Re: [PATCH v1] IMA: fix measuring asymmetric keys Kconfig

From: Mimi Zohar
Date: Wed Jan 08 2020 - 23:52:36 EST


On Wed, 2020-01-08 at 08:05 -0800, Lakshmi Ramasubramanian wrote:
> CONFIG_ASYMMETRIC_PUBLIC_KEY_SUBTYPE is a tristate. If this config
> is set to "=m", ima_asymmetric_keys.c is built as a kernel module.
>
> Defined an intermediate boolean config namely
> CONFIG_IMA_MEASURE_ASYMMETRIC_KEYS that is
> defined when CONFIG_IMA and CONFIG_ASYMMETRIC_PUBLIC_KEY_SUBTYPE
> are defined.
>
> Asymmetric key structure is defined only when
> CONFIG_ASYMMETRIC_PUBLIC_KEY_SUBTYPE is defined. Since the IMA hook
> measures asymmetric keys, the IMA hook is defined in
> ima_asymmetric_keys.c which is built only if
> CONFIG_IMA_MEASURE_ASYMMETRIC_KEYS is defined.
>
> Signed-off-by: Lakshmi Ramasubramanian <nramas@xxxxxxxxxxxxxxxxxxx>

For the time being, I've pushed out this patch with the existing patch
description to next-integrity-testing, but the patch description
should be rewritten clearer. ÂFor example,

As a result of the asymmetric public keys subtype being defined as a
tristate, with the existing IMA Makefile, ima_asymmetric_keys.c could
be built as a kernel module. ÂTo prevent this from happening, this
patch defines and uses an intermediate Kconfig boolean option named
IMA_MEASURE_ASYMMETRIC_KEYS.

Please let me know if you're ok with this wording.

thanks,

Mimi