Project Cerberus
As part of the Open Compute Project (OCP), Project Cerberus defines a hierarchical Root of Trust (RoT) architecture. All active components are required to support both hardware and firmware combined identifing through the Device Identifier Composition Engine (DICE).
Figure 4-3 thru 4-6 describe the power on sequence, boot flow, recovery flow, and firmware update flow.
Figure 4-3: Cerberus power on sequence (source: “Project Cerberus Hardware Security”)
Figure 4-4: Cerberus boot flow (source: “Project Cerberus Hardware Security”)
Figure 4-5: Cerberus recovery flow (source: “Project Cerberus Hardware Security”)
Figure 4-6: Cerberus firmware update (source: “Project Cerberus Hardware Security”)
The concept of Cerberus is similar to Intel® Boot Guard., but there are several key differences:
- Intel® Boot Guard uses Microcode as RoT, while Cerberus uses a dedicated RoT device.
- Intel® Boot Guard can mitigate hardware bus attacks.
- Intel® Boot Guard only verifies the host system firmware, while Cerberus verifies all boot firmware (platform firmware, BMC, etc.)
- Cerberus defines a detailed flow for update and recovery.
Table 4-3: Cerberus Boot
Item | Entity | Provider | Location |
---|---|---|---|
TP | Boot Firmware Verification (in Cerberus Microcontroller) | OEM | Flash (Read Only Code), Device ROM. |
CDI | Cerberus Microcontroller | OEM | Flash (Read Only Code), Device ROM. |
Boot Firmware Signature Database (Policy) | OEM | Flash (Read Only Data), ROM | |
UDI | Boot Firmware (BMC, Firmware) | OEM/IHV | Flash (Read Only Data) – active area |
Table 4-4: Cerberus Recovery
Item | Entity | Provider | Location |
---|---|---|---|
TP | Boot Firmware Verification (in Cerberus Microcontroller) | OEM | Flash (Read Only Code), Device ROM. |
CDI | Cerberus Microcontroller | OEM | Flash (Read Only Code), Device ROM. |
Boot Firmware Signature Database (Policy) | OEM | Flash (Read Only Data), ROM | |
UDI | Boot Firmware Recovery (BMC, Firmware) | OEM/IHV | Flash (Read Only Data) - recovery area |
Table 4-5: Cerberus Firmware Update
Item | Entity | Provider | Location |
---|---|---|---|
TP | Boot Firmware Verification (in Cerberus Microcontroller) | OEM | Flash (Read Only Code), Device ROM. |
CDI | Cerberus Microcontroller | OEM | Flash (Read Only Code), Device ROM. |
Boot Firmware Signature Database (Policy) | OEM | Flash (Read Only Data), ROM | |
UDI | Boot Firmware (BMC, Firmware) | OEM/IHV | Flash (Read Only Data) – staging area |