Attestation with a quantified trusted computing base

1. An apparatus comprising:

a processor; and

a memory coupled to the processor, the memory having instructions stored thereon that, in response to execution by the processor, cause the processor to:

generate a trusted computing base (TCB) component identifier (TCI) of a current component of the computing system;

generate a compound device identifier (ID) (CDI) of the current component from a CDI of a previous component of the computing system and the TCI of the current component;

determine a size of the TCI of the current component;

sum the size of the TCI of the current component and sizes of the TCIs of previous components of the computing system to generate a current cumulative size;

combine the current cumulative size and the CDI of the current component; and

include the combined current cumulative size and the CDI of the current component in a chain of measurements for attestation of the computing system.

2. The apparatus of claim 1 , wherein a trusted computing base (TCB) of the computing system includes the current component and the previous components.

3. The apparatus of claim 1 , wherein the TCI of the current component is in binary form and the size is measured in bytes.

4. The apparatus of claim 1 , further comprising instructions, when executed, to send the chain of measurements to a verifier to attest to trust of the computing system.

5. The apparatus of claim 1 , further comprising instructions, when executed, to:

hash a concatenation of a cumulative TCI of the previous component and the TCI of the current component to generate a current cumulative TCI of the current component;

combine the current cumulative TCI of the current component and CDI of the current component; and

include the combined current cumulative TCI of the current component and the CDI of the current component in the chain of measurements for attestation of the computing system.

6. The apparatus of claim 5 , further comprising instructions, when executed, to:

combine the current cumulative TCI of the current component, the current cumulative size, and the CDI of the current component; and

include the current cumulative TCI of the current component, the current cumulative size, and the CDI of the current component in the chain of measurements for attestation of the computing system.

7. The apparatus of claim 5 , wherein the current cumulative TCI is a measurement of complexity of the current component and all previous components.

8. The apparatus of claim 1 , wherein the current cumulative size is a measurement of complexity of the current component and all previous components.

9. A method comprising:

generating a trusted computing base (TCB) component identifier (TCI) of a current component of a computing system;

generating a compound device identifier (ID) (CDI) of the current component from a CDI of a previous component of the computing system and the TCI of the current component;

determining a size of the TCI of the current component;

summing the size of the TCI of the current component and sizes of the TCIs of previous components of the computing system to generate a current cumulative size;

combining the current cumulative size and the CDI of the current component; and

including the combined current cumulative size and the CDI of the current component in a chain of measurements for attestation of the computing system.

10. The method of claim 9 , wherein a trusted computing base (TCB) of the computing system includes the current component and the previous components.

11. The method of claim 9 , wherein the TCI of the current component is in binary form and the size is measured in bytes.

12. The method of claim 9 , comprising sending the chain of measurements to a verifier to attest to trust of the computing system.

13. The method of claim 9 , comprising:

hashing a concatenation of a cumulative TCI of the previous component and the TCI of the current component to generate a current cumulative TCI of the current component;

combining the current cumulative TCI of the current component and CDI of the current component; and

including the combined current cumulative TCI of the current component and the CDI of the current component in the chain of measurements for attestation of the computing system.

14. The method of claim 13 , comprising:

combining the current cumulative TCI of the current component, the current cumulative size, and the CDI of the current component; and

including the current cumulative TCI of the current component, the current cumulative size, and the CDI of the current component in the chain of measurements for attestation of the computing system.

15. The method of claim 13 , wherein the current cumulative TCI is a measurement of complexity of the current component and all previous components.

16. The method of claim 9 , wherein the current cumulative size is a measurement of complexity of the current component and all previous components.

17. At least one non-transitory machine-readable storage medium comprising instructions that, when executed, cause at least one processing device to at least:

generate a trusted computing base (TCB) component identifier (TCI) of a current component of a computing system;

generate a compound device identifier (ID) (CDI) of the current component from a CDI of a previous component of the computing system and the TCI of the current component;

determine a size of the TCI of the current component;

sum the size of the TCI of the current component and sizes of the TCIs of previous components of the computing system to generate a current cumulative size;

combine the current cumulative size and the CDI of the current component; and

include the combined current cumulative size and the CDI of the current component in a chain of measurements for attestation of the computing system.

18. The at least one non-transitory machine-readable storage medium of claim 17 , comprising instructions that, when executed, cause at least one processing device to send the chain of measurements to a verifier to attest to trust of the computing system.

19. The at least one non-transitory machine-readable storage medium of claim 17 , comprising instructions that, when executed, cause at least one processing device to:

hash a concatenation of a cumulative TCI of the previous component and the TCI of the current component to generate a current cumulative TCI of the current component;

combine the current cumulative TCI of the current component and CDI of the current component; and

include the combined current cumulative TCI of the current component and the CDI of the current component in the chain of measurements for attestation of the computing system.

20. The at least one non-transitory machine-readable storage medium of claim 17 , comprising instructions that, when executed, cause at least one processing device to:

combine the current cumulative TCI of the current component, the current cumulative size, and the CDI of the current component; and

include the current cumulative TCI of the current component, the current cumulative size, and the CDI of the current component in the chain of measurements for attestation of the computing system.