From 1a8916ee3ac29054322cdac687d36e1b5894d272 Mon Sep 17 00:00:00 2001 From: Nayna Jain Date: Tue, 5 Nov 2019 17:00:22 -0600 Subject: [PATCH] powerpc: Detect the secure boot mode of the system This patch defines a function to detect the secure boot state of a PowerNV system. The PPC_SECURE_BOOT config represents the base enablement of secure boot for powerpc. Signed-off-by: Nayna Jain Signed-off-by: Eric Richter [mpe: Fold in change from Nayna to add "ibm,secureboot" to ids] Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/46b003b9-3225-6bf7-9101-ed6580bb748c@linux.ibm.com --- arch/powerpc/Kconfig | 10 ++++++++++ arch/powerpc/include/asm/secure_boot.h | 23 ++++++++++++++++++++++ arch/powerpc/kernel/Makefile | 2 ++ arch/powerpc/kernel/secure_boot.c | 35 ++++++++++++++++++++++++++++++++++ 4 files changed, 70 insertions(+) create mode 100644 arch/powerpc/include/asm/secure_boot.h create mode 100644 arch/powerpc/kernel/secure_boot.c diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index 3e56c9c2f16e..56ea0019b616 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -934,6 +934,16 @@ config PPC_MEM_KEYS If unsure, say y. +config PPC_SECURE_BOOT + prompt "Enable secure boot support" + bool + depends on PPC_POWERNV + help + Systems with firmware secure boot enabled need to define security + policies to extend secure boot to the OS. This config allows a user + to enable OS secure boot on systems that have firmware support for + it. If in doubt say N. + endmenu config ISA_DMA_API diff --git a/arch/powerpc/include/asm/secure_boot.h b/arch/powerpc/include/asm/secure_boot.h new file mode 100644 index 000000000000..07d0fe0ca81f --- /dev/null +++ b/arch/powerpc/include/asm/secure_boot.h @@ -0,0 +1,23 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Secure boot definitions + * + * Copyright (C) 2019 IBM Corporation + * Author: Nayna Jain + */ +#ifndef _ASM_POWER_SECURE_BOOT_H +#define _ASM_POWER_SECURE_BOOT_H + +#ifdef CONFIG_PPC_SECURE_BOOT + +bool is_ppc_secureboot_enabled(void); + +#else + +static inline bool is_ppc_secureboot_enabled(void) +{ + return false; +} + +#endif +#endif diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile index a7ca8fe62368..e2a54fa240ac 100644 --- a/arch/powerpc/kernel/Makefile +++ b/arch/powerpc/kernel/Makefile @@ -161,6 +161,8 @@ ifneq ($(CONFIG_PPC_POWERNV)$(CONFIG_PPC_SVM),) obj-y += ucall.o endif +obj-$(CONFIG_PPC_SECURE_BOOT) += secure_boot.o + # Disable GCOV, KCOV & sanitizers in odd or sensitive code GCOV_PROFILE_prom_init.o := n KCOV_INSTRUMENT_prom_init.o := n diff --git a/arch/powerpc/kernel/secure_boot.c b/arch/powerpc/kernel/secure_boot.c new file mode 100644 index 000000000000..583c2c4edaf0 --- /dev/null +++ b/arch/powerpc/kernel/secure_boot.c @@ -0,0 +1,35 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2019 IBM Corporation + * Author: Nayna Jain + */ +#include +#include +#include + +static struct device_node *get_ppc_fw_sb_node(void) +{ + static const struct of_device_id ids[] = { + { .compatible = "ibm,secureboot", }, + { .compatible = "ibm,secureboot-v1", }, + { .compatible = "ibm,secureboot-v2", }, + {}, + }; + + return of_find_matching_node(NULL, ids); +} + +bool is_ppc_secureboot_enabled(void) +{ + struct device_node *node; + bool enabled = false; + + node = get_ppc_fw_sb_node(); + enabled = of_property_read_bool(node, "os-secureboot-enforcing"); + + of_node_put(node); + + pr_info("Secure boot mode %s\n", enabled ? "enabled" : "disabled"); + + return enabled; +} -- 2.11.0