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1// SPDX-License-Identifier: GPL-2.02/*3 * Functions corresponding to password object type attributes under4 * BIOS PASSWORD for use with hp-bioscfg driver.5 *6 * Copyright (c) 2022 HP Development Company, L.P.7 */8 9#include "bioscfg.h"10 11GET_INSTANCE_ID(password);12/*13 * Clear all passwords copied to memory for a particular14 * authentication instance15 */16static int clear_passwords(const int instance)17{18 struct password_data *password_data = &bioscfg_drv.password_data[instance];19 20 if (!password_data->is_enabled)21 return 0;22 23 memset(password_data->current_password,24 0, sizeof(password_data->current_password));25 memset(password_data->new_password,26 0, sizeof(password_data->new_password));27 28 return 0;29}30 31/*32 * Clear all credentials copied to memory for both Power-ON and Setup33 * BIOS instances34 */35int hp_clear_all_credentials(void)36{37 int count = bioscfg_drv.password_instances_count;38 int instance;39 40 /* clear all passwords */41 for (instance = 0; instance < count; instance++)42 clear_passwords(instance);43 44 /* clear auth_token */45 kfree(bioscfg_drv.spm_data.auth_token);46 bioscfg_drv.spm_data.auth_token = NULL;47 48 return 0;49}50 51int hp_get_password_instance_for_type(const char *name)52{53 int count = bioscfg_drv.password_instances_count;54 int instance;55 56 for (instance = 0; instance < count; instance++)57 if (!strcmp(bioscfg_drv.password_data[instance].common.display_name, name))58 return instance;59 60 return -EINVAL;61}62 63static int validate_password_input(int instance_id, const char *buf)64{65 int length;66 struct password_data *password_data = &bioscfg_drv.password_data[instance_id];67 68 length = strlen(buf);69 if (buf[length - 1] == '\n')70 length--;71 72 if (length > MAX_PASSWD_SIZE)73 return INVALID_BIOS_AUTH;74 75 if (password_data->min_password_length > length ||76 password_data->max_password_length < length)77 return INVALID_BIOS_AUTH;78 return SUCCESS;79}80 81ATTRIBUTE_N_PROPERTY_SHOW(is_enabled, password);82static struct kobj_attribute password_is_password_set = __ATTR_RO(is_enabled);83 84static int store_password_instance(struct kobject *kobj, const char *buf,85 size_t count, bool is_current)86{87 char *buf_cp;88 int id, ret = 0;89 90 buf_cp = kstrdup(buf, GFP_KERNEL);91 if (!buf_cp)92 return -ENOMEM;93 94 ret = hp_enforce_single_line_input(buf_cp, count);95 if (!ret) {96 id = get_password_instance_id(kobj);97 98 if (id >= 0)99 ret = validate_password_input(id, buf_cp);100 }101 102 if (!ret) {103 if (is_current)104 strscpy(bioscfg_drv.password_data[id].current_password, buf_cp);105 else106 strscpy(bioscfg_drv.password_data[id].new_password, buf_cp);107 }108 109 kfree(buf_cp);110 return ret < 0 ? ret : count;111}112 113static ssize_t current_password_store(struct kobject *kobj,114 struct kobj_attribute *attr,115 const char *buf, size_t count)116{117 return store_password_instance(kobj, buf, count, true);118}119 120static struct kobj_attribute password_current_password = __ATTR_WO(current_password);121 122static ssize_t new_password_store(struct kobject *kobj,123 struct kobj_attribute *attr,124 const char *buf, size_t count)125{126 return store_password_instance(kobj, buf, count, true);127}128 129static struct kobj_attribute password_new_password = __ATTR_WO(new_password);130 131ATTRIBUTE_N_PROPERTY_SHOW(min_password_length, password);132static struct kobj_attribute password_min_password_length = __ATTR_RO(min_password_length);133 134ATTRIBUTE_N_PROPERTY_SHOW(max_password_length, password);135static struct kobj_attribute password_max_password_length = __ATTR_RO(max_password_length);136 137static ssize_t role_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf)138{139 if (!strcmp(kobj->name, SETUP_PASSWD))140 return sysfs_emit(buf, "%s\n", BIOS_ADMIN);141 142 if (!strcmp(kobj->name, POWER_ON_PASSWD))143 return sysfs_emit(buf, "%s\n", POWER_ON);144 145 return -EIO;146}147 148static struct kobj_attribute password_role = __ATTR_RO(role);149 150static ssize_t mechanism_show(struct kobject *kobj, struct kobj_attribute *attr,151 char *buf)152{153 int i = get_password_instance_id(kobj);154 155 if (i < 0)156 return i;157 158 if (bioscfg_drv.password_data[i].mechanism != PASSWORD)159 return -EINVAL;160 161 return sysfs_emit(buf, "%s\n", PASSWD_MECHANISM_TYPES);162}163 164static struct kobj_attribute password_mechanism = __ATTR_RO(mechanism);165 166ATTRIBUTE_VALUES_PROPERTY_SHOW(encodings, password, SEMICOLON_SEP);167static struct kobj_attribute password_encodings_val = __ATTR_RO(encodings);168 169static struct attribute *password_attrs[] = {170 &password_is_password_set.attr,171 &password_min_password_length.attr,172 &password_max_password_length.attr,173 &password_current_password.attr,174 &password_new_password.attr,175 &password_role.attr,176 &password_mechanism.attr,177 &password_encodings_val.attr,178 NULL179};180 181static const struct attribute_group password_attr_group = {182 .attrs = password_attrs183};184 185int hp_alloc_password_data(void)186{187 bioscfg_drv.password_instances_count = hp_get_instance_count(HP_WMI_BIOS_PASSWORD_GUID);188 bioscfg_drv.password_data = kcalloc(bioscfg_drv.password_instances_count,189 sizeof(*bioscfg_drv.password_data), GFP_KERNEL);190 if (!bioscfg_drv.password_data) {191 bioscfg_drv.password_instances_count = 0;192 return -ENOMEM;193 }194 195 return 0;196}197 198/* Expected Values types associated with each element */199static const acpi_object_type expected_password_types[] = {200 [NAME] = ACPI_TYPE_STRING,201 [VALUE] = ACPI_TYPE_STRING,202 [PATH] = ACPI_TYPE_STRING,203 [IS_READONLY] = ACPI_TYPE_INTEGER,204 [DISPLAY_IN_UI] = ACPI_TYPE_INTEGER,205 [REQUIRES_PHYSICAL_PRESENCE] = ACPI_TYPE_INTEGER,206 [SEQUENCE] = ACPI_TYPE_INTEGER,207 [PREREQUISITES_SIZE] = ACPI_TYPE_INTEGER,208 [PREREQUISITES] = ACPI_TYPE_STRING,209 [SECURITY_LEVEL] = ACPI_TYPE_INTEGER,210 [PSWD_MIN_LENGTH] = ACPI_TYPE_INTEGER,211 [PSWD_MAX_LENGTH] = ACPI_TYPE_INTEGER,212 [PSWD_SIZE] = ACPI_TYPE_INTEGER,213 [PSWD_ENCODINGS] = ACPI_TYPE_STRING,214 [PSWD_IS_SET] = ACPI_TYPE_INTEGER,215};216 217static int hp_populate_password_elements_from_package(union acpi_object *password_obj,218 int password_obj_count,219 int instance_id)220{221 char *str_value = NULL;222 int value_len;223 int ret;224 u32 size;225 u32 int_value = 0;226 int elem;227 int reqs;228 int eloc;229 int pos_values;230 struct password_data *password_data = &bioscfg_drv.password_data[instance_id];231 232 if (!password_obj)233 return -EINVAL;234 235 for (elem = 1, eloc = 1; elem < password_obj_count; elem++, eloc++) {236 /* ONLY look at the first PASSWORD_ELEM_CNT elements */237 if (eloc == PSWD_ELEM_CNT)238 goto exit_package;239 240 switch (password_obj[elem].type) {241 case ACPI_TYPE_STRING:242 if (PREREQUISITES != elem && PSWD_ENCODINGS != elem) {243 ret = hp_convert_hexstr_to_str(password_obj[elem].string.pointer,244 password_obj[elem].string.length,245 &str_value, &value_len);246 if (ret)247 continue;248 }249 break;250 case ACPI_TYPE_INTEGER:251 int_value = (u32)password_obj[elem].integer.value;252 break;253 default:254 pr_warn("Unsupported object type [%d]\n", password_obj[elem].type);255 continue;256 }257 258 /* Check that both expected and read object type match */259 if (expected_password_types[eloc] != password_obj[elem].type) {260 pr_err("Error expected type %d for elem %d, but got type %d instead\n",261 expected_password_types[eloc], elem, password_obj[elem].type);262 kfree(str_value);263 return -EIO;264 }265 266 /* Assign appropriate element value to corresponding field*/267 switch (eloc) {268 case VALUE:269 break;270 case PATH:271 strscpy(password_data->common.path, str_value);272 break;273 case IS_READONLY:274 password_data->common.is_readonly = int_value;275 break;276 case DISPLAY_IN_UI:277 password_data->common.display_in_ui = int_value;278 break;279 case REQUIRES_PHYSICAL_PRESENCE:280 password_data->common.requires_physical_presence = int_value;281 break;282 case SEQUENCE:283 password_data->common.sequence = int_value;284 break;285 case PREREQUISITES_SIZE:286 if (int_value > MAX_PREREQUISITES_SIZE) {287 pr_warn("Prerequisites size value exceeded the maximum number of elements supported or data may be malformed\n");288 int_value = MAX_PREREQUISITES_SIZE;289 }290 password_data->common.prerequisites_size = int_value;291 292 /* This step is needed to keep the expected293 * element list pointing to the right obj[elem].type294 * when the size is zero. PREREQUISITES295 * object is omitted by BIOS when the size is296 * zero.297 */298 if (int_value == 0)299 eloc++;300 break;301 case PREREQUISITES:302 size = min_t(u32, password_data->common.prerequisites_size,303 MAX_PREREQUISITES_SIZE);304 305 for (reqs = 0; reqs < size; reqs++) {306 ret = hp_convert_hexstr_to_str(password_obj[elem + reqs].string.pointer,307 password_obj[elem + reqs].string.length,308 &str_value, &value_len);309 310 if (ret)311 break;312 313 strscpy(password_data->common.prerequisites[reqs], str_value);314 315 kfree(str_value);316 str_value = NULL;317 318 }319 break;320 case SECURITY_LEVEL:321 password_data->common.security_level = int_value;322 break;323 case PSWD_MIN_LENGTH:324 password_data->min_password_length = int_value;325 break;326 case PSWD_MAX_LENGTH:327 password_data->max_password_length = int_value;328 break;329 case PSWD_SIZE:330 331 if (int_value > MAX_ENCODINGS_SIZE) {332 pr_warn("Password Encoding size value exceeded the maximum number of elements supported or data may be malformed\n");333 int_value = MAX_ENCODINGS_SIZE;334 }335 password_data->encodings_size = int_value;336 337 /* This step is needed to keep the expected338 * element list pointing to the right obj[elem].type339 * when the size is zero. PSWD_ENCODINGS340 * object is omitted by BIOS when the size is341 * zero.342 */343 if (int_value == 0)344 eloc++;345 break;346 case PSWD_ENCODINGS:347 size = min_t(u32, password_data->encodings_size, MAX_ENCODINGS_SIZE);348 for (pos_values = 0; pos_values < size; pos_values++) {349 ret = hp_convert_hexstr_to_str(password_obj[elem + pos_values].string.pointer,350 password_obj[elem + pos_values].string.length,351 &str_value, &value_len);352 if (ret)353 break;354 355 strscpy(password_data->encodings[pos_values], str_value);356 kfree(str_value);357 str_value = NULL;358 359 }360 break;361 case PSWD_IS_SET:362 password_data->is_enabled = int_value;363 break;364 default:365 pr_warn("Invalid element: %d found in Password attribute or data may be malformed\n", elem);366 break;367 }368 369 kfree(str_value);370 str_value = NULL;371 }372 373exit_package:374 kfree(str_value);375 return 0;376}377 378/**379 * hp_populate_password_package_data()380 * Populate all properties for an instance under password attribute381 *382 * @password_obj: ACPI object with password data383 * @instance_id: The instance to enumerate384 * @attr_name_kobj: The parent kernel object385 */386int hp_populate_password_package_data(union acpi_object *password_obj, int instance_id,387 struct kobject *attr_name_kobj)388{389 struct password_data *password_data = &bioscfg_drv.password_data[instance_id];390 391 password_data->attr_name_kobj = attr_name_kobj;392 393 hp_populate_password_elements_from_package(password_obj,394 password_obj->package.count,395 instance_id);396 397 hp_friendly_user_name_update(password_data->common.path,398 attr_name_kobj->name,399 password_data->common.display_name,400 sizeof(password_data->common.display_name));401 402 if (!strcmp(attr_name_kobj->name, SETUP_PASSWD))403 return sysfs_create_group(attr_name_kobj, &password_attr_group);404 405 return sysfs_create_group(attr_name_kobj, &password_attr_group);406}407 408static int hp_populate_password_elements_from_buffer(u8 *buffer_ptr, u32 *buffer_size,409 int instance_id)410{411 int values;412 int isreadonly;413 struct password_data *password_data = &bioscfg_drv.password_data[instance_id];414 int ret = 0;415 416 /*417 * Only data relevant to this driver and its functionality is418 * read. BIOS defines the order in which each * element is419 * read. Element 0 data is not relevant to this420 * driver hence it is ignored. For clarity, all element names421 * (DISPLAY_IN_UI) which defines the order in which is read422 * and the name matches the variable where the data is stored.423 *424 * In earlier implementation, reported errors were ignored425 * causing the data to remain uninitialized. It is not426 * possible to determine if data read from BIOS is valid or427 * not. It is for this reason functions may return a error428 * without validating the data itself.429 */430 431 // VALUE:432 ret = hp_get_string_from_buffer(&buffer_ptr, buffer_size, password_data->current_password,433 sizeof(password_data->current_password));434 if (ret < 0)435 goto buffer_exit;436 437 // COMMON:438 ret = hp_get_common_data_from_buffer(&buffer_ptr, buffer_size,439 &password_data->common);440 if (ret < 0)441 goto buffer_exit;442 443 // PSWD_MIN_LENGTH:444 ret = hp_get_integer_from_buffer(&buffer_ptr, buffer_size,445 &password_data->min_password_length);446 if (ret < 0)447 goto buffer_exit;448 449 // PSWD_MAX_LENGTH:450 ret = hp_get_integer_from_buffer(&buffer_ptr, buffer_size,451 &password_data->max_password_length);452 if (ret < 0)453 goto buffer_exit;454 455 // PSWD_SIZE:456 ret = hp_get_integer_from_buffer(&buffer_ptr, buffer_size,457 &password_data->encodings_size);458 if (ret < 0)459 goto buffer_exit;460 461 if (password_data->encodings_size > MAX_ENCODINGS_SIZE) {462 /* Report a message and limit possible values size to maximum value */463 pr_warn("Password Encoding size value exceeded the maximum number of elements supported or data may be malformed\n");464 password_data->encodings_size = MAX_ENCODINGS_SIZE;465 }466 467 // PSWD_ENCODINGS:468 for (values = 0; values < password_data->encodings_size; values++) {469 ret = hp_get_string_from_buffer(&buffer_ptr, buffer_size,470 password_data->encodings[values],471 sizeof(password_data->encodings[values]));472 if (ret < 0)473 break;474 }475 476 // PSWD_IS_SET:477 ret = hp_get_integer_from_buffer(&buffer_ptr, buffer_size, &isreadonly);478 if (ret < 0)479 goto buffer_exit;480 481 password_data->is_enabled = isreadonly ? true : false;482 483buffer_exit:484 return ret;485}486 487/**488 * hp_populate_password_buffer_data()489 * Populate all properties for an instance under password object attribute490 *491 * @buffer_ptr: Buffer pointer492 * @buffer_size: Buffer size493 * @instance_id: The instance to enumerate494 * @attr_name_kobj: The parent kernel object495 */496int hp_populate_password_buffer_data(u8 *buffer_ptr, u32 *buffer_size, int instance_id,497 struct kobject *attr_name_kobj)498{499 struct password_data *password_data = &bioscfg_drv.password_data[instance_id];500 int ret = 0;501 502 password_data->attr_name_kobj = attr_name_kobj;503 504 /* Populate Password attributes */505 ret = hp_populate_password_elements_from_buffer(buffer_ptr, buffer_size,506 instance_id);507 if (ret < 0)508 return ret;509 510 hp_friendly_user_name_update(password_data->common.path,511 attr_name_kobj->name,512 password_data->common.display_name,513 sizeof(password_data->common.display_name));514 if (!strcmp(attr_name_kobj->name, SETUP_PASSWD))515 return sysfs_create_group(attr_name_kobj, &password_attr_group);516 517 return sysfs_create_group(attr_name_kobj, &password_attr_group);518}519 520/**521 * hp_exit_password_attributes() - Clear all attribute data522 *523 * Clears all data allocated for this group of attributes524 */525void hp_exit_password_attributes(void)526{527 int instance_id;528 529 for (instance_id = 0; instance_id < bioscfg_drv.password_instances_count;530 instance_id++) {531 struct kobject *attr_name_kobj =532 bioscfg_drv.password_data[instance_id].attr_name_kobj;533 534 if (attr_name_kobj) {535 if (!strcmp(attr_name_kobj->name, SETUP_PASSWD))536 sysfs_remove_group(attr_name_kobj,537 &password_attr_group);538 else539 sysfs_remove_group(attr_name_kobj,540 &password_attr_group);541 }542 }543 bioscfg_drv.password_instances_count = 0;544 kfree(bioscfg_drv.password_data);545 bioscfg_drv.password_data = NULL;546}547