feat: kubesphere 4.0 (#6115)

* feat: kubesphere 4.0

Signed-off-by: ci-bot <ci-bot@kubesphere.io>

* feat: kubesphere 4.0

Signed-off-by: ci-bot <ci-bot@kubesphere.io>

---------

Signed-off-by: ci-bot <ci-bot@kubesphere.io>
Co-authored-by: ks-ci-bot <ks-ci-bot@example.com>
Co-authored-by: joyceliu <joyceliu@yunify.com>

vendor/k8s.io/apiserver/pkg/admission/plugin/validatingadmissionpolicy/admission.go

@@ -23,6 +23,7 @@ import (
 	"io"
 
 	"k8s.io/apimachinery/pkg/api/meta"
+	"k8s.io/apiserver/pkg/authorization/authorizer"
 	"k8s.io/apiserver/pkg/features"
 	"k8s.io/client-go/dynamic"
 	"k8s.io/component-base/featuregate"
@@ -71,6 +72,7 @@ type celAdmissionPlugin struct {
 	restMapper      meta.RESTMapper
 	dynamicClient   dynamic.Interface
 	stopCh          <-chan struct{}
+	authorizer      authorizer.Authorizer
 }
 
 var _ initializer.WantsExternalKubeInformerFactory = &celAdmissionPlugin{}
@@ -78,7 +80,7 @@ var _ initializer.WantsExternalKubeClientSet = &celAdmissionPlugin{}
 var _ initializer.WantsRESTMapper = &celAdmissionPlugin{}
 var _ initializer.WantsDynamicClient = &celAdmissionPlugin{}
 var _ initializer.WantsDrainedNotification = &celAdmissionPlugin{}
-
+var _ initializer.WantsAuthorizer = &celAdmissionPlugin{}
 var _ admission.InitializationValidator = &celAdmissionPlugin{}
 var _ admission.ValidationInterface = &celAdmissionPlugin{}
 
@@ -108,6 +110,9 @@ func (c *celAdmissionPlugin) SetDrainedNotification(stopCh <-chan struct{}) {
 	c.stopCh = stopCh
 }
 
+func (c *celAdmissionPlugin) SetAuthorizer(authorizer authorizer.Authorizer) {
+	c.authorizer = authorizer
+}
 func (c *celAdmissionPlugin) InspectFeatureGates(featureGates featuregate.FeatureGate) {
 	if featureGates.Enabled(features.ValidatingAdmissionPolicy) {
 		c.enabled = true
@@ -138,7 +143,10 @@ func (c *celAdmissionPlugin) ValidateInitialization() error {
 	if c.stopCh == nil {
 		return errors.New("missing stop channel")
 	}
-	c.evaluator = NewAdmissionController(c.informerFactory, c.client, c.restMapper, c.dynamicClient)
+	if c.authorizer == nil {
+		return errors.New("missing authorizer")
+	}
+	c.evaluator = NewAdmissionController(c.informerFactory, c.client, c.restMapper, c.dynamicClient, c.authorizer)
 	if err := c.evaluator.ValidateInitialization(); err != nil {
 		return err
 	}

vendor/k8s.io/apiserver/pkg/admission/plugin/validatingadmissionpolicy/caching_authorizer.go

@@ -0,0 +1,133 @@
+/*
+Copyright 2023 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 validatingadmissionpolicy
+
+import (
+	"context"
+	"encoding/json"
+	"sort"
+	"strings"
+
+	"k8s.io/apiserver/pkg/authentication/user"
+	"k8s.io/apiserver/pkg/authorization/authorizer"
+)
+
+type authzResult struct {
+	authorized authorizer.Decision
+	reason     string
+	err        error
+}
+
+type cachingAuthorizer struct {
+	authorizer authorizer.Authorizer
+	decisions  map[string]authzResult
+}
+
+func newCachingAuthorizer(in authorizer.Authorizer) authorizer.Authorizer {
+	return &cachingAuthorizer{
+		authorizer: in,
+		decisions:  make(map[string]authzResult),
+	}
+}
+
+// The attribute accessors known to cache key construction. If this fails to compile, the cache
+// implementation may need to be updated.
+var _ authorizer.Attributes = (interface {
+	GetUser() user.Info
+	GetVerb() string
+	IsReadOnly() bool
+	GetNamespace() string
+	GetResource() string
+	GetSubresource() string
+	GetName() string
+	GetAPIGroup() string
+	GetAPIVersion() string
+	IsResourceRequest() bool
+	GetPath() string
+})(nil)
+
+// The user info accessors known to cache key construction. If this fails to compile, the cache
+// implementation may need to be updated.
+var _ user.Info = (interface {
+	GetName() string
+	GetUID() string
+	GetGroups() []string
+	GetExtra() map[string][]string
+})(nil)
+
+// Authorize returns an authorization decision by delegating to another Authorizer. If an equivalent
+// check has already been performed, a cached result is returned. Not safe for concurrent use.
+func (ca *cachingAuthorizer) Authorize(ctx context.Context, a authorizer.Attributes) (authorizer.Decision, string, error) {
+	serializableAttributes := authorizer.AttributesRecord{
+		Verb:            a.GetVerb(),
+		Namespace:       a.GetNamespace(),
+		APIGroup:        a.GetAPIGroup(),
+		APIVersion:      a.GetAPIVersion(),
+		Resource:        a.GetResource(),
+		Subresource:     a.GetSubresource(),
+		Name:            a.GetName(),
+		ResourceRequest: a.IsResourceRequest(),
+		Path:            a.GetPath(),
+	}
+
+	if u := a.GetUser(); u != nil {
+		di := &user.DefaultInfo{
+			Name: u.GetName(),
+			UID:  u.GetUID(),
+		}
+
+		// Differently-ordered groups or extras could cause otherwise-equivalent checks to
+		// have distinct cache keys.
+		if groups := u.GetGroups(); len(groups) > 0 {
+			di.Groups = make([]string, len(groups))
+			copy(di.Groups, groups)
+			sort.Strings(di.Groups)
+		}
+
+		if extra := u.GetExtra(); len(extra) > 0 {
+			di.Extra = make(map[string][]string, len(extra))
+			for k, vs := range extra {
+				vdupe := make([]string, len(vs))
+				copy(vdupe, vs)
+				sort.Strings(vdupe)
+				di.Extra[k] = vdupe
+			}
+		}
+
+		serializableAttributes.User = di
+	}
+
+	var b strings.Builder
+	if err := json.NewEncoder(&b).Encode(serializableAttributes); err != nil {
+		return authorizer.DecisionNoOpinion, "", err
+	}
+	key := b.String()
+
+	if cached, ok := ca.decisions[key]; ok {
+		return cached.authorized, cached.reason, cached.err
+	}
+
+	authorized, reason, err := ca.authorizer.Authorize(ctx, a)
+
+	ca.decisions[key] = authzResult{
+		authorized: authorized,
+		reason:     reason,
+		err:        err,
+	}
+
+	return authorized, reason, err
+}

vendor/k8s.io/apiserver/pkg/admission/plugin/validatingadmissionpolicy/compiler.go

@@ -1,231 +0,0 @@
-/*
-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 validatingadmissionpolicy
-
-import (
-	"sync"
-
-	"github.com/google/cel-go/cel"
-
-	apiservercel "k8s.io/apiserver/pkg/cel"
-	"k8s.io/apiserver/pkg/cel/library"
-)
-
-const (
-	ObjectVarName    = "object"
-	OldObjectVarName = "oldObject"
-	ParamsVarName    = "params"
-	RequestVarName   = "request"
-
-	checkFrequency = 100
-)
-
-type envs struct {
-	noParams   *cel.Env
-	withParams *cel.Env
-}
-
-var (
-	initEnvsOnce sync.Once
-	initEnvs     *envs
-	initEnvsErr  error
-)
-
-func getEnvs() (*envs, error) {
-	initEnvsOnce.Do(func() {
-		base, err := buildBaseEnv()
-		if err != nil {
-			initEnvsErr = err
-			return
-		}
-		noParams, err := buildNoParamsEnv(base)
-		if err != nil {
-			initEnvsErr = err
-			return
-		}
-		withParams, err := buildWithParamsEnv(noParams)
-		if err != nil {
-			initEnvsErr = err
-			return
-		}
-		initEnvs = &envs{noParams: noParams, withParams: withParams}
-	})
-	return initEnvs, initEnvsErr
-}
-
-// This is a similar code as in k8s.io/apiextensions-apiserver/pkg/apiserver/schema/cel/compilation.go
-// If any changes are made here, consider to make the same changes there as well.
-func buildBaseEnv() (*cel.Env, error) {
-	var opts []cel.EnvOption
-	opts = append(opts, cel.HomogeneousAggregateLiterals())
-	// Validate function declarations once during base env initialization,
-	// so they don't need to be evaluated each time a CEL rule is compiled.
-	// This is a relatively expensive operation.
-	opts = append(opts, cel.EagerlyValidateDeclarations(true), cel.DefaultUTCTimeZone(true))
-	opts = append(opts, library.ExtensionLibs...)
-
-	return cel.NewEnv(opts...)
-}
-
-func buildNoParamsEnv(baseEnv *cel.Env) (*cel.Env, error) {
-	var propDecls []cel.EnvOption
-	reg := apiservercel.NewRegistry(baseEnv)
-
-	requestType := buildRequestType()
-	rt, err := apiservercel.NewRuleTypes(requestType.TypeName(), requestType, reg)
-	if err != nil {
-		return nil, err
-	}
-	if rt == nil {
-		return nil, nil
-	}
-	opts, err := rt.EnvOptions(baseEnv.TypeProvider())
-	if err != nil {
-		return nil, err
-	}
-	propDecls = append(propDecls, cel.Variable(ObjectVarName, cel.DynType))
-	propDecls = append(propDecls, cel.Variable(OldObjectVarName, cel.DynType))
-	propDecls = append(propDecls, cel.Variable(RequestVarName, requestType.CelType()))
-
-	opts = append(opts, propDecls...)
-	env, err := baseEnv.Extend(opts...)
-	if err != nil {
-		return nil, err
-	}
-	return env, nil
-}
-
-func buildWithParamsEnv(noParams *cel.Env) (*cel.Env, error) {
-	return noParams.Extend(cel.Variable(ParamsVarName, cel.DynType))
-}
-
-// buildRequestType generates a DeclType for AdmissionRequest. This may be replaced with a utility that
-// converts the native type definition to apiservercel.DeclType once such a utility becomes available.
-// The 'uid' field is omitted since it is not needed for in-process admission review.
-// The 'object' and 'oldObject' fields are omitted since they are exposed as root level CEL variables.
-func buildRequestType() *apiservercel.DeclType {
-	field := func(name string, declType *apiservercel.DeclType, required bool) *apiservercel.DeclField {
-		return apiservercel.NewDeclField(name, declType, required, nil, nil)
-	}
-	fields := func(fields ...*apiservercel.DeclField) map[string]*apiservercel.DeclField {
-		result := make(map[string]*apiservercel.DeclField, len(fields))
-		for _, f := range fields {
-			result[f.Name] = f
-		}
-		return result
-	}
-	gvkType := apiservercel.NewObjectType("kubernetes.GroupVersionKind", fields(
-		field("group", apiservercel.StringType, true),
-		field("version", apiservercel.StringType, true),
-		field("kind", apiservercel.StringType, true),
-	))
-	gvrType := apiservercel.NewObjectType("kubernetes.GroupVersionResource", fields(
-		field("group", apiservercel.StringType, true),
-		field("version", apiservercel.StringType, true),
-		field("resource", apiservercel.StringType, true),
-	))
-	userInfoType := apiservercel.NewObjectType("kubernetes.UserInfo", fields(
-		field("username", apiservercel.StringType, false),
-		field("uid", apiservercel.StringType, false),
-		field("groups", apiservercel.NewListType(apiservercel.StringType, -1), false),
-		field("extra", apiservercel.NewMapType(apiservercel.StringType, apiservercel.NewListType(apiservercel.StringType, -1), -1), false),
-	))
-	return apiservercel.NewObjectType("kubernetes.AdmissionRequest", fields(
-		field("kind", gvkType, true),
-		field("resource", gvrType, true),
-		field("subResource", apiservercel.StringType, false),
-		field("requestKind", gvkType, true),
-		field("requestResource", gvrType, true),
-		field("requestSubResource", apiservercel.StringType, false),
-		field("name", apiservercel.StringType, true),
-		field("namespace", apiservercel.StringType, false),
-		field("operation", apiservercel.StringType, true),
-		field("userInfo", userInfoType, true),
-		field("dryRun", apiservercel.BoolType, false),
-		field("options", apiservercel.DynType, false),
-	))
-}
-
-// CompilationResult represents a compiled ValidatingAdmissionPolicy validation expression.
-type CompilationResult struct {
-	Program cel.Program
-	Error   *apiservercel.Error
-}
-
-// CompileValidatingPolicyExpression returns a compiled vaalidating policy CEL expression.
-func CompileValidatingPolicyExpression(validationExpression string, hasParams bool) CompilationResult {
-	var env *cel.Env
-	envs, err := getEnvs()
-	if err != nil {
-		return CompilationResult{
-			Error: &apiservercel.Error{
-				Type:   apiservercel.ErrorTypeInternal,
-				Detail: "compiler initialization failed: " + err.Error(),
-			},
-		}
-	}
-	if hasParams {
-		env = envs.withParams
-	} else {
-		env = envs.noParams
-	}
-
-	ast, issues := env.Compile(validationExpression)
-	if issues != nil {
-		return CompilationResult{
-			Error: &apiservercel.Error{
-				Type:   apiservercel.ErrorTypeInvalid,
-				Detail: "compilation failed: " + issues.String(),
-			},
-		}
-	}
-	if ast.OutputType() != cel.BoolType {
-		return CompilationResult{
-			Error: &apiservercel.Error{
-				Type:   apiservercel.ErrorTypeInvalid,
-				Detail: "cel expression must evaluate to a bool",
-			},
-		}
-	}
-
-	_, err = cel.AstToCheckedExpr(ast)
-	if err != nil {
-		// should be impossible since env.Compile returned no issues
-		return CompilationResult{
-			Error: &apiservercel.Error{
-				Type:   apiservercel.ErrorTypeInternal,
-				Detail: "unexpected compilation error: " + err.Error(),
-			},
-		}
-	}
-	prog, err := env.Program(ast,
-		cel.EvalOptions(cel.OptOptimize),
-		cel.OptimizeRegex(library.ExtensionLibRegexOptimizations...),
-		cel.InterruptCheckFrequency(checkFrequency),
-	)
-	if err != nil {
-		return CompilationResult{
-			Error: &apiservercel.Error{
-				Type:   apiservercel.ErrorTypeInvalid,
-				Detail: "program instantiation failed: " + err.Error(),
-			},
-		}
-	}
-	return CompilationResult{
-		Program: prog,
-	}
-}

vendor/k8s.io/apiserver/pkg/admission/plugin/validatingadmissionpolicy/controller.go

@@ -20,25 +20,34 @@ import (
 	"context"
 	"errors"
 	"fmt"
+	"strings"
 	"sync"
 	"sync/atomic"
+	"time"
 
-	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
-
-	"k8s.io/apiserver/pkg/admission/plugin/validatingadmissionpolicy/matching"
-
-	"k8s.io/api/admissionregistration/v1alpha1"
+	"k8s.io/api/admissionregistration/v1beta1"
+	v1 "k8s.io/api/core/v1"
 	k8serrors "k8s.io/apimachinery/pkg/api/errors"
 	"k8s.io/apimachinery/pkg/api/meta"
-	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/apimachinery/pkg/runtime/schema"
+	utiljson "k8s.io/apimachinery/pkg/util/json"
 	utilruntime "k8s.io/apimachinery/pkg/util/runtime"
 	"k8s.io/apimachinery/pkg/util/sets"
+	"k8s.io/apimachinery/pkg/util/wait"
 	"k8s.io/apiserver/pkg/admission"
 	celmetrics "k8s.io/apiserver/pkg/admission/cel"
 	"k8s.io/apiserver/pkg/admission/plugin/validatingadmissionpolicy/internal/generic"
+	"k8s.io/apiserver/pkg/admission/plugin/validatingadmissionpolicy/matching"
+	celconfig "k8s.io/apiserver/pkg/apis/cel"
+	"k8s.io/apiserver/pkg/authorization/authorizer"
+	"k8s.io/apiserver/pkg/warning"
 	"k8s.io/client-go/dynamic"
 	"k8s.io/client-go/informers"
 	"k8s.io/client-go/kubernetes"
+	"k8s.io/client-go/tools/cache"
+	"k8s.io/klog/v2"
 )
 
 var _ CELPolicyEvaluator = &celAdmissionController{}
@@ -46,44 +55,34 @@ var _ CELPolicyEvaluator = &celAdmissionController{}
 // celAdmissionController is the top-level controller for admission control using CEL
 // it is responsible for watching policy definitions, bindings, and config param CRDs
 type celAdmissionController struct {
-	// Context under which the controller runs
-	runningContext context.Context
+	// Controller which manages book-keeping for the cluster's dynamic policy
+	// information.
+	policyController *policyController
 
-	policyDefinitionsController generic.Controller[*v1alpha1.ValidatingAdmissionPolicy]
-	policyBindingController     generic.Controller[*v1alpha1.ValidatingAdmissionPolicyBinding]
+	// atomic []policyData
+	// list of every known policy definition, and all informatoin required to
+	// validate its bindings against an object.
+	// A snapshot of the current policy configuration is synced with this field
+	// asynchronously
+	definitions atomic.Value
 
-	// dynamicclient used to create informers to watch the param crd types
-	dynamicClient dynamic.Interface
-	restMapper    meta.RESTMapper
+	authz authorizer.Authorizer
+}
 
-	// Provided to the policy's Compile function as an injected dependency to
-	// assist with compiling its expressions to CEL
-	validatorCompiler ValidatorCompiler
+// Everything someone might need to validate a single ValidatingPolicyDefinition
+// against all of its registered bindings.
+type policyData struct {
+	definitionInfo
+	paramInfo
+	bindings []bindingInfo
+}
 
-	// Lock which protects:
-	//	- definitionInfo
-	//  - bindingInfos
-	//  - paramCRDControllers
-	//  - definitionsToBindings
-	// All other fields should be assumed constant
-	mutex sync.RWMutex
-
-	// controller and metadata
-	paramsCRDControllers map[v1alpha1.ParamKind]*paramInfo
-
-	// Index for each definition namespace/name, contains all binding
-	// namespace/names known to exist for that definition
-	definitionInfo map[namespacedName]*definitionInfo
-
-	// Index for each bindings namespace/name. Contains compiled templates
-	// for the binding depending on the policy/param combination.
-	bindingInfos map[namespacedName]*bindingInfo
-
-	// Map from namespace/name of a definition to a set of namespace/name
-	// of bindings which depend on it.
-	// All keys must have at least one dependent binding
-	// All binding names MUST exist as a key bindingInfos
-	definitionsToBindings map[namespacedName]sets.Set[namespacedName]
+// contains the cel PolicyDecisions along with the ValidatingAdmissionPolicy and ValidatingAdmissionPolicyBinding
+// that determined the decision
+type policyDecisionWithMetadata struct {
+	PolicyDecision
+	Definition *v1beta1.ValidatingAdmissionPolicy
+	Binding    *v1beta1.ValidatingAdmissionPolicyBinding
 }
 
 // namespaceName is used as a key in definitionInfo and bindingInfos
@@ -99,25 +98,28 @@ type definitionInfo struct {
 
 	// Last value seen by this controller to be used in policy enforcement
 	// May not be nil
-	lastReconciledValue *v1alpha1.ValidatingAdmissionPolicy
+	lastReconciledValue *v1beta1.ValidatingAdmissionPolicy
 }
 
 type bindingInfo struct {
 	// Compiled CEL expression turned into an validator
-	validator atomic.Pointer[Validator]
+	validator Validator
 
 	// Last value seen by this controller to be used in policy enforcement
 	// May not be nil
-	lastReconciledValue *v1alpha1.ValidatingAdmissionPolicyBinding
+	lastReconciledValue *v1beta1.ValidatingAdmissionPolicyBinding
 }
 
 type paramInfo struct {
 	// Controller which is watching this param CRD
-	controller generic.Controller[*unstructured.Unstructured]
+	controller generic.Controller[runtime.Object]
 
 	// Function to call to stop the informer and clean up the controller
 	stop func()
 
+	// Whether this param is cluster or namespace scoped
+	scope meta.RESTScope
+
 	// Policy Definitions which refer to this param CRD
 	dependentDefinitions sets.Set[namespacedName]
 }
@@ -128,66 +130,48 @@ func NewAdmissionController(
 	client kubernetes.Interface,
 	restMapper meta.RESTMapper,
 	dynamicClient dynamic.Interface,
+	authz authorizer.Authorizer,
 ) CELPolicyEvaluator {
-	matcher := matching.NewMatcher(informerFactory.Core().V1().Namespaces().Lister(), client)
-	validatorCompiler := &CELValidatorCompiler{
-		Matcher: matcher,
+	return &celAdmissionController{
+		definitions: atomic.Value{},
+		policyController: newPolicyController(
+			restMapper,
+			client,
+			dynamicClient,
+			informerFactory,
+			nil,
+			NewMatcher(matching.NewMatcher(informerFactory.Core().V1().Namespaces().Lister(), client)),
+			generic.NewInformer[*v1beta1.ValidatingAdmissionPolicy](
+				informerFactory.Admissionregistration().V1beta1().ValidatingAdmissionPolicies().Informer()),
+			generic.NewInformer[*v1beta1.ValidatingAdmissionPolicyBinding](
+				informerFactory.Admissionregistration().V1beta1().ValidatingAdmissionPolicyBindings().Informer()),
+		),
+		authz: authz,
 	}
-	c := &celAdmissionController{
-		definitionInfo:        make(map[namespacedName]*definitionInfo),
-		bindingInfos:          make(map[namespacedName]*bindingInfo),
-		paramsCRDControllers:  make(map[v1alpha1.ParamKind]*paramInfo),
-		definitionsToBindings: make(map[namespacedName]sets.Set[namespacedName]),
-		dynamicClient:         dynamicClient,
-		validatorCompiler:     validatorCompiler,
-		restMapper:            restMapper,
-	}
-
-	c.policyDefinitionsController = generic.NewController(
-		generic.NewInformer[*v1alpha1.ValidatingAdmissionPolicy](
-			informerFactory.Admissionregistration().V1alpha1().ValidatingAdmissionPolicies().Informer()),
-		c.reconcilePolicyDefinition,
-		generic.ControllerOptions{
-			Workers: 1,
-			Name:    "cel-policy-definitions",
-		},
-	)
-	c.policyBindingController = generic.NewController(
-		generic.NewInformer[*v1alpha1.ValidatingAdmissionPolicyBinding](
-			informerFactory.Admissionregistration().V1alpha1().ValidatingAdmissionPolicyBindings().Informer()),
-		c.reconcilePolicyBinding,
-		generic.ControllerOptions{
-			Workers: 1,
-			Name:    "cel-policy-bindings",
-		},
-	)
-	return c
 }
 
 func (c *celAdmissionController) Run(stopCh <-chan struct{}) {
-	if c.runningContext != nil {
-		return
-	}
-
 	ctx, cancel := context.WithCancel(context.Background())
-
-	c.runningContext = ctx
-	defer func() {
-		c.runningContext = nil
-	}()
-
 	wg := sync.WaitGroup{}
 
 	wg.Add(1)
 	go func() {
 		defer wg.Done()
-		c.policyDefinitionsController.Run(ctx)
+		c.policyController.Run(ctx)
 	}()
 
 	wg.Add(1)
 	go func() {
 		defer wg.Done()
-		c.policyBindingController.Run(ctx)
+
+		// Wait indefinitely until policies/bindings are listed & handled before
+		// allowing policies to be refreshed
+		if !cache.WaitForNamedCacheSync("cel-admission-controller", ctx.Done(), c.policyController.HasSynced) {
+			return
+		}
+
+		// Loop every 1 second until context is cancelled, refreshing policies
+		wait.Until(c.refreshPolicies, 1*time.Second, ctx.Done())
 	}()
 
 	<-stopCh
@@ -195,31 +179,34 @@ func (c *celAdmissionController) Run(stopCh <-chan struct{}) {
 	wg.Wait()
 }
 
+const maxAuditAnnotationValueLength = 10 * 1024
+
 func (c *celAdmissionController) Validate(
 	ctx context.Context,
 	a admission.Attributes,
 	o admission.ObjectInterfaces,
 ) (err error) {
-	c.mutex.RLock()
-	defer c.mutex.RUnlock()
+	if !c.HasSynced() {
+		return admission.NewForbidden(a, fmt.Errorf("not yet ready to handle request"))
+	}
 
 	var deniedDecisions []policyDecisionWithMetadata
 
-	addConfigError := func(err error, definition *v1alpha1.ValidatingAdmissionPolicy, binding *v1alpha1.ValidatingAdmissionPolicyBinding) {
+	addConfigError := func(err error, definition *v1beta1.ValidatingAdmissionPolicy, binding *v1beta1.ValidatingAdmissionPolicyBinding) {
 		// we always default the FailurePolicy if it is unset and validate it in API level
-		var policy v1alpha1.FailurePolicyType
+		var policy v1beta1.FailurePolicyType
 		if definition.Spec.FailurePolicy == nil {
-			policy = v1alpha1.Fail
+			policy = v1beta1.Fail
 		} else {
 			policy = *definition.Spec.FailurePolicy
 		}
 
 		// apply FailurePolicy specified in ValidatingAdmissionPolicy, the default would be Fail
 		switch policy {
-		case v1alpha1.Ignore:
+		case v1beta1.Ignore:
 			// TODO: add metrics for ignored error here
 			return
-		case v1alpha1.Fail:
+		case v1beta1.Fail:
 			var message string
 			if binding == nil {
 				message = fmt.Errorf("failed to configure policy: %w", err).Error()
@@ -227,27 +214,37 @@ func (c *celAdmissionController) Validate(
 				message = fmt.Errorf("failed to configure binding: %w", err).Error()
 			}
 			deniedDecisions = append(deniedDecisions, policyDecisionWithMetadata{
-				policyDecision: policyDecision{
-					action:  actionDeny,
-					message: message,
+				PolicyDecision: PolicyDecision{
+					Action:  ActionDeny,
+					Message: message,
 				},
-				definition: definition,
-				binding:    binding,
+				Definition: definition,
+				Binding:    binding,
 			})
 		default:
 			deniedDecisions = append(deniedDecisions, policyDecisionWithMetadata{
-				policyDecision: policyDecision{
-					action:  actionDeny,
-					message: fmt.Errorf("unrecognized failure policy: '%v'", policy).Error(),
+				PolicyDecision: PolicyDecision{
+					Action:  ActionDeny,
+					Message: fmt.Errorf("unrecognized failure policy: '%v'", policy).Error(),
 				},
-				definition: definition,
-				binding:    binding,
+				Definition: definition,
+				Binding:    binding,
 			})
 		}
 	}
-	for definitionNamespacedName, definitionInfo := range c.definitionInfo {
+	policyDatas := c.definitions.Load().([]policyData)
+
+	authz := newCachingAuthorizer(c.authz)
+
+	for _, definitionInfo := range policyDatas {
+		// versionedAttributes will be set to non-nil inside of the loop, but
+		// is scoped outside of the param loop so we only convert once. We defer
+		// conversion so that it is only performed when we know a policy matches,
+		// saving the cost of converting non-matching requests.
+		var versionedAttr *admission.VersionedAttributes
+
 		definition := definitionInfo.lastReconciledValue
-		matches, matchKind, err := c.validatorCompiler.DefinitionMatches(a, o, definition)
+		matches, matchResource, matchKind, err := c.policyController.matcher.DefinitionMatches(a, o, definition)
 		if err != nil {
 			// Configuration error.
 			addConfigError(err, definition, nil)
@@ -262,17 +259,12 @@ func (c *celAdmissionController) Validate(
 			continue
 		}
 
-		dependentBindings := c.definitionsToBindings[definitionNamespacedName]
-		if len(dependentBindings) == 0 {
-			continue
-		}
-
-		for namespacedBindingName := range dependentBindings {
+		auditAnnotationCollector := newAuditAnnotationCollector()
+		for _, bindingInfo := range definitionInfo.bindings {
 			// If the key is inside dependentBindings, there is guaranteed to
 			// be a bindingInfo for it
-			bindingInfo := c.bindingInfos[namespacedBindingName]
 			binding := bindingInfo.lastReconciledValue
-			matches, err := c.validatorCompiler.BindingMatches(a, o, binding)
+			matches, err := c.policyController.matcher.BindingMatches(a, o, binding)
 			if err != nil {
 				// Configuration error.
 				addConfigError(err, definition, binding)
@@ -282,109 +274,131 @@ func (c *celAdmissionController) Validate(
 				continue
 			}
 
-			var param *unstructured.Unstructured
-
-			// If definition has paramKind, paramRef is required in binding.
-			// If definition has no paramKind, paramRef set in binding will be ignored.
-			paramKind := definition.Spec.ParamKind
-			paramRef := binding.Spec.ParamRef
-			if paramKind != nil && paramRef != nil {
-
-				// Find the params referred by the binding by looking its name up
-				// in our informer for its CRD
-				paramInfo, ok := c.paramsCRDControllers[*paramKind]
-				if !ok {
-					addConfigError(fmt.Errorf("paramKind kind `%v` not known",
-						paramKind.String()), definition, binding)
-					continue
-				}
-
-				// If the param informer for this admission policy has not yet
-				// had time to perform an initial listing, don't attempt to use
-				// it.
-				//!TOOD(alexzielenski): add a wait for a very short amount of
-				// time for the cache to sync
-				if !paramInfo.controller.HasSynced() {
-					addConfigError(fmt.Errorf("paramKind kind `%v` not yet synced to use for admission",
-						paramKind.String()), definition, binding)
-					continue
-				}
-
-				if len(paramRef.Namespace) == 0 {
-					param, err = paramInfo.controller.Informer().Get(paramRef.Name)
-				} else {
-					param, err = paramInfo.controller.Informer().Namespaced(paramRef.Namespace).Get(paramRef.Name)
-				}
-
-				if err != nil {
-					// Apply failure policy
-					addConfigError(err, definition, binding)
-
-					if k8serrors.IsInvalid(err) {
-						// Param mis-configured
-						// require to set paramRef.namespace for namespaced resource and unset paramRef.namespace for cluster scoped resource
-						continue
-					} else if k8serrors.IsNotFound(err) {
-						// Param not yet available. User may need to wait a bit
-						// before being able to use it for validation.
-						continue
-					}
-
-					// There was a bad internal error
-					utilruntime.HandleError(err)
-					continue
-				}
-			}
-
-			validator := bindingInfo.validator.Load()
-			if validator == nil {
-				// Compile policy definition using binding
-				newValidator := c.validatorCompiler.Compile(definition)
-				validator = &newValidator
-
-				bindingInfo.validator.Store(validator)
-			}
-
-			decisions, err := (*validator).Validate(a, o, param, matchKind)
+			params, err := c.collectParams(definition.Spec.ParamKind, definitionInfo.paramInfo, binding.Spec.ParamRef, a.GetNamespace())
 			if err != nil {
-				// runtime error. Apply failure policy
-				wrappedError := fmt.Errorf("failed to evaluate CEL expression: %w", err)
-				addConfigError(wrappedError, definition, binding)
+				addConfigError(err, definition, binding)
 				continue
+			} else if versionedAttr == nil && len(params) > 0 {
+				// As optimization versionedAttr creation is deferred until
+				// first use. Since > 0 params, we will validate
+				va, err := admission.NewVersionedAttributes(a, matchKind, o)
+				if err != nil {
+					wrappedErr := fmt.Errorf("failed to convert object version: %w", err)
+					addConfigError(wrappedErr, definition, binding)
+					continue
+				}
+				versionedAttr = va
 			}
 
-			for _, decision := range decisions {
-				switch decision.action {
-				case actionAdmit:
-					if decision.evaluation == evalError {
-						celmetrics.Metrics.ObserveAdmissionWithError(ctx, decision.elapsed, definition.Name, binding.Name, "active")
+			var validationResults []ValidateResult
+			var namespace *v1.Namespace
+			namespaceName := a.GetNamespace()
+
+			// Special case, the namespace object has the namespace of itself (maybe a bug).
+			// unset it if the incoming object is a namespace
+			if gvk := a.GetKind(); gvk.Kind == "Namespace" && gvk.Version == "v1" && gvk.Group == "" {
+				namespaceName = ""
+			}
+
+			// if it is cluster scoped, namespaceName will be empty
+			// Otherwise, get the Namespace resource.
+			if namespaceName != "" {
+				namespace, err = c.policyController.matcher.GetNamespace(namespaceName)
+				if err != nil {
+					return err
+				}
+			}
+
+			for _, param := range params {
+				var p runtime.Object = param
+				if p != nil && p.GetObjectKind().GroupVersionKind().Empty() {
+					// Make sure param has TypeMeta populated
+					// This is a simple hack to make sure typeMeta is
+					// available to CEL without making copies of objects, etc.
+					p = &wrappedParam{
+						TypeMeta: metav1.TypeMeta{
+							APIVersion: definition.Spec.ParamKind.APIVersion,
+							Kind:       definition.Spec.ParamKind.Kind,
+						},
+						nested: param,
+					}
+				}
+				validationResults = append(validationResults, bindingInfo.validator.Validate(ctx, matchResource, versionedAttr, p, namespace, celconfig.RuntimeCELCostBudget, authz))
+			}
+
+			for _, validationResult := range validationResults {
+				for i, decision := range validationResult.Decisions {
+					switch decision.Action {
+					case ActionAdmit:
+						if decision.Evaluation == EvalError {
+							celmetrics.Metrics.ObserveAdmissionWithError(ctx, decision.Elapsed, definition.Name, binding.Name, "active")
+						}
+					case ActionDeny:
+						for _, action := range binding.Spec.ValidationActions {
+							switch action {
+							case v1beta1.Deny:
+								deniedDecisions = append(deniedDecisions, policyDecisionWithMetadata{
+									Definition:     definition,
+									Binding:        binding,
+									PolicyDecision: decision,
+								})
+								celmetrics.Metrics.ObserveRejection(ctx, decision.Elapsed, definition.Name, binding.Name, "active")
+							case v1beta1.Audit:
+								c.publishValidationFailureAnnotation(binding, i, decision, versionedAttr)
+								celmetrics.Metrics.ObserveAudit(ctx, decision.Elapsed, definition.Name, binding.Name, "active")
+							case v1beta1.Warn:
+								warning.AddWarning(ctx, "", fmt.Sprintf("Validation failed for ValidatingAdmissionPolicy '%s' with binding '%s': %s", definition.Name, binding.Name, decision.Message))
+								celmetrics.Metrics.ObserveWarn(ctx, decision.Elapsed, definition.Name, binding.Name, "active")
+							}
+						}
+					default:
+						return fmt.Errorf("unrecognized evaluation decision '%s' for ValidatingAdmissionPolicyBinding '%s' with ValidatingAdmissionPolicy '%s'",
+							decision.Action, binding.Name, definition.Name)
+					}
+				}
+
+				for _, auditAnnotation := range validationResult.AuditAnnotations {
+					switch auditAnnotation.Action {
+					case AuditAnnotationActionPublish:
+						value := auditAnnotation.Value
+						if len(auditAnnotation.Value) > maxAuditAnnotationValueLength {
+							value = value[:maxAuditAnnotationValueLength]
+						}
+						auditAnnotationCollector.add(auditAnnotation.Key, value)
+					case AuditAnnotationActionError:
+						// When failurePolicy=fail, audit annotation errors result in deny
+						deniedDecisions = append(deniedDecisions, policyDecisionWithMetadata{
+							Definition: definition,
+							Binding:    binding,
+							PolicyDecision: PolicyDecision{
+								Action:     ActionDeny,
+								Evaluation: EvalError,
+								Message:    auditAnnotation.Error,
+								Elapsed:    auditAnnotation.Elapsed,
+							},
+						})
+						celmetrics.Metrics.ObserveRejection(ctx, auditAnnotation.Elapsed, definition.Name, binding.Name, "active")
+					case AuditAnnotationActionExclude: // skip it
+					default:
+						return fmt.Errorf("unsupported AuditAnnotation Action: %s", auditAnnotation.Action)
 					}
-				case actionDeny:
-					deniedDecisions = append(deniedDecisions, policyDecisionWithMetadata{
-						definition:     definition,
-						binding:        binding,
-						policyDecision: decision,
-					})
-					celmetrics.Metrics.ObserveRejection(ctx, decision.elapsed, definition.Name, binding.Name, "active")
-				default:
-					return fmt.Errorf("unrecognized evaluation decision '%s' for ValidatingAdmissionPolicyBinding '%s' with ValidatingAdmissionPolicy '%s'",
-						decision.action, binding.Name, definition.Name)
 				}
 			}
 		}
+		auditAnnotationCollector.publish(definition.Name, a)
 	}
 
 	if len(deniedDecisions) > 0 {
 		// TODO: refactor admission.NewForbidden so the name extraction is reusable but the code/reason is customizable
 		var message string
 		deniedDecision := deniedDecisions[0]
-		if deniedDecision.binding != nil {
-			message = fmt.Sprintf("ValidatingAdmissionPolicy '%s' with binding '%s' denied request: %s", deniedDecision.definition.Name, deniedDecision.binding.Name, deniedDecision.message)
+		if deniedDecision.Binding != nil {
+			message = fmt.Sprintf("ValidatingAdmissionPolicy '%s' with binding '%s' denied request: %s", deniedDecision.Definition.Name, deniedDecision.Binding.Name, deniedDecision.Message)
 		} else {
-			message = fmt.Sprintf("ValidatingAdmissionPolicy '%s' denied request: %s", deniedDecision.definition.Name, deniedDecision.message)
+			message = fmt.Sprintf("ValidatingAdmissionPolicy '%s' denied request: %s", deniedDecision.Definition.Name, deniedDecision.Message)
 		}
 		err := admission.NewForbidden(a, errors.New(message)).(*k8serrors.StatusError)
-		reason := deniedDecision.reason
+		reason := deniedDecision.Reason
 		if len(reason) == 0 {
 			reason = metav1.StatusReasonInvalid
 		}
@@ -396,11 +410,240 @@ func (c *celAdmissionController) Validate(
 	return nil
 }
 
+// Returns objects to use to evaluate the policy
+func (c *celAdmissionController) collectParams(
+	paramKind *v1beta1.ParamKind,
+	info paramInfo,
+	paramRef *v1beta1.ParamRef,
+	namespace string,
+) ([]runtime.Object, error) {
+	// If definition has paramKind, paramRef is required in binding.
+	// If definition has no paramKind, paramRef set in binding will be ignored.
+	var params []runtime.Object
+	var paramStore generic.NamespacedLister[runtime.Object]
+
+	// Make sure the param kind is ready to use
+	if paramKind != nil && paramRef != nil {
+		if info.controller == nil {
+			return nil, fmt.Errorf("paramKind kind `%v` not known",
+				paramKind.String())
+		}
+
+		// Set up cluster-scoped, or namespaced access to the params
+		// "default" if not provided, and paramKind is namespaced
+		paramStore = info.controller.Informer()
+		if info.scope.Name() == meta.RESTScopeNameNamespace {
+			paramsNamespace := namespace
+			if len(paramRef.Namespace) > 0 {
+				paramsNamespace = paramRef.Namespace
+			} else if len(paramsNamespace) == 0 {
+				// You must supply namespace if your matcher can possibly
+				// match a cluster-scoped resource
+				return nil, fmt.Errorf("cannot use namespaced paramRef in policy binding that matches cluster-scoped resources")
+			}
+
+			paramStore = info.controller.Informer().Namespaced(paramsNamespace)
+		}
+
+		// If the param informer for this admission policy has not yet
+		// had time to perform an initial listing, don't attempt to use
+		// it.
+		timeoutCtx, cancel := context.WithTimeout(c.policyController.context, 1*time.Second)
+		defer cancel()
+
+		if !cache.WaitForCacheSync(timeoutCtx.Done(), info.controller.HasSynced) {
+			return nil, fmt.Errorf("paramKind kind `%v` not yet synced to use for admission",
+				paramKind.String())
+		}
+	}
+
+	// Find params to use with policy
+	switch {
+	case paramKind == nil:
+		// ParamKind is unset. Ignore any globalParamRef or namespaceParamRef
+		// setting.
+		return []runtime.Object{nil}, nil
+	case paramRef == nil:
+		// Policy ParamKind is set, but binding does not use it.
+		// Validate with nil params
+		return []runtime.Object{nil}, nil
+	case len(paramRef.Namespace) > 0 && info.scope.Name() == meta.RESTScopeRoot.Name():
+		// Not allowed to set namespace for cluster-scoped param
+		return nil, fmt.Errorf("paramRef.namespace must not be provided for a cluster-scoped `paramKind`")
+
+	case len(paramRef.Name) > 0:
+		if paramRef.Selector != nil {
+			// This should be validated, but just in case.
+			return nil, fmt.Errorf("paramRef.name and paramRef.selector are mutually exclusive")
+		}
+
+		switch param, err := paramStore.Get(paramRef.Name); {
+		case err == nil:
+			params = []runtime.Object{param}
+		case k8serrors.IsNotFound(err):
+			// Param not yet available. User may need to wait a bit
+			// before being able to use it for validation.
+			//
+			// Set params to nil to prepare for not found action
+			params = nil
+		case k8serrors.IsInvalid(err):
+			// Param mis-configured
+			// require to set namespace for namespaced resource
+			// and unset namespace for cluster scoped resource
+			return nil, err
+		default:
+			// Internal error
+			utilruntime.HandleError(err)
+			return nil, err
+		}
+	case paramRef.Selector != nil:
+		// Select everything by default if empty name and selector
+		selector, err := metav1.LabelSelectorAsSelector(paramRef.Selector)
+		if err != nil {
+			// Cannot parse label selector: configuration error
+			return nil, err
+
+		}
+
+		paramList, err := paramStore.List(selector)
+		if err != nil {
+			// There was a bad internal error
+			utilruntime.HandleError(err)
+			return nil, err
+		}
+
+		// Successfully grabbed params
+		params = paramList
+	default:
+		// Should be unreachable due to validation
+		return nil, fmt.Errorf("one of name or selector must be provided")
+	}
+
+	// Apply fail action for params not found case
+	if len(params) == 0 && paramRef.ParameterNotFoundAction != nil && *paramRef.ParameterNotFoundAction == v1beta1.DenyAction {
+		return nil, errors.New("no params found for policy binding with `Deny` parameterNotFoundAction")
+	}
+
+	return params, nil
+}
+
+func (c *celAdmissionController) publishValidationFailureAnnotation(binding *v1beta1.ValidatingAdmissionPolicyBinding, expressionIndex int, decision PolicyDecision, attributes admission.Attributes) {
+	key := "validation.policy.admission.k8s.io/validation_failure"
+	// Marshal to a list of failures since, in the future, we may need to support multiple failures
+	valueJson, err := utiljson.Marshal([]validationFailureValue{{
+		ExpressionIndex:   expressionIndex,
+		Message:           decision.Message,
+		ValidationActions: binding.Spec.ValidationActions,
+		Binding:           binding.Name,
+		Policy:            binding.Spec.PolicyName,
+	}})
+	if err != nil {
+		klog.Warningf("Failed to set admission audit annotation %s for ValidatingAdmissionPolicy %s and ValidatingAdmissionPolicyBinding %s: %v", key, binding.Spec.PolicyName, binding.Name, err)
+	}
+	value := string(valueJson)
+	if err := attributes.AddAnnotation(key, value); err != nil {
+		klog.Warningf("Failed to set admission audit annotation %s to %s for ValidatingAdmissionPolicy %s and ValidatingAdmissionPolicyBinding %s: %v", key, value, binding.Spec.PolicyName, binding.Name, err)
+	}
+}
+
 func (c *celAdmissionController) HasSynced() bool {
-	return c.policyBindingController.HasSynced() &&
-		c.policyDefinitionsController.HasSynced()
+	return c.policyController.HasSynced() && c.definitions.Load() != nil
 }
 
 func (c *celAdmissionController) ValidateInitialization() error {
-	return c.validatorCompiler.ValidateInitialization()
+	return c.policyController.matcher.ValidateInitialization()
+}
+
+func (c *celAdmissionController) refreshPolicies() {
+	c.definitions.Store(c.policyController.latestPolicyData())
+}
+
+// validationFailureValue defines the JSON format of a "validation.policy.admission.k8s.io/validation_failure" audit
+// annotation value.
+type validationFailureValue struct {
+	Message           string                     `json:"message"`
+	Policy            string                     `json:"policy"`
+	Binding           string                     `json:"binding"`
+	ExpressionIndex   int                        `json:"expressionIndex"`
+	ValidationActions []v1beta1.ValidationAction `json:"validationActions"`
+}
+
+type auditAnnotationCollector struct {
+	annotations map[string][]string
+}
+
+func newAuditAnnotationCollector() auditAnnotationCollector {
+	return auditAnnotationCollector{annotations: map[string][]string{}}
+}
+
+func (a auditAnnotationCollector) add(key, value string) {
+	// If multiple bindings produces the exact same key and value for an audit annotation,
+	// ignore the duplicates.
+	for _, v := range a.annotations[key] {
+		if v == value {
+			return
+		}
+	}
+	a.annotations[key] = append(a.annotations[key], value)
+}
+
+func (a auditAnnotationCollector) publish(policyName string, attributes admission.Attributes) {
+	for key, bindingAnnotations := range a.annotations {
+		var value string
+		if len(bindingAnnotations) == 1 {
+			value = bindingAnnotations[0]
+		} else {
+			// Multiple distinct values can exist when binding params are used in the valueExpression of an auditAnnotation.
+			// When this happens, the values are concatenated into a comma-separated list.
+			value = strings.Join(bindingAnnotations, ", ")
+		}
+		if err := attributes.AddAnnotation(policyName+"/"+key, value); err != nil {
+			klog.Warningf("Failed to set admission audit annotation %s to %s for ValidatingAdmissionPolicy %s: %v", key, value, policyName, err)
+		}
+	}
+}
+
+// A workaround to fact that native types do not have TypeMeta populated, which
+// is needed for CEL expressions to be able to access the value.
+type wrappedParam struct {
+	metav1.TypeMeta
+	nested runtime.Object
+}
+
+func (w *wrappedParam) MarshalJSON() ([]byte, error) {
+	return nil, errors.New("MarshalJSON unimplemented for wrappedParam")
+}
+
+func (w *wrappedParam) UnmarshalJSON(data []byte) error {
+	return errors.New("UnmarshalJSON unimplemented for wrappedParam")
+}
+
+func (w *wrappedParam) ToUnstructured() interface{} {
+	res, err := runtime.DefaultUnstructuredConverter.ToUnstructured(w.nested)
+
+	if err != nil {
+		return nil
+	}
+
+	metaRes, err := runtime.DefaultUnstructuredConverter.ToUnstructured(&w.TypeMeta)
+	if err != nil {
+		return nil
+	}
+
+	for k, v := range metaRes {
+		res[k] = v
+	}
+
+	return res
+}
+
+func (w *wrappedParam) DeepCopyObject() runtime.Object {
+	return &wrappedParam{
+		TypeMeta: w.TypeMeta,
+		nested:   w.nested.DeepCopyObject(),
+	}
+}
+
+func (w *wrappedParam) GetObjectKind() schema.ObjectKind {
+	return w
 }

vendor/k8s.io/apiserver/pkg/admission/plugin/validatingadmissionpolicy/controller_reconcile.go

@@ -19,22 +19,156 @@ package validatingadmissionpolicy
 import (
 	"context"
 	"fmt"
+	"sync"
 	"time"
 
-	"k8s.io/api/admissionregistration/v1alpha1"
+	v1 "k8s.io/api/admissionregistration/v1"
+	"k8s.io/api/admissionregistration/v1beta1"
 	corev1 "k8s.io/api/core/v1"
-	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
+	apiequality "k8s.io/apimachinery/pkg/api/equality"
+	"k8s.io/apimachinery/pkg/api/meta"
+	"k8s.io/apimachinery/pkg/runtime"
 	"k8s.io/apimachinery/pkg/runtime/schema"
+	utilruntime "k8s.io/apimachinery/pkg/util/runtime"
 	"k8s.io/apimachinery/pkg/util/sets"
 	celmetrics "k8s.io/apiserver/pkg/admission/cel"
+	"k8s.io/apiserver/pkg/admission/plugin/cel"
 	"k8s.io/apiserver/pkg/admission/plugin/validatingadmissionpolicy/internal/generic"
+	"k8s.io/apiserver/pkg/admission/plugin/webhook/matchconditions"
+	"k8s.io/apiserver/pkg/cel/environment"
+	"k8s.io/client-go/dynamic"
 	"k8s.io/client-go/dynamic/dynamicinformer"
+	"k8s.io/client-go/informers"
+	"k8s.io/client-go/kubernetes"
 	"k8s.io/client-go/tools/cache"
 )
 
-func (c *celAdmissionController) reconcilePolicyDefinition(namespace, name string, definition *v1alpha1.ValidatingAdmissionPolicy) error {
+type policyController struct {
+	once                        sync.Once
+	context                     context.Context
+	dynamicClient               dynamic.Interface
+	informerFactory             informers.SharedInformerFactory
+	restMapper                  meta.RESTMapper
+	policyDefinitionsController generic.Controller[*v1beta1.ValidatingAdmissionPolicy]
+	policyBindingController     generic.Controller[*v1beta1.ValidatingAdmissionPolicyBinding]
+
+	// Provided to the policy's Compile function as an injected dependency to
+	// assist with compiling its expressions to CEL
+	// pass nil to create filter compiler in demand
+	filterCompiler cel.FilterCompiler
+
+	matcher Matcher
+
+	newValidator
+
+	client kubernetes.Interface
+	// Lock which protects
+	// All Below fields
+	// All above fields should be assumed constant
+	mutex sync.RWMutex
+
+	cachedPolicies []policyData
+
+	// controller and metadata
+	paramsCRDControllers map[v1beta1.ParamKind]*paramInfo
+
+	// Index for each definition namespace/name, contains all binding
+	// namespace/names known to exist for that definition
+	definitionInfo map[namespacedName]*definitionInfo
+
+	// Index for each bindings namespace/name. Contains compiled templates
+	// for the binding depending on the policy/param combination.
+	bindingInfos map[namespacedName]*bindingInfo
+
+	// Map from namespace/name of a definition to a set of namespace/name
+	// of bindings which depend on it.
+	// All keys must have at least one dependent binding
+	// All binding names MUST exist as a key bindingInfos
+	definitionsToBindings map[namespacedName]sets.Set[namespacedName]
+}
+
+type newValidator func(validationFilter cel.Filter, celMatcher matchconditions.Matcher, auditAnnotationFilter, messageFilter cel.Filter, failurePolicy *v1.FailurePolicyType) Validator
+
+func newPolicyController(
+	restMapper meta.RESTMapper,
+	client kubernetes.Interface,
+	dynamicClient dynamic.Interface,
+	informerFactory informers.SharedInformerFactory,
+	filterCompiler cel.FilterCompiler,
+	matcher Matcher,
+	policiesInformer generic.Informer[*v1beta1.ValidatingAdmissionPolicy],
+	bindingsInformer generic.Informer[*v1beta1.ValidatingAdmissionPolicyBinding],
+) *policyController {
+	res := &policyController{}
+	*res = policyController{
+		filterCompiler:        filterCompiler,
+		definitionInfo:        make(map[namespacedName]*definitionInfo),
+		bindingInfos:          make(map[namespacedName]*bindingInfo),
+		paramsCRDControllers:  make(map[v1beta1.ParamKind]*paramInfo),
+		definitionsToBindings: make(map[namespacedName]sets.Set[namespacedName]),
+		matcher:               matcher,
+		newValidator:          NewValidator,
+		policyDefinitionsController: generic.NewController(
+			policiesInformer,
+			res.reconcilePolicyDefinition,
+			generic.ControllerOptions{
+				Workers: 1,
+				Name:    "cel-policy-definitions",
+			},
+		),
+		policyBindingController: generic.NewController(
+			bindingsInformer,
+			res.reconcilePolicyBinding,
+			generic.ControllerOptions{
+				Workers: 1,
+				Name:    "cel-policy-bindings",
+			},
+		),
+		restMapper:      restMapper,
+		dynamicClient:   dynamicClient,
+		informerFactory: informerFactory,
+		client:          client,
+	}
+	return res
+}
+
+func (c *policyController) Run(ctx context.Context) {
+	// Only support being run once
+	c.once.Do(func() {
+		c.context = ctx
+
+		wg := sync.WaitGroup{}
+
+		wg.Add(1)
+		go func() {
+			defer wg.Done()
+			c.policyDefinitionsController.Run(ctx)
+		}()
+
+		wg.Add(1)
+		go func() {
+			defer wg.Done()
+			c.policyBindingController.Run(ctx)
+		}()
+
+		<-ctx.Done()
+		wg.Wait()
+	})
+}
+
+func (c *policyController) HasSynced() bool {
+	return c.policyDefinitionsController.HasSynced() && c.policyBindingController.HasSynced()
+}
+
+func (c *policyController) reconcilePolicyDefinition(namespace, name string, definition *v1beta1.ValidatingAdmissionPolicy) error {
 	c.mutex.Lock()
 	defer c.mutex.Unlock()
+	err := c.reconcilePolicyDefinitionSpec(namespace, name, definition)
+	return err
+}
+
+func (c *policyController) reconcilePolicyDefinitionSpec(namespace, name string, definition *v1beta1.ValidatingAdmissionPolicy) error {
+	c.cachedPolicies = nil // invalidate cachedPolicies
 
 	// Namespace for policydefinition is empty.
 	nn := getNamespaceName(namespace, name)
@@ -46,7 +180,14 @@ func (c *celAdmissionController) reconcilePolicyDefinition(namespace, name strin
 		celmetrics.Metrics.ObserveDefinition(context.TODO(), "active", "deny")
 	}
 
-	var paramSource *v1alpha1.ParamKind
+	// Skip reconcile if the spec of the definition is unchanged and had a
+	// successful previous sync
+	if info.configurationError == nil && info.lastReconciledValue != nil && definition != nil &&
+		apiequality.Semantic.DeepEqual(info.lastReconciledValue.Spec, definition.Spec) {
+		return nil
+	}
+
+	var paramSource *v1beta1.ParamKind
 	if definition != nil {
 		paramSource = definition.Spec.ParamKind
 	}
@@ -75,7 +216,7 @@ func (c *celAdmissionController) reconcilePolicyDefinition(namespace, name strin
 	// definition has changed.
 	for key := range c.definitionsToBindings[nn] {
 		bindingInfo := c.bindingInfos[key]
-		bindingInfo.validator.Store(nil)
+		bindingInfo.validator = nil
 		c.bindingInfos[key] = bindingInfo
 	}
 
@@ -92,7 +233,6 @@ func (c *celAdmissionController) reconcilePolicyDefinition(namespace, name strin
 		// Skip setting up controller for empty param type
 		return nil
 	}
-
 	// find GVR for params
 	// Parse param source into a GVK
 
@@ -119,46 +259,83 @@ func (c *celAdmissionController) reconcilePolicyDefinition(namespace, name strin
 		return info.configurationError
 	}
 
-	// Start watching the param CRD
-	if _, ok := c.paramsCRDControllers[*paramSource]; !ok {
-		instanceContext, instanceCancel := context.WithCancel(c.runningContext)
-
-		// Watch for new instances of this policy
-		informer := dynamicinformer.NewFilteredDynamicInformer(
-			c.dynamicClient,
-			paramsGVR.Resource,
-			corev1.NamespaceAll,
-			30*time.Second,
-			cache.Indexers{cache.NamespaceIndex: cache.MetaNamespaceIndexFunc},
-			nil,
-		)
-
-		controller := generic.NewController(
-			generic.NewInformer[*unstructured.Unstructured](informer.Informer()),
-			c.reconcileParams,
-			generic.ControllerOptions{
-				Workers: 1,
-				Name:    paramSource.String() + "-controller",
-			},
-		)
-
-		c.paramsCRDControllers[*paramSource] = &paramInfo{
-			controller:           controller,
-			stop:                 instanceCancel,
-			dependentDefinitions: sets.New(nn),
-		}
-
-		go informer.Informer().Run(instanceContext.Done())
-		go controller.Run(instanceContext)
-	}
+	paramInfo := c.ensureParamInfo(paramSource, paramsGVR)
+	paramInfo.dependentDefinitions.Insert(nn)
 
 	return nil
 }
 
-func (c *celAdmissionController) reconcilePolicyBinding(namespace, name string, binding *v1alpha1.ValidatingAdmissionPolicyBinding) error {
+// Ensures that there is an informer started for the given GVK to be used as a
+// param
+func (c *policyController) ensureParamInfo(paramSource *v1beta1.ParamKind, mapping *meta.RESTMapping) *paramInfo {
+	if info, ok := c.paramsCRDControllers[*paramSource]; ok {
+		return info
+	}
+
+	// We are not watching this param. Start an informer for it.
+	instanceContext, instanceCancel := context.WithCancel(c.context)
+
+	var informer cache.SharedIndexInformer
+
+	// Try to see if our provided informer factory has an informer for this type.
+	// We assume the informer is already started, and starts all types associated
+	// with it.
+	if genericInformer, err := c.informerFactory.ForResource(mapping.Resource); err == nil {
+		informer = genericInformer.Informer()
+
+		// Ensure the informer is started
+		// Use policyController's context rather than the instance context.
+		// PolicyController context is expected to last until app shutdown
+		// This is due to behavior of informerFactory which would cause the
+		// informer to stop running once the context is cancelled, and
+		// never started again.
+		c.informerFactory.Start(c.context.Done())
+	} else {
+		// Dynamic JSON informer fallback.
+		// Cannot use shared dynamic informer since it would be impossible
+		// to clean CRD informers properly with multiple dependents
+		// (cannot start ahead of time, and cannot track dependencies via stopCh)
+		informer = dynamicinformer.NewFilteredDynamicInformer(
+			c.dynamicClient,
+			mapping.Resource,
+			corev1.NamespaceAll,
+			// Use same interval as is used for k8s typed sharedInformerFactory
+			// https://github.com/kubernetes/kubernetes/blob/7e0923899fed622efbc8679cca6b000d43633e38/cmd/kube-apiserver/app/server.go#L430
+			10*time.Minute,
+			cache.Indexers{cache.NamespaceIndex: cache.MetaNamespaceIndexFunc},
+			nil,
+		).Informer()
+		go informer.Run(instanceContext.Done())
+	}
+
+	controller := generic.NewController(
+		generic.NewInformer[runtime.Object](informer),
+		c.reconcileParams,
+		generic.ControllerOptions{
+			Workers: 1,
+			Name:    paramSource.String() + "-controller",
+		},
+	)
+
+	ret := &paramInfo{
+		controller:           controller,
+		stop:                 instanceCancel,
+		scope:                mapping.Scope,
+		dependentDefinitions: sets.New[namespacedName](),
+	}
+	c.paramsCRDControllers[*paramSource] = ret
+
+	go controller.Run(instanceContext)
+	return ret
+
+}
+
+func (c *policyController) reconcilePolicyBinding(namespace, name string, binding *v1beta1.ValidatingAdmissionPolicyBinding) error {
 	c.mutex.Lock()
 	defer c.mutex.Unlock()
 
+	c.cachedPolicies = nil // invalidate cachedPolicies
+
 	// Namespace for PolicyBinding is empty. In the future a namespaced binding
 	// may be added
 	// https://github.com/kubernetes/enhancements/blob/bf5c3c81ea2081d60c1dc7c832faa98479e06209/keps/sig-api-machinery/3488-cel-admission-control/README.md?plain=1#L1042
@@ -169,6 +346,12 @@ func (c *celAdmissionController) reconcilePolicyBinding(namespace, name string,
 		c.bindingInfos[nn] = info
 	}
 
+	// Skip if the spec of the binding is unchanged.
+	if info.lastReconciledValue != nil && binding != nil &&
+		apiequality.Semantic.DeepEqual(info.lastReconciledValue.Spec, binding.Spec) {
+		return nil
+	}
+
 	var oldNamespacedDefinitionName namespacedName
 	if info.lastReconciledValue != nil {
 		// All validating policies are cluster-scoped so have empty namespace
@@ -208,12 +391,12 @@ func (c *celAdmissionController) reconcilePolicyBinding(namespace, name string,
 	}
 
 	// Remove compiled template for old binding
-	info.validator.Store(nil)
+	info.validator = nil
 	info.lastReconciledValue = binding
 	return nil
 }
 
-func (c *celAdmissionController) reconcileParams(namespace, name string, params *unstructured.Unstructured) error {
+func (c *policyController) reconcileParams(namespace, name string, params runtime.Object) error {
 	// Do nothing.
 	// When we add informational type checking we will need to compile in the
 	// reconcile loops instead of lazily so we can add compiler errors / type
@@ -221,6 +404,145 @@ func (c *celAdmissionController) reconcileParams(namespace, name string, params
 	return nil
 }
 
+// Fetches the latest set of policy data or recalculates it if it has changed
+// since it was last fetched
+func (c *policyController) latestPolicyData() []policyData {
+	existing := func() []policyData {
+		c.mutex.RLock()
+		defer c.mutex.RUnlock()
+
+		return c.cachedPolicies
+	}()
+
+	if existing != nil {
+		return existing
+	}
+
+	c.mutex.Lock()
+	defer c.mutex.Unlock()
+
+	var res []policyData
+	for definitionNN, definitionInfo := range c.definitionInfo {
+		var bindingInfos []bindingInfo
+		for bindingNN := range c.definitionsToBindings[definitionNN] {
+			bindingInfo := c.bindingInfos[bindingNN]
+			if bindingInfo.validator == nil && definitionInfo.configurationError == nil {
+				hasParam := false
+				if definitionInfo.lastReconciledValue.Spec.ParamKind != nil {
+					hasParam = true
+				}
+				optionalVars := cel.OptionalVariableDeclarations{HasParams: hasParam, HasAuthorizer: true}
+				expressionOptionalVars := cel.OptionalVariableDeclarations{HasParams: hasParam, HasAuthorizer: false}
+				failurePolicy := convertv1beta1FailurePolicyTypeTov1FailurePolicyType(definitionInfo.lastReconciledValue.Spec.FailurePolicy)
+				var matcher matchconditions.Matcher = nil
+				matchConditions := definitionInfo.lastReconciledValue.Spec.MatchConditions
+
+				filterCompiler := c.filterCompiler
+				if filterCompiler == nil {
+					compositedCompiler, err := cel.NewCompositedCompiler(environment.MustBaseEnvSet(environment.DefaultCompatibilityVersion()))
+					if err == nil {
+						filterCompiler = compositedCompiler
+						compositedCompiler.CompileAndStoreVariables(convertv1beta1Variables(definitionInfo.lastReconciledValue.Spec.Variables), optionalVars, environment.StoredExpressions)
+					} else {
+						utilruntime.HandleError(err)
+					}
+				}
+				if len(matchConditions) > 0 {
+					matchExpressionAccessors := make([]cel.ExpressionAccessor, len(matchConditions))
+					for i := range matchConditions {
+						matchExpressionAccessors[i] = (*matchconditions.MatchCondition)(&matchConditions[i])
+					}
+					matcher = matchconditions.NewMatcher(filterCompiler.Compile(matchExpressionAccessors, optionalVars, environment.StoredExpressions), failurePolicy, "policy", "validate", definitionInfo.lastReconciledValue.Name)
+				}
+				bindingInfo.validator = c.newValidator(
+					filterCompiler.Compile(convertv1beta1Validations(definitionInfo.lastReconciledValue.Spec.Validations), optionalVars, environment.StoredExpressions),
+					matcher,
+					filterCompiler.Compile(convertv1beta1AuditAnnotations(definitionInfo.lastReconciledValue.Spec.AuditAnnotations), optionalVars, environment.StoredExpressions),
+					filterCompiler.Compile(convertv1beta1MessageExpressions(definitionInfo.lastReconciledValue.Spec.Validations), expressionOptionalVars, environment.StoredExpressions),
+					failurePolicy,
+				)
+			}
+			bindingInfos = append(bindingInfos, *bindingInfo)
+		}
+
+		var pInfo paramInfo
+		if paramKind := definitionInfo.lastReconciledValue.Spec.ParamKind; paramKind != nil {
+			if info, ok := c.paramsCRDControllers[*paramKind]; ok {
+				pInfo = *info
+			}
+		}
+
+		res = append(res, policyData{
+			definitionInfo: *definitionInfo,
+			paramInfo:      pInfo,
+			bindings:       bindingInfos,
+		})
+	}
+
+	c.cachedPolicies = res
+	return res
+}
+
+func convertv1beta1FailurePolicyTypeTov1FailurePolicyType(policyType *v1beta1.FailurePolicyType) *v1.FailurePolicyType {
+	if policyType == nil {
+		return nil
+	}
+
+	var v1FailPolicy v1.FailurePolicyType
+	if *policyType == v1beta1.Fail {
+		v1FailPolicy = v1.Fail
+	} else if *policyType == v1beta1.Ignore {
+		v1FailPolicy = v1.Ignore
+	}
+	return &v1FailPolicy
+}
+
+func convertv1beta1Validations(inputValidations []v1beta1.Validation) []cel.ExpressionAccessor {
+	celExpressionAccessor := make([]cel.ExpressionAccessor, len(inputValidations))
+	for i, validation := range inputValidations {
+		validation := ValidationCondition{
+			Expression: validation.Expression,
+			Message:    validation.Message,
+			Reason:     validation.Reason,
+		}
+		celExpressionAccessor[i] = &validation
+	}
+	return celExpressionAccessor
+}
+
+func convertv1beta1MessageExpressions(inputValidations []v1beta1.Validation) []cel.ExpressionAccessor {
+	celExpressionAccessor := make([]cel.ExpressionAccessor, len(inputValidations))
+	for i, validation := range inputValidations {
+		if validation.MessageExpression != "" {
+			condition := MessageExpressionCondition{
+				MessageExpression: validation.MessageExpression,
+			}
+			celExpressionAccessor[i] = &condition
+		}
+	}
+	return celExpressionAccessor
+}
+
+func convertv1beta1AuditAnnotations(inputValidations []v1beta1.AuditAnnotation) []cel.ExpressionAccessor {
+	celExpressionAccessor := make([]cel.ExpressionAccessor, len(inputValidations))
+	for i, validation := range inputValidations {
+		validation := AuditAnnotationCondition{
+			Key:             validation.Key,
+			ValueExpression: validation.ValueExpression,
+		}
+		celExpressionAccessor[i] = &validation
+	}
+	return celExpressionAccessor
+}
+
+func convertv1beta1Variables(variables []v1beta1.Variable) []cel.NamedExpressionAccessor {
+	namedExpressions := make([]cel.NamedExpressionAccessor, len(variables))
+	for i, variable := range variables {
+		namedExpressions[i] = &Variable{Name: variable.Name, Expression: variable.Expression}
+	}
+	return namedExpressions
+}
+
 func getNamespaceName(namespace, name string) namespacedName {
 	return namespacedName{
 		namespace: namespace,

vendor/k8s.io/apiserver/pkg/admission/plugin/validatingadmissionpolicy/initializer.go

@@ -18,6 +18,7 @@ package validatingadmissionpolicy
 
 import (
 	"context"
+
 	"k8s.io/apiserver/pkg/admission"
 )
 

vendor/k8s.io/apiserver/pkg/admission/plugin/validatingadmissionpolicy/interface.go

@@ -17,34 +17,97 @@ limitations under the License.
 package validatingadmissionpolicy
 
 import (
-	"k8s.io/api/admissionregistration/v1alpha1"
+	"context"
+
+	celgo "github.com/google/cel-go/cel"
+
+	"k8s.io/api/admissionregistration/v1beta1"
+	corev1 "k8s.io/api/core/v1"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/runtime"
 	"k8s.io/apimachinery/pkg/runtime/schema"
 	"k8s.io/apiserver/pkg/admission"
+	"k8s.io/apiserver/pkg/admission/plugin/cel"
+	"k8s.io/apiserver/pkg/authorization/authorizer"
 )
 
-// Validator defines the func used to validate the cel expressions
-// matchKind provides the GroupVersionKind that the object should be
-// validated by CEL expressions as.
-type Validator interface {
-	Validate(a admission.Attributes, o admission.ObjectInterfaces, versionedParams runtime.Object, matchKind schema.GroupVersionKind) ([]policyDecision, error)
+var _ cel.ExpressionAccessor = &ValidationCondition{}
+
+// ValidationCondition contains the inputs needed to compile, evaluate and validate a cel expression
+type ValidationCondition struct {
+	Expression string
+	Message    string
+	Reason     *metav1.StatusReason
 }
 
-// ValidatorCompiler is Dependency Injected into the PolicyDefinition's `Compile`
-// function to assist with converting types and values to/from CEL-typed values.
-type ValidatorCompiler interface {
+func (v *ValidationCondition) GetExpression() string {
+	return v.Expression
+}
+
+func (v *ValidationCondition) ReturnTypes() []*celgo.Type {
+	return []*celgo.Type{celgo.BoolType}
+}
+
+// AuditAnnotationCondition contains the inputs needed to compile, evaluate and publish a cel audit annotation
+type AuditAnnotationCondition struct {
+	Key             string
+	ValueExpression string
+}
+
+func (v *AuditAnnotationCondition) GetExpression() string {
+	return v.ValueExpression
+}
+
+func (v *AuditAnnotationCondition) ReturnTypes() []*celgo.Type {
+	return []*celgo.Type{celgo.StringType, celgo.NullType}
+}
+
+// Variable is a named expression for composition.
+type Variable struct {
+	Name       string
+	Expression string
+}
+
+func (v *Variable) GetExpression() string {
+	return v.Expression
+}
+
+func (v *Variable) ReturnTypes() []*celgo.Type {
+	return []*celgo.Type{celgo.AnyType, celgo.DynType}
+}
+
+func (v *Variable) GetName() string {
+	return v.Name
+}
+
+// Matcher is used for matching ValidatingAdmissionPolicy and ValidatingAdmissionPolicyBinding to attributes
+type Matcher interface {
 	admission.InitializationValidator
 
-	// Matches says whether this policy definition matches the provided admission
+	// DefinitionMatches says whether this policy definition matches the provided admission
 	// resource request
-	DefinitionMatches(a admission.Attributes, o admission.ObjectInterfaces, definition *v1alpha1.ValidatingAdmissionPolicy) (bool, schema.GroupVersionKind, error)
+	DefinitionMatches(a admission.Attributes, o admission.ObjectInterfaces, definition *v1beta1.ValidatingAdmissionPolicy) (bool, schema.GroupVersionResource, schema.GroupVersionKind, error)
 
-	// Matches says whether this policy definition matches the provided admission
+	// BindingMatches says whether this policy definition matches the provided admission
 	// resource request
-	BindingMatches(a admission.Attributes, o admission.ObjectInterfaces, definition *v1alpha1.ValidatingAdmissionPolicyBinding) (bool, error)
+	BindingMatches(a admission.Attributes, o admission.ObjectInterfaces, definition *v1beta1.ValidatingAdmissionPolicyBinding) (bool, error)
 
-	// Compile is used for the cel expression compilation
-	Compile(
-		policy *v1alpha1.ValidatingAdmissionPolicy,
-	) Validator
+	// GetNamespace retrieves the Namespace resource by the given name. The name may be empty, in which case
+	// GetNamespace must return nil, nil
+	GetNamespace(name string) (*corev1.Namespace, error)
+}
+
+// ValidateResult defines the result of a Validator.Validate operation.
+type ValidateResult struct {
+	// Decisions specifies the outcome of the validation as well as the details about the decision.
+	Decisions []PolicyDecision
+	// AuditAnnotations specifies the audit annotations that should be recorded for the validation.
+	AuditAnnotations []PolicyAuditAnnotation
+}
+
+// Validator is contains logic for converting ValidationEvaluation to PolicyDecisions
+type Validator interface {
+	// Validate is used to take cel evaluations and convert into decisions
+	// runtimeCELCostBudget was added for testing purpose only. Callers should always use const RuntimeCELCostBudget from k8s.io/apiserver/pkg/apis/cel/config.go as input.
+	Validate(ctx context.Context, matchedResource schema.GroupVersionResource, versionedAttr *admission.VersionedAttributes, versionedParams runtime.Object, namespace *corev1.Namespace, runtimeCELCostBudget int64, authz authorizer.Authorizer) ValidateResult
 }

vendor/k8s.io/apiserver/pkg/admission/plugin/validatingadmissionpolicy/internal/generic/controller.go

@@ -21,6 +21,7 @@ import (
 	"errors"
 	"fmt"
 	"sync"
+	"sync/atomic"
 	"time"
 
 	kerrors "k8s.io/apimachinery/pkg/api/errors"
@@ -30,6 +31,7 @@ import (
 
 	"k8s.io/apimachinery/pkg/util/wait"
 	"k8s.io/client-go/tools/cache"
+	"k8s.io/client-go/tools/cache/synctrack"
 	"k8s.io/client-go/util/workqueue"
 	"k8s.io/klog/v2"
 )
@@ -45,6 +47,11 @@ type controller[T runtime.Object] struct {
 	reconciler func(namespace, name string, newObj T) error
 
 	options ControllerOptions
+
+	// must hold a func() bool or nil
+	notificationsDelivered atomic.Value
+
+	hasProcessed synctrack.AsyncTracker[string]
 }
 
 type ControllerOptions struct {
@@ -69,12 +76,20 @@ func NewController[T runtime.Object](
 		options.Name = fmt.Sprintf("%T-controller", *new(T))
 	}
 
-	return &controller[T]{
+	c := &controller[T]{
 		options:    options,
 		informer:   informer,
 		reconciler: reconciler,
 		queue:      nil,
 	}
+	c.hasProcessed.UpstreamHasSynced = func() bool {
+		f := c.notificationsDelivered.Load()
+		if f == nil {
+			return false
+		}
+		return f.(func() bool)()
+	}
+	return c
 }
 
 // Runs the controller and returns an error explaining why running was stopped.
@@ -92,20 +107,22 @@ func (c *controller[T]) Run(ctx context.Context) error {
 	// would never shut down the workqueue
 	defer c.queue.ShutDown()
 
-	enqueue := func(obj interface{}) {
+	enqueue := func(obj interface{}, isInInitialList bool) {
 		var key string
 		var err error
 		if key, err = cache.DeletionHandlingMetaNamespaceKeyFunc(obj); err != nil {
 			utilruntime.HandleError(err)
 			return
 		}
+		if isInInitialList {
+			c.hasProcessed.Start(key)
+		}
+
 		c.queue.Add(key)
 	}
 
-	registration, err := c.informer.AddEventHandler(cache.ResourceEventHandlerFuncs{
-		AddFunc: func(obj interface{}) {
-			enqueue(obj)
-		},
+	registration, err := c.informer.AddEventHandler(cache.ResourceEventHandlerDetailedFuncs{
+		AddFunc: enqueue,
 		UpdateFunc: func(oldObj, newObj interface{}) {
 			oldMeta, err1 := meta.Accessor(oldObj)
 			newMeta, err2 := meta.Accessor(newObj)
@@ -126,11 +143,11 @@ func (c *controller[T]) Run(ctx context.Context) error {
 				return
 			}
 
-			enqueue(newObj)
+			enqueue(newObj, false)
 		},
 		DeleteFunc: func(obj interface{}) {
 			// Enqueue
-			enqueue(obj)
+			enqueue(obj, false)
 		},
 	})
 
@@ -139,9 +156,12 @@ func (c *controller[T]) Run(ctx context.Context) error {
 		return err
 	}
 
+	c.notificationsDelivered.Store(registration.HasSynced)
+
 	// Make sure event handler is removed from informer in case return early from
 	// an error
 	defer func() {
+		c.notificationsDelivered.Store(func() bool { return false })
 		// Remove event handler and Handle Error here. Error should only be raised
 		// for improper usage of event handler API.
 		if err := c.informer.RemoveEventHandler(registration); err != nil {
@@ -166,8 +186,8 @@ func (c *controller[T]) Run(ctx context.Context) error {
 	for i := uint(0); i < c.options.Workers; i++ {
 		waitGroup.Add(1)
 		go func() {
+			defer waitGroup.Done()
 			wait.Until(c.runWorker, time.Second, ctx.Done())
-			waitGroup.Done()
 		}()
 	}
 
@@ -188,7 +208,7 @@ func (c *controller[T]) Run(ctx context.Context) error {
 }
 
 func (c *controller[T]) HasSynced() bool {
-	return c.informer.HasSynced()
+	return c.hasProcessed.HasSynced()
 }
 
 func (c *controller[T]) runWorker() {
@@ -220,6 +240,7 @@ func (c *controller[T]) runWorker() {
 				// but the key is invalid so there is no point in doing that)
 				return fmt.Errorf("expected string in workqueue but got %#v", obj)
 			}
+			defer c.hasProcessed.Finished(key)
 
 			if err := c.reconcile(key); err != nil {
 				// Put the item back on the workqueue to handle any transient errors.

vendor/k8s.io/apiserver/pkg/admission/plugin/validatingadmissionpolicy/matcher.go

@@ -0,0 +1,83 @@
+/*
+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 validatingadmissionpolicy
+
+import (
+	"k8s.io/api/admissionregistration/v1beta1"
+	corev1 "k8s.io/api/core/v1"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/labels"
+	"k8s.io/apimachinery/pkg/runtime/schema"
+	"k8s.io/apiserver/pkg/admission"
+	"k8s.io/apiserver/pkg/admission/plugin/validatingadmissionpolicy/matching"
+)
+
+var _ matching.MatchCriteria = &matchCriteria{}
+
+type matchCriteria struct {
+	constraints *v1beta1.MatchResources
+}
+
+// GetParsedNamespaceSelector returns the converted LabelSelector which implements labels.Selector
+func (m *matchCriteria) GetParsedNamespaceSelector() (labels.Selector, error) {
+	return metav1.LabelSelectorAsSelector(m.constraints.NamespaceSelector)
+}
+
+// GetParsedObjectSelector returns the converted LabelSelector which implements labels.Selector
+func (m *matchCriteria) GetParsedObjectSelector() (labels.Selector, error) {
+	return metav1.LabelSelectorAsSelector(m.constraints.ObjectSelector)
+}
+
+// GetMatchResources returns the matchConstraints
+func (m *matchCriteria) GetMatchResources() v1beta1.MatchResources {
+	return *m.constraints
+}
+
+type matcher struct {
+	Matcher *matching.Matcher
+}
+
+func NewMatcher(m *matching.Matcher) Matcher {
+	return &matcher{
+		Matcher: m,
+	}
+}
+
+// ValidateInitialization checks if Matcher is initialized.
+func (c *matcher) ValidateInitialization() error {
+	return c.Matcher.ValidateInitialization()
+}
+
+// DefinitionMatches returns whether this ValidatingAdmissionPolicy matches the provided admission resource request
+func (c *matcher) DefinitionMatches(a admission.Attributes, o admission.ObjectInterfaces, definition *v1beta1.ValidatingAdmissionPolicy) (bool, schema.GroupVersionResource, schema.GroupVersionKind, error) {
+	criteria := matchCriteria{constraints: definition.Spec.MatchConstraints}
+	return c.Matcher.Matches(a, o, &criteria)
+}
+
+// BindingMatches returns whether this ValidatingAdmissionPolicyBinding matches the provided admission resource request
+func (c *matcher) BindingMatches(a admission.Attributes, o admission.ObjectInterfaces, binding *v1beta1.ValidatingAdmissionPolicyBinding) (bool, error) {
+	if binding.Spec.MatchResources == nil {
+		return true, nil
+	}
+	criteria := matchCriteria{constraints: binding.Spec.MatchResources}
+	isMatch, _, _, err := c.Matcher.Matches(a, o, &criteria)
+	return isMatch, err
+}
+
+func (c *matcher) GetNamespace(name string) (*corev1.Namespace, error) {
+	return c.Matcher.GetNamespace(name)
+}

vendor/k8s.io/apiserver/pkg/admission/plugin/validatingadmissionpolicy/matching/matching.go

@@ -20,7 +20,8 @@ import (
 	"fmt"
 
 	v1 "k8s.io/api/admissionregistration/v1"
-	"k8s.io/api/admissionregistration/v1alpha1"
+	"k8s.io/api/admissionregistration/v1beta1"
+	corev1 "k8s.io/api/core/v1"
 	"k8s.io/apimachinery/pkg/runtime/schema"
 	"k8s.io/apiserver/pkg/admission"
 	"k8s.io/client-go/kubernetes"
@@ -35,7 +36,7 @@ type MatchCriteria interface {
 	namespace.NamespaceSelectorProvider
 	object.ObjectSelectorProvider
 
-	GetMatchResources() v1alpha1.MatchResources
+	GetMatchResources() v1beta1.MatchResources
 }
 
 // Matcher decides if a request matches against matchCriteria
@@ -44,6 +45,10 @@ type Matcher struct {
 	objectMatcher    *object.Matcher
 }
 
+func (m *Matcher) GetNamespace(name string) (*corev1.Namespace, error) {
+	return m.namespaceMatcher.GetNamespace(name)
+}
+
 // NewMatcher initialize the matcher with dependencies requires
 func NewMatcher(
 	namespaceLister listersv1.NamespaceLister,
@@ -66,56 +71,60 @@ func (m *Matcher) ValidateInitialization() error {
 	return nil
 }
 
-func (m *Matcher) Matches(attr admission.Attributes, o admission.ObjectInterfaces, criteria MatchCriteria) (bool, schema.GroupVersionKind, error) {
+func (m *Matcher) Matches(attr admission.Attributes, o admission.ObjectInterfaces, criteria MatchCriteria) (bool, schema.GroupVersionResource, schema.GroupVersionKind, error) {
 	matches, matchNsErr := m.namespaceMatcher.MatchNamespaceSelector(criteria, attr)
 	// Should not return an error here for policy which do not apply to the request, even if err is an unexpected scenario.
 	if !matches && matchNsErr == nil {
-		return false, schema.GroupVersionKind{}, nil
+		return false, schema.GroupVersionResource{}, schema.GroupVersionKind{}, nil
 	}
 
 	matches, matchObjErr := m.objectMatcher.MatchObjectSelector(criteria, attr)
 	// Should not return an error here for policy which do not apply to the request, even if err is an unexpected scenario.
 	if !matches && matchObjErr == nil {
-		return false, schema.GroupVersionKind{}, nil
+		return false, schema.GroupVersionResource{}, schema.GroupVersionKind{}, nil
 	}
 
 	matchResources := criteria.GetMatchResources()
 	matchPolicy := matchResources.MatchPolicy
-	if isExcluded, _, err := matchesResourceRules(matchResources.ExcludeResourceRules, matchPolicy, attr, o); isExcluded || err != nil {
-		return false, schema.GroupVersionKind{}, err
+	if isExcluded, _, _, err := matchesResourceRules(matchResources.ExcludeResourceRules, matchPolicy, attr, o); isExcluded || err != nil {
+		return false, schema.GroupVersionResource{}, schema.GroupVersionKind{}, err
 	}
 
 	var (
-		isMatch   bool
-		matchKind schema.GroupVersionKind
-		matchErr  error
+		isMatch       bool
+		matchResource schema.GroupVersionResource
+		matchKind     schema.GroupVersionKind
+		matchErr      error
 	)
 	if len(matchResources.ResourceRules) == 0 {
 		isMatch = true
 		matchKind = attr.GetKind()
+		matchResource = attr.GetResource()
 	} else {
-		isMatch, matchKind, matchErr = matchesResourceRules(matchResources.ResourceRules, matchPolicy, attr, o)
+		isMatch, matchResource, matchKind, matchErr = matchesResourceRules(matchResources.ResourceRules, matchPolicy, attr, o)
 	}
 	if matchErr != nil {
-		return false, schema.GroupVersionKind{}, matchErr
+		return false, schema.GroupVersionResource{}, schema.GroupVersionKind{}, matchErr
 	}
 	if !isMatch {
-		return false, schema.GroupVersionKind{}, nil
+		return false, schema.GroupVersionResource{}, schema.GroupVersionKind{}, nil
 	}
 
 	// now that we know this applies to this request otherwise, if there were selector errors, return them
 	if matchNsErr != nil {
-		return false, schema.GroupVersionKind{}, matchNsErr
+		return false, schema.GroupVersionResource{}, schema.GroupVersionKind{}, matchNsErr
 	}
 	if matchObjErr != nil {
-		return false, schema.GroupVersionKind{}, matchObjErr
+		return false, schema.GroupVersionResource{}, schema.GroupVersionKind{}, matchObjErr
 	}
 
-	return true, matchKind, nil
+	return true, matchResource, matchKind, nil
 }
 
-func matchesResourceRules(namedRules []v1alpha1.NamedRuleWithOperations, matchPolicy *v1alpha1.MatchPolicyType, attr admission.Attributes, o admission.ObjectInterfaces) (bool, schema.GroupVersionKind, error) {
+func matchesResourceRules(namedRules []v1beta1.NamedRuleWithOperations, matchPolicy *v1beta1.MatchPolicyType, attr admission.Attributes, o admission.ObjectInterfaces) (bool, schema.GroupVersionResource, schema.GroupVersionKind, error) {
 	matchKind := attr.GetKind()
+	matchResource := attr.GetResource()
+
 	for _, namedRule := range namedRules {
 		rule := v1.RuleWithOperations(namedRule.RuleWithOperations)
 		ruleMatcher := rules.Matcher{
@@ -127,22 +136,22 @@ func matchesResourceRules(namedRules []v1alpha1.NamedRuleWithOperations, matchPo
 		}
 		// an empty name list always matches
 		if len(namedRule.ResourceNames) == 0 {
-			return true, matchKind, nil
+			return true, matchResource, matchKind, nil
 		}
 		// TODO: GetName() can return an empty string if the user is relying on
 		// the API server to generate the name... figure out what to do for this edge case
 		name := attr.GetName()
 		for _, matchedName := range namedRule.ResourceNames {
 			if name == matchedName {
-				return true, matchKind, nil
+				return true, matchResource, matchKind, nil
 			}
 		}
 	}
 
 	// if match policy is undefined or exact, don't perform fuzzy matching
 	// note that defaulting to fuzzy matching is set by the API
-	if matchPolicy == nil || *matchPolicy == v1alpha1.Exact {
-		return false, schema.GroupVersionKind{}, nil
+	if matchPolicy == nil || *matchPolicy == v1beta1.Exact {
+		return false, schema.GroupVersionResource{}, schema.GroupVersionKind{}, nil
 	}
 
 	attrWithOverride := &attrWithResourceOverride{Attributes: attr}
@@ -164,11 +173,11 @@ func matchesResourceRules(namedRules []v1alpha1.NamedRuleWithOperations, matchPo
 			}
 			matchKind = o.GetEquivalentResourceMapper().KindFor(equivalent, attr.GetSubresource())
 			if matchKind.Empty() {
-				return false, schema.GroupVersionKind{}, fmt.Errorf("unable to convert to %v: unknown kind", equivalent)
+				return false, schema.GroupVersionResource{}, schema.GroupVersionKind{}, fmt.Errorf("unable to convert to %v: unknown kind", equivalent)
 			}
 			// an empty name list always matches
 			if len(namedRule.ResourceNames) == 0 {
-				return true, matchKind, nil
+				return true, equivalent, matchKind, nil
 			}
 
 			// TODO: GetName() can return an empty string if the user is relying on
@@ -176,12 +185,12 @@ func matchesResourceRules(namedRules []v1alpha1.NamedRuleWithOperations, matchPo
 			name := attr.GetName()
 			for _, matchedName := range namedRule.ResourceNames {
 				if name == matchedName {
-					return true, matchKind, nil
+					return true, equivalent, matchKind, nil
 				}
 			}
 		}
 	}
-	return false, schema.GroupVersionKind{}, nil
+	return false, schema.GroupVersionResource{}, schema.GroupVersionKind{}, nil
 }
 
 type attrWithResourceOverride struct {

vendor/k8s.io/apiserver/pkg/admission/plugin/validatingadmissionpolicy/message.go

@@ -0,0 +1,36 @@
+/*
+Copyright 2023 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 validatingadmissionpolicy
+
+import (
+	celgo "github.com/google/cel-go/cel"
+	"k8s.io/apiserver/pkg/admission/plugin/cel"
+)
+
+var _ cel.ExpressionAccessor = (*MessageExpressionCondition)(nil)
+
+type MessageExpressionCondition struct {
+	MessageExpression string
+}
+
+func (m *MessageExpressionCondition) GetExpression() string {
+	return m.MessageExpression
+}
+
+func (m *MessageExpressionCondition) ReturnTypes() []*celgo.Type {
+	return []*celgo.Type{celgo.StringType}
+}

vendor/k8s.io/apiserver/pkg/admission/plugin/validatingadmissionpolicy/policy_decision.go

@@ -20,37 +20,54 @@ import (
 	"net/http"
 	"time"
 
-	"k8s.io/api/admissionregistration/v1alpha1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 )
 
-type policyDecisionAction string
+type PolicyDecisionAction string
 
 const (
-	actionAdmit policyDecisionAction = "admit"
-	actionDeny  policyDecisionAction = "deny"
+	ActionAdmit PolicyDecisionAction = "admit"
+	ActionDeny  PolicyDecisionAction = "deny"
 )
 
-type policyDecisionEvaluation string
+type PolicyDecisionEvaluation string
 
 const (
-	evalAdmit policyDecisionEvaluation = "admit"
-	evalError policyDecisionEvaluation = "error"
-	evalDeny  policyDecisionEvaluation = "deny"
+	EvalAdmit PolicyDecisionEvaluation = "admit"
+	EvalError PolicyDecisionEvaluation = "error"
+	EvalDeny  PolicyDecisionEvaluation = "deny"
 )
 
-type policyDecision struct {
-	action     policyDecisionAction
-	evaluation policyDecisionEvaluation
-	message    string
-	reason     metav1.StatusReason
-	elapsed    time.Duration
+// PolicyDecision contains the action determined from a cel evaluation along with metadata such as message, reason and duration
+type PolicyDecision struct {
+	Action     PolicyDecisionAction
+	Evaluation PolicyDecisionEvaluation
+	Message    string
+	Reason     metav1.StatusReason
+	Elapsed    time.Duration
 }
 
-type policyDecisionWithMetadata struct {
-	policyDecision
-	definition *v1alpha1.ValidatingAdmissionPolicy
-	binding    *v1alpha1.ValidatingAdmissionPolicyBinding
+type PolicyAuditAnnotationAction string
+
+const (
+	// AuditAnnotationActionPublish indicates that the audit annotation should be
+	// published with the audit event.
+	AuditAnnotationActionPublish PolicyAuditAnnotationAction = "publish"
+	// AuditAnnotationActionError indicates that the valueExpression resulted
+	// in an error.
+	AuditAnnotationActionError PolicyAuditAnnotationAction = "error"
+	// AuditAnnotationActionExclude indicates that the audit annotation should be excluded
+	// because the valueExpression evaluated to null, or because FailurePolicy is Ignore
+	// and the expression failed with a parse error, type check error, or runtime error.
+	AuditAnnotationActionExclude PolicyAuditAnnotationAction = "exclude"
+)
+
+type PolicyAuditAnnotation struct {
+	Key     string
+	Value   string
+	Elapsed time.Duration
+	Action  PolicyAuditAnnotationAction
+	Error   string
 }
 
 func reasonToCode(r metav1.StatusReason) int32 {

vendor/k8s.io/apiserver/pkg/admission/plugin/validatingadmissionpolicy/typechecking.go

@@ -0,0 +1,423 @@
+/*
+Copyright 2023 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 validatingadmissionpolicy
+
+import (
+	"errors"
+	"fmt"
+	"sort"
+	"strings"
+	"time"
+
+	"github.com/google/cel-go/cel"
+
+	"k8s.io/api/admissionregistration/v1beta1"
+	"k8s.io/apimachinery/pkg/api/meta"
+	"k8s.io/apimachinery/pkg/runtime/schema"
+	"k8s.io/apimachinery/pkg/util/sets"
+	"k8s.io/apimachinery/pkg/util/validation/field"
+	"k8s.io/apimachinery/pkg/util/version"
+	plugincel "k8s.io/apiserver/pkg/admission/plugin/cel"
+	apiservercel "k8s.io/apiserver/pkg/cel"
+	"k8s.io/apiserver/pkg/cel/common"
+	"k8s.io/apiserver/pkg/cel/environment"
+	"k8s.io/apiserver/pkg/cel/library"
+	"k8s.io/apiserver/pkg/cel/openapi"
+	"k8s.io/apiserver/pkg/cel/openapi/resolver"
+	"k8s.io/klog/v2"
+)
+
+const maxTypesToCheck = 10
+
+type TypeChecker struct {
+	SchemaResolver resolver.SchemaResolver
+	RestMapper     meta.RESTMapper
+}
+
+// TypeCheckingContext holds information about the policy being type-checked.
+// The struct is opaque to the caller.
+type TypeCheckingContext struct {
+	gvks          []schema.GroupVersionKind
+	declTypes     []*apiservercel.DeclType
+	paramGVK      schema.GroupVersionKind
+	paramDeclType *apiservercel.DeclType
+}
+
+type typeOverwrite struct {
+	object *apiservercel.DeclType
+	params *apiservercel.DeclType
+}
+
+// TypeCheckingResult holds the issues found during type checking, any returned
+// error, and the gvk that the type checking is performed against.
+type TypeCheckingResult struct {
+	// GVK is the associated GVK
+	GVK schema.GroupVersionKind
+	// Issues contain machine-readable information about the typechecking result.
+	Issues *cel.Issues
+	// Err is the possible error that was encounter during type checking.
+	Err error
+}
+
+// TypeCheckingResults is a collection of TypeCheckingResult
+type TypeCheckingResults []*TypeCheckingResult
+
+func (rs TypeCheckingResults) String() string {
+	var messages []string
+	for _, r := range rs {
+		message := r.String()
+		if message != "" {
+			messages = append(messages, message)
+		}
+	}
+	return strings.Join(messages, "\n")
+}
+
+// String converts the result to human-readable form as a string.
+func (r *TypeCheckingResult) String() string {
+	if r.Issues == nil && r.Err == nil {
+		return ""
+	}
+	if r.Err != nil {
+		return fmt.Sprintf("%v: type checking error: %v\n", r.GVK, r.Err)
+	}
+	return fmt.Sprintf("%v: %s\n", r.GVK, r.Issues)
+}
+
+// Check preforms the type check against the given policy, and format the result
+// as []ExpressionWarning that is ready to be set in policy.Status
+// The result is nil if type checking returns no warning.
+// The policy object is NOT mutated. The caller should update Status accordingly
+func (c *TypeChecker) Check(policy *v1beta1.ValidatingAdmissionPolicy) []v1beta1.ExpressionWarning {
+	ctx := c.CreateContext(policy)
+
+	// warnings to return, note that the capacity is optimistically set to zero
+	var warnings []v1beta1.ExpressionWarning // intentionally not setting capacity
+
+	// check main validation expressions and their message expressions, located in spec.validations[*]
+	fieldRef := field.NewPath("spec", "validations")
+	for i, v := range policy.Spec.Validations {
+		results := c.CheckExpression(ctx, v.Expression)
+		if len(results) != 0 {
+			warnings = append(warnings, v1beta1.ExpressionWarning{
+				FieldRef: fieldRef.Index(i).Child("expression").String(),
+				Warning:  results.String(),
+			})
+		}
+		// Note that MessageExpression is optional
+		if v.MessageExpression == "" {
+			continue
+		}
+		results = c.CheckExpression(ctx, v.MessageExpression)
+		if len(results) != 0 {
+			warnings = append(warnings, v1beta1.ExpressionWarning{
+				FieldRef: fieldRef.Index(i).Child("messageExpression").String(),
+				Warning:  results.String(),
+			})
+		}
+	}
+
+	return warnings
+}
+
+// CreateContext resolves all types and their schemas from a policy definition and creates the context.
+func (c *TypeChecker) CreateContext(policy *v1beta1.ValidatingAdmissionPolicy) *TypeCheckingContext {
+	ctx := new(TypeCheckingContext)
+	allGvks := c.typesToCheck(policy)
+	gvks := make([]schema.GroupVersionKind, 0, len(allGvks))
+	declTypes := make([]*apiservercel.DeclType, 0, len(allGvks))
+	for _, gvk := range allGvks {
+		declType, err := c.declType(gvk)
+		if err != nil {
+			// type checking errors MUST NOT alter the behavior of the policy
+			// even if an error occurs.
+			if !errors.Is(err, resolver.ErrSchemaNotFound) {
+				// Anything except ErrSchemaNotFound is an internal error
+				klog.V(2).ErrorS(err, "internal error: schema resolution failure", "gvk", gvk)
+			}
+			// skip for not found or internal error
+			continue
+		}
+		gvks = append(gvks, gvk)
+		declTypes = append(declTypes, declType)
+	}
+	ctx.gvks = gvks
+	ctx.declTypes = declTypes
+
+	paramsGVK := c.paramsGVK(policy) // maybe empty, correctly handled
+	paramsDeclType, err := c.declType(paramsGVK)
+	if err != nil {
+		if !errors.Is(err, resolver.ErrSchemaNotFound) {
+			klog.V(2).ErrorS(err, "internal error: cannot resolve schema for params", "gvk", paramsGVK)
+		}
+		paramsDeclType = nil
+	}
+	ctx.paramGVK = paramsGVK
+	ctx.paramDeclType = paramsDeclType
+	return ctx
+}
+
+// CheckExpression type checks a single expression, given the context
+func (c *TypeChecker) CheckExpression(ctx *TypeCheckingContext, expression string) TypeCheckingResults {
+	var results TypeCheckingResults
+	for i, gvk := range ctx.gvks {
+		declType := ctx.declTypes[i]
+		// TODO(jiahuif) hasAuthorizer always true for now, will change after expending type checking to all fields.
+		issues, err := c.checkExpression(expression, ctx.paramDeclType != nil, true, typeOverwrite{
+			object: declType,
+			params: ctx.paramDeclType,
+		})
+		if issues != nil || err != nil {
+			results = append(results, &TypeCheckingResult{Issues: issues, Err: err, GVK: gvk})
+		}
+	}
+	return results
+}
+
+func generateUniqueTypeName(kind string) string {
+	return fmt.Sprintf("%s%d", kind, time.Now().Nanosecond())
+}
+
+func (c *TypeChecker) declType(gvk schema.GroupVersionKind) (*apiservercel.DeclType, error) {
+	if gvk.Empty() {
+		return nil, nil
+	}
+	s, err := c.SchemaResolver.ResolveSchema(gvk)
+	if err != nil {
+		return nil, err
+	}
+	return common.SchemaDeclType(&openapi.Schema{Schema: s}, true).MaybeAssignTypeName(generateUniqueTypeName(gvk.Kind)), nil
+}
+
+func (c *TypeChecker) paramsGVK(policy *v1beta1.ValidatingAdmissionPolicy) schema.GroupVersionKind {
+	if policy.Spec.ParamKind == nil {
+		return schema.GroupVersionKind{}
+	}
+	gv, err := schema.ParseGroupVersion(policy.Spec.ParamKind.APIVersion)
+	if err != nil {
+		return schema.GroupVersionKind{}
+	}
+	return gv.WithKind(policy.Spec.ParamKind.Kind)
+}
+
+func (c *TypeChecker) checkExpression(expression string, hasParams, hasAuthorizer bool, types typeOverwrite) (*cel.Issues, error) {
+	env, err := buildEnv(hasParams, hasAuthorizer, types)
+	if err != nil {
+		return nil, err
+	}
+
+	// We cannot reuse an AST that is parsed by another env, so reparse it here.
+	// Compile = Parse + Check, we especially want the results of Check.
+	//
+	// Paradoxically, we discard the type-checked result and let the admission
+	// controller use the dynamic typed program.
+	// This is a compromise that is defined in the KEP. We can revisit this
+	// decision and expect a change with limited size.
+	_, issues := env.Compile(expression)
+	return issues, nil
+}
+
+// typesToCheck extracts a list of GVKs that needs type checking from the policy
+// the result is sorted in the order of Group, Version, and Kind
+func (c *TypeChecker) typesToCheck(p *v1beta1.ValidatingAdmissionPolicy) []schema.GroupVersionKind {
+	gvks := sets.New[schema.GroupVersionKind]()
+	if p.Spec.MatchConstraints == nil || len(p.Spec.MatchConstraints.ResourceRules) == 0 {
+		return nil
+	}
+	restMapperRefreshAttempted := false // at most once per policy, refresh RESTMapper and retry resolution.
+	for _, rule := range p.Spec.MatchConstraints.ResourceRules {
+		groups := extractGroups(&rule.Rule)
+		if len(groups) == 0 {
+			continue
+		}
+		versions := extractVersions(&rule.Rule)
+		if len(versions) == 0 {
+			continue
+		}
+		resources := extractResources(&rule.Rule)
+		if len(resources) == 0 {
+			continue
+		}
+		// sort GVRs so that the loop below provides
+		// consistent results.
+		sort.Strings(groups)
+		sort.Strings(versions)
+		sort.Strings(resources)
+		count := 0
+		for _, group := range groups {
+			for _, version := range versions {
+				for _, resource := range resources {
+					gvr := schema.GroupVersionResource{
+						Group:    group,
+						Version:  version,
+						Resource: resource,
+					}
+					resolved, err := c.RestMapper.KindsFor(gvr)
+					if err != nil {
+						if restMapperRefreshAttempted {
+							// RESTMapper refresh happens at most once per policy
+							continue
+						}
+						c.tryRefreshRESTMapper()
+						restMapperRefreshAttempted = true
+						resolved, err = c.RestMapper.KindsFor(gvr)
+						if err != nil {
+							continue
+						}
+					}
+					for _, r := range resolved {
+						if !r.Empty() {
+							gvks.Insert(r)
+							count++
+							// early return if maximum number of types are already
+							// collected
+							if count == maxTypesToCheck {
+								if gvks.Len() == 0 {
+									return nil
+								}
+								return sortGVKList(gvks.UnsortedList())
+							}
+						}
+					}
+				}
+			}
+		}
+	}
+	if gvks.Len() == 0 {
+		return nil
+	}
+	return sortGVKList(gvks.UnsortedList())
+}
+
+func extractGroups(rule *v1beta1.Rule) []string {
+	groups := make([]string, 0, len(rule.APIGroups))
+	for _, group := range rule.APIGroups {
+		// give up if wildcard
+		if strings.ContainsAny(group, "*") {
+			return nil
+		}
+		groups = append(groups, group)
+	}
+	return groups
+}
+
+func extractVersions(rule *v1beta1.Rule) []string {
+	versions := make([]string, 0, len(rule.APIVersions))
+	for _, version := range rule.APIVersions {
+		if strings.ContainsAny(version, "*") {
+			return nil
+		}
+		versions = append(versions, version)
+	}
+	return versions
+}
+
+func extractResources(rule *v1beta1.Rule) []string {
+	resources := make([]string, 0, len(rule.Resources))
+	for _, resource := range rule.Resources {
+		// skip wildcard and subresources
+		if strings.ContainsAny(resource, "*/") {
+			continue
+		}
+		resources = append(resources, resource)
+	}
+	return resources
+}
+
+// sortGVKList sorts the list by Group, Version, and Kind
+// returns the list itself.
+func sortGVKList(list []schema.GroupVersionKind) []schema.GroupVersionKind {
+	sort.Slice(list, func(i, j int) bool {
+		if g := strings.Compare(list[i].Group, list[j].Group); g != 0 {
+			return g < 0
+		}
+		if v := strings.Compare(list[i].Version, list[j].Version); v != 0 {
+			return v < 0
+		}
+		return strings.Compare(list[i].Kind, list[j].Kind) < 0
+	})
+	return list
+}
+
+// tryRefreshRESTMapper refreshes the RESTMapper if it supports refreshing.
+func (c *TypeChecker) tryRefreshRESTMapper() {
+	if r, ok := c.RestMapper.(meta.ResettableRESTMapper); ok {
+		r.Reset()
+	}
+}
+
+func buildEnv(hasParams bool, hasAuthorizer bool, types typeOverwrite) (*cel.Env, error) {
+	baseEnv := environment.MustBaseEnvSet(environment.DefaultCompatibilityVersion())
+	requestType := plugincel.BuildRequestType()
+	namespaceType := plugincel.BuildNamespaceType()
+
+	var varOpts []cel.EnvOption
+	var declTypes []*apiservercel.DeclType
+
+	// namespace, hand-crafted type
+	declTypes = append(declTypes, namespaceType)
+	varOpts = append(varOpts, createVariableOpts(namespaceType, plugincel.NamespaceVarName)...)
+
+	// request, hand-crafted type
+	declTypes = append(declTypes, requestType)
+	varOpts = append(varOpts, createVariableOpts(requestType, plugincel.RequestVarName)...)
+
+	// object and oldObject, same type, type(s) resolved from constraints
+	declTypes = append(declTypes, types.object)
+	varOpts = append(varOpts, createVariableOpts(types.object, plugincel.ObjectVarName, plugincel.OldObjectVarName)...)
+
+	// params, defined by ParamKind
+	if hasParams && types.params != nil {
+		declTypes = append(declTypes, types.params)
+		varOpts = append(varOpts, createVariableOpts(types.params, plugincel.ParamsVarName)...)
+	}
+
+	// authorizer, implicitly available to all expressions of a policy
+	if hasAuthorizer {
+		// we only need its structure but not the variable itself
+		varOpts = append(varOpts, cel.Variable("authorizer", library.AuthorizerType))
+	}
+
+	env, err := baseEnv.Extend(
+		environment.VersionedOptions{
+			// Feature epoch was actually 1.26, but we artificially set it to 1.0 because these
+			// options should always be present.
+			IntroducedVersion: version.MajorMinor(1, 0),
+			EnvOptions:        varOpts,
+			DeclTypes:         declTypes,
+		},
+	)
+	if err != nil {
+		return nil, err
+	}
+	return env.Env(environment.StoredExpressions)
+}
+
+// createVariableOpts creates a slice of EnvOption
+// that can be used for creating a CEL env containing variables of declType.
+// declType can be nil, in which case the variables will be of DynType.
+func createVariableOpts(declType *apiservercel.DeclType, variables ...string) []cel.EnvOption {
+	opts := make([]cel.EnvOption, 0, len(variables))
+	t := cel.DynType
+	if declType != nil {
+		t = declType.CelType()
+	}
+	for _, v := range variables {
+		opts = append(opts, cel.Variable(v, t))
+	}
+	return opts
+}

vendor/k8s.io/apiserver/pkg/admission/plugin/validatingadmissionpolicy/validator.go

@@ -17,302 +17,235 @@ limitations under the License.
 package validatingadmissionpolicy
 
 import (
+	"context"
 	"fmt"
-	"reflect"
 	"strings"
-	"time"
 
 	celtypes "github.com/google/cel-go/common/types"
-	"github.com/google/cel-go/interpreter"
 
-	admissionv1 "k8s.io/api/admission/v1"
-	"k8s.io/api/admissionregistration/v1alpha1"
-	authenticationv1 "k8s.io/api/authentication/v1"
+	v1 "k8s.io/api/admissionregistration/v1"
+	corev1 "k8s.io/api/core/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
-	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
-	"k8s.io/apimachinery/pkg/labels"
 	"k8s.io/apimachinery/pkg/runtime"
 	"k8s.io/apimachinery/pkg/runtime/schema"
 	"k8s.io/apiserver/pkg/admission"
-	"k8s.io/apiserver/pkg/admission/plugin/validatingadmissionpolicy/matching"
-	"k8s.io/apiserver/pkg/admission/plugin/webhook/generic"
+	"k8s.io/apiserver/pkg/admission/plugin/cel"
+	"k8s.io/apiserver/pkg/admission/plugin/webhook/matchconditions"
+	celconfig "k8s.io/apiserver/pkg/apis/cel"
+	"k8s.io/apiserver/pkg/authorization/authorizer"
+	apiservercel "k8s.io/apiserver/pkg/cel"
+	"k8s.io/klog/v2"
 )
 
-var _ ValidatorCompiler = &CELValidatorCompiler{}
-var _ matching.MatchCriteria = &matchCriteria{}
-
-type matchCriteria struct {
-	constraints *v1alpha1.MatchResources
+// validator implements the Validator interface
+type validator struct {
+	celMatcher            matchconditions.Matcher
+	validationFilter      cel.Filter
+	auditAnnotationFilter cel.Filter
+	messageFilter         cel.Filter
+	failPolicy            *v1.FailurePolicyType
 }
 
-// GetParsedNamespaceSelector returns the converted LabelSelector which implements labels.Selector
-func (m *matchCriteria) GetParsedNamespaceSelector() (labels.Selector, error) {
-	return metav1.LabelSelectorAsSelector(m.constraints.NamespaceSelector)
-}
-
-// GetParsedObjectSelector returns the converted LabelSelector which implements labels.Selector
-func (m *matchCriteria) GetParsedObjectSelector() (labels.Selector, error) {
-	return metav1.LabelSelectorAsSelector(m.constraints.ObjectSelector)
-}
-
-// GetMatchResources returns the matchConstraints
-func (m *matchCriteria) GetMatchResources() v1alpha1.MatchResources {
-	return *m.constraints
-}
-
-// CELValidatorCompiler implement the interface ValidatorCompiler.
-type CELValidatorCompiler struct {
-	Matcher *matching.Matcher
-}
-
-// DefinitionMatches returns whether this ValidatingAdmissionPolicy matches the provided admission resource request
-func (c *CELValidatorCompiler) DefinitionMatches(a admission.Attributes, o admission.ObjectInterfaces, definition *v1alpha1.ValidatingAdmissionPolicy) (bool, schema.GroupVersionKind, error) {
-	criteria := matchCriteria{constraints: definition.Spec.MatchConstraints}
-	return c.Matcher.Matches(a, o, &criteria)
-}
-
-// BindingMatches returns whether this ValidatingAdmissionPolicyBinding matches the provided admission resource request
-func (c *CELValidatorCompiler) BindingMatches(a admission.Attributes, o admission.ObjectInterfaces, binding *v1alpha1.ValidatingAdmissionPolicyBinding) (bool, error) {
-	if binding.Spec.MatchResources == nil {
-		return true, nil
-	}
-	criteria := matchCriteria{constraints: binding.Spec.MatchResources}
-	isMatch, _, err := c.Matcher.Matches(a, o, &criteria)
-	return isMatch, err
-}
-
-// ValidateInitialization checks if Matcher is initialized.
-func (c *CELValidatorCompiler) ValidateInitialization() error {
-	return c.Matcher.ValidateInitialization()
-}
-
-type validationActivation struct {
-	object, oldObject, params, request interface{}
-}
-
-// ResolveName returns a value from the activation by qualified name, or false if the name
-// could not be found.
-func (a *validationActivation) ResolveName(name string) (interface{}, bool) {
-	switch name {
-	case ObjectVarName:
-		return a.object, true
-	case OldObjectVarName:
-		return a.oldObject, true
-	case ParamsVarName:
-		return a.params, true
-	case RequestVarName:
-		return a.request, true
-	default:
-		return nil, false
+func NewValidator(validationFilter cel.Filter, celMatcher matchconditions.Matcher, auditAnnotationFilter, messageFilter cel.Filter, failPolicy *v1.FailurePolicyType) Validator {
+	return &validator{
+		celMatcher:            celMatcher,
+		validationFilter:      validationFilter,
+		auditAnnotationFilter: auditAnnotationFilter,
+		messageFilter:         messageFilter,
+		failPolicy:            failPolicy,
 	}
 }
 
-// Parent returns the parent of the current activation, may be nil.
-// If non-nil, the parent will be searched during resolve calls.
-func (a *validationActivation) Parent() interpreter.Activation {
-	return nil
+func policyDecisionActionForError(f v1.FailurePolicyType) PolicyDecisionAction {
+	if f == v1.Ignore {
+		return ActionAdmit
+	}
+	return ActionDeny
 }
 
-// Compile compiles the cel expression defined in ValidatingAdmissionPolicy
-func (c *CELValidatorCompiler) Compile(p *v1alpha1.ValidatingAdmissionPolicy) Validator {
-	if len(p.Spec.Validations) == 0 {
-		return nil
+func auditAnnotationEvaluationForError(f v1.FailurePolicyType) PolicyAuditAnnotationAction {
+	if f == v1.Ignore {
+		return AuditAnnotationActionExclude
 	}
-	hasParam := false
-	if p.Spec.ParamKind != nil {
-		hasParam = true
-	}
-	compilationResults := make([]CompilationResult, len(p.Spec.Validations))
-	for i, validation := range p.Spec.Validations {
-		compilationResults[i] = CompileValidatingPolicyExpression(validation.Expression, hasParam)
-	}
-	return &CELValidator{policy: p, compilationResults: compilationResults}
+	return AuditAnnotationActionError
 }
 
-// CELValidator implements the Validator interface
-type CELValidator struct {
-	policy             *v1alpha1.ValidatingAdmissionPolicy
-	compilationResults []CompilationResult
-}
+// Validate takes a list of Evaluation and a failure policy and converts them into actionable PolicyDecisions
+// runtimeCELCostBudget was added for testing purpose only. Callers should always use const RuntimeCELCostBudget from k8s.io/apiserver/pkg/apis/cel/config.go as input.
 
-func convertObjectToUnstructured(obj interface{}) (*unstructured.Unstructured, error) {
-	if obj == nil || reflect.ValueOf(obj).IsNil() {
-		return &unstructured.Unstructured{Object: nil}, nil
-	}
-	ret, err := runtime.DefaultUnstructuredConverter.ToUnstructured(obj)
-	if err != nil {
-		return nil, err
-	}
-	return &unstructured.Unstructured{Object: ret}, nil
-}
-
-func objectToResolveVal(r runtime.Object) (interface{}, error) {
-	if r == nil || reflect.ValueOf(r).IsNil() {
-		return nil, nil
-	}
-	v, err := convertObjectToUnstructured(r)
-	if err != nil {
-		return nil, err
-	}
-	return v.Object, nil
-}
-
-func policyDecisionActionForError(f v1alpha1.FailurePolicyType) policyDecisionAction {
-	if f == v1alpha1.Ignore {
-		return actionAdmit
-	}
-	return actionDeny
-}
-
-// Validate validates all cel expressions in Validator and returns a PolicyDecision for each CEL expression or returns an error.
-// An error will be returned if failed to convert the object/oldObject/params/request to unstructured.
-// Each PolicyDecision will have a decision and a message.
-// policyDecision.message will be empty if the decision is allowed and no error met.
-func (v *CELValidator) Validate(a admission.Attributes, o admission.ObjectInterfaces, versionedParams runtime.Object, matchKind schema.GroupVersionKind) ([]policyDecision, error) {
-	// TODO: replace unstructured with ref.Val for CEL variables when native type support is available
-
-	decisions := make([]policyDecision, len(v.compilationResults))
-	var err error
-	versionedAttr, err := generic.NewVersionedAttributes(a, matchKind, o)
-	if err != nil {
-		return nil, err
-	}
-	oldObjectVal, err := objectToResolveVal(versionedAttr.VersionedOldObject)
-	if err != nil {
-		return nil, err
-	}
-	objectVal, err := objectToResolveVal(versionedAttr.VersionedObject)
-	if err != nil {
-		return nil, err
-	}
-	paramsVal, err := objectToResolveVal(versionedParams)
-	if err != nil {
-		return nil, err
-	}
-	request := createAdmissionRequest(versionedAttr.Attributes)
-	requestVal, err := convertObjectToUnstructured(request)
-	if err != nil {
-		return nil, err
-	}
-	va := &validationActivation{
-		object:    objectVal,
-		oldObject: oldObjectVal,
-		params:    paramsVal,
-		request:   requestVal.Object,
-	}
-
-	var f v1alpha1.FailurePolicyType
-	if v.policy.Spec.FailurePolicy == nil {
-		f = v1alpha1.Fail
+func (v *validator) Validate(ctx context.Context, matchedResource schema.GroupVersionResource, versionedAttr *admission.VersionedAttributes, versionedParams runtime.Object, namespace *corev1.Namespace, runtimeCELCostBudget int64, authz authorizer.Authorizer) ValidateResult {
+	var f v1.FailurePolicyType
+	if v.failPolicy == nil {
+		f = v1.Fail
 	} else {
-		f = *v.policy.Spec.FailurePolicy
+		f = *v.failPolicy
 	}
 
-	for i, compilationResult := range v.compilationResults {
-		validation := v.policy.Spec.Validations[i]
+	if v.celMatcher != nil {
+		matchResults := v.celMatcher.Match(ctx, versionedAttr, versionedParams, authz)
+		if matchResults.Error != nil {
+			return ValidateResult{
+				Decisions: []PolicyDecision{
+					{
+						Action:     policyDecisionActionForError(f),
+						Evaluation: EvalError,
+						Message:    matchResults.Error.Error(),
+					},
+				},
+			}
+		}
 
-		var policyDecision = &decisions[i]
+		// if preconditions are not met, then do not return any validations
+		if !matchResults.Matches {
+			return ValidateResult{}
+		}
+	}
 
-		if compilationResult.Error != nil {
-			policyDecision.action = policyDecisionActionForError(f)
-			policyDecision.evaluation = evalError
-			policyDecision.message = fmt.Sprintf("compilation error: %v", compilationResult.Error)
+	optionalVars := cel.OptionalVariableBindings{VersionedParams: versionedParams, Authorizer: authz}
+	expressionOptionalVars := cel.OptionalVariableBindings{VersionedParams: versionedParams}
+	admissionRequest := cel.CreateAdmissionRequest(versionedAttr.Attributes, metav1.GroupVersionResource(matchedResource), metav1.GroupVersionKind(versionedAttr.VersionedKind))
+	// Decide which fields are exposed
+	ns := cel.CreateNamespaceObject(namespace)
+	evalResults, remainingBudget, err := v.validationFilter.ForInput(ctx, versionedAttr, admissionRequest, optionalVars, ns, runtimeCELCostBudget)
+	if err != nil {
+		return ValidateResult{
+			Decisions: []PolicyDecision{
+				{
+					Action:     policyDecisionActionForError(f),
+					Evaluation: EvalError,
+					Message:    err.Error(),
+				},
+			},
+		}
+	}
+	decisions := make([]PolicyDecision, len(evalResults))
+	messageResults, _, err := v.messageFilter.ForInput(ctx, versionedAttr, admissionRequest, expressionOptionalVars, ns, remainingBudget)
+	for i, evalResult := range evalResults {
+		var decision = &decisions[i]
+		// TODO: move this to generics
+		validation, ok := evalResult.ExpressionAccessor.(*ValidationCondition)
+		if !ok {
+			klog.Error("Invalid type conversion to ValidationCondition")
+			decision.Action = policyDecisionActionForError(f)
+			decision.Evaluation = EvalError
+			decision.Message = "Invalid type sent to validator, expected ValidationCondition"
 			continue
 		}
-		if compilationResult.Program == nil {
-			policyDecision.action = policyDecisionActionForError(f)
-			policyDecision.evaluation = evalError
-			policyDecision.message = "unexpected internal error compiling expression"
-			continue
+
+		var messageResult *cel.EvaluationResult
+		var messageError *apiservercel.Error
+		if len(messageResults) > i {
+			messageResult = &messageResults[i]
 		}
-		t1 := time.Now()
-		evalResult, _, err := compilationResult.Program.Eval(va)
-		elapsed := time.Since(t1)
-		policyDecision.elapsed = elapsed
-		if err != nil {
-			policyDecision.action = policyDecisionActionForError(f)
-			policyDecision.evaluation = evalError
-			policyDecision.message = fmt.Sprintf("expression '%v' resulted in error: %v", v.policy.Spec.Validations[i].Expression, err)
-		} else if evalResult != celtypes.True {
-			policyDecision.action = actionDeny
+		messageError, _ = err.(*apiservercel.Error)
+		if evalResult.Error != nil {
+			decision.Action = policyDecisionActionForError(f)
+			decision.Evaluation = EvalError
+			decision.Message = evalResult.Error.Error()
+		} else if messageError != nil &&
+			(messageError.Type == apiservercel.ErrorTypeInternal ||
+				(messageError.Type == apiservercel.ErrorTypeInvalid &&
+					strings.HasPrefix(messageError.Detail, "validation failed due to running out of cost budget"))) {
+			decision.Action = policyDecisionActionForError(f)
+			decision.Evaluation = EvalError
+			decision.Message = fmt.Sprintf("failed messageExpression: %s", err)
+		} else if evalResult.EvalResult != celtypes.True {
+			decision.Action = ActionDeny
 			if validation.Reason == nil {
-				policyDecision.reason = metav1.StatusReasonInvalid
+				decision.Reason = metav1.StatusReasonInvalid
 			} else {
-				policyDecision.reason = *validation.Reason
+				decision.Reason = *validation.Reason
 			}
-			if len(validation.Message) > 0 {
-				policyDecision.message = strings.TrimSpace(validation.Message)
-			} else {
-				policyDecision.message = fmt.Sprintf("failed expression: %v", strings.TrimSpace(validation.Expression))
+			// decide the failure message
+			var message string
+			// attempt to set message with messageExpression result
+			if messageResult != nil && messageResult.Error == nil && messageResult.EvalResult != nil {
+				// also fallback if the eval result is non-string (including null) or
+				// whitespaces.
+				if message, ok = messageResult.EvalResult.Value().(string); ok {
+					message = strings.TrimSpace(message)
+					// deny excessively long message from EvalResult
+					if len(message) > celconfig.MaxEvaluatedMessageExpressionSizeBytes {
+						klog.V(2).InfoS("excessively long message denied", "message", message)
+						message = ""
+					}
+					// deny message that contains newlines
+					if strings.ContainsAny(message, "\n") {
+						klog.V(2).InfoS("multi-line message denied", "message", message)
+						message = ""
+					}
+				}
 			}
-
+			if messageResult != nil && messageResult.Error != nil {
+				// log any error with messageExpression
+				klog.V(2).ErrorS(messageResult.Error, "error while evaluating messageExpression")
+			}
+			// fallback to set message to the custom message
+			if message == "" && len(validation.Message) > 0 {
+				message = strings.TrimSpace(validation.Message)
+			}
+			// fallback to use the expression to compose a message
+			if message == "" {
+				message = fmt.Sprintf("failed expression: %v", strings.TrimSpace(validation.Expression))
+			}
+			decision.Message = message
 		} else {
-			policyDecision.action = actionAdmit
-			policyDecision.evaluation = evalAdmit
+			decision.Action = ActionAdmit
+			decision.Evaluation = EvalAdmit
 		}
 	}
 
-	return decisions, nil
-}
-
-func createAdmissionRequest(attr admission.Attributes) *admissionv1.AdmissionRequest {
-	// FIXME: how to get resource GVK, GVR and subresource?
-	gvk := attr.GetKind()
-	gvr := attr.GetResource()
-	subresource := attr.GetSubresource()
-
-	requestGVK := attr.GetKind()
-	requestGVR := attr.GetResource()
-	requestSubResource := attr.GetSubresource()
-
-	aUserInfo := attr.GetUserInfo()
-	var userInfo authenticationv1.UserInfo
-	if aUserInfo != nil {
-		userInfo = authenticationv1.UserInfo{
-			Extra:    make(map[string]authenticationv1.ExtraValue),
-			Groups:   aUserInfo.GetGroups(),
-			UID:      aUserInfo.GetUID(),
-			Username: aUserInfo.GetName(),
-		}
-		// Convert the extra information in the user object
-		for key, val := range aUserInfo.GetExtra() {
-			userInfo.Extra[key] = authenticationv1.ExtraValue(val)
-		}
-	}
-
-	dryRun := attr.IsDryRun()
-
-	return &admissionv1.AdmissionRequest{
-		Kind: metav1.GroupVersionKind{
-			Group:   gvk.Group,
-			Kind:    gvk.Kind,
-			Version: gvk.Version,
-		},
-		Resource: metav1.GroupVersionResource{
-			Group:    gvr.Group,
-			Resource: gvr.Resource,
-			Version:  gvr.Version,
-		},
-		SubResource: subresource,
-		RequestKind: &metav1.GroupVersionKind{
-			Group:   requestGVK.Group,
-			Kind:    requestGVK.Kind,
-			Version: requestGVK.Version,
-		},
-		RequestResource: &metav1.GroupVersionResource{
-			Group:    requestGVR.Group,
-			Resource: requestGVR.Resource,
-			Version:  requestGVR.Version,
-		},
-		RequestSubResource: requestSubResource,
-		Name:               attr.GetName(),
-		Namespace:          attr.GetNamespace(),
-		Operation:          admissionv1.Operation(attr.GetOperation()),
-		UserInfo:           userInfo,
-		// Leave Object and OldObject unset since we don't provide access to them via request
-		DryRun: &dryRun,
-		Options: runtime.RawExtension{
-			Object: attr.GetOperationOptions(),
-		},
-	}
+	options := cel.OptionalVariableBindings{VersionedParams: versionedParams}
+	auditAnnotationEvalResults, _, err := v.auditAnnotationFilter.ForInput(ctx, versionedAttr, admissionRequest, options, namespace, runtimeCELCostBudget)
+	if err != nil {
+		return ValidateResult{
+			Decisions: []PolicyDecision{
+				{
+					Action:     policyDecisionActionForError(f),
+					Evaluation: EvalError,
+					Message:    err.Error(),
+				},
+			},
+		}
+	}
+
+	auditAnnotationResults := make([]PolicyAuditAnnotation, len(auditAnnotationEvalResults))
+	for i, evalResult := range auditAnnotationEvalResults {
+		if evalResult.ExpressionAccessor == nil {
+			continue
+		}
+		var auditAnnotationResult = &auditAnnotationResults[i]
+		// TODO: move this to generics
+		validation, ok := evalResult.ExpressionAccessor.(*AuditAnnotationCondition)
+		if !ok {
+			klog.Error("Invalid type conversion to AuditAnnotationCondition")
+			auditAnnotationResult.Action = auditAnnotationEvaluationForError(f)
+			auditAnnotationResult.Error = fmt.Sprintf("Invalid type sent to validator, expected AuditAnnotationCondition but got %T", evalResult.ExpressionAccessor)
+			continue
+		}
+		auditAnnotationResult.Key = validation.Key
+
+		if evalResult.Error != nil {
+			auditAnnotationResult.Action = auditAnnotationEvaluationForError(f)
+			auditAnnotationResult.Error = evalResult.Error.Error()
+		} else {
+			switch evalResult.EvalResult.Type() {
+			case celtypes.StringType:
+				value := strings.TrimSpace(evalResult.EvalResult.Value().(string))
+				if len(value) == 0 {
+					auditAnnotationResult.Action = AuditAnnotationActionExclude
+				} else {
+					auditAnnotationResult.Action = AuditAnnotationActionPublish
+					auditAnnotationResult.Value = value
+				}
+			case celtypes.NullType:
+				auditAnnotationResult.Action = AuditAnnotationActionExclude
+			default:
+				auditAnnotationResult.Action = AuditAnnotationActionError
+				auditAnnotationResult.Error = fmt.Sprintf("valueExpression '%v' resulted in unsupported return type: %v. "+
+					"Return type must be either string or null.", validation.ValueExpression, evalResult.EvalResult.Type())
+			}
+		}
+	}
+	return ValidateResult{Decisions: decisions, AuditAnnotations: auditAnnotationResults}
 }