feat: add support for confidential pods

[arc9693]

What type of PR is this?

/kind feature

What this PR does / why we need it:
Kata-cc is a lightweight VM based runtime for containers. As of now, the azurefile-csi-driver’s persistent storage does not work for kata-cc or confidential pods. The file sharing between host and guest is disabled and therefore the SMB mount on host node does not propagate as expected for the pod.
The proposed changes enable the SMB mount inside the guest VM that wraps the confidential pod.

• to enable Kata Confidential Container mount, you need to specify enableKataCCMount as true in storage class or PV:

apiVersion: storage.k8s.io/v1
kind: StorageClass
metadata:
  name: azurefile-csi
provisioner: file.csi.azure.com
allowVolumeExpansion: true
parameters:
  skuName: Premium_LRS
  enableKataCCMount: "true"
reclaimPolicy: Delete
volumeBindingMode: Immediate
mountOptions:
  - dir_mode=0777
  - file_mode=0777
  - mfsymlinks
  - cache=strict  # https://linux.die.net/man/8/mount.cifs
  - nosharesock  # reduce probability of reconnect race
  - actimeo=30  # reduce latency for metadata-heavy workload
  - nobrl  # disable sending byte range lock requests to the server and for applications which have challenges with posix locks

Which issue(s) this PR fixes:

Fixes #

Requirements:

• uses conventional commit messages
• includes documentation
• adds unit tests
• tested upgrade from previous version

Special notes for your reviewer:

Release note:

none

[linux-foundation-easycla]

The committers listed above are authorized under a signed CLA.

• ✅ login: andyzhangx / name: Andy Zhang (bb47dce, f337f3f, 6e32cc6, 4b070eb, 3ddde6b)
• ✅ login: arc9693 / name: Archana Choudhary (a82e15e, b3dc119)

[k8s-ci-robot]

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[k8s-ci-robot]

Hi @arc9693. Thanks for your PR.

I'm waiting for a kubernetes-sigs 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.

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[andyzhangx]

@arc9693 thanks for the PR, can you sign the cla license first? thx

[sprt]

Thank you @arc9693! I left a few comments 🙂

@andyzhangx Do note this is does NOT implement data or secret confidentiality at this point - this is for unblocking the initial use case where customers want to use non-confidential storage inside confidential pods.

[arc9693]

This is needed as of now, because inside a kata-cc pod, the kata agent (using nix:mount rust crate) performs the CIFS mount and it fails with EHOSTUNREACH, even though a command line mount -t cifs succeeds on the same VM.
Kata-agent mount reference: https://github.com/microsoft/kata-containers/blob/386cab09d8c544097f47c60591b283cff2397439/src/agent/src/mount.rs#L107
nix:mount function reference: https://docs.rs/nix/latest/src/nix/mount/linux.rs.html#104-133

[andyzhangx]

/ok-to-test

[andyzhangx]

/retest

[arc9693]

/retest

[andyzhangx]

could you fix the windows ut failure:

https://github.com/kubernetes-sigs/azurefile-csi-driver/actions/runs/11254288924/job/31298301887?pr=1971

    nodeserver.go:202: Unexpected call to *azurefile.MockDirectVolume.Remove([D:\a\azurefile-csi-driver\azurefile-csi-driver\pkg\azurefile\error_is_likely_target]) at D:/a/azurefile-csi-driver/azurefile-csi-driver/pkg/azurefile/nodeserver.go:202 because: there are no expected calls of the method "Remove" for that receiver
--- FAIL: TestNodeUnpublishVolume (0.00s)

    nodeserver.go:543: Unexpected call to *azurefile.MockDirectVolume.Remove([D:\a\azurefile-csi-driver\azurefile-csi-driver\pkg\azurefile\error_is_likely_target]) at D:/a/azurefile-csi-driver/azurefile-csi-driver/pkg/azurefile/nodeserver.go:543 because: there are no expected calls of the method "Remove" for that receiver
--- FAIL: TestNodeUnstageVolume (0.00s)

[andyzhangx]

/retest

[andyzhangx]

/retest

[andyzhangx]

/retest

[andyzhangx]

/lgtm

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: andyzhangx, arc9693

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