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1// SPDX-License-Identifier: GPL-2.02/*3 * Functions corresponding to password object type attributes under BIOS Password Object GUID for4 * use with dell-wmi-sysman5 *6 * Copyright (c) 2020 Dell Inc.7 */8 9#include "dell-wmi-sysman.h"10 11enum po_properties {IS_PASS_SET = 1, MIN_PASS_LEN, MAX_PASS_LEN};12 13get_instance_id(po);14 15static ssize_t is_enabled_show(struct kobject *kobj, struct kobj_attribute *attr,16 char *buf)17{18 int instance_id = get_po_instance_id(kobj);19 union acpi_object *obj;20 ssize_t ret;21 22 if (instance_id < 0)23 return instance_id;24 25 /* need to use specific instance_id and guid combination to get right data */26 obj = get_wmiobj_pointer(instance_id, DELL_WMI_BIOS_PASSOBJ_ATTRIBUTE_GUID);27 if (!obj)28 return -EIO;29 if (obj->package.elements[IS_PASS_SET].type != ACPI_TYPE_INTEGER) {30 kfree(obj);31 return -EINVAL;32 }33 ret = snprintf(buf, PAGE_SIZE, "%lld\n", obj->package.elements[IS_PASS_SET].integer.value);34 kfree(obj);35 return ret;36}37 38static struct kobj_attribute po_is_pass_set = __ATTR_RO(is_enabled);39 40static ssize_t current_password_store(struct kobject *kobj,41 struct kobj_attribute *attr,42 const char *buf, size_t count)43{44 char *target = NULL;45 int length;46 47 length = strlen(buf);48 if (buf[length-1] == '\n')49 length--;50 51 /* firmware does verifiation of min/max password length,52 * hence only check for not exceeding MAX_BUFF here.53 */54 if (length >= MAX_BUFF)55 return -EINVAL;56 57 if (strcmp(kobj->name, "Admin") == 0)58 target = wmi_priv.current_admin_password;59 else if (strcmp(kobj->name, "System") == 0)60 target = wmi_priv.current_system_password;61 if (!target)62 return -EIO;63 memcpy(target, buf, length);64 target[length] = '\0';65 66 return count;67}68 69static struct kobj_attribute po_current_password = __ATTR_WO(current_password);70 71static ssize_t new_password_store(struct kobject *kobj,72 struct kobj_attribute *attr,73 const char *buf, size_t count)74{75 char *p, *buf_cp;76 int ret;77 78 buf_cp = kstrdup(buf, GFP_KERNEL);79 if (!buf_cp)80 return -ENOMEM;81 p = memchr(buf_cp, '\n', count);82 83 if (p != NULL)84 *p = '\0';85 if (strlen(buf_cp) > MAX_BUFF) {86 ret = -EINVAL;87 goto out;88 }89 90 ret = set_new_password(kobj->name, buf_cp);91 92out:93 kfree(buf_cp);94 return ret ? ret : count;95}96 97static struct kobj_attribute po_new_password = __ATTR_WO(new_password);98 99attribute_n_property_show(min_password_length, po);100static struct kobj_attribute po_min_pass_length = __ATTR_RO(min_password_length);101 102attribute_n_property_show(max_password_length, po);103static struct kobj_attribute po_max_pass_length = __ATTR_RO(max_password_length);104 105static ssize_t mechanism_show(struct kobject *kobj, struct kobj_attribute *attr,106 char *buf)107{108 return sprintf(buf, "password\n");109}110 111static struct kobj_attribute po_mechanism = __ATTR_RO(mechanism);112 113static ssize_t role_show(struct kobject *kobj, struct kobj_attribute *attr,114 char *buf)115{116 if (strcmp(kobj->name, "Admin") == 0)117 return sprintf(buf, "bios-admin\n");118 else if (strcmp(kobj->name, "System") == 0)119 return sprintf(buf, "power-on\n");120 return -EIO;121}122 123static struct kobj_attribute po_role = __ATTR_RO(role);124 125static struct attribute *po_attrs[] = {126 &po_is_pass_set.attr,127 &po_min_pass_length.attr,128 &po_max_pass_length.attr,129 &po_current_password.attr,130 &po_new_password.attr,131 &po_role.attr,132 &po_mechanism.attr,133 NULL,134};135 136static const struct attribute_group po_attr_group = {137 .attrs = po_attrs,138};139 140int alloc_po_data(void)141{142 int ret = 0;143 144 wmi_priv.po_instances_count = get_instance_count(DELL_WMI_BIOS_PASSOBJ_ATTRIBUTE_GUID);145 wmi_priv.po_data = kcalloc(wmi_priv.po_instances_count, sizeof(struct po_data), GFP_KERNEL);146 if (!wmi_priv.po_data) {147 wmi_priv.po_instances_count = 0;148 ret = -ENOMEM;149 }150 return ret;151}152 153/**154 * populate_po_data() - Populate all properties of an instance under password object attribute155 * @po_obj: ACPI object with password object data156 * @instance_id: The instance to enumerate157 * @attr_name_kobj: The parent kernel object158 */159int populate_po_data(union acpi_object *po_obj, int instance_id, struct kobject *attr_name_kobj)160{161 wmi_priv.po_data[instance_id].attr_name_kobj = attr_name_kobj;162 if (check_property_type(po, ATTR_NAME, ACPI_TYPE_STRING))163 return -EINVAL;164 strlcpy_attr(wmi_priv.po_data[instance_id].attribute_name,165 po_obj[ATTR_NAME].string.pointer);166 if (check_property_type(po, MIN_PASS_LEN, ACPI_TYPE_INTEGER))167 return -EINVAL;168 wmi_priv.po_data[instance_id].min_password_length =169 (uintptr_t)po_obj[MIN_PASS_LEN].string.pointer;170 if (check_property_type(po, MAX_PASS_LEN, ACPI_TYPE_INTEGER))171 return -EINVAL;172 wmi_priv.po_data[instance_id].max_password_length =173 (uintptr_t) po_obj[MAX_PASS_LEN].string.pointer;174 175 return sysfs_create_group(attr_name_kobj, &po_attr_group);176}177 178/**179 * exit_po_attributes() - Clear all attribute data180 *181 * Clears all data allocated for this group of attributes182 */183void exit_po_attributes(void)184{185 int instance_id;186 187 for (instance_id = 0; instance_id < wmi_priv.po_instances_count; instance_id++) {188 if (wmi_priv.po_data[instance_id].attr_name_kobj)189 sysfs_remove_group(wmi_priv.po_data[instance_id].attr_name_kobj,190 &po_attr_group);191 }192 wmi_priv.po_instances_count = 0;193 194 kfree(wmi_priv.po_data);195 wmi_priv.po_data = NULL;196}197