Re: [PATCH v10 7/8] security: keys: trusted: add ability to specify arbitrary policy

[Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>]

On Thu, Jun 18, 2020 at 12:45:14PM -0700, James Bottomley wrote:
> On Thu, 2020-06-18 at 10:12 +0300, Jarkko Sakkinen wrote:
> > On Wed, Jun 17, 2020 at 05:27:43PM -0700, James Bottomley wrote:
> > > On Thu, 2020-06-18 at 02:42 +0300, Jarkko Sakkinen wrote:
> > > > On Tue, Jun 16, 2020 at 09:02:28AM -0700, James Bottomley wrote:
> > > > > This patch adds a policy= argument to key creation.  The policy
> > > > > is
> > > > > the standard tss policymaker format and each separate policy
> > > > > line
> > > > > must have a newline after it.
> > > > 
> > > > Never heard of policymaker before and did not find TCG spec for
> > > > it.
> > > 
> > > It's not part of the spec.  Both the IBM and Intel TSSs define a
> > > policymaker tool to help you build policy hashes.  The format is
> > > simply
> > > a set of numbers that if hashed a line at a time produce the policy
> > > hash.
> > 
> > OK, so they both use this 'policymaker' format? Where is it
> > documented?
> 
> I don't think it is except in the source code of the tools.  It's
> basically a sequence of TPM2_PolicyXX statements laid out in binary end
> to end one per line as the TPM2 command value says they are hashed.  I
> can just say that if you prefer.  The example given is

There is no "the tools". There are multiple user space stacks.

I think that the format should be documented to Documents/security/tpm.

/Jarkko