Use CIS Google Kubernetes Engine Benchmark v1.5.0 policy constraints

Policy Controller comes with a default library of constraint templates that can be used with the Center for Internet Security (CIS) GKE v1.5.0 policy bundle to help audit the compliance of your GKE on Google Cloud cluster against the CIS Google Kubernetes Engine (GKE) Benchmarks v1.5.0. This benchmark is a set of recommended security controls for configuring GKE.

This page contains instructions for manually applying a policy bundle. Alternatively, you can apply policy bundles directly.

Warning: After you choose a method to apply policy bundles (manual, gcloud CLI, or Google Cloud console), using a different method to install policy bundles can cause errors in your environment.

This page is for IT administrators and Operators who want to ensure that all resources running within the cloud platform meet organizational compliance requirements by providing and maintaining automation to audit or enforce. To learn more about common roles and example tasks that we reference in Google Cloud content, see Common GKE Enterprise user roles and tasks.

This bundle of constraints includes controls in the following domains:

• RBAC and service accounts
• Pod Security Policies
• Network policies and CNI
• Secrets management
• Extensible Admission Control
• General policies
• Managed Services

Note: This bundle has not been certified by CIS.

CIS GKE v1.5.0 policy bundle constraints

Constraint Name	Constraint Description	Control IDs
cis-gke-v1.5.0-apparmor	Restricts the AppArmor profile for Pods.	4.2.1
cis-gke-v1.5.0-restrict-creation-with-default-serviceaccount	Restrict resource creation using a default ServiceAccount.	4.1.5
cis-gke-v1.5.0-restrict-loadbalancer	Disallows all services with type LoadBalancer.	5.6.8
cis-gke-v1.5.0-restrict-secrets-of-type-basic-auth	Restricts the use of basic-auth type secrets.	4.4.2
cis-gke-v1.5.0-require-binauthz	Requires the Binary Authorization Validating Admission Webhook.	4.5.1, 5.10.4
cis-gke-v1.5.0-require-cos-node-image	Requires Container-Optimized OS as the node OS image.	5.5.1
cis-gke-v1.5.0-require-gke-metadata-server-enabled	Requires the GKE Metadata Service is enabled on each node in the cluster.	5.4.2
cis-gke-v1.5.0-require-ingress.class-gce	Requires that all Ingress objects have a kubernetes.io/ingress.class: gce annotation.	5.6.8
cis-gke-v1.5.0-require-managed-certificates	Requires that all Ingress objects have a networking.gke.io/managed-certificates annotation.	5.6.8
cis-gke-v1.5.0-require-namespace-networkpolicy	Requires that every Namespace defined in the cluster has a NetworkPolicy.	4.3.2
cis-gke-v1.5.0-require-seccomp-default	Containers cannot run with a seccomp profile other than runtime/default.	4.6.2
cis-gke-v1.5.0-require-securitycontext	Requires that pods define securityContext.	4.6.3
cis-gke-v1.5.0-capabilities	Adding capabilities beyond those listed is not allowed.	4.2.1
cis-gke-v1.5.0-restrict-cluster-admin-role	Restricts the use of the cluster-admin role.	4.1.1
cis-gke-v1.5.0-restrict-default-namespace	Restricts pods from using the default Namespace.	4.6.1, 4.6.4
cis-gke-v1.5.0-restrict-env-var-secrets	Restricts the use of secrets as environment variables in container definitions.	4.4.1
cis-gke-v1.5.0-host-namespace	Restricts containers with hostPID or hostIPC set to true.	4.2.1
cis-gke-v1.5.0-restrict-pods-create	Restricts the creation of pods in Roles and ClusterRoles.	4.1.4
cis-gke-v1.5.0-restrict-privileged-containers	Restricts containers with securityContext.privileged set to true.	4.2.1
cis-gke-v1.5.0-restrict-rbac-subjects	Restricts the use of names in RBAC subjects to permitted values.	5.8.2
cis-gke-v1.5.0-restrict-role-wildcards	Restricts the use of wildcards in Roles and ClusterRoles.	4.1.3
cis-gke-v1.5.0-restrict-role-secrets	Restricts the use of secrets in Roles and ClusterRoles.	4.1.2
cis-gke-v1.5.0-restrict-automountserviceaccounttoken	Restricts the use of service account tokens for pods.	4.1.5, 4.1.6
cis-gke-v1.5.0-selinux	Cannot set the SELinux type or set a custom SELinux user or role option.	4.2.1
cis-gke-v1.5.0-host-port	HostPorts should be disallowed.	4.2.1
cis-gke-v1.5.0-hostpath-volumes	HostPath volumes must be forbidden.	4.2.1
cis-gke-v1.5.0-hostprocess	Containers and pods cannot run with securityContext.windowsOptions.hostProcess set to true.	4.2.1
cis-gke-v1.5.0-proc-mount-type	Containers cannot run with a procMount set to a value other than Default.	4.2.1
cis-gke-v1.5.0-restrict-bind-escalate-impersonate	Restricts the access to the bind, escalate, impersonate on roles/clusterroles in Roles and ClusterRoles.	4.1.8
cis-gke-v1.5.0-restrict-certificatesigningrequests-approval	The approval of the client certificates is restricted.	4.1.11
cis-gke-v1.5.0-restrict-nodes-proxy	Restricts the access to the proxy sub-resource of nodes in Roles and ClusterRoles.	4.1.10
cis-gke-v1.5.0-restrict-persistent-volume	Restricts the creation of persistentvolumes in Roles and ClusterRoles.	4.1.9
cis-gke-v1.5.0-restrict-serviceaccounts-token	Restricts the creation of serviceaccount tokens in Roles and ClusterRoles.	4.1.13
cis-gke-v1.5.0-restrict-system-masters-group	Disallows the use of system:masters group.	5.1.7
cis-gke-v1.5.0-restrict-system-masters-group	Restricts the access to webhook configuration objects in Roles and ClusterRoles.	4.1.12
cis-gke-v1.5.0-seccomp	Seccomp profile must not be set to Unconfined.	4.2.1
cis-gke-v1.5.0-sysctls	Containers can set only sysctls listed in the allowedSysctls field.	4.2.1
cis-gke-v1.5.0-host-namespaces-hostnetwork	Host namespaces hostNetwork can only be false.	4.2.1

Before you begin

Caution: This policy bundle is intended for use only with GKE on Google Cloud. For other GKE clusters, the CIS Kubernetes Benchmarks policy bundle is recommended.

1. Install and initialize the Google Cloud CLI, which provides the gcloud and kubectl commands used in these instructions. If you use Cloud Shell, Google Cloud CLI comes pre-installed.
2. Install Policy Controller v1.16.2 or higher on your cluster with the default library of constraint templates. You must also enable support for referential constraints, as this bundle contains referential constraints.

Configure for referential constraints

Warning: You can overwrite your changes. If you already have an existing Config in the gatekeeper-system namespace, you must include all previous customization settings to preserve your changes.

1. Save the following YAML manifest to a file as policycontroller-config.yaml. The manifest configures Policy Controller to watch specific kinds of objects.

   apiVersion: config.gatekeeper.sh/v1alpha1
   kind: Config
   metadata:
     name: config
     namespace: "gatekeeper-system"
   spec:
     sync:
       syncOnly:
         - group: "admissionregistration.k8s.io"
           version: "v1"
           kind: "ValidatingWebhookConfiguration"
         - group: "networking.k8s.io"
           version: "v1"
           kind: "NetworkPolicy"
   

2. Apply the policycontroller-config.yaml manifest:

   kubectl apply -f policycontroller-config.yaml
   

Configure your cluster and workload

1. Enablement and configuration of Google Groups for RBAC is required in cis-gke-v1.5.0-restrict-rbac-subjects.
2. Enablement and configuration of Binary Authorization is required in cis-gke-v1.5.0-require-binauthz.

Audit policies

Policy Controller lets you enforce policies for your Kubernetes cluster. To help test your workloads and their compliance with regard to the CIS GKE v1.5.0 policies outlined in the preceding table, you can deploy these constraints in "audit" mode to reveal and address violations.

You can apply these policies with spec.enforcementAction set to dryrun using kubectl, kpt, or Config Sync.

kubectl

1. (Optional) Preview the policy constraints with kubectl:

   kubectl kustomize https://github.com/GoogleCloudPlatform/gke-policy-library.git/anthos-bundles/cis-gke-v1.5.0
   

2. Apply the policy constraints with kubectl:

   kubectl apply -k https://github.com/GoogleCloudPlatform/gke-policy-library.git/anthos-bundles/cis-gke-v1.5.0
   

   The output is the following:

   k8savoiduseofsystemmastersgroup.constraints.gatekeeper.sh/cis-gke-v1.5.0-restrict-system-masters-group created
   k8sblockcreationwithdefaultserviceaccount.constraints.gatekeeper.sh/cis-gke-v1.5.0-restrict-creation-with-default-serviceaccount created
   k8sblockloadbalancer.constraints.gatekeeper.sh/cis-gke-v1.5.0-restrict-loadbalancer created
   k8sblockobjectsoftype.constraints.gatekeeper.sh/cis-gke-v1.5.0-restrict-secrets-of-type-basic-auth created
   k8snoenvvarsecrets.constraints.gatekeeper.sh/cis-gke-v1.5.0-restrict-env-var-secrets created
   k8spspapparmor.constraints.gatekeeper.sh/cis-gke-v1.5.0-apparmor created
   k8spspcapabilities.constraints.gatekeeper.sh/cis-gke-v1.5.0-capabilities created
   k8spspforbiddensysctls.constraints.gatekeeper.sh/cis-gke-v1.5.0-sysctls created
   k8spsphostfilesystem.constraints.gatekeeper.sh/cis-gke-v1.5.0-hostpath-volumes created
   k8spsphostnamespace.constraints.gatekeeper.sh/cis-gke-v1.5.0-host-namespace created
   k8spsphostnetworkingports.constraints.gatekeeper.sh/cis-gke-v1.5.0-host-port created
   k8spspprivilegedcontainer.constraints.gatekeeper.sh/cis-gke-v1.5.0-privileged-containers created
   k8spspprocmount.constraints.gatekeeper.sh/cis-gke-v1.5.0-proc-mount-type created
   k8spspselinuxv2.constraints.gatekeeper.sh/cis-gke-v1.5.0-selinux created
   k8spspseccomp.constraints.gatekeeper.sh/cis-gke-v1.5.0-require-seccomp-default created
   k8spspseccomp.constraints.gatekeeper.sh/cis-gke-v1.5.0-seccomp created
   k8spspwindowshostprocess.constraints.gatekeeper.sh/cis-gke-v1.5.0-hostprocess created
   k8spodsrequiresecuritycontext.constraints.gatekeeper.sh/cis-gke-v1.5.0-require-securitycontext created
   k8sprohibitrolewildcardaccess.constraints.gatekeeper.sh/cis-gke-v1.5.0-restrict-role-wildcards created
   k8srequirebinauthz.constraints.gatekeeper.sh/cis-gke-v1.5.0-require-binauthz created
   k8srequirecosnodeimage.constraints.gatekeeper.sh/cis-gke-v1.5.0-require-cos-node-image created
   k8srequirenamespacenetworkpolicies.constraints.gatekeeper.sh/cis-gke-v1.5.0-require-namespace-networkpolicy created
   k8srequiredannotations.constraints.gatekeeper.sh/cis-gke-v1.5.0-require-ingress.class-gce created
   k8srequiredannotations.constraints.gatekeeper.sh/cis-gke-v1.5.0-require-managed-certificates created
   k8srequiredlabels.constraints.gatekeeper.sh/cis-gke-v1.5.0-require-gke-metadata-server-enabled created
   k8srestrictautomountserviceaccounttokens.constraints.gatekeeper.sh/cis-gke-v1.5.0-restrict-automountserviceaccounttoken created
   k8srestrictnamespaces.constraints.gatekeeper.sh/cis-gke-v1.5.0-restrict-default-namespace created
   k8srestrictrbacsubjects.constraints.gatekeeper.sh/cis-gke-v1.5.0-restrict-rbac-subjects created
   k8srestrictrolebindings.constraints.gatekeeper.sh/cis-gke-v1.5.0-restrict-cluster-admin-role created
   k8srestrictrolerules.constraints.gatekeeper.sh/cis-gke-v1.5.0-restrict-bind-escalate-impersonate created
   k8srestrictrolerules.constraints.gatekeeper.sh/cis-gke-v1.5.0-restrict-certificatesigningrequests-approval created
   k8srestrictrolerules.constraints.gatekeeper.sh/cis-gke-v1.5.0-restrict-nodes-proxy created
   k8srestrictrolerules.constraints.gatekeeper.sh/cis-gke-v1.5.0-restrict-persistent-volume created
   k8srestrictrolerules.constraints.gatekeeper.sh/cis-gke-v1.5.0-restrict-pods-create created
   k8srestrictrolerules.constraints.gatekeeper.sh/cis-gke-v1.5.0-restrict-role-secrets created
   k8srestrictrolerules.constraints.gatekeeper.sh/cis-gke-v1.5.0-restrict-serviceaccounts-token created
   k8srestrictrolerules.constraints.gatekeeper.sh/cis-gke-v1.5.0-restrict-webhook-config created
   

3. Verify that policy constraints have been installed and check if violations exist across the cluster:

   kubectl get constraints -l policycontroller.gke.io/bundleName=cis-gke-v1.5.0
   

   The output is similar to the following:

   NAME                                                                                                     ENFORCEMENT-ACTION   TOTAL-VIOLATIONS
   k8savoiduseofsystemmastersgroup.constraints.gatekeeper.sh/cis-gke-v1.5.0-restrict-system-masters-group   dryrun               0
   
   NAME                                                                                                                               ENFORCEMENT-ACTION   TOTAL-VIOLATIONS
   k8sblockcreationwithdefaultserviceaccount.constraints.gatekeeper.sh/cis-gke-v1.5.0-restrict-creation-with-default-serviceaccount   dryrun               0
   
   NAME                                                                                  ENFORCEMENT-ACTION   TOTAL-VIOLATIONS
   k8sblockloadbalancer.constraints.gatekeeper.sh/cis-gke-v1.5.0-restrict-loadbalancer   dryrun               0
   
   NAME                                                                                                 ENFORCEMENT-ACTION   TOTAL-VIOLATIONS
   k8sblockobjectsoftype.constraints.gatekeeper.sh/cis-gke-v1.5.0-restrict-secrets-of-type-basic-auth   dryrun               0
   
   NAME                                                                                   ENFORCEMENT-ACTION   TOTAL-VIOLATIONS
   k8snoenvvarsecrets.constraints.gatekeeper.sh/cis-gke-v1.5.0-restrict-env-var-secrets   dryrun               0
   
   NAME                                                                                             ENFORCEMENT-ACTION   TOTAL-VIOLATIONS
   k8spodsrequiresecuritycontext.constraints.gatekeeper.sh/cis-gke-v1.5.0-require-securitycontext   dryrun               0
   
   NAME                                                                                             ENFORCEMENT-ACTION   TOTAL-VIOLATIONS
   k8sprohibitrolewildcardaccess.constraints.gatekeeper.sh/cis-gke-v1.5.0-restrict-role-wildcards   dryrun               0
   
   NAME                                                               ENFORCEMENT-ACTION   TOTAL-VIOLATIONS
   k8spspapparmor.constraints.gatekeeper.sh/cis-gke-v1.5.0-apparmor   dryrun               0
   
   NAME                                                                       ENFORCEMENT-ACTION   TOTAL-VIOLATIONS
   k8spspcapabilities.constraints.gatekeeper.sh/cis-gke-v1.5.0-capabilities   dryrun               0
   
   NAME                                                                      ENFORCEMENT-ACTION   TOTAL-VIOLATIONS
   k8spspforbiddensysctls.constraints.gatekeeper.sh/cis-gke-v1.5.0-sysctls   dryrun               0
   
   NAME                                                                             ENFORCEMENT-ACTION   TOTAL-VIOLATIONS
   k8spsphostfilesystem.constraints.gatekeeper.sh/cis-gke-v1.5.0-hostpath-volumes   dryrun               0
   
   NAME                                                                          ENFORCEMENT-ACTION   TOTAL-VIOLATIONS
   k8spsphostnamespace.constraints.gatekeeper.sh/cis-gke-v1.5.0-host-namespace   dryrun               0
   
   NAME                                                                           ENFORCEMENT-ACTION   TOTAL-VIOLATIONS
   k8spsphostnetworkingports.constraints.gatekeeper.sh/cis-gke-v1.5.0-host-port   dryrun               0
   
   NAME                                                                                       ENFORCEMENT-ACTION   TOTAL-VIOLATIONS
   k8spspprivilegedcontainer.constraints.gatekeeper.sh/cis-gke-v1.5.0-privileged-containers   dryrun               0
   
   NAME                                                                       ENFORCEMENT-ACTION   TOTAL-VIOLATIONS
   k8spspprocmount.constraints.gatekeeper.sh/cis-gke-v1.5.0-proc-mount-type   dryrun               0
   
   NAME                                                                             ENFORCEMENT-ACTION   TOTAL-VIOLATIONS
   k8spspseccomp.constraints.gatekeeper.sh/cis-gke-v1.5.0-require-seccomp-default   dryrun               0
   k8spspseccomp.constraints.gatekeeper.sh/cis-gke-v1.5.0-seccomp                   dryrun               0
   
   NAME                                                               ENFORCEMENT-ACTION   TOTAL-VIOLATIONS
   k8spspselinuxv2.constraints.gatekeeper.sh/cis-gke-v1.5.0-selinux   dryrun               0
   
   NAME                                                                            ENFORCEMENT-ACTION   TOTAL-VIOLATIONS
   k8spspwindowshostprocess.constraints.gatekeeper.sh/cis-gke-v1.5.0-hostprocess   dryrun               0
   
   NAME                                                                           ENFORCEMENT-ACTION   TOTAL-VIOLATIONS
   k8srequirebinauthz.constraints.gatekeeper.sh/cis-gke-v1.5.0-require-binauthz   dryrun               0
   
   NAME                                                                                     ENFORCEMENT-ACTION   TOTAL-VIOLATIONS
   k8srequirecosnodeimage.constraints.gatekeeper.sh/cis-gke-v1.5.0-require-cos-node-image   dryrun               0
   
   NAME                                                                                           ENFORCEMENT-ACTION   TOTAL-VIOLATIONS
   k8srequiredannotations.constraints.gatekeeper.sh/cis-gke-v1.5.0-require-ingress.class-gce      dryrun               0
   k8srequiredannotations.constraints.gatekeeper.sh/cis-gke-v1.5.0-require-managed-certificates   dryrun               0
   
   NAME                                                                                             ENFORCEMENT-ACTION   TOTAL-VIOLATIONS
   k8srequiredlabels.constraints.gatekeeper.sh/cis-gke-v1.5.0-require-gke-metadata-server-enabled   dryrun               0
   
   NAME                                                                                                          ENFORCEMENT-ACTION   TOTAL-VIOLATIONS
   k8srequirenamespacenetworkpolicies.constraints.gatekeeper.sh/cis-gke-v1.5.0-require-namespace-networkpolicy   dryrun               0
   
   NAME                                                                                                                      ENFORCEMENT-ACTION   TOTAL-VIOLATIONS
   k8srestrictautomountserviceaccounttokens.constraints.gatekeeper.sh/cis-gke-v1.5.0-restrict-automountserviceaccounttoken   dryrun               0
   
   NAME                                                                                        ENFORCEMENT-ACTION   TOTAL-VIOLATIONS
   k8srestrictnamespaces.constraints.gatekeeper.sh/cis-gke-v1.5.0-restrict-default-namespace   dryrun               0
   
   NAME                                                                                      ENFORCEMENT-ACTION   TOTAL-VIOLATIONS
   k8srestrictrbacsubjects.constraints.gatekeeper.sh/cis-gke-v1.5.0-restrict-rbac-subjects   dryrun               0
   
   NAME                                                                                           ENFORCEMENT-ACTION   TOTAL-VIOLATIONS
   k8srestrictrolebindings.constraints.gatekeeper.sh/cis-gke-v1.5.0-restrict-cluster-admin-role   dryrun               0
   
   NAME                                                                                                         ENFORCEMENT-ACTION   TOTAL-VIOLATIONS
   k8srestrictrolerules.constraints.gatekeeper.sh/cis-gke-v1.5.0-restrict-bind-escalate-impersonate             dryrun               0
   k8srestrictrolerules.constraints.gatekeeper.sh/cis-gke-v1.5.0-restrict-certificatesigningrequests-approval   dryrun               0
   k8srestrictrolerules.constraints.gatekeeper.sh/cis-gke-v1.5.0-restrict-nodes-proxy                           dryrun               0
   k8srestrictrolerules.constraints.gatekeeper.sh/cis-gke-v1.5.0-restrict-persistent-volume                     dryrun               0
   k8srestrictrolerules.constraints.gatekeeper.sh/cis-gke-v1.5.0-restrict-pods-create                           dryrun               0
   k8srestrictrolerules.constraints.gatekeeper.sh/cis-gke-v1.5.0-restrict-role-secrets                          dryrun               0
   k8srestrictrolerules.constraints.gatekeeper.sh/cis-gke-v1.5.0-restrict-serviceaccounts-token                 dryrun               0
   k8srestrictrolerules.constraints.gatekeeper.sh/cis-gke-v1.5.0-restrict-webhook-config                        dryrun               0
   

kpt

1. Install and setup kpt. kpt is used in these instructions to customize and deploy Kubernetes resources.

2. Download the CIS policy bundle from GitHub using kpt:

   kpt pkg get https://github.com/GoogleCloudPlatform/gke-policy-library.git/anthos-bundles/cis-gke-v1.5.0
   

3. Run the set-enforcement-action kpt function to set the policies' enforcement action to dryrun:

   kpt fn eval cis-gke-v1.5.0 -i gcr.io/kpt-fn/set-enforcement-action:v0.1 \
     -- enforcementAction=dryrun
   

4. Initialize the working directory with kpt, which creates a resource to track changes:

   cd cis-gke-v1.5.0
   kpt live init
   

5. Apply the policy constraints with kpt:

   kpt live apply
   

6. Verify that policy constraints have been installed and check if violations exist across the cluster:

   kpt live status --output table --poll-until current
   

   A status of CURRENT confirms successful installation of the constraints.

Config Sync

1. Install and setup kpt. kpt is used in these instructions to customize and deploy Kubernetes resources.

Operators using Config Sync to deploy policies to their clusters can use the following instructions:

1. Change into the sync directory for Config Sync:

   cd SYNC_ROOT_DIR
   

   Caution: Kpt v1.0.0-beta.17 and later automatically create a resourcegroup.yaml file during live init which shouldn't be checked into your Config Sync repository. If not already present, add resourcegroup.yaml to your repository's .gitignore file.

   To create or append .gitignore with resourcegroup.yaml:

   echo resourcegroup.yaml >> .gitignore
   

2. Create a dedicated policies directory:

   mkdir -p policies
   

3. Download the CIS GKE v1.5.0 policy bundle from GitHub using kpt:

   kpt pkg get https://github.com/GoogleCloudPlatform/gke-policy-library.git/anthos-bundles/cis-gke-v1.5.0 policies/cis-gke-v1.5.0
   

4. Run the set-enforcement-action kpt function to set the policies' enforcement action to dryrun:

   kpt fn eval policies/cis-gke-v1.5.0 -i gcr.io/kpt-fn/set-enforcement-action:v0.1 -- enforcementAction=dryrun
   

5. (Optional) Preview the policy constraints to be created:

   kpt live init policies/cis-gke-v1.5.0
   kpt live apply --dry-run policies/cis-gke-v1.5.0
   

6. If your sync directory for Config Sync uses Kustomize, add policies/cis-gke-v1.5.0 to your root kustomization.yaml. Otherwise remove the policies/cis-gke-v1.5.0/kustomization.yaml file:

   rm SYNC_ROOT_DIR/policies/cis-gke-v1.5.0/kustomization.yaml
   

7. Push changes to the Config Sync repository:

   git add SYNC_ROOT_DIR/policies/cis-gke-v1.5.0
   git commit -m 'Adding CIS GKE v1.5.0 policy bundle'
   git push
   

8. Verify the status of the installation:

   watch gcloud beta container fleet config-management status --project PROJECT_ID
   

   A status of SYNCED confirms the installation of the policies.

View policy violations

Once the policy constraints are installed in audit mode, violations on the cluster can be viewed in the UI using the Policy Controller Dashboard.

You can also use kubectl to view violations on the cluster using the following command:

kubectl get constraint -l policycontroller.gke.io/bundleName=cis-gke-v1.5.0 -o json | jq -cC '.items[]| [.metadata.name,.status.totalViolations]'

If violations are present, a listing of the violation messages per constraint can be viewed with:

kubectl get constraint -l policycontroller.gke.io/bundleName=cis-gke-v1.5.0 -o json | jq -C '.items[]| select(.status.totalViolations>0)| [.metadata.name,.status.violations[]?]'

Change CIS GKE v1.5.0 policy bundle enforcement action

Once you've reviewed policy violations on your cluster, you can consider changing the enforcement mode so the Admission Controller will either warn on or even deny block non-compliant resource from getting applied to the cluster.

Warning: The deny enforcement action should be used with care as it can potentially block required changes resulting in interruption to critical workloads or the cluster. It is strongly recommended that only the warn or dryrun enforcement actions are used on clusters with production workloads, when testing new constraints, or performing migrations such as upgrading platforms. For more information about enforcement actions, see Auditing using constraints.

kubectl

1. Use kubectl to set the policies' enforcement action to warn:

   kubectl get constraint -l policycontroller.gke.io/bundleName=cis-gke-v1.5.0 -o name | xargs -I {} kubectl patch {} --type='json' -p='[{"op":"replace","path":"/spec/enforcementAction","value":"warn"}]'
   

2. Verify that policy constraints enforcement action have been updated:

   kubectl get constraints -l policycontroller.gke.io/bundleName=cis-gke-v1.5.0
   

kpt

1. Run the set-enforcement-action kpt function to set the policies' enforcement action to warn:

   kpt fn eval -i gcr.io/kpt-fn/set-enforcement-action:v0.1 -- enforcementAction=warn
   

2. Apply the policy constraints:

   kpt live apply
   

Config Sync

Operators using Config Sync to deploy policies to their clusters can use the following instructions:

1. Change into the sync directory for Config Sync:

   cd SYNC_ROOT_DIR
   

2. Run the set-enforcement-action kpt function to set the policies' enforcement action to warn:

   kpt fn eval policies/cis-gke-v1.5.0 -i gcr.io/kpt-fn/set-enforcement-action:v0.1 -- enforcementAction=warn
   

3. Push changes to the Config Sync repository:

   git add SYNC_ROOT_DIR/policies/cis-gke-v1.5.0
   git commit -m 'Adding CIS GKE v1.5.0 policy bundle warn enforcement'
   git push
   

4. Verify the status of the installation:

   gcloud alpha anthos config sync repo list --project PROJECT_ID
   

   Your repository showing up in the SYNCED column confirms the installation of the policies.

Test policy enforcement

Create a non-compliant resource on the cluster using the following command:

cat <<EOF | kubectl apply -f -
apiVersion: v1
kind: Pod
metadata:
  namespace: default
  name: wp-non-compliant
  labels:
    app: wordpress
spec:
  containers:
    - image: wordpress
      name: wordpress
      ports:
      - containerPort: 80
        name: wordpress
EOF

The admission controller should produce a warning listing out the policy violations that this resource violates, as shown in the following example:

Warning: [cis-gke-v1.5.0-restrict-default-namespace] <default> namespace is restricted
Warning: [cis-gke-v1.5.0-require-seccomp-default] Seccomp profile 'not configured' is not allowed for container 'wordpress'. Found at: no explicit profile found. Allowed profiles: {"RuntimeDefault", "runtime/default"}
Warning: [cis-gke-v1.5.0-require-securitycontext] securityContext must be defined for all Pod containers
pod/wp-non-compliant configured

Remove CIS GKE v1.5.0 policy bundle

If needed, the CIS GKE v1.5.0 policy bundle can be removed from the cluster.

kubectl

Use kubectl to remove the policies:

  kubectl delete constraint -l policycontroller.gke.io/bundleName=cis-gke-v1.5.0
  

kpt

Remove the policies:

  kpt live destroy
  

Config Sync

Operators using Config Sync to deploy policies to their clusters can use the following instructions:

1. Push changes to the Config Sync repository:

   git rm -r SYNC_ROOT_DIR/policies/cis-gke-v1.5.0
   git commit -m 'Removing CIS GKE v1.5.0 policy bundle'
   git push
   

2. Verify the status:

   gcloud alpha anthos config sync repo list --project PROJECT_ID
   

   Your repository showing up in the SYNCED column confirms the removal of the policies.