From 7a65d7b558974c89f19afaf0d78b54dc0327f56c Mon Sep 17 00:00:00 2001 From: Matthew Garrett Date: Wed, 15 Aug 2012 09:53:05 -0400 Subject: [PATCH] Don't permit insmod on secure boot References: fate#314485 Patch-Mainline: no Signed-off-by: Michael Chang --- grub-core/kern/corecmd.c | 9 +++++++++ grub-core/kern/efi/efi.c | 28 ++++++++++++++++++++++++++++ include/grub/efi/efi.h | 1 + 3 files changed, 38 insertions(+) Index: grub-2.00/grub-core/kern/corecmd.c =================================================================== --- grub-2.00.orig/grub-core/kern/corecmd.c +++ grub-2.00/grub-core/kern/corecmd.c @@ -28,6 +28,10 @@ #include #include +#ifdef GRUB_MACHINE_EFI +#include +#endif + /* set ENVVAR=VALUE */ static grub_err_t grub_core_cmd_set (struct grub_command *cmd __attribute__ ((unused)), @@ -75,6 +79,13 @@ grub_core_cmd_insmod (struct grub_comman { grub_dl_t mod; +#ifdef GRUB_MACHINE_EFI + if (grub_efi_secure_boot()) { + //grub_printf("%s\n", N_("Secure Boot forbids insmod")); + return 0; + } +#endif + if (argc == 0) return grub_error (GRUB_ERR_BAD_ARGUMENT, N_("one argument expected")); Index: grub-2.00/grub-core/kern/efi/efi.c =================================================================== --- grub-2.00.orig/grub-core/kern/efi/efi.c +++ grub-2.00/grub-core/kern/efi/efi.c @@ -259,6 +259,34 @@ 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-2.00/include/grub/efi/efi.h =================================================================== --- grub-2.00.orig/include/grub/efi/efi.h +++ grub-2.00/include/grub/efi/efi.h @@ -72,6 +72,7 @@ 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);