func (d *denyExec) Admit(a admission.Attributes) (err error) { connectRequest, ok := a.GetObject().(*rest.ConnectRequest) if !ok { return errors.NewBadRequest("a connect request was received, but could not convert the request object.") } // Only handle exec or attach requests on pods if connectRequest.ResourcePath != "pods/exec" && connectRequest.ResourcePath != "pods/attach" { return nil } pod, err := d.client.Pods(a.GetNamespace()).Get(connectRequest.Name) if err != nil { return admission.NewForbidden(a, err) } if d.hostPID && pod.Spec.HostPID { return admission.NewForbidden(a, fmt.Errorf("Cannot exec into or attach to a container using host pid")) } if d.hostIPC && pod.Spec.HostIPC { return admission.NewForbidden(a, fmt.Errorf("Cannot exec into or attach to a container using host ipc")) } if d.privileged && isPrivileged(pod) { return admission.NewForbidden(a, fmt.Errorf("Cannot exec into or attach to a privileged container")) } return nil }
func (ir initialResources) Admit(a admission.Attributes) (err error) { // Ignore all calls to subresources or resources other than pods. if a.GetSubresource() != "" || a.GetResource() != string(api.ResourcePods) { return nil } pod, ok := a.GetObject().(*api.Pod) if !ok { return apierrors.NewBadRequest("Resource was marked with kind Pod but was unable to be converted") } ir.estimateAndFillResourcesIfNotSet(pod) return nil }
// Admit admits resources into cluster that do not violate any defined LimitRange in the namespace func (l *limitRanger) Admit(a admission.Attributes) (err error) { // Ignore all calls to subresources if a.GetSubresource() != "" { return nil } obj := a.GetObject() resource := a.GetResource() name := "Unknown" if obj != nil { name, _ = meta.NewAccessor().Name(obj) if len(name) == 0 { name, _ = meta.NewAccessor().GenerateName(obj) } } key := &api.LimitRange{ ObjectMeta: api.ObjectMeta{ Namespace: a.GetNamespace(), Name: "", }, } items, err := l.indexer.Index("namespace", key) if err != nil { return admission.NewForbidden(a, fmt.Errorf("Unable to %s %s at this time because there was an error enforcing limit ranges", a.GetOperation(), resource)) } if len(items) == 0 { return nil } // ensure it meets each prescribed min/max for i := range items { limitRange := items[i].(*api.LimitRange) err = l.limitFunc(limitRange, a.GetResource(), a.GetObject()) if err != nil { return admission.NewForbidden(a, err) } } return nil }
// Admit will deny any SecurityContext that defines options that were not previously available in the api.Container // struct (Capabilities and Privileged) func (p *plugin) Admit(a admission.Attributes) (err error) { if a.GetResource() != string(api.ResourcePods) { return nil } pod, ok := a.GetObject().(*api.Pod) if !ok { return apierrors.NewBadRequest("Resource was marked with kind Pod but was unable to be converted") } for _, v := range pod.Spec.Containers { if v.SecurityContext != nil { if v.SecurityContext.SELinuxOptions != nil { return apierrors.NewForbidden(a.GetResource(), pod.Name, fmt.Errorf("SecurityContext.SELinuxOptions is forbidden")) } if v.SecurityContext.RunAsUser != nil { return apierrors.NewForbidden(a.GetResource(), pod.Name, fmt.Errorf("SecurityContext.RunAsUser is forbidden")) } } } return nil }
// IncrementUsage updates the supplied ResourceQuotaStatus object based on the incoming operation // Return true if the usage must be recorded prior to admitting the new resource // Return an error if the operation should not pass admission control func IncrementUsage(a admission.Attributes, status *api.ResourceQuotaStatus, client client.Interface) (bool, error) { var errs []error dirty := true set := map[api.ResourceName]bool{} for k := range status.Hard { set[k] = true } obj := a.GetObject() // handle max counts for each kind of resource (pods, services, replicationControllers, etc.) if a.GetOperation() == admission.Create { resourceName := resourceToResourceName[a.GetResource()] hard, hardFound := status.Hard[resourceName] if hardFound { used, usedFound := status.Used[resourceName] if !usedFound { return false, fmt.Errorf("quota usage stats are not yet known, unable to admit resource until an accurate count is completed.") } if used.Value() >= hard.Value() { errs = append(errs, fmt.Errorf("limited to %s %s", hard.String(), resourceName)) dirty = false } else { status.Used[resourceName] = *resource.NewQuantity(used.Value()+int64(1), resource.DecimalSI) } } } if a.GetResource() == "pods" { for _, resourceName := range []api.ResourceName{api.ResourceMemory, api.ResourceCPU} { // ignore tracking the resource if it's not in the quota document if !set[resourceName] { continue } hard, hardFound := status.Hard[resourceName] if !hardFound { continue } // if we do not yet know how much of the current resource is used, we cannot accept any request used, usedFound := status.Used[resourceName] if !usedFound { return false, fmt.Errorf("unable to admit pod until quota usage stats are calculated.") } // the amount of resource being requested, or an error if it does not make a request that is tracked pod := obj.(*api.Pod) delta, err := resourcequotacontroller.PodRequests(pod, resourceName) if err != nil { return false, fmt.Errorf("must make a non-zero request for %s since it is tracked by quota.", resourceName) } // if this operation is an update, we need to find the delta usage from the previous state if a.GetOperation() == admission.Update { oldPod, err := client.Pods(a.GetNamespace()).Get(pod.Name) if err != nil { return false, err } // if the previous version of the resource made a resource request, we need to subtract the old request // from the current to get the actual resource request delta. if the previous version of the pod // made no request on the resource, then we get an err value. we ignore the err value, and delta // will just be equal to the total resource request on the pod since there is nothing to subtract. oldRequest, err := resourcequotacontroller.PodRequests(oldPod, resourceName) if err == nil { err = delta.Sub(*oldRequest) if err != nil { return false, err } } } newUsage := used.Copy() newUsage.Add(*delta) // make the most precise comparison possible newUsageValue := newUsage.Value() hardUsageValue := hard.Value() if newUsageValue <= resource.MaxMilliValue && hardUsageValue <= resource.MaxMilliValue { newUsageValue = newUsage.MilliValue() hardUsageValue = hard.MilliValue() } if newUsageValue > hardUsageValue { errs = append(errs, fmt.Errorf("unable to admit pod without exceeding quota for resource %s: limited to %s but require %s to succeed.", resourceName, hard.String(), newUsage.String())) dirty = false } else { status.Used[resourceName] = *newUsage } } } return dirty, errors.NewAggregate(errs) }
func (s *serviceAccount) Admit(a admission.Attributes) (err error) { if a.GetResource() != string(api.ResourcePods) { return nil } obj := a.GetObject() if obj == nil { return nil } pod, ok := obj.(*api.Pod) if !ok { return nil } // Don't modify the spec of mirror pods. // That makes the kubelet very angry and confused, and it immediately deletes the pod (because the spec doesn't match) // That said, don't allow mirror pods to reference ServiceAccounts or SecretVolumeSources either if _, isMirrorPod := pod.Annotations[kubelet.ConfigMirrorAnnotationKey]; isMirrorPod { if len(pod.Spec.ServiceAccountName) != 0 { return admission.NewForbidden(a, fmt.Errorf("A mirror pod may not reference service accounts")) } for _, volume := range pod.Spec.Volumes { if volume.VolumeSource.Secret != nil { return admission.NewForbidden(a, fmt.Errorf("A mirror pod may not reference secrets")) } } return nil } // Set the default service account if needed if len(pod.Spec.ServiceAccountName) == 0 { pod.Spec.ServiceAccountName = DefaultServiceAccountName } // Ensure the referenced service account exists serviceAccount, err := s.getServiceAccount(a.GetNamespace(), pod.Spec.ServiceAccountName) if err != nil { return admission.NewForbidden(a, fmt.Errorf("Error looking up service account %s/%s: %v", a.GetNamespace(), pod.Spec.ServiceAccountName, err)) } if serviceAccount == nil { // TODO: convert to a ServerTimeout error (or other error that sends a Retry-After header) return admission.NewForbidden(a, fmt.Errorf("service account %s/%s was not found, retry after the service account is created", a.GetNamespace(), pod.Spec.ServiceAccountName)) } if s.LimitSecretReferences { if err := s.limitSecretReferences(serviceAccount, pod); err != nil { return admission.NewForbidden(a, err) } } if s.MountServiceAccountToken { if err := s.mountServiceAccountToken(serviceAccount, pod); err != nil { return admission.NewForbidden(a, err) } } if len(pod.Spec.ImagePullSecrets) == 0 { pod.Spec.ImagePullSecrets = make([]api.LocalObjectReference, len(serviceAccount.ImagePullSecrets)) copy(pod.Spec.ImagePullSecrets, serviceAccount.ImagePullSecrets) } return nil }