of a CRD conversion webhook
Name string
Type WebhookType
}
func (w WebhookInfo) gvk() schema.GroupVersionKind {
t2g := map[WebhookType]schema.GroupVersionKind{
Validating: {Group: "admissionregistration.k8s.io", Version: "v1", Kind: "ValidatingWebhookConfiguration"},
Mutating: {Group: "admissionregistration.k8s.io", Version: "v1", Kind: "MutatingWebhookConfiguration"},
CRDConversion: {Group: "apiextensions.k8s.io", Version: "v1", Kind: "CustomResourceDefinition"},
APIService: {Group: "apiregistration.k8s.io", Version: "v1", Kind: "APIService"},
}
return t2g[w.Type]
}
// AddRotator adds the CertRotator and ReconcileWH to the manager.
func AddRotator(mgr manager.Manager, cr *CertRotator) error {
if mgr == nil || cr == nil {
return fmt.Errorf("nil arguments")
}
ns := cr.SecretKey.Namespace
if ns == "" {
return fmt.Errorf("invalid namespace for secret")
}
cache, err := addNamespacedCache(mgr, ns)
if err != nil {
return fmt.Errorf("creating namespaced cache: %w", err)
}
cr.reader = cache
cr.writer = mgr.GetClient() // TODO make overrideable
cr.certsMounted = make(chan struct{})
cr.certsNotMounted = make(chan struct{})
cr.wasCAInjected = atomic.NewBool(false)
cr.caNotInjected = make(chan struct{})
if err := mgr.Add(cr); err != nil {
return err
}
reconciler := &ReconcileWH{
cache: cache,
writer: mgr.GetClient(), // TODO
scheme: mgr.GetScheme(),
ctx: context.Background(),
secretKey: cr.SecretKey,
wasCAInjected: cr.wasCAInjected,
webhooks: cr.Webhooks,
needLeaderElection: cr.RequireLeaderElection,
}
if err := addController(mgr, reconciler); err != nil {
return err
}
return nil
}
// addNamespacedCache will add a new namespace-scoped cache.Cache to the provided manager.
// Informers in the new cache will be scoped to the provided namespace for namespaced resources,
// but will still have cluster-wide visibility into cluster-scoped resources.
// The cache will be started by the manager when it starts, and consumers should synchronize on
// it using WaitForCacheSync().
func addNamespacedCache(mgr manager.Manager, namespace string) (cache.Cache, error) {
c, err := cache.New(mgr.GetConfig(),
cache.Options{
Scheme: mgr.GetScheme(),
Mapper: mgr.GetRESTMapper(),
Namespace: namespace,
})
if err != nil {
return nil, err
}
if err := mgr.Add(c); err != nil {
return nil, fmt.Errorf("registering namespaced cache: %w", err)
}
return c, nil
}
// SyncingSource is a reader that needs syncing prior to being usable.
type SyncingReader interface {
client.Reader
WaitForCacheSync(ctx context.Context) bool
}
// CertRotator contains cert artifacts and a channel to close when the certs are ready.
type CertRotator struct {
reader SyncingReader
writer client.Writer
SecretKey types.NamespacedName
CertDir string
CAName string
CAOrganization string
DNSName string
ExtraDNSNames []string
IsReady chan struct{}
Webhooks []WebhookInfo
RestartOnSecretRefresh bool
ExtKeyUsages *[]x509.ExtKeyUsage
// RequireLeaderElection should be set to true if the CertRotator needs to
// be run in the leader election mode.
RequireLeaderElection bool
certsMounted chan struct{}
certsNotMounted chan struct{}
wasCAInjected *atomic.Bool
caNotInjected chan struct{}
}
func (cr *CertRotator) NeedLeaderElection() bool {
return cr.RequireLeaderElection
}
// Start starts the CertRotator runnable to rotate certs and ensure the certs are ready.
func (cr *CertRotator) Start(ctx context.Context) error {
if cr.reader == nil {
return errors.New("nil reader")
}
if !cr.reader.WaitForCacheSync(ctx) {
return errors.New("failed waiting for reader to sync")
}
if cr.ExtKeyUsages == nil {
cr.ExtKeyUsages = &[]x509.ExtKeyUsage{x509.ExtKeyUsageServerAuth}
}
// explicitly rotate on the first round so that the certificate
// can be bootstrapped, otherwise manager exits before a cert can be written
crLog.Info("starting cert rotator controller")
defer crLog.Info("stopping cert rotator controller")
if err := cr.refreshCertIfNeeded(); err != nil {
crLog.Error(err, "could not refresh cert on startup")
return err
}
// Once the certs are ready, close the channel.
go cr.ensureCertsMounted()
go cr.ensureReady()
ticker := time.NewTicker(rotationCheckFrequency)
tickerLoop:
for {
select {
case <-ticker.C:
if err := cr.refreshCertIfNeeded(); err != nil {
crLog.Error(err, "error rotating certs")
}
case <-ctx.Done():
break tickerLoop
case <-cr.certsNotMounted:
return errors.New("could not mount certs")
case <-cr.caNotInjected:
return errors.New("could not inject certs to webhooks")
}
}
ticker.Stop()
return nil
}
// refreshCertIfNeeded returns whether there's any error when refreshing the certs if needed.
func (cr *CertRotator) refreshCertIfNeeded() error {
refreshFn := func() (bool, error) {
secret := &corev1.Secret{}
if err := cr.reader.Get(context.Background(), cr.SecretKey, secret); err != nil {
return false, errors.Wrap(err, "acquiring secret to update certificates")
}
if secret.Data == nil || !cr.validCACert(secret.Data[caCertName], secret.Data[caKeyName]) {
crLog.Info("refreshing CA and server certs")
if err := cr.refreshCerts(true, secret); err != nil {
crLog.Error(err, "could not refresh CA and server certs")
return false, nil
}
crLog.Info("server certs refreshed")
if cr.RestartOnSecretRefresh {
crLog.Info("Secrets have been updated; exiting so pod can be restarted (This behaviour can be changed with the option RestartOnSecretRefresh)")
os.Exit(0)
}
return true, nil
}
// make sure our reconciler is initialized on startup (either this or the above refreshCerts() will call this)
if !cr.validServerCert(secret.Data[caCertName], secret.Data[certName], secret.Data[keyName]) {
crLog.Info("refreshing server certs")
if err := cr.refreshCerts(false, secret); err != nil {
crLog.Error(err, "could not refresh server certs")
return false, nil
}
crLog.Info("server certs refreshed")
if cr.RestartOnSecretRefresh {
crLog.Info("Secrets have been updated; exiting so pod can be restarted (This behaviour can be changed with the option RestartOnSecretRefresh)")
os.Exit(0)
}
return true, nil
}
crLog.Info("no cert refresh needed")
return true, nil
}
if err := wait.ExponentialBackoff(wait.Backoff{
Duration: 10 * time.Millisecond,
Factor: 2,
Jitter: 1,
Steps: 10,
}, refreshFn); err != nil {
return err
}
return nil
}
func (cr *CertRotator) refreshCerts(refreshCA bool, secret *corev1.Secret) error {
var caArtifacts *KeyPairArtifacts
now := time.Now()
begin := now.Add(-1 * time.Hour)
end := now.Add(certValidityDuration)
if refreshCA {
var err error
caArtifacts, err = cr.CreateCACert(begin, end)
if err != nil {
return err
}
} else {
var err error
caArtifacts, err = buildArtifactsFromSecret(secret)
if err != nil {
return err
}
}
cert, key, err := cr.CreateCertPEM(caArtifacts, begin, end)
if err != nil {
return err
}
if err := cr.writeSecret(cert, key, caArtifacts, secret); err != nil {
return err
}
return nil
}
func injectCert(updatedResource *unstructured.Unstructured, certPem []byte, webhookType WebhookType) error {
switch webhookType {
case Validating:
return injectCertToWebhook(updatedResource, certPem)
case Mutating:
return injectCertToWebhook(updatedResource, certPem)
case CRDConversion:
return injectCertToConversionWebhook(updatedResource, certPem)
case APIService:
return injectCertToApiService(updatedResource, certPem)
}
return fmt.Errorf("Incorrect webhook type")
}
func injectCertToWebhook(wh *unstructured.Unstructured, certPem []byte) error {
webhooks, found, err := unstructured.NestedSlice(wh.Object, "webhooks")
if err != nil {
return err
}
if !found {
return nil
}
for i, h := range webhooks {
hook, ok := h.(map[string]interface{})
if !ok {
return errors.Errorf("webhook %d is not well-formed", i)
}
if err := unstructured.SetNestedField(hook, base64.StdEncoding.EncodeToString(certPem), "clientConfig", "caBundle"); err != nil {
return err
}
webhooks[i] = hook
}
if err := unstructured.SetNestedSlice(wh.Object, webhooks, "webhooks"); err != nil {
return err
}
return nil
}
func injectCertToConversionWebhook(crd *unstructured.Unstructured, certPem []byte) error {
_, found, err := unstructured.NestedMap(crd.Object, "spec", "conversion", "webhook", "clientConfig")
if err != nil {
return err
}
if !found {
return errors.New("`conversion.webhook.clientConfig` field not found in CustomResourceDefinition")
}
if err := unstructured.SetNestedField(crd.Object, base64.StdEncoding.EncodeToString(certPem), "spec", "conversion", "webhook", "clientConfig", "caBundle"); err != nil {
return err
}
return nil
}
func injectCertToApiService(apiService *unstructured.Unstructured, certPem []byte) error {
_, found, err := unstructured.NestedMap(apiService.Object, "spec")
if err != nil {
return err
}
if !found {
return errors.New("`spec` field not found in APIService")
}
if err := unstructured.SetNestedField(apiService.Object, base64.StdEncoding.EncodeToString(certPem), "spec", "caBundle"); err != nil {
return err
}
return nil
}
func (cr *CertRotator) writeSecret(cert, key []byte, caArtifacts *KeyPairArtifacts, secret *corev1.Secret) error {
populateSecret(cert, key, caArtifacts, secret)
return cr.writer.Update(context.Background(), secret)
}
// KeyPairArtifacts stores cert artifacts.
type KeyPairArtifacts struct {
Cert *x509.Certificate
Key *rsa.PrivateKey
CertPEM []byte
KeyPEM []byte
}
func populateSecret(cert, key []byte, caArtifacts *KeyPairArtifacts, secret *corev1.Secret) {
if secret.Data == nil {
secret.Data = make(map[string][]byte)
}
secret.Data[caCertName] = caArtifacts.CertPEM
secret.Data[caKeyName] = caArtifacts.KeyPEM
secret.Data[certName] = cert
secret.Data[keyName] = key
}
func buildArtifactsFromSecret(secret *corev1.Secret) (*KeyPairArtifacts, error) {
caPem, ok := secret.Data[caCertName]
if !ok {
return nil, errors.New(fmt.Sprintf("Cert secret is not well-formed, missing %s", caCertName))
}
keyPem, ok := secret.Data[caKeyName]
if !ok {
return nil, errors.New(fmt.Sprintf("Cert secret is not well-formed, missing %s", caKeyName))
}
caDer, _ := pem.Decode(caPem)
if caDer == nil {
return nil, errors.New("bad CA cert")
}
caCert, err := x509.ParseCertificate(caDer.Bytes)
if err != nil {
return nil, errors.Wrap(err, "while parsing CA cert")
}
keyDer, _ := pem.Decode(keyPem)
if keyDer == nil {
return nil, errors.New("bad CA cert")
}
key, err := x509.ParsePKCS1PrivateKey(keyDer.Bytes)
if err != nil {
return nil, errors.Wrap(err, "while parsing CA key")
}
return &KeyPairArtifacts{
Cert: caCert,
CertPEM: caPem,
KeyPEM: keyPem,
Key: key,
}, nil
}
// CreateCACert creates the self-signed CA cert and private key that will
// be used to sign the server certificate
func (cr *CertRotator) CreateCACert(begin, end time.Time) (*KeyPairArtifacts, error) {
templ := &x509.Certificate{
SerialNumber: big.NewInt(0),
Subject: pkix.Name{
CommonName: cr.CAName,
Organization: []string{cr.CAOrganization},
},
DNSNames: []string{
cr.CAName,
},
NotBefore: begin,
NotAfter: end,
KeyUsage: x509.KeyUsageDigitalSignature | x509.KeyUsageKeyEncipherment | x509.KeyUsageCertSign,
BasicConstraintsValid: true,
IsCA: true,
}
key, err := rsa.GenerateKey(rand.Reader, 2048)
if err != nil {
return nil, errors.Wrap(err, "generating key")
}
der, err := x509.CreateCertificate(rand.Reader, templ, templ, key.Public(), key)
if err != nil {
return nil, errors.Wrap(err, "creating certificate")
}
certPEM, keyPEM, err := pemEncode(der, key)
if err != nil {
return nil, errors.Wrap(err, "encoding PEM")
}
cert, err := x509.ParseCertificate(der)
if err != nil {
return nil, errors.Wrap(err, "parsing certificate")
}
return &KeyPairArtifacts{Cert: cert, Key: key, CertPEM: certPEM, KeyPEM: keyPEM}, nil
}
// CreateCertPEM takes the results of CreateCACert and uses it to create the
// PEM-encoded public certificate and private key, respectively
func (cr *CertRotator) CreateCertPEM(ca *KeyPairArtifacts, begin, end time.Time) ([]byte, []byte, error) {
dnsNames := []string{cr.DNSName}
dnsNames = append(dnsNames, cr.ExtraDNSNames...)
templ := &x509.Certificate{
SerialNumber: big.NewInt(1),
Subject: pkix.Name{
CommonName: cr.DNSName,
},
DNSNames: dnsNames,
NotBefore: begin,
NotAfter: end,
KeyUsage: x509.KeyUsageDigitalSignature | x509.KeyUsageKeyEncipherment,
ExtKeyUsage: *cr.ExtKeyUsages,
BasicConstraintsValid: true,
}
key, err := rsa.GenerateKey(rand.Reader, 2048)
if err != nil {
return nil, nil, errors.Wrap(err, "generating key")
}
der, err := x509.CreateCertificate(rand.Reader, templ, ca.Cert, key.Public(), ca.Key)
if err != nil {
return nil, nil, errors.Wrap(err, "creating certificate")
}
certPEM, keyPEM, err := pemEncode(der, key)
if err != nil {
return nil, nil, errors.Wrap(err, "encoding PEM")
}
return certPEM, keyPEM, nil
}
// pemEncode takes a certificate and encodes it as PEM
func pemEncode(certificateDER []byte, key *rsa.PrivateKey) ([]byte, []byte, error) {
certBuf := &bytes.Buffer{}
if err := pem.Encode(certBuf, &pem.Block{Type: "CERTIFICATE", Bytes: certificateDER}); err != nil {
return nil, nil, errors.Wrap(err, "encoding cert")
}
keyBuf := &bytes.Buffer{}
if err := pem.Encode(keyBuf, &pem.Block{Type: "RSA PRIVATE KEY", Bytes: x509.MarshalPKCS1PrivateKey(key)}); err != nil {
return nil, nil, errors.Wrap(err, "encoding key")
}
return certBuf.Bytes(), keyBuf.Bytes(), nil
}
func lookaheadTime() time.Time {
return time.Now().Add(lookaheadInterval)
}
func (cr *CertRotator) validServerCert(caCert, cert, key []byte) bool {
valid, err := ValidCert(caCert, cert, key, cr.DNSName, cr.ExtKeyUsages, lookaheadTime())
if err != nil {
return false
}
return valid
}
func (cr *CertRotator) validCACert(cert, key []byte) bool {
valid, err := ValidCert(cert, cert, key, cr.CAName, nil, lookaheadTime())
if err != nil {
return false
}
return valid
}
func ValidCert(caCert, cert, key []byte, dnsName string, keyUsages *[]x509.ExtKeyUsage, at time.Time) (bool, error) {
if len(caCert) == 0 || len(cert) == 0 || len(key) == 0 {
return false, errors.New("empty cert")
}
pool := x509.NewCertPool()
caDer, _ := pem.Decode(caCert)
if caDer == nil {
return false, errors.New("bad CA cert")
}
cac, err := x509.ParseCertificate(caDer.Bytes)
if err != nil {
return false, errors.Wrap(err, "parsing CA cert")
}
pool.AddCert(cac)
_, err = tls.X509KeyPair(cert, key)
if err != nil {
return false, errors.Wrap(err, "building key pair")
}
b, _ := pem.Decode(cert)
if b == nil {
return false, errors.New("bad private key")
}
crt, err := x509.ParseCertificate(b.Bytes)
if err != nil {
return false, errors.Wrap(err, "parsing cert")
}
opt := x509.VerifyOptions{
DNSName: dnsName,
Roots: pool,
CurrentTime: at,
}
if keyUsages != nil {
opt.KeyUsages = *keyUsages
}
_, err = crt.Verify(opt)
if err != nil {
return false, errors.Wrap(err, "verifying cert")
}
return true, nil
}
func reconcileSecretAndWebhookMapFunc(webhook WebhookInfo, r *ReconcileWH) func(object client.Object) []reconcile.Request {
return func(object client.Object) []reconcile.Request {
whKey := types.NamespacedName{Name: webhook.Name}
if object.GetNamespace() != whKey.Namespace {
return nil
}
if object.GetName() != whKey.Name {
return nil
}
return []reconcile.Request{{NamespacedName: r.secretKey}}
}
}
// add adds a new Controller to mgr with r as the reconcile.Reconciler
func addController(mgr manager.Manager, r *ReconcileWH) error {
// Create a new controller
c, err := controller.NewUnmanaged("cert-rotator", mgr, controller.Options{Reconciler: r})
if err != nil {
return err
}
if err := mgr.Add(controllerWrapper{c, r.needLeaderElection}); err != nil {
return err
}
err = c.Watch(
source.NewKindWithCache(&corev1.Secret{}, r.cache),
&handler.EnqueueRequestForObject{},
)
if err != nil {
return fmt.Errorf("watching Secrets: %w", err)
}
for _, webhook := range r.webhooks {
wh := &unstructured.Unstructured{}
wh.SetGroupVersionKind(webhook.gvk())
err = c.Watch(
source.NewKindWithCache(wh, r.cache),
handler.EnqueueRequestsFromMapFunc(reconcileSecretAndWebhookMapFunc(webhook, r)),
)
if err != nil {
return fmt.Errorf("watching webhook %s: %w", webhook.Name, err)
}
}
return nil
}
var _ reconcile.Reconciler = &ReconcileWH{}
// ReconcileWH reconciles a validatingwebhookconfiguration, making sure it
// has the appropriate CA cert
type ReconcileWH struct {
writer client.Writer
cache cache.Cache
scheme *runtime.Scheme
ctx context.Context
secretKey types.NamespacedName
webhooks []WebhookInfo
wasCAInjected *atomic.Bool
needLeaderElection bool
}
// Reconcile reads that state of the cluster for a validatingwebhookconfiguration
// object and makes sure the most recent CA cert is included
func (r *ReconcileWH) Reconcile(ctx context.Context, request reconcile.Request) (reconcile.Result, error) {
if request.NamespacedName != r.secretKey {
return reconcile.Result{}, nil
}
if !r.cache.WaitForCacheSync(ctx) {
return reconcile.Result{}, errors.New("cache not ready")
}
secret := &corev1.Secret{}
if err := r.cache.Get(r.ctx, request.NamespacedName, secret); err != nil {
if k8sErrors.IsNotFound(err) {
// Object not found, return. Created objects are automatically garbage collected.
// For additional cleanup logic use finalizers.
return reconcile.Result{}, nil
}
// Error reading the object - requeue the request.
return reconcile.Result{Requeue: true}, err
}
if secret.GetDeletionTimestamp().IsZero() {
artifacts, err := buildArtifactsFromSecret(secret)
if err != nil {
crLog.Error(err, "secret is not well-formed, cannot update webhook configurations")
return reconcile.Result{}, nil
}
// Ensure certs on webhooks
if err := r.ensureCerts(artifacts.CertPEM); err != nil {
return reconcile.Result{}, err
}
// Set CAInjected if the reconciler has not exited early.
r.wasCAInjected.Store(true)
}
return reconcile.Result{}, nil
}
// ensureCerts returns an arbitrary error if multiple errors are encountered,
// while all the errors are logged.
// This is important to allow the controller to reconcile the secret. If an error
// is returned, request will be requeued, and the controller will attempt to reconcile
// the secret again.
// When an error is encountered for when processing a webhook, the error is logged, but
// following webhooks are also attempted to be updated. If multiple errors occur for different
// webhooks, only the last one will be returned. This is ok, as the returned error is only meant
// to indicate that reconciliation failed. The information about all the errors is passed not
// by the returned error, but rather in the logged errors.
func (r *ReconcileWH) ensureCerts(certPem []byte) error {
var anyError error = nil
for _, webhook := range r.webhooks {
gvk := webhook.gvk()
log := crLog.WithValues("name", webhook.Name, "gvk", gvk)
updatedResource := &unstructured.Unstructured{}
updatedResource.SetGroupVersionKind(gvk)
if err := r.cache.Get(r.ctx, types.NamespacedName{Name: webhook.Name}, updatedResource); err != nil {
if k8sErrors.IsNotFound(err) {
log.Error(err, "Webhook not found. Unable to update certificate.")
continue
}
anyError = err
log.Error(err, "Error getting webhook for certificate update.")
continue
}
if !updatedResource.GetDeletionTimestamp().IsZero() {
log.Info("Webhook is being deleted. Unable to update certificate")
continue
}
log.Info("Ensuring CA cert", "name", webhook.Name, "gvk", gvk)
if err := injectCert(updatedResource, certPem, webhook.Type); err != nil {
log.Error(err, "Unable to inject cert to webhook.")
anyError = err
continue
}
if err := r.writer.Update(r.ctx, updatedResource); err != nil {
log.Error(err, "Error updating webhook with certificate")
anyError = err
continue
}
}
return anyError
}
// ensureCertsMounted ensure the cert files exist.
func (cr *CertRotator) ensureCertsMounted() {
checkFn := func() (bool, error) {
certFile := cr.CertDir + "/" + certName
_, err := os.Stat(certFile)
if err == nil {
return true, nil
}
return false, nil
}
if err := wait.ExponentialBackoff(wait.Backoff{
Duration: 1 * time.Second,
Factor: 2,
Jitter: 1,
Steps: 10,
}, checkFn); err != nil {
crLog.Error(err, "max retries for checking certs existence")
close(cr.certsNotMounted)
return
}
crLog.Info(fmt.Sprintf("certs are ready in %s", cr.CertDir))
close(cr.certsMounted)
}
// ensureReady ensure the cert files exist and the CAs are injected.
func (cr *CertRotator) ensureReady() {
<-cr.certsMounted
checkFn := func() (bool, error) {
return cr.wasCAInjected.Load(), nil
}
if err := wait.ExponentialBackoff(wait.Backoff{
Duration: 1 * time.Second,
Factor: 2,
Jitter: 1,
Steps: 10,
}, checkFn); err != nil {
crLog.Error(err, "max retries for checking CA injection")
close(cr.caNotInjected)
return
}
crLog.Info("CA certs are injected to webhooks")
close(cr.IsReady)
}