[PATCH v3 04/19] commands/tpm: Rename tpm module to tpm_verifier

[Sergii Dmytruk]

From: Aleksandr Burmashev <alexander.burmashev@oracle.com>

This avoids naming collision with TPM TIS and CRB driver introduced
by subsequent patch and characterizes the functionality of the module
better.

Signed-off-by: Daniel Kiper <daniel.kiper@oracle.com>
Signed-off-by: Sergii Dmytruk <sergii.dmytruk@3mdeb.com>
---
 docs/grub.texi                    |  21 +++---
 grub-core/Makefile.core.def       |   4 +-
 grub-core/commands/tpm_verifier.c | 102 ++++++++++++++++++++++++++++++
 3 files changed, 115 insertions(+), 12 deletions(-)
 create mode 100644 grub-core/commands/tpm_verifier.c

diff --git a/docs/grub.texi b/docs/grub.texi
index 200e747af..5355ca356 100644
--- a/docs/grub.texi
+++ b/docs/grub.texi
@@ -4136,7 +4136,7 @@ Modules can be loaded via the @command{insmod} 
(@pxref{insmod}) command.
 * tftp_module::
 * tga_module::
 * time_module::
-* tpm_module::
+* tpm_verifier_module::
 * tr_module::
 * trig_module::
 * true_module::
@@ -5702,8 +5702,8 @@ image files in GRUB.
 This module provides support for the @command{time} command to measure the
 time taken by a given command and output it to the terminal.
 
-@node tpm_module
-@section tpm
+@node tpm_verifier_module
+@section tpm_verifier
 This module provides support for interacting with a Trusted Platform Module
 (TPM) with GRUB to perform Measured Boot. @xref{Measured Boot} for more
 information.
@@ -8770,10 +8770,10 @@ grub-mkimage -O x86_64-efi -o grubx64.efi -p 
'(tftp)/grub' --sbat sbat.csv efine
 @node Measured Boot
 @section Measuring boot components
 
-If the tpm module is loaded and the platform has a Trusted Platform Module
-installed, GRUB will log each command executed and each file loaded into the
-TPM event log and extend the PCR values in the TPM correspondingly. All events
-will be logged into the PCR described below with a type of EV_IPL and an
+If the tpm_verifier module is loaded and the platform has a Trusted Platform
+Module installed, GRUB will log each command executed and each file loaded into
+the TPM event log and extend the PCR values in the TPM correspondingly. All
+events will be logged into the PCR described below with a type of EV_IPL and an
 event description as described below.
 
 @multitable @columnfractions 0.3 0.1 0.6
@@ -8798,9 +8798,10 @@ corresponding to the filename.
 
 GRUB will not measure its own @file{core.img} - it is expected that firmware
 will carry this out. GRUB will also not perform any measurements until the
-tpm module is loaded. As such it is recommended that the tpm module be built
-into @file{core.img} in order to avoid a potential gap in measurement between
-@file{core.img} being loaded and the tpm module being loaded.
+tpm_verifier module is loaded. As such it is recommended that the tpm_verifier
+module be built into @file{core.img} in order to avoid a potential gap in
+measurement between @file{core.img} being loaded and the tpm_verifier module
+being loaded.
 
 Measured boot is currently only supported on EFI and IBM IEEE1275 PowerPC
 platforms.
diff --git a/grub-core/Makefile.core.def b/grub-core/Makefile.core.def
index adadd1365..363b3ff12 100644
--- a/grub-core/Makefile.core.def
+++ b/grub-core/Makefile.core.def
@@ -2560,8 +2560,8 @@ module = {
 };
 
 module = {
-  name = tpm;
-  common = commands/tpm.c;
+  name = tpm_verifier;
+  common = commands/tpm_verifier.c;
   efi = commands/efi/tpm.c;
   enable = efi;
 };
diff --git a/grub-core/commands/tpm_verifier.c 
b/grub-core/commands/tpm_verifier.c
new file mode 100644
index 000000000..f72ce6730
--- /dev/null
+++ b/grub-core/commands/tpm_verifier.c
@@ -0,0 +1,102 @@
+/*
+ *  GRUB  --  GRand Unified Bootloader
+ *  Copyright (C) 2018  Free Software Foundation, Inc.
+ *
+ *  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/>.
+ *
+ *  Core TPM support code.
+ */
+
+#include <grub/err.h>
+#include <grub/i18n.h>
+#include <grub/misc.h>
+#include <grub/mm.h>
+#include <grub/tpm.h>
+#include <grub/term.h>
+#include <grub/verify.h>
+#include <grub/dl.h>
+
+GRUB_MOD_LICENSE ("GPLv3+");
+
+grub_err_t
+grub_tpm_measure (unsigned char *buf, grub_size_t size, grub_uint8_t pcr,
+                 const char *description)
+{
+  return grub_tpm_log_event (buf, size, pcr, description);
+}
+
+static grub_err_t
+grub_tpm_verify_init (grub_file_t io,
+                     enum grub_file_type type __attribute__ ((unused)),
+                     void **context, enum grub_verify_flags *flags)
+{
+  *context = io->name;
+  *flags |= GRUB_VERIFY_FLAGS_SINGLE_CHUNK;
+  return GRUB_ERR_NONE;
+}
+
+static grub_err_t
+grub_tpm_verify_write (void *context, void *buf, grub_size_t size)
+{
+  grub_tpm_measure (buf, size, GRUB_BINARY_PCR, context);
+  return GRUB_ERR_NONE;
+}
+
+static grub_err_t
+grub_tpm_verify_string (char *str, enum grub_verify_string_type type)
+{
+  const char *prefix = NULL;
+  char *description;
+
+  switch (type)
+    {
+    case GRUB_VERIFY_KERNEL_CMDLINE:
+      prefix = "kernel_cmdline: ";
+      break;
+    case GRUB_VERIFY_MODULE_CMDLINE:
+      prefix = "module_cmdline: ";
+      break;
+    case GRUB_VERIFY_COMMAND:
+      prefix = "grub_cmd: ";
+      break;
+    }
+  description = grub_malloc (grub_strlen (str) + grub_strlen (prefix) + 1);
+  if (!description)
+    return GRUB_ERR_NONE;
+  grub_memcpy (description, prefix, grub_strlen (prefix));
+  grub_memcpy (description + grub_strlen (prefix), str,
+              grub_strlen (str) + 1);
+
+  grub_tpm_measure ((unsigned char *) str, grub_strlen (str), GRUB_STRING_PCR,
+                    description);
+  grub_free (description);
+  return GRUB_ERR_NONE;
+}
+
+struct grub_file_verifier grub_tpm_verifier = {
+  .name = "tpm_verifier",
+  .init = grub_tpm_verify_init,
+  .write = grub_tpm_verify_write,
+  .verify_string = grub_tpm_verify_string,
+};
+
+GRUB_MOD_INIT (tpm_verifier)
+{
+  grub_verifier_register (&grub_tpm_verifier);
+}
+
+GRUB_MOD_FINI (tpm_verifier)
+{
+  grub_verifier_unregister (&grub_tpm_verifier);
+}
-- 
2.47.1