integrity: Make arch_ima_get_secureboot integrity-wide

EVM and other LSMs need the ability to query the secure boot status of
the system, without directly calling the IMA arch_ima_get_secureboot
function. Refactor the secure boot status check into a general function
named arch_get_secureboot.

Reported-and-suggested-by: Mimi Zohar <zohar@linux.ibm.com>
Suggested-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Coiby Xu <coxu@redhat.com>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>

1 files changed, 19 insertions, 0 deletions

diff --git a/include/linux/secure_boot.h b/include/linux/secure_boot.h
new file mode 100644
index 000000000000..3ded3f03655c
--- /dev/null
+++ b/include/linux/secure_boot.h
@@ -0,0 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2026 Red Hat, Inc. All Rights Reserved.
+ *
+ * Author: Coiby Xu <coxu@redhat.com>
+ */
+
+#ifndef _LINUX_SECURE_BOOT_H
+#define _LINUX_SECURE_BOOT_H
+
+#include <linux/types.h>
+
+/*
+ * Returns true if the platform secure boot is enabled.
+ * Returns false if disabled or not supported.
+ */
+bool arch_get_secureboot(void);
+
+#endif /* _LINUX_SECURE_BOOT_H */