Re: [PATCH v12 08/13] HP BIOSCFG driver - bioscfg-h

Jorge Lopez
2023-05-08T15:37:06Z

On Sat, May 6, 2023 at 2:15 AM Thomas Weißschuh <thomas@t-8ch.de> wrote:
>
> On 2023-05-05 17:00:38-0500, Jorge Lopez wrote:
> <snip>
>
> > ---
> > Based on the latest platform-drivers-x86.git/for-next
> > ---
> > drivers/platform/x86/hp/hp-bioscfg/bioscfg.h | 523 +++++++++++++++++++
> > 1 file changed, 523 insertions(+)
> > create mode 100644 drivers/platform/x86/hp/hp-bioscfg/bioscfg.h
> >
> > diff --git a/drivers/platform/x86/hp/hp-bioscfg/bioscfg.h b/drivers/platform/x86/hp/hp-bioscfg/bioscfg.h
> > new file mode 100644
> > index 000000000000..f27667d7ba9f
> > --- /dev/null
> > +++ b/drivers/platform/x86/hp/hp-bioscfg/bioscfg.h
> > @@ -0,0 +1,523 @@
> > +/* SPDX-License-Identifier: GPL-2.0
> > + *
> > + * Definitions for kernel modules using hp_bioscfg driver
> > + *
> > + * Copyright (c) 2022 HP Development Company, L.P.
> > + */
> > +
> > +#ifndef _HP_BIOSCFG_H_
> > +#define _HP_BIOSCFG_H_
> > +
> > +#include <linux/wmi.h>
> > +#include <linux/types.h>
> > +#include <linux/device.h>
> > +#include <linux/module.h>
> > +#include <linux/kernel.h>
> > +#include <linux/capability.h>
> > +#include <linux/nls.h>
> > +
> > +#define DRIVER_NAME "hp-bioscfg"
> > +
> > +#define MAX_BUFF 512
> > +#define MAX_KEY_MOD 256
>
> Seems to need _SIZE suffix.

Done!. I will update references in all files

>
> > +#define MAX_PASSWD_SIZE 64
> > +#define MAX_MESSAGE_SIZE 256
>
> Never used.

Done! MAX_MESSAGE_SIZE will be delete

>
> > +#define MAX_PREREQUISITES_SIZE 20
> > +#define MAX_REQ_ELEM_SIZE 128
> > +#define MAX_VALUES_SIZE 16
> > +#define MAX_ENCODINGS_SIZE 16
> > +#define MAX_ELEMENTS_SIZE 16
> > +
> > +#define SPM_STR_DESC "Secure Platform Management"
> > +#define SPM_STR "SPM"
> > +#define SURE_START_DESC "Sure Start"
> > +#define SURE_START_STR "Sure_Start"
> > +#define SETUP_PASSWD "Setup Password"
> > +#define POWER_ON_PASSWD "Power-On Password"
> > +
> > +#define LANG_CODE_STR "en_US.UTF-8"
> > +#define SCHEDULE_POWER_ON "Scheduled Power-On"
> > +
> > +#define COMMA_SEP ","
> > +#define SEMICOLON_SEP ";"
> > +
> > +/* Sure Admin Functions */
> > +
> > +#define UTF_PREFIX "<utf-16/>"
> > +#define BEAM_PREFIX "<BEAM/>"
> > +
> > +/* mechanism - Authentication attribute */
> > +
> > +#define MAX_MECHANISM_TYPES 3
>
> Never used.

Done!

>
> > +
> > +enum mechanism_values {
> > + PASSWORD = 0x00,
> > + NOT_PROVISION = 0x00,
>
> Never used.

Done!
>
> > + SIGNING_KEY = 0x01,
> > + ENDORSEMENT_KEY = 0x02,
> > +};
> > +

<snip>

> > +
> > +enum spm_features {
> > + HEP_ENABLED = 0x01,
> > + PLATFORM_RECOVERY = 0x02,
> > + ENHANCED_BIOS_AUTH_MODE = 0x04,
> > +};
> > +
> > +enum spm_states_values {
> > + NOT_PROVISIONED = 0x00,
> > + PROVISIONED = 0x01,
> > + PROVISIONING_IN_PROGRESS = 0x02,
> > +};
>
> Are these enums used?

Done!

>
> > +
> > +struct common_data {
> > + u8 display_name[MAX_BUFF];
> > + u8 path[MAX_BUFF];
> > + u32 is_readonly;
> > + u32 display_in_ui;
> > + u32 requires_physical_presence;
> > + u32 sequence;
> > + u32 prerequisites_size;
> > + u8 prerequisites[MAX_PREREQUISITES_SIZE][MAX_BUFF];
> > + u32 security_level;
> > + u8 display_name_language_code[MAX_BUFF];
> > +};
> > +
> > +struct string_data {
> > + struct common_data common;
> > + struct kobject *attr_name_kobj;
> > + u8 current_value[MAX_BUFF];
> > + u8 new_value[MAX_BUFF];
> > + u32 min_length;
> > + u32 max_length;
> > +};
> > +
> > +struct integer_data {
> > + struct common_data common;
> > + struct kobject *attr_name_kobj;
> > + u32 current_value;
> > + u32 new_value;
> > + u32 lower_bound;
> > + u32 upper_bound;
> > + u32 scalar_increment;
> > +};
> > +
> > +struct enumeration_data {
> > + struct common_data common;
> > + struct kobject *attr_name_kobj;
> > + u8 current_value[MAX_BUFF];
> > + u8 new_value[MAX_BUFF];
> > + u32 possible_values_size;
> > + u8 possible_values[MAX_VALUES_SIZE][MAX_BUFF];
> > +};
> > +
> > +struct ordered_list_data {
> > + struct common_data common;
> > + struct kobject *attr_name_kobj;
> > + u8 current_value[MAX_BUFF];
> > + u8 new_value[MAX_BUFF];
> > + u32 elements_size;
> > + u8 elements[MAX_ELEMENTS_SIZE][MAX_BUFF];
> > +};
> > +
> > +struct password_data {
> > + struct common_data common;
> > + struct kobject *attr_name_kobj;
> > + u8 current_password[MAX_PASSWD_SIZE];
> > + u8 new_password[MAX_PASSWD_SIZE];
> > + u32 min_password_length;
> > + u32 max_password_length;
> > + u32 encodings_size;
> > + u8 encodings[MAX_ENCODINGS_SIZE][MAX_BUFF];
> > + u32 is_enabled;
>
> If it is only being used as a boolean, bool is nicer.

Done!

>
> > +
> > + // 'bios-admin' 'power-on'
> > + u32 role;
>
> Are the comments about the possible values or the context in which this
> field will be used?
> This should be clear.

'role' is described in the documentation

role:
The type of authentication used.
This attribute is mandatory.

Known types:
bios-admin:
Representing BIOS administrator password
power-on:
Representing a password required to use
the system

I will add similar comments to the code.

> > +
> > + //'password'
> > + u32 mechanism;
> > +};
> > +
> > +struct secure_platform_data {
> > + struct kobject *attr_name_kobj;
> > + u8 attribute_name[MAX_BUFF];
> > + u8 *endorsement_key;
> > + u8 *signing_key;
> > + u8 *auth_token;
> > + u32 is_enabled;
>
> Also bool.

Done!
>
> > + u32 mechanism;
> > +};
> > +
> > +struct bioscfg_priv {
> > + struct wmi_device *bios_attr_wdev;
> > + struct kset *authentication_dir_kset;
> > + struct kset *main_dir_kset;
> > + struct device *class_dev;
> > + struct string_data *string_data;
> > + u32 string_instances_count;
> > + struct integer_data *integer_data;
> > + u32 integer_instances_count;
> > + struct enumeration_data *enumeration_data;
> > + u32 enumeration_instances_count;
> > + struct ordered_list_data *ordered_list_data;
> > + u32 ordered_list_instances_count;
> > + struct password_data *password_data;
> > + u32 password_instances_count;
> > +
> > + struct kobject *sure_start_attr_kobj;
> > + struct secure_platform_data spm_data;
> > +
> > + bool pending_reboot;
> > + struct mutex mutex;
> > +};
> > +
> > +/* global structure used by multiple WMI interfaces */
> > +extern struct bioscfg_priv bioscfg_drv;
> > +
> > +enum hp_wmi_data_type {
> > + HPWMI_STRING_TYPE = 0x00,
> > + HPWMI_INTEGER_TYPE = 0x01,
> > + HPWMI_ENUMERATION_TYPE = 0x02,
> > + HPWMI_ORDERED_LIST_TYPE = 0x03,
> > + HPWMI_PASSWORD_TYPE = 0x04,
> > + HPWMI_SECURE_PLATFORM_TYPE = 0x05,
> > + HPWMI_SURE_START_TYPE = 0x06,
> > +};
>
> There is no need to explicitly specify enum values when they don't
> matter.
> This makes it clear if an enum represents values for an external ABI or
> if it is just for internal use.
>

I added them for my clarification, in the event enums added at a later
time do not have a sequential value.
This is not the case here so I will remove the value.
Done!

<snip>
> > +#define ATTRIBUTE_S_COMMON_PROPERTY_SHOW(name, type) \
> > + static ssize_t name##_show(struct kobject *kobj, struct kobj_attribute *attr, \
> > + char *buf) \
> > + { \
> > + int i = get_##type##_instance_id(kobj); \
> > + if (i >= 0) \
> > + return sysfs_emit(buf, "%s\n", bioscfg_drv.type##_data[i].common.name); \
> > + return -EIO; \
> > + }
> > +
> > +/*
> > + * Prototypes
> > + */
> > +union acpi_object *get_wmiobj_pointer(int instance_id, const char *guid_string);
>
> Weren't all non-static functions supposed to gain a common prefix?

I misunderstood an earlier comment and made only all functions with
current prefixes to have a common one.
I will add a prefix to all common functions.

>
> > +int get_instance_count(const char *guid_string);
> > +void update_attribute_permissions(u32 isreadonly, struct kobj_attribute *current_val);
>
> "bool readonly" should be enough.

Done!

>
> > +void friendly_user_name_update(char *path, const char *attr_name,
> > + char *attr_display, int attr_size);
> > +int hp_wmi_error_and_message(int error_code);
> > +
> > +/* String attributes */
> > +int populate_string_buffer_data(u8 *buffer_ptr, u32 *buffer_size,
> > + int instance_id,
> > + struct kobject *attr_name_kobj);
> > +
> > +int populate_string_elements_from_buffer(u8 *buffer_ptr, u32 *buffer_size,
> > + int instance_id);
> > +int alloc_string_data(void);
> > +void exit_string_attributes(void);
> > +int populate_string_package_data(union acpi_object *str_obj,
> > + int instance_id,
> > + struct kobject *attr_name_kobj);
> > +int populate_string_elements_from_package(union acpi_object *str_obj,
> > + int str_obj_count,
> > + int instance_id);
> > +
> > +/* Integer attributes */
> > +int populate_integer_buffer_data(u8 *buffer_ptr, u32 *buffer_size,
> > + int instance_id,
> > + struct kobject *attr_name_kobj);
> > +int populate_integer_elements_from_buffer(u8 *buffer_ptr, u32 *buffer_size,
> > + int instance_id);
> > +int alloc_integer_data(void);
> > +void exit_integer_attributes(void);
> > +int populate_integer_package_data(union acpi_object *integer_obj,
> > + int instance_id,
> > + struct kobject *attr_name_kobj);
> > +int populate_integer_elements_from_package(union acpi_object *integer_obj,
> > + int integer_obj_count,
> > + int instance_id);
> > +
> > +/* Enumeration attributes */
> > +int populate_enumeration_buffer_data(u8 *buffer_ptr, u32 *buffer_size,
> > + int instance_id,
> > + struct kobject *attr_name_kobj);
> > +int populate_enumeration_elements_from_buffer(u8 *buffer_ptr, u32 *buffer_size,
> > + int instance_id);
> > +int alloc_enumeration_data(void);
> > +void exit_enumeration_attributes(void);
> > +int populate_enumeration_package_data(union acpi_object *enum_obj,
> > + int instance_id,
> > + struct kobject *attr_name_kobj);
> > +int populate_enumeration_elements_from_package(union acpi_object *enum_obj,
> > + int enum_obj_count,
> > + int instance_id);
> > +
> > +/* Ordered list */
> > +int populate_ordered_list_buffer_data(u8 *buffer_ptr,
> > + u32 *buffer_size,
> > + int instance_id,
> > + struct kobject *attr_name_kobj);
> > +int populate_ordered_list_elements_from_buffer(u8 *buffer_ptr,
> > + u32 *buffer_size,
> > + int instance_id);
> > +int alloc_ordered_list_data(void);
> > +void exit_ordered_list_attributes(void);
> > +int populate_ordered_list_package_data(union acpi_object *order_obj,
> > + int instance_id,
> > + struct kobject *attr_name_kobj);
> > +int populate_ordered_list_elements_from_package(union acpi_object *order_obj,
> > + int order_obj_count,
> > + int instance_id);
> > +
> > +/* Password authentication attributes */
> > +int populate_password_buffer_data(u8 *buffer_ptr, u32 *buffer_size,
> > + int instance_id,
> > + struct kobject *attr_name_kobj);
> > +int populate_password_elements_from_buffer(u8 *buffer_ptr, u32 *buffer_size,
> > + int instance_id);
> > +int populate_password_package_data(union acpi_object *password_obj,
> > + int instance_id,
> > + struct kobject *attr_name_kobj);
> > +int populate_password_elements_from_package(union acpi_object *password_obj,
> > + int password_obj_count,
> > + int instance_id);
> > +int alloc_password_data(void);
> > +int alloc_secure_platform_data(void);
> > +void exit_password_attributes(void);
> > +void exit_secure_platform_attributes(void);
> > +int populate_secure_platform_data(struct kobject *attr_name_kobj);
> > +int check_spm_is_enabled(void);
> > +int hp_wmi_set_bios_setting(u16 *input_buffer, u32 input_size);
> > +int hp_wmi_perform_query(int query, enum hp_wmi_command command,
> > + void *buffer, u32 insize, u32 outsize);
> > +int validate_password_input(int instance_id, const char *buf);
> > +
> > +/* Sure Start attributes */
> > +void exit_sure_start_attributes(void);
> > +int populate_sure_start_data(struct kobject *attr_name_kobj);
> > +
> > +int set_bios_defaults(u8 deftype);
>
> This seems not to actually exist.
>
> > +int get_password_instance_for_type(const char *name);
> > +int clear_all_credentials(void);
> > +int clear_passwords(const int instance);
> > +void exit_hp_attr_set_interface(void);
> > +int init_hp_attr_set_interface(void);
> > +size_t hp_calculate_string_buffer(const char *str);
> > +size_t calculate_security_buffer(const char *authentication);
> > +int populate_security_buffer(u16 *buffer, const char *authentication);
> > +int set_new_password(const char *password_type, const char *new_password);
> > +int init_hp_attr_pass_interface(void);
> > +void exit_hp_attr_pass_interface(void);
> > +void *hp_ascii_to_utf16_unicode(u16 *p, const u8 *str);
> > +int get_integer_from_buffer(u8 **buffer, u32 *buffer_size, u32 *integer);
> > +int get_string_from_buffer(u8 **buffer, u32 *buffer_size, char *dst, u32 dst_size);
> > +int convert_hexstr_to_str(const char *input, u32 input_len, char **str, int *len);
> > +int encode_outsize_for_pvsz(int outsize);
> > +int hp_set_attribute(const char *a_name, const char *a_value);
> > +int enforce_single_line_input(char *buf, size_t count);
> > +void set_reboot_and_signal_event(void);
> > +
> > +#endif
> > --
> > 2.34.1
> >