Auditing the TPM

Auditing the TPM

[Matt Anderson]

I have been experimenting with the TPM and the TrouSerS package some and
have so far come up with this list of possible events that could be
interesting from a OS auditing perspective:

    * Taking Ownership of the TPM
    * Clearing Ownership
    * Dis/Enabling the TPM
    * Dis/Activating the TPM
    * Recording PCR values
    * Adjustments to PCR values
    * Remote attestation connections/commands and their results
    * Requests of the Public Endorsement Key (EK)
    * Adjustments to the access controls on the EK
    * Creating/Destroying the EK
    * Changes to the TPM locked status (set/reset)


For some of these events it makes sense that the auditing would happen
in the TPM kernel driver, other events will need to be audited up in
user space to accurately capture all the important information.  Has
anyone in this community begun looking at what TPM events are
interesting from an audit perspective?

thanks
-matt

Re: Auditing the TPM

[Steve Grubb]

On Thursday 03 January 2008 14:22:45 Matt Anderson wrote:
> Has anyone in this community begun looking at what TPM events are
> interesting from an audit perspective?

Not that I know of. No one has contacted me for event types. Are there any 
standards that define what is supposed to be audited?

-Steve

Re: Auditing the TPM

[Matt Anderson]

Steve Grubb wrote:
> On Thursday 03 January 2008 14:22:45 Matt Anderson wrote:
>> Has anyone in this community begun looking at what TPM events are
>> interesting from an audit perspective?
> 
> Not that I know of. No one has contacted me for event types. Are there any 
> standards that define what is supposed to be audited?

The Trusted Computing Group spec 1.2 allow for auditing events that the
TPM processes, but it only says that the owner should be able to set
which events get audited and which shouldn't, suggesting "There will be
a very limited number of audited commands, most likely those commands
that provide identities and control of the TPM. Commands such as unseal
would not be audited, they would use the logging functions of a
transport session."

Other than that spec I am unaware of other standards that might be
applicable.  I will investigate that further, but if anyone can think of
any please let me know.

-matt