| Message ID | 20191024034717.70552-2-nayna@linux.ibm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | powerpc: Enabling IMA arch specific secure boot policies | expand |
On 10/23/2019 8:47 PM, Nayna Jain wrote: > This patch defines a function to detect the secure boot state of a > PowerNV system. > +bool is_ppc_secureboot_enabled(void) > +{ > + struct device_node *node; > + bool enabled = false; > + > + node = of_find_compatible_node(NULL, NULL, "ibm,secvar-v1"); > + if (!of_device_is_available(node)) { > + pr_err("Cannot find secure variable node in device tree; failing to secure state\n"); > + goto out; Related to "goto out;" above: Would of_find_compatible_node return NULL if the given node is not found? If of_device_is_available returns false (say, because node is NULL or it does not find the specified node) would it be correct to call of_node_put? > + > +out: > + of_node_put(node); -lakshmi
On 10/24/19 12:26 PM, Lakshmi Ramasubramanian wrote: > On 10/23/2019 8:47 PM, Nayna Jain wrote: >> This patch defines a function to detect the secure boot state of a >> PowerNV system. > >> +bool is_ppc_secureboot_enabled(void) >> +{ >> + struct device_node *node; >> + bool enabled = false; >> + >> + node = of_find_compatible_node(NULL, NULL, "ibm,secvar-v1"); >> + if (!of_device_is_available(node)) { >> + pr_err("Cannot find secure variable node in device tree; >> failing to secure state\n"); >> + goto out; > > Related to "goto out;" above: > > Would of_find_compatible_node return NULL if the given node is not found? > > If of_device_is_available returns false (say, because node is NULL or > it does not find the specified node) would it be correct to call > of_node_put? of_node_put() handles NULL. Thanks & Regards, - Nayna
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..63dc82c50862 --- /dev/null +++ b/arch/powerpc/kernel/secure_boot.c @@ -0,0 +1,32 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2019 IBM Corporation + * Author: Nayna Jain + */ +#include <linux/types.h> +#include <linux/of.h> +#include <asm/secure_boot.h> + +bool is_ppc_secureboot_enabled(void) +{ + struct device_node *node; + bool enabled = false; + + node = of_find_compatible_node(NULL, NULL, "ibm,secvar-v1"); + if (!of_device_is_available(node)) { + pr_err("Cannot find secure variable node in device tree; failing to secure state\n"); + goto out; + } + + /* + * secureboot is enabled if os-secure-enforcing property exists, + * else disabled. + */ + enabled = of_property_read_bool(node, "os-secure-enforcing"); + +out: + of_node_put(node); + + pr_info("Secure boot mode %s\n", enabled ? "enabled" : "disabled"); + return enabled; +}
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 <nayna@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 | 32 ++++++++++++++++++++++++++ 4 files changed, 67 insertions(+) create mode 100644 arch/powerpc/include/asm/secure_boot.h create mode 100644 arch/powerpc/kernel/secure_boot.c