Security has multiple layers and dimensions. Such as:
- How the operator manages keys for signing. This includes TUF key management for signing what can be installed. It also includes how boot firmware is signed so that the hardware boot ROM will trust it.
- Device security - how devices store secure artifacts.
- Connection security - how devices and cloud services trust each other.
TUF is the mechanism by which the Foundries.io backend informs devices what software they can run. The TUF targets.json includes a software description that’s pinned to secure hashes of all components so that a device can know that it is running the correct payload. TUF keys need to be managed by a customer offline in order to generate production targets.
Secure Boot (Hardware Root of Trust)¶
Secure Boot is the mechanism used to force a device to only execute boot software that is signed by a certain set of keys. The verification process and respective security functions are performed by the SoC boot ROM, and these are the starting points for building a hardware root of trust.
The SoC hardware security manual should be consulted for identifying the supported key types and the signing process required for establishing the hardware root of trust.
Devices employ multiple mechanisms to achieve security. First, they can take advantage of a Hardware Security Element(HSM) to ensure secrets are store securely.
These secrets are then generated/used by a secure provisioning process that allows devices a safe way to self-register with our cloud service.