[PATCH v3 5/5] doc:eficonfig: add description for UEFI Secure Boot Configuration

[Masahisa Kojima]

Hi Ilias,

On Fri, 2 Dec 2022 at 16:17, Ilias Apalodimas
<ilias.apalodimas at linaro.org> wrote:
>
> On Fri, Dec 02, 2022 at 01:59:37PM +0900, Masahisa Kojima wrote:
> > This commits add the description for the UEFI Secure Boot
> > Configuration through the eficonfig menu.
> >
> > Signed-off-by: Masahisa Kojima <masahisa.kojima at linaro.org>
> > ---
> > No update since v2
> >
> > Newly created in v2
> >
> >  doc/usage/cmd/eficonfig.rst | 22 ++++++++++++++++++++++
> >  1 file changed, 22 insertions(+)
> >
> > diff --git a/doc/usage/cmd/eficonfig.rst b/doc/usage/cmd/eficonfig.rst
> > index 340ebc80db..67c859964f 100644
> > --- a/doc/usage/cmd/eficonfig.rst
> > +++ b/doc/usage/cmd/eficonfig.rst
> > @@ -31,6 +31,9 @@ Change Boot Order
> >  Delete Boot Option
> >      Delete the UEFI Boot Option
> >
> > +Secure Boot Configuration
> > +    Edit UEFI Secure Boot Configuration
> > +
> >  Configuration
> >  -------------
> >
> > @@ -44,6 +47,16 @@ U-Boot console. In this case, bootmenu can be used to invoke "eficonfig"::
> >      CONFIG_USE_PREBOOT=y
> >      CONFIG_PREBOOT="setenv bootmenu_0 UEFI Maintenance Menu=eficonfig"
> >
> > +UEFI specification requires that UEFI Secure Boot Configuration (especially
> > +for PK and KEK) is stored in non-volatile storage which is tamper resident.
>
> s/resident/resistant

Thank you for pointing out the typo.

>
> > +CONFIG_EFI_MM_COMM_TEE is mandatory to provide the secure storage in U-Boot.
>
> Can we be a bit more clear here. Something along the lines of
> "The only way U-Boot can currently store EFI variables on a tamper
> resistant medium is via OP-TEE.  The Kconfig option that enables that is
> CONFIG_EFI_MM_COMM_TEE and ends up storing EFI variables on an RPMB
> partition of an eMMC"

OK, it is clearer.

>
> > +UEFI Secure Boot Configuration menu entry is enabled when the following
> > +options are enabled::
> > +
> > +    CONFIG_EFI_SECURE_BOOT=y
> > +    CONFIG_EFI_MM_COMM_TEE=y
> > +
> > +
> >  How to boot the system with newly added UEFI Boot Option
> >  ''''''''''''''''''''''''''''''''''''''''''''''''''''''''
> >
> > @@ -66,6 +79,15 @@ add "bootefi bootmgr" entry as a default or first bootmenu entry::
> >
> >      CONFIG_PREBOOT="setenv bootmenu_0 UEFI Boot Manager=bootefi bootmgr; setenv bootmenu_1 UEFI Maintenance Menu=eficonfig"
> >
> > +UEFI Secure Boot Configuration
> > +''''''''''''''''''''''''''''''
> > +
> > +User can enroll PK, KEK, db and dbx by selecting file.
>
> selecting a file

OK.

Thanks,
Masahisa Kojima

>
> > +"eficonfig" command only accepts the signed EFI Signature List(s)
> > +with an authenticated header, typically ".auth" file.
> > +To clear the PK, KEK, db and dbx, user needs to enroll the null key
> > +signed by PK or KEK.
> > +
> >  See also
> >  --------
> >  * :doc:`bootmenu<bootmenu>` provides a simple mechanism for creating menus with different boot items
> > --
> > 2.17.1
> >
>
> Thanks
> /Ilias