grub2/grub2-secureboot-no-insmod-on-sb.patch

From 29c89e27805f7a6a22bce11ed9bb430e19c972a9 Mon Sep 17 00:00:00 2001
From: Colin Watson <cjwatson@ubuntu.com>
Date: Tue, 23 Oct 2012 10:40:49 -0400
Subject: [PATCH 449/482] Don't allow insmod when secure boot is enabled.

References: fate#314485
Patch-Mainline: no

Signed-off-by: Michael Chang <mchang@suse.com>
---
 grub-core/kern/dl.c      | 17 +++++++++++++++++
 grub-core/kern/efi/efi.c | 28 ++++++++++++++++++++++++++++
 include/grub/efi/efi.h   |  1 +
 3 files changed, 46 insertions(+)

Index: grub-2.04~rc1/grub-core/kern/dl.c
===================================================================
--- grub-2.04~rc1.orig/grub-core/kern/dl.c
+++ grub-2.04~rc1/grub-core/kern/dl.c
@@ -38,6 +38,10 @@
 #define GRUB_MODULES_MACHINE_READONLY
 #endif
 
+#ifdef GRUB_MACHINE_EFI
+#include <grub/efi/efi.h>
+#endif
+
 
 
 #pragma GCC diagnostic ignored "-Wcast-align"
@@ -688,6 +692,19 @@ grub_dl_load_file (const char *filename)
 
   grub_boot_time ("Loading module %s", filename);
 
+#ifdef GRUB_MACHINE_EFI
+  if (grub_efi_secure_boot ())
+    {
+#if 0
+      /* This is an error, but grub2-mkconfig still generates a pile of
+       * insmod commands, so emitting it would be mostly just obnoxious. */
+      grub_error (GRUB_ERR_ACCESS_DENIED,
+		  "Secure Boot forbids loading module from %s", filename);
+#endif
+      return 0;
+    }
+#endif
+
   file = grub_file_open (filename, GRUB_FILE_TYPE_GRUB_MODULE);
   if (! file)
     return 0;
Index: grub-2.04~rc1/grub-core/kern/efi/efi.c
===================================================================
--- grub-2.04~rc1.orig/grub-core/kern/efi/efi.c
+++ grub-2.04~rc1/grub-core/kern/efi/efi.c
@@ -273,6 +273,34 @@ grub_efi_get_variable (const char *var,
   return NULL;
 }
 
+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
Index: grub-2.04~rc1/include/grub/efi/efi.h
===================================================================
--- grub-2.04~rc1.orig/include/grub/efi/efi.h
+++ grub-2.04~rc1/include/grub/efi/efi.h
@@ -85,6 +85,7 @@ EXPORT_FUNC (grub_efi_set_variable) (con
 				     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);