fix authenticators bug: stop allowing usage when validation fails

This commit is contained in:
Ryan Richard
2024-07-12 15:03:48 -07:00
parent 6b722a14c8
commit b5a509f27f
4 changed files with 312 additions and 35 deletions

View File

@@ -119,6 +119,9 @@ type cachedJWTAuthenticator struct {
}
func (c *cachedJWTAuthenticator) Close() {
if c == nil {
return
}
c.cancel()
}
@@ -162,12 +165,12 @@ type jwtCacheFillerController struct {
// Sync implements controllerlib.Syncer.
func (c *jwtCacheFillerController) Sync(ctx controllerlib.Context) error {
obj, err := c.jwtAuthenticators.Lister().Get(ctx.Key.Name)
if err != nil && apierrors.IsNotFound(err) {
c.log.Info("Sync() found that the JWTAuthenticator does not exist yet or was deleted")
return nil
}
if err != nil {
// no unit test for this failure
return fmt.Errorf("failed to get JWTAuthenticator %s/%s: %w", ctx.Key.Namespace, ctx.Key.Name, err)
}
@@ -179,33 +182,29 @@ func (c *jwtCacheFillerController) Sync(ctx controllerlib.Context) error {
// If this authenticator already exists, then only recreate it if is different from the desired
// authenticator. We don't want to be creating a new authenticator for every resync period.
//
// If we do need to recreate the authenticator, then make sure cancel the old one to avoid
// goroutine leaks.
if value := c.cache.Get(cacheKey); value != nil {
jwtAuthenticator := c.extractValueAsJWTAuthenticator(value)
if jwtAuthenticator != nil {
if reflect.DeepEqual(jwtAuthenticator.spec, &obj.Spec) {
c.log.WithValues("jwtAuthenticator", klog.KObj(obj), "issuer", obj.Spec.Issuer).Info("actual jwt authenticator and desired jwt authenticator are the same")
return nil
}
jwtAuthenticator.Close()
var jwtAuthenticatorFromCache *cachedJWTAuthenticator
if valueFromCache := c.cache.Get(cacheKey); valueFromCache != nil {
jwtAuthenticatorFromCache = c.cacheValueAsJWTAuthenticator(valueFromCache)
if jwtAuthenticatorFromCache != nil && reflect.DeepEqual(jwtAuthenticatorFromCache.spec, &obj.Spec) {
c.log.WithValues("jwtAuthenticator", klog.KObj(obj), "issuer", obj.Spec.Issuer).
Info("actual jwt authenticator and desired jwt authenticator are the same")
// Stop, no more work to be done. This authenticator is already validated and cached.
return nil
}
}
conditions := make([]*metav1.Condition, 0)
specCopy := obj.Spec.DeepCopy()
var errs []error
rootCAs, conditions, tlsOk := c.validateTLS(specCopy.TLS, conditions)
_, conditions, issuerOk := c.validateIssuer(specCopy.Issuer, conditions)
rootCAs, conditions, tlsOk := c.validateTLSBundle(obj.Spec.TLS, conditions)
_, conditions, issuerOk := c.validateIssuer(obj.Spec.Issuer, conditions)
okSoFar := tlsOk && issuerOk
client := phttp.Default(rootCAs)
client.Timeout = 30 * time.Second // copied from Kube OIDC code
coreOSCtx := coreosoidc.ClientContext(context.Background(), client)
pJSON, provider, conditions, providerErr := c.validateProviderDiscovery(coreOSCtx, specCopy.Issuer, conditions, okSoFar)
pJSON, provider, conditions, providerErr := c.validateProviderDiscovery(coreOSCtx, obj.Spec.Issuer, conditions, okSoFar)
errs = append(errs, providerErr)
okSoFar = okSoFar && providerErr == nil
@@ -217,21 +216,29 @@ func (c *jwtCacheFillerController) Sync(ctx controllerlib.Context) error {
errs = append(errs, jwksFetchErr)
okSoFar = okSoFar && jwksFetchErr == nil
// Make a deep copy of the spec so we aren't storing pointers to something that the informer cache
// may mutate! We don't store status as status is derived from spec.
cachedAuthenticator, conditions, err := c.newCachedJWTAuthenticator(
newJWTAuthenticatorForCache, conditions, err := c.newCachedJWTAuthenticator(
client,
obj.Spec.DeepCopy(),
obj.Spec.DeepCopy(), // deep copy to avoid caching original object
keySet,
conditions,
okSoFar)
errs = append(errs, err)
if !conditionsutil.HadErrorCondition(conditions) {
c.cache.Store(cacheKey, cachedAuthenticator)
c.log.Info("added new jwt authenticator", "jwtAuthenticator", klog.KObj(obj), "issuer", obj.Spec.Issuer)
if conditionsutil.HadErrorCondition(conditions) {
// The authenticator was determined to be invalid. Remove it from the cache, in case it was previously
// validated and cached. Do not allow an old, previously validated spec of the authenticator to continue
// being used for authentication.
c.cache.Delete(cacheKey)
} else {
c.cache.Store(cacheKey, newJWTAuthenticatorForCache)
c.log.WithValues("jwtAuthenticator", klog.KObj(obj), "issuer", obj.Spec.Issuer).
Info("added new jwt authenticator")
}
// In case we just overwrote or deleted the authenticator from the cache, clean up the old instance
// to avoid leaking goroutines. It's safe to call Close() on nil.
jwtAuthenticatorFromCache.Close()
err = c.updateStatus(ctx.Context, obj, conditions)
errs = append(errs, err)
@@ -243,7 +250,7 @@ func (c *jwtCacheFillerController) Sync(ctx controllerlib.Context) error {
return utilerrors.NewAggregate(errs)
}
func (c *jwtCacheFillerController) extractValueAsJWTAuthenticator(value authncache.Value) *cachedJWTAuthenticator {
func (c *jwtCacheFillerController) cacheValueAsJWTAuthenticator(value authncache.Value) *cachedJWTAuthenticator {
jwtAuthenticator, ok := value.(*cachedJWTAuthenticator)
if !ok {
actualType := "<nil>"
@@ -256,7 +263,7 @@ func (c *jwtCacheFillerController) extractValueAsJWTAuthenticator(value authncac
return jwtAuthenticator
}
func (c *jwtCacheFillerController) validateTLS(tlsSpec *authenticationv1alpha1.TLSSpec, conditions []*metav1.Condition) (*x509.CertPool, []*metav1.Condition, bool) {
func (c *jwtCacheFillerController) validateTLSBundle(tlsSpec *authenticationv1alpha1.TLSSpec, conditions []*metav1.Condition) (*x509.CertPool, []*metav1.Condition, bool) {
rootCAs, _, err := pinnipedcontroller.BuildCertPoolAuth(tlsSpec)
if err != nil {
msg := fmt.Sprintf("%s: %s", "invalid TLS configuration", err.Error())

View File

@@ -1143,6 +1143,58 @@ func TestController(t *testing.T) {
},
wantCacheEntries: 0,
},
{
name: "previously valid cached authenticator's spec changes and becomes invalid (e.g. spec.issuer URL is invalid): loop will fail sync, will write failed and unknown status conditions, and will remove authenticator from cache",
cache: func(t *testing.T, cache *authncache.Cache, wantClose bool) {
cache.Store(
authncache.Key{
Name: "test-name",
Kind: "JWTAuthenticator",
APIGroup: authenticationv1alpha1.SchemeGroupVersion.Group,
},
newCacheValue(t, *someJWTAuthenticatorSpec, wantClose),
)
},
jwtAuthenticators: []runtime.Object{
&authenticationv1alpha1.JWTAuthenticator{
ObjectMeta: metav1.ObjectMeta{
Name: "test-name",
},
Spec: *invalidIssuerJWTAuthenticatorSpec,
},
},
syncKey: controllerlib.Key{Name: "test-name"},
wantActions: func() []coretesting.Action {
updateStatusAction := coretesting.NewUpdateAction(jwtAuthenticatorsGVR, "", &authenticationv1alpha1.JWTAuthenticator{
ObjectMeta: metav1.ObjectMeta{
Name: "test-name",
},
Spec: *invalidIssuerJWTAuthenticatorSpec,
Status: authenticationv1alpha1.JWTAuthenticatorStatus{
Conditions: conditionstestutil.Replace(
allHappyConditionsSuccess(goodIssuer, frozenMetav1Now, 0),
[]metav1.Condition{
sadReadyCondition(frozenMetav1Now, 0),
sadIssuerURLValidInvalid("https://.café .com/café/café/café/coffee", frozenMetav1Now, 0),
unknownDiscoveryURLValid(frozenMetav1Now, 0),
unknownAuthenticatorValid(frozenMetav1Now, 0),
unknownJWKSURLValid(frozenMetav1Now, 0),
unknownJWKSFetch(frozenMetav1Now, 0),
},
),
Phase: "Error",
},
})
updateStatusAction.Subresource = "status"
return []coretesting.Action{
coretesting.NewListAction(jwtAuthenticatorsGVR, jwtAUthenticatorGVK, "", metav1.ListOptions{}),
coretesting.NewWatchAction(jwtAuthenticatorsGVR, "", metav1.ListOptions{}),
updateStatusAction,
}
},
wantCacheEntries: 0, // removed from cache
wantClose: true, // the removed cache entry was also closed
},
{
name: "validateIssuer: parsing error (spec.issuer URL is invalid): loop will fail sync, will write failed and unknown status conditions, but will not enqueue a resync due to user config error",
jwtAuthenticators: []runtime.Object{

View File

@@ -10,6 +10,7 @@ import (
"crypto/x509"
"fmt"
"net/url"
"reflect"
"time"
k8sauthv1beta1 "k8s.io/api/authentication/v1beta1"
@@ -56,6 +57,11 @@ const (
msgUnableToValidate = "unable to validate; see other conditions for details"
)
type cachedWebhookAuthenticator struct {
authenticator.Token
spec *authenticationv1alpha1.WebhookAuthenticatorSpec
}
// New instantiates a new controllerlib.Controller which will populate the provided authncache.Cache.
func New(
cache *authncache.Cache,
@@ -103,19 +109,38 @@ func (c *webhookCacheFillerController) Sync(ctx controllerlib.Context) error {
return fmt.Errorf("failed to get WebhookAuthenticator %s/%s: %w", ctx.Key.Namespace, ctx.Key.Name, err)
}
cacheKey := authncache.Key{
APIGroup: authenticationv1alpha1.GroupName,
Kind: "WebhookAuthenticator",
Name: ctx.Key.Name,
}
// If this authenticator already exists, then only recreate it if is different from the desired
// authenticator. We don't want to be creating a new authenticator for every resync period.
if valueFromCache := c.cache.Get(cacheKey); valueFromCache != nil {
webhookAuthenticatorFromCache := c.cacheValueAsWebhookAuthenticator(valueFromCache)
if webhookAuthenticatorFromCache != nil && reflect.DeepEqual(webhookAuthenticatorFromCache.spec, &obj.Spec) {
c.log.WithValues("webhookAuthenticator", klog.KObj(obj), "endpoint", obj.Spec.Endpoint).
Info("actual webhook authenticator and desired webhook authenticator are the same")
// Stop, no more work to be done. This authenticator is already validated and cached.
return nil
}
}
conditions := make([]*metav1.Condition, 0)
var errs []error
certPool, pemBytes, conditions, tlsBundleOk := c.validateTLSBundle(obj.Spec.TLS, conditions)
endpointHostPort, conditions, endpointOk := c.validateEndpoint(obj.Spec.Endpoint, conditions)
okSoFar := tlsBundleOk && endpointOk
conditions, tlsNegotiateErr := c.validateConnection(certPool, endpointHostPort, conditions, okSoFar)
errs = append(errs, tlsNegotiateErr)
okSoFar = okSoFar && tlsNegotiateErr == nil
webhookAuthenticator, conditions, err := newWebhookAuthenticator(
newWebhookAuthenticatorForCache, conditions, err := newWebhookAuthenticator(
// Note that we use the whole URL when constructing the webhook client,
// not just the host and port that ew validated above. We need the path, etc.
// not just the host and port that we validated above. We need the path, etc.
obj.Spec.Endpoint,
pemBytes,
conditions,
@@ -123,13 +148,18 @@ func (c *webhookCacheFillerController) Sync(ctx controllerlib.Context) error {
)
errs = append(errs, err)
if !conditionsutil.HadErrorCondition(conditions) {
c.cache.Store(authncache.Key{
APIGroup: authenticationv1alpha1.GroupName,
Kind: "WebhookAuthenticator",
Name: ctx.Key.Name,
}, webhookAuthenticator)
c.log.WithValues("webhook", klog.KObj(obj), "endpoint", obj.Spec.Endpoint).Info("added new webhook authenticator")
if conditionsutil.HadErrorCondition(conditions) {
// The authenticator was determined to be invalid. Remove it from the cache, in case it was previously
// validated and cached. Do not allow an old, previously validated spec of the authenticator to continue
// being used for authentication.
c.cache.Delete(cacheKey)
} else {
c.cache.Store(cacheKey, &cachedWebhookAuthenticator{
Token: newWebhookAuthenticatorForCache,
spec: obj.Spec.DeepCopy(), // deep copy to avoid caching original object
})
c.log.WithValues("webhook", klog.KObj(obj), "endpoint", obj.Spec.Endpoint).
Info("added new webhook authenticator")
}
err = c.updateStatus(ctx.Context, obj, conditions)
@@ -143,6 +173,19 @@ func (c *webhookCacheFillerController) Sync(ctx controllerlib.Context) error {
return utilerrors.NewAggregate(errs)
}
func (c *webhookCacheFillerController) cacheValueAsWebhookAuthenticator(value authncache.Value) *cachedWebhookAuthenticator {
webhookAuthenticator, ok := value.(*cachedWebhookAuthenticator)
if !ok {
actualType := "<nil>"
if t := reflect.TypeOf(value); t != nil {
actualType = t.String()
}
c.log.WithValues("actualType", actualType).Info("wrong webhook authenticator type in cache")
return nil
}
return webhookAuthenticator
}
// newWebhookAuthenticator creates a webhook from the provided API server url and caBundle
// used to validate TLS connections.
func newWebhookAuthenticator(

View File

@@ -24,6 +24,7 @@ import (
metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
"k8s.io/apimachinery/pkg/runtime"
"k8s.io/apimachinery/pkg/runtime/schema"
"k8s.io/apiserver/pkg/authentication/authenticator"
coretesting "k8s.io/client-go/testing"
clocktesting "k8s.io/utils/clock/testing"
"k8s.io/utils/ptr"
@@ -360,6 +361,7 @@ func TestController(t *testing.T) {
tests := []struct {
name string
cache func(*testing.T, *authncache.Cache)
syncKey controllerlib.Key
webhooks []runtime.Object
// for modifying the clients to hack in arbitrary api responses
@@ -424,7 +426,122 @@ func TestController(t *testing.T) {
wantCacheEntries: 1,
},
{
name: "Sync: changed WebhookAuthenticator: loop will update timestamps only on relevant statuses",
name: "Sync: valid and unchanged WebhookAuthenticator which was already cached: skips any updates to status or cache",
cache: func(t *testing.T, cache *authncache.Cache) {
cache.Store(
authncache.Key{
Name: "test-name",
Kind: "WebhookAuthenticator",
APIGroup: authenticationv1alpha1.SchemeGroupVersion.Group,
},
&cachedWebhookAuthenticator{spec: &goodWebhookAuthenticatorSpecWithCA},
)
},
syncKey: controllerlib.Key{Name: "test-name"},
webhooks: []runtime.Object{
&authenticationv1alpha1.WebhookAuthenticator{
ObjectMeta: metav1.ObjectMeta{
Name: "test-name",
},
Spec: goodWebhookAuthenticatorSpecWithCA,
Status: authenticationv1alpha1.WebhookAuthenticatorStatus{
Conditions: allHappyConditionsSuccess(goodWebhookDefaultServingCertEndpoint, frozenMetav1Now, 0),
Phase: "Ready",
},
},
},
wantLogs: []map[string]any{
{
"level": "info",
"timestamp": "2099-08-08T13:57:36.123456Z",
"logger": "webhookcachefiller-controller",
"message": "actual webhook authenticator and desired webhook authenticator are the same",
"endpoint": goodWebhookDefaultServingCertEndpoint,
"webhook": map[string]any{
"name": "test-name",
},
},
},
wantActions: func() []coretesting.Action {
return []coretesting.Action{
coretesting.NewListAction(webhookAuthenticatorGVR, webhookAuthenticatorGVK, "", metav1.ListOptions{}),
coretesting.NewWatchAction(webhookAuthenticatorGVR, "", metav1.ListOptions{}),
}
},
wantCacheEntries: 1,
},
{
name: "Sync: authenticator update when cached authenticator is different type: loop will complete successfully and update status conditions.",
cache: func(t *testing.T, cache *authncache.Cache) {
cache.Store(
authncache.Key{
Name: "test-name",
Kind: "WebhookAuthenticator",
APIGroup: authenticationv1alpha1.SchemeGroupVersion.Group,
},
struct{ authenticator.Token }{},
)
},
syncKey: controllerlib.Key{Name: "test-name"},
webhooks: []runtime.Object{
&authenticationv1alpha1.WebhookAuthenticator{
ObjectMeta: metav1.ObjectMeta{
Name: "test-name",
},
Spec: goodWebhookAuthenticatorSpecWithCA,
},
},
wantLogs: []map[string]any{
{
"level": "info",
"timestamp": "2099-08-08T13:57:36.123456Z",
"logger": "webhookcachefiller-controller",
"message": "wrong webhook authenticator type in cache",
"actualType": "struct { authenticator.Token }",
},
{
"level": "info",
"timestamp": "2099-08-08T13:57:36.123456Z",
"logger": "webhookcachefiller-controller",
"message": "added new webhook authenticator",
"endpoint": goodWebhookDefaultServingCertEndpoint,
"webhook": map[string]any{
"name": "test-name",
},
},
},
wantActions: func() []coretesting.Action {
updateStatusAction := coretesting.NewUpdateAction(webhookAuthenticatorGVR, "", &authenticationv1alpha1.WebhookAuthenticator{
ObjectMeta: metav1.ObjectMeta{
Name: "test-name",
},
Spec: goodWebhookAuthenticatorSpecWithCA,
Status: authenticationv1alpha1.WebhookAuthenticatorStatus{
Conditions: allHappyConditionsSuccess(goodWebhookDefaultServingCertEndpoint, frozenMetav1Now, 0),
Phase: "Ready",
},
})
updateStatusAction.Subresource = "status"
return []coretesting.Action{
coretesting.NewListAction(webhookAuthenticatorGVR, webhookAuthenticatorGVK, "", metav1.ListOptions{}),
coretesting.NewWatchAction(webhookAuthenticatorGVR, "", metav1.ListOptions{}),
updateStatusAction,
}
},
wantCacheEntries: 1,
},
{
name: "Sync: changed WebhookAuthenticator: loop will update timestamps only on relevant statuses",
cache: func(t *testing.T, cache *authncache.Cache) {
cache.Store(
authncache.Key{
Name: "test-name",
Kind: "WebhookAuthenticator",
APIGroup: authenticationv1alpha1.SchemeGroupVersion.Group,
},
&cachedWebhookAuthenticator{spec: &goodWebhookAuthenticatorSpecWith404Endpoint},
)
},
syncKey: controllerlib.Key{Name: "test-name"},
webhooks: []runtime.Object{
&authenticationv1alpha1.WebhookAuthenticator{
@@ -662,6 +779,60 @@ func TestController(t *testing.T) {
},
wantCacheEntries: 0,
},
{
name: "previously valid cached authenticator's spec changes and becomes invalid (e.g. spec.issuer URL is invalid): loop will fail sync, will write failed and unknown status conditions, and will remove authenticator from cache",
cache: func(t *testing.T, cache *authncache.Cache) {
cache.Store(
authncache.Key{
Name: "test-name",
Kind: "WebhookAuthenticator",
APIGroup: authenticationv1alpha1.SchemeGroupVersion.Group,
},
&cachedWebhookAuthenticator{spec: &goodWebhookAuthenticatorSpecWithCA},
)
},
syncKey: controllerlib.Key{Name: "test-name"},
webhooks: []runtime.Object{
&authenticationv1alpha1.WebhookAuthenticator{
ObjectMeta: metav1.ObjectMeta{
Name: "test-name",
},
Spec: authenticationv1alpha1.WebhookAuthenticatorSpec{
Endpoint: badEndpointInvalidURL,
},
},
},
wantActions: func() []coretesting.Action {
updateStatusAction := coretesting.NewUpdateAction(webhookAuthenticatorGVR, "", &authenticationv1alpha1.WebhookAuthenticator{
ObjectMeta: metav1.ObjectMeta{
Name: "test-name",
},
Spec: authenticationv1alpha1.WebhookAuthenticatorSpec{
Endpoint: badEndpointInvalidURL,
},
Status: authenticationv1alpha1.WebhookAuthenticatorStatus{
Conditions: conditionstestutil.Replace(
allHappyConditionsSuccess(goodWebhookDefaultServingCertEndpoint, frozenMetav1Now, 0),
[]metav1.Condition{
happyTLSConfigurationValidNoCA(frozenMetav1Now, 0),
sadEndpointURLValid("https://.café .com/café/café/café/coffee", frozenMetav1Now, 0),
unknownWebhookConnectionValid(frozenMetav1Now, 0),
unknownAuthenticatorValid(frozenMetav1Now, 0),
sadReadyCondition(frozenMetav1Now, 0),
},
),
Phase: "Error",
},
})
updateStatusAction.Subresource = "status"
return []coretesting.Action{
coretesting.NewListAction(webhookAuthenticatorGVR, webhookAuthenticatorGVK, "", metav1.ListOptions{}),
coretesting.NewWatchAction(webhookAuthenticatorGVR, "", metav1.ListOptions{}),
updateStatusAction,
}
},
wantCacheEntries: 0, // removed from cache
},
{
name: "validateEndpoint: parsing error (spec.endpoint URL is invalid) will fail sync loop and will report failed and unknown conditions and Error phase, but will not enqueue a resync due to user config error",
syncKey: controllerlib.Key{Name: "test-name"},
@@ -1319,6 +1490,10 @@ func TestController(t *testing.T) {
var log bytes.Buffer
logger := plog.TestLogger(t, &log)
if tt.cache != nil {
tt.cache(t, cache)
}
controller := New(
cache,
pinnipedAPIClient,