[PATCH v3 3/3] efi_loader: add DeployedMode and AuditMode variable measurement

[Masahisa Kojima]

On Sat, 2 Oct 2021 at 01:43, Heinrich Schuchardt <xypron.glpk at gmx.de> wrote:
>
>
>
> On 10/1/21 13:18, Masahisa Kojima wrote:
> > This commit adds the DeployedMode and AuditMode variable
> > measurement required in TCG PC Client PFP Spec.
> >
> > Signed-off-by: Masahisa Kojima <masahisa.kojima at linaro.org>
> > ---
> >
> > Changes in v3:
> > - read variable first, then mesure the variable
> >
> >   lib/efi_loader/efi_tcg2.c | 50 +++++++++++++++++++++++++++++++++++++++
> >   1 file changed, 50 insertions(+)
> >
> > diff --git a/lib/efi_loader/efi_tcg2.c b/lib/efi_loader/efi_tcg2.c
> > index 28e0362bf2..7fba4bc458 100644
> > --- a/lib/efi_loader/efi_tcg2.c
> > +++ b/lib/efi_loader/efi_tcg2.c
> > @@ -12,6 +12,7 @@
> >   #include <dm.h>
> >   #include <efi_loader.h>
> >   #include <efi_tcg2.h>
> > +#include <efi_variable.h>
> >   #include <log.h>
> >   #include <malloc.h>
> >   #include <smbios.h>
> > @@ -1822,6 +1823,53 @@ out:
> >       return ret;
> >   }
> >
> > +/**
> > + * tcg2_measure_deployed_audit_mode() - measure deployedmode and auditmode
> > + *
> > + * @dev:     TPM device
> > + *
> > + * Return:   status code
> > + */
> > +static efi_status_t tcg2_measure_deployed_audit_mode(struct udevice *dev)
> > +{
> > +     u8 deployed_mode;
> > +     u8 audit_mode;
> > +     efi_uintn_t size;
> > +     efi_status_t ret;
> > +     u32 pcr_index;
> > +
> > +     size = sizeof(deployed_mode);
> > +     ret = efi_get_variable_int(L"DeployedMode", &efi_global_variable_guid,
> > +                                NULL, &size, &deployed_mode, NULL);
> > +     if (ret != EFI_SUCCESS)
> > +             return ret;
> > +
> > +     size = sizeof(audit_mode);
> > +     ret = efi_get_variable_int(L"AuditMode", &efi_global_variable_guid,
> > +                                NULL, &size, &audit_mode, NULL);
> > +     if (ret != EFI_SUCCESS)
> > +             return ret;
> > +
> > +     pcr_index = (deployed_mode ? 1 : 7);
> > +
> > +     ret = tcg2_measure_variable(dev, pcr_index,
> > +                                 EV_EFI_VARIABLE_DRIVER_CONFIG,
> > +                                 L"DeployedMode",
> > +                                 &efi_global_variable_guid,
> > +                                 size, &deployed_mode);
> > +     if (ret != EFI_SUCCESS)
> > +             return ret;
> > +
> > +
> > +     ret = tcg2_measure_variable(dev, pcr_index,
> > +                                 EV_EFI_VARIABLE_DRIVER_CONFIG,
> > +                                 L"AuditMode",
> > +                                 &efi_global_variable_guid,
> > +                                 size, &audit_mode);
> > +
> > +     return ret;
> > +}
> > +
> >   /**
> >    * tcg2_measure_secure_boot_variable() - measure secure boot variables
> >    *
> > @@ -1885,6 +1933,8 @@ static efi_status_t tcg2_measure_secure_boot_variable(struct udevice *dev)
> >               free(data);
> >       }
> >
> > +     ret = tcg2_measure_deployed_audit_mode(dev);
>
> You do the same thing four times. A loop is preferable.

After your series(efi_loader: centralize known vendor GUIDs) is merged,
I will update this patch to use loop for the secure variables.

Thanks,
Masahisa Kojima

>
> Best regards
>
> Heinrich
>
> > +
> >   error:
> >       return ret;
> >   }
> >