func isLimitSynced(received, expected kapi.ResourceList) bool {
resourceNames := quota.ResourceNames(expected)
masked := quota.Mask(received, resourceNames)
if len(masked) != len(expected) {
return false
}
if le, _ := quota.LessThanOrEqual(masked, expected); !le {
return false
}
if le, _ := quota.LessThanOrEqual(expected, masked); !le {
return false
}
return true
}
func isUsageSynced(received, expected kapi.ResourceList, expectedIsUpperLimit bool) bool {
resourceNames := quota.ResourceNames(expected)
masked := quota.Mask(received, resourceNames)
if len(masked) != len(expected) {
return false
}
if expectedIsUpperLimit {
if le, _ := quota.LessThanOrEqual(masked, expected); !le {
return false
}
} else {
if le, _ := quota.LessThanOrEqual(expected, masked); !le {
return false
}
}
return true
}
// admitBlobWrite checks whether the blob does not exceed image quota, if set. Returns
// ErrAccessDenied error if the quota is exceeded.
func admitBlobWrite(ctx context.Context, repo *repository) error {
rqs, err := repo.quotaClient.ResourceQuotas(repo.namespace).List(kapi.ListOptions{})
if err != nil {
if kerrors.IsForbidden(err) {
context.GetLogger(ctx).Warnf("Cannot list resourcequotas because of outdated cluster roles: %v", err)
return nil
}
context.GetLogger(ctx).Errorf("Failed to list resourcequotas: %v", err)
return err
}
usage := kapi.ResourceList{
// we are about to tag a single image to an image stream
imageapi.ResourceImages: *resource.NewQuantity(1, resource.DecimalSI),
}
resources := quota.ResourceNames(usage)
for _, rq := range rqs.Items {
newUsage := quota.Add(usage, rq.Status.Used)
newUsage = quota.Mask(newUsage, resources)
requested := quota.Mask(rq.Spec.Hard, resources)
allowed, exceeded := quota.LessThanOrEqual(newUsage, requested)
if !allowed {
details := make([]string, len(exceeded))
by := quota.Subtract(newUsage, requested)
for i, r := range exceeded {
details[i] = fmt.Sprintf("%s limited to %s by %s", r, requested[r], by[r])
}
context.GetLogger(ctx).Error("Refusing to write blob exceeding quota: " + strings.Join(details, ", "))
return distribution.ErrAccessDenied
}
}
return nil
}
func TestLimitVerifier(t *testing.T) {
makeISForbiddenError := func(isName string, exceeded []kapi.ResourceName) error {
if len(exceeded) == 0 {
return nil
}
exceededStrings := []string{}
for _, r := range exceeded {
exceededStrings = append(exceededStrings, string(r))
}
sort.Strings(exceededStrings)
err := fmt.Errorf("exceeded %s", strings.Join(exceededStrings, ","))
return kapierrors.NewForbidden(api.Resource("ImageStream"), isName, err)
}
makeISEvaluator := func(maxImages, maxImageTags int64) func(string, *api.ImageStream) error {
return func(ns string, is *api.ImageStream) error {
limit := kapi.ResourceList{
api.ResourceImageStreamImages: *resource.NewQuantity(maxImages, resource.DecimalSI),
api.ResourceImageStreamTags: *resource.NewQuantity(maxImageTags, resource.DecimalSI),
}
usage := admission.GetImageStreamUsage(is)
if less, exceeded := kquota.LessThanOrEqual(usage, limit); !less {
return makeISForbiddenError(is.Name, exceeded)
}
return nil
}
}
tests := []struct {
name string
isEvaluator func(string, *api.ImageStream) error
is api.ImageStream
expected field.ErrorList
}{
{
name: "no limit",
is: api.ImageStream{
ObjectMeta: kapi.ObjectMeta{
Namespace: "test",
Name: "is",
},
Status: api.ImageStreamStatus{
Tags: map[string]api.TagEventList{
"latest": {
Items: []api.TagEvent{
{
DockerImageReference: testutil.MakeDockerImageReference("test", "is", testutil.BaseImageWith1LayerDigest),
Image: testutil.BaseImageWith1LayerDigest,
},
},
},
},
},
},
},
{
name: "below limit",
is: api.ImageStream{
ObjectMeta: kapi.ObjectMeta{
Namespace: "test",
Name: "is",
},
Status: api.ImageStreamStatus{
Tags: map[string]api.TagEventList{
"latest": {
Items: []api.TagEvent{
{
DockerImageReference: testutil.MakeDockerImageReference("test", "is", testutil.BaseImageWith1LayerDigest),
Image: testutil.BaseImageWith1LayerDigest,
},
},
},
},
},
},
isEvaluator: makeISEvaluator(1, 0),
},
{
name: "exceed images",
is: api.ImageStream{
ObjectMeta: kapi.ObjectMeta{
Namespace: "test",
Name: "is",
},
Status: api.ImageStreamStatus{
Tags: map[string]api.TagEventList{
"latest": {
Items: []api.TagEvent{
{
DockerImageReference: testutil.MakeDockerImageReference("test", "is", testutil.BaseImageWith1LayerDigest),
Image: testutil.BaseImageWith1LayerDigest,
},
},
},
"oldest": {
Items: []api.TagEvent{
{
DockerImageReference: testutil.MakeDockerImageReference("test", "is", testutil.BaseImageWith2LayersDigest),
Image: testutil.BaseImageWith2LayersDigest,
},
},
},
},
},
},
isEvaluator: makeISEvaluator(1, 0),
expected: field.ErrorList{
field.Forbidden(field.NewPath("imageStream"), makeISForbiddenError("is", []kapi.ResourceName{api.ResourceImageStreamImages}).Error()),
},
},
{
name: "exceed tags",
is: api.ImageStream{
ObjectMeta: kapi.ObjectMeta{
Namespace: "test",
Name: "is",
},
Spec: api.ImageStreamSpec{
Tags: map[string]api.TagReference{
"new": {
Name: "new",
From: &kapi.ObjectReference{
Kind: "DockerImage",
Name: testutil.MakeDockerImageReference("test", "is", testutil.ChildImageWith2LayersDigest),
},
},
},
},
},
isEvaluator: makeISEvaluator(0, 0),
expected: field.ErrorList{
field.Forbidden(field.NewPath("imageStream"), makeISForbiddenError("is", []kapi.ResourceName{api.ResourceImageStreamTags}).Error()),
},
},
{
name: "exceed images and tags",
is: api.ImageStream{
ObjectMeta: kapi.ObjectMeta{
Namespace: "test",
Name: "is",
},
Spec: api.ImageStreamSpec{
Tags: map[string]api.TagReference{
"new": {
Name: "new",
From: &kapi.ObjectReference{
Kind: "DockerImage",
Name: testutil.MakeDockerImageReference("test", "other", testutil.BaseImageWith1LayerDigest),
},
},
},
},
Status: api.ImageStreamStatus{
Tags: map[string]api.TagEventList{
"latest": {
Items: []api.TagEvent{
{
DockerImageReference: testutil.MakeDockerImageReference("test", "other", testutil.BaseImageWith1LayerDigest),
Image: testutil.BaseImageWith1LayerDigest,
},
},
},
},
},
},
isEvaluator: makeISEvaluator(0, 0),
expected: field.ErrorList{
field.Forbidden(field.NewPath("imageStream"), makeISForbiddenError("is", []kapi.ResourceName{api.ResourceImageStreamImages, api.ResourceImageStreamTags}).Error()),
},
},
}
for _, tc := range tests {
sar := &fakeSubjectAccessReviewRegistry{
allow: true,
}
tagVerifier := &TagVerifier{sar}
s := &Strategy{
tagVerifier: tagVerifier,
limitVerifier: &testutil.FakeImageStreamLimitVerifier{
ImageStreamEvaluator: tc.isEvaluator,
},
defaultRegistry: &fakeDefaultRegistry{},
}
ctx := kapi.WithUser(kapi.NewDefaultContext(), &fakeUser{})
errList := s.Validate(ctx, &tc.is)
if e, a := tc.expected, errList; !reflect.DeepEqual(e, a) {
t.Errorf("%s: unexpected validation errors: %s", tc.name, diff.ObjectDiff(e, a))
}
}
}
// checkRequest verifies that the request does not exceed any quota constraint. it returns back a copy of quotas not yet persisted
// that capture what the usage would be if the request succeeded. It return an error if the is insufficient quota to satisfy the request
func (e *quotaEvaluator) checkRequest(quotas []api.ResourceQuota, a admission.Attributes) ([]api.ResourceQuota, error) {
namespace := a.GetNamespace()
evaluators := e.registry.Evaluators()
evaluator, found := evaluators[a.GetKind().GroupKind()]
if !found {
return quotas, nil
}
op := a.GetOperation()
operationResources := evaluator.OperationResources(op)
if len(operationResources) == 0 {
return quotas, nil
}
// find the set of quotas that are pertinent to this request
// reject if we match the quota, but usage is not calculated yet
// reject if the input object does not satisfy quota constraints
// if there are no pertinent quotas, we can just return
inputObject := a.GetObject()
interestingQuotaIndexes := []int{}
for i := range quotas {
resourceQuota := quotas[i]
match := evaluator.Matches(&resourceQuota, inputObject)
if !match {
continue
}
hardResources := quota.ResourceNames(resourceQuota.Status.Hard)
evaluatorResources := evaluator.MatchesResources()
requiredResources := quota.Intersection(hardResources, evaluatorResources)
err := evaluator.Constraints(requiredResources, inputObject)
if err != nil {
return nil, admission.NewForbidden(a, fmt.Errorf("Failed quota: %s: %v", resourceQuota.Name, err))
}
if !hasUsageStats(&resourceQuota) {
return nil, admission.NewForbidden(a, fmt.Errorf("Status unknown for quota: %s", resourceQuota.Name))
}
interestingQuotaIndexes = append(interestingQuotaIndexes, i)
}
if len(interestingQuotaIndexes) == 0 {
return quotas, nil
}
// Usage of some resources cannot be counted in isolation. For example when
// the resource represents a number of unique references to external
// resource. In such a case an evaluator needs to process other objects in
// the same namespace which needs to be known.
if accessor, err := meta.Accessor(inputObject); namespace != "" && err == nil {
if accessor.GetNamespace() == "" {
accessor.SetNamespace(namespace)
}
}
// there is at least one quota that definitely matches our object
// as a result, we need to measure the usage of this object for quota
// on updates, we need to subtract the previous measured usage
// if usage shows no change, just return since it has no impact on quota
deltaUsage := evaluator.Usage(inputObject)
if admission.Update == op {
prevItem := a.GetOldObject()
if prevItem == nil {
return nil, admission.NewForbidden(a, fmt.Errorf("Unable to get previous usage since prior version of object was not found"))
}
// if we can definitively determine that this is not a case of "create on update",
// then charge based on the delta. Otherwise, bill the maximum
metadata, err := meta.Accessor(prevItem)
if err == nil && len(metadata.GetResourceVersion()) > 0 {
prevUsage := evaluator.Usage(prevItem)
deltaUsage = quota.Subtract(deltaUsage, prevUsage)
}
}
if quota.IsZero(deltaUsage) {
return quotas, nil
}
for _, index := range interestingQuotaIndexes {
resourceQuota := quotas[index]
hardResources := quota.ResourceNames(resourceQuota.Status.Hard)
requestedUsage := quota.Mask(deltaUsage, hardResources)
newUsage := quota.Add(resourceQuota.Status.Used, requestedUsage)
maskedNewUsage := quota.Mask(newUsage, quota.ResourceNames(requestedUsage))
if allowed, exceeded := quota.LessThanOrEqual(maskedNewUsage, resourceQuota.Status.Hard); !allowed {
failedRequestedUsage := quota.Mask(requestedUsage, exceeded)
failedUsed := quota.Mask(resourceQuota.Status.Used, exceeded)
failedHard := quota.Mask(resourceQuota.Status.Hard, exceeded)
return nil, admission.NewForbidden(a,
fmt.Errorf("Exceeded quota: %s, requested: %s, used: %s, limited: %s",
resourceQuota.Name,
prettyPrint(failedRequestedUsage),
prettyPrint(failedUsed),
prettyPrint(failedHard)))
}
// update to the new usage number
quotas[index].Status.Used = newUsage
}
return quotas, nil
}
// Admit makes admission decisions while enforcing quota
func (q *quotaAdmission) Admit(a admission.Attributes) (err error) {
// ignore all operations that correspond to sub-resource actions
if a.GetSubresource() != "" {
return nil
}
// if we do not know how to evaluate use for this kind, just ignore
evaluators := q.registry.Evaluators()
evaluator, found := evaluators[a.GetKind()]
if !found {
return nil
}
// for this kind, check if the operation could mutate any quota resources
// if no resources tracked by quota are impacted, then just return
op := a.GetOperation()
operationResources := evaluator.OperationResources(op)
if len(operationResources) == 0 {
return nil
}
// determine if there are any quotas in this namespace
// if there are no quotas, we don't need to do anything
namespace, name := a.GetNamespace(), a.GetName()
items, err := q.indexer.Index("namespace", &api.ResourceQuota{ObjectMeta: api.ObjectMeta{Namespace: namespace, Name: ""}})
if err != nil {
return admission.NewForbidden(a, fmt.Errorf("Error resolving quota."))
}
// if there are no items held in our indexer, check our live-lookup LRU, if that misses, do the live lookup to prime it.
if len(items) == 0 {
lruItemObj, ok := q.liveLookupCache.Get(a.GetNamespace())
if !ok || lruItemObj.(liveLookupEntry).expiry.Before(time.Now()) {
// TODO: If there are multiple operations at the same time and cache has just expired,
// this may cause multiple List operations being issued at the same time.
// If there is already in-flight List() for a given namespace, we should wait until
// it is finished and cache is updated instead of doing the same, also to avoid
// throttling - see #22422 for details.
liveList, err := q.client.Core().ResourceQuotas(namespace).List(api.ListOptions{})
if err != nil {
return admission.NewForbidden(a, err)
}
newEntry := liveLookupEntry{expiry: time.Now().Add(q.liveTTL)}
for i := range liveList.Items {
newEntry.items = append(newEntry.items, &liveList.Items[i])
}
q.liveLookupCache.Add(a.GetNamespace(), newEntry)
lruItemObj = newEntry
}
lruEntry := lruItemObj.(liveLookupEntry)
for i := range lruEntry.items {
items = append(items, lruEntry.items[i])
}
}
// if there are still no items, we can return
if len(items) == 0 {
return nil
}
// find the set of quotas that are pertinent to this request
// reject if we match the quota, but usage is not calculated yet
// reject if the input object does not satisfy quota constraints
// if there are no pertinent quotas, we can just return
inputObject := a.GetObject()
resourceQuotas := []*api.ResourceQuota{}
for i := range items {
resourceQuota := items[i].(*api.ResourceQuota)
match := evaluator.Matches(resourceQuota, inputObject)
if !match {
continue
}
hardResources := quota.ResourceNames(resourceQuota.Status.Hard)
evaluatorResources := evaluator.MatchesResources()
requiredResources := quota.Intersection(hardResources, evaluatorResources)
err := evaluator.Constraints(requiredResources, inputObject)
if err != nil {
return admission.NewForbidden(a, fmt.Errorf("Failed quota: %s: %v", resourceQuota.Name, err))
}
if !hasUsageStats(resourceQuota) {
return admission.NewForbidden(a, fmt.Errorf("Status unknown for quota: %s", resourceQuota.Name))
}
resourceQuotas = append(resourceQuotas, resourceQuota)
}
if len(resourceQuotas) == 0 {
return nil
}
// there is at least one quota that definitely matches our object
// as a result, we need to measure the usage of this object for quota
// on updates, we need to subtract the previous measured usage
// if usage shows no change, just return since it has no impact on quota
deltaUsage := evaluator.Usage(inputObject)
if admission.Update == op {
prevItem, err := evaluator.Get(namespace, name)
if err != nil {
return admission.NewForbidden(a, fmt.Errorf("Unable to get previous: %v", err))
}
prevUsage := evaluator.Usage(prevItem)
deltaUsage = quota.Subtract(deltaUsage, prevUsage)
}
if quota.IsZero(deltaUsage) {
return nil
}
// TODO: Move to a bucketing work queue
// If we guaranteed that we processed the request in order it was received to server, we would reduce quota conflicts.
// Until we have the bucketing work queue, we jitter requests and retry on conflict.
numRetries := 10
interval := time.Duration(rand.Int63n(90)+int64(10)) * time.Millisecond
// seed the retry loop with the initial set of quotas to process (should reduce each iteration)
resourceQuotasToProcess := resourceQuotas
for retry := 1; retry <= numRetries; retry++ {
// the list of quotas we will try again if there is a version conflict
tryAgain := []*api.ResourceQuota{}
// check that we pass all remaining quotas so we do not prematurely charge
// for each quota, mask the usage to the set of resources tracked by the quota
// if request + used > hard, return an error describing the failure
updatedUsage := map[string]api.ResourceList{}
for _, resourceQuota := range resourceQuotasToProcess {
hardResources := quota.ResourceNames(resourceQuota.Status.Hard)
requestedUsage := quota.Mask(deltaUsage, hardResources)
newUsage := quota.Add(resourceQuota.Status.Used, requestedUsage)
if allowed, exceeded := quota.LessThanOrEqual(newUsage, resourceQuota.Status.Hard); !allowed {
failedRequestedUsage := quota.Mask(requestedUsage, exceeded)
failedUsed := quota.Mask(resourceQuota.Status.Used, exceeded)
failedHard := quota.Mask(resourceQuota.Status.Hard, exceeded)
return admission.NewForbidden(a,
fmt.Errorf("Exceeded quota: %s, requested: %s, used: %s, limited: %s",
resourceQuota.Name,
prettyPrint(failedRequestedUsage),
prettyPrint(failedUsed),
prettyPrint(failedHard)))
}
updatedUsage[resourceQuota.Name] = newUsage
}
// update the status for each quota with its new usage
// if we get a conflict, get updated quota, and enqueue
for i, resourceQuota := range resourceQuotasToProcess {
newUsage := updatedUsage[resourceQuota.Name]
quotaToUpdate := &api.ResourceQuota{
ObjectMeta: api.ObjectMeta{
Name: resourceQuota.Name,
Namespace: resourceQuota.Namespace,
ResourceVersion: resourceQuota.ResourceVersion,
},
Status: api.ResourceQuotaStatus{
Hard: quota.Add(api.ResourceList{}, resourceQuota.Status.Hard),
Used: newUsage,
},
}
_, err = q.client.Core().ResourceQuotas(quotaToUpdate.Namespace).UpdateStatus(quotaToUpdate)
if err != nil {
if !errors.IsConflict(err) {
return admission.NewForbidden(a, fmt.Errorf("Unable to update quota status: %s %v", resourceQuota.Name, err))
}
// if we get a conflict, we get the latest copy of the quota documents that were not yet modified so we retry all with latest state.
for fetchIndex := i; fetchIndex < len(resourceQuotasToProcess); fetchIndex++ {
latestQuota, err := q.client.Core().ResourceQuotas(namespace).Get(resourceQuotasToProcess[fetchIndex].Name)
if err != nil {
return admission.NewForbidden(a, fmt.Errorf("Unable to get quota: %s %v", resourceQuotasToProcess[fetchIndex].Name, err))
}
tryAgain = append(tryAgain, latestQuota)
}
break
}
}
// all quotas were updated, so we can return
if len(tryAgain) == 0 {
return nil
}
// we have concurrent requests to update quota, so look to retry if needed
// next iteration, we need to process the items that have to try again
// pause the specified interval to encourage jitter
if retry == numRetries {
names := []string{}
for _, quota := range tryAgain {
names = append(names, quota.Name)
}
return admission.NewForbidden(a, fmt.Errorf("Unable to update status for quota: %s, ", strings.Join(names, ",")))
}
resourceQuotasToProcess = tryAgain
time.Sleep(interval)
}
return nil
}
