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.

I'm waiting for a cert-manager member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

Once the patch is verified, the new status will be reflected by the ok-to-test label.

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[germanattanasio]

[SgtCoDFish]

/ok-to-test

Hey, thanks for raising this and sorry it took a while to get eyes on it. I've enabled testing and dropped a question too!

[SgtCoDFish]

question: do we need to expose this? I might be missing something, but could we leave this out and just override it at the level of the trust-manager pods? That seems simpler.

If we do need to add this, should it default to false instead?

[germanattanasio]

I wanted it to be backward compatible but It's up to you