Chart: Tighten securityContexts and Pod Security Policies. (#10491)

* Values: Fix docs of `controller.podSecurityContext` & `controller.sysctls`.

* Values: Add missing `controller.containerSecurityContext`.

Already in use, but has never been added to values.

* Values: Fix docs of `defaultBackend.podSecurityContext` & `defaultBackend.containerSecurityContext`.

* Helpers: Rename `controller.containerSecurityContext` to `ingress-nginx.controller.containerSecurityContext`.

Due to alignment with other templates.

* Helpers: Improve `extraModules`.

- Make `command` a multiline list.
- Fix `toYaml` usage.
- Remove `toYaml` where not necessary.

* Helpers: Move `ingress-nginx.defaultBackend.fullname`.

* Helpers: Add `ingress-nginx.defaultBackend.containerSecurityContext`.

Extracts the default backend `securityContext` into a template, as for the controller.

* Controller: Fix indentation of `controller.podSecurityContext` & `controller.sysctls`.

* Controller: Improve `controller.extraModules` & `controller.opentelemetry`.

- Add `controller.extraModules.distroless` & `controller.extraModules.resources`.
- Add `controller.opentelemetry.name` & `controller.opentelemetry.distroless`.
- Align `extraModules` inclusion for `controller.extraModules` & `controller.opentelemetry`.
- Remove redundant whitespaces.

* Controller/PSP: Align indentation.

* Controller/PSP: Remove quotes.

* Controller/PSP: Improve comments.

* Controller/PSP: Reorder fields.

See https://v1-24.docs.kubernetes.io/docs/concepts/security/pod-security-policy.

* Admission Webhooks: Fix indentation of `controller.admissionWebhooks.patch.securityContext`.

* Admission Webhooks/PSP: Align indentation.

* Admission Webhooks/PSP: Reorder fields.

* Admission Webhooks/PSP: Align condition.

* Admission Webhooks/ClusterRole: Align PSP rule.

* Default Backend/PSP: Align indentation.

* Default Backend/PSP: Reorder fields.

See https://v1-24.docs.kubernetes.io/docs/concepts/security/pod-security-policy.

* Values: Tighten `controller.image`.

Due to recent changes, the controller image can be run without privilege escalation:

- https://github.com/kubernetes/ingress-nginx/issues/8499
- https://github.com/kubernetes/ingress-nginx/pull/7449

* Values: Tighten `controller.extraModules.containerSecurityContext`.

* Values: Tighten `controller.opentelemetry.containerSecurityContext`.

* Values: Tighten `controller.admissionWebhooks.*.securityContext`.

Moves the pod `securityContext` to the containers to not interfere with injected containers.

* Values: Tighten `defaultBackend.image`.

charts/ingress-nginx/templates/admission-webhooks/job-patch/clusterrole.yaml

@@ -21,14 +21,13 @@ rules:
       - get
       - update
 {{- if .Values.podSecurityPolicy.enabled }}
-  - apiGroups: ['extensions']
-    resources: ['podsecuritypolicies']
-    verbs:     ['use']
-    resourceNames:
+  - apiGroups:      [{{ template "podSecurityPolicy.apiGroup" . }}]
+    resources:      ['podsecuritypolicies']
+    verbs:          ['use']
     {{- with .Values.controller.admissionWebhooks.existingPsp }}
-    - {{ . }}
+    resourceNames:  [{{ . }}]
     {{- else }}
-    - {{ include "ingress-nginx.admissionWebhooks.fullname" . }}
+    resourceNames:  [{{ include "ingress-nginx.admissionWebhooks.fullname" . }}]
     {{- end }}
 {{- end }}
 {{- end }}