Require Run As Non-Root User in CEL

 1apiVersion: kyverno.io/v1
 2kind: ClusterPolicy
 3metadata:
 4  name: require-run-as-non-root-user
 5  annotations:
 6    policies.kyverno.io/title: Require Run As Non-Root User in CEL
 7    policies.kyverno.io/category: Pod Security Standards (Restricted) in CEL
 8    policies.kyverno.io/severity: medium
 9    policies.kyverno.io/subject: Pod
10    policies.kyverno.io/minversion: 1.11.0
11    kyverno.io/kyverno-version: 1.11.0
12    kyverno.io/kubernetes-version: "1.26-1.27"
13    policies.kyverno.io/description: >-
14      Containers must be required to run as non-root users. This policy ensures
15      `runAsUser` is either unset or set to a number greater than zero.
16spec:
17  validationFailureAction: Audit
18  background: true
19  rules:
20    - name: run-as-non-root-user
21      match:
22        any:
23        - resources:
24            kinds:
25              - Pod
26            operations:
27            - CREATE
28            - UPDATE
29      validate:
30        cel:
31          expressions:
32            - expression: >-
33                !has(object.spec.securityContext) ||
34                !has(object.spec.securityContext.runAsUser) ||
35                object.spec.securityContext.runAsUser > 0
36              message: >-
37                Running as root is not allowed. The field spec.securityContext.runAsUser must be unset or
38                set to a number greater than zero.
39
40            - expression: >-
41                object.spec.containers.all(container, !has(container.securityContext) ||
42                !has(container.securityContext.runAsUser) ||
43                container.securityContext.runAsUser > 0)
44              message: >-
45                Running as root is not allowed. The field spec.containers[*].securityContext.runAsUser must be unset or
46                set to a number greater than zero
47
48            - expression: >-
49                !has(object.spec.initContainers) ||
50                object.spec.initContainers.all(container, !has(container.securityContext) ||
51                !has(container.securityContext.runAsUser) ||
52                container.securityContext.runAsUser > 0)
53              message: >-
54                Running as root is not allowed. The field spec.initContainers[*].securityContext.runAsUser must be unset or
55                set to a number greater than zero
56
57            - expression: >-
58                !has(object.spec.ephemeralContainers) ||
59                object.spec.ephemeralContainers.all(container, !has(container.securityContext) ||
60                !has(container.securityContext.runAsUser) ||
61                container.securityContext.runAsUser > 0)
62              message: >-
63                Running as root is not allowed. The field spec.ephemeralContainers[*].securityContext.runAsUser must be unset or
64                set to a number greater than zero