[PATCH v2] boot: Add fit_config_get_hash_list() to build signed node list

[Simon Glass]

Hi Tom,

On Fri, 6 Mar 2026 at 08:12, Tom Rini <trini at konsulko.com> wrote:
>
> On Thu, Mar 05, 2026 at 06:20:09PM -0700, Simon Glass wrote:
>
> > From: Simon Glass <simon.glass at canonical.com>
> >
> > The hashed-nodes property in a FIT signature node lists which FDT paths
> > are included in the signature hash. It is intended as a hint so should
> > not be used for verification.
> >
> > Add a function to build the node list from scratch by iterating the
> > configuration's image references. Skip properties known not to be image
> > references. For each image, collect the path plus all hash and cipher
> > subnodes.
> >
> > Use the new function in fit_config_check_sig() instead of reading
> > 'hashed-nodes'.
> >
> > Update the test_vboot kernel@ test case: fit_check_sign now catches the
> > attack at signature-verification time (the @-suffixed node is hashed
> > instead of the real one, causing a mismatch) rather than at
> > fit_check_format() time.
> >
> > Update the docs to cover this. The FIT spec can be updated separately.
> >
> > Signed-off-by: Simon Glass <simon.glass at canonical.com>
>
> Thanks again for looking in to this!
>
> Closes: https://lore.kernel.org/u-boot/20260302220937.3682128-1-trini@konsulko.com/
> Reported-by: Apple Security Engineering and Architecture (SEAR)
> Tested-by: Tom Rini <trini at konsulko.com>

OK good!

- Simon