feat(helm): Allow to configure automountServiceAccountToken

[germanattanasio]

Motivation

The deployment of trust-manager in an AKS cluster raised a high-severity security finding from Azure Defender, recommending the disabling of automounted service account tokens to prevent potential misuse by compromised pods.

This PR addresses the issue by allowing users to disableautomountServiceAccountToken while enabling them to use volumes to access the token. This approach is based on the requirement that trust-manager needs the token to interact with the Kubernetes API.

With the proposed changes, you can deploy the chart using the following configuration:

automountServiceAccountToken: false
serviceAccount:
  automountServiceAccountToken: false
volumes:
- name: serviceaccount-token
  projected:
    defaultMode: 0444
    sources:
    - serviceAccountToken:
        expirationSeconds: 3607
        path: token
    - configMap:
        name: kube-root-ca.crt
        items:
        - key: ca.crt
          path: ca.crt
    - downwardAPI:
        items:
        - path: namespace
          fieldRef:
            apiVersion: v1
            fieldPath: metadata.namespace
volumeMounts:
- mountPath: /var/run/secrets/kubernetes.io/serviceaccount
  name: serviceaccount-token
  readOnly: true

Related to: cert-manager/cert-manager#5254

Changes

• Reuse an existing service account if necessary.
• Configure automountServiceAccountToken for both the pod and the service account.
• Enable defining and mounting volumes in the main container.

---

Signed-off-by: German Attanasio [email protected]

[cert-manager-prow]

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[cert-manager-prow]

Hi @germanattanasio. Thanks for your PR.

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