From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Peter Jones <pjones@redhat.com>
Date: Tue, 6 Oct 2015 16:09:25 -0400
Subject: [PATCH] Make any of the loaders that link in efi mode honor secure
 boot.

And in this case "honor" means "even if somebody does link this in, they
won't register commands if SB is enabled."

Signed-off-by: Peter Jones <pjones@redhat.com>
---
 grub-core/Makefile.core.def        |  1 +
 grub-core/commands/iorw.c          |  7 +++++
 grub-core/commands/memrw.c         |  7 +++++
 grub-core/kern/dl.c                |  1 +
 grub-core/kern/efi/efi.c           | 34 --------------------
 grub-core/kern/efi/sb.c            | 64 ++++++++++++++++++++++++++++++++++++++
 grub-core/loader/efi/appleloader.c |  7 +++++
 grub-core/loader/efi/chainloader.c |  1 +
 grub-core/loader/i386/bsd.c        |  7 +++++
 grub-core/loader/i386/linux.c      |  7 +++++
 grub-core/loader/i386/pc/linux.c   |  7 +++++
 grub-core/loader/multiboot.c       |  7 +++++
 grub-core/loader/xnu.c             |  7 +++++
 include/grub/efi/efi.h             |  1 -
 include/grub/efi/sb.h              | 29 +++++++++++++++++
 include/grub/ia64/linux.h          |  0
 include/grub/mips/linux.h          |  0
 include/grub/powerpc/linux.h       |  0
 include/grub/sparc64/linux.h       |  0
 grub-core/Makefile.am              |  1 +
 20 files changed, 153 insertions(+), 35 deletions(-)
 create mode 100644 grub-core/kern/efi/sb.c
 create mode 100644 include/grub/efi/sb.h
 create mode 100644 include/grub/ia64/linux.h
 create mode 100644 include/grub/mips/linux.h
 create mode 100644 include/grub/powerpc/linux.h
 create mode 100644 include/grub/sparc64/linux.h

diff --git a/grub-core/Makefile.core.def b/grub-core/Makefile.core.def
index 0b4b0c212..e92a7ef32 100644
--- a/grub-core/Makefile.core.def
+++ b/grub-core/Makefile.core.def
@@ -195,6 +195,7 @@ kernel = {
   i386_multiboot = kern/i386/pc/acpi.c;
   i386_coreboot = kern/acpi.c;
   i386_multiboot = kern/acpi.c;
+  common = kern/efi/sb.c;
 
   x86 = kern/i386/tsc.c;
   x86 = kern/i386/tsc_pit.c;
diff --git a/grub-core/commands/iorw.c b/grub-core/commands/iorw.c
index a0c164e54..41a7f3f04 100644
--- a/grub-core/commands/iorw.c
+++ b/grub-core/commands/iorw.c
@@ -23,6 +23,7 @@
 #include <grub/env.h>
 #include <grub/cpu/io.h>
 #include <grub/i18n.h>
+#include <grub/efi/sb.h>
 
 GRUB_MOD_LICENSE ("GPLv3+");
 
@@ -118,6 +119,9 @@ grub_cmd_write (grub_command_t cmd, int argc, char **argv)
 
 GRUB_MOD_INIT(memrw)
 {
+  if (grub_efi_secure_boot())
+    return;
+
   cmd_read_byte =
     grub_register_extcmd ("inb", grub_cmd_read, 0,
 			  N_("PORT"), N_("Read 8-bit value from PORT."),
@@ -146,6 +150,9 @@ GRUB_MOD_INIT(memrw)
 
 GRUB_MOD_FINI(memrw)
 {
+  if (grub_efi_secure_boot())
+    return;
+
   grub_unregister_extcmd (cmd_read_byte);
   grub_unregister_extcmd (cmd_read_word);
   grub_unregister_extcmd (cmd_read_dword);
diff --git a/grub-core/commands/memrw.c b/grub-core/commands/memrw.c
index 98769eadb..088cbe9e2 100644
--- a/grub-core/commands/memrw.c
+++ b/grub-core/commands/memrw.c
@@ -22,6 +22,7 @@
 #include <grub/extcmd.h>
 #include <grub/env.h>
 #include <grub/i18n.h>
+#include <grub/efi/sb.h>
 
 GRUB_MOD_LICENSE ("GPLv3+");
 
@@ -120,6 +121,9 @@ grub_cmd_write (grub_command_t cmd, int argc, char **argv)
 
 GRUB_MOD_INIT(memrw)
 {
+  if (grub_efi_secure_boot())
+    return;
+
   cmd_read_byte =
     grub_register_extcmd ("read_byte", grub_cmd_read, 0,
 			  N_("ADDR"), N_("Read 8-bit value from ADDR."),
@@ -148,6 +152,9 @@ GRUB_MOD_INIT(memrw)
 
 GRUB_MOD_FINI(memrw)
 {
+  if (grub_efi_secure_boot())
+    return;
+
   grub_unregister_extcmd (cmd_read_byte);
   grub_unregister_extcmd (cmd_read_word);
   grub_unregister_extcmd (cmd_read_dword);
diff --git a/grub-core/kern/dl.c b/grub-core/kern/dl.c
index 04e804d16..621070918 100644
--- a/grub-core/kern/dl.c
+++ b/grub-core/kern/dl.c
@@ -32,6 +32,7 @@
 #include <grub/env.h>
 #include <grub/cache.h>
 #include <grub/i18n.h>
+#include <grub/efi/sb.h>
 
 /* Platforms where modules are in a readonly area of memory.  */
 #if defined(GRUB_MACHINE_QEMU)
diff --git a/grub-core/kern/efi/efi.c b/grub-core/kern/efi/efi.c
index 91129e335..708581fcb 100644
--- a/grub-core/kern/efi/efi.c
+++ b/grub-core/kern/efi/efi.c
@@ -273,40 +273,6 @@ grub_efi_get_variable (const char *var, const grub_efi_guid_t *guid,
   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)
-    {
-      grub_dprintf ("secureboot", "No SecureBoot variable\n");
-      goto out;
-    }
-  grub_dprintf ("secureboot", "SecureBoot: %d\n", *secure_boot);
-
-  setup_mode = grub_efi_get_variable("SetupMode", &efi_var_guid, &datasize);
-  if (datasize != 1 || !setup_mode)
-    {
-      grub_dprintf ("secureboot", "No SetupMode variable\n");
-      goto out;
-    }
-  grub_dprintf ("secureboot", "SetupMode: %d\n", *setup_mode);
-
-  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/grub-core/kern/efi/sb.c b/grub-core/kern/efi/sb.c
new file mode 100644
index 000000000..d74778b0c
--- /dev/null
+++ b/grub-core/kern/efi/sb.c
@@ -0,0 +1,64 @@
+/*
+ *  GRUB  --  GRand Unified Bootloader
+ *  Copyright (C) 2014 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/>.
+ */
+
+#include <grub/err.h>
+#include <grub/mm.h>
+#include <grub/types.h>
+#include <grub/cpu/linux.h>
+#include <grub/efi/efi.h>
+#include <grub/efi/pe32.h>
+#include <grub/efi/linux.h>
+#include <grub/efi/sb.h>
+
+int
+grub_efi_secure_boot (void)
+{
+#ifdef GRUB_MACHINE_EFI
+  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)
+    {
+      grub_dprintf ("secureboot", "No SecureBoot variable\n");
+      goto out;
+    }
+  grub_dprintf ("secureboot", "SecureBoot: %d\n", *secure_boot);
+
+  setup_mode = grub_efi_get_variable("SetupMode", &efi_var_guid, &datasize);
+  if (datasize != 1 || !setup_mode)
+    {
+      grub_dprintf ("secureboot", "No SetupMode variable\n");
+      goto out;
+    }
+  grub_dprintf ("secureboot", "SetupMode: %d\n", *setup_mode);
+
+  if (*secure_boot && !*setup_mode)
+    ret = 1;
+
+ out:
+  grub_free (secure_boot);
+  grub_free (setup_mode);
+  return ret;
+#else
+  return 0;
+#endif
+}
diff --git a/grub-core/loader/efi/appleloader.c b/grub-core/loader/efi/appleloader.c
index 74888c463..69c2a10d3 100644
--- a/grub-core/loader/efi/appleloader.c
+++ b/grub-core/loader/efi/appleloader.c
@@ -24,6 +24,7 @@
 #include <grub/misc.h>
 #include <grub/efi/api.h>
 #include <grub/efi/efi.h>
+#include <grub/efi/sb.h>
 #include <grub/command.h>
 #include <grub/i18n.h>
 
@@ -227,6 +228,9 @@ static grub_command_t cmd;
 
 GRUB_MOD_INIT(appleloader)
 {
+  if (grub_efi_secure_boot())
+    return;
+
   cmd = grub_register_command ("appleloader", grub_cmd_appleloader,
 			       N_("[OPTS]"),
 			       /* TRANSLATORS: This command is used on EFI to
@@ -238,5 +242,8 @@ GRUB_MOD_INIT(appleloader)
 
 GRUB_MOD_FINI(appleloader)
 {
+  if (grub_efi_secure_boot())
+    return;
+
   grub_unregister_command (cmd);
 }
diff --git a/grub-core/loader/efi/chainloader.c b/grub-core/loader/efi/chainloader.c
index af2189619..5cd9b6e08 100644
--- a/grub-core/loader/efi/chainloader.c
+++ b/grub-core/loader/efi/chainloader.c
@@ -34,6 +34,7 @@
 #include <grub/efi/disk.h>
 #include <grub/efi/pe32.h>
 #include <grub/efi/linux.h>
+#include <grub/efi/sb.h>
 #include <grub/command.h>
 #include <grub/i18n.h>
 #include <grub/net.h>
diff --git a/grub-core/loader/i386/bsd.c b/grub-core/loader/i386/bsd.c
index 7f96515da..87709aa23 100644
--- a/grub-core/loader/i386/bsd.c
+++ b/grub-core/loader/i386/bsd.c
@@ -38,6 +38,7 @@
 #ifdef GRUB_MACHINE_PCBIOS
 #include <grub/machine/int.h>
 #endif
+#include <grub/efi/sb.h>
 
 GRUB_MOD_LICENSE ("GPLv3+");
 
@@ -2124,6 +2125,9 @@ static grub_command_t cmd_netbsd_module_elf, cmd_openbsd_ramdisk;
 
 GRUB_MOD_INIT (bsd)
 {
+  if (grub_efi_secure_boot())
+    return;
+
   /* Net and OpenBSD kernels are often compressed.  */
   grub_dl_load ("gzio");
 
@@ -2163,6 +2167,9 @@ GRUB_MOD_INIT (bsd)
 
 GRUB_MOD_FINI (bsd)
 {
+  if (grub_efi_secure_boot())
+    return;
+
   grub_unregister_extcmd (cmd_freebsd);
   grub_unregister_extcmd (cmd_openbsd);
   grub_unregister_extcmd (cmd_netbsd);
diff --git a/grub-core/loader/i386/linux.c b/grub-core/loader/i386/linux.c
index f7186be40..c84747ea8 100644
--- a/grub-core/loader/i386/linux.c
+++ b/grub-core/loader/i386/linux.c
@@ -35,6 +35,7 @@
 #include <grub/i18n.h>
 #include <grub/lib/cmdline.h>
 #include <grub/linux.h>
+#include <grub/efi/sb.h>
 
 GRUB_MOD_LICENSE ("GPLv3+");
 
@@ -1156,6 +1157,9 @@ static grub_command_t cmd_linux, cmd_initrd;
 
 GRUB_MOD_INIT(linux)
 {
+  if (grub_efi_secure_boot())
+    return;
+
   cmd_linux = grub_register_command ("linux", grub_cmd_linux,
 				     0, N_("Load Linux."));
   cmd_initrd = grub_register_command ("initrd", grub_cmd_initrd,
@@ -1165,6 +1169,9 @@ GRUB_MOD_INIT(linux)
 
 GRUB_MOD_FINI(linux)
 {
+  if (grub_efi_secure_boot())
+    return;
+
   grub_unregister_command (cmd_linux);
   grub_unregister_command (cmd_initrd);
 }
diff --git a/grub-core/loader/i386/pc/linux.c b/grub-core/loader/i386/pc/linux.c
index caa76bee8..783a3cd93 100644
--- a/grub-core/loader/i386/pc/linux.c
+++ b/grub-core/loader/i386/pc/linux.c
@@ -35,6 +35,7 @@
 #include <grub/i386/floppy.h>
 #include <grub/lib/cmdline.h>
 #include <grub/linux.h>
+#include <grub/efi/sb.h>
 
 GRUB_MOD_LICENSE ("GPLv3+");
 
@@ -480,6 +481,9 @@ static grub_command_t cmd_linux, cmd_linux16, cmd_initrd, cmd_initrd16;
 
 GRUB_MOD_INIT(linux16)
 {
+  if (grub_efi_secure_boot())
+    return;
+
   cmd_linux =
     grub_register_command ("linux", grub_cmd_linux,
 			   0, N_("Load Linux."));
@@ -497,6 +501,9 @@ GRUB_MOD_INIT(linux16)
 
 GRUB_MOD_FINI(linux16)
 {
+  if (grub_efi_secure_boot())
+    return;
+
   grub_unregister_command (cmd_linux);
   grub_unregister_command (cmd_linux16);
   grub_unregister_command (cmd_initrd);
diff --git a/grub-core/loader/multiboot.c b/grub-core/loader/multiboot.c
index 40c67e824..26df46a41 100644
--- a/grub-core/loader/multiboot.c
+++ b/grub-core/loader/multiboot.c
@@ -50,6 +50,7 @@
 #include <grub/video.h>
 #include <grub/memory.h>
 #include <grub/i18n.h>
+#include <grub/efi/sb.h>
 
 GRUB_MOD_LICENSE ("GPLv3+");
 
@@ -446,6 +447,9 @@ static grub_command_t cmd_multiboot, cmd_module;
 
 GRUB_MOD_INIT(multiboot)
 {
+  if (grub_efi_secure_boot())
+    return;
+
   cmd_multiboot =
 #ifdef GRUB_USE_MULTIBOOT2
     grub_register_command ("multiboot2", grub_cmd_multiboot,
@@ -466,6 +470,9 @@ GRUB_MOD_INIT(multiboot)
 
 GRUB_MOD_FINI(multiboot)
 {
+  if (grub_efi_secure_boot())
+    return;
+
   grub_unregister_command (cmd_multiboot);
   grub_unregister_command (cmd_module);
 }
diff --git a/grub-core/loader/xnu.c b/grub-core/loader/xnu.c
index c9885b1bc..df8dfdb4b 100644
--- a/grub-core/loader/xnu.c
+++ b/grub-core/loader/xnu.c
@@ -33,6 +33,7 @@
 #include <grub/extcmd.h>
 #include <grub/env.h>
 #include <grub/i18n.h>
+#include <grub/efi/sb.h>
 
 GRUB_MOD_LICENSE ("GPLv3+");
 
@@ -1469,6 +1470,9 @@ static grub_extcmd_t cmd_splash;
 
 GRUB_MOD_INIT(xnu)
 {
+  if (grub_efi_secure_boot())
+    return;
+
   cmd_kernel = grub_register_command ("xnu_kernel", grub_cmd_xnu_kernel, 0,
 				      N_("Load XNU image."));
   cmd_kernel64 = grub_register_command ("xnu_kernel64", grub_cmd_xnu_kernel64,
@@ -1509,6 +1513,9 @@ GRUB_MOD_INIT(xnu)
 
 GRUB_MOD_FINI(xnu)
 {
+  if (grub_efi_secure_boot())
+    return;
+
 #ifndef GRUB_MACHINE_EMU
   grub_unregister_command (cmd_resume);
 #endif
diff --git a/include/grub/efi/efi.h b/include/grub/efi/efi.h
index 1061aee97..39480b386 100644
--- a/include/grub/efi/efi.h
+++ b/include/grub/efi/efi.h
@@ -85,7 +85,6 @@ 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);
diff --git a/include/grub/efi/sb.h b/include/grub/efi/sb.h
new file mode 100644
index 000000000..9629fbb0f
--- /dev/null
+++ b/include/grub/efi/sb.h
@@ -0,0 +1,29 @@
+/* sb.h - declare functions for EFI Secure Boot support */
+/*
+ *  GRUB  --  GRand Unified Bootloader
+ *  Copyright (C) 2006,2007,2008,2009  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/>.
+ */
+
+#ifndef GRUB_EFI_SB_HEADER
+#define GRUB_EFI_SB_HEADER	1
+
+#include <grub/types.h>
+#include <grub/dl.h>
+
+/* Functions.  */
+int EXPORT_FUNC (grub_efi_secure_boot) (void);
+
+#endif /* ! GRUB_EFI_SB_HEADER */
diff --git a/include/grub/ia64/linux.h b/include/grub/ia64/linux.h
new file mode 100644
index 000000000..e69de29bb
diff --git a/include/grub/mips/linux.h b/include/grub/mips/linux.h
new file mode 100644
index 000000000..e69de29bb
diff --git a/include/grub/powerpc/linux.h b/include/grub/powerpc/linux.h
new file mode 100644
index 000000000..e69de29bb
diff --git a/include/grub/sparc64/linux.h b/include/grub/sparc64/linux.h
new file mode 100644
index 000000000..e69de29bb
diff --git a/grub-core/Makefile.am b/grub-core/Makefile.am
index f4ff62b76..9c69aa886 100644
--- a/grub-core/Makefile.am
+++ b/grub-core/Makefile.am
@@ -71,6 +71,7 @@ KERNEL_HEADER_FILES += $(top_srcdir)/include/grub/command.h
 KERNEL_HEADER_FILES += $(top_srcdir)/include/grub/device.h
 KERNEL_HEADER_FILES += $(top_srcdir)/include/grub/disk.h
 KERNEL_HEADER_FILES += $(top_srcdir)/include/grub/dl.h
+KERNEL_HEADER_FILES += $(top_srcdir)/include/grub/efi/sb.h
 KERNEL_HEADER_FILES += $(top_srcdir)/include/grub/env.h
 KERNEL_HEADER_FILES += $(top_srcdir)/include/grub/env_private.h
 KERNEL_HEADER_FILES += $(top_srcdir)/include/grub/err.h
