grub2/grub-2.00-no-insmod-on-sb.patch
2012-08-15 09:58:04 -04:00

93 lines
2.7 KiB
Diff

From 7a65d7b558974c89f19afaf0d78b54dc0327f56c Mon Sep 17 00:00:00 2001
From: Matthew Garrett <mjg@redhat.com>
Date: Wed, 15 Aug 2012 09:53:05 -0400
Subject: [PATCH] Don't permit insmod on secure boot
---
grub-core/kern/corecmd.c | 9 +++++++++
grub-core/kern/efi/efi.c | 28 ++++++++++++++++++++++++++++
include/grub/efi/efi.h | 1 +
3 files changed, 38 insertions(+)
diff --git a/grub-core/kern/corecmd.c b/grub-core/kern/corecmd.c
index eec575c..3df9dbd 100644
--- a/grub-core/kern/corecmd.c
+++ b/grub-core/kern/corecmd.c
@@ -28,6 +28,10 @@
#include <grub/command.h>
#include <grub/i18n.h>
+#ifdef GRUB_MACHINE_EFI
+#include <grub/efi/efi.h>
+#endif
+
/* set ENVVAR=VALUE */
static grub_err_t
grub_core_cmd_set (struct grub_command *cmd __attribute__ ((unused)),
@@ -81,6 +85,11 @@ grub_core_cmd_insmod (struct grub_command *cmd __attribute__ ((unused)),
{
grub_dl_t mod;
+#ifdef GRUB_MACHINE_EFI
+ if (grub_efi_secure_boot())
+ return grub_error (GRUB_ERR_ACCESS_DENIED, N_("Secure Boot forbids insmod"));
+#endif
+
if (argc == 0)
return grub_error (GRUB_ERR_BAD_ARGUMENT, N_("one argument expected"));
diff --git a/grub-core/kern/efi/efi.c b/grub-core/kern/efi/efi.c
index 820968f..ad7aa8d 100644
--- a/grub-core/kern/efi/efi.c
+++ b/grub-core/kern/efi/efi.c
@@ -259,6 +259,34 @@ grub_efi_set_variable(const char *var, const grub_efi_guid_t *guid,
return grub_error (GRUB_ERR_IO, "could not set EFI variable `%s'", var);
}
+grub_efi_boolean_t
+grub_efi_secure_boot (void)
+{
+ grub_efi_guid_t efi_var_guid = GRUB_EFI_GLOBAL_VARIABLE_GUID;
+ grub_size_t datasize;
+ char *secure_boot = NULL;
+ char *setup_mode = NULL;
+ grub_efi_boolean_t ret = 0;
+
+ secure_boot = grub_efi_get_variable("SecureBoot", &efi_var_guid, &datasize);
+
+ if (datasize != 1 || !secure_boot)
+ goto out;
+
+ setup_mode = grub_efi_get_variable("SetupMode", &efi_var_guid, &datasize);
+
+ if (datasize != 1 || !setup_mode)
+ goto out;
+
+ if (*secure_boot && !*setup_mode)
+ ret = 1;
+
+ out:
+ grub_free (secure_boot);
+ grub_free (setup_mode);
+ return ret;
+}
+
#pragma GCC diagnostic ignored "-Wcast-align"
/* Search the mods section from the PE32/PE32+ image. This code uses
diff --git a/include/grub/efi/efi.h b/include/grub/efi/efi.h
index 9370fd5..a000c38 100644
--- a/include/grub/efi/efi.h
+++ b/include/grub/efi/efi.h
@@ -72,6 +72,7 @@ EXPORT_FUNC (grub_efi_set_variable) (const char *var,
const grub_efi_guid_t *guid,
void *data,
grub_size_t datasize);
+grub_efi_boolean_t EXPORT_FUNC (grub_efi_secure_boot) (void);
int
EXPORT_FUNC (grub_efi_compare_device_paths) (const grub_efi_device_path_t *dp1,
const grub_efi_device_path_t *dp2);
--
1.7.11.2