Re: [PATCH v18 18/25] util/grub-protect: Add new tool

[Gary Lin]

On Fri, Aug 30, 2024 at 05:49:04PM +0200, Daniel Kiper wrote:
> On Fri, Jun 28, 2024 at 04:19:01PM +0800, Gary Lin via Grub-devel wrote:
> > From: Hernan Gatta <hegatta@linux.microsoft.com>
> >
> > To utilize the key protectors framework, there must be a way to protect
> > full-disk encryption keys in the first place. The grub-protect tool
> > includes support for the TPM2 key protector but other protectors that
> > require setup ahead of time can be supported in the future.
> >
> > For the TPM2 key protector, the intended flow is for a user to have a
> > LUKS 1 or LUKS 2-protected fully-encrypted disk. The user then creates a
> > new LUKS key file, say by reading /dev/urandom into a file, and creates
> > a new LUKS key slot for this key. Then, the user invokes the grub-protect
> > tool to seal this key file to a set of PCRs using the system's TPM 2.0.
> > The resulting sealed key file is stored in an unencrypted partition such
> > as the EFI System Partition (ESP) so that GRUB may read it. The user also
> > has to ensure the cryptomount command is included in GRUB's boot script
> > and that it carries the requisite key protector (-P) parameter.
> >
> > Sample usage:
> >
> > $ dd if=/dev/urandom of=luks-key bs=1 count=32
> > $ sudo cryptsetup luksAddKey /dev/sdb1 luks-key --pbkdf=pbkdf2 --hash=sha512
> >
> > To seal the key with TPM 2.0 Key File (recommended):
> >
> > $ sudo grub-protect --action=add \
> >                     --protector=tpm2 \
> >                 --tpm2-pcrs=0,2,4,7,9 \
> >                     --tpm2key \
> >                     --tpm2-keyfile=luks-key \
> >                     --tpm2-outfile=/boot/efi/boot/grub2/sealed.tpm
> >
> > Or, to seal the key with the raw sealed key:
> >
> > $ sudo grub-protect --action=add \
> >                     --protector=tpm2 \
> >                 --tpm2-pcrs=0,2,4,7,9 \
> >                     --tpm2-keyfile=luks-key \
> >                     --tpm2-outfile=/boot/efi/boot/grub2/sealed.key
> >
> > Then, in the boot script, for TPM 2.0 Key File:
> >
> > tpm2_key_protector_init --tpm2key=(hd0,gpt1)/boot/grub2/sealed.tpm
> > cryptomount -u <SDB1_UUID> -P tpm2
> >
> > Or, for the raw sealed key:
> >
> > tpm2_key_protector_init --keyfile=(hd0,gpt1)/boot/grub2/sealed.key 
> > --pcrs=0,2,4,7,9
> > cryptomount -u <SDB1_UUID> -P tpm2
> >
> > The benefit of using TPM 2.0 Key File is that the PCR set is already
> > written in the key file, so there is no need to specify PCRs when
> > invoking tpm2_key_protector_init.
> 
> I think most if not all of this commit message should go to the GRUB
> documentation too.
> 
I'm working on an additional commit to address TPM2 key protector,
grub-protect, and grub-emu in docs/grub.texi.

> > Cc: Stefan Berger <stefanb@linux.ibm.com>
> > Signed-off-by: Hernan Gatta <hegatta@linux.microsoft.com>
> > Signed-off-by: Gary Lin <glin@suse.com>
> > ---
> >  .gitignore                |    2 +
> >  Makefile.util.def         |   26 +
> >  configure.ac              |   30 +
> >  docs/man/grub-protect.h2m |    4 +
> >  util/grub-protect.c       | 1423 +++++++++++++++++++++++++++++++++++++
> >  5 files changed, 1485 insertions(+)
> >  create mode 100644 docs/man/grub-protect.h2m
> >  create mode 100644 util/grub-protect.c
> >
> > diff --git a/.gitignore b/.gitignore
> > index 4c1f91db8..2105d87c8 100644
> > --- a/.gitignore
> > +++ b/.gitignore
> > @@ -169,6 +169,8 @@ widthspec.bin
> >  /grub-ofpathname.exe
> >  /grub-probe
> >  /grub-probe.exe
> > +/grub-protect
> > +/grub-protect.exe
> >  /grub-reboot
> >  /grub-render-label
> >  /grub-render-label.exe
> > diff --git a/Makefile.util.def b/Makefile.util.def
> > index fb82f59a0..074c0aff7 100644
> > --- a/Makefile.util.def
> > +++ b/Makefile.util.def
> > @@ -208,6 +208,32 @@ program = {
> >    ldadd = '$(LIBINTL) $(LIBDEVMAPPER) $(LIBZFS) $(LIBNVPAIR) $(LIBGEOM)';
> >  };
> >
> > +program = {
> > +  name = grub-protect;
> > +  mansection = 1;
> > +
> > +  common = grub-core/kern/emu/argp_common.c;
> > +  common = grub-core/osdep/init.c;
> > +  common = grub-core/lib/tss2/buffer.c;
> > +  common = grub-core/lib/tss2/tss2_mu.c;
> > +  common = grub-core/lib/tss2/tpm2_cmd.c;
> > +  common = grub-core/commands/tpm2_key_protector/args.c;
> > +  common = grub-core/commands/tpm2_key_protector/tpm2key_asn1_tab.c;
> > +  common = util/grub-protect.c;
> > +  common = util/probe.c;
> > +
> > +  cflags = '-I$(srcdir)/grub-core/lib/tss2 
> > -I$(srcdir)/grub-core/commands/tpm2_key_protector';
> > +
> > +  ldadd = libgrubmods.a;
> > +  ldadd = libgrubgcry.a;
> > +  ldadd = libgrubkern.a;
> > +  ldadd = grub-core/lib/gnulib/libgnu.a;
> > +  ldadd = '$(LIBTASN1)';
> > +  ldadd = '$(LIBINTL) $(LIBDEVMAPPER) $(LIBUTIL) $(LIBZFS) $(LIBNVPAIR) 
> > $(LIBGEOM)';
> > +
> > +  condition = COND_GRUB_PROTECT;
> > +};
> > +
> >  program = {
> >    name = grub-mkrelpath;
> >    mansection = 1;
> > diff --git a/configure.ac b/configure.ac
> > index d4a14bf93..12681c19c 100644
> > --- a/configure.ac
> > +++ b/configure.ac
> > @@ -76,6 +76,7 @@ grub_TRANSFORM([grub-mkpasswd-pbkdf2])
> >  grub_TRANSFORM([grub-mkrelpath])
> >  grub_TRANSFORM([grub-mkrescue])
> >  grub_TRANSFORM([grub-probe])
> > +grub_TRANSFORM([grub-protect])
> >  grub_TRANSFORM([grub-reboot])
> >  grub_TRANSFORM([grub-script-check])
> >  grub_TRANSFORM([grub-set-default])
> > @@ -2057,6 +2058,29 @@ fi
> >  AC_SUBST([LIBZFS])
> >  AC_SUBST([LIBNVPAIR])
> >
> > +AC_ARG_ENABLE([grub-protect],
> > +         [AS_HELP_STRING([--enable-grub-protect],
> > +                             [build and install the `grub-protect' utility 
> > (default=guessed)])])
> > +if test x"$enable_grub_protect" = xno ; then
> > +  grub_protect_excuse="explicitly disabled"
> > +fi
> > +
> > +LIBTASN1=
> > +if test x"$grub_protect_excuse" = x ; then
> > +  AC_CHECK_LIB([tasn1], [asn1_write_value], [LIBTASN1="-ltasn1"], 
> > [grub_protect_excuse="need libtasn1 library"])
> > +fi
> > +AC_SUBST([LIBTASN1])
> > +
> > +if test x"$enable_grub_protect" = xyes && test x"$grub_protect_excuse" != 
> > x ; then
> > +  AC_MSG_ERROR([grub-protect was explicitly requested but can't be 
> > compiled ($grub_protect_excuse)])
> > +fi
> > +if test x"$grub_protect_excuse" = x ; then
> > +enable_grub_protect=yes
> > +else
> > +enable_grub_protect=no
> > +fi
> > +AC_SUBST([enable_grub_protect])
> > +
> >  LIBS=""
> >
> >  AC_SUBST([FONT_SOURCE])
> > @@ -2173,6 +2197,7 @@ AM_CONDITIONAL([COND_GRUB_EMU_SDL], [test 
> > x$enable_grub_emu_sdl = xyes])
> >  AM_CONDITIONAL([COND_GRUB_EMU_PCI], [test x$enable_grub_emu_pci = xyes])
> >  AM_CONDITIONAL([COND_GRUB_MKFONT], [test x$enable_grub_mkfont = xyes])
> >  AM_CONDITIONAL([COND_GRUB_MOUNT], [test x$enable_grub_mount = xyes])
> > +AM_CONDITIONAL([COND_GRUB_PROTECT], [test x$enable_grub_protect = xyes])
> >  AM_CONDITIONAL([COND_HAVE_FONT_SOURCE], [test x$FONT_SOURCE != x])
> >  if test x$FONT_SOURCE != x ; then
> >     HAVE_FONT_SOURCE=1
> > @@ -2300,6 +2325,11 @@ echo grub-mount: Yes
> >  else
> >  echo grub-mount: No "($grub_mount_excuse)"
> >  fi
> > +if [ x"$grub_protect_excuse" = x ]; then
> > +echo grub-protect: Yes
> > +else
> > +echo grub-protect: No "($grub_protect_excuse)"
> > +fi
> >  if [ x"$starfield_excuse" = x ]; then
> >  echo starfield theme: Yes
> >  echo With DejaVuSans font from $DJVU_FONT_SOURCE
> > diff --git a/docs/man/grub-protect.h2m b/docs/man/grub-protect.h2m
> > new file mode 100644
> > index 000000000..3bfa8b645
> > --- /dev/null
> > +++ b/docs/man/grub-protect.h2m
> > @@ -0,0 +1,4 @@
> > +[NAME]
> > +grub-protect \- protect a disk key with a key protector
> > +[DESCRIPTION]
> > +grub-protect helps to pretect a disk encryption key with a specified key 
> > protector.
> 
> Please expand this too...
> 
Ok, I'll expand the decription and add some samples.

> > diff --git a/util/grub-protect.c b/util/grub-protect.c
> > new file mode 100644
> > index 000000000..62b764b41
> > --- /dev/null
> > +++ b/util/grub-protect.c
> > @@ -0,0 +1,1423 @@
> > +/*
> > + *  GRUB  --  GRand Unified Bootloader
> > + *  Copyright (C) 2024 Free Software Foundation, Inc.
> > + *  Copyright (C) 2023 SUSE LLC
> > + *  Copyright (C) 2022 Microsoft Corporation
> > + *
> > + *  GRUB is free software: you can redistribute it and/or modify
> > + *  it under the terms of the GNU General Public License as published by
> > + *  the Free Software Foundation, either version 3 of the License, or
> > + *  (at your option) any later version.
> > + *
> > + *  GRUB is distributed in the hope that it will be useful,
> > + *  but WITHOUT ANY WARRANTY; without even the implied warranty of
> > + *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> > + *  GNU General Public License for more details.
> > + *
> > + *  You should have received a copy of the GNU General Public License
> > + *  along with GRUB.  If not, see <http://www.gnu.org/licenses/>.
> > + */
> > +
> > +#include <config.h>
> > +
> > +#include <errno.h>
> > +#include <fcntl.h>
> > +#include <libtasn1.h>
> > +#include <stdio.h>
> > +#include <string.h>
> > +#include <unistd.h>
> > +
> > +#include <grub/emu/hostdisk.h>
> > +#include <grub/emu/misc.h>
> > +
> > +#include <grub/util/misc.h>
> > +
> > +#include <tss2_buffer.h>
> > +#include <tss2_mu.h>
> > +#include <tcg2.h>
> > +#include <tpm2_args.h>
> > +#include <tpm2.h>
> > +
> > +#pragma GCC diagnostic ignored "-Wmissing-prototypes"
> > +#pragma GCC diagnostic ignored "-Wmissing-declarations"
> > +#include <argp.h>
> > +#pragma GCC diagnostic error "-Wmissing-prototypes"
> > +#pragma GCC diagnostic error "-Wmissing-declarations"
> 
> I can see this in other utils sources but it would be nice to know
> it is still needed, and why, or not...
> 
> > +#include "progname.h"
> > +
> > +/* Unprintable option keys for argp */
> > +typedef enum grub_protect_opt
> > +{
> > +  /* General */
> > +  GRUB_PROTECT_OPT_ACTION      = 'a',
> > +  GRUB_PROTECT_OPT_PROTECTOR   = 'p',
> > +  /* TPM2 */
> > +  GRUB_PROTECT_OPT_TPM2_DEVICE = 0x100,
> > +  GRUB_PROTECT_OPT_TPM2_PCRS,
> > +  GRUB_PROTECT_OPT_TPM2_ASYMMETRIC,
> > +  GRUB_PROTECT_OPT_TPM2_BANK,
> > +  GRUB_PROTECT_OPT_TPM2_SRK,
> > +  GRUB_PROTECT_OPT_TPM2_KEYFILE,
> > +  GRUB_PROTECT_OPT_TPM2_OUTFILE,
> > +  GRUB_PROTECT_OPT_TPM2_EVICT,
> > +  GRUB_PROTECT_OPT_TPM2_TPM2KEY
> > +} grub_protect_opt;
> > +
> > +/* Option flags to keep track of specified arguments */
> > +typedef enum grub_protect_arg
> > +{
> > +  /* General */
> > +  GRUB_PROTECT_ARG_ACTION          = 1 << 0,
> > +  GRUB_PROTECT_ARG_PROTECTOR       = 1 << 1,
> > +  /* TPM2 */
> > +  GRUB_PROTECT_ARG_TPM2_DEVICE     = 1 << 2,
> > +  GRUB_PROTECT_ARG_TPM2_PCRS       = 1 << 3,
> > +  GRUB_PROTECT_ARG_TPM2_ASYMMETRIC = 1 << 4,
> > +  GRUB_PROTECT_ARG_TPM2_BANK       = 1 << 5,
> > +  GRUB_PROTECT_ARG_TPM2_SRK        = 1 << 6,
> > +  GRUB_PROTECT_ARG_TPM2_KEYFILE    = 1 << 7,
> > +  GRUB_PROTECT_ARG_TPM2_OUTFILE    = 1 << 8,
> > +  GRUB_PROTECT_ARG_TPM2_EVICT      = 1 << 9,
> > +  GRUB_PROTECT_ARG_TPM2_TPM2KEY    = 1 << 10
> > +} grub_protect_arg_t;
> > +
> > +typedef enum grub_protect_protector
> > +{
> > +  GRUB_PROTECT_TYPE_ERROR,
> > +  GRUB_PROTECT_TYPE_TPM2
> > +} grub_protect_protector_t;
> > +
> > +typedef enum grub_protect_action
> > +{
> > +  GRUB_PROTECT_ACTION_ERROR,
> > +  GRUB_PROTECT_ACTION_ADD,
> > +  GRUB_PROTECT_ACTION_REMOVE
> > +} grub_protect_action_t;
> > +
> > +struct grub_protect_args
> > +{
> > +  grub_protect_arg_t args;
> > +  grub_protect_action_t action;
> > +  grub_protect_protector_t protector;
> > +
> > +  const char *tpm2_device;
> > +  grub_uint8_t tpm2_pcrs[TPM_MAX_PCRS];
> > +  grub_uint8_t tpm2_pcr_count;
> > +  grub_srk_type_t srk_type;
> > +  TPM_ALG_ID tpm2_bank;
> > +  TPM_HANDLE tpm2_srk;
> > +  const char *tpm2_keyfile;
> > +  const char *tpm2_outfile;
> > +  int tpm2_evict;
> > +  int tpm2_tpm2key;
> > +};
> > +
> > +static struct argp_option grub_protect_options[] =
> > +  {
> > +    /* Top-level options */
> > +   {
> > +      .name  = "action",
> > +      .key   = 'a',
> > +      .arg   = "add|remove",
> > +      .flags = 0,
> > +      .doc   =
> > +   N_("Add or remove a key protector to or from a key."),
> > +      .group = 0
> > +    },
> > +    {
> > +      .name  = "protector",
> > +      .key   = 'p',
> > +      .arg   = "tpm2",
> > +      .flags = 0,
> > +      .doc   =
> > +   N_("Key protector to use (only tpm2 is currently supported)."),
> > +      .group = 0
> > +    },
> > +    /* TPM2 key protector options */
> > +    {
> > +      .name = "tpm2-device",
> > +      .key   = GRUB_PROTECT_OPT_TPM2_DEVICE,
> > +      .arg   = "FILE",
> > +      .flags = 0,
> > +      .doc   =
> > +   N_("Path to the TPM2 device. (default: /dev/tpm0)"),
> > +      .group = 0
> > +    },
> > +    {
> > +      .name = "tpm2-pcrs",
> > +      .key   = GRUB_PROTECT_OPT_TPM2_PCRS,
> > +      .arg   = "0[,1]...",
> > +      .flags = 0,
> > +      .doc   =
> > +   N_("Comma-separated list of PCRs used to authorize key release "
> > +      "e.g., '7,11'. Please be aware that PCR 0~7 are used by the "
> > +      "firmware and the measurement result may change after a "
> > +      "firmware update (for baremetal systems) or a package "
> > +      "(OVMF/SeaBIOS/SLOF) update in the VM host. This may lead to"
> > +      "the failure of key unsealing. (default: 7)"),
> 
> I would add this to the GRUB docs too.
> 
Sure. I'll address the PCR usage in grub.texi.

> > +      .group = 0
> > +    },
> > +    {
> > +      .name = "tpm2-bank",
> > +      .key  = GRUB_PROTECT_OPT_TPM2_BANK,
> > +      .arg   = "ALG",
> > +      .flags = 0,
> > +      .doc   =
> > +   N_("Bank of PCRs used to authorize key release: "
> > +      "SHA1, SHA256, SHA384, or SHA512. (default: SHA256)"),
> > +      .group = 0
> > +    },
> > +    {
> > +      .name = "tpm2-keyfile",
> > +      .key   = GRUB_PROTECT_OPT_TPM2_KEYFILE,
> > +      .arg   = "FILE",
> > +      .flags = 0,
> > +      .doc   =
> > +   N_("Path to a file that contains the cleartext key to protect."),
> > +      .group = 0
> > +    },
> > +    {
> > +      .name = "tpm2-outfile",
> > +      .key   = GRUB_PROTECT_OPT_TPM2_OUTFILE,
> > +      .arg   = "FILE",
> > +      .flags = 0,
> > +      .doc   =
> > +   N_("Path to the file that will contain the key after sealing (must be "
> > +      "accessible to GRUB during boot)."),
> > +      .group = 0
> > +    },
> > +    {
> > +      .name = "tpm2-srk",
> > +      .key   = GRUB_PROTECT_OPT_TPM2_SRK,
> > +      .arg   = "NUM",
> > +      .flags = 0,
> > +      .doc   =
> > +   N_("The SRK handle if the SRK is to be made persistent."),
> > +      .group = 0
> > +    },
> > +    {
> > +      .name = "tpm2-asymmetric",
> > +      .key   = GRUB_PROTECT_OPT_TPM2_ASYMMETRIC,
> > +      .arg   = "TYPE",
> > +      .flags = 0,
> > +      .doc   =
> > +   N_("The type of SRK: RSA (RSA2048) and ECC (ECC_NIST_P256)."
> > +      "(default: ECC)"),
> > +      .group = 0
> > +    },
> > +    {
> > +      .name = "tpm2-evict",
> > +      .key   = GRUB_PROTECT_OPT_TPM2_EVICT,
> > +      .arg   = NULL,
> > +      .flags = 0,
> > +      .doc   =
> > +   N_("Evict a previously persisted SRK from the TPM, if any."),
> > +      .group = 0
> > +    },
> > +    {
> > +      .name = "tpm2key",
> > +      .key   = GRUB_PROTECT_OPT_TPM2_TPM2KEY,
> > +      .arg   = NULL,
> > +      .flags = 0,
> > +      .doc   =
> > +   N_("Use TPM 2.0 Key File format instead of the raw format."),
> > +      .group = 0
> > +    },
> > +    /* End of list */
> > +    { 0, 0, 0, 0, 0, 0 }
> > +  };
> > +
> > +static int grub_protector_tpm2_fd = -1;
> 
> I would prefer if it is not global...
> 
It's a bit tricky. 'grub_protector_tpm2_fd' is mainly for the command
submission function, grub_tcg2_submit_command(), which only expects
the TPM2 command input and output, so the variable is made global to
avoid adding additional parameters to grub_tcg2_submit_command().

> > +static grub_err_t
> > +grub_protect_read_file (const char *filepath, void **buffer,
> > +                   size_t *buffer_size)
> > +{
> > +  grub_err_t err;
> > +  FILE *f;
> > +  long len;
> > +  void *buf;
> > +
> > +  f = fopen (filepath, "rb");
> > +  if (f == NULL)
> > +    return GRUB_ERR_FILE_NOT_FOUND;
> > +
> > +  if (fseek (f, 0, SEEK_END))
> > +    {
> > +       err = GRUB_ERR_FILE_READ_ERROR;
> > +       goto exit1;
> > +    }
> > +
> > +  len = ftell (f);
> > +  if (len <= 0)
> > +    {
> > +       err = GRUB_ERR_FILE_READ_ERROR;
> > +       goto exit1;
> > +    }
> > +
> > +  rewind (f);
> > +
> > +  buf = grub_malloc (len);
> > +  if (buf == NULL)
> > +    {
> > +       err = GRUB_ERR_OUT_OF_MEMORY;
> > +       goto exit1;
> > +    }
> > +
> > +  if (fread (buf, len, 1, f) != 1)
> > +    {
> > +       err = GRUB_ERR_FILE_READ_ERROR;
> > +       goto exit2;
> > +    }
> > +
> > +  *buffer = buf;
> > +  *buffer_size = len;
> > +
> > +  buf = NULL;
> > +  err = GRUB_ERR_NONE;
> > +
> > +exit2:
> > +  grub_free (buf);
> > +
> > +exit1:
> 
> Missing spaces before labels.
> 
Will fix them in the next version.

> > +  fclose (f);
> > +
> > +  return err;
> > +}
> > +
> > +static grub_err_t
> > +grub_protect_write_file (const char *filepath, void *buffer, size_t 
> > buffer_size)
> > +{
> > +  grub_err_t err;
> > +  FILE *f;
> > +
> > +  f = fopen (filepath, "wb");
> > +  if (f == NULL)
> > +    return GRUB_ERR_FILE_NOT_FOUND;
> > +
> > +  if (fwrite (buffer, buffer_size, 1, f) != 1)
> > +  {
> > +    err = GRUB_ERR_WRITE_ERROR;
> > +    goto exit1;
> > +  }
> > +
> > +  err = GRUB_ERR_NONE;
> > +
> > +exit1:
> 
> Ditto and below please...
> 
> > +  fclose (f);
> > +
> > +  return err;
> > +}
> 
> [...]
> 
> > +static grub_err_t
> > +grub_protect_tpm2_get_policy_digest (struct grub_protect_args *args,
> > +                                TPM2B_DIGEST *digest)
> > +{
> > +  TPM_RC rc;
> > +  TPML_PCR_SELECTION pcr_sel = {
> > +    .count = 1,
> > +    .pcrSelections = {
> > +      {
> > +   .hash = args->tpm2_bank,
> > +   .sizeOfSelect = 3,
> > +   .pcrSelect = { 0 }
> > +      },
> > +    }
> > +  };
> > +  TPML_PCR_SELECTION pcr_sel_out = { 0 };
> > +  TPML_DIGEST pcr_values = { 0 };
> > +  TPM2B_DIGEST pcr_digest = { 0 };
> > +  grub_size_t pcr_digest_len;
> > +  TPM2B_MAX_BUFFER pcr_concat = { 0 };
> > +  grub_size_t pcr_concat_len;
> > +  grub_uint8_t *pcr_cursor;
> > +  TPM2B_NONCE nonce = { 0 };
> > +  TPM2B_ENCRYPTED_SECRET salt = { 0 };
> > +  TPMT_SYM_DEF symmetric = { 0 };
> > +  TPMI_SH_AUTH_SESSION session = 0;
> > +  TPM2B_DIGEST policy_digest = { 0 };
> > +  grub_uint8_t i;
> > +  grub_err_t err;
> > +
> > +  /* PCR Read */
> > +  for (i = 0; i < args->tpm2_pcr_count; i++)
> > +    TPMS_PCR_SELECTION_SelectPCR (&pcr_sel.pcrSelections[0], 
> > args->tpm2_pcrs[i]);
> > +
> > +  rc = TPM2_PCR_Read (NULL, &pcr_sel, NULL, &pcr_sel_out, &pcr_values, 
> > NULL);
> > +  if (rc != TPM_RC_SUCCESS)
> > +    {
> > +      fprintf (stderr, _("Failed to read PCRs (TPM2_PCR_Read: 0x%x).\n"), 
> > rc);
> > +      return GRUB_ERR_BAD_DEVICE;
> > +    }
> > +
> > +  if ((pcr_sel_out.count != pcr_sel.count) ||
> > +       (pcr_sel.pcrSelections[0].sizeOfSelect !=
> > +   pcr_sel_out.pcrSelections[0].sizeOfSelect))
> > +    {
> > +      fprintf (stderr, _("Could not read all the specified PCRs.\n"));
> > +      return GRUB_ERR_BAD_DEVICE;
> > +    }
> > +
> > +  /* Compute PCR Digest */
> > +  switch (args->tpm2_bank)
> > +    {
> > +    case TPM_ALG_SHA1:
> > +      pcr_digest_len = TPM_SHA1_DIGEST_SIZE;
> > +      break;
> > +    case TPM_ALG_SHA256:
> > +      pcr_digest_len = TPM_SHA256_DIGEST_SIZE;
> > +      break;
> > +    case TPM_ALG_SHA384:
> > +      pcr_digest_len = TPM_SHA384_DIGEST_SIZE;
> > +      break;
> > +    case TPM_ALG_SHA512:
> > +      pcr_digest_len = TPM_SHA512_DIGEST_SIZE;
> > +      break;
> > +    default:
> > +      return GRUB_ERR_BAD_ARGUMENT;
> > +    }
> > +
> > +  pcr_concat_len = pcr_digest_len * args->tpm2_pcr_count;
> > +  if (pcr_concat_len > TPM_MAX_DIGEST_BUFFER)
> > +    {
> > +      fprintf (stderr, _("PCR concatenation buffer not enough.\n"));
> > +      return GRUB_ERR_OUT_OF_RANGE;
> > +    }
> > +
> > +  pcr_cursor = pcr_concat.buffer;
> > +  for (i = 0; i < args->tpm2_pcr_count; i++)
> > +    {
> > +      if (pcr_values.digests[i].size != pcr_digest_len)
> > +   {
> > +     fprintf (stderr,
> > +              _("Bad PCR value size: expected %" PRIuGRUB_SIZE " bytes but 
> > got %u bytes.\n"),
> 
> You cannot use PRIuGRUB_SIZE within _() macro.
> 
Will fix it in the next version.

Gary Lin

> > +              pcr_digest_len, pcr_values.digests[i].size);
> > +     return GRUB_ERR_BAD_ARGUMENT;
> > +   }
> 
> Daniel