policyDefinitions/Kubernetes/do-not-allow-sharing-of-host-process-id-and-ipc-namespaces-in-a-kubernetes-cluster/template.yaml

apiVersion: templates.gatekeeper.sh/v1beta1
kind: ConstraintTemplate
metadata:
  name: k8sazureblockhostnamespace
spec:
  crd:
    spec:
      names:
        kind: K8sAzureBlockHostNamespace
  targets:
    - target: admission.k8s.gatekeeper.sh
      rego: |
        package k8sazureblockhostnamespace

        violation[{"msg": msg, "details": {}}] {
            input_share_hostnamespace(input.review.object)
            msg := sprintf("Sharing the host namespace is not allowed: %v", [input.review.object.metadata.name])
        }

        input_share_hostnamespace(o) {
            o.spec.hostPID
        }
        input_share_hostnamespace(o) {
            o.spec.hostIPC
        }