Re: [RFC/RFT v4 0/5] Add generic trusted keys framework/subsystem

From: Mimi Zohar
Date: Thu Aug 15 2019 - 11:06:56 EST


On Thu, 2019-08-15 at 18:33 +0530, Sumit Garg wrote:
> Hi Mimi,
>
> On Wed, 14 Aug 2019 at 18:54, Mimi Zohar <zohar@xxxxxxxxxx> wrote:
> >
> > Hi Sumit,
> >
> > On Tue, 2019-08-13 at 13:22 +0530, Sumit Garg wrote:
> > > This patch-set is an outcome of discussion here [1]. It has evolved very
> > > much since v1 to create, consolidate and generalize trusted keys
> > > subsystem.
> > >
> > > This framework has been tested with trusted keys support provided via TEE
> > > but I wasn't able to test it with a TPM device as I don't possess one. It
> > > would be really helpful if others could test this patch-set using a TPM
> > > device.
> >
> > With the "CONFIG_HEADER_TEST" and "CONFIG_KERNEL_HEADER_TEST" config
> > options enabled, which is required for linux-next, it fails to build.
> >
>
> TBH, I wasn't aware about this test feature for headers.

It's new to me too.

> It looks like
> the header which fails this test is "include/keys/trusted_tpm.h" which
> is basically a rename of "include/keys/trusted.h" plus changes in this
> patch-set.
>
> And "include/keys/trusted.h" header is already put under blacklist
> here: "include/Kbuild +68" as it fails to build. So its that rename
> due to which build failure is observed now.
>
> It seems to be an easy fix for this build failure via following changes:
>
> diff --git a/include/keys/trusted_tpm.h b/include/keys/trusted_tpm.h
> index 7b593447920b..ca1bec0ef65d 100644
> --- a/include/keys/trusted_tpm.h
> +++ b/include/keys/trusted_tpm.h
> @@ -2,6 +2,9 @@
> #ifndef __TRUSTED_TPM_H
> #define __TRUSTED_TPM_H
>
> +#include <keys/trusted-type.h>
> +#include <linux/tpm_command.h>
> +
> /* implementation specific TPM constants */
> #define MAX_BUF_SIZE 1024
> #define TPM_GETRANDOM_SIZE 14
>
> So I will include above changes in this patch-set and also remove
> "include/keys/trusted.h" header from the blacklist.

That works, thanks. ÂWith this patch set, at least the EVM trusted key
is properly being decrypted by the encrypted key with both a TPM 1.2
and PTT TPM 2.0. ÂMy laptop still boots properly. ÂOver the weekend
I'll try to actually review the patches.

Mimi