Re: [PATCH] IMA: Handle early boot data measurement

[Lakshmi Ramasubramanian]

On 8/25/20 8:40 AM, Mimi Zohar wrote:
> On Fri, 2020-08-21 at 16:12 -0700, Lakshmi Ramasubramanian wrote:
> > The current implementation of early boot measurement in
> > the IMA subsystem is very specific to asymmetric keys. It does not
> > handle early boot measurement of data from other subsystems such as
> > Linux Security Module (LSM), Device-Mapper, etc. As a result data,
> > provided by these subsystems during system boot are not measured by IMA.
> >
> > Update the early boot key measurement to handle any early boot data.
> > Refactor the code from ima_queue_keys.c to a new file ima_queue_data.c.
> > Rename the kernel configuration CONFIG_IMA_QUEUE_EARLY_BOOT_KEYS to
> > CONFIG_IMA_QUEUE_EARLY_BOOT_DATA so it can be used for enabling any
> > early boot data measurement. Since measurement of asymmetric keys is
> > the first consumer of early boot measurement, this kernel configuration
> > is enabled if IMA_MEASURE_ASYMMETRIC_KEYS and SYSTEM_TRUSTED_KEYRING are
> > both enabled.
> >
> > Update the IMA hook ima_measure_critical_data() to utilize early boot
> > measurement support.
>
> Please limit the changes in this patch to renaming the functions and/or
> files.  For example, adding "measure_payload_hash" should be a separate
> patch, not hidden here.

Thanks for the feedback Mimi.

I'll split this into 2 patches:

PATCH 1: Rename files + rename CONFIG
PATCH 2: Update IMA hook to utilize early boot data measurement.

 -lakshmi