The /sys/firmware/secvar/config directory represents Power LPAR Platform KeyStore (PLPKS) configuration properties such as max_object_size, signed_ update_algorithms, supported_policies, total_size, used_space, and version. These attributes describe the PLPKS, and not the secure boot variables (secvars).
Create /sys/firmware/plpks directory and move the PLPKS config inside this directory. For backwards compatibility, create a soft link from the secvar sysfs directory to this config and emit a warning stating that the older sysfs path has been deprecated. Separate out the plpks specific documentation from secvar. Signed-off-by: Srish Srinivasan <[email protected]> --- .../ABI/testing/sysfs-firmware-plpks | 50 ++++++++++ Documentation/ABI/testing/sysfs-secvar | 65 ------------- arch/powerpc/include/asm/plpks.h | 4 + arch/powerpc/include/asm/secvar.h | 1 - arch/powerpc/kernel/secvar-sysfs.c | 21 ++--- arch/powerpc/platforms/pseries/Makefile | 2 +- arch/powerpc/platforms/pseries/plpks-secvar.c | 29 ------ arch/powerpc/platforms/pseries/plpks-sysfs.c | 94 +++++++++++++++++++ 8 files changed, 155 insertions(+), 111 deletions(-) create mode 100644 Documentation/ABI/testing/sysfs-firmware-plpks create mode 100644 arch/powerpc/platforms/pseries/plpks-sysfs.c diff --git a/Documentation/ABI/testing/sysfs-firmware-plpks b/Documentation/ABI/testing/sysfs-firmware-plpks new file mode 100644 index 000000000000..af0353f34115 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-firmware-plpks @@ -0,0 +1,50 @@ +What: /sys/firmware/plpks/config +Date: February 2023 +Contact: Nayna Jain <[email protected]> +Description: This optional directory contains read-only config attributes as + defined by the PLPKS implementation. All data is in ASCII + format. + +What: /sys/firmware/plpks/config/version +Date: February 2023 +Contact: Nayna Jain <[email protected]> +Description: Config version as reported by the hypervisor in ASCII decimal + format. + +What: /sys/firmware/plpks/config/max_object_size +Date: February 2023 +Contact: Nayna Jain <[email protected]> +Description: Maximum allowed size of objects in the keystore in bytes, + represented in ASCII decimal format. + + This is not necessarily the same as the max size that can be + written to an update file as writes can contain more than + object data, you should use the size of the update file for + that purpose. + +What: /sys/firmware/plpks/config/total_size +Date: February 2023 +Contact: Nayna Jain <[email protected]> +Description: Total size of the PLPKS in bytes, represented in ASCII decimal + format. + +What: /sys/firmware/plpks/config/used_space +Date: February 2023 +Contact: Nayna Jain <[email protected]> +Description: Current space consumed by the key store, in bytes, represented + in ASCII decimal format. + +What: /sys/firmware/plpks/config/supported_policies +Date: February 2023 +Contact: Nayna Jain <[email protected]> +Description: Bitmask of supported policy flags by the hypervisor, represented + as an 8 byte hexadecimal ASCII string. Consult the hypervisor + documentation for what these flags are. + +What: /sys/firmware/plpks/config/signed_update_algorithms +Date: February 2023 +Contact: Nayna Jain <[email protected]> +Description: Bitmask of flags indicating which algorithms the hypervisor + supports for signed update of objects, represented as a 16 byte + hexadecimal ASCII string. Consult the hypervisor documentation + for what these flags mean. diff --git a/Documentation/ABI/testing/sysfs-secvar b/Documentation/ABI/testing/sysfs-secvar index 1016967a730f..c52a5fd15709 100644 --- a/Documentation/ABI/testing/sysfs-secvar +++ b/Documentation/ABI/testing/sysfs-secvar @@ -63,68 +63,3 @@ Contact: Nayna Jain <[email protected]> Description: A write-only file that is used to submit the new value for the variable. The size of the file represents the maximum size of the variable data that can be written. - -What: /sys/firmware/secvar/config -Date: February 2023 -Contact: Nayna Jain <[email protected]> -Description: This optional directory contains read-only config attributes as - defined by the secure variable implementation. All data is in - ASCII format. The directory is only created if the backing - implementation provides variables to populate it, which at - present is only PLPKS on the pseries platform. - -What: /sys/firmware/secvar/config/version -Date: February 2023 -Contact: Nayna Jain <[email protected]> -Description: Config version as reported by the hypervisor in ASCII decimal - format. - - Currently only provided by PLPKS on the pseries platform. - -What: /sys/firmware/secvar/config/max_object_size -Date: February 2023 -Contact: Nayna Jain <[email protected]> -Description: Maximum allowed size of objects in the keystore in bytes, - represented in ASCII decimal format. - - This is not necessarily the same as the max size that can be - written to an update file as writes can contain more than - object data, you should use the size of the update file for - that purpose. - - Currently only provided by PLPKS on the pseries platform. - -What: /sys/firmware/secvar/config/total_size -Date: February 2023 -Contact: Nayna Jain <[email protected]> -Description: Total size of the PLPKS in bytes, represented in ASCII decimal - format. - - Currently only provided by PLPKS on the pseries platform. - -What: /sys/firmware/secvar/config/used_space -Date: February 2023 -Contact: Nayna Jain <[email protected]> -Description: Current space consumed by the key store, in bytes, represented - in ASCII decimal format. - - Currently only provided by PLPKS on the pseries platform. - -What: /sys/firmware/secvar/config/supported_policies -Date: February 2023 -Contact: Nayna Jain <[email protected]> -Description: Bitmask of supported policy flags by the hypervisor, - represented as an 8 byte hexadecimal ASCII string. Consult the - hypervisor documentation for what these flags are. - - Currently only provided by PLPKS on the pseries platform. - -What: /sys/firmware/secvar/config/signed_update_algorithms -Date: February 2023 -Contact: Nayna Jain <[email protected]> -Description: Bitmask of flags indicating which algorithms the hypervisor - supports for signed update of objects, represented as a 16 byte - hexadecimal ASCII string. Consult the hypervisor documentation - for what these flags mean. - - Currently only provided by PLPKS on the pseries platform. diff --git a/arch/powerpc/include/asm/plpks.h b/arch/powerpc/include/asm/plpks.h index f303922bf622..53e5839b0cbe 100644 --- a/arch/powerpc/include/asm/plpks.h +++ b/arch/powerpc/include/asm/plpks.h @@ -13,6 +13,7 @@ #include <linux/types.h> #include <linux/list.h> +#include <linux/kobject.h> // Object policy flags from supported_policies #define PLPKS_OSSECBOOTAUDIT PPC_BIT32(1) // OS secure boot must be audit/enforce @@ -107,11 +108,14 @@ u16 plpks_get_passwordlen(void); void plpks_early_init_devtree(void); int plpks_populate_fdt(void *fdt); + +int plpks_config_create_softlink(struct kobject *from); #else // CONFIG_PSERIES_PLPKS static inline bool plpks_is_available(void) { return false; } static inline u16 plpks_get_passwordlen(void) { BUILD_BUG(); } static inline void plpks_early_init_devtree(void) { } static inline int plpks_populate_fdt(void *fdt) { BUILD_BUG(); } +static int plpks_config_create_softlink(struct kobject *from) { return 0; } #endif // CONFIG_PSERIES_PLPKS #endif // _ASM_POWERPC_PLPKS_H diff --git a/arch/powerpc/include/asm/secvar.h b/arch/powerpc/include/asm/secvar.h index 4828e0ab7e3c..fd5006307f2a 100644 --- a/arch/powerpc/include/asm/secvar.h +++ b/arch/powerpc/include/asm/secvar.h @@ -20,7 +20,6 @@ struct secvar_operations { int (*set)(const char *key, u64 key_len, u8 *data, u64 data_size); ssize_t (*format)(char *buf, size_t bufsize); int (*max_size)(u64 *max_size); - const struct attribute **config_attrs; // NULL-terminated array of fixed variable names // Only used if get_next() isn't provided diff --git a/arch/powerpc/kernel/secvar-sysfs.c b/arch/powerpc/kernel/secvar-sysfs.c index ec900bce0257..4111b21962eb 100644 --- a/arch/powerpc/kernel/secvar-sysfs.c +++ b/arch/powerpc/kernel/secvar-sysfs.c @@ -12,6 +12,7 @@ #include <linux/string.h> #include <linux/of.h> #include <asm/secvar.h> +#include <asm/plpks.h> #define NAME_MAX_SIZE 1024 @@ -145,19 +146,6 @@ static __init int update_kobj_size(void) return 0; } -static __init int secvar_sysfs_config(struct kobject *kobj) -{ - struct attribute_group config_group = { - .name = "config", - .attrs = (struct attribute **)secvar_ops->config_attrs, - }; - - if (secvar_ops->config_attrs) - return sysfs_create_group(kobj, &config_group); - - return 0; -} - static __init int add_var(const char *name) { struct kobject *kobj; @@ -260,12 +248,15 @@ static __init int secvar_sysfs_init(void) goto err; } - rc = secvar_sysfs_config(secvar_kobj); + rc = plpks_config_create_softlink(secvar_kobj); if (rc) { - pr_err("Failed to create config directory\n"); + pr_err("Failed to create softlink to PLPKS config directory"); goto err; } + pr_info("/sys/firmware/secvar/config is now deprecated.\n"); + pr_info("Will be removed in future versions.\n"); + if (secvar_ops->get_next) rc = secvar_sysfs_load(); else diff --git a/arch/powerpc/platforms/pseries/Makefile b/arch/powerpc/platforms/pseries/Makefile index 931ebaa474c8..3ced289a675b 100644 --- a/arch/powerpc/platforms/pseries/Makefile +++ b/arch/powerpc/platforms/pseries/Makefile @@ -30,7 +30,7 @@ obj-$(CONFIG_PAPR_SCM) += papr_scm.o obj-$(CONFIG_PPC_SPLPAR) += vphn.o obj-$(CONFIG_PPC_SVM) += svm.o obj-$(CONFIG_FA_DUMP) += rtas-fadump.o -obj-$(CONFIG_PSERIES_PLPKS) += plpks.o +obj-$(CONFIG_PSERIES_PLPKS) += plpks.o plpks-sysfs.o obj-$(CONFIG_PPC_SECURE_BOOT) += plpks-secvar.o obj-$(CONFIG_PSERIES_PLPKS_SED) += plpks_sed_ops.o obj-$(CONFIG_SUSPEND) += suspend.o diff --git a/arch/powerpc/platforms/pseries/plpks-secvar.c b/arch/powerpc/platforms/pseries/plpks-secvar.c index f9e9cc40c9d0..a50ff6943d80 100644 --- a/arch/powerpc/platforms/pseries/plpks-secvar.c +++ b/arch/powerpc/platforms/pseries/plpks-secvar.c @@ -20,33 +20,6 @@ #include <asm/secvar.h> #include <asm/plpks.h> -// Config attributes for sysfs -#define PLPKS_CONFIG_ATTR(name, fmt, func) \ - static ssize_t name##_show(struct kobject *kobj, \ - struct kobj_attribute *attr, \ - char *buf) \ - { \ - return sysfs_emit(buf, fmt, func()); \ - } \ - static struct kobj_attribute attr_##name = __ATTR_RO(name) - -PLPKS_CONFIG_ATTR(version, "%u\n", plpks_get_version); -PLPKS_CONFIG_ATTR(max_object_size, "%u\n", plpks_get_maxobjectsize); -PLPKS_CONFIG_ATTR(total_size, "%u\n", plpks_get_totalsize); -PLPKS_CONFIG_ATTR(used_space, "%u\n", plpks_get_usedspace); -PLPKS_CONFIG_ATTR(supported_policies, "%08x\n", plpks_get_supportedpolicies); -PLPKS_CONFIG_ATTR(signed_update_algorithms, "%016llx\n", plpks_get_signedupdatealgorithms); - -static const struct attribute *config_attrs[] = { - &attr_version.attr, - &attr_max_object_size.attr, - &attr_total_size.attr, - &attr_used_space.attr, - &attr_supported_policies.attr, - &attr_signed_update_algorithms.attr, - NULL, -}; - static u32 get_policy(const char *name) { if ((strcmp(name, "db") == 0) || @@ -225,7 +198,6 @@ static const struct secvar_operations plpks_secvar_ops_static = { .set = plpks_set_variable, .format = plpks_secvar_format, .max_size = plpks_max_size, - .config_attrs = config_attrs, .var_names = plpks_var_names_static, }; @@ -234,7 +206,6 @@ static const struct secvar_operations plpks_secvar_ops_dynamic = { .set = plpks_set_variable, .format = plpks_secvar_format, .max_size = plpks_max_size, - .config_attrs = config_attrs, .var_names = plpks_var_names_dynamic, }; diff --git a/arch/powerpc/platforms/pseries/plpks-sysfs.c b/arch/powerpc/platforms/pseries/plpks-sysfs.c new file mode 100644 index 000000000000..01d526185783 --- /dev/null +++ b/arch/powerpc/platforms/pseries/plpks-sysfs.c @@ -0,0 +1,94 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2025 IBM Corporation, Srish Srinivasan <[email protected]> + * + * This code exposes PLPKS config to user via sysfs + */ + +#define pr_fmt(fmt) "plpks-sysfs: "fmt + +#include <linux/init.h> +#include <linux/printk.h> +#include <linux/types.h> +#include <asm/machdep.h> +#include <asm/plpks.h> + +/* config attributes for sysfs */ +#define PLPKS_CONFIG_ATTR(name, fmt, func) \ + static ssize_t name##_show(struct kobject *kobj, \ + struct kobj_attribute *attr, \ + char *buf) \ + { \ + return sysfs_emit(buf, fmt, func()); \ + } \ + static struct kobj_attribute attr_##name = __ATTR_RO(name) + +PLPKS_CONFIG_ATTR(version, "%u\n", plpks_get_version); +PLPKS_CONFIG_ATTR(max_object_size, "%u\n", plpks_get_maxobjectsize); +PLPKS_CONFIG_ATTR(total_size, "%u\n", plpks_get_totalsize); +PLPKS_CONFIG_ATTR(used_space, "%u\n", plpks_get_usedspace); +PLPKS_CONFIG_ATTR(supported_policies, "%08x\n", plpks_get_supportedpolicies); +PLPKS_CONFIG_ATTR(signed_update_algorithms, "%016llx\n", + plpks_get_signedupdatealgorithms); + +static const struct attribute *config_attrs[] = { + &attr_version.attr, + &attr_max_object_size.attr, + &attr_total_size.attr, + &attr_used_space.attr, + &attr_supported_policies.attr, + &attr_signed_update_algorithms.attr, + NULL, +}; + +static struct kobject *plpks_kobj, *plpks_config_kobj; + +int plpks_config_create_softlink(struct kobject *from) +{ + if (!plpks_config_kobj) + return -EINVAL; + return sysfs_create_link(from, plpks_config_kobj, "config"); +} + +static __init int plpks_sysfs_config(struct kobject *kobj) +{ + struct attribute_group config_group = { + .name = NULL, + .attrs = (struct attribute **)config_attrs, + }; + + return sysfs_create_group(kobj, &config_group); +} + +static __init int plpks_sysfs_init(void) +{ + int rc; + + if (!plpks_is_available()) + return -ENODEV; + + plpks_kobj = kobject_create_and_add("plpks", firmware_kobj); + if (!plpks_kobj) { + pr_err("Failed to create plpks kobj\n"); + return -ENOMEM; + } + + plpks_config_kobj = kobject_create_and_add("config", plpks_kobj); + if (!plpks_config_kobj) { + pr_err("Failed to create plpks config kobj\n"); + kobject_put(plpks_kobj); + return -ENOMEM; + } + + rc = plpks_sysfs_config(plpks_config_kobj); + if (rc) { + pr_err("Failed to create attribute group for plpks config\n"); + kobject_put(plpks_config_kobj); + kobject_put(plpks_kobj); + return rc; + } + + return 0; +} + +machine_subsys_initcall(pseries, plpks_sysfs_init); -- 2.47.3
