I am developing a daemon-based product that needs a cryptographic, non-spoofable proof of machine identity so a remote management server can grant permissions based on the physical machine.
I was thinking to create a signing key in the Secure Enclave and use a certificate signed by that key as the machine identity. The problem is that the Secure Enclave key I can create is only accessible from user context, while my product runs as a system daemon and must not rely on user processes or launchAgents.
Could you please advise on the recommended Apple-supported approaches for this use case ?
Specifically, Is there a supported way for a system daemon to generate and use an unremovable Secure Enclave key during phases like the pre-logon, that doesn't have non user context (only the my application which created this key/certificate will have permission to use/delete it)
If Secure Enclave access from a daemon is not supported, what Apple-recommended alternatives exist for providing a hardware-backed machine identity for system daemons? I'd rather avoid using system keychain, as its contents may be removed or used by root privileged users.
The ideal solution would be that each Apple product, would come out with a non removable signing certificate, that represent the machine itself (lets say that the cetificate name use to represent the machine ID), and can be validated by verify that the root signer is "Apple Root CA"