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-rw-r--r--arch/powerpc/Kconfig1
-rw-r--r--arch/powerpc/kernel/Makefile2
-rw-r--r--arch/powerpc/kernel/ima_arch.c43
3 files changed, 45 insertions, 1 deletions
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 56ea0019b616..c795039bdc73 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -938,6 +938,7 @@ config PPC_SECURE_BOOT
prompt "Enable secure boot support"
bool
depends on PPC_POWERNV
+ depends on IMA_ARCH_POLICY
help
Systems with firmware secure boot enabled need to define security
policies to extend secure boot to the OS. This config allows a user
diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile
index e2a54fa240ac..e8eb2955b7d5 100644
--- a/arch/powerpc/kernel/Makefile
+++ b/arch/powerpc/kernel/Makefile
@@ -161,7 +161,7 @@ ifneq ($(CONFIG_PPC_POWERNV)$(CONFIG_PPC_SVM),)
obj-y += ucall.o
endif
-obj-$(CONFIG_PPC_SECURE_BOOT) += secure_boot.o
+obj-$(CONFIG_PPC_SECURE_BOOT) += secure_boot.o ima_arch.o
# Disable GCOV, KCOV & sanitizers in odd or sensitive code
GCOV_PROFILE_prom_init.o := n
diff --git a/arch/powerpc/kernel/ima_arch.c b/arch/powerpc/kernel/ima_arch.c
new file mode 100644
index 000000000000..d88913dc0da7
--- /dev/null
+++ b/arch/powerpc/kernel/ima_arch.c
@@ -0,0 +1,43 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2019 IBM Corporation
+ * Author: Nayna Jain
+ */
+
+#include <linux/ima.h>
+#include <asm/secure_boot.h>
+
+bool arch_ima_get_secureboot(void)
+{
+ return is_ppc_secureboot_enabled();
+}
+
+/*
+ * The "secure_rules" are enabled only on "secureboot" enabled systems.
+ * These rules verify the file signatures against known good values.
+ * The "appraise_type=imasig|modsig" option allows the known good signature
+ * to be stored as an xattr or as an appended signature.
+ *
+ * To avoid duplicate signature verification as much as possible, the IMA
+ * policy rule for module appraisal is added only if CONFIG_MODULE_SIG_FORCE
+ * is not enabled.
+ */
+static const char *const secure_rules[] = {
+ "appraise func=KEXEC_KERNEL_CHECK appraise_type=imasig|modsig",
+#ifndef CONFIG_MODULE_SIG_FORCE
+ "appraise func=MODULE_CHECK appraise_type=imasig|modsig",
+#endif
+ NULL
+};
+
+/*
+ * Returns the relevant IMA arch-specific policies based on the system secure
+ * boot state.
+ */
+const char *const *arch_get_ima_policy(void)
+{
+ if (is_ppc_secureboot_enabled())
+ return secure_rules;
+
+ return NULL;
+}