TPM resource manager separation

TPM resource manager separation

[Ken Goldman]

Low level question:

Does the RM keep track of which handle / object belongs to which process?

E.g., process A loads a key and gets handle 80ffffff.  Process B then 
tries to do an operation using handle 80ffffff.  Will the RM reject it?

High level question:

Does the RM have any design or capability documentation?  Is there a 
place to get answers other than this mailing list.

Re: TPM resource manager separation

[James Bottomley]

On Fri, 2020-06-05 at 10:45 -0400, Ken Goldman wrote:
> Low level question:
> 
> Does the RM keep track of which handle / object belongs to which
> process?

Sort of: it stores the mappings in a per open file private area.  One
process can have more than one file open to the resource manager,
meaning it could have multiple views of the resource managed TPM, but
by and large there's one open per process meaning you can regard it as
mapping per process.

> E.g., process A loads a key and gets handle 80ffffff.  Process B
> then tries to do an operation using handle 80ffffff.  Will the RM
> reject it?

No, in fact the way the current resource manager works, the first
volatile key loaded by any process using the RM will always appear at
80ffffff.

> High level question:
> 
> Does the RM have any design or capability documentation?  Is there a 
> place to get answers other than this mailing list.

Not really ... perhaps it is time to write a
Documentation/security/tpmrm guide.

James