Re: [PATCH v2 1/3] ipe: add the .ipe policy keyring

[Manuel Huber]

On Wed, Nov 04, 2026 at 12:14:57PM -0800, Fan Wu wrote:
> That way no private key ever needs to live in the guest, and it
> confines the TCB to the VM host. Would this approach work for
> your setup?

My main angle is confidential Kata containers [1], a usage scenario in which (Kubernetes) workload containers run in trusted, confidential VMs on untrusted hosts. This scenario involves hardware TEEs, attestation, and fine-grained policing of host-side inputs. Without getting into too many details, having an untrusted host bake trust anchors into the guest on the fly would undermine the threat model. The proposed IPE keyring gives the trusted guest the ability to construct and sign the IPE policy independently. Also note, outside of the confidential scenario for Kata containers, various Kata containers flavors are very opinionated on the guest boot flow, so I cannot rely on UEFI being present. Having a self-contained mechanism independent of firmware certificate provisioning would therefore be highly preferrable. 

[1] https://confidentialcontainers.org/docs/architecture/