# based on https://kyverno.io/policies/pod-security/baseline/disallow-host-path/disallow-host-path/
apiVersion: kyverno.io/v1
kind: ClusterPolicy
metadata:
  name: disallow-host-path
  annotations:
    policies.kyverno.io/category: Pod Security Standards (Baseline)
    policies.kyverno.io/severity: medium
    policies.kyverno.io/subject: Pod
    policies.kyverno.io/description: >-
      HostPath volumes let pods use host directories and volumes in containers.
      Using host resources can be used to access shared data or escalate privileges
      and should not be allowed.      
spec:
  validationFailureAction: audit
  background: true
  rules:
    - name: host-path
      match:
        resources:
          kinds:
            - Pod
      exclude:
        resources:
          namespaces:
            - calico-system
            - tigera-operator
            - monitoring
      validate:
        message: >-
                    HostPath volumes are forbidden. The fields spec.volumes[*].hostPath must not be set.
        pattern:
          spec:
            =(volumes):
              - X(hostPath): "null"