diff options
Diffstat (limited to 'drivers/platform/x86/hp/hp-bioscfg/passwdobj-attributes.c')
| -rw-r--r-- | drivers/platform/x86/hp/hp-bioscfg/passwdobj-attributes.c | 556 |
1 files changed, 556 insertions, 0 deletions
diff --git a/drivers/platform/x86/hp/hp-bioscfg/passwdobj-attributes.c b/drivers/platform/x86/hp/hp-bioscfg/passwdobj-attributes.c new file mode 100644 index 000000000000..03d0188804ba --- /dev/null +++ b/drivers/platform/x86/hp/hp-bioscfg/passwdobj-attributes.c @@ -0,0 +1,556 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Functions corresponding to password object type attributes under + * BIOS PASSWORD for use with hp-bioscfg driver. + * + * Copyright (c) 2022 HP Development Company, L.P. + */ + +#include "bioscfg.h" +#include <asm-generic/posix_types.h> + +GET_INSTANCE_ID(password); +/* + * Clear all passwords copied to memory for a particular + * authentication instance + */ +static int clear_passwords(const int instance) +{ + struct password_data *password_data = &bioscfg_drv.password_data[instance]; + + if (!password_data->is_enabled) + return 0; + + memset(password_data->current_password, + 0, sizeof(password_data->current_password)); + memset(password_data->new_password, + 0, sizeof(password_data->new_password)); + + return 0; +} + +/* + * Clear all credentials copied to memory for both Power-ON and Setup + * BIOS instances + */ +int hp_clear_all_credentials(void) +{ + int count = bioscfg_drv.password_instances_count; + int instance; + + /* clear all passwords */ + for (instance = 0; instance < count; instance++) + clear_passwords(instance); + + /* clear auth_token */ + kfree(bioscfg_drv.spm_data.auth_token); + bioscfg_drv.spm_data.auth_token = NULL; + + return 0; +} + +int hp_get_password_instance_for_type(const char *name) +{ + int count = bioscfg_drv.password_instances_count; + int instance; + + for (instance = 0; instance < count; instance++) + if (!strcmp(bioscfg_drv.password_data[instance].common.display_name, name)) + return instance; + + return -EINVAL; +} + +static int validate_password_input(int instance_id, const char *buf) +{ + int length; + struct password_data *password_data = &bioscfg_drv.password_data[instance_id]; + + length = strlen(buf); + if (buf[length - 1] == '\n') + length--; + + if (length > MAX_PASSWD_SIZE) + return INVALID_BIOS_AUTH; + + if (password_data->min_password_length > length || + password_data->max_password_length < length) + return INVALID_BIOS_AUTH; + return SUCCESS; +} + +ATTRIBUTE_N_PROPERTY_SHOW(is_enabled, password); +static struct kobj_attribute password_is_password_set = __ATTR_RO(is_enabled); + +static int store_password_instance(struct kobject *kobj, const char *buf, + size_t count, bool is_current) +{ + char *buf_cp; + int id, ret = 0; + + buf_cp = kstrdup(buf, GFP_KERNEL); + if (!buf_cp) + return -ENOMEM; + + ret = hp_enforce_single_line_input(buf_cp, count); + if (!ret) { + id = get_password_instance_id(kobj); + + if (id >= 0) + ret = validate_password_input(id, buf_cp); + } + + if (!ret) { + if (is_current) + strscpy(bioscfg_drv.password_data[id].current_password, + buf_cp, + sizeof(bioscfg_drv.password_data[id].current_password)); + else + strscpy(bioscfg_drv.password_data[id].new_password, + buf_cp, + sizeof(bioscfg_drv.password_data[id].new_password)); + } + + kfree(buf_cp); + return ret < 0 ? ret : count; +} + +static ssize_t current_password_store(struct kobject *kobj, + struct kobj_attribute *attr, + const char *buf, size_t count) +{ + return store_password_instance(kobj, buf, count, true); +} + +static struct kobj_attribute password_current_password = __ATTR_WO(current_password); + +static ssize_t new_password_store(struct kobject *kobj, + struct kobj_attribute *attr, + const char *buf, size_t count) +{ + return store_password_instance(kobj, buf, count, true); +} + +static struct kobj_attribute password_new_password = __ATTR_WO(new_password); + +ATTRIBUTE_N_PROPERTY_SHOW(min_password_length, password); +static struct kobj_attribute password_min_password_length = __ATTR_RO(min_password_length); + +ATTRIBUTE_N_PROPERTY_SHOW(max_password_length, password); +static struct kobj_attribute password_max_password_length = __ATTR_RO(max_password_length); + +static ssize_t role_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) +{ + if (!strcmp(kobj->name, SETUP_PASSWD)) + return sysfs_emit(buf, "%s\n", BIOS_ADMIN); + + if (!strcmp(kobj->name, POWER_ON_PASSWD)) + return sysfs_emit(buf, "%s\n", POWER_ON); + + return -EIO; +} + +static struct kobj_attribute password_role = __ATTR_RO(role); + +static ssize_t mechanism_show(struct kobject *kobj, struct kobj_attribute *attr, + char *buf) +{ + int i = get_password_instance_id(kobj); + + if (i < 0) + return i; + + if (bioscfg_drv.password_data[i].mechanism != PASSWORD) + return -EINVAL; + + return sysfs_emit(buf, "%s\n", PASSWD_MECHANISM_TYPES); +} + +static struct kobj_attribute password_mechanism = __ATTR_RO(mechanism); + +ATTRIBUTE_VALUES_PROPERTY_SHOW(encodings, password, SEMICOLON_SEP); +static struct kobj_attribute password_encodings_val = __ATTR_RO(encodings); + +static struct attribute *password_attrs[] = { + &password_is_password_set.attr, + &password_min_password_length.attr, + &password_max_password_length.attr, + &password_current_password.attr, + &password_new_password.attr, + &password_role.attr, + &password_mechanism.attr, + &password_encodings_val.attr, + NULL +}; + +static const struct attribute_group password_attr_group = { + .attrs = password_attrs +}; + +int hp_alloc_password_data(void) +{ + bioscfg_drv.password_instances_count = hp_get_instance_count(HP_WMI_BIOS_PASSWORD_GUID); + bioscfg_drv.password_data = kcalloc(bioscfg_drv.password_instances_count, + sizeof(*bioscfg_drv.password_data), GFP_KERNEL); + if (!bioscfg_drv.password_data) { + bioscfg_drv.password_instances_count = 0; + return -ENOMEM; + } + + return 0; +} + +/* Expected Values types associated with each element */ +static const acpi_object_type expected_password_types[] = { + [NAME] = ACPI_TYPE_STRING, + [VALUE] = ACPI_TYPE_STRING, + [PATH] = ACPI_TYPE_STRING, + [IS_READONLY] = ACPI_TYPE_INTEGER, + [DISPLAY_IN_UI] = ACPI_TYPE_INTEGER, + [REQUIRES_PHYSICAL_PRESENCE] = ACPI_TYPE_INTEGER, + [SEQUENCE] = ACPI_TYPE_INTEGER, + [PREREQUISITES_SIZE] = ACPI_TYPE_INTEGER, + [PREREQUISITES] = ACPI_TYPE_STRING, + [SECURITY_LEVEL] = ACPI_TYPE_INTEGER, + [PSWD_MIN_LENGTH] = ACPI_TYPE_INTEGER, + [PSWD_MAX_LENGTH] = ACPI_TYPE_INTEGER, + [PSWD_SIZE] = ACPI_TYPE_INTEGER, + [PSWD_ENCODINGS] = ACPI_TYPE_STRING, + [PSWD_IS_SET] = ACPI_TYPE_INTEGER, +}; + +static int hp_populate_password_elements_from_package(union acpi_object *password_obj, + int password_obj_count, + int instance_id) +{ + char *str_value = NULL; + int value_len; + int ret; + u32 size; + u32 int_value = 0; + int elem; + int reqs; + int eloc; + int pos_values; + struct password_data *password_data = &bioscfg_drv.password_data[instance_id]; + + if (!password_obj) + return -EINVAL; + + for (elem = 1, eloc = 1; elem < password_obj_count; elem++, eloc++) { + /* ONLY look at the first PASSWORD_ELEM_CNT elements */ + if (eloc == PSWD_ELEM_CNT) + goto exit_package; + + switch (password_obj[elem].type) { + case ACPI_TYPE_STRING: + if (PREREQUISITES != elem && PSWD_ENCODINGS != elem) { + ret = hp_convert_hexstr_to_str(password_obj[elem].string.pointer, + password_obj[elem].string.length, + &str_value, &value_len); + if (ret) + continue; + } + break; + case ACPI_TYPE_INTEGER: + int_value = (u32)password_obj[elem].integer.value; + break; + default: + pr_warn("Unsupported object type [%d]\n", password_obj[elem].type); + continue; + } + + /* Check that both expected and read object type match */ + if (expected_password_types[eloc] != password_obj[elem].type) { + pr_err("Error expected type %d for elem %d, but got type %d instead\n", + expected_password_types[eloc], elem, password_obj[elem].type); + kfree(str_value); + return -EIO; + } + + /* Assign appropriate element value to corresponding field*/ + switch (eloc) { + case VALUE: + break; + case PATH: + strscpy(password_data->common.path, str_value, + sizeof(password_data->common.path)); + break; + case IS_READONLY: + password_data->common.is_readonly = int_value; + break; + case DISPLAY_IN_UI: + password_data->common.display_in_ui = int_value; + break; + case REQUIRES_PHYSICAL_PRESENCE: + password_data->common.requires_physical_presence = int_value; + break; + case SEQUENCE: + password_data->common.sequence = int_value; + break; + case PREREQUISITES_SIZE: + if (int_value > MAX_PREREQUISITES_SIZE) { + pr_warn("Prerequisites size value exceeded the maximum number of elements supported or data may be malformed\n"); + int_value = MAX_PREREQUISITES_SIZE; + } + password_data->common.prerequisites_size = int_value; + + /* This step is needed to keep the expected + * element list pointing to the right obj[elem].type + * when the size is zero. PREREQUISITES + * object is omitted by BIOS when the size is + * zero. + */ + if (int_value == 0) + eloc++; + break; + case PREREQUISITES: + size = min_t(u32, password_data->common.prerequisites_size, + MAX_PREREQUISITES_SIZE); + + for (reqs = 0; reqs < size; reqs++) { + ret = hp_convert_hexstr_to_str(password_obj[elem + reqs].string.pointer, + password_obj[elem + reqs].string.length, + &str_value, &value_len); + + if (ret) + break; + + strscpy(password_data->common.prerequisites[reqs], + str_value, + sizeof(password_data->common.prerequisites[reqs])); + + kfree(str_value); + str_value = NULL; + + } + break; + case SECURITY_LEVEL: + password_data->common.security_level = int_value; + break; + case PSWD_MIN_LENGTH: + password_data->min_password_length = int_value; + break; + case PSWD_MAX_LENGTH: + password_data->max_password_length = int_value; + break; + case PSWD_SIZE: + + if (int_value > MAX_ENCODINGS_SIZE) { + pr_warn("Password Encoding size value exceeded the maximum number of elements supported or data may be malformed\n"); + int_value = MAX_ENCODINGS_SIZE; + } + password_data->encodings_size = int_value; + + /* This step is needed to keep the expected + * element list pointing to the right obj[elem].type + * when the size is zero. PSWD_ENCODINGS + * object is omitted by BIOS when the size is + * zero. + */ + if (int_value == 0) + eloc++; + break; + case PSWD_ENCODINGS: + size = min_t(u32, password_data->encodings_size, MAX_ENCODINGS_SIZE); + for (pos_values = 0; pos_values < size; pos_values++) { + ret = hp_convert_hexstr_to_str(password_obj[elem + pos_values].string.pointer, + password_obj[elem + pos_values].string.length, + &str_value, &value_len); + if (ret) + break; + + strscpy(password_data->encodings[pos_values], + str_value, + sizeof(password_data->encodings[pos_values])); + kfree(str_value); + str_value = NULL; + + } + break; + case PSWD_IS_SET: + password_data->is_enabled = int_value; + break; + default: + pr_warn("Invalid element: %d found in Password attribute or data may be malformed\n", elem); + break; + } + + kfree(str_value); + str_value = NULL; + } + +exit_package: + kfree(str_value); + return 0; +} + +/** + * hp_populate_password_package_data() + * Populate all properties for an instance under password attribute + * + * @password_obj: ACPI object with password data + * @instance_id: The instance to enumerate + * @attr_name_kobj: The parent kernel object + */ +int hp_populate_password_package_data(union acpi_object *password_obj, int instance_id, + struct kobject *attr_name_kobj) +{ + struct password_data *password_data = &bioscfg_drv.password_data[instance_id]; + + password_data->attr_name_kobj = attr_name_kobj; + + hp_populate_password_elements_from_package(password_obj, + password_obj->package.count, + instance_id); + + hp_friendly_user_name_update(password_data->common.path, + attr_name_kobj->name, + password_data->common.display_name, + sizeof(password_data->common.display_name)); + + if (!strcmp(attr_name_kobj->name, SETUP_PASSWD)) + return sysfs_create_group(attr_name_kobj, &password_attr_group); + + return sysfs_create_group(attr_name_kobj, &password_attr_group); +} + +static int hp_populate_password_elements_from_buffer(u8 *buffer_ptr, u32 *buffer_size, + int instance_id) +{ + int values; + int isreadonly; + struct password_data *password_data = &bioscfg_drv.password_data[instance_id]; + int ret = 0; + + /* + * Only data relevant to this driver and its functionality is + * read. BIOS defines the order in which each * element is + * read. Element 0 data is not relevant to this + * driver hence it is ignored. For clarity, all element names + * (DISPLAY_IN_UI) which defines the order in which is read + * and the name matches the variable where the data is stored. + * + * In earlier implementation, reported errors were ignored + * causing the data to remain uninitialized. It is not + * possible to determine if data read from BIOS is valid or + * not. It is for this reason functions may return a error + * without validating the data itself. + */ + + // VALUE: + ret = hp_get_string_from_buffer(&buffer_ptr, buffer_size, password_data->current_password, + sizeof(password_data->current_password)); + if (ret < 0) + goto buffer_exit; + + // COMMON: + ret = hp_get_common_data_from_buffer(&buffer_ptr, buffer_size, + &password_data->common); + if (ret < 0) + goto buffer_exit; + + // PSWD_MIN_LENGTH: + ret = hp_get_integer_from_buffer(&buffer_ptr, buffer_size, + &password_data->min_password_length); + if (ret < 0) + goto buffer_exit; + + // PSWD_MAX_LENGTH: + ret = hp_get_integer_from_buffer(&buffer_ptr, buffer_size, + &password_data->max_password_length); + if (ret < 0) + goto buffer_exit; + + // PSWD_SIZE: + ret = hp_get_integer_from_buffer(&buffer_ptr, buffer_size, + &password_data->encodings_size); + if (ret < 0) + goto buffer_exit; + + if (password_data->encodings_size > MAX_ENCODINGS_SIZE) { + /* Report a message and limit possible values size to maximum value */ + pr_warn("Password Encoding size value exceeded the maximum number of elements supported or data may be malformed\n"); + password_data->encodings_size = MAX_ENCODINGS_SIZE; + } + + // PSWD_ENCODINGS: + for (values = 0; values < password_data->encodings_size; values++) { + ret = hp_get_string_from_buffer(&buffer_ptr, buffer_size, + password_data->encodings[values], + sizeof(password_data->encodings[values])); + if (ret < 0) + break; + } + + // PSWD_IS_SET: + ret = hp_get_integer_from_buffer(&buffer_ptr, buffer_size, &isreadonly); + if (ret < 0) + goto buffer_exit; + + password_data->is_enabled = isreadonly ? true : false; + +buffer_exit: + return ret; +} + +/** + * hp_populate_password_buffer_data() + * Populate all properties for an instance under password object attribute + * + * @buffer_ptr: Buffer pointer + * @buffer_size: Buffer size + * @instance_id: The instance to enumerate + * @attr_name_kobj: The parent kernel object + */ +int hp_populate_password_buffer_data(u8 *buffer_ptr, u32 *buffer_size, int instance_id, + struct kobject *attr_name_kobj) +{ + struct password_data *password_data = &bioscfg_drv.password_data[instance_id]; + int ret = 0; + + password_data->attr_name_kobj = attr_name_kobj; + + /* Populate Password attributes */ + ret = hp_populate_password_elements_from_buffer(buffer_ptr, buffer_size, + instance_id); + if (ret < 0) + return ret; + + hp_friendly_user_name_update(password_data->common.path, + attr_name_kobj->name, + password_data->common.display_name, + sizeof(password_data->common.display_name)); + if (!strcmp(attr_name_kobj->name, SETUP_PASSWD)) + return sysfs_create_group(attr_name_kobj, &password_attr_group); + + return sysfs_create_group(attr_name_kobj, &password_attr_group); +} + +/** + * hp_exit_password_attributes() - Clear all attribute data + * + * Clears all data allocated for this group of attributes + */ +void hp_exit_password_attributes(void) +{ + int instance_id; + + for (instance_id = 0; instance_id < bioscfg_drv.password_instances_count; + instance_id++) { + struct kobject *attr_name_kobj = + bioscfg_drv.password_data[instance_id].attr_name_kobj; + + if (attr_name_kobj) { + if (!strcmp(attr_name_kobj->name, SETUP_PASSWD)) + sysfs_remove_group(attr_name_kobj, + &password_attr_group); + else + sysfs_remove_group(attr_name_kobj, + &password_attr_group); + } + } + bioscfg_drv.password_instances_count = 0; + kfree(bioscfg_drv.password_data); + bioscfg_drv.password_data = NULL; +} |