From 29c89e27805f7a6a22bce11ed9bb430e19c972a9 Mon Sep 17 00:00:00 2001 From: Colin Watson 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 --- 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 +#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);