From 0914ade209c452cff6a29b1c0ae6fff3167fa1d0 Mon Sep 17 00:00:00 2001
From: Nayna Jain <nayna@linux.ibm.com>
Date: Tue, 9 Oct 2018 23:00:33 +0530
Subject: x86/ima: define arch_ima_get_secureboot

Distros are concerned about totally disabling the kexec_load syscall.
As a compromise, the kexec_load syscall will only be disabled when
CONFIG_KEXEC_VERIFY_SIG is configured and the system is booted with
secureboot enabled.

This patch defines the new arch specific function called
arch_ima_get_secureboot() to retrieve the secureboot state of the system.

Signed-off-by: Nayna Jain <nayna@linux.ibm.com>
Suggested-by: Seth Forshee <seth.forshee@canonical.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Peter Jones <pjones@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Dave Young <dyoung@redhat.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
---
 arch/x86/kernel/Makefile   |  2 ++
 arch/x86/kernel/ima_arch.c | 17 +++++++++++++++++
 2 files changed, 19 insertions(+)
 create mode 100644 arch/x86/kernel/ima_arch.c

(limited to 'arch')

diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
index 8824d01c0c35..f0910a1e1db7 100644
--- a/arch/x86/kernel/Makefile
+++ b/arch/x86/kernel/Makefile
@@ -150,3 +150,5 @@ ifeq ($(CONFIG_X86_64),y)
 	obj-$(CONFIG_MMCONF_FAM10H)	+= mmconf-fam10h_64.o
 	obj-y				+= vsmp_64.o
 endif
+
+obj-$(CONFIG_IMA)			+= ima_arch.o
diff --git a/arch/x86/kernel/ima_arch.c b/arch/x86/kernel/ima_arch.c
new file mode 100644
index 000000000000..bb5a88d2b271
--- /dev/null
+++ b/arch/x86/kernel/ima_arch.c
@@ -0,0 +1,17 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Copyright (C) 2018 IBM Corporation
+ */
+#include <linux/efi.h>
+#include <linux/ima.h>
+
+extern struct boot_params boot_params;
+
+bool arch_ima_get_secureboot(void)
+{
+	if (efi_enabled(EFI_BOOT) &&
+		(boot_params.secure_boot == efi_secureboot_mode_enabled))
+		return true;
+	else
+		return false;
+}
-- 
cgit v1.2.3