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Detailed text description: Attestation flow

This page provides a long description of the attestation flow diagram used in the Attestation and the trustee service article. It shows how a confidential service gets started with the help of the trustee service.

Overview​

Background colors mark trust. Green areas are trusted. Red areas with a dashed border are untrusted. The untrusted infrastructure is on the left. The trusted external infrastructure and the image registry are on the right.

Main components​

  1. Untrusted infrastructure:
  • A red area labeled with the Codesphere platform and hosts.
  • Contains a green confidential micro-VM.
  1. Confidential micro-VM:
  • Runs inside the untrusted infrastructure.
  • Contains a gray attestation agent at the top.
  • Contains the user workload below the attestation agent.
  • All numbered arrows start or end at the attestation agent, except step 5.
  1. Trustee service:
  • Runs on a green area labeled trusted external infrastructure.
  1. Image registry:
  • Positioned below the trustee service, outside both areas.

Steps​

  1. The untrusted infrastructure schedules the micro-VM.
  2. The attestation agent gets a nonce from the trustee service.
  3. The attestation agent generates the attestation report. This step is drawn as an arrow that loops back to the agent.
  4. The attestation agent sends the attestation report to the trustee service.
  5. The trustee service verifies the report. This step is drawn as an arrow that loops back to the trustee service.
  6. The trustee service releases keys and secrets to the attestation agent.
  7. The attestation agent pulls the image from the image registry.
  8. The attestation agent starts the user workload with the image and the secrets.