On 10/30/19 10:31 PM, Mimi Zohar wrote:
> From: Nayna Jain <nayna@xxxxxxxxxxxxx>
>
> 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@xxxxxxxxxxxxx>
> ---
> 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
>
> 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");
Per skiboot changes, should instead look for "ibm,secureboot".
Updated set can be found here:
https://patchwork.ozlabs.org/project/skiboot/list/?series=140626
> + if (!of_device_is_available(node)) {
> + pr_err("Cannot find secure variable node in device tree; failing to secure state\n");
The default value for "enabled" is false, so it's actually failing insecure. Although, the print is
probably unnecessary.
> + goto out;
> + }
> +
> + /*
> + * secureboot is enabled if os-secure-enforcing property exists,
> + * else disabled.
> + */
> + enabled = of_property_read_bool(node, "os-secure-enforcing");
Property has been renamed to "os-secureboot-enforcing".
> +> +out:
> + of_node_put(node);
> +
> + pr_info("Secure boot mode %s\n", enabled ? "enabled" : "disabled");
> + return enabled;
> +}
>
